中国化学快报

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A Facile One-pot Method for the Synthesis of Vinyl Ethers from 2-Hydroxyalkyl Phenyl Selenides

Shou Ri SHENG, Hai Rong LUO, Wu Kang SUN, Xian HUANG

中国化学快报. 2005, 16(11): 1421-1423.

摘要 ( )

可视化

A mild, one-pot procedure for the synthesis of vinyl ethers in good yields from 2-hydroxyalkyl phenyl selenides with primary or secondary organic halides has been developed.

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A New and Efficient Synthesis of 2H-3,1-Benzoxazine Compounds

Jia Rong LI, Shu Ling MA

中国化学快报. 2005, 16(11): 1424-1426.

摘要 ( )

可视化

2H-3, 1-Benzoxazine derivatives were synthesized by cyclocondensation of 5-nitro-2-cyanoaniline with relative ketone or aldehyde with ZnCl₂ as a catalyst. This is a new efficient synthetic route of 2H-3, 1-benzoxazine cyclic compounds.

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Asymmetric Baylis-Hillman Reaction between Chiral Activated Alkenes and Aromatic Aldehydes in Me₃ N/H₂ O/Solvent Medium

Ke HE, Zheng Hong ZHOU, Hong Ying TANG, Guo Feng ZHAO, Chu Chi TANG

中国化学快报. 2005, 16(11): 1427-1430.

摘要 ( )

可视化

Chiral activated alkene, L-menthyl acrylate and (+)-N-α-phenylethyl acrylamide,induced asymmetric Baylis-Hillman reaction of aromatic aldehydes was realized at 25℃ for 7 days in Me₃ N/H₂ O/solvent homogeneous medium. The corresponding Baylis-Hillman adducts were obtained in good chemical yield with moderate to excellent diastereoselectivity (up to 99% de).

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Synthesis of a Novel α-Methylene-β-carboxy-γ-thiobutyrolactones

Xiao Kui WANG, Jian Lei KANG, Song LI

中国化学快报. 2005, 16(11): 1431-1433.

摘要 ( )

可视化

A new series compounds, α-methylene-β-carboxy-γ-thiobutyrolactones, have been prepared and their biological evaluation in vitro and in vivo have been described. The structures of these compounds were confirmed by ¹H NMR and FAB-MS spectra.

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Design,Synthesis and Investigation of Bone Affinity of the Conjugates of 5-Fluorouracil and Hydroxybisphosphonate

Liu Hua XU, Hu ZHENG, Ling Ling WENG

中国化学快报. 2005, 16(11): 1434-1436.

摘要 ( )

可视化

A series of novel bone-targeting antitumor agents-the conjugates of 5-fluorouracil and hydroxybisphosphonate were designed and synthesized, their structures were confirmed by ¹H-NMR, ¹³C-NMR, ³¹P-NMR, MS, and element analysis. The tests of bone-targeting activity show that these compounds have an obvious affinity for bone.

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Convenient and Highly Efficient Inversion of 1β-OH Configuration of trans-Vitamin D₃

Yong Bin HAN, Jin Ping CHEN, Ying Ying LI, Bai Ning LIU, Guo Qiang YANG, Yi LI

中国化学快报. 2005, 16(11): 1437-1440.

摘要 ( )

可视化

A convenient and highly efficient conversion of 1β-OH-trans-vitamin D₃, a main byproduct in synthesis of active vitamin D₃, to 1α-OH-trans-vitamin D₃ is reported. The conversion could be accomplished in 1 minute with 90% yield.

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Synthesis and Bioactivity of Isosteviol Derivatives:A Facile Method for Preparation of Ent-16α-hydroxy-15β-hydroxymethylbeyeran-19-oic Acid

Jing Chao TAO, Guo Qiang TIAN, Yan Bing ZHANG, Yu Qin FU, Gui Fu DAI, Ya WU

中国化学快报. 2005, 16(11): 1441-1444.

