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Systematic study of survival probability of excited superheavy nuclei

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2.3.& ZHOU ShanGui2.3.1College of Applied Sciences, {2. University of Technology, {2. 10012., china 2.nstitute of Theoretical Physics, {3. Academy of Sciences, {2. 100190, china 3.enter of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 73.000, china College of Applied Sciences Beijing University of Technology Beijing China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China

The stability of excited superheavy nuclei (SHN) with 100 Z 13. against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission

On the local wellposedness of 3.D water wave problem with vorticity

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Science china Mathematics 2007年第8期50卷 1065-1077页

作者： Ping ZHANG~1 Zhi-fei ZHANG~2.1 Academy of Mathematics and Systems Science,chinese Academy of Sciences,beijing {2.,{3. 2.School of Mathematical Sciences,Peking University,beijing 100871,{3. Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China School of Mathematical Sciences Peking University Beijing China

In this article, we first present an equivalent formulation of the free boundary problem to 3.D incompressible Euler equations, then we announce our local wellposedness result concerning the free boundary problem in Sobolev space provided that there is no self-intersection point on the initial surface and under the stability assumption that $\frac{{\partial p}}{{\partial n}}(\xi )\left| {_{t = 0} } \right. \leqslant - 2._0 < 0$ being restricted to the initial surface.

关键词： water-waves free boundary incompressible Euler equations primary 3.Q3. 76B03 secondary 3.J67 3.L80

Estimation methods of eco-environmental water requirements: Case study

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Science china Earth Sciences 2005年第8期48卷 1280-1292页

作者： YANG Zhifeng1,2. CUI Baoshan1 & LIU Jingling 1. School of Environment, beijing Normal University, beijing 100875,{2. 2. State Key Joint Laboratory of Environmental Simulation and Pollution Control, beijing 100875,{2. School of Environment Beijing Normal University Beijing China State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing China

Supplying water to the ecological environment with certain quantity and quality is significant for the protection of diversity and the realization of sustainable development. The conception and connotation of eco-environmental water requirements, including the definition of the conception, the composition and characteristics of eco-environmental water requirements, are evaluated in this paper. The classification and estimation methods of eco-environmental water requirements are then proposed. On the basis of the study on the Huang-Huai-Hai Area, the present water use, the minimum and suitable water requirement are estimated and the cor-responding water shortage is also calculated. According to the interrelated programs, the eco-environmental water requirements in the coming years (2.10, 2.3., 2.50) are estimated. The result indicates that the minimum and suitable eco-environmental water requirements fluc-tuate with the differences of function setting and the referential standard of water resources, and so as the water shortage. Moreover, the study indicates that the minimum eco-environmental water requirement of the study area ranges from 2.84×1010m3.to 1.02.1011m3. the suitable water requirement ranges from 6.45×1010m3.to 1.78×1011m3. the water shortage ranges from 9.1×109m3.to 2.16×1010m3.under the minimum water requirement, and it is from 3.07×1010m3.to 7.53.1010m3.under the suitable water requirement. According to the different values of the water shortage, the water priority can be allocated. The ranges of the eco-environmental water re-quirements in the three coming years (2.10, 2.3., 2.50) are 4.49×1010m3.1.73.1011m3. 5.99×10m3.2.09×1011m3. and 7.44×1010m3.2.52.1011m3. respectively.

关键词： eco-environmental water requirements, assessment methods, Huang-Huai-Hai area.

Wide/narrow azimuth acquisition footprints and their effects on seismic imaging

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Petroleum Science 2008年第4期5卷 308-313页

作者： Di Bangrang Xu Xiucang Wei Jianxin Key Laboratory of CNPC Geophysical Exploration China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Key Laboratory of Earth Prospecting and Information Technology China University of Petroleum Beijing 102249 China

Acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering. At present, the study on acquisition footprints has become a hot spot. In partnership with the Dagang Oilfield, we used the channel sand body seismic physical model to study the characteristics of wide/narrow azimuth acquisition footprints and analyzed and compared the two types of footprints and their effects on target imaging. In addition, the footprints caused by data processing of the normal moveout offset （NMO） stretching aberration were discussed. These footprints are located only in the shallow or middle layer in the time slice, and possibly affect the imaging of shallow target layers, and have no influence on deep target imaging. Seismic physical modeling has its advantages in the study of acquisition footprints.

