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71.
The leucite crystallization kinetics from a hydrothermally derived precursor seeded with nano-crystalline leucite was investigated by X-ray diffraction and non-isothermal differential thermal analysis. The nano-crystalline leucite was prepared by high-energy milling of high-purity leucite powder and the leucite precursor was prepared by the hydrothermal method of silica sol, aluminum nitrate, and potassium nitrate. After the seeds were introduced, the crystallization temperature of the precursor was lowered by 100°C and the transition phase kalsilite did not appear during the crystallization process. When the seeded precursor was heat treated at 700°C, a small amount of cubic leucite was stabilized to room temperature. The seeded precursor showed an exothermic peak between 800° and 920°C under different heating rates. The activation energy for the growth of leucite from the seeded precursor was 256(SD9) kJ/mol.  相似文献   
72.
The effects of pH, ferrous ion and hydrogen peroxide dosage on the decolorisation and mineralisation of CI Reactive Black 8 by the Fenton process with/without ultrasonic irradiation were investigated. It was verified that the presence of ultrasonic irradiation did not enhance the decolorisation of CI Reactive Black 8 significantly by Fenton's reagents, but it enhanced the chemical oxygen demand removal efficiency. The enhancement was more pronounced for lower (<0.89 mm) or higher (>1.78 mm) ferrous ion dosage. The optimal pH for chemical oxygen demand removal was 3.0. Chemical oxygen demand removal efficiency increased with the increasing H2O2 dosage and reached the highest level at 5.88 mm, but further increase in H2O2 dosage would not increase removal efficiency significantly.  相似文献   
73.
混合电解质NaBr+NaAc十H_2O体系的活度系数的测定   总被引:3,自引:0,他引:3       下载免费PDF全文
闫卫东  刘卫东 《化工学报》1993,44(6):746-751
用电势法测定了298.15K以及I为0.1、0.5、1.0、1.5、2.0、2.5和3.0 mol/kg时,NaBr在混合电解质溶液NaBr+NaAc+H_2O中的活度系数.实验结果用Harned、SRJ和Pitzer方程拟合,得到各种方程的相互作用参数,由拟合的标准偏差得知,Pitzer方程的拟合精度略好于前2个方程.用Pitzer混合参数θ_(Br-Ac)和ψ_(Br-Na-Ac)计算了NaAc在该混合体系中的活度系数和体系的过量Gibbs自由能.  相似文献   
74.
阐述了SOAP通信协议的构成和实现机制以及与相似协议的比较。基于它的跨平台的能力,将其运用于企业的分布式环境中,实现了异构信息系统间的互操作和跨部门的数据处理,提高企业数据处理的效能,同时为企业异构信息系统集成提供了新的方法。  相似文献   
75.
76.
Tall oil, a by-product of the kraft process for pulping softwood, has been shown to have insecticidal properties. In the present study, the active principles in tall oil against the variegated cutworm,Peridroma saucia Hübner, were investigated. GC-MS analysis showed that abietic, dehydroabietic, and isopimaric acids were major resin acid components of crude tall oil and depitched tall oil. When crude tall oil samples of differing resin acid composition were incorporated into artificial diet at a concentration of 2.0% fresh weight, they suppressed larval growth by 45–60% compared to controls. This suppression was significantly (P0.05) correlated with the equivalent contents of abietic, dehydroabietic, isopimaric, and total resin acids. These results were also evident from a diet choice test, showing that the second-instar larvae obviously selected diets with low levels of resin acids when different diets were randomly arranged in a Petri dish. Bioassays with pure resin acids (abietic, dehydroabietic, and isopimaric acids) demonstrated that all individual chemicals have similar bioactivity against this insect. Comparison of the bioactivities of depitched tall oil and an equivalent mixture of pure resin acids in thePeridroma chronic growth bioassay indicated that pure resin acids and depitched tall oil share a common mode of action to this insect. This study confirms that resin acids are major active principles in tall oil against the variegated cutworm, but other chemicals likely also contribute to the bioactivity of tall oil.  相似文献   
77.
文章首先概述潇湘八景在日本传播发展的大致特点,之后重点针对铃木春信的《坐铺八景》这一组作品如何对应潇湘八景的每一个画题逐一做详细探讨,并深入阐释了春信作品如何将江户时代一个普遍的创作手法——“见立”创造性的运用于八景画题的独特特点。  相似文献   
78.
陈怡 《贵州化工》2003,28(6):21-22
介绍了合成型机动车制动液的生产和配方,讨论了物料组成对产品的影响。  相似文献   
79.
从提高学生职业能力理念出发,以高素质技能型人才培养为目标,教学改革和课程体系设计为先导,整合信息安全课程体系并进行优化,构建人才培养新方案,对教学内容进行有效探索,以期提高信息安全专业人才培养质量.  相似文献   
80.
An embossing strategy involving a hot station and a cold station for sequentially heating and cooling the embossing tool was investigated to reduce cycle times in hot embossing polymer microstructures. Experimental studies showed that aluminum stamps with a thickness of 1.4 mm can be rapidly heated from room temperature to 200°C in 3 s using contact heating against a hot station at 250°C. Microchannels and microlenses were successfully embossed onto high‐density polyethylene and acrylonitrile–butadiene–styrene substrates using a heating time less than 3 s and a total cycle time around 10 s. The two‐station embossing process for the microlens was also numerically studied. The simulated filling behavior agreed with the experimental observation and the predicted thermal and deformation history of the polymer offered a good explanation on the experimentally observed process characteristics. POLYM. ENG. SCI., 47:530–539, 2007. © 2007 Society of Plastics Engineers.  相似文献   
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