摘要 ( )

可视化

In this paper, two new compounds, ent-16α-hydroxy-15β-hydroxymethylbeyeran-19-oic acid 4 and its ethyl ester 5 were synthesized in good yield with a facile method that has never been reported. The mechanism of this reaction was discussed and the mono-hydroxymethylation of carbonyl compound with two a-hydrogens via Tollens' reaction was firstly achieved. Compounds 2-5 were tested for activity of inhibition against glycosidases, among which 5 displays good inhibition of β-glucosidase and α-mannase, respectively.

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Studies on the Synthesis of Morphinan Alkaloid:Preparation of the Key Allylic Silyl Ether Precursor

Zhen Lei SONG, Yong Qiang TU, Shuan Hu GAO, Yi Jun JIANG, Shu Yu ZHANG

中国化学快报. 2005, 16(11): 1446-1447.

摘要 ( )

可视化

A convergent strategy to the key allylic silyl ether precursor 4 in our synthetic efforts toward morphinan alkaloid is presented. The vital step is the selective 1,2-addition of the organocerium agent of 6 to ketene 5.

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Total Synthesis of (-)-Tetrahydrolipstatin by the Tandem Mukaiyama-aldol Lactonization

Jian YIN, Xiao Bo YANG, Zai Xin CHEN, Yi Hua ZHANG

中国化学快报. 2005, 16(11): 1448-1450.

摘要 ( )

可视化

(-)-Tetrahydrolipstatin 1 was synthesized in three steps and 33.8% overall yield from aldehyde 6 by tandem Mukaiyama-aldol lactonization, which offered a concise, efficient and highly diastereoselective route to this antiobesity drug. We also presented a resolution method for preparation of the crucial intermediate,β-(t-butyldimethylsilyloxy)tetradecanal.

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Synthesis of 2,2'-(Substituted Arylmethylene) bis (1,6,6-trimethyl-6,7,8,9-tetrahydrophenanthro[1,2-b]furan-10,11-dione) Derivatives

Jiang Ke QIN, Xian Zhang BU, Yu Fang WANG, Zhi Yun DU, Xing Yuan WANG, Zhi Shu HUANG, Lin MA, Lin Kun AN, Lian Quan GU

中国化学快报. 2005, 16(11): 1451-1454.

摘要 ( )

可视化

The reactions of tanshinone ⅡA with aromatic aldehydes have been investigated and several 2, 2'-(substituted arylmethylene) bis (1,6,6-trimethyl-6,7,8,9-tetrahydrophenanthro[1,2-b]-furan-10, 11-dione) derivatives were obtained.

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Photopromoted Carbonylation of Alkyl Bromides Catalyzed by Copper Salts under Ambient Conditions

Tao WEN, Ying Ping JIA, Da Bin GAO, Jing Mei YIN, Guang Yun ZHOU, Jing LIU, Xiang Sheng WANG

中国化学快报. 2005, 16(11): 1455-1458.

摘要 ( )

可视化

Photopromoted carbonylation of alkyl bromides with carbon monoxide or carbon dioxide catalyzed by copper salts can be carried out under ambient conditions (atmospheric pressure and room temperature) and the corresponding ester was produced. The yield and the selectivity of the ester can be improved greatly by addition of sodium phosphate.

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Pinacol Coupling Reactions Catalyzed by Active Zinc

Hui ZHAO, Wei DENG, Qing Xiang GUO

中国化学快报. 2005, 16(11): 1459-1462.

摘要 ( )

可视化

Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition, the results indicated that the zinc activity has a direct relation to the coupling reactivity compared to untreated zinc or other general active zinc.

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Facile Synthesis of Ophipogonin C'and its Three Analogues

Shu Jie HOU, Chuan Chun ZOU, Liang ZHOU, Ping Sheng LEI, De Quan YU

中国化学快报. 2005, 16(11): 1463-1466.

