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厦门大学学报（自然科学版） 2002年第S1期41卷 47-48页

作者： CHEN Fu-rong 1, HUO Li-xing 1, ZHANG Yu-feng 1, ZHANG Li 1, LIU Fang-jun 2. CHEN Gang 2.(1. college of Materials Science and Engineering, Tianjin University, Tianjin 300072. China 2. Aviation Techniques Institute of Beijing, Beijing 10002., China)

To improve the microstructure and properties of the electron beam welded joints, the vacuum or furnace whole post weld heat treatment (FWPWHT) usually should be done on it. The electron beam local post weld heat treatment (EBLPWHT) is a rather new heat treatment procedure that provides the advantages of high precision, flexibility and efficiency, energy saving and higher productivity. In this paper, the microstructure, mechanical properties, fracture toughness and fatigue properties of electron beam welded joints of 30CrMnSiNi2. steel in as-welded (AW) and EBLPWHT conditions have been investigated respectively. The results show that the microstructures of different zones of joints in as-welded condition are changed by EBLPWHT procedure, in which the welds from coarse needle martensite into lath-shaped martensite; the main structures of heat affected zones (HAZ) from lath-shaped martensite into lower bainite. The properties of welded joints can be improved by the EBLPWHT in some extent, especially the fracture toughness of the welds and the fatigue crack resistance of welded joints can be sufficiently improved. However, more appropriate heat treatment parameters of the EBLPWHT have to be studied in order to increase the mechanical properties of base metal near by the HAZ.

关键词： electron beam welding electron beam local heat treatment microstructure fracture toughness fatigue properties

Elimination of undifferentiated cancer cells by pluripotent stem cell inhibitors

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Journal of Molecular Cell Biology 2014年第3期8卷 267-269页

作者： Uri Ben-David1,2.Alva Biran2.Paola Scaffidi3,4,5.Christel Herold-Mende6 Markus Boehringer7 Eran Meshorer2.Nissim Benvenisty1,2 Stem Cell Unit Silberman Institute of Life Sciences The Hebrew University Jerusalem 91904 Israel Department of Genetics Silberman Institute of Life Sciences The Hebrew University Jerusalem 91904 Israel National Cancer Institute NIH Bethesda MD 20892 USA UCL Cancer Institute University College London London WC1E 6BT UK Cancer Research UK London Research Institute London WC2A 3LY UK Division of Neurosurgical Research Department of Neurosurgery University of Heidelberg Heidelberg Germany F. Hoffmann-La Roche AG Basel 4070 Switzerland

Dear Editor, According to the cancer stem cell （CSC） hypothesis, cancer ceils are organized in a hierarchical manner （Reya et al, 2.01）. Indeed, the differentiation state of cancer cells has been linked to their proliferative potential, drug response, and ability to metastasize （Clevers, 2.11）. Targeting self- renewing, undifferentiated cancer ceils could therefore be of importance for the success of cancer therapies. A classical case of a tumor composed of undifferenti- ated and differentiated cells is the tumor induced by pluripotent stem cells （PSCs）（Ben-David and Benvenisty, 2.11）. We have recently identified several small mole- cules termed pluripotent-specific inhibitors （PluriSIns） that selectively target undif- ferentiated tumorigenic PSCs （Ben-David et aL, 2.13）. Several of these compounds, including PluriSIn#1, inhibit the activity of stearoyl-coA desaturase （SCD1）（Ben- David et al, 2.13）. SCD1 is an endoplasmic reticulum （ER）-membrane protein that plays a key role in the biosynthesis of the mono-unsaturated fatty acid oleate. This novel metabolic vulnerability is in line with the unique metabolome described in PSCs （Panopoulos et al, 2.12..

