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^(125)Cs的能级结构

原子核物理评论 2004年第4期21卷 331-333页

作者：马英君小松原哲郎王守宇 Cederwall b Nyberg J 张玉虎古野兴平李容俊 Sletten G hagemann G Jensen h Gjorup N 刘运祚吉林大学物理学院吉林长春130023 日本筑波大学串列加速器中心瑞典皇家技术研究所丹麦玻尔研究所串列加速器实验室中国科学院近代物理研究所甘肃兰州730000

通过116Cd(14N,5n),Ebeam=65MeV的核反应布居了125Cs的高自旋态.利用在束γ谱学实验方法,进行了γ γ符合测量,使已知的125Cs核能级纲图得到了扩展,并且修正了某些组态的带头激发能.

关键词：能级结构在束γ谱学 γ-γ符合测量能级纲图高自旋态激发能核反应带头扩展组态

hydrogen Peroxide Alleviates hypoxia during Imbibition and Germination of bean Seeds (<i>Phaseolus vulgaris</i>L.)

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American Journal of Plant Sciences 2014年第24期5卷 3572-3584页

作者： C. b. Rajashekar Kwang-hyun baek Department of horticulture Forestry and Recreation Resources Kansas State University Manhattan KS USA

bean seeds (Phaseolus vulgaris L. cv. Tendergreen) were imbibed in water to examine the effects of hypoxia during imbibition and subsequent germination. hypoxic conditions occurred when seeds were imbibed in water for 24 h or longer and resulted in severe reduction of hypocotyl elongation and stem growth during subsequent germination under non-limiting oxygen conditions. Under continued hypoxic conditions, bean seeds failed to germinate, however, this was reversed in the presence of hydrogen peroxide (20 mM) in the medium. Furthermore, imbibition of seeds in the presence of hydrogen peroxide overcame the adverse hypoxic effects on hypocotyl elongation and stem growth. Exogenous hydrogen peroxide increased the dissolved oxygen levels in the germinating medium, and catalase and transition metal ions such as Fe2+, Cu2+ and Mn2 helped to facilitate the production of oxygen from hydrogen peroxide. In these catalysts, catalase played a major role in the decomposition of hydrogen peroxide as demonstrated by the use of a catalase inhibitor, 3-amino-1, 2, 4-triazole, which reversed the positive effects produced by hydrogen peroxide on germination of seeds under hypoxic conditions. The results show that imbibition is sensitive to oxygen deficits which affect subsequent hypocotyl growth and seedling performance. The adverse effects of hypoxia on germination of bean seeds can be overcome by exogenous hydrogen peroxide.

关键词： Aminotriazole Anoxia Catalase hydrogen Peroxide hypoxia Phaseolus vulgaris Seed Germination

中国五台绿岩带2.52Ga枕状熔岩中候选生物改造结构的生物成因性和同生性评估

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科学通报 2010年第12期55卷 1141-1152页

作者： McLOUGhLIN N FLIEGEL D J FURNES h STAUDIGEL h SIMONETTI A 赵国春 RObINSON P T Department of Earth Science and Center for Geobiology BergenN-5007Norway Scripps Institution of Oceanography University of CaliforniaLa JollaCA 92093-0225USA Department of Earth Sciences University of AlbertaEdmontonT6G 2E3 ABCanada 香港大学地球科学系中国香港 Department of Earth Sciences Dalhousie UniversityHalifaxNova ScotiaB3H 4J1Canada

栖居于海底熔岩基底中的微生物能够侵蚀火山玻璃,形成微米级的孔洞和钻穴.这些生物改造的遗迹被矿化后,即使保存它们的火山玻璃经历了变形和改造成为变质矿物后,矿化的结构也能够保存下来.这些生物改造结构的化石记录所赋存的岩性远远... 详细信息

栖居于海底熔岩基底中的微生物能够侵蚀火山玻璃,形成微米级的孔洞和钻穴.这些生物改造的遗迹被矿化后,即使保存它们的火山玻璃经历了变形和改造成为变质矿物后,矿化的结构也能够保存下来.这些生物改造结构的化石记录所赋存的岩性远远超出了原位洋壳火山玻璃的范围.它们可见于蛇绿岩和前寒武纪绿岩带的变火山玻璃中.本文报道了中国五台山25.2亿年拉斑质枕状熔岩薄片中发现的丝状体型生物显微结构.而且,五台绿岩中发现的微结构在大小、形态和分布上都可以与其他产在太古宙绿片岩相枕状熔岩中的生物蚀变结构相对比.榍石LA-MC-ICP-MSU-Pb原位定年分析给出的年龄是(1.81±0.12)Ga(2σ,n=22,206Pb/238U加权平均).该年龄提供了这些生物蚀变结构矿化的最小年龄,并与区域变质事件年龄相当.这个年龄也代表这些生物蚀变时间的最小年龄估计,从而支持晚太古宙海底生物圈的存在.

