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Chinese Journal of Structural Chemistry 2006年第12期25卷 1449-1452页

作者：傅绪成聂丽张强李明田王小燕 Chemistry and Biology department West Anhui University department of Chemistry Central China Normal University

The title complex [CaCo（C3H2O4）2（H2O）4]n with a formula of C6HI2CaCoO12 and Mr=375.17 has been synthesized and structurally characterized by X-ray diffraction. The crystal is of monoclinic, space group C2/c with a = 14,195（9）, b = 7.708（5）, c = 13.441（8） A, β =119.575（9）°, V = 1279.0（14） A3, Dc= 1.948 g/cm^3,μ=1.803 mm^-1, F（000） = 764 and Z = 4. The final R = 0.0245 and wR = 0.0652 for 1344 observed reflections with I 〉 2σ（I）. The structure of the title complex consists of CaO8 polyhedra and CoO6 octahedra linked together by malonate ligands. The Ca（Ⅱ） cation on a twofold axis is coordinated by two water molecules and six malonate O atoms. The Co（Ⅱ） cation which lies in a centre of symmetry in an octahedral arrangement is coordinated by four malonate O atoms and two water molecules, The structure comprises alternating layers along the [101] plane, with the shortest Co-Co distance of 6.961（5）A. The whole 3D structure is maintained and stabilized by the presence of hydrogen bonds.

关键词： calcium cobalt crystal structure malonate

Crystal Growth and Characterization of Potassium Manganese Nickel Sulphate Hexahydrate—A New UV Filter

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Journal of Minerals and Materials Characterization and Engineering 2012年第11期11卷 1121-1125页

作者： Vanitha Duraikkan Sultan Asath Bahadur Shunmuganarayanan Athimoolam department of Physics Kalasalingam University Krishnankoil India department of Physics University College of Engineering Anna University of Technology Thirunelveli India

Potassium Manganese Nickel Sulphate Hexahydrate (KMNSH) crystals have been successfully grown by using traditional slow evaporation method. The empirical formula of KMNNSH is K2Mn0.1Ni0.9 (SO4)2?6H2O with formula weight 430.7698. KMNNSH crystal revealed monoclinic space group P2(1)/c, a = 6.12(4) ?, b = 12.19(9) ?, c = 8.96(7) ?, α = γ = 90?, β = 105.3(2), V = 645(1)?3, Z = 2, Dc = 2.2281 g/cm3 with deep green color. IR confirms that there is strong interaction between free water molecules. The thermal analysis indicates that the water molecules are present in the KMNNSH crystals. The transmission spectrometry of KMNNSH in the range from UV to near IR wavelengths is reported. Atomic Absorption Spectroscopy also have been studied and discussed.

关键词： Ultraviolet Filter Potassium Manganese Nickel Sulphate Transmission Spectrum Thermal Stability

A Study of Banach Fixed Point Theorem and It’s Applications

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American Journal of Computational Mathematics 2021年第2期11卷 157-174页

作者： Md. Abdul Mannan Md. R. Rahman Halima Akter Nazmun Nahar Samiran Mondal department of Mathematics Uttara University Dhaka Bangladesh department of Computer Science & Engineering Prime University Dhaka Bangladesh department of Mathematics Jashore University of Science and Technology Jashore Bangladesh

This paper aims at treating a study of Banach fixed point theorem for mapping results that introduced in the setting of normed space. The classical Banach fixed point theorem is a generalization of this work. A fixed point theory is a beautiful mixture of Mathematical analysis to explain some conditions in which maps give excellent solutions. Here later many mathematicians used this fixed point theory to establish their results, see for instance, Picard-Lindel of Theorem, The Picard theorem, Implicit function theorem etc. Also, we developed ideas that many of known fixed point theorems can easily be derived from the Banach theorem. It extends some recent works on the extension of Banach contraction principle to metric space with norm spaces.

