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The Contraction of an Isolated Mono-component System

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science China Mathematics 1994年第3期37卷 304-310页

作者： ZHANG Bang-Gu science press Beijing 100717PRC

A mono-component spherical system has been studied under various initial conditions,and an analytic representative p(r=0,t)=p_(0)(1-(D,t)^(2.)of the density at the center of the system has beenfound under the condition that the initial radius of the system r0>Dr The theoretical characteristic constants,the critical radius D^(-1)_(r)=(3kT/4πm^(2.n_(0)G)^(1/2.and the gestation D^(-1)_(r)=(3/4πmn_(0)G)^(1/2.exp(l:2.),are dependent on the initial density p0=mn0t and the initial absolute temperature T at the center of the system These theoretical values accord with the corresponding values of *** results are helpful lor solving the problem of how stars were formed in the universe.

关键词： isolated system critical radius gestation

Focus on polymer chemistry papers in science in China Series B:Chemistry of the year 2.09

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science China Chemistry 2010年第12期53卷 2663-2664页

作者： TIAN Ying science China press,16 Donghuangchenggen North Street,Beijing 100717,China science China press Beijing China

The journal science in China Series B:Chemistry published 11 and 37 papers in polymer fields in 2.08 and 2.09,respectively,leading to a percentage increase of 2.6% and thereby a great historic breakthrough of the *** papers mainly focus on three fields:(1) polymer synthesis,(2. functional polymer materials and (3) biomedical *** research groups published a series of papers in science in China Series B:Chemistry and detailedly introduced their works in the related fields.

关键词： BZ ZK ATRP Focus on polymer chemistry papers in science in China Series B PDMAEMA

Report:How many Chinese journals are included in the newly indexed 700 regional journals on Web of science?

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2008年第7期9卷 1011-1014页

作者： Xiu-fang WU Qiang FU Helen （Yue-hong） ZHANG Journals of Zhejiang University SCIENCE （A ＆B） Zhejiang University Press Hangzhou 31002 7 China Zhejiang University press Hangzhou 310028 China

Based on the current news via Thomson Reuters "700 new regional journals in the world have been added to Web of science since 2.07",we conducted an investigation to find out that 43(6.1%) Chinese journals(including 6 journals from Hong Kong region) are included. The results also show that up to now a total of about 153 Chinese journals(114 from China Mainland,11 from Hong Kong and 2. from Taiwan) have been included by SCI and SSCI & AHCI.

关键词： CLC numberG2. G354

Should the K-Ar isotopic ages of olivine basalt be reconsidered?

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Chinese science Bulletin 1998年第19期43卷 1670-1671页

作者： Ren, Shengli science in China press Beijing China

Has the cardiac stem cell controversy settled down?

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science China(Life sciences) 2014年第9期57卷 949-950页

作者： WU MingFu MENG FanXia Cardiovascular science Center Albany Medical College science China press

Although the human adult heart was considered a terminally differentiated organ and incapable of renewal after injury or with aging for almost a century, recent studies have shown that the heart is capable of new cardiomyocyte formation and possesses varying degrees of regenerative potential throughout mammalian life. However, whether the cardiac stem cells （CSC） or the pre-existing cardiomyocytes con- tribute to the new cardiomyocyte formation remains con- troversial.

关键词：干细胞心脏心肌细胞终末分化哺乳动物 CSC

Development of science China Chemistry during 2.08-2.12.From the perspective of Special Issues/Topics

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science China Chemistry 2012年第12期55卷 2617-2626页

作者： SONG GuanQun ZHU XiaoWen science China press 16 Donghuangchenggen North StreetBeijing 100717China

1 Introductionscience China press Co., Ltd. （SCP） is a science and technology （ST） journal publishing company of the Chinese Academy of sciences （CAS）. SCP publishes 16 kinds of academic journals,

关键词： Chemistry Synthesis (chemical)

Density functional theory analysis of electronic structure and optical properties of La-doped Cd_2.nO_4 transparent conducting oxide

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Chinese Physics B 2018年第1期27卷 486-491页

作者：汤梅尚家香张跃 School of Materials science & Engineering Beihang University Journal Publishing Center of Tsinghua University press

The electronic structural, effective masses of carriers, and optical properties of pure and La-doped Cd2.nO4 are calculated by using the first-principles method based on the density functional theory. Using the GGA＋U method, we show that Cd2.nO4 is a direct band-gap semiconductor with a band gap of 2.2.6 eV, the band gap decreases to 2.02.eV and the Fermi energy level moves to the conduction band after La doping. The density of states of Cd2.nO4 shows that the bottom of the conduction band is composed of Cd 5s, Sn 5s, and Sn 5p orbits, the top of the valence band is composed of Cd 4d and O 2., and the La 5d orbital is hybridized with the O 2. orbital, which plays a key role at the conduction band bottom after La doping. The effective masses at the conduction band bottom of pure and La-doped Cd2.nO4 are 0.18m0 and 0.092.0, respectively, which indicates that the electrical conductivity of Cd2.nO4 after La doping is improved. The calculated optical properties show that the optical transmittance of La-doped Cd2.nO4 is 92., the optical absorption edge is slightly blue shifted, and the optical band gap is increased to 3.2.3 eV. All the results indicate that the conductivity and optical transmittance of Cd2.nO4 can be improved by doping La.

关键词： transparent conducting oxides electronic band structure first-principle calculations optical prop-erties

DEVELOPMENT OF ATMOSPHERIC CIRCULATION AND IRREGULARITY OF EARTH

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science in China,Ser.B 1982年第5期25卷 531-546页

作者：彭公炳陆巍 Institute of Geography Academia Sinica science press

In this paper, a study has been done on the interaction between the development ofatmospheric circulation and the irregularity of the earth rotation; relevant equations havebeen developed to show the probable variations of the earth’s crust and atmospheric move-ment in the event that the earth rotation changes in velocity; some discussion has beenmade about the probable variations of the direction of atmospheric movement. To verifythe aforesaid considerations and equations, a number of circulation and weather-climate factsin connection with the changes of the earth rotation velocity are presented.

关键词： DEVELOPMENT OF ATMOSPHERIC CIRCULATION AND IRREGULARITY OF EARTH

Some new results of electric power science

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science China(Technological sciences) 2011年第7期54卷 1940-1942页

作者： AN Mei science China press 16 Donghuangchenggen North Street Beijing 100717 China

At present, one of the most important demands in the world is energy. And improvement of technology and management can increase energy efficiency [1]. Compared with coal and oil, electricity is a kind of clean and efficient secondary energy. The development of the electric power science is essential for the human world and its new results are also remarkable. A modem power system has a very complex control structure, and is generally composed of hundreds of thousands of components. Consequently, it is very difficult and arduous to control and manage a modem power system to make it reliably and securely provide high quality yet economic power supply.

关键词： Algorithms Electric power distribution Energy management Linear matrix inequalities Lyapunov functions Number theory