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Sensing characterization of Sn/In/Ti nanocomplex oxides for CO, CH_4 and NO_2

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Science china(Technological Sciences) 2007年第1期50卷 18-26页

作者： BAI ShouLi1, TONG ZhangFa2, LI DianQing1, HUANG XiaoWei3, LUO RuiXian1 & CHEN AiFan1 1 State Key Laboratory of chemical Resource engineering, Beijing university of chemical technology, Beijing 100029, china 2 School of chemistry and chemical engineering, Guangxi university, Nanning 530004, china 3 college of Biochemical engineering, Beijing Union university, Beijing 100023, china 1. State Key Laboratory of chemical Resource engineering Beijing University of Chemical Technology Beijing 100029 China 2. School of chemistry and chemical engineering Guangxi University Nanning 530004 China 3. college of Biochemical engineering Beijing Union University Beijing 100023 China

The nanocomplex oxides of Sn-In and Sn-In-Ti were prepared by controlled co-precipitation method as sensing materials of semiconductor gas sensors for detection of CO, CH4 and NO2. Through manipulating the Sn/In cation ratio, metal salt total concentration, precipitation pH value and aging time, the nanocrystalline powders were successfully derived with chemical homogeneity and superior thermal stability, compared with the single component oxides. The particle size and morphology, surface area, and thermal and phase stabilities were characterized using TEM, TG-DTA, BET and XRD. The sensing tests showed that the Sn-In com-posites exhibit high sensitivity and selectivity for CO and NO2. The introduction of TiO2 enhanced CH4 sensitivity and selectivity, particularly, additives of Pd and Al2O3 as a dopant and surface modification greatly enhanced the sensing properties. The sensitivity depended on the composition of composites, calcination temperature and operating temperature. The optimal values were (25%In2O3- 75%SnO2)-20%TiO2 for ternary composite, 600 and 300℃, respectively. Temperature-programmed de-sorption (TPD) studies were employed to explain the gas adsorption behavior dis-played by the surface of nanocomposites and X-ray photoelectron spectroscopic (XPS) analysis was used to confirm the electronic interactions existing between oxide components. The sensing mechanism of the nanocomposites was attributed to chemical and electronic synergistic effects.

关键词： SnO2-In2O3-TiO2 nanocomposites CO NO2 CH4 gas sensing

Preparation of Exo-tetrahydrodicyclopentadiene Using SiW/Hβ Catalyst

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china Petroleum Processing & Petrochemical technology 2011年第3期13卷 41-46页

作者： Kang Zhuozhuo Wu Wenliang Zhou Zhiwei (college of chemistry and chemical engineering,Nanjing university of technology,Nanjing 210009) Nanjing Univ Technol Coll Chem & Chem Engn Nanjing 210009 Peoples R China

Exo-tetrahydrodicyclopentadiene （exo-TCD） is an important high-energy fuel. Silicotungstic acid （SiW） immobilized on H-type β zeolite （Hβ） at room temperature were used to prepare the Hβ zeolite catalysts with different SiW contents. Catalytic performances of the catalysts were investigated during the preparation of exo-TCD via isomerization of endo-tetrahydrodicyclopentadiene （endo-TCD）. The properties of catalysts were characterized by XRD, temperature pro- grammed desorption of ammonia （NHa-TPD）, FT-IR, and N2-adsorption techniques. SiW was highly dispersed on the surface of Hβ zeolite, and the 10% SiW/Hβ zeolite catalyst had the highest amount of weak acidity among all SiW/Hβ zeolite catalysts. The influence of different factors on isomerization reaction was investigated. At a reaction temperature of 240 ℃, a n（cyclohexane） / n（endo-TCD） ratio of 10, a m（catalyst）/m（endo-TCD） ratio of 0.3, an initial pressure of 1.0 MPa, and a reaction time of 1.5 h in the presence of 10% SiW/Hβ catalyst calcined at 400 ℃, the conversion of endo-TCD reached up to 92.0%, with the yield of exo-TCD equating to 51.0%.

