铅基磷酸铅化学修饰电极的研究

本研制了铅基磷酸铅化学饰电极，并研究了该ＣＭＥ的性能。实验发现，该ＣＭＥ是一种磷酸根离子敏感电极。电极对磷酸盐有类能斯特响应，在ＰＨ４．０和６．０下，其线性范围分别为１×１０＾－３－１×１０＾－１和１×１０＾－４－１×１０＾－２ｍｏｌ／Ｌ磷酸盐，电极响应斜率为２３－２７ｍＶ／ｄｅｃ．电极有较好的稳定性重现性，可望用于磷酸盐的实际分析。     

化学敏感半导体器件

近几年来,由于电化学家和固体物理学家的结合,电化学与半导体技术和理论的相互渗透,提出了一类能够敏感离子或分子的半导体器件,称为化学敏感半导体器件。这类器件的出现不仅影响着电分析化学、医学和生物学等学科,而且对固体物理学的研究也具有重要意义。随着近十多年来离子选择性电极(或称化学敏感选择性电极)技术的发展,Bergveld首先提出了一个化学敏感半导体器件,他称之为离子敏感场效应管(Ion Sensistive Field Effect Transistor,简称ISFET)。Bergveld用普通的金属-氧化物-半导体场效应管(MOSFET),     

次磷酸盐氧化反应历程的研究

对次磷酸盐体系循环伏安曲线－０．４Ｖ（ＳＣＥ）处氧化峰（Ⅱ峰）的特性及本质进行深入研究。结果表明，Ⅱ峰与Ｉ峰直接相关，对应于活性吸附态的偏亚磷酸根氧化生成磷酸根的电极过程，Ⅱ峰是偏亚磷酸根脱出的Ｈａｄｓ＾－离子在电极上发生氧化的结果。确定了吸附态偏亚磷酸根转变为惰性亚磷酸根反应的控速步骤为偏亚磷酸的脱附过程，并估算了脱附速度常数。最后给出可能的吸附态偏磷酸根氧化生成磷酸根的电极历程及总的次磷酸根氧     

结晶型磷—多磷钼酸铵的制备及其离子交换性能的研究

本文叙述了结晶型磷—多磷钼酸铵的制备方法，研究了磷—多磷钼酸铵的化学组成，测定了该化合物的离子交换性能，说明多磷酸根部分取代磷酸根所生成的结晶型磷—多磷钼酸铵对铯离子具有良好的离子交换选择性和较高的离子交换容量，是一类新的结晶型无机离子交换剂。     

结晶型磷一多磷钼酸铵的制及其离子交换性能的研究

本文叙述了弗晶型磷－多磷钼酸铵的制备方法，研究了磷－多磷钼酸铵的化学组成，测定了该经合物的离子交换性能，说明多磷酸根部分取代磷酸根所生成的结晶型磷－多磷钼酸铵对铯离子具有良好的离子交换选择性和较高的离子交换容量，是一类新的结晶型无机离子交换剂。     

一种新的硫酸根离子敏感电极

探索新的材料制备离子敏感电极,研究这些电极的响应特性和响应机理,是离子电极研究的一个新方向［'－"．硫酸根离子敏感电极一直是离子电极研究中的一个难点·本文采用电沉积方法,在铜、钻、玻璃碳和低碳钢体表面沉积了Ni－P系非晶合金硫酸根离子敏感电极,电极对硫酸根离子在卫X10－'～IX10－'mol／L浓度范围内呈Nernst响应,检测下限可达4X10'mol／L,具有良好的重现性和稳定性．该硫酸根离子电极对常见阴离子具有良好的选择性,与迄今所报道的SO广离子敏感电极比较显示了较优异的特性．1实验部分将金属铜（99％,4-5mm）、金属钻…     

杯芳烃化学传感器的研究进展

杯芳烃衍生化得到不同结构和功能基团的主体分子。通过主客体分子作用可包结、螯合客体分子,并可作为敏感材料应用在离子选择电极、离子敏感场效应管、离子光导膜、压电晶体等各种类型的化学传感器上,用于离子和中性分子的识别和检测。     

以双核有机锡化合物为载体的PVC膜磷酸根离子敏感电极

以双（三苄基锡）氧化物为载体制备了一种对磷酸氢根离子具有良好电位响应性能的溶剂聚合膜离子敏感电极。在ｐＨ为７．２０±０．０２的测试液中，电极的线性响应范围为５ ×１０＾－６￣１０＾－１ｍｏｌ／Ｌ，斜率为－３０．１ｍＶ／ｄｅｃ．．用分别溶液法测得其对于各种阴离子的选择性次序：ＨＰＯ４＾２－￣Ｉ＾－〉Ｂｒ＾－〉Ｃｌ＾－〉Ａｃ〉ＳＯ４＾２－。膜相中荷电离子添加实验的结果表明，电极响应系中性载体作用机制。     

新型导电聚合物-聚吡咯溴离子化学传感器

本文用电化学方法把导电聚合物聚吡咯(PPy)修饰在玻碳(GC)电极上, 研究了Br^-离子的掺杂效应和薄膜电极的电化学行为, 研制一种新型Br^-离子选择电极, 电极的响应机制是基于导电聚合物中阴离子的掺杂效应, 详细研究了聚合条件对电极电位响应性能的影响, 电极具有内阻小、响应快、抗毒化能力强、制备简便等优点, 电极对1x10^-^1-x10^-^4MBr^-呈能斯特响应, 检测下限7x10^-^5M, 斜率61mV/PBr^-。本文结果是化学修饰电极技术在化学传感器方面应用的有意义的尝试, 薄膜的良好导电性质使之更易于制备离子敏感电子学器件和生物电子学器件。     

新型载体PVC膜水杨酸根离子敏感电极的研制与应用

报导了以三苄基锡酸酯为中性载体的一种溶剂聚合膜阴离子敏感电极的研制。该电极对水杨酸根离子的电位响具有优良的选择和灵敏度。     

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%.     

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.     

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.