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    Studies on Synthesis and Biological Activities of Novel Triazole Compounds Containing 1,3-Dioxolane
    XU Liangz-hong, ZHANG Shu-sheng, LI Hui-jing, JIAO Kui
    Chemical Research in Chinese Universities    2002, 18 (3): 284-286.  
    Abstract1077)      PDF(pc) (154KB)(580)       Save
    Nine title compounds were synthesized. Their strucures were identified by means of IR, EA, 1H NMR and MS. The results from the primary biological test show that all the compounds have some activitiies of fungicide and plant growth regulator. When R group is 2,4-Cl2C6H3, compound 2 or compound 4 shows better biological activities.
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    Cited: Baidu(201)
    Studies on Synthesis and Biological Activities of Novel Triazole Compounds Containing Pyrimidine or N,N-Dialkyldithiocarbamate Ring
    XU Liang-zhong, ZHANG Shu-sheng, GAO Hong-rong, JIAO Kui
    Chemical Research in Chinese Universities    2003, 19 (4): 437-441.  
    Abstract1116)      PDF(pc) (727KB)(382)       Save
    Twelve of the title compounds were synthesized. Their structures were identified by means of IR, EA, 1H NMR and MS. The IR spectra clearly show that the absorptions in the regions of 1716-1666 cm-1 and 1505-1499 cm-1 are the characteristic absorption bands for νC=O and νC=N. In the 1H NMR spectra of target compounds(10a-10g), three protons of a -CH-CH2- group present three sets of quartet peaks of the protons. The preliminary bioassays showed that the synthesized compounds exhibited some activities of fungicides and plant growth regulators.
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    Cited: Baidu(191)
    Studies on Synthesis and Biological Activities of Novel Triazole compounds Containing Thiophene Groups
    XU Liang-zhong, ZHANG Shu-sheng, HU Zhi-qiang, JIAO Kui
    Chemical Research in Chinese Universities    2003, 19 (3): 310-313.  
    Abstract993)      PDF(pc) (541KB)(358)       Save
    Fifteen new triazole compounds containing thiophene groups were synthesized and their structures were confirmed by means of 1H NMR, IR, MS spectroscopies and elemental analyses. The preliminary biological tests show that the titled compounds exhibit some activities of fungicides and plant growth regulators.
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    Cited: Baidu(188)
    Electrochemical Study and Application on Shikonin at Poly(diallyldimethylammonium chloride) Functionalized Graphene Sheets Modified Glass Carbon Electrode
    AN Jing, LI Ji-ping, CHEN Wen-xia, YANG Chun-xia, HU Fang-di, WANG Chun-ming
    Chemical Research in Chinese Universities    2013, 29 (4): 798-805.   DOI: 10.1007/s40242-013-2436-9
    Abstract519)            Save

    The electrochemical behaviors of shikonin at a poly(diallyldimethylammonium chloride) functionalized graphene sheets modified glass carbon electrode(PDDA-GS/GCE) have been investigated. Shikonin could exhibit a pair of well-defined redox peaks at the PDDA-GS/GCE located at 0.681 V(Epa) and 0.662 V(Epc)[vs. saturated calomel electrode(SCE)] in 0.1 mol/L phosphate buffer solution(pH=2.0) with a peak-to-peak separation of about 20 mV, revealing a fast electron-transfer process. Moreover, the current response was remarkably increased at PDDA-GS/GCE compared with that at the bare GCE. The electrochemical behaviors of shikonin at the modified electrode were investigated. And the results indicate that the reaction involves the transfer of two electrons, accompanied by two protons and the electrochemical process is a diffusional-controlled electrode process. The electrochemical parameters of shikonin at the modified electrode, the electron-transfer coefficient(α), the electron-transfer number(n) and the electrode reaction rate constant(ks) were calculated to be as 0.53, 2.18 and 3.6 s-1, respectively. Under the optimal conditions, the peak current of differential pulse voltammetry(DPV) increased linearly with the shikonin concentration in a range from 9.472×10-8 mol/L to 3.789×10-6 mol/L with a detection limit of 3.157×10-8 mol/L. The linear regression equation was Ip=0.7366c+0.7855(R=0.9978; Ip: 10-7 A, c: 10-8 mol/L). In addition, the modified glass carbon electrode also exhibited good stability, selectivity and acceptable reproducibility that could be used for the sensitive, simple and rapid determination of shikonin in real samples. Therefore, the present work offers a new way to broaden the analytical application of graphene in pharmaceutical analysis.

