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Chinese Science Bulletin 1998年第5期43卷 420-424页

作者： Fuyuan Wu Borming Jahn Qiang Lin Changchun Univ Sci & Technol Dept Earth Sci Changchun 130061 Peoples R China Univ Rennes 1 F-35042 Rennes France

The orogenic belt of northern China is characterized by widely developed postorogenic Ⅰ fractionated and A-type granites in the Phanerozoic. The isotopic data display relatively high ε Nd(t) and 206Pb/ 204Pb values ... 详细信息

关键词： orogenic belt of northern China granites isotope crustal growth.

Directional growth.of Al-Mg_2Si eutectic alloy in the SZ2 unmanned spaceship

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Science China(Physics,Mechanics & Astronomy) 2003年第2期46卷 158-163页

作者：潘明祥李顺朴赵德乾汪卫华闻平俞育德聂玉昕赵生旭庄艳歆陈熙琛 Institute of Physics Extreme Conditions Physics Key Laboratory & Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080China

This paper reports the investigation results on directional growth.of Al-Mg2Si eutectic alloy in the SZ2 unmanned spaceship. The analysis shows that microgravity has influence on the directional growth.of Al-Mg2Si eutectic alloy. The eutectic colony in space-grown sample is larger than that in ground-grown sample, and the directional effect is not so good as that of terrestrial sample. But there is no obvious difference in the lamellar thickness between these samples, and lamellar interspacing in space sample is smaller than that grown on the ground. A simple discussion is done on the gravity effect on the directional growth.of Al-Mg2Si eutectic alloy.

关键词： microgravity, eutectic, directional growth.

Competitive growth.of different phases in eutectic alloys under directional solidification

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Science China(Technological Sciences) 2005年第3期48卷 270-281页

作者： LI Shuangming MA Bole LI Xiaoli LIU Lin FU Hengzhi State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi'an 710072China

By comparisons of interface growth.temperatures of different phases in eutectic systems, competitive growth.between the primary phase, halo structure and coupled eutectic has been discussed. The compositions for the formation of coupled eutectic have been discussed at the coexisting with the primary phase in eutectic under directional solidification. Solidification conditions, such as growth.rate and composition required for the formation of the primary phase, halo structure and coupled eutectic have been proposed. Numerical calculation results show that no halo structure formed in directionally solidified Sn-Pb eutectic, but in Al-Si eutectic, competitive growth.structures of the primary β-Si phase, α-Al halo structure and coupled eutectic (α+β) may exist at the hypereutectic composition between 12.6% and 25% Si. The calculated results of Al-Si eutectic fit in with the reported experiment results.

关键词： directional solidification,eutectic alloy,competitive growth.

Effects of extracellular calmodulin on pollen germination and tube growth

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Chinese Science Bulletin 1998年第2期43卷 143-146页

作者： Ligeng Ma Xiaodong Xu Sujuan Cui Daye Sun Hebei Normal Univ Mol Cell Biol Lab Shijiazhuang 050016 Peoples R China

The effects of calmodulin (CaM) antagonist W7_agarose, anti_CaM serum and exogenous purified CaM on pollen germination and tube growth.of Forsythia suspensa were studied. The pollen germination and tube growth.were inhibited or completely stopped by CaM antagonist W7_agarose. The addition of exogenous purified CaM stimulated pollen germination and tube growth. whereas the same amount of bovine serum albumin (BSA) had no effect. The inhibitory effects caused by W7_agarose and anti_CaM serum could be reversed completely by the addition of exogenous purified CaM. The tube growth.of germinated pollen was also inhibited or completely stopped by W7_agarose. The results suggest that endogenous extracellular CaM initiates pollen germination and tube growth. whereas exogenous CaM enhances the above processes.

关键词： extracellular calmodulin Forsythia suspensa pollen germination pollen tube growth.

THE VAPOR EPITAXIAL growth.OF SINGLE CRYSTAL DIAMOND FILM

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Science China Mathematics 1992年第11期35卷 1402-1408页

作者：张战李嘉孙振武马丽莹方莉俐 Zhengzhou Research Institute for Abrasives and Grinding Zhengzhou 450007 PRC

With H_2 and CH_3COCH_3 used as the source gases,the diamond epitaxlal films were obtained on the sythe siged single-crystal diamond(100),(110)and(111)faces by means of the microwave plasma-assisted chemical-vapor-deposition (CVD) method. Epitaxlal growth.spirals and growth.steps can be observed by scanning electron micrographs. Using micro Raman spectra method,we analysed the contents of graphites and other forms of carbon in the single-crystal diamond thin *** experimental results showed that there are no other forms of carbon in the epitaxial *** results of reflection electron diffraction showed that the epitaxial diainond film s on diamond(100)an(110)Surfaces are single-crystal diamond films.

关键词： homoepitaxial heteroepitaxial microwave CVD diamond film growth.

Crack growth.of plane stress state in hardening material

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Chinese Science Bulletin 1997年第17期42卷 1487-1492页

作者： Fan, TY Sutton, MA Zhang, LX Research Centre of Materials Science Beijing Institute of Technology Beijing 100081 China

THE plane stress steady crack growth.in power-law hardening materials is significant in theoretical research and practical application, especially in the application in aeronautic and aerospace industries. But people ... 详细信息

关键词： plane stress state power-law hardening steady crack growth.

