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1.
飞行时间二次离子质谱(TOF-SIMS)分析了难挥发的杂环新化合物咪唑啉硫氰酸盐及其三种衍生物, 确认出很强的氢离化及银离化准分子离子峰, 通过对各种衍生物谱图的对照分析, 确认出较强的含有结构特征的碎片离子峰, 并对该化合物在离子轰击下的裂解规律作了分析, 支持了对该新化合物结构的鉴定。  相似文献   

2.
Molecular complexes of different 1-, 2-, and 3-substituted indoles with chloranil have been studied by means of visible spectroscopy in chloroform; association constants of these complexes have been determined by Benesi Hildebrand method. The effect of solvant on association constants have also been studied in the case of the 2 methylindole-chloranil complex. This study has also lead to the determination of indole ionisation potentials by means of a Foster relation.  相似文献   

3.
Five organoazidosilanes have been synthesized by treating organo-chlorosilanes with sodium azide in tetrahydrofuran. Structure of these compounds have been proved and some physical properties have also been observed.  相似文献   

4.
Deoiled soya, an agricultural waste material, and bottom ash, a waste of power plants, have been successfully used for the removal and recovery of the hazardous water-soluble dye brilliant green from water. To remove the dye from water, batch adsorption studies have been carried out by observing the effects of pH, concentration, amounts of adsorbents, size of adsorbent particles, etc. Attempts have also been made to monitor the adsorption process through Langmuir, Freundlich, Tempkin, and D-R adsorption isotherm models. Relevant thermodynamic parameters have also been calculated from these models. The adsorption process has been found endothermic and feasible at all the temperatures. The kinetics of the adsorption was also recorded and indicates pseudo-second-order kinetics in both cases. Kinetic operations also reveal the involvement of a film diffusion mechanism for the deoiled soya adsorption at all the temperatures, while bottom ash undergoes through a particle diffusion mechanism at only 30 °C and at higher temperatures a film diffusion mechanism operates. Bulk removal of the dye has been carried out through column studies for both adsorbents. Attempts have also been made to recover the dye from exhausted columns by eluting sulfuric acid of pH 3.  相似文献   

5.
A study has been made of the cationic electropolymerization of trans-anethole initiated by a direct electron transfer mechanism at a Pt anode in 1,2-dichloroethane solution with tetrabutylammonium perchlorate as supporting electrolyte. The electrochemical behaviour of the system has been preliminarily investigated by voltammetry at rotating and stationary Pt electrode and also by chronoamperometry. The results are consistent with an ECE oxidation process of anethole with formation first of a radical cation and finally of a dication. Polymerization experiments by electrolysis at the oxidation potential of the monomer have been also carried out both under continuous electrolysis and with short initial pulses of current. The results have been analysed and some kinetic parameters of the system have been evaluated.  相似文献   

6.
Generally,thermotropicliquidcrystalsareconstructedoforganiccomPoundsofanisotropicshaPe.Inthesearchfornewmoleculardesignsformesogensoforiginalshapes,onecanroughlyfollowtwodirections.Thefirstideaistovarythenumberofalkylchainsgraftedaroundagivencore.Thesecondideaofshapemodificationconsistsintheformationofclustersofafewidenticalmesogens,generallyatwin.Accordingtothesetwoideas,manynewkindsofliquidcrystalshavebeensysthesized.Hexakis(4-(4'-alkoxy)biphenoxy)cyclotriphosphazeneswerethemostinteresting…  相似文献   

7.
The thermal behavior of synthetic schoenite (K2SO4·MgSO4·6H2)) during heating has been studied by thermal methods. The temperatures of dehydration and decomposition of schoenite have also been determined by DTA, TG and DSC. The thermal reaction equations and the X-ray power diffraction results of the products have been given and the corresponding kinetic parameters have also been obtained.  相似文献   

