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A new cucurbitane triterpenoid from Momordica charantia

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Chinese Chemical Letters 2007年第7期18卷 843-845页

作者： Qing Yan Li Hong Liang Hu Biao Chen Bin Wang yu ying Zhao Department of Natural Medicines School of Pharmaceutical Sciences Peking University Health Science Center Beijing 100083 China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Science Peking University Beijing 100083 China

One new cucurbitane-type triterpenoid saponin, 5β,19-epoxycucurbita-6,23-diene-3β,19,25-triol-3-O-β-D-allopyranoside （1）,named momordicoside P was isolated from the fresh fruits ofMomordica charantia. The structu... 详细信息

关键词： Momordica charantia Cucurbitane triterpenoid Saponin Momordicoside P

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钛合金梁式管接头密封性能的结构优化设计

哈尔滨工业大学学报 2022年第1期54卷 73-79页

作者：崔颖于颖嘉张宏翔钟兢军大连海事大学船舶与海洋工程学院大连116026 上海海事大学商船学院上海201306

为优化具有椭圆弧凹槽的航空钛合金梁式管接头,基于ABAQUS软件建立了梁式管接头弹塑性接触有限元模型,得到了阴、阳接头两道密封处的接触应力分布与接触带宽。综合考虑梁式管接头宏观几何结构与接触面微观形貌,以S指数为密封性能评价指... 详细信息

为优化具有椭圆弧凹槽的航空钛合金梁式管接头,基于ABAQUS软件建立了梁式管接头弹塑性接触有限元模型,得到了阴、阳接头两道密封处的接触应力分布与接触带宽。综合考虑梁式管接头宏观几何结构与接触面微观形貌,以S指数为密封性能评价指标,利用Isight软件和多岛遗传算法得到了密封性能最优的阴接头几何构型。对最优结构的有限元数值模拟表明,优化结构的S指数比原型和数据库最大值结构分别提高102.2%和53.1%,其最大接触应力与接触带宽明显增大,优化结构的密封性能显著提高。最优结构的S指数与优化方法的预测值吻合良好,从而验证了优化方法的有效性和结构优化设计的准确性。采用的S指数密封评价准则相比于传统单纯以接触应力或接触带宽评价密封性能的方法更全面考虑了密封结构的宏观与微观特征,为梁式管接头密封结构优化设计提供了可量化的密封性能目标函数。应用Isight软件与多岛遗传算法可提高计算效率与优化精度。

关键词：梁式管接头密封性能 S指数多岛遗传算法结构优化

维普期刊数据库博看期刊

Cloning and Sequence Analysis of a Novel Cold-Adapted Lipase Gene from Strain lip35 (Pseudomonas sp.)

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Agricultural Sciences in China 2008年第10期7卷 1216-1221页

作者： WANG Cai-hong GUO Run-fang yu Hong-wei JIA ying-min Department of Biology Engineering Agricultural University of Hebei Baoding 071000 P.R.China

A combination method of the usual-PCR and reverse-PCR for the cloning of a novel lipase gene directly from the total genomic DNA of strain lip35 （Pseudomonas sp.） is described, whereby a lipase gene （lip） was cloned directly from genomic DNA. The sequence data have been deposited in the GenBank and EMBL data bank with the accession number EU414288. The nucleotide sequence showed a major open reading frame encoding a 59-kDa protein of 566 amino acid residues, which contained a lipase consensus sequence GXSXG. The lipase lip had 74 and 70% homologies with the lipases of an uncultured bacterium and P. fluorescens PfO-1, respectively, but it did not show any overall homology with lipases from other origins. The functional lipase was obtained when the lip gene was expressed in Pichia pastoris GS115.

