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Tim LEIGHTON / Peter BIRKIN
Ultrasonic Nozzle
http://www.sciencedaily.com
Revolutionary Ultrasonic Nozzle That Will Change the Way Water Cleans
Prof. Leighton (left) and Dr. Birkin with their ultrasonic nozzle device.
The revolutionary ultrasonic attachment for taps massively enhances the ability of water to clean.
A team of scientists from the University of Southampton have developed a revolutionary ultrasonic attachment for taps, which massively enhances the ability of water to clean.
Currently, industry uses excessive water, power and additives for cleaning. For example, it can take up to 100 tonnes of water to produce 1 tonne of clean wool after shearing. Many industrial processes also generate large quantities of contaminated run-off. The water from hosing down an abattoir represents a real health risk and cannot be allowed to enter the water supply. Purifying run-off is costly -- each cubic metre of water used for cleaning in the nuclear industry can cost around £10,000 to subsequently treat.
Professor Tim Leighton and Dr Peter Birkin's device works with cold water, minimal additives and consumes as much electrical power as a light bulb. Its application will be wide -- licenses have already been sold to a number of industries to look at cleaning in food preparation, hospitals, manufacturing and the home. The new technology consumes less water and power than the established competitor technologies.
Talking about the need for such a technology, Professor Leighton says: "Society runs on its ability to clean. Ineffective cleaning leads to food poisoning; failure of manufactured products such as precision watches and microchips; and poor construction -- from shipbuilding to space shuttles -- since dirty surfaces do not bond. The impact in healthcare is huge -- hospital-acquired infections, from instruments that aren't properly cleaned, cost the NHS £1 billion per year. There's a very obvious need for technologies that improve our ability to clean while saving on our most important resources, water and energy."
In recognition of their invention, Professor Leighton and Dr Birkin were awarded the Royal Society Brian Mercer Award for Innovation 2011 on Nov. 10.
Using the £250,000 award from the Royal Society, the team will develop products based on an ultrasonic nozzle which can fit on the end of a tap or hose. The device uses less water and power than the equivalent pressure washer (approximately 2 litres/minute compared to 20 litres/minute and less than 200 W compared to 2kW). It is also far less damaging as the stream pressure is less that 1/100th that of a pressure washer. Another advantage is that it generates far less runoff and aerosol (tiny atmospheric particles of water that can carry contaminates into the air to then settle and contaminate other surfaces). As it is able to use cold water, energy is saved on heating water.
Power washing generates large volumes of contaminated run-off and aerosols, presenting a hazard when used e.g. cleaning sewage systems or nuclear contamination. One of the main pieces of equipment currently used for industrial cleaning, ultrasonic cleaning baths, can only clean objects small enough to fit in them and the devices to be cleaned sit in a soup of contaminated liquid. Neither power washing (high-power pressure washing) nor ultrasonic cleaning baths can easily be scaled up and neither can be used on delicate materials such as hands or salad.
The new nozzle generates both bubbles and ultrasound. Both travel down the water stream to the dirty surface and there the bubbles act as microscopic 'smart scrubbers', seeking and entering crevices to remove dirt there using shear forces in the same way that currents in a babbling brook can strip off riverbank soil . The device can be used at a high-power and a low-power setting -- the latter being suitable for delicate products like hands and foodstuffs.
Licences to enable companies to bring the technology into their product lines have been negotiated with a number of companies to explore cleaning products for hospital hygiene, dentistry, food preparation, manufacturing and the power industries.
Dr Birkin says of the award: "The Brian Mercer award represents a significant milestone for the development of this technology and its possible exploitation. There is a clear gap in the funding system with ground breaking technology produced by universities, unexploited by industry. It is also difficult to find other suitable sources to take the technology further. It is in this situation that our invention found itself.
"In these trying times for innovative research, the foresight of the Royal Society to regularly sponsor and support these initiatives, should be congratulated. It is also pleasing that a significant 'blue skies' research effort within our team, over the last 10-15 year time period, has led to an understanding of the basic physical and chemical processes that underpin this technology. The Brian Mercer award, as well as being timely, will significantly enhance the chances of this novel technology making the leap from the lab and into wider society."
Professor Leighton adds: "Support for step changing innovation is vital if we are to have marketable technology to address the problems that will face society on the 10-50 year timescale, rather than just responding to today's problems."
The Brian Mercer Awards for Innovation were established by the Royal Society in 2001 following a bequest from the late Dr Brian Mercer, an enthusiastic inventor and entrepreneur. The awards aim to encourage these qualities in the next generation of scientists and provide a grant of £250,000 to develop an already proven concept or prototype into a near-market product.
CLEANING APPARATUS AND METHOD, AND MONITORING THEREOF
Inventor(s): LEIGHTON TIMOTHY GRANT [GB]; VIAN CHRISTOPHER JAMES BRADSHAW [GB]; BIRKIN PETER ROBERT [GB] + (LEIGHTON, TIMOTHY, GRANT, ; VIAN, CHRISTOPHER, JAMES, BRADSHAW, ; BIRKIN, PETER, ROBERT)
Applicant(s): UNIV SOUTHAMPTON [GB]; LEIGHTON TIMOTHY GRANT [GB]; VIAN CHRISTOPHER JAMES BRADSHAW [GB]; BIRKIN PETER ROBERT [GB] + (UNIVERSITY OF SOUTHAMPTON, ; LEIGHTON, TIMOTHY, GRANT, ; VIAN, CHRISTOPHER, JAMES, BRADSHAW, ; BIRKIN, PETER, ROBERT)
Classification: - international: B08B3/10 - European: B08B3/10; B08B3/12
Also published as: WO 2011023746 // GB 2472998 (A)
Abstract -- An apparatus for cleaning a surface, the apparatus comprising a body defining a chamber, an inlet for liquid flow into the chamber, an outlet for liquid flow from the chamber, a nozzle connected to the outlet for generating an output flow of liquid for cleaning a surface, an acoustic transducer associated with the body to introduce acoustic energy into the liquid within the chamber whereby the acoustic energy is present in the liquid flowing out of the nozzle, and a gas bubble generator for generating gas bubbles within the liquid flowing out of the nozzle.
The present invention relates to a cleaning apparatus and to a cleaning method, and to a method of monitoring cleaning.
Cleaning is an essential part of many research, commercial and public service processes, three obvious examples being manufacturing, healthcare, and laboratory work. Cleaning is often not simple: the object to be cleaned may be complicated, with many inaccessible crevices or chambers, and the potential contaminant very hazardous (a good example being the biopsy endoscope). The object to be cleaned may also be delicate (a good example of this being salad and vegetable matter, microchips, flesh, forensic material etc.) or tolerate minimal levels of scratching and damage (such as optical lenses, jewelry, prestige watch glasses and faces or prestige car finishes). Often the time available for cleaning is limited, as there is an imperative to move the object along to the next stage of processing or usage after it is cleaned (either because the number of units available for use is limited - as with the endoscope -, or because retardation of through-put cuts profile - as in the salad example).
Cleaning uses up huge amounts of water, even for 'natural' products: the production of 1 tonne of wool currently requires use of around 500 tonnes of water. When one considers the biohazardous waste of a hospital or abattoir, or the cleaning associated with chemical and nuclear plants, water conservation becomes a very major concern. The requirement for thorough cleaning is often in conflict with the requirements not to damage the target to be cleaned, not to use excessive water, not to contaminate the environment with chemical run-off, and not to use excessive energy or manpower or time.
Ultrasonic cleaning has been known in the art for many years, by the use of 'ultrasonic cleaning baths', whereby inertial cavitation and the generation of high speed liquid jets through bubble involution causes the removal of surface contaminants. The exploitation of cavitation in ultrasonic cleaning baths has for decades provided ultrasonic cleaning facilities that are suitable for those applications which have had robust objects to be cleaned (i.e. where cavitation erosion damage is not an issue), and where the size of the object to be cleaned is small enough to be immersed, and where the cleaning lacks the urgency which would necessitate a portable decontamination unit to supply on-the-spot cleaning resulting from, say, accidental contamination. In many instances of such cleaning, samples are either cleaned prior to further processing or dispersed within a suitable media as part of a larger methodology. Cleaning or processing is then facilitated by the employment of an ultrasonic bath. This invariably involves the immersion of a suitable container within the bath.
The cleaning action is often attributed to the generation of violent cavitation within the vessel itself and the interaction of these phenomena with the walls of the object in question. Cleaning action is attributed to cavitation events where the inertia of the liquid has had a dominant effect on the bubble dynamics, e.g. when a high-speed liquid jet passes through the bubble as a result of involution of the bubble wall and generates a blast wave on impact with liquid or solid; when bubbles collapse with almost spherical symmetry in 'transient' or 'inertiaP cavitation events, generating shock waves in the liquid and highly reactive chemical species such as free radicals; and when clouds of bubbles collapse in a concerted manner to magnify these effects to become greater than would be expected without the cloud effect. Hence the exact mechanism is often associated with 'transient cavitation' or more precisely inertial cavitation where the violent collapse phase results in the local generation of these extreme conditions.
However, such ultrasonic cleaning systems may suffer from one or more problems of surface damage, poor cleaning, particularly of three dimensional surfaces, e.g. crevices, and an inability to clean larger objects or surfaces. Furthermore the insertion of the object to be cleaned into an ultrasonic cleaning bath may disturb the sound field in a manner which degrades its ability to cause cleaning.
The present invention aims at least partially to overcome these problems of known surface cleaning processes, particularly ultrasonic cleaning.
The present invention provides an apparatus for cleaning a surface, the apparatus comprising a body defining a chamber, an inlet for liquid flow into the chamber, an outlet for liquid flow from the chamber, a nozzle connected to the outlet for generating an output flow of liquid for cleaning a surface, an acoustic transducer associated with the body to introduce acoustic energy into the liquid within the chamber whereby the acoustic energy is present in the liquid flowing out of the nozzle, and a gas bubble generator for generating gas bubbles within the liquid flowing out of the nozzle.
Preferably, the bubble generator comprises electrodes which are adapted to generate gas bubbles electrolytically within the liquid. Typically, the electrode comprises an array of electrically conductive wires extending across a direction of liquid flow.
Optionally, the gas bubble generator is located within the nozzle.
The apparatus may further comprise a first controller for the gas bubble generator which is adapted to control the gas bubble generator to generate pulses of gas bubbles.
The apparatus may further comprise a second controller for the acoustic transducer which is adapted to control the acoustic transducer to generate pulses of acoustic energy. Preferably, the second controller is adapted to switch the acoustic transducer on and off intermittently to produce pulses of acoustic energy. The apparatus may further comprise a modulator to provide an amplitude or frequency modulation of the pulses of acoustic energy.
Preferably, the first and second controllers are coordinated so that gas bubbles and pulses of acoustic energy are generated with a mutually controlled time relationship.
This coordination ensures that sound and bubbles can occur at the same time at a surface location to be cleaned. Their relative on/off timings at the nozzle can be varied to achieve this occurrence by taking into account the different travel times of sound and bubbles down the liquid, which may be a stream, and this depends on the length of liquid between the nozzle and the surface to be cleaned. The sound travels through the liquid at a velocity of over 1 km/second whereas the bubble velocity is related to the flow rate of the liquid. Once the sound is on, it can then also be amplitude or frequency modulated. Accordingly, in accordance with this particular preferred implemenation, it is possible to coordinate in timing of the two effects: the sound field is turned off entirely while the bubble swarm is generated and transferred to the surface. Once the swarm has reached the surface the sound field is activated. This sound field can be continuous or amplitude or frequency modulated.
The sound field is off whilst the bubbles travel down the stream in order to prevent colaescene of bubbles whilst they travel. This is the simplest implemenation to control the sound. However, for some applications (e.g. with small volumes of water and the correct higher levels of surfactant) it may not be necessary to turn the sound field off entirely whilst the bubbles travel down the stream, and other implemetations may be used, e.g. switching the sound to much higher frequencies.
Preferably, the body includes a rear wall on which the acoustic transducer is mounted and a substantially conical element extending forwardly therefrom to form a relatively small radius end thereof communicating with the outlet, the rear wall and the substantially conical element defining a substantially conical chamber of decreasing radius extending from the transducer towards the outlet. The substantially conical element may be geometrically conical, or alternatively may have a non-geometric shape, such as being horn-shaped or bell shaped. The substantially conical element may be formed, for example, of cellular foam or rubber. Other materials may be employed. The choice of material is determined by the requirement to match (as closely as practicable) the acoustic wall boundary conditions within the cone to those in the nozzle and liquid stream once it leaves the nozzle, so as to avoid sharp impedance mismatches between cone, nozzle and liquid stream that would hinder the passage of acoustic energy along the stream.
Furthermore, a design principle employed by the chamber and nozzle used in the preferred embodiments of the present invention is that the acoustic boundary condition on the inner wall of the chamber and nozzle should match the acoustic boundary condition that will occur in the stream of liquid once it leaves the nozzle. The embodiments disclosed herein produce a stream of liquid in free air, and hence the inner wall of the chamber needs to be pressure-release, and so a pressure-release material such as cellular foam or rubber has been used to provide such a pressure-release boundary. If, however, in accordance with an alternative embodiment of the present invention a cleaning jet of liquid (e.g. water) was not directed into air but instead squirted into another article to be cleaned, for example up a pipe, e.g. for cleaning an endoscope of narrow internal diameter, that embodiment would use a chamber with an internal wall condition matched to the respective acoustic boundary condition of the article, and a pressure-release characteristic may not be required.
The apparatus may further comprise an inlet manifold which comprises a plurality of inlet passages each connected at an inlet end to the inlet and at an outlet end to the body and/or an acoustic isolation device in the inlet.
The apparatus may also include a device for adding surfactant to the liquid.
The present invention further provides a method of cleaning a surface, the method comprising the step of: directing towards the surface a liquid flow from a nozzle, the liquid flow including acoustic energy and entrained gas bubbles within the liquid flowing out of the nozzle.
The surface may be an external surface or an internal surface, for example of a cavity. The liquid flow may be directed against the surface or into the vicinity of the surface, for example by squirting the liquid up the inside of a tube (e.g. an endoscope) or pipe, such as a drinks dispenser nozzle.
The method may further comprise the step of generating gas bubbles electrolytically within the liquid.
Preferably, the gas bubbles are generated within or at a distance from a free end of the nozzle. For example, it was found that if the gas bubble generator, e.g. electrolytic wires generating the gas bubbles, was positioned a small distance, such as about 1 cm, from the nozzle tip, the stability of the fluid stream was increased.
Preferably, the gas bubbles are generated intermittently.
The method may further comprise the step of generating pulses of the acoustic energy. Furthermore, the acoustic energy within the pulses may be frequency or amplitude modulated.
Preferably, the liquid flow impacts the surface with waves of bubbles and pulses of acoustic energy which substantially simultaneously reach the surface.
Preferably, the acoustic energy is introduced into the liquid by an acoustic transducer as the liquid flows through a substantially conical chamber of decreasing radius extending from the transducer towards the nozzle.
Such a conical chamber is not essential, and other chamber shapes, for example of constant cross-section, formed by a body such as a cylindrical pipe, may be used in certain applications.
Preferably, a liquid input flow into the chamber is divided into a plurality of parallel flows by an inlet manifold which comprises a plurality of inlet passages each connected at an inlet end to the inlet and at an outlet end to the chamber.
The method may further comprise acoustically isolating an inlet conduit of the chamber from the acoustic transducer.
The present invention further provides a method of cleaning a surface, the method comprising the step of providing gas bubbles at the surface and employing modulated acoustic energy to generate surface waves in the bubbles to cause non-inertial collapse of the bubbles.
Preferably, the bubbles and acoustic energy are in a liquid flow directed towards the surface.
Typically, the surface includes at least one cavity, recess or pore and the bubbles are dimensioned to be able to enter at least one cavity, recess or pore. Preferably, the acoustic energy excites the surface of the bubbles when the bubbles are located in the at least one cavity, recess or pore.
Preferably, the bubbles and acoustic energy are directed to the surface as pulses so that the pulses of bubbles and acoustic energy are incident on the surface substantially simultaneously.
The present invention is at least partly predicated on the finding by the present inventors that when ultrasonic cleaning is carried out, it is not necessary for cleaning that inertial cavitation is generated. The preferred embodiments of the present invention provide a cleaning apparatus adapted to achieve surface cleaning (decontamination) by the employment of bubble action on a surface (or within a crevice within a surface) driven by acoustic stimulation. This avoids inertial collapse at the interface and hence the associated parasitic erosion mechanisms of known ultrasonic cleaning systems and methods. However, it is possible optionally to generate inertial cavitation in accordance with some embodiments of the present invention if the surface to be cleaned is sufficiently robust.
Without being bound by theory, it is believed that in accordance with the preferred aspects of the present invention, the motion of the bubble process is dominated by the pressure within the gas phase which results in non-inertial cavitation, rather than the converging inertia of the liquid which results in inertial collapse. The cleaning can be further enhanced by the establishment of surface waves on the bubble wall (also sometimes referred to as bubble shape oscillations). Therefore the apparatus and method of the present invention are preferably adapted to produce bubbles remote from, but close to, the solid/liquid interface of the object to be cleaned and then to drive them against that surface with an appropriate sound wave sufficient to produce non-inertial collapse and, if applicable, surface waves on the bubble wall.
