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1.
高感光度乳剂制备中 ,如何利用好碘的掺杂技术 ,对于提高乳剂感光性能起至关重要的作用 ,本文针对碘溴化银T颗粒乳剂中不同的加碘方式、碘的不同分布及不同的加入量 ,对其晶型和感光性能的影响进行了综述。  相似文献   

2.
酰基苯肼的感染显影及反差促进剂的作用   总被引:9,自引:4,他引:9  
研究了六种结构不同的酰基苯肼化合物(通式:R—PhNH—NH—COR′)对卤化银乳剂感光性能的影响。结果表明,感染显影作用程度与酰基苯肼的结构有密切的关系。另外本文还就反差促进剂(醇类化合物和胺类衍生物)的作用及其机理进行了较深入的研究。事实说明,显影液中加入反差促进剂,不但能消除单独使用酰基苯肼时出现的“自阻”效应,而且还大大促进了感染显影的进行,提高了乳剂的反差和感光度。同时,本实验在应用高压液相色谱、色-质联仪、顺磁共振等方法对酰基苯胼的还原反应产物及反应中间物进行分析的基础上,更加明确地解释了感染显影和反差促进的作用机理。  相似文献   

3.
多层结构颗粒乳剂微晶的制备   总被引:1,自引:0,他引:1  
综述了多层结构乳剂的组成,结构及制备,并讨论了颗粒中碘对乳剂感光性能的影响及碘的分析测试方法。  相似文献   

4.
本文利用双注仪制备出中空立方体碘氯溴颗粒乳剂并研究其感光性能.结果表明:由于中空颗粒具有独特的孔洞结构,使位错、缺陷增加,填隙银离子浓度增加和电子陷阱增多,潜影形成效率提高,从而达到提高乳剂感光性能的目的.  相似文献   

5.
本工作应用双注仪制备了一系列不同碘含量的切角立方体核壳乳剂,用紫外光度法测定了它们的光吸收,用介电损耗法和微波光导法分别测定了它们的离子电导及光电导。结果表明,乳剂微晶体的光吸收和离子电导率都随着碘含量的增加而增加,光电导也随碘含量增加而增大,光电子衰减遵循二级反应动力学过程。碘的引入以及立方体切角使立方体乳剂微晶体的感光性能成倍地增长。  相似文献   

6.
食用盐中碘的价值越来越被大家重视,世界上碘在食用盐中的加入一般有碘化钾和碘酸钾两种。碘酸钾能稳定地存在于食用盐中,而碘化钾要求非常严格的保存和使用条件,否则就会变质。我国食用盐中一般加入的都是碘酸钾,但是一些生产粗盐的小产家可能加入碘化钾。设计了采用比色法区分食用盐中碘的成分,ICP-MS法测定碘的含量的办法。在分析碘含量时确认准确度、精密度、检出限、加标回收率等指标。检出限能达到0.027 mg/g,加标回收率在92%至105%之间,精密度指标RSD(%)在1.41%到3.74之间,国家标准物质测定结果在规定范围内。  相似文献   

7.
溴化银乳剂中Ag2掺杂的位置效应研究   总被引:1,自引:0,他引:1  
使用微机控制的双注仪,在晶体生长过程的不同时刻,加入一定浓度的二甲基胺硼烷(DMAB),制得了一系列Ag2处于不同掺杂位置的立方体溴化银微晶乳剂.对这些乳剂感光性能的研究表明:1)他掺杂乳剂与未掺杂乳剂相比,感光度有显著提高;2)心掺杂乳剂可同时与常规的硫加金化学增感和光谱增感进行协同增感;3)心掺杂接近微晶表面时乳剂感光度的增幅最大;4)在本实验条件下,掺杂乳剂的灰雾均保持在较低的水平。  相似文献   

8.
应用双注仪制备了碘含量为30 mol%的碘溴化银乳剂微晶体,然后采用二次乳化法形成外壳,制备出核壳比分别为1:1,1:2,1:3,1:4的一组核壳乳剂。采用X射线能谱法对乳剂单个颗粒进行微区成份分析,证明乳剂微晶存在富碘核与贫碘壳,且随核壳比的增加。颗粒外缘碘离子浓度减小;应用UV-240紫外可见光度计和微波光导仪测定了乳剂微晶的光吸收和光电导。测量结果表明,由于碘含量减小与颗粒直径增加两因素的影响,乳剂的光吸收能量大致相同;随核壳比的增加,乳剂的光电导估号上升;当核壳比等于1:3时,光电子寿命最长。对乳剂的感光性能与上述各种性质的关系进行了讨论。  相似文献   

