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Could bright γ-ray burst optical transients have been recorded historically?

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Research in Astronomy and Astrophysics 2012年第3期12卷 260-268页

作者： Richard G. Strom Fu-Yuan Zhao Cheng-Min Zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Netherlands Institute for Radio Astronomy （ASTRON） EO. Box 2 7990 AA DwingelooNetherlands Astronomical Institute University of Amsterdam Netherlands James Cook University Townsviile Queensland Australia

The brightest optical flash from a γ-ray burst （GRB） was, briefly, a naked- eye object. Several other GRBs have produced optical transients only slightly fainter. We argue that, based upon the recently accumulated data from hundreds of GRB transients, many such optical events should have been visible to the unaided eye in the course of human history. The most likely repositories of such observations are histor- ical records from the Orient, and we have located and discuss a number of candidates. We also consider the value of such observations, should any very likely ones be uncovered, to modern astrophysics.

关键词： γ-rays: bursts—optical transients—historical records

Polypeptide Brushes Grown via Surface-initiated Ring-opening Polymerization of α-Amino Acid N-Carboxyanhydrides

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chinese Journal of Polymer Science 2015年第7期33卷 931-931,932-946页

作者： Yong Shen 李志波 Harm-Anton Klok Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences School of Polymer Science and Engineering Qingdao University of Science and Technology cole Polytechnique Fédérale de Lausanne (EPFL) Institut des Matériaux and Institut des Sciences et Ingénierie Chimiques Laboratoire des Polymères Batiment MXD Station 12 CH-1015 Lausanne Switzerland

Polypeptide brushes are attractive platforms to generate functional and responsive interfaces that are of potential interest due to their possible biodegradability, biocompatibility and tunable secondary structures. Surface-initiated ringopening polymerization（SI-ROP） of α-amino acid N-carboxyanhydrides represents a powerful and versatile strategy to generate polypeptide brushes. This review is an attempt to capture the state-of-the-art in this field and highlights the latest developments in several selected areas. In addition to presenting an overview of the synthetic methods that have been used to generate polypeptide brushes via SI-ROP, this article will discuss the preparation of patterned polypeptide brushes, the conformational properties of surface-tethered polypeptides, ways to control chain orientation at surfaces as well as properties and applications of these thin polymer films.

关键词： Polypeptide brushes Surface α-Amino acid N-carboxyanhydrides Ring-opening polymerization Secondary structure

Geofluids Hosted in the Deep Crust: From Systematics to Parametrization of their Significance

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Acta Geologica Sinica(English Edition) 2021年第S1期95卷 31-33页

作者： Giovanni MARTINELLI INGV Istituto Nazionale di Geofisica e Vulcanologia Department of PalermoPalermoItaly Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhouChina Key Laboratory of Petroleum Resources Gansu Province/Key Laboratory of Petroleum Resources ResearchInstitute of Geology and GeophysicsChinese Academy of SciencesLanzhouChina

Earthquake is a sudden release of energy due to fault *** severity of the damages can be minimized by development of a culture of prevention which includes the Seismic Hazard Assessment,microzonation studies and appro... 详细信息

关键词： probabilistic seismic hazard assessment deterministic seismic hazard assessment helium isotopes geochemical prospection earthquake precursors

Cultivable Microfungal Communities Inhabiting Biological Soil Crusts in the Tengger Desert, China

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Pedosphere 2015年第3期25卷 351-363页

作者： Isabella GRISHKAN JIA Rong-Liang Giora J.KIDRON LI Xin-Rong Institute of Evolution University of Haifa Shapotou Desert Research and Experiment Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Institute of Earth sciences The Hebrew University of JerusalemGivat Ram Campus

Biological soil crusts are essential components of arid ecosystems. We examined the variations in microfungal communities inhabiting different biological crust types in the vicinity of the Shapotou Research Station in the Tengger Desert, China. A total of 134 species from 66 genera were isolated using the soil dilution plate method. The mycobiota of the crusts from the Tengger Desert, similar to that of the Negev Desert in Israel, was dominated by melanin-containing species with large multicellular spores. Abundance of these xeric species increased spatially with increasing xeric conditions from moss-dominated to cyanobacterial crusts. Density of microfungal isolates displayed the opposite trend and was positively correlated with chlorophyll content, indicating the possible significant influence of organic matter content and wetness duration on fungal biomass. Within a chronosequence of the localities of different periods after sand stabilization with revegetation, little variations were revealed in species composition and isolate density of the crust microfungal communities, while a tendency towards a decrease in the community diversity level with the crust age was noted Microfungal communities from stabilized localities differed from those of the natural localities in abundance of the dominant and some frequent species, and in the fluctuations of diversity characteristics between the cyanobacterial and moss-dominated crusts. The variations in mycobiotie parameters in the soil crusts of the Tengger Desert were apparently associated with the topographically induced variations in abiotic conditions, while the differences in microfungal community of soil crusts between the Tengger and Negev deserts, such as the significantly higher abundance of thermotolerant species in the crusts of the Tengger Deserts, were caused by the principal differences in their precipitation regimes, associated with different rainy seasons, winter and summer in the Negev and Tengger deserts,

关键词： chlorophyll content community structure fungal diversity precipitation regimes revegetation sand stabilization wetness duration

Finite Groups of Spencer Height ≤ 3

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Algebra Colloquium 2015年第3期22卷 437-444页

作者： Wenbin Guo Dina P. Andreeva Alexander N. Skiba School of Mathematical sciencesUniversity of Science and Technology of China Hefei 230026 China Department of Mathematics Francisk Skorina Gomel State University Gomel 246019 Belarus

In this paper, we describe the finite groups G in which every maximal chain M3 〈 M2 〈 M1 〈 M0 = G contains a proper subnormal subgroup of G.

