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PREPARATION OF MULTI-WALLED CARBON NANOTUBEs UsING NiO CATALYsT sYNThEsIZED BY hYDROThERMAL METhOD

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Acta Metallurgica sinica(English Letters) 2003年第5期16卷 416-420页

作者： Y.J.Zhu Y.L.Chen X.M.Xue Y.M.Chen C.Y.Wu T.C.Kuang s.h.li h.Y.Zhang DepartmentofAppliedPhysics GuangdongUniversityofTechnologyGuangzhou510090China CenterofAnalysisTesting GuangdongUniversityofTechnologyGuangzhou510O9OChina FacultyofMaterialandEnergy GuangdongUniversityofTechnologyGuangzhou510090.China

The Ni(Oh)2/siO2 binary colloid was prepared using Ni(NO3)2.6h2O and (C2h5O)4siO4 as starting materials and was used to form NiO/siO2. composite powder by hydrothermal method and desiccant method in open air respectively. Multi-walled carbon nanotubes (MWCNTs) were synthesized respectively by chemical vapor deposition using the NiO/siO2 catalyst prepared by different methods. The phase and morphology of the catalysts and the morphology, output yield and purity of MWCNTs were compared by XRD, TEM and sEM. The results show that the catalyst powder prepared by hydrothermal method, compared with that by desiccant method, is smaller, better dispersion and has stronger catalytic activity. Pure MWCNTs with smaller tube diameter and narrow range could be obtained at a high yield using that NiO/siO2 powder prepared by hydrothermal method as catalyst.

关键词： hydrothermal method dry method at atmosphere carbon nan- otube catalytic pyrolysis

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Three-Phase switch-Mode Rectifier Constructed using single-Phase Modules

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Three-Phase Switch-Mode Rectifier Constructed using Single-P...

2002年IEEE十区计算机、通信、控制和电机工程会议

作者： s.h.li h.Y.Tsai C.M.liaw Department of Electrical Engineering National Tsing hua University hsinchu Taiwan China Department of Electrical Engineering National Tsing hua University hsinchu Taiwan China Department of Electrical Engineering National Tsing hua University hsinchu Taiwan China Ph.D. Member IEEE

A three-phase (3φ)switch-mode rectifier(sMR)constructed using single-phase (1φ) modules ispresented in this paper. The AC sides of three modulesare △-connected, with proper control, good powerquality iu line drawn currents under well-regulatedDC output voltage is obtained. As one module faultoccurs,the proposed 3φsMR becomes *** the worst case, when two constituted 1φmodulesare faulted, the proposed 3φsMR will be operated as1φsMR to continuously supply regulated DC voltageoutput. As to the control aspect, the dynamic model ofthe 3φsMR under nominal operating condition isestimated. And accordingly, a feedback controller isdesigned to meet the given voltage regulation controlspecifications. Then a robust controller is furtherdeveloped to reduce the control performancedegradation due to the changes of operating conditionand number of connected modules.

关键词： sMR Three-Phase switch-Mode Rectifier Constructed using single-Phase Modules

An Empirical Model of Leakage Current in Poly-silicon TFTs

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An Empirical Model of Leakage Current in Poly-silicon TFTs

2007亚洲显示国际会议

作者： W.J.Wu R.h.Yao Y.F.hu s.h.li Institute of Microelectronics south China University of Technology Guangzhou 510640 China

＜正＞Based on an approximate expression for generation rate,an empirical model for poly-si TFT leakage current is devel- oped in this *** this model,the leakage current is composed of two sections :the leakage current induced by vertical electric field in the overlap region and that induced by lateral electric field in the lateral depleted *** proposed model is analytical without numerical integration,hence attractive for circuit *** addition,it is suitable for po- ly-si TFTs either before or after *** model has been verified by a good agreement between simulated results and experimental data.

关键词： Poly-si TFT Modeling Empirical Model Leakage Current

NUCLEATION AND GROWTh OF ＜111＞ ORIENTATION hOMOEPITAXIAL DIAMOND MONOCRYsTAL

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NUCLEATION AND GROWTH OF ＜111＞ ORIENTATION HOMOEPITAXIAL D...

sixteenth Congress of the International Union of Crystallography

作者： Z.M.Zhang s.h.li Q.Y.Cai h.M.Chen X.C.he D.L.ling s.J.Wang Z.W.hu s.s.Jiang C.Z.Ge N.B.Ming shanghai Jiao Tong Univ. Nanjing Univ.

＜正＞It has been reported that only polycrystal diamond film could be formed on beteroepitaxial substrate by CVD method,which stimulated great interesting to grow homoepitaxial film,however, few reports concerned the growth on ＜111＞ oriented *** this paper,a successful growth of homoepitaxy on（111） natural diamond substrate is presented by using microwave PCVD method. The experimental process was almost same as that of（100） homoepitaxy reported before.

