检索结果-南通市图书馆

Biomineralization in the La' erma Gold Deposit of the Western Qinling Mountains

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1998年第1期72卷 65-76页

作者： LIN Li and ZHU LidongDepartment of Geology, chengdu institute of technology, chengdu, Sichuan 610059 Zhang Yuxu Fei Zhenbi chengdu inst technol Dept Geol Chengdu 610059 Sichuan Peoples R China

Geological and geochemical studies and experiments on mineralization indicate that the source bed of the La' erma gold deposit in the south subbelt of the western Qinling Mountains is hydrothermal cherts in the Cambrian Taiyangding Group. Organic geochemical study of the cherts shows that the organic precursors intimately associated with gold are marine bacteria and algae. The gold content in chert,is positively correlated with the amount of bacterial and algal microfossils, and simulation experiments on biomineralization of modern bacteria and algae indicate that bacteria and algae played an important role in the formation of the La' erma gold deposit.

关键词： biomineralization La' erma gold deposit Taiyangding Group source bed

Microwave Hydrothermal Synthesis PZT of Nanometer Crystal

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & technology 2004年第5期20卷 637-638页

作者： Hongxing LIU, Hong DENG, Yan LI and Yanrong LIinstitute of Microelectronics and Solid State Electronics, University of Electronic Science and technology of China, chengdu 610054, China inst. of Microelectronics Univ. of Electron. Sci. and Technol. Chengdu 610054 China

It was focused on the applications and developments of microwave hydrothermal synthesis piezoelectric ceramic powder. The microwave hydrothermal vessel was designed and manufactured. The microwave hydrothermal synthesis system was established and the PZT piezoelectric ceramic powder was synthesized. XRD and TEM have been used to characterize the products in detail. The diameter of the PZT powder particle is from 40 to 60 nm.

关键词： Microwave hydrothermal synthesis Reaction vessel PZT

Magnetic Properties of Nanometer-Scale NiZnCu Ferrite Thin Films Fabricated by Spray-Spin-Heating-Coating Method

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & technology 2004年第1期20卷 35-37页

作者： Yulan JING, Huaiwu ZHANG, lijun JIA, Yu SHI and Yingli LIUinstitute of Information and Materials, University of Electronic Science and technology of China, chengdu 610054, China inst. of Info. and Mat. Univ. of Electron. Sci. and Technol. Chengdu 610054 China

A new nanometer-scale ferrite thin film with excellent high-frequency characteristics has been developed by the spray-spin-heating-coating method. The effects of the ion synthesis mechanism, chemical stoichiometry, fabrication method, and doping content on the magnetic properties and microstructure of the thin films have been analyzed. The films formed between 75℃ and 90℃ by spray-spin-heating-coating methods was discovered with fine grain size of about 21 nm, high saturation magnetization (4πMs) of about 6.5 kGs, coercivity of about 9.8 Oe, as well as initial permeability of about 14.0. These films can be widely used in radio-frequency integrated circuit devices.

关键词： Nanometer materials Ferrite thin film Spray-spin-heating-coating

Anti-scourability of purple soil on hillslopes with different land uses

在线全文

学校读者我要写书评

暂无评论

Science China(technological Sciences) 2003年第Z1期46卷 133-141页

作者： ZHANG Jianhui, LIU Gangcai, NI Shijun, ZHU Bo & GE Fanglong institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, chengdu 610041, China chengdu University of technology, chengdu 610059, China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China chengdu Univ technol Chengdu 610059 Peoples R China

A large-scale flume (40 cm×10 cm×10 cm) was used to determine soil anti-scourability of 4 different land uses of purple soil in hilly areas of Sichuan, China under artificial removal of vegetation to examine the effects of land uses on sediment production by runoff. The results showed that soil anti-scourability declined with the increase of slope gradients in the form of power function, but there was a significant difference in the effects of slope gradients on anti-scourability between different land uses. The ratio of the mean values of soil anti-scourability was 1︰2.2︰2.5︰3.6 for forest land, new waste pasture, old waste pasture, crop land respectively, indicating that forest and grass use can significantly improve soil anti-scourability. Compared with the observations from the runoff plots located at the same sites in this region, an inconsistent result was found between anti-scourability and anti-erodibility in hilly areas of Sichuan. Essential causes of the differences in soil anti-scourability were further discussed based on analyzing the influence of inherent soil characteristics induced by different land uses on soil anti-scourability.

关键词： sediment yield, soil anti-scourability, land use, vegetation, purple soil.

Quantum mechanics calculation of the Kubo effect for the face-centered cubic structure of nanometallic hydrogen

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第3期43卷 257-260页

作者： Shiqing Yang Haocai Wang Shiguang He Wanli Zhang Qingquan Gou Univ Elect Sci & technol China Inst Informat Mat & Engn Chengdu 610054 Peoples R China Sichuan Union Univ Inst Atom & Mol Sci High Temp & High Pressure Chengdu 610054 Peoples R China

The total energy of the cubic_octahedral structure of H\++ cluster is calculated by means of the modified arrangernent channel quantum mechanics (MACQM). The present result shows that the face_centered cubic(FCC) stru... 详细信息

关键词： metallic hydrogen clusters of hydrogen atom nanometallic materials.

