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March 15,2010
Volume 3,Issue 5
Pages 426-529
Subject Area:Distillation,Applied Chemistry (Specifically Applied to the Relevant Disciplines),Electrochemistry,Analytical Chemometrics,Functional Polymer (including Liquid Crystal Polymer Chemistry)

Title: Determination of Phthalanilic acid in Baoying by HPLC

Authors: LI Qingang
PP: 526～529
Abstract: Objective: To set up the determination method of phthalanilic acid in plant growth regulator Baoying. Methods: A high performance liquid chromatography was employed. Chromatographic column: Lichrsorb-C18 (4.6 mm×150 mm, 5 μm); detective wavelength: 233 nm; mobile phase: Acetonitrile-phosphoric acid （volume ratio 37.5∶36.5,pH=5.5）+L-hexadecyl trimethyl ammonium bromide (250 mmol/L); flow rate: 1 mL/min. Results: phthalanilic acid had good linear relation with peak area at the range of 6.8~230.0 μg/mL, the averagerecovery rate was 97.99%, and relative standard deviation (RSD) was 1.57％ (n=6). Conclusion: The method is accurate, and has good reliability and reproducibility, so it can be used in the quality control for this preparation.
Keywords: pesticide project; Baoying; phthalanilic acid; high performance liquid chromatography; content determination

Title: Study on AN-IA copolymerization initiated byoxidation-revivification’s solicitaion system

Authors: LIU Fei, GUO Xianying
PP: 520～525
Abstract: High molecular weight polyacrylonitrile (PAN) was obtained by the free-radical suspension copolymerization of acrylonitrile (AN) and itaconic acid (IA) which was carried out in H2O using NaHSO3-K2S2O8 as initiator, using two methods of routine and microwave . Measured it’s viscosity-average molecular weight by Ubbelohde viscometer, then analyzed the impact of monomer IA on the copolymer.And also studied the impact of the monomer concentration，initiator concentration，reaction time，reaction temperature and other factors on the reaction system.The result indicated that，increasing monomer concentration and initiator dosage，raising reaction temperature，all may enhance conversion of the polymerization system，but can reduce the molecular weight of the copolymer，and molecular weight distribution was expanded.Increasing the amount of monomer ratio will reduce the copolymer molecular weight.At last, the paper analyzed the differential scanning calorimetry (DSC) curve and the thermogravimetry (TG) curve of the production.
Keywords: polymer material；acrylonitrile；itaconic acid；copolymerization；molecular weight；differential scanning calorimetry； thermogravimetry

Title: Macro-kinetics studies on non-solvent catalytic hydrogenation of 2,4-diaminotoluene

Authors: KONG Lingqi, LI Chunxin, GE Jijun, CAO Chuanbo, ZHANG Guoping
PP: 512～519
Abstract: The process and kinetics of liquid phase hydrogenation of 2,4-dinitrotoluene (DNT) to 2,4-toluene diamine (TDA) with no solvent were observed with a self-designed device at 100~140℃, 1.0~3.0 MPa, Ni catalyst concentration (CNi) of 0.03%~2.00% by weight，and content of TDA 30％～70% by weight. Experimental data showed that the reaction has different properties in the low DNT content region (CDNT <7.14 mol·m-3, LDCR) from that in the high DNT content region (CDNT>7.14 mol·m-3, HDCR). In HDCR, the reaction was controlled by adsorptive process, and CNi was in direct proportion to the reaction rate while CDNT had almost no effect on it. In LDCR, the reaction was controlled by interface reaction process, and CNi had no effect on the reaction rate in a certain range while CDNT was in direct proportion to it. In both regions the reaction rate is about in direct proportion to hydrogen pressure. The apparent activation energies of the reaction in both regions were also obtained, 17.62 and 15.67 kJ·mol-1 respectively, which reveald that the reaction was more easily occurred than that in the solvent environment. The content of TDA had no effect on the reaction rate. The macro-kinetics was obtained through data fitting. An excellent agreement between the model predictions and the experimental data was observed, which showed that the study result could provide theoretical direction to non-solvent catalytic hydrogenation of DNT and hydrogenation reactor design.
Keywords: chemical reaction engineering；kinetic model; catalystic hydrogenation; 2,4-dinitrotoluene; non-solvent

Title: Calculation model of agglomerate sizes in vibrating fluidization of nano-particles

