中国化学快报

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Synthesis of Tetrahydropyridinyltriazolothiadiazines as Possible Muscarinic Agonists

Guo Qiang HU, Wen Long HUANG, Hai WANG

中国化学快报. 2005, 16(01): 1-3.

摘要 ( )

可视化

4-Amino-5-(pyridin-3-yl)-4H-1,2,4-triazole-3-thiol 1 were condensed with 2-bromo-1-(substituted phenyl) ethanone to give pyridinyltriazolothiadiazines 2a~c, which were quaternarized with methyl iodide and oxidized with 30% hydrogen peroxide to afford the corresponding methyl pyridinium salts 3a~c and pyridine-l-oxides 4a~c, respectively. The reduction of compounds 3 and 4 with NaBH₄ in methanol produced the target compounds 1-methyl-1, 2, 5, 6-tetrahydropyridin-3-yl)-6-aryl-s-triazolothiadiazines 5a~c and 3-(1-hydroxyl-1, 2, 5, 6-tetrahydropyridin-3-yl)-6-aryls-triazolothiadiazines 6a~c, respectively. The endothelium vascular relaxing activity of the target compounds was screened.

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Ring-closing Metathesis on an Allyl-terminated Carbosilane Dendrimer

Chuan Jian ZHOU, Rui Fang GUAN, Sheng Yu FENG, David J. BERG, Stephen R. STOBART

中国化学快报. 2005, 16(01): 4-6.

摘要 ( )

可视化

Grubbs' catalyst was used to prepare a series of carbosilane dendrimers with silacyclopentene peripheral groups. It was found that ring closing metathesis reaction was influenced strongly by the reaction temperature and the amount of catalyst.

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Synthesis of New Benzoimidazole Derivatives

Lin Kun AN, Xian Zhang BU, Zhi Shu HUANG, Lin MA, Lian Quan GU, Albert S. C. CHAN, Yue Ming LI

中国化学快报. 2005, 16(01): 7-10.

摘要 ( )

可视化

The reactions of cryptotanshinone and tanshinone ⅡA with cadaverine and putrescine were investigated. Six new compounds, four with imidazole functional groups and two with oxazole groups, were obtained. The possible reaction mechanism was proposed.

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Synthesis of 2-En-1-one-ebelactonyl Benzoates of Territrem B Analogues from Jujubogenin

Jin Hao ZHAO, Yan Guang WANG, Hai Bo LI, Feng ZHAO, Lei Xiang YANG, Hua BAI, Shoei Sheng LEE, Yu ZHAO

中国化学快报. 2005, 16(01): 11-14.

摘要 ( )

可视化

Two series of territrem B analogues (10a-10c and 18) have been designed and synthesized from jujubogenin 5a which was prepared from jujubogenin glycosides 5b obtained from the leaves of Zizyphus jujuba. The structures of the new compounds were confirmed by ¹H-,¹³C-NMR and MS data. Compounds 10c and 18 showed weak inhibitory effect on AChE at 10^-4mol/L.

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A Novel Asymmetric Synthesis of (-)-cis-1, 3-Dibenzylhexahydrofuro[3,4-d]imidazole-2,4-dione

Wei Hua HAN, Hao Ran LI

中国化学快报. 2005, 16(01): 15-16.

摘要 ( )

可视化

(-)-cis-1, 3-Dibenzyl-hexahydrofuro[3, 4-d]imidazole-2, 4-dione was prepared by a new synthesis method from meso dicarboxylic acid and dehydroabietylamine by asymmetric reduction in good yield with up to 91.6% e.e. value.

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Asymmetric Synthesis of α-Substituted-γ-butyrolactone Empolying Prolinol Type of Auxiliaries

Jia Cheng NING, Shu MAO, Ye Di GUAN

中国化学快报. 2005, 16(01): 17-19.