ANALYSIS OF BASSET FORCE OF PARTICLE MOTION IN TURBULENT FLOWS WITH SPECTRAL METHOD

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2001年第4期13卷 88-91页

作者： Liu, Xiao-Bing Wang, Jing Li, Qing-Gang Sichuan Univ. of Sci. and technol. Chengdu 610039 China

Using the spectral method from the Lagrangian particle motion equation, the particle motion statistics in solid-liquid turbulent flows, including the particle Lagrangian energy spectrum, autocorrelation function and turbulent diffusivity, were analyzed. The effects of the Basset term on these statistics were examined. It is found that the Basset force may be neglected in the Lagrangian equation of particle motion only when a dimensionless number N is very small and the particle diameter, in general, is less than 0.1 mm. The numerical results indicate that the particle diffusivity may exceed the fluid diffusivity for significantly long period.

关键词： Turbulent flow

Pn-wave velocity and anisotropy of the western Sichuan and Longmen Mountain region,China

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2010年第11期53卷 1665-1670页

作者： Xu Yi Li ZhiWei Huang RunQiu Liu JianHua Liu JinSong Chinese Acad Sci Inst Geol & Geophys Key Lab Petr Resources Res Beijing 100029 Peoples R China chengdu Univ technol State Key Lab Geohazard Prevent & Geoenvironm Chengdu 610059 Peoples R China

Pn-wave velocity and anisotropy beneath the western Sichuan and adjacent region are inverted by a tomography method using arrival data from earthquakes recorded by the Sichuan Earthquake Network. It is followed by an analysis of the uppermost mantle structure of the Longmen Mountain region and the deep tectonics of the Ms8.0 earthquake in Wenchuan. Our results reveal a prominent velocity contrast across the Longmenshan fault: low velocities in the Songpan-Ganzi mountain range and high velocities in the Sichuan basin. They indicate that the Songpan-Ganzi mountain range is underlain by a weak uppermost mantle, which is easy to create ductile flow, whereas the Sichuan basin has a mechanically strong uppermost mantle. These features reflect a difference of the lithospheric mantle beneath tectonically active mountain range and stable basin. The boundary between the high and low velocities is coincident with the Longmenshan fault. Bordered by Wenchuan, the northern part of the boundary is parallel to the fault belt and aftershock distribution, but the southern part of the boundary deviates from the fault belt and is bent toward the Sichuan basin. The Ms8.0 earthquake in Wenchuan is located at the flexural part between them, where a strong heterogeneity is shown in the velocity variation across and parallel to the boundary. This area is reasonably believed as a potential location for regional stress accumulation and release in the Longmen Mountain region, reflecting a prominent character in the deep structure around Wenchuan. Pn-wave anisotropy reveals the mantle flow that is consistent with the eastward movement of the Tibetan Plateau. This process provided deep dynamic sourse for tectonic deformation in the Longmen Mountain region and for the occurrence of the Wenchuan Ms8.0 earthquake, but it is clearly affected by the strong lithosphere of the Sichuan basin. There is no correlation between the Pn-wave anisotropy and the Longmenshan fault, hence, this fault system is on

关键词： western Sichuan Longmen Mountain Pn velocity anisotropy Wenchuan earthquake

Scaling Behaviors of Surface Roughening of Cu Thin Films Deposited by Oblique Angle Deposition

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2012年第S1期41卷 93-96页

作者： Liu Bo Yang Jijun Tang Rui Xu Kewei Sichuan Univ Key Lab Radiat Phys & Technol Minist Educ Inst Nucl Sci & Technol Chengdu 610064 Peoples R China Nucl Power inst China Sci & Technol Reactor Fuel & Mat Lab Chengdu 610041 Peoples R China Xi An Jiao Tong Univ State Key Lab Mech Behav Mat Xian 710049 Peoples R China

Cu thin films with different thicknesses were deposited by magnetron sputtering at various oblique angle θ of incidence between the deposition flux and the substrate surface ***-section microstructure and surface morphology of the films were investigated by scanning electron microscope(SEM)and atomic force microscope(AFM),*** the scaling behaviors of film surface roughening were analyzed in terms of dynamic scaling *** the increasing of the deposition angle θ,the angleφbetween grain growth direction and substrate surface normal increased *** increasing θ in the range of<50°,the roughness exponent α increased from 0.76 to 0.82 and the growth exponent β decreased from 0.42 to ***,when θ increased to 70°,α and β changed to 0.72 to 0.61,*** evolution of the scaling exponents effectively revealed the fact that the film surface roughening arises from the competition between surface diffusion and shadowing effect.

关键词： Cu thin film surface scaling oblique angle deposition

Rapid synthesis of biodegradable poly(epsilon-caprolactone-co-p-dioxanone) random copolymers under microwave irradiation

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2010年第2期21卷 249-252页

作者： Chen, Rui Hao, Jian Yuan Xiong, Cheng Dong Deng, Xian Mo Chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China Univ Elect Sci & technol China Sch Microeletron & Solid State Elect Chengdu 610054 Peoples R China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

Biodegradable poly(epsilon-caprolactone-co-p-dioxanone)(PCDO) random copolymers have been synthesized by ring-opening polymerization of epsilon-caprolactone(CL) and p-dioxanone(PDO) under microwave *** effects of irradiation time and different CL/PDO molar feed ratios on the microwave-assisted ring-opening polymerization(MROP) of PCDO have been *** resultant products were characterized by ~1H NMR,GPC and *** was found that the polymerization was completed within 20 min at 140℃.In th...

关键词： Biodegradable p-Dioxanone Microwave irradiation Random copolymer