共查询到19条相似文献,搜索用时 140 毫秒
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镍钼修饰的p型硅电极材料的制备和性能 总被引:3,自引:0,他引:3
在半导体p型Si上恒电流沉积纳米晶和非晶Ni-Mo合金薄膜,制备出Ni-Mo合金修饰的半导体p型Si电极镀层.用SEM对膜层进行了表征,测量了两种电极镀层的阴极催化析氢曲线,纳米晶Ni-Mo/p-Si镀层的催比析氢性能较好,测量了光照下纳米晶Ni-Mo/p-Si电极的催比析氢曲线.结果表明, Ni-Mo颗粒尺寸在40~100nm时,光照下电极的析氢过电位比无光照减小了约160mV(电流密度为8 mA·cm-2),催比析氢活性显著提高. 相似文献
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介绍了一种对乳化过程中的温度、流量、pH值及pAg进行控制的平衡双注装置。实验结果表明,该装置能有效地控制卤化银晶体的生长并制备出单分散的乳剂。 相似文献
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确定聚合物共混的相容性最常用的方法是通过测定共混物的玻璃化转变温度(Tg),本文利用DSC-7(Epson)测定了不同共混比的PVA,CS共混物的玻璃化转变温度,结果表明PVA,CS之间有良好的相容性。本文利用扫描电子显微镜(SEM),红外光谱(IR)和X-射线衍射(XRD)等现代分析仪器,对研制的多元酸交联的PVA-CS/PSF膜结构进行了观察测试,探讨了膜结构与性之间的关系。 相似文献
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偶联剂KH和聚合物PVA在硫铝酸盐—MDF水泥中的作用机理 总被引:2,自引:0,他引:2
以硫铝酸盐水泥为基材,采用有机聚合物PVA,并且在MDF水泥中添加偶联剂KH,制备出抗折强度大于170MPa,抗压强度达240MPa的新型MDF水泥。同时,借助于X射线光电子能谱分析(XPS),红外光谱分析(IR)等测试手段研究了偶联剂KH和聚合物PVA的硫铝酸盐-MDF水泥中的作用机理。 相似文献
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以硫铝酸盐水泥为基材,采用有机聚合物PVA,并且在MDF(Macro—Defect—Free)水泥中添加偶联剂KH,制备出抗折强度大于170MPa,抗压强度达240MPa的新型MDF水泥、同时,借助于X射线光电子能谱分析(XPS),红外光谱分析(IR)等测试手段研究了偶联剂KH和聚合物PVA在硫铝酸盐-MDF水泥中的作用机理 相似文献
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本文制备了四种不同粒度的超微粒AgBr照相乳剂,用X射线衍射技术对其粒子的大小进行了测定;观察到乳剂的紫外吸收峰随晶体颗粒的减小表现出逐渐蓝移;本文提出晶体表面的悬键的存在使得纳米晶体的平均键能升高,并对纳米AgBr乳剂的量子尺寸效应进行了解释。 相似文献
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AbstractThe electronic properties of silver clusters formed on the surface of reduction- sensitized octahedral and cubic AgBr emulsions were studied. Prior to sensitization with dimethylamineborane, SnCl2 or high pH, these emulsions had the same efficiency. The results suggest that the octahedral emulsion has more potential to achieve a higher maximum speed increase. This difference may be due to fewer available sites for silver cluster formation on cubic surfaces. Gelatin concentration studies showed that the gelatin and/or impurities do play a role in silver cluster formation by high pH treatment. The precise role of OH? is uncertain. 相似文献
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T.R. Keenan 《成像科学杂志》2013,61(3-4):113-115
AbstractThe influence of several alkaline processed IAG gelatins on the chemical sensitization of an ammoniacal silver bromo/iodide (AgBr/l) emulsion has been studied using the Rapid Emulsion Sensitometric Evaluator (RESE). Simple calcium effects on the thiosulphate chemical sensitization process were minimized by adjustment of calcium content prior to sensitization. Results of relative optimum ripening time and relative speed are discussed. 相似文献
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A. V. Khaneft 《Inorganic Materials》2003,39(3):299-303
An equation is derived for the ionic conductivity of silver halide emulsion grains with dimensions comparable to the Debye length of intrinsic defects. The conductivity of the grains is shown to be inversely proportional to the grain size. The surface potential distribution depends on both the shape and size of the grains. The surface charge density, surface potential, and volume potential are estimated for octahedral, cubic, and tabular AgBr grains. 相似文献
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本文报导了制备黑白反转照相纸感光乳剂的一些研究工作,该反转相纸用于《即拍即成》照相,感光度为ISO25。地一系列相关的技术问题进行实验研究并获得了明确的结论。 相似文献
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The explanation for the direction of photocurrent due to the Dember effect in silver halide emulsion grains is given for the situations where spectrally unsensitized silver halide grains were exposed to blue light and spectrally sensitized grains to green-red light.The change of the Dember effect by varying the condition of the emulsion grains, that is, atmospheric condition, preexposure, chemical sensitization and desensitization, temperature dependence of photovoltage relaxation, the wavelength of the incident light and the ionic conductivity of silver halide grains, was observed and discussed. 相似文献
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The determination of the sulphur in the silver bromide grains of a photographic emulsion shows that the sulphur contents are several times greater than that corresponding to the gelatin adsorbed to the grains. The significance of the sulphur atom for the occurrence of effective chemisorption is indicated. 相似文献
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The determination of the sulphur in the silver bromide grains of a photographic emulsion shows that the sulphur contents are several times greater than that corresponding to the gelatin adsorbed to the grains. The significance of the sulphur atom for the occurrence of effective chemisorption is indicated. 相似文献
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Emulsion grains have been deformed by bending an emulsion layer coated on film, and the effects of deformation on the dispersity ol photolytic silver and on the number and distribution of development centres have been studied. The observations show thai a major effect of such treatment is to increase the number of sues within a grain at which silver specks can be nucleated.The usual sensitomelric effect of such changes is to increase sensitivity on internal-image development at the expense of sensitivity on surface-image or conventional development. However, it is shown that surface desensitizalion may be accompanied sometimes by internal desensitization rather than sensitization. The internal desensitization can be attributed to competition between the increased number of internal sensitivity centres. Support for this view was obtained from the fact that changes in the effect of deformation on storage prior to exposure (decrease of surface desensitization. decrease of internal sensitization or desensitization I were associated with a reduction in the number of centres ,il which internal silver could be nucleated.A further effect of deformation noted with coatings of lodohromide emulsions (but probably general with respect to halide) is to decrease the luminescence intensity at low temperatures, particularly at low intensities of excitation, and to increase the time required for luminescence to reach maximum intensity. These observations show that deformation introduces new recombination centres and electron traps into emulsion grains The connection between the effects of deformation on sensitomelric properties and luminescence properties have been studied as a function of grain size and chemical sensitization in a series of animoniacal emulsions. The findings confirmed that damage to the grains is responsible for the loss of sensitivity on conventional development, and that chemical sensitization, though reducing desensitization hv deformation, has no influence on the grain disorder introduced by this latter treatment. 11 is thought unlikely that the new recombination centres play any significant part in the desensitization by deformation of emulsions chemically sensitized so as lo be al or near optimal speed, but some contribution would appear feasible in the case of emulsions at a low level of sensitization. 相似文献