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Bacterial community in deep subseafloor sediments from the western Pacific "warm pool"

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science China Earth sciences 2008年第4期51卷 618-624页

作者： ZHAO Jing1 & ZENG RunYing2 1 college of Oceanography and Environmental science, Xiamen University, Xiamen 361005, China 2 Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China college of Oceanography and Environmental science Xiamen University Xiamen China Key Laboratory of Marine Biogenetic Resources Third Institute of Oceanography State Oceanic Administration Xiamen China

The bacterial community in deep subseafloor sediments at a depth of 230 cm from the western Pacific "warm pool" is studied by construction of 16S rDNA clone library and PCR-RFLP (Restriction Fragment Length Polymorphism) analysis. The results indicate that the bacterial community in these sediments is mainly composed of five groups: α-Proteobacteria, β-Proteobacteria, CFB group (Cytophaga / Flexi-bacteria / Bacteroides), Acidobacteria and gram positive bacteria, with a few genera detected in each group. The most abundant bacteria group is α-Proteobacteria, and the next is β-Proteobacteria. The dominant species in α-and β-Proteobacteria are Sphingomonas paucimobilis and Pseudomonas alca-ligenes respectively. The CFB group is simply composed of members belonging to Flavobacterium. The gram positive bacteria are rich, and mainly consists of the genus Geobacillus. The analysis of bacterial community indicates that organic matter is still abundant in the subseafloor sediments at the depth of 230 cm in the western Pacific "warm pool" . These bacteria in this deep biosphere may play an impor-tant role in the nitrogen cycle of deep sea sediments at "warm pool" .

关键词： western Pacific 'warm pool' deep subseafloor sediment bacterial community

Estimation of wall parameters based on range profiles

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science China(Information sciences) 2011年第10期54卷 2178-2189页

作者： LI Xin 1 ,AN DaoXiang 1,HUANG XiaoTao 1 & PENG ShiRui 2 1 college of Electronic science and Engineering,National Uniersity of Defense Technology,Changsha 410073,China 2 Department of Information Counter Measurement Airforce Radar Academy,Wuhan 430019,China college of Electronic science and Engineering National Uniersity of Defense Technology Changsha China Department of Information Counter Measurement Airforce Radar Academy Wuhan China

Compensation of wall effects is of main concern in SAR through-wall *** parameters are essential for the compensation,which are normally not known a priori.A model of SAR working in sidelooking strip mode for through-wall imaging is established,with the path of signal due to refraction taken into *** analyzing the echo configuration in time domain,a new procedure for estimating wall parameters using high range resolution profiles is *** extracting time delay of target counterpart,the thickness and permittivity of wall are figured out exactly by employing numerical equation method and intersecting of searching *** the estimated parameters,focused image of targets in a room is acquired after wall effects are compensated in imaging processing with back projection *** results verify the validity of the theoretical analysis and imaging algorithm.

关键词： synthetic aperture radar (SAR) range profiles parameters estimation wall compensation

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2, LIU Chang-hua2, ZHANG He-bing2 1. college of Resources science and Technology, Beijing Normal University, Beijing 100875, China 2. School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, China college of Resources science and Technology Beijing Normal University Beijing 100875 China School of Surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine

Probabilistic teleportation via a non-maximally entangled GHZ state

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Chinese science Bulletin 2010年第10期55卷 902-906页

作者： YAN FengLi1,2 & YAN Tao1,2 1 college of Physics science and Information Engineering,Hebei Normal University,Shijiazhuang 050016,China 2 Hebei Advanced Thin Films Laboratory,Shijiazhuang 050016,China college of Physics science and Information Engineering Hebei Normal University Shijiazhuang China Hebei Advanced Thin Films Laboratory Shijiazhuang China

We present a scheme for probabilistic teleportation via a non-maximally entangled GHZ *** teleportation will succeed with a calculable *** teleportation process requires the sender to make a generalized Bell state measurement,the cooperator to perform a generalized X basis measurement,and the receiver to perform a collective unitary transformation and to make a measurement on an auxiliary *** success probability of the teleportation is *** also obtain the maximum of the success probability of the teleportation.

关键词：成功概率 GHZ态隐形传送纠缠 Bell态测量量子隐形传态传输过程辅助粒子

Diophantine vectors in analytic submanifolds of Euclidean spaces

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science China Mathematics 2007年第9期50卷 1334-1338页

作者： Rong-mei CAO~(1+) Jian-gong YOU~2 1 college of science,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China 2 Department of Mathematics,Nanjing University,Nanjing 210093,China college of science Nanjing University of Aeronautics and Astronautics Nanjing China Department of Mathematics Nanjing University Nanjing China

Let $\mathcal{M}$ be an m-dimensional analytic manifold in ? n . In this paper, we prove that almost all vectors in $\mathcal{M}$ (in the sense of Lebesgue measure) are Diophantine if there exists one Diophantine vect... 详细信息

关键词： diophantine vector analytic submanifold 32C05

Theoretical study of the interaction mechanism of single-electron halogen bond complexes H_3C…Br-Y(Y=H,CN,NC,CCH,C_2H_3)

