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In the present work we studied the effect of temperature and molarity on microstructural and optical properties of Ag3O4 thin films deposited by spray pyrolysis. Transparent conductive thin films of silver oxide (Ag3O4) were prepared by using an aqueous solution of silver nitrate (AgNO3) and sprayed onto heated soda glass substrate at 350 °C and annealed at 550°C. X-ray diffraction showed that the films have a monoclinic structure with a preferential orientation along the (031) direction. A visible shift of the main peak as a function of temperature and solution molarity is observed. The lattice parameters a, b and c are estimated to be 3.68, 9.30 and 5.20Ǻ respectively. Scanning Electron Microscopy (SEM) analysis shows that all films are nanostructured and homogeneous with dense surfaces. Transmittance and reflectance measurements are performed in the spectral range 200-1600 nm and yielded a band gap energy (Eg) varying in the range 3.07-3.25 eV. Refractive index was studied in terms of Moss, Ravindra and Herve–Vandamme models. The optical constants such as the oscillator energy (E0), static refractive index (n0), dispersion energy (Ed) and dielectric parameters (εr ) of the films were derived from the analysis and discussed.

K’gari (Fraser Island) offers a rare opportunity for people to observe and encounter wild dingoes. Occasionally, however, such encounters can entail dingoes acting in a threatening or aggressive manner towards people, resulting in human injury and, in one tragic case, death. A suite of approaches aimed at minimising the risk to human safety posed by dingoes have been implemented on the island, including fencing, island-wide warning signage, and regulations against feeding. Despite such measures, negative encounters continue, and in cases where dingoes are deemed to pose an unacceptable risk, they are usually destroyed. In searching for non-lethal management alternatives, attempts have been made to modify undesirable dingo behaviour through aversive conditioning, but results to date have either been mixed or largely disappointing. Here we review a wide array of research that has utilised aversive stimuli in an effort to modify and manage the behaviour of wild animals, with a particular focus on related predators such as coyotes and wolves. We identified eight major categories of experimental research: conditioned taste aversion/avoidance (CTA), electric fencing, fladry, chemical repellents, fear-evoking stimuli, physical repellents, aversive collars/devices and hard release procedures. We then outline each of these categories in more detail, complete with pertinent examples of successes and failures as well as advantages and disadvantages. We conclude that some approaches offer promise within three main areas of incident mitigation experimentation: dingo exclusion (e.g. electric fencing), personal protection (mild chemical irritant sprays, sturdy umbrellas) and remedial aversive conditioning (e.g. shock collars). Other approaches, such as CTA and sublethal projectiles are not recommended. Like any approach, aversive conditioning is not a panacea, but it does offer promise in filling gaps in current management and as an alternative to lethal control.

Occasionally, interactions between dingoes (Canis dingo) and people on Fraser Island result in serious injury, and, in one case, death. The risk to human safety from such interactions may be mitigated if people could carry a suitably defensive repellent, similar in principle to bear (Ursus spp.) repellent spray advocated in North America. In the first step towards searching for suitable stimuli that might be used as repellents with dingoes, we observed the responses of nine dingoes to three stimuli during interactions with a researcher on Fraser Island. Two treatment stimuli were assumed to be potentially aversive (an air horn blast and a water jet from a motorised water pistol), and one was considered unlikely to be aversive and therefore suitable as a control (a whistle being blown). Responses to the stimuli varied. All nine dingoes were initially presented with the whistle; however, only one adult male responded as if the whistle was aversive. Seven of the nine dingoes were later presented with a whistle and treatment stimuli together. None of the seven dingoes were repelled during any air horn treatment trials; however, six of seven dingoes (all juveniles) were repelled by the water pistol stimulus. Although a water pistol was effective at repelling young dingoes on many occasions, responses between individuals were inconsistent. Results from this pilot study suggest that a water pistol stimulus may offer some protection as a repellent to close approaches by young dingoes, particularly if enhanced with a mild irritant.