摘要 ( )

可视化

Eleven (S)-(-)-bishydrocarbyl-(1-alkanoylpyrrolidin-2-yl)-methanol derivatives of three types were synthesized from L-proline, asymmtrically selective alkylation products were obtained by LDA treatment and alkylation using methyl 2-bromoethyl ether, and three types of chiral α-substituted-γ-butyrolactones were obtained by hydrolyzing the alkylation products, with %e.e.being up to 89 percent.

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Synthesis of 6, 9, 11-Trihydroxy-6a, 12a-dehydrorotenoid

Hong Yan ZHENG, Shao Bai LI

中国化学快报. 2005, 16(01): 20-22.

摘要 ( )

可视化

6, 9, 11-Trihydroxy-6a, 12a-dehydrorotenoid 1 (coccineone B) was synthesized from 2-hydroxybenzaldehyde 2 and phloroglucinol.

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Preparation of L-Butyl Lactate via Transesterification by Using Nafion-H Catalyst

Wei LI, Guo Rong ZHENG, Ping LU

中国化学快报. 2005, 16(01): 23-26.

摘要 ( )

可视化

Optically pure L-butyl lactate was synthesized by normal transesterification using nafion-H catalyst in moderate yield. Various reaction conditions were investigated, including the reaction temperature, reaction time, ratio of the starting material and amount of the nafion catalyst.

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EDTA-type Polymer Based on Diazacrown Ether as the Solubilizer of Barium Sulfate to Water

Bo ZHOU, Jian Zhang LI, Chun Hong HE, Sheng Ying QIN

中国化学快报. 2005, 16(01): 27-30.

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可视化

The EDTA dianhydride reacted with diazacrown ethers to obtain the water-soluble EDTA-diazacrown ether polymers 1~3. The effects of crown ether ring in the polymer chains including its cavity size on the solubilization of barium sulfate to water were investigated by comparison with the crown ring-free analogue 4. The result shows that the polymer 2 is the efficient solubilizer of BaSO₄ and the highest solubilization efficiency of the BaSO₄ to water is up to 72.5%.

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Short Synthesis of C-terminal Modified Peptides by a Series-connection Procedure

Gui Jie TIAN, Chuan Liang QIU, Zhe LIU, De Xin WANG

中国化学快报. 2005, 16(01): 31-34.

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可视化

Three peptide alcohols and four peptidyl N-akyl-amides were prepared by a series-connection procedure consisting of n-1 sequencial assembly on solid support followed by ammonolysis with glycinol, benzylamine or n-butylamine, and successive extractionelution through C-18 layer. All products were obtained from this procedure without further purification,in an overall yield of 75-86%.

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Palladium Catalyzed Synthesis of Fluorine-containing 3-Biaryl-1-ferrocenyl-2-propene-1-one

Qing Bao SONG, Ru Xiang LIN, Tian Hua SHEN

中国化学快报. 2005, 16(01): 35-37.

摘要 ( )

可视化

The novel organometallic compounds, 3-[4'(or 2')-(4"-fluorophenyl)] phenyl-1-ferrocenyl-2-propen-1-ones 5 were synthesized for nonlinear optical chromophores by Pd (0) catalyzed Suzuki cross-coupling reaction. Their structures were established with elemental analysis, MS, IR and ¹H NMR spectroscopies.

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Synthesis and Antitumor Activity of C-2/C-10 Modified Analogues of Docetaxel

Wei Shuo FANG, Hong Yan LIU, Qi Cheng FANG

中国化学快报. 2005, 16(01): 38-40.

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可视化

Four 10-propionyl docetaxel analogues (11a-d) with 2α-amido substituents were prepared, and their antitumor activity against three solid tumor cell lines and their drug-resistant counterparts were determined.

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Synthesis and Characterization of Novel Organic/Inorganic Hybrid Polymers Containing Polyhedral Oligosilsesquioxanes

Hong Yao XU, Xiao Yan GAO, Shan Yi GUANG, Feng Zhi CHANG

中国化学快报. 2005, 16(01): 41-44.

