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On power allocation for a cognitive radio network with hybrid spectrum sharing

Science China(Information Sciences) 2011年第11期54卷 2425-2434页

作者： ZHANG Jing 1,2,3.& ZHU HongBo 1 1 Key laboratory of Wireless Communications of Jiangsu Province,nanjing university of Posts & Telecommunications,nanjing 210003.China 2 College of Electronic Science & Engineering,nanjing university of Posts & Telecommunications,nanjing 210003.China 3.state Key laboratory of Millimeter Waves,nanjing 210096,China 1. Key laboratory of Wireless Communications of Jiangsu Province Nanjing University of Posts & Telecommunications Nanjing 210003 China2. College of Electronic Science & Engineering Nanjing University of Posts & Telecommunications Nanjing 210003 China3. State Key Laboratory of Millimeter Waves Nanjing 210096 China

In this study we propose a hybrid spectrum sharing scheme based on power control by combining Overlay with Underlay schemes,to improve radio spectrum *** the scheme,the secondary users dynamically switch their operational states between Overlay and Underlay according to the spectrum *** the dynamics of the primary network is first modeled with a discrete-state Markov process to find the time fraction of secondary users in the Overlay state and that in the Underlay state,which leads to the capacity model of the hybrid spectrum sharing *** the criterion of maximizing capacity,the power allocation of the cognitive network is researched and the optimum power allocation for secondary users is *** a result,the maximum achievable capacity of the cognitive network is *** are given to prove the analysis *** and simulated results indicate that hybrid spectrum sharing based on power control provides a higher capacity than single Overlay and Underlay systems for the cognitive network,i.e.,hybrid spectrum sharing can further improve radio spectrum efficiency.

关键词： cognitive radio network hybrid spectrum sharing primary network dynamics power allocation achievable capacity

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Syntheses, properties and structures of copper and nickel complexes of 6,7-dihydro-5H-1,4-dithiepin-2,3.dithiolate

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Chinese Journal of Chemistry 1994年第3期12卷 248-257页

作者： YAO, Tian-Ming YOU, Xiao-ZengCoordination Chemistry Institute, state Key laboratory of Coordination Chemistry, nanjing university,{3. 210008, ChinaYANG, Qing-ChuanChemistry Department, Beijing university, Beijing 100871, China 1Coordination Chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210008 China2Chemistry Department Beijing University Beijing 100871 China

The reaction of CuCl2-2H2O or NiCl2.6H2O with K2(C5H6S4) [potassium salt of 6,7-dihydro-5H-1,4-dithiepin-2,3.dithiolate] under nitrogen atmosphere resulted in the isolation of [Cu(C5H6S4)2]- or [Ni(C5H6S4)2]- as the tetrabutylammonium salt. Both complexes show characteristic IR and UV-Vis absorptions of transition metal dithiolenes. Cyclic voltammograms contain two waves indicating a two step electrochemical procedure [M(C5H6S4)2]0 = [M(C5H6S4)2]1-= [M(C5H6S4)2]2-. Single crystal structure study has been carried out on the nickel complex. Crystal of [Bu4N][Ni(C5H6S4)2] belongs to monoclinic space group P21/c with a=17.576(5), 6=10.883.2), c=17.773.4) A,B=91.07(2)0, Z=4, and o(calcd.)=1.3.8 g/cm3. Final result is R=0.059 for 2959 reflections. The NiS4 core exhibits square planar coordination with average Ni-S bond length of 2.13.(5) A. There are not anion pairs in crystal. The anions stack along a and c axes while the cations intercalate in them. The nearest S-S contact is 4.429 A. The solid powder ESR spectrum of the nickel complex shows three broadening signals at g1=2.097, g2=2.042, g3.2.022. Magnetic susceptibility data for [Bu4N][Ni(CgH6S4)2] reveal enhanced anti-ferromagnetic interaction.

关键词： Dithiolene complex copper nickel single crystal.

