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Paederia foetida- a promising ethno-medicinal tribal plant of northeastern India

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Journal of Forestry Research 2013年第4期24卷 801-808页

作者： Silpi Chandadept.of Pharmacy Jaypee University of Information Technology Indira P Sarethy Biplab De Kuldeep Singh dept.of Biotechnology Jaypee Institute of Information Technology dept.of pharmaceutical Science Assam University dept.of Pharmacy Jaypee University of Information Technology

The northeastern region of India constitutes one of the biodi- versity hotspots of the world. The ethnic groups inhabiting this region practice their distinctive traditional knowledge systems using biodiver- sity for food, shelter and healthcare. Among the less-studied plants, Paederia foetida has been used by various ethnic tribes as food and medicine. Many of its therapeutic properties relate to the gastrointestinal system and suggest its potential utility for gastrointestinal ailments. This is a review of the ethnobotanical uses, phytochemistry and therapeutic properties of P. foetida compiled from various reports. P. foetida is promising as a remedy for life-style related conditions, especially treat- ment of ulcers. Its utility highlights the need for proper evaluation of tribal plants as medicines and the species could be considered for devel- opment of new drugs.

关键词： Paederia foetida Tribal medicine ethnobotany phyto-chemistry therapeutic ulcer

Enhanced lithium storage of mesoporous vanadium dioxide(B) nanorods by reduced graphene oxide support

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Journal of Energy chemistry 2018年第1期27卷 183-189页

作者： Thummala Jayalakshmi Kottam Nagaraju Ganganagappa Nagaraju dept.of chemistry Siddaganga Institute of Technology(Affiliated to Visvesvaraya Technological UniversityBelgaum) dept.of chemistry M.S.Ramaiah Institute of Technology(Affiliated to Visvesvaraya Technological UniversityBelgaum)

A facile synthesis of vanadium oxide with reduced graphene oxide（rGO） is developed and used as cathode material for lithium ion batteries. VO_2（B） nanorods and VO_2（B）-rGO composite were prepared by a hydrothermal method using NaVO_3 precursor and sodium oxalate as a reducing agent. The monoclinic phase and nanorod like morphology of synthesized materials were confirmed by XRD, SEM, and TEM respectively. The electrochemical properties of samples were investigated at 1.5–4.0 V, and 0.1 C rate,and the VO_2（B） nanorods exhibit reversible capacity of about 159 mAh g^（-1）, whereas VO_2（B）-rGO exhibits 274 mAh g^（-1）. The reasonable discharge capacities were obtained at high rates. The enhanced performance in electrical energy storage system reveals the effectiveness of rGO in the composite, as it enhances the conductive electron pathway to overcome the intrinsic limits of single phase VO_2（B）.

关键词： VO2(B) and VO2(B)-rGO compositeNanorodsMesoporousLithium-ion battery

Synthesis and kinetics of 2-chloro-4,6-dinitroresorcinol

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Journal of Harbin Institute of Technology(New Series) 2008年第4期15卷 518-520页

作者：史瑞欣黄玉东 dept.of chemistry and Chemical Engineering Northeast Forestry University dept.of Applied chemistry Harbin Institute of Technology

2-chloro-4,6-dinitroresorcinol was synthesized from 4,6-dinitro-1,2,3-trichlorobenzene by *** ultraviolet spectrophotometry was used to measure the absorbency of the hydrolysis mixture under different temperatures and periods of *** kinetic calculation,it is shown that when the reaction temperature is in the range of 343.15 K to 358.15 K,the reaction is consistent with the secondary apparent dynamic model,the apparent activation energy is 200.11 kJ/mol and the expression of kinetic parameter k is 3.761×1028exp(-2.001×105/RT).The reaction is controlled by the course of chemical reactions.

