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1835 aquatint showing the first production of I puritani. Note range of tones.
Aquatint is an intaglio printmaking technique, a variant of etching that only produces areas of tone rather than lines. For this reason it has mostly been used in conjunction with etching, to give outlines.[1] It has also been used historically to print in colour, both by printing with multiple plates in different colours, and by making monochrome prints that were then hand-coloured with watercolour.
It has been in regular use since the later 18th century, and was most widely used between about 1770 and 1830, when it was used both for artistic prints and decorative ones. After about 1830 it lost ground to lithography and other techniques.[2] There have been periodic revivals among artists since then.[3] An aquatint plate wears out relatively quickly, and is less easily reworked than other intaglio plates. Many of Goya's plates were reprinted too often posthumously, giving very poor impressions.[4]
Among the most famous prints using the aquatint technique are the major series by Goya, many of The Birds of America by John James Audubon (with the colour added by hand), and prints by Mary Cassatt printed in colour using several plates.
TechniqueEdit
Goya, No. 32 of Los Caprichos (1799, Por que fue sensible). This is a fairly rare example of a print entirely in aquatint.[5]
In intaglio printmaking techniques such as engraving and etching, the artist makes marks into the surface of the plate (in the case of aquatint, a copper or zinc plate) that are capable of holding ink. The plate is inked all over then wiped clean to leave ink only in the marks. The plate is passed through a printing press together with a sheet of paper, and strong pressure applied pushing the paper into the marks, so that a transfer of the ink to the paper occurs. This is repeated many times. Like etching, aquatint uses the application of a mordant (acid) to etch into the metal plate. Where etching uses a needle to scratch through an acid-proof resist and make lines, aquatint uses powdered rosin (resin) to create a tonal effect. The rosin is acid resistant and typically adhered to the plate by controlled heating; where the grains are will print white, with black areas around. The tonal variation is controlled by the level of mordant exposure over large areas, and thus the image is shaped by large sections at a time. The rosin is then washed off the plate before printing.[6]
Another tonal technique, mezzotint, begins with a plate surface that is evenly indented and roughened so that it will print as an even and fairly dark tone of ink. The mezzotint plate is then smoothed and polished to make areas carry less ink and thus print a lighter shade. Alternatively, beginning with a smooth plate, areas are roughened to make them darker. Occasionally the two techniques of aquatint and mezzotint are combined.
Philibert-Louis Debucourt, The Public Promenade, 1792. Printed in colour from various plates, using etching, engraving, and aquatint. One of the leading achievements of the French 18th-century colour-print.
To 1830Edit
A variety of early experiments aimed to add tonal effects to etching included the first use of a resin dust ground by the painter and printmaker Jan van de Velde IV in Amsterdam, around 1650. However none of these developed a technique that caught on with other printmakers.[7] Experimentation by several artists with somewhat different techniques reached a peak after about 1750, and as they were initially very secretive, the history of the emergence of the standard technique remains unclear.[8]
Various claimants include the Swede Per Floding working with the Frenchman François-Philippe Charpentier in 1761, J. B. Delafosse in 1766, working with the amateur Jean-Claude Richard (often rather misleadingly known as the Abbé de Saint-Non) in 1766, and Jean-Baptiste Le Prince in 1768-69. Le Prince was more effective than the others in publicizing his technique, publishing Découverte du procédé de graver au lavis in 1780, though he failed to sell his secret in his lifetime. It was bought posthumously by the Académie royale de peinture et de sculpture in 1782, who released it on an open basis.[9]
Joseph Lycett, The residence of Edward Riley Esquire, Wooloomooloo, Near Sydney N. S. W., 1825, hand-coloured aquatint and etching printed in dark blue ink. Australian print in the tradition of British decorative production. The artist had been transported for forging bank notes.
Though England was to become one of the countries using the technique most, the earliest English aquatints were not exhibited until 1772, by the cartographer Peter Perez Burdett. It was taken up by the watercolourist Paul Sandby, who also seems to have introduced technical refinements as well as inventing the name "aquatint".[10] In England artists such as Sandby and Thomas Gainsborough were attracted by the suitability of etched outlines with aquatint for reproducing the popular English landscape watercolours, which at this period usually also had been given an initial outline drawing in ink. Publishers of prints and illustrations for expensive books, both important British markets at the time, also adopted the technique. In all these areas, a print with etching and aquatint gave very satisfactory results when watercolour was added by relatively low-skilled painters copying a model, with a flat wash of colour on top of the varied tones of the aquatint.[11] After the French Revolution, one of the most successful publishers in London, the German Rudolf Ackermann, had numbers of French refugees working on the floor above his shop in The Strand in London, each brushing a single colour and then passing the sheet down a long table.[12]
Over the same period in France there was sustained interest in techniques for true colour printing using multiple plates, which used multiple printmaking techniques which often included aquatint (or mezzotint) for tone. Artists included Jean-François Janinet and Philibert-Louis Debucourt, whose La Promenade Publique is often thought the masterpiece of the style.[13] Another branch of this French movement mostly used mezzotint for tone and came to specialize in illustrating medical textbooks. This was at first led by Jacob Christoph Le Blon (1667–1741), who very nearly anticipated modern CMYK colour separation and then carried on by his pupil Jacques Fabien Gautier d'Agoty and later members of the d'Agoty family until around 1800.[14]
Goya, maker of incontestably the greatest prints using aquatint, probably learned of the technique though Giovanni David from Genoa, the first significant Italian to use it. Goya used it, normally with etching and often burnishing and other techniques, in his great print series Los Caprichos (1799), Los Desastres de la Guerra (1810–19), La Tauromaquia (1816) and Los disparates (ca. 1816–23).[15]
RevivalEdit
Mary Cassatt, Woman Bathing, drypoint and aquatint, from three plates, 1890-91
After a period of several decades in the central 19th century when the technique was little used, and definitively superseded for commercial uses,[16] it was revived near the end of the century in France, by Édouard Manet, Félicien Rops, Degas, Pissarro, Jacques Villon and other artists.[17] In 1891, Mary Cassatt, based in Paris, exhibited a series of highly original coloured drypoint and aquatint prints, including Woman Bathing and The Coiffure, inspired by an exhibition of Japanese woodblock prints shown there the year before. These used multiple blocks for the different colours. Cassatt was attracted to the simplicity and clarity of Japanese design, and the skillful use of blocks of colour. In her interpretation, she used primarily light, delicate pastel colours and avoided black (a "forbidden" colour among the Impressionists).
It continued to be used in the 20th century, with the Czech T. F. Šimon and the German Johnny Friedlaender notably frequent users. In the United States the printmaker Pedro Joseph de Lemos popularized aquatints in art schools with his publications (1919–40), which simplified the cumbersome techniques, and with traveling exhibitions of his award-winning prints.[18]
Modern processEdit
Demonstration sections of printed aquatint, magnified.
aquatint box, used to apply resin powder on the plate.
An aquatint requires a metal plate, an acid, and something to resist the acid. Traditionally copper or zinc plates were used. The artist applies a ground that will resist acid. Ground is applied by either dissolving powdered resin in spirits, applying the powder directly to the surface of the plate, or by using a liquid acrylic resist. In all forms of etching the acid resist is commonly referred to as "the ground."
An aquatint box is used to apply resin powder. The powder is at the bottom of the box, a crank or a bellows is used to blow the powder up into the air of the box. A window allows the engraver to see the density of flowing powder and to place his plate in the box using a drawer. When the powder covers the plate, it can be extracted from the box for the next operations.
The plate is then heated; if the plate is covered with powder, the resin melts forming a fine and even coat; if it is in spirits, the spirits evaporate and the result is essentially the same. Now the plate is dipped in acid, producing an even and fine level of corrosion (the "bite") sufficient to hold ink. At this point, the plate is said to carry about a 50% halftone. This means that, were the plate printed with no further biting, the paper would display a gray color more or less directly in between white (no ink) and black (full ink).
Zinc plate with powder resin.
At some point the artist will then etch an outline of any aspects of the drawing they wish to establish with line; this provides the basis and guide for the later tone work. They may also have applied (at the very start, before any biting occurs) an acid-resistant "stop out" (also called an asphaltum or hard ground) if they intend to keep any areas totally white and free of ink, such as highlights.
The artist then begins immersing the plate in the acid bath, progressively stopping out (protecting from acid) any areas that have achieved the designed tonality. These tones, combined with the limited line elements, give aquatints a distinctive, watery look. Also, aquatints, like mezzotints, provide ease in creating large areas of tone without laborious cross-hatching; but aquatint plates, it is noted, are generally more durable than mezzotint plates.
The first etch should be for a short period (30 seconds to 1 minute, with a wide variation depending on how light the lightest tones are meant to be). A test piece may be made with etching times noted, as the strength of the etchant will vary. More than thirty minutes should produce a very dark area. Etching for many hours (up to 24) will be as dark as etching for one hour, but the deep etch would produce raised ink on the paper.
Contemporary printmakers often use spraypaint instead of a powder, particularly when using the technique known as sugar-lift. To produce a printing surface using sugar-lift, the artist makes a solution of India ink and sugar by melting sugar into heated ink. This mixture is then applied to a prepared plate with a brush, allowing for a bold expression not possible with the most etching techniques. When the ink/sugar mixture is dry the plate is coated with asphaltum (liquid ground); the plate is then submerged in warm water which dissolves the sugar so that the image "lifts off" the plate. The exposed areas are then aquatinted to hold ink and the plate is ready to be printed from.
Paul Sandby, The Iron Forge between Dolgelli and Barmouth in Merioneth Shire, Plate 6 of XII Views in North Wales, 1776, etching and aquatint printed in brown.
Paul Sandby, View near Edwinsford, Carnarvonshire, 1812, with colours added by hand.
Goya, # 20 from the Tauromaquia series (1816), The agility and audacity of Juanito Apiñani in the ring at Madrid, etching and aquatint
Eugène Delacroix, Turk Mounting His Horse, 1824, aquatint only.
Edgar Degas, Dancers in the Wings (Danseuses dans la coulisse), c. 1877, etching, aquatint, and drypoint
Félicien Rops, Little Sorceress, 1879, etching and aquatint
Comedy of Society, Jacques Villon
Allan Osterlind, Flamenco Dancers
Émile Dezaunay
T. F. Šimon, Second Hand Booksellers, Spring (in Paris), 1912, colour soft ground etching and aquatint
John Taylor Arms, On Lake Como, Number Two, 1919, colour printed etching and aquatint
Famous examplesEdit
Francisco Goya famously took great advantage of aquatint printmaking, in his Los Caprichos series (1799); Los Desastres de la Guerra (1810–19); La Tauromaquia (1816); and Los disparates (ca. 1816–23).
Master engraver Robert Havell used aquatint for John James Audubon's Birds of America (1826–38).
David Hockney, known for his many paintings of the Los Angeles lifestyle in the 60's, has created a number of aquatints and etchings used with color in his "The Blue Guitar"[19] series of prints.
La Belle Assemblée, a British women's magazine published from 1806 to 1837 had many aquatint colored plates.
^ Griffiths, 89-90
^ Mayor, 612-614
^ Gascoigne, 17d; Griffiths, 94-96
^ Griffiths, 150-151
^ Griffiths, 150
^ Griffiths, 92; Hind, AM (1963) A History of Engraving and Etching. Dover Publications, New York.
^ Griffiths, 94; Ives (MMA)
^ Griffiths, 94; Ives; Ann V. Gunn, "Sandby, Greville and Burdett, and the 'Secret' of Aquatint," Print Quarterly, XXIX, no. 2, 2012, pp. 178-180.
^ Griffiths, 94
^ Ives (MMA); Griffiths, 94
^ Edwards, Robert W. (2015). Pedro de Lemos, Lasting Impressions: Works on Paper. Worcester, Mass.: Davis Publications Inc. pp. 67, 91 notes 355–357. ISBN 9781615284054.
^ "David Hockney : Graphics / Blue Guitar". Hockneypictures.com. Retrieved 12 February 2012.
Gascoigne, Bamber. How to Identify Prints: A Complete Guide to Manual and Mechanical Processes from Woodcut to Inkjet, 1986 (2nd Edition, 2004), Thames & Hudson, ISBN 050023454X, (sections instead of numbered pages)
Griffiths, Antony, Prints and Printmaking, 1996, British Museum Press (in UK), 2nd edn ISBN 071412608X
Ives, Colta Felle (1974), The Great Wave: The Influence of Japanese Woodcuts on French Prints, 1974, The Metropolitan Museum of Art, ISBN 0-87099-098-5
Ives, Colta (MMA). "The Printed Image in the West: Aquatint". In Heilbrunn Timeline of Art History. New York: The Metropolitan Museum of Art, 2000–. accessed January 2019
Mayor, Hyatt A., Prints and People, Metropolitan Museum of Art/Princeton, 1971, fully available online as PDF,ISBN 0691003262
"Aquatint (printmaking) – Britannica Online Encyclopedia". britannica.com. Retrieved 17 October 2009.
"Aquatint (printmaking) – Hans Koernig Painter and Printmaker". hans-koernig.de. Archived from the original on 19 July 2011. Retrieved 3 November 2009.
Wikimedia Commons has media related to Aquatint prints.
Prideaux, S. T. Aquatint engraving; a chapter in the history of book illustration (London : Duckworth & Co., 1909).
Retrieved from "https://en.wikipedia.org/w/index.php?title=Aquatint&oldid=902502556"


