检索结果-南通市图书馆

Heavy ion reactions around the Coulomb barrier

中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 6-13页

作者： ZHANG HuanQiao1, LIN ChengJian1, JIA HuiMing1, ZHANG ChunLei1,2, ZHANG GaoLong1,3, YANG Feng1, LIU ZuHua1, AN GuangPeng1, WU ZhenDong1, XU XinXing1 & JIA Fei1 1 china institute of Atomic energy, P. O. Box 275(10), beijing 1024.3, china 2 Particle Astrophysics Center, institute of high energy physics, chinese academy of Sciences, beijing 100039, china 3 School of physics and Nuclear energy Engineering, Beihang University, beijing 100191, china china institute of Atomic energy Beijing China Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing China School of physics and Nuclear energy Engineering Beihang University Beijing China

The angular distributions of fission fragments for the 32S+184. reaction near Coulomb barrier energies are measured. The ex perimental fission excitation function is obtained. The measured fission cross sections are decomposed into fusion-fission, quasi-fission and fast fission contributions by the dinuclear system (DNS) model. The hindrance to completing fusion both at small and large collision energies is explained. The fusion excitation functions of 32S+90,96Zr in an energy range from above to below the Coulomb barrier are measured and analyzed within a semi-classical model. The obvious effect of positive Q-value multi-neutron transfers on the sub-barrier fusion enhancement is observed in the 32S+96Zr system. In addition, the excitation functions of quasi-elastic scattering at a backward angle have been measured with high precision for the systems of 16O+208Pb, 196Pt, 184., and 154.152Sm at energies well below the Coulomb barrier. Considering the deformed coupling effects, the extracted diffuseness parameters are close to the values extracted from the systematic analysis of elastic and inelastic scattering data. The elastic scattering angular distribution of 17F+12C at 60 MeV is measured and calculated by using the continuum-discretized coupled-channels (CDCC) approach. It is found that the diffuseness parameter of the real part of core-target potential has to be increased by 20% to reproduce the experimental result, which corresponds to an increment of potential depth at the surface re gion. The breakup cross section and the coupling between breakup and elastic scattering are small.

关键词： fusion-fission quasi-fission fusion hindrance fusion enhancement surface diffuseness parameter exotic nuclei

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Formation of super-concentrated hydrochloric acid in the third phase in tertiary amine N235-PtCl_6^(2-)-HCl system and its influences on the Pt microemulsion extraction

引用

Science china Chemistry 2009年第11期52卷 1825-1834页

作者： HUANG Kun1,CHEN Jing1,ZHANG ChengFeng1,2,LI ZhiHong3,PAN QingHua1,SUN Yan1,LIU ShaoXuan1,LIU XueXin2,LI WeiHong1,YANG ZhanLan1,WENG ShiFu1,HU TianDou3,XU YiZhuang1 & WU JinGuang1 1 College of Chemistry and Molecular Engineering,Peking University,beijing 100871,china 2 institute of Chemistry,chinese {4. of Sciences,beijing 100190,china 3 institute of high energy physics,chinese {4. of Sciences,beijing {14.,china College of Chemistry and Molecular Engineering Peking University Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China institute of high energy physics Chinese Academy of Sciences Beijing China

In this paper,we have investigated the formation of the third-phase in tertiary amine(N235)-PtCl62--HCl system and the microscopic phase structural evolution of platinum-loaded organic phases before and after the occurrence of the *** third-phase is characterized by various spectroscopic techniques,and the small angle X-ray scattering(SAXS) experiments demonstrate the appearance of nano-aggregates,i.e.,water-in-oil reversed micelles,in the third *** experimental results indicate that(1) formation of the third phase is related to the aggregation behaviors of nano-reversed micelles in which a super-concentrated hydrochloric acid formed with the H+ to H2O molar ratio being much higher than that of the conventional 37 wt% saturated hydrochloric acid.(2) The occurrence of the super-concentrated HCl results in a great amount of H+ and Cl-ions enriched and confined within the nano-water pools of W/O reversed micelles in third ***,the coordination behaviors of platinum complex ions in that super-concentrated hydrochloric acid are very different from their corresponding behaviors in bulk aqueous *** is possible that H+ ions participate in the formation of such complexes as HmPtCl6z+ in the super-concentrated hydrochloric acid.(3) The relative contents of various HmPtCl6z+ complexes are different corresponding to the H+ ion concentrations in confined nanowater *** association ability of the acidified tertiary amine N235 molecules(R3NH+) with various HmPtCl6z+ complexes plays an important role in affecting the platinum extraction behaviors.

