乙醛存在下氨基糖苷类抗生素的吸附伏安法研究

用悬汞电极，于Ｂｒｉｔｔｏｎ－Ｒｏｂｉｎｓｏｎ－ＣＨ３ＣＨＯ（ｐＨ９．５～１０．５）体系中研究了妥布霉素、丁胺卡那霉素等五种氨基糖苷类抗生素的吸附伏安行为，并讨论了其电极过程。认为该类抗生素结构上共有的伯、仲氨基与乙醛的衍生化反应产物，在一定电位下易吸附于电极表面。其不可逆还原峰的峰电位为－１．４５Ｖ（ｖｓ．ＳＣＥ）。在选定条件下，浓度在２．０×１０（－９）～２．５×１０（－７）ｇ／ｍＬ范围内均与还原峰峰电流呈良好的线性关系，检测限低至１．０×１０（－９）ｇ／ｍＬ。方法无需预处理即可用于软膏、尿样的测定，回收率在９０．３％～１１４％之间。     

Cr（Ⅵ）－PF－CDMAA显色反应及其应用

本文研究了铬（Ⅵ）－苯基荧光酮（ＰＦ）－＋六烷基二甲基氨基乙酸（ＣＤＭＡＡ）体系的分光光度特性和最适宜的显色条件。在两性表面活性剂ＣＤＭＡＡ存在下，于ｐＨ５．５～７．４的缓冲介质中铬（Ⅵ）与ｐＦ形成１：３的紫红色配合物，显色体系在５７６ｎｍ处有最大吸收，其摩尔吸光系数为１．４６×１０￣５Ｌ·ｍｏｌ￣（－１）＊ｃｍ￣（－１），铬（Ⅵ）含量在０～８．０μｇ／２５ｍＬ范围内符合比尔定律，变异系数为１．０３％～４．３３％。方法简便，灵敏度高，精密度和准确度好，在混合掩蔽剂存在下，可直接测定水中铬（Ⅵ）。     

6－硝基喹啉的单扫示波极谱分析

研究了６－硝基喹啉在滴汞电极上的电极过程并建立了它的单扫示波极谱测定法。在０．１０ｍｏｌ／ＬＮａＣｌ底液中，６－硝基喹啉的二阶导数阴极波峰电流ｉ”ｐ（Ｅ”ｐ＝－０．６６ＶｖｓＳＣＥ）与浓度在１．０×１０－７～２．５×１０－５ｍｏｌ／Ｌ范围内有良好线性关系，检出限为４．２×１０－８ｍｏｌ／Ｌ，ＲＳＤ＝１．７％（ｎ＝６）。此外还考察了多种人体内常见微量物质及表面活性剂对ｉ”ｐ的影响。     

以不对称长链叔胺为中性载体的PVC膜PH电极的研究

合成了一系列不对称长链叔胺类化合物作中性载体，研制成ＰＶＣ膜ｐＨ电极。其中（２－羟基苄基）二正癸胺、（β－氰乙基）ＬＡ－２、（２－羟基苄基）ＬＡ－２的电极线性范围分别为ｐＨ２．５～１２．５、ｐＨ２．５～１２．５、ｐＨ３．０～１２．５，斜率分别为５６．６±０．４ｍＶ／ｐＨ、５６．３±０．７ｍＶ／ｐＨ、５５．９±０．３ｍＶ／ｐＨ（３０℃）。这些ｐＨ电极内阻低，响应速度快，性能较稳定，可用于血清样中的ｐＨ值测量。此外，以（２－羟基辛基）ＬＡ－２为载体可制成流通式ＰＶＣ膜ｐＨ内电极型氨气敏电极。     

梨果及土壤中亚胺唑及其代谢物的气相色谱分析

介绍了杀菌剂亚胺唑及其代谢物ＩＢＣ－０１在梨果实及土壤样品内的提取、净化方法以及气相色谱的分析测定方法。保留时间：亚胺唑为３８．３６ｍｉｎ，ＩＢＣ－０１为１７．０１ｍｉｎ。变异系数：亚胺唑为０．４５％～１５．５３％，ＩＢＣ－０１为３．０３％～９．５２％。回收率：亚胺唑为８８．２８％～９８．５％，ＩＢＣ－０１为８４．９８％～９８．１３％。     

