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Review of Potential Energy Storage in Abandoned Mines in Poland
Interlayer Microstructure Analysis of the Transition Zone in the Silicon/Perovskite Tandem Solar Cell
Social Responsibility of Economic Units and the Well-Being of Society in the Tourism Sector: Example of Accommodation Facility
Monolithic Perovskite-Carrier Selective Contact Silicon Tandem Solar Cells Using Molybdenum Oxide as a Hole Selective Layer
Cuma Tyszkiewicz
Swatowska, B.
Powroźnik, W.
Czternastek, H.
Lewińska, G.
Stapiński, T.
Pietruszka, R.
Witkowski, B. S.
Godlewski, M.
Application Properties of ZnO and AZO Thin Films Obtained by the ALD Method
Barbara Swatowska
Wiesław Powroźnik
Halina Czternastek
Gabriela Lewińska
Tomasz Stapiński
Rafał Pietruszka
Bartłomiej S. Witkowski
Marek Godlewski
Department of Electronics, Faculty of Computer Science, Electronics and Telecommunications, AGH University of Science and Technology, 30-059 Krakow, Poland
Institute of Physics, Pedagogical University of Cracow, ul. Podchorążych 2, 30-084 Krakow, Poland
Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
Energies 2021, 14(19), 6271; https://doi.org/10.3390/en14196271
(This article belongs to the Special Issue Recent Advances in Thin Film Solar Cells)
The thin layers of ZnO and ZnO: Al (Al doped zinc oxide—AZO) were deposited by the atomic deposition layer (ALD) method on silicon and glass substrates. The structures were deposited using diethylzinc (DEZ) and deionized water as zinc and oxygen precursors. A precursor of trimethylaluminum (TMA) was used to introduce the aluminum dopant. The present study of ALD-deposited ZnO and AZO films was motivated by their applications in photovoltaics. We attempted to expose several properties of such films. Structural, optical (including ellipsometric measurements) and electrical investigations were performed. We discussed the relations between samples doped with different Al fractions and their properties.
AZO thin films; ALD technique; optical properties; structural properties; electrical parameters
Zinc oxide (ZnO) is one of the most popular semiconductor materials with a wide band gap equal to 3.27 eV at room temperature, with an exciton binding energy of 60 meV, but most of all, with a free electron concentration regulated in a wide range, up to 1020 cm−3 [1,2,3]. Due to such properties, ZnO-based thin layers can be used as the transparent conducting oxide (TCO) in solar cells and in ultraviolet light emitters [1,2,3].
ZnO films when used for TCO applications [4] can replace the widely used indium tin oxide (ITO). Even though ITO layers are still superior—they have high conductivity and optical transparency in the wide range of the solar spectrum [4,5]—their price becomes too high due to the increasing price of indium. This fact started an active search for alternative TCO materials [4,6]. One of the most promising alternative TCO materials is ZnO, in particular when doped with Al (AZO), Ga (GZO), In (IZO) or F (FZO) [4].
In the present study we concentrate on AZO films deposited by the atomic layer deposition (ALD) technique. Such films can be deposited using a variety of techniques, including most of all magnetron sputtering [7], pulsed laser deposition [8], chemical vapor deposition [9] and sol–gel deposition [10,11].
To select the growth method of ZnO (AZO) films, several parameters must be taken into account, especially the required TCO parameters [12], but also price, the possibility of low temperature growth and scalability to large substrates as well. This is why PLD is not used in industrial processes despite the best electrical parameters of the PLD films. Magnetron sputtering is the most commonly used deposition technique. The so-obtained layers show resistivity on the order of 10−4 Ω cm, with optical transparency >80% in the visible spectrum [13]. The reported AZO film resistivity and transparency (above 80% in the visible light range) are very close to those of ITO. Thus, AZO films are successfully used as transparent electrodes in silicon-based (see e.g., [14]) or copper indium gallium diselenide (CIGS) solar cells [15].
Recently, ALD technology has attracted a lot of attention. Increasing interest in ALD is related to the unique capability with the possibility of deposition of pinhole free conformal layers on flat or textured surface, low temperature deposition and scalability to large surfaces [16,17,18]. Properties of ZnO films grown by ALD at low temperature (LT) were discussed by us in detail in our previous works [19,20]. Due to the self-limited growth rate, the layer thickness can be controlled with a precision of ~1 nm by controlling the number of ALD cycles. The combination of these features allows for the production of new, unique and nano-scale optoelectronic devices [21]. However, despite the first industrial applications, basic research is still needed to understand the dependencies between growth parameters and structural, electrical and optical properties of the films. The latter is well documented by our investigations of ALD-grown ZnO films in which we observed a range of puzzling film properties both for ZnO [22,23,24], as well as AZO films [25,26]. We list here only a few puzzling properties of these films. For example, why does the growth mode of AZO films change with an increase of Al fraction in the films [25]? Is the growth epitaxial or it is depositional [23]? Why do we observe a large shift of an optical band gap with increasing Al fraction in the films [25]?
This work attempts to clear up some of these questions. ZnO layers and Al doped ZnO layers with different concentrations of Al are grown using ALD and doping procedures described in the literature [25,26]. These layers were tested by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), optical spectrophotometry and spectroscopic ellipsometry (SE). Electrical measurements (Hall effect studies) were also performed to obtain data on electron concentration and their mobility.
2.1. Sample Preparation
ALD layers were deposited on silicon and glass substrates. A high-resistance 4″ (100) Czochralski silicon wafer (Cz-Si) was cut into pieces of size 1 × 1 cm2 for SEM measurement and 2.5 × 2.5 cm2 for structural measurements (XRD and ellipsometry). The glass substrates (bought from Carl Rothe, Karlsruhe, Germany, id. 0656.1) were cut into pieces of size 2.5 × 2.5 cm2 for optical study. Prior to deposition processes, the substrates were cleaned using our standard procedure, first in acetone, and then in isopropanol and deionized water for 5 min in an ultrasonic cleaner. After cleaning, the samples were blow-dried using 5N purity nitrogen.
ALD Layer Deposition
The layers were deposited on silicon and glass substrates using a Beneq TSF 200 commercial ALD reactor. A rotary vane pump allowed us to keep the pressure in the growth chamber at ~3 × 10−1 Torr. The temperature during the growth of all samples was kept at 160 °C. Our earlier investigations indicated that films deposited at this temperature are of a relatively good crystallographic quality and show relatively high free electron concentrations and low deep defect concentrations [23,24]. A higher temperature (200 °C) was used in a previous study [25,26]. The zinc oxide and aluminum doped zinc oxide layers were grown using diethylzinc (DEZ; CAS: 557-20-0) and trimethylaluminum (TMA; CAS: 75-24-1) as zinc and aluminum precursors, respectively. Deionized water was used as the precursor of oxygen [25,26]. During the growth process, diethylzinc, trimethylaluminum and deionized water were kept at room temperature (22 ± 2 °C). These precursors were sequentially introduced into the growth chamber using pure nitrogen (5N purity) as a carrier gas. Each ALD cycle included four steps: (i) pulse of the first reagent (precursor), (ii) purge of the growth chamber by an inert gas, (iii) pulse of the second reagent, (iv) purge of the growth chamber by an inert gas. We used 1 s or 2 s purging times. This may have affected the growth mode of the layers since we found that for longer purging times (we tested for times up to 12 s) the growth on the c-axis perpendicular to the surface was preferential [23]. The technological details of layer growth are summarized in Table 1.
A zinc oxide layer was deposited introducing the DEZ and H2O precursors alternately. For the growth of AZO layers, the following solution was used: To obtain the AZO layer, m (DEZ + H2O → ZnO) cycles were separated by one (TMA + H2O → Al2O3) cycle. In this case, m equaled 7, 9, 19 and 29. This approach allowed us to obtain a ZnO layer with different Al dopant concentrations. If the number of m is small, the aluminum content in the ZnO is high. As the value of m increases, the concentration of dopant decreases. To initiate growth, we started first with a TMA pulse, as in our previous study [25,26]. Figure 1 shown below shows the method of doping in the ALD technology.
ALD "supercycle" was repeated to obtain films with about 200 nm thickness.
2.2. Measurement Techniques
A NanoCalc 2000 thin film reflectometer (Ocean Optics, Inc., Rochester, NY, USA) was used to measure the thickness of the layers deposited on Si. Additionally, the thickness of each film was determined from SEM cross-section images. These values were then confirmed by ellipsometric measurements. The cross sections, top view images and EDS spectra were measured using a Hitachi SU-70 scanning electron microscope (SEM), at an accelerating voltage of 5 kV (EDS) and 15 kV (images). For these investigations, films deposited on silicon substrates were used.
An X'pert MPD (Panalytical) X-ray diffractometer (A.P. Instruments Sp.z o.o. Sp.k., Warszawa, Poland) with CuKα = 1.5425 Å radiation was used to investigate the structural properties of thin films of ZnO and AZO deposited on Si substrates. The θ/2θ scans of the films were collected in the 2θ angle range from 25 to 115 degrees.
The electrical parameters of zinc oxide (ZnO) and aluminum doped zinc oxide (AZO) were measured by RT Hall in the van der Pauw configuration. A permanent magnet from RH2035PhysTech system provided a magnetic field of 0.4 T. Hall measurements were carried out on layers deposited onto glass substrates (1 × 1 cm2) to avoid the influence of Si substrate on electrical parameters.
The variable angle spectroscopic ellipsometry measurements for four incident angles, namely 60°, 65°, 70° and 75°, were carried out using a spectroscopic ellipsometer (M-2000, J.A. Woollam Co. Inc., Lincoln, NE, USA) following the method described in [27,28,29]. The measurements of Ψ—amplitude component, and Δ—phase shift as a function of wavelength λ, in the range from 300 to 1700 nm provided refractive index n and extinction coefficient k dispersion relations. The ellipsometric modeling was performed using Complete EASE Data Acquisition and Analysis Software for Spectroscopic Ellipsometers (J.A. Woolam Co. Inc., Lincoln, NE, USA) [30].
Optical transmission and reflectance of ZnO and AZO layers were measured by means of a Perkin-Elmer Lambda 19 spectrophotometer (PerkinElmer Polska sp. z o.o., Krakow, Poland) (range from 250 to 1700 nm).
The first important question to be answered was if the "doping" method" used by us (sequences of pulses of two metal precursors) really leads to Al doped films. Importantly, we did not used postgrowth annealing as in reference [26] to improve Al inter-diffusion. To answer this question, we performed EDS investigations of AZO films deposited on an Si substrate. Elemental composition of the analyzed structures, as determined from EDS investigations (different areas of samples were tested), are listed in Table 2.
Considering the accuracy of the method (about 2%), we looked for Zn/O, Al/Zn and (Zn + Al)/O ratios of the films (Table 2).
Analyzing the results given in Table 2, we see that within the method accuracy, the films showed a good stoichiometry ((Zn + Al)/O ratio close to 1) but better for films with a larger Al fraction (m smaller). The Al/Zn ratio for m equal to 29 and 19 followed the ratio of ALD sequences.However, if the Al fraction was increased (samples AZO-3 and AZO-4), we observed deviation between Al/Zn and 1/m. It looks like more reactive Al started to dominate and replace Zn. Formation of foreign phases may have occurred, limiting the "doping" method used in ALD.
Our previous investigations suggested that the increased fraction of Al affects also the growth mode of sample and sample crystallinity [25]. To verify/confirm this observation, we performed SEM (cross section images and top view) and XRD investigations. The relevant results are shown below. In Figure 2 we show the SEM images of ZnO and AZO layers deposited by the ALD at the conditions given in Table 2. A cross section on the left and top view on the right of the figure are presented, respectively. The results were compared with the ones obtained by us previously for the films grown at higher temperature [25]. Despite a lower growth temperature and considerably shorter purging times, they were quite similar. The ZnO layer grown at 160 °C showed columnar growth with a dominant c-axis orientation perpendicular to the surface of the films. Large grains (column diameters) were also observed.
A quite different surface morphology was observed for the AZO samples. For AZO samples, the growth was more chaotic with many of the columns in the plane of samples. Moreover, the grains size was diminishing as the Al concentration was increasing. For the AZO-4 sample, the majority of columns was in the plane of the sample, and an amorphous-like structure started to dominate, similarly as reported by us in reference [25].
To confirm this observation, we performed XRD investigations of AZO samples. The XRD patterns collected for AZO thin films prepared with different Al concentrations are shown in Figure 3. The crystalline state and crystal orientation of the films in fact changed with Al concentration, confirming the conclusions from SEM studies.
Undoped ZnO film exhibits a hexagonal structure. The sample was polycrystalline with randomly orientated grains showing (100), (002), (101) and (110) XRD peaks, with the (002) being the strongest [31]. As we investigated previously to obtain monocrystalline films, we needed a higher growth temperature [19] and longer purging times [23]. As Al2O3 interlayers were introduced (the method of doping with Al), the (002) XRD peak faded away, and the intensity of the (100) peak became dominant, with the maximum for a low Al fraction sample (1.6% Al). Evolution of ZnO peaks showed that introducing the Al2O3 interlayer affected the (002) growth, and the (100) XRD peak appeared to be the preferred growth direction. Similar results were reported by us [26] and in the references [32,33] for samples grown at slightly different conditions. It seems thus that the trend reported above is common for samples with Al.
The (100) and (110) ZnO peak parameters were analyzed, as these peaks were observed for all investigated Al concentrations. The 2θ position of both (100) and (110) peaks increased with increasing Al concentration in AZO films (Figure 4c). This indicates that the addition of Al to the ZnO layer reduced the inter-planar spacing in the (100) and (110) directions. It can be attributed to Al3+ ions vicariously replacing Zn2+ at random sites. In this context, the difference in the values of the ionic radius was important. The Zn2+ ionic radius was 72 pm, whereas that of the Al3+ was 54 pm. By the above, inter-planar distances can be reduced [30].
The total area of the (100) and (110) ZnO peaks (Figure 4a) had a maximal value at Al concentration equal to 1.6% and decreased as Al concentration increased to 7.9%. The grain size calculated for the (100) peak (we used the Scherrer approach [34,35] reached the maximum at 1.6–2.5 of at.% Al and then decreased, while for the (110) peak, it decreased as the at.% Al changed from 0 to 7.9% (see Figure 4b). Concluding, as the content of Al increased, the grains became smaller, and the diffraction peaks became weaker, i.e., the crystallization of AZO deteriorated, as also observed previously. In conclusion, when the Al content increased to 7.9%, AZO sampled tended to amorphize, the grains became smaller, and the diffraction peaks weakened. This is in line with the SEM results [25,26,33].
Doping with Al is a way to improve sample conductivity to make them suitable for TCO applications. We thus looked for the efficiency of doping. The electrical parameters of ZnO and AZO layers determined from Hall measurements are shown in Table 3.
For the pure ZnO layer, the concentration of carriers at the level of 1018 cm−3, mobility 16.4 cm2/Vs and resistivity of 10−2 Ω cm were observed. These results were in line with the ones commonly reported by us for the ALD-grown ZnO films [20,22,24]. Aluminum doping of ZnO films improved their electrical properties, but only for low Al fractions. The relevant results are shown in Figure 5.
Figure 5 shows the variation of electrical resistivity ρ, carrier density n and Hall mobility μ as a function of the Al content in the films. With increasing Al content, the resistivity of the AZO films initially decreased up to 0.005 Ω.cm. This variation in resistivity was due to an increase in free carrier concentration as a result of electron released from the Al donors. Substitutional incorporation of Al3+ ions (after ionization of electrons) for Zn2+ cations was responsible for a marked enhancement of carrier concentration. However, interstitial doping could not be excluded. A broad minimum in resistivity was located between 1.5 and 6 at.% of Al. When the Al content exceeded 6 at.% of Al, ρ started to increase. This effect might be a result of clustering in a nonconducting form of Al2O3 related to the crystal disorder. The excess of Al entailed charge trapping rather than donor action. Such a possibility was suggested previously [32,36,37]. This is a possible explanation of the drop in free electron concentration. However, if created, the concentration of such traps must be low, since these clusters are not observed in the XRD investigations.
