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A Selective Membrane Electrode for Thiocyanate Ion Based on a Bis-taurine-salicylic Binuclear Copper（Ⅱ） Complex as Ionophore

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Chinese Journal of Chemistry 2005年第7期23卷 865-869页

作者：王福昌柴雅琴袁若陈春华戴建远徐岚 ChongqingKeyLaboratoryofAnalyticalChemistry CollegeofChemistryandChemicalEngineeringSouthwestChinaNormalUniversityChongqing400715China

The response characteristics of a new potentiometric membrane electrode with unique selectivity towards thiocyanate ion were reported. The electrode was prepared by incorporating bis‐taurine‐salicylic binuclear copper(II) complex into a plasticized PVC‐membrane. The resulting electrode exhibits anti‐Hofmeister selectivity sequence: SCN − >I − >ClO 4 − >Sal − >NO 3 − >NO 2 − >Br − >Cl − >SO 3 − >SO 4 2− and a near‐Nernstian potential linear range for thiocyanate from 1.0Å×10 −1 to 1.0Å×10 −6 mol·L ‐1 with a detection limit of 8.0Å×10 −7 mol·L −1 and a slope of −56.5 mV/pc in phosphate buffer solution of pH 5.0 at 20°C. The UV/Vis spectra, IR spectroscopy and AC impedance studies showed that the excellent selectivity to thiocyanate was related to the unique interaction between the central metal and the analyte and a steric effect associated with the structure of the carrier. The electrode was successfully applied to the determination of thiocyanate in waste water and human urine samples.

关键词： bis‐taurine‐salicylic binuclear copper(II) complex ion‐selective electrode thiocyanate

Aliphatic Hyperbranched Poly(amido amine)s (PAMAMs): Preparation and Modification

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Chemical Research in Chinese Universities 2005年第3期21卷 345-354页

作者： LIUCui-hua GAOChao YANDe-yue collegeofchemistryandchemicalengineering ShanghaiJiaoTongUniversityShanghai200240P.R.China

A series of water soluble aliphatic hyperbranched poly(amido amine)s(PAMAMs) with the same or similar chemical structure of poly(amido amine) dendrimer was successfully synthesized from commercially available AB and C_n types of monomers by one-pot polymerization via the couple-monomer methodology(CMM). The AB type monomer used in this paper was methyl acrylate, and C_n monomers were multi-amino compounds such as ethylenediamine(EDA), diethylenetriamine(DETA), triethylenetetraamine(TETA), tetraethylenepentaamine(TEPA) and pentaethylenehexamine(PEHA). The reaction mechanism was investigated by means of the mass spectra of the reaction intermediates. Adjusting the feed ratio of AB to C_n, hyperbranched polymers with different terminal groups and properties were obtained. FTIR, NMR, DSC, and TGA were used to characterize the polymers. It was found that the polymers′ properties such as solubility, thermal behaviour and encapsulation capability varied with changing the feed ratio of AB to C_n. Benzoyl and palmitoyl groups were introduced into these macromolecules by acidylation to form amphiphilic hyperbranched polymers which have a high capability to encapsulate water soluble dyes such as Congo red. It is expected that the hyperbranched PAMAMs can play an important role in the industrial applications, such as coatings, cross-linking and phase-transferring agents because of their versatility and availability.

关键词： Hyperbranched Poly(amido amine) Acidylation Amphiphilicity Encapsulation

Stereoselective Synthesis of Piperamide Alkaloids by Modified Ramberg-Bcklund Reaction

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Chinese Chemical Letters 2004年第6期15卷 631-634页

作者： YangLI YuZHANG XiaoLongWANG ZhiHUANG XiaoPingCAO StateKeyLaboratoryofAppliedOrganicChemistry CollegeofChemistryandChemicalEngineeringLanzhouUniversityLanzhou730000

A convenient and rapid approach for the synthesis of piperamide alkaloids 1a - h by the recently developed one-flask Ramberg-Bäcklund reaction was described. The synthesis of 1e was reported for the first time.

