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排序方式: 共有2217条查询结果,搜索用时 15 毫秒
1.
F.T. Munna Vidhya Selvanathan K. Sobayel Ghulam Muhammad Nilofar Asim Nowshad Amin Kamaruzzaman Sopian Md. Akhtaruzzaman 《Ceramics International》2021,47(8):11003-11009
In this study, dilute chemical bath deposition technique has been used to deposit CdZnS thin films on soda-lime glass substrates. The structural, morphological, optoelectronic properties of as-grown films have been investigated as a function of different Zn2+ precursor concentrations. The X-ray diffractogram of CdS thin-film reveals a peak corresponding to (002) plane with wurtzite structure, and the peak shift has been observed with the increase of the Zn2+ concentration upon formation of CdZnS thin film. From morphological studies, it has been revealed that the diluted chemical bath deposition technique provides homogeneous distribution of film on the substrate even at a lower concentration of Zn2+. Optical characterization has shown that the transparency of the film is influenced by Zn2+ concentration and when the Zn2+ concentration is varied from 0 M to 0.0256 M, bandgap values of resulting films range from 2.42 eV to 3.90 eV while. Furthermore, electrical properties have shown that with increasing zinc concentration the resistivity of the film increases. Finally, numerical simulation validates and suggests that CdZnS buffer layer with composition of 0.0032 M Zn2+ concentration would be a promising candidate in CIGS solar cell. 相似文献
2.
John Bensted 《Cement and Concrete Composites》2003,25(8):873-877
Two main formation routes for thaumasite exist below 15 °C. One is the direct route from C–S–H reacting with appropriate carbonate, sulfate, Ca2+ ions and excess water. The other route is the woodfordite route from ettringite reacting with C–S–H, carbonate, Ca2+ ions and excess water, in which thaumasite arises through the intermediate formation of the solid solution woodfordite. The woodfordite route for thaumasite formation appears to be relatively quicker (although still slow) than the direct route, presumably because with the former the ettringite already has the octahedral [M(OH)6] units that can facilitate the critical change from [Al(OH)6]3− to [Si(OH)6]2− groupings. Both routes are mutually dependent on each other. The presence of magnesium salts can modify the path to thaumasite formation. High pressure might be able to stabilise [Si(OH)6]2− groupings and allow thaumasite to become formed above 15 °C. This possibility is discussed. 相似文献
3.
4.
用流动微量量热法研究了十二烷基硫酸钠(SDDS)和十二碳羧酸钠(SL)在克拉玛依油田九区和乌尔禾区油砂上的吸附,简要地计论了吸附机理。所得实验结果表明,SL 在油砂上的吸附强度比 SDDS 的要大,在相当低的浓度下即可迟到饱和吸附。 相似文献
5.
Mirona K. Mironova 《Cement and Concrete Research》2002,32(1):9-15
The paper treats complex phenomena that accompany the diffusion of sulfate ions into cement paste or systems. The ion distribution within the material was studied by designing a specific diffusion model. The model accounts for two phenomena: capillary filling with products of the chemical reactions and the subsequent liquid push out of the capillary. The approach allows to quantify the concentration of free ions having penetrated the cement stone and that of chemically reacted ions, and to assess the liquid push out. Experimental data are also presented. 相似文献
6.
本文提出用尿素作为pⅡ调节剂,加快硫酸亚铁单液法调剖剂中亚铁离子在地层温度下的沉淀,增大沉淀率,提高封堵效能。岩芯流动试验结果表明,15%FeSO4.7II 2O/5%尿素调剖剂体系的封堵能力比不含尿素的体系增大近一倍。 相似文献
7.
Roberta Bomparola Alessandro Lavacchi Ugo Bardi 《Surface & coatings technology》2007,201(24):9485-9490
The influence of temperature on the kinetics and the morphology of silver deposits obtained from an air and water-stable ionic liquid (the 1-butyl-3-methyl imidazolium tetrafluoroborate) was studied by means of cyclic voltammetry and chronoamperometry. The nucleation and growth mechanisms have been investigated and the effect of temperature evaluated up to 200 °C. Dense, pure and very thin (about 0.3 μm) silver coatings, with decorative properties, have been obtained on commercial copper electrodes at different temperatures. The characterization of the deposits morphology has been performed by visual investigation and SEM microscopy. Data about thickness were acquired by Calotest® measurements. The deposits result constituted by pure silver as determined by combination of EDX microanalysis and Auger Electron Spectroscopy (AES). The deposition method promises to be a new, environmentally friendly, method for silver electrodeposition which is the reason for the absence of cyanide and volatile toxic solvents in the electroplating bath. 相似文献
8.
毛/涤纱分散/酸性(媒染)染料一浴法筒子染色工艺,在100℃条件下能满足毛、涤两种纤维同时上染,染色产品具有着色深浓鲜艳,色泽一致,各项牢度符合要求,对纤维无损伤等优点,从而缩短生产时间,降低成本,提高经济效益。 相似文献
9.
CdS thin films and bulk precipitates were obtained by chemical bath deposition (CBD) in a well-closed reactor. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, thermal analysis, elemental analysis and leaching have been used to characterize solids and thin films. It has been shown that the proportion of cadmium cyanamide in solids may vary from about 50% to 2% according to physicochemical conditions in solution (time after CBD, ammonia concentration) and that CdO results from CdCN2 after air annealing of thin films. This last step also increases the crystallinity of the films. 相似文献
10.
微酸性光亮锡铅合金镀液分析方法 总被引:1,自引:0,他引:1
提出锡铅合金液中Sn^2+,Sn(IV),PB^2+、EDTQA、柠檬酸三钠的分析方法。 相似文献