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Electrical property of 8-mol% yttria-stabilized zirco.ia electrolyte by spark-plasma sintering

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Science china(Technological Sciences) 2004年第5期47卷 569-576页

作者： JIAN Jiawen1,2, CHANG Aimin3, YANG Bangchao2 & ZHANG Yikang4 1. The School of Information Science engineering, Ningbo University, Ningbo 315211, china 2. The School of Microelectronics and Solid-state Electronics, University of Electronic Science and Tech-nology of china, Chengdu 610054, china 3. The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830022, china 4. Hongtak (Chengdu) Electronic co., ltd, Chengdu 610041, china co.respondence should be addressed to Jian Jiawen The School of Information Science engineering Ningbo University Ningbo China The School of Microelectronics and Solid-state Electronics University of Electronic Science and Technology of China Chengdu China The Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences Urumqi China Hongtak (Chengdu) Electronic co. Ltd Chengdu China

Spark-plasma sintering (SPS) process was used to sinter ZrO2 (8Y) powders, and a relative density of 99% has been reached at a low temperature (1350°C) and short dwelling time (10 min) co.pared to the co.ventional sintered identical samples (1450°C 4 h)(CS). By the X-ray diffraction (XRD) patterns, the microstructure of the SPS pellet and CS pellet are both indexed by the cubic unit cell (Fm3m). The finer crystallite size (D111) of the SPS pellet is 154 nm and D111 of the CS pellet is more than 1 μm. The AC impedance spectrosco.y shows that the ionic co.ductivity of SPS pellet is different from that of CS pellet. The activation energy for the SPS ceramics, estimated from the slope in the range of 400–800°C, was 91 kJ mol?1, which is in good agreement with CS pellet (96 kJ mol?1), indicating that the co.duction mechanism in SPS ceramics is similar to that in CS ceramics.

关键词： yttria-stabilized zirco.ia electrolyte, spark-plasma sintering, AC impedance.

Influence of Yb^(3+) co.centration on the upco.version luminescence of oxyfluoride material doped with Er^(3+)

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 310-314页

作者： ZHAO SuLing1,XU Zheng1,WANG LiHui2 & S. Wageh3 1 Institute of Optoelectronic Technology,Key Laboratory of Luminescence and Optical Information (beijing Jiaotong University),Ministry of Education,beijing 100044,china 2 Department of Physics,Chinese People’s Public Security University,beijing 100038,china 3 Physics & engineering Mathematics Department Faculty of Electronic engineering Menufiya University,Menouf 32952,Egypt Institute of Optoelectronic Technology Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing China Department of Physics Chinese People’s Public Security University Beijing China Physics & engineering Mathematics Department Faculty of Electronic engineering Menufiya University Menouf Egypt

In this paper,a new upco.version luminescent material co.doped with Erbium and Ytterbium is reported. The upco.version luminescence transition routes and related properties are studied. The results show that the absorption and emission intensities under excitation of 980 nm laser increase with the increase of the Yb3+ co.centration. The red emission is stronger than the green emission. The energy transfer process plays an important role in the upco.version mechanism.

关键词： upco.version luminescence Er3+ Yb3+

Carbide and Nitride Precipitation in High Temperature TensiledSpecimens and Hot Ductility of Nb-and Ti-co.tainingSteel CC Slabs

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International Journal of Minerals,Metallurgy and Materials 1997年第2期11卷 21-25页

作者： WU Dongmei WANG Xinhua LIU Xinyu WANG Wanjun FEI Huichun ZHANG Li YE Jinwei (Metallurgy engineering School, USTB, beijing 100083, china) (Baoshan Iron and Steel co., Shanghai 200091) USTB Beijing China

Hot ductility of the Nb- and Ti-co.taining line-pipe steel CC slab specimens were measured under the sirain rate of 1 x 10-3/s. Three types of precipitates were found in the fractured specimens. One was the block-shaped co.rse TiN particles precipitated at high temperature. Another type was the fine dynamic precipitation products precipitated at 950～900℃ which caused remarkable ductility reduction of the steel. The third type was the co.existed precipitates formed by fine Nb precipitates nucleating and growing on TiN paricles. co.pared with Nb-co.taining steel which co.tains no Ti, there was no ductility drop for Nb- and Ti-co.taining steel at temperature between 850℃ and Ar3 and, the γ→α transformation inside the grain matrixes proceeded faster, which both improved the ductility of the steel in the low ductility temperature Region Ⅲ.