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    Cited: Baidu(182)
    Hierarchical Self-organization of Complex Systems
    CHAI Li-he, WEN Dong-sheng
    Chemical Research in Chinese Universities    2004, 20 (4): 440-445.  
    Abstract968)      PDF(pc) (2418KB)(212)       Save
    Researches on organization and structure in complex systems are academic and industrial fronts in modern sciences.Though many theories are tentatively proposed to analyze complex systems, we still lack a rigorous theory on them.Complex systems possess various degrees of freedom, which means that they should exhibit all kinds of structures.However, complex systems often show similar patterns and structures.Then the question arises why such similar structures appear in all kinds of complex systems.The paper outlines a theory on freedom degree compression and the existence of hierarchical self-organization for all complex systems is found.It is freedom degree compression and hierarchical self-organization that are responsible for the existence of these similar patterns or structures observed in the complex systems.
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    Cited: Baidu(172)
    Controlled Radical Polymerization of Styrene in the Presence of Different Copper Complexes and Organic Halides
    CHENG Guang-lou, HU Chun-pu, YING Sheng-kang
    Chemical Research in Chinese Universities    1999, 15 (4): 358-363.  
    Abstract1293)      PDF(pc) (810KB)(322)       Save
    The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2'bipyridine (bpy), 1,10-phenanthroline (phen) or 4,7-diphenyl-1,10-phenanthroline (DPP) ] and R-X (R=trichloromethyl, benzyl or allyl; X=ClorBr) have been studied and examined. In a CuCl/bpy/RCl/St system, a bimodal GPCpeak at the early stage of polymerization was observed, and a concept of multi active species was proposed to explain this phenomenon. In a CuCl/phen (DPP)/RCl/St system, the Mn of polystyrene (PS) increased linearly with St conversion and ln[M]o/[M] also increased linearly with time, indicating the'living' nature of this system. Furthermore, the stability of the propagating active species in a CuBr/phen/RBr/St system is higher than that in the CuBr/phen/RBr/St system.
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    Cited: Baidu(136)
    Preparation, Electrochemical Property and Application in Bulk-modified Electrode of Dawson-type Phosphomolybdate-doped Polypyrrole Composite Nanoparticles
    WANG Xiu-li, ZHAO Hai-yan, WANG Yi-fei
    Chemical Research in Chinese Universities    2006, 22 (5): 556-559.  
    Abstract870)      PDF(pc) (741KB)(389)       Save
    A kind of inorganic-organic hybrid semiconductor composite nanoparticles: Dawson-type phosphomolybdatedoped polypyrrole (P2Mo18-PPy) was designed and prepared using microemulsion oxidation-polymerization at room temperature and characterized by TEM and IR. The P2Mo18-PPy was used as a bulk-modifier to fabricate a chemically modified carbon paste electrode(CPE) by direct mixing, which represents the example of polyoxometalates (POMs)-doped semiconductor polymer nanoparticles modified electrode. Both the advantage of POMs-doped polymer and the surface-renewal property of the CPE were fully utilized. The electrochemical behavior of the P2Mo18-PPy bulk-modified CPE(P2Mo18-PPy-CPE) was investigated with cyclic voltammetry. Three couples of reversible redox peaks were observed in the range from + 800 to 0 mV, which corresponded to the reduction and oxidation through two-, four- and six-electron processes, respectively. The P2Mo18-PPY-CPE showed a high electrocatalytic activity for the reduction of nitrite, which expanded the application of POMs-doped semiconductor polymer nanoparticles.
