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71.
72.
自动化流动注射停流动力学分析仪的研制及其性能测试   总被引:1,自引:0,他引:1  
黄厚评  蔡汝秀 《分析化学》1995,23(5):551-553
本文研制了一套自动化流动注射停流动力学分析仪,该仪器由苹果Ⅱ型微机通过12位AD/DA卡,流动注射停流控制仪及用BASIC语言编制的软件控制泵的起动和停止,试样的输送和混合,数据采集和处理,结果显示和打印,通过以铁(Ⅲ)与硫氰酸盐的反应体系采用固定时间法和以钒(V)的胶束催化反庆体系采用安始速法的现场测试证明,该仪器具有结构简单,操作方便,恒温性能好,通用性强等特点。  相似文献   
73.
四氢键二聚体和分子组装   总被引:4,自引:0,他引:4  
介绍了最近几年新的四氢键有机二聚体研究的进展及其在分子自组装和分子聚 集体化学研究中的应用。  相似文献   
74.
脱蜡剂DF-1是一种含多种有机成分的碳氢化合物,经气相色谱-红外光谱联用分析后,确定了这些组分的组成与含量。  相似文献   
75.
Soluble fluorine containing poly(amide-imide)s, PAI(1-4), were synthesized from diimide-dicarboxylic acid, 2,2-bis[N-(4-carboxyphenyl)-phthalimide-1,4-yl]hexafluoropropane with various diamines by direct polycondensation in N-methyl-2-pyrrolidone (NMP) containing CaCl2 and using triphenyl phosphite and pyridine as condensing agents. The polymers were readily soluble in aprotic polar solvents such as NMP, N,N-dimethylacetamide, dimethyl sulfoxide and tetrahydrofuran. Their Langmuir monolayers were studied at the air/water interface. The monolayers were generally stable at the water surface and could be reproducibly transferred onto solid substrates to build up Langmuir-Blodgett (LB) multilayers. The LB mono- and multilayers were characterized by ultra-violet/visible spectroscopy (UV-Vis), surface plasmon resonance, atomic force microscopy.  相似文献   
76.
Silver halide (AgX) microcrystal was used as template to synthesize hollow polyelectrolyte capsules. These hollow capsules were characterized by laser light scattering (LLS) used to measure the size of the capsules in solution. The ratio of hydrodynamic radius (Rh) from dynamic LLS to the radius of gyration (Rg) from static LLS is almost unity, revealing that the entities are hollow in solution. The results suggest that the LLS method can be regarded as a good complement to the confocal laser scanning microscopy (CLSM) method for the characterization of small hollow capsules, and it possesses the advantage of not needing fluorescence labeling.  相似文献   
77.
Structural characteristics of pure silica gel (silica-xerogel, SiO2) and silica gel doped with some rare earth elements (REEs) such as, praseodymium Pr3+, and Europium Eu3+, Erbium Er3+ and Holmium Ho3+ ions, with different concentrations ranging from 1 up to 6%, in the form of monolith materials were prepared by sol-gel technique, Using tetra-ethoxysilane as precursor materials, which are of particular interest for sol-gel integrated optics applications. Some structural features of sol-gel derived monolith are analyzed, namely the structure of nano-particle momolith samples, based on X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR). We show that the XRD spectra of α-crystobalite are obtained for the pure samples at 1100°C and even by doping with the four REEs ions.  相似文献   
78.
New modifications of a contact heater are suggested for investigating thermal decomposition processes, as well as for determining kinetic characteristics of substances under conditions of intense heating to a fixed constant temperature.
Zusammenfassung Zur Untersuchung von thermischen Zersetzungsprozessen und der Bestimmung der Reaktionskinetik von Substanzen bei intensivem Erhitzen auf vorgegebene konstante Temperaturen wird eine neue Abart von Kontakterhitzern beschrieben.
  相似文献   
79.
A new element tracer technique has firstly been established to estimate the contributions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 32%―67% of total suspended particles (TSP), 10%―70% of fine particles (PM2.5), and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62% (38%―86%) of the total mineral aerosols in TSP, 69% (52%―90%) in PM10, and 76% (59%―93%) in PM2.5 in spring, and 69% (52%―83%), 79% (52%―93%), and 45% (7%―79%) in TSP, PM10, and PM2.5, respectively, in winter, while only ~20% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Beijing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.  相似文献   
80.
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