Authors: WANG Hui, ZHOU Tao, AI Qiong
PP: 504～511
Abstract: In this study, the fluidization behavior of SiO2 nano-particles and the effects of vibration parameters on size of agglomerates have been systematically investigated in a bed of 40 mm in diameter. Base on Richardson-Zaki equation and Stokes law, a mathematical model was developed in use of studying vibrating fluidization with nano-particles. According to these experimental results slugging and channeling of bed disappeared, the minimum fluidization velocity is reduced, the measured agglomerate size is decreased and fluidization quality was significantly improved due to introduction of vibration energy. The effect of vibration on agglomeration in fluidization of nano-particles is two-sided. Compared with vibration amplitude, vibration frequency had a comparatively significant effect on agglomerates’ size. The sizes of agglomerates of the predicated values and the experimental data decreased with increasing vibration intensity, and were agreement well with each other under vibration condition. In addition, the degree of the size-segregation of the agglomerates decreased with increasing of vibration intensity.
Keywords: multiphase chemical reaction engineering；vibrated fluidized bed; nano-particles; size of agglomerates; vibration parameters; model

Title: The development of study on molecular distillation technology and its application in pharmaceutical industry

Authors: SHEN Yinghua, ZHOU Zhongqun, WANG Zhongde, ZHANG Linxiang
PP: 498～503
Abstract: The molecular distillation technology, as a special kind of high-separated technology, has a prospect for development. This paper combines with the latest research of molecular distillation technology at home and abroad, and makes a narration of the theory to research and the device to improve in the molecular distillation device, and mainly stresses in the introduction on the research condition of the promising centrifugal molecular distillation device, and states the new progress of application of the molecular distillation technology in pharmaceutical industry.
Keywords: distillation； molecular distillation; review; separation purification; pharmaceutical industry

Title: Studies on microwave-assisted synthesis and biological activities of 5-(trifluoromethyl )-1,3,4-thiadiazol ureas

Authors: LI Kejian
PP: 492～497
Abstract: A simple and efficient method is developed for the synthesis of 5-trifluoromethyl-1,3,4-thiadiazol ureas II from heterocyclic amino compounds and intermediate I under solvent conditions using microwave irradiation.The structures of the titled compoundsⅡ are characterized by 1H nuclear magnetic resonance spectra （1HNMR）, liquid chromatographic mass spectrometry（LC-MS）, elemental analysis and X-ray diffraction (XRD) data. The results of the biological activities of the title compounds indicate that the titled compounds have low herbicidal and insecticidal activities, but good fungicidal activities. Some of them have good plant growth regulation activities.
Keywords: organic chemistry; 5-trifluoromethyl-1,3,4-thiadiazol ureas; microwave; organic synthesis; biological activities

Title: Study on synthesis and fluorescence characteristics of L-lysine-anisaldehyde Schiff base and its cupric complex

Authors: YANG Rui, LI Qun
PP: 488～491
Abstract: A new Schiff base and its cupric complex of L-lysine and anisaldehyde were synthesized by stepwise synthesis method in anhydrous system, with basic essential amino acid L-lysine and natural product anisaldehyde as precursor. The melt points of the ligand and the cupric complex were measured as 209.4～209.7℃ and 225.3～225.5℃ respectively by WRS-1B digital melting point apparatus. The composition of the products was characterized by element analysis and IR spectra methods. The possible structures of the Schiff base and the complex have been discussed as C14H18N2O3K and CuL2. Fluorescence spectrum of the ligand and the complex were studied. Results showed that both the ligand and the complex may have fluorescence capacity with fluorescence of 425 nm and 453 nm respectively.
Keywords: applied chemistry; L-lysine; anisaldehyde; schiff base; Cu complex; fluorescence capacity

Title: Improved enzyme immobilization for enhanced bioelectrocatalytic activity of glucose sensor

Authors: WANG Yiting, YU Lei, ZHU Ziqiang, LOU Lei, DU Weijie, ZHU Jianzhong
PP: 482～487
Abstract: A highly sensitive and stable glucose sensor based on the synergic action of multi wall carbon nanotube (MWCNTs) and ZnO nanoparticles has been developed. Glucose oxidase (GOx) is firmly immobilized on the ZnO nanoparticles surface due to their large difference in the isoelectric point (IEP), while the ZnO nanoparticles were deposited on the negatively charged MWCNTs layer. A cationic polydiallyldimethylammonium chloride (PDDA) layer was coated on the GOx layer. The unique sandwich-like layer structure (PDDA/GOx/ZnO/MWCNTs) formed by self-assembling provides a favorable microenvironment to keep the bioactivity of GOx and to prevent enzyme molecule leakage. Amperometric detection of glucose was carried out at 100 mV (vs. Ag/AgCl) in 0.05 mol/L phosphate buffer solution (pH=6.8) with a wide linear response range of 0.1 to 16 mmol/L by the sensor with 0.5 U GOx, with a sensitivity of 50.2 mA·cm-2·mol-1·L-1 and a detection limit of 250 nmol/L (3σ) by the sensor with 2.0 U GOx. Results obtained from the glucose sensor directly in human blood serum were compared with ones obtained by spectrometry by a local hospital. On testing 100 samples of serum, the correlation coefficient reaches 0.997.
Keywords: electrochemistry；glucose sensor; glucose oxidase; MWCNTs; ZnO particles; synergic action