关键词：变质火山玻璃微生物改造榍石海底生物圈太古宙华北克拉通

Synthesis and Crystal Structure of 1-D Chain Copper（Ⅱ） Complex: [Cu（L）Cl2]_n （L=2,5-Di-2-pyridyl-1,3,4-oxodiazole）

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Chinese Journal of Structural Chemistry 2004年第2期 141-144+121页

作者： LI Jian-Ronga, b GUO Guo-Conga② bU Xian-heb② hUANG Jin-Shuna a (State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, Fuzhou 350002, China) b (Department of Chemistry, Nankai University, Tianjin 300071, China)

The title complex, [Cu(L)Cl2]n (L = 2,5-di-2-pyridyl-1,3,4-oxodiazole) 1, has been obtained from the reaction of 3,6-di-2-pyridyl-1,2,4,5-tetrazine (bptz) and CuCl2?h2O in a mixture solvent of Ch3CN and Ch2Cl2 (L is generated from the metal-assisted hydrolysis reaction of bptz) and structurally characterized. It crystallizes in space group C2/c of monoclinic system with cell parameters: a = 9.812(2), b = 12.679(3), c = 11.111(2) ? b = 103.92(3)? V = 1341.6(5) 3, Z = 4, Dc = 1.776 g/cm3, Mr = 358.66, F(000) = 716, ?= 2.024 mm1 and S = 1.004. The final R = 0.0346 and wR = 0.0938 for 1011 observed reflections with I > 2(I). The Cu(Ⅱ) ion is six-coordinated by four N atoms of two L ligands and two Cl ions in a distorted octahedral geometry. The ligand L acts as a bis-bidentate ligand to bridge the Cu(Ⅱ) ions, resulting in an infinite chain structure.

关键词： copper(Ⅱ) complex synthesis crystal structure 1-D chain

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ChAMP卫星精确轨道确定

控制工程（北京） 2004年第2期 39-43页

作者： h.Rim Z.Kang P.Nagel S.Yoon S.berradpur b.Schutz b.Tapley 韩冬

ChAMP卫星自2000年7月发射成功以来，已经收集了精确定轨所需的有价值数据。包括black Jack GPS接收机采集的GPS跟踪数据、加速度计数据以及星跟踪器产生的精确姿态数据。2001年2月公布了ChAMP卫星2000年8月7日这一天的飞行数据，到2001... 详细信息

ChAMP卫星自2000年7月发射成功以来，已经收集了精确定轨所需的有价值数据。包括black Jack GPS接收机采集的GPS跟踪数据、加速度计数据以及星跟踪器产生的精确姿态数据。2001年2月公布了ChAMP卫星2000年8月7日这一天的飞行数据，到2001年6月，公布了更多的数据，供国际GPS服务网(IGS)低轨道导航工程参与者使用。本文利用公布的数据集，分析了ChAMP卫星的定轨结果。

关键词： ChAMP卫星星跟踪器姿态数据卫星轨道

Analysis of Wide-bandgap Material OPFET UV Detectors for high Dynamic Range Imaging and Communication Applications

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Communications and Network 2019年第4期11卷 83-117页

作者： Jaya V. Gaitonde Rajesh b. Lohani Department of Electronics and Telecommunication Engineering Goa Engineering College Goa University Government of Goa Ponda India

The ultraviolet (UV) photoresponses of Wurtzite GaN, ZnO, and 6h-SiC-based Optical Field Effect Transistor (OPFET) detectors are estimated with an in-depth analysis of the same considering the generalized model and the front-illuminated model for high resolution imaging and UV communication applications. The gate materials considered for the proposed study are gold (Au) and Indium-Tin-Oxide (ITO) for GaN, Au for SiC, and Au and silver dioxide (AgO2) for ZnO. The results indicate significant improvement in the Linear Dynamic Range (LDR) over the previously investigated GaN OPFET (buried-gate, front-illuminated and generalized) models with Au gate. The generalized model has superior dynamic range than the front-illuminated model. In terms of responsivity, all the models including buried-gate OPFET exhibit high and comparable photoresponses. buried-gate devices on the whole, exhibit faster response than the surface gate models except in the AgO2-ZnO generalized OPFET model wherein the switching time is the lowest. The generalized model enables faster switching than the front-illuminated model. The switching times in all the cases are of the order of nanoseconds to picoseconds. The SiC generalized OPFET model shows the highest 3-db bandwidths of 11.88 Ghz, 36.2 Ghz, and 364 Ghz, and modest unity-gain cut-off frequencies of 4.62 Ghz, 8.71 Ghz, and 5.71 Ghz at the optical power densities of 0.575 μW/cm2, 0.575 mW/cm2, and 0.575 W/cm2 respectively. These are in overall, the highest detection-cum-amplifi-cation bandwidths among all the investigated devices. The same device exhibits the highest LDR of 73.3 db. The device performance is superior to most of the other existing detectors along with comparable LDR, thus, emerging as a high performance photodetector for imaging and communication applications. All the detectors show considerably high detectivities owing to the high responsivity values. The results have been analyzed by the photovoltaic and the photoconductive effec