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science China Chemistry 2010年第1期53卷 216-225页

作者： LI ZhiFeng1,SHI XiaoNing1,TANG HuiAn1 & ZHANG JunYan2 1college of Life science and Chemistry,Tianshui Normal University,Tianshui 741001,China 2Lanzhou Institute of Chemical Physics,Chinese Academy of sciences,Lanzhou 730000,China college of Life science and Chemistry Tianshui Normal University Tianshui China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

The characteristics and structures of single-electron halogen bond complexes H3C…Br-Y(Y = H,CCH,CN,NC,C2H3) have been investigated by theoretical calculation *** geometries were optimized and frequencies calculated at the B3LYP/6-311++G *** interaction energies were corrected for basis set superposition error(BSSE) and the wavefunctions obtained by the natural bond orbital(NBO) and atom in molecule(AIM) analyses at the MP2/6-311++G *** each H3C…Br-Y complex,a single-electron Br bond is formed between the unpaired electron of the CH3(electron donor) radical and the Br atom of Br-Y(electron acceptor);this kind of single-electron bromine bond also possesses the character of a"three-electron bond".Due to the formation of the single-electron Br bond,the C-H bonds of the CH3 radical bend away from the Br-Y moiety and the Br-Y bond elongates,giving red-shifted single-electron Br bond *** effects of substituents,hybridization of the carbon atom,and solvent on the properties of the complexes have been *** strengths of single-electron hydrogen bonds,single-electron halogen bonds and single-electron lithium bonds have been *** addition,the single-electron halogen bond system is discussed in the light of the first three criteria for hydrogen bonding proposed by Popelier.

关键词： single-electron halogen bond single-electron hydrogen bond single-electron lithium bond MP2 DFT NBO AIM

Deformation and Densification Laws of Powder Cold Forging

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Journal of Wuhan University of Technology(Materials science) 2007年第1期22卷 17-21页

作者：余世浩 college of Material science and Engineering Wuhan University of Technology

The deformation and densification laws of preform upsetting and closed-die forging were researched based on experimental results of cold forging of deoxidized Fe powder sintering porous material under different initial conditions such as friction factor, ratio between height and diameter and relative density. The fracture limit criteria＂ for powder cold-forging upsetting and the limit strain curve were achieved. The effect of friction facto,, ratlt, between height and diameter and relative density on fracture strain limitation was emphatically analyzed. The limit process parameter curves for the deformation of upsetting were also confirmed. Laws of deformation, densification and density distribution for closed-die forging of powder perform during cold-forging were further analyzed and discussed with the help of experimental phase analysis. As a result, this experiment established theoretical foundations for the design of preform and die as well as optimization of technological process parameters.

关键词： powder cold-forging fracture limit strain criterion deformation law densification mechanism

Approximation algorithm for minimizing relay node placement in wireless sensor networks

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science China(Information sciences) 2010年第11期53卷 2332-2342页

作者： LU KeZhong1,2, CHEN GuoLiang1,2, FENG YuHong1,2, LIU Gang1,2 & MAO Rui1,2 1college of Computer science and Software Engineering, Shenzhen University, Shenzhen 518060, China 2National High Performance Computing Center at Shenzhen, Shenzhen 518060, China college of Computer science and Software Engineering Shenzhen University Shenzhen China National High Performance Computing Center at Shenzhen Shenzhen China

To eliminate the routing load unbalance among sensor nodes, one approach is to deploy a small number of powerful relay nodes acting as routing nodes in wireless sensor networks, the major optimization objective of which is to minimize the number of relay nodes required. In this paper, we prove that the relay node placement problem in a bounded plane is a P problem, but its computational complexity in general case is quite great. From the geometric cover feature of the relay node placement problem, an O(n2 log n) time greedy approximation algorithm is proposed, where n is the number of sensor nodes. Particularly, at each stage of this algorithm's iterative process, we first select a critical node from uncovered sensor nodes, and then determine the location of relay node based on the principle of preferring to cover the sensor node closer to the critical node, so as to prevent the emergence of isolated node. Experiment results indicate that our proposed algorithm can generate a near optimum feasible relay node deployment in a very short time, and it outperforms existing algorithms in terms of both the size of relay node deployment and the execution time.

关键词： wireless sensor network relay node placement geometrical cover approximation algorithm greedy algorithm

Analysis of a kind of quantum cryptographic schemes based on secret sharing

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science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1313-1316页

作者： ZHANG XingLan1 & JI DongYao2 1 college of Computer science and Technology, Beijing University of Technology, Beijing 100124, China 2 State Key Laboratory of Information Security, Graduate University of Chinese Academy of sciences, Beijing 100049, China college of Computer science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China

Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share's holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failure at last. Moreover, these schemes encounter another serious attack. Any two participants can co-operate to defeat the schemes by sending different shares to the parties unknown to the distributor of the secret K, such that these parties can execute the protocol as well. The attack proves that it is not enough for quantum cryptographic schemes that only the secret key is secure.

关键词： quantum identity authentication quantum secure direct communication quantum signature secret sharing