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可视化

Hybrid polymers, poly(vinyl pyrrolidone-co-isobutyl styryl polyhedral oligomeric silsesquioxanes)s (PVP-POSS) were synthesized by one step polymerization and characterized using GPC and DSC. Addition of POSS significantly increases the Tg of polyvinylpyrrolidone at a fair high POSS content and obtained high molecular weight polymers with very narrow molecular distribution. The POSS content in the resulted hybrids can be controlled by varying the POSS feed ratio.

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Lipase-catalyzed Regioselective Synthesis of Vinyl Ester Derivatives of Thiamphenicol:Novel Thiamphenicol Monomers for Preparation of Macromolecular Antibiotic

Yu Zhen SHI, Zhi Chun CHEN, Na WANG, Qi WU, Xian Fu LIN

中国化学快报. 2005, 16(01): 45-48.

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可视化

Three polymerizable vinyl thiamphenicol esters with different acyl donor carbon chain length (C4, C6, C10) were regioselectivly synthesized by Lipozyme^® (immobilized from mucor miehei) in acetone at 50℃ for 12 h to give 73%, 81%, 63% yield, respectively. The products were valuable monomers for preparation of macromolecular antibiotic.

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Two New Sequiterpenoids from Helicteres angustifolia

Xin Dong GUO, Zhi Shu HUANG, Ya Dan BAO, Lin Kun AN, Lin MA, Lian Quan GU

中国化学快报. 2005, 16(01): 49-52.

摘要 ( )

可视化

A new sesquiterpenoid lactone, 3,6,9-trimethyl-pyrano[2,3,4-de]chromen-2-one (1) and a novel sesquiterpenoid quinone, 6-[2-(5-acetyl-2,7-dimethyl-8-oxo-bicyclo[4.2.0]octa-l,3,5-trien-7-yl)-2-oxo-ethyl]-3,9-dimethylnaphtho[1,8-bc]pyran-7,8-dione (2) together with a known perezone (3) were isolated from the roots of Helicteres angustifolia. The structures were elucidated as mainly on the basis of 1D and 2D NMR spectroscopic data.

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Septemloside III:A Nonasaccharide Saponin from the Bark of Kalopanax septemlobus (Thunb.) Koidz

Jian Yuan YIN, Qin MENG, En Si WANG

中国化学快报. 2005, 16(01): 53-56.

摘要 ( )

可视化

A nonasaccharide saponin, new hederagenin saponin, had been isolated from the bark of Kalopanax septemlobus (Thunb.) Koidz., and its structure was elucidated by HRESI-MS, NMR experiments and chemical analyses as 3-O-β-D-xylopyranosyl-(1→4)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl hederagenin 28-O-β-D-xylopyranosyl-(1→3)-β-D-xylopyranosyl-(1→2)-[α-L-rharnnopyranosy 1-(1→4)-β-D-glucopyranosyl-(1→6)]-β-D-glucopyranoside.

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Three New Diarylpropanes from Dioscorea composita

Shun Li YANG, Xi Kui LIU

中国化学快报. 2005, 16(01): 57-60.

摘要 ( )

可视化

Three new diarylpropanes were isolated from the dried rhizomes of Dioscorea composita Hemsl., and their structures were determined as 1, 3-bis-(2-hydroxy-4-methoxyphenyl)propane (1), 1, 3-bis-(2, 4-dihydroxyphenyl)propane (2), 1-(2'-hydroxy-4'-O-β-D-glucopyranosyphenyl)-3-(2", 4"-dihydroxyphenyl)propane (3), by spectroscopic analysis, respectively.

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New Eudesmenes from Erigeron annus

Xin LI, Qiu Hong WU, Kun GAO

中国化学快报. 2005, 16(01): 61-63.