Another explanation was proposed in reference [25]. The decrease in the carrier concentration could have been due to compensation effects, i.e., because of native defects formation. From Figure 5, we can see that zinc content gradually decreased with increases in the Al content in the films. For the highest concentrations of Al dopant, this decline is significant. According to Kröger–Vink notation, when a small amount of Al2O3 is dissolved in ZnO [38], the Al atoms substitute the Zn sites:
A l 2 O 3 → 2 Z n O 2 A l Z n ˙ + 2 O O x + O i ″
and when the larger amount of Al-dopant atoms is introduced into the ZnO matrix, the defect reaction is
A l 2 O 3 → 3 Z n O 2 A l Z n ˙ + 3 O O x + Z n i ″ + 2 V Z n ″
The increase in Al-doping level induced zinc interstitial (Zni) and zinc vacancy (VZn). It is likely that a large number of zinc vacancies will be created because their formation energy is relatively low [39]. The second expression shows that oxygen vacancies arise in the range of a higher level of doping with Al atoms. In addition, according to Wang et al. [40], higher doping levels of Al dopants reduced the formation energy of (VZn). Formation of such centers and likely of Al-VZn complexes may explain the decreased n-type doping efficiency. Furthermore, their high concentration should also affect the absorption spectrum, as discussed below.
The excess aluminum doping reduced the carrier concentration in the films. A consequence of this was an increase in resistivity. In Figure 6 is illustrated the decrease in the Hall mobility of the AZO films versus increases in Al content. The observed decrease in grain size of the AZO films as it was seen in the SEM images and from XRD data (Figure 2 and Figure 4b) also influenced carrier mobility. The decrease in the grain size increased grain boundary scattering, thus decreasing carrier mobility. Increased concentration of scattering centers (Al donors) also contributed to the mobility decrease.
For small values of Al content in layers, the concentration n increased and the Hall mobility μ decreased. After about 4% of Al content, both n and μ decreased, but n definitely faster. We had to thus find an optimum between an increased free electron concentration and the drop of carrier mobility. The lowest resistivity was found for relatively low Al fractions in the samples—say between 2% and 6%. Moreover, this result differed from that reported previously [25]. In this reference a much sharper dependence of film resistivity on Al fraction was reported.
For TCO applications, the sample should be highly conductive but also transparent in a visible light range. We thus verified sample transparency after Al doping and determined the extinction parameters, which should be low for the films applied as transparent electrodes.
To determine the effect of Al doping on the optical properties of the films, we used two different measurement methods: ellipsometric spectroscopy (SE) (for the ZnO and AZO films deposited onto Si substrates), and transmission and reflection spectroscopy (T–R) in the case of films deposited onto glass substrates.
For the analysis and interpretation of ZnO and AZO thin films and optical properties, a multilayer model was used, in which the substrate was silicon (from the program library), and the investigated layer was fit using the general oscillator (GO) model. To obtain the dispersion relationships of optical constants n and k in oxides, the most popular model is the Cauchy model (the simplest model for nonabsorbing layers) [41]; oxide layers are also modeled using the Tanguy model [42], the Drude model [43] and the oscillator model [44,45]. Two Tauc–Lorentz oscillators were used [46]. The Tauc–Lorentz equation is as follows [47]:
ε T − L ( E ) = ε n 1 + i ε n 2
ε n 2 ( E ) = [ A m p n E 0 n B r n ( E − E g n ) 2 ( E 2 − E 0 n 2 ) 2 + B r n 2 E 2 ⋅ 1 E ] when E > E g n
ε n 2 ( E ) = 0 when E ≤ E g n
ε n 1 = 2 π P ∫ E g n ∞ ξ ε n 2 ( ξ ) ξ 2 − E 2 d ξ
where ε1 is the real part of dielectric function, and ε2 is the imaginary part of dielectric function; the four fitting parameters are Eg, Ampn, E0 and Br, and all are in units of energy (eV); P stands for the Cauchy principal part of the integral (Compleate EASETM Data Manual J.A. Woolam Co., Inc.). A parameterization of the optical functions of the material is connected with the imaginary part of the dielectric function and the Tauc density of states.
The dispersion relation of the refractive index n(λ) with dielectric function and thickness of the layers were determined from the analysis of the data. The thickness determined from ellipsometric measurements was between 214 and 233 nm, i.e., very close to the intended thicknesses of the films based on the number of ALD "supercycles". The latter means that the growth rate was relatively weakly affected by the change of the m value and the fact that we used the same growth conditions for ZnO and Al2O3 deposition. Slightly thicker films were obtained when the m value was reduced, i.e., the number of Al2O3 cycles was increased.
The determined spectral dispersion of refractive index n (on the basis of SE measurements) for five samples is presented in Figure 7.
The transmission spectra of ZnO and AZO1–4 films were also measured by use of a Perkin-Elmer spectrophotometer (T–R measurements). The obtained results are presented in Figure 8. All films were transparent with the average transmission in the visible light region (~85%). The absorption edge shifted towards higher energies with the increase of Al content, as we already reported previously [25].
A fit was performed to the experimental data. The Cauchy model was used. It describes the dispersion relation of refractive index n and extinction coefficient k of dielectric materials and semiconductors with relations described by Equations (5) and (6) [48]:
n ( λ ) = A + B λ 2 + C λ 4
k ( λ ) = D ⋅ exp { E [ 12400 ( 1 λ − 1 F ) ] }
The model is adjusted using the A, B and C parameters. As D is marked the extinction coefficient amplitude, the exponent factor is labeled E and the band edge is tagged F. Due to the consideration of band gap absorption at the edge of the band gap, this empirical model is useful for ZnO thin films [49]. Film Wizard (Scientific Computing International, Carlsbad, CA, USA) software was used to analyze the transmission and reflection spectra. The three-phase model was applied to describe the material configuration, i.e., air/ZnO film/glass substrate where the glass substrate was 0.5 mm thick. The typical fitting results of the transmission and reflection spectra are shown in Figure 9.
Figure 10a,b show the variations of refractive index n and extinction coefficient k of the films with different aluminum contents for the spectral range 300–800 nm. For ZnO and Al-doped ZnO films, there was a noticeable increase in refractive index with increasing wavelength, but then (for longer wavelengths) it slowly decreased. These changes resulted from the increase and decrease in optical absorption. The reduction to zero extinction coefficient above 450 nm was significant, which makes the material suitable for TCO applications.
The n index in the weak absorption region (for λ larger than 400 nm) decreased progressively with the increase of Al fraction. This can be related to the known fact that Al impurity in ZnO acts as an effective n-type donor; thus, doping leads to the generation of free carriers. As the Al content increased, the carrier concentration in the AZO layers increased. The enhancement of carrier concentration resulted in the decrease of refractive index [50]. For selected applications, the ability to control and change n of AZO films by changing the aluminum content is important.
Table 4 contains the values of thickness and refractive index of ZnO and AZO films, calculated on the basis of both kinds of optical measurements: SE and T–R.
The optical energy gaps were estimated by using the equation for a direct allowed type band-to-band transition:
( α h ν ) 2 = A ( E − E g )
where A is a constant, Eg is the optical energy gap and α = 4πk/λ is the optical absorption coefficient; α can be calculated from the extinction coefficient k.
Figure 11 shows a plot of (αhυ)2 vs. the photon energy. The linear fitting allowed us to determine the sharp absorption edge of the AZO layers. The point where (αhυ)2 equals zero indicates the Eg. This procedure may lead to some errors, since for larger Al fractions, we observed a relative long tail at lower energies, and the linear part of the plot was relatively short.
Despite some limitations of the method of Eg estimation, it was seen (see Figure 11) that the absorption edge shifted to the shorter wavelength region (larger energies) with increasing Al content. Similar results reported previously [25] were explained (for lower Al fractions) by the Burstein–Moss effect [51]. This is in line with the observed metallic-like conductivity of heavily doped AZO films. The widening of the optical band is related to the fact that optical transitions can only take place between the valence band and states in the conduction band above the Fermi level, which itself is related to the fact that states below the Fermi level are occupied by electrons.
Until now we used the language of doping, but once Al fraction is up to nearly 8% it is more like alloying than doping. Surprisingly, the results shown in Figure 12 were in line with this possibility. The optical band gap increased linearly with the Al fraction in the sample. The explanation of the observed large shift of the optical band gap by Burstein–Moss effect only is thus confusing.
To clear up this confusing situation, we repeated the approach used previously by us in reference [24]. The Burstein–Moss effect predicts the following relationship between an optical energy gap and a carrier concentration:
Δ E B M = ( h 2 8 m * ) ( 3 n π ) 2 3
where h is Planck's constant, m* is the effective mass of the electron and n is the carrier concentration.
As can be seen from Figure 13, this dependence was valid up to 2.5 at.% of Al only. In addition to the Burstein–Moss band filling, band gap renormalization effects should also be taken into account. Band gap renormalization results from many body interactions and causes bandgap narrowing. The Jain model [52], which can be taken to estimate bandgap renormalization, is binding for AZO films also [53]. Based on Jain's analyses [52], the gap narrowing may be expressed in the form of EBGN = An1/3 + Bn1/4 + Cn1/2. The n1/3, n1/4 and n1/2 dependencies correspond to the exchange energy of free electrons, their correlation energy and the electron–ion interaction energy, respectively. A and B coefficients are theoretically calculated, and C is a fitting parameter. However, in our case only three points were available for the calculations (up to 2.5 at.% Al), which made it difficult to compare the contributions of Burstein–Moss and band gap narrowing effects to the variation of band gap values with respect to electron concentration. That is why we gave up on the calculations with little data availability.
Above 2.5 at.% of Al doping, the Eg does not depend linearly on n2/3. There is a decrease in n as Eg increases further. This indicates a change in the creation of free carriers in the AZO layers. A model assuming alloy formation is not also supported by the that the Al/Zn ratio followed the ratio of ALD sequences only for m parameter equal to 29 and 19 (see Table 2). However, if the Al fraction increases (samples AZO-3 and AZO-4), we observe a deviation between Al/Zn and 1/m. One possibility is that formation of foreign phases may occur, limiting the "doping" method used in the ALD. If such foreign phases (e.g., Al2O3) are formed, their concentration must be low, below the detection limit of the XRD. Summarizing, the observed large shift of the optical band gap still remains puzzling, with the Burstein–Moss effect possible but only for samples with low Al fractions.
ALD technology enables precise control of Al content in AZO layers for films grown with Al fractions of up to 3%. Unfortunately, the layer morphology and electrical parameters strongly depend on Al content in the AZO films grown by the ALD. The samples with Al fractions above ~3% tend to be more disordered, the columnar ZnO structure is no longer observed and the resistivity of samples increases instead of decreasing. The large increase of the optical band gap is observed, but the explanation of this effect is not straightforward. Only for the AZO films with low Al fractions can the Burstein–Moss effect be observed. Differences in the activity of Al and Zn may account for the observed problems with uniform doping/alloying films with larger Al fractions. Nevertheless AZO films with Al fractions up to 2–3% show the required optical and electrical properties for their use in photovoltaics as transparent electrodes. It is also likely that samples with larger Al fractions may be useful (e.g., for transparent electrodes in UV LEDs), but their preparation must be optimized. Post-growth annealing may be useful, since it improves Al distribution in the films [26].
Conceptualization: M.G., T.S. and R.P.; Formal analysis: B.S., T.S., R.P. and M.G.; Investigation: B.S., W.P., H.C., G.L., R.P. and B.S.W.; Methodology: H.C., T.S., B.S.W. and M.G.; Project administration: M.G.; Validation: B.S.; Visualization: B.S.; Writing – original draft: R.P., M.G., T.S. and B.S.; Writing – review & editing: B.S. All authors have read and agreed to the published version of the manuscript.
This work was partially supported by the Polish Ministry of Science and Higher Education under subvention funds of the Department Institutional Review Board Statement of Electronics of AGH University of Science and Technology (AGH grant number 16.16.230.434) and by the National Centre for Research and Development project TECHMATSTRATEG1/347012/NCBR/2017 and TECHMATSTRATEG1/347431/14/NCBR/2018.
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Figure 1. Doping procedure used in ALD technology to obtain AZO films.
Figure 2. The SEM images of cross section (left column) and top view (right column) of ZnO and AZO layers on Si substrates.
Figure 3. The XRD patterns collected for AZO films prepared with different Al concentration levels.
Figure 4. (a) The total peak area; (b) the grain size and (c) 2θ position of the (100) and (110) ZnO peaks, as a function of Al concentration (at.%).
Figure 5. Relation between chemical composition of ZnO and AZO films on Al atomic content.
Figure 6. Dependence of electrical resistivity ρ, carrier density n and Hall mobility μ on Al content in the AZO films.
Figure 7. Spectral dependence of refractive index for samples with different contents of aluminum, from ellipsometric measurements (SE) using the general oscillator (GO) model.
Figure 8. Transmission spectra of pure and Al-doped ZnO films on glass substrate at different Al contents.
Figure 9. Transmission and reflection spectra vs. wavelength for sample AZO-4 (Al content 7.9%); experimental and calculated data (on the basis of Cauchy model).
Figure 10. The spectral dependences of: (a) the refractive index n and (b) the extinction coefficient k, obtained by the use of the Cauchy model.
Figure 11. Energy gap for analyzed thin films, detected from Formula (7).
Figure 12. Optical band gap as a function of Al content in the analyzed films.
Figure 13. Optical band gap vs. (carrier concentration n)2/3 for AZO films.
Table 1. The ALD growth parameters of ZnO and AZO layers.
Reagent
Pulse (s)
Purge (s)
Ratio of ALD Cycles
ZnO DEZ 0.04 1
H2O 0.02 1
AZO TMA 0.04 1 1:m
(1 × TMA + H2O + m × DEZ + H2O)
DEZ 0.04 1
Table 2. Values of m (DEZ + H2O → ZnO) cycles and elemental composition of thin ZnO and AZO layers obtained by the ALD method on silicon substrates.
ZnO
AZO-1
m 0 29 19 9 7
Al (%) 0 1.6 2.5 6.3 7.9
Zn (%) 54.2 51.4 50.5 45.1 42.8
O (%) 45.8 47.0 47.0 48.6 49.3
Zn/O ratio 1.19 1.09 1.07 0.93 0.87
Al/Zn ratio 0 0.03 0.05 0.14 0.18
(Zn + Al)/O ratio 1.19 1.13 1.13 1.06 1.03
1/m - 0.03 0.05 0.11 0.14
Table 3. Electrical parameters and band gap of ZnO and AZO layers with different Al concentrations, measured at room temperature (ρ—resistivity; μ—mobility of carriers; n—concentration of electrons; Eg—band gap).
ρ (Ωcm) 4.93 × 10−2 7.59 × 10−3 6.33 × 10−3 2.04 × 10−2 9.98 × 10−2
μ (cm2/Vs) 16.4 9.5 7.3 3.0 1.33
n (cm−3) 7.70 × 1018 8.66 × 1019 1.34 × 1020 1.01 × 1020 5.22 × 1019
Eg (eV) 3.33 3.48 3.56 3.78 3.88
Table 4. Main parameters from optical measurements (T–R and SE).
Al Content (at.%)
Thickness from T–R (nm)
Thickness from SE (nm)
n from T–R for 600 nm
n from SE for 600 nm (on Base GO Model)
ZnO 0 214 214 2.01 1.98
AZO-1 1.6 211 218 1.92 1.93
Swatowska, B.; Powroźnik, W.; Czternastek, H.; Lewińska, G.; Stapiński, T.; Pietruszka, R.; Witkowski, B.S.; Godlewski, M. Application Properties of ZnO and AZO Thin Films Obtained by the ALD Method. Energies 2021, 14, 6271. https://doi.org/10.3390/en14196271
Swatowska B, Powroźnik W, Czternastek H, Lewińska G, Stapiński T, Pietruszka R, Witkowski BS, Godlewski M. Application Properties of ZnO and AZO Thin Films Obtained by the ALD Method. Energies. 2021; 14(19):6271. https://doi.org/10.3390/en14196271
Swatowska, Barbara, Wiesław Powroźnik, Halina Czternastek, Gabriela Lewińska, Tomasz Stapiński, Rafał Pietruszka, Bartłomiej S. Witkowski, and Marek Godlewski. 2021. "Application Properties of ZnO and AZO Thin Films Obtained by the ALD Method" Energies 14, no. 19: 6271. https://doi.org/10.3390/en14196271
Energies, EISSN 1996-1073, Published by MDPI