The road-effect zone is a concept developed to describe the impact of influences such as noise, vibration, light and dust associated with roads and traffic on the surrounding area. Although many aspects associated with the road-effect zone have been investigated, the influence of dust remains poorly understood. Gap Creek Road, a minor road traversing forest near Brisbane, Australia, was upgraded in 2010 by sealing and realignment. The present study compares pre- and post-construction dust levels within the forest, and the diversity and abundance of ground-dwelling mammals near (2–5 m) and far (80–100 m) from the road. Prior to the upgrade, dust levels were very high with deposition rates equivalent to a major daily dust storm. The key influence of the upgrade was the almost complete elimination of this dust production; hence, we predicted that species richness and abundance of small mammals near the road would increase significantly after the upgrade. Pre-upgrade surveys confirmed that the forest supported a diverse and abundant community of ground-dwelling mammal species with eight species detected, including in highly dust-affected sites near the road. Following the upgrade, there was little change in the abundance of species, though some were significantly more abundant away from the road. These results suggest that, in certain environments, dust may have far less impact on ground-dwelling mammals than expected.

It has been shown early that curved plots for the conductivity of polycrystalline diselenide molybdenum were systematically obtained whatever the technique used for the obtention of the layers. In the general case of polycrystalline semiconductors these deviations from the simple thermoionic emission across the grain boundaries have been recently attributed to potential fluctuations at the grain boundaries. Here a good agreement between the experimental results and this new theory is obtained. The result deduced from theoretical propositions is conforted by the scanning electron micrographs of the layers and other preceeding experimental studies. In the light of the discussion of the MoSe2layers, a quality factor Q is proposed for photovoltaic thin films. This estimation shows that the films obtained by solid state reaction and substitution are the best. Mo and Te thin films are sequentially deposited. Then an annealing under Se and Te pressure at 770 K for 24 h gives crystallized and stoichiometric MoSe2thin films. These films have the higher quality factor among the films studied here (Q = 0.75). This is in close agreement with the good electrical and optical properties of these layers.

Une technologie d'obtention de couches minces texturées de MoSe2a été mise au point. Ces couches sont obtenues à partir de couches de MoTe2déposées par pulvérisation diode continue, puis traitées thermiquement (recuit 24 h à 840 K) en présence de vapeur de Te et de Se, L'évolution des propriétés des couches, en fonction du rapport atomique Se/Te présent lors du recuit, est étudiée par spectroscopie de photoélectrons (XPS), diffraction de rayons X et microscopie à balayage.

The conductivity of WSe2, MoS2, WS2thin films, obtained by solid state reaction between the metal and the chalcogen sequentially deposited, is controlled by grain boundary scattering mechanisms. A mild annealing treatment at 373 K for 1/2 h to 6 h under iodine atmosphere improves the conductivity of the films. In the case of WSe2, which gives the better results, the room temperature conductivity can be multiplied by 25. if the conductivity is improved, its dependence with the temperature demonstrates that the conductivity process is still controlled by grain boundary model. Barrier height fluctuations at the grain boundary are introduced to have experimental and theoretical data fit together. After iodine treatment the mean barrier height has decreased and the homogeneity of the films is improved. These improvements are very promising for photovoltaic since it appears that iodine passivates defects at the grain boundaries.

AbstractObjectivesThis study compares the prevalence and perinatal mortality of congenital heart defects on La Réunion with European (EUROCAT) standards.Methods and resultsData were extracted from a EUROCAT-affiliated congenital malformations registry, covering 88,025 births during the period 2002–2007, on the whole island territory. A total of 512 congenital heart defects were registered, including 424 live births, 18 foetal deaths from 16 weeks of gestation, and 70 terminations of pregnancy. The total prevalence of congenital heart defects was 5.8 per 1000 births and live birth prevalence was 4.8 per 1000. The total prevalence of non-chromosomal congenital heart defects was 5.1 per 1000 births, of which 3% were perinatal deaths, 33.3% prenatally diagnosed, and 11.6% termination of pregnancy. Severe non-chromosomal congenital heart defects – excluding ventricular septal defects, atrial septal defects, and pulmonary valve stenosis – occurred in 2.1 per 1000 births, of which 10.3% were perinatal deaths, 59.1% prenatally diagnosed, and 24.3% termination of pregnancy. Of the severe congenital heart defects, the rates of single ventricle (0.20‰), Ebstein anomaly (0.11‰), common arterial trunk (0.25‰), and atrioventricular septal defect (0.62‰) exceeded averages found in Europe, although coarctation of the aorta was infrequent. Conversely, rates of ventricular septal defects, atrial septal defects, and pulmonary valve stenosis were inferior to European standards. Slightly less than half of the congenital heart defects of chromosomal origin were associated with Down syndrome.ConclusionIn La Réunion, the total prevalence of congenital heart defects is far inferior to that found in Europe. The difference can be attributable to lower prevalences of mild congenital heart defects.