关键词： solvent extraction third phase super-concentrated hydrochloric acid tertiary amine platinum

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The influence of moderate ENSO on summer rainfall in eastern china and its comparison with strong ENSO

引用

chinese Science Bulletin 2008年第5期53卷 791-800页

作者： XUE Feng1 & LIU ChangZheng1,2 1 institute of Atmospheric physics, chinese academy of Sciences, {4. 100029, china 2 Graduate University of chinese academy of Sciences, beijing 10004., china institute of Atmospheric physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China

The 6 major ENSO events since 1979 are classified into the strong and moderate ENSO based on in-tensity. The composite analysis is performed to reveal the influence of ENSO on East Asian summer monsoon (EASM) and summer rainfall in eastern china. It is shown that the influence is changed with the seasonal cycle in summer, with a weaker influence in June and a stronger influence in August, in-dicating a long lagged effect of ENSO on EASM. Besides, the circulation and rainfall anomalies caused by the strong ENSO are also stronger with an earlier starting time, while the influence of the moderate ENSO is evident in August. The composite summer rainfall in eastern china for the moderate ENSO exhibits a northern rainfall pattern, which is totally different from the classical ENSO-type rainfall pat-tern. Based on the composite analysis, two moderate ENSO years with a similar intensity (i.e., 1995 and 2003) are compared. The result shows that, the response of EASM to the moderate ENSO during June and July is, to a certain degree, modulated by the circulation systems in mid-high latitudes of Eurasia and in the Southern Hemisphere, thereby inducing a different rainfall distribution in eastern china. In comparison with the strong ENSO in 1983, it is further revealed that, the strong ENSO plays a dominant role in summer rainfall anomalies in eastern china as well as in controlling the influence of the other factors on EASM. The strong ENSO is therefore different with the moderate ENSO.

关键词：中国东部海洋气象学厄尔尼诺现象东亚季风降雨

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Input function and simulated distributions of tritium in the North Pacific

引用

Science china Earth Sciences 2010年第3期53卷 441-453页

作者： BA Qi1,2 & XU YongFu1 1 State Key Laboratory of Atmospheric Boundary Layer physics and Atmospheric Chemistry, institute of Atmospheric physics, chinese {4. of Sciences, beijing 100029, china 2 Graduate University of chinese {4. of Sciences, beijing 10004., china State Key Laboratory of Atmospheric Boundary Layer physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China

An ocean general circulation model (OGCM) of the North Pacific with a southern open boundary condition is used to simulate the distribution and transport of tritium in the North Pacific. First, the observed tritium in precipitation dataset of GNIP/ISOHIS is chosen, and used to develop an input function of tritium for the model domain from 1951 to 1997 in terms of the triangulation for interpolation. Then, the input function is used as an upper flux for the tritium model. The OGCM with tritium is integrated for 4. years with the initial condition of zero tritium concentrations. Compared with the observations from GEOSECS and WOCE, the model generates a meridional gradient of surface tritium concentrations and the high tritium concentrations in the subsurface layer, which is consistent with that indicated in the observations. The simulated time series of total tritium fluxes from the atmosphere to the ocean shows a spike in 1963. The total inventory of tritium in the ocean changes slowly with time after 1975. Tritium enters the higher-latitude region, and then is mainly transported by the subsurface process towards the equatorial region, which is well simulated in the model. However, the difference mainly occurs at 30°N–4.°N, which can be seen also in the simulation of CFCs. This difference may partly originate from the insufficient description of physical processes in the OGCM. Nevertheless, some uncertainties exist in the development of the tritium input function, which can also influence the simulated results.

