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Tin oxide was prepared by chemical methods and then doped with different weight ratios of vanadium 2wt% and 4wt%. The structural, morphological, and optical properties were studied. It was found that all the recorded films had a polycrystalline diffraction pattern and that the predominant reflection was (111) plane. The doping processes resulted in the improvement of crystalline structure and the disappearance of a number of secondary reflections and the direction of the film in a single crystalline pattern, thus reducing the values of energy gap and percentage transmittance. The morphological properties were studied by converting the three-dimensional images into graphic drawings to enable us to easily calculate surface parameters.

Highlights • The chemical spray was added to enhance the effect of turbulent agglomeration. • The chemical-turbulent agglomeration had better effects on fine particle agglomeration. • High removal efficiency was obtained by chemical-turbulent agglomeration. • The adhesion force between fine particles was strengthened after chemical spray. • The value of turbulent agglomeration kernel increased after chemical spray. Abstract Turbulent agglomeration is a simple and economical method to improve the agglomeration of fine particles from coal combustion, which is beneficial to the particle removal efficiency of conventional equipment. However, the agglomeration efficiency for fine particles is low by single turbulent agglomeration because of the weak adhesion forces between particles, which leads to plenty of ineffective collisions. In this study, a novel technique was presented to improve the effect of fine particles agglomeration in turbulent agglomeration by adding chemical spray. The influence of single turbulent agglomeration and chemical-turbulent agglomeration on fine particle concentrations, particle size distributions, ESP performance, particle removal efficiencies in different stages and total dust concentrations after ESP were investigated respectively. The results showed the chemical-turbulent agglomeration had better effects on the agglomeration and removal of fine particles than single turbulent agglomeration. After chemical-turbulent agglomeration, the PM 10 number concentration decreased about 34.1% than single turbulent agglomeration, and particle number concentration dropped at each stage under 10 µm, especially at 0.1 µm. Meanwhile, the application of chemical-turbulent agglomeration led to the number removal efficiency of PM 10 increasing from 82.6% to 89.9%, the mass removal efficiency increasing from 84.5% to 91.8%, and the total dust concentrations after ESP reducing about 638 mg·m−3 than single turbulent agglomeration, respectively. Furthermore, the enhancement mechanism of chemical-turbulent agglomeration was explored by analyzing adhesion forces between particles and calculating the turbulent agglomeration kernel. In this study, the capillary and solid-bridge forces between particles and the increasing value of K TS after chemical spray were considered as the main reasons for better effects of chemical-turbulent agglomeration. [ABSTRACT FROM AUTHOR]

Investigation on the management of thrips, Scirtothrips dorsalis Hood infesting green gram was carried out under field condition during 2017 at Pulse Research Station, Junagadh Agricultural University, Junagadh, India. For the management of thrips, different combinations of seed treatments viz., imidacloprid 30.5 SC @ 0.12%, clothianidin 50 WDG @ 0.20% and thiamethoxam 25 WG @ 0.01% and foliar application of insecticides profenophos 40% + cypermethrin 4% 44 EC @ 0.044%, spinosad 45 SC @ 0.0135% and flonicamid 50 WG @ 0.015% were evaluated against the pest. Based on pooled over periods, seed treatment of thiamethoxam 25 WG @ 0.10% and insecticidal spray of spinosad 45 SC @ 0.0135% was found most effective for the control of thrips. The highest (1066 kg /ha) seed yield was gained from the plots treated with thiamethoxam 25 WG @ 0.10% + spinosad 45 SC @ 0.0135% followed by imidacloprid 30.5 SC @ 0.12% + spinosad 45 SC @ 0.0135% (1025). Maximum yield loss can be avoided with spray application of thiamethoxam 25 WG @ 0.10% + spinosad 45 SC @ 0.0135% (90.64%) followed by imidacloprid 30.5 SC @ 0.12% + spinosad 45 SC @ 0.0135% (83.16%) as compared to control. [ABSTRACT FROM AUTHOR]

