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冰川冻土 2009年第6期31卷 1178-1185页

作者： LIN Yuan-zhen1,2.GUO Hai3,ZHANG Zhi-yi2.LIN Shan-zhi2.(1. College of Forestry,South china Agricultural university,Guangzhou Guangdong 510642.china 2. Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental Plants,MOE,beijing Forestry university,beijing 100083,china 3. Plant Materials center for Soil and Water Conservation,Ministry of Water Resources,beijing100038,china) College of Forestry South China Agricultural University Guangdong Guangzhou 510642 Plant Materials center for Soil and Water Conservation Ministry of Water ResourcesChina Beijing 100038 beijing Forestry university Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental PlantsMOE Beijing 100083 beijing Forestry university Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental PlantsMOE Beijing 100083

Glucose-6-phosphate dehydrogenase (G6PDH,EC 1.***.1.49) is the first and main regulated enzyme of oxidative pentose phosphate pathway (OPPP),catalyzing the conversion of glucose-6-phosphate to 6-phospho-gluconolactone and playing important roles in the growth and development of plants. It is preciously reported that the enhancement of freezing resistance of Populus suaveolenscuttings is clear related to the distinct increase in cytosolic G6PDH activity. Here,a 1697 bp cDNA fragment (PsG6PDH) is amplified by RT-PCR from cold-induced total RNA of the freezing-tolerant P. suaveolens. A sequence analysis showed that PsG6PDH coding region had 1 530 bp and encoded 510 predicted amino acid residues. Genomic Southern analysis revealed that the isoform is encoded by a few copies of the gene in the poplar genome. The cloned gene PsG6PDHis cloned into binary vector pBI12. and used to transform tobacco. PCR and Southern blotting results verified integration of this gene into the genome of tobacco. Moreover,cold treatment experiments and membrane defense enzymeactivity analysis confirmed that overexpression of the PsG6PDHgene could enhance the tolerance to cold or frigid stresses in transgenic plants.

关键词： Populus suaveolens glucose-6-phosphate dehydrogenase cold resistance gene engineering

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反射式扫描近场光学显微镜及其成像

中国激光 1998年第9期25卷 852-858页

作者：王刚赵钧刘静勇张培林清华大学现代应用物理系和单原子分子测控中心

介绍了一种光纤探针同时作为光源和探测器的反射式扫描近场光学显微镜，该装置通过采用相干探测、偏振分光等技术克服了该类显微镜所普遍面临的噪声背景干扰问题，具有较高的光学信噪比，并通过样品纵向振动调制锁相实现了对样品表面光... 详细信息

介绍了一种光纤探针同时作为光源和探测器的反射式扫描近场光学显微镜，该装置通过采用相干探测、偏振分光等技术克服了该类显微镜所普遍面临的噪声背景干扰问题，具有较高的光学信噪比，并通过样品纵向振动调制锁相实现了对样品表面光强梯度信号的探测成像，进一步改善了成像质量。成像研究表明该装置可对近场衰逝分量进行有效探测并实现了超衍射极限成像。

关键词： SNOM 反射模式衰逝波相干探测光学显微镜

Further research on high-spin structure in ^(161)Lu

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 315-320页

作者： LI YanXia1,2.YU ShaoYing1,2.4,SHEN CaiWan1,5,LI XiaoWei6 & CHEN YongShou3,4 1 School of Science,Huzhou Teachers College,Huzhou 313000,china 2.College of Mathematics,Physics and Information Engineering,Zhejiang Normal university,Jinhua 32.000,china 3 china Institute of atomic Energy,beijing 102.13,china 4 Institute of Theoretical Physics,Chinese Academy of Sciences,beijing 100080,china 5 center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china 6 Department of Physics,Chifeng university,Chifeng 02.001,china School of Science Huzhou Teachers College Huzhou China College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China Department of Physics Chifeng University Chifeng China china Institute of atomic Energy Beijing China

The two-dimensional total routhian surface (TRS) calculations were performed to probe into the triaxial superdeformed characteristics of a strongly populated band X2.in 161Lu. This band was identified as a triaxial superdeformed band by using our TRS method. We also got its formation mechanics,i.e. the neutron-shell correction energy plays a crucial role,while the rotating energy and the deformation-driving effect of high j intruder orbit i13/2.also play an additional role.

