火场中有机高分子材料对汽油燃烧残留物鉴定干扰的研究进展

综述了纤维材料、塑料和橡胶等3类有机高分子材料对汽油燃烧残留物鉴定干扰的研究进展,重点介绍火场中这3种有机高分子材料热解或燃烧产物中产生的干扰性特征组分以及排除此种干扰的方法(引用文献54篇).     

取代的二氧杂癸二烯二酮的合成和鉴定

在由β二酮与1,2-二溴-乙烷分别合成相应的三员环化合物的过程中,意外地获得了另一类十分有趣的化合物:1,10-二苯基-3,8-二甲基-4,7-二氧杂-2,8-癸二烯-1,10-二酮和1,3,8,10-四甲基-4,7-二氧杂-2,8癸二烯-1,10-二酮.此类化合物具有十分特殊的结构,其中含有多个活性官能团,从而有可能成为一类重要的有机合成原料.     

对苯二亚甲基联二高三蝶烯的合成

报道了一种从蒽酮出发制备对苯二亚甲基联二高三蝶烯的合成方法. 以蒽酮为原料, 经缩合、加氢还原以及Williamson烷基化反应得到一系列的联二蒽酮衍生物10e, 12f～12h. 受其10位取代基等因素的影响, 12f～12g在NaBH₄还原和酸催化条件下发生选择性的1,7-跨环脱水成环反应, 高产率地得到了联二高三蝶烯14f～14g. 在相同条件下, 10e和12h却发生了1,4-脱水和重排反应生成了联二蒽衍生物15i～15j, 而不是预期的螺环类联二高三蝶烯产物16i～16j. 另外, 在制备过程中还得到了一些结构新颖的副产物如蒽醇过氧化物5a～5c, 以及蒽醚酮类衍生物11a, 13a等.     

昆虫性信息素共轭二烯的合成进展

许多昆虫性信息素具有共轭二烯的结构,它们的双键位置和几何构型是决定其生物活性的重要因素。立体选择性和区域选择性地合成共轭二烯是有机合成中十分有意义的研究课题。文章综述了昆虫性信息素共轭二烯的合成进展。     

二苯骈环辛二烯类木酚素的化学合成进展

本文从合成战略的角度概述具有多种生理活性的二苯骈环辛二烯类木酚素近年来在化学合成方面的研究进展,特别是近年来合成战略的实施和新非酚氧化偶合试剂的运用。     

类硅烯H_2SiLiF二聚反应的理论研究

从理论上研究了类硅烯H2SiLiF的三元环构型为反应物的二聚反应2H2SiLiF→H2SiSiH2+2LiF。在MP2/6-31G(d)和QCISD(T)/6-31G(d)水平下的计算结果表明,H2SiLiF的二聚反应经过两个阶段:阶段I,先形成过渡态TS1,经过中间体Int,形成一个四元环的中间产物Pro1,同时消去一个LiF;阶段Ⅱ,Pro1继续反应形成过渡态TS2,进而解离生成产物H2SiSiH2和一个LiF。从能量上看,反应易停留在中间产物阶段。本文对反应物、过渡态以及产物的结构、稳定性等方面进行了讨论,很好解释了实验结果。     

烯二炔类抗肿瘤抗生素的合成进展

综述了四个天然产和的中分离的烯二炔类抗肿瘤抗生素的合成进展.它们是:Calicheamicin,Esperamicin,Neocarcinostatin chromophore和dynemicin,此外还综述了若干人工设计的烯二炔类结构化合物的合成进展     

光致变色全氟环戊烯类二芳烯化合物的合成及其性质研究

合成了两种新的二芳基乙烯类光致变色化合物1,2 双(2 甲基5 (4 乙氧基苯基)噻吩3 基)全氟环戊烯(1a)和1,2 双(2 甲基5 (对氟苯基)噻吩3 基)全氟环戊烯(2a),并且研究了其在不同溶剂和浓度中的UV Vis光谱、荧光性质和光致变色反应动力学特征.实验结果表明,化合物1a和2a具有良好的光致变色性质和较强的荧光;光致变色闭环反应为零级反应,开环反应为一级反应.     