However, as described above, for some particularly robust surfaces inertial collapse may additionally be achieved at the surface which may provide enhanced cleaning without excessive damage to the surface. A further feature of the preferred embodiments of the present invention is to deliver such cleaning ability, using non-inertial cavitation, through a liquid stream or hosepipe/tap output, which avoids the need for immersion, and so makes the apparatus portable. This may be achieved by a suitable adaptation of exisiting cleaning systems which currently use hosepipes or taps to deliver a flow of cleaning fluid. Such an apparatus of the preferred embodiments of the present invention system may also conserve water and/or power compared to a known immersion system.
The preferred embodiments of the present invention can provide apparatus and methods which employ a novel application of the excitation of gas bubbles within liquids with the ultimate aim of surface decontamination. Substantially any surface may be cleaned in accordance with the invention, ranging from internal or external surfaces, hard or soft surfaces, inorganic objects (e.g. an endoscope), organic or living bodies, including foodstuffs, (e.g. wrinkles on a lettuce), the human skin (e.g. under the fingernails of a surgeon), using portable or fixed hoses and taps (e.g. for forensic, autopsy, archaeological examinations). The surface for decontamination might include buildings, facilities, infrastructure (e.g. abattoirs, hospital wards, surgeries), and associated objects contained within those (personnel, keyboards, telephones etc.), or used outside. In particular, those apparatus and methods employ targeted excitation of bubbles at the surface of an interface or within a pore, cavity, recess, crevice, pipe, tube or chamber. These bubbles have been shown to do useful work including the cleaning the surface, pore, cavity, recess or crevice within the surface, or cleaning in a pipe, tube or chamber. As such this represents a new and powerful method to clean a wide variety of surfaces.
In particular, the present invention is at least partly based on the findings by the present inventors that surface cleaning may be achieved through the generation of bubble oscillation (including surface waves) driven by appropriate acoustic excitation. Also, crevice cleaning may be achieved through bubble capture into pores and other surface features, including, but not restricted to, capture through processes of flow, hydrodynamic effects, or acoustic radiation forces. These bubbles oscillate and remove material from the crevice. The acoustic excitation of these events may be achieved along a flowing stream of liquid. Bubble population effects may be harnessed to allow transmission of sound down through the liquid to the surface to be cleaned. The flow apparatus, geometry, materials and acoustic characteristics of the bubble population may allow efficient acoustic transfer to the surface to be cleaned. Relatively low flow rates may be deployed, minimising cleaning solution wastage.
As an additional preferred mechanism to generate bubbles, electrochemical bubble seeding technology has been developed and exploited. Pulsed bubble generation (creating a bubble swarm) in tandem with pulsed acoustic excitation may generate 'active' bubbles on the surface to be cleaned. An amplitude or frequency modulated sound field, coupled with the acoustic energy optionally being switched on and off, may be employed to maximise the acoustic pressure delivered by the apparatus to the interface in the presence of a suitable bubble swarm. Pulsed bubble generation and pulsed acoustic excitation may be independently controlled so that at the nozzle bubble generation is independent of the generation of a pulse of the acoustic excitation, and such independent control can vary the bubble pulses and the acoustic energy pulses independently so that at the surface to be cleaned the bubbles and the acoustic energy pulse can be incident on, or in the vicinity of, the surface substantially simultaneously to enable efficient cleaning of the substrate by the acoustic energy causing non-inertial cavitation of the bubbles at or in the vicinity of the surface.
Such pulsing of the acoustic energy does not need necessarily to turn the sound field off between pulses, but instead may modulate the acoustic energy, by amplitude or frequency modulation, it to provide high energy acoustic pulses separated by low energy background.
In some embodiments, the sound is turned off as the bubble swarm travels down the stream (to prevent acoustically-induced bubble coalescence), and then the sound is turned on to provide a modulated acoustic energy pulse once the bubble swarm reaches the surface to be cleaned. Once these bubbles have undertaken some cleaning and started to disperse in the flow, the sound is turned off and another swarm of bubbles is generated at the nozzle and the process is repeated. The independent control can be achieved by taking into account the fact that sound travels down the liquid stream at a different speed to the bubbles. The timing of the current supplies used to generate bubbles and sound is such as to ensure both bubble swarm and ultrasound arrive at the surface at the same time. Given this criterion, the different transit times of bubbles and sound down the tube dictate the timing for the activation of the currents which generate sound and bubbles, such that their activations may be staggered if the timing so dictates. The underlying technical concept is to utilise their different transit times down the liquid stream to ensure that the bubbles and acoustic energy occur at the same time at the surface which is to be cleaned.
In addition, novel electrochemical techniques may be used to monitor the degree of in situ cleaning as a result of fluid flow and bubble action on the surface. The invention may also include apparatus for monitoring the efficacy of the cleaning through the use of sensors close to the location where the surface to be cleaned is to be placed, or embedded in that surface.
Accordingly, the cleaning apparatus may further comprise a device for monitoring the cleaning of the surface, the device comprising first and second electrodes, forming an electrochemical cell, adapted to be respectively located at a portion of the surface and interconnected by a resistance measuring apparatus.
The present invention further provides a method of monitoring the cleaning of a surface, the apparatus comprising locating first and second electrodes, forming an electrochemical cell, at respectively portions of a surface to be cleaned and measuring the resistance therebetween.
Typically, the first electrode is located in a cavity, recess or pore to be cleaned and the second electrode is located on an external portion of the surface.
Preferably, the method comprises determining a decrease in the resistance to indicate cleaning of the cavity, recess or pore. For the apparatus of the preferred embodiments of the present invention, the nozzle material and shape, and the driving acoustic frequency, may be chosen such that at least one mode is not evanescent in the liquid stream. The nozzle may be designed to prevent a strong impedance mismatch between the sound field in the conical body and the sound field in the liquid stream. For some applications (for example if the liquid stream is surrounded by gas once it leaves the nozzle) a specific (but not exclusive) preferred manifestation of this is in use of materials which are exactly (or nearly) pressure-release in the construction of the nozzle and/or conical body. The flow rate and nozzle design may be chosen so that the liquid stream does not lose integrity before it reaches the target surface to be cleaned (e.g. break up into drops, entrain unwanted bubbles, etc.) to the extent that it hinders the transmission of sound from the nozzle to the target. The shape of the conical body may be designed to assist the transmission of sound from the cone to the liquid stream and subsequently through the nozzle. An amplitude or frequency modulated sound field may dramatically improve pressure transmission within the fluid flowing through the apparatus to the target substrate.
Embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which:
Figure 1 is a schematic side view of a cleaning apparatus in accordance with a first embodiment of the present invention;
Figure 2 is a schematic side view of a cleaning apparatus in accordance with a second embodiment of the present invention;
Figure 3 is a schematic perspective view of a cleaning apparatus in accordance with a third embodiment of the present invention;
Figure 4 is a schematic view of an alternative shape for the cone for use in any of the embodiments of the cleaning apparatus of the present invention;
Figure 5 is a schematic representation, as a side view, of a sequence of steps in a cleaning cycle showning the generation of acoustic energy pulses and gas bubble pulses producible by any of the embodiments of the cleaning apparatus of the present invention;
Figure 6 shows the phase relationship between (a) acoustic energy (sound) generation and (b) bubble generation, to provide the pulses, with respect to time at the nozzle in any of the embodiments of the cleaning apparatus of the present invention, and additionally shows the acoustic energy modulation;
Figure 7 shows the acoustic pressure signal recorded at the target surface for a modulated and unmodulated pressure sequence using the duty cycle shown in Figure 6;
Figure 8 shows the relationship between pressure and time, measured at a hydrophone, generated by the acoustic energy, either in continuous or modulated mode, in the cleaning apparatus of any of any of the embodiments of the present invention; and
Figure 9 shows the relationship between resistance and time, measured at a surface, either clean or unclean, for use in a method of monitoring the cleaning of a surface according to an embodinment of the present invention.
Referring to Figure 1, there is shown a cleaning apparatus in accordance with a first embodiment of the present invention.
The cleaning apparatus, designated generally as 2, comprises a hollow body 4 defining a central chamber 6. The body 4 has a rear wall 8 and a substantially conical element 10 extending forwardly away therefrom which terminates in a forwardly-located orifice 12. Typically, both the element 10 and the wall 8 are rotationally symmetric, i.e. circular, although other geometric shapes may be employed. In this specification the term substantially conical" should be interpreted broadly to encompass structures which are not only geometrically conical, but also structures which for example are bell-like, having a concave inner wall as seen from inside, as shown in Figure 1, or have a constant half-angle as shown in Figure 2, or are horn-like as shown in Figure 4 (i.e. has a convex inner wall as seen from the inside). Accordingly, the element 10 forms a conical body such as a bell- or horn-like structure, and for brevity may be referred to hereinafter simply as a ,,horn".
A nozzle 14 extends forwardly from the orifice 12 and defines a liquid outlet 16. A liquid inlet 18 is located at or adjacent to the rear wall 8. A liquid supply conduit 20, typically in the form of a flexible hose, communicates with the inlet 18. An acoustic transducer 22 is mounted on the rear wall 8. A controller 23 controls the operation of the transducer 22. Typically, the transducer 22 is mounted on an outer surface of the wall 8 and extends over a substantial proportion of the surface area of the wall 8. Alternatively, the transducer may be embedded into the chamber on or through the rear wall. Indeed to achieve a pressure-release condition in the chamber walls (e.g. the stream was to be squirted into a cavity, such as into the internal bore of an endoscope) then the appratus may employ either a rear-wall transducer or alternatively make the inner surface of the horn comprise a transducer. It should be noted that the transducer could be mounted elsewhere such as on the walls of the horn or the nozzle, providing that it was not required, for the particular application, to match to a pressure-release boundary condition once the stream has left the nozzle (e.g. if the stream was being used to clean the inside of an endoscope).
In use, liquid flows continuously through the supply conduit 20 into the central chamber 6 and then outwardly through the outlet 16 of the nozzle 14 to form a stream 24 of liquid which is directed against the surface 26 of a substrate 28 to be cleaned. The surface 26 may, in particular, be provided with three dimensional surface features, such as a crevice 30 shown in an exaggerated form in Figure 1.
A bubble generator 32 is located within the nozzle 14 upstream, in the direction of fluid flow, from the outlet 16. The bubble generator 32 generates gas bubbles within the liquid stream so that the liquid stream impacting on the substrate surface 26 includes not only acoustic energy from the transducer 22 but also gas bubbles.
There are several options for seeding gas bubbles into the liquid flow, including gas injection and in situ electrochemical gas bubble generation by electrochemical decomposition of water in the liquid. For in situ electrochemical gas bubble generation, the incorporation of electrodes into the structure allows controlled seeding, and is preferably achieved by threading 50-100 [mu]m diameter Pt wires through the nozzle of the jet (~ 1 cm before the exit). Other options including use of one or more electrodes in the liquid flow, or in the wall of the nozzle.
Referring to Figure 2, in this modified embodiment, the rear wall 40 consists of a plate, for example of plastic or a metal such as aluminium or stainless steel, having the liquid inlet 42 therein and the acoustic transducer 44, which may itself incorporate a truncated cone 46 is bonded or otherwise held on to the rear surface of the plate 40. The substantially conical element 48, comprising a horn, extends forwardly of the plate 40 and forms an integral nozzle 50 at which the bubble generator 52 is located.
In the embodiment of Figure 1 the hollow body 4 may be made integral and made of a single material, with the rear wall 8 being integral with the horn 10. In this embodiment, the horn is composed of material that can function as a pressure release interface when fluid is directed thereagainst, so that acoustic energy in the material of the horn is effectively and efficiently transmitted into the flowing liquid at the inner surface of the horn. The aim of the apparatus of this embodiment is to introduce acoustic energy into the flowing fluid stream and then to direct that stream through the outlet onto the surface to be treated by using the conical shape of the horn to concentrate both the acoustic energy and the fluid flow while minimising acoustic losses or frictional loses against the conical surface.
The embodiment discussed above is directed to the specific application of introducing sound energy into the liquid stream when the liquid is surrounded by air after leaving the nozzle. That is applicable, for example, for cleaning under a surgeon's fingernails or cleaning a letttuce. However for other applications in which the liquid stream is directed into the article to be cleaned (such as cleaning up an endoscope) the liquid stream on leaving the nozzle may not have a pressure-release boundary condition, and for that embodiment a horn made of different, non-pressure release, material may be employed.
The nozzle and the outlet are shaped and dimensioned to allow for acoustic transmission along the fluid stream. It is advantageous to form a smooth flow of the stream. It is well within the abilities of a person skilled in the art to produce a suitable combination of shape and dimensions for the horn, the outlet and the inlet to achieve the desired smooth flow of liquid containing acoustic energy from the transducer.
As described above, novel electrochemical techniques may be used to monitor the degree of in situ cleaning as a result of fluid flow and bubble action on the surface.
In this embodiment, the cleaning apparatus further comprises a device for monitoring the cleaning of the surface, the device comprising first and second electrodes 200, 202, forming an electrochemical cell, adapted to be respectively located at a portion of the surface and interconnected by a resistance measuring apparatus 204. In the method of monitoring the cleaning of the surface, the first electrode 200 is located on an external portion of the surface and the second electrode 202 is located in a cavity or recess to be cleaned. The resistance therebetween is measured using the resistance measuring apparatus 204 to determine a decrease in the resistance to indicate cleaning of the cavity or recess. As show in Figure 9, an initial resistance value A changes according to value B by decreasing significantly when the monitored surface portion has been cleaned.
In this aspect of the invention, electrochemical cleaning measurements under the tip of the ultrasonic horn, using either flat, recessed or cannular electrodes, made use of an electrochemical cell consisting of two or more electrodes. The cleaning liquid acted as an electrolyte. The resistance of the fouled working electrode was monitored such that when the cavity or recess was unclean, the working electrode would have no or only poor electrical contact with the liquid electrolyte and so a relatively high resistance would exist between the two electrodes, whereas when the cavity or recess was cleaned and therefore the working electrode came into contact with the solution, a at low resistance would be measured. This provides a very effective method for quantifiably measuring the cleaning time. This method relies on the measurement of the uncompensated resistance of the system.
Therefore, if the uncompensated resistance of the system can be monitored as a function of time, it is possible to use this method to detect the cleaning of the cavity, recess or pore. This method is able to give quantifiable data on the cleaning of the cavity, recess or pore. In order to remove the effect of capacitance of the electrode a low amplitude high frequency (100 kHz, 200 mV zero to peak amplitude) alternating voltage signal was applied between the working electrode (for example a 0.5 mm diameter Pt recessed electrode) and reference electrode (normally a large piece of metallic material, for example a Cu plate). The current passed can then be used directly to determine the resistance of the system as a function of time. Using this system the only chemical required is a supporting electrolyte to make the solution conducting such as potassium chloride (KCl) or common salt (NaCl) both of which are relatively cheap and easy to dispose of. This method is used to monitor the cleaning of a surface with a variety of features designed to investigate the efficiency of targeted ultrasonic cleaning.
If the monitoring component is not needed for a particular application when carrying out the cleaning method of the invention, and only cleaning is required, then an electrolyte such as KCl or NaCl or equivalent is not necessary within the cleaning liquid.
Referring to Figure 3, in an alternative embodiment, the inlet conduit 60, in the form of a hose, is connected to a manifold 62 which divides the inlet liquid flow into a plurality of different inlet flow passages each in a respective secondary inlet conduit 64, each secondary inlet conduit 64 connecting the inlet conduit 60 to a respective inlet 66 on the rear wall 68 conected to the horn 70. The assembly of the rear wall 68 and the horn 70, and the manifold 62, may be connected together within a common housing 72. The horn 70 is connected to an outlet 74.
Referring to Figure 4, an alternative shape for the horn 80 is disclosed, in which the horn 80 has a cylindrical downstream portion 82 and a hyperboloidal (or some other horn- shape, such as parabolic, catenoidal, etc.) outwardly flaring upstream portion 84.
It may be seen from all of Figures 1 to 4 that various different shapes of configurations for the horn may be employed, provided that the horn is shaped to provide a constant fluid flow outlet minimising both loss of acoustic energy and frictional losses. This would provide optimal acoustic and flow properties in the stream of fluid which impacts the surface to be cleaned. Furthermore, such a horn-shaped structure is not essential for some applications and the chamber may have any other shape, and be defined by any material of the body, that permits acoustic energy to be introduced into the fluid flow and exit from a nozzle.
If the liquid stream is to flow through gas on leaving the nozzle, and therefore the inner walls of the horn need to be pressure-release, then a particularly preferred material for the horn is a cellular foam material or a rubber which can avoid an impedance mismatch between the sound field in the horn and the sound field in the liquid stream flowing therethrough. The flow rate and nozzle design are selected so that the liquid stream does not lose integrity before it reaches the surface to be cleaned. The shape of the horn is designed to assist the transmission of sound from the horn to the liquid stream flowing through the nozzle. For example, when the horn is a cellular foam material the horn is formed by moulding a conical cavity within a solid foam block (although other manufacturing processes, such as cutting from a block, may be used).