关键词： Piperamide alkaloids Ramberg-Backlund reaction.

Two New Diterpene Acetylxylosides from Aster veitchianus

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Chinese Chemical Letters 2004年第4期15卷 425-427页

作者： ErWeiLI KunGAO ZhongJianJIA collegeofchemistryandchemicalengineering NationalLaboratoryofAppliedOrganicChemistryLanzhouUniversityLanzhou730000

Two new acetylxylosides, ent-manool-13-O-β-D-2'-acetylxylopyranoside (1) and ent-manool-13-O-β-D-2', 4'-diacetylxylopyranoside (2) were isolated from Aster veitchianus. Their structures were elucidated by spectrosco... 详细信息

关键词： Aster veitchianus Compositae diterpene xylosides.

A New Amperometric Glucose Biosensor with Naphthol Green B as Mediator

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Chinese Chemical Letters 2004年第2期15卷 208-211页

作者： QinZHAO RuoYUAN ChangLiMO YaQinCHAI XiaZHONG ChongqingKeyLaboratoryofAnalyticalChemistry CollegeofChemistryandChemicalEngineeringSouthwest-ChinaNormalUniversityChongqing400715

Naphthol green B was used, for the first time, as a new mediator in an amperometric glucose biosensor. It is a good mediator, promoting electron transfer from glucose oxidase to graphite electrode. The biosensor shows high sensitivity to glucose at low potential with response time of 30 seconds. The linear range is from 1.5 to 18 靘ol/L glucose with detection limit of 0.5 靘ol/L glucose.

关键词： Naphthol green B mediator glucose oxidase biosensor.

Selective Oxidation of Propane by Lattice Oxygen of Vanadium-Phosphorous Oxide in a Pulse Reactor

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Journal of Natural Gas Chemistry 2005年第2期14卷 88-94页

作者： RusongZhao JianWang QunDong JianhongLiu collegeofchemistryandchemicalengineering BeijingPetrochemicalInstituteBeijing102617China collegeofchemistryandchemicalengineering DaqingPetroleumInstituteDaqing163318China

Selective oxidation of propane by lattice oxygen of vanadium-phosphorus oxide(VPO) catalysts was investigated with a pulse reactor in which the oxidation of propane and there-oxidation of catalyst were implemented alternately in the presence of water vapor. The principalproducts are acrylic acid (AA), acetic acid (HAc), and carbon oxides. In addition, small amounts ofC_1 and C_2 hydrocarbons were also found, molar ratio of AA to HAc is 1.4-2.2. The active oxygenspecies are those adsorbed on catalyst surface firmly and/or bound to catalyst lattice, i.e. latticeoxygen; the selective oxidation of propane on VPO catalysts can be carried out in a circulatingfluidized bed (CFB) riser reactor. For propane oxidation over VPO catalysts, the effects of reactiontemperature in a pulse reactor were found almost the same as in a steady-state flow reactor. Thatis, as the reaction temperature increases, propane conversion and the amount of C_1+C_2 hydrocarbonsin the product increase steadily, while selectivity to acrylic acid and to acetic acid increaseprior to 350℃ then begin to drop at temperatures higher than 350℃, and yields of acrylic acid andof acetic acid attained maximum at about 400℃. The maximum yields of acrylic acid and of aceticacid for a single-pass are 7.50% and 4.59% respectively, with 38.2% propane conversion. When theamount of propane pulsed decreases or the amount of catalyst loaded increases, the conversionincreases but the selectivity decreases. Increasing the flow rate of carrier gases causes theconversion pass through a minimum but selectivity and yields pass through a maximum. In a fixed bedreactor, it is hard to obtain high selectivity at a high reaction conversion due to the furtherdegradation of acrylic acid and acetic acid even though propane was oxidized by the lattice *** catalytic performance can be improved in the presence of excess propane. Propylene can beoxidized by lattice oxygen of VPO catalyst at 250℃, nevertheless, selectivity to AA and

关键词： propane oxidation acrylic acid acetic acid vanadium-phosphorus oxide lattice oxygen oxidation pulse reaction