关键词： Metric space Norm space Complete Norm space Operator Banach Fixed Point Theorem Uniformity Strong and Weak contraction Semi-Continuous

China’s Recent Progresses in Polar Climate Change and Its Interactions with the Global Climate System

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Advances in Atmospheric Sciences 2023年第8期40卷 1401-1428页

作者： Xichen LI Xianyao CHEN Bingyi WU Xiao CHENG Minghu DING Ruibo LEI Di QI Qizhen SUN Xiaoyu WANG Wenli ZHONG Lei ZHENG Meijiao XIN Xiaocen SHEN Chentao SONG Yurong HOU Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Frontier Science Center for Deep Ocean Multispheres and Earth System and Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100China Qingdao National Laboratory for Marine Science and technology Qingdao 266061China department of Atmospheric and Oceanic Sciences/Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China CMA-FDU Joint Laboratory of Marine Meteorology Shanghai 200438China School of geospatial Engineering and Science Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Sun Yat-sen UniversityZhuhai 519082China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Key Laboratory for Polar Science of the MNR Polar Research Institute of ChinaShanghai 200136China Polar and Marine Research Institute Jimei UniversityXiamen 361021China Polar Research and Forecasting Division National Marine Environmental Forecasting CenterBeijing 100081China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

During the recent four decades since 1980,a series of modern climate satellites were launched,allowing for the measurement and record-keeping of multiple climate parameters,especially over the polar regions where traditional observations are difficult to *** has been actively engaging in polar *** observations were conducted during this period,accompanied by improved Earth climate models,leading to a series of insightful understandings concerning Arctic and Antarctic climate ***,we review the recent progress China has made concerning Arctic and Antarctic climate change research over the past *** Arctic temperature increase is much higher than the global-mean warming rate,associated with a rapid decline in sea ice,a phenomenon called the Arctic *** Antarctic climate changes showed a zonally asymmetric pattern over the past four decades,with most of the fastest changes occurring over West Antarctica and the Antarctic *** Arctic and Antarctic climate changes were driven by anthropogenic greenhouse gas emissions and ozone loss,while tropical-polar teleconnections play important roles in driving the regional climate changes and extreme events over the polar *** climate changes may also feedback to the entire Earth climate *** adjustment of the circulation in both the troposphere and the stratosphere contributed to the interactions between the polar climate changes and lower *** change has also driven rapid Arctic and Southern ocean *** researchers have made a series of advances in understanding these processes,as reviewed in this paper.

关键词： polar climate change recent progress in China Arctic amplification tropical-polar interactions global sea level rise stratospheric circulation

An Efficient space-Time Coding Scheme for Time Dispersive MIMO Channels

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International Journal of Communications, Network and System Sciences 2012年第4期5卷 218-221页

作者： Salim Abdelkareem Alkhawaldeh Electrical Engineering department Faculty of Engineering Technology Albalqa Applied University Amman Jordan

In this paper, we introduce an efficient space-time coding scheme for time dispersive Multiple-Input Multiple-Output (MIMO) channels. Channel layering and Orthogonal Frequency Division Multiplexing (OFDM) technique are used in the proposed scheme. The proposed scheme is based on maximizing the distance between any two codewords. This is done by inserting an optimized phase shifts between the symbols in the same layer and between different layers. This way leads to the increase of the achieved diversity and coding gains. As a result, the performance of the system will be improved. Simulation results show the efficiency of the proposed scheme compared to the conventional schemes.

关键词： OFDM Fading space-Time Coding Diversity MIMO

Synthesis and Crystal Structure of 4-(4-Chlorophenyl)-6-methyl-5-methoxy-caronyl-3,4-dihydropyrimidin-2(H)-one

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Chinese Journal of Structural Chemistry 2004年第11期23卷 1295-1299页

作者：华国平屠树江房芳屠蔓苏史达清王香善纪顺俊张勇 Xuzhou Institute of Architectural technology Xuzhou Jiangsu 221008 China department of Chemistry Xuzhou Normal University Key Laboratory of Biotechnology on Medical Plant of Jiangsu Province Xuzhou Jiangsu 221009 China College of Chemistry and Chemical Engineering Key Lab of Organic Synthesis of Jiangsu Province Suzhou University Jiangsu 215006 China