Most typically, the horn and nozzle are rotationally symmetric.
In any of the embodiments, the inlet may be provided with an acoustic isolation device which prevents acoustic energy being transmitted back along the liquid supply conduit 20. The acoustic isolation device, shown schematically as 25 in Figure 1, may comprise an acoustic filter, optionally having a selected frequency range, and/or a venturi narrowing in the conduit 20, and/or an expansion chamber, and/or by control of the diameter of the conduit to provide that the driving frequency is below the cut-off frequency of all modes for the inlet (as would happen for sufficiently small-bore manifold inlets made of pressure-release material).
In these embodiments, the apparatus size can be varied to provide varying volumes of the liquid stream. Smaller or larger volumes can be achieved by scaling the flow rate, nozzle size and the driving acoustic frequency, in line with the provision that at least one mode is not evanescent in the liquid stream, thereby to provide a cleaning solution stream impacted onto the surface accompanied by a suitable sound field and active bubbles. This mode may be the plane wave mode if the acoustic boundary conditions at the wall allow. In order to achieve the required volumetric flow rate, as well as enabling the flow to project to a sufficient distance beyond the free end of the nozzle, a small outlet aperture is required. Except for the plane wave mode (if the acoustic boundary conditions permit it to propagate, which is not the case if the liquid stream flows through air), then for each mode the sound transmission down the liquid jet will be undesirably restricted below a characteristic "cut-off frequency (Fco). If the stream were to be passed into a solid tube, such that solid wall would surround the stream, then the lowest frequency mode would be plane wave and there would be no cut-off frequency for that mode, although higher order modes would have their own cut-off frequencies. In the particular case where the liquid stream flows through a gas space on leaving the nozzle, then the boundary condition at the curved walls of the stream would be pressure-release, and for such a condition the cut-off frequency (Fco) for the lowest mode is calculated according to the equation
Fco = 2.4048c (Equation 1)
2[pi]a where c represents the velocity of sound in the fluid and a represents the liquid stream radius. For example, for a flow outlet of around 10 mm internal diameter, and assuming a speed of sound in the liquid of 1500 m/sec, the cut-off frequency of the liquid stream for the lowest mode would be on the order of 114 kHz (modes of higher order would have higher cut-off frequencies). However, fluid properties and any entrapment of bubbles, as discussed hereinafter, would affect this cut-off frequency. Bubbles, for example, may reduce the sound speed in the liquid, and hence reduce the cut-off frequency of the mode.
The bubble generator 32 is adapted to generate gas bubbles which are then acoustically excited and impact on the surface to be cleaned. The bubbles are driven into oscillation by the acoustic energy and can get into crevices and pores on the substrate to be cleaned, so that they effectively clean the substrate surface.
The bubble generator 32 may act directly to inject gaseous bubbles into the fluid flow, for example through a needle, the needle optionally vibrating. Other options for bubble generation include through use of cavitation (hydrodynamic or acoustic) or free-surface bubble entrainment, or chemical gas production, or by a more preferred route of electrochemical in situ generation of gas bubbles by electolytic decomposition of the water in the liquid flow. The bubble generator 32 adapted for electrochemical bubble generation comprises an electrode comprising an array of electrically conductive wires, for example platinum wise having a diameter of 50 [mu]m, extending across the outlet. The electrode is connected to a source of electrical energy (not shown) and, when electrically powered, the electrical energy electrolytically decomposes water in the fluid flow to generate streams of bubbles of both oxygen and hydrogen gas which are entrained in the flowing fluid and directed towards the target surface to be cleaned.
Figure 5 shows a sequence of steps in a cleaning cycle for a respective bubble swarm.
As shown in Figure 5 (a), the bubble generator is controlled by a controller 98 so that bubbles are formed intermittently to form intermittent swarms 100 (or waves) of bubbles which successively impact against the surface 102 to be cleaned. When the bubbles impact the surface 102 to be cleaned, the bubbles are driven to oscillate by the acoustic energy, thereby penetrating crevices which are cleaned by the acoustic energy.
As also shown in Figure 5, the amplitude or frequency modulated acoustic energy from the transducer is pulsed intermittently. This produces pulses of acoustic energy, which interact with the intermittent bubble swarms 100 described above, in a concerted manner.
Figure 5(b) shows that when the acoutic transducer is switched off, the bubble swarm 100 travels downstream together with the liquid flow directed towards the surface 102. The bubble swarm 100 reaches the surface 102, as shown in Figure 5(c). Figure 5(d) shows that as the bubble swarm 100 reaches the surface 102, the acoustic transducer is switched on, to generate a sound field pulse, optionally amlitude or frequency modulated, which is transmitted towards the surface 102 at the speed of sound through the liquid. The acoustic energy of the pulse activates the bubbles of the swarm at the surface 102 to effect enhanced cleaning, by non-inertial collapse of the bubbles at the surface, and optionally generating surface waves in the bubbles, and/or optionally causing higher energy cleaning events (e.g. inertial collapse of bubbles, jetting etc.). This completes a cleaning cycle for a single bubble swarm. A next cleaning cycle for a subsequent bubble swarm is then initiated by generation of the subsequent bubble swarm as shown in Figure 5 (a).
As shown in Figure 6, at the nozzle there is a particular phase relationship between the generation of the sound pulse and the generation of the pulse of bubbles. The phase relationship changes as the sound and bubbles are transmitted away from the nozzle through the liquid since the acoustic energy and the bubbles are transmited at different velocities through the liquid towards the surface to be cleaned. The aim is to provide a phase relationship, which typically involves a delay time td betwen bubble generation and generation of the pulse of the acoustic energy, so that the acoustic energy and the bubbles reach the surface to be cleaned in phase and at the same time. In the example illustrated, a delay time td is provided which would vary with flow rate and distance to the target.
In this embodiment the sound is turned off during bubble generation and bubble transfer to the surface to be cleaned. The excitation of these bubbles is intermittent, and in synchronism with the intermittent on/off nature of the electrochemical bubble generation. In the embodiment of Figure 6, the bubbles may be generated for a generation period, typically 10 milliseconds, with a periodicity of 100 milliseconds. After the termination of each bubble generation, there is a delay, typically 30 milliseconds, after which the sound is turned on (or, in other embodiments, modulated to provide a high energy pulse) for a period of 60 milliseconds. The sound is then turned off and simultaneously the bubbles are turned on, in a subsequent cleaning cycle.
These values apply to one particular device, but would be longer or shorter if the device was larger or smaller in size respectively. This delay is flow rate and distance dependant. It can be variable and, for example, if a long pipe (endoscope) is the cleaning target, the delay can be varied to achieve cleaning at different positions along the liquid flow direction.
Within each acoustic energy pulse, the acoustic energy is amplitude or frequency modulated, as also shown in Figure 6 (amplitude modulation being exemplified by varying the driving voltage of the transducer). The modulation period, which is frequency dependent, is typically 1 millisecond.
As shown in Figure 7, the pulsed generation of such bubble swarms causes modulated pressure to be applied to the cleaned surface by each bubble swarm when the respective bubble swarm impacts the surface to be cleaned. Such modulated presssure typically occurs every 100 milliseconds. As explained earlier, each bubble swarm is oscillated by the acoustic energy which produces a cleaning effect.
Figure 8 shows pressure at a hydrophone for a constant drive acoustic field, either in continuous mode or modulated mode. As shown by Figure 8, when a constant acoustic energy impacts on the surface, the pressure generated at the surface is relatively low and constant, whereas when modulated waves of acoustic energy impact the surface, the maximum energy released at the surface by each wave is significantly greater.
Therefore by employing pulsed bubble generation and pulsed generation of acoustic energy in a coordinated manner, bubbles are excited at the surface so that bubbles are present at the surface when the acoutic energy is also at the surface, and furthermore the cleaning impact achieved by both the bubbles and the acoustic energy is increased by additionally providing that the acoustic energy is amplitude or frequency modulated at a higher frequency that the pulses, greatly improving cleaning efficacy. The presence of a bubble swarm formed between a pair of acoustic energy pulses separates those acoustic energy pulses. Each bubble swarm is independently impacted on the surface to be treated and independently excited by the acoustic energy of the succeeding acoustic energy pulse.
In accordance with a further aspect of the apparatus and method of the present invention, it has been found that the addition of a surfactant to the liquid can afffect the bubble size achievable without bubble coalescence. Sufficient surfactant may be added, if necessary, to prevent coalescence of bubbles as they flow down the stream if, without surfactant, such coleascence produces bubbles too large for approprite cleaning; but not so much surfactant that the bubbles are too small for cleaning when they reach the site. The following Table 1 shows how the bubble size (estimated from high-speed camera experiments) is affected by the surfactant loading, and how the activity, defined as erratic bubble motion across a surface, which is indicative of bubble oscillation by acoustic energy, varies with bubble diameter.
The range of total surfactant volume of from 150 to 750 [mu]l to give a surfactant concentration of from 0.003 to 0.015 % by volume resulting in a bubbble diameter of from about 40 to 45 [mu]m provided the conditions where highest cleaning activity was observed. The particular total surfactant and surfactant concentration values to achieve the desired bubble activity may be dependant on the type of surfactant employed.
Without being bound by any theory, nevertheless the present inventors have found that a number of phenomena are relevant to achieving effective ultrasonic cleaning.
First, when bubbles were observed within a pore, cavity or crevice of a surface to be cleaned, the bubbles were noted to oscillate in the ultrasonic field, and such oscillation is believed to play a key role in the decontamination of these more complex surfaces. Athough such pulsation oscillations may have a cleaning effect, the present invention is additionally, and importantly, predicated on using surface waves on the bubble wall to provide a cleaning effect. Second, it was found that the sound field plays an important role in trapping bubbles in such a pore, cavity or crevice, because although bulk flow can transport bubbles from one region of the liquid towards the solid surface, the acoustic excitation causes the additional benefit of attracting the bubble into the crevice and trapping it there by radiation forces, and furthermore of inducing net size increase of appropriate bubbles in pores though degassing and rectified diffusion. As such, the use of acoustic fields offers a significant advantage over the use of flowing liquid alone.
Of course, ultrasonic cleaning has been in use for many years in 'ultrasonic cleaning baths', whereby inertial cavitation and the generation of high speed liquid jets through bubble involution causes the removal of surface contaminants.
However, in accordance with the preferred aspects of the present invention and as found by the inventors in their experimental studies, the cleaning does not occur as a result of such a bubble phenomenon, which in normal room conditions requires zero-to-peak acoustic pressures of order 1 bar in order to cause inertial cavitation, but instead, lower amplitude acoustic fields are used to generate non-inertial bubble pulsations and optionally surface waves on the walls of some bubbles. It is these surface waves and the associated liquid motion which is utilized in the pore cleaning employed in the preferred aspects of the present invention. However, the present invention further provides that, in addition to cleaning using non-inertial cavitation, inertial cavitaion can additonally be achieved as well as non-inertial cavitation to put the power of a cleaning bath, which would include inertial cavitation and jetting, onto the end of a hosepipe stream of water and clean from a distance (e.g to power clean the nooks and crannies of an aircraft engine that cannot be immersed in a cleaning bath or to decontaminate a hospital ward). That is an immensely powerful cleaning method.
As discussed further below, the invention can nevertheless be modified additionally to provide such inertial collapse on particularly robust surfaces.
In accordance with the preferred aspects of the present invention, the bubbles are independently generated at a location remote from the surface to be cleaned, driven towards the surface to be cleaned within a fluid flow, and excited by acoustic energy at the surface so as to provide enhanced cleaning efficacy over the surface, particularly when the surface has a three dimensional characteristic, including pores, recesses, cavities or crevices, and inside pipes and tubes.
In accordance with the preferred aspects of the present invention, a sufficient acoustic pressure amplitude is developed at the surface in question without the requirement for generation of inertial collapse on the interface, although the invention can be modified additionally to provide such inertial collapse on particularly robust surfaces. This will drive surface waves and suitable bubble oscillation to clean the interface and associated structure without causing the damage and erosion which can potentially occur when inertial cavitation or the generation of high-speed jets through bubbles are excited very close to or at a solid surface. Any bubble entrapment into crevices aids cleaning: the sound field used in the embodiments aids transport of bubbles from the bulk liquid to the target surface, and then attracts suitable bubbles into the crevice as a result of acoustic radiation forces. Having been trapped in the pore, these bubbles effectively empty/clean the cavity in question. A sufficient bubble population should be provided or delivered to the surface of the materials for cleaning. This is to enable bubble excitation at the solid/liquid interface driven by the targeted acoustic field of the apparatus in question.
Considering the acoustic transmission for a flow system, it is desirable to match the boundary conditions at the nozzle (and horn) with those in the stream once it has left the nozzle. In the specific example where the liquid stream passes through a gas space on leaving the nozzle, it is desirable to achieve a pressure release condition over the walls of the flow system and to operate above the 'cut off frequency of at least one mode (which cannot be the plane wave mode because this mode is evanescent at all frequencies for pressure-release walls), and that cut-off frequency being determined by the aperture, but is different for each mode even though all have the same aperture. However, the plane wave mode (which cannot propagate in a liquid stream flowing through gas but can propagate down an enclosed tube) can exist at all frequencies in a rigid walled tube. It has been found that sound transmission down a suitable liquid stream can be facilitated in several ways. First, the frequency of the sound field applied is chosen to be greater than the cutoff frequency of at least one propagating mode (preferably more) for acoustic propagation along the liquid stream. Second, bubble induced perturbation of the system can enable sound transmission through the liquid stream. Third, amplitude or frequency modulated sound can be used to increase acoustic pressure at the surface of the object to be cleaned and hence achieve bubble oscillation.
The flow rate and nozzle design are preferably chosen so that the liquid stream does not lose integrity before it reaches the target (e.g. break up into drops, entrain bubbles etc.) to the extent that it hinders the transmission of sound from the nozzle to the target. Symmetrical nozzle designs and low flow rates are one preferred way of achieving this objective. Although the chamber upstream of the nozzle is, in the preferred embodiments, substantially conical in shape, in other embodiments the chamber may ave a different shape provided that the acoustic energy is imparted into the liquid flow at the desired boundary condtition for the particular cleaning application.
Preferably, the apparatus is adapted electrochemically to generate a swarm of appropriately sized bubbles, and then to transfer that swarm, through the fluid flow in the stream, to the surface to be cleaned in the absence of acoustically driven bubble coalescence. Then, the acoustic energy is provided to acoustically excite motion/surface waves on the bubbles in the swarm at the target substrate.
The seeding of bubbles into the flow assists cleaning by: perturbing the system to facilitate sound transmission into the liquid stream; perturbing the sound speed to facilitate sound transmission into the liquid stream; perturbing the acoustic impedance in the liquid to facilitate sound transmission into the liquid stream; perturbing the fluid loading to facilitate sound transmission into the liquid stream; providing bubbles which are transported to the target where those bubbles undertake cleaning; and addition odf surfactant to the liquid which can affect the achievement of a stable bubble diameter without bubble coalescence.
The preferred embodiments of the present invention can provide enhanced cleaning of items or objects such as, for example, surgical equipment and prostheses, tools, product components (e.g. microchips), foodstuffs, packing, moulds, materials and packaging for pharmaceuticals, laboratory equipment, and forensic equipment. Infrastructure and facilities (e.g. hospitals ward rooms and their keyboards, telephones; abbatoirs; nuclear and chemical dacilities etc.) and personnel (e.g. under fingernails for surgeons, for cleaning of personnel or vehicles contaiminated by biologial, chemical or nuclear hazard etc.) are also suitable applications.
Examples of items which would particularly benefit from the 'liquid stream' manifestation of the preferred embodiments of the present invention (e.g. fitted to a hose or tap) include: vehicles, domestic products (in the home and in the show-room or factory), human hands; optical lenses; surfaces with specialised and delicate coatings, e.g. Teflon (Registered Trade Mark) coatings on non-stick frying pans or optical coatings on lenses; and for cleaning (e.g. through biofilm removal) without damage of items before surgical implantation, such as implants, prostheses, organs, etc..
Such cleaning can be achieved without any abrasive particles, just a stream of liquid containing gas bubbles. Abrasion and damage degrade components and make subsequent contamination (e.g. growth of biofilms) more likely and furthermore make subsequent cleaning more difficult.
The portability and conservation characteristics of the cleaning apparatus of the preferred embodiments of the present invention make it particularly convenient for the decontamination and cleaning of buildings (or other facilities where the target cannot be immersed, or where it is preferably not to transport it to a specialist cleaning facility), either as part of the scheduled cleaning routine (e.g. for abattoirs, hospitals, factories etc.) or as a tool for the decontamination of large facilities (e.g. in the decommissioning of chemical and nuclear plants, or areas contaminated as a result of terrorist or military action).
A liquid stream technology as employed in the preferred embodiments of the present invention is particularly attractive for cleaning rooms, corridors, and fixed installations. Living material (personnel, animals) could also be decontaminated using this invention, where portability (or the incorporation of the invention into existing shower or hose facilities) eliminates the delay which would be incurred transporting a contaminated person to a non-portable decontamination facility.