摘要 ( )

可视化

Chemical investigation of Erigeron annus afforded two new eudesmenes, which were identified as 1β, 5α-dihydroxyeudesma-4(15)-en (1) and 1β, 7α-dihydroxyeudesma-4(15)-en (2).Their structures were established by spectroscopic methods including 2D NMR experiments.

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Determination of Dopamine in the Presence of Ascorbic Acid on the IrO₂-Ta₂O₅ Type DSA Electrode

Yang LIU, Zhi Ying LI, Jing Hong LI

中国化学快报. 2005, 16(01): 64-66.

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可视化

IrO₂/Ta₂O₅ (70%:30%, molar ratio) electrodes (ITEs) were prepared by the thermal decomposition method. Typical "mud-cracked" surface and surface enrichment of Ta were observed. The determination of dopamine (DA) was carried out in the presence of ascorbic acid (AA). The detection limit of DA was 5×10^-5mol/L without the interference of AA.

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Determination of Size Distribution of Nano-particles by Capillary Zone Electrophoresis

Yan XUE, Hai Ying YANG, Yong Tan YANG

中国化学快报. 2005, 16(01): 67-70.

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可视化

A new method was developed for the determination of the size distribution of nano-particles by capillary zone electrophoresis (CZE). Scattering effect of nanoparticles was studied. This method for the determination of size distribution was statistical.

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Preliminary Study on Cordycepin-DNA Interaction by Raman Spectroscopy

Jian Ya LING, Qin Zheng YANG, Shan Shan LUO, Yan LI, Chang Kai ZHANG

中国化学快报. 2005, 16(01): 71-74.

摘要 ( )

可视化

The interaction of cordycepin with calf thymus DNA was investigated at physiological pH with drug/DNA molar ratio of 8. The Raman spectroscopy results indicated that the intercalation of high concentration cordycepin and the interaction of cordycepin with PO₂ group led to a major reduction of B-form DNA structure in favor of A-form DNA.

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Platelet Adhesion onto Nitinol Surfaces Modified by Microwave Cold-plasma

Jun YANG, Jian Hua WANG, Shen Yi TONG

中国化学快报. 2005, 16(01): 75-77.

摘要 ( )

可视化

The macromolecular structures on nitinol surfaces were prepared by ECR microwave cold-plasma of tetraglyme conditions. The surface chemistry was characterized by high resolution ESCA. The results showed that the modified nitinol surfaces were built up mainly of -CH₂-CH₂-O- linkages and were particularly effective in preventing platelet adhesion.

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Anodic Synthesis and Characterization of Na-Pb-O, Na-Pb-Bi-O Crystals

Li Mei QIU, Fen LIU, Liang Zhong ZHAO

中国化学快报. 2005, 16(01): 78-80.

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可视化

Crystals of Na-Pb-O and Na-Pb-Bi-O were electrosynthesized on the anode from molten salts. The resulting crystals have a hexagonal structure, in which the base ions (Pb and Bi) are in high oxidation states. By using KOH/NaOH (atomic ratio K:Na=1:1) mixture as a flux,incorporation of K ions into the lattice is inhibited while incorporation of Bi ions is enhanced. The magnetic measurement shows that the Na-Pb-Bi-O crystals are dominated by diamagnetism.

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Cleavage of DNA by a New Mixed-ligand Cu(Ⅱ) Complex

Qing Hua ZHOU, Pin YANG

中国化学快报. 2005, 16(01): 81-84.

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可视化

Cleavage of DNA pUC19 by[Cu(saldien)(NH₃)]C1₂ (here, saldien=bis(salicylicdene)-diethylenetriamine) was investigated at different pHs, times, concentrations, and 37℃. It was found that the copper(Ⅱ) complex could cleave DNA without added coreactants.

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New Thiophene Derivatives with Two-photon Excited Fluorescence

Wei WANG, Guang Ming XIA, Gui Bao XU, Zhi Qiang LIU, Qi FANG

中国化学快报. 2005, 16(01): 85-88.