Transparent conductive and polycrystalline zinc oxide (ZnO) thin films were deposited on sodalime glass substrates using the pneumatic chemical spray technique with different amounts (30, 50 and 70 ml) of sprayed solution. During the synthesis, the surface of the substrates was kept at 400, 450 and 500 °C. The effects of the mentioned parameters on compositional, structural, morphological, electrical and optical properties were studied with Rutherford Backscattering Spectrometry, X-ray diffraction, Scanning Electron Microscopy, the Four Point methods and Ultraviolet and Visible Spectroscopy (UVS). The results show that the atomic Zn concentration in the films increases with the volume of sprayed solution and with the substrate temperature. The Band gap energy seems not to be sensitive to the amount of sprayed solution; meanwhile, the higher band gap energy values were obtained in the samples deposited at T s  = 450 and 500 °C. On the other hand, the lower resistivity values were observed in samples deposited with T s  = 450 °C. [ABSTRACT FROM AUTHOR]

The movement and deposition of the droplets sprayed by agricultural unmanned aerial vehicle (UAV) are influenced by the complex downwash flow field of the rotors. Instead of conducting field experiment, a high speed particle image velocimetry (PIV) method was used to measure the movement and deposition of the droplets at different rotating speeds of rotors (1000-3000 r/min) or at different transverse injecting points (20-50 cm away from its nearby rotors) in the downwash flow field of an agricultural UAV with eight rotors and conical nozzles. The maximum speed and size of the high speed zone of the droplets were found greatly influenced by the downwash velocity. The initial spray angle of the nozzle declined with the increase of downwash flow speed. It was found that the downwash velocity could not only change the deposition zone of the droplets, but also influence their distribution. The increase of the downwash velocity would increase the deposition uniformity of the droplets. The nozzle position in the downwash flow field could also influence the deposition of the droplets. When the transverse distance between the nozzle and its nearby rotors increased, the relative deposition near the downwash flow of the rotors increased simultaneously. However, the distance between the deposition peak and the nozzle stayed constant. The initial spray angle of the nozzle was not influenced by the transverse distance between the nozzle and its nearby rotors. The research results could provide a theoretical basis and reference for the optimization of the spray application of multi-rotor UAV to minimize droplets deposition uncertainty. [ABSTRACT FROM AUTHOR]

Copyright of Al-Qadisiyah Journal of Pure Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

FeS pyrite films are used in a variety of applications including solar cells and, the potential scope for their utilization is increasing as their synthetic methods become more economical while maintaining or enhancing their high light absorption coefficients. The glass substrate temperature dependence on the formation of FeS pyrite films was investigated with respect to their optical and physicochemical properties. During the thermochemical spraying process the temperature was varied in the range of 190-290 °C. FeS nanocrystalline (40-70 nm) films, formed as a result of atmospheric spraying with glass substrate temperatures above 260 °C, were observed by SEM. Opto-electronic studies revealed that the nanocrystalline films had a direct band gap (1.3-1.6 eV) with a high light absorption coefficient (α > 7 × 10 cm for λ < 1800 nm). Thus, this study offers an alternative to complicated methods for thin-film formation through spaying technology, for the synthesis of high-quality FeS pyrite films with potential application as high light-absorbing solar energy absorbers. [ABSTRACT FROM AUTHOR]

Nickel-doped zinc oxide thin films (ZnO : Ni) at different percentages were deposited on glass substrates using a chemical spray technique. The effect of Ni concentration on the structural, morphological, optical and photoluminescence (PL) properties of the ZnO : Ni thin films were investigated. X-ray diffraction analysis revealed that all films consist of single phase ZnO and was well crystallized in würtzite phase with the crystallites preferentially oriented towards the (002) direction parallel to the c-axis. The optical transmittance measurement was found to be higher than 90%, the optical band gap values of ZnO thin films decreased after doping from 3.29 to 3.21 eV. A noticeable change in optical constants was observed between undoped and Ni-doped ZnO. Room-temperature PL is observed for ZnO, and Ni-doped ZnO thin films. [ABSTRACT FROM AUTHOR]