this table setting from rebecca taylor is giving me holiday feels without a trace of the usual suspects. i like an unexpected holiday vibe. also how cute are the outfits in the story?
1. i don't know what i have in store for christmas dinner yet, but i know it's going to include creamed brussels sprouts.
2. this salad sounds like the perfect holiday salad. light and refreshing after the typical roast. it's also dead easy to put together.
3. lacroix hangover cures. uh. thank you.
4. stopped me in my tracks too. reeeaalllly look.
5. the 12 best christmas candles. this is my pick.
6. the size of these dahlias and mums.
7. made me laugh out loud.
8. homemade chocolate coffee face polish and coconut coffee body scrub. i'd love to receive these as gifts, wouldn't you?
9. i reeeeaaalllly want this cabinet. look at it open.
10. look at this georgian doll house. specifically you melissa.
11. and finally this. this right here is the best thing i've read in a while. so relatable. if you don't have time right now, i urge you to bookmark it for when you do. you'll be so glad you did.
we are re-watching the final season of downton abbey. it's just feels like the right thing to do.


Welcome to Newly Build Up Budget Airport Hotel Avatar. Hotel is Located Near main NH-8, National Highway in the street Number 1, of Mahipalpur, New Delhi. Airport Hotel Avtar is one of the Budget Airport Hotel having tariffs from Rs.800 (US $16) to Rs.2500 (US 50).
Airport Hotel Avtar is of the best Hotel build up by Avtar Group of Hotels in Mahipalpur. We welcome you the best budget hotel of 22 rooms property. Reservation as well as hospitality service/ room service in the hotel is now open to national and International Tourists.
Designed for both business and leisure travel, Airport Hotel Avtar is ideally situated in Indira Gandhi Int'l Airport; one of the city's most popular locales. With its location just 10.00 Km from the city center and 3.00 Km from the airport, this 2-star hotel attracts numerous travelers each year. For those of you who want to venture out, I.G.I Airport Metro Station, Indira Gandhi International Airport, Dhaula Kuan Metro Station are just some of the attractions available to visitors.
Airport Hotel Avtar offers impeccable service and all the essential amenities to invigorate travelers. For the comfort and convenience of guests, the hotel offers laundry service/dry cleaning, tours, airport transfer, Wi-Fi in public areas, business center.
Step into one of 30 inviting rooms and escape the stresses of the day with a wide range of amenities such as shower, in room safe, internet access – wireless (complimentary), television LCD/plasma screen, executive lounge access. Besides, the hotel's host of recreational offerings ensures you have plenty to do during your stay. Enjoy unparalleled services and a truly prestigious address at the Airport Hotel Avtar.


