The Effect of Chemical Sensitization and Halogen Composition of the Emulsion on Spectral Sensitization*

The relative quantum yield of a spectral sensitizing dye and its desensitizing effect on the blue sensitivity of emulsions, different in halogen composition and chemical sensitization, were measured. The results show that the relative quantum yield of this spectral sensitizer increases and that the desensitization of the blue sensitivity decreases with chemical sensitization and increasing ratio of bromide versus chloride.     

Sulphur Sensitization: Measurement of the Activation Energy

The activation energies of sulphur sensitization have been measured, using a number of sensitometric parameters and four ensitizers: sodium thiosulphate, allylthiourea, thiourea and sodium sulphide. or any sensitizer. the activation energy is the same for all sensitometric parameters. For all four sensitizcrs, the activation energies are surprisingly similar: sodium thiosulphate 32.2, allylthiourea 37.4, thiourea 34.1 and sodium sulphide 35.1 k cal/g mol.     

Sulphur Sensitization: The Effect of Sensitizer Concentration on the Constitution of Fog and Sensitivity Centres

Coatings prepared from emulsions sensitized with a range of quantities of thiourea have been treated with dilute solutions of chromic acid and gold thiocyanate prior to exposure and development. The effect of the oxidizing agent and gold treatment on the fog centres depends on the condition of sulphur sensitization. The results can be explained if fog centres consist of both silver and silver sulphide. The relative proportions of these two components are related to the quantity of sulphur sensitizer added to the emulsion.     

Impact of Calcium and Methionine on the Variability of a Sulphur and Gold Sensitization on a Bromoiodide Emulsion

Abstract

Chemical sensitization uniformity requires tight batch-to-batch control of components of gelatin as well as the non-gelatin components that are present. Chemical sensitization sensitivity to variations in methionine and calcium was examined using a bromoiodide emulsion at fixed levels of sulphur and gold sensitizer. Hydrogen peroxide treatment of gelatin was used to generate a series of partially oxidized gelatins with varying methionine content. Calcium variation was examined by choosing gelatin with known natural variations in calcium and by addition of calcium salts to deionized gelatins. Sensitometric changes were seen as a function of both calcium and methionine variation. Results indicate that methionine and calcium must be carefully controlled to minimize photographic change.     

The Rate of Sulphide Formation During Photographic Sulphur Sensitization: Measurement of Proton Evolution

A method for measuring the production of protons in a photoemulsion has been applied to the measurement of the sulphur senSitizatIOn reaction. The formation of sulphide from conventional quantities of sensitizer was followed continuously in the digesting emulsion. Reactions of several different sensitizers generally obeyed first order kinetics, although in some cases an induction period was obferved. The generally written reaction for thiosulphate was confirmed. The results did not support a sensitization mechanism involving en lanced reaction at the sensitivity specks.     

非晶态硒碲材料中卤族元素掺杂对空穴陷阱的影响

用静电放电方法研究硒碲材料中卤族元素掺杂对空穴陷阱的影响。结果表明卤族元素掺杂增加了硒碲材料的光量子效率η和光生载流子漂移长度μτE.而体陷阱积分密度 N_(?)降低以及空穴深陷阱态分布减小,说明硒碲材料中卤族元素掺杂使得浅空穴陷阱密度增大。     

关系营销理论探讨--三种理论的区别和联系

关系营销是一种新型的营销理论，它是随着经济技术的发展和竞争的日益激烈而逐步发展起来的。对于关系营销不同角度的研究形成了不同的理论学派。本文介绍了在关系营销研究中具有代表性的三种理论学派，即承诺－信任理论、六市场模型和关系、网络、互动理论，指出这三种理论是从不同的层面研究关系营销的，尽管其研究角度不同，但是理论之间存在着一定的联系。认识到这一点，对于企业营销管理的研究实践活动具有重要的意义。     

支化聚苯乙烯碳卤末端的稳定化改性

用十八羧酸钠为反应试剂,对经原子转移自由基聚合反应(ATRP)合成的支化聚苯乙烯(BPS)进行碳卤末端稳定化改性。采用红外光谱(FT-IR)、核磁共振(~1H-NMR)、凝胶渗透色谱(GPC)、多角激光散射(MALLS)、差示扫描量热(DSC)以及热重法(TG)对改性反应过程及改性前后的聚合物进行表征和分析。结果表明,十八羧酸钠可以和BPS的碳卤末端反应,将不稳定的碳溴末端转变成热稳定的酯键,改性后聚合物的分子质量和支化程度均有所提高,玻璃化转变温度(T_g)升高了23.3℃,并且TG结果证实改性后聚合物热稳定性提高。     

对乳化基质快速敏化的几点认识

敏化是乳化炸药(膏状)生产的重要环节,通过对敏化剂加入量和敏化温度的探讨,以求认清敏化过程对乳化炸药密度、爆炸性能和贮存性能的影响.     