Abstract: Indium and fluorine codoped zinc oxide (ZnO:In+F) thin films were deposited on glass substrates by the chemical spray technique. The effect of the dopant concentration ratio in the starting solution, as well as the substrate temperature on the electrical, morphological, structural, and optical properties of ZnO:In+F thin films was studied. A minimum electrical resistivity, in the order of 3.4×10−3 Ωcm, for as-grown films deposited at 475°C from a starting solution containing [In]/[Zn]=3 and [F]/[Zn]=20at.%, was obtained. All the films were polycrystalline, and some differences in the intensity of the peaks and preferential growth, depending on the doping ratios, were observed. The deposited ZnO:In+F thin films showed an average optical transmittance in the order of 85%, in the visible region (400–700nm). The band gap values oscillated around 3.35 and 3.39eV, and a shift towards higher values with the increase of the dopant concentration was observed. The surface morphology of the films was also strongly affected by the dopant concentration ratio, since a variation in both geometry and grain size was observed. [Copyright &y& Elsevier]

Abstract: Aluminum-doped zinc oxide thin films (ZnO:Al) were deposited on sodalime glass substrates by the chemical spray technique, starting from zinc pentanedionate and aluminum chloride. The effect of the substrate temperature on the structural, morphological, optical, and electrical properties was studied. A constant [Al]/[Zn]=3at.% ratio was used. As the substrate temperature increases, the electrical resistance decreases, reaching a minimum value, in the order of 3×10−2 Ωcm, for as-grown films deposited at 475°C. The Hall mobility and carrier concentration for these films were around 0.6cm2/(Vs), and 3.42×1020 cm−3, respectively. Further decrease in the resistivity, in the order of 1.5×10−2 Ωcm, was observed after a heat treatment in vacuum, during 1h, at 400°C. All the samples were polycrystalline, with a variation in the preferential growth. Samples deposited at 450°C show a (002) preferential growth whereas films deposited at higher temperatures present a significant contribution of other planes. As the substrate temperature increases, the morphology shows slight changes, since the grain size increases. The transmittance in the visible region (400–700nm) is high, typically of 85% at 550nm, and band gap values oscillated around 3.3eV. These results show that zinc pentanedionate can be a good candidate for the manufacturing of transparent conductive ZnO:Al thin films. [Copyright &y& Elsevier]

The application of computer and machines for agricultural production has been one of the outstanding developments in Malaysian agriculture, especially in overcoming labour shortages in Oil Palm plantations. The on-line automated weedicide sprayer system was developed at Universiti Putra Malaysia to locate the existence and intensity of weeds in real-time environment and to spray the weedicides automatically and precisely. During the start of the spraying operation, the web camera will initially capture the image of weeds. The computer programme will compute the red, green, blue (RGB) values in the form of computer pixel. These values will be used as reference RGB values to be compared with the RGB values of the weeds captured real-time during the spraying operation. The sprayer nozzle will be turned 'on' or 'off', depending on the percentage or intensity of the green colour pixel value of weeds. The sprayer valve will open the nozzle/s when the camera detected the presence of weeds. The purpose is to reduce wastage, reduce labour, reduce cost, and control environment hazard. [ABSTRACT FROM AUTHOR]

Abstract: Highly transparent and conducting fluorine-doped zinc oxide thin films, consisting of spherical nanometer-sized grains, were synthesized onto soda-lime glass substrate by using a chemical spray unit. The effect of fluorine doping concentration in starting solution was investigated. Both doped and undoped films were preferentially oriented along [002] direction. Electrical resistivity decreases from 5.7 x 10-2 to 8.6 x 10-3 ohm-cm after 1 at.% fluorine doping, and increases for higher doping concentration. However, surface morphology of films obtained at 3 at.% fluorine doping appeared smooth and uniform. A shift of the edge of the optical transmission in the ultraviolet region as a result of fluorine doping was obtained. [Copyright &y& Elsevier]

