气相色谱-串联质谱法同时测定化妆品中的10种挥发性亚硝胺

建立了同时测定化妆品中10种挥发性亚硝胺(N-亚硝基二甲基胺,N-亚硝基二乙基胺、N-亚硝基二正丙基胺、N-亚硝基吗啉、N-亚硝基毗咯烷、N-亚硝基哌啶,N-亚硝基二正丁基胺、N-亚硝基二苯基胺、N-亚硝基二环己基胺及N-亚硝基二苄基胺)的气相色谱-串联质谱分析方法.膏霜、水剂、散粉、香波、唇膏等不同类型的化妆品样品分...     

萃取色谱分离-原子发射光谱测定超高纯氧化铥、氧化镱和氧化镥中痕量稀土杂质

用２－乙基己基膦酸单２－乙基己酯萃取色谱分离－原子发射光谱测定超高纯Ｔｍ２Ｏ３、Ｙｂ２Ｏ３、Ｌｕ２Ｏ３中痕量稀土杂质，可用于纯度为９９．９９９９％～９９．９９９９９％（不含非稀土杂质）Ｔｍ２Ｏ３、Ｙｂ２Ｏ３、Ｌｕ２Ｏ３的纯度分析，１４个稀土杂质的回收率在６７％～１３３％之间；相对标准偏差 ５．１％～２３．２％；分离周期 １０～１３ ｈ。     

衍生化气相色谱—质谱法测定氢化法制备的对氨基酚及其杂质

研究用衍生化气相色谱－质谱法 测定硝苯催化法生产的对氨基酚及其中杂质苯胺，４、４＇－二氨基二苯醚等。探讨了对氨基酚的萃取条件及色谱行为，选择了最佳衍生化方法。     

7,8—二甲基—10—（D—1—核糖醇基）—异咯嗪半合成中间体气相色谱分析

提出以三氟乙酸酐作为衍生化试剂,将核黄素半合成中间体Ｎ－（Ｄ）－脱氧核糖醇基－３,４－二甲苯胺（Ⅰ）及４,５－二甲基－Ｎ－（Ｄ）－脱氧核糖醇基－２－偶氮苯基苯胺（Ⅱ）转化为低沸点易汽化物质,采用以苯乙酮作为内标,测定中间体（Ⅰ）和（Ⅱ）纯度的气相色谱法。方法具有分析速度快、准确度高、重现性好等优点,方法回收率（Ⅰ）为９６．９％￣１０１．２％、（Ⅱ）为９９．４％￣１００．４％,相对标准偏差（Ⅰ）在４     

气相色谱法测定喷雾杀虫剂中的胺菊酯和氯菊酯

用SE-30毛细管柱、160~300℃程序升温、以邻苯二甲酸二环己酯为内标物,气相色谱法同时测定家用气雾杀虫剂中有效成分胺菊酯、氯菊酯的含量。胺菊酯、氯菊酯的平均回收率分别为94.0%、95.4%,相对标准偏差分别为2.23%、6.73%。     

桉树叶挥发油化学成分的研究

采用毛细管气相色谱-质谱（CGC-MS）联用技术对桉树叶挥发油的化学成分进行研究,经毛细管气相色谱分离出30个峰,共确认了其中21种成分,占总油量的97．57％。其主要成分是按油精、3,7,7-三甲基-二环[4．1．0]庚2-烯、α,α,4-三甲基-3-环已烯-1-甲醇、喇叭茶醇等。     

气相色谱法制备高纯苯

研究了应用气相色谱法制备的高纯苯，并对其制备条件的选择及结果进行了讨论，结果表明：采用此法制备的苯其纯度为９９．９７％，而美国ＥＰＡ苯标准物质纯度为９９．７％《     

萃取色谱分离—原子发射光谱测定超高纯氧化铥,氧化镱和氧化镥中痕…

用２－乙基己基膦酸单２乙基己酯萃取色说分离－原子发射光谱测定超高纯Ｔｍ２Ｏ３，Ｙｂ２Ｏ３，Ｌｕ２Ｏ３中痕量稀土杂质，可用于纯度为９９．９９９９％－９９．９９９９９％Ｔｍ２Ｏ３，Ｙｂ２Ｏ３，ｌＵ２ｏ３的纯分分析，１４个稀土杂质的回收率在６７％－１３３％之间；相对标准偏差５．１％－２３．２％，分离周期１０－１３ｈ。     

气相色谱-质谱法测定组合工艺己内酰胺产品中的微量关键杂质

己内酰胺（CPL）是重要的化工原料，CPL中即使存在微量的杂质都会对聚合产物的性能产生一定的影响，因此对聚合级CPL的纯度有很高的要求。该文对光密度值严重超标的组合工艺工业试验产品采用气相色谱-火焰离子化检测技术（GC/FID）、气相色谱-质谱（GC-MS）等手段进行了定性分析，确定该杂质的相对分子质量为188，分子式为C₁₂H₁₆N₂，环加双键数为6，为八氢吩嗪。结合组合工艺生产CPL所涉及化学反应的特点对八氢吩嗪的来源进行了理论推测，认为该杂质来源于Beckmann重排反应的副反应Neber重排，结构中含有较强的生色基团，对产品的光密度指标影响严重。因此，CPL生产过程中必须对八氢吩嗪的产生过程和生成浓度严格控制。     

茶条木挥发油的化学成分

采用毛细管气相色谱－质谱联用法对茶条木挥发油化学成分进行了研究,经毛细管普分离出１３４个峰,共确认了其中１０１种成分,所鉴定化合物的含量占全油的７８．０８％。用气相色谱面积归一化法测定了各成分的相对含量,其主要化学成分为二苯胺、棕榈酸甲酯、十六酸等。     

Furyl- and thienyl-silatranes and germatranes

We review our research on the synthesis and study of the physical and biological properties of furyl- and thienylgermatranes and -silatranes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 725–732, June, 1992.     