Coordination of Benefits: COB rules can be set per insurance plan as well as a global default. COB.
EOB scanning: Insurance Payments have a place to attach scanned EOBs for later reference. Finalize Insurance Payment.
Command-line Arguments: Many more command-line arguments added so that specific Open Dental databases, users, and patients may be launched from batch files, from shortcuts, and from other programs. Command-line.
Central Enterprise Management Tool: Customers with multiple locations and separate databases now have a way to magage and interact with those separate databases from a centralized tool. Central Manager.
Popups for Family: Popups can now be family level or even superfamily level. Multiple popups per patient and/or family. Popups.
Billing default messages for email subject and body. Billing.
Email statement fields: nameF, nameFL, PatNum. Billing.
CC recurring charges can be applied to payment plans. Recurring Charges.
Security permission for changing subscriber on existing plan. Security.
Chart module Progress Notes, order of rows has been overhauled. Show Tab Chart.
Appointment views, when show ops for sched provs, clinic filter added. Appointment Views.
UB04 claimform now included. Medical Ins.
FeeSchedules can no longer be hidden if in use by a Provider. Fee Schedules.
Claimform 1500 now part of database for everyone rather than requiring a download.
Clinics: Filter recall list, confirmation list, unscheduled list, and billing list. Appointment Lists.