Title: Synthesis and characterization of superparamagnetic Fe3O4 nanoparticles

Authors: SHI Xiaoqiu, WANG Yuqiao, SUN Yueming
PP: 479～481
Abstract: Small particle size, high magnetic saturation, low magnetic coercivity superparamagnetic Fe3O4 was synthesized by coprecipitation method and sol-gel method, which were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer(VSM). The results shown us the crystalline, particle average diameter (10~40 nm), magnetic saturation (47.61~53.85 emu/g ) and magnetic coercivity (close to zero).
Keywords: inorganic chemical； Fe3O4; coprecipitation; sol-gel method

Title: Synthesis，crystal structure and optical properties of a novel Cu(Ⅱ) complex containing imidazole-carboxylate ligand

Authors: NIU Helin, CHEN Jitang, ZHANG Shengyi
PP: 475～478
Abstract: A novel complex-［Cu5(C10H7N2O2)4(SO4)2(N3)(H2O)2］n was prepared under hydrothermal condition. The structure of the complex was determined by single crystal X-ray diffraction analysis． The crystal is of monoclinic system，space group C 2/m with a=17.857(8) 姒，b=19.720(9) 姒， c=7.923(4) 姒， β=106.571(6)°， V=2 674.13(2) 姒3， Z=1， Dc=5.475 g·cm-3，F(000)=4 186， wR=0.080． In the molecular structure of ［Cu5(C10H7N2O2)4(SO4)2(N3)(H2O)2］n，two crystallographically independent Cu(Ⅱ) ions with different coordination environments were observed, the center Cu(Ⅱ) atom was six coordinated by four O atoms of the ligand(L) and two O atoms of water molecules to form a distorted octahedral geometry．The crystal has good fluorescence property.
Keywords: inorganic chemistry; imidazole-carboxylate；multinuclear；crystal structure；fluorescence property

Title: Research in fluorescence enhancement of CdSe QDs via surface modification

Authors: WEI Yufeng, YU Zhiyong
PP: 468～474
Abstract: Oil-soluble CdSe semiconductor nano-particles synthesized by way of organic-heat-solvent were modified by silane coupling agent and a water-soluble amphoteric low-molecular-weight polymer poly(acylic acid)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE-PAA) which has a property of fluorescence. It employed both the effective realization of Water-soluble quantum dots(QDs) and greater increase in the fluorescent quantum yield of QDs. The fluorescence enhancement of CdSe QDs which did’t has the shell - nuclear structure modified via different methods also had been studied.
Keywords: inorganic chemistry; quantum dots; surface modifying; fluorescence enhancement; water-soluble

Title: Application of BP neural network based on factor analysis on rational synthesis of microporous materials

Authors: HUO Weifeng, LI Jiyang, YU Jihong, XU Ruren
PP: 462～467
Abstract: Aiming at the directional synthesis problem of microporous crystal compounds, this work presents a new mode of data mining process in which the pretreatment by factor analysis was used to reduce the redundant attributes and then the back propagation (BP) neural network built with these factors as input was used to predict the type of the products. The application of such method on the analysis of the synthesis data of aluminiumphosphate shows that the method can not only diminish computation, but also build product predicting model which has good predicting capacity. The prediction correct rate is 86.58%. This work will further assist in rational synthesis of microporous materials.
Keywords: inorganic chemistry; data mining; back propagation neural network; factor analysis; rational synthesis

Title: Application of delaunay triangulation method in near infrared spectral analysis

Authors: LI Yankun, XU Heng, CAI Wensheng, SHAO Xueguang
PP: 457～461
Abstract: Delaunay triangulation (DT) is a method to construct space mesh. The proposed method constructs DT mesh of near-infrared (NIR) spectral data in the principal component (PC) space of partial least squares (PLS) for distinguishing the similarity of samples. The method named as PLS-PC-DT is introduced into quantitative analysis of NIR spectral data. PLS-PC-DT is a fast and simple method. Furthermore, it is no need to construct the calibration model. When applied to predict the moisture, oil, protein and starch values of the corn samples, the result indicates that the proposed method provides an effective tool for the quantitative analysis of the NIR spectral data.
Keywords: analytical chemistry; near-infrared spectroscopy; quantitative analysis; partial least squares; Delaunay triangulation

