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Superplastic deformation of commercial OOCr2.Ni5Mo3N0.17 duplex stainless steel

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Journal of university of Science and Technology beijing 2003年第2期10卷 49-55页

作者： Peixue Zhang, Xueping Ren, and Jianxin XieMaterials Science and Engineering School, university of Science and Technology beijing, beijing 100083, china

The superplastic behavior of a commercial duplex stainless steel has beenstudied by means of isothermal hot tensile test at temperatures of 850-1050 deg C for the initialstrain rates ranging from 3X10^(-4) s^(-1) to 5X10^(-2. s^(-1). At 960 deg C, the best superplasticdeformation that caused the maximum elongation greater than 840 percent was obtained for an initialstrain rate of 1.2.10^(-3) s^(-1). At 850 deg C, the best elongation 500 percent was achieved for aninitial strain rate of 2.5X10^(-3) s^(-1) During the deformation in higher temperature region,coarse gamma grains formed during the prior treatments were broken into spherical particles,resulting in a homogeneous dispersion of gamma particles within the delta-ferrite matrix. However,at lower temperatures between 800 and 950 deg C, the sigma phase was formed through the eutectoiddecomposition of delta->gamma+sigma, resulting finally in the stable equiaxed micro-duplexstructures with delta/gamma and gamma/sigma respectively. The precipitation of the sigma phaseplayed an important role in improving the superplasticity at 850 deg C. The strain-rate sensitivitycoefficient, m-values, were also determined by the strain rate change tests. The microstructurestudies show that the superplastic process occurs mainly by the local work hardening and thesubsequent dynamic recrystallization and a grain boundary sliding and grain switching mechanism.

关键词： duplex stainless steel superplasticity strain-rate sensitivitycoefficient isothermal hot tensile test

A Novel Network Management Model Based on XML for Service and Resource

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计算机工程 2002年第S1期28卷 77-81页

作者： ZHANG JinxiangWU JianpingWANG Jilong(Network Research Center of Tsinghua university, beijing 100084,{2., jxzhang@***) Network Research Center of Tsinghua university Beijing 100084China j xzhang ***

XML can allow for the interchange of data between management applications using different information models. Furthermore, CORBA technique is increasingly used in the management of service and resource in the heterogeneous network environment. As the scheme of information arrangement of CORBA is flat file style, which handles querying, deleting, and insertinginformation inefficiently, this paper puts forward a novel network management model based on XML in the domain of the management of CERNET (china Education and Research Network), which has used a tree structure of managed objects arrangement to provide efficient operation on managed objects. In addition, arrangement, definition, implementation and finding schemes for CORBA managed objects using XML are also given by the tree structure, and thus can arrange and retrieve managed objects efficiently.

关键词： XMLCORBANetwork managementModel

A variational iteration method for studying the ENSO mechanism

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Progress in Natural Science:Materials International 2004年第12期 94-96页

作者： MO Jiaqi 1*, LIN Wantao 2.and ZHU Jiang 2.1. Anhui Normal university, Wuhu 2.1000, china 2. Institute of Atmospheric Physics, Chinese Academy of Sciences,{2. 10002., china) AnhuiNormaluniversity Wuhu241000China InstituteofAtmosphericPhysics ChineseAcademyofSciencesBeijing100029China

A coupled system of the El Nio/La Nio Southern Oscillation (ENSO) mechanism is studied. Using the variational iteration theory, the approximations of the solution of an ENSO model is obtained.

关键词： ENSO模型大气物理学耦合系统变分迭代非线性

Granulocyte-macrophage colony-stimulating factor DNA prime-protein boost strategy to enhance efficacy of a recombinant pertussis DNA vac-cine

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Acta Pharmacologica Sinica 2006年第11期27卷 1487-1494页

作者： Qing-tian LI~(2.3,5)Yong-zhang ZHU~(2.3,5)Jia-you CHU~(2.6)Ke DONG~3 Ping HE~3 Chun-yan FENG~3 Bao-yu HU~3 Shu-min ZHANG~4 Xiao-kui GUO~(3,6)2.Institute of Medical Biology,Peking Union Medical College and Chinese Academy of Medical Sciences,Kunming 650118,china 3 Department of Medical Microbiology and Parasitology,Shanghai Jiao Tong university School of Medicine,Shanghai 2.002.,china 4 Chinese National Institute for the Control of Pharmaceutical and Biological Products,beijing 100050,china InstituteofMedicalBiology PekingUnionMedicalCollegeandChineseAcademyofMedicalSciencesKunming650118China DepartmentofMedicalMicrobiologyandParasitology ShanghaiJiaoTongUniversitySchoolofMedicineShanghai200025China