Bureau of Automotive Repair home page. This Google translation feature is provided for informational purposes only as DCA is unable to guarantee the accuracy of this translation.
The Bureau strives to protect and serve California consumers by ensuring a fair and competitive automotive repair marketplace and administering a model motor vehicle emissions reduction program.
The latest Tweets from Bureau of Automotive Repair (@BARinfo). Official Twitter account for the California Bureau of Automotive Repair. We can also be reached at (800) 952-5210.
Bureau of Automotive Repair home page. Disclaimer for Disciplinary Action and Citations The reports contained as part of this web site represent summaries of those formal orders issued by the Department of Consumer Affairs (DCA) and its participating programs, boards, committees, and commissions, imposing citations, suspension, revocation or other discipline.
The Bureau of Automotive Repair (BAR) is committed to providing access to our web pages for individuals with disabilities. If you have difficulty accessing any material on this site for any reason, please contact us in writing or via telephone and we will work with you to make the information available.


A leading philosopher has published what is believed to be the secret of how one can find true love.
Famous Israeli philosopher Aaron Ben-Ze'ev has argued in his forthcoming book that most of the popular ways to look for lifelong love are not good enough.
Ben-Ze'ev offers in his book "The Arc of Love" a unique approach on how to gain and maintain an enduring loving relationship.
The most crucial step is how to choose the right person.
The book will be released in June 2019 in the U.S. and Xinhua was the first to review the book and its ideas.
Ben-Ze'ev is the former president of the Israeli University of Haifa and founding president of European Philosophical Society for the study of emotions.
He told Xinhua that building the foundations of deep love is difficult and challenging. However, an enduring love can be achieved.
There are four common ways to judge the potential romantic companion. The first will be the checklist method focused on superficial negative qualities. The second is love at first sight which refers to superficial positive attributes. The third method seeks to identify a major flaw in a personality, and once it was detected, the candidate is dropped. This approach offers more accurate results than the checklist, according to Ben-Ze'ev.
The fourth strategy is to observe partners' interactions and notice whether a partner brings out the best in the companion and help him or her to flourish in their daily life. "Today, the greatest weight is commonly given to the first and second methods, then to the third and in the end, to the fourth. The order should be reversed without neglecting any information gained in each method," said Ben-Ze'ev.
One fundamental aspect of choosing a romantic partner is the weight that we give to bad and good qualities of the potential spouse. Negative emotions and bad feedbacks have more impacts than good ones. Accordingly, we are more motivated to avoid bad events than to pursue good ones. Establishing a checklist of desired qualities for a partner is a common practice, but it has massive flaws.
Love cannot be computed merely by mechanistically detecting separate negative and positive attributes. It is hard to detect positive qualities that are valuable for the long-term relationship, partly because they are more clearly revealed through shared activities that take place over time. It is ineffective to try to predict a successful relationship merely by calculating a partner's qualities by following the checklist method.
As no one is perfect, it may often be easier to detect negative qualities in everyone than positive ones. On the other hand, people may get accustomed to the lack of positive characteristics. If we reject all those who have some flaws, we might remain single for the rest of our life, or end up marrying a person who has fewer positive qualities rather than someone we met at the beginning of our search. Therefore, if you realize that your potential partner is likely to bring out the best in you, you have a perfect reason to choose this person as your life companion. Although romantic love is vital for our happiness, love is neither a necessary nor a sufficient condition for a happy and thriving life. As it turns out, love is not all you need in life, though it is often a central part of it.
Aaron Ben-Ze'ev was born in Israel. He is married to Ruth and has two sons, Dean and Adam.
He received his B.A. in Philosophy and Economics (1975) and his M.A. in Philosophy (1977), both from the University of Haifa.
He was awarded his Ph.D. from the University of Chicago (1981).). His doctoral thesis was entitled "Perception as a Cognitive System".
Five years after finishing his Ph.D. thesis, Ben-Ze'ev began to study the emotions, a topic that remains at the centre of his research today.
In this field he was particularly influenced by Aristotle (mainly his analysis of emotions as evaluative attitudes) and by Spinoza (in particular, his emphasis on the importance of change in generating emotions). The psychological work that has most influenced his thinking has been The Cognitive Structure of Emotions (1988) by Ortony, Clore and Collins.
Ben-Ze'ev has published many articles in this field, as well as several books.