How do you find the best mentor for you?
Mentors have been essential for me. No matter how many books you read or how much time you spend researching on the web, mentors are still a crucial part of learning in any arena.
So how do you find a great one?
…one who focuses his efforts on keeping you comfortable and happy, on making things go smoothly, with a minimum of effort… This is a good person to have as your waiter in a restaurant, but a terrible person to have as your teacher, coach, or mentor.
Watches you closely: He is interested in figuring you out— what you want, where you're coming from, what motivates you.
Is action-oriented: She often won't want to spend a lot of time chatting— instead, she'll want to jump into a few activities immediately, so she can get a feel for you and vice versa.
Is honest, sometimes unnervingly so: He will tell you the truth about your performance in clear language. This stings at first. But you'll come to see that it's not personal— it's the information you can use to get better.
Most great teachers / coaches / mentors do not give long-winded speeches. They do not give sermons or long lectures. Instead, they give short, unmistakably clear directions; they guide you to a target…Teaching is not an eloquence contest; it is about creating a connection and delivering useful information.
But another trait seemed to matter even more. Teachers who scored high in "life satisfaction"—reporting that they were very content with their lives—were 43 percent more likely to perform well in the classroom than their less satisfied colleagues.
Break down proper technique, quickly correct errors and get students to repeat until it's second nature.
What's something that makes a great mentor that also lets you know they are the right mentor for you?
When teachers believe their students are smarter than average, more adept, the students perform better.
…Rosenthal and Lenore Jacobson (1968) did the same study in a classroom, telling elementary school teachers that they had certain students in their class who were "academic spurters." In fact, these students were selected at random. Absolutely nothing else was done by the researchers to single out these children. Yet by the end of the school year, 30 percent of the the children arbitrarily named as spurters had gained an average of 22 IQ points, and almost all had gained at least 10 IQ points. The "spurters" were also rated much higher in their classroom performance by their teachers. Rosenthal compared his results to an expensive "total push" campaign funded by the Title I education act that led, after three years, to gains that were much smaller than even the gains for the control students in these classrooms. Something had definitely happened to the teachers of these students.
So the mentor that believes in you is the better mentor.