The synthesis of poly(m-aminophenyl propionic acid) (PAPPA) was carried out by polymerization in different aqueous media, from the respective monomer, using ammonium persulfate as oxidizing agent. The copolymer of aniline and m-aminophenyl propionic acid was also synthesized. The polymers were characterized by FTIR, UV-vis, X-ray electron spectroscopy, nuclear magnetic resonance spectroscopy, elemental analysis, thermal stability analysis (TGA), and electrical conductivity. PAPPA showed a high doping by HCl and H2SO4. If the composition of the comonomer acid decreases, the incorporation of copper ion and the electrical conductivity are increased. Thermal stability is favored by an increase of the content of aniline and copper ions. The polymeric structures have amine and imine groups. The last units are preferentially doped. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 706–715, 2003

2,2'-Dithienylimine was synthesized and electrochemically oxidized. The polymer was obtained on platinum or glass electrodes coated with tin oxide. The films were characterized with scanning electron microscopy, microprobes, and X-ray photoelectron spectroscopy. The coverage efficiency of the films was very high, but there were some morphological defects on the surfaces. Furthermore, there was some oxygen contamination not only on the surface but also in the bulk of the films. The nucleation and growth mechanisms responded to tridimensional instantaneous nucleation and bidimensional progressive nucleation contributions, which were consistent with the morphologies determined by scanning electron microscopy. The current–voltage characteristics exhibited a turn-on voltage of 5–6 V, which depended on the film thickness. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1614–1621, 2003

In this article, the new red-colored copolymer, referred to as C1–4poly-phenylene-vinylene- ether (C1–4PPV-ether) is built as a PPV polymer with some conjugated links (&bond;CH&dbond;CH&bond;) that are changed into ethylic-ether links (&bond; CH2&bond;O&bond;CH2&bond;) and whose modified phenyl ring is grafted, respectively, in two and five positions with methoxy and butoxy groups. The C1– 4PPV-ether is doped with protonic acid or iodine. The infrared absorption (IR), optical density, X-ray photoelectron spectroscopy (XPS), and electron spin resonance (ESR) show that there is a charge transfer complex formed between the copolymer and the doping species (iodine or acidic dopants). From IR, XPS, and ESR analysis, we deduced that the doping mechanism of the copolymer is, respectively, a protonation of the double links in PPV in the case of the protonic acid doping process and a grafting of the iodine to the ether links in the case of iodine-doping process. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1858–1866, 2002

The initiation of the electrochemical growth of polythiophene thin films was studied by X‐ray photoelectron spectroscopy (XPS), electron probe micro analysis (EPMA), and mainly by scanning electron microscopy (SEM). The films were deposited on SnO2‐coated glass in a classical three‐electrode cell. Depositions were done under pure argon atmosphere. Two electrolytes were tested, tetrabutyl ammonium hexafluorophosphate (Bu4NPF6) and tetramethylammonium hexafluorophosphate (Me4NPF6) in anhydrous acetonitrile. The effect of the electrolyte, and monomer and electrolyte concentration, on the film properties were visualized. These results are discussed with the help of the other characterization techniques. It is shown that for optimum concentration (0.05Mmonomer and 0.05Melectrolyte), two processes are active, one three‐dimensional (3D) and one two‐dimensional (2D). When the monomer concentration is increased, a third 3D contribution is presently active. When the electrolyte concentration increases, there is some electrolyte crystal precipitation on the synthesized polymer films. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1799–1809, 2002; DOI 10.1002/app.10291