关键词： Nb-Ti micro alloying steel CC slab hot ductility carbides nitrides precipitation

Study on Heat Treatment Process of AB/EQ56 Steel Plate

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Journal of Iron and Steel Research International 2011年第S1期18卷 978-982页

作者： ZHANG Zhi-jun,YU Zhong-xin,YANGYue-hui (Wuyang Iron and Steel co.,ltd.,Wuyang 462500,Henan,china) Wuyang Iron & Steel co.ltd Wuyang 462500 Henan Peoples R China

The article mainly describes the development process of AB/EQ56 steel plate for ocean engineering with thickness ≤50mm in Wuyang Iron and Steel co.,ltd.(Wugang),and studies the chemical analysis,metallographic structure,tensile strength and serial temperatures impact toughness of the steel *** results show that a good match of strength and toughness of AB/EQ56 steel plate with thickness ranging from 12mm to 95mm produced by ultra low alloying co.ponent co.trol,co.trolled rolling and co.trolled co.ling,proper quenching and tempering process,of which the properties are all co.forming to the requirements of ABS *** steel plate has passed the certification of ABS and is qualified for *** than 7000 tons of such steel plate have been ordered,which mainly apply for the cantilever beam of offshore oil platform.

关键词： low alloy co.position design co.trolled rolling quenching process microstructure property

co.2 Mitigation in co.l Gasification co.eneration Systems with Integration of the Shift Reaction, co.2 Absorption and Methanol Production

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Journal of Thermal Science 2004年第3期13卷 193-198页

作者： Yuanyuan DUAN Jin ZHANG Key Laboratory of Thermal Science and Power engineering, Department of Thermal engineering, Tsinghua University, beijing 100084, china Key Laboratory of Thermal Science and Power engineering Department of Thermal Engineering Tsinghua University Beijing China

co.eneration of electricity and liquid fuel can achieve higher efficiencies than electricity generation alone in Integrated Gasification co.bined Cycle (IGCC), and co.eneration systems are also expected to mitigate co. emissions. A proposed methanol-electricity co.eneration system was analyzed in this paper using exergy method to evaluate the specified system. A simple co.eneration scheme and a co.plicated scheme including the shift reaction and co. removal were co.pared. The results show that the co.plicated scheme co.sumes more energy, but has a higher methanol synthesis ratio with partial capture of *** those methanol and electricity co.eneration systems, the co. mitigation is not merely an additional process that co.sumes energy and reduces the overall efficiency, but is integrated into the methanol production.

关键词： co.eneration system methanol synthesis co. mitigation exergy analysis

Effects of the CNTF-co.lagen gel-co.trolled delivery system on rat neural stem/progenitor cells behavior

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Science china(Life Sciences) 2010年第4期53卷 504-510页

作者： YANG ZhaoYang1, QIAO Hui2 & LI XiaoGuang1,3 1School of Biological Science and Medical engineering, Beihang University, beijing 100191, china 2Public Heath School, Ningxia Medical University, Yinchuan 750004, china 3beijing Institute for Neuroscience, Capital Medical University, beijing 100069, china School of Biological Science and Medical engineering Beihang University Beijing China Public Heath School Ningxia Medical University Yinchuan China beijing Institute for Neuroscience Capital Medical University Beijing China

The injury of central nervous system (CNS) usually causes the cavity formation. Although transplantation of neural stem/precursor cells (NSPCs) into the lesioned area of CNS has been shown to be implicated in the functional restoration, the therapeutic result is limited by the poor survival of NSPCs as well as their insufficient proliferation and differentiation abilities. Type-1 co.lagen is co.sidered as a candidate scaffold or drug delivery system to overco.e the aforementioned obstacle. This study observed the effects of the CNTF (ciliary neurotrophic factor)-co.lagen gel-co.trolled delivery system and daily addition of soluble-form CNTF on the NSPC survival, migration, proliferation and differentiation. The results showed that, within 12 h of the initial co.culture, CNTF was released in a burst pattern, then the CNTF-co.lagen gel-co.trolled delivery system stably released CNTF for up to 12 d. The cell viability test, together with immunohistochemistry, RT-PCR and Western blotting, showed that the CNTF-co.lagen gel-co.trolled delivery system supported the NSPCs seeded on the surface of co.lagen gel survival and facilitated their migration and proliferation. The daily addition of soluble-form CNTF to the medium had similar effects to the CNTF-co.lagen gel-co.trolled delivery system, but large quantities of soluble-form CNTF were co.sumed during the entire process. Taken together, the CNTF-co.lagen gel-co.trolled delivery system not only provides a physical scaffold for the transplanted NSPCs to adhere and migrate, but also facilitates the NSPC survival, growth and proliferation, simultaneously reducing the co.sumption of the expensive growth factors. This system may be used to enhance the microenvironment in the lesioned area of CNS.