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可视化

Three natural diosgenyl glycosides:Ophipogonin C' (A), Polyphillin C (B), diosgenyl α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside (DRG) (C) and one of their analogue diosgenyl α-L-rhannopyranosyl-(1→6)-β-D-glucopyranoside (D) were first systemic synthesized in a facile way in high yields.

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Aerobic Enantioselective Epoxidation of Styrene Analogues Induced by (β-Diketone)-iron (Ⅲ) Complex

Qing Fang CHENG, Xing You XU, Wei Xing MA, Shu Jie YANG, Tian Pa YOU

中国化学快报. 2005, 16(11): 1467-1470.

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可视化

Tris(d,d-dicampholylmethanato) iron (Ⅲ) complex, Fe(dcm)₃, was found to be an excellent catalyst for asymmetric oxygenation of styrene analogues into the corresponding epoxides. Good chemical yields and higher enantioselectivity were obtained with combined use of molecular oxygen and an aldehyde at 30℃. Some factors influencing enantioselectivity were discussed.

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Enantioseparation of Racemic Anti-hepatitis New Drug Bicyclol with Crystallization

Wei HU, Yan LI, Chun Zhen ZHANG

中国化学快报. 2005, 16(11): 1471-1473.

摘要 ( )

可视化

The enantioseparation of anti-hepatitis new drug (±)-bicyclol was performed by optically active alkaloid. The alcoholic acid, the hydrolysate of bicyclol was reacted with optically active alkaloid, such as brucine, strychnine, quinidine etc., the diastereoisomeric salts were obtained by fractional recrystallization, then separately decomposed and esterified to obtain the two enantiomers of bicyclol. The pharmacological study showed that the effect of (-)-bicyclol was more potent than racemic bicyclol two times and the potency of (+)-bicyclol was incative.

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A New Diels-Alder Type Adduct and a New Flavone from the Stem and Root Bark of Morus mongolica

Jie KANG, Ruo Yun CHEN, De Quan YU

中国化学快报. 2005, 16(11): 1474-1476.

摘要 ( )

可视化

A new Diels-Alder type adduct mongolicin G (1) and a new flavone 5'-(1", 1"-dimethylallyl)-5,7,2',4'-tetrahydroxyflavone (2) were isolated from the stem and root bark of Morus mongolica. Their structures were determined by spectroscopic analysis and chiroptical methods.

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A Novel Dimeric Eremophilane from Ligularia virgaurea spp.oligocephala

Quan Xiang WU, Xia LIU, Yan Ping SHI

中国化学快报. 2005, 16(11): 1477-1480.

摘要 ( )

可视化

A novel dimeric eremophilane, ligulolide B, was isolated from the alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala. The structure was elucidated by various spectroscopic methods including intensive 2D NMR techniques (¹H-¹H COSY, gHMQC,gHMBC and ¹H-¹H NOESY) and HR-ESI-MS.

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A New Alkaloid from Sinomenium acutum

Wei Ming CHENG, Feng QIU, Li Jun WU, Xin Sheng YAO

中国化学快报. 2005, 16(11): 1481-1483.

摘要 ( )

可视化

Sinomenium acutum is widely used in East and South Asia for the treatment of many diseases, especially rheumatoid arthritis (RA). The chemical research on Sinomenium acutum led to the isolation of a new alkaloid compound (1). On the basis of chemical evidences and spectral analysis, 1 was identified as N-(1, 7-dimethoxylphenanthren-2-yl)acetamide.

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A New β-Carboline Alkaloid and a New Derivate of Isoferulic Acid from Anemone altaica

Zhong Jie ZOU, Yue Sheng DONG, Jun Shan YANG

中国化学快报. 2005, 16(11): 1484-1486.

摘要 ( )

可视化

A new β-carboline alkaloid, 4-(9H-β-carbolin-1-yl)-4-oxobutyric acid and a new derivate of isoferulic acid, (E)-3-(3-hydroxy-4-methoxyphenyl)acrylic acid carboxymethyl ester,were isolated from the roots of Anemone altaica. Their structures were determined on the basis of spectral data.

