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Computation of Magnetic Anomalies and Gradients for Spatial Arbitrary Posture Regular Body

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Journal of Earth Science 2009年第6期20卷 995-1002页

作者：洪东明姚长利郑元满郭伟骆遥 Key Laboratory of geo-detection (China University of geosciences Beijing)Ministry of Education Beijing 100083 China School of geophysics and Information Technology China University of GeosciencesBeijing Key Laboratory of geo-detection (China University of geosciences Beijing) Ministry of Education Beijing 100083 China China Aero geophysical Survey and Remote Sensing Center for Land and Resources

In the interaction computation for 3D gravity and magnetic anomalies due to arbitrarily shaped homogenous magnetized polyhedron model composed of triangular facets, there are many difficult points, such as mass computing, absence of a mature computer technique in 3D geological body modeling, inconvenient human-computer interaction, hard program coding, etc.. Based on the formulae of the magnetic field due to horizontal regular bodies, and by applying forward theory with the three-dimensional Cartesian coordinate system transformation, the forward problems of magnetic anomalies and gradient tensors for arbitrary slantwise regular bodies were solved. It is shown that the magnetic calculating expressions of the arbitrary posture regular body are corrected by comparing results with the homogeneous polyhedral body model outcome data. Furthermore, in the same condition, the former significantly reduced forward time. Applying a new forward method of regular body expressions in arbitrary posture, developed software for interaction computation between the 3D geological body model and magnetic field has advantages of fast calculation speed, easy manipulation, etc..

关键词： regular magnetic body spatial posture coordinate system transformation transformation matrix forward calculation.

Paleovegetational and paleoclimatic evolution series on northeastern Qinghai-Xizang Plateau in the last 30 ka

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Science China Earth Sciences 1996年第6期39卷 640-649页

作者：王富葆阎革Department of geo-Ocean Sciences Nanjing University Nanjing 210008 China) 韩辉友Department of geo-Ocean Sciences Nanjing University Nanjing 210008 China) 曹琼英Department of geo-Ocean Sciences Nanjing University Nanjing 210008 China) 周卫健Department of geo-Ocean Sciences Nanjing University Nanjing 210008 China) 李升峰Department of geo-Ocean Sciences Nanjing University Nanjing 210008 China) Department of geo-Ocean Sciences Nanjing University Nanjing 210008 China)

Palynological study of 2 lacustrine suites by limnological and 14C dating reveals the local evolutionary history of the paleovegetation and the paleoclimate of Zoige Plateau, northeastern Qinghai-Xizang Plateau, since the last 30ka. The territorial paleovegetation evolution experienced 7 stages: alpine desert vegetation, grassland, marsh and sub-alpine meadow, islet forest, marsh and meadow, Picea and Abies forest, marsh and sub-alpine meadow, islet dark conifer, marsh and sub-alpine meadow, and the inferred paleoclimate evolution shared similar variations correspondingly. The major climatic events during the periods of post-glacial and the Holocene left their distinct marks in sediment record.

关键词： Zoige Plateau paleovegetation paleoclimate topsoil pollen distribution.

Radiation-Induced Synthesis of Polyvinylpyrrolidone （PVP） Nanogels

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Journal of Physical Science and Application 2016年第5期6卷 21-26页

作者： Adrian Alejandro ges Naranjo HerlysViltres Cobas Danaydis Fonseca Rogdriguez Manuel Rapado Paneque Yuri Aguilera Corrales Higher Institute of Technologies and Applied Science Nuclear Development and Technological Applications Centre La Habana Cuba Center of Research in Applied Science and Technology Advanced Legaria-Unit Polytechnic National Institute Ciudad de Mexico Mexico Finlay Institute La Habana Cuba Center for Technological Applications and Nuclear Development La Habana Cuba

Nanogels-particles of polymer gels having the dimensions in the order of nanometers-are gaining attention for their wide application as biomaterials. Mainly, the nanogels are promising novel pharmaceutical carriers for small biologically active agents, bin macromolecules and can be chemically modified to incorporate various ligands for targeted drug delivery. This important factor has stimulated research on dissimilar science field such as nanotechnology and biotechnology, polymer and materials sciences, biochemistry, radiation chemistry and pharmaceutical sciences. A multitude of techniques have been described for the synthesis of this nanomaterial from polymers. However, the use of ionizing radiation （γ, e-） has demonstrated to be especially suitable for obtaining polymeric nanogels with a high degree of purity for biomedical applications, although the gamma radiation has not been widely utilized for these purposes. The aim of this paper is to develop the synthesis of PVP （polyvynilpyrrolidone） nanogels by gamma irradiation, for their evaluation as potential pharmaceutical carriers. Experiments were performed using argon saturated solution of PVP （0.1-1%）. Crosstinking reactions were carried out in a gamma irradiation chamber with a 60Co source （ISOGAMMA LLCo）, at room temperature. The PVP concentration influence was evaluated in PVP solutions （0.1% and 0.25%） at 15 kGy. The SEM （scanning electron microscopy）, ATR （attenuate total reflection spectroscopy）, DLS （dynamic light scattering）, and viscosimetry were used as characterization techniques.

