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A New Ursene Type Triterpenoid from Crepis napifera

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Chinese Chemical Letters 2000年第8期11卷 711-712页

作者： wu, sh Luo, XD Ma, YB wu, DG Chinese Acad Sci Kunming Inst Bot Lab Phytochem Kunming 650204 Peoples R China

A new triterpenoid, urs-20-en-3 beta-acetoxy-22 alpha-ol, and three known compounds 3 beta-acetoxy-amyrin, 3 beta-acetoxy-lupeol, lupeol were isolated from the leaves of Crepis napifera (Franch.) Babe. Their structure... 详细信息

关键词： Crepis napifera (Franch.) Babc. Compositae triterpenoid urs-20-en-3 beta-acetoxy-22 alpha-ol 3 beta-acetoxy-amyrin 3 beta-acetoxy-lupeol lupeol

Asymmetric Meerwein-Ponndorf-Verley reduction catalyzed by a new type of chiral binaphthol-samarium complex

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Chinese Journal of Chemistry 1996年第6期14卷 561-564页

作者： Ding, ZB Cheng, KJ wu, sh FUDAN UNIV DEPT CHEMSHANGHAI 200433PEOPLES R CHINA

A new type of chiral 1,1'-binaphthol(BINOL) derived samarium complex, prepared from (R)- or (S)-BINOL and SmCl3, serves as an enantioselective catalyst for the Meerwein-Ponndorf-Verley (MPV) reduction in the presence of Molecular Sieves 4 Angstrom(MS 4 Angstrom). Moderate enantioselectivity was obtained. Kinetic studies show slight decrease of the enantiomeric excess with the conversion.

关键词： asymmetric synthesis reduction samarium reagent

PREPARATION OF Cr-POLYSTYRENE COMPLEX BY METALVAPOR SYNTHESIS

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Chinese Chemical Letters 1996年第7期7卷 679-680页

作者： wu, sh Zhu, CY Huang, WP NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

Chromium atom-hexane solution prepared in a metal atom reactor was transferred into a solution containing polystyrene in diethylene glycol dibutyl ether at -78 degrees C, followed by gently warming the mixture to 0 degrees C to react for two hows, yielding a brown-green solid product Ultraviolet-visible and infrared spectra showed that the product was a bi- (eta(6)-arene) chromium complex.

关键词： Cr PREPARATION OF Cr-POLYSTYRENE COMPLEX BY METALVAPOR SYNTHESIS

Fluorescence Quenching and Depolarization Studies on Segmental Motion of Poly (N, N-dimethylacrylamide)

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Chinese Chemical Letters 1997年第8期8卷 719-720页

作者： Zhu, CY wu, sh Li, LR NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

A new polymer, poly(N, N-dimethylacrylamide), labeled with acenaphthylene has been synthesized. The rotational relaxation time of this polymer has been studied using steady state fluorescence depolarization measuremen... 详细信息

关键词： Fluorescence Quenching and Depolarization Studies on Segmental Motion of Poly N-dimethylacrylamide

STUDIES　OF　POLYMER　IMMOBILIZED　Pd－Cu　CLUSTER　CATALYSTS　PREPARED　BY　METAL　ATOM　SYNTHESIS（MVS）

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Chinese Chemical Letters 1995年第1期6卷 71-74页

作者： wu, sh Zhu, CY Zhu, JL Zheng, XS Nankai Univ Dept Chem Tianjin 300071 Peoples R China

Metal atoms of Pd and Cu produced by coevaporation in a metal atom reactor,was solvated at low temperature. These solvated metal atoms,were immobillized in. the polymer pore structure for preparing Pd-Cu bimetallic cluster *** measurements sbowed that both Pd and Cu,were in a zero-valent state. TEM and XRD resulta indicated that the Pd-Cu cluster particles,were very small. Catalytic tests. showed that these catalysts are very active for 4-methyl-3-penten-2-one hydrogenation.