Multicomponent Kinetic Determination by Wavelet Packet Transform Based Elman Recurrent Neural Network Method

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Chemical Research in Chinese Universities 2004年第6期20卷 698-702页

作者： RENShou-xin GAOLing collegeofchemistryandchemicalengineering InnerMongoliaUniversityHuhhot010021P.R.China

This paper covers a novel method named wavelet packet transform based Elman recurrent neural network(WPTERNN) for the simultaneous kinetic determination of periodate and iodate. The wavelet packet representations of signals provide a local time-frequency description, thus in the wavelet packet domain, the quality of the noise removal can be improved. The Elman recurrent network was applied to non-linear multivariate calibration. In this case, by means of optimization, the wavelet function, decomposition level and number of hidden nodes for WPTERNN method were selected as D4, 5 and 5 respectively. A program PWPTERNN was designed to perform multicomponent kinetic determination. The relative standard error of prediction(RSEP) for all the components with WPTERNN, Elman RNN and PLS were 3.23%, 11.8% and 10.9% respectively. The experimental results show that the method is better than the others.

关键词： Wavelet packet transform Elman recurrent neural network Multicomponent kinetic determination

Stereoslective Synthesis of (Z)-1, 2-Bis(arylseleno)-1-alkene by Addition of Cesium Arylselenolate to Alkynyl Selenide

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Chinese Chemical Letters 2005年第3期16卷 325-326页

作者： RuiLiangLU XinHuaXU WenQiLIU QiuLinZHANG XiongCHEN StateKeyLaboratoryofChemo／BiosensingandChemometrics CollegeofChemistryandChemicalEngineeringHunanUniversityChangsha410082

Alkynyl selenide reacted with cesium arylselenolate in commercial THF at r.t under N2 to afford (Z)-1, 2-bis(arylseleno)-1-alkene in high yields.

关键词： (Z)1-,2-Bis(arylseleno)-1-alkene alkynyl selenide cesium arylselenolate.

Intramolecular Charge Transfer with 1-Naphthanilides and 2-Naphthanilides

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Chinese Journal of Chemistry 2005年第7期23卷 857-864页

作者：王力宏郭琳刘春华张煊江云宝 DepartmentofChemistryandTheKeyLaboratoryofAnalyticalSciencesoftheMinistryofEducation CollegeofChemistryandChemicalEngineeringXiamenUniversityXiamenFujian361005China

A series of 1‐naphthanilides ( 1 ) and 2‐naphthanilides ( 2 ) with varied substituents at the para ‐ or meta ‐position of anilino phenyl ring were prepared and their absorption and fluorescence spectra in a nonpolar solvent cyclohexane were investigated. An abnormal long wavelength emission assigned to the charge transfer (CT) state was found for all of the prepared naphthanilides in cyclohexane. A linear free energy correlation between the CT emission energies and the Hammett constants of the substituent was found within series 1 and 2 . The value of the linear slope with 1 (0.42 eV) was higher than that with 2 (0.32 eV) being close to that of the substituted benzanilides 3 (0.31 eV). The higher slope value suggested higher charge separation extent in the CT state of 1 than that of 2 . It was found that the corresponding linear slope of anilino‐substituted benzanilides remained unchanged when para ‐, meta ‐, ortho ‐, or ortho , ortho ‐methyls were introduced into the anilino moiety, which ruled out the possible contribution of the difference in the steric effect and the electron accepting ability of the naphthoyl acceptor in 1 and 2 . Compared with the early reported N ‐substituted‐benzoyl‐aminonaphthalene derivatives 4 and 5 , it was considered that 1‐naphthoyl enhanced the charge transfer in 1 and the proximity of its 1 L a and 1 L b states was suggested to be responsible. It was shown that 1‐ and/or 2‐substituted naphthalene cores acting as either electron acceptor (naphthoyl) or electron donor (aminonaphthalene) were different in not only electron accepting (donating) ability but also shaping the charge transfer pathway.

关键词： intramolecular charge transfer naphthanilide substituent effect