Table of Content

24 December 2004, Volume 20 Issue 6

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Articles

Preparations of Pure Alkaline Earth Molybdate Phases from Single Molecular Precursors

JIANG Ya-qi, ZHAO Hong, FANG Zhi-min, WAN Hui-lin, XIONG Ming, ZHOU Zhao-hui

2004, 20(6):  675-680. 

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The pure phases of alkaline earth molybdates MMoO₄, where M=Mg, Ca, Sr or Ba, were synthesized via the calcination of the related citrato oxomolybdate complexes. The mixed metal oxides can be highly dispersed at the atomic level due to the existence of uniform citrato oxomolybdenum precursors in definite composition. The complexing effect helps to produce the fine-grained oxides with particle size in the ultrafine scale(<100 nm) at heat-treatment temperatures below 500 ℃. The structures of the precursor complexes and the finally heat-treated particles were studied by means of IR, XRD, DSC, DTA and TG techniques. The morphologies of the particles were observed by using the SEM technique. The average particle sizes were calculated to be in the range of 30_50 nm based on X-ray diffraction line-broadening and SEM images, indicating the poor conglomeration of crystallite at low temperatures.

Synthesis, Structure and Third-order Non-linear Optical Properties of Tungsten Dioxo Complex with 8-Hydroxyquinoline Ligand WO₂(C₉H₆NO)₂

LI Yong, LU Jing, XU Ji-qing, CUI Xiao-bing, SUN Ying-hua, LI Ke-chang, PAN Ling-yun, BIE Hai-ying

2004, 20(6):  681-684. 

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Tungsten dioxo complex WO₂(C₉H₆NO)₂ was obtained via the low temperature solid-state reaction of(NH₄)₂WS₄, 8-hydroxyquinoline(8-hq) and(CH₃)₄NI, and it was characterized by means of elemental analyses, IR spectroscopy and X-ray diffraction analysis. The crystal of the title compound belongs to monoclinic, space group C2/c, with the crystal cell parameters: a=1.3316(3) nm, b=0.94444(19) nm, c=1.3485(3) nm, β=109.66(3)°, V=1.5970(6) nm³, Z=6. The title compound possesses a supramolecular structure formed through hydrogen bonds and π-π stacking interactions. The third-order non-linear optical(NLO) properties of the title compound were also investigated. The third-order non-linear absorption coefficient α₂ and refractive index n₂ are 0.85×10^-11 m/W^-1 and -1.5×10^-19 m²/W, respectively. The third-order non-linear susceptibility χ⁽³⁾ is 3.03×10^-13 esu for 3.8×10^-5 mol/L sample concentration.

Dispersion and Structure Studies of Molybdenum Oxide on Anatase TiO₂

ZI Feng-lan, GUO Hong-you, WU Nian-zu, XIE Ya-ning, HU Tian-dou

2004, 20(6):  685-689. 

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X-ray photoelectron spectroscopy(XPS) and extended X-ray absorption fine structure(EXAFS) were used to characterize the structure of the mixture of molybdenum oxide and anatase calcined at 723 K. The results indicate that molybdenum oxide can disperse onto the surface of anatase(TiO₂) and the dispersion threshold is 11.2 mg in per gram of MoO₃ or 4.8 Mo atoms/nm² TiO₂. When the content of MoO₃ is below the dispersion threshold, MoO₃ species is in highly dispersed state interacting strongly with TiO₂ support and in discrete tetrahedral coordination, [MoO₄], on the surface of TiO₂. When the MoO₃ loading is above this value, MoO₃ exists in both dispersed phase and crystalline phase. MoO₃ in dispersed phase is still a discrete [MoO₄] tetrahedron; MoO₃ in crystal phase is in octahedral coordination.

Electrochemical Determination of Alkaline Phosphatase in Human Serum by Differential Pulse Voltammetry

SUN Wei, JIAO Kui, WANG Hai-yu, LU Lu-de

2004, 20(6):  690-693. 

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Differential pulse voltammetry(DPV) was applied to the determination of alkaline phosphatase(ALP) activity in human serum with phenyl phosphate as the substrate. Phenyl phosphate can enzymatically be hydrolyzed to produce phenol which is quantified by DPV at +660 mV(vs.Ag/AgCl) in the concentration range of 2.0_100 μmol/L. The standard curve for ALP is linear over the range from 0.06 to 1000 U/L with a relative standard deviation of 3.0%. The conditions for the enzymatic reaction and voltammetric detection were optimized and the kinetic constants were also examined.The human serum samples were tested by this method and the results were in good agreement with those obtained by the routine p-nitrophenyl phosphate spectrophotometric method.