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Art Applewhite Roc ... (36 of 105)
5-Star ReviewsArt Applewhite Rockets ReviewsKit ReviewsReviews by Lance AlligoodReviews of Hourglass 24mm (Long)
Art Applewhite Rockets - Hourglass 24mm (Long)
Contributed by Lance Alligood
Overall Rating: starstarstarstarstar
Manufacturer: Art Applewhite Rockets
The 24mm Long Hourglass is a spool-like rocket that uses many visual cues and construction techniques from Art Applewhite's other designs. As with all of Art's kits, the Long Hourglass relies on a high drag design to limit altitude and create a tumbling, aerobrake recovery for a safe, close return. And did I mention, SPOOLS RULE!
The build is like building one of Art's Delta Saucers inside-out. There are only four parts that make up the Hourglass: cardstock for the cones, top, and bottom, foamboard for the top and bottom discs, 3.75" long 24mm motor tube, and 3.75" motorhook. Even though it won't take more than an hour of your time to build, don't underestimate this kit. It is a challenging build, especially if you've never built one of Art's kits before.
You start with cutting out and gluing the 2 paper shrouds to form them into cones. Next, the remaining cardstock is glued onto the foamboard and let dry. You want to make sure that there is enough glue to cover the cardstock yet not so much that it causes the cardstock to swell or wrinkle. Then, with a sharp new #11 X-Acto blade (or I prefer a razor utility knife), carefully cut out the 2 discs that will make up the top and bottom along with the center holes for the motor mount tube and launch rod/motor clip holes. 220/250/320 grit sandpaper may be needed to help smooth out any rough edges or assist with parts fitting together. The motor mount tube has a 1/8" slot cut 1/4" from one end of the tube. The motor hook is inserted into the tube & held in place with a couple wraps of clear cellophane tape around the middle of the tube.
The top disc (the one without the motor hook hole) is glued and filleted onto the motor tube at the end where the motor hook extends into the tube. Returning to the shrouds, one is slid onto the tube so that the large, open end faces the top disc. The second shroud slides on the opposite way. Hold off on gluing the shrouds until after the bottom disc is attached. The shrouds on my kit more than made for a snug fit, requiring some minor trimming of the smaller end and launch rod holes for a proper fit. In communicating with Art during the build, he assured me that this was an early production mistake and has already been fixed in current kits. With the top disc and both shrouds in place, a small ring of white glue is smeared ont eh aft end of the tube and the bottom disc is fitted into place so that it lines up with the launch rod and motor hook holes until ~1/16" of the motor tube is exposed out the aft end. That small bit of tubing then receives a fillet of white glue for support.
Once the discs are dry, the shrouds need to be attached to the discs. Making sure that the launch rod holes are all lined up, the shrouds are filleted to the discs and around the center of the rocket to each other.
Typical of Art's products, no painting is required, which I know is a big plus for some rocketeers out there...although that means that you have to make a color selection at the time of placing your order. Art does suggest that you clear coat the entire model to help protect it from the elements. Before clear coating (or painting) though, white glue needs to be smeared along the exposed edges of the foamboard, as the chemicals in the paint will dissolve the foam! And even if you choose not to paint the Hourglass, it's still a good idea to seal the foam. I've built several of Art's products and have not clear coated any of them but I still took the time to seal the foam edges. If I had one complaint (and it's very minor, really!) about the Long Hourglass, it's that not all of the surfaces are colored to match. (Although in retrospect, I certainly could have used the leftover cardstock to accomplish this--without having to resort to paint it!)
The Long Hourglass is designed for 3.75" 24mm motors like the Estes E9 and Ellis Mountain E10-6. No spacer is included for shorter (2.75") motors, but to ensure the rocket's stability, I think Art (and I) would suggest that you build/fly/use the (standard) 24mm Hourglass rocket if you want to use those shorter motors.
I have learned from building and flying many spools, that spools (and all high drag rockets) perform best when combined with low thrust, long burn motors. With their light mass (less than 1oz for the Long Hourglass), they don't need much to get off the launch pad but they need a steady source of thrust to keep them up in the air. The end of the thrust phase and apogee occur pretty much simultaneously. Unlike the graceful, direct downward glide of Art's saucers and Qubits though, spools almost always go into a rapid end-over-end spinning tumble.
Although it isn't on the recommended motor list, I decided to be a brave soul and fly my Long Hourglass for the first time on an AeroTech SU F21-4W with the ejection charge removed. With the Copperhead ignitor readied with some masking tape, the Long Hourglass was set on one of the mid power pads. It pleasantly ignited on the first try and zipped off the pad to well over 300 feet.
Not only is there no recovery system to prep, but there's nothing that can fail either! Even on windy days, you can expect to have short walks to recover the Long Hourglass.
At the very end of the thrust phase, the rocket went into a rapid spin, which really surprised almost everyone watching. There was no danger of it coming back with any problems though as it then tumbled slowly back to the ground end over end and landed impressively close to the pad. Unfortunately, we launch off of an asphalt surface so one of the discs and shrouds bent slightly from the impact. The damage was minimal enough so that it can safely fly again...and on another F21 at that!
With the bright neon colors and paper shrouds, there's no doubt that this is a true Art Applewhite design. Unlike some of the spool rockets I have previously scratchbuilt, the Art Applewhite Long Hourglass is designed to last.
For a bit more on the 24mm Long version of the Hour Glass, check out Dick Stafford's review here

redpajama_set_name: RedPajamaCommonCrawl


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Oxford Essential French Dictionary (English and French Edition)
french,english
The oxford essential french dictionary is a new compact french-english and english-french dictionary that offers up-to-date coverage of all the essential day-to-day vocabulary with over 40,000 words and phrases and 60,000 translations. This dictionary is easy to use and ideal for travel, work, or study. The latest words in each language have been added, reflecting all aspects of life today, from computing and technology to lifestyle and business. Additional features include guides to french and english pronunciation, as well as help with both french and english verbs. The oxford essential french dictionary is ideal for anyone in need of a handy quick reference. An essential book for the study of french. Explore our language resources on oxforddictionaries. Com, oxford's home for dictionaries and language reference. Updated regularly with the latest changes to words and meanings, the site provides hundreds of thousands of definitions, synonyms, and pronunciations in a range of languages. Access the highest quality language content, built from our extensive research, for free on your desktop or device.
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Originally released as a "Candy Toy" in Japan, just like the other various Super Mini-Pla, the Voltron was repackaged as a full set packed in one box for the USA release, whereas the original Japan version came with each Lion packed separately in smaller boxes.
There's also a SDCC 2018 variation of this kit, it has a different box and comes with a bonus "Form Blazing Sword" effect accessory.
I'm not a fan of the connection plugs sticking out like this. But I guess it is what it is.
I love the fact that you can pose the lions in sitting position.
It's not quite perfect (needs more range of motion in the torso ab crunch).
But close enough that you can somewhat recreate the pose from the closing credits of the cartoon.
The set comes with Black Bazooka and Mouth Blade.
The Red Lion also comes with an alternate bigger head for better proportion in Voltron mode.
The Green Lion also comes with an alternate bigger head for better proportion in Voltron mode.
The set comes with Green Lion's Laser Cannon/ Green Gun (R) and Shooting Star/ Green Knife (L) and Mouth Blade.
The Blue Lion also comes with an alternate bigger head for better proportion in Voltron mode.
The kit comes with Marine Missile, Shoulder Cannon/ Ice Missile (R) , Triple Barrel Mortar Cannon (L) / and Mouth Blade.
The Yellow Lion also comes with an alternate bigger head for better proportion in Voltron mode.
The kit comes with Dual Shoulder Blockbuster Turrets/ Sand Cannon (R) , Radial Shotgun Shoulder Blaster / Gattling Missile (L) and Mouth Blade.
The legs of the lions are removable, They can be replaced with covers for show accuracy. Note that the covers are specific to each lion in terms of design.
I'm really glad that the face and chest pieces for Voltron are pre-painted and didn't require much input from me, my model kit skills are pretty pathetic. The assembled kit looks great and the figure is really highly poseable. It's quite a thrill to see it completed.
Fully assembled, Super Mini-Pla Voltron stands roughly 6.5 inches (7 inches counting the wing tips).
Voltron also roughly weighs 117 Grams.
Thanks to the many, many joints of the toy, it makes it a fun figure to pose. It's really a lot of fun.
The figure is also very well balanced, you can make it stand on one leg (but requires some work to get right).
As a bonus, you can assemble all of the weapons together to form a "secret" weapon for Voltron, although this weapon never appeared in the series, it's a nice concept.
Overall, a great toy! I love that we get a Voltron toy that's super posey in both Lions and Voltron forms and is really stable. The only downside is that it requires assembly. If this were released as a completed set, it would really be awesome! As is, I can still recommend it, but you will need to set aside time (roughly 5 hours) to build the thing (properly) first.