text:
Q: How can I get an update notification (e.g. via email) when a Firefox theme is updated? I love Chrome's style but I like to develop web pages using Firebug.
I'm looking at a Firefox theme named Chromifox Extreme but it says that it's not available for Firefox 8.0.
I want to be updated as soon as it is available via email. How can I get that?

A: You can ask the add-on developer to update you when a new version is available. No doubt he's getting tons of such requests, but I assume you can increase your chances of receiving an answer by contributing the $2.99 he asks for on the add-on page.
Alternatively, you can use a service like ChangeDetect to alert you to changes on the web page, assuming a new version will be announced.

A: You can create a Google Alert with query "chromifox extreme" "firefox 8". It will automatically send a mail to you when there are new Google results for such query.

redpajama_set_name: RedPajamaStackExchange


Calvin left us today. It was painless and peaceful. He was gently put down in our home, where he's lived since he was less than a year old. He was still young and had an aggressive and incurable oral cancer. Rambunctious, fearless, curious and passionate, this cat embodied the spirit of the boy Watterson illustrated in his comics.
Me and Calvin spent hours together. Everyday for four years, I'd go to work in my living room with him by my side. He was there when I got my first client. He sat with me through my hardest jobs and my most favorite jobs. When I was up at 4am, finishing a deadline, I could count on Calvin to be there through the night shift. I'd always have him to bring me joy.
Working as an freelancer can be a lonely gig. It seems a lot of illustrators, designers and artists have cats and/or other animal companions. They keep things lighthearted and fun. They're not serious. They don't give a damn about your creative block or whatever it is your working on. They bring you back down to reality and remind you to play.
Today was hard. I've lost my loyal studio mate, one of my biggest inspirations and my dearest companion. Goodbye my lovely friend and thank you. You were always there to make us laugh. You were there for our worst and our best. I'll never forget you and you'll always be my big tiger kitty, my "Calvin Man".