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    Cited: Baidu(121)
    Graphene-Gold Nanoparticle-modified Electrochemical Sensor for Detection of Kanamycin Based on Target-induced Aptamer Displacement
    ZHENG Jingyi, FENG Rongrong, HE Caimei and LI Xiaoxia
    Chemical Research in Chinese Universities    2018, 34 (6): 952-958.   DOI: 10.1007/s40242-018-8185-z
    Abstract195)            Save
    A highly sensitive and selective label-free electrochemical sensor was developed for the determination of kanamycin. To improve the sensitivity of the electrochemical sensor, graphene-gold nanoparticles were prepared by a one-step electrochemical coreduction process and were modified on the surface of a glassy carbon electrode. The double-stranded DNA(ds-DNA) duplex probe was immobilized onto the graphene-gold nanoparticle-modified electrode. The introduction of target kanamycin induced the displacement of aptamer from the ds-DNA duplex into the solution. Methylene blue(MB) as a redox indicator monitored the current change using differential pulse voltammetry. Under optimal conditions, the designed electrochemical aptasensor exhibited a wide linear range from 0.1 pmol/L to 10 pmol/L with a detection limit of 0.03 pmol/L for kanamycin. The experimental strategy enabled the direct analysis of milk samples, and the results showed high sensitivity and good selectivity.
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    Cited: Baidu(110)
    Preparation and Properties of HBS Lignin from Masson Pine
    CHENG Xian-su, CHEN Wei-jian, CHEN Yun-ping, CHEN Yue-xian, LI Mian-jun, FANG Hua-shu
    Chemical Research in Chinese Universities    2004, 20 (2): 225-228.  
    Abstract1089)      PDF(pc) (194KB)(715)       Save
    In order to establish a new method for making cellulose and lignin from Masson pine, a high boiling solvent (HBS) pulping process with an aqueous solvent of 1,4-butanediol was investigated. Masson pine chips were pulped with a 70%-90% aqueous solution of 1,4-butanediol containing a small amount of a catalyst at 200-220 ℃ for 60-180 min. HBS Masson pine cellulose is suitable for making paper. Water-insoluble HBS lignin was separated from the liquor reaction mixture by water precipitation. The recovered high boiling solvent (RHBS) is able to be recycled as a pulping solvent, indicating that the HBS method is a pulping process of Masson pine which is energy saving, resources saving and pollution free. HBS lignin has a better chemical reactivity and a lower ash content than lignin sulfonate.
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    Cited: Baidu(110)
    TG-FTIR Study on Corn Straw Pyrolysis-influence of Minerals
    YANG Chang-yan, LU Xue-song, LIN Wei-gang, YANG Xue-ming, YAO Jian-zhong
    Chemical Research in Chinese Universities    2006, 22 (4): 524-532.  
    Abstract1087)      PDF(pc) (517KB)(312)       Save
    In order to study the effect of minerals on biomass pyrolysis, experiments on pyrolysis of corn straw with different pretreatment methods were performed by using a thermogravimetric analyzer(TGA) coupled with a Fourier transform infrared(FTIR) spectrometer. The pretreatment methods included water washing and acid washing. The experimental results show that acid washing can remove almost all K+ and 78% of Ca2+, while water washing only removes most of K+. The existence of K+ and Ca2+ obviously favors the formation of compounds containing carbonyl groups and CO2, but it will decrease the yields of compounds containing C-O-C groups. However, the formation of H2O, CO and CH4 are slightly affected by the removal of inorganic ions. With regard to the structure of the metal ions-adsorbed cellulose characterized by IR analysis, it can be considered that there is an "ion force" between metal ions and cellulosic biomass. The results of thermal kinetic analysis show that this force can make the reaction activation energy of the biomass pyrolysis decrease. A new mechanism is proposed for explaining the effect of inorganic ions on cellulose pyrolysis.
