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超短脉冲强激光与固体靶相互作用产生超热电子的能谱研究

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物理学报 2000年第3期49卷 592-596页

作者：陈黎明张杰梁天骄李玉同王龙江文勉中国科学院物理研究所光物理开放研究实验室中国工程物理研究院核物理与化学研究所绵阳621000 中国工程物理研究院核物理与化学研究所

较详尽地描述了能对激光与靶物质相互作用所产生的超热电子进行直接测量的电子磁谱仪的建造及其相应的参量,并利用这台磁谱仪测量了超短脉冲强激光与靶物质相互作用后出射的超热电子的能谱,在5×1015W/cm2.激光强度下,超热电子的最大... 详细信息

较详尽地描述了能对激光与靶物质相互作用所产生的超热电子进行直接测量的电子磁谱仪的建造及其相应的参量,并利用这台磁谱仪测量了超短脉冲强激光与靶物质相互作用后出射的超热电子的能谱,在5×1015W/cm2.激光强度下,超热电子的最大能量大于500keV,能谱结构呈双温Maxwell分布,能谱的峰值出现在50keV附近。

关键词：超短脉冲强激光固体靶相互作用超热电子能谱

Evidence of a two-component jet in the afterglow of GRB 070419A

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Science China(physics,Mechanics & Astronomy) 2010年第S1期53卷 265-266页

作者： ZHENG WeiKang1,2.& DENG JinSong1 1 National Astronomical Observatories,chinese academy of {2.,beijing 100012.China 2.Graduate University of chinese academy of Science,beijing 100049,China National Astronomical Observatories Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Science Beijing China

A two-component jet model is proposed to explain the unusual afterglow of GRB *** the optical light curve,a wide "jet" with an opening angle of >30-40 degrees is assumed to produce the late shallow decay,while the three early power-law segments must be caused by a narrow jet with an opening angle of-2.4 *** energy injections to both components are *** X-ray emission may come from either the wide jet or the narrow *** the latter is correct,the jets may run into an ISM environment and the temporal index of the late energy injection may be q-0.65.

关键词： gamma-rays:bursts gamma-rays:observations

Magneto-optical Enhancement Effect in MnBixAl0.15 Films

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Magneto-optical Enhancement Effect in MnBixAl0.15 Films

Study on Lewis acid promoted condensation of allylalkoxysilanes with (-)-menthyl glyoxylate

1996年中国青年学者物理学讨论会

作者： C.H.Shang Y.J.Wang(institute of physics,{2. academy of sciences,beijing 100080)

A giant polar Kerr rotation is observed in MnBiAl alloy films,when x approaches *** a wavelength of 400nm,e.g.,the average Kerr rotation can be as large as 2.06°.The magneto-optical enhancement is attributed to the formation of a new MnBiAl phase.X-ray diffraction confirms that there still exists unreacted MnBi phase in the samples,which leads to an inhomogeneous distribution of Kerr rotations.A linear correlation between Kerr rotation and reciprocal lattice vector is unraveled for the MnBi (Al)alloy *** finding suggests that the enlarged matrix dements due to the hybridization enhancement between Bi 6p and Mn 3d states are responsible for the observed giant magneto-optical Kerr effect.

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来源： cnki会议评论

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chinese Journal of Chemistry 1994年第5期12卷 440-448页

作者： CHEN, Yong-Jun HUANG, Liang WANG, Dong LI, Ji-Sheng institute of Chemistry, chinese {2. of Science, beijing 100080, China institute of Chemistry Chinese Academy of Science Beijing 100080 China

Allylalkoxydimethylsilanes (2. condense with (-)-menthyl glyoxylate (3) in the presence of Lewis acid to give optically active menthyl 2.hydroxy-4-pentenoate (7) with optical purity of 31-42.. Factors affecting the yi... 详细信息

关键词： Chiral glyoxylate allylalkoxysilane Lewis acid chelation asymmetric reaction.

Micromorphological Features of Diagnostic Horizons in Several soils in Southwest China: Implication for Soil Taxonomic Classification

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Journal of Mountain Science 2010年第1期7卷 73-82页

作者： XU Xiangming HE Yurong HUANG Chengmin XIONG Donghong institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of the chinese academy of sciences Beijing 100049 China Department of Environmental Science and Engineering Sichuan University Chengdu 610065 China

The comparative studies on micromorphological features in diagnostic horizons of Stagnic Anthrosols, Ustic Ferrosols and Ustic Vertosols in southwestern China were conducted to underpin the rationale for chinese Soil Taxonomy. The following findings were explored: (1) Stagnic Anthrosols had the specific micromorphological features, e.g., the humic formation in anthrostagnic epipedon, the platy structures in plow subhorizon, the secondary formation of ferromanganese and the weakly optical-orientation clay domains in hydragric horizon, etc.: (2. The groundmasses of ferric horizon in Ustic Ferrosols appeared in hue of 2.5YR or redder, and had pellicular grain structure; (3) Ustic Vertosols had a crust horizon (Acr), and crack structure dominated in Acr and angular blocky structure in disturbed horizon; (4) Because of the distinct differences in micromorphological features among these three soils, the specific micromorphological features might be employed as diagnostic horizons to differentiate soils while the quantifiable micromorphological features might potentially be selected as diagnostic indices for chinese soil taxonomic classification.