8.
近年来 ,一些重要的有机染料探针在生物大分子光度分析、荧光分析和共振光散射分析方面得到了日益广泛地应用[1,2 ] ,深入研究这些有机染料的结构和光谱特性 ,探讨这些有机染料与生物大分子之间的作用 ,对于筛选性能优良的分子光谱探针 ,设计更加灵敏简便的分子光谱检测器件 ,是现代分析化学十分重要的课题。本文测定了偶氮胂Ⅱ (Arsenazo)、铬黑T(EriochromeblackT)、铬蓝黑 (EriochromeblueblackR)等 3种化合物的荧光光谱 ,并用量子化学半经验方法AM1和PM3对3种化合物分子进行包括构型…  相似文献   

9.
Pt/HM、Pd/HM催化剂上CO氧化反应活性和动力学研究   总被引:1,自引:0,他引:1  
研究了Pt/HM、Pd/HM催化剂上CO氧化反应的活性,求出了各种催化剂的CO氧化反应动力学方程。考察了不同气氛下CO氧化活性的演变规律和V4+、Co2+离子对Pt、Pd的助催化作用,并用催化剂集团结构适应模型对以上结果作出了解释。  相似文献   

10.
Calix[n]arenes (n=4,6) with diphenylphosphinite groups appended to their lower rim have been synthesized by reaction first with base, followed by chlorodiphenylphosphine. The reaction has also been carried out with the partially methoxylated calix[n]arenes. Calix[6]arenes with phosphate groups selectively bridging adjacent pairs of oxygens have been synthesized by reaction first with base, followed by ethyl dichlorophosphate. Calix[n]arenes (n=4,6) with 2-aminoethyloxy groups appended to the lower rim have been synthesized both by the reduction of an amide or nitrile group. Calixarenes with 2-hydroxyethyloxy and 2-bromoxyethyloxy groups appended to the lower rim have also been prepared. A route to preparing calixarene-functionalized polymers by the alkylation of polyethyleneimine is also described.This paper is dedicated to the commemorative issue on the 50th anniversary of calixarenes.  相似文献   

11.
大气汽溶胶微粒子光学特性的研究   总被引:5,自引:0,他引:5  
根据Mie微粒子光散射理论计算了汽溶胶大气模型的光学特性,得到了汽溶胶的散射截面、吸收截面和消光截面以及红外波段散射强度分布,同时计算了汽溶胶大气的发射率光谱,为研究大气红外传输提供了计算方法。  相似文献   

12.
The aggregation equilibria of the commercial extractant Cyanex 302 in toluene have been studied by vapor pressure osmometry (VPO) at different temperatures. The experimental data, treated both graphically and numerically by means of the CPMIN program, can be explained by assuming the formation of a dimer species of the active component bis(2,4,4-trimethylpentyl)thiophosphinic acid for which the aggregation constants have been determined at 28, 40 and 50°C. The influence of other components of the commercial reagent in the aggregation equilibria have also been considered. The interaction between Cyanex 302 and the non-ionic surfactant Span 80 in toluene has also been investigated by VPO and the experimental results interpreted by the formation of mixed species between both reagents.  相似文献   

13.
对聚炔体系的非线性光学性质用从头算方法和半经验方法与有限场方法结合进行了计算并对这两种方法的结果进行了系统的比较。用最小二乘方法拟合得到了其非线性光学性质与聚合物链长的函数关系, 并通过外推得到了平均每个单孢非线性光学性质的极限值。  相似文献   

14.
Various 4-aryloxymethylcoumarins have been obtained by the r.t. allylic substitution with formylphenols. These have been further reacted with o-aminothiophenol resulting in the formation of a benzothiazole skeleton. These compounds have been synthesised with a view to study their potential as microbial growth inhibitors. Comparative studies on the spectral and antimicrobial activities have also been carried out.  相似文献   