关键词： TRS method triaxial superdeformation formation mechanism

Suppression of Decoherence Using Bang-Bang Controls

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Suppression of Decoherence Using Bang-Bang Controls

A submillimeter observation and study of star-forming regions

第2.届中国控制会议

作者： Wang Yanhui,Liu Xiaoshu,Liu Yang,Liu Wenzhang,Long Guilu Key Laboratory For Quantum Information and Measurements and Department of Physics, tsinghua university,beijing {2.P.R. china Key Laboratory for atomic and molecular nanosciences,tsinghua university,beijing {2.P. R. china

＜正＞To suppress the decoherence, in addition to error-correcting codes and the error-avoiding codes, bang-bang control has also been introduced. Here in this work we discuss how to suppress decoherence in quantum systems using bang-bang control,two cases have been discussed,adiabatic decoherence alone,and decoherence with both phase and amplitude damping. We also discussed the different cases when the system is made up of one atom or multi-atom and when such atom with two level or multi-level. It is found that in all the above cases,bang-bang control can suppress decoherence effectively.

关键词： dynamical decoupling adiabatic decoherence nonadiabatic decoherence three level atom BB operations

来源： cnki会议评论

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Chinese Science Bulletin 2002年第1期47卷 16-21页

作者： JIANG Linhua, WU Yuefang & M. MillerDepartment of Astronomy, Peking university, beijing 100871, {2. Chinese Academy of Sciences-Peking university Joint beijing Astrophysics center, beijing 100871, {2. I. Physikalisches Institut, Zulpicher Str Department of Astronomy Peking University Beijing China Chinese Academy of Sciences-Peking university Joint beijing Astrophysics {2. Beijing China I. Physikalisches Institut Koeln 41 Germany

Using the 3-m radio telescope of KOSMA, we mapped 12.O (J = 3-2. lines for three molecular clouds, B35, S146 and TMC-2.. High-velocity molecular outflows are found in all these regions. The physical and dynamical pa-rameters of the outflows are derived, and their shapes and driving sources are analyzed. Contour maps of {2. veloci-ties show that the large scale systematic gradients exist in the three clouds. These observed motions are best explained by rotation after excluding the cause of outflows. Furthermore, in the core region of TMC-2. there is a velocity gradient in opposite direction from that of the large scale. It may be caused by magnetic braking. Finally, angular velocities of the clouds are calculated, and the effects of rotation against gravity and lowering the star-formation rate are also ana-lyzed.

关键词： dynamics of interstellar medium jets and outflows star formation.

Calculation of triaxial superdeformation in ^(174)Hf

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 553-557页

作者： YU ShaoYing1,2.4, LI XiaoWei2. SHEN CaiWan1,5 & CHEN YongShou3,4 1 School of Science, Huzhou Teachers College, Huzhou 313000, china 2.College of Mathematics, Physics and Information Engineering, Zhejiang Normal university, Jinhua 32.000, china 3 china Institute of atomic Energy, beijing 102.13, china 4 Institute of Theoretical Physics, Chinese Academy of Sciences, beijing 100080, china 5 center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, china School of Science Huzhou Teachers College Huzhou China College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China china Institute of atomic Energy Beijing China

A two-dimensional Total Routhian Surface (TRS) calculation with the fixed hexa- decapole deformation ε4 = 0.03 was carried out for several configurations of 174Hf. Results indicate that the shell corrections have an important contribution to the formation of triaxial superdeformation in 174Hf and some possible configuration assignments are made to the 4 TSD bands experimentally found in 174Hf.

关键词： Total Routhian Surface (TRS), triaxial superdeformation, configuration

MORPHOLOGICAL STUDY ON THE ORIENTED CHITOSAN FILM OBTAINED FROM PRE-SHEARED LIQUID CRYSTALLINE SOLUTION IN DICHLOROACETIC ACID

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Chinese Journal of Polymer Science 2001年第4期19卷 385-390页

作者： Zhong-ming Hu Li-heng Wu Da-cheng Wu Shou-xi Chen State Key Laboratory of Polymer Physics and Chemistry, center for molecular Science, Institute of Chemistry Chinese Academy of Sciences, {2. 100080, china china Textile Academy {2. 10002., china Textile College, Sichuan university Chengdu 610065, china 中科院化学所高分子物理与化学国家重点实验室北京中国纺织研究院北京四川大学四川成都

The oriented chitosan films obtained from pre-sheared liquid crystalline chitosan/dichloroacetic acid (DCA) solutions were studied by means of polarized optical microscopy (POM), scanning electron microscopy (SEM), infra-red dichroism technique and wide angle X-ray diffraction (WAXD). The sheer induced band texture in the film was found to correspond to the sinusoidal fibrillar microstructure along the shearing direction on the basis of POM and SEM observations. The sinusoidal fibril was found to be lying within the film plane. The model of chitosan molecular orientation in the pre-sheared film with band texture can be established assuming that the main chain orients in the shearing direction and the side group is perpendicular to the shearing direction. The WAXD azimuthal scanning at 2.theta = 2. degrees indicates that the (002. plane orients perpendicular to the shearing direction.