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Arizona bill would require warrant before Department of Child Safety removes children from homes
Mary Jo Pitzl
Arizona could make the first move toward requiring the Department of Child Safety to obtain a warrant prior to removing a child from his or her home under legislation expected to be introduced next week. It would be a major change for an agency that is often the target of angry parents who complain the state is taking their children for no good reason.
The bill would be a "half step" toward the goal of a warrant requirement for the state's child-welfare program, said Rep. John Allen, R-Scottsdale. He said he intends to introduce his proposal next week, most likely as a strike-everything amendment on a Senate bill.
Several other states require a judge's approval before taking a child.
ARIZONA'S DCS: Why are kids taken away? Too often the answer is unknown
Allen said the first step is technical: It would remove a procedural requirement so a case gets before a juvenile-court judge quickly. The intent is to have a judge determine if a child should be removed before the agency acts.
Currently, judges approve or reject a child removal after the fact, when they receive what is called a dependency petition from DCS. That takes time, since a petition requires some level of investigation, filling out a checklist and consultation with attorneys for the state. State law allows DCS three days (excluding weekends and holidays) to do that, with exceptions if a caseworker determines the child is in present danger.
Allen said the idea is to let DCS — which is regaining lawmaker trust with a recent show of progress in key areas — run a pilot program during the summer. They would analyze results, which would help shape legislation next year to create a warrant program. That should show whether the policy change would result in fewer children being removed from their homes.
"There's a lot of members who want this," Allen said.
RELATED: Soon judges, not Arizona Department of Child Safety alone, could decide when to take children from families
A number of lawmakers believe that requiring a juvenile-court judge to issue a warrant before a child is removed would reduce the number of children who are in out-of-home care and overseen by the DCS. That number was 17,149 as of December, down 9.3 percent from March 2016.
DCS, activists supportive, but urge caution
DCS Director Greg McKay said he's on board with the idea, but cautioned the agency needs to move deliberately.
He said DCS has worked intentionally to reduce caseloads and the number of kids in out-of-home care, and he doesn't want to introduce an abrupt policy change that would reverse those gains.
Besides, it will take awhile to set up a warrant system, he said. For example, the juvenile courts, which are housed in each county, would need to ensure they have a judge on call 24/7 to handle requests.
"We need unsafe kids with no options (to be) in foster care, and safe kids to remain in their own homes," he told The Arizona Republic.
MORE: Applications being accepted for Arizona child-abuse prevention grants
A warrant policy would include exceptions for "exigent" situations, McKay said, so caseworkers could work swiftly if they find a child in imminent danger.
Some activists, who have pushed for a mandatory warrant policy, say they're happy the agency is pursuing the change. But they say they're nervous about how broadly the "exigency" standard will be interpreted, fearing it could be used even in cases that they think don't pose immediate harm.
"My concern is it would be toothless," said Del McArdle, who was the legal guardian of his nephew when DCS removed him from McArdle's care.
Rep. Kelly Townsend, R-Mesa, introduced House Bill 2507 earlier this year to narrowly define "exigent," but the measure did not get a hearing.
DCS making progress
The warrant discussion came after members of the Joint Legislative Budget Committee praised McKay and his agency for strides in fixing a number of areas, including a nagging backlog of cases.
Chairman Rep. Don Shooter, R-Yuma, offered to kick in $50 for fireworks so the agency could celebrate.
REPORT: Real progress at Arizona's DCS, but 'a long way to go'
The panel, which oversees budget issues, had harshly criticized the agency for failing to fix problems.
This week, the agency reported progress in the following key areas where lawmakers said they needed to see progress. All numbers are compared to March 2016:
A 5.8 percent increase in the number of caseworkers, to 1,344. However, the agency is still short of the 1,406 caseworkers the Legislature has authorized.
A 9.3 percent reduction in the number of kids in out-of-home care (such as foster homes and group homes), to 17,149 from 18,917.
A 91 percent reduction in the backlog of cases involving abuse or neglect, to 966 from 10,751. That puts the agency below the goal of 1,000 backlogged cases and frees up $2 million for overtime pay and $765,000 to hire new case aides.
Reach the reporter at maryjo.pitzl@arizonarepublic.com and follow her on Twitter @maryjpitzl.
Arizona child-welfare agency drops policy on 'covert' use of controversial lie-detection technology


The giant amounts of radiation the Van Allen belts generate can pose serious risks for satellites.
Interesting, but is it all to be believed.
Ive heard stories of just how much radiation there is in said belts, and what would be needed to shield from it even for a few minutes.
From what I understand not a single Apollo mission had appropriate shielding. Only the shuttles had, and they didn't tend to go That far out to the radiation.
I think about that a lot, too. Makes you wonder.
Thanks a lot Nate Onyx Blogger is being very temper-mental at the momentRadiation badge.