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A New Sesquiterpene from Transformation of Curdione by Cell Suspension Culture of Platycodon Grandiflorum

Xiao Chi MA, Li Jun WU, De An GUO

中国化学快报. 2005, 16(11): 1487-1488.

摘要 ( )

可视化

A new sesquiterpene was isolated from transformation of curdione by cell suspension culture of Platycodon grandiflorum. The structure of the new compound was elucidated on the basis of spectral methods including 2D NMR.

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A Novel Hydroperoxyl Substituted Cembranolide Diterpene from Marine Soft Coral Lobophytum crassum

Shuai Wen YIN, Yan Ping SHI, Xiao Ming LI, Bin Gui WANG

中国化学快报. 2005, 16(11): 1489-1491.

摘要 ( )

可视化

A new cembranolide diterpene with a hydroperoxyl substitution was isolated from the marine soft coral Lobophytum crassum. The structure was elucidated on the basis of chemical and spectral methods.

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Tryptophan Modification and Fluorescence Spectrum of Hyaluronidase

Li Rong TENG, Yu Zhuo CHU, Xiao Ping ZHANG, Xiao Kun YU, Jing WANG, Song HAN, Bo Xun ZHANG, Hao FAN, Lan Ying LIU

中国化学快报. 2005, 16(11): 1492-1494.

摘要 ( )

可视化

Tryptophan residues in hyaluronidase (HAase) were modified by N-bromosuccinimide (NBS), the results indicated that there were eleven tryptophan residues in HAase, one of which was exposed and essential for the activity of the enzyme. The study on fluorescence quenching showed that KI could not quench all of the fluorescence from Trp residues in HAase, while acrylamide (Act) could quench almost all of the fluorescence from Trp residues in HAase. The collisional quenching constants (K_D) of HAase at different concentrations of Act were calculated in terms of Stcm-Volmer equation. The results implied that some of the Trp residues were buried in the interior of HAase and the Trp residue on the surface of HAase was not located in the hydrophobic pocket.

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New Sorbent for Bilirubin Removal from Human Plasma:Albumin Immobilized Microporous Membranous PTFE Capillaries

Lei ZHANG, Gu JIN

中国化学快报. 2005, 16(11): 1494-1498.

摘要 ( )

可视化

In this study, we developed a tailored capillary sorbent for bilirubin removal. For immobilized bioligand, capillaries were grafted with epoxy groups using RIGP. The HSA immobilized capillaries has a high affinity adsorption capacity (71.2 mg bilirubin/g polymer) and a shorter adsorption equilibrium time (about 60 min).

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Simultaneous Determination of Heroin,Amphetamine and their Basic Impurities and Adulterants Using Microemulsion Electrokinetic Chromatography

Tao WEN, Xia ZHAO, Guo An LUO, Jian WANG, Yi Ming WANG, Pan LI, Jun ZHU, Zhong Shang YU

中国化学快报. 2005, 16(11): 1499-1502.

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可视化

Simultaneous separation of 17 species of heroin, amphetamine and their basic impurities and adulterants was conducted within 10 minutes by using capillary microemulsion electrokinetic chromatography. The influences of pH and 1-butanol cosurfactant on the separation were investigated, and 1-butanol was found to be a principal factor to improve separation efficiency.

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A New Molecularly Imprinted Polymer for Solid-phase Extraction of Cotinine from Human Urine

Jun YANG, Xiao Lan ZHU, Ji Bao CAI, Qing De SU, Yun GAO, Liang ZHANG

中国化学快报. 2005, 16(11): 1503-1506.

摘要 ( )

可视化

A molecularly imprinted polymer (MIP), prepared around a cotinine template, has been synthesized. The feasibility of using the polymer for solid-phase extraction (SPE) of cotinine from biological samples has been investigated. The results show that cotinine can be quantitatively retained and eluted from the polymer. Experiments with human urine samples indicate that clean target analyte is obtained for HPLC with UV detection using the protocol.