梨果及土壤中亚胺唑及其代谢物的气相色谱分析

 介绍了杀菌剂亚胺唑及其代谢物ＩＢＣ－０１在梨果实及土壤样品内的提取、净化方法以及气相色谱的分析测定方法。保留时间：亚胺唑为３８．３６ｍｉｎ，ＩＢＣ－０１为１７．０１ｍｉｎ。变异系数：亚胺唑为０．４５％～１５．５３％，ＩＢＣ－０１为３．０３％～９．５２％。回收率：亚胺唑为８８．２８％～９８．５％，ＩＢＣ－０１为８４．９８％～９８．１３％。     

黄金饰品中金含量的X－荧光能谱分析

应用Ｘ－荧光能谱分析（ＥＤ－ＸＲＦ）和新的定量分析软件测定了２６个黄金标样，研究了饰品形状的影响，不同方法，不同实验室测试结果的比对，表明在所选的工作条件下样品形状无明显影响。方法可靠、快速、简便，非破坏性，适于常规、批量分析。Ａｕ含量≥９９％时，分析误差≤０．１５％，精密度≤０．１％；金含量９０％～９９％时，分析误差和精密度≤０．２％；金含量７５％～９０％和＜７５％时，分析误差分别≤０．４％和０．５％，精密度均≤０．２％；Ａｇ、Ｃｕ和Ｚｎ的分析误差均≤０．５％，精密度≤０．２％。少标样基本参数法和多标样回归法的结果一致，在实用上有重要意义，十分有利于ＥＤ－ＸＲＦ的推广应用。     

自模式分辨红外光谱法在VC,VB2不分离测定中的应用

本文研究了自模式曲线分辨红外光谱法在维生素Ｃ－Ｂ２混合物体系中的应用，合理地估计了背景吸收。测定了不同配比维生素Ｃ－Ｂ２混合物组分，平均回收率分别为维生素Ｃ１０１．７±４．４％、维生素Ｂ２９９．４±３．５％，优于Ｂｅｃｋｍａｎ公司的标准曲线法：维生素Ｃ９３．０±２１．１％、维生素Ｂ２１０４．３±１５．２％。     

5-(对-羟基苯基):-5-苯基乙内酰脲的反相高效液相手性分离测定法

以β－ＣＤ为手性流动相添加剂、苯巴比妥为内标,于ＦＬＣ－Ｃ８反相柱上建立了鼠肝微粒体中５－（对－羟基苯基）－５－苯基乙内酰脲（ｐ－ＨＰＰＨ）外消旋体的拆分方法。测得ｐ－ＨＰＰＨ对映体的线性范围为０．５～１１０ｍｇ／Ｌ（ｒ＝０．９９９６）;最低检出量为５ｎｇ（Ｓ／Ｎ＝３）;Ｓ－ｐ－ＨＰＰＨ的回收率为９３．６％±２．８％,Ｒ－ｐ－ＨＰＰＨ的回收率为９４．７％±１．８％;日内和日间精密度ＲＳＤ值均小于２％。所建立的方法具有结果准确、操作方便等特点。     

蔬菜中低磷脂肪酸及乳酸的气相色谱分析

使用４’－胆甾烯氧羰基苯并－１５－冠－５（简称ＣＨ－Ｋ１５－Ｃ－５）气相色谱固定相建立了蔬菜中Ｃ１－Ｃ８脂肪酸及乳酸的定性、定量分析方法,测定的线性范围为０．１０～５０ｍｇ／Ｌ,ＲＳＤ≤３．７６％,回收率≥ ９７．０５％,该法快速、灵敏、准确,具有实用价值。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Copper catalyzed/mediated synthetic methodology for ebselen and related isoselenazolones

Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.     

Knoevenagel condensation catalyzed by novel Nmm-based ionic liquids in water

A series of novel N-methyl morpholine (Nmm) based ionic liquids with 1,2-propanediol group were synthesized and used as catalysts for Knoevenagel condensation at room temperature in water. Under the effect of the catalyst, various aldehydes or aliphatic ketones could react with a wide range of activated methylene compounds well, including malononitrile, alkyl cyanoacetate, cyanoacetamide, β-diketone, barbituric acid, 2-arylacetonitrile and thiazolidinedione. Furthermore, most of the products could be separated just by filtrating and washing with water. Additionally, the catalyst is recyclable and applicable for the large-scale synthesis.     

Construction of polyheterocyclic spirotetrahydrothiophene derivatives via sulfa-Michael/aldol cascade reaction

A series of polyheterocyclic spirotetrahydrothiophene derivatives were obtained in moderate to excellent yields via a catalyst-free sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 under mild conditions. We also present the first asymmetric sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 with moderate to good enantioselectivities catalyzed by readily available chiral phase-transfer catalysts (PTCs).