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    Cited: Baidu(107)
    Influences of Temperature and Coal Particle Size on the Flash Pyrolysis of Coal in a Fast-entrained Bed
    CUI Li-jie, LIN Wei-gang, YAO Jian-zhong
    Chemical Research in Chinese Universities    2006, 22 (1): 103-110.  
    Abstract1229)      PDF(pc) (436KB)(263)       Save
    The experiments on the flash pyrolysis of a lignite were carried out in a fast-entrained bed reactor as a basic study on a so-called 'coal topping process'. The investigation focused on the effects of pyrolysis temperature and coal particle size on the product distribution and composition. The experimental results show that an increase in the pyrolysis temperature results in a higher yield of gaseous products while a larger particle size leads to a decrease of the liquid yield. An optimum temperature for the liquid yield was found to be 650 ℃. A certain amount of phenol groups was found in the liquid products, which may be used to produce high-valued fine chemicals. The FTIR analyses of the coal and chars show that aliphatic structures in the chars are gradually replaced by aromatic structures with the increasing of pyrolysis temperature and coal particle size. The results of this study provide fundamental data and optimal conditions to maximize light oils yields for the coal topping process.
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    Cited: Baidu(99)
    Kinetics and Mechanism of Dechlorination of o-Chlorophenol by Nanoscale Pd/Fe
    WEI Jian-jun, XU Xin-hua, LIU Yong
    Chemical Research in Chinese Universities    2004, 20 (1): 73-76.  
    Abstract1238)      PDF(pc) (636KB)(627)       Save
    Nanoscale Pd/Fe bimetallic particles were synthesized with an efficient method to dechlorinate o-chlorophenol. The nanoscale Pd/Fe particles were determined by transmission electron microscopy and BET specific surface area analysis. Most of the particles are in the size range of 20-100 nm. The BET specific surface area of synthesized nanoscale Pd/Fe particles is 12.4 m2/g. In contrast, a commercially available fine iron powder(<100 mesh) has a specific surface area of 0.49 m2/g. Batch studies demonstrated that the nanoscale particles can effectively dechlorinate o-chlorophenol. The dechlorination reaction takes place on the surface of synthesized nanoscale Pd/Fe bimetallic particles in a pseudo-first order reaction. The surface-area-normalized rate coefficients(kSA) are comparable to those reported in the literature for chlorinated ethenes. The observed reaction rate constants(kobs) are dominated by the mass fraction of Pd and the mass concentration of the nanoscale Pd/Fe particles.
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    Cited: Baidu(97)
    Synthesis and Characterization of Microcapsules with Chlorpyrifos Cores and Polyurea Walls
    ZHANG Qiang, ZHANG Pei-pei, JIAO Qing-ze
    Chemical Research in Chinese Universities    2006, 22 (3): 379-382.  
    Abstract1269)      PDF(pc) (333KB)(491)       Save
    Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interfacial polycondensation reaction.The products were characterized by means of Fourier transform infrared spectrometry, 13C NMR spectrometry and 31P NMR spectrometry.The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated.The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28.13 μm.These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.
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    Cited: Baidu(90)
    Studies on Adsorption Behavior and Mechanism of Copper(Ⅱ) onto Amino Methylene Phosphonic Acid Resin
    XIONG Chun-hua, WANG Yong-jiang, SHI Lin-mei
    Chemical Research in Chinese Universities    2003, 19 (3): 366-369.  
    Abstract1101)      PDF(pc) (673KB)(286)       Save
    The adsorption behavior and the mechanism of a novel chelate resin, amino methylene phosphonic acid resin(APAR) for Cu(Ⅱ) were investigated. Cu(Ⅱ) was quantitatively adsorbed by APAR in the medium of pH=4.09. The statically saturated adsorption capacity is 181 mg/(g resin). Cu(Ⅱ) adsorbed on APAR can be eluted by 1.0-3.0 mol/L HCl. The rate constant is k298=5.58×10-5 s-1. The adsorption of Cu(Ⅱ) on APAR follows the Freundlich isotherm. The ΔH of the adsorption is 3.91 kJ/mol. The apparent activation energy is Ea=21.4 kJ/mol. The coordination molar ratio of APAR to Cu(Ⅱ) is 1/1. It is shown that the nitrogen and the oxygen atoms in the functional group of APAR coordinate to Cu(Ⅱ).