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Category Archives: History
October 1, 2014 · 10:35 pm
Oklahoma's forgotten soldier diplomat
In 1944, Major General Patrick J. Hurley was given what proved to be an impossible task: reconciling the Nationalist Chinese of Chiang Kai-shek and the Communists of Mao Zedung.
Hurley was one of the most influential Oklahomans of the first half of the twentieth century. Born to Irish immigrant parents in the Choctaw Nation, he became a prominent Tulsa attorney and businessman and an Army officer who served with distinction in World War I. In 1929, Hurley was named Secretary of War in the Hoover administration, thus becoming the first Oklahoman to hold a cabinet-level position.
Although a partisan Republican, during World War II Hurley became Franklin Roosevelt's personal envoy to the Soviet Union and later the Far East. It was in this later capacity he arrived in China, initially to mediate the tense relationship between the autocratic Chiang and prickly U.S. General Joseph Stilwell.
Stilwell, however, had already reached the point of no return. Against Hurley's advice, he confronted Chiang with an ultimatum that resulted in Stilwell's replacement.
Although the Communists and Nationalists were nominal allies against the Japanese, their armies functioned more or less independently and sometimes at odds with each other. Hurley's task was to set the foundation for a united China during the final stages of the war and going forward.
The U.S. position was a difficult one. Its alliance of necessity with the Soviet Union aside, the United States was not keen on promoting communism. Those familiar with the situation, though, generally found the Communists better organized and disciplined and less corrupt than the Nationalists. Stilwell's staff, in fact, clandestinely equipped and assisted the Red Army, and continued to do so even after Stilwell was recalled.
Throughout his time in China, and during two trips back to Washington, Hurley contended not only with the seemingly intractable differences between the Communists and the Nationalists, but intrigue within the U.S. State Department.
John Carter Vincent, the official in charge of Washington, fought long-term commitments to Chiang, preferring "flexibility which would permit cooperation with any leadership in China …." State Department officials in China leaked confidential information to Mao, undermining Hurley's attempts to negotiate a coalition government led by Chiang.
Vincent gained considerable influence following Roosevelt's death, and in November 1945, Hurley called a press conference in Washington to announce his resignation. He told reporters that State Department personnel in China had collaborated with the Communists in an effort to oust Chiang and the Nationalists.
The furor thus created effectively ended, but he does not seem to have minded much. He moved to Santa Fe, N.M., where he became involved in uranium mining, and ran unsuccessfully for the U.S. Senate three times. He died in 1963 at the age of 80.
Hurley is now largely forgotten, but at least one important monument to him remains in Tulsa. In 1929, Hurley and a business partner built the first "apartment hotel" in the city at 1314 S. Main St. Restored in the 1990s, the Ambassador Hotel is today the city's most exclusive boutique hotel.
August 31, 2014 · 11:01 pm
Oklahoma's Ewe Lamb Rebellion
William Henry Davis "Alfalfa Bill" Murray generally wins the prize for Oklahoma's most colorful and eccentric public figure. Born in Toadsuck, Texas, he became an intermarried citizen of the Chickasaw Nation, was president of the Oklahoma constitutional convention and first speaker of the Oklahoma House of Representatives. He served in Congress, started an ill-fated agricultural cooperative in Bolivia and hitchhiked his way to victory in the 1930 gubernatorial election.
Gruff, profane, ill-kempt, Murray denounced the Ku Klux Klan, called African Americans "coons" and sent the National Guard to keep Texas from opening a toll bridge across the Red River. He tromped around the governor's office in his stockinged feet, had the executive mansion's lawn planted to potatoes and made a delusional run for the presidency in 1932.
So yeah, he was pretty far out there.
But for sheer unadulterated weirdness, Henry S. Johnston runs a close second. A Biblical scholar, he also dabbled in Rosicrucianism, an esoteric and obscure philosophy allegedly based on "ancient truths" passed from Middle Eastern mystics to a medieval German named Christian Rosenkreutz. Johnston attended seances with his wife, consulted astrologers and numerologists, claimed to have been reincarnated at least twice, and counted his secretary's canaries among his closest advisers.
In the end, it wasn't the canaries that proved his undoing. It was the secretary.
These were hazardous times for Oklahoma governors. The previous elected chief executive, Jack Walton, last just 10 months before the Legislature removed him from office. Impeachment proceedings were initiated against two more of the state's early governors, and a third had been indicted on federal fraud charges.
Johnston was elected governor in 1926. A dapper, scholarly man, he had been the first president pro tempore of the Oklahoma Senate, and for a short while it appeared his term as governor would be a successful one. At his urging, the Legislature increased appropriations for common education and authorized the construction of a crippled children's hospital.
But lawmakers used to speaking to the chief executive whenever they liked were at first annoyed and then outraged by Johnston's appointment of an executive secretary, Mayme Hammond, who blocked the door to the governor's office. More than that, they believed, she exercised undue and possibly even mystical influence over Johnston, and at times acted as the de facto governor. At the end of the 1927 legislative session they demanded Hammonds be fired.
Johnston, in his typically meandering manner, refused.
"If you came to me with a thousand sheep," he said, "and I had only one ewe lamb and you wanted me to destroy that, do you think I would be so base as to destroy it? I repeat, gentlemen, it would be yellow, it would be unjust to Mrs. Hammonds to sacrifice her and her character on false charges."
Thus began what became known as the Ewe Lamb Rebellion.
Hammonds' opponents labeled her a "She-svengali" and initiated a special session for the purpose of driving her and Johnston from office. Hammonds probably didn't help herself any by explaining her ability to keep track of goings-on all over the state through astral projection. It also didn't help that her relatives, including her husband Dr. O.O. Hammonds, began showing up and the state payroll.
The initial attempt to oust Johnston failed, but the continued presence of Hammonds and Johnston's support of the Al Smith, the Democrats' Catholic, anti-Prohibition candidate for president in 1928, eventually led to his undoing. In 1929, Johnston was convicted on a single count of incompetence and removed from office.
Thus, Oklahoma became and remains the only state to impeach and remove from office two consecutive elected governors.
Lieutenant Governor William J. Holloway, a level-head former state Senator, replaced Holloway and was able to put through several significant reforms during his short time in office. More importantly, he instilled a sense of order to state government despite the turmoil of the onset of the Great Depression.
But the Oklahoma constitution barred Holloway from seeking election to a full term in his own right, thus opening the way for Alfalfa Bill Murray — an eccentric, to be sure, but an eccentric no one dared impeach.
Filed under History, Politics
Tagged as Alfalfa Bill Murray, Henry S. Johnston, impeachment, Oklahoma
The hanging of Frank Henson
Before lethal injection, before the electric chair, before the walls went up at the state prison in McAlester, individual counties were responsible for executing criminals convicted of capital crimes.
Only one such execution occurred in Tulsa County.
In early 1911, a scuffle broke out in a bar at Dawson. Dawson has long since been absorbed into the city, but in 1911 it was a rural ranching and coal-mining community on the Frisco line. When the dust cleared, a county deputy names Charles Stamper was dead and all fingers pointed to a black man who went by the name Frank Henson.
Henson was duly trialed and sentenced to death. Remarkably, given current attitudes, Tulsa County appealed the sentence. It did not want to execute Henson or anyone else. Oklahoma had executed only two people in its first three years of statehood, and Gov. Lee Cruce opposed capital punishment on moral grounds. But in this case he refused to intervene. Frank Henson was to hang by the neck until dead.
Sheriff Bill McCullough, a former cowboy with a big handlebar mustache, had the job of building the scaffolding and, when the executioner failed to show up, tying the noose, putting it around Henson's neck, and dropping the trapdoor. McCullough would be sheriff a decade later during Tulsa's 1921 race riot, but late in life called the Henson execution "about the worst job I ever had to do."
Henson, maintaining his innocence until the end, was brought to the gallows just after dawn on March 31. Five hundred people had gathered to watch, despite the hour.
A black preacher named C.L. Netherland read the Twenty-third Psalm. Henson asked to speak. The witnesses had lied, he said. Stamper fired first, without identifying himself, said Henson.
"I'm going to get higher than any of you," he said. "Some of you are going to have tribulations getting there."
Henson prayed for McCullough and the other lawmen escorting him, asked God to forgive them, "for they know not what they do."
Then, finally, he said, "My name is not Frank Henson. It is Amos Bell. You won't find anything bad behind that name."
The noose was then placed around Henson's — or Bell's — neck and a hood placed over his head.
"Are you ready Frank?" McCullough asked. When Henson didn't respond, the sheriff added "may God bless you," as he pulled the lever to drop the trap door.
"Whether the execution of Henson was justifiable was a question debated her for some time," the Tulsa World reported. "Many wanted the sentence commuted to life imprisonment."
Even in 1911, it seems, capital punishment was a source of controversy and strong feelings.
Tagged as capital punishment, Oklahoma history, Tulsa history
Drugs wars and the Tulsa race riot
One of the things I've wondered for many years is whether drugs could have played a role in Tulsa's 1921 race riot.
Drugs, and especially opiates, were a serious problem, even in those days. At least as far back as 1907, before statehood, police raided an opium den in what was then a town of seven thousand. By 1921, morphine and cocaine addiction had become a serious problem.
In January, federal agents raided a soft drink stand adjacent to McNulty Park — the stadium which would serve briefly after the riot as a holding area for black Tulsans — operated by one Irma "The Midget" Harisson. When a search of the premises failed to turn up the expected contraband, one of the agents grabbed the four-foot, six-inch Harisson by the ankles, turned her upside down, and shook her until cocaine capsules fell from her clothes.
Over the next several months, two doctors were sent to federal prison for illegally selling morphine and cocaine; two men were arrested in Tulsa and charged with possession of one thousand grains of morphine; a double amputee working in a shoe-shine parlor was found with five morphine and three cocaine capsules; a man named J.L. Love was fined $500 and sentenced to a year in prison for morphine possession; and two men were apprehended at the train station with a valise full of "liquid morphine."
In May, police caught two drug dealers by making a buy with a marked silver dollar.
In the immediate aftermath of the May 31-June 1 Tulsa riot and for years afterward, official blame fell mostly on armed blacked men who went to the county courthouse to defend a prisoner they believed was about to be lynched. A confrontation ensued, shots were fired and riot was on.
Several of those men were described, by both whites and blacks, as dope peddlers and drug users. Today that claim is generally dismissed and in all likelihood rightfully so. But the fact it would be accepted as plausible suggests the extent of the drug problem in Tulsa at the time.
After the riot, police reported white drug dealers did indeed enjoy a windfall from the riot. One of the buildings destroyed in the fires that engulfed much of the black neighborhoods, they said, had been a well-known den, and Officer Henry Carmichael reported white dealers were "unusually active" since their black competitors had been temporarily put out of business.
Certainly, the riot was not about drugs, and I wouldn't want anyone to make too much of this. But, as I said, I have long wondered if just may the riot did provide an opportunity for underworld characters to settle scores or get rid of competition.
I guess it's just one of those things we'll never know.
Bill Tilghman
Bat Masterson called Bill Tilghman "the greatest of us all." Theodore Roosevelt said he would "charge hell with a bucket."
Tilghman was one of the last of the old west lawmen. Unlike many of his contemporaries, he never crossed the line to the other side. Never even skirted it. He was everything in life that Masterson and the Earps and Wild Bill Hickock were in legend. He died in the line of duty at age seventy, shot to death by a corrupt a federal agent while trying to clean up an Oklahoma boom town.
Like many men of his time and place, Tilghman began as a buffalo hunter in the years after the Civil War, when the railroads were stretching across the prairie and cattle were trailing north from Texas. He found his way to Dodge City, where he opened a saloon, despite being a teetotaler, and got his first job as a lawman. It was also where he met Bat Masterson and Wyatt Earp.
In 1889, he moved to Guthrie. Over the next few years, he, Chris Madsen and Heck Thomas became known as the Three Guardsmen, deputy U.S. marshals who arrested around three hundred desperadoes over the next decade and killed several more. Tilghman's most famous exploit was the arrest of Bill Doolin in a Hot Springs, Ark., mineral bath.
Tilghman retired in 1910 and was elected to the state Senate, but resigned a year later to become Oklahoma City's police chief. In 1923, Gov. Martin Trapp persuaded Tilghman to come out of retirement a second time, to accept a special commission as marshal of Cromwell, a notorious unincorporated community in the Greater Seminole Oil Field known as the "wickedest city in the world." Cromwell had it all: prostitution, gambling, liquor and drugs. And one of the worst influences was a federal Prohibition officer named Wiley Lynn.
Lynn shot Tilghman twice on the night of Nov. 1, 1924, as they struggled for a gun. The old lawman died almost immediately. Typical of the times, Lynn was acquitted when several witnesses mysteriously disappeared; he and state Bureau of Investigation Agent Crockett Long shot each other to death eight years later in a Madill drug store.


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See "Colour Channel Usage" section, below.
Deep-blue Where it is desired to have a separate signal which controls the deep-blue intensity, this signal shall be supplied on the "User-defined signal 1" pair. When used this way, this is a unipolar analogue voltage whose range is 5 volts peak-to-peak differential.
Yellow Where it is desired to have a separate signal which controls the yellow intensity, this shall be supplied on the "User-defined signal 2" pair. When used this way, this is a unipolar analogue voltage whose range is 5 volts peak-to-peak differential.
Where it is desired to have a separate signal which controls the beam diameter, this shall be supplied on the "User-defined signal 3" pair. When used this way, this is a unipolar analogue voltage whose range is 5 volts peak-to-peak differential.
X-prime For stereoscopic applications where it is desired to have a separate signal for a second X scanner, this shall be supplied on the "User-defined signal 4" pair. When used this way, this signal shall represent the right-eye view and the "X" signal shall represent the left-eye view. The analogue voltage range and polarity are identical to the "X" signal.
Z For volumetric or stereoscopic applications where it is desired to have a separate signal which indicates depth, this shall be supplied on the "User-defined signal 4" pair. When used this way, this is a bipolar analogue voltage whose range is 10V peak-to-peak differential.
A differential voltage level of -10V shall represent "rear" or "far from the viewer". A differential voltage level of +10V shall represent "front" or "toward the viewer". A differential voltage level of 0V shall represent a neutral distance such as the plane of the screen.
Field Change For applications using sequential-field stereoscopic techniques, the field (selected polarization) shall be supplied on the "User-defined signal 4" pair. When used this way, this is a unipolar analogue voltage whose range is 5 volts peak-to-peak differential.


The Vapbong-philosophy about the life time and the spare parts you might need for this vapourizer is easy: A correctly used Vapbong vaporizer has to function a whole lifetime and the users should enjoy easy and inexpensive access to those spare parts that might need to be replaced over the years: the filters and the outer glass tube.
Every user can easily make and replace the filters of his or her Vapbong vaporizer. You only need a round pipe-screen made of brass with a diameter of 2cm (as commonly used for normal smoking pipes). Afterwards, just follow the instructions in the video about Vapbong vaporizer spare parts on www.vapbong.com. That's it.
You can always clean the soot, but a broken outer glass tube can't be used. That's why it's the only part of the device which is not made by us, you can purchase it everywhere. To replace the outer glass tube, search for stores that sell laboratory material and ask for a reinforced or Borosilicate 3.3 test-tube 12x75mm (inner diameter 10mm, length 75mm, outer diameter 12mm). That's it.
The filters and the test-tube will be rather inexpensive.


I call this method "the One Breath" and it was something I discovered during my practice.
At anything in life, you might have a hard time "getting started". Sometimes tasks overwhlem us, or we are just not in the right mind state to accomplish whatever it is we're trying to do.