The title compound 4-(4-chlorophenyl)-6-methyl-5-methoxy-caronyl-3,4-dihydro- pyrimidin-2(H)-one has been synthesized by the reaction of 4-chlorobenzaldehyde, methyl acetoa- cetate and urea using H3BO3 as a catalyst under microwave irradiation. Its structure was charac- terized by X-ray single-crystal diffraction techniques with the following data: triclinic, space group P1, a = 5.4513(4), b = 7.619(1), c = 16.118(4) ?, α = 80.42(1), β = 83.43(1), γ = 79.29(1)°, V = 646.19(19) ?3, Mr = 280.70, μ(MoKα) = 0.301 mm-1, Z = 2 and Dc = 1.443 g/cm3. In the molecule the pyrimidine ring is of boat conformation.

关键词： microwave irradiation 3,4-dihydropyrimidinone H3BO3 crystal structure

Some Integral Type Fixed Point Theorems in Dislocated Metric space

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American Journal of Computational Mathematics 2016年第2期6卷 88-97页

作者： Dinesh Panthi Panda Sumati Kumari department of Mathematics Valmeeki Campus Nepal Sanskrit University Kathmandu Nepal department of Mathematics National Institute of Technology Andhra Pradesh Tadepalligudem India

In this article, we establish a common fixed point theorem satisfying integral type contractive condition for two pairs of weakly compatible mappings with E. A. property and also generalize Theorem (2) of B.E. Rhoades... 详细信息

关键词： Dislocated Metric Weakly Compatible Maps Common Fixed Point

Reservoir Characterization and Geostatistical Modeling of Ilam &Sarvak Formations in One of Oil Fields in Southwest of Iran

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Open Journal of Geology 2017年第6期7卷 789-795页

作者： Neda Sasaninia Davoud Jahani Bahram Habibnia Nader Kohansal Ghadimvand department of Geology Tehran North Branch Islamic Azad University Tehran Iran department of Petroleum Exploration Petroleum University of Technology Abadan Iran

Exploration and exploitation of hydrocarbon reservoirs have been always time consuming with high risk and high cost. In this regard, assessment of reservoir characterizations and information about spatial distribution of its parameters play an important role in adaptation of suitable strategies for hydrocarbon resources management. There are only few numbers of oil wells cored in every oil field due to high cost, time-consuming process, and other drilling problems. Therefore, it is required to use alternative estimation methods in order to achieve the petro-physical parameter in total space of reservoir. In this research, geostatistical methods have been applied as a new approach to calculate and estimate porosity and permeability of reservoir in one of southwestern oil fields of Iran. The information obtained from 86 wells in one of southwestern oil fields of Iran has been available in this study. Physical parameters of porosity and permeability are vital parameters that should be estimated in studied reservoir. This study indicated that Gaussian Variogram Model is the best model to predict porosity and permeability values in field. Error means of actual values of porosity are equal to 6.9% and for permeability are 11.21% using Gaussian Model. Also, after prediction of porosity and permeability values for field, distribution of these parameters in field was illustrated in two-dimensional and three-dimensional modes besides distribution and location of wells in field in order to determine the best drilling spots and reduce risk of drilling operations.

关键词： Porosity Permeability Geostatistics Krigging

A resonator mode in linear arrays of silver spheres and cylinders

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第1期7卷 29-33页

作者： SIMOVSKI C.R. VIITANEN A.J. TRETYAKOV S.A. department of Photonics and Optical Informatics State University of Information Technologies 197101 Sablinskaya 14 St. Petersburg Russia Electromagnetic Laboratory Helsinki University of Technology FI-02015 Espoo Finland Radio Laboratory SMARAD Helsinki University of Technology FI-02015 Espoo Finland

A transversal mode with zero group velocity and non-zero phase velocity that can exist in chains of silver nano- spheres in the optical frequency range was theoretically studied. It is shown that the external source radiating a narrow-band non-monochromatic signal can excite in the chain a mixture of standing and slowly travelling waves. The standing wave com- ponent (named as resonator mode) is strongly dominating. The physical reason of such a regime is a sign-varying distribution of power flux over the cross section of the chain. This situation is similar to the scenario of the propagation of a wave along the boundary between the right-handed and left-handed media where the spatial distribution of the light intensity is vortex. However, in the present case there is no boundary between media and the boundary between the positive and negative power fluxes is a cylindric tube in free space whose axis is the axis of the chain.