Aim:To investigate a new strategy to enhance the efficacy of a recombinantpertussis DNA *** strategy is co-injection with cytokine plasmids asprime,and boosted with purified homologous ***:A recombinantpertussis DNA vaccine containing the pertussis toxin subunit 1(PTS 1),fragmentsof the filamentous hemagglutinin(FHA)gene and pertactin(PRN)gene encodingfilamentous hemagglutinin and pertactin were ***/c mice were im-munized with several DNA vaccines and antigen-specific antibodies anti-PTS1,anti-PRN,anti-FHA,cytokines interleukin(IL)-10,IL-4,IFN-γ,TNF-α,and spleno-cyte-proliferation assay were used to describe immune ***:Therecombinant DNA vaccine could elicit similar immune responses in mice as that ofseparate plasmids encoding the 3 fragments,*** immunized withDNA and boosted with the corresponding protein elicited more antibodies thanthose that received DNA as *** particular,when the mice were co-immu-nized with murine granulocyte-macrophage colony-stimulating factor plasmidsand boosted with proteins,all 4 cytokines and the 3 antigen-specific antibodieswere significantly increased compared to the pVAX1 ***-PTS1,anti-FHA,IL-4 and TNF-α elicited in the colony stimulating factor(CSF)prime-proteinboost group showed significant increase compared to all the other ***:This prime and boost strategy has proven to be very useful in im-proving the immunogenicity of DNA vaccines against pertussis.

关键词： granulocyte-macrophage colony-stimulating factor pertussis DNA vaccines

NONLINEAR DYNAMIC INVERSION CONTROL WITH ADAPTIVE COMPENSATION FOR FLIGHT CONTROL SYSTEM

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Chinese Journal of Aeronautics 1997年第3期10卷 68-73页

作者： Xu Jun, Zhang Minglian, Li Youliang (Department of Automatic Control, beijing university of Aeronautics and Astronautics, beijing, 100083, china)

A type of nonlinear dynamic inversion control with adaptive compensation is proposed in order to overcome its over sensitivity to parameter uncertainty and disturbance for flight control system using nonlinear dynamic inversion. This control strategy is different from the general strategy of a nonlinear adaptive control by taking into consideration both parameter uncertainty and external disturbance, the two major uncertain forms in flight control. Finally, an analysis of the stabilily of this control structure is given.

关键词： adaptive control flight control systems nonlinear dynamic inversion

Cytoskeleton reorganization and FAK phosphorylation are involved in lanthanum(Ⅲ)-promoted proliferation and differentiation in rat osteoblasts

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Progress in Natural Science:Materials International 2009年第3期19卷 331-335页

作者： Xi Wang,Jian Huang*,Tianlan Zhang*,Kui Wang Department of Chemical Biology,Peking university School of Pharmaceutical Sciences,38 Xueyuan Road,beijing 100083,{2. [a]Department of Chemical Biology Peking University School of Pharmaceutical Sciences 38 Xueyuan Road Beijing 100083 China

The effect of lanthanum ion(La 3+ )on osteoblast function and cytoskeleton is assessed in *** were isolated from Sprague- Dawley fetal neonatal *** proliferation and gene expression levels of cbfa-1,alkaline phosphatase(ALP),osteocalcin(OC),bone sialo- protein(BSP)and osteopontin(OPN)were examined by cell counting and *** F-actin was stained with rhodamine-con- jugated phalloidin and was visualized by a confocal *** the results,10à 8-10 à4M La 3+-induced osteoblast proliferation on day 2. Data from the RT-PCR assay revealed that 10à 6M La 3+up-regulated the expression levels of ALP,BSP,and cbfa-1 on day 4,while it enhanced the expressions of OC and OPN on day *** F-actin cytoskeleton was strengthened and reorganized under the exposure of La3 +.In addition, the phosphorylation of focal adhesion kinase(FAK)was significantly promoted in 2. h evaluated by Western blot *** findings indi- cate that La3 +promotes osteoblast activity through the phosphorylation of FAK and reorganization of the cytoskeleton.