关键词： Pluripotent Stem Cells Hypersensitivity Contact Hypersensitivity cancer cell Circulating Neoplastic Cells

Calcium pretreatment increases thermotolerance of Laminaria japonica sporophytes

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Progress in Natural Science:Materials International 2009年第4期19卷 435-442页

作者： You Wang, Qingyun Yu, Xuexi Tang, Lili Wang college of Marine Life Sciences, Ocean University of China, No. 5.Yushan Road, Qingdao 2.6003, China [a]college of Marine Life Sciences Ocean University of China No. 5 Yushan Road Qingdao 266003 China

Calcium is a secondary messenger in plant signaling, and its concentration changes spatially and temporally during the course of heat stress. In the present study, potassium antimonate was used to visualize calcium localization in blades of a marine macroalga, the juvenile Laminaria japonica sporophytes under heat stress (2.0}°C). Result showed that loosely bound calcium was mainly distributed on the cell wall under normal conditions (10 °C), and flowed into the cytoplasm when exposed to heat. The simutaneous assay on the antioxidant system changes was performed. Oxidative damage, as measured by generation of reactive oxygen species (ROS) malondialdehyde (MDA) content, increased significantly during heat stress, and calcium pretreatment alleviated oxidative damage. The assay on the activities of six antioxidant enzymes demonstrated that their enzymatic activities were inhibited when exposed to heat stress, but Ca2. pretreatment effectively attenuated the inhibition. Results in the present study inferred that calcium homeostasis plays an essential role in L. japonica sporophyte when exposed to heat, and calcium pretreatment could improve its thermo-tolerance.

关键词： Calcium localization Calcium pretreatment Heat stress Antioxidant enzyme Laminaria japonica sporophyte

Density functional theory study of the magnetic properties of rare earth complexes:the magnetic coupling mechanism in Y~Ⅲ and Gd~Ⅲ complexes with nitronyl nitroxide

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Science China Chemistry 2009年第11期52卷 1961-1968页

作者： REN Jie1,2.WANG BingWu1 & CHEN ZhiDa1 1 Beijing National Laboratory for Molecular Sciences,State Key Laboratory of Rare Earth Materials Chemistry and Applications,college of Chemistry and Molecular Engineering,Peking University,Beijing 100871,China 2.college of Science,Hebei University of Science and Technology,Shijiazhuang 0{2.018,China 1. Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China 2. college of Science Hebei University of Science and Technology Shijiazhuang 050018 China

The magnetic coupling interactions of the nitronyl nitroxide radicals bound to diamagnetic(YⅢ) and paramagnetic(GdⅢ) rare earth ions in two model magnetic systems based on novel rare earth organic radical complexes Ln(hfac)3(NITPhOCH3)2.Ln=YⅢ 1,GdⅢ 2.hafc = hexafluoroacetylacetonate;NIT-PhOCH3 = 4'-methoxyo-phenyl-4,4,5.5.tetramethylimidazoline-1-oxyl-3-oxide) have been investigated by density functional theory(DFT).The magnetic coupling mechanisms were also explored from the viewpoint of molecular orbital and spin density *** calculations show that the empty 4d-orbitals of YⅢ and 5.-orbitals of GdⅢ play an important role in the antiferromagnetic coupling between the two nitronyl nitroxide radical ligands,and that the ferromagnetic coupling between the GdⅢ ion and the radical magnetic centers can be attributed to the nearly complete localization of the isotropic 4f-shell and singly occupied magnetic orbital(π) of the nitronyl nitroxide.

关键词： magnetic coupling density functional theory rare earth ion gadolinium(Ⅲ) complexes yttrium(Ⅲ) complexes

Construction and characterization of the transformation-competent artificial chromosome (TAC) libraries of Leymus multicaulis

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Science China(Life Sciences) 2008年第7期51卷 604-613页

作者： XU YueYu 1,2.3,ZHOU YuLei 4,5.,SONG LinLin 6 ,ZHANG Yan 3 &ZHAO MaoLin 1 1 Beijing Agro-Biotechnology Research Center,Beijing Academy of Agriculture and Forestry Science,Beijing 100097,China 2.Department of Chemistry and Chemical Engineering,Hunan Institute of Engineering,Xiangtan 411104,China 3 college of Life Science,Capital Normal University,Beijing 100037,China 4 college of Life Science,Zhongkai University of Agriculture and Technology,Guangzhou 5.02.5.China 5.college of Grassland Science,Gansu Agricultural University,Lanzhou 730070,China 6 Department of Biology,Henan Institute of Science and Technology,Xinxiang 45.003,China 1. Beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Science Beijing 100097 China 2. Department of Chemistry and Chemical Engineering Hunan Institute of Engineering Xiangtan 411104 China 3. college of Life Science Capital Normal University Beijing 100037 China 4. college of Life Science Zhongkai University of Agriculture and Technology Guangzhou 510225 China 5. college of Grassland Science Gansu Agricultural University Lanzhou 730070 China 6. Department of Biology Henan Institute of Science and Technology Xinxiang 453003 China