关键词：

AN INVEsTIGATION ON（100）MONOEPITAXIAL DIAMOND MONOCRYsTALliNE FILMs

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AN INVESTIGATION ON（100）MONOEPITAXIAL DIAMOND MONOCRYSTALL...

sixteenth Congress of the International Union of Crystallography

作者： Z.M.Zhang s.h.li Q.Y.Cai h.M.Chen X.C.he D.L.ling s.J.Wang Z.W.Wu s.s.Jiang C.Z.Ge N.B.Ming shanghai Jiao Tong Univ. Nanjing Univ.

＜正＞For diamond’s excellent microelectrical properties and the rapid development of CVD techniques, the diamond high temperature semiconductor materials have been received increasing *** our work,we have obtained quite smooth homoepitaxial monocrystalline films deposited on（100） oriented hT-hP synthesized diamond by microwave PCVD *** microwave frequency was 2.45 Ghz,internal dimension of the quartz horizontal reaction tube was 35mm the reaction gases were acetone and hydrogen,

关键词：

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热轧方形中空截面的残余应力分析

钢结构(中英文) 2009年第6期 83-84页

作者： s.h.li,G.Zeng,Y.F.Ma,Y.J.Guo and X.M.Lai

残余应力对热轧构件的受力性能和强度有很大影响。主要分析了热轧方形中空截面的残余应力。超过600部文献或文章的记载表明,可以使用X射线衍射法分析沿厚度方向的外表面和内表面的残余应力。试验结果对该截面残余应力的量级和分布分析... 详细信息

残余应力对热轧构件的受力性能和强度有很大影响。主要分析了热轧方形中空截面的残余应力。超过600部文献或文章的记载表明,可以使用X射线衍射法分析沿厚度方向的外表面和内表面的残余应力。试验结果对该截面残余应力的量级和分布分析提供了数据。最大的残余应力产生在焊缝上,沿厚度变化的残余应力分布呈现出双线性特性。同时发现,方形截面残余应力的形成过程对其外表面纵向残余应力分布影响很大。

关键词：残余应力热轧 X射线衍射法形成过程

伴门静脉受侵的可切除性肝细胞肝癌术前化疗栓塞有效性和安全性的前瞻性对照研究

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国际医学放射学杂志 2016年第5期 581-582页

作者： Y.F.Zhang R.P.Guo R.h.Zou J.X.shen W.Wei s.h.li 姚绍鑫 Department of hepatobiliary Oncology Cancer CenterSun Yat-sen University

摘要目的评价伴门静静脉受侵的可切除性肝细胞肝癌(hCC)术前肝动脉化学栓塞术(TACE)的预后。方法 2006年2月—2011年7月,320例伴门静脉受侵的可切除性hCC前瞻性非随机性分为2组:直接手术切除组(第1组,205例)直接行手术切除;第2组纳入11... 详细信息

摘要目的评价伴门静静脉受侵的可切除性肝细胞肝癌(hCC)术前肝动脉化学栓塞术(TACE)的预后。方法 2006年2月—2011年7月,320例伴门静脉受侵的可切除性hCC前瞻性非随机性分为2组:直接手术切除组(第1组,205例)直接行手术切除;第2组纳入115例术前TACE组,最终85例随后进行手术切除。结果第1组的1年、3年、5年生

关键词：肝细胞肝癌术前 hCC 可切除性静脉受侵

Intelligent Back Analysis of Displacements Using Precedent Type Analysis For Tunneling

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Intelligent Back Analysis of Displacements Using Precedent T...

中国科学院地质与地球物理研究所2002学术年会

作者： Y.J.shang~a J.G.Cai~b W.D.hao~c X.Y.Wu~c s.h.li~(a,c) a Institute of Geology and Geophysics,Chinese Academy of sciences,P.R.China b Nanyang Technological University,singapore c Beijing Canbao Architectural Design Institute,P.R.China

Based on comprehensive monitored data obtained from typical tunnel projects,and by using engineering experiences of experts together with numerical modeling results,the Precedent Type Analysis(PTA) technique developed was for back-analyzing in situ stress and elastic modulus of rock masses surrounding ***,the PTA is used as a supporting technique in the method of Intelligent Back Analysis(IBA).The IBA method can integrate the mechanism analysis with experimental *** integration is based on ’certainty factors’,and is implemented with the computer program BMP90 with a global inference *** program BMP90 can solve a series of back analysis problems - such as identifying potential problems to be encountered during back analysis,assessing the strategy to be adopted,selecting criteria for back analysis,and ensuring convergence of back analysis *** on the engineering applications to about 100 tunnel projects in China,it is found that the IBA method supported by the PTA technique can be successfully applied to tunnel projects,*** analyzing the lateral in situ stress factor(λ),and the elastic modulus(E) of rock *** method of Intelligent Back Analysis(IBA) supported by Precedent Type Analysis(PTA) and its application to a tunnel project are presented in this paper.

关键词： Tunnel Precedent type analysis Intelligent back analysis of displacements

Constraints on holographic QCD phase transitions from PTA observations

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： song he li li sai Wang shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University school of Physical science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAs Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences school of Fundamental Physics and Mathematical sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) school of Physical sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes