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A NOVEL STEROID FROM EICHHORNIA CRASSIPES

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Chinese Chemical Letters 1991年第7期2卷 509-512页

作者： Hou Ming wu Hui Qiang ZHOU Sheng yu HUANG Kan MA Xia Fei LAO State Key Laboratory of Bio-organic and Natural Products Chemistry shanghai institute of Organic Chemistry,academia sinica 345 LingLing Lu,shanghai 200032Shu Wen YU Wen Hao SUN Zi Wen YU shanghai institute of Plant Physiology academia sinica,shanghai 200032

6 -Hydroxy-stigmasta-4,22-diene-3-one 1,a novel steroid, was isolated from the Eichhornia *** structure was deter- mined by ~1H and ^(13)C NMR spectroscopy and further confirmed by authen- tic sample,which was synthes... 详细信息

关键词： A NOVEL STEROID FROM EICHHORNIA CRASSIPES

EFFECT OF REINFORCEMENT VOLUME FRACTION ON PRECIPITATION IN MATRIX OF SiC_p/AI COMPOSITE

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Acta Metallurgica sinica(English Letters) 1993年第8期6卷 161-167页

作者： LIN junshan LI Pengxing wu Renjie shanghai Jiao Tong University,shanghai,China postdoctoral,institute of Composite Materials,shanghai Jiaotong University,shanghai 200030,China shanghai Jiaotong Univ Shanghai China

The differential scanning calorimetric(DSC) and transmission electron microanalysis (TEM) techniques were used to study the kinetic process of precipitation in matrix of cast SiC_p/2024 *** results showed that precipitation reactions of GP zone and intermediate phase S'(Al_2CuMg)in the composites were accelerated compared with SiC-free material,the peak temperatures of both reactions were *** reaction enthalpies of both the GP zone and intermediate phase S' formation in the matrix were substantially decreased after the addition of *** analysis found that the alloying element Mg segregated at the SiC/Al interfaces,and was depleted in the matrix near the *** precipitation-free zones(PFZ) and precipitation-sparse zones(PSZ) formed near the interfaces,as a results,the volume fraction of precipitates in matrix was reduced.

关键词： SiC_p/2024 composite differential scanning calorimetry precipitation in matrix

Studies on nucleic acid chemistry——Ⅶ. Synthesis of four oligoribonucleotides of dihydrouridine (D) loop of yeast alanine transfer RNA

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Chinese Journal of Chemistry 1986年第4期4卷 358-369页

作者： YANG Bing-Hui HUANG Jian-Hua ZHOU Feng-Yi BAO Jian-Shao LAO Xia-Fei wu Lian-Fen SHEN Nan-Zhen WANG Shu-ju YANG Zai-Wan LU Ren-Rong TU Chuan-Zhong WANG Yu shanghai institute of Organic Chemistry, academia sinica, shanghai shanghai institute of Organic Chemistry Academia Sinica Shanghai

This article described the preparation and the protection of 3'-DMP and dihydrouridine（Dr） as well as the synthesis of four oligoribonucleotides composed of them. DMP and Dr were obtained by hydrogenation of 3'-UMP and Ur under acidic conditions inthe presence of platinum dioxide. They were monomethoxytritylated and benzoylated to （MeOTr）-Dbzpand （MeOTr） Dbz2, respectively. The latter was converted to Dbz2by demonomethoxytrityla-tion. The oligoribonucleotides containing DMP or Dr-ApGpD, DpApG, ApGpDpC and ApGpDp-CpGpG were synthesized via phosphodiester approach and DCC was used as condensing *** was also synthesized via phosphotriester approach and TPST, MSTe, MSNI and MSNTwere used as condensing reagents for a preliminary comparison of the coupling yields. These synthetic oligoribonucleotides were checked for purity and nucleotide sequences as *** and DpApG had been used for enzymatic synthesis of *** had been in turn successfully used for the total syntheses of the 5'-half molecule and the wholemolecule of yeast alanine t--RNA.

关键词： Studies on nucleic acid chemistry Synthesis of four oligoribonucleotides of dihydrouridine acid

Structure and Regulation of Phosphoenolpyruvate Carboxylase from Sorghum Leaves

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植物生理与分子生物学 1988年第3期 308-312页

作者： SHI Jiao-Nai wu Min-Xian JIAO Jin-An shanghai institute of Plant Physiology, academia sinica, shanghai 200032

Phosphoenolpyruvate carboxylase （ortho-phosphate: oxaloacetate carboxylase, EC 4.11.31, PEPCase）, an enzyme widely occurringin bacteria, algae and plants, is an importantcarboxylating enzyme serving a variety of func-tions ranging from photosynthetic carbon dioxidefixation to nitrogen assimilation （Latzko andKelly 1983, O'Leary 1982）. It is a key regula-tory enzyme in both C4and CAM photosyn-thesis. In C4plants, PEPCase is localized inthe mesophyll-cell cytoplasm and catalyzesthe conversion of PEP and bicarbonate to