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NMR Studies on the Subacute Biochemical Effects of Aristolochic Acid on Rat Serum

XiaoYu ZHANG, Hui Feng WU, Xiao Jing LI, Feng Kui PEI, Jia Zuan NI

中国化学快报. 2005, 16(11): 1507-1510.

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可视化

The subacute effect of aristolochic acid (AA) on rat serum was studied by NMR method.The biochemical effects induced by AA were characterized by an increase in the amounts of creatinine, trimethylamine N-oxide, acetoacetate, acetate and 3-D-hydroxybutyrate and lactate in serum from ¹H NMR spectra. Principal component analysis was used for further comparing the similarities of ¹H NMR spectral profiles of serum from rats treated with AA and model toxins.

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Capillary Electrophoretic Determination of Jinggangmycin A in Formulations Using Direct UV Detection

Jin HE, Xin LIU, Yi Shi LIU, Zi Niu YU

中国化学快报. 2005, 16(11): 1511-1514.

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可视化

A simple, fast and reliable method was developed for the analysis ofjinggangmycin A (validamycin A) in commercial formulations. The running buffer used was acetate buffer (100mmol/L, pH 4.7) with 15 kV as the applied voltage. The detection was achieved by using direct UV mode at 200 nm and the detection limit was 0.2 μg/mL. Linearity in the concentration range of 5-500 μg/mL was excellent (R²>0.999). The run-to-run repeatability (n=3), as expressed by the relative standard deviation (RSD) for migration times and peak areas were less than 0.5% and 3.0% respectively. The mean recovery ranged from 97.2% to 101.4%.

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Spectrophotometric and Voltammetric Studies on the Interaction of Heparin with Phenosafranine

Wei SUN, Ya Qin DING, Kui JIAO

中国化学快报. 2005, 16(11): 1515-1518.

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可视化

The interaction of phenosafranine (PSF) with a glycosaminoglycans of heparin (Hep) in aqueous solution has been characterized by UV-Vis absorption spectrophotometry and cyclic voltammetry in pH 1.5 Britton-Robinson (B-R) buffer solution. The addition of Hep caused decrease of the absorbance of PSF at 532 nm and the redox peak current of PSF. The study showed that an supramolecular complex of PSF-Hep was formed because of the electrostatic attraction of negatively charged Hep with the positively charged PSF, which resulted in the decrease of the equilibrium concentration of PSF in solutions, and the decrease of the absorbance or the Peak current of PSF. The stoichiometry of the Hep/PSF complex was further calculated by voltammetric data with the result of 1:1 complex.

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Solid State NMR and Fluorescence Studies of Conjugated Polymer Nanocomposties

Chao Jun JING, Liu Sheng CHEN, Yi SHI, Xi Gao JIN

中国化学快报. 2005, 16(11): 1519-1522.

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可视化

¹³C spin-lattice relaxation times (T₁) of a conjugated polymer MEH-PPV in polymer/layered silicate nanocomposites together with the steady state fluorescence emission and transient fluorescence decay measurements have been investigated. The T₁ values of the conjugated carbons decrease dramatically according to the reduction of polymer concentration in the nano composites, while the fluorescence life times (τ) show a linear prolonging tendency. The results are explained from the point of view of molecular dynamics.

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Controlled Synthesis of Dendritic Polyaniline Fibers with Diameters from Nanosize to Submicrometersize

Xiao Cong WANG, Shu Jiang DING, Jing CAO, Fa Lun WU, Chen ZHOU, Zhen Zhong YANG

中国化学快报. 2005, 16(11): 1523-1526.

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可视化

Dendritic polyaniline nanofibers and submicrometer-sized fibers have been synthesized by chemical oxidative polymerization of aniline (An) doped with salicylic acid (SA). The diameters of the fibers could be controlled easily from 30 to 400 nm by varying the concentration of aniline and salicylic acid at room temperature. Scanning electron microscopy (SEM) and typical transmission electron microscopy (TEM) were applied to investigate their morphologies. Fourier transform infrared (FTIR) spectrum indicated that the state of the dendritic polyaniline fibers is emerialdine rather than solely the leucoemeraldine or permigraniline forms. The dendritic polyaniline fibers have potential applications as chemical sensors or actuators and neuron devices.