基于二芳炔硫醚的2,6-二芳基-1,4-二噻烯的合成

描述了一种基于二芳炔硫醚(Ar—C≡C—S—C≡C—Ar)底物合成2,6-二芳基-1,4-二噻烯的方法.将二芳炔硫醚和Na2S·9H2O在C2H5OH/C2H5ONa体系中回流反应,以80%~96%的产率合成了一系列2,6-二芳基-1,4-二噻烯化合物.该方法反应条件温和、产率高并且表现出很好的选择性.反应机理涉及硫负离子对底物分子的两个C≡C键的选择性亲核加成,即硫负离子(包括S2-和中间体B硫负离子)总是选择性地加到芳基一侧的炔碳上形成1,4-二噻烯.对化合物1a进行了X线晶体结构解析.分子中的六元杂环呈"船式"构型.C(1)—C(2)和C(1A)—C(2A)具有典型的双键性质,S(1)—C(2)和S(2)—C(1)的键长数则比一般C—S单键稍短,显示硫原子上的孤对电子与C(1)=C(2)双键上的π电子存在一定程度的共轭作用.1a的晶体学参数:属正交晶系,Pnma空间群,a=10.1330(11),b=27.318(3),c=5.5402(6),α=90.00°,β=90.00°,γ=90.00°,V=1533.6(3)3,Z=4,ρcalcd=1.422 g/cm3.最终偏离因子R=0.038,Rw=0.102。     

青蒿二烯功能模块与酵母底盘的适配性

设计构建人工酿酒酵母细胞合成青蒿二烯的关键是使外源功能模块与底盘细胞适配,本文通过对外源功能模块中的载体、蛋白表达和启动子进行优化,以提高功能模块与底盘细胞的适配性. 使用着丝粒载体和附加型载体构建了2种青蒿二烯功能模块,在过表达甲羟戊酸（MEV）途径中关键基因（截短的3-羟基-3-甲基戊二酰辅酶A还原酶基因tHMGR及法尼基焦磷酸合酶基因ERG20）的2种酵母底盘中进行适配,得到适配性较好的人工合成细胞,其产量为11.2 mg/L;将青蒿二烯合酶基因（ADS）与ERG20进行融合构建融合蛋白功能模块,在选定底盘中适配性进一步提高,青蒿二烯的产量提升至17.5 mg/L;采用不同强度的启动子（TDH3p,TEF1p和PGK1p）对融合蛋白功能模块进行调控,最终得到功能模块与底盘间适配关系更好的人工合成细胞,其产量提升到71.8 mg/L.     

Chemical Composition of Nanoglobular Material on the Surface of Rubber Regenerate Prepared by Explosive Circulation Technology

The rubber crumbs produced by the explosive circular destruction of worn-out automobile tires were studied. The crumbs showed high hydrophilicity. Their surface was analyzed by X-ray photoelectron spectroscopy. C, O, S, Zn, and Si were detected on the surface, and their chemical states were determined. The same chemical composition in the rubber crumb surface prepared by the explosive grinding of tires, as well as nanoglobules covering the crumb surface, was revealed. The appearance of polar groups on the crumb surface explains its high hydrophilicity and good compatibility with polymer matrices.     

Hydrothermal Liquefaction of Arthrospira platensis for Bio-Oil Production and Study of Chemical Composition for Bio-Oil and Its Gasoline Fraction

Russian Journal of Applied Chemistry - The fractional and chemical composition of bio-oil and its gasoline fraction, obtained by hydrothermal liquefaction of Arthrospira platensis biomass, was...     

