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Build Axial Gradient Field by Using Axial Magnetized Permanent Rings

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Journal of Materials Science & Technology 2002年第6期18卷 483-484页

作者： Quanling PENGInstitute of High Energy Physics, Chinese Academy of Sciences P.O. Box 918-9, beijing 100039, china Chinese Acad Sci Inst High Energy Phys Beijing 100039 Peoples R China

Axial magnetic field produced by an axial magnetized permanent ring was studied. For two permanent rings, if they are magnetized in the same directions, a nearly uniform axial field can be produced. If they are magnetized in opposite direction, an axial gradient magnetic field can be generated, with the field range changing from-Bo to Bo- A permanent magnet with a high axial gradient field was fabricated, the measured results agree with the PANDIRA calculation very well. For wider usage, it is desirable for the field gradient to be changed. Some methods to produce the variable gradient field are presented. These kinds of axial gradient magnetic field can also be used as a beam focusing for linear accelerator if the periodic field can be produced along the beam trajectory. The axial magnetic field is something like a solenoid, large stray field will leak to the outside environment if no method is taken to control them. In this paper, one method is illustrated to shield off the outside leakage field.

关键词： Axial magnetized permanent ring Electron beam Leakage

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2 , XIANG Jianhai 1*, WANG Bing 1,2 , LI Fuhua 1 and TONG Wei 3(1. Experimental Marine Biology Laboratory, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071,china 2. Graduate School of the Chinese Academy of Sciences, beijing 100039, china 3. Genomics & Bioinformatics Institute, Chinese Academy of Sciences, beijing 101300, china) Chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China Chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

Experimental study on phosphorus release from sediments of shallow lake in wave flume

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Science china Earth Sciences 2006年第Z1期49卷 92-101页

作者： SUN Xiaojing,ZHU Guangwei, LUO Liancong & QIN Boqiang Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, china Graduate School of Chinese Academy of Sciences, beijing 100039, china Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing China Graduate School of Chinese Academy of Sciences Beijing China

Influence of wave on sediment resuspension and nutrients release from sediments, collected from Lake Taihu and Lake Chaohu, was studied in flume experiments. Under strong-wave conditions, concentrations of suspended solids (SS), total phosphorus (TP) and dissolved total phosphorus (DTP) in overlying water were increased significantly following the sediments re-suspension. During the experiments on sediments of Lake Taihu and Lake Chaohu, TP concentrations increased 6 times and 3 times, and DTP concentration increased 100% and 70% more than it in presuspension, respectively. Concentration of soluble reactive phosphorus (SRP) of experiment on sediment of Lake Taihu increased 25%. During the massive sediment suspension, the dissolved phosphorus in pore water and much of the phosphorus adsorbed by the sediment particles were released into overlying water. The phenomena in this wave flume experiment are quite similar to the situation observed in situ of Lake Taihu. The critical wave stresses of sediment re-suspension are nearly equal. The change of concentrations of SS, TP, and SRP was the same as that in situ *** study showed that concentrations of TP and SRP in lake water could be increased significantly by wave disturbance. Phosphorus release was significantly enhanced by wave disturbance at the beginning of massive sediment re-suspension, but decreased later.

关键词： shallow lakes, wave disturbance, internal release, phosphorus, wave flume experiment.

Hybrid microsystem with functionalized silicon substrate and PDMS sample operating microchannel: A reconfigurable microfluidics scheme

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Science china(Technological Sciences) 2010年第8期53卷 2272-2277页

作者： LEI YinHua 1 ,XIE Fei 1 ,WANG Wei 1,2 ,WANG HaiBin 3 &LI ZhiHong 1,2 1 Institute of Microelectronics,Peking University,beijing 100871,china 2National Key Laboratory of Science and Technology on Micro/Nano Fabrication,beijing 100871,china 3 No.302 Hospital,beijing 100039,china Institute of Microelectronics Peking University Beijing China National Key Laboratory of Science and Technology on Micro/Nano Fabrication Beijing China No. 302 Hospital Beijing China