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Dynamic Mechanical Behavior of a Novel Polymeric Composite Damping Material

Cheng ZHANG, Jiang Feng SHENG, Chun An MA

中国化学快报. 2005, 16(11): 1527-1530.

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可视化

The dynamic mechanical behavior of a novel polymeric composite damping material has been investigated in this article. The composite consists of chlorinated polyethylene (CPE),N,N-dicyclohexyl-2-benzothiazolylsufenamide (DZ), 4,4'-thio-bis(3-methyl-6-tert-buthylphenol)(BPSR) and vapor-grown carbon fiber (VGCF). It is found that either the position or the intensity of damping peak can be controlled by changing the composition of CPE/DZ/BPSR composite. Within a certain composition region, damping peak maximum depends on CPE/DZ ratio, whereas damping peak position is controlled by BPSR content. Moreover, the improvement of storage modulus can be achieved by incorporation of VGCF. These results may imply that a damping material possessing both good damping properties and high strength can be designed and obtained.

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Preparation of Multiwall Carbon Nanotubes-supported High Loading Platinum for Vehicular PEMFC Application

Bing ZHANG, Li Juan CHEN, Kai Yong GE, Yan Chuan GUO, Bi Xian PENG

中国化学快报. 2005, 16(11): 1531-1534.

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可视化

Multiwall carbon nanotube-supported Pt (Pt/MWNTs) catalysts with high dispersion and high loading of Pt were prepared by chemical reduction method and the loading of Pt got to 40 wt%. The average diameter of Pt nanoparticles on MWNTs was about 3.5 nm. When the hydrogen and air were used as reactant gases for PEMFC, Pt/MWNTs catalysts showed significantly higher performance than the Pt/XC-72 (carbon black) catalysts.

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Enhancement of Activity of SnO₂ -doped In₂ O₃ /Al₂ O₃ Catalyst for NO Reduction with Propene in the Presence of H₂ O and SO₂

Xiang Yu CUI, Jun Hua LI, Ji Ming HAO, Li Xin FU

中国化学快报. 2005, 16(11): 1535-1538.

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可视化

The novel bimetallic Sn-In/Al₂ O₃ catalysts prepared by three methods for NO reduction by propene were investigated. The results showed that the catalytic activity was enhanced significantly in the presence of H₂ O on sol-gel catalyst, and the maximum NO conversion increased from 46% to 92%, even in the presence of 100 ppm SO₂, NO conversion was still 80%.

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Preparation of Nano-crystalline Tungsten Carbide Thin Film by Magnetron Sputtering and Their Electrocatalytic Property for PNP Reduction

Hua Jun ZHENG, Jian Guo HUANG, Chun An MA

中国化学快报. 2005, 16(11): 1539-1542.

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可视化

Nano-crystalline tungsten carbide thin films were deposited on Ni substrates by magnetron sputtering using WC as target material. The crystal structure and morphology of the thin films were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).Electrochemical investigations showed that the electrode of the thin film exhibited higher electrocatalytic activity in the reaction of p-nitrophenol (PNP) reduction. FT-IR analysis indicated that p-aminophenol (PAP) was synthesized after two step reduction of PNP on nano-crystalline tungsten carbide thin film electrode.

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Interfacial Behaviors of Azocalixarene Derivatives at the Air/Water Interface and Photochromism in the Langmuir-Blodgett Films

Xun GUO, Li ZHANG, Guo Yuan LU, Mei Fang YIN, Fang LIU, Ming Hua LIU

中国化学快报. 2005, 16(11): 1543-1546.