Abstract: Fluorine-doped zinc oxide (ZnO:F) thin films onto sodocalcic glass substrates, starting from a highly concentrated starting solution (0.4 M) containing zinc acetate and hydrofluoric acid diluted in a mixture of deionized water, acetic acid , and methanol, using the chemical spray deposition technique, were deposited and characterized. The effect of the acetic acid content in the starting solution, and the substrate temperature on the electrical resistivity, structure, morphology and optical characteristics was studied. The samples were polycrystalline in nature, but as the acetic acid content in the starting solution increases, the preferential orientation shows a switching from (002) to (101). For a predetermined deposition temperature, as the acetic acid content increases, the film resistivity values show an increase. The minimum resistivity in the order of 6×10−3 Ω cm was found for the films deposited with the lowest acetic acid content used. The surface morphology varies from agglomerated grains to rod-like shaped grains as a function of the acetic acid content. [Copyright &y& Elsevier]

Abstract: Chemically sprayed aluminum-doped zinc oxide thin films were deposited on glass substrates. The effect of the deposition conditions and the post annealing treatment in vacuum on the electrical, optical, structural and morphologic properties have been analyzed. The films were prepared using two Zn reactants, namely zinc acetate A(Zn) and zinc pentanedionate P(Zn). Aluminum pentanedionate P(Al) was used as the dopant source in both cases. The results show that the doping and annealing of the ZnO thin films enhance mainly the electrical properties. Under optimum deposition conditions a low resistivity and a high optical transmittance of the order of 1.8×10−2 Ω cm and 85%, respectively, were obtained. No significant changes in the optical properties were observed as a consequence of the annealing treatments. All the films show a crystalline structure with a preferred (002) growth i.e. the c-axis is oriented normal to the substrate plane in all the cases. [Copyright &y& Elsevier]

Abstract: Aluminum-doped zinc oxide thin films (ZnO:Al) were deposited on sodocalcic glass substrates by the chemical spray technique, using zinc acetate and aluminum pentanedionate as precursors. The effect of the [Al/Zn] ratio in the starting solution, as well as the substrate temperature, on the physical characteristic of ZnO:Al thin films was analyzed. We have found that the addition of Al to the starting solution decreases the electrical resistivity of the films until a minimum value, located between 2 and 3 at.%; a further increase in the [Al/Zn] ratio leads to an increase in the resistivity. A similar resistivity tendency with the substrate temperature was encountered, namely, as the substrate temperature is increased, a minimum value of around 475 °C in almost all the cases, was obtained. At higher deposition temperatures the film resistivity suffers an increase. After a vacuum-thermal treatment, performed at 400 °C for 1 h, the films showed a resistivity decrease about one order of magnitude, reaching a minimum value, for the films deposited at 475 °C, of 4.3×10−3 Ω cm. The film morphology is strongly affected by the [Al/Zn] ratio in the starting solution. X-ray analysis shows a (002) preferential growth in all the films. As the substrate temperature increases it is observed a slight increase in the transmittance as well as a shift in the band gap of the ZnO:Al thin films. [Copyright &y& Elsevier]

Abstract: Fluorine-doped zinc oxide thin films (ZnO:F) were deposited on Si(100) substrates by the chemical spray technique (CST) from an aged-solution. The effect of the substrate temperature on the morphology and composition of the ZnO:F thin films was studied. The films were polycrystalline, with a preferential growth along the ZnO (002) plane, irrespective of the deposition temperature. The average crystal size within the films was ca. 35nm and the morphology of the surface was found to be dependent on the substrate temperature. At low substrate temperatures irregular-shaped grains were observed, whereas at higher temperatures uniform flat grains were obtained. Elemental analysis showed that the composition of the films is close to stoichiometric ZnO and that samples contain quite a low fluorine concentration, which decreases as a function of the deposition temperature. [Copyright &y& Elsevier]

Abstract: Second harmonic generation (SHG) studies of fluorine-doped zinc oxide (ZnO:F) thin films deposited on soda-lime glass substrates from an aged solution in conjunction with zinc pentanedionate, using the chemical spray deposition technique were carried out. The and independent tensorial components of the quadratic nonlinear optical susceptibility of the ZnO:F thin films were evaluated. Scanning electron microscopy and X-ray diffraction investigations revealed a homogeneous distribution of nanoparticles of similar size and morphology for various samples deposited at different substrate temperatures (ranging from 400 to 525°C). The SHG-technique revealed a clear dependence of the nonlinear optical response with the deposition temperature. Typical optical transmittance and photoluminescence (PL) studies were also performed, from which a bandgap (E g) of 3.3eV was evaluated in films deposited under optimal conditions of conductivity and transmittance. [Copyright &y& Elsevier]