关键词： Resonator mode Linear arrays Plasmon particle

Observation of the Crab Nebula with LHAASO-KM2A−a performance study

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Chinese Physics C 2021年第2期45卷 518-530页

作者： F.Aharonian Q.An Axikegu L.X.Bai Y.X.Bai Y.W.Bao D.Bastieri X.J.Bi Y.J.Bi H.Cai J.T.Cai Z.Cao J.Chang J.F.Chang X.C.Chang B.M.Chen J.Chen L.Chen M.J.Chen M.L.Chen Q.H.Chen S.H.Chen S.Z.Chen T.L.Chen X.L.Chen Y.Chen N.Cheng Y.D.Cheng S.W.Cui X.H.Cui Y.D.Cui B.Z.Dai H.L.Dai Z.G.Dai D.della Volpe B.D'Ettorre Piazzoli X.J.Dong J.H.Fan Y.Z.Fan Z.X.Fan J.Fang K.Fang C.F.Feng L.Feng S.H.Feng Y.L.Feng B.Gao C.D.Gao Q.Gao W.Gao M.M.Ge L.S.Geng G.H.Gong Q.B.Gou M.H.Gu J.G.Guo X.L.Guo Y.Q.Guo Y.Y.Guo Y.A.Han H.H.He H.N.He J.C.He S.L.He X.B.He Y.He M.Heller Y.K.Hor C.Hou X.Hou H.B.Hu S.Hu S.C.Hu X.J.Hu D.H.Huang Q.L.Huang W.H.Huang X.T.Huang Z.C.Huang F.Ji X.L.Ji H.Y.Jia K.Jiang Z.J.Jiang C.Jin D.Kuleshov K.Levochkin B.B.Li C.Li F.Li H.B.Li H.C.Li H.Y.Li J.Li K.Li W.L.Li X.Li X.R.Li Y.Li Y.Z.Li Z.Li E.W.Liang Y.F.Liang S.J.Lin B.Liu C.Liu D.Liu H.Liu H.D.Liu J.Liu J.L.Liu J.S.Liu J.Y.Liu M.Y.Liu R.Y.Liu S.M.Liu W.Liu Y.N.Liu Z.X.Liu W.J.Long R.Lu H.K.Lv B.Q.Ma L.L.Ma X.H.Ma J.R.Mao A.Masood W.Mitthumsiri T.Montaruli Y.C.Nan B.Y.Pang P.Pattarakijwanich Z.Y.Pei M.Y.Qi D.Ruffolo V.Rulev A.Sáiz L.Shao O.Shchegolev X.D.Sheng J.R.Shi H.C.Song Yu.V.Stenkin V.Stepanov Q.N.Sun X.N.Sun Z.B.Sun P.H.T.Tam Z.B.Tang W.W.Tian B.D.Wang C.Wang H.Wang H.G.Wang J.C.Wang J.S.Wang L.P.Wang L.Y.Wang R.N.Wang W.Wang X.G.Wang X.J.Wang X.Y.Wang Y.D.Wang Y.J.Wang Y.P.Wang Z.Wang Z.H.Wang Z.X.Wang D.M.Wei J.J.Wei Y.J.Wei T.Wen C.Y.Wu H.R.Wu S.Wu W.X.Wu X.F.Wu S.Q.Xi J.Xia J.J.Xia G.M.Xiang G.Xiao H.B.Xiao G.G.Xin Y.L.Xin Y.Xing D.L.Xu R.X.Xu L.Xue D.H.Yan C.W.Yang F.F.Yang J.Y.Yang L.L.Yang M.J.Yang R.Z.Yang S.B.Yang Y.H.Yao Z.G.Yao Y.M.Ye L.Q.Yin N.Yin X.H.You Z.Y.You Y.H.Yu Q.Yuan H.D.Zeng T.X.Zeng W.Zeng Z.K.Zeng M.Zha X.X.Zhai B.B.Zhang H.M.Zhang H.Y.Zhang J.L.Zhang J.W.Zhang L.Zhang L.X.Zhang P.F.Zhang P.P.Zhang R.Zhang S.R.Zhang S.S.Zhang X.Zhang X.P.Zhang Y.Zhang Y.F.Zhang Y.L.Zhang B.Zhao J.Zhao L.Zhao L.Z.Zhao S.P.Zhao F.Zheng Y.Zheng B.Zhou H.Zhou J.N.Zhou P.Zhou R.Zhou X.X.Zhou C.G.Zhu F.R.Zhu H.Zhu K.J.Zhu X.Zuo Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of Sciences100049 BeijingChina University of Chinese Academy of Sciences 100049 BeijingChina TIANFU Cosmic Ray Research Center ChengduSichuanChina State Key Laboratory of Particle Detection and Electronics China University of Science and technology of China 230026 HefeiAnhuiChina department of Engineering Physics Tsinghua University100084 BeijingChina National Astronomical