关键词： exo-tetrahydrodicyclopentadiene endo-tetrahydrodicyclopentadiene Hβ zeolite silicotungstic acid (SiW)

Prophylaxis and Therapy of Isaria felina on Acute Renal Failure Induced by Glycerin in Rats

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Chinese Herbal Medicines 2012年第4期4卷 319-323页

作者： YANG Xi-hua2,3,ZHANG Sheng-wan1,REN Lian-sheng3,BAI Xi-hua3 1.college of Life Science,Shanxi university,taiyuan 030006,china 2.college of chemistry and chemical engineering,Shanxi university,taiyuan 030006,china 3.Department of Comparative Medicine,Shanxi Cancer Institute,taiyuan 030013,china [a] college of Life Science Shanxi University Taiyuan 030006 China [b] college of chemistry and chemical engineering Shanxi University Taiyuan 030006 China [c] Department of Comparative Medicine Shanxi Cancer Institute Taiyuan 030013 China

Objective To evaluate the prophylaxis and therapy of Isaria felina(IF) on glycerin-induced acute renal failure(ARF) in *** Forty male Wistar rats were divided into control,model,Uremic Clearance Granule(UCG,positive control),high-and low-dose IF *** in the high-and low-dose IF groups were ig administered with 200 and 100 mg/kg IF,respectively,while rats were ig administered with 3.6 g/kg UCG successively for 7 d to establish UCG *** rats in model,control,and drug-treated groups were im injected with 8 mL/kg 50% glycerin after drinking was quitted for 24 h to induce ARF in *** drugs were continued to give *** level of blood urea nitrogen(BUN) and serum creatinine(SCr) were determined 24 and 72 h after the injection of glycerin,also the kidney was dissected for pathology *** Im injection with 8 mL/kg 50% glycerin could successfully induce ARF in *** dose of 200 mg/kg IF could reduce the high levels of BUN and SCr,and ameliorate the pathological damage of the *** IF has good protective and therapeutic effects on ARF and it is a potential and valuable Chinese herb for ARF.

关键词： acute renal failure blood urea nitrogen glycerin Isaria felina serum creatinine

Metal-amyloid-β peptide interactions: a preliminary investigation of molecular mechanisms for Alzheimer’s disease

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Science china chemistry 2007年第4期50卷 453-467页

作者： JIAO Yong & YANG Pin Key Laboratory of chemical Biology and Molecular engineering of Ministry of Education, Institute of Molecular Science, Shanxi university, taiyuan 030006, china 1. Key Laboratory of chemical Biology and Molecular engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China

Although humans have spent exactly 100 years combating Alzheimer’s disease (AD), the molecular mechanisms of AD remain unclear. Owing to the rapid growth of the oldest age groups of the popula-tion and the continuous increase of the incidence of AD, it has become one of the crucial problems to modern sciences. It would be impossible to prevent or reverse AD at the root without elucidating its molecular mechanisms. From the point of view of metal-amyloid-β peptide (Aβ) interactions, we review the molecular mechanisms of AD, mainly including Cu2+ and Zn2+ inducing the aggregation of Aβ, cata-lysing the production of active oxygen species from Aβ, as well as interacting with the ion-channel-like structures of Aβ. Moreover, the development of therapeutic drugs on the basis of metal-Aβ interactions is also briefly introduced. With the increasingly rapid progress of the molecular mechanisms of AD, we are now entering a new dawn that promises the delivery of revolutionary developments for the control of dementias.

关键词： Alzheimer’s disease (AD) amyloid-β peptide Cu2+ Zn2+ molecular mechanisms aggregation active oxygen species ion channel

A novel four-component reaction involving ring-opening/recyclization of 1,3-thiazolidinedione

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Science china chemistry 2010年第4期53卷 863-868页

作者： SUN Jing, XIA ErYan, ZHANG LiLi & YAN ChaoGuo college of chemistry & chemical engineering, Yangzhou university, Yangzhou 225002, china 1. college of chemistry & chemical engineering Yangzhou University Yangzhou 225002 China

The multicomponent reactions of 1,3-thiazolidinedione, malononitrile, aromatic aldehydes and α-phenylethylamine or β-phenylethylamine in acetonitrile at room temperature produce dihydrothiophene ureidoformamide derivatives in moderate yields through a domino ring-opening/recyclization reaction of 1,3-thiazolidinedione. On treatment with DDQ, dihydrothiophenes are dehydrogenated to convert efficiently to thiophenes in the mild condition.