How do I find the firmware version?
Master Lock codes: Sanyo SPC-5500: ##843461. Do you have any to add?????
How to share "wallet" photo?
How would you improve Sprint?
Ebay actors still at it.
Scott Stevenson makes my block senders list. Good job.
Something to avoid; Why won't my new phone receive calls???
THE LATEST PHONES FROM CEBiT!
Do new phones get better reception?
what can I do with a sprint PCS phone in Canada?
Program to get your MSL code: anyone tried this yet?


text:
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FAQ about Machinery Directive 2006/42/EC
Reading time: 6 minutes - Difficulty: medium
We will summarize the terms of the Machinery Directive 2006/42/EC in 8 simple points, examine when it applies, and see how it functions for the production of new machinery or for the use of work equipment built before and after the Directive was implemented.
1. What is the Machinery Directive?
Directive 2006/42/EC is the version of the Machinery Directive currently in force; the first version was drafted in 1989 (Directive 89/392/EEC) and subsequently revised in 1998 (Directive 98/37/EC).
The main purposes of the Machinery Directive are as follows:
to harmonize the health and safety requirements applicable to machinery, based on a high level of health and safety protection
to guarantee the free movement of machinery within the European market.
2. Field of application of the Machinery Directive
The general categories of products covered by the Directive are listed below:
interchangeable equipment
lifting apparatus
chains, ropes and straps designed and made for lifting purposes and serving as an integral part of lifting machinery or lifting accessories
removable mechanical transmission devices
partly completed machinery
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3. What is meant by machinery?
The Machinery Directive provides the following definition of "machinery" in
Article 2 Point 1: "An assembly, fitted with or intended to be fitted with a drive system other than directly applied human or animal effort, consisting of linked parts or components, at least one of which moves, and which are joined together for a specific application".
The Directive then extends the concept of machinery in further ways, also defining machinery as:
an assembly referred to in the first point, missing only the components to connect it on-site or to sources of energy and motion
an assembly referred to in the first and second points, ready to be installed and able to function as it stands only if mounted on a means of transport, or installed in a building or structure
assemblies of machinery, referred to in the three previous points, or partly completed machinery, which, in order to achieve the same end, are arranged and controlled so that they function as an integral whole
an assembly of linked parts or components, at least one of which moves and which are joined together, intended for lifting loads and whose only power source is directly applied human effort.
4. What is meant by partly completed machinery?
Article 2 of the Directive also contains the following definition of partly completed machinery:
"An assembly which is almost machinery but which cannot in itself perform a specific application. Partly completed machinery is only intended to be incorporated into or assembled with other machinery or other partly completed machinery or equipment, thereby forming machinery to which this Directive applies."
Since many manufacturers specialize in the production of single devices, with multiple final applications, it follows that much of the equipment on the market cannot be classed as "machinery" but more specifically as "partly completed machinery".
For more about the CE marking of partly completed machinery, see point 7 of this article.
The complete text of the Machinery Directive is available in PDF at the following link.
5. Are any categories excluded from the scope of the Directive?
Some types of equipment are covered by different regulations, and so are excluded from the terms of the Directive. They include:
seagoing vessels and mobile offshore units as well as machinery installed on board such vessels and/or units
mine winding gear
means of transport by air, on water and on rail networks, with the exclusion of machinery mounted on these means of transport
electrical and electronic products covered by the Low Voltage Directive (2014/35/EU)
all weapons (not just firearms)
agricultural and forestry tractors for the risks covered by Directive 2003/37/EC.
6. Contents of the Machinery Directive
The Directive lays down the essential health and safety requirements that products must meet at every stage of their design, manufacture and operation before being placed on the European market.
The Directive divides machinery into two large groups:
machines that must be certified by accredited third parties
machines that can be self-certified by the manufacturer.
The machinery included in Annex IV of the Directive must undergo a process of assessment by specific agencies (notified certification bodies) to confirm its compliance with the set health and safety requirements.
For all other types of machinery, the manufacturer is only required to draw up and keep the relevant technical file, in accordance with the instructions set out in Annex VII of the Directive itself.
Products placed on the market or subject to substantial changes after the Directive came into force must carry the appropriate marking and must be accompanied by a Declaration of Conformity (or a Declaration of Incorporation in the case of partly completed machinery).
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CE marking for machinery, in line with the standards of the European market
7. CE machinery certification
All machinery must be marked visibly, legibly and indelibly with the following minimum particulars in relation to CE certification:
the business name and full address of the manufacturer and, where applicable, his authorized representative
designation of the machinery
the "CE" marking (logo)
designation of series or type
serial number, if any
year of construction, that is the year in which the manufacturing process is completed
It is prohibited to pre-date or post-date the machinery when affixing the CE marking.
An important point needs to be made regarding partly completed machinery: these products must NOT carry the CE marking or logo as they are intended to be incorporated into more complex equipment, which will then be affixed with the appropriate CE marking at a later stage.
8. CE declaration of conformity for machinery
Every product placed on the market and subject to the Machinery Directive must be accompanied, for its entire useful life, by a CE Declaration of Conformity for machinery, issued by the manufacturer.
Annex II of the Directive outlines the minimum contents that must be included in this document, both for machinery and for partly completed machinery.
Once again, it is important to point out that the Directive makes a distinction between the two types of products; for in the case of partly completed machinery, the declaration not only serves the main function of identifying the product, but also provides the constructor incorporating the part with evidence that the essential safety requirements (ERS) have been subject to a risk analysis. The constructor will then have to assess all the ERS that the manufacturer of the product has been unable to meet, as the supplier of incomplete machinery.
Finally, to make a clear distinction between the two types of the document, the Directive identifies them in the following way:
Declaration of conformity, for machinery (Annex II-A)
Declaration of incorporation, for partly completed machinery (Annex II-B).
Do you need immediate assistance to ensure compliance with the essential safety requirements of the Machinery Directive?
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with the arrival of Memorial Day for many of us the patriotic season has arrived.
I started pulling out my red, white, and blue décor last weekend.
I was anxious to play with it after creating a patriotic craft at our last craft group.
Last March hubby and I took a road trip to Texas. We stayed a few days in the town of Brenham. That's where we discovered Blue Bell ice cream.
Not only was it delicious, but they sold their colorful cartons. After looking at them the thought came to me that they would make a fun base for an Americana scene.
I bought one for each member of the crafty bees. Yes, that's our name. :) The day of craft group we all brought odds and ends of Americana treasures and trinkets to share.
I noticed that I had a lot of vintage sewing notions that were red, white, and blue so I decided to create an 'ode to Betsy Ross'.
I added buttons, needle packets, ribbon, thread, and a flag. One member, Shirley brought us each a kit to make two pinwheels.
I bought the sweet little girl made from chenille bumps at a local store, Planted Earth.
Everybody's turned out so cute and unique!
This is my friend, Ann's. You can see the ice cream carton better in this photo.
Paula made a lot of things to go in hers. I copied images of my vintage sparkler boxes. She made her own box as well as a firecracker. Notice how she used her lid for a base?
The one in front and center is Margo's. She used a vintage reproduction card as her main point of interest.
Paula gave us each a bag of treasures. Joanne used the bingo card and tin man with the horn from it. I shared a few items I didn't use with her.
Kimi has the cutest little vintage girl in hers, and I love the picket fence around the bottom!
Shirley's is all ready to blast off with her fun firecrackers!
Mine has already found it's place on my kitchen table.
Thank goodness that I pick up and hang on to little treasures and trinkets for creating!
So cute! I have bits and bobs I need to get crafty with!
Jann, you were thinking ahead while in Brenham. Blue Bell is a staple in many a TX home, but I admit that we prefer Haagen-Dazs here. I know many that won't eat anything but Blue Bell! Your project was a great idea and each one turned out to be delightful. I admire your group of crafters. I didn't get my patriotic things out this weekend, but hope to soon.
Oh gosh, all you gals created gorgeous patriotic pretties! How very clever you all are!
Those are absolutely adorable! Now I want to make one!
This is so festive -- and seriously adorable!
Love all of them!!! Cute and festive.
They are all great! Fun too... Ready for the 4th of July and just in time for Memorial Day.
I have had blue bell ice cream and it is delish. Love all your creative memorial day and 4th decor. So festive and cute.
Those are all so cute, I just love to create things like that.
Crafter bees? Can I join the hive? I only have one good, local friend who loves to craft, decorate, tablescapes etc. How much fun it must bee to have a group who get together to make things.
So colorful and patriotic!How darling.Best wishes,Jann!
Love it all!! So festive and so vintage!!
As always Jann, you and your crafty friends amaze me!
This is really adorable Jann! So glad you linked up to our link up. Thank you so much!
This is adorable! So many cute things in those containers. Brenham is fun to visit. Thanks for linking up to Keep In Touch.


Home The Browning Letters [8 June 1846]. Browning, Elizabeth Barrett to Browning, Robert.
[8 June 1846]. Browning, Elizabeth Barrett to Browning, Robert.
Title [8 June 1846]. Browning, Elizabeth Barrett to Browning, Robert.


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Liberty is the result of our obsession for developing technical products driven by our limitless approach to design. Created on the principles of Swedish design with simplicity, minimalism and function fused with Swedish fashion. Liberty provides ultimate comfort in harsh conditions.
KJ Jacket is high persformance shell jacket in 3 layers stretch polyester. Developed together with WearColur's Family Kjersti Buaas, professional snowboarder from Norway. The blue colour represent the sky and will together with the hidden eye behind the bib remind you to be present. - We are as most present in our lifes in the nature, says Kjersti. The jacket features WearColurs PineTech membrane with 20K waterproofness and 15K breathability. The jacket is a fusion between an anorak and a jacket with clean Swedish design. All the features is strategically placed for optimal use and a zipper placed along the whole side for easier access. This jacket will help you stay stylish and flexible during all types of adventures. Contains recycled polyester and has a ecological impregnation free from perfluorinated compounds (PFC -free).
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**For stock items that are instock at Hyper Ride, excludes items from our distribution warehouse, please allow an extra 2-3 working days for products at our distribution warehouse. Once these have arrived at our Hyper Ride warehouse Express deliveries be sent asap.
All orders placed before 3pm Monday - Friday will leave same day if you choose Express Freight*, unless it says on the site ships in 1 - 2 working days. This means the item comes from a 3rd party, and will be despatched in 2 businesses days time.
No orders are shipped on Weekends, and public holidays.
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All orders will be shipped on our standard courier and will take 3-5 working days.
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Bic Surf 2018 Dura Tech Mini Mal Blue Checker 7'3"


text:
\section{\label{sec:intro}Introduction}
The presence of impurities usually deeply modify the nature of the
spectrum of a quantum system, and thus its coherence and transport
properties.  In the absence of interactions, if the impurity
distribution is completely random, all states of the spectrum are
exponentially localized in dimensions one (1D) and two (2D), while a
mobility edge exists in dimensions three
(3D)\cite{Ande58,Ande79,Akkermans2007}.  If the impurity positions are
correlated, as for instance if it exists a minimum distance between
the impurities \cite{schaff10,Larcher2013}, some delocalized states
can appear in the spectrum. This was demonstrated in 1D in the context
of the Random Dimer Model (RDM) and of the Dual Random Dimer Model
(DRDM) \cite{Phil90}. In 1D, the effects of correlated disorder was
studied in different physical contexts (see for instance
\cite{deMour98,Izrailev1999,Tessieri2002,Kuhl08,Luga09}).  In 2D, the
effect of correlations is almost unexplored, except for the case of a
speckle potential \cite{Kuhn07}, and for the case of
pseudo-2D random dimer lattices with separable
dimensions \cite{Naether2015}. Correlations in speckle potentials
may mimic the presence of a mobility edge \cite{Luga09}, but
in the thermodynamic limit all states are localized \cite{Kuhn07}.
Random dimers introduce a set of delocalized states in
pseudo-2D lattices \cite{Naether2015} as in 1D \cite{Phil90}.
From a statistical point of view, the main difference between these two models
is the decay of the correlation function that is algebraic for the first
and exponential for the second. This ``short-range'' feature of the
random dimer model is at the basis of the delocalization mechanism.