THE EFFECTS OF RECOMBINANT EEL growth.HORMONE,METHYLTESTOSTERONE AND L-THYROXINE ON THE growth.OF REDSEABREAM,PAGROSOMUSMAJOR

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Chinese Journal of Oceanology and Limnology 1995年第1期13卷 86-96页

作者：徐斌葛国昌苗宏志 Fisheries College Ocean University of Qingdao Qingdao Marine Life Sciences College Ocean University of Qingdao Qingdao

The effects of recombinant eel growth.hormone (reGH).methyltestosterone (MT)and L-thyroxine (T4)on the growth.of red sea bream. Pagrosomus *** *** of reGH to fry by immersion at 2 mg 1 for 2 hevery 5 dsys resulted in significant increase in both weight and *** the condition factor (CF) diminished relative to that of similarly treated controls over the 37day treatment *** in 0.1 mg:1 T4 also resulted in significant increase in both weight and length and higher survival rate of test fry compared to the controls. Immersion in MT had less effect on growth.and high-dose resulted in high *** the second *** of 2 μg reGH(gwk)caused a significant increase in the specific growth.rate (SGR) of test red sea bream fingerlings relative to that of the controls during the 4-week treatment period and maintained the increasing trend over the post-treatment period (weeks 4-6).Injection of MT at a dosage of 1μg (gwk) resulted in a significant

关键词： growth hormone. methyltestosterone. L-thyroxine. growth. red sea bream

Rainfall infiltration on hilly slopes under various lithology and its effect on tree growth.in the dry-hot valley

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Science China(Technological Sciences) 2003年第z1期46卷 110-119页

作者： YANG Zhong, XIONG Donghong, ZHOU Hongyi & ZHANG Xinbao Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, Chengdu 610041, China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

Revegetation is very difficult in dry-hot valleys in China. Rainfall infiltration capability on hilly slopes is one of the key factors determining soil moisture conditions and tree growth.in the dry-hot valley. Low rainfall infiltration often results in soil drought on slopes under the dry-hot valleys climate. Rainfall infiltration capability varies greatly with the difference of slope lithologic porosity. The infiltration rates of five lithologic slope-types, Schist Slope, Grit Slope, Gravel Slope, the slightly eroded Mudstone Slope and the intensively eroded Mudstone Slope, are 1.40-8.67, 6.33, 0.69-2.20, 0.6-1.3 and 0.03-0.63 mm/min, respectively. With its viscid compact soil body and low infiltration capability which causes little infiltrating rainfall, mudstone slope can afford little effective supply to soil water and leads to serious drought of soil in dry seasons, resulting in cessation of growth.or even wide-spread death of trees due to physiological damage for the excessive deficit of water in dry season and also the low productivity of stands. Hence, it is extremely difficult to restore vegetation on this type of slope. The other four lithologic slope-types, however, with well-developed soil crevice, high infiltration capability and thus more infiltrating rainfall, can afford more available soil water supply and the trees on them can obtain better growth.and relatively higher productivity, compared with those on Mudstone Slope. Revegetation in dry-hot valleys is controlled by the soil moisture conditions of different slope-types, and it can be implemented by relying on the dominative life-form plant species, the suitable spatial arrangement of different life-forms of arbor-shrub-herb species, and the establishment of ecological community relationship between vegetation and soil moisture in habits. On the other hand, ground making measures for forestation and the runoff-collecting engineering measures to increase the rainfall infiltration are the major key

关键词： dry-hot valleys, lithologic property, rainfall infiltration, tree growth.

growth.OF SINGLE CRYSTALS AND PRELIMINARY ANALYSIS OF GLUCOSE ISOMERASE FROM Streptomyces M1033

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Chinese Science Bulletin 1991年第19期36卷 1646-1649页

作者：张公义牛立文黄婉治王淳刘竞崔涛刘咸安王玉珍徐洵梁栋材 Department of Biology University of Science and Technology of China Hefei 230026 PRC Structure Research Laboratory University of Science and Technology of China Hefei 230026 Biological macromolecule Research Laboratory Institute of BiophysicsAcademia SinicaBeijing 100080

Ⅰ. INTRODUCTION Glucose isomerase (EC 5.***.1.5) can catalyze the isomerization of glucose to fructose, which is the basis for the industrial production of high-fructose syrups. A number of glucose isomerases from a variety of bacterial sources have been investigated crystallographically (see Table 1 for detail). It seems that the glucose isomerase from Streptomyces rubiginosus (abbreviated to STRPR) has not the same precise relationships between the spatial structure and biological function as the one from Streptomyces olivochromogenes (abbreviated to STRPO), although those two enzymes are very

关键词： glucose isomerase enzyme single crystal growth.

CRYSTAL growth.AND PHOTOREFRACTIVE PROPERTIES OF Cu-DOPED POTASSIUM SODIUM STRONTIUM BARIUM NIOBATE

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Chinese Science Bulletin 1991年第8期36卷 637-640页

作者：姜全忠陈焕矗宋永远孙大亮许克彬徐海英余有龙袁洋 Institute of Crystal Materials Shandong University Jinan 250100 PRC Department of Applied Physics Harbin Institute of Technology Harbin 150006 PRC

With the progress of research on the applications of photorefractive (PR)effect in recent years, people paid more and more attention to the PR materials, especially to the modification of their properties, in order to... 详细信息

关键词： potassium sodium strontimn barium niobate photorefractive effect crystal growth.