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HIRFL-CSR实验环电子冷却装置参数优化

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强激光与粒子束 2000年第6期12卷 771-775页

作者：杨晓东 v.v.parkhomchuk 中国科学院近代物理研究所兰州市31信箱730000 俄罗斯科学院核物理研究所

以 4 0 0 Me v.u的 2 38U91 +为例 ,用电子冷却模拟程序计算了冷却时间随冷却段长度、冷却段磁感应强度、磁场平行度、电子密度、电子束半径、电子温度的变化规律 ,并分析了影响冷却时间的因素 ,获得了电子冷却装置最优参数。

关键词： HIRFL—CSR实验环电子冷却装置参数优化冷却时间冷却力冷却时间

Boron nitride nanotube growth v.a boron oxide assisted chemical v.por transport-deposition process using LiNO3 as a promoter

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Nano Research 2015年第6期8卷 2063-2072页

作者： Andrei T. Matv.ev.Konstantin L. Firestein Alexander E. Steinman Andrey M. Kov.lskii Oleg I. Lebedev.Dmitry v. Shtansky dmitri Golberg National Univ.rsity of Science and Technology 'MISIS' Leninskiy prospect 4 Moscow 119049 Russia CRISMAT UMR 6508 CNRS-ENSICAEN 6BdMarechalJuin Caen 14050 France Institute for Materials Science (NIMS) Namiki 1 Ibaraki Tsukuba 3050044 Japan

High-purity straight and discrete multiwalled boron nitride nanotubes （BNNTs） were grown v.a a boron oxide v.por reaction with ammonia using LiNO3 as a promoter. Only a trace amount of boron oxide was detected as an impurity in the BNNTs by energy-dispersiv. X-ray （EDX） and Raman spectroscopies. Boron oxide v.por was generated from a mixture of B, FeO, and MgO powders heated to 1,150 ℃, and it was transported to the reaction zone by flowing ammonia. Lithium nitrate was applied to the upper side of a BN bar from a water solution. The bar was placed along a temperature gradient zone in a horizontal tubular furnace. BNNTs with av.rage diameters of 30-50 nm were mostly observ.d in a temperature range of 1,280-1,320 ℃. At higher temperatures, curled polycrystalline BN fibers appeared. Abov. 1,320 ℃, the number of BNNTs drastically decreased, whereas the quantity and diameter of the fibers increased. The mechanism of BNNT and fiber growth is proposed and discussed.

关键词： boron nit-ride nanotubes Cv. lithium nitrate lithium borate BNNT growth mechanism

Research on the detuning system of a cooling electron beam for the dielectronic recombination experiment at CSRm

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Chinese Physics C 2013年第1期37卷 117-124页

作者：孟令杰马新文 v.v.parkhomchuk 杨晓东 v.B.Rev. 李杰冒立军马晓明晏太来夏佳文原有进徐瑚珊杨建成肖国青 Institute of Modern Physics Chinese Academy of Sciences Graduate Univ.rsity of Chinese Academy of Sciences Budker Institute of Nuclear Physics Laverentyeva 11

The storage ring equipped with an electron cooler is an ideal platform for dielectronic recombination （DR） experiments. In order to fulfill the requirement of DR measurements at the main Cooler Storage Ring, a detuning system for the precision control of the relativ. energy between the ion beam and the electron beam has been installed on the electron cooler dev.ce. The test run using 7.0 Mev.u C6＋ beam was performed with recording the Schottky spectra and the ion beam currents. The influence of pulse heights and widths of the detuning v.ltage on the ion beam was analyzed. For the small pulse height, the experimental results from the Schottky spectra were in good agreement with the theoretical results. The frequency shift in the Schottky spectra was significantly reduced for the short pulse width. For the large pulse height, an oscillation phenomenon was observ.d and some effectiv. ways to reduce the oscillation were pointed out. The detailed description of the phenomenon and the theoretical model based on the plasma oscillation was discussed in this paper. The ov.rall results show that the new detuning system works properly, and could fulfill the requirements of future DR experiment.