A hybrid microsystem with separately functioned temperature controlling substrate and sample operating fluidic microchannel was developed to demonstrate a reconfigurable microfluidics *** temperature controlling substrate integrated a micro heater and a temperature sensor by using traditional silicon-based micromechanical system(MEMS)technique,which guaranteed high performance and robust reliability for repeatable *** sample operating fluidic microchannel was prepared by poly-(dimethylsiloxane) (PDMS)based soft lithography technique,which made it cheap enough for disposable *** PDMS microchannel chip was attached to the temperature controlling substrate for reconfigurable thermal applications.A thin PDMS film was used to seal the microchannel and bridge the functionalized substrate and the sample inside the channel,which facilitated heat transferring and prevented sample contaminating the temperature controlling *** by a one dimensional thermal resistance model,the thin PDMS film was important for the present reconfiguration *** performance of this hybrid microsystem was examined,and the experimental results demonstrated that the chip system could work stably over hours with temperature variation less than *** PDMS microchannel chips were tested on one heating substrate sequentially with a maximum intra-chip temperature difference of *** extracted from serum of a chronic hepatitis B virus(HBV)patient was amplified by this hybrid microsystem and the gel electrophoresis result indicated that the present reconfigurable microfluidic scheme worked successfully.

关键词： reconfigurable microfluidics hybrid microdevice thin PDMS film

Myotoxic activity of a Gln-49 phospholipase A2 from Agkistrodon blomhoffii ussurensis snake venom

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Progress in Natural Science:Materials International 2006年第2期16卷 178-182页

作者： BAO Yongming, BU Pengcheng, YANG Jun, YANG Wei, JIA Peilin and AN Lijia (Department of Bioscience and Biotechnology, Dalian University of Technology, Dalian 116024, china Institute of Biophysics, Chinese Academy of Sciences, beijing 100101, china Graduate School of Chinese Academy of Sciences, beijing 100039, china) Department of Bioscience and Biotechnology Dalian University of Technology Dalian 116024 China Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

A novel myotoxic protein phospholipase A2(PLA2), denoted as Gln49-PLA2, has been isolated from snake venom of Agkistrodon blomhoffii ussurensis, which has weak lethal effect and apparent anticoagulant activity, but lacks the PLA2 and hemorrha-genic activity. Gln49-PLA2 obviously increases of plasma creatine-kinase (CK) upon intramuscular injection in mice, suggesting that it may induce a dose-dependent myonecrosis. Histological studies also reveal morphological changes in mouse skeletal muscles, including extensive myonecrosis, hemorrhage and neutrophil infiltration in the treated animals. The myotoxic ability induced by Gln49-PLA2 can be partially inhibited by heparin.

关键词： snake venom phospholipase A2 Agkistrodon blomhoffii ussurensis myotoxic activity.

Cloning,expression and characterization of a nucleoside diphosphate kinase (NDPK) gene from tobacco

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Progress in Natural Science:Materials International 2007年第8期17卷 906-912页

作者： Zhou Qiyun~(1,2**) Xie Zongming~(1**) Zhang Zhigang~1 Cao Yangrong~1 Zhang jinsong~(1***) Chen Shouyi~(1***) (1.National Key Laboratory of Plant Genomics,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,beijing100101,china 2.Graduate University of Chinese Academy of Sciences,beijing 100039,china) National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Acad. of Sci. Beijing 100101 China Graduate University Chinese Acad. of Sci. Beijing 100039 China

Nucleoside diphosphate kinase (NDPK) is a housekeeping enzyme that maintains the intracellular levels of all (d)NTPs used in biosynthesis except *** we report that a full-length cDNA encoding nucleoside diphosphate kinase (NDPK) was cloned us- ing yeast two-hybrid approach.A tobacco NDPK gene was obtained and designated as ***1 is 704 bp in length and en- codes a putative 16.2 kD protein of 148 amino *** analysis showed that NtNDPK1 is highly homologous to other plant NDPK genes and identified as type I (NDPK1).RNA-gel blot analysis showed that there was no significant difference of NtNDPK1 ex- pression in roots,stems,leaves and *** expression of NtNDPK1 was induced by ABA and PEG and repressed by NaCl,but not significantly affected by Paraquat,wounding and low temperature (4℃) treatments,indicating that NtNDPK1 may play a certain role in response to abiotic *** vitro phosphorylation assay demonstrated that NtNDPK1 had autophosphoryLation activity.