关键词： Soil micromorphology Soil diagnostic horizon chinese Soil Taxonomy Southwestern China

High Power VCSEL Device with Periodic Gain Active Region

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光机电信息 2007年第12期24卷 26-30,35页

作者： NING Yong-qiang1, QIN Li1, SUN Yan-fang1, LI Te1, CUI Jin-jiang1, PENG Biao1, LIU Guang-yu1, ZHANG Yan1, LIU Yun1, WANG Li-jun1, GUI Da-fu2. XU Zu-yan2.(1. Key laboratory of Excited State Processes, Changchun institute of Optics, Fine Mechanics and {2., chinese academy of sciences, Changchun, 130033, China 2. institute of physics, chinese academy of sciences, beijing, 100080, China) Key laboratory of Excited State Processes Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences Changchun 130033 China institute of physics Chinese Academy of Sciences Beijing 100080 China

High power vertical cavity surface emitting lasers(VCSEKLs) with large aperture have been fabricated through improving passivation, lateral oxidation and heat dissipation techniques. Different from conventional three quantum well structures, a periodic gain active region with nine quantum wells was incorporated into the VCSEL structure, with which high efficiency and high power operation were expected. The nine quantum wells were divided into three groups with each of them located at the antinodes of the cavity to enhance the coupling between the optical field and the gain region. Large aperture and bottom-emitting configuration were used to improve the beam quality and the heat dissipation. A maximum output power of 1.4 W was demonstrated at CW operation for a 400 μm-diameter device. The lasing wavelength shifted to 995.5 nm with a FWHM of 2.nm at a current of 4.8 A due to the internal heating and the absence of active water cooling. A ring-shape far field pattern was induced by the non-homogeneous lateral current distribution in large diameter device. The light intensity at the center of the ring increased with increasing current. A symmetric round light spot at the center and single transverse mode operation with a divergence angle of 16° were observed with current beyond 4.8 A.

关键词： VCSEL large aperture high power periodic gain Al2.3

Photosynthetically active radiation retrieval based on HJ-1A/B satellite data

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Science China Earth sciences 2010年第S1期53卷 81-91页

作者： LI Li1,XIN XiaoZhou1,SU GaoLi1,2.& LIU QinHuo1 1 State Key laboratory of Remote Sensing Science,institute of Remote Sensing Applications,{2. academy of sciences,beijing 100101,China 2.Zhejiang Climate Center,Hangzhou 310017,China State Key laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China Zhejiang Climate Center Hangzhou China

Photosynthetically active radiation(PAR) is essential for plant photosynthesis and carbon cycle,and is also important for meteorological and environmental *** advance China's disaster and environmental monitoring capabilities,the HJ-1A/B satellites have been placed in Earth *** of their environmental monitoring objectives is the study of *** simulated direct solar,scattered and environment radiation between 400 and 700 nm under different atmospheric parameters(solar zenith angle,atmospheric water vapor,atmospheric ozone,aerosol optical thickness,surface elevation and surface albedo),and then established a look-up table between these input parameters and *** on the look-up table,we used HJ-1A/B aerosol and surface albedo outputs to derive the corresponding *** of inversed instantaneous and observed PAR values using HJ-1 Heihe experimental data had a root mean square error of 2..2.W m-2.with a relative error of 5.9%.The root mean square error for accumulated daily PAR and observed values was 0.49 MJ m-2.with a relative error of 3.5%.Our approach improved significantly the computational efficiency,compared with using directly radiation transfer *** also studied the sensitivity of various input parameters to photosynthetically active radiation,and found that solar zenith angle and atmospheric aerosols were sensitive PAR *** albedo had some effect on PAR,but water vapor and ozone had minimal impact on PAR.

关键词： Photosynthetically active radiation 6S HJ-1A/B satellites

optical data storage in nonphotosensitive media by femtosecond laser pulses

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Progress in Natural Science:Materials International 2007年第8期17卷 877-880页

作者： Li Yan~(**) Liu Dayong Dou Yanping Yang Hong and Gong Qihuang (State Key laboratory for Mesoscopic physics and Department of physics,Peking University,beijing 100871,China) State Key laboratory for Mesoscopic physics Department of Physics Peking University Beijing 100871 China

Ultrashort lasers have become powerful tools by inducing extremely nonlinear effects in a wide variety of materials. Femtosecond laser data storage in non-photosensitive media is promising for its high density and fast *** reviewed the progress of three types of femtosecond laser storage in transparent materials:three-dimensional bit-oriented storage by micro-voids,holographic data storage by two beam interference and storage by computer-generated holograms.

关键词： femtosecond laser three-dimensional data storage holographic data storage computer-generated hologram

Construction and Physical Properties of a Single Molecular Device

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Construction and Physical Properties of a Single Molecular D...