Review and patents and literature

The use of the insect cell/baculovirus expression system for producing recombinant proteins of bacterial, plant, insect, and mammalian origin has become widespread. The popularity of this eukaryotic expression system is due to many factors, including (1) potentially high protein expression levels, (2) ease and speed of genetic engineering, (3) ability to accommodate large DNA inserts, (4) protein processing similar to higher eukaryotic cells (e.g., mammalian cells), and (5) ease of insect cell growth (e.g., suspension growth). The following review of the literature discusses two engineering aspects of recombinant protein synthesis by insect cell cultures: bioreactor scale-up and insect cell line selection. Following this review patent abstracts and additional literature pertaining to expression of recombinant proteins in insect cell culture are listed.     

Ground- and excited-state aromaticity and antiaromaticity in benzene and cyclobutadiene

The aromaticity and antiaromaticity of the ground state (S 0), lowest triplet state (T 1), and first singlet excited state (S 1) of benzene, and the ground states (S 0), lowest triplet states (T 1), and the first and second singlet excited states (S 1 and S 2) of square and rectangular cyclobutadiene are assessed using various magnetic criteria including nucleus-independent chemical shifts (NICS), proton shieldings, and magnetic susceptibilities calculated using complete-active-space self-consistent field (CASSCF) wave functions constructed from gauge-including atomic orbitals (GIAOs). These magnetic criteria strongly suggest that, in contrast to the well-known aromaticity of the S 0 state of benzene, the T 1 and S 1 states of this molecule are antiaromatic. In square cyclobutadiene, which is shown to be considerably more antiaromatic than rectangular cyclobutadiene, the magnetic properties of the T 1 and S 1 states allow these to be classified as aromatic. According to the computed magnetic criteria, the T 1 state of rectangular cyclobutadiene is still aromatic, but the S 1 state is antiaromatic, just as the S 2 state of square cyclobutadiene; the S 2 state of rectangular cyclobutadiene is nonaromatic. The results demonstrate that the well-known "triplet aromaticity" of cyclic conjugated hydrocarbons represents a particular case of a broader concept of excited-state aromaticity and antiaromaticity. It is shown that while electronic excitation may lead to increased nuclear shieldings in certain low-lying electronic states, in general its main effect can be expected to be nuclear deshielding, which can be substantial for heavier nuclei.     

Hard and soft acids and bases: structure and process

Under investigation is the structure and process that gives rise to hard-soft behavior in simple anionic atomic bases. That for simple atomic bases the chemical hardness is expected to be the only extrinsic component of acid-base strength, has been substantiated in the current study. A thermochemically based operational scale of chemical hardness was used to identify the structure within anionic atomic bases that is responsible for chemical hardness. The base's responding electrons have been identified as the structure, and the relaxation that occurs during charge transfer has been identified as the process giving rise to hard-soft behavior. This is in contrast the commonly accepted explanations that attribute hard-soft behavior to varying degrees of electrostatic and covalent contributions to the acid-base interaction. The ability of the atomic ion's responding electrons to cause hard-soft behavior has been assessed by examining the correlation of the estimated relaxation energies of the responding electrons with the operational chemical hardness. It has been demonstrated that the responding electrons are able to give rise to hard-soft behavior in simple anionic bases.     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

Syntheses and structures of P-anilino-P-chalcogeno- and P-anilino-P-iminodiazasilaphosphetidines and their group 12 and 13 metal compounds

The P-anilino-P-chalcogeno(imino)diazasilaphosphetidines [Me(2)Si(mu-N(t)Bu)(2)P=E(NHPh)] (E = O (3), S (4), Se (5), N-p-tolyl (6)) were synthesized by oxidizing the P-anilinodiazasilaphosphetidine [Me(2)Si(N(t)Bu)(2)P(NHPh)] (2) with cumene hydroperoxide, sulfur, selenium, and p-tolyl azide, respectively. The lithium salt of 4 reacted with thallium monochloride to produce ([Me(2)Si(mu-N(t)Bu)(2)P=S(NPh)-kappaN-kappaS]Tl)(7), which features a two-coordinate thallium atom. Treatment of 4-6 with AlMe(3) gave the monoligand dimethylaluminum complexes ([Me(2)Si(mu-N(t)Bu)(2)P=E(NPh)-kappaN-kappaE]AlMe(2)) (E = S (8), Se (9), N-p-tolyl (10)), respectively. In these complexes the aluminum atom is tetrahedrally coordinated by one chelating ligand and two methyl groups, as a single-crystal X-ray analysis of 8 showed. A 2 equiv amount of 4-6 reacted with diethylzinc to produce the homoleptic diligand complexes ([Me(2)Si(mu-N(t)Bu)(2)P=E(NPh)-kappaN-kappaE](2)Zn)(E = S (11), Se (12), N-p-tolyl (13)). A crystal-structure analysis of 11 revealed a linear tetraspirocycle with a tetrahedrally coordinated, central zinc atom.