text:
International Challenge of Champions/
Challenge of Champions 2008/
International Challenge Of Champions – Winner-Take-All For $50,000 August 13-14, 2008
Niels Feijen will attempt to defend his crown
Billiards champions from around the world will go head-to-head in the Eighteenth Annual INTERNATIONAL CHALLENGE OF CHAMPIONS. The winner-take-all $50,000 event will be held August 13-14 at the Mohegan Sun Casino, Uncasville, CT.
The Challenge of Champions is widely considered the toughest tournament to win in professional billiards. Once each year eight international champions are brought together in a sudden-death shootout with a pressure-cooker format of winner-take-all for $50,000. The purse is one of the highest paydays in the world, and the winner claims one of the most coveted titles in pool – Champion of Champions.
The 2008 field includes top stars in the sport. Niels Feijen, 2007 winner of the INTERNATIONAL CHALLENGE OF CHAMPIONS, will defend his crown. Daryl Peach 2008 WPA World 9-Ball Champion, will represent England. Shane Van Boening, 2007 U.S. Open 9-Ball Champion, will represent America. Jain Bo Fu, the 2007 World Cup of Pool Champion, will represent China.
Dennis Orcollo, winner of the 2007 EnjoyPool.com Championship, will represent the Philippines. Jung Lin Chang, the 2008 Asia Tour Champion, will represent Chinese Taipei. Satoshi Kawabata, 2007 All Japan Open Champion, will represent Japan. Seung Woo Ryu, 2008 Grand Prix Champion, will represent Korea.
Mohegan Sun Casino, the host site, will make the 2008 event ADMISSION FREE to pool fans from around the USA and the world. The event drew such large crowds last year at Mohegan Sun that it was standing-room-only attendance. There will be four playing sessions in the two-day international tournament. On Wednesday, August 13, the quarterfinal rounds will be played at 3 PM and 6 PM, with two matches in each session. On Thursday, August 14, the two semifinals will be played at 3 PM and the final Championship match will be played at 6 PM. The semifinals and the final match will be taped for airing on ESPN in September.
The INTERNATIONAL CHALLENGE OF CHAMPIONS is regarded as the supreme test of skill in professional billiards. The eight players are so evenly matched that any one player could beat the other seven on a given day. In addition, the tournament format is the most demanding test of 9-Ball skill in the sport. The matches are two sets, race to five games each set, with a 1-game sudden death tie-breaker in the event of tied sets. The 9-ball does not count on the break, and to win a game, the 9-ball is call shot. The caliber of competition is so intense that a single mistake invariably eliminates a player from any chance at the winner-take-all purse of $50,000.
On the final night, one of the players will claim the Champion of Champions crown and a check for $50,000. The trophy and the check will be presented by Mohegan Sun. The tournament is also sponsored by PoolDawg.com, Aramith Pro Billiards Balls, Simonis Cloth, L.E.A.N.I. Slate, AcCue Shot Training Device, Executive Billiards.com, and Silver Cup Chalk.
The 2008 tournament will be the Eighteenth Annual event, and has been produced by Billiards International, Ltd. for ESPN in each of the last eighteen years. Those attending should arrive early for each tournament session and must be 21 years of age or more. Make plans today to attend the 2008 INTERNATIONAL CHALLENGE OF CHAMPIONS. For information call the Mohegan Sun toll free at 1-888-226-7711, Ext. 7163.
International Challenge Of Champions Winner-Take-All For $50,000 August 9-10
Press Release | Aug 1, 2006
Mohegan Sun Hosts Tournament of Champions Oct 29th
Press Release | Sep 20, 2008
Jian-Bo Fu of China Wins 2008 Challenge of Champions
Press Release | Aug 15, 2008

redpajama_set_name: RedPajamaCommonCrawl


Brian von Ahsen is a singer/songwriter based in Honolulu, Hawai'i on the island of Oahu where he's lived and worked since 2001. He was most often seen in performance fronting his band Social Smokers at Kainoa's Pancake House and Sports Bar in Haleiwa ("Where the North Shore Drinks").
Despite his folk and rock major influences, Brian's introduction to music was as a classically trained singer, studying voice at The University of Iowa. At age 17 he sang baritone in the Universal Academy for Music's Bicentennial National Choir in 1976 which toured Europe and performed at such venues as Carnegie Hall, Independence Hall, Royal Albert Hall and Notre Dame Cathedral. Everything changed when he picked up an acoustic guitar in 1980 and started learning Bob Dylan songs and his voice teacher told him he could not do both folk music and opera… so Brian chose folk.
Over the years Brian has performed in a wide variety of situations… from singing for an 80's top 40 cover band called Stryker in bars and at school dances all over the Midwest, to playing his solo act at open mics, bars and even once he played a two and a half hour afternoon set in front of a 5,000-strong festival crowd in rural Wisconsin.
Before coming to Hawai'i, Brian lived in Osaka, Japan for six years and during that time played in clubs regularly. It was in Osaka where Brian first formed his own band and began writing songs more prolifically. By the time he left, he and his band had received notoriety, appearing on radio programs and large music festivals.
Brian plays a large selection of classic folk rock and other music by noted musicians such as Billy Joel, Bob Dylan, James Taylor, Loudon Wainwright III, Neil Young, and Tom Waits along with a selection of his original material, best described as contemporary alternative joke-folk. He also has a great set of love ballads as well as catchy songs in French, Chinese and Japanese!
Brian's debut album The Brian Show features some of Hawai'i's finest local musicians including Alika Lyman (Alika Lyman Group), Charley Myers (Hamajang), Elijah Oguma (Sing The Body), Ginai Hill, Ian Chames (The Chames Gang), Leslie Klein (Saloon Pilots), Pierre Grill, Reggie Padilla, Stephen Inglis and Steven Howells (The Space Kadets). For more information and track previews, view the album page.


Probationary periods are not always successful despite employees' best efforts at trying. At times, the company does not see an employee fit for a company after having gauged his progress and suitability for a position. A termination letter is written in a situation such as this to provide the employee with formal notice of the end of his employment.
Termination letters while hard to write (especially if the employer has a sentimental streak in his personality) are essential to writing nonetheless. If a new employee does not work for the company, it is vital to let him go lest invite trouble with customers. A termination letter is a short and formal document that details the company's decision to allow an employee to go after the initial probationary period. It states information on why an employer believes that the employee is not suitable for the position he was hired at initially. Many companies do not bother providing a reason though – contracts usually have clauses such as 'terminate employment during probationary period without providing a reason' which makes it a bit awkward for the writer and the recipient.
But it is alright to write a reason for termination in a termination letter so that the employee is informed of why this decision was taken. Here is a sample termination letter written by an employer to an employee during his probationary period.
Heartland Alliance has determined that it is in the best interest of the marketing department to terminate your probationary employment. We have taken this action in accordance to Policy # 7 in your pre-employment contract which has been duly signed by you.
One of our major concerns while taking this decision was that you have had much difficulty in taking instructions from your supervisor over the course of the two and a half months that you have worked for Heartland Alliance. Despite many warnings from your supervisor's end, you have not altered this behavior which reflects directly on our customers who are the basis of the company's existence.
During your interview for the position of a marketing officer at Heartland Alliance, you assured us that you have no history of insubordination which was one of the main reasons you were hired. However, you have not lived up to this and we now have no choice but to end your employment with the company.
Please understand that this termination is effective immediately. You will be escorted out by one of the members of the human resource department at the end of the day after you have handed over all company property and information that you possess and taken your belongings.


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Games Are Enjoyable! You Need To Discover To Play Them.
January 9, 2023 December 15, 2022 admin 0 Comments
Whether you're a fan of games or just finding out to play them, it's constantly valuable to understand what a game is. A game is an online things that has a collection of regulations, auto mechanics, and also attributes. These are created to provide players a sense of immersion and also realistic look.
In most cases, a game can be played solo or with other people. There are a selection of categories and sub-genres, and also the listing of games remains to expand.
Most of the times, a game will have a specific objective. A few of these objectives include winning or losing, acquiring points, and also reaching a certain time limit. The video game likewise has a player-chosen problem establishing, which establishes the degree of challenge the player deals with.
Furthermore, a video game can have numerous goals, such as winning or shedding, achieving a set amount of money, or finishing a certain objective. A game can additionally have a checkpoint system, which functions as a safe point for the player. When the player lacks lives or is unable to reach a set objective, the game finishes. Some video games may also have a "champion" and a "loser." This is necessary to comprehend when making a decision which kind of video game to play.
A game's icon (GUI) is the set of buttons and various other controls that the gamer engages with while playing. This consists of the keyboard and mouse, in addition to screen-based controllers. The current video games feature outstanding levels of information, which produce an immersive experience.
Another term made use of to define the standard components of a video game is the "mesh." This is a computer-programmed collection of lines and also shapes. These can be linked to form bigger graphical aspects. A game design is produced by integrating the mesh with textures as well as other functions. This process is referred to as prototyping. A beta variation of a video game, on the other hand, is launched to the public for insect testing as well as essential responses. It typically contains all significant attributes as well as properties.
The game's version additionally has a hitbox, or collision specification, which is the area in which the character can be hit. This criterion is necessary in protecting against the personality from colliding with various other things in the video game.
A video game's mesh is additionally used to specify the size and shape of the room the personalities move in. This is particularly vital in multiplayer games, which need the room of all the players to be the exact same. This is due to the fact that a basic act of standing on the floor needs collision specifications on both the feet and also the floor.
Throughout the video game growth procedure, game manufacturers attach graphical nodes as well as make use of aesthetic scripting to arrange code visually. They can also utilize ray tracing to simulate the interaction of light with items in the game.
Some video games have a "lightmap," which is a collection of pre-rendered illumination impacts. These are additionally made use of to create deepness in the game. This is completed by catching several structures of action, also referred to as keyframing.
Normally talking, a video game is an interactive home entertainment that involves a range of factors. These elements include: the guidelines, content, gamer input, and also the atmosphere. Some video games are created to involve players with their creativities and creative thinking while others are purely artistic and also immersive.
There are also some standards that relate to all sorts of games. The first criterion is that a game should have some kind of challenge. This may come in the kind of a physical obstacle, a psychological barrier, or a psychological barrier. Oftentimes, satisfying the purposes of a video game needs abilities, luck, or a mix of the three.
The next criterion is that a game needs to have a player control. The majority of video games include more than one player, yet this is not always the instance. There are single-player video games that are battles versus time as well as ability, while there are multiplayer games that include numerous players, also.
The 3rd standard is that a video game's web content has a function. This can be attained in a variety of means, consisting of academic games that teach an ability, simulation video games that imitate a real-life scenario, and even games that are just for fun. Several organization games, as an example, focus on organizational habits as well as team building. These games can be computer system simulations, interactive board games, or perhaps physical games with props.
The final criterion is that a game is enjoyable. Some games are created to be fun for grownups while others are produced kids. There are even games that are played by specialists and also beginners alike. Some are for enjoyment while others are utilized as a tension reliever. The secret is to discover the game that's right for you.
Some usual instances of game-like functions include: a story, technicians, level layout, and also a variety of other features. These aspects are the heart of the game. The gamer should adhere to the guidelines, but seldom does she or he have to put in much effort to do so.
A range of video games are additionally created to stimulate feelings. This is usually done through an aspect of threat as well as shock. For instance, a bullet hell video game is a video game that utilizes physics to resemble the real world. The primary technician includes capturing targets, but it may likewise include dodging and also dying. The objective is to keep the characters risk-free. Various other examples include scary video games and also stealth games.
These games are made to elicit concern in the player. They are additionally developed to stimulate favorable sensations. They can be very addicting. A number of games are readily available on the market, such as Fortnite and PlayStation Virtual Reality. There are additionally various other free-to-play games that generate income from through ads or microtransactions. These games can be discovered on the Internet, in video stores, or with mobile applications. visit
The definition of a video game is occasionally disputed. The contemporary definition originates from the works of Johan Huizinga as well as Friedrich Georg Junger. The previous defines a video game as an affordable task, while the last defines it as an artform.
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[CAT]
R. Bofill Taller de Arquitectura
Architectural definition on site
The T1 Terminal of Barcelona airport was built between 2003 and 2008.
The project evolved during its construction, while new functional requirements were specified and the lack of definition of the project was resolved.
Façades:
The large glass façades of the public areas were defined and constructively detailed during the construction of the building.
More flexible new façades were designed for the technical areas, allowing several dispositions of windows without altering the general composition. U-glass was used for the cylindrical façades of the emergency stairs, providing them with natural light.
Indoor public areas:
The number of materials of the interior finishes were sharply constrained in the search for uniformity within the builing. Modulating rules and generic details were established to resolve differents situations encountered in the building.
Many interior elements were redesigned according to new functional requirements: check-in areas, air conditioning and lighting units, shops, restaurant areas...
The interior courtyards are also newly designed applying wood composites instead of stony materials.