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Structural properties of GaN(0001) epitaxial layers revealed by high resolution X-ray diffraction

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Science China(Physics,Mechanics & Astronomy) 2010年第1期53卷 68-71页

作者： XIE ZiLi 1,2,3. ZHOU YuanJun 1 , SONG LiHong 1,2 , LIU Bin 1 , HUA XueMei 1,2 , Xiu XiangQian 1 , ZHANG Rong 1,2,3.& ZHENG YouDou 1,2,3.1 JiangSu Provincial Key laboratory of Advanced Photonic and Electronic Materials and Department of Physics, nanjing university, nanjing 210093. China 2 nanjing national laboratory of microstructures, nanjing 210093. China 3.NJU-Yangzhou Institute of Opto-electronics, Yangzhou, 225001, China 1. JiangSu Provincial Key laboratory of Advanced Photonic and Electronic Materials and Department of Physics Nanjing University Nanjing 210093 China2. Nanjing National Laboratory of Microstructures Nanjing 210093 China3. NJU-Yangzhou Institute of Opto-electronics Yangzhou 225001 China

High-resolution X-ray diffraction has been used to analyze GaN(0001) epitaxial layers on sapphire substrates. Several structural properties of GaN, including the lattice constants, strains, and dislocation densities are revealed by the technique of X-ray dffraction (XRD). Lattice constants calculated from the omega/2theta scan are c=0.5185 nm and a=0.3.57 nm. Also, the in-plane strain is -1.003., while out of the plane, the epitaxial film is almost relaxed. Several methods are used to deduce the mosaicity and dislocation density of GaN, showing that the edge type dislocations are the overwhelming majority.

关键词： GaN XRD dislocation epitaxial

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Effects of chlorothalonil and carbendazim on nitrification and denitrification in soils

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Journal of Environmental Sciences 2009年第4期21卷 458-467页

作者： LANG Man, CAI Zucong state Key laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences,nanjing {3., China [a]state Key laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

The effects of chlorothalonil and carbendazim on nitrification and denitrification in six soils in upland and rice paddy environments were investigated. laboratory aerobic （60% water holding capacity） and anaerobic （flooded） conditions were studied at 25℃ and fungicide addition rates of 5.5 mg/kg A. I. （field rate, FR）, 20 times （20FR） and 40 times （40FR） field rate, respectively. The results indicated that chlorothalonil at the field rate had a slight inhibitory effect on one soil only, and that soil did not nitrify much in the first place. But chlorothalonil at higher rates inhibited nitrification significantly in all soils. For soils JXP and JXU with a pH of less than 5.0, chlorothalonil almost completely stopped their nitrification at 20FR and 40FR during the whole 14 d incubation period. For soils HNP and HNU with a pH of greater than 8.0, chlorothalonil also significantly inhibit nitrification at 20FR and 40FR （p 〈 0.05）. However, NH4＋ that was added to the soil was also almost completely nitrified by the end of the incubation period in these two soils. The effects of chlorothalonil at 20FR and 40FR on the nitrification of JSP and JSU soils, with a pH of 5.4 and 7.2, respectively, were intermediate between the other soil types. Chlorothalonil had no effect on denitrification at the field rate and had little effect at the higher rates of application in some soils. Carbendazim had essentially no effect on nitrification and denitrification in soils assessed.

关键词： fungicide nitrification denitrification chlorothalonil carbendazim

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EPR AND HIGH RESOLUTION SOLID-state NMR STUDIES ON Fe^(3.) SUBSTITUTED ZSM-5 ZEOLITE

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Chinese Chemical Letters 1991年第3期2卷 249-250页

作者： Wen Xia SHEN Ying YU Yi Chun YEN Ying Ru DING Department of Chemistry,nanjing university,nanjing {3. Cheng HU laboratory of Solid state microstructures,nanjing Univ.{3.