关键词： North Pacific basin-wide ocean general circulation model tritium input function tritium distributions

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Bifurcation timescales in power spectra of black hole binaries and ultraluminous X-ray sources

引用

Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 177-182页

作者： WANG TaiShan1 & LI TiPei1,2 1 Department of physics & Center for Astrophysics,Tsinghua University,beijing 100084.china 2 Key Laboratory of Particle Astrophysics,institute of high energy physics,chinese academy of Sciences,beijing 10004.,china Department of physics & Center for Astrophysics Tsinghua University Beijing China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

For black hole binaries(BHBs) and active galactic nuclei(AGNs),bifurcation timescales(BTs) Δtb exist,below which time-domain power is significantly higher than the corresponding Fourier ***-periodic oscillations(QPOs) are removed from the Fourier spectra of BHBs.A relationship between BT,black hole mass and bolometric luminosity is *** anti-correlation between BT and luminosity of Cyg X-1 is *** removing the QPOs,BTs are also obtained for two ultraluminous X-ray sources(ULXs),M82 X-1 and NGC54.8 *** results support that they harbor intermediate mass black holes(IMBHs).

关键词： black hole binary ultraluminous X-ray source power spectral density data analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Diagnostics for the structure of AGNs'broad line regions with reverberation mapping data:confirmation of the two-component broad line region model

引用

Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 196-201页

作者： ZHU Ling1 & ZHANG ShuangNan2 1 Department of physics and Tsinghua Center for Astrophysics,Tsinghua University,beijing 100084.china 2 Key Laboratory of Particle Astrophysics,institute of high energy physics,chinese academy of Sciences,beijing 10004.,china Department of physics and Tsinghua Center for Astrophysics Tsinghua University Beijing China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

We re-examine the ten Reverberation Mapping(RM) sources with public data based on the two-component model of the Broad Line Region(BLR).In fitting their broad Hβ Mlines,six of them only need one Gaussian component,one of them has a double-peak profile,one has an irregular profile,and only two of them need two components,i.e.,a Very Broad Gaussian Component(VBGC) and an Inter-Mediate Gaussian Component(IMGC).The Gaussian components are assumed to come from two distinct regions in the two-component model;they are the Very Broad Line Region(VBLR) and the Inter-Mediate Line region(IMLR).The two sources with a two-component profile are Mrk 509 and NGC *** time lags of the two components of both sources satisfy tIMLR/tVBLR=V 2VBLR/V 2IMLR,where tIMLR and tVBLR are the lags of the two components while VIMLR and VVBLR represent the mean gas velocities of the two regions,supporting the two-component model of the BLR of Active Galactic Nuclei(AGNs).The fact that most of these ten sources only have the VBGC confirms the assumption that RM mainly measures the radius of the VBLR;consequently,the radius obtained from the R-L relationship mainly represents the radius of ***,NGC 4.51,with a lag of about 5 days in the one component model,is an outlier on the R-L relationship as shown in Kaspi et al.(2005);however this problem disappears in our two-component model with lags of about 2 and 6 days for the VBGC and IMGC,respectively.

