共振瑞利散射法测定硫氰酸盐—碱性三苯甲烷染料体系中？…

研究了钼（Ｖ）与硫氰酸盐和结晶紫，乙基紫，孔雀石绿，亮绿及碘绿等５种碱性三苯甲烷染料形成离子缔合配合物的共振瑞利散射光谱，考察了它们的光谱特征，影响因素和适宜的反应条件，确定了共振瑞利散射强度与钼（Ｖ）浓度之间的关系，方法灵敏度高，不同体系对钼的检出限在２．１～１２．０μｇ／Ｌ之间，提出了用共振瑞利散射测定钼的新分析方法，将其用于钢铁中痕量钼的测定获得满意的结果。     

溴代十六烷基三甲基铵敏化亮绿—脱氧核糖酸作用的共振光散射增强研究

首次报道在表面活性剂存在下阳离子染料与脱氧核糖核酸（DNA）作用所导致的共振光散射增强（RLSE）。在pH10．4－11．8和离子强度低于0．050mol／L的条件下,亮绿（BG）与DNA作用产生398．0和467．2nm的特征RLSE信号,而溴代十六烷基三甲基铵（CTMAB）进一步敏化该RLSE信号。受CTMAB敏化的RLSE信号与0－1．2mg/L的ctDNA和fsDNA呈正比,检测限低于5mg/L。方法成功应用于合成样中NDA的测定。     

Pittcon 2005国际分析会议(三)暨第10次关于痕量金属形态的分析方法论进展国际研讨会

2005年Pittcon会议续报如下：生物材料表面和界面的化学成像技术组报告有：（1）DG Castner，应用x射线的生物和有机物表面的成像技术——光发射电子显微术和x射线光电子能谱技术的研究；（2）N Winograd，应用聚束表面电离质谱技术进行单个生物细胞的三维化学成像的前景；（3）R MCorn，供蛋白质和脱氧核糖核酸微阵列用的酶法表面等离子体激元共振成像技术；（4）B Hagenhoff，生物材料表面和界面的化学成像技术；（5）PS Weiss，膜-细胞骨架和膜-表面相互作用的物理模型。     

铝离子与脱氧核糖核酸作用的共振光散射研究

在PH2．21的酸性介质中，Al^3 与脱氧核糖核酸（DNA）发生静电作用产生以291．0nm为特征峰的共振光散射（RLS）增强光谱，即Al^3 主要与DNA分子表面的磷酸根结合，但DNA热变性将导致Al^3 与DNA的碱基结合，使光散射信号降低，在291．0nm处的共振光散射（RLS）强度与DNA的浓度呈线性关系，据此建立了用共振光散射测量痕量DNA的新方法，方法的检出限为ng级，用于合成样分析，回收率在91．6％－105．0％。     

催化动力学光度法测定水中微量锰

１引言研究了锰（Ⅱ）催化亮绿ＳＦ褪色反应的动力学特性。在ＮａＡｃ－ＨＡｃ介质中，锰（Ⅱ）对高碘酸钾氧化该试剂的褪色反应具有强烈催化作用，其褪色反应速率与锰（Ⅱ）的浓度在一定范围内呈良好的线性关系。详细研究了亮绿ＳＦ催化动力学光度法测定微量锰（Ⅱ）的条件，建立了测定微量锰（Ⅱ）的新方法。有关文献中催化动力学光度法测定锰（Ⅱ）的检出限大多为１０－１０ｇ／ｍＬ，本方法的检出限为６．０×１０－１１ｇ／ｍＬ，选择性较好，方法相对标准偏差２．５％，用于测定水样中的锰，结果满意。２实验部分２．１主要试剂和仪器…     

水溶性游离碱阳离子卟啉与核酸作用的光谱研究

研究了ｍｅｓｏ－四（对－三甲基氨基苯基）卟啉（ＴＡＰＰ）和ｍｅｓｏ－四（对－甲基吡啶基）卟啉（ＴＭｐｙＰ－４）与核酸作用的电子吸收光谱、荧光光谱和共振光散射光谱的特性，电子吸收和荧光光谱研究表明，这两个水溶性阳离子卟啉与核酸的摩尔比（Ｒ）大于０．２５时，核酸对卟啉的Ｓｏｒｅｔ带有减色效应和荧光猝灭效应；当Ｒ〈０．２５时，核酸与卟啉作用形成新的荧光复合物，共振光散射光谱研究表明，核酸使ＴＡＰＰ的共振     