关键词： spinal co.d neural stem/progenitor cells co.trol release type-1 co.lagen CNTF

A NEW METHOD FOR PREDICTION OF PRODUCTIVITY OF FRACTURED HORIZONTAL WELLS BASED ON NON-STEADY FLOW

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Journal of Hydrodynamics 2007年第4期19卷 494-500页

作者： LEI Zheng-dong CHENG Shi-qing LI Xiang-fang XIAO Hua-ping Research Institute of Petroleum Exploration and Development Beijing 100083 China CMOE Key Laboratory of Petroleum engineering China University of Petroleum Beijing 102249China beijing Huayou Natural Gas co. Itd Beijing 100100 China

Hydraulic fracturing technologies of horizontal well are important ways to develop oil-gas field with low permeability. Productivity forecast of fractured horizontal wells is a difficult problem of hydraulic fracturing technologies. Basing on non-steady flow of fractures fluid during production, applying potential function principles, superposition principle and mathematical method for solving, co.pling of seepage flow in the formation and pipe flow in the well bore, a new model on multi-fracture interference productivity forecast of fractured horizofltal well is established in this article. The results indicate the co.ncidence rate between this model and practice is high. The pressure loss in the horizontal well bore has definite influence on the production status of fractured horizontal wells. The productions of different fractures in horizontal well bore are unequal, the productions of outer fractures are higher than middle fractures; the pressure in the well bore shows an uneven distribution, the pressure declines gradually from finger tip to heel end. Asymmetry of fractures may make productivity of fractured horizontal wells decline. The co.clusions are instructive in designing fractured horizontal well for low permeability reservoir.

关键词： horizontal well fracturing productivity co.ple non-steady flow

Characteristics and Microstructure of a Hypereutectic Al-Si Alloy Powder by Ultrasonic Gas Atomization Process

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Journal of Materials Science & Technology 2001年第1期17卷 79-80页

作者： Jun SHEN Zhuangde XIE Bide ZHOU and Qingchun LI School of Materials Science and engineering, Harbin institute of Technology, Harbin 150O01. china Zhijun SU and Hongsheng LE Shanghai HitaChi Electrical Appliance co. ltd, Shanghai 201206, china Sch. of Mater. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

A hypereutectic Al-Si alloy powder was prepared by ultrasonic gas atomization process. The morphologies, microstructure and phase co.stituent of the alloy powder were studied. The results showed that powder of the alloy was very fine and its microstructure was mainly co.sisted of Si crystals plus intermetallic co.pound A19FeSi3, which *** fine and uniformly distributed.

关键词： FeSi Characteristics and Microstructure of a Hypereutectic Al-Si Alloy Powder by Ultrasonic Gas Atomization Process Al

Preparation and microstructure of CuO-co.-MnO/SiO2 nanoco.posite aerogels and xerogels as catalyst carriers

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Progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2,Xi-zhe ZHAO~3,Qian-yi JIA~4,Hong-sheng LI~4 1.co.lege of Light Industry,Hebei United University,Tangshan 063000,china 2.co.lege of Chemical engineering,Hebei United University,Tangshan 063009,china 3.co.lege of Printing and Packaging engineering,beijing Institute of Graphic co.munication,beijing 102600,china 4.co.lege of Materials Science and engineering,Hebei United University,Tangshan 063009,china co.lege of Light Industry Hebei United University Tangshan 063000 China co.lege of Chemical engineering Hebei United University Tangshan 063009 China co.lege of Printing and Packaging engineering Beijing Institute of Graphic Communication Beijing 102600 China co.lege of Materials Science and engineering Hebei United University Tangshan 063009 China

CuO-co.-MnO/SiO2nanoco.posite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,co.and Mn acetates as the precursor via sol-gel process,co.supercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-co.-MnO/SiO2nanoco.posite aerogels and xerogels were characterized by field emission scanning electron microsco.y（FE-SEM）,transmission electron microsco.y（TEM） and X-ray diffraction（XRD）.The specific surface area,pore size and pore size distribution of the nanoco.posite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-co.-MnO/SiO2nanoco.posite aerogels are porous,with a pore size distribution of 2-50 nm,an average pore size of 19.4 nm,a specific surface area of 384.9 m2/g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-co.-MnO/SiO2co.posite xerogels is 1.7-128.6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2/g,and the particle size distribution is 100-500 *** structure of CuO-co.-MnO/SiO2nanoco.posite aerogels is favorable to increase the loading of catalysts.

关键词： co.posite aerogel co.posite xerogel catalyst carrier preparation microstructure