Electrochemical Studies of Eight New Divalent Transition Metal Benzenesulphonate Ternary Complexes with 1,10-Phenanthroline

LU Yao, GUO Li-ping, MA Jian-fang, YANG Jin, WU Dong-mei

2004, 20(6):  694-697. 

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The electrochemical properties of eight new divalent transition metal benzenesulphonate complexes with 1,10-phenanthroline in different solvents and supporting electrolytes were investigated by means of cyclic voltammetry(CV). Based on the CV data the influences of various coordination modes on the electrochemical behavior of the complexes were discussed. The diffusion coefficient D_c and rate constant k_s of those complexes in DMF systems were estimated according to CV and the results show that these processes were all quasi-reversible.

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

REN Shou-xin, GAO Ling

2004, 20(6):  698-702. 

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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.

Microwave-assisted Extraction of Rutin and Quercetin from Flos Sophorae

LI Min-jing, YOU Jing-yan, YAO Shuang, DING Lan, LIU Zhong-ying, ZHANG Han-qi

2004, 20(6):  703-706. 

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Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction(SMOBE). The third procedure was microwave resonant cavity dynamic extraction(MRCDE). The results obtained by the three microwave-assisted extraction procedures were compared with those obtained by using traditional Soxhlet extraction. The results indicate that the MAE not only took a shorter time, but also simplified the procedure, and made the extraction a higher yield. At the same time the results obtained by the three MAE procedures were also compared with each other.

Isolation and Extraction of Total Flavonoids from Epimedium Koreanum Nakai by Supercritical Fluid Extraction

LIU Chun-ming, ZHAO Xue-liang, LIU Zhi-qiang, XING Jun-peng

2004, 20(6):  707-710. 

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In the present paper is reported the method for the isolation and extraction of total flavonoids of Epimedium Koreanum Nakai by means of supercritical fluid extraction(SFE). By examining pressure, temperature, amounts of modifier and extraction time, the optimized condition of SFE is confirmed as 30 MPa and 60 ℃, with 70% ethanol as the modifier. The samples were statically extracted for 30 min, followed by dynamic extraction for 120 min at a flow rate of 6 mL/min. The quantitative analysis of total flavonoids was performed by UV-Vis spectrophotometry. Compared with the conventional method, the SFE method is more efficient, more rapid and more friendly environmentally.

Application of Catalytic Wet Air Oxidation to Treatment of Landfill Leachate on Co/Bi Catalyst

LI Hai-sheng, LIU Liang, ZHANG Rong, DONG De-ming, LIU Hong-liang, LI Yu

2004, 20(6):  711-716. 

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Catalytic wet air oxidation(CWAO) was employed to reduce the organic compounds in landfill leachate and the effects of temperature, oxygen pressure, catalyst dosage, and concentration of the organic compounds on the TOC and COD_Cr removal rates were studied. The degradation kinetics of landfill leachate was also investigated and an exponential experiential model consisting of four influential factors was established to describe the reduction of the organic compounds in the landfill leachate. Meanwhile, the GC-MS technique was used to detect the components of the organic intermediates for the inference of the decomposition mechanisms of the organic compounds in landfill leachate. The results reveal that the reaction temperature and the catalyst dosage are the most important factors affecting the degradation reaction of the organic compounds and that the principal intermediates confirmed by GC-MS are organic acids at a percentage of more than 88% with no aldehydes or alcohols detected. The decomposition mechanisms of the organic compounds in landfill leachate were inferred based on the GC-MS information as follows: the activated gas phase O₂ captured the hydrogen of the organic pollutants to produce free radicals, which then initiated the catalytic reaction. So most of the organic compounds were oxidized into CO₂ and H₂O ultimately. In general, catalytic wet air oxidation over catalyst CO₃O₄/Bi₂O₃ was a very promising technique for the treatment of landfill leachate.

Effect of Preparation Methods of Bi₂O₃ Nanoparticles on their Photocatalytic Activity

DING Peng, DU Yao-guo, XU Zi-li

2004, 20(6):  717-721. 

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Bi₂O₃ nanoparticles were prepared by means of ammonia precipitation, polyol mediated methods and microemulsion chemical method. The structure and properties of the as-prepared nanoparticles, having been submitted to a heat-treatment test at 750 ℃, were characterized by means of XRD, BET, XPS and UV-Vis absorption techniques. The photocatalytic oxidation reactions of benzene, toluene and xylene were used as the model reaction to measure the photocatalytic activity of Bi₂O₃ nanoparticles, respectively. The results show that the crystallite size of Bi₂O₃ prepared with different methods and calcined at 750 ℃ were 50.6, 38.5 and 31.5 nm, respectively. The photocatalytic activity of Bi₂O₃ nanoparticles prepared with the microemulsion chemical method was higher than that of the particles prepared with the polyol mediated method; and that of the particles prepared with the micromulsion chemical method was the highest among the three. The degradation rates of the three pollutants xylene, toluene and benzene decreased in sequence.

Synthesis and Crystal Structure of 5-Nitro-4-salicylideneamino-3-methyl-1,2,4-triazol-5-thione

WEN Li-rong, LI Ming, WANG Shu-wen, ZHANG Shu-sheng, LI Xue-mei, OUYANG Ping-kai

2004, 20(6):  722-724. 

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The crystal structure of 5-nitro-4-salicylideneamino-3-methyl-1,2,4-triazole-5-thione ([C₁₀H₉N₅O₃S]·HCON(CH₃)₂, M_r=352.38)(CCDC No. 216094) was determined by the single crystal X-ray diffraction method. The crystal belongs to a triclinic system, the space group is P1 with unit cell constants a=0.6113(2) nm, b=1.0836(4) nm, c=1.3132(5) nm, α=74.523(7)°, β=117.68(3)°, γ= 79.769(7)°, V=0.8245(5) nm³, Z=2, D_c=1.419 g/cm³, μ=0.228 mm^-1, F(000)=368, R and wR are 0.0579 and 0.1040, respectively, beasd on 3348 unique reflections of which 1925 reflections were observed[I>2σ(I)]. The results indicate that the title compound can be assigned to the thione tautomeric form rather than the thiol tautomeric form. It contains a five membered triazole ring and a phenyl ring with a dihedral angle of 4.35°. The intermolecular hydrogen bond N3_H3…S1, O1_H1…O4 can be observed.

Synthesis and Crystal Structure of a New Dinuclear Manganese(Ⅱ) Manganese(Ⅲ) Complex of a Macrocyclic Ligand

JIAN Fang-fang, XIAO Hai-lian, XU Liang-zhong, PANG Lei

2004, 20(6):  725-728. 

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A mixed-valence dinuclear manganese complex, [Mn^ⅡMn^ⅢL](ClO₄)·1/2MeOH, where L is a macrocyclic ligand derived from the cyclocondensation of sodium 2,6-diformyl-4-methylphenolate with N,N-bis(2-aminoethyl)-2-hydroxybenzyl amine, was obtained and its structure was determined by X-ray diffraction. The orange crystal is a monoclinic system with space group P2₁/c and lattice parameters a=1.1617(4), b=1.4005(3), c=1.4641(3) nm, β=113.03(2)°, and Z=2. The crystal structure shows that each pendant-arm is bonded in a bidentate fashion to the adjacent metal atom and that both the arms are on the same side of the macrocycle. The two Mn atoms are bridged by two μ₂-phenoxy oxygen atoms of the tetra-imine macrocycle, and each Mn atom, locating in a trigonal prismatic coordination environment(N₃O₃), is six-coordinated by the two imine nitrogen atoms, one tertiary nitrogen atom and a pendant phenol moiety apart from the two oxygen atoms.

Studies on Fragmentation Regularity of 5-Methoxycarbonyl-4-substituted-6-methyl-3,4-dihydropyrimidin-2(1H)-ones by Time-of-flight Mass Spectrometry

LI Qian-rong, SALEHI Hojatollah, YIN Hao, Qing-xiang

2004, 20(6):  729-733. 

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The electron impact time-of-flight(TOF) mass spectra of the title compounds were studied to establish their fragmentation processes. With the high resolution of the TOF instrument, the exact mass for each fragment was determined. These data were used to infer the molecular formulas and the elemental compositions for all the molecular ions and fragments through software interpretation. By further applying the fragmentation regularity, the majority of ions were fully assigned. The main fragmentation pathways of the title compounds include the formation of molecular ions by the loss of R¹ groups in the 4-position and the ester groups in the 5-position. The formed ion can be further fragmented by the elimination of MeOH.

A Convenient and Practical Prepapation of Acetylphenyl Boronic Acids

CHAO Jian-ping, WANG Wei, WU Wen-qun, LUO Xuan-de, LING Yang-zhi

2004, 20(6):  734-737. 

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A practical and scalable synthesis route of acetylphenylboronic acids is described. Bromoacetophenones(compounds 3a, 3b) were ketalized with ethylene glycol and triethyl orthoformate to give bromo ketals(compounds 4a_4c) in 60_80% yields. Compounds 4a_4b were treated with a Grignard reagent and then exchanged with borate to give p^- and m^- acetylphenyl boronic acids(compounds 5a and 5b) in 80% and 56% yields, respectively. The o^-form(compound 5c) was obtained in 61% yield via the BuLi method.

A High-affinity Activator of G551D-CFTR Chloride Channel Identified By High Throughput Screening

ZHAO Lu, HE Cheng-yan, LIU Yan-li, ZHOU Hong-lan, ZHOU Jin-song, SHANG De-jing, YANG Hong

2004, 20(6):  738-742. 

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A stably transfected CHO cell line coexpressing G551D-CFTR and iodide-sensitive yellow fluorescent protein mutant EYFP-H148Q-I152L was successfully established and used as assay model to identify small-molecule activators of G551D-CFTR chloride channel from 100000 diverse combinatorial compounds by high throughput screening on a customized Beckman robotic system. A bicyclooctane compound was identified to activate G551D-CFTR chloride channel with high-affinity(K_d=1.8 μmol/L). The activity of the bicyclooctane compound is G551D-CFTR-specific, reversible and non-toxic. The G551D-CFTR activator may be useful as a tool to study the mutant G551D-CFTR chloride channel structure and transport properties and as a candidate drug to cure cystic fibrosis caused by G551D-CFTR mutation.

A Class of High-affinity Bicyclooctane G551D-CFTR Activators Identified by High Throughput Screening

HE Cheng-yan, ZHAO Lu, LIU Yan-li, XU Li-na, SHANG De-jing, YANG Hong

2004, 20(6):  743-746. 

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The glycine-to-aspartic acid missense mutation at the codon 551(G551D) of the cystic fibrosis transmembrane conductance regulator(CFTR) is one of the five most frequent cystic fibrosis(CF) mutations associated with a severe CF phenotype. To explore the feasibility of pharmacological correction of disrupted activation of CFTR chloride channel caused by G551D mutation, we developed a halide-sensitive fluorescence miniassay for G551D-CFTR in Fisher rat thyroid(FRT) epithelial cells for the discovery of novel activators of G551D-CFTR. A class of bicyclooctane small molecule compounds that efficiently stimulate G551D-CFTR chloride channel activity was identified by high throughput screening via the FRT cell-based assay. This class of compounds selectively activates G551D-CFTR with a high affinity, whereas little effect of the compounds on wildtype CFTR can be seen. The discovery of a class of bicyclooctane G551D-CFTR activators will permit the analysis of structure-activity relationship of the compounds to identify ideal leads for in vivo therapeutic studies.

Effects of Ga-flux on Optical Properties and Morphology of GaN Grown via Molecular Beam Epitaxy

YANG Jing-hai, GONG Jie, FAN Hou-gang, YANG Li-li, ZHANG Yong-jun, Zsebk O., CHEN Gang

2004, 20(6):  747-750. 

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A series of GaN layers was grown on sapphire (0001) substrates under various growth conditions by means of the molecular beam epitaxy(MBE) method, the optical characteristics and surface morphologies of the samples were studied. The results show that the line width of the GaN emission gradually decreases and the peak shifts under the Ga-rich condition by increasing the Ga-flux on keeping all other growth conditions unchanged. It has been also found that the resulted morphology is directly related to the Ga-flux.

Electrochemical Studies of Pirarubicin and Its Interaction with DNA at a Co/GC Ion Implantation Modified Electrode

MA Xiao-mei, HU Jing-bo, LI Qi-long

2004, 20(6):  751-756. 

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The electrochemical behavior of pirarubicin(THP) and its interaction with DNA at a Co/GC modified electrode was studied by linear sweep and cyclic voltammetries. In a 0.01 mol/L B-R buffer solution(pH=7.0), the reaction of DNA with THP formed an electrochemical nonactive complex, resulting in a decrease in the THP equilibrium concentration and its reduction current. The composition of the complex was THP:DNA=2:1. The combining constant is 2.73×10¹⁰. The electrode reaction rate constant k_s and the electron transfer coefficient α are 1.32 s^-1 and 0.56, respectively. The decrease in the peak current was proportional to the DNA concentration and was used to determine the DNA concentration. The experiment of XPS showed that Co was surely implanted into the surface of GCE(glassy carbon electrode) and the implanted Co at GCE can improve the electrocatalytic activity.

Adsorption of Thiourea and Formation of Nickel-thiourea Complexes at Initial Stage of Nickel Deposition

LIU Xin-yu, HU Guang-hui, WU Hui-huang, YANG Fang-zu

2004, 20(6):  757-760. 

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The effect of thiourea(TU) on the nickel deposition process was analyzed by means of linear-sweep voltammetry. Raman spectroscopy and infrared reflectance spectroscopy were used to investigate the adsorption of TU and the formation of nickel-TU complexes on copper surface. The experimental results indicate that the nucleation and the preceding conversion step are involved in the deposition of nickel on copper electrodes. TU makes the onset nucleation potential negative due to the formation of nickel-TU complexes, which can accelerate the nickel deposition. Moreover, the S atom in the TU molecule adsorbed on copper surface facilitates the coordination of TU to Ni²⁺. Meanwhile, TU might be adsorbed at a flatter orientation if no Ni²⁺ is on the surface, while at a perpendicular orientation when Ni²⁺ is coadsorbed.

Characterization of Ni/AlMCM-41 Catalysts and Their Catalytic Performance in n-Dodecane Hydroconversion

FANG Ke-gong, WEI Wei, REN Jie, SUN Yu-han

2004, 20(6):  761-765. 

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A series of Ni/AlMCM-41 catalysts with different nickel contents was prepared via the incipient wetness impregnation method. The effects of the nickel content on the structure, acidity and metal function of the catalysts were studied by using different techniques. In the test of n-dodecane hydroconversion, it was found that the metal and acid functions were well balanced over a 2.0%Ni(mass fraction)/AlMCM-41 catalyst, which gave the maximal isomerization selectivity and a homolytic cleavage products.

Thermochemical Study of Coordination of Holmium Chloride Hydrate with Diethylammonium Diethyldithiocarbamate

ZHAO Feng-qi, CHEN San-ping, JIAO Bao-juan, REN Yi-xia, GAO Sheng-li, SHI Qi-zhen

2004, 20(6):  766-770. 

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The complex of holmium chloride hydrate with diethylammonium diethyldithiocarbamate(D-DDC) was synthesized via mixing their solutions in absolute alcohol under a dry N₂ atmosphere. The elemental and chemical analyses show that the complex has the general formula Et₂NH₂[Ho(S₂CNEt₂)₄]. It was also characterized by IR spectroscopy. The enthalpies of the dissolution of holmium chloride hydrate and D-DDC in absolute alcohol at 298.15 K, and the enthalpy changes of liquid-phase reactions of the formation of Et₂NH₂[Ho(S₂CNEt₂)₄] at different temperatures were determined by microcalorimetry. On the basis of experimental and calculated results, three thermodynamic parameters(the activation enthalpy, the activation entropy and the activation free energy), the rate constant and three kinetic parameters(the apparent activation energy, the pre-exponential constant and the reaction order) of the liquid-phase reaction of the complex formation were obtained. The enthalpy change of the solid-phase complex formation reaction at 298.15 K was calculated by means of a thermochemical cycle.

Transition Between Solid-like and Liquid-like States in Soft Silica Suspensions

AN Kang, HU Ji-fan, SUN De-jun, QIN Hong-wei, ZHANG Jie, HAN Tao, ZHANG Ling

2004, 20(6):  771-773. 

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The influences of silica volume fraction, electrolyte concentration and pH value upon the stress dependence of elastic modulus G′and viscous modulus G″ were investigated. The results show that the suspension transforms from a liquid-like state to a solid-like state with increasing the volume fraction of silica. Such a solid-like state can be transformed back into a liquid-like state under the application of a larger stress. At the higher volume fraction, the larger critical stress is required to induce the transition from solid-like to liquid-like state. As the electrolyte concentration decreases or pH value increases, the inter-particle force increases, which causes the state transition to occur at a higher stress.

Relationship between Structures and Carcinogenicities of Heterocyclic Amines

JU Xue-hai, DAI Qian-huan, CHEN Sha, WANG Wen-jun

2004, 20(6):  774-777. 

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Semi-empirical molecular orbital calculations were performed on heterocyclic aromatic amines(HCAs). The relationship between the structures and the carcinogenicities can be rationally elucidated by the models based on the metabolism of HCAs and the Di-region theory. The degree of easiness for the formation of Di-region electrophilic centers determines the carcinogenic activity. There is a good linear relationship between the observed carcinogenicities and the PM3 calculated parameters, with r=0.973 and F=29.8>(F^*_0.^*₀₁).

Molecular Chirality and Chiral Superlattice in Crystal of Tetrakis[(pyrrol-1-yl)methyl]methane

XU Wei, LU Yin-xiang, LIU Chun-ming, LAN Bi-jian, ZHOU Hui, WANG Jing-mei

2004, 20(6):  778-780. 

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The crystal structure of tetrakis[(pyrrol-1-yl)methyl]methane was determined by X-ray diffraction measurement, and the result shows that it belongs to monoclinic crystal system, space group is P2₁/n, with a=0.9284(3) nm, b=1.0950(6) nm, c=1.8749(8) nm; α=γ= 90.00(4)°, β=103.63(3)°, V=1.8523(14) nm³, Z=4, ρ_calcd.=1.192 kg/m³, μ=0.072 nm^-1, F(000)=712, R₁=0.0854, wR₂=0.1884. It has been found that the molecules exist in two enantiomeric states. Enantioselective self-assemblies such as one-dimensional molecular stacks in a single handedness, homochiral monolayers and a chiral superlattice are specified in this racemic crystal. In addition, a simple technique is advocated to distinguish chiral states from tetrahedral molecules in the solid state. The present R/S nomenclature of the tetracooradinated carbon centers is used solely for its convenience to distinguish the two enantiomeric states, but not used to determine the absolute configurations.

Studies on Upconversion Mechanism of ZrO₂:Er³⁺,Yb³⁺ Nanocrystals Under Excitation at 488 and 980 nm

JIA Ruo-kun, JIAN Wen-ping, GUO Wei, SHAN Gui-ye, LÜ Qian, LIU Zhao-yue, BAI Yu-bai, LI Tie-jin, KONG Xiang-gu

2004, 20(6):  781-784. 

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Erbium, Ytterbium-codoped ZrO₂ nanoparticles(ZrO₂:Er³⁺,Yb³⁺) were prepared by the sol-emulsion-gel technique. The purpose of the present study is the application of upconversion phosphor in the biological label. In order to make out the mechanism of upconversion under 980 nm excitation the 488 nm pump was used. The influence of temperature on the crystallite phase was studied. The results confirm the upconverted mechanism in ZrO₂:Er³⁺,Yb³⁺ nanocrystals is due to an energy transfer upconversion(ETU).

Inhibition of Triton X-100/n-C₅H₁₁OH/H₂O System on Hydrolysis of Cephanone

QIAN Jun-hong, GUO Rong, ZHU Jun

2004, 20(6):  785-789. 

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The hydrolysis of cephanone in Triton X-100 micelle and Triton X-100/n-C₅H₁₁OH/H₂O(O/W) microemulsion were studied by means of UV-Vis absorption spectroscopy. The results show that compared with water, Triton X-100 micelle and Triton X-100/n-C₅H₁₁OH/H₂O(O/W) microemulsion can inhibit the hydrolysis of cephanone. The inhibition effects of Triton X-100 micelle and Triton X-100/n-C₅H₁₁OH/H₂O(O/W) microemulsion on the hydrolysis of cephanone are related to the location of cephanone in the interphases of Triton X-100 micelles and Triton X-100/n-C₅H₁₁OH/H₂O(O/W) microemulsion droplets.

Electroluminescence from Exciplex on the Interface Between TPD and La(PMIP)₃(Bipy)

GAO De-qing, BIAN Zu-qiang, HUANG Yan-yi, HUANG Chun-hui, IBRAHIM K., LIU Feng-qin

2004, 20(6):  790-794. 

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The bilayer organic light-emitting diode(OLED) with a blue fluorescent lanthanum complex, tris(1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone)-(2,2′-dipyridyl) lanthanum [La(PMIP)₃(Bipy)], as a light emitting material and N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine(TPD) as a hole transporting material emits bright green light instead of blue light. The data of the absorption, the photoluminescence(PL) and the photoluminescence excitation(PLE) spectra of TPD, La(PMIP)₃(Bipy) and the mixture of TPD and La(PMIP)₃(Bipy)(molar ratio 1:1) prove that the electroluminescent emission originates from the exciplex on the interface between TPD and La(PMIP)₃(Bipy). By improving device configuration with tris(8-hydroxyquinoline) aluminum(ALQ) as an electron transporting material, a maximum luminance of 800 cd/m² was obtained.

Interaction of Rheumatoid Factor with Immobilized ss-DNA

WANG Lian-yong, LU Jing, YU Yao-ting

2004, 20(6):  795-800. 

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Rheumatoid factors(RFs) are the characteristic autoantibodies of rheumatoid arthritis. Recent researches in our laboratory showed that the immobilized single-stranded DNA(ss-DNA) immunoadsorbent can selectively remove RFs from the serum of patients. In the present paper are studied the modification of argininine, tryptophan, lysine residues and carboxyl terminus of IgGRF, which was separated from patients′ serum, with 1,2-cyclohexanedione(CHD), N-bromosuccinimide(NBS), pyridoxal 5′-phosphate(PP) and 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide(EDC) respectively, and their effects on the adsorption capacity of the immobilized ss-DNA immunoadsorbent for IgGRF. After the specific modification, the corresponding adsorption capacities of the adsorbents were changed from 48%, 46%, 44% and 54% to 84%, 14%, 21% and 81%, respectively. These results indicate that the electrostatic or ionic-bonding is essential for the interaction between ss-DNA and IgGRF.

Syntheses and Structures of Blue Luminescent Zinc(Ⅱ) Complexes with 2,6-Bis(imino)pyridyl Ligands

FAN Rui-qing, ZHU Dong-sheng, MU Ying, SU Qing

2004, 20(6):  801-803. 

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A New Steroidal Alkaloid from Bulbs of Fritillaria Hupehensis Hsiao et K. C. Hsia

ZHANG Yong-hui, RUAN Han-li, FANG Pi-hui, CAI Jin-yan, WU Ji-zhou

2004, 20(6):  804-806. 

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Syntheses and Properties of Lanthanide Hydroxy-meso-tetra(p-chlorophenyl)porphyrin Complexes

YU Miao, YU Lian-xiang, JIAN Wen-ping, YANG Wen-sheng, LIU Guo-fa

2004, 20(6):  807-809. 

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Preparation and Electrochemical Properties of 3-Phenyl-6-aryl-1,2,4-triazolo[3,4-b][1,3,4]-thiadiazoles

CHEN Miao, XIAO Tai, LI Hui-xue, LIU Xiang

2004, 20(6):  810-812. 

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A Convenient and Easy-controlled Method for Preparation of 7,10-Bis(2,2,2-trichloroethyloxycarbonyl)-10-deacetyl Baccatin Ⅲ

QI Xin, XU Li, LIN Xiao-ju, JI Yong, WANG Tian-wei

2004, 20(6):  813-816. 

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Surface-enhanced Raman Scattering from Molecules Adsorbed on Mixed Silver/Gold Nanoparticle Surfaces

FANG Jing-huai, HUANG Yun-xia, LI Xia, DOU Xiao-ming

2004, 20(6):  817-820. 

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Kinetics and Mechanism of Exothermic First-stage Decomposition Reaction for 2,6-Dinitro-4,8-bis(2,2,2-trinitroethyl)-2,4,6,8-tetra-azabicyclo[3.3.1] nonane-3,7-dionel

HU Rong-zu, YANG De-suo, ZHAO Feng-qi, CHEN Pei, LUO Yang, CHEN San-ping, ZHAO Hong-an, SONG Ji-rong, GAO Sheng-li, SHI Qi-zhen

2004, 20(6):  821-825. 

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Microcontact Printing Techniques in Bioscience

FENG Xi-zen, HOU Sun, CHAN Qi-lin, WANG Li-kai, QIN Ming, HAN Pei-dong

2004, 20(6):  826-832. 

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The microcontact printing(μCP) technology available for patterning protein, DNA hybridization, immunoassay and cellular cocultures onto solid surface are reviewed. This review describes some of the techniques currently employed for creating two-dimensional biomolecular microarray, and the research results regarding their effectiveness. In addition, the applications of the impact of μCP technology in the field of biosciences are also presented.