Wide band gap β-ln2S3thin films have interesting properties to substitute CdS as the buffer layer in thin film solar cells. They have n-type conductivity and their optical band gap is about 2.8 eV. In this paper, β-ln2S3thin films deposited on smooth glass and on rough SnO2-coated glass substrates have been morphologically studied by X-ray photoelectron spectroscopy (XPS) and by atomic force microscopy (AFM). The results obtained show that on each substrate the films are continuous without any pinholes and cracks. Films deposited on glass cover homogenously the whole surface of the substrate. In the case of SnO2substrates, the material deposited preferentially fills the hollows of the rough surface inducing a decrease of its roughness value. It is shown that these morphological properties are very promising for buffer layer application.

In this work, we present the results obtained for the polymerisation in non-aqueous media of thiophenes derivatives; [2-Tenal-acetotienone] and [1,5-bis(2-Tenal)-1,4-pentadien-3-one], via electrochemical deposition on indium tin oxide (ITO) glass electrodes. The I–Vcurves and electroluminescent response was evaluated. It was studied that the film thickness affects the metal/polymer interface properties during the devices operation. The results indicate that diodes and electroluminescent response occurs at 2–3V though anomalous device behaviour can be found when the reverse biaswas applied.

β-In2S3 thin films have been prepared by the spray pyrolysis technique. X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) micrographs showed a good homogeneity of these layers. Microanalysis and XPS measurements have detected little oxygen in the films present in In2O3 form. Photoconductivity measurements were carried out within the range of wavelengths in the visible spectrum at different modulation frequencies f and bias voltages V ranging from 5 to 300 Hz and from 3 to 25 V, respectively. The band gap energy Eg, deduced from these spectra, has approximately the same value as that obtained from spectrophotometric transmission and reflection measurements (Eg = 2.05 eV).

Silver sulfide Ag2S thin films have been prepared on pyrex and on SnO2/pyrex substrates by the spray pyrolysis technique (Dlala et al., Europ. Phys. J. A 2, 13 (1998)) using silver acetate and thiourea as precursors. The depositions were carried out at 200 and 250 °C. The X-ray diffraction spectra show that a substrate temperature Ts = 250 °C with a concentration ratio x = [S]/[Ag] = 2 in the solution allows to obtain well crystallized thin films with a preferential orientation along (-103) direction. Microprobe analysis as well as X-ray photoelectron spectroscopy (XPS) show that a nearly stoichiometric composition is obtained under these conditions. Moreover, we noticed by the same technique the presence of oxygen and carbon components particularly on the surface, due to a contamination effect. Indeed, it can be seen after etching that the intensity peaks decrease strongly, which indicated the weak proportion of these elements in the bulk of the films.

Stable CdS thin films were prepared by radio frequency sputtering onto glass substrates from a CdS target (purity 4N). The as-grown films were thermally annealed under vacuum at 100 and 150 °C. The effect of the annealing temperatures on the structural and optical properties of the films was investigated. Grazing incidence X-ray diffraction (GIXD) studies show that the CdS films annealed at 150 °C were continuous and homogeneous as opposed to the as-deposited and the films annealed at 100 °C.

Polycarbazole has been synthesized by electrochemistry. The carbazole monomer source consists either in carbazole in solution in the electrolyte or in carbazole deposited in thin film form onto the working electrode. The two families of polymers have been studied by infrared absorption, X-ray diffraction, thermal gravimetric analysis, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy, electron spin resonance, and electrical conductivity measurements. It is shown that the polycarbazole films obtained with carbazole deposited in the thin film form exhibit a better polymerization efficiency and an electrical conductivity one order of magnitude higher. This result is in good accordance with a higher spin density and homogeneity. It is proposed that not only are some monomers activated during the evaporation but also that the physical contact between the working electrode and the continuous carbazole films induces the growth of homogenous highly polymerized polycarbazole films. In agreement with this suggestion, the SEM study shows that this type of polycarbazole thin films keep in memory the morphology of the SnO2 under layer. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 1561–1568, 2000