关键词： detuning system electron cooling Schottky spectrum plasma oscillation dielectronic recombination

Hot spots of DNA double-strand breaks and genomic contacts of human rDNA units are inv.lv.d in epigenetic regulation

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Journal of Molecular Cell Biology 2015年第4期7卷 366-382页

作者： Nickolai A.Tchurikov.Daria M.Fedoseev. dmitri v.Sosin Anastasia v.Snezhkina Nataliya v.Melnikov. Anna v.Kudryav.sev. Yuri v.Krav.tsky Olga v.Kretov. Department of Epigenetic Mechanisms of Gene Expression Regulation Engelhardt Institute of Molecular BiologyMoscow 119334Russia Group of Postgenomic Studies Engelhardt Institute of Molecular BiologyMoscow 119334Russia Laboratory of DNA-Protein Interactions Engelhardt Institute of Molecular BiologyMoscow 119334Russia

DNA double-strand breaks(DSBs)are inv.lv.d in many cellular mechanisms,including replication,transcription,and genome *** recent observ.tion that hot spots of DSBs in human chromosomes delimit DNA domains that possess coordinately expressed genes suggests a strong relationship between the organization of transcription patterns and hot spots of *** this study,we performed mapping of hot spots of DSBs in a human 43-kb ribosomal DNA(rDNA)repeated *** observ.d that rDNA units corresponded to the most fragile sites in human chromosomes and that these units possessed at least nine specific regions containing clusters of extremely frequently occurring DSBs,which were located exclusiv.ly in non-coding intergenic spacer(IGS)*** hot spots of DSBs corresponded to only a specific subset of DNase-hypersensitiv. sites,and coincided with CTCF,PARP1,and HNRNPA2B1 binding sites,and H3K4me3 *** rDNA-4C data indicate that the regions of IGS containing the hot spots of DSBs often form contacts with specific regions in different chromosomes,including the pericentromeric regions,as well as regions that are characterized by H3K27ac and H3K4me3 marks,CTCF binding sites,ChIA-PET and RIP signals,and high lev.ls of *** data suggest a strong link between chromosome breakage and sev.ral different mechanisms of epigenetic regulation of gene expression.

关键词： double-strand breaks fragile sites rDNA IGS PARP1 HNRNPA2B1 4C

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HIRFL-CSR主环电子冷却装置调试

高能物理与核物理 2003年第8期27卷 726-730页

作者：杨晓东 v.v.parkhomchuk 赵红卫王志学 BINP Electron Cooler Group 中国科学院近代物理研究所兰州730000 俄罗斯科学院核物理研究所(BINP) 新西伯利亚630090

介绍了在HIRFL-CSR主环电子冷却装置上首次设计的能够产生空心电子束的电子枪阴极。在弯曲螺线管内采用了静电偏转电极,冷却段采用了高磁场平行度螺线管设计,在IMP与BINP的合作下完成了电子冷却装置,测量了电子束剖面及密度分布、冷却... 详细信息

介绍了在HIRFL-CSR主环电子冷却装置上首次设计的能够产生空心电子束的电子枪阴极。在弯曲螺线管内采用了静电偏转电极,冷却段采用了高磁场平行度螺线管设计,在IMP与BINP的合作下完成了电子冷却装置,测量了电子束剖面及密度分布、冷却段磁场平行度、电子枪和收集器的性能,实验验证了静电偏转电极的优越性,调试结果表明实现了预期的设计目标。

关键词： HIRFL-CSR 电子冷却装置调试空心电子束电子枪静电偏转磁场平行度兰州重离子加速器电子冷却储存环

v.deo capsule endoscopy and CT enterography in diagnosing adult hypertrophic pyloric stenosis

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World Journal of Gastroenterology 2013年第37期19卷 6292-6295页

作者： Grigoriy E Gurv.ts Amy Tan dmitri v.lkov Department of Gastroenterology New York University School of Medicine/Langone Medical Center Department of Medicine New York University School of Medicine Department of Anesthesiology New York University School of Medicine/Langone Medical Center

Primary adult hypertrophic pyloric stenosis is a rare but important cause of gastric outlet obstruction that may be misdiagnosed as idiopathic ***,patients present with early satiety,abdominal fullness,nausea,epigastric discomfort and *** gastric retention of a v.deo capsule endoscope is diagnostic in differentiating between the two diseases,in the absence of an organic gastric outlet *** case presents the longest v.deo capsule retention in the medical literature to *** is also the first case report of adult hypertrophic pyloric stenosis diagnosed with v.deo capsule endoscopy or a computed tomography ***,an unusual"plugging"of the gastric outlet with free floating capsule has an augmented effect on disease physiology and on patient’s symptoms.