Transformation-competent artificial chromosome system is able to clone and transfer genes efficiently in *** order to clone genes highly tolerant to barley yellow dwarf virus(BYDV),Aphids,drought and salt from Leymus multicaulis,the two TAC genomic libraries I and II were constructed in vector pYLTAC17 and pYLTAC747H/sacB,which contain about 165.00 and 2.6000 recombinant clones *** genome coverage of the two libraries was totally estimated to be about 3―5.haploid genome equivalents,as size selection of genomic DNA fragments was approximately from 9 to 300 *** of the genomic libraries were collected as bulked pools each containing 5.0 clones or so,stored in twelve 96-deep-well plates and then were gridding in triplicate onto a high-density colony hybridization filter with a 3×3 pattern using a GeneTAC?G3 arraying robot after being transferred manually into three 384-well *** 2.0}1 and 2.90 clones of Library in pYLTAC17 and in pYLTAC747H/sacB were stored individually in fourteen 384-well plates and then were automatically gridding in duplicate onto a high-density colony hybridization filter with a 6×6 pattern after a replication of *** positive clones were detected by using the probe glutahione reductase gene of *** libraries constructed here can be used to isolate genomic clones containing target genes,and to carry out genome walking for positional *** the target TAC clones were isolated,they could be immediately transferred into plant genomes with the Agrobacterium system.

关键词： Leymus multicaulis megabase-size DNA transformation-competent artificial chromosome(TAC) genomic library

The Socialization of Anti-calamity from the View of Relieving Organization's Employing System in the Republic of China——A Case of Central Government Relieving Committee

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学术界 2010年第5期 260-262页

作者： Kong Xiangcheng Liu Fang The Social Science Department of Shanghai Lixin University of commerce The Social Science college ofShanghai University ofEngineering Science

The relief organization of the Republic of China had undergone a great change from traditional mode to socialization of relief *** central government relieving committee(***)was set up for the Jianghuai River Basin flood in *** had made many innovations on the organizing ***,CGRC formed its characteristic with strict standard for the special *** CGRC created a system of risk prevention mechanism by guarantee and supervision from super-ordinate and the *** employing mechanism helped CGRC establish a work team in which each member cooperates,interacts and self-disciplines.

关键词： Jianghuai river flood in 1931 CGRC Employment mechanism Socialization

Influences of low-Ti substitution for La and Mg on the electrochemical and kinetic characteristics of AB_3-type hydrogen storage alloy electrodes

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Science China(Technological Sciences) 2010年第1期53卷 242-247页

作者： DONG ZhenWei1,2.WU YaoMing1,MA LiQun2.SHEN XiaoDong2.& WANG LiMin1 1 State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,C hangchun 13002.,China 2.college of Material Science and Engineering,Nanjing University of Technology,Nanjing 2.0009,China 1. State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The(La0.67Mg0.33)1-xTixNi2.75.o0.2.0}x = 0,0.05.0.10,0.15.and 0.2.,at%) alloys were synthesized by arc melting and subsequent heat solid-liquid diffusing *** structure,electrochemical properties and kinetic characteristics of the alloys were investigated *** results showed that all the alloys mainly consisted of the(La,Mg)Ni3,LaNi5.phases,and the lattice parameters and the cell volumes of the(La,Mg)Ni3 and LaNi5.phases decreased with increasing Ti *** alloy electrodes could be activated to reach their maximum discharge capacity within five *** cycle life after 100 charge/discharge cycles(C100/Cmax) and the high-rate dischargeability at a discharge current density of 12.0 mA/g first increased and then *** the results showed that low-Ti content in AB3-type hydrogen storage alloys was beneficial to improvements of the overall electrochemical properties,and the optimum overall electrochemical performance of the alloy electrodes was obtained when x = 0.05.