Fe^(3.) substituted ZSM-5 zeolite was studied using EPR and ^(27)A1,^(29)Si MAS-NMR *** results showed that the synthe- sized sample has the typical ZSM-5 structure with Fe^(3.) ionsincorporated in tetrahedric sites i... 详细信息

关键词： Fe EPR AND HIGH RESOLUTION SOLID-state NMR STUDIES ON Fe SUBSTITUTED ZSM-5 ZEOLITE NMR

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Synthesis of Two Nucleotide Derivatives with Phosphate Replaced by Vanadate

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Chinese Chemical Letters 1997年第5期8卷 401-402页

作者： De Ping XUE Ji Mei MIN Li He ZHANG Kui WANG(Coordination Chedstry Institute,nanjing university,nanjing {3.)(national laboratory of Natural and Biomboic Drug,Beijing Medical university,Beijing 100083. nanjing UNIV INST COORDINAT CHEMNANJING 210008PEOPLES R CHINA BEIJING MED UNIV NATL LAB NAT & BIOMIM DRUGSBEIJING 100083PEOPLES R CHINA

Two kinds of vanadyl nucleotide were synthesized from vanadyl trichloride with adenosine derivatives.

关键词： DMSO 亚砜 MHz

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Field-effect transistors based on two-dimensional materials for logic applications

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Chinese Physics B 2013年第9期22卷 147-161页

作者：王欣然施毅张荣 national laboratory of microstructures and School of Electronic Science and Engineering Nanjing University

Field-effect transistors （FETs） for logic applications, graphene and MoS2, are discussed. These materials have based on two representative two-dimensional （2D） materials, drastically different properties and require different consider- ations. The unique band structure of graphene necessitates engineering of the Dirac point, including the opening of the bandgap, the doping and the interface, before the graphene can be used in logic applications. On the other hand, MoS2 is a semiconductor, and its electron transport depends heavily on the surface properties, the number of layers, and the carrier density. Finally, we discuss the prospects for the future developments in 2D material transistors.

关键词： graphene MoS2 two-dimensional (2D) materials field-effect transistors

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A self-steering close-talking microphone array

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Progress in Natural Science:Materials International 2005年第11期15卷 1044-1049页

作者： PENG Ke, YANG Xinfeng and XU Boling (state Key laboratory of Modern Acoustics, Institute of Acoustics, nanjing university, {3. 210093. China) state Key laboratory of Modern Acoustics Institute of Acoustics Nanjing University Nanjing 210093 China

For communication in extremely noisy environments, close-talking microphone arrays are useful. Differential microphone array systems possessing excellent nearfield directivity and strong farfield-noise reduction capability are very suitable for close-talking situations. In order to improve the focusing effect at the desired bearing in the nearfield, we propose a novel self-steering system of close-talking arrays with the first-order differential sub-arrays in this paper. Calculations of directivity patterns and directivity factors show that when a kind of optimized beamforming technique is adopted even small arrays with a focusing configuration will exhibit a satisfactory nearfield directivity which is electronically steerable within a specific range. The superiority of the proposed array system is verified by experiments with real acoustic data.

关键词： close-talking array differential array self-steering directivity factor.

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Special magnetic phenomena in heavily doped La_(0.7-x)Dy_xSr_(0.3.MnO_3.system

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Science China(Physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2 ,YAN GuoQing 1,3.,CAI ZhiRang 1 ,PI Li 2 ,ZHANG Bei 2 &TONG Wei 2 1 Department of Physics,Suzhou College,Suzhou 23.000,China 2 Structure Research laboratory,university of Science and Technology of China,Hefei 23.026,China 3.national laboratory of Solid state microstructures,Physics Department,nanjing university,nanjing 210093.China 1. Department of Physics Suzhou College Suzhou 234000 China 2. Structure Research laboratory University of Science and Technology of China Hefei 230026 China 3. national laboratory of Solid state {3. Physics Department Nanjing University Nanjing 210093 China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3.nO3.0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model

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A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2, PENG Shanchi~ 2,3., YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. College of Resource and Environment of Guizhou university, Guiyang 550003. China 2. nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, nanjing 210008, China 3. {3. Key laboratory of Papaeobiology and Stratigraphy, nanjing Institute of Geology and Palaeontology, nanjing 210008, China 4. Department of Geological Science, Ohio {3. university, Columbus, OH 43.10, USA 5. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China) College of Resource and Environment of Guizhou university Guiyang 550003 China nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China state Key laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological Science Ohio State University Columbus OH 43210 United States Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, China and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 193., are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003.is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12 segments, and a small pygidium that bears 2—3.axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3.and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962 or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

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