In interacting systems, the presence of disordered impurities gives
rise to a remarkable richness of phenomena. For instance, the
condensate and the superfluid fraction are modified by the presence of
the disorder \cite{Astra2002,Buonsante2009}, and this can shift the
onset of superfluidity \cite{Pilati2010,Plisson2011,Allard2012}, and,
on lattice systems, can induce exotic phases such as the Bose glass
\cite{Fisher1989}.

In this work we study the effect of a short-range correlated disorder on
a Bose gas confined on a 2D square lattice. First we introduce a 2D
generalization of the DRDM (2D-DRDM).  In such a model, impurities
cannot be first neighbours and each impurity also modifies the hopping
with its nearest neighbor sites.  Using a decimation and
renormalization procedure \cite{Farchioni1992a}, we show that, in the
non-interacting regime, it exists a resonance energy at which the
structured impurity is transparent and the states around this energy
are delocalized.  It is remarkable that this resonance energy does not
depend on the system dimensionality and it is the same as the DRDM
in 1D~\cite{Phil90,schaff10}.  Then, we consider the case of a weakly
interacting Bose gas confined on such a potential.  Within a
Gutzwiller approach, we show that the effect of the 2D-DRDM is to
drive the homogeneity of the ground state. The disorder induces a
non-monotonic behavior of the condensate spatial delocalization and
of the condensate fraction as a function of the disorder strength, and
enhances both in correspondence of the resonance energy of 2D-DRDM
single-particle Hamiltonian. We show that the dependence of such
quantities on the interaction strength can be explained by including
the effect of the healing length in the resonance condition
discussion.

The manuscript is organized as follows. In Sec. \ref{sec:model}, we
introduce the 2D-DRDM potential and we demonstrate its single-particle
delocalization properties in the region of the spectrum around the
resonance energy.  The effect of such a potential on a
weakly-interacting Bose gas is studied in Sec. \ref{sec:results},
where we also introduce a suitable inverse participation ratio for our
many-body system and study it for the case of the 2D-DRDM potential
and for an uncorrelated random disorder. Moreover, we compute the
density distribution and the condensate fraction as functions of the
disorder strength.  Our concluding remarks in Sec. \ref{sec:concl}
complete this work.

\section{\label{sec:model} The DRDM in two dimensions}
We consider the tight-binding single-particle Hamiltonian
\begin{equation}
  H=-\sum_{\langle ij \rangle}t_{ij}\left(|i\rangle\langle j|+ |j\rangle\langle i|\right)+
  \sum_{i=1}^N \varepsilon_i |i\rangle\langle i|
\end{equation}
where $\varepsilon_i$ are the on-site energies, $t_{ij}$ the
first neighbor hopping terms, $N$ the number of sites and
$\langle ij \rangle$ denotes the sum over first neighbor sites.

We focus on a 2D square lattice of linear dimension $L$ ($N=L^2$
lattice sites), and compare the ordered lattice with $\varepsilon_i=0$
and $t_{ij}=t$ $\forall$ $\langle i j\rangle$, as schematized in
Fig.~\ref{fig1}(a) with a lattice where we introduce an impurity at
the site 0, $\varepsilon_0=\Delta$ that modifies the hopping terms
involving this site, $t_{0,j}=t'$ [Fig.~\ref{fig1}(b)].
\begin{figure}
\begin{center}
\includegraphics[width=0.9\linewidth]{fig1.eps}
\caption{\label{fig1} Schematic representation of (a) the unperturbed
  Hamiltonian; (b) the Hamiltonian in the presence of a single
  impurity; (c) the effective Hamiltonian after decimation of the site
  0 in the Hamiltonian (a); (d) the effective Hamiltonian after
  decimation of the site 0 in the Hamiltonian (b).}
\end{center}
\end{figure}
\subsection{Effect of correlations in the single-particle spectrum}
With the aim of understanding the effect of the impurity, we consider
the Green's function $G_{AA}(E)=\langle A|(E-H)^{-1}|A\rangle$ projected on
the subspace $A$, including all sites except the site $0$
with coordinates $(0,0)$.
Using a decimation and renormalization technique \cite{Farchioni1992a},
it can be shown that
\begin{equation}
G_{AA}(E)=(E-H_{eff})^{-1}
\end{equation}
with
\begin{equation}
H_{eff}=\left\{\begin{array}{ll}
H_{AA}+\dfrac{t_{0,j}^2}{E-\varepsilon_0}&\phantom{bla}{\rm if}\;j\;{\rm is\;a\;first\!-\!neighbour}\\[-2mm]
&\phantom{bla}{\rm site\;of\;the\;site\;}0\\[1mm]
H_{AA}&\phantom{bla}{\rm elsewhere}
\end{array}\right.
\end{equation}
where $H_{AA}=\langle A|H|A\rangle$. The effective Hamiltonian for the
unperturbed case in Fig. \ref{fig1} (a), is schematically illustrated
in Fig. \ref{fig1} (c); whereas the effective Hamiltonian for the case
with a single impurity in Fig. \ref{fig1} (b), is illustrated in Fig.\
\ref{fig1} (d).  The subspace $A$ does not ``feel'' the presence of
the impurity if $G_{AA}$ ($H_{eff}$) remains the same in the absence
or in the presence of the impurity, namely if
\begin{equation}
\dfrac{t^2}{E}=\dfrac{(t')^2}{E-\Delta}.
\label{condition}
\end{equation}
The condition (\ref{condition}) is satisfied if
$E=E_{res}=-\dfrac{\Delta}{(t'/t)^2-1}$. If $E_{res}$ is an allowed energy
of the system, namely if $-4t<E_{res}<4t$, at $E=E_{res}$ the impurity
will not affect the eigenstate at this energy (in the subspace $A$).

If we add other impurities in the system, as the one in
Fig. \ref{fig1} (b), with the supplementary condition that on-site
impurities cannot occupy first neighbor sites (Fig. \ref{fig2}), one
can repeat the same argument as above, properly redefining the
subspace $A$, and one obtains exactly the same condition
(\ref{condition}) imposing that {\it all} the $N_{imp}$ impurities do
not perturb the system (the subspace $A$).  Thus at $E=E_{res}$, the
impurities are transparent as in the 1D DRDM~\cite{Phil90}.  Indeed,
with this procedure, we are defining a 2D-DRDM, where at each
``isolated'' impurity correspond a structure of 4 hopping terms
forming a cross, as shown in Fig.~\ref{fig2}. Let us remark that this
definition of the model provides the same condition (\ref{condition})
independently from the dimensionality of the system
\cite{Phil90,schaff10}. However our model is fully 2D and the Hamiltonian
cannot be mapped onto two 1D DRDM as opposed to Ref. \cite{Naether2015}.

\begin{figure}
\begin{center}
\includegraphics[width=0.8\linewidth]{fig2.eps}
\caption{\label{fig2} Schematic representation of the 2D DRDM.}
\end{center}
\end{figure}

With the aim of analyzing the localization properties of this model,
we consider the Inverse Participation Ratio (IPR)
\begin{equation}
  \mathcal{I}(E)=\left\langle\dfrac{\sum_i |\psi_i(E)|^4}{(\sum_i |\psi_i(E)|^2)^2}\right\rangle.
\label{eq:ipr}
\end{equation}
The symbol $\langle\dots\rangle$ denotes the average over different
disorder configurations, and $\psi_i(E)$ the wavefunction on site $i$ and
at energy $E$.  If $E_\alpha$ is an eigenvalue of the system
and $\psi_i(E=E_\alpha)$ is an extended state, then $\mathcal{I}$
decreases as a function of $L$.  On the other side, if
$\psi_i(E_\alpha)$ is a localized state, then $\mathcal{I}$ does not
depend on $L$ (if $L$ is larger than the localization length).  In
Fig. \ref{fig3} we show the behavior of $\ln(\mathcal{I})$ and
$\ln(\mathcal{I}\,L^2)$ (column left and right respectively), for the
Hamiltonian illustrated in Fig. \ref{fig2}.
\begin{figure*}
\begin{center}
\begin{tabular}{cc}
\includegraphics[width=0.45\linewidth]{fig3topleft.eps} &
\includegraphics[width=0.45\linewidth]{fig3topright.eps} \\
\includegraphics[width=0.45\linewidth]{fig3middleleft.eps}&
\includegraphics[width=0.45\linewidth]{fig3middleright.eps} \\
\includegraphics[width=0.45\linewidth]{fig3botleft.eps}&
\includegraphics[width=0.45\linewidth]{fig3botright.eps}
\end{tabular}
\end{center}
\caption{\label{fig3} (Color online) Inverse participation ratio
  ($\ln(\mathcal{I})$ left column and $\ln(\mathcal{I}\,L^2)$ right
  column) as a function of the energy $E$ in units of $t$. The plots
  in the first row correspond to $\Delta/t=0.44$ and $t'/t=1.2$; in
  the second row correspond to $\Delta/t=3$ and $t'/t=2$; and in the
  the third row to $\Delta/t=8$ and $t'/t=3$. The different curves in
  each plot correspond to different system sizes: $L=20$ (red), 30
  (green), 40 (blue) and 50 (magenta).  Each curve correspond to
  $N_{imp}/N\simeq 0.15$ and to an average over 50 configurations.
  The data are binned in 80 (first row) and 110 bins (second and third
  rows). The vertical dashed lines indicate $E_{res}$.}
\end{figure*}

We consider three set of parameters, (i) $\Delta/t=0.44$ and
$t'/t=1.2$, (ii) $\Delta/t=3$ and $t'/t=2$, and (iii) $\Delta/t=8$ and
$t'/t=3$ that give the same resonance energy, $E_{res}/t=-1$.  In all
the three cases, the curves $\ln(\mathcal{I}(E)\,L^2)$ collapse around
$E=E_{res}$ meaning that the states are delocalized in this energy
region. Moreover, due to the large strength of the disorder,
the spectrum varies considerably for the cases (ii) and (iii),
and an energy gap appears in (iii).