关键词： chitosan morphology orientation shear induced band texture liquid crystalline solution

Formation mechanisms of heavy oils in the Liaohe Western Depression,Bohai Gulf Basin

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Science china Earth Sciences 2008年第S2期51卷 156-169页

作者： LI SuMei1,2.PANG XiongQi1,2.LIU KeYu3,GAO XianZhi1,2.LI XiaoGuang4,CHEN ZhenYan4 & LIU BaoHong41 State Key Laboratory of Petroleum Resource and Prospecting,china university of Petroleam,{2. 102.49,china 2.Basin and Reservoir Research center,china university of Petroleum,{2. 102.49,china 3 CSIRO Petroleum,P.O. Box 1130,Bentley WA 6102.Australia 4 Liaohe Oilfield Co. Ltd,Petrochina,Panjin 12.010,china State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleam Beijing China Basin and Reservoir Research center China University of Petroleum Beijing China CSIRO Petroleum Bentley Australia Liaohe Oilfield Co. Ltd PetroChina Panjin China

The Liaohe Oilfield in the Liaohe Western Depression of the Bohai Gulf Basin is the third-largest oil producing province and the largest heavy oil producing oilfield in china. A total of 65 oil samples,35 rock samples and 36 reservoir sandstone samples were collected and analyzed utilizing conventional geochemical and biogeochemical approaches to unravel the mechanisms of the formation of the heavy oils. Investigation of the oils with the lowest maturity compared with the oils in the Gaosheng and Niuxintuo oilfields indicates no apparent relation between the maturity and physical properties of the heavy oils. It is suggested that the heavy oil with primary origin is not likely the main mechanism re-sponsible for the majority of the heavy oils in the Liaohe Western Slope. The absence and/or depletion of n-alkanes etc.,with relatively low molecular weight and the occurrence of 2.-norhopane series in the heavy oils as well as the relatively high acidity of the oils all suggest that the majority of the heavy oils once experienced secondary alteration. The fingerprints of the total scanning fluorescence (TSF) of the inner adsorbed hydrocarbons on the reservoir grains and the included hydrocarbons in fluid inclusions are similar to that of the normal oils in the area but are different from the outer adsorbed and reser-voired free oils at present,further indicating that most of the heavy oils are secondary in origin. Analyses of bacteria (microbes) in 7 oil samples indicate that anaerobic and hyperthermophilic Ar-chaeoglobus sp. are the dominant microbes relevant to oil biodegradation,which coincides with the shallow commercial gas reservoirs containing anaerobic bacteria derived gas in the Gaosheng and Leijia teotonic belts. The biodegradation most likely occurs at the water/oil interface,where the forma-tion water is essential for microbe removal and nutrient transportation. We think that biodegradation,water washing and oxidization are interrelated and are the main mech

关键词： heavy oil Liaohe Western Depression biodegradation water washing formation mechanism

Increased exchange rate of histone H1 on chromatin by exogenous myo-genin expression

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Cell Research 2002年第Z2期 395-400页

作者： MING GONG, Ju HUA NI, HONG TI JIADepartment of Biochemistry and molecular Biology, Peking university Health Science {2., beijing 100083, china

To explore the molecular mechanism of chromatin remodeling involved in the regulation of transcriptional activation of specific genes by a myogenic regulatory factor Myogenin, we used NIH3T3 fibroblasts with a stably integrated Hl.l-GFP fusion protein to monitor histone HI movement directly by fluorescence recovery after photobleaching （FRAP） in living cells. The observation from FRAP experiments with myogenin transfected fibroblasts showed that the exchange rate of histone HI in chromatin was obviously increased, indicating that forced expression of exogenous Myogenin can induce chromatin remodeling. The hyper-acetylation of histones H3 and H4 from myogenin transfected fibroblasts was detected by triton-acid-urea （TAU）/SDS （2.D） electrophoresis and Western blot with specific antibodies against acetylated N-termini of histones H3 and H4. RT-PCR analysis indicated that the nAChR β-subunit gene was expressed in the transfected fibroblasts. These results suggest that the expression of exogenous Myogenin ca

关键词： myogenin chromatin remodeling histone acetylation histone HI mobility.