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β-delayed proton decays near the proton drip line

Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2., CHEN Yongshou 2., XU Furong 3 , WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, china 2. Nuclear Physics Department, china institute of atomic energy, beijing 102.13. china 3. Department of Technical Physics, Peking University, beijing 100871, china 4. Shanghai institute for Nuclear Research, Shanghai 2.1800, china 1. institute of Modern Physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear Physics Department China Institute of Atomic Energy 102413 Beijing China 3. Department of Technical Physics Peking University 100871 Beijing China 4. Shanghai institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2.04, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92.h as well as the predicted “waiting point” nuclei 89Ru and 93Pd are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2. The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142.o and 12.Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3) The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

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The Angular Distribution of Light Composite Particle Projectile in Preequilibrium Reactions

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Chinese journal of nuclear physics 1994年第2期16卷 160-169页

作者： Shen Qingbiao(china institute of {2. energy,P.O.Box 2.5,beijing 102.13. china Inst of atomic {2. Beijing China

Formulations of double differential cross sections of light composite particleconsidering (1,m) and (2.m) pickup type reactions simultaneously for semi-classicalmulti-step compound and direct processes are *** calculated results of crosssections,spectra,and double differential cross sections indicate that generally the con-tributions of the (2.m) pickup type reactions are about 15%-2.% when the incident en-ergies are below 50 MeV but can become dominant when the incident energies areabove 50 MeV in some region of the outgoing energies and *** forward tenden-cy of the calculated angular distributions by (2.m) configuration is weaker than those by(1,m) *** the reactions of outgoing composite particle with higher inci-dent energy,the multi-step direct process must be considered.

关键词： Preequilibrium Composite particle Double differential cross section

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Study for ^(2.8)Th reduction in thermal reactor with Th-U fuel cycls

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Nuclear Science and Techniques 1999年第1期10卷 48-50页

作者： XU Xiaoqin (china institute of {2. energy, beijing 102.1s) china institute of {2. energy Beijing 102413 China

By using computer code WIMS/CENDL, the effects of some parameters, core configuration such as fuel element structure, neutron flux and burn-up, are discussed in this paper. It is shown that high neutron flux, small fuel rod diameter, large volume ratio of coolant to fuel, seed-blank heterogeneous core arrangement and 2.1 Pa chemical separation are necessary for reducing 2.8Th production in reactor.

关键词：热反应堆钍-铀 2.8钍减少

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Effects of Y2.1 phase contents on the critical current density J_c and microstructural analysis in YBCO bulk superconductors

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Rare Metals 2002年第4期21卷 282-288页

作者： SHA Jianjun, YU Gang, and YU Jinnanchina institute of {2. energy, P. O. Box 2.5-51, beijing 102.13. china china institute of {2. energy P.O. Box 275-51 北京 102413

YBCO bulk superconductors were prepared by the solid state reaction andtop-seed-melt-textured growth (TSMTG) process. By using the AC susceptibility measurement, thecritical transition temperature T_c of samples is 91.5 K for the highest value, and the transitionwidth ΔT_c is less than 1 K. The highest magnetization critical current densities J_c achieved 10~6A/cm^2.under 5 T at 10 K and 1.35X10^4 A/cm^2.under 2.T at 70 K (H//c), respectively. The resultscombining the SEM observation indicate that doping of Y2.1 particles is more effective in improvingthe growth quality of melt-textured YBCO superconductor and in reducing the micro-cracks ofspecimens. Doping of Y_2._3 powder forms the rod-shaped Y2.1 particles, but doping of Y2.1 particlesdirectly to matrix materials forms the spherical Y2.1 particles mainly. Combining themicrostructures with J_c measurements shows that the interfaces are most important on flux bundlepinning, in which the gradient of free energy is larger than that of other place between the Y2.1particles and the Y12. matrix materials.

关键词： quasi-single domain melt-textured Y2.1 particles critical current density magnetic flux pinning

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Real-World Treatment Adherence to Smoking Cessation Medications and Association with Treatment Outcome—2. Centers,china,2.17–2.2.