关键词： finite group subnormal subgroup maximal chain Spencer height Schmidt group

Natural Heritage Value of Xinjiang Tianshan and Global Comparative Analysis

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Journal of Mountain Science 2012年第2期9卷 262-273页

作者： XU Xiaoliang YANG Zhaoping Adayi Saiken Shao Rui LIU Xinyu Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011XinjiangChina Graduate University of the chinese academy of sciences Beijing 100049China

Xinjiang Tianshan is a serial natural property that has been nominated for World Heritage *** paper presents a systematically comprehensive and comparative analysis of the heritage resources of Xinjiang Tianshan according to the World Heritage *** biological,ecological and aesthetic values,which are of global importance, are *** is concluded that Xinjiang Tianshan meets the world heritage criteria(vii)and (ix).Xinjiang Tianshan is compared with other mountain world heritage sites,mountains in Central Asia,the Tianshan Mountains outside China,and with the protected areas of the Tianshan Mountains on the Tentative List for World Heritage Sites,so as to provide objective data for the world heritage application.

关键词： Xinjiang Tianshan Natural Heritage Heritage characteristics Heritage values Comparative analysis

Anode and Cathode Spots in High-Voltage Nanosecond-Pulse Discharge Initiated by Runaway Electrons in Air

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chinese Physics Letters 2014年第8期31卷 92-95页

作者：邵涛 VictorF.Tarasenko 杨文晋 DmitryV.Beloplotov 章程 MikhailI.Lomaev 严萍 DmitryA.Sorokin InstituteofElectricalEngineering ChineseAcademyofSciencesBeijing100190 KeyLaboratoryofPowerElectronicsandElectricDrive ChineseAcademyofSciencesBeijing100190 InstituteofHighCurrentElectronics RussianAcademyofSciencesTomsk634055Russia NationalResearchTomskStateUniversity Tomsk634055Russia

We report the experimental results with nanosecond-pulse discharges formed in the air gap between a fiat electrode and a sharp electrode. The appearance of anode and cathode spots on the electrodes is studied experimentally. It is considered that bright spots on the fiat cathode with positive polarity of the sharp electrode are formed due to the explosive electron emission on the cathode and the dynamic displacement current in the gap. It is also shown that with negative polarity of the sharp electrode, bright spots on the flat anode are formed after changing the polarity of the flat electrode due to the discharge oscillatory mode. Under these conditions, the explosive electron emission firstly forms on the sharp cathode. With negative polarity of the sharp electrode of the subnanosecond-pulse pulser, the runaway electron beam current is measured behind the anode foil with a time resolution of no more than 100ps.

关键词： Cathodes

A Similitude Method and the Corresponding Blade Design of a Low-Speed Large-Scale Axial Compressor Rotor

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Journal of Thermal Science 2014年第2期23卷 145-152页

作者： YU Chenghai MA Ning WANG Kai DU Juan Van den Braembussche R.A. LIN Feng Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of Sciences Graduate School of chinese academy of sciences von Karman Institute for Fluid Dynamics Turbomachinery and Propulsion DepartmentWaterloose steenweg721640 Sint-Genesius-RodeBelgium

A similitude method to model the tip clearance flow in a high-speed compressor with a low-speed model is presented in this *** first step of this method is the derivation of similarity criteria for tip clearance flow,on the basis of an inviscid model of tip clearance *** aerodynamic parameters needed for the model design are then obtained from a numerical simulation of the target high-speed compressor *** to the aerodynamic and geometric parameters of the target compressor rotor,a large-scale low-speed rotor blade is designed with an inverse blade design *** order to validate the similitude method,the features of tip clearance flow in the low-speed model compressor are compared with the ones in the high-speed compressor at both design and small flow rate *** is found that not only the trajectory of the tip leakage vortex but also the interface between the tip leakage flow and the incoming main flow in the high-speed compressor match well with that of its low speed *** results validate the effectiveness of the similitude method for the tip clearance flow proposed in this paper.

关键词： Similitude method Low-speed model Tip clearance flow TLF/MF interface

An Image Skeletonization-Based Tool for Pollen Tube Morphology Analysis and Phenotyping

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Journal of Integrative Plant Biology 2013年第2期55卷 131-141页

作者： Chaofeng Wang Cai-Pinq Gui Hai-Kuan Liu Dong Zhang Axel Mosig CAS-MPG Partner InStitute and CAS'Key Laboratory for Computational BiolOgy Shanghai Institutes for Biological Sciences The ChineseAcademy of Sciences Shanghai 200031 China National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for BiologicalSciences The Chinese Academy of Sciences Shanghai 200032 China Department of Biology and Biotechnology Ruhr University Bochum Bochum 44801 Germany

The mechanism underlying pollen tube growth involves diverse genes and molecular pathways. Alterations in the regulatory genes or pathways cause phenotypic changes reflected by cellular morphology, which can be captured using fluorescence microscopy. Determining and classifying pollen tube morphological phenotypes in such microscopic images is key to our understanding the involvement of genes and pathways. In this context, we propose a computational method to extract quantitative morphological features, and demonstrate that these features reflect morphological differences relevant to distinguish different defects of pollen tube growth. The corresponding software tool furthermore includes a novel semi-automated image segmentation approach, allowing to highly accurately identify the boundary of a pollen tube in a microscopic image.

关键词： Cell morphology image skeletonization pollen tube growth branching image based phenotyping.