关键词： multicomponent reaction ring-opening recyclization dihydrothiophene thiazolidinedione

Improved electrochemical performances of polyaniline nanotubes-poly-L-lysine composite for label-free impedance detection of DNA hybridization

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Science china chemistry 2010年第6期53卷 1371-1377页

作者： YANG Tao,JIANG Chen,ZHANG Wei & JIAO Kui Key Laboratory of Eco-chemical engineering,Ministry of Education college of chemistry and Molecular engineering,Qingdao university of Science and technology,Qingdao 266042,china 1. Key Laboratory of Eco-chemical engineering Ministry of Education college of chemistry and Molecular engineering Qingdao University of Science and Technology Qingdao 266042 China

A sensitive label-free DNA hybridization biosensing platform was fabricated based on the synergistic effect of polyaniline nanotubes (PANInt) and poly-L-lysine (pLys).The composite of pLys and PANInt was coated onto the carbon paste electrode (CPE) to form a uniform and very stable nanocomposite *** pLys in the composite film not only acts as a membrane to retain good electron transfer capability of PANInt even at physiological pH,but also possesses fine biocompatibility for *** probes with negatively charged phosphate groups were readily linked to the positively charged pLys surface due to the strong electrostatic *** synergistic effect of PANInt and pLys could significantly enhance the sensitivity of DNA hybridization *** phosphinothricin acetyltransferase (PAT) gene fragment from transgenic corn and the polymerase chain reaction amplification of the terminator of nopaline synthase gene from the real sample of a kind of transgenic soybean were detected by this DNA electrochemical biosensor via label-free impedance *** stable composite gives convenient permselectivity properties as a transducer material for the design of modern electrochemical impedance biosensor using [Fe(CN)6]3-/4as an indicator.

关键词： poly-L-lysine polyaniline nanotubes DNA electrochemical biosensor PAT gene NOS gene

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2:F film optically transparent electrode

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Science china chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2 & NIU Shuyan1,2 1. college of chemistry and Molecular engineering, Qingdao university of Science and technology, Qingdao 266042, china 2. college of chemistry and chemical engineering, Ocean university of china, Qingdao 266003, china Correspondence should be addressed to Jiao Kui 1. college of chemistry and Molecular engineering Qingdao University of Science and Technology 266042 Qingdao China 2. college of chemistry and chemical engineering Ocean University of China 266003 Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2:F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

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炭微球的结构演变:从实心到中空(英文)

新型炭材料 2010年第6期25卷 431-437页

作者：杨永珍刘旭光罗秋苹金琳许并社新材料界面科学与工程教育部重点实验室(太原理工大学) 山西太原030024 太原理工大学材料科学与工程学院山西太原030024 太原理工大学化学化工学院山西太原030024

采用简单的空气氧化法由实心炭微球制备中空结构的炭微球。通过场发射扫描电子显微镜、高分辨透射电子显微镜、X-射线衍射仪、拉曼光谱和热重分析仪对产物的形貌和结构进行表征。结果表明:中空炭微球的石墨化程度较低。在炭微球的空气... 详细信息

采用简单的空气氧化法由实心炭微球制备中空结构的炭微球。通过场发射扫描电子显微镜、高分辨透射电子显微镜、X-射线衍射仪、拉曼光谱和热重分析仪对产物的形貌和结构进行表征。结果表明:中空炭微球的石墨化程度较低。在炭微球的空气热氧化过程中,反应温度对炭微球从实心到中空的结构演变起着关键性的作用,温度越高,中空炭微球的内径越大、壁越薄。其形成机理可认为是炭微球的曲率和结晶度协同作用的结果。亦即,实心炭微球进行热氧化时,其内部的大曲率和低结晶度更易氧化,以致形成中空炭微球。

关键词：炭微球氧化中空炭微球形成机理

Boron rings containing planar octa- and enneacoordinate cobalt, iron and nickel metal elements

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Science china chemistry 2008年第7期51卷 607-613页

作者： LUO Qiong School of chemistry and chemical engineering, Central South university, Changsha 410083, china School of chemistry and chemical engineering Central South UniversityChangsha 410083China

For a series of boron rings with planar hyper-coordinate 8th group transition metal atoms, singlet 1FeB8-2, multiplet kFeB9n (n = -1, k = 1; n = 0, k = 2), singlet 1CoB8n(n = -1, +1, +3), multiplet kCoB9n (n = +1, k = 2; n = 0, k = 1) and singlet 1NiB9+, the geometry structures have been optimized to be local minima on corresponding potential hyper-surfaces. The electron structures are discussed by orbital analysis and the aromaticity is predicted by nucleus-independent chemical shifts calculation at both the B3LYP/6-311+G* and BP86/6-311+G* levels of theory, respectively. The results suggest that all these structures with high symmetry planar geometries are stable and have aromatic properties with six π valence electrons.

关键词： planar hyper-coordinate transition metal DFT