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可视化

Two new compounds involving a thiophene moiety named as 2,5-bis[4-(N,N-diphenylamino)styryl]thiophene (BPST) and 2,5-bis[4-(N,N-diethylamino)styryl]thiophene (BEST) have been synthesized. The two-photon absorption cross section of BPST was measured as large as 256×10^-50 cm⁴·s/photon, when it was excited by 800 nm femtosecond laser.

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Synthesis and Characterization of Two Novel High Valent Dinuclear Complexes with a Triphenolate Ligand Bearing Functional Groups

Feng SHI, Hong Yang LI, Xiao Jun PENG, Rong ZHANG, Xiao Qiang CHEN, Jiang Li FAN, Jing Nan CUI, Björn Åkermark, Li Cheng SUN

中国化学快报. 2005, 16(01): 89-92.

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可视化

Two novel high valent complexes [M₂(Ⅲ, Ⅲ)L(μ-OAc)₂]·PF₆ (M=Mn, Fe; 9) were prepared, where L was the tri-anion of 2,6-bis{[(2-hydroxy-3-(morpholin-4-yl methyl)-5-tert-butyl benzyl)(pyridyl-2-methyl)amino]methyl}-4-methyl phenol which contained additional phenolic, tert-butyl and morpholin-4-yl methyl groups compared to its parent[Mn₂(Ⅱ, Ⅱ)(bpmp)(μ-OAc₂)·CLO₄ (10).These improvements decreascd the difference beteween the mew mode and (Mn)₄ cluster (OEC in nature).

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Application of Mn(Ⅱ) as a Mimetic Enzyme of Horseradish Peroxidase

Ai Xia HAN, Li Hong NIU, Rui CHANG, Fu Shi ZHANG

中国化学快报. 2005, 16(01): 93-96.

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可视化

In this study, Mn(Ⅱ) as a mimetic enzyme of horseradish peroxidase (HRP) was applied to the determination of hydrogen peroxide (H₂O₂). The method introduced in this paper is based on Mn(Ⅱ)'s catalytic effect on the oxidation of 4-aminoantipyrine(4-AAP) with modified Trinder's reagent N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3, 5-dimethoxyaniline(DAOS) by H₂O₂.By coupling this mimetic catalytic reaction with the catalytic reaction of glucose oxidase (GOD),glucose can be detected. Under optimum conditions, the calibration graphs for the determination of H₂O₂ and glucose are in the range of 1.0×10^-3-1.0×10^-1 mol/L and 1.0×10^-3-14×10^-3 mol/L respectively. The detection limit is 5.9×10^-4 mol/L for H₂O₂ and is 9.2×10^-4mol/L for glucose.The feasibility of Mn (Ⅱ) as a HRP mimetic enzyme in practical clinical analysis has been proven in the determination of glucose in human serum. So far, Mn (Ⅱ) is the simplest and the most inexpensive mimetic enzyme.

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Novel Oxygen Storage Components Promoted Palladium Catalysts for Emission Control in Natural Gas Powered Engines

Bin ZHAO, Mao Chu GONG, Xue Song FENG, Yong Yue LUO, Yao Qiang CHEN

中国化学快报. 2005, 16(01): 97-99.

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可视化

A three-way catalyst comprised novel oxygen storage components for emission control in natural gas powered engines was prepared. The addition of novel oxygen storage components to the Pd/γ-A1₂O₃ catalysts resulted in improved activities of the fresh and aged catalyst by lowering the light-off temperature for methane in natural gas engines exhaust.

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Efficient Nd Promoted Rh Catalysts for Vapor Phase Methanol Carbonylation

Shu Feng ZHANG, Qing Li QIAN, Ping Lai PAN, Yi CHEN, Guo Qing YUAN

中国化学快报. 2005, 16(01): 100-102.

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可视化

A Nd promoted-Rh catalysts supported on polymer-derived carbon beads for vapor-phase methanol carbonylation was developed. Rh-Nd bimetallic catalysts obviously have higher activity than that of supported Rh catalyst under similar reaction condition. The difference between the activity of above two catalyst systems is clearly caused by the intrinsic properties generated by the introduction of Nd.

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Highly Effective Propylene Epoxidation over TS-1/SiO₂ Hydrothermally Treated

Wei Guo CHENG, Xiang Sheng WANG, Gang LI, Xin Wen GUO, Qing Song LIN

中国化学快报. 2005, 16(01): 103-106.

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可视化

The propylene epoxidation over TS-1/SiO₂ catalyst hydrothermally treated was investigated. It was found by EPR characterization that two types of Ti (Ⅳ)-superoxide radicals,A (g_z=2.0271; g_y=2.0074; g_x=2.0010) and B (g_z=2.0247; g_y=2.0074; g_x=2.0010), were observed for TS-1/SiO₂. The superoxo species A converted to B after TS-1/SiO₂ catalyst was hydrothermally treated. The results show that over TS-1/SiO₂ catalyst hydrothermally treated at 170℃, about 95% conversion of H₂O₂ with above 94% PO selectivity is obtained during continuous running for 300 h under the conditions of reaction temperature 45℃, 0.5 h^-1 WHSV of propylene.

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Effect of Supercritical Fluids on the Biological Activity of Absidia coerulea for the Hydroxylation of Reichsterin's Substance Acetate

Xiu Feng LIU, Hui Ming ZHU, Tuan Wei ZHANG, Bao Quan ZHANG

中国化学快报. 2005, 16(01): 107-110.

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可视化

The viability and biological activity of Absidia coerulea in compressed or supercritical CO₂ and C₂H₄ were studied. The specific activity of Absidia coerulea in 7.5MPa CO₂ and C₂H₄ at 306K can reach to 23% and 75% respectively, leading to the feasibility of using supercritical C₂H₄ as an alternative to the organic solvent in the hydroxylation of Reichsterin's substance acetate.

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Synergistic Catalytic Action of Cobalt(Ⅱ) Hydroxamates and N-Hydroxyphthalimide in the Aerobic Oxidation of p-Xylene

Jian LIANG, Jian Zhang LI, Bo ZHOU, Sheng Ying QIN

中国化学快报. 2005, 16(01): 111-114.

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可视化

The catalytic performance of a series of cobalt(Ⅱ) hydroxamates (CoL₂) and the synergistic catalytic action of the cobalt complexes combined with N-hydroxyphthalimide (NHPI) in the aerobic oxidation of p-xylene to p-toluic acid (PTA) were investigated. The results showed that the existing synergistic action in the catalytic oxidation can shorten the induction period of the radical reaction and improve the yield of PTA.

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Effect of Alkali Treatment on the Structure and Catalytic Properties of ZSM-5 Zeolite

Zi Yun LI, Xin SUN, Qiang XIAO, Shou He XIANG

中国化学快报. 2005, 16(01): 115-118.

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可视化

Catalytic properties of ZSM-5 zeolite samples pretreated with NaOH solution have been investigated. The samples are characterized by XRD, SEM, chemical analysis, and N₂ adsorption.The results indicate that mesopores are created in ZSM-5 crystals under alkali treatment without change the microporous structure and acidic strength of the zeolite, but the crystallinity is greatly decreased under severe treatment. IR indicates that the concentration of silanol is greatly enriched by alkali treatment. The etherification activities of ZSM-5 zeolites are greatly increased by alkali-treatment. The noticeably improved catalytic activity of treated samples is ascribed to the formation of mesopores and greatly enriched silanol group.

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Chlorine-radical Induced Oxidation of Glyoxal and Glyoxal-S(Ⅳ) Adducts in the Aqueous Phase

Ying LI, Yun TANG, Jia Qiang WANG

中国化学快报. 2005, 16(01): 119-122.