A history of American politics and its paranoid strain - from the beginning of the republic to Donald Trump and his campaign for the Republican presidential nomination.
"In politics, you campaign in poetry and govern in prose," said Mario Cuomo, former governor of New York and perpetual presidential hope of liberal Democrats.
But was Mario right? In America, politicians very often campaign on fear. And when that fear is stoked to irrational levels, it has a clinical name - paranoia.
Fifty years ago in a classic essay, American political scientist Richard Hofstadter, explored the Paranoid Style - "an old and recurrent phenomenon in our public life which has been frequently linked with movements of suspicious discontent". In this documentary, Michael Goldfarb looks at the history of America's politics of paranoia backwards from Donald Trump's current campaign through the McCarthy era to the foundation era of the US and fears of Freemasons and the Illuminati seizing control of the government.
Using archive recordings and readings, as well as interviews with leading historians and political operatives, Goldfarb explains how exploiting irrational fear became a major part of American politics.


Dr. Kinney grew up in Phoenix, the youngest of four children, and at the age of four informed her mother, after visiting her own doctor, that she would be the first doctor for animals. It was all success from that point forward. Determined to excel amongst her older siblings, she skipped third grade and had barely turned 17 when she started attending college at the University of Arizona. She then completed her undergraduate requirements in three years and traveled to Washington State University where she earned her Doctorate of Veterinary Medicine. She stayed an additional year after her doctorate to complete an internship in anesthesiology where she studied this subject at a deep level and had an opportunity to work with a variety of species.
Always attracted to beautiful outdoor places and the smaller, more rural areas of our state, it was an easy decision for her to come to Sedona. She has been at OCSAC for twenty years, the longest of any veterinarian in our region, and is the owner of our practice. Dr. Kinney has a deeply rooted love for animals and nature, and an aptitude for science and education. She is committed to staying current in veterinary medicine and is the only regional member of the Arizona Academy of Veterinary Practice, an elite group of Arizona veterinarians for whom membership requires five times the state requirement annually of continuing education. She is constantly spending time off expanding her knowledge. Most recently she has studied advanced dentistry and surgical techniques, new advancements in veterinary cancer treatment, and internal medicine developments. One of her own dogs is participating in a ground-breaking study which will hopefully enhance the lives of thousands of dogs in the future who share his disease. Her next goal is completing a rigorous trek to become a Certified Canine Rehabilitation Practitioner. (She'll be able to rehabilitate felines and other species, too!) On her wish list for Santa this year is an underwater treadmill for our excitedly anticipated new hospital. She prioritizes investing in new equipment and improved technology to better provide for her patients. She also regularly contracts with various specialists to provide continuing education to the entire staff on-site, something the entire team looks forward to, CE conferences at OCSAC! Dr. Kinney's pleasure in helping owners find solutions for their pets' problems is evident when you watch her work. She loves solving problems, enhancing comfort and quality of life for our animal companions, and she especially loves puppy kisses!
Active in the community, Dr. Kinney spent over ten years as a Board of Trustee Member for the Humane Society of Sedona, and two years as the medical director. She and/or the clinic has generously sponsored numerous youth sports teams, charities, and various cultural organizations in our city. Her hobbies include swimming, yoga, hiking, good food and wine, and doing anything fun outside with her husband Marc, their two boys and their dogs. Once in a while on a day off she indulges in an afternoon nap—working more than full-time, running a practice and raising children is exhausting! She credits her husband, Marc, whom she nick-named Superdad, with allowing her to achieve all of her goals by being an amazing and dedicated partner, father, and full-time practice manager. Additionally, Dr. Kinney, and/or the clinic, has been voted best veterinarian in Sedona for more than a decade, and she and/or her team and family have been featured in numerous local publications. Dr. Kinney's warmth, competence, positivity and reassuring demeanor are her trademarks!


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Lichtblick Film- und Fernsehproduktion GmbH ist eine deutsche Fernseh- und Filmproduktionsgesellschaft mit Sitz in Köln. Die Gesellschaft wurde 1991 von Joachim Ortmanns und Carl-Ludwig Rettinger gegründet. Ihnen obliegt auch die Geschäftsführung. Das Unternehmen produziert Dokumentarfilme, Doku-Serien und Spielfilme für Kino und Fernsehen. Seit Frühjahr 2014 arbeitet Lino Rettinger als Filmproduzent bei Lichtblick. Zusammen mit Produzent Martin Heisler wurde 2008 die Lichtblick Media GmbH in Berlin gegründet. Er ist alleiniger Gesellschafter und Geschäftsführer derselben.