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可视化

The interfacial behaviors of the non-typical amphiphilic compound p-methylphenylazocalix[4]arene 1 and p-chlorophenylazocalix[4]arene 2 at the air/water interface and photochromism in the Langmuir-Blodgett films were studied by surface pressure-area isotherm and UV-Vis spectra. The results indicate that they can form stable monolayers at the air/water interface although they have no hydrophobic alkyl chains, and their LB film underwent reversible trans-cis photoisomerization on UV and daylight illumination.

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Oscillating Frequency Response of a Langasite Crystal Microbalance in Liquid Phase

Qi KANG, Huai Jin ZHANG, Xue Yong LIU, Da Zhong SHEN

中国化学快报. 2005, 16(11): 1547-1550.

摘要 ( )

可视化

The frequency responses of a langasite crystal microbalance (LCM) in liquid phase were investigated. It was shown that the LCM possessed much stronger oscillating ability in liquid phase than that of the commonly used quartz crystal microbalance (QCM). The frequency shifts of the LCM to the changes in mass loading, as well as viscosity and density of the liquid were measured. The LCM was applied to monitor the adsorption process of an ionic liquid film to ethanol vapor.

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A Hybrid Ant Colony Optimization for the Prediction of Protein Secondary Structure

Chao CHEN, Yuan Xin TIAN, Xiao Yong ZOU, Pei Xiang CAI, Jin Yuan MO

中国化学快报. 2005, 16(11): 1551-1554.

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可视化

Based on the concept of ant colony optimization and the idea of population in genetic algorithm, a novel global optimization algorithm, called the hybrid ant colony optimization (HACO), is proposed in this paper to tackle continuous-space optimization problems. It was compared with other well-known stochastic methods in the optimization of the benchmark functions and was also used to solve the problem of selecting appropriate dilation efficiently by optimizing the wavelet power spectrum of the hydrophobic sequence of protein, which is thc key step on using continuous wavelet transform (CWT) to predict a-helices and connecting peptides.

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Spacial Structure of Cationic Phosphorus Ligand-Ru (Ⅱ) Halide Complexes-by DFT Study

Yi Xin ZHAO, Shu Guang WANG

中国化学快报. 2005, 16(11): 1555-1558.

摘要 ( )

可视化

The full-parameter geometry optimization of cationic (S)-BINAP-Ru (Ⅱ) halide complex was performed by DFT method using B3LYP, PW91 and PBE potentials with several basis sets. PW91 with 3-21G/SDD basis sets is found to be the most suitable method with consideration of both precision and efficiency. The dihedral angles (θ) of the binaphthyl or biphenyl with different phosphorus ligand-Ru (Ⅱ) halide complexes were found changing from 59.9 to 79.3 degree, while the natural bite angle (βn) of those complexes only changes from 87.4to 90.3 degree. It is different from the common view of asymmetric organic chemists' that θ directly influences βn.

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Predicting the Relative Retention Time (RRT) of Polybrominated Diphenyl Ethers (PBDEs)

Shu Shen LIU, Yan LIU, Da Qiang YIN, Lian Sheng WANG

中国化学快报. 2005, 16(11): 1559-1562.

摘要 ( )

可视化

Using the molecular electronegativity distance vector descriptors derived directly from the molecular topological structures, the relative retention time (RRT) of polybrominated diphenyl ethers (PBDEs) were predicted. A four-variable regression model (M₃₀) with the correlation coefficient of 0.9816 and the root mean square errors of 0.061 was developed using a training set including 30 PBDEs. The correlation coefficient of 0.9841 and the root mean square errors of 0.054 between the values of RRT predicted by M₃₀ and the RRT observed for 16 external PBDEs show a good predictive potential of M₃₀. The descriptors included in the M₃₀ represent four interactions between four pairs of atom types, i.e., atom-C=and-C=,-C=and >C=, >C=and >C=,-C=and-Br.

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本期目录

2005年, 第16卷, 第11期　刊出日期：2005-11-20

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本期目录

2005年, 第16卷, 第11期 刊出日期：2005-11-20

2005年, 第16卷, 第11期　刊出日期：2005-11-20