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    Cited: Baidu(88)
    Highly Sensitive Spectrofluorimetric Determination of Trace Amounts of Indium(Ⅲ) with Salicylaldehyde Salicyloylhydrazone
    HAN Fang, WANG Hongjian, TANG Bo
    Chemical Research in Chinese Universities    2002, 18 (2): 183-188.  
    Abstract926)      PDF(pc) (778KB)(306)       Save
    The fluorescent reaction of salicylaldehyde salicyloylhydrazone (SASH) with indium (Ⅲ) was studied in detail. Based on this chelation reaction, a sensitive spectrofluorimetric method was developed for the determination of indium in a water-ethanol(volume ratio 3: 7) medium at pH 4.0. Under the condition, the InSASH complex displays an excitation and emission maxima at 396 and 461 nm, respectively. The linear range of the method is from 4. 7 to 1000 ng/mL and the detection limit is 0. 94 ng/mL. The molar ratio of indium to the reagent is 1 : 1. The interferences of other ions were studied. The method was successfully applied to the determination of indium in the chemical reagents of lead, tin, zinc, zinc chloride and geological samples by standard addition method.
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    Cited: Baidu(88)
    Isolation and Spectroscopic Characterization of Protonated Mixed [Tetrakis (4-pyridyl)porphyrinato] (phthal ocyaninato)Rare Earth (Ⅲ)Double-decker Compounds
    JIANG Jian-zhuang, LIU Wei, SUN Xuan, ZHANG Xian-xi, NG Dennis K. P.
    Chemical Research in Chinese Universities    2001, 17 (2): 134-142.  
    Abstract1016)      PDF(pc) (299KB)(247)       Save
    The treatment of tetrakis(4-pyridyl)porphyrin H2TPyP with a hydrated rare earth (Ⅲ) acetylacetonate RE(acac)3·nH2O (RE=Y, Eu, Gd) in 1,2,4-trichlorobenzene (TCB) pro duced a monomeric porphyrinato rare earth compound RE(TPyP)acac, which further reacted with dicyanobenzene in amyl alcohol in the presence of 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU), giving HRE(TPyP)(Pc) in a good yield. Upon exposure to air, part of the protonated mixed double-deckers in CHCl3 solutions converted slowly to the corresponding neutral complexes RE(TPyP) (Pc). These protonated complexes were characterized by means of UV-Vis, IR, NMR, mass spectroscopies. The quaternarization of these protonated mixed double-deckers with methyl iodide produced the salts of tetramethylated cations [HRE (TMPyP)(Pc)]4+.
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    Cited: Baidu(88)
    Preparation and Catalytic Application of Novel Water Tolerant Solid Acid Catalysts of Zirconium Sulfate/HZSM-5
    JIANG Ya-jie , JUAN Joon Ching , MENG Xiu-juan , CAO Wei-liang , YARMO Mohd Ambar , ZHANG Jing-chang
    Chemical Research in Chinese Universities    2007, 23 (3): 349-354.  
    Abstract1606)            Save
    Esterification of acrylic acid(AA) to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorption, TGA-DTA, XPS, and ammonia adsorption FTIR. The effects of Si/Al ratio, zirconium sulfate(ZS) loading on HZSM-5 and calcination temperature on the esterification were investigated. When 20%(mass fraction) ZS is loaded on HZSM-5, the conversion of AA reaches 100%. XRD analysis indicates that ZS is highly dispersed on HZSM-5 because no crystalline structure assigned to ZS is found. Catalytic activity and hydrophobicity of ZS supported on HZSM-5 are higher compared with those of parent ZS or HZSM-5. Results show that this kind of novel catalysts is an efficient water tolerant solid acid catalyst for esterification reactions.
