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Science China(Life Sciences) 2011年第11期54卷 1036-1041页

作者： WANG LiZhen ZHANG HongQuan FAN YuBo Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical Engineering Beihang University Beijing 100191 China School of Materials Science and Engineering Wuhan University o（Technology Wuhan 430000 China

Woodpeckers are well able to resist head injury during repeated high speed impacts at 6-7 m s-1 with decelerations up to 1000 *** study was designed to compare the mechanical properties,microstructures and compositions of cranial bone and beak bone of great spotted woodpecker(Dendrocopos major) and the Mongolian sky lark(Melanocorypha mongolica).Microstructures were observed using micro-computed tomography and scanning electron microscopy and their compositions were characterized by X-ray powder diffraction and Fourier-transform infrared *** high stress,the cranial bone and the beak of the woodpecker exhibited distinctive mechanical features,which were associated with differences in micro-structure and composition,compared with those of the *** optimization of bone micro-structure has enabled functional adaptation to the woodpecker's specific *** characteristic micro-structure efficiently avoids head impact injury and may provide potential clues to the prevention of brain injury using bio-inspired designs of shock-absorbing materials.

关键词： woodpecker head mechanical property micro-structure composition

Effects of returns on composition,microstructure and mechanical properties of GH4169 superalloy

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China Foundry 2017年第4期14卷 244-250页

作者： Yong-liang Pu Sheng-zhong Kou Zhi-dong Zhang Tian-wen Dong Xiao-fan Guo Hong-xia Qu State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou Universityof TechnologLanzhou 730050China Key Laboratory of Non-ferrous Metal Alloys and Processing of the Ministry of Education Lanzhou University of TechnologyLanzhou 730050China

To recycle the returned alloy effectively, effects of returns proportion on alloy composition, microstructure and compression properties of superalloy GH4169 were studied by means of scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and thermal-mechanical simulator. The results show that returns addition has no significant effect on the main alloy elements content and the principle precipitates, but increases the volume fraction of Al_2O_3 inclusions, resulting in the increase of oxygen level of GH4169 alloy. Returns addition does not change the elastic and plastic deformation process at room temperature or at 1,150 °C, but high returns proportion GH4169 alloy shows improved compression strength and yield strength. The alloy with 100% returns shows a maximum compression strength 1,153.45 MPa at room temperature, while the alloy with 80% returns has a maximum value 69.3 MPa at 1,150 °C. Returns addition increases fluctuation range and reduces the stability of yield strength and compression strength of GH4169 alloy at room temperature. It is noted that the volume fraction and the size of Al_2O_3, and the fraction of Laves phase reach their maximum values in the GH4169 alloy with 60% returns, which exhibits maximum yield strength of 516.65 MPa at room temperature and 62.17 MPa at 1,150 °C.

关键词： superalloy returns proportion composition microstructure mechanical properties

The Isotopic composition of Noble Gases in Gold Deposits and the Source of Ore-Forming Materials in the Region of North Hebei, China

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Chinese Journal Of Geochemistry 2003年第4期22卷 313-319页

作者：王宝德牛树银孙爱群李红阳 Shijiazhuang University of Economics

The source of ore\|forming materials has long been a controversial focus both in metallogenic theory and in ore\|searching practice. This study deals with the helium and argon isotopic characteristics of pyrites from 11 gold deposits and some country rocks in the gold mineralization\|concentrated areas within the three mantle\|branch structures in the region of North Hebei Province. It is indicated that \{\}\+3He/\+4He ratios in the gold deposits are within the range of \{0.93×10\+\{-6\}\}-\{7.3×10\+\{-6\}\}, with an average of \{3.55\} ×10\+\{-6\}; R/Ra=\{0.66\}-\{4.93\}, averaging \{2.53\}; \{\{\}\+\{40\}Ar/\+\{39\}Ar\} ratios vary between 426 and 2073, with the average value of \{\}\+\{40\}Ar being \{8.32\}; and the average of \{\}\+4He/\{\}\+\{40\}Ar ratios is 2.17. \{\}\+3He/ \{\}\+4He ratios in gneiss and granite in the periphery of the mining district are within the range of \{0.001×10\+\{-6\}\}-\{0.55×10\+\{-6\}\}, reflecting significant differences in their sources. \{\}\+3He and \{\}\+4He fall near the mantle, as is shown in the He concentration diagram. Studies have shown that the ore\|forming materials in this region should come from the deep interior of the Earth. With the multi\|stage evolution of mantle plume, ore\|forming fluids in the deep interior were moving upwards to shallow levels (crust). Under such circumstances, there would be inevitably occur crust/mantle fluid mixing, so their noble gas isotopic characteristics are intermediate between the mantle and the crust.

关键词： gold deposit source of 0re-forminE nmterial He,Ar isotopic composition mantle-branch structure mantle plume

Examination of Subunit composition of Bombyx Mori Silk Fibroin

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Journal of China Textile University(English Edition) 1998年第2期15卷 28-31页

作者：蔡再生于同隐 China Textile Univ Shanghai China

Main subunits of the silk fibroin were separated by GFC(gel filtration chromatography)*** nativesilk fibroin and α,c subunits were measured by gel *** aminoacid compositions of the nativesilk fibroin and α,c subunits were analyzed by means ofaminoacid *** properties of silk was inter-preted in view of subunit composition of silk fibroin.

关键词： silk fibroin subunit composition amino -acid analysis GFC SDS - PAGE.

Structure and composition of Metal-Metal Amorphous Alloys

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Chinese Science Bulletin 1994年第20期39卷 1684-1687页

作者：张守国钱存富李兰杰张东明

Many experimental results have shown that the property of amorphous alloys has certain relation with composition, because the change in composition can result in change in structure of amorphous *** in order to unders... 详细信息

关键词： rhomb unit structure model (RUSM) composition structure metal-metal amorphous alloy.