关键词： Wide/narrow azimuth geometry acquisition footprint stretching aberration time slice seismic imaging

Quasi-secure quantum dialogue using single photons

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2.& WEN QiaoYan3. College of Computer Science and Technology, beijing University of Technology, beijing 10002., china 2.State Key Laboratory of Information Security, Graduate University of the {3. Academy of Sciences, beijing 100049, china 3.School of Science, beijing University of Posts and Telecommunications, beijing 100876, china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of the Chinese Academy of Sciences Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

A new species of Leptocycas (Zamiaceae) from the Upper Triassic sediments of Liaoning Province,china

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Journal of Systematics and Evolution 2010年第4期48卷 286-301页

作者： 1,2.3.ian-Wei ZHANG 2.ian-Xin YAO 1Jia-Rui CHEN 1Cheng-Sen LI 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese Academy of Sciences,{2. 100093.china) 2.State Key Laboratory of Stratigraphy and Paleontology,Institute of Geology,chinese Academy of Geological Sciences,{2. 10003.,china) 3.Graduate University,chinese Academy of Sciences,{2. 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (State Key Laboratory of Stratigraphy and Paleontology Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China) (Graduate University Chinese Academy of Sciences Beijing 100049 China)

A new cycad,Leptocycas yangcaogouensis ***.,was found in sediments from the Late Triassic in western Liaoning,*** pinnately compound leaves(Pseudoctenis type)are screwed in a crown on the stem *** leaflets are linear,with parallel veins and decurrent bases on the *** leaf bases are *** cataphylls intermix with the *** female cone is ovoid in *** characteristics of the new plant are more similar to those of Leptocycas gracilis,a Triassic cycad from North America,but the new species differs from *** in the size of its stem(7–8 vs.3.5 cm in diameter,respectively),leaves(length×width 100×16 vs.3.×7 cm,respectively)and leaf density along the stem(4–6 vs.1–2.bases/1 cm length,respectively).Both *** and ***,having leaves of the Pseudoctenis type,show a closer relationship to the extant Dioon of *** {2. study provides evidence for the origin of the genus Dioon,which may have come from Leptocycas plants of the *** would be assumed that the extent cycads in Zamiaceae originate from the pteridosperms in the Late Paleozoic and have evolved through the stage of *** and *** in Late Triassic,and reaching the extant Dioon.

关键词： china Cycadales Leptocycas Upper Triassic Zamiaceae

Complete multiple round quantum dense coding with quantum logical network

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chinese Science Bulletin 2007年第9期52卷 1162-1165页

作者： LI ChunYan1,2.LI XiHan1,2.DENG FuGuo1,2.3.ZHOU Ping1,2.& ZHOU HongYu1,2.3.1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,{2. Normal University,{2. 100875,china 2.Institute of Low Energy Nuclear Physics,and Department of Material Science and Engineering,{2. Normal University,{2. 100875,china 3.{2. Radiation Center,{2. 100875,china Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing China beijing Radiation Center Beijing China

We present a complete multiple round quantum dense coding scheme for improving the source ca-pacity of that introduced recently by Zhang et al. The receiver resorts to two qubits for storing the four local unitary ope... 详细信息

关键词：量子通信多重量子紧凑编码量子逻辑网络量子纠缠

Population pharmacokinetics of valproate in chinese children with epilepsy

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Acta Pharmacologica Sinica 2007年第10期28卷 1677-1684页