Produktionen

Dokumentarfilme und Dokumentationen

 The Final Kick (1995)
 The Big Pink (1996)
 Der weiße Wal (2001)
 Moro No Brasil (2002)
 Mein Vater, seine Familie und Ich (2004)
 Im Angesicht des Todes (2004)
 Massaker (2004)
 Der Flamenco Clan (2004)
 Blutiger Sonntag (2006)
 Unter kaiserlicher Flagge / Teil 1: Die Karawane der Matrosen, Teil 2: Hetzjagd vor Kap Horn, (2006)
 Farbe des Herzens (2007)
 QI – Auf den Spuren Chinesischer Heilkunst (2008)
 Schlag. Fertig (2009)
 I Shot my Love (2010)
 Wiederkehr – My Reincarnation (2010)
 David wants to fly (2010)
 Weißes Blut (2011)
 The Substance - Albert Hoffman´s LSD (2001)
 Die Aupair-Omas (2012)
 Der Letzte Fang (2012)
 Vergiss mein nicht (2012)
 Die Hüter der Tundra (2013)
 Die schöne Krista (2013)
 Die Böhms – Architektur einer Familie (2014)
 Besessen von Dschinn
 Generation Beat Club (2015)

Dokuserien

 Abnehmen in Essen (2000)
 Frauen am Ruder (2002)
 Die Hundeschule (2003)
 Samba für Singles (2004)
 Eisfieber (2004)
 Wiedersehen macht Freude (2005)
 Zwischen Himmel und Erde (2005)
 Delphinkinder  (2005)
 Die Bräuteschule 1958 (2007)
 Gartenträume (2011)

Spielfilme

 Große Diebe, Kleine Diebe (1997)
 Ende der Geduld (1998)
 Die Frau, die an Dr. Fabian zweifelte (2001)
 Göttliche Intervention (2002)
 Weiter als der Mond (2003)
 Allein (2004)
 Cattolica (2004)
 Ein perfekter Freund (2006)
 Zweier Ohne (2008)
 Was du nicht siehst (2009)

Weblinks
 Internetpräsenz
 http://www.lichtblick-media.com/
 http://www.german-films.de/filmarchive
 http://www.german-documentaries.de/

Filmgesellschaft (Deutschland)
Medienunternehmen (Köln)
Medien (Köln)
Gegründet 1991

redpajama_set_name: RedPajamaWikipedia


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El Lissitzky. The Jewish Period (ENG)
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Unquestionably one of Russian modernism's best-known artists, El Lissitzky created artworks — in a staggering variety of media — that have entranced collectors and inspired other artists for decades. The subject of numerous monographs and exhibitions, his mature abstract paintings, drawings, photographs, and graphic work can be found in abundance in public collections worldwide. In this book, however, Alexander Kantsedikas, one of the world's leading experts on the artist, offers the first extended look at his earlier work, which was more or less exclusively devoted to Jewish subjects, reflecting his religious education and family's heritage. While a handful of these works are well known and widely published, this phase of his work will be far less familiar even to an audience well versed in El Lissitzky's oeuvre. Featuring more than five hundred works, lavishly reproduced in color and black and white, the book tracks his evolution from an expressionist style to one that is increasingly more abstract and nonobjective. It also includes rare photographic material of the artist's family, as well as little-known correspondence from his father and details about his relationship with his first wife, who has heretofore been entirely obscured in the artist's biography.
ISBN:1-910787-96-0
Праздничное оформление Петрограда-Ленингр...
Невский лед. Альбом
Пионеры супрематизма. Проект "Вербовка-10...
Архитектура советского модернизма.Мемориа...
100 Автопортретов
160 работ Анатолия Зверева
Театр одного художника. Анатолий Зверев. ...
Анатолий Зверев рисует сказки Андерсена
Метаморфозы или Золотой осел в иллюстраци...
Гоголиана Анатлия Зверева

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  Identification of Early Warning Indicators of Environmental Stress in the ACE Basin (South Carolina) by Using Gene Expression Profiles From Oysters, Crassostrea virginica|

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      Identification of Early Warning Indicators of Environmental Stress in the ACE Basin (South Carolina) by Using Gene Expression Profiles From Oysters, Crassostrea virginica

    EPA Grant Number: U916185

    Title: Identification of Early Warning Indicators of Environmental Stress in the ACE Basin (South Carolina) by Using Gene Expression Profiles From Oysters, Crassostrea virginica

    Investigators:
     Jenny, Matthew J.

    Institution:

      University of South Carolina at Columbia

    	EPA Project Officer:

           Boddie, Georgette

      Project Period:
      January 1, 2003 through
        January 1, 2006

        Project Amount:

          $124,000

      RFA:
      STAR Graduate Fellowships (2003)

          Recipients Lists

      Research Category:

          Academic Fellowships
          ,
          Biology/Life Sciences
          ,
          Fellowship - Biochemistry, Molecular Biology, Cell Biology, Development Biology, and Genetics

Objective:

The objective of this research project is to
  test the hypothesis that the physiological status of oysters is reflected in
  specific patterns
  of gene expression, which manifest via the interplay of internal processes
in organisms and external environmental stressors.

Approach:

Long-term chronic exposures to metals and organic
  pollutants from point and nonpoint sources (i.e., aerial deposition, boating
  activities) threaten
  estuarine ecosystems, including the ACE Basin, South Carolina. Crassostrea
  virginica, a common species found along the Gulf of Mexico and Atlantic seaboard,
  is an important indicator species of estuarine health, and a potentially valuable
  model for evaluating the relationship between ecosystems and human activities.
  "Transcript profiling" will be used to assess and compare the expression of
  approximately
  2,000 genes, including a family of metallothionein isoforms, in oysters from
  sites located primarily in the ACE Basin and a small number of highly contaminated
  sites in Charleston Harbor (Charleston, SC). In addition to the gene expression
  profiles, additional indicators of cell damage (glutathione, lipid peroxidation,
  lysosomal destabilization), tissue metals analysis, and environmental parameters
  (water and sediment quality) will be assessed. Artificial neural network techniques
  (ANN) will be used to analyze this multiparametric dataset. With the ability
  to store and utilize experience-based knowledge, ANNs can extract "signal"
  from "noise," making
  them ideally suited for large-scale ecological monitoring. The functional genomics
  approach will validate and expand traditional ecological models by incorporating
  gene expression patterns as part of the assessment strategy. Gene microarrays
  are sensitive, rapid-screening techniques capable of advancing current environmental
  assessment tools. The success of future conservation and management practices
  relies on a greater understanding of the effects of environmental pressures
  on organismal health. Gene expression profiles will be used to identify potential
  early warning indicators of long-term chronic stress.

Supplemental Keywords:

      fellowship, environmental stress, ACE Basin, gene expression profiles, Crassostrea virginica, metals, organic pollutants, estuarine ecosystems, South Carolina, SC.

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Last updated on Thursday, February 26, 2004

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JISHOU, HUNAN — YuTu (玉兔), China's first lunar rover, is experiencing some mechanical problems as it enters its second night time period on the Moon, worrying earthbound observers. Night comes to the Moon every two weeks, and temperatures drop below -180°C (-290°F). YuTu is supposed to pull in its antenna and camera, fold up its solar panels and hunker down, keeping itself warm with its radioisotope power source. Apparently, that process didn't quite happen, and Chinese space scientists are concerned the little rabbit may not wake up again. They are reportedly scrambling for some way to remotely repair the malfunction. The lunar lander, Chang'E 3, has also gone into hibernation, but it seems to be OK. The robotic duo landed last month and quickly sent back images of the landing site in Sinus Iridum, to the delight of the Chinese and space fans worldwide. YuTu, which is named after the mythical rabbit who lives on the Moon with the goddess Chang'E, has traveled 100 meters (about 100 yards) so far. Emily Lakdawalla has a more detailed report at the Planetary Society website. Universe Today has several high-res photos, as well. This one was Chang'E's Christmas gift to Earth.


text:
E&S Home > Vol. 25, Iss. 4 > Art. 43 > Abstract Open Access Publishing
Transboundary fisheries, climate change, and the ecosystem approach: taking stock of the international law and policy seascape
Cecilia Engler, Schulich School of Law, Dalhousie University
DOI: http://dx.doi.org/10.5751/ES-11988-250443
Full Text: HTML
The ecosystem approach to fisheries management is a conceptual and practical framework consistent with, and supportive of, climate change adaptation at the national and regional level. Implementing an ecosystem approach can contribute to climate change adaptation by improving ecosystem resilience and reducing vulnerability to climate change, by providing planning strategies and tools to monitor and assess the impacts of climate change on fisheries, and by relying on precautionary, flexible, and adaptive approaches that account for the uncertainties, surprises, unpredictability, and dynamism of ecosystems in a changing climate.
In this article, I provide an overview of some key considerations framing the mandate and capacity of regional fisheries management organizations and arrangements to implement ecosystem approaches in the context of climate change. The article first addresses the extent to which international law of the sea, and in particular the 1995 United Nations Fish Stock Agreement, endorses and implements an ecosystem approach to fisheries for the management of straddling and highly migratory stocks. It then addresses the barriers to more effective implementation of an integrated and adaptive ecosystem approach to fisheries in transboundary settings, including the decentralized and consensus-based nature of international law, stationary visions of ecosystems, and principles of certainty and stability. This analysis is then expanded to focus on specific challenges of adapting to climate-induced changes to transboundary stocks distribution and abundance. I address preparing and planning for climate change, responsive decision-making procedures, regulation of new fisheries, jurisdictional challenges, enhancing marine resilience, and revisiting allocation agreements, highlighting legal provisions and policy developments that may support or enhance the adaptive capacity of transboundary fisheries arrangements.
I conclude that, despite some supportive legal provisions and practices, structural, legal, and political barriers severely hinder the pace and the scope of required governance and management responses to climate-induced changes to transboundary stocks.
adaptive management; climate change; ecosystem approach to fisheries; integrated management; law of the sea; ocean acidity; regional fisheries management organizations or arrangements
Copyright © 2020 by the author(s). Published here under license by The Resilience Alliance. This article is under a Creative Commons Attribution-NonCommercial 4.0 International License. You may share and adapt the work for noncommercial purposes provided the original author and source are credited, you indicate whether any changes were made, and you include a link to the license.
Ecology and Society. ISSN: 1708-3087


text:
Q: docker selenium remote server how to block or whitelist ips I set up a docker selenium server for browser testing using docker selenium
I run it with:
docker run -d -p 4444:4444 -e CHROMEDRIVER_WHITELISTED_IPS='123.123.123.123' -v /dev/shm:/dev/shm selenium/standalone-chrome

however, since i cannot bind to 127.0.0.1 , the docker server can be used from external ips as well (not only 123.123.123.123), the whitelist parameter did not werk.
What is a good way to solve this

