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图书情报工作动态 1996年第3期 6-12页

作者： xu,y 孟连生美国加利福尼亚州立大学图书馆中国科学院文献情报中心

Distribution　of　heavy-metals　in　the　Grand　Canal(Hangzhou　section)and　its　contributing　factors

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Journal of Environmental Sciences 1997年第3期9卷 12-24页

作者： Weng Huanxin, Zhang Dengrong Department of Earth Sciences, Zhejiang University, Hangzhou 310027, China Charlie y.xu Department of Geological Sciences, University of Illinois at Chicago. U.S.A.

The Grand Canal (Hangzhou section), People's Republic of China, has been highly contaminated by heavy metals from both industrial and municipal sources since 1950s. This study investigated the distribution of heavy metals including As, Cr, Cd, Cu, Ni, Pb, and Zn. The results showed that these metals are largely accumulated in the top 0 3 meter layer of the river *** the contamination, heavy metal concentrations in solution are increased in some locations only. The only exception is Zn whose concentrations are extremely high both in solution and in the top layer sediment. The top layer sediment appears to have reached almost its sorption capacity with respect to aqueous Zn. The extent of contamination is in the sequence of Zn>Cu>Pb>As>Cd. It is speculated that Cu distribution has been significantly affected by its binding to organic matter in the top layer sediment. Based on Pb distribution in both water and sediment, it is suggested that Pb transport in the canal is associated with colloids or particles suspended in water. The study showed that the top layer sediment in the Grand Canal serves as a sink to anthropogenic contaminants consisting of heavy metals as well as organic compounds.

关键词： heavy metal distribution contributing factor the Grand Canal (Hangzhou section).

Fe-Cr-y_2O_3 MICRO-CRySTALLINE COATINGS DEPOSITED By SERIES ELECTRO-PULSE DISCHARGE

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Acta Metallurgica Sinica(English Letters) 2002年第4期15卷 331-338页

作者： Q. xu,y.D. He,D.R. Wang,H.B. Qi,Z.W. Li and W.Gao Beijing Key Laboratory for Corrosion, Erosion and Surface Technology, University of Science and Technology Beijing, Beijing 100083, China Department of Chemical and Material Engineering, The University of Beijing Key Laboratory for Corrosion Erosion and Surface Technology University of Science and Technology Beijing

A new technique-series electro-pulse discharge (SEPD)-was developed as a sur-face coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate alloy as an induction electrode. Fe-Cr and Fe-Cr-y2O3 micro-crystalline coatings were deposited on stain-less steel (Fe-18Cr-8Ni) surfaces. Oxidation at 950℃ in ambient air showed that the coatings greatly improved the oxidation resistance of the steel. The addition of dis-persed y2O3 nano-particles into the alloy coatings was found to further reduce the scaling rate and enhance the adhesion of oxide scales.

关键词： series electro-pulse discharge Fe-Cr-y2O3 micro-crystalline al-loy coating high-temperature oxidation

Spike waves and synaptic ultrastructure in human epileptic brains

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中华医学杂志(英文版) 1996年第5期109卷 392-392页

作者： G Li y Tan y Wang Q Bai y xu y Sun B Qu Beijing Neurosurgical Institute.

OBJECTIVE To find morphological changes of synapses related to the spike discharge by observation on ultrastructures of the EEG spike foci of cerebral *** AND METHODS The cerebral cortexes were obtained surgically from the EEG spike (recorded by flaky silver electrodes on the surface of cortexes) foci and nonspike areas within the limits of the brain tissue that would be removed in 20 cases of human epilepsy, and were processed for transmission electron microscopic (TEM) *** In the spike foci, presynaptic terminals of axospinal asymmetric synapses were obviously swollen but postsynaptic spines were relatively unaffected. In these synapses, the synaptic vesicles remarkably decreased in number and accumulated predominantly at the presynaptic membranes or aggregated. Similar changes were observed in the presynaptic terminals of the axospinal asymmetric synapses in the nonspike areas but were of milder degree than in the spike *** Axospinal asymmetric synapses may release a large quantity of excitatory neurotransmitters, which may result in epileptic abnormal electric activities during seizure.

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THz Oscillations in a GaN Based Planar Nano-Device

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Journal of Computer and Communications 2013年第7期1卷 50-53页

作者： K. y. xu y. N. Wang Z. N. Wang J. W. Xiong G. Wang Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou China 2State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou China.

