亚铁氰化钾掺杂聚中性红膜修饰电极的制备及电分析特性

对亚铁氰化钾掺杂的聚中性红膜修饰电极的制备及其电化学行为和Ｆｅ（ＣＮ）６４－在该电极上的催化作用进行了研究。结果表明,该修饰电极对Ｆｅ（ＣＮ）６４－存在较强的电催化作用,催化峰电流与Ｆｅ（ＣＮ）６４－的浓度在 １．０×１０－５～２．０×１０－３ ｍｏｌ／Ｌ范围内呈良好的线性关系,检测限可达５×１０－６ｍｏｌ／Ｌ     

阿霉素在钴离子注入修饰电极上的电化学行为及其应用

阿霉素在０．１ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ（ｐＨ４．６２）缓冲溶液中用注入钴的修饰玻碳电极为工作电极进行伏安测定,得到一良好的还原峰;Ｅｐ＝－０．５２２Ｖ（ｖｓ．ＳＣＥ）。峰电流与阿霉素浓度在１．４×１０＾－６－１．４×１０＾－６ｍｏｌ／Ｌ和１．４×１０＾－６－５．６×１０＾－５ｍｏｌ／Ｌ范围内呈线性关系,。     

铁的单点络合滴定法研究

本研究了Ｆｅ＾３＋的单点络合滴定法，导出了定量关系式，比较了以铂电极为指示电极和以ＰＶＣ膜四氯络铁（Ⅲ）阴离子电极为指示电极时电位测量的稳定性及所得的分析结果。在Ｆｅ＾３＋浓度为１．０００×１０＾－３ｍｏｌ／Ｌ时，１８次实验的平均值为１．０２×１０＾－４ｍｏｌ／Ｌ，相对偏差小于１．７％；Ｆｅ＾３＋在５．０×１０＾３ｍｏｌ／Ｌ以上时，相对偏差小于０．１％；其浓度小于１０＾－３ｍｏｌ／Ｌ而大于５×１     

耐尔兰共价键合修饰石墨电极的电化学行为及对NADH的响应研究

本文报道了耐尔兰Ａ键合型石墨修饰电极的制作方法,详细研究了修饰电极的电化学行为及对ＮＡＤＨ的响应情况。在ｐＨ７．４的磷酸盐缓冲溶液中,用该电极在０ｍＶ（ｖ．ｓＳＣＥ）电位下检测ＮＡＤＨ,响应电流与ＮＡＤＨ浓度在４．３×１０－６～５．２×１０－４ｍｏｌ·Ｌ－１范围内成线性关系,检测下限为１．２×１０－６ｍｏｌ·     

硼掺杂多晶金刚石薄膜电极的电化学特性

用循环伏安法和恒电位法研究了硼掺杂多晶金刚石薄膜电极（ＤＦＥ）的若干电化学特性。电极面积４×４ｍｍ＾２。在０．１ｍｏｌ／Ｌ ＫＣｌ，ＮａＮＯ３，ＮａＯＨ和ＫＨ２ＰＯ４＋Ｎａ２ＨＰＯ４（ｐＨ＝６．８６）电解质溶液中电势窗口均为－５００￣＋８００ｍＶ；而在０．１ｍｏｌ／Ｌ ＨＣｌ和Ｈ２ＳＯ４溶液中电势窗口为－２００￣＋１１００ｍＶ．Ｋ３Ｆｅ（ＣＮ）６的氧化峰电位为＋５００ｍＶ，与Ｐｔ电极测量相同；校正     

鸟嘌呤—铜配合物在汞电极表面上的电吸附性的研究

在０．０２ｍｏｌ／Ｌ ＮａＨＣＯ３－０．０５ｍｏｌ／Ｌａ２ＳＯ４介质中、用极谱法和伏安法研究表明,铜－乌嘌呤配合物在汞电极表面上的吸附服从Ｌａｎｇｍｕｉｒ吸附,测得其饱和吸附量Γｍ＝１．１×１０＾－１０ｍｏｌ／ｃｍ＾２,吸附系数β＝４．７×１０＾４,吸咐自由能△Ｇ°＝－３６．６ｋＪ／ｍｏｌ。在８×１０＾－６ｍｏｌ／Ｌ Ｃｕ＾２＋离子存在下,可用示差脉冲阴极吸附溶出法测定８×１０＾－１０～１×１０＾     

铂黑修饰酶电极测定胆碱

利用电化学方法在玻碳电极上均匀沉积亚微米粒度铂黑并进而修饰一层胆碱氧化酶膜,制成了胆碱酶电极。以计时电流法测定氯化胆碱,检测下限为 ７．４ μｍｏｌ／Ｌ,线性范围２．４×１０－２～ １．０ ｍｍｏｌ／Ｌ,重现性好,使用寿命较长。     

聚N,N-双水杨醛乙二胺合钴修饰超微电极的制备及其在一氧化氮测定中应用的研究

通过电化学聚合法制备了聚Ｎ，Ｎ－双水杨醛乙二胺合钴［ｐｏｌｙＣｏ（Ｓａｌｅｎ）］修饰超微电极，研究了该修饰电极的电催化性质及其在一氧化氮（ＮＯ）测定中的应用．实验结果表明，ｐｏｌｙＣｏ（Ｓａｌｅｎ）修饰超微电极对ＮＯ的测定有高的灵敏度，ＮＯ的浓度在２．０×１０－８～２．８×１０－６ｍｏｌ／Ｌ范围内，电流与浓度呈良好的线性关系，线性相关系数为０．９９９８，检出限为１．０×１０－８ｍｏｌ／Ｌ；该电极进一步修饰Ｎａｆｉｏｎ后，生物体中常见的物质如抗坏血酸、儿茶酚胺类神经递质的代谢物、ＮＯ的氧化产物ＮＯ－２等不干扰测定．本传感器可以满足ＮＯ在体分析的需要．     

铜铂微粒修饰微电极测定一氧化氮

详细报道了金属铜，铂微粒微电极用于ＮＯ的检测，该修饰电极对ＮＯ具有催化氧化作用，当ＮＯ浓度在８．２×１０＾－８－４．５×１０＾－６ｍｏｌ／Ｌ内，浓度与峰电流呈线性关系，相关系数为０．９９７。     

大黄酚的电化学行为及其应用研究

大黄酚在０．１５ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ（ｐＨ４．９）底液中，出现一灵敏的示波极谱导数峰，峰电位为－０．４５Ｖ（ｖｓ，ＳＣＥ），峰电流与大黄酚浓度在２．０×１０＾－７－５．０×１０＾－６ｍｏｌ／Ｌ范围内成线性关系，检测限为２．０×１０＾－６ｍｏｌ／Ｌ。用于生药大黄中大黄酚的测定，回收率为９２．４％－１０８．４％。用多种电化学手段研究体系的电化学行为，测得电极反应电子数ｎ＝２。体系具有吸附性，并     

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.     

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.     

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.     

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.