关键词： 2-chloro-4,6-dinitroresorcinol synthesis kinetics

DFT studies on the SCR reaction mechanism of nitrogen monoxide with propylene catalyzed by copper oxide

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Journal of Harbin Institute of Technology(New Series) 2007年第3期14卷 389-391页

作者：田英许晶赵景祥 dept.of chemistry Harbin Normal University

The SCR reaction mechanism of NO with C3H6catalyzed by CuO was studied by the method of Density Functional Theory(DFT)at the B3LYP/LanL2DZ *** optimized geometries of the stationary points on the potential surface were obtained and the transition state was confirmed by IRC and vibration *** activation energy was calculated being 34.26 kJ/*** was shown that propylene reacted firstly with Cu forming intermediate,and then nitrogen monoxide immediately reacted with the intermediate to be *** was proved to be a direct interaction mechanism.

关键词： catalyst CuO propylene nitrogen monoxide immediate reaction mechanism DFT/B3 LYP calculation

AN AB INITIO N_(2)-H_(2)O POTENTIAL FOR COMPUTER SIMULATIONS

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Chinese Chemical Letters 1995年第2期6卷 169-172页

作者： Jian De GU Jing Lai ZHANG An Min TIAN Guo Sen YAN chemistry dept.of Sichuan University Chengdu 610064

N2-H2O system was studied by ab initio SCF calculations with a 6-31G** basis set. The results were fitted to an analytical funotion assuming psirwise additivity for the interaction between individual centres. The analytical functions were Lennard-Jones 10-6 and exponential form. A satisfactory fitting result was achieved by the simulated anneal algorithm. Special care was paid to repulsive region, which gives the important contribotions to the formation of the first solvation shell of apoler solutes.

关键词： ?

Crystallization process of 2-chloro-4,6-diaminoresorcinol

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Journal of Harbin Institute of Technology(New Series) 2009年第4期16卷 532-536页

作者：宋元军黄玉东林宏黎俊王卓 dept.of Applied chemistry Harbin Institute of Technology

In order to get 2-chloro-4,6-dinitroresocinol(CDNR) with high purity,which influences the synthesis of 4,6-diaminoresorcinol dihydrochloride,the solubility of CDNR in various solvents was measured by laser method and ethanol was chosen as the *** recrystallization process of CDNR was investigated and crystallizing parameters such as cooling rate,temperature and time were *** results show that the time and temperature of crystallization greatly affect the yield and a higher yield can be received at-8 ℃ for 5 *** cooling rate is helpful to the crystallization of CDNR,and the mechanical stirring or ultrasonic treatment can increase the yield and the purity of CDNR.

关键词： 2-chloro-4,6-dinitroresocinol recrystallization yield solubility

Preparation of superabsorbent by graft copolymerization of acrylic acid onto corn starch using K_2S_2O_8 and rare earths as initiators

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Journal of Harbin Institute of Technology(New Series) 2008年第6期15卷 831-834页

作者：白永平李卫东冯立群赵超 dept.of Applied chemistry Harbin Institute of Technology

K2 S2 O8 and rare earths （RE） were used as initiators to prepare superabsorbents by graft copolymerization of acrylic acid （ AA ） onto corn starch. The effects of monomer concentration, initiator K2 S2 O8 concentration, cross-linker concentration, reaction temperature and the concentration ratio of RE and K2 S2O8 on the graft copolymerization were studied in terms of the water absorption capacity of superabsorbents. Results indicate that the optimum conditions obtained for the grafting of AA onto 5g starch are as follows： AA of 75. 773 g/L, K2S20s of 0. 437 g/L, RE of 0. 874 g/L, cross-linker of 0. 381 g/L and temperature of 70 ℃. The maximum water absorption capacity obtained is 740 g/g. The new method of graft polymerization is easily proceeded and controlled. The graft copolymers were characterized by infra-red spectroscopy, scanning electron microscopy and TG. Results characterized by IR and SEM give strong evidence for grafting of AA onto corn starch, and those characterized by TG reveal that the grafting of AA improves the theimostability of corn starch.