关键词： broad line region AGN Reverberation Mapping cross correlation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

fMRI time series analysis based on stationary wavelet and spectrum analysis

引用

Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3 , ZHAO Xia~4. SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, institute of high energy physics, {4. academy of Sciences, beijing 10004., china 2. Graduate School of {4. academy of Sciences, beijing 10004., china 3. Department of physics, Zhoukou Normal University, Zhoukou 4.6100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 78229, USA 5. National ASIC Design and Engineering Center, institute of Automation, {4. academy of Sciences, beijing 10004., china 6. Department of physics, Zhejiang University, Hangzhou 310027, china) Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate School of chinese academy of Sciences Beijing 100049 China Department of physics Zhoukou Normal University Zhoukou 466100 China Research Imaging Center University of Texas Health Science Center San Antonio TX 78229 United States National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing 100049 China Department of physics Zhejiang University Hangzhou 310027 China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Challenges in the theoretical investigations of lipid membrane configurations

引用

chinese physics B 2013年第2期22卷 36-44页

作者：涂展春 Department of physics Beijing Normal University Kavli institute for Theoretical physics china Chinese Academy of Sciences

We report some key results in the theoretical investigations of configurations of lipid membranes and present several challenges in this field,which involve（i）the exact solutions to the shape equation of lipid vesicles,（ii）the exact solutions to the governing equations of open lipid membranes,（iii）the neck condition of two-phase vesicles in the budding state,（iv） the nonlocal theory of membrane elasticity,and（v）the relationship between the symmetry and the magnitude of the free energy.

关键词： configuration lipid membrane

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE-Ⅱ SUPERCONDUCTORS

引用

Journal of Computational Mathematics 1997年第4期15卷 365-384页

作者： Zhi-ming Chen (institute of Mathematics, chinese academy of Sciences, beijing,{4.) 中科院数学所北京

In this paper we seek the solutions of the time dependent Ginzburg-Landau model for type-Ⅱ superconductors such that the associated physical observables are spatially periodic with respect to some lattice whose basic lattice cell is not necessarily rectangular. After appropriately foring the gange, the model can be formulated as a system of nonlinear parabolic partial differential equations with quasi-periodic boundary conditions. We first give some results concerning the existence, uniqueness and regularity of solutions and then we propose a semiimplicit finite element scheme solving the system of nonlinear partial dmerential equations and show the optimal error estimates both in the L2 and energy *** also report on some numerical results at the end of the paper.

关键词： Math QT MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE SUPERCONDUCTORS

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dynamics of morphological changes for mitochondrial fission and fusion

引用

Science china(physics,Mechanics & Astronomy) 2010年第4期53卷 680-689页

作者： WANG ShiQi 1,2,4., FU ChangLiang 1,2 , ZHANG Yan 1,2 , CHEN Quan 3 & LONG Mian 1,2 1 Key Laboratory of Microgravity (National Microgravity Laboratory), beijing 100190, china 2 Center for Biomechanics and Bioengineering, institute of Mechanics, chinese {4. of Sciences, beijing 100190, china 3 State Key Laboratory of Biomembrane and Membrane Biotechnology, institute of Zoology, chinese {4. of Sciences, beijing 100101, china 4.institute of Vertebrate Paleontology and Paleoanthropology, chinese {4. of Sciences, beijing 10004., china Key Laboratory of Microgravity (National Microgravity Laboratory) Beijing China Center for Biomechanics and Bioengineering Institute of Mechanics Chinese Academy of Sciences Beijing China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Zoology Chinese Academy of Sciences Beijing China

Mitochondria experience continuous fusion and fission in a living cell, but their dynamics remains poorly quantified. Here a theoretical model was developed, upon a simplified population balance equation (PBE), to predict the morphological changes induced by mitochondrial fission and fusion. Assuming that both fission and fusion events are statistically independent, the survival probability of mitochondria staying in the fission or fusion state was formulated as an exponentially-decayed function with time, which depended on the time-dependent distribution of the mitochondrial volume and the fission and fusion rates. Parametric analysis was done for two typical volume distributions. One was Gamma distribution and the other was Gaussian distribution, derived from the measurements of volume distribution for individual mitochondria in a living cell and purified mitochondria in vitro. The predictions indicated that the survival probability strongly depended on morphological changes of individual mitochondria and was inversely correlated to the fission and fusion rates. This work provided a new insight into quantifying the mitochondrial dynamics via monitoring the evolution of the mitochondrial volume.

关键词： mitochondria morphology fission fusion dynamics modeling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：