The inverse participation ratio, Eq.~(\ref{eq:ipr}), in two dimensions has the
following asymptotic behavior~\cite{murphy2011}
\begin{equation}
\lim_{L\rightarrow\infty}\mathcal{I}(E)=\left\{%
  \begin{matrix}
    1/L^2 & \text{(extended states)} \\
    \text{const.} & \text{(localized states)}\,. \\
  \end{matrix}\right.
\end{equation}
Thus, the asymptotic behavior of the function $\mathcal{I}(E)\,L^2$ is
\begin{equation}
  \lim_{L\rightarrow\infty}\mathcal{I}(E)\,L^2= L^d\,,
  \label{eq:asymPatty}
\end{equation}
with $d=2$ for localized states, and $d=0$ for extended states. In
Fig.~\ref{fig:esponenti} we have analyzed the exponent $d$ as a
function of the energy for the set of parameters (iii). We observe a
high-energy band of localized states that has been created by the
disorder; the original (without noise) band has been distorted, and
the states at its boundaries are localized. The center of the band,
around $E_{res}$, is mainly constituted of extended states.
The width of the feature around $E_{res}$
corresponds to the width of the resonance dip of the inverse
participation ratio at this energy value (Fig. \ref{fig3}).

\begin{figure}
  \begin{center}
    \includegraphics[width=0.9\linewidth]{fig4.eps}
    \caption{The exponent of Eq.~(\ref{eq:asymPatty}) as a function of
      the energy for $\Delta/t=8$ and $t'/t=3$. The exponent has been
      obtained using calculations for lattice-linear dimensions
      $L=40,50,60,70,80,90,100$ averaged over 20 realizations,
      the error bars correspond to the standard deviation of the
      fit of the data to Eq.\ (\ref{eq:asymPatty}).  The vertical
      dashed line indicates $E_{res}$.}
\label{fig:esponenti}
  \end{center}
\end{figure}

These results confirm that our 2D extension of the DRDM introduced by
Dunlap and collaborators in Ref.~\cite{Phil90} for 1D systems
introduces a set of delocalized states even at higher dimensions.

\section{\label{sec:results} Effects of the interactions}
We now consider the case of weakly interacting bosons in the presence
of the potential defined in Sec. \ref{sec:model}.  This system is
described by the Bose-Hubbard Hamiltonian in the grand canonical
ensemble
\begin{equation}
  H_{BH}=-\sum_{\langle ij \rangle}t_{ij}(\hat a_i^\dagger\hat a_j+\hat a_j^\dagger \hat a_i)-
  \sum_i(\mu-\varepsilon_i)\hat{n}_i+\dfrac{U}{2}\sum_i \hat{n}_i(\hat{n}_i-1)
\label{eq:BHGW}
\end{equation}
where $\hat a_i^{\dagger}$ is the creation operator defined at the
lattice site $i$, $\hat{n}_i=\hat a_i^\dagger\hat a_i$, $U$ the
interparticle on-site interaction strength, and $\mu$ denotes the
chemical potential fixing the average number of bosons.

We use a Gutzwiller approach to find the ground state wavefunction for
a given set of parameters and average number of particles. The
Gutzwiller ansatz is given by the site product wavefunction in the
occupation number representation
\begin{equation}
|\Phi_{\mathrm{GS}}\rangle = \prod_i^{L\times L} \sum_{n_i} f_i(n_i)|n_i\rangle,
\end{equation}
where $f_i(n_i)$ are the probability amplitudes of finding $n_i$
particles on site $i$. The ansatz provides an interpolating
approximation correctly describing both the Bose-condensed and
Mott-insulating phases for low and high $U$, respectively, in
dimensions larger than one.  In addition, the approximation becomes
exact for all $U$ in the limit of infinite dimensions
\cite{Rokhsar1991,Metzner1990}.

We minimize the average energy given by Hamiltonian (\ref{eq:BHGW}) as
a function of the set of amplitudes $f_i(n_i)$ with the normalization
and average number of particle constraint for at least 30 disorder
realizations for each set of parameters. The minimization is done
using standard conjugate-gradient and/or Broyden-Fisher techniques
\cite{Press2007} which provides reasonable performance for moderate
lattice sizes.

\subsection{Characterization of the condensate delocalization}
To quantify the extent of delocalization of the ground state
$|\Phi_{\mathrm{GS}}\rangle$ in the interacting regime, we decompose
it onto the localized basis $|\psi_i\rangle$,
$|\Phi_{\mathrm{GS}}\rangle=\sum_i c_i |\psi_i\rangle$, representing
the distribution of a homogeneous condensate with average density $n$
on the lattice \cite{Dukesz2009}. We define the many-body ground-state
IPR $\mathcal{I}_{\mathrm{GS}}$ with respect to this basis as
\begin{equation}
  \mathcal{I}_{\mathrm{GS}}=\left\langle\dfrac{\sum\limits_{i=1}^{N}c_i^4}{(\sum\limits_{i=1}^{N}c_i^2)^2}\right\rangle.
\label{eq:IPRGS}
\end{equation}
$\mathcal{I}_{\mathrm{GS}}$ measures the homogeneity of the ground
state in the condensation regime: the smaller
$\mathcal{I}_{\mathrm{GS}}$ the more spatially delocalized is the
condensate.

In Fig.\ \ref{fig:IGS_L20} we show the behavior of
$\mathcal{I}_{\mathrm{GS}}$ as a function of $\Delta$, by fixing
$L=20$, $U/t=10^{-2}$ and $n=20$, for several values of $t'$.
\begin{figure}
\includegraphics[width=0.9\linewidth]{fig5.eps}
\caption{\label{fig:IGS_L20}(Color online)
$\mathcal{I}_{\mathrm{GS}}L^2$ as a function of $\Delta/t$
for $L=20$, $U/t=10^{-2}$ and $n=20$ particles per site.
The different curves correspond to different values of $t'$ as indicated
in the figure.
The filled symbols correspond to the 2D-DRDM potential and the empty
symbols correspond to the UN-RAND potential.}
\end{figure}
We compare the case of $22\%$ of correlated impurities $N_{imp}$ with
the one of the same percentage of uncorrelated impurities, where there
is no restriction for the position distribution of the on-site
impurities $\Delta$ and no correlations between them and the
additional hopping $t'$ (UN-RAND). We note that due to the
correlations present in the 2D-DRDM the maximum percentage of allowed
impurities is $50\%$ (in this limit the system would be an ordered
checkerboard). We can observe that, in the case of the 2D-DRDM
potential, $\mathcal{I}_{\mathrm{GS}}$ has a minimum as a function of
$\Delta$, whose position depends on the value of $t'$.  This
non-monotonic behavior is a signature of the resonance induced by the
correlations of the disordered potential.  Indeed, it disappears for
the case of the UN-RAND potential and for large values of $t'$ (strong
disorder). The dip in the $\mathcal{I}_{\mathrm{GS}}$ for the UN-RAND
potential and weak disorder ($t'/t=1.2$) indicates that some DRDM
impurities may still statistically appear, in the absence of
correlations. The effect of such impurities is not fully destroyed by
the other defects only if the strength of the disorder is weak.

\subsubsection{The resonance effect as a function of the interactions}
In the perturbative regime for negligible interactions, one would
expect that correlations modify the ground state if
$E_{res}=E_{\mathrm{GS}}$, $E_{\mathrm{GS}}$ being the ground-state
energy per particle, which corresponds to $\simeq -4t$ in the weak
disorder regime.  This condition, that can be written
\begin{equation}
\Delta=4t[(t'/t)^2-1],
\label{cond-pat}
\end{equation}
determines the location of the minimum of $\mathcal{I}_{\mathrm{GS}}$
at $\Delta/t=1.67$ for $t'/t=1.2$, $\Delta/t=12$ for $t'/t=2$, and
$\Delta/t=32$ for $t'/t=3$. However, in the limit of strong disorder,
due to the interactions these
values strongly differ from those shown in
Fig.~\ref{fig:IGS_L20}. In fact, we calculate $\mathcal{I}_{\mathrm{GS}}$ for
smaller values of $n$ and verify that the minimum location of
$\mathcal{I}_{\mathrm{GS}}$ depends on $E_{res}$ and that the shift observed is
indeed an effect of the interactions. The results are illustrated in
Fig.~\ref{fig:IGS_L20_N}, where we focus on the case $t'/t=2$.
\begin{figure}
\includegraphics[width=0.90\linewidth]{fig6.eps}
\caption{\label{fig:IGS_L20_N}(Color online)
  $\mathcal{I}_{\mathrm{GS}}L^2$ as a function of $\Delta/t$ for
  $L=20$, $U=10^{-2}t$ and $t'/t=2$.  The different curves correspond
  to different values of the average density $n$ as indicated in the
  figure.  All the curves correspond to the 2D-DRDM potential.
  The vertical dashed line indicates the non-interacting resonance
condition given in Eq. (\ref{cond-pat}).}
\end{figure}
By decreasing the value of $n$, the minimum position $\Delta_{min}/t$
of $\mathcal{I}_{\mathrm{GS}}$ shifts from $6.5$ to about $12$ as
expected by the perturbative argument.  This shift can be understood
as follows. The interactions introduce the so-called healing length
$\xi=\sqrt{t/(2nU)}$ \cite{Bukov2014} that represents a coherence
length over which the system feels the effect of an impurity, or in
other words, the distance a site affects its neighborhood. For
$U/t=10^{-2}$ and $n$ from 20 to 5, the value of $\xi$ ranges
approximately from $1.5$ to 3 lattice spacing $\ell$, which shows that,
already for this $U$ value, the role of the interactions is important,
effectively reducing the coherence length.  To quantify this effect,
we can partition the system into independent boxes of dimension
$\xi\times\xi$, and use a mode-matching argument to determine their
ground states: the condensate is more homogeneous if the lowest
eigenvalue of each box is the same despite the presence of an
impurity.