Observatories Chinese Academy of Sciences100101 BeijingChina National space Science Center Chinese Academy of Sciences100190 BeijingChina School of Physics Peking University100871 BeijingChina Center for Astrophysics Guangzhou University510006 GuangzhouGuangdongChina School of Physics and Astronomy&School of Physics(Guangzhou) Sun Yat-sen University519000 ZhuhaiGuangdongChina School of Physical Science and technology Guangxi University530004 NanningGuangxiChina Hebei Normal University 050024 ShijiazhuangHebeiChina School of Physics and Microelectronics Zhengzhou University450001 ZhengzhouHenanChina School of Astronomy and space Science Nanjing University210023 NanjingJiangsuChina Key Laboratory of Dark Matter and space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences210023 NanjingJiangsuChina Institute of Frontier and Interdisciplinary Science Shandong University266237 QingdaoShandongChina Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of Sciences200030 ShanghaiChina Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong University200240 ShanghaiChina School of Physical Science and technology&School of Information Science and technology Southwest Jiaotong University610031 ChengduSichuanChina College of Physics Sichuan University610065 ChengduSichuanChina Key Laboratory of Cosmic Rays(Tibet University) Ministry of Education850000 LhasaTibetChina School of Physics and Tec

A sub-array of the Large High Altitude Air Shower Observatory(LHAASO),KM2A is mainly designed to observe a large fraction of the northern sky to hunt for γ-ray sources at energies above 10 *** though the detector construction is still underway,half of the KM2A array has been operating stably since the end of *** this paper,we present the KM2A data analysis pipeline and the first observation of the Crab Nebula,a standard candle in very high energy γ-ray *** detect γ-ray signals from the Crab Nebula in both energy ranges of 10-100 TeV and>100 TeV with high significance,by analyzing the KM2A data of 136 live days between December 2019 and May *** the observations,we test the detector performance,including angular resolution,pointing accuracy and cosmic-ray background rejection *** energy spectrum of the Crab Nebula in the energy range 10-250 TeV fits well with a single power-law function dN/dE=(1.13±0.05stat±0.08sys)×10^(-14).(E/20 TeV)-309±0.06stat±0.02syscm^(-2) s^(-1) TeV^(-1).It is consistent with previous measurements by other *** opens a new window of γ-ray astronomy above 0.1 PeV through which new ultrahigh-energy γ-ray phenomena,such as cosmic PeVatrons,might be discovered.

关键词： γ-ray Crab Nebula extensive air showers cosmic rays