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Measurement of the Coherence of a bose-Einstein Condensate

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Measurement of the Coherence of a Bose-Einstein Condensate

CCAST“激光冷却：玻色—爱因斯坦凝聚和原子激射器”研讨会

作者： E.W.Hagley L.Deng M.kozuma M.Trippenbach Y.B.Band P.S.Julienne k.Helmerson S.L.Rolston W.D.Phillips M.Edwards M.Doery National Institure of Standards and Technology 100 Bureau Drive Stop 8424 GaithersburgMaryland 20899-8424 National Institure of Standards and Technology 100 Bureau Drive Stop 8424GaithersburgMaryland 20899-8424 Departments of Chemistry and Physics.Ben-Gurion University of the Negev Beer-Sheva.Israel 84105 Department of Physics.Ceorgia Southern Universirv Statesboro.Georgia 30460-8031

We present experimental and theorerical studies of the coherence properties of a Bode-Einsteincondensate(BEC)using an interference *** optical standing wave pulses of duration100 ns and separation Δt are applied to a *** standing wave phase grating makes smallcopies of the condensate displaced in momentum *** quantum mechanical amplitudes of eachcopy *** on Δt and on spatial phase variations across the *** find thatthe behavior of a trapped BEC is consistent with a uniform spatial phase.A releared *** large phase variation across the condensate.

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SONIC-新一代快恢复二极管

电气技术 2006年第7期7卷 87-90,81页

作者： S.博斯 L.伊姆列 H.欧斯特曼 P.英格拉姆王培清 IXYS半导体公司拉姆帕泽德国d68623 清华大学电力电子厂

在这篇文章中,介绍了平面型SONIC软恢复二极管的新系列,电压范围从600V到1800V,并有不同的额定电流。采用从硅片背面进行深的磷扩散和控制轴向寿命抑制剂的办法开发出了带有拖尾电流的快恢复及软恢复二极管。被提及的二极管在整个工作... 详细信息

在这篇文章中,介绍了平面型SONIC软恢复二极管的新系列,电压范围从600V到1800V,并有不同的额定电流。采用从硅片背面进行深的磷扩散和控制轴向寿命抑制剂的办法开发出了带有拖尾电流的快恢复及软恢复二极管。被提及的二极管在整个工作温度范围内性能稳定,并且对于温度的变化正向电压降的变化可以忽略不计。SONIC二极管是为高频应用而设计的,在高频应用方面需要稳定的开关特性。文章还比较了SONIC二极管和用铂或金作为寿命抑制剂的标准快恢复外延二极管(FRED)在25℃到125℃下的开关损耗。

关键词： SONIC二极管快恢复二极管软恢复开关损耗

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Generating Solitons by Phase Engineering of a bose-Einstein Condensate

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Generating Solitons by Phase Engineering of a Bose-Einstein ...

CCAST“激光冷却：玻色—爱因斯坦凝聚和原子激射器”研讨会

作者： J.Denschlag J.E.Simsarian D.L.Feder C.W.Clark L.A.Collins J.Cubizolles L.Deng E.W.Hagley k.Helmerson W.P.Reinhardt S.L.Rolston B.I.Schneider W.D.Phillips National Institute of Standards and Technology (NIST.Gaithersburg MD 20899.USA. ~1National Institute of Standards and Technology(NIST.Caithersburg MO 2O899 USA.~2University of Oxford parks Road.OXford OX1 3PU UK. Theoretical Division Mail Stop 3212.Los Alamos Natiooal Laboratory Los AlamosNM 87545USA National Inscitute of Standards and Technology(NIST.Gaithersbure MD 20899.USA. Ecole Normate Superieure 24 rue Lhomond 75231 Paris.France. National Institute of Standards and Technology (NIST.Gaithersburg.MO 20899. USA.Department of Chemistry.University of Washington Seattle.WA 98 95.USA. Physics Division National Science Foundation ArjingtonVA 22230.USA

Quantum phase engineering is demonstrated with two novel techniques thatallow the spatial phase distribution of a bose-Einstein condensate(BEC) to bewritten and read out.A quantum state was designed and produced by opticallyimprinting a phase pattern onto a BEC of sodium atoms,and matter-waveinterferometry with spatially resolved imaging was used to analyze the re-sultant phase *** appropriate phase imprint created *** experimental realization of this nonlinear phenomenon in a BEC Thesubsequent evolution of these excitations was investigated both experimentallyand theoretically.

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A Well-Collimated Quasi-Continuous Atom Laser

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A Well-Collimated Quasi-Continuous Atom Laser

CCAST“激光冷却：玻色—爱因斯坦凝聚和原子激射器”研讨会

作者： E.W.Hagley L.Deng M.kozuma J.Wen k.Helmerson S.L.Rolston W.D.Phillips National Institute of Standards and Technology Gaithersburg.MD 20899.USA. National Institute of Standards and Technology Gaithersburg.MD 20899.USA.Georgia Southern University.Statesboro.CA 30460.USA. Institute of Physics.University of Tokyo Tckyo 153-8902.Japan

Extraction of sodium atoms from a trapped bose-Einstein condensate (BEC) bya coherent. stimulated Raman process is demonstrated. Optical Raman pulsesdrive transitions between trapped and untrapped magnetic sublevels. giving theoutput-coupled BEC fraction a well-defined momentum. The pulsed outputcoupling can be run at such a rate that the extracted atomic wave packetsstrongly overlap, forming a highly directional. quasi-continuous matter wave.