Title: Synthesis and characterization of hydrophobically-modified polyacrylamide

Authors: LI Jie, QIANG Yinghuai
PP: 450～456
Abstract: Hydrophobically-modified polyacrylamide was synthesized in the way of micro-emulsion polymerization in this paper, compared to common polymerization, which required reduction of the hydrophobic monomer, but made the polymer hydrophobic interaction greatly enhanced. So it helped to improve the solubility of polymers. Then the influences of emulsifier and initiator on polymer solution were discussed under constant concentration of monomer and temperature, and the association action and aggregation morphology were characterizated through infrared spectra and scanning electron microscopy.
Keywords: polymer chemistry; micro-emulsion; emulsifier; initiator

Title: Primary investigation on new design for branched polymers by mercapto chain-transfer polymerization

Authors: ZONG Yiwu, JIANG Jinqiang, NING Chao, DAI Peng, LIU Xiaoya
PP: 442～449
Abstract: The sodium s-alkylthiosulfuric-containing styrene monomer (SATCS) was designed and synthesized through the Bunte salt reaction, which could be used as a branched monomer together with styrene (St) and azobisisobutyronitrile (AIBN) to prepare branched polystyrene (BPS) in dimethyl sulfoxide (DMSO) solvent. The branched polymers were characterized by multiple detectors gel permeation chromatography/laser light scattering/differential viscometer (GPC/LLS/DV) in THF. It was found that the molecular weight of BPS increased with the increasing reaction time, while the branched magnitude decreased, which indicated that through the radical copolymerization of SATCS monomer and styrene, the polystyrene could be branched.
Keywords: macromolecular chemistry and physics; hyperbranched; mercapto chain-transfer; radical polymerization; self-condensing vinyl polymerization; Bunte salt

Title: Study on ionic liquid［bmim］PF6 as plasticizer for PVC paste resin

Authors: PU Jiayin, HOU Linxi, ZHANG Ruifeng, LIU Yan
PP: 437～441
Abstract: The green solvent, room temperature ionic liquid ［bmim］PF6（1-butyl-3-methylimidazolium hexafluorophosphate) was used as plasticizer for polyvinyl chloride （PVC） paste resin. The mechanical properties and thermal stability of the PVC paste resin samples were determined by universal testing machine and thermal gravimetry/differential thermal analyzer (TG/DTA), and compared with dioctyl phthalate （DOP）, dibutyl phthalate (DBP), tributyl citrate (TBC) on plasticizer permanence. The results showed that with the increasing of ［bmim］PF6 dosages, the tensile strength and elastic moduli dropped; and their elongation at break were improved obviously; and the thermal stability of PVC paste resin membranes were improved obviously, permanence properties were more excellent than DOP, DBP, TBC plasticized membranes. It can be used in producing medical catheters as plasticizers because that it had good biocompatibility: its cytotoxicity, pyrogen and hemolytic all were fitted to national standards.
Keywords: polymer chemistry; pdyvinyl chloride paste resin; [bmim]PF6; plasticizer

Title: Synthesis of copper-doped ZnS/DFHMA-co-MAA fiber composites and its performance of photocatalytic hydrogen production from water

Authors: FAN Wenjuan, ZHOU Zhengfa, XU Weibing, REN Fengmei, MA Haihong
PP: 431～436
Abstract: The carboxylic fluorocarbon polymer dodecafluoroheptyl methacrylate-co-methacrylic acid (DFHMA-co-MAA) were prepared by solution polymerization. Using electrospinning to produce fluoropolymer nanofibers, the average diameter of the nanofibers is about 150 nm. and then the copper-doped zinc sulfide (ZnS) particles of about 200 nm in size were immobilized on the surface of DFHMA-co-MAA fiber through solvothermal method. The composites was characterized by X-ray diffraction, electron spectrum,ultraviolet visible diffuse reflectance spectrum, thermogravimetric analysis and the experiment of light degradation resistance. The experiment of photocatalytic hydrogen production from water was also studied, the result show that the photocatalytic ability of copper-doped ZnS/DFHMA-co-MAA fiber composites is better than that of copper-doped ZnS particle, which also boast good recycle ability and great stability.
Keywords: polymer chemistry； production hydrogen; photocatalyst; electrospinning; composites

Title: Application development of cyclodextrins and their derivatives on the synthesis process of conductive polymers

Authors: FENG Jiangtao, YAN Wei
PP: 426～430
Abstract: In this paper, the cyclodextrins application in the process of synthesis of conductive polymers, containing the special role of cyclodextrins in the electrochemical and chemical polymerization of conductive polymers and influences on the morphology and the electrochemical properties of propared conductive polymers, have been expatiated detailedly. At the same time, research discoveries in the polymerization of polypyrrole with cyclodextrins as auxiliary reagents are also reviewed simply. These contents can provide some help to research scholars in the fields of cyclodextrins and conductive polymers.
Keywords: polymer chemistry; cyclodextrins; review; polyaniline; polypyrrole; inclusion complexes

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