阳离子表面活性剂与四苯硼钠反应的共振瑞利散射光谱及其分析应用

研究了在HAc-NaAc缓冲溶液中5种阳离子表面活性剂（CS）与四苯硼钠（NaTPB）反应的共振瑞利散射（RRS）光谱，考察了其光谱特征、影响因素、适宜的反应条件和共存物质的影响。发现5种CS与NaTPB形成离子缔合物时，均使RRS强度显著增强，并具有相似的RRS光谱特征，最大散射波长均位于284nm左右。在一定范围内，cs的浓度与散射强度成正比。方法简便，快速，灵敏度高，并具有较好的选择性，对于不同CS检出限在2．23～5．62μg／L；用于水样分析，结果令人满意。     

表面等离子体子共振生物传感器用于乙肝表面抗原的测定

运用自行研制的表面等离子体子共振（SPR）生物传感器，采用自组装成膜技 术并以戊二醛作偶联剂，在传感片表面修饰HBsAg单克隆抗体，将其用于乙肝表面 抗原（HBsAg)的检测。实验结果表明SPR生物传感器对HBsAg的检出限为0.06ng/mL 。与传统的酶联免疫吸附试验（ELISA）相比，SPR生物传感器的检出灵敏度明显高 于ELISA法。用该SPR生物传感器对HBsAg质控血清与纯化的HBsAg溶液进行比较检测 ，结果表明该SPR生物传感器对HBsAg具有好的特异选择性。     

表面等离子体共振光谱技术与电化学方法联用及其应用

表面等离子体共振（Surface Plasmon Resonance,SPR）技术是利用金属薄膜光学耦合产生的物理光学现象建立的一种非常灵敏的光学分析手段. 近年发展的电化学表面等离子体共振（Electrochemical Surface Plasmon Resonance,EC-SPR）是将时间分辨表面等离子体共振光谱技术与电化学方法联用的一种新技术. 本文介绍了SPR和EC-SPR的基本原理,并重点阐述了时间分辨SPR光谱技术与电化学方法联用及应用,该技术已广泛地应用于反应动态过程研究、生物化学传感器、电极/溶液界面的表征、动力学常数的测定以及生物分子相互作用等领域.     

Au/Ag复合纳米笼在表面增强拉曼光谱中的应用

表面增强拉曼光谱（SERS）技术是一种基于贵金属纳米结构基底对被检测物进行高灵敏度检测的一种方法.具有特殊纳米结构的贵金属表面受到激光的照射时，金属表面的自由电子会受到极大的振荡，当入射光频率与振荡频率相近时，则会发生表面等离子体共振现象（SPR），使金属表面的局域电场强度极大增强，入射光强度和散射光强度都得到成倍的放大，从而使吸附在贵金属纳米结构表面的分子的拉曼散射信号得到有效的增强.使用NaBH₄还原-酸刻蚀模板法，制备了八面体Au/Ag复合纳米笼，其形貌规整，尺寸均匀约为600 nm，无Cu₂O模板的残留，Au元素均匀负载在Ag纳米笼上，质量分数约为16.8%；Au/Ag复合纳米笼的紫外可见吸收峰相对于Ag纳米笼发生了红移，更重要的是，Au和Ag元素协同赋予了复合纳米笼超高的SERS灵敏度和重复性，Au/Ag复合纳米笼实现了对罗丹明6G的痕量检测（5×10^-14 mol/L），通过时域有限差分法（FDTD）模拟证实：这主要归因于等离子共振作用产生的高电磁场强度；此外，Au元素的加入使Au/Ag复合纳米笼具有优异的抗氧化性和化学稳定性，即使在1%的H₂O₂溶液中浸泡3 h，仍然能够保持优异的SERS性能.八面体Au/Ag复合纳米笼有望成为一种具有应用前景的高灵敏度、高稳定性的SERS基底.     

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%.     

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.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

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.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.