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Temporal,Matter-Wave-Dispersion Talbot Effect

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Temporal,Matter-Wave-Dispersion Talbot Effect

CCAST“激光冷却：玻色—爱因斯坦凝聚和原子激射器”研讨会

作者： L.Deng E.W.Hagley J.Denschlag J.E.Simsarian Mark Edwards C.W.Clark k.Helmerson S.L.Rolston W.D.Phillips National Institute of Standards and Technology Gaithersburg Maryland 20899 Permanent address:Department of Physics Georgia Southern University StatesboroGA 30460

We analyze and experimentally demonstrate a new(temporal)Talbot effect,where a pulsed phasegrating is applied to a cloud of cold atoms(bose-Einstein condensate).In contrast to the usual(spatial)Talbot effect,our atoms gain kinetic energy when diffracted by the pulsed *** energy gain andthe matter-wave-dispersion relation result in an exact(no pxraxial approximation)Talbot effect where theinitial wave front is reconstructed at multiples of a“Talbot tune”*** demonstrate the Talbot effectby applying a second pulsed phase grating after a variable *** this second grating is applied ateven(odd)multiples of r/2,it doubles(cancels)the effect of the first pulsed grating.

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MSCT扫描MPR及SSD三维重建技术对骨盆及髋关节损伤的诊断应用价值

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实用医技杂志 2006年第17期13卷 2960-2962页

作者：陆玉敏卢炳丰马德智黄德尤李清锋黄中包黄昌辉右江民族医学院广西百色533000 广西医科大学第一附属医院广西南宁530021

目的:讨论多层螺旋CT(MSCT)多平面重建(MPR)及表面遮盖(SSD)三维重建技术诊断骨盆及髋关节损伤的临床价值。方法:使用MSCT行骨盆及髋关节损伤42例扫描,重建层厚为1.25mm,间隔1mm,将数据传至工作站,行MPR及SSD重建处理,并对横断面图像及... 详细信息

目的:讨论多层螺旋CT(MSCT)多平面重建(MPR)及表面遮盖(SSD)三维重建技术诊断骨盆及髋关节损伤的临床价值。方法:使用MSCT行骨盆及髋关节损伤42例扫描,重建层厚为1.25mm,间隔1mm,将数据传至工作站,行MPR及SSD重建处理,并对横断面图像及重建图像进行分析。结果:42例骨盆及髋关节损伤患者MPR及SSD图像可清楚显示骨折位置、范围及骨碎片移位情况,SSD能显示三维空间关系,可以从各个方位准确显示表面骨结构的空间改变。结论:多层螺旋CT多平面及SSD三维重建相结合能够清晰立体地显示骨盆、髋关节骨折及脱位的全部细节,对临床制定治疗方案具有重要的参考价值。

关键词：骨盆骨折体层摄影术 X线计算机 MPR SSD 三维重建

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Human immunodeficiency virus type 1 tat accelerates kaposi sarcoma-associated herpesvirus kaposin A-mediated tumorigenesis of transformed fibroblasts in vitro as well as in nude and immunocompetent mice

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南京医科大学学报（自然科学版） 2010年第1期30卷 133-133页

作者： Chen, Xiuying Cheng, Lin Jia, Xuemei Yao, Shuihong Lv, Zhigang Qin, Di Fang, Xin Lu, Chun Nanjing Med Univ, Dept Microbiol & Immunol, Nanjing 210029, Peoples R China.Chen, Xiuying Lu, Chun Nanjing Med Univ, Lab Reprod Med, Nanjing 210029, Peoples R China.Chen, Xiuying Lu, Chun Nanjing Med Univ, key Lab Pathogen Biol Jiangsu Prov, Nanjing 210029, Peoples R China.Chen, Xiuying Lu, Chun key Lab Lab Med Jiangsu Prov, Nanjing 210029, Peoples R China.Chen, Xiuying Lei, Yongliang Lishui Ctr Dis Control & Prevent, Lishui 323000, Zhejiang, Peoples R China.Cheng, Lin Huanghe Sci & Technol Coll, Dept Microbiol & Immunol, Zhengzhou 450006, Peoples R China.Zeng, Yi Youjiang Med Coll Nationalities, Dept Microbiol & Immunol, bose 533000, Peoples R China.

kaposi sarcoma-associated herpesvirus(kSHV) is necessary but not sufficient to cause kaposi sarcoma(kS).Coinfection with human immunodeficiency virus type 1(HIV-1), in the absence of antiretroviral suppressive therapy, drastically increases the risk of ***, we identified that HIV-1 transactivative transcription protein(Tat) was an important cofactor that activated lytic cycle replication of ***, we further investigated the potential of Tat to influence tumorigenesis induced by kSHV kaposin A, a product of kSHV that was encoded by the open reading frame k12(a kSHV-transforming gene).By using colony formation in soft agar, H-3-TdR incorporation, cell cycle, and microarray gene expression analyses, we demonstrated that Tat enhanced proliferation as well as mitogen-activated protein kinase, signal transducer and activator of transcription 3, and phosphatidylinositol 3-kinase/protein kinase B signaling induced by kaposin A in NIH3T3 *** experiments further demonstrated that Tat accelerated tumorigenesis by kaposin A in athymic nu/nu *** obtained from primary tumors of nude mice succeeded inducing tumors in immunocompetent *** data suggest that Tat can accelerate tumorigenesis induced by kaposin *** data present the first line of evidence that Tat may participate in kS pathogenesis by collaborating with kaposin A in acquired immunodeficiency syndrome(AIDS)-related kS(AIDS-kS) *** data also suggest that the model for kaposin and Tat-mediated oncogenesis will contribute to our understanding of the pathogenesis of AIDS-kS at the molecular level and may even be important in exploring a novel therapeutic method for AIDS-kS.

关键词：卡波西肉瘤疱疹病毒肿瘤治疗方法

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