9.
本文制备了一系列结构不同的片状卤化银晶体,用扫描透射电子显微镜和X射线能谱仪相结合的方法对单个微晶进行了亚显微结构分析。半定量地测定了碘离子在不同结构的片状晶体中的分布,同时测量了各样品相应的介电损耗、Dember效应的光电压及高低照互易律失效。结果表明,在四种碘离子分布不同的片状卤化银晶体中,其微晶的离子电导率、高低照互易律失效、Dember效应的光电压衰减都随微晶中碘离子的分布不同而异,而且与乳剂的感光性能有很好的对应关系。  相似文献   

10.
研究了K4[Fe(CN)6]掺杂剂对溴碘化银颗粒乳剂感光性能的影响,结果表明掺杂剂的掺杂量、掺杂位置以及在乳剂颗粒内部的分布区域对乳剂的感光性能都有影响。掺杂位置接近表面或接近内核时效果明显,掺杂位置接近富碘区域时,乳剂的感光度上升的不明显,较佳的掺杂量为1×10-6mol/molAgNO3。  相似文献   

11.
A simplified procedure for the determination of betaine in liver   总被引:5,自引:0,他引:5  
A. J. Barak  D. J. Tuma 《Lipids》1979,14(10):860-863
A convenient procedure for the determination of hepatic betaine levels is described. The method takes advantage of ethanol precipitation to rid acidified tissue extracts of interfering substances. Betaine is reacted with potassium triiodide to form betaine periodide, which is selectively precipitated via pH adjustment. The precipitate of betaine periodide is dissolved in ethylene dichloride and measured spectrophotometrically. The method is specific, accurate, and simple and showed recoveries of from 97 to 103% at two different levels of added betaine. The applicability of the method was shown when it was demonstrated that diets containing different amounts of choline influenced levels of hepatic betaine.  相似文献   

12.
Emulsion stability, electrophoretic mobility, and interfacial tension of chloroform, cyclohexane, and n-hexadecane-potassium laurate solution were determined as a function of acidification by concentrated HCl. The stability of these emulsions were related to the presence or absence of lauric acid at the interface. It was found that a lauric acid-laurate interfacial film was responsible for the enhanced stability in the case of cyclohexane and n-hexadecane emulsions, while no such mixed film existed in the case of chloroform. The interfacial ionization markedly affects the distribution of ions in solution closer to the interface. The concept of surface pH was applied. Differences of up to 2 pH units between bulk and surfaces were found with these systems. Both cyclohexane and hexadecane have major stability peaks which lie at ca. the same surface pH of 5.9 ± 0.2, irrespective of the initial potassium laurate concentration or bulk pH. It is concluded that the stability of these emulsions can be explained when the role played by the interfacial ionization is taken into consideration.  相似文献   

13.
When a nonionic surfactant, such as hexaoxyethylene glycol dodecyl ethers (6ED) is added to an aqueous iodine solution in the presence of potassium iodide, some spectral changes corresponding to the interaction of iodine-potassium iodide mixture with 6ED are found above the critical micelle concentration (CMC) of 6ED. The absorption maximum bands of complexes formed between 6ED and iodine are significantly different from those formed between 6ED and iodine-potassium iodide mixture in aqueous solution. The complexes of iodic compounds (such as iodine, triiodide ion and polyiodide ion) with 6ED show absorption bands at 390 nm, 370 nm and 385 nm which are assigned to an interaction between iodine-6ED, triiodide ion-6ED and polyiodide ion-6ED, respectively. When the concentration of polyethylene glycol (PEG, MW=200–600) becomes high in aqueous triiodide ion solution, the maximum absorption wavelength of triiodide ion solution also shifts toward 370 nm, similar to that of the triiodide ion-6ED complex. If it is assumed that the absorbance between I3 ? and the EO chain in 6ED is the same as that between I3 ? and the EO chain of PEG, the concept of effective EO number can be applied to explain the behavior in the absorption spectra among I3 ?, 6ED and PEG. Here, the effective EO number is defined as the product of EO chain length and concentration of each 6ED and PEG in the complexes. The effective EO number and concentration of PEG decrease in the triiodide ion-PEG complex as the molecular weight of PEG becomes large. Moreover, the effective EO number and concentration of 6ED are lower than those of PEG at all maximum absorption wavelengths.  相似文献   