关键词： PCR reverse-PCR lipase gene clone sequence analysis

Direct chemical vapor deposition growth of graphene on Ni particles using solid carbon sources

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Rare Metals 2021年第8期40卷 2275-2280页

作者： Feng Zheng ying Liu Cai-Li Zhang Jian Wang Nan Dong Pei-De Han Yan-Xia Wu yu-Cheng Wu College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Institute of New Carbon Materials Taiyuan University of TechnologyTaiyuan030024China

Graphene has attained a considerable amount of popularity as an attractive ultra-thin reinforcement for nickel(Ni)matrix composites in recent ***,its excellent reinforcement efficiency is suffered from the agglomeration of graphene nanosheets in manufacturing process and the poor bonding strength of graphene with Ni *** overcome these two problems,one of the efficient strategies is to in-situ grow graphene reinforcements on Ni particles for powder *** work aims to synthesize uniform graphene@Ni composite particles by using polymethyl methacrylate(PMMA)as the solid sources for chemical vapor deposition(CVD)*** results demonstrate that few-layer or multilayer graphene with different morphologies can be grown on the particles by controlling the PMMA content and annealed temperature,*** optimum condition for the formation of high-quality few-layer graphene is 1.0 mg·ml^(-1) PMMA and 900℃.A competition mechanism rises from the growth kinetic,and the spatial confinement effect has led to the formation of graphene with different microstructures and morphologies.

关键词： Graphene Ni particles Solid carbon sources Growth mechanism

Microstructure and mechanical properties of high-strength high-pressure die-cast Mg–4Al–3La–1Ca–0.3Mn alloy

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Rare Metals 2021年第10期40卷 2956-2963页

作者： Peng-Fei Qin Qiang Yang yu-ying He Jing-Huai Zhang Jin-Shu Xie Xi-Ru Hua Kai Guan Jian Meng Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering University of TokyoTokyo 113-8654Japan

A new high-pressure die-cast(HPDC) Mg–4 Al–3 La–1 Ca–0.3 Mn(ALaX431) alloy with high strength has successfully been fabricated. This HPDC alloy in peakaged state exhibits tensile yield strength(TYS) of 220 MPa at room temperature and TYS of 145 MPa at 250 ℃,higher than the corresponding strength of HPDC Mg alloys reported so far. These high strengths are mainly due to the formation of fine grained structure, semi-continuous reticular structure consisting of stable Al_(3)La and(Mg,Al)2 Ca particles along grain boundaries and numerous nanoscale Al_(2)Ca precipitates within grains. Due to its higher strength than existing HPDC Mg alloys, the new developed alloy has great application potential.

关键词： Magnesium alloys High-pressure die-cast Mechanical property Intermetallic phase

Mutation analysis and prenatal diagnosis of EXT1 gene mutations in Chinese patients with multiple osteochondromas

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Chinese Medical Journal 2011年第19期124卷 3054-3057页

作者： ZHU Hai-yan HU Ya-li YANG ying WU Xing ZHU Rui-fang ZHU Xiang-yu DUAN Hong-lei ZHANG ying ZHOU Jin-yong Prenatal Diagnosis Center Department of Obstetrics and Gynecology the Affiliated Drum Tower Hospital of Nanjing University School of Medicine Nanjing Jiangsu 210008 China Department of Laboratory Medicine the Affiliated Drum Tower Hospital of Nanjing University School of Medicine Nanjing Jiangsu 210008 China

Background Multiple osteochondromas （MO）, an inherited autosomal dominant disorder, is characterized by the presence of multiple exostoses on the long bones. MO is caused by mutations in the EXT1 or EXT2 genes which encode glycosyltransferases implicated in heparin sulfate *** In this study, efforts were made to identify the underlying disease-causing mutations in patients from two MO families in *** Two novel EXT1 gene mutations were identified and no mutation was found in EXT2 gene. The mutation c.497T〉A in exon 1 of the EXT1 gene was cosegregated with the disease phenotype in family 1 and formed a stop codon at amino acid site 166. The fetus of the proband was diagnosed negative. In family 2, the mutation c. 1430-1431delCC in exon 6 of the EXT1 gene would cause frameshift and introduce a premature stop codon after the reading frame being open for 42 amino acids. The fetus of this family inherited this mutation from the *** Mutation analysis of two MO families in this study demonstrates its further application in MO genetic counseling and prenatal diagnosis.