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可视化

A laser flash photolysis study of the reactivity of Cl with glyoxai, glyoxal mono-and dibisulfite adducts, 1-hydroxy-2, 2-diol-ethanesulfonate and 1, 2-dihydroxy-1, 2-ethanedi sulfonate in the aqueous phase was carried out. The obtained rate constants can be used for atmospheric modeling.

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Synthesis and Characterization of Chitosan-g-poly-(D, L-lactic acid) Copolymer

Hua YANG, Shao Bing ZHOU, Xian Mo DENG

中国化学快报. 2005, 16(01): 123-126.

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可视化

Biodegradable chitosan-g-poly (D, L-lactic acid) copolymers were prepared via two methods. (1) The lactide was grafted onto hydroxyl groups of chitosan by using macromolecular initiator sodium of trimethylsilyl-chitosan, (2) poly (D,L-lactic acid)(PLA) with low molecular weight can be linked to the amino group by coupling activated PLA to trimethylsilyl-chitosan. Two graft copolymers had hydrophilic-hydrophobic character and can be applied as carriers for drug delivery.

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Synthesis and Characterization of A Novel Cholesteric Liquid Crystalline Containing Carboxyl Group

Jing MA, Ying Nan XUAN, Yong HUANG

中国化学快报. 2005, 16(01): 127-130.

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可视化

A novel liquid crystal compound with a carboxyl group at one end, cholest-5-en-3-ol-(3β) hydrogen decanedioate (1) was successfuly prepared by the reaction of cholesterol with sebacoyl chloride. Its chemical structure and liquid crystalline properties were characterized by FTIR, ¹³CNMR, ¹HNMR, POM and DSC. The compound with an active carboxyl group shows themortropic liquid crystalline behaviour.

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Modulation of Tartrates with Various Counterions on the Phases of Calcium Oxalate in Gelatinous Systems

Jian Ming OUYANG, Xiang Ping LI

中国化学快报. 2005, 16(01): 131-134.

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可视化

Effect of various counterions of tartrate on the crystallization of calcium oxalate in gel system was investigated using scanning electron microscopy and X-ray diffraction. Various tartrates with hydrogen (H₂tart), sodium (Na₂tart), potassium (K₂tart), ammonium ((NH₄)₂tart), and a mixture of sodium and potassium cations (NaKtart) were considered. For H₂tart, Na₂tart, and (NH₄)₂tart, calcium oxalate dihydrate (COD) was induced. However, for K₂tart and NaKtart,calcium oxalate trihydrate (COT) was obtained.

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Preparation and Properties of Urease Immobilized onto Glutaraldehyde Cross-linked Chitosan Beads

Zu Pei LIANG, Ya Qing FENG, Shu Xian MENG, Zhi Yan LIANG

中国化学快报. 2005, 16(01): 135-138.

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可视化

Urease was immobilized onto the glutaraldehyde cross-linked chitosan beads that were prepared under microwave irradiation. The activity and the yield of activity of immobilized urease was 10.83 U/g B and 47.7%, respectively. The conditions of urease immobilization were optimized. The properties of the immobilized urease were investigated and compared with that of the free enzyme.

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Evaluation of Average Wall Thickness of Organically Modified Mesoporous Silica

Yan Jun GONG, Zhi Hong LI, Bao Zhong DONG

中国化学快报. 2005, 16(01): 139-142.

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可视化

The small angle X-ray scattering of organically modified MSU-X silica prepared by co-condensation of tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES) show negative deviation from Debye's theory due to the existence of the organic interface layer. By exerting correction of the scattering negative deviation, Debye relation may be recovered, and the average wall thickness of the material may be evaluated.

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2005年, 第16卷, 第01期　刊出日期：2005-01-20

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2005年, 第16卷, 第01期 刊出日期：2005-01-20

2005年, 第16卷, 第01期　刊出日期：2005-01-20