关键词： Polyvynilpyrrolidon nanogels, gamma irradiation, biomaterial.

Wide area real time kinematic decimetre positioning with multiple carrier GNSS signals

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Science China Earth Sciences 2010年第5期53卷 731-740页

作者： FENG YanMing1 & LI BoFeng1,2 1 Faculty of Science and Technology, Queensland University of Technology, GPO Box 2434, QLD 4001, Australia 2 Department of Surveying and geo-informatics Engineering, Tongji University, Shanghai 200092, China Faculty of Science and Technology Queensland University of Technology Queensland Australia Department of Surveying and geo-informatics Engineering Tongji University Shanghai China

This paper presents the technical basis for wide area real time decimetre positioning services using multiple carrier signals transmitted by future GNSS such as modernized GPS and Compass systems. The first step is to form two ionosphere-reduced extra-widelanes (EWL) that have the minimal total noise levels in cycles, considering the effects of the ionospheric and tropospheric delays, orbital error, and phase noise terms in various observational environments. The proposed three carrier ambiguity resolution approach can determine the integer ambiguities of the selected EWL signals with geometry-free and geometry- based estimations respectively over the distances of typically hundreds of kilometres. With two ambiguity-fixed EWL signals, the kinematic positioning solutions can be achieved in decimetre level accuracy. A semi-simulation method is employed to generate three frequency Compass data to demonstrate the above expected performance for decimetre positioning services. Both theoretical and experimental results have demonstrated the overall 3D root mean square accuracy of better than 15 cm obtained through with a phase smoothing process over 120 epochs. The dominating error factor in this positioning result is the residual tropospheric biases, which would become less correlated as the baselines grow beyond hundreds of kilometres. With respect to dual-frequency based precise point positioning and wide area differential positioning solutions, a major advantage of using the third frequency signals is the convergence time being shorten from tens of minutes to a few minutes. In addition, due to the instant ambiguity resolution capability, phase breaks or cycle slips no longer affect the continuity of the solutions. This reliable decimetre positioning capability introduces a significant improvement to safety-of-life, liability-critical and professional applications.

关键词： GNSS three carrier ambiguity resolution real time kinematic decimetre positioning

A new iguanodontid (Jin-zhousaurus yangi *** ***.) from the Yixian Formation of western Liaoning,China

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Chinese Science Bulletin 2001年第19期46卷 1669-1672页

作者： WANG Xiaolin & XU Xing1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China 2. College of Earth Sciences and Resources, China University of geo-sciences, Beijing 100083, China Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China College of Earth Sciences and Resources China University of Geosciences Beijing China

A new iguanodontid, Jinzhousaurus yangi gen. et sp. nov., is erected based on the cranial and dental morphology of a specimen from the Yixian Formation of western Liaoning. Although a few primitive characteristics remain, Jinzhousaurus yangi display a number of characteristics similar to those seen in derived iguanodontids. Other interesting characteristics include the absence of antorbital fenestra and the frontal excluded from the participation in orbit, which are closer to the condition in hadrosaurids. The unusual combination of the characteristics provides important data for assessing morphological evolution toward hadrosaurs. The new discovery also represents the first reported large-sized dinosaur from Jehol fauna in western Liaoning, and increases the diversity of this famous fauna. Furthermore, the discovery of a derived iguanodontid from the Yixian Formation provides further evidence supporting a Cretaceous age of the Jehol fauna, which is consistent with an isotopic age.