七里香蔷薇精油化学成分的研究

用毛细管气相色谱法分离七里香蔷薇花精油中的各种组份，用GC/MS和Kvoats指数对各种组份进行鉴定，共定性出31种化合物，其中以正十一烷、正十九烷、十九烷-1、正二十三烷为主要成分。     

Classification of Polish Natural Bee Honeys Based on Their Chemical Composition

The targeted quantitative NMR (qNMR) approach is a powerful analytical tool, which can be applied to classify and/or determine the authenticity of honey samples. In our study, this technique was used to determine the chemical profiles of different types of Polish honey samples, featured by variable contents of main sugars, free amino acids, and 5-(hydroxymethyl)furfural. One-way analysis of variance (ANOVA) was performed on concentrations of selected compounds to determine significant differences in their levels between all types of honey. For pattern recognition, principal component analysis (PCA) was conducted and good separations between all honey samples were obtained. The results of present studies allow the differentiation of honey samples based on the content of sucrose, glucose, and fructose, as well as amino acids such as tyrosine, phenylalanine, proline, and alanine. Our results indicated that the combination of qNMR with chemometric analysis may serve as a supplementary tool in specifying honeys.     

空气-乙炔火焰原子吸收测定铬时与浓度有关的化学干扰的研究——Ⅰ、铁、钴对铬的干扰

本文较详细地研究了在Fe、Co基体中测定铬时出现的与浓度有关的化学干扰,铬的价态对干扰的影响,并讨论了干扰的机理及克服干扰的办法。     

Chemical Composition and Structure of Thin Films Produced by Chemical Vapor Deposition

This paper reports results from studies of the chemical composition and structure of semiconducting, dielectric, and metallic films produced from molecular precursors by the chemical vapor deposition method. A study was made of films of zinc sulfides, mixed copper, cadmium, and zinc sulfides, boron nitride, carbonitride, silicon carbonitride, and iridium films. It is shown that the use of metal compounds with different ligands (zinc and manganese) enables production of zinc sulfide films in which manganese ions are uniformly incorporated into the zinc sulfide crystal lattice to substitute zinc at the lattice sites. For the films of simple and mixed cadmium, copper, and zinc sulfides, the film structure depends on the type of substrate. The thin layers of mixed cadmium and zinc sulfides are asubstitution solution with a hexagonal structure. The thin layers of boron nitride produced from borazine exhibit a nanocrystalline structure and are a mixture of cubic and hexagonal phases. Composite layers were produced from alkylamine boranes and their mixtures with ammonia. Depending on synthesis conditions, the layers are mixtures of hexagonal boron nitride, carbide, and carbonitride or pure boron nitride. Using silyl derivatives of asymmetric dimethylhydrazine containing Si—N and C—N bonds in the starting molecule, we produced silicon carbonitride films whose crystal habit belongs to a tetragonal structure with lattice parameters a = 9.6 and c = 6.4 . The iridium films obtained by thermal decomposition of iridium trisacetylacetonate(III) on quartz substrates in the presence of hydrogen have a polycrystalline structure with crystallite sizes of 50 to 500 . A method for determining grainsize composition was proposed, and grain shapes for the iridium films were analyzed. The influence of substrate temperature on the internal microstructure and growth of the iridium films is demonstrated. At the iridium–substrate interface, a transition layer forms, whose composition depends on the substrate material and deposition conditions.     

微波提取对挥发油化学成分的影响

采用无溶剂微波辅助提取与微波水蒸气蒸馏法提取薄荷叶和花椒挥发油,气相色谱-质谱(GC-MS)分析挥发油化学成分,与传统的水蒸气蒸馏对比,考察了微波对挥发油化学成分的影响.结果表明,微波促使薄荷叶挥发油中的薄荷醇氧化,转变为长叶薄荷酮和少量的薄荷呋喃酮.花椒挥发油中的按油素等化合物受质子的催化,在长时间温度较高的提取条件...     

橡胶基多效协同自修复防水复合材料的研究

制备了环氧树脂改性高吸水纤维,随后将改性纤维与天然橡胶通过混、流延、压延、硫化等工艺制备了环境友好型三层复合自修复防水材料,通过SEM、FT-IR、TY-8000万能材料试验机、BTS-001电动不透水仪等考察了自修复防水材料的微观结构、机械性能、抗氧化性能、自修复性能及防渗透性能等。结果表明,高吸水纤维有助于提高其拉伸强度,最大拉伸强度为1.83MPa,断裂伸长率达到700%以上。防水材料完全切断,自修复24h后,其切口部分无可见痕迹,裂口完全愈合,且24h内无水滴渗漏。自修复48h后拉伸强度可达原始材料的2.36倍,断裂伸长率达到80%左右。