A: I'm not entirely sure of what you are trying to do, but I needed to set the whitelisted-ips parameter to allow all IPs for use with the wdio-devtools-service. In order to do this one needs to pass the whitelisted-ips parameter to chromedriver within the docker container. To do that I started it like this to set the whitelisted-ips to an empty value, which then allows all external IPs:
docker run -d -p 4444:4444 -p 9222:9222 -e JAVA_OPTS="-Dwebdriver.chrome.whitelistedIps=" -v /dev/shm:/dev/shm selenium/standalone-chrome

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Listen to our free podcasts and learn or improve your French on the go, where and when it suits you.
Take the next step and sign up for a course on the Coffee Break Academy, accessing video materials, lesson notes and bonus audio content.
Improve your vocabulary, build your language skills and keep up with the Coffee Break French team on social media.
Coffee Break French is currently available in four levels, represented by each "season". Each season features 40 lessons.
Learn to use French confidently when travelling, ordering food and drinks, making friends and shopping in a French-speaking country.
Build your knowledge from Season 1, learn to use French grammar to "say what you want to say" and become more confident.
Extend your range of language by building your knowledge of more complex grammar through authentic and engaging materials.
Expand your vocabulary and your understanding of complex grammar through advanced materials.
Each series is slightly different in the way in which it is presented and in the materials provided. Scroll down for more information and to find out about our En Route course.
Each Season of Coffee Break French offers a huge amount of free content available as audio podcasts. You can access these on our website, on Apple Podcasts, Google Podcasts and Spotify and each lesson lasts around 15-20 minutes - the perfect Coffee Break length!
If you'd like to take your learning further and make faster progress, we offer a full online course for each Season. Resources include bonus audio materials, video episodes and lesson notes. See below for further details for each Season.
Or search for "Coffee Break French" on your favourite podcast app or on Spotify.
Find out more on the Coffee Break Academy.
The £GBP price quoted above includes VAT for the UK. VAT is added automatically at the local rate for customers purchasing within the EU. Customers from elsewhere in the world will not pay VAT. Please note also that we offer bundles of multiple seasons on the Coffee Break Academy.
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Join teacher Mark and learner Anna for 40 lessons of basic French. You'll start by learning to introduce yourself and master greetings, and then work through a range of topics which are useful to anyone travelling in a French-speaking area. You'll not simply be repeating phrases: instead you'll learn how the language works and you'll understand what you're saying.
Topics include greetings, introducing yourself, talking about your family, your likes and dislikes and your job. You'll also learn to use French in a variety of transactional situations, including ordering food and drinks, using public transport, asking for directions, going shopping and much more.
The premium version of Season 1 includes bonus materials to help you make faster progress with your learning. In addition to the main audio lesson, you'll also have access to a video version of this lesson where you'll see the words on the screen of your device. There's also a bonus audio episode and comprehensive lesson notes to help you get to grips with the language taught. This course is available on the Coffee Break Academy.
In Season 2 you'll build your understanding of French, moving on from a beginner's level to an intermediate level. You'll learn about how the language works and to "say what you want to say", manipulating the language in a variety of tenses. You'll join learner Anna and teacher Mark, and cover a range of topics, building a solid understanding of French grammar through the lessons of Season 2.
Season 2 puts French grammar into a range of contexts. For example you'll learn to use the present tense to make arrangements and talk about your daily routine. You'll also learn to use past tenses and how to describe things using adjectives. You'll build on the transactional areas of vocabulary covered in Season 1 and apply your new-found knowledge of the language to these areas.
The premium version of Season 2 are similar to those of Season 1 and these bonus materials will help you make faster progress with your learning. In addition to the main audio lesson, you'll also have access to a video version of this lesson where you'll see the words on the screen of your device. There's also a bonus audio episode and comprehensive lesson notes to help you get to grips with the language taught. This course is available on the Coffee Break Academy.
Season 3 will help you take your French a stage further, to an upper intermediate level. You'll be following the story of three students of the language who are taking a French course in the city of Nice on the French Riviera. Through the journal entries of Katy, Alf and Veronica, you'll be exposed to a range of complex structures and interesting vocabulary.
Since Season 3 follows a story, we'll not be dealing with specific topics as such in this course, but you'll cover a whole range of vocabulary areas as you read about the adventures of our three characters. Learning a language is about building your range of language structures and by following these stories you'll do just that. In terms of grammar, we'll cover the future and conditional, help you build your confidence with past tenses, and you'll also learn about a variety of grammar points.
The online course for Season 3 includes additional materials to help you make faster progress with the language. In addition to the main audio episode for each lesson, you'll get access to a specially extended audio episode which we call the Language Study episode. In this episode we'll explain in detail the entire text for each lesson, and you'll be tested with some translations. You'll also get access to the lesson notes which provide further examples of the language covered in each lesson.
Season 4 is aimed at advanced students of French. You'll be following the story of Sylvie, who is working at a Parisian publishing company, and Matthieu, a young accountant, also working in the city. Over the course of the 40 lessons of the series, you'll develop a solid understanding of complex grammar and idiomatic expressions. The course is presented by teacher Mark and native speaker Pierre-Benoît.
The course includes two audio episodes per lesson. In the first of these, Mark and Pierre-Benoît pick out some key phrases and grammar points included in the text for the lesson and discuss these, providing further examples. In the second audio episode, the Language Study episode, you'll go through the text in its entirety, and all complex grammar points will be explained. The online course also features the full transcript of both episodes, along with vocabulary and explanations.
For intermediate/advanced learners we also offer En Route avec Coffee Break French. In this ten-lesson series you'll join Mark and the Coffee Break team "en route" in the south of France and you'll listen to interviews with people who live or work in the area. These conversations feature authentic French, with a whole range of different accents and speeds of delivery, so it's the perfect way to improve your listening comprehension.
Each episode of En Route centres around a different topic, from local tourist attractions to culinary specialities. You'll learn about what it's like to live on a linguistic border between France and Italy, you'll discover the local area and its history and culture, and you'll be filled with the desire to visit this area for yourself to try out your own French!
The online course for En Route offers additional materials in the form of extended audio episodes and bonus interviews, all of which have full transcripts provided with notes and explanations about the language used where necessary. There's also exclusive video content which will help you get to know the area that bit better – and practise your French at the same time.
We publish regular lessons both in the Coffee Break French podcast feed and on our YouTube channel. Here's a selection of our most recent lessons.
We're delighted to announce that the Coffee Break French Masterclass will open its doors once again on 1st September 2018, ready to begin the new 6-month course which runs until 28 February 2019. Registration will begin on 1st August 2018.
Who is behind Coffee Break French?
Coffee Break French is a production of the Radio Lingua Network and we produce all Coffee Break Languages courses, along with One Minute Languages and High Five Languages for younger learners. The Radio Lingua team is made up of experienced teachers and native speakers and we're based in Glasgow, Scotland. To find out more about the team, visit our Meet The Team section of the website.
What's the difference between the free podcasts and paid course?
lesson notes for Seasons 1-3 and transcripts for Season 4 and En Route.
If you're serious about learning French we would suggest that you consider the online course to help you make faster progress with the lessons and build a deeper understanding of the language.
*Please note that the video lessons currently feature only in Season 1 and 2 courses. We plan to add video versions of the Season 3 and 4 lessons soon.
Our audio podcasts are free and you can access them here on the website, on your favourite podcast app, or on Spotify. We offer a paid online course which provides additional materials. The cost for one season is £96.00 GBP including VAT, or $104.00 USD excluding VAT. Please see above for further information on pricing.
Is there an app version of Coffee Break French?
We do not currently have an app version of Coffee Break French. In the past we have had problems with a group of developers who have stolen our content and published it within paid-for apps. These apps are not published by Coffee Break Languages. We've written extensively about this situation on our website. Please do not purchase our content through these apps. The only way to access Coffee Break French lesson notes, bonus audio and video versions is through the Coffee Break Academy.
The Coffee Break French Masterclass is a special 6-month course which normally runs twice a year. This is a guided course in which intermediate learners can build their confidence and understanding of grammar in a structured way. We provide individual feedback on homework activities, and the course features six modules covering a range of topics. To find out when the next Masterclass is running, click here.
Do you offer one-on-one lessons via Skype?
We do not currently offer one-on-one Skype lessons. If this is something which interests you, we would suggest that you sign up with our partner italki where you can access individual teachers and native speakers to practise your French. Visit italki.com to get a voucher for $10 USD in italki Credits when you purchase your first lesson.
Sign up for our monthly newsletter to keep up to date with Coffee Break French. In each edition we'll share the latest news and our roundup of cultural and language links from around the web, and we'll deliver this straight to your inbox every month.