\begin{figure}
\includegraphics[width=0.6\linewidth]{fig7.eps}
\caption{\label{figboxes}(Color online)''Boxes'' of different sizes,
in the presence and in the absence of an impurity.}
\end{figure}
Therefore, this mode-matching argument fixes the value of $\Delta$.
  For the case $U/t=10^{-2}$ and $n=20$,
$\xi\simeq 1.6\ell$, and this gives $4.24<\Delta/t<6$ while for $n=5$,
$\xi\simeq 3.2\ell$, and we expect to find $8.4<\Delta/t<12$, in good
agreement with the results showed in Fig.~\ref{fig:IGS_L20_N}.
Namely, the larger is $\xi$, the better we recover the non-interacting
condition Eq. (\ref{cond-pat}). This effect is summarized in Table
\ref{tab:Uloco}.
\begin{table}
  \caption{\label{tab:Uloco}Effective linear dimensions $\xi$ and positions of
the expected resonance $\Delta$ for the weakly interacting bosons in the
2D-DRDM. }
\begin{center}
\tabcolsep=6pt
\begin{tabular}{ccc}
\hline
\hline
$ \xi$ &Fig. & $\Delta$
  \\ \hline  \\
$\ell$ &\ref{figboxes}(a)&$\sqrt{2}t\,[(t'/t)^2-1]$\\[5pt]
$2\ell$&
\ref{figboxes}(b)&\; $2t\,\,[(t'/t)^2-1]$\\[5pt]
$2\sqrt{2}\ell$&
 \ref{figboxes}(c)& $2\sqrt{2}t[(t'/t)^2-1]$ \\[5pt]
\hline \hline
\end{tabular}
\end{center}
\end{table}

We remark that this mode-matching condition is equivalent to match the
resonance energy $E_{res}$ with the lowest eigenvalue of the
unperturbed system of size $\xi\times\xi$.  These simple arguments,
allow us to understand the shift of $\Delta$ as a function of the
interaction energy $Un$ and the role of the structured impurities
in the presence of the interactions.

\subsubsection{The resonance effect as a function of the system size}

We study the scaling behavior of $\mathcal{I}_{\mathrm{GS}}L^2$ with respect
to $L$.  Analogously to the case of the single-particle IPR
$\mathcal{I}(E)$ [see Eq. (\ref{eq:asymPatty})], we expect that
\begin{equation}
  \lim_{L\rightarrow\infty}\mathcal{I}_{\mathrm{GS}}\,L^2= L^d\,,
  \label{eq:asymPatty2}
\end{equation}
with $d=2$ for a condensate localized on few sites, and $d=0$
for a homogeneous extended condensate.
The behavior of $\mathcal{I}_{\mathrm{GS}}L^2$ for different values of $L$
is shown in Fig. \ref{fig:IGS_L}.
\begin{figure}
\includegraphics[width=0.93\linewidth]{fig8.eps}
\caption{\label{fig:IGS_L} (Color online)
  $\mathcal{I}_{\mathrm{GS}}L^2$ as a function of $\Delta/t$ for
  $t'/t=2$, $U/t=10^{-2}$ and $n=20$ particles per site. The different
  curves correspond to different values of $L$ as indicated in the
  figure.  The filled symbols correspond to the 2D-DRDM potential and
  the empty symbols correspond to the UN-RAND potential.}
\end{figure}
We observe that the minima, corresponding to different system sizes,
collapse all together, meaning that the ground state corresponds to a
spatial homogeneous condensate in the parameter regime where the
correlations are dominant.  At lower values of $\Delta$,
$\mathcal{I}_{\mathrm{GS}}L^2$ scales as $L^{-\epsilon}$, and larger
values of $\Delta$, $\mathcal{I}_{\mathrm{GS}}L^2$ scales as
$L^{\epsilon'}$, with $\epsilon$ and $\epsilon'$ $>0$.  This sort of
``super-delocalization'', in the low $\Delta$ region, is determined by
the large value of $t'$ that compensates, in the structured impurities,
the effect of the site defect.  Indeed, we observe
an analogous behavior for the UN-RAND potential. For such a
potential, where the effect of $t'$ is no more dominant, all the
curves collapse together. Thus we expect that in this region the
effect of the uncorrelated impurities on the ground state
density distribution does not depend on the system size.

\subsection{Condensate delocalization and condensate fraction}
With the aim of characterizing the ground state configurations in the
different regions, we show in Figs.
\ref{fig:denlatt2.1}--\ref{fig:denlatt15.1} the spatial density
distribution $n_i$ for $L=20$, $n=20$ at $\Delta/t\simeq 2$
(Fig.~\ref{fig:denlatt2.1}),
$\Delta/t \simeq 6.6$ (Fig.~\ref{fig:denlatt6.6}),
and $\Delta/t\simeq 15$ (Fig.~\ref{fig:denlatt15.1}) together with
a pattern showing the
locations of impurities.

\begin{figure}
\centering
\includegraphics[width=0.9\linewidth]{fig9top.eps}\\
\includegraphics[width=0.9\linewidth]{fig9bot.eps}
\caption{\label{fig:denlatt2.1}(Color online) Lattice density plots
  together with site and bond impurities locations for $t'/t=2$,
  $\Delta/t\simeq2$ and DRDM disorder (top) and UN-RAND (bottom).}
\end{figure}

\begin{figure}
\centering
\includegraphics[width=0.9\linewidth]{fig10top.eps}\\
\includegraphics[width=0.9\linewidth]{fig10bot.eps}
\caption{\label{fig:denlatt6.6}(Color online) Same as Fig.\
  \ref{fig:denlatt6.6} for $\Delta/t=6.6$.}
\end{figure}

\begin{figure}
\centering
\includegraphics[width=0.9\linewidth]{fig11top.eps}\\
\includegraphics[width=0.9\linewidth]{fig11bot.eps}
\caption{\label{fig:denlatt15.1}(Color online) Same as Fig.\
  \ref{fig:denlatt6.6} for $\Delta/t=15.1$.}
\end{figure}
The addition of a hopping term $t'$ favors the delocalization of the
density both for the 2D-DRDM and UN-RAND disorders. However, in the
case of the 2D-DRDM, it is more beneficial as it tends to partially
compensate the decrease in the density caused by the site impurity,
reducing the decrease by means of the structured disorder.  For small
values of $\Delta$ (see Fig.\ \ref{fig:denlatt2.1}), in the region
where the effect of $t'$ is dominant, the density in the impurity
regions is even larger with respect to the density elsewhere.  For
large values of $\Delta$ (see Fig.\ \ref{fig:denlatt15.1}), the effect
of both types of disorder is similar as the change in the on-site
energies dominates. This limit gives rise to a strongly depleted
density at the impurity location plus a rather uniform background.
The largest differences among the 2D-DRDM and UN-RAND results are seen
at the minimum of $\mathcal{I}_{\mathrm{GS}}$ (see Fig.\
\ref{fig:denlatt6.6}), where we can clearly observe a more homogeneous
density spread over the lattice (lower $\mathcal{I}_{\mathrm{GS}}$),
and a consequently larger delocalization for the 2D-DRDM than for the
UN-RAND potential.

The density behavior determines the condensate fraction
$n_c=\sum_i|\langle \Phi_{\mathrm{GS}}|a_i |\Phi_{\mathrm{GS}} \rangle|^2/n$,
as shown in Fig. \ref{fig:N0_L}.
\begin{figure}
\includegraphics[width=0.9\linewidth]{fig12.eps}
\caption{\label{fig:N0_L}(Color online) Condensate fraction $n_c$ as a
  function of $\Delta/t$ for $t'/t=2$, $U/t=10^{-2}$ and $n=20$
  particles per site. The different curves correspond to different
  values of $L$ as indicated in the figure.  The filled symbols
  correspond to the 2D-DRDM potential and the empty symbols correspond
  to the UN-RAND potential.}
\end{figure}
In correspondence of the minimum of the function
$\mathcal{I}_{\mathrm{GS}}$, we observe that the condensate fraction
$n_c$ does not depends of the system size, in the presence of the
2D-DRDM potential. The resonance condition minimizes the
fluctuations with respect the chosen homogeneous basis
$|\psi_i\rangle$ and fixes $n_c$.
At lower value of $\Delta$, we observe
a ``super-delocalization'' ($\mathcal{I}_{\mathrm{GS}}L^2$ scales as
$L^{-\epsilon}$), and for both the 2D-DRDM and the UN-RAND potentials,
the large value of $t'$ enhances the coherence and $n_c$ increases
with system size.

At larger values of $\Delta$, where
$\mathcal{I}_{\mathrm{GS}}L^2$ scales as $L^{\epsilon'}$, the 2D-DRDM
impurities create holes in the system, and $n_c$ decreases with system
size.  For the case of the UN-RAND potential, one can observe a
monotonic behavior of $n_c$ as a function of $\Delta$. As for the case
of the 2D-DRDM, the region where all the curves
$\mathcal{I}_{\mathrm{GS}}L^2$ collapse together corresponds to a
region where $n_c$ does not depend on the system size. The difference
with the 2D-DRDM is a larger decrease of $n_c$ in this
region. For 2D-DRDM, only one value of $\Delta$ has this peculiarity,
and the maximum position of the condensate fraction foregoes this
point. Let us remark
that the minimum of $\mathcal{I}_{GS}$ corresponds to the minimum deviation
with respect a homogeneous condensate, and, because of border effects,
this target state is not necessarily the one that ensures a maximum
value of $n_c$ in finite systems.

The predicted condensate fraction enhancement for the DRDM at low $\Delta$,
being it very small, could be very difficult to be measured.
However the non-diminishing of the coherence in a range
of about $5\Delta$ should be observable, and could be directly
compared with the result for the UN-RAND where the decrease of the
coherence should be sizable.

\section{Conclusions}
\label{sec:concl}
In summary, we introduce a correlated disorder model that is the
natural extension of the DRDM in 2D. We show that, in the
non-interacting regime, such a disorder introduces some delocalized
states if the resonance energy characterizing these structures belongs
to the spectrum of the unperturbed system.  In the presence of weak
interactions, the 2D-DRDM drives the density spatial fluctuations.  By
means of a mode-matching argument that includes the effect of the
interactions, we show that the resonance energy is at the origin of
these phenomena. A direct consequence is a non-monotonic behavior of
the condensate fraction as a function of the disorder strength, and
its enhancement for values close to the resonance condition.  This
work shows that short-range correlations in a disordered potential can
modify and enhance the coherence of a many-body system in the weak
interacting regime. Such effects could be measured in the context of
ultracold atoms with an accurate measurement of the density and
coherence, via, for instance, a fringes contrast interference
experiment. Our results could also be extended to homogeneous systems
provided one is able to engineer suitable impurities that are
transparent for a given energy.

\begin{acknowledgments}
  This work was supported by CNRS PICS grant No. 05922.  PC
  acknowledges partial financial support from ANPCyT grant PICT 2011-01217.
\end{acknowledgments}

redpajama_set_name: RedPajamaArXiv


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