关键词： UV OPFET GaN SiC ZnO Au ITO AgO2 high Dynamic Range Imaging Photon Counting Communication

纳米填料混合物对低密度聚乙烯基复合材料树老化形态的影响(英文)

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高电压技术 2011年第11期37卷 2739-2745页

作者： Rudi Kurnianto Z.Nawawi h.Ahmad N.hozumi M.Nagao Department of Electrical Engineering Tanjungpura UniversityPontianak-78124Indonesia Faculty of Engineering University Teknologi MalaysiaMalaysia Department of Electrical & Electronic Engineering Aichi Institute of TechnologyJapan Department of Electrical & Electronic Engineering Toyohashi University of TechnologyJapan

This paper deals with a digest on electrical treeing degradation in nanocomposite of magnesium oxide(MgO) added to a low-density polyethylene(LDPE).The objective is to elucidate the"visual"aspects of runaway stage of final treeing breakdown mechanisms,and to ensure that the existence of MgO filler itself is responsible for this aspect instead of voltage application ***"visual"aspect of treeing breakdown was investigated by applying ac ramp voltage with continuous rising speed of 0.5 kV/*** soon as tree had been incepted,the voltage was kept constant to observe the tree propagation until *** tree propagations were also described by their fractal dimension. To ensure the responsibility of MgO filler on the"visual"aspect results,the experiment was repeated using the same rate of ac ramp ***,as soon as tree had been incepted,the voltage was either increased or decreased to a constant value of mean tree inception voltage obtained from the preceding results to observe its propagation to breakdown. As a result,the tree inception voltage was increased with the filler concentration in *** filler is considered not only acted as a physical obstacle for tree to propagate,but also as a chemical obstacle in which the free electron might be trapped to cause difficulties for electron avalanche *** consideration could also be valid for tree propagation up to *** propagation,due to the filler,the tree structure is accompanied by more *** the branches are closely placed each other,the tree tips become relatively uniform field compares to pure *** would produce the higher local breakdown strength at the tree tips,leads to the suppression of ***"visual"aspect of breakdown could be achieved by applying voltage exactly at the inception level. After bridging the tree would not breakdown until a short period of time *** this period,the tree channel will be eroded by internal flashover(IFO) and b

关键词： nano-filler MgO LDPE tree degradation breakdown visual aspect

higher Education on Urban Forestry in Europe: An Overview

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Chinese Forestry Science and Technology 2003年第3期2卷 16-27页

作者： ANDERSEN FRODE KONIJNENDIJK CECIL C RANDRUP ThOMAS b Skov SkovSkov & LandskabDanish Forest and Landscape Research Institute Hφrsholm Kongevej 11DK-2970 HφrsholmDenmark& LandskabDanish Forest and Landscape Research Institute Hφrsholm Kongevej 11DK-2970 HφrsholmDenmark Corresponding author& LandskabDanish Forest and Landscape Research Institute Hφrsholm Kongevej 11.DK-2970 Hφrsholm. Denmark

In order to meet the demands of modern, information-based society, higher education in natural resource management needs to be transformed. Enhanced mobility of students and staff, multi- and transdisciplinary approaches, as well as innovative educational approaches are called for. Moreover, the urban component needs to be better incorporated, as exemplified by the emerging field of urban forestry. This paper relates to the developments in higher education within the context of education on urban forest...

关键词： higher education urban forestry Europe

Induction of Forces at Distance Performed by Piezoelectric Materials

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Journal of Power and Energy Engineering 2018年第1期6卷 33-50页

作者： Elio b. Porcelli Victo S. Filho h4D Scientific Research Laboratory Sao Paulo Brazil

We describe the phenomenon of generation of an external field of forces from piezoelectric materials subjected to the application of electric fields or mechanical stress. We show that piezoelectric materials are capable of producing nonlocal forces of induction in external objects and we conclude that the nature of the forces generated is not originated from traditional interactions. Further we specifically assert that the generation of forces by the piezoelectric materials is ruled by the hypothesis of preexisting condition of generalized quantum entanglement between the molecular structure of the material bulk and the surrounding environment. In addition, the widely spread coupling of the molecules with the environment can be manifested from the so-called direct effect or the converse effect in piezoelectric materials and this coupling is not intermediated by acoustic waves or electromagnetic fields. We show that the novel effect has a theoretical explanation consistent with the generalized quantum entanglement framework and the direction of the induced forces depends on either the direction of the mechanical force or the electric field applied in these materials.

关键词： Piezoelectric Materials Generalized Quantum Entanglement Induction of Forces at Distance Reverse Mode Direct Mode