水玻璃再生砂中Na2O残留量的分析方法

水玻璃系再生砂质量与其残留Na2O的数量有较大关系.经过对几种检测水玻璃类再生砂中残留Na2O方法的研究,阐明一种非常简便的方法--盐酸滴定法.实践证明,该方法检测结果稳定、容易掌握、检测耗时少、成本低.     

水玻璃砂的再生

介绍了水玻璃旧砂湿法、干法和热法的再生原理,并简要说明了其应用情况.通过阐述人们对水玻璃硬化机理的认识,说明了水玻璃旧砂化学再生的基本原理,并对近年来水玻璃旧砂化学再生方面的研究及应用情况进行了总结概括.     

TiN/SiNx submicronic multilayer coatings obtained by chemical vapor deposition in a fluidized bed reactor at atmospheric pressure (AP/FBR-CVD)

TiN/SiN_x multilayer coatings were deposited on stainless steel by Chemical Vapor Deposition in a Fluidized Bed Reactor at Atmospheric Pressure (AP/FBR-CVD) by reaction of TiCl₄ and SiCl₄ with NH₃ at 850 °C. Due to the immiscibility of crystalline TiN and amorphous SiN_x, interdiffusion between layers is avoided even at the high working temperature. The thickness of the individual layer was in the nanometer range. Coatings were characterized by means of SEM, TEM, GD-OES, SIMS, XRD and nanoindentation. A mechanism for the growth rate and diffusion of Ti and Si into the steel is discussed.     

聚乙二醇化重组人生长激素的性质及活性

目的　研究聚乙二醇化重组人生长激素的性质及活性。方法　通过分子筛高效液相 (SizeexclusionHPLC)、毛细管等电聚焦 (CIEF)、圆二色谱 (CD)以及荧光光谱等方法检测单聚PEG- GH的纯度、等电点、二级结构以及分子构象 ;采用妊娠兔肝细胞放射受体分析法 (RRA)检测单聚PEG GH的体外受体亲和力 ,采用未成年去垂体大鼠体重增加法检测体内生物活性。结果　分子筛高效液相图谱上仅出现一个峰 ,表明样品纯度很高 ,等电点范围为 5 .1～ 5 .2 ,与未修饰的rhGH的等电点相一致 ;CD谱与荧光光谱均表明单个mPEG ALD的修饰对rhGH的二级结构以及分子构象没有明显影响 ;与未修饰的rhGH相比 ,单聚PEG GH体外受体亲和力明显降低 ;但体内作用时间更长 ,且更加有效。结论　此结果为进一步研究和开发长效重组人生长激素提供了理论依据。     

GRAPHICAL PROCEDURE FOR REACTIVE DISTILLATION SYSTEMS

In this paper we analyze a ternary reactive distillation system, where an equilibrium chemical reaction occurs in the liquid phase. By using a set of transformed variables proposed by Barbosa el al. (1988b) and well known graphical procedures for non-reactive systems; the minimum reflux ratio, minimum number of equilibrium stages, mass and energy balances for a reactive column and flash can be easily obtained. The procedures developed in this paper are applied to ISOBUTYLENE-METHANOL-MTBE system.

The main objective in developing this model is to obtain, as much as possible, rigorous information for the analysis of one reactive distillation column in a Process Simulator with capability of handling this type of new operation.     

兰香草挥发油化学成分的研究

采用常压水蒸气蒸馏法提取了兰香草挥发油,得油率为 0.35 ~ 0.52%。其相对密度(20℃/4℃)0.9980 ~0.9900,折射率(20℃)1.4608,比旋光度+0.51°;酸值1.5。并用毛细管气相色谱、红外光谱、核磁共振谱和色-质联机等对该挥发油进行了系统的成分分析。在分出的112个色谱峰中,共鉴定出 71 个化合物,占挥发油总量的 94.6%。其主要成分为芳樟醇、紫苏醇、香芹酮、荠苎烯、4-甲基-6-庚烯-3-酮、葎草烯、马鞭草烯酮、左旋松香芹酮、2-壬烯-4-炔等。     

非均相固定化酶促反应中“抗激发互交作用”的解析分析与定量计算

通过理论推导证明：在外扩散与化学抑制共存的非均相固定化酶促反应中，总有效系数η为外扩散有效系数ηｄｉｆ和化学抑制有效系数ηｃｈ的乘积，并且分别小于相应的ηｄｉｆ和ηｃｈ；从数学上解释了外扩散抑制和一般性化学抑制间所存在的“抗激发互交作用”。利用所得公式计算表明：底物浓度对外扩散与竞争性、非竞争性和反竞争性等不同化学抑制共存的非均相固定化酶促反应有明显不同的影响；扩散抑制均显著地影响非均相固定化酶促反应，使得反应体系的总有效系数随抑制作用的增加而明显减小，从而对这类反应有了更进一步的认识     

The influence of demineralisation and ammoxidation on the adsorption properties of an activated carbon prepared from a Polish lignite

The preparation of cheap nitrogen-enriched materials with large adsorptive capacities and selectivity towards volatile organic compounds remains a challenge. Ammoxidation has been used to prepare nitrogen-enriched activated carbons using a demineralised Polish lignite. The lignite samples were demineralised by two different methods before nitrogen-enrichment by ammoxidation and physical activation in steam. The surface chemistry was investigated by elemental analysis, Boehm titration, infrared and XPS spectroscopies and adsorptive properties by a linear solvation energy relationship approach. Results show a quasi-total demineralisation and a higher reactivity towards nitrogen for the demineralised samples. The BET surface is also higher than for the non-demineralised lignite. Active carbons previously ammoxidated and demineralised are more interesting in terms of selective removal of gaseous pollutants.     

Growth of sculptured polymer submicronwire assemblies by vapor deposition

We have grown helical nanowire assemblies of parylene C, thereby demonstrating that polymeric sculptured thin films (STFs) can be fabricated by a combination of physical and chemical vapor deposition processes. The deposition method is explained in detail and electron micrographs of 200-400 nm size sculptured thin film of parylene are given. The shapes of the submicron and nanowire assemblies can be engineered so that the polymeric STF acts as a template for preferential attachment of biomolecules.