关键词： La3 + Osteoblasts Proliferation Differentiation Cytoskeleton FAK phosphorylation

Screening of Highly Effective Sinorhizobium meliloti Strains for 'Vector' Alfalfa and Testing of Its Competitive Nodulation Ability in the Field

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Pedosphere 2007年第2期17卷 219-228页

作者： ZENG Zhao-Hai CHEN Wen-Xin HU Yue-Gao SUI Xin-Hua CHEN Dan-Ming College of Agronomy and Biotechnology China Agricultural University Beijing 100094 （China） College of Biology/Key Laboratory of Agro-Microbial Resource and Application Ministry of Agriculture China Agricultural University Beijing 100094 （China）

Seventeen Sinorhizobium meliloti strains from seven provinces in china were used to screen highly effective strains for alfalfa cultivar in a greenhouse study and their symbiotic relationship and competitive ability were studied in the field. CCBAU30138 was the most effective strain, as evidenced by increase in dry weights. A field experiment showed that the inoculation of alfalfa with CCBAU30138 resulted in increases of 11.9% and 19.6% of dry matter production and crude protein production, respectively, in forage of monocultured plants. The total dry matter yields of alfalfa and tall fescue in binary culture were increased by 16.3% by inoculation of alfalfa with this strain. These results showed that S. rneliloti strain CCBAU30138 was an effective inoculant both in the greenhouse and in the field. The analysis of randomly amplified polymorphic DNA （RAPD） by polymerase chain reaction （PCR） from nodule extracts showed that the strain CCBAU30138 had high competitiveness in the field. It occupied 47.5% of nodules in alfalfa monoculture and 44.4% of nodules in alfalfa-tall fescue binary culture after 2. weeks of growth. In conclusion, a simple system to select highly effective and competitive symbiotic strains specific to alfalfa was established. Using this system, a *** suitable for the alfalfa cultivar ‘Vector＇ grown in Wuqiao County of Hebei Province was obtained.

关键词： alfalfa inoculant selection Sinorhizobium meliloti tall fescue

Study on SGDC Electrolyte Film Prepared by RF Magnetron Sputtering

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稀有金属材料与工程 2006年第S3期 501-503页

作者： Cong Wang~1 Lihai Xu~(1,2. Weihua Tang~2.(1.Center of Condensed Matter Physics and Material Physics,School of Science,Beihang university,beijing 100083,{2.) (2.Department of Physics,Center for Optoelectronics Materials and Devices,Zhejiang Sci-Tech university,Xiasha College Park,Hangzhou 310018,{2.)

Sm and Gd co-doped Ceria (SGDC:Sm0.1Gd0.1Ce0.8O1.90) films as the electrolytes were investigated for the IT-SOFCs （intermediate-temperature solid oxide fuel cells）.SGDC sensing films were successfully prepared on the Al2.3substrates by RF-magnetron *** relationship between sputtering parameters and film microstructure was discussed, and the optimum parameters were *** crystal structure analysis and surface morphologic observation of the SGDC films were carried out through X-ray diffraction （XRD） and scanning electron microscopy （SEM）.The oxygen ion conductivity of the SGDC film was evaluated by AC impedance spectroscopy at the different *** XRD analysis shows that the SGDC films grow preferentially along the （111） compact *** crystallinity of the SGDC films is enhanced with the increase of the RF sputtering power from 150 W to 2.0 *** oxygen ion conductivity of the SGDC was measured at the temperature from 600℃to 800℃in air by AC impedance *** result shows that a high oxygen ion conductivity of 2.44×***-1was achieved at 800℃.

关键词： solid oxide fuel cell electrolyte film Sm0.1Gd0.1Ce0.8O1.90 RF magnetron sputtering

Preparation of High-Surface-Area SnO2.and ZrO2.by Reflux-Digestion and Solvothermal Methods

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稀有金属材料与工程 2006年第S3期 634-637页

作者： Ji-Ying Wei~1 Feng Jiang~1 Gang Xu~1 Sheng-Ming Xu~(1,2. (1.Institute of Nuclear and New Energy Technology,Tsinghua university,beijing 100084,{2.) (2.State Key Laboratory of Chemo/Biosensing and Chemometrics,Hunan university,Changsha 410082.{2.)

The influence of the preparation methods on the properties of SnO2.nd ZrO2.owders,especially the specific surface area and the stability upon calcination was ***2.nd ZrO2.repared by chemical precipitation using reflux-digestion process with NaOH possess high surface area at the calcination temperature of 500℃～1000℃.A novel solvothermal process in the presence of urea was used to synthesize nanocrystalline SnO2.owders excluding the adulteration of *** increasing the concentration of urea,the grain size of the as-prepared powders reduced and the surface area increased. SnO2.anocrystals with a grain size of ca.1 nm and a high surface area of 331 m2.-1were obtained by this *** high-surface-area powders are favorable for gas-sensing and catalysis applications,and the development of an advanced material for structural engineering ceramics.

关键词： tin dioxide zirconia reflux-digestion solvothermal high-surface-area