关键词： Pd IMMOBILIZED CLUSTER ATOM BY MVS Cu

Lead-promoted Barbier-type reaction of aldehydes with propargyl bromides in aqueous media

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Chinese Journal of Chemistry 1997年第4期15卷 361-365页

作者： Zhou, JY Sun, GF Zhang, MF Jia, Y wu, sh Department of Chemistry Fudan University Shanghai 2004433 China

This paper reports that the reaction of the propargyl bromides with aldehydes promoted by powdered lead in aqueous media. The selectivity and possible mechanism of these reactions are discussed. The yields of products for reaction of propargyl bromide are 31 similar to 71%. The ratios of allenyl alcohol and homopropargyl alcohol are 1:1.5 to 1:3. The product for reaction of phenyl propargyl bromide is allenyl alcohol and the yields are 52 similar to 84%.

关键词： lead reagent Barbier-type reaction propargyl bromides aqueous media

Isolation and Structure Elucidation of Autolytimycin, A New Compound Produced by Streptomyces Autolyticus JX-47

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Chinese Chemical Letters 2001年第10期12卷 903-906页

作者： Li, MG wu, sh Zhao, LX Zhang, Q Li, WJ Cui, XL Xu, LH wu, DG Jiang, CL Yunnan Univ Yunnan Inst Microbiol Minist Educ PR China Key Lab Microbial Resources Kunming 650091 Peoples R China

Autolytimycin 1 was isolated from the culture filtrate of Streptomyces autolyticus JX-47, together with two known compounds, lebstatin 2 and 17-O-demethyl-geldanamycin 3. These compounds showed the activities of anti-... 详细信息

关键词： Streptomyces autolyticus autolytimycin lebstatin 17-O-demethyl-geldanamycin

Ethnocultural heritage of the North-Eastern Caucasus as a factor of eco-tourism development

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Journal of Mountain Science 2024年第8期21卷 2810-2824页

作者： Zaburaeva Khava sh. Complex Research Institute named after Kh.I.Ibragimov of the Russian Academy of Sciences Grozny 366002Russia

The North-East Caucasus is a multi-ethnic mountain macroregion with a rich cultural heritage,insufficiently studied in the context of the ecotourism *** fill this gap and identify promising directions of environmentally safe forms of tourism,the author used in-depth review of modern literature to investigate the features of ecological tourism and the problems of preserving ethno-cultural heritage,and used historical and comparative-geographical methods to analyze the development of the tangible and intangible cultural heritage of the indigenous peoples of the North-Eastern Caucasus in different historical periods and to identify the geographical peculiarities of the distribution of historical and cultural monuments(tower buildings),pilgrimage sites and centers of traditional crafts and *** part of the planned expeditions,the author personally visited some historical monuments and handicraft centers for a deeper study of ethno-cultural *** cartographic method made it possible to visualize the *** results of the research show that the ethnocultural heritage of the North-East Caucasus is formed by material(historical and cultural monuments)and immaterial elements of culture(language,customs,traditions,ethnic identification)of those peoples,who live *** ethnocultural heritage is considered as the most important factor in the development of the tourism *** is revealed that this region has a large potential for development in various areas of *** highest concentration of religious buildings focused in mountainous *** tower structures were erected in mountainous and high-altitude *** ancient times to the present day there have been preserved various types of crafts and trades(pottery,metalworking,burka making,jewelry making,carpet weaving,gold embroidery,wood and stone carving,etc.),which can become objects of *** ethnocultural heritage of the North-East Caucasus needs to be preserved a

关键词： Mountainous districts Sustainable development Prospects Stone Towers Folk crafts

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宣纸生产工艺与润墨

中华纸业 2008年第7期29卷 64-67页

作者：吴世新泾县中国宣纸协会安徽泾县242500

介绍了中国泾县宣纸的生产原料特性及原料选择(沙田稻草优于泥田稻草),宣纸独特的加工工艺以及其润墨特色。

关键词：泾县宣纸原料工艺润墨