Gunn oscillations in a GaN based planar nano-device have been studied by ensemble Monte Carlo (EMC) method. Simulation results show that when the channel length of the device reduces to 450 nm, THz oscillations (about 0.3 THz) can be obtained. Also the phase of the oscillations can be controlled by the initial conditions that excite the Gunn domains. Moreover, through adjusting the phase difference between the oscillations in a double-channels device, which attained by parallel connecting two single-channel devices, the frequency of the device shifts from 0.3 THz to 0.6 THz. This phenomenon remains in devices with shorter channel-length, unless the channel-length is too short to support Gunn oscillations. The possible underlying mechanisms are also discussed.

关键词： THz Oscillation Gunn Monte Carlo GaN Planar Nanodevice

Integrated design and study of internal structure of Shanghai yangtze River Tunnel

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Integrated design and study of internal structure of Shangha...

作者： y.M.Di,Z.H.yang&y.xu Shanghai Tunnel Engineering & Rail Transit Design and Research Institute,Shanghai,P.R.China

With regards to the tunnel clearance,space arrangement of Shanghai yangtze River Tunnel,and comprehensively considering of the requirements of construction method and schedule to the internal structure, the road deck slab,smoke duct slab,drainage pump house and cross passages are designed integrally,which achieves good technical and economic benefits.

关键词： frame Integrated design and study of internal structure of Shanghai yangtze River Tunnel

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速度变化对AVO的一些影响及其解释

世界石油科学 1994年第4期 19-23页

作者： xu,y 孙馥莉

原位热敏凝胶瘤内注射后肿瘤坏死因子α的抗肿瘤活性

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中国医药工业杂志 2014年第1期45卷 8-8页

作者： xu y

采用开环聚合法（ROP），以β-丁内酯和丙交酯为原料，聚乙二醇为引发剂，Sn（Oct）2为催化剂，合成了一种具有生物降解和生物相容性的三嵌段共聚物（PBLA—PEG-PBLA），并用-HNMR、凝胶渗透色谱法（GPC）和差示扫描量热法进行表征。结... 详细信息

采用开环聚合法（ROP），以β-丁内酯和丙交酯为原料，聚乙二醇为引发剂，Sn（Oct）2为催化剂，合成了一种具有生物降解和生物相容性的三嵌段共聚物（PBLA—PEG-PBLA），并用-HNMR、凝胶渗透色谱法（GPC）和差示扫描量热法进行表征。结果表明，所得共聚物的临界胶束浓度为0．96x10～mg／ml，胶束的水合半径108nm。用其制备了载肿瘤坏死因子仪（TNF-α）的原位热敏水凝胶，用于瘤内注射局部递送药物。

关键词：肿瘤坏死因子α 热敏水凝胶抗肿瘤活性注射原位三嵌段共聚物临界胶束浓度差示扫描量热法

Production,Characterization and Application of Low-Dimensional ZnO Nanostructures for Bio-molecular Detection

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Production,Characterization and Application of Low-Dimension...

Boosting Photocatalytic Performance of Cu-Mn Co-doped CeO_(2) Nanoparticles for Tetracycline Degradation

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作者： y.C.Liu~* y.W.Chen C.S.xu G.y.Shan X.Hong y.J.Li (Center for Advanced Optoelectronic Functional Material Research,Northeast Normal University,Changchun 130024,PRC)

ZnO nanostructures,as versatile semiconductor materials,have become the important functional building blocks in optoelectronic *** we are concerned with recent research development with respect to the various low-dimensional ZnO nanostructures and ZnO-based *** attention has been paid to their preparation method, growth mechanism,controllable morphology,optoelectronic properties and applications in *** success in fabricating diverse ZnO nanostructures including nanowires, nanorods,nanotubes and so on has been represented in *** nanostructures endow ZnO with special physical and chemical properties and open up new possibilities for potential applications in bio-molecular *** into the growth and optoelectronic properties of ZnO nanostructures will advance the development of nanoscience and nanotechnology.

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 42-48页

作者： xu Rongqi MI Jianxin WANG Shulin xu Man ZHU Li BAI Lei TANG Dandan LEI yu Engineering Research Center of Environmental Materials and Membrane Technology of Hubei Province School of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Shaanxi Coal Chemical Industry Technology Research Institute Co. Ltd.Xi’an 710100China

Cu-Mn co-doped CeO_(2) photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading *** and TEM results showed that Cu and Mn were successfully co-doped into CeO_(2) without forming heterostructure,XPS and photoelectrochemical results revealed that Mn ions doping amplified the generation of photo-induced charge carriers,while Cu ions doping significantly facilitated the interfacial charge transfer ***,the optimized Cu3Mn2CeO_(2) nanoparticles exhibited the highest TC removal efficiency,achieved a rate of 78.18%and maintained a stable cycling performance.

关键词： photocatalyst co-doped charge separation water treatment