14.
A simple procedure for the determination of levels of free choline and phosphorylcholine in hepatic tissue is outlined. The method makes use of the enzyme acid phosphatase to liberate choline from phosphorylcholine and incorporates the ability of choline to react with potassium triiodide to yield choline periodide for the measurement of choline and phosphorylcholine in liver. The method is accurate for both entities (recovery of 97–100% for choline and 92–98% for phosphorylcholine). For phosphorylcholine, the method is markedly simpler than other methods previously described and the results for normally fed rats are of the same order of magnitude. The applicability of the method was shown when it was demonstrated that diets containing different amounts of choline influenced the level of choline and phosphorylcholine in liver.  相似文献   

15.
采用预乳化及种子乳液聚合方法制备了纳米二氧化钛/丙烯酸酯复合乳液,研究了丙烯酸(AA)、过硫酸钾(KPS)、乳化剂及纳米二氧化钛用量对聚合反应稳定性的影响,并采用红外光谱对复合乳胶膜的结构进行了表征。结果表明:当AA、KPS、乳化剂和纳米二氧化钛的用量分别为3.0%,0.5%,3.3%和2.0%时,体系中的凝胶较少,具有良好的聚合反应稳定性。  相似文献   

16.
本制备了一种内部增感的核壳乳剂,其核经增感到一定程度后,表面形成堆积银原子作为空隙陷阱。该乳剂与表敏乳剂混合后,可提高感光度、反差和最大密度。本研究了内增感乳剂制备过程影响因素,并对混合体系作用机理进行了初步探讨。  相似文献   

17.
Results of diffusion coefficient measurements of triiodide in a mixture of two ionic liquids (1-methyl-3-propylimidazolium iodide and 1-butyl-3-methylimidazolium tetrafluoroborate) at 25 °C are described in this paper. Four electrochemical methods for measuring diffusion coefficients of triiodide were evaluated for their reliability and performance, including impedance spectroscopy and polarization measurements at thin layer cells as well as cyclic voltammetry and chronoamperometry at microelectrodes of different radii. Viscosities of the blends were measured to investigate the transport behaviour of triiodide ions used in Grätzel-type dye-sensitized solar cells.  相似文献   

18.
宿志刚 《广州化工》2011,39(8):27-28
论述了铑催化剂回收的现状,介绍从铑体系催化剂合成醋酸装置排出的废料中,回收铑,并将其转化成可供装置使用的三碘化铑的方法。从产品操作复杂程度、产品纯度、收率,对比三种制备三碘化铑工艺的方法,分析各工艺优缺点以及除杂对于铑纯度的影响。并对铑回收在醋酸行业的发展前景进行了展望。  相似文献   

19.
A microporous glass membrane with a narrow-range pore size was applied for the microfiltration of egg yolk phospholipid emulsions. The oil-in-water and water-in-oil emulsions were successfully filtered using the membrane without any coalescence of oil droplets or the breakdown of the emulsions. The filtrated oil-in-water emulsion was stable for at least 6 wk when stored at 5°C. The results obtained suggest that the technique would be valuable for the precise filtration of emulsions for food uses as well as intravenous fat and/or drug carrier emulsions, and offer the stabilization of the emulsions.  相似文献   

20.
This paper reports an investigation by fast atom bombardment mass spectrometry (fabms) and X-ray photoelectron spectroscopy (xps) of the nature of surfaces of films cast from various emulsion adhesives against air and against polystyrene or polytetrafluoroethylene (ptfe) surfaces. An objective was to ascertain the extent to which the nature of the surfaces of films derived from emulsion adhesives depends upon the nature of the substrate against which the film is cast. The emulsion adhesives contained copolymers of vinyl acetate with vinyl neodecanoate (vaw), with ethylene (vae1, vae2, vae3) and with n-butyl acrylate (vaba). FABMS spectra show that the compositions of the air-dried surfaces of the films from the vavv, vae1, and vae2 emulsions are essentially those of the respective copolymers, that the surfaces of films from the vaba adhesives comprise mainly copolymer, but there is some dodecylbenzenesulphonate surfactant also present, and that the composition of the surface of films from the vae3 emulsion is dominated by potassium ions. The fabms spectra indicate no differences between the surfaces of vae3 adhesive films cast against polystyrene and ptfe on the one hand, and the surface of vae3 adhesive dried in air on the other. The fabms spectra clearly demonstrate that interfacial failure occurs between vae3 adhesive films and polystyrene and ptfe substrates when the films are separated from the substrates. XPS spectra show that the air- and polymer-cast surfaces of films from vae3 and vaba emulsions are very similar, and that the surfaces of films from the vae3 emulsions contain 5–6% of potassium together with significant levels of carboxylate moieties.  相似文献   

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