15.
一些缩氨硫脲及其衍生物对结核、麻风、风湿、疟疾、天花、真菌和某些肿瘤有一定的药理活性。缩氨硫脲的真菌活性是由于它的配位原子在生物体的新陈代谢中和真菌所需的金属离子螯合。缩氨硫脲具有与氨基酸、肽、蛋白质、酶、核糖核酸等生物配体相同的配位原子、被看作研究生物配体和痕量金属离子配位的优良模型。因为聚乙二醇醚链上的氧原子能与金属离子配位,所以在缩氨硫脲分子中连接上聚乙二醇醚链,增加缩氨硫脲分子中的配位原子种类和数目,也许能够增强螯合剂的配位能力,扩展其与金属离子的螯合围范。为此,我们将缩乙二醇二氯化物和苯环上带酰基的苯酚反应,制成化合物1_(a-h),然后再与硫代氨基脲缩合,得到醚链桥接的芳香醛缩氨硫脲2_(a-g)。它们的合成路线和主要结构如下:  相似文献   

16.
A variety of nearly monodisperse semiconductor nanocrystals, such as CdS, ZnS, and ZnS:Mn, with controllable aspect ratios have been successfully prepared through a facile synthetic process. These as-prepared nanocrystals were obtained from the reactions between metal ions and thioacetamide by employing octadecylamine or oleylamine as the surfactants. The effects of reaction temperature and time, ratios of thioacetamide to inorganic precursors, and the reactant content on the size and crystal purity of the nanorods, have been systematically investigated. The optical properties and the formation mechanism of the nanorods have also been discussed. For the next biolabel applications, these hydrophobic nanocrystals have also been transferred into hydrophilic colloidal spheres by means of an emulsion-based bottom-up self-assembly approach.  相似文献   

17.
Derivatives of derrusnin and also its benzodioxane and benzodioxepane analogs have been synthesized. The structures of the compounds obtained have been confirmed by spectral studies.  相似文献   

18.
The hydroboration reactions of acetaldehyde and acetone have been investigated by the MNDO method. The reactions have been shown to be twostep reactions involving an intermediate adduct. This adduct subsequently undergoes hydrogen rearrangement. The hydroboration reactions of acetaldehyde and acetone have been compared with the corresponding reaction of formaldehyde. The charge transfer effects accompanying these reactions have also been discussed.  相似文献   

19.
分别用空气氧化和H2O2氧化沉淀法制得了纳米级α-Fe2O3气陶瓷粉料,对粉体进行了XRD物相分析及晶粒度、晶格畸变率的测定,以TEM观察其形貌并测得了平均粒径,采用迎头色谱法测定其比表面积。结果对照表明,H2O2氧化法制得的粉体粒度更小,而且该法还具有不引入有害杂质,便于共沉掺杂等优点,是更有发展前途的α-Fe2O3基气敏陶瓷粉料制备方法。  相似文献   

20.
The present invention is to provide a novel benzothiazole-type polymerizable dye containing a urethane bond. A series of monomeric dyes have been prepared by diazotization of various 2-aminobenzothiiazole and coupled with Resorcinol. The polymeric dyes have been prepared by polycondensation of monomeric dyes with hexamethylene diisocyanate (HMDI), and they are characterized by molecular weight, non-aqueous conductometric titration, thermogravimetry analysis, IR, visible spectroscopy, and elemental analysis. The monomeric dyes have also been characterized by elemental analysis and IR spectra. The purity of all the dyes have been checked by thin layer chromatography, and their dyeing performance on nylon and polyester was assessed. The dyeing on polyester fiber had yellow, orange and pink shades with moderate to good light and wash fastness. Polymerizations of monomeric dyes with HMDI on dyed polyester have also been carried out. Color and dyeability of the polymeric dyes have been discussed by comparing them with their corresponding monomeric dyes. The percentage dye bath exhaustion and fixation on fiber have been found to be from good to very good. The dyeing of monomeric dyes showed very good color fastness properties, and their corresponding polymeric dyes showed excellent fastness to light, washing, perspiration, solvent resistance, and sublimation.  相似文献   

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