The project is made possible through a $30,000 grant from the National Endowment for the Arts grant.
Professor of Fine Arts Shaun Cassidy will incorporate the project into a spring 2016 course.
ROCK HILL, SOUTH CAROLINA — All across the city of Rock Hill, from Earth Fare to the new Family Trust Credit Union building downtown, residents and visitors alike can enjoy beautiful permanent artwork created by Winthrop University students.
Another Winthrop artwork addition is on its way, thanks to a request from the city and a $30,000 grant from the National Endowment for the Arts. A newly planned traffic circle at Constitution Boulevard and Columbia Avenue will be the host site for whatever new pieces are created.
Professor of Fine Arts Shaun Cassidy will incorporate the project into a spring 2016 course, Special Topics in Public Art. In the class, students will conduct research and design ideas for the traffic circle before making a series of proposals to the city. A proposal will then be selected for fabrication. If possible, the students will have the chance of building whichever proposal next fall.
"That's one thing we have been working toward is trying to create a kind of level of density of artworks not only on the campus, but in the community," Cassidy said. He pointed to other Rock Hill-Winthrop artwork projects from the past, including the downtown sculpture park and the Family Trust building, among others.
He called the project a very valuable experience for students because it reflects the rigor of the creative process they'll encounter outside of the classroom, such as handling deadlines, crafting proposals, exhibiting professionalism and, more importantly, meeting the challenging parameters of a project.
"Students are going to have to be creative and innovative in how they respond to the challenges of the site," Cassidy said.
For more information, contact Nicole Chisari at chisarin@winthrop.edu or 803/323-2236.


On Friday, April 21, 1939, Victor Fleming completed filming the evening sewing circle sequence, during which Rhett convinces Melanie to tell him where the Southern vigilantes are meeting, Scarlett learns about the raid on Shantytown and Rhett brings home a wounded Ashley.
In that sequence Olivia de Havilland read aloud from David Copperfield. Yet in Margaret Mitchell's novel, Melanie reads from Les Miserables. Why the switch?
David Copperfield was a nod to producer David O. Selznick's father. Russian immigrant Lewis Selznick learned English by reading the Dickens's novel and encouraged his sons to read the tome, too, which David did at the age of seven.
As a producer, David O. Selznick convinced his father-in-law and boss, Louis B. Mayer, to allow him to bring the novel to the silver screen. Selznick and director George Cukor conducted a talent search in Canada and Great Britain for a child actor to play the title role and selected London-born Freddie Bartholomew for the part.
This entry was posted in Cinema, Film, Gone With the Wind, Movies and tagged David O. Selznick, George Cukor, Gone With the Wind, Olivia de Havilland, The Complete GONE WITH THE WIND Trivia Book. Bookmark the permalink.


Not quite fashion,we know, but with Easter around the corner we thought you might like to hear about Cocomaya, a charming little chocolate store in London. Not your average sweet shop this, there is a resident chocolatier Jonathan Deddis, who spends his day composing delicious new chocolate combinations. No one ever told us we could do this as a job, if we hadn't been so obsessed by clothes this could have been an interesting career choice. Smart chocolate stores are opening all over the place.
We like it because it is such a pretty shop with terrific windows and lovely displays, the chocolates are unusual and delicious. Deddis only uses organic or fare trade cocoa beans, including a rare South American single estate bean (yes we are still on chocolate, everything needs an interesting provenance nowadays, not enough just to be chocolate any more) and the Mangari bean from Madagascar. Whatever, they taste good but they are not cheap, from £12 to £140 for a box, but the packaging is gorgeous, so good for special presents.


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Share this Story: Crestmont West to celebrate opening of new park
Crestmont West to celebrate opening of new park
Josh Skapin
Jun 29, 2019 • June 29, 2019 • 2 minute read • Join the conversation
The new park in Crestmont West offers a playground, pergola and picnic tables. Photo by Supplied by Qualico Communities
Due to the weather, Qualico Communities has moved its Crestmont West Ice Pops in the Park event to Thursday, July 18, from 5 p.m to 8 p.m.
The event will include family-friendly summer games in the park, Ice Pops from Family Freezed, and the chance to win one of six $150 gift cards.
Crestmont West to celebrate opening of new park Back to video
"This park has it all," says Clark Piechotta, Qualico's associate director of development.
Located along Crestbrook Drive and Crestbrook Way, the park boasts a substantial play structure, basketball courts and bike racks, along with a pergola with seating. It has 152 trees, five picnic tables, seven benches and connects with 6.4 kilometres of pathways that meander through Crestmont West.
"Residents can have a picnic under the shaded pergola, there is plenty of space to kick a ball around, and kids love the modern and interesting playground," adds Piechotta.
There are more than 19 parks and green spaces in the greater Crestmont community, along with a large community hall and spray park.
Residential options in Crestmont West include single-family homes with a front-attached garage from the $580,000s, duplexes from the $500,000s, bungalow villas from the $450,000s and townhomes from the $330,000s.
Its builder group is comprised of Homes by Avi, Trico Homes, NuVista Homes, Sterling Homes, Broadview Homes and Partners Development Group.
The community, accessed from the Trans-Canada Highway, just west of Canada Olympic Park, and about 20 minutes from Calgary's downtown core, released its final lots for front-drive single-family homes earlier this year.
"Crestmont West has been a hugely popular community, and it opened up a new price point in the southwest of Calgary," says Cheryl Heilman, Qualico's marketing director. "All the lots have now been released, and there a few lots that back on the park, and some that back on the ravine.
"There are some beautiful lots left to build on," she adds.
Show homes are located on Crestbrook Way, Crestbridge Bay and Crestmont Boulevard. They're open 2 p.m. to 8 p.m. Monday through Thursday, and noon to 5 p.m. on weekends and holidays.


Many different surgical VATS procedures are performed. In our thoracoscopic VATS, four ports are used with thoracoscopic vision alone. In our hybrid VATS, two 2-cm ports are combined with muscle-sparing mini-thoracotomy with a slightly opened metal retractor with direct vision and thoracoscopic vision. Both procedures are performed by an operator, one assistant, and a scopist. Forceps, electrocautery, and ultrasonic scissors were used. VATS segmentectomy is an ideal surgical procedure to treat primary lung cancer from the perspective of minimally invasive surgery. The most important issue in segmentectomy is to maintain a sufficient surgical margin from the tumor. We think that it is important to determine whether thoracoscopic VATS segmentectomy without direct visualization or rib spreading can achieve an adequate surgical tumor-free margin. Delicate surgery is required to keep the surgical margin in segmentectomy. Therefore, the hybrid approach seems to be reasonable for obtaining sufficient surgical margins.


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Messagepoint to Present How AI is Reshaping Customer Communications at 2019 Xploration Tour Toronto
Toronto – Messagepoint Inc., a leader in the Customer Communications Management (CCM) software market, announced it will present at the 2019 Xploration Tour Toronto on how artificial intelligence (AI) is helping organizations to better communicate with their customers. The event, organized by Xplor International, runs from 9:30 a.m. to 4:20 p.m. July 17 at the City of Toronto Archives. Xplor International is a non-profit association that serves the customer communications industry. Messagepoint is a sponsor of the event, which will feature presentations on the latest trends and best practices in CCM.
Atif Khan, vice president, AI & data science for Messagepoint, will present, "How AI Will Play an Essential Role in Your Customer Communications," starting at 1:05 p.m. Khan will explore how AI is bringing order to the content chaos found in many large organizations and enabling new, innovative ways of intelligently managing, curating and optimizing content across omni-channel communications.
"We are excited to be participating in the Xploration Tour and presenting the future of customer communications," Khan said. "Content Intelligence, which is the application of AI and machine learning to content operations, is having a profound impact on how organizations create and manage their customer communications. Ultimately these technologies can dramatically increase operational efficiency and the consistency, compliance and personalization of communications across all channels to heighten the customer experience."
Messagepoint is used by financial services, insurance, and healthcare organizations to enhance customer experiences with optimized customer-facing communications across print and digital channels. Messagepoint recently announced the Messagepoint Advanced Rationalization and Content Intelligence Engine (MARCIE), an artificial intelligence and machine learning-powered capability within its award-winning CCM platform. MARCIE provides Content Intelligence capabilities across the platform for migrating legacy content into the platform, cleaning up existing content libraries, and to continuously optimize content through new assisted authoring capabilities.