On the Possibility of Increasing the Effect of Sensitization

It has been found that the relative quantum yield of sensitization for a wide range of polymethene dyes may be raised at the expense of the removal of excess brome ions in the emulsion, as well as introducing some anionic and other surface active substances into it. Here, a considerable increase occurs both in the general and the spectral sensitivity of photographical layers.     

Effect of Long-Term Heat Treatment on the Acceptor Behavior of Gold in Silicon

Data are presented on the electrical activity of Au in Czochralski Si heat-treated and diffusion-doped under various conditions. The results are interpreted in terms of force fields responsible for changes in the concentration of electrically active centers. Long-term heat treatment between 700 and 1050°C is shown to have a significant effect on the acceptor behavior of Au in diffusion-doped Si. The concentration of Au acceptors is sensitive to the surface condition in the course of heat treatment: a tungsten coating increases the Au concentration in the bulk of diffusion-doped Si.     

现场混装乳化炸药化学敏化影响因素分析

化学敏化是一种广泛采用的、方便快捷的敏化方式,相对物理敏化而言,化学敏化受较多因素影响,但缺乏对影响因素的系统性分析。研究了NaNO_2用量、pH、不同强度酸、促进剂、温度等对化学敏化的影响。研究表明,通过提高体系中的NaNO_2浓度、温度等,提高NaNO_2的活度,能够显著提高发泡速率;采用中强酸酸度调节剂要比添加柠檬酸或醋酸获得更快的发泡速率;降低体系的pH能够促进发泡反应进行;采用M2+作为敏化促进剂,能够实现低温敏化,其质量分数达到35%时,敏化速率最快。研究过程中还发现,发泡速率过快,容易产生较多的NOx气体,乳化基质发黄,酸性较强时情况更为严重;分散相的pH过低,乳化基质质量较差,极易破乳。发泡速率过快,非常容易产生无效大气泡,生产时应适当控制发泡速率,以期获得最佳的敏化效果。     

浅谈影响乳胶基质物理敏化密度的因素

文章介绍了乳化炸药及其敏化技术,分析了膨胀珍珠岩的粒度、憎水性、加入量、混拌温度、掺混时间及乳胶基质黏稠度等因素对乳胶基质物理敏化密度的影响。同时提出了加入膨胀珍珠岩2%~3%,敏化密度1.05~1.15g/cm3、掺混时间60~90 s等相应的最佳控制参数和措施来减少影响乳胶基质物理敏化密度的因素。进而达到提高乳化炸药产品质量的目的。     

乳化炸药不合格品再处理敏化参数的研究

为了研究敏化剂添加量及敏化温度对乳化炸药不合格品处理的影响，建立了独立的乳化炸药不合格品处理生产线，对乳化炸药不合格品进行了返工处理试验及生产运行。根据试验及生产运行结果,确定了返工乳化炸药不合格品处理过程中的敏化工艺参数:发泡剂和促进剂尿素添加质量分别占混合基质质量的0.20%~0.26%和0.06%~0.10%，敏化温度控制在44~54 ℃，敏化后样品密度控制在1.10~1.24 g/cm³。为了验证敏化工艺参数的合理性，对返工后的乳化炸药的爆速、猛度及殉爆距离进行了试验测试。测试结果表明，返工后乳化炸药的性能均符合乳化炸药的质量要求。     

受主掺杂对ZnO片式压敏电阻材料性能的影响

研究了一价受主Li^＋对ZnO片式压敏电阻材料的电性能和晶界电参数的影响。材料中添加适量的Li^＋离子,可提高压敏电阻的非线性系数、改进器件的漏电流特性。当Li^＋离子添加量从0增加至300mol／ppm时,晶界势垒高度φB由0.7eV增加为0.87eV,晶粒中载流子浓度ND由2.2×10^23／m^3下降为8.5×10^22／m^3,ZnO的电阻率ρg由1.02Ω·cm增加为1.98Ω·cm。     

高温敏化工艺乳化炸药储存期影响因素分析

文章对静态乳化与高温在线敏化工艺制备乳化炸药的储存期的影响因素做了分析,解决了该种工艺条件下生产乳化炸药储存性能不稳定的问题。通过严格的工艺过程控制,如使用符合工艺条件的优质原材料制备的乳化炸药,乳化炸药储存期有了明显的提高。     

乳化炸药中敏化气泡的稳定性

文章主要叙述乳化炸药中敏化气泡的形成机理及其与炸药稳定性的关系，提出了增加炸药稳定性的方法。     

影响感红染料光学增感的主要因素

本文通过试验数据，结合自己的实践经验，简单分析讨论了激光胶片用感红增感染料在用于乳剂光学增感时影响其增感效果的主要因素。