作者： De-chun JIANG~(2.3.,Li WANG~4,Yu-qin WANG~(2.6),Lin LI~3.Wei LU~5,Xiang-rong BAI~2.2.Department of Pharmacy,Xuan-wu Hospital of Capital Medical University,{2. 100053.china ~4 Department of Pediatrics,Peking UniversityFirst Hospital,{2. 10003.,china ~3.Department of Pharmacology,Xuan-wu Hospital of Capital Medical University,Education Ministry KeyLaboratory for Neurodegenerative Diseases,{2. 100053.china ~5 School of Pharmaceutical Science,Peking University,{2. 100083.china Department of Pharmacy Xuan-wu Hospital of Capital Medical University Beijing China Department of Pharmacology Xuan-wu Hospital of Capital Medical University Education Ministry Key Laboratory for Neurodegenerative Diseases Beijing China Department of Pediatrics Peking University First Hospital Beijing China School of Pharmaceutical Science Peking University Beijing China

Aim:The aim of the present study is to establish a population pharmacokinetic（PPK） model of valproate （VPA） in chinese epileptic children to promote thereasonable use of anti-epileptic ***:Sparse data of VPA serumconcentrations from 417 epileptic children were *** patients weredivided into 2.groups:the PPK model group （n={2.7） and the PPK valid group（n=100）.The PPK parameter values of VPA were calculated by NONMEM soft-ware using the data of the PPK model group.A basic model and a final modelwere set *** validate the 2.models,the concentrations of PPK valid groupwere predicted by each model,*** mean prediction error （MPE）,mean squared prediction error （MSPE）,root mean squared prediction error（RMSPE）,weight residues （WRES）,and the 95% confidence intervals （95%CI） were also ***,the values between the 2.models were ***:The PPK of VPA was determined by a 1-compartment model with afirst-order absorption *** basic model was:Ka={2.09 (h-1),V/F=2..4（L）,CL/F=0.2.6 （L/h）.The final model was:Ka=0.2.1+2.2.·（1-HS）(h-1),V/F=2.88+0.157·WT （L）,CL/F=0.1060.98·CO+0.0157·AGE （L/h）.For thebasic model,the MPE,MSPE,RMSPE,WRES,and the 95% CI were-2.2.5{2.-{2..{2.,-16.70）,{2.2..96 （2.72.72.4585.2.）,{2..62.（{2..{2.,44.90）,and-0.06 （-0.14,0.02.,*** the final model,the MPE,MSPE,RMSPE,WRES,and the95% CI were-1.16 （-4.85,2.5{2.,1002.8{2.（1050.64,114{2.61）,2.2.04 （2..12.2..96）,and0.08 （-0.04,0.2.）,*** final model was more optimal than the ***:The PPK model of VPA in chinese epileptic children wassuccessfully *** will be valuable to facilitate individualized dosageregimens.

关键词： population pharmacokinetics valproic acid epilepsy children Bayesian method NONMEM software individualized dosage regimens

On designated-weight Boolean functions with highest algebraic immunity

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Science china Mathematics 2010年第11期53卷 2847-2854页

作者： LIU MeiCheng1,3. DU YuSong2. PEI DingYi2.& LIN DongDai1 1The State Key Laboratory of Information Security, Institute of Software of chinese Academy of Sciences, {2. 100190, china 2.ollege of Mathematics and Information Sciences, Guangzhou University, Guangzhou 510006, china 3.raduate University of chinese Academy of Sciences, {2. 100049, china The State Key Laboratory of Information Security Institute of Software of Chinese Academy of Sciences Beijing China Graduate University of chinese Academy of Sciences Beijing China College of Mathematics and Information Sciences Guangzhou University Guangzhou China

Algebraic immunity has been considered as one of cryptographically significant properties for Boolean functions. In this paper, we study ∑d-1 i=0 (ni)-weight Boolean functions with algebraic immunity achiev-ing the minimum of d and n - d + 1, which is highest for the functions. We present a simpler sufficient and necessary condition for these functions to achieve highest algebraic immunity. In addition, we prove that their algebraic degrees are not less than the maximum of d and n - d + 1, and for d = n1 +2.their nonlinearities equalthe minimum of ∑d-1 i=0 (ni) and ∑ d-1 i=0 (ni). Lastly, we identify two classes of such functions, one having algebraic degree of n or n-1.

关键词： cryptography Boolean function algebraic immunity algebraic degree nonlinearity