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china CDC weekly 2024年第22期6卷 522-529,I0001-I0003页

作者： Anqi Cheng Zhao Liu Xinmei Zhou Zheng Su Dan Xiao Chen Wang the china National Tobacco Cessation Cohort Study(CNTCCS)Study Group Department of Tobacco Control and Prevention of Respiratory Disease Center of Respiratory MedicineChina-Japan Friendship Hospital/WHO Collaborating Center for Tobacco Cessation and Respiratory Diseases Prevention/National Center for Respiratory Medicine/National Clinical Research Center for Respiratory Diseases/Institute of Respiratory MedicineChinese Academy of Medical SciencesBeijingChina Department of Pulmonary and Critical Care Medicine Center of Respiratory MedicineChina-Japan Friendship Hospital/WHO Collaborating Center for Tobacco Cessation and Respiratory Diseases Prevention/China National Center for Respiratory Medicine/China National Clinical Research Center for Respiratory DiseasesBeijingChina Chinese Academy of Medical Sciences and Peking Union Medical College BeijingChina 不详

What is already known about this topic?Medication non-adherence significantly impedes smoking cessation *** effective smoking cessation medications are accessible in china,realworld adherence and its correlation with treatment outcomes remain largely *** is added by this report?From December 2.17 to January 2.2.,1,12. participants were recruited from 2. centers in all seven geographical regions of *** revealed that only 38.2.of smokers adhered to the prescribed 12.week smoking cessation treatment and those with a higher education level were more likely to be *** addition,smokers with good adherence were more likely to successfully quit *** are the implications for public health practice?The data obtained could enhance our understanding of smoking cessation practices in *** adherence is a crucial strategy to enhance the effectiveness of smoking cessation treatments and management provided to smokers.

关键词： china smoke likely

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Mineralogy and crystal structure determination of Mg-fillowite

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Science china Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2.1. china University of Geosciences, beijing 100083, china 2. institute of Geology, Chinese Academy of Sciences, beijing 10002., china 1. china University of Geosciences 100083 Beijing China 2. institute of Geology Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, china. It is of the trigonal lattice, with space group R-3, unit cell a=1.5143(3) nm, c=4.3191(2. nm, V=8.5736 nm3, Z = 18. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

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Research progress in synthesis and catalysis of polyoxometalates

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Progress in Natural Science:Materials International 2005年第5期15卷 385-394页

作者： GONG Yun1, HU Changwen1* and LIANG Hong2.1. Department of Chemistry, School of Science, the institute for Chemical Physics, beijing institute of Technology, beijing 100081, china 2. Chemical Industry Press, beijing 10002., china) Department of Chemistry School of Science the Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China Chemical Industry Press Beijing 100029 China

Recent progress in the synthetic chemistry and catalysis of polyoxometalates (POMs) is reviewed. The novel POMs and their derivatives emerging in nearly three years (2.02.2.04) are introduced, including POMs with novel structure, POMs-organic hybrid compounds and host-guest complexes. Our review is focused on the elaboration of POMs' supramolecular chemistry.

关键词： polyoxometalates hybrid host-guest structure supramolecule catalysis.

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In situ reproductive organs of Early Cretaceous ferns from Northeast china

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Chinese Science Bulletin 1997年第23期42卷 1977-1980,2026页

作者： DENG Shenghui and CHEN Fen1. Research institute of Petroleum and Development, beijing 100083 2. {2. University of Geosciences, beijing 100083, {2. Research institute of Petroleum and Development Beijing china University of Geosciences Beijing China

FILICOPSIDA is a predominant group of the Early Cretaceous floras of Northeast china, whichapproximates 100 species and accounts for more than one third of the floras. The majority ofthis group are of great importance and significance in stratigraphy. The previous studies ofthese ferns are mainly morphological, with only a few concerning the in situ spores andsporangia. In recent years. the authors have carried out a research project on the in situreproductive organs of the Early Cretaceous ferns from/ basins of Inner Mongolia, Liaoning,Jilin and Heilongjiang of Northeast china. The study focuses on 35 species of 17 genera be-longing to 10 families. The present note briefly introduces the results of this study by listingsome representative species.

关键词： Northeast china Early Cretaceous Filicopsida in situ reproductive organs.

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On three-dimensional geological modeling and visualization

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Science china Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2.1. Department of Resource Exploitation Engineering, china University of Mining and Technology, beijing 100083, china 2. beijing institute of Petrochemical Technology, beijing 102.17, china 1. Department of Resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. beijing institute of Petrochemical Technology 102617 Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

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Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. College of Science, china Agricultural University, beijing 100083, china 2. institute of Physics, Chinese Academy of Sciences, beijing 100080, china 1. College of Science China Agricultural University Beijing 100083 China 2. institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

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