关键词： Structure and Regulation of Phosphoenolpyruvate Carboxylase from Sorghum Leaves

Conus Peptides-A Rich Pharmaceutical Treasure

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Acta Biochimica et Biophysica sinica 2004年第11期36卷 713-723页

作者： Cheng-Zhong WANG and Cheng-wu CHIinstitute of Biochemistry and Cell Biology, shanghai institute of Biological Sciences, the Chinese Academy of Sciences, shanghai 200031, China institute of Neuroscience, the Chinese Academy of Sciences, shanghai 200031, China institute of Protein Research, Tongji University, shanghai 200092, China institute of Biochemistry and Cell Biology Shanghai Institute of Biological Sciences the Chinese Academy of SciencesShanghai 200031 China institute of Neuroscience the Chinese Academy of SciencesShanghai 200031 China institute of Protein Research Tongji UniversityShanghai 200092 China

Marine predatory cone snails (genus Conus) with over 500 species represent what is arguably the largest single genus of marine animals alive today. All Conus are venomous and utilize a complex mixture of Conus peptide... 详细信息

关键词： Conus peptide conotoxin neuropathic disorder pharmaceutical potency

THE STUDY OF LATTICE MATCH IN GaInAsP/InP HETEROjuNCTION LPE LAYERS

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电子科学学刊(英文版) 1986年第1期3卷 76-81页

作者：杨易邬祥生李润身谭儒环李允平水海龙 shanghai institute of metallurgy academia sinica shanghai institute of metallurgy academia sinica

The effects of the growth conditions of two-phase solution liquid phase epitaxy(LPE)(*** temperature,cooling rates and solution composition)on lattice mismatch and band-gapwavelength in GaInAsP/InP heterojunction LPE layers have been investigated by X-ray double-crystal diffractometry and double-beam *** stress in the grown interface freeof misfit dislocations and lattice mismatch at growth temperature have been calculated.

关键词： diffractometry epitaxy mismatch prepare 半导体学报 narrow radius graded wafer analogous

无用灯光的退激发作用及其对激光器贮能的影响

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中国激光 1992年第2期19卷 88-91页

作者：吴光照中国科学院上海光机所 201800

本文针对氙灯泵浦的Ti:Al_3O_3,Cr:BeAl_2O_4和Nd:YAG激光器定量地计算了退激发的几率。结果指出,对Cr:BeAl_2O_4,退激发作用的影响可以忽略不计。而对于Nd:YAG和Ti:Al_2O_3,退激发作用能使激发态粒子数分别减少18％和30％。

关键词：灯泵激光器灯光退激发激光器储能

INTERACTION　OF　PARTICLES　WITH　A　SOLIDIFIED　INTERFACE　DURING　SOLIDIFICATION　OF　METAL　MATRIX　COMPOSITE　REINFORCED　WITH　PARTICLES

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Acta Metallurgica sinica(English Letters) 1996年第1期9卷 71-78页

作者： CHU Shuangjie WANG Haowei wu Renjie LIN Xiaotang(institute of Composite Materials,shanghai Jiaotong University,shanghai 200030,China shanghai Jiaotong Univ Shanghai China

The interaction of particles with a solid-liquid interface during solidification of metal matrix composites has been investigated theoretically in this *** to the presence of particles in the melt,the shape of the solidification front and solute concentration field in front of solidification interface have been disturbed The thermodynamic method was employed,and a mathematical expression of the shape of the solidification interface and solute concentration field were ***,a theory is developed for evaluation of critical velocities of particles pushed by the solidification interface.A numerical simulation is done in which the critical velocity is evaluated as a function of particle size,thermal conductivity,diffusion coefficient,temperature gradient at the solidification front,the solid-liquid interfacial energy and the melt *** critical velocity is shown to be closely linked to the shape of the solidification interface and solute concentration field, and hence all the parameters also affect the shape of the solidification interface and solute concentration field of the front.

关键词： metal matrix composite solid-liquid interface interaction solidification

STUDIES ON THE SITE OF DEGRADATION OF ORGANOPHOSPHATE INSECTICIDES IN MOSQUITOES

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Chinese Science Bulletin 1988年第9期33卷 775-778页

作者：吴敦肃 shanghai institute of Plant Physiology Academia Sinica

Malsumura and Hogendijk (1964) found that there was a difference in phosphatase activity between organophosphorus (OP)-resistant and sensitive (SEN) strains of houseflies. Welling et al. (1971) found that the resistant strain of houseflies could degrade paraoxon to produce biethyl phosphonic acid. Oppenoorth and Voerman (1975) found that in OP-resistant strain of Muzus persicae, phosphatase could degrade the malathion to produce bimethyl phosphonic acid. From the above studies,

关键词： degrade filtration contained incubation mentioned Phosphatase Culex spots metabolite insoluble