关键词： multiple osteochondromas EXT1 mutation prenatal diagnosis

Numerical Study of Convective and Radiation Heat Transfer Characteristics in an Upward-Facing Cylindrical Cavity under Back-Side Windy Condition

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Journal of Thermal Science 2021年第1期30卷 302-312页

作者： WANG Zehui WU Kefeng WANG Ti XIA Liangwei yu Qiang HUANG ying SUN Hao WEI Guohua GUAN Jingyu YAN Yanfei Guangdong Datang International Leizhou Power Generation Company LTD Zhanjiang 524255China State Key Laboratory of Efficient and Clean Coal-fired Utility Boilers Harbin 150046China Harbin Boiler Co LtdHarbin 150046China

Under the back-side windy condition,the convection and radiation heat transfer characteristics in an iso-flux upward-facing cylindrical cavity were studied by three-dimensional numerical *** impacts of cavity tilt angle,wind incident angle and wind speed on convection and radiation heat transfer Nusselt number Nuc and Nur were analyzed,and the possible explanations for their impacts were *** show that due to the disturbance of wind,the influence of cavity tilt angle becomes more complicated and is related to wind incident angle and wind *** variation of Nuc or Nur with wind incident angle is different for different cavity tilt *** of the changes of cavity tilt angle or wind incident angle,the Nuc increases with the wind speed while the Nur presents a declination with the increasing of wind ***,compared with cavity tilt angle and wind incident angle,wind speed may be the dominant factor affecting or controlling the convective and radiation heat transfer of cavity.

关键词： upward-facing cylindrical cavity back-side wind convective heat transfer radiation heat transfer numerical simulation

Isolation and Characterization of Proteins Interacting with Activin Type Ⅱ Receptors

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Chemical Research in Chinese Universities 2006年第2期22卷 217-220页

作者： LIU Biao BAO Yong-li WEI Zhuang WU Yin MENG Xiang-ying LI yu-xin YIN Wei-tian Department of Hand Surgery China-japan Union Hospital Jilin University Changchun 130031 P. R. China Institute of Genetics and Cytology Northeast Normal University Changchun 130024 P. R. China

Regulation of the number of aetivin receptors that are present in the cell membrane plays a key role in the modulation of cellular responses to activin. In order to find the regulators, a novel protein ARIPzip, interacting with activin type II receptors, was searched and identified by using yeast two-hybrid screening. ARIPzip is a splicing variant of ARIP2. This has been discussed previously. ARIPzip can specifically interact with ActR Ⅱ A, and is widely distributed in mouse tissues. Overexpression of ARIPzip can cause the activin-induced transcriptional activities to increase in a dose-dependent manner while the overexpression of ARIV2 can decrease these activities. These data suggest that the C-terminal rezions of ARIP2 and ARIPzip are involved in the regulation of activin signaling.

关键词： Activin Activin receptor Ⅱ A( ActR Ⅱ A) Activin receptor interaction protein(ARIP)

The Response of Winter Wheat Root to the Period and the After-Effect of Soil Water Stress

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Agricultural Sciences in China 2006年第4期5卷 284-290页

作者： YANG Gui-yu LUO yuan-pei LI Bao-guo LIU Xiao-ying China Agricultural University Beijing 100094 P.R. China Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

To reveal the period and after-effect of soil water stress on winter wheat, the article employs the experiment results carried out in the greenhouse. The results showed that the root-restricted weights varied with stress degrees and stress times during and after water stressing. In the course of stress, the chief reason resticting the weight of root was the stress intensity at this time, and that of severe stress treatment was larger than that of mild stress treatment. After water stress was relieved, the results of the after-effect of soil water stress on root growth were that, the stress intensity of short-time and mild stress was larger than that of long-time and severe stress. Comparing two-stage stress intensities, root-restricted weight resulted from after-effect intensity of stress under all of the short-time treatment, and the mild and the long-time stress treatments, while that resulted from the period stress intensity under the severe and the long-time stress treatments. In general, the effects of water stress on root were attributed to the three factors, a formed basis in the previous stage, the after-effect of water condition before this stage and influence of water in this stage, which lead to the characters of root in the whole growth stage.

关键词： the period of stress after-effect of stress soil water root winter wheat