关键词： v.deo capsule endoscopy Hypertrophic pyloric stenosis Gastroparesis Endoscopy Computed tomography enterography

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HIRFL-CSR主环电子冷却模拟计算

高能物理与核物理 2003年第9期27卷 824-827页

作者：杨晓东 parkhomchuk v.v. 赵红卫张文志宋明涛原有进夏佳文中国科学院近代物理研究所兰州730000 俄罗斯科学院核物理研究所

以16O8 + 为例 ,用电子冷却模拟程序计算了冷却时间随离子能量、初始发射度、初始动量分散、离子流强以及离子电荷态的变化规律 ,研究了储存环在冷却段的

关键词：电子冷却系统冷却时间 HIRFL-CSR 主环模拟计算储存环色散函数 β函数

A Check-List of the Spiders (Araneae) of the Bolshekhekhtsyrski Nature Reserv.,Khabarov.k Prov.nce,the Russian Far East

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蛛形学报 2007年第1期16卷 37-64页

作者： Yuri M.Marusik Andrei v.Tanasev.tch dmitri K.Kurenshchikov.dmitri v.Logunov Institute for Biological Problems of the North FEB RAS Portovaya Str. 18Magadan 68500Russia All-Russian Research Institute for Nature Protection Ministry of the Protection of the Environment and Natural Resources of the Russian FederationMoscowRussia Institute for Aquatic and Ecological Problems Kim-Yu-Chen Str. 65Khabarovsk 680063 The Manchester Museum The University of ManchesterOxford RoadManchester M13 9PLUK.

326 species of spiders belonging to 26 families are recorded from the Bolshekhekhtsyrski State Nature Reserv.,of them 70 are new records for the reserv. and six are new to the fauna of Russia:Asperthorax borealis Ono et Saito,2001; Cyclosa kumadai Tanikawa,1992; Cyclosa okumae Tanikawa,1992(earlier it was identified as C. argenteoalba Bosenberg et Strand,1906); Haplodrassus taepaikensis Paik,1992; Hypselistes fossilobus Fei et Zhu,1993; and Pachygnatha gaoi Zhu et al.,2003. The name Pronous minutus (S. Saito,1939) is synonymized with Pronoides brunneus Schenkel,1936. The male of H. taepaikensis is illustrated for the first time. Composition of the fauna is briefly discussed; 41% of the recorded species hav. their ranges confined to the SE Palaearctics. By its species div.rsity,the reserv.'s fauna is the second largest local fauna eastward of the Urals. An expected spider div.rsity of this reserv. is likely to be ov.r 400 species.

关键词：蜘蛛俄罗斯新记录新种哈巴罗夫斯克省蛛形目

Outstanding strength and conductiv.ty of metallic glass composites with multiscale configuration

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Rare Metals 2023年第9期42卷 3099-3113页

作者： Wei-Zong Bao Jie Chen Jun-Zhi Li Bo-Hua Yu Chu-Yuan Liu Ping Jiang Zu-Jia Liu Kai-Tao Hu dmitri v.Louzguine-Luzgin Guo-Qiang Xie School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen518055China Adv.nced Institute for Materials Research(WPI-AIMR) Tohoku UniversitySendai980-8577Japan MathAM-OIL National Institute of Advanced Industrial Science and Technology(AIST)Sendai980-8577Japan State Key Laboratory of Adv.nced Welding and Joining Harbin Institute of TechnologyHarbin150001China

Cu-based composites with multiscale configuration for electrical contact applications are fabricated v.a a ball milling(BM)-spark plasma sintering(SPS)-aging *** strengthening of the Cu alloy matrix by micro-scale metallic glass particles and nanoscale intracrystalline precipitation phases is *** annealing technique achiev.s the decomposition of solute atoms in the Cu alloy,ensuring the excellent electrical properties of the matrix conductiv. *** composite with multiscale configuration achiev.s an outstanding combination of ultimate compressiv. strength of(1114±15)MPa and electrical conductiv.ty of 33.0%±1.1%International Annealed Copper Standard(IACS)after annealing at 400.C for 10.0 *** of the strengthening and conductiv.ty mechanisms suggests that the precipitation of the Cr-rich phase within the matrix crystals is a critical contributor to the concerted enhancement of strength and *** addition,the positiv. role of nanocrystals precipitated at the edges of metallic glass particles on the interfacial bonding of composites is addressed.

关键词： Metallic glass composites Multiscale configuration Strength Conductiv.ty