关键词： superabsorbent graft copolymerization starch acrylic acid rare earths

SYNTHESIS AND CHARACTERIZATION OF NOVEL OPTICALLY ACTIVE POLY(AMIDE-IMIDE)S AND POLY(ESTER-IMIDE)S CONTAINING CALIX[4]ARENE AND AMINO ACID UNITS WITH BINDING ABILITY TOWARDS ALKALI METAL AND TOXIC HEAVY METAL CATIONS

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Chinese Journal of Polymer Science 2010年第5期28卷 731-743页

作者： Abdol-reza Hajipour Sakineh Habibi Arnold E.Ruoho dept.of Pharmacology University of WisconsinMedical SchoolMadison53706-1532WIUSA pharmaceutical Research Laboratory College of ChemistryIsfahan University of TechnologyIsfahan 84156IR Iran

A novel calix[4]arene derivative 2 with amino functional groups at the lower rim was first prepared via introduction of nitro functional groups and amination of the dinitro derivative of calix[4]arene. The optically active monomers were synthesized by dehydration of L-leucine （and L-isoleucine） and 3,3＇,4,4＇-benzophenonetetracarboxylic- 3,3＇,4,4＇-dianhydride （3） followed by reaction with thionyl chloride to form 5a and 5b. Two methods, polymerization under microwave irradiation and solution polymerization in CH2Cl2/TEA, were then employed to carry out the condensation polymerization of 2 with the optically active monomers 5a and 5b, respectively. The polymerization conditions affected the kind of resulting polymers, poly（amide-imide）s （PAIs） 6a and 6b and poly（ester-imide）s （PEIs） 6a＇ and 6b＇ were obtained selectively in good yields and moderate inherent viscosities. Sorption-extraction experiments were carried out using cram picrate extraction method and verified good binding ability of the resulting calixarene-based polymers towards silver, alkali metal and toxic heavy metal cations. Also thermogravimetric analysis indicated that the resulting PAIs and PEIs were thermally stable.

关键词： Condensation polymerization Ionophores Optically active Toxic heavy metals Polymeric calixarenes Thermal stability.

Synthesis,Characterization and Crystal Structure of a Three-dimensional Coordination Polymer {[Cd(1,5-nds)(Him)_2(H_2O)]·2H_2O}n

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Chinese Journal of Structural chemistry 2008年第12期27卷 1533-1537页

作者：钱保华马卫兴许兴友陆路德杨绪杰汪信 Materials chemistry Laboratory Nanjing University of Science & Technology dept.of Chemical Technology Huaihai Institute of Technology

A novel cadmium（Ⅱ） coordination polymer {[Cd（1,5-nds）（Him）2（H2O）]·2H2O}n （1,5-nds = naphthalene-1,5-disulfonate and Him = imidazole） was synthesized based on the reaction of cadmium oxide and 1,5-naphthalenedisulfonic acid firstly, and then mixed with imidazole in methanol medium. Its structure was characterized by elemental analysis, IR and TGA, respectively. The crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1, with a = 8.5420（10）, b = 10.2570（10）, c = 13.361（2） A, α = 100.704 （2）, β = 100.195（2）, γ = 108.873（3）°, C16H20Cd N4O9S2, Mr= 588.91, V = 1.0524（2） nm^3, Dc = 1.858 g/cm^3, Z = 2, F（000） = 592, β^ = 1.294 mm-1, R = 0.0397 and wR = 0.1007 for 3180 observed reflections （Ⅰ〉 2σ（Ⅰ））. Structural analysis shows that the cadmiun atom is coordinated with four oxygen atoms from three 1,5-nds and one water molecule together with two nitrogen atoms from two imidazoles, giving a distorted octahedral coordination geometry. The molecules are linked to form a two-dimensional coordination polymer based on bridging ligands of naphthalene- 1,5-disulfonate anions, the sheets of which are then interacted via hydrogen bonds, leading to a three-dimensional network structure.

关键词： cadmium(Ⅱ) coordination polymer crystal structure naphthalene-1,5-disulfonate anion imidazole