关键词： Western Liaoning Lower Cretaceous Yixian Formation Jehol Biota Iguanodontid

Hemipelagic Deposition of the Silurian Kepingtage Formation in Tarim Basin and Its Sedimentologic Significance

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Journal of Earth Science 2009年第6期20卷 921-931页

作者：姜在兴王玥魏垂高 College of Energy China University of GeosciencesBeijing College of geo-resource and Information China University of PetroleumDongying

Hemipelagic contourites were interpreted in the Silurian Kepingtage （柯坪塔格） Formation in the Tarim basin, Northwest China, through studies of outcrop, core, well-log, and seismic data. They are characterized by thin to thick bedded mudstone, with contour current irregularly thin bedded-lentiform siltstone and sandstone. Chitin stone, graptolite, thin-shelled bivalve, dissoconch, and acritatch fossils are present in dark-colored mudstones. A Helminthopsis-Scolicia trace fossil assem-blage was observed in the outcrop and drilling core. Sandstones are mainly well-sorted and subangular-subrounded sublitharenite. Sedimentary structures include oriented current structure, erosional surface, and small-scale cross stratifications. The potential of contourites as hydrocarbon source and reservoir rocks was evaluated on the basis of previous interpretations of paleoclimate and paleosalinity.

关键词： Tarim basin Silurian hemipelagic deposit contourite.

A review of the use of pteridophytes for treating human ailments

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2018年第2期19卷 85-119页

作者： Xavier-ravi BASKARAN Antony-varuvel geo VIGILA Shou-zhou ZHANG Shi-xiu FENG Wen-bo LIAO State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources School of Life Sciences Sun Yat-sen University Shenzhen Key Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical Garden/Chinese Academy of Sciences Department of Zoology St.Xavier's College

The aim of this review was to explore the pharmacological activity of early tracheophytes （pteridophytes） as an alternative medicine for treating human ailments. As the first vascular plants, pteridophytes （aka, ferns and fern allies） are an ancient lineage, and human beings have been exploring and using taxa from this lineage for over 2000 years because of their beneficial properties. We have documented the medicinal uses of pteddophytes belonging to thirty different families. The lycophyte Selaginella sp. was shown in earlier studies to have multiple pharmacological activity, such as antioxidant, anti-inflammatory, anti-cancer, antidiabetic, antiviral, antimicrobial, and anti-Alzheimer properties. Among all the pteridophytes examined, taxa from the Pteridaceae, Polypodiaceae, and Adiantaceae ex- hibited significant medicinal activity. Based on our review, many pteridophytes have properties that could be used in alternative medicine for treatment of various human illnesses. Biotechnological tools can be used to preserve and even improve their bioactive molecules for the preparation of medicines against illness. Even though several studies have reported medicinal uses of ferns, the possible bioacUve compounds of several pteridophytes have not been identified. Furthermore, their optimal dosage level and treatment strategies still need to be determined. Finally, the future direc- tion of pteridophyte research is discussed.

关键词： Pteridophyte Fern Alternative medicine Selaginella Human illness Bioactive molecule

ON THE CHANGING AGRICULTURAL STRUCTURE AND ITS geoGRAPHIC STUDIES

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Journal of geographical Sciences 1995年第4期5卷 33-41页

作者： Zeng Zungu XiongXiangen(Department of geo and Ocean Sciences, Nanjing University, Nanjing 210008 People’s Republic of China)

The aghcultural structure is defined as an interactive combination of controllable factors, which constitutes a supporting framework of agricultural system. It is a dynamic structure which changes with economic development Currentiy in China, the traditional aghculture is gradually transforming into the modern one, and the changing agricultural structure attracts attention of experts from different disciplines. The authors of this artide sopt that geographers should actively take part in the Studies of agricultural structure changes, and the conopt of 'major agricultural system' should be accepted for the purpose of expanding the area of their sclentific investigation, encouraging theoredcal innovation, improving research methods and techniques, and serving agricultural modernization.

关键词： agricultural stucture agricultural system agricultural modernization agricultural geography

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太古汇的绿色屋顶和广场

景观设计 2015年第6期 32-37页

作者： Arquitectonica geo

该项目位于中国广州，总占地面积约45．7万平方米，是一个集多功能用途为一体的开发项目，囊括了银行、写字间、酒店、高层住宅、文化中心、零售商场、绿色屋顶以及花园广场等功能空间。设计师精心设计的方案提升了项目的可持续性，同... 详细信息

该项目位于中国广州，总占地面积约45．7万平方米，是一个集多功能用途为一体的开发项目，囊括了银行、写字间、酒店、高层住宅、文化中心、零售商场、绿色屋顶以及花园广场等功能空间。设计师精心设计的方案提升了项目的可持续性，同时以别出心裁的形式整合了景观空间，使其最大化，从而打造一个密集的多功能空间格局。

关键词：绿色屋顶广场多功能用途占地面积高层住宅文化中心零售商场功能空间