Antimycobacterial natural products from Moroccan medicinal plants: Chemical composition, bacteriostatic and bactericidal profile of Thymus satureioides and Mentha pulegium essential oils

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Asian Pacific Journal of Tropical Biomedicine 2016年第10期6卷 836-840页

作者： Marwa Chraibi Abdellah Farah Sara Lebrazi Oumaima El Amine Mohammed Iraqui Houssaini Kawtar Fikri-Benbrahim Laboratory of Microbial Biotechnology Faculty of Science and Technology Sass Sidi Mohamed Ben Abdellah University Laboratory of Aromatic Plants Medicinal and Natural Substances National Institute of Medicinal and Aromatic PlantsPhytochemistry Department

Objective: To evaluate the susceptibility of Mycobacterium aurum and Mycobacterium smegmatis in vitro to the essential oils obtained from two medicinal plants: Thymus satureioides(T. satureioides) and Mentha pulegium(M. pulegium), and to study their chemical ***: The aerial parts of T. satureioides and M. pulegium(leaves and stems) were hydro-distillated using a Clevenger-type apparatus and essential oils were analyzed and identified by gas chromatography-mass spectrometry. Antimycobacterial screening of essential oils was performed on the basis of the inhibition zone diameter by disc diffusion method against two mycobacterial strains whereas the minimal inhibitory concentration and minimal bactericidal concentration were determined by using the micro-dilution ***: Chemical analysis of their aerial part's essential oils gave as major compounds,borneol(34.26%), carvacrol(31.21%) and thymol(3.71%) for T. satureioides and R(+)-pulegone(75.48%), carvone(6.66%) and dihydrocarvone(4.64%) for M. *** their antimycobacterial effect evaluation, using the micro-dilution method,indicated that minimal inhibitory concentration values of T. satureioides essential oil ranged from 0.062% to 0.015%(v/v) and from 0.125% to 0.031%(v/v) for M. pulegium respectively against Mycobacterium aurum and Mycobacterium ***: It is clearly evident from the results obtained that the Moroccan medicinal plants have great potential to be used as anti-tuberculosis agents. These findings may help scientists to undertake several research projects to discover useful natural product as new anti-tuberculosis drug.

关键词： Thymus satureioides Mentha pulegium Essential oil Chemical composition Antimycobacterial activity

Characteristics of Elemental and Clay Mineralogical composition of Some Primitive Soils From George Island, Antarctica

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Chinese Science Bulletin 1994年第17期39卷 1481-1484页

作者：潘根兴成杰民 Department of Natural Resources and Environment Sciences Nanjing Agricultural University Nanjing 210095 PRC

Following the study on the basic physicochemical properties of some primitive soils from George. Island, Antarctica, here the authors present further data of elemental and clay mineral composition in an attempt to ill... 详细信息

关键词： clay mineralogy elemental composition primitive soils Antarctica.

Determination of carbon isotopic composition of individual light hydrocarbons evolved from pyrolysis of source rocks by using GC-IRMS

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Chinese Science Bulletin 2000年第S1期45卷 7-10页

作者： GENG Ansong XIONG Yongqiang Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China

The carbon isotopic composition of individual light hydrocarbons generated from source rocks that had been pyrolysed in vacuum glass tube were determined by using the GC-IRMS techniques. The results indicate that abundant CO2 in the pyrolysates has a remarkable effect on the determination of CH4δ13C. Running cryogenically with an initial temperature of -40℃ can effectively eliminate the effect. In addition, it conduces to measuring the δ13C of C2+ hydrocarbons by increasing the injection volume and/or absorbing CO2 with the solution of sodium hydroxide. The above measures will help to get the carbon isotopic composition of C1-C7 components, which is of great significance for gas/source rock correlation and for study on the genesis of natural gas.

关键词： pyrolysis light hydrocarbon carbon isotopic composition GC-IRMS.

Chemical composition of gas from mantle xenoliths in alkali- basalt from Damaping, Hebei

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Chinese Science Bulletin 1997年第6期42卷 470-472页

作者： Liu, G Wang, XB Li, LW State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China

WE have measured the chemical composition of the gas extracted from ortho- and clino-pyroxenes in spinel lherzolite xenolith, and from black pyroxenolite xenolith in Cenozoic alkah-basalt from Damáping, Wanquan Count... 详细信息

关键词： mantle xenolith chemical composition of gas origin of H2

High-pressure sound velocity of perovskite-enstatite and the possible composition of the Earth's lower mantle

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Chinese Science Bulletin 2000年第10期45卷 921-925页

作者： Zizheng Gong Hongsen Xie Hui Huo Fuqian Jing Jie Guo Ji’an Xu Material Laboratory of the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang China Laboratory for Shock Waves and Detonation Physics Research Southwest Institute of Fluid Physics Chengdu China Institute of Geosciences Academia Sinica Taipei China

The compressional sound velocity VP for enstatite of polycrystalline specimens were measured at pressures from 40 to 140 GPa using the optical analytical techniques under shock loading. The dependence of VP (in km/s) on Hugoniot pressure (P, in GPa) can be described by lnVP= 3.079-0.691 ln(P) + 0.094(lnP)2. VP satisfies Birch’s law: VP= 4.068 + 1.677p, where p is corresponding density, which indicated that enstatite is stable throughout the conditions of the lower mantle. The wave velocity P is 0.5% lower and the wave velocity S is 2% higher than that of PREM respectively. We concluded that the lower mantle is mainly composed of perovskite-(Mg1-x, Fex) SiO3 and only a small amount of (Mg1-x, Fex) O is allowed in it.

关键词： enstatite sound velocity high-temperature and high-pressure composition of the Earth’s interior.