关键词： AB3-type alloy metal hydride electrode microstructure electrochemical property kinetic characteristic

Influence of Lactobacillus E1 on the Storage Stability in Emulsion Immobilization

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Journal of Wuhan University of Technology(Materials Science) 2009年第1期24卷 75-80页

作者：孙欣陈西广 college of Life Science Ocean University of China

A coacervation method with double emulsion strategy （w/o/w） was used to prepare immobilized Lactobacillus E1. Diatomite was chosen as the carrier for bacteria. Sodium alginate, dextrin and gelatin were used as protective solutes for the preservation of Lactobacillus E1 and their effects on the storage viability during storage were discussed. The influence of storage temperature on the storage viability was also examined. The results show that high bacteria viable count over 109 cfu/g for an extended shelf life of 37 d can be achieved with 2. sodium alginate, 5. dextrin and 4% gelatin as protective solutes, at 10 ℃ of the storage temperature. This immobilized Lactobacillus E1 has potential use as functional food ingredient for both human dairy food and animal feedstuff.

关键词： lactobacillus microencapsulation storage viability protective solute shelf life

Distinct Pattern of Human Vδ1 γδ T Cells Recognizing MICA

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Cellular & Molecular Immunology 2005年第4期2卷 253-258页

作者： Jianqiang Li~1 Lianxian Cui~1 Wei He~(1,2. ~1Department of Immunology,Institute of Basic Medical Sciences,Chinese Academy of Medical Sciences and School of Basic Medicine,Peking Union Medical college,5.Dong Dan San Tiao,Beijing 100005.China Department of Immunology Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and School of Basic Medicine Peking Union Medical College Beijing 100005 China.

γδT cells represent one unique recognition pattern,the limited recognition,which distinguishes from the specificrecognition for αβT cells and pattern recognition for macrophages.Vδ1 γδT cell is the major subset of human γδT cells,which predominates in mucosal tissue including the intestinal ***,a few antigens thathuman Vδ1TCR can recognize have been *** them,MHC class I chain-related molecules A (MICA)have been studied most *** Vδ1TCR,MICA is also the ligand of NKG2.,a C-type lectin-likeactivating *** human,only Vδ1 cells can simultaneously express both types of receptors of MICAwhile NK cells,αβT cells and other subsets of γδT cells likewise express *** the precisemechanisms are still enigmatic,this distinct pattern of Vδ1 cells recognizing MICA predicts unique biologicalsignificance of Vδ1 cells in immune *** years,some progresses have been made in this *** thisreview we summarize the related reports and put forward some novel views based on our group’s ***& Molecular Immunology.2.05.2.4):2.0}-2.0}.

关键词： Vδ1TCR MICA NKG2. γδ T cell

Spectrofluorimetric determination of artemisinin with pyronine B as the substrate for horseradish peroxidase

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Science Bulletin 2005年第17期 20-24页

作者： CHEN Lihua1, 2. LIU Liuzhan2.& SHEN Hanxi2.1. college of Chemistry, Jishou University, Jishou 416000, China 2. college of Chemistry, Nankai University, Tianjin 300071, China

Enzyme-catalytic fluorescence determination of artemisinin (qinghaosu, QHS) was developed using pyronine B (PB) as substrate of horseradish peroxidase (HRP). The interaction between HRP and QHS was an enzyme-substrate model. The catalytic characteristic of HRP in the oxidation reaction, in which the fluorescence of PB was decreased in the presence of QHS, was studied. The steady-state catalytic rate depended upon enzyme and substrate concentrations, and the Michaelis-Menten parameters Km, Vmax and Kcat were 8.4×10?5.mol · L?1, 7.4×10?6 mol · L?1 s?1 and 5..2. s?1. The catalytic activity of enzyme was inhibited in the presence of deactivated agents and at high temperature, respectively. Under optimum conditions, linear relationship between fluo-rescence intensity change (F0?F) of pyronine B and concen-tration of QHS was in the range of 1.41×10?7―1.2.×10?6 mol · L?1. The detection limit (3σ) was determined to be 2.7×10?8 mol · L?1. The proposed method was applied to the concentration determination of QHS in the media of plasma or urine samples.

关键词： artemisinin (qinghaosu) pyronine B horseradish per-oxidase fluorescence intensity change.