Abstract: Indium-doped zinc oxide thin films were deposited on glass substrates by the chemical spray technique. Hydrated zinc 2,4-pentanedionate was used as zinc source. Four different indium compounds were separately used as dopants (indium nitrate, indium sulfate, indium acetate, and indium chloride). The effect of the thickness on the electrical, structural, morphological and optical characteristics of ZnO:In thin films was studied. Electrical resistivity values corresponding to good conductive electrodes were obtained irrespective of the indium compound used, although a decrease in electrical resistivity is found in all the cases as the film thickness increases, reaching a saturation value of 2×10−3 Ωcm. All films were polycrystalline with a wurtzite phase, and exhibited a (101) preferential orientation almost irrespective of neither the doping source nor thickness. The surface morphology was analyzed by scanning electron microscopy and a strong dependence on the indium compound and thickness was found, since grain geometry variations from rounded to rod-like forms were observed. As the film thickness increases, the film transmittance and the band-gap values decrease. Band-gap energy values were in the range of 3.21 to 3.44eV. [Copyright &y& Elsevier]

Abstract: Transparent and conductive fluorine-doped zinc oxide (ZnO:F) thin films were deposited on glass substrates by the chemical-spray technique starting from a diluted solution of zinc acetate and hydrofluoric acid. The effect of the aging time of the starting solution on the electrical, structural, morphological and optical characteristics of ZnO:F thin films was observed and analyzed. The resistivity of the ZnO:F thin films decreases as a more aged solution is used, reaching a saturation value of 6×10−2 Ωcm. X-ray diffraction reveals that the films are polycrystalline in nature with a (100) preferential growth in almost all the cases. High-resolution scanning electron microscopy clearly reveals that the films are composed of nanoparticles of spherical shape, whose average diameter is in the order of 15nm that matches well with the crystallite size calculated from X-ray diffraction. This result shows that fluorine incorporation effectively inhibits grain growth. This, in turn, produces a porous structure. Also, the increase in the time of aging enhances slightly the transmittance of the films. [Copyright &y& Elsevier]

Abstract: The effect of both the molar concentration of the starting solution and the substrate temperature on the electrical, morphological, structural and optical properties of chemically sprayed fluorine-doped zinc oxide (ZnO:F) thin films deposited on glass substrates is analyzed in this work. All the starting solutions employed were aged for 10 days before the deposition. The results show that as the molar concentration increases, a decrease in the electrical resistivity values is obtained, reaching the minimum resistivity in films ZnO:F deposited from a 0.4 M solution at 500 °C. A further increase in the molar concentration leads to a very slight increase in the resistivity. On the other hand, as the substrate temperature is increased, the resistivity decreases and a tendency towards to minimum value is evidenced; taking the molar concentration as parameter, minimum values are reached at 500 °C. The obtaining of ZnO:F thin films, with a resistivity as low as 7.8×10−3 Ω cm (sheet resistance of 130 Ω/□ and film thickness of 600 nm) measured in as-deposited films is reported here for the first time. The concurrent effect of the high molar concentration of the starting solution, the substrate temperature values used, and the ageing of the starting solution, which might cause polymerization of the zinc ions with the fluorine species, enhance the electrical properties. The structure of the films is polycrystalline, with a (002) preferential growth. Molar concentration rules the surface morphology as at low concentration an hexagonal and porous structure is developed changing to a uniform compact and small grain size surface in the films deposited with the high molar concentrations. [Copyright &y& Elsevier]

Abstract: Transparent conducting indium-doped zinc oxide thin films were prepared on soda-lime glass substrates by the spray pyrolysis technique. The dependence of the electrical, structural, morphological and optical properties on the preparation conditions has been studied. Two main variables, substrate temperature and molar concentration, were varied in the ranges of 425–525°C and 0.05–0.5M, respectively, in order to obtain films with low electrical resistivity and high optical transparency in the visible region. A minimum resistivity value around of 3×10−3 Ωcm was obtained for films deposited from highly concentrated starting solutions, 0.4 and 0.5M. The values of the free-carrier concentration and the electronic mobility were estimated by Hall effect measurements. X-ray diffraction spectra evidenced a preferential orientation along the (101) direction. The surface morphology was clearly affected with the molar concentration variation, leading to a smoother appearance as the zinc concentration in the starting solution is increased. Typical optical transmittance values in the order of 85% were obtained in all the films. [Copyright &y& Elsevier]

Highly conductive and transparent indium-doped zinc oxide thin films were deposited by the chemical spray technique on sodocalcic glass substrates starting from zinc acetylacetonate. The role of the type of alcohols, namely, methanol, ethanol and isopropyl and the substrate temperature on the electrical, structural, surface morphology and optical characteristics of the thin films were studied. The results show that some of the physical characteristics under study are effectively modified by the temperature as well as the kind of the alcohol used. A resistivity value of 3×10−3 Ωcm with a mobility of 6 cm2/(V s) and a carrier concentration of 1021 cm−3 were found for the best films. All the films were polycrystalline fitting well with a hexagonal wurtzite structure. High texture surface, which enhance light trapping was observed in films deposited with an ethanol-containing solution. The transmittance of the films is higher than 85% in all the cases, and a band gap value of around 3.3 eV was also found. [Copyright &y& Elsevier]

Conductive and transparent fluorine-doped zinc oxide, ZnO:F, thin films were deposited at 500°C on glass substrates by the chemical spray technique. Two sets of samples were deposited, based on a fresh and a two-day old starting solution prepared from zinc acetyl acetonate and ammonium fluoride dissolved in a mixture of water and alcohol. The electrical, structural, morphological and optical characteristics of the films as a function of the fluorine concentration in the starting solution were studied. Films with a resistivity as low as 2×10−2 Ω cm, mobility up to 5 cm2/(V s), carrier concentration in the range 1.5–5.7×1020 cm−3 and a transmittance in the range 75–90% were achieved with the old solution. Films were polycrystalline, growing preferentially along the (0 0 2) and (1 0 0) directions, depending on the fluorine concentration in the starting solution. [Copyright &y& Elsevier]

Aluminum-doped zinc oxide thin films, ZnO:Al, were deposited on soda-lime glass substrates by the chemical spray technique. The effect of the Al concentration and the type of solvent (methanol, ethanol and isopropanol) in the starting solution, on the resistivity, structure, surface morphology and optical transmittance of the ZnO:Al thin films was studied. The substrate temperature used was of 500 °C. The resistivity of the films was in all cases below 0.4 Ω cm. The smallest resistivity values, around 1.3×10−2 Ω cm, were obtained using a [Al]/[Zn] ratio of 3 at.% in the starting solution and methanol as solvent. All the films were polycrystalline and their surface morphology changed with the type of solvent employed. Films prepared with methanol and isopropanol showed a broad distribution of particle size. On the contrary, films prepared with ethanol showed an uniform particle size, around 110 nm in average. The optical transmittance was higher than 85% at 550 nm. An increase in the Al concentration produced a shift in the adsorption edge to higher energies. [Copyright &y& Elsevier]

Zinc oxide (ZnO) thin films without intentionally doping were prepared from 2,4-zinc pentanedionate by the chemical spray technique. Electrical, structural and morphological properties of these films as a function of the substrate temperature were studied. A resistivity of 2×10−1 Ω cm, a mobility of 11 cm2/V s, a carrier concentration of 5×1019/cm3 and an average transmittance of 85% in the visible range were obtained for undoped ZnO films prepared at 500 °C, with no post-annealing process. Also, the morphology varies with the substrate temperature. It was found that the surface shows a texture suitable for light trapping, as well. [Copyright &y& Elsevier]

This paper presents a state-of-the-art review of available image sensing technologies and developments for site-specific application of agricultural chemicals. This includes a review of detection features, sensing technologies, system integration, information systems and prototype operational systems. [ABSTRACT FROM AUTHOR]

Copyright of Arab Journal of Plant Protection is the property of Arab Society for Plant Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)