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    Cited: Baidu(88)
    Covalent Immobilization of Lipase on Poly (acrylonitrile-co-maleic acid) Ultrafiltration Hollow Fiber Membrane
    YE Peng, XU Zhi-kang, WU Jian, DENG Hong-tao, SETA Patrick
    Chemical Research in Chinese Universities    2005, 21 (6): 723-727.  
    Abstract1262)      PDF(pc) (383KB)(263)       Save
    Lipase from Candida rugosa was covalently immobilized on the surface of an ultrafiltration hollow fiber membrane fabricated from poly (acrylonitrile-co-maleic acid) (PANCMA) in which the carboxyl groups were activated with 1-ethyl-3-(dimethylaminopropyl) carbodiimide hydrochloride (EDC) and dicyclohexyl carbodiimide (DCC)/N-hydroxyl succinimide(NHS), respectively.The properties of the immobilized lipase were assayed and compared with those of the free enzyme.The maximum activities were observed in a relatively broader pH value range at high temperatures for the immobilized lipase compared to the free one.It was also found that the thermal and pH stabilities of lipase were improved upon immobilization and at 50 ℃ the thermal inactivation rate constant values are 2.1×10-2 for the free lipase, 3.2×10-3 for the immobilized lipase on the EDC-activated PANCMA membrane and 3.5×10-3 for the immobilized lipase on the DCC/NHS-activated PANCMA membrane, respectively.
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    Cited: Baidu(84)
    Novel Strategy for Synthesis of High Quality CdTe Nanocrystals in Aqueous Solution

    YAN Yu-xi, MU Ying, FENG Guo-dong, ZHANG Lei, ZHU Lin-lin, XU Ling, YANG Rui , JIN Qin-han

    Chemical Research in Chinese Universities    2008, 24 (1): 8-14.  
    Abstract1634)            Save
    A novel aqueous route for the synthesis of high-quality CdTe nanocrystals(NCs) is presented in this article. With both glutathione(GSH) and cysteine[n(GSH):n(cysteine)=1:3] as stabilizers, high-quality CdTe NCs with controllable photoluminescence(PL) wavelength from 500 to 630 nm can be prepared within 4 h. As-prepared CdTe NCs show higher photoluminescence quantum yields(PLQY) compared with CdTe NCs prepared via other aqueous methods. When the fluorescent emission peak appeared in orange-red window, the PLQY reaches 70% or above at room temperature without any post-preparative treatment.
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    Cited: Baidu(82)
    Syntheses, Characterization and Anti-HIV Activity of Charge Transfer Heteropolycomplexes
    LIU Shu-xia, LI Yang-guang, HAN Zeng-bo, HUANG Ru-dan, WANG En-bo, ZENG Yi, LI Ze-lin
    Chemical Research in Chinese Universities    2001, 17 (2): 127-133.  
    Abstract946)      PDF(pc) (480KB)(171)       Save
    Each of Keggin type heteropolytungstosilicic and heteropolytungstogermanic acids reacted with 8-quinolinol, p-aminodimethylaniline and pyridine, respectively, yielding six charge trans fer heteropolycomplexes(CTHPCs), which were purified and characterized by elemental analy sis, IR, UV and 183W NMR. The anti-HIV-1 activities of CTHPCs were evaluated by ELISA of HIV-P24 antigen. The toxicity against MT-4 cells was measured by MTT. The results show that median inhibitory concentration(IC50) for each CTHPC to inhibit HIV-P24 antigen in cell culture was lower than 5 g/mL, while median toxicity concentration (IC50) against MT-4 cells was higher than 268 g/mL. The following mechanisms might be considered for their anti-HIV 1 activity, namely, (1) inhibiting the penetration of HIV-1 virus into target cells for it can blockade CD4 receptor of MT-4 cells and (2) inhibition of syncytium formation.
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    Cited: Baidu(81)
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Jihong YU
ISSN 1005-9040
CN 22-1183/O6
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