关键词： abiotic stress autophosphorylation activity NtNDPK1 tobacco yeast two-hybrid

Bio-regeneration of p-complexation desulfurization adsorbents

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Science china Chemistry 2005年第6期48卷 538-544页

作者： LI Wangliang1,2, XING Jianmin1, XIONG Xiaochao1,2, SHAN Guobin1,2 & LIU Huizhou1 1. Laboratory of Separation Science and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, beijing 100080, china 2. Graduate School of the Chinese Academy of Sciences,beijing 100039, china Laboratory of Separation Science and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China

The coupling of adsorption desulfurization and biodesulfurization is a new approach to produce clean fuels. Sulfur compounds are firstly adsorbed on adsorbents, and then the ad-sorbents are regenerated by microbial conversion. p-Complexation adsorbent, Cu(I)-Y, was ob-tained by ion exchanging Y-type zeolite with Cu2+ and then by auto-reduction in helium at 450℃ for 3 h. Dibenzothiophene (DBT) was used as a model compound. The effects of cell concentra-tion, volume of oil phase, the ratio of aqueous phase to adsorbent on DBT desorption by a bac-terium were studied. The amounts of DBT desorbed and 2-HBP produced can be apparently increased with addition of n-octane. BDS activity can be improved by increasing cell concentra-tion and the ratio of water-to-adsorbent. 89% of DBT desorbed from the adsorbents can be converted to 2-HBP within 6 h and almost 100% within 24 h, when the volume ratio of oil-to-water was 1/5 mL/mL, the cell concentration was 60 g·L?1, and the ratio of adsorbent-to-oil was 0.03 g·mL?1. The amount of 2-HBP produced was strongly dependent on the volume ratio of oil-to- water, cell concentration and amount of adsorbent. Adsorption capacity of the regenerated ad-sorbent is 95% that of the fresh one after being desorbed with Pseudomonas delafieldii R-8, washed with n-octane, dried at 100℃ for 24 h and auto-reduced in He.

关键词： adsorption desulfurization p-complexation adsorbents bio-regeneration Pseudomonas delafieldii desorption.

Theoretical critical value curve and driving force formation of ecological migration in the arid land

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Chinese Science Bulletin 2006年第A1期51卷 196-203页

作者： ZHU Zi’an & ZHANG Xiaolei Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, china The Graduate School of the Chinese Academy of Sciences, beijing 100039, china Xinjiang Uygur Autonomous Region Development and Reform Commission, Urumqi 830002, china Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China The Graduate School of the Chinese Academy of Sciences Beijing China Xinjiang Uygur Autonomous Region Development and Reform Commission Urumqi China

干旱陆地的易碎的 eco 环境的特征确定它骚乱抵抗的能力更低。在干旱陆地的自然荒芜的绿洲在在宽 Gobi 沙漠散布的马赛克补丁。人口分发是极大地依赖于水资源。人口与驱散的分发，简单生产和生活被描绘风格，和贫穷和遥远。生态的迁居... 详细信息

干旱陆地的易碎的 eco 环境的特征确定它骚乱抵抗的能力更低。在干旱陆地的自然荒芜的绿洲在在宽 Gobi 沙漠散布的马赛克补丁。人口分发是极大地依赖于水资源。人口与驱散的分发，简单生产和生活被描绘风格，和贫穷和遥远。生态的迁居被执行的原因躺在生态的问题。生态的降级是生态的迁居的主要驱动力。然后，驱动力的力量取决于生态的降级的度。因此，是否执行生态的移植取决于生态的降级的程度。理论上，为在干旱陆地的精明的生态的移植的批评的值曲线通过生态学的相对问题的全面研究被提出，经济等等，在干旱陆地与生态的移植经验结合了，并且基于干旱环境的特征。在这篇文章，与这条曲线，理论研究和生态的迁居的一些实践从不做作的行为和生态的移植的驱动力形成的政府行为的观点被做了。它分析活跃驱动力(因素) 和否定力量(因素) ，并且指出预定和在干旱陆地实现生态的迁居的步骤。理论曲线表达某些创见和适用性，它为为实现生态的迁居工程评估生态的降级和理论底的度提供一个量的方法。

关键词：生态迁移临界值驱动力贫瘠地

Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1,3, Shaoxiang XIONG2, Xiulan CHENG1, and Shijun QIAN1* 1Institute of Microbiology, Chinese Academy of Sciences, beijing 100080, china 2Center of Mass Spectrometry, Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china 3Graduate School of the Chinese Academy of Sciences, beijing 100039, china Institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate School of the Chinese Academy of Sciencesbeijing 100039 China Center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 379 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 417 and 459 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.