These were just something I threw together for a 4th of July party, aren't they cute and pretty? I'm not gonna lie, I'm not one for fancy food that takes a lot of time to assemble. But these were worth the extra bit of effort.
Feel free to mix up the fruit choices, but I encourage you to keep the feta! The combo of the feta and basil with the balsamic glaze is OH SO GOOD with the sweetness of the fruit. And I can guarantee you people will be impressed if you bring this colorful dish to any gathering.
Cut the watermelon and feta cheese into cubes. I prefer the watermelon cubes to be a bit larger than the feta, I think it looks prettier when stacked.
Assemble the skewers: basil leaf, blueberry, feta cheese, then watermelon. This is why you need the longer toothpicks! Pierce the pieces gently so they don't fall apart -- especially the cheese!
Place the balsamic vinegar and honey in a small saucepan. Bring to a boil, then reduce to a simmer for about 10-15 minutes. Liquid should reduce by about half.
Let sit for about 10 minutes so it will cool and thicken.
Drizzle on top of skewers or place in a small bowl for people to drizzle themselves.


Why do you need a web site made in ELRO? Simply put, because it will improve your image, attract visitors and therefore increase your sales.
Whether you are selling products or services, promoting your ideas, popularizing your beliefs or building a following, ELRO will create a site that is custom-built for your specific market needs.
A web site designed by ELRO will make your business stand out head and shoulders above your competition. We parallel the technology of the site to your business model, industry and specific needs. We learn all about the business you are in - we take the time to get to know our client and we use our passion, inspiration, knowledge and experiences in the creation of every site we do.
How do you accurately represent a security company that does not trade on fear? How do you set it apart from the competition? ELRO rose to the challenge with a unique approach, combining bold use of color, daring outlines and open and honest information presentation.


The Old North Church & Historic Site is interviewing for educators.
As an educator at Old North you will be part of a close-knit and enthusiastic team committed to providing visitors with an excellent and enjoyable experience.
Leading specialty tours and other in-depth educational experiences.
Additional opportunities to develop special programming and to write for our history and news blogs.
Please submit a resume and cover letter to: jobs@oldnorth.com. Please reference the position for which you are applying in the subject line of your email. Interviews are ongoing.


In an industry where turnover is high, which can result in increased recruiting and training costs, offering competitive pay and benefits is not enough.
Employees most often want to be recognized and shown appreciation for doing a great job. Because each employee can have a different preference regarding how he or she is recognized and shown appreciation, it is essential to determine what motivates each of your employees. Doing so will help you provide the recognition we all want and retain your valuable employees. The following are a few strategies that can help.
Manage everyone individually. Everyone is different, but some are so different that they may require a personalized management style. Knowing your employees on an individual basis is the only way to know how to manage them effectively. Recognize their strengths, and challenge employees with specific goals they can achieve.
Support new ideas. When employees come to you with an idea or a solution to a problem they believe is for the betterment of the company, it is a sign they care. Supporting new ideas and giving an individual the chance to "run with it" is motivating, whether or not it works out in the end.
Empower each individual. Every single individual contributes to the bottom line. Empowering your employees to excel in their role, no matter how large or small, creates a sense of ownership that will lead to meeting and exceeding expectations.
Listen. This is probably the easiest thing you can do for an employee; however, it can also be the most difficult. Carving out some time each day to listen to anything from concerns to ideas will not only make your employees happy, it will also provide you with much-needed insight into your business from the people who help keep it running.
Be clear with expectations. Do not leave too much to be determined. Set clear expectations so you can plan for specific results.
Make things interesting. Shaking things up every now and then is a good way to break up the day-to-day routine of the work schedule. Bonuses, vacation days, office parties and holiday parties are many of the tools employers can use to reward employees for a job well done and motivate them to produce similarly stunning results in the future while also keeping morale high.
Employee awards. I believe that companies with a culture that supports employee recognition have more engaged employees and better employee retention.
Education/training reimbursement plans. Offer training courses to encourage your employees to reach their full potential while also ensuring your company structure flows smoothly.
Education reimbursement plans for courses directly related to your employees' jobs keep your company compliant and also keep employees educated during changing times, especially in our industry. This also creates a stronger commitment from employees when an employer takes interest in their particular skillset.
So while providing balance, welcoming new methods and cultivating a positive work environment, give them a reason to come to work every day… an employee who enjoys coming to work every day is a good investment in your organization!
Cheryl Boyd is the Vice President of Administration for Advanced Integrated Technologies (AIT) & Surge Force where she is responsible for Human Resources, Accounting, Purchasing and the West Coast Staffing Division. She has been employed with AIT for 5 ½ years.


text: Q: Outlier detection- univariate vs multivariate One gets different results upon using a univariate approach (boxplot) vs using a multivariate approach (Cook's distance). Which is more advisable ? Univariate boxplots are pretty easy to use but one can end up misjudging observations.


Parents of a young teen diagnosed with an Autism Spectrum Disorder have many things to consider when choosing a secondary school for their son/daughter to attend. Parents and the teenager themselves need to consider the pathway options available. Further assessments are likely to be undertaken nearing the end of the primary school years. These assessment outcomes along with school reports will help you to plan for the secondary years.
These are your local neighbourhood schools that could be either Government, Religious or Independent/Private Schools. Distance and school population will be further considerations as schools cater for students entering from a number of primary schools.
Are those schools that cater for students with additional learning needs and these schools could be disability specific.
Remember that the decision you make can be changed at any time. While secondary school is another six years of school, the decision you make can change over the course of that time. When looking for a secondary school parents and the young teen may need to consider many things. Check out our Transition Checklist for Secondary School, Transition Checklist for Special School and SSG Meeting Preparation resources for more help.
There is much to think about when planning the next educational transition to secondary school. Talk with your child's primary school as they will have insights into what your child needs in regards to educational, environmental, communication and social supports in regards to future educational pathways.


text:
With more than two hundred titles in the portfolio, Pragmatic Play has something for everyone. Their slot machines offer smooth graphics and easy-to-understand gameplay, making them a great choice for new and experienced players. The company also puts a lot of effort into active promotion of their products. Aside from offering a wide variety of slot games, Pragmatic also offers tournaments and other promotions to help players win prizes.
The company also offers many free games. One of the free slots you can play is a game called Magician's Secret. It uses a simple strategy to win. When a player makes a winning combination of symbols, it will trigger a bonus. In this way, the player can win a jackpot.
Multi-line slot games are another type of slot. These types of slots have more than one payline and feature a variety of symbols. For example, a game with three symbols on a single bar could award a prize worth up to seven million dollars. The game also features a wide variety of other bonus features, including free spins.
When playing online slot games, it's essential to choose a site that offers the type of game you enjoy. Some sites feature a variety of games, including progressive jackpots, and they also provide tips and tricks for winning. When choosing a site to play, make sure to test the game thoroughly before committing to it.
Another great option for a free slot game is the Pragmatic Play slot Great Rhino. This five-reel, 20-payline slot has an exciting savannah theme and offers colorful visuals. The high resolution graphics provide a high quality experience. Moreover, players can win big prizes without paying a dime.
If you're unsure whether you'd like to try a slot, you can always try a free demo. The providers of the free slot games offer these for their users. While these demos are not the only way to decide whether a slot is for you, they can be a good start for new players.
High volatility slots offer higher rewards but also high risk. Players should only participate in high-volatility slot games if they have a large bankroll and plenty of free time. High-volatility slots can be dangerous to your finances, as the large payouts can fool you into playing more than you should. If you're looking for a game with a high volatility rating, Pragmatic Play has several options for you.
Important Considerations When Choosing an Online Casino