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1.
《中国科学院院刊(英文版)》2018,(1)
正Big Bang Nucleosynthesis(BBN)has produced three light elements:hydrogen,nitrogen and lithium.Measuring the abundances of these elements is the most reliable way to explore the physical condition in the first few seconds after the BBN.Recently,using LAMOST data and follow-up observations,the stellar abundance group at the National Astronomical Observatories of the Chinese Academy 相似文献
2.
XML的显示 总被引：2，自引：0，他引：2
Tbe eXtensible Markup Language(XML)describes a document's structure and content, not the style of the elements on the page. The style can be added to a document with a style sheet. Both Cascading Style Sheet(CSS)and eXtensible Style Languange(XSL)can produce such a style sheet. The HyperText Markup Language(HTML) provides a markup that looks like < xml > , by which XML document can be easily bound to some HTML elements. 相似文献
3.
Abstract.The Silk Road is one of the most important cultural routes in human being history and it had survived abundant cultural heritages.Under the vision of culture integrity,the constitution of the Silk Road(Shaanxi section)heritage corridor should involve tangible and intangible heritage elements.It is necessary to recognize the relationship between tangible and intangible culture heritages in order to realize the reasonable conservation of the Silk Road. 相似文献
4.
《中国科学院院刊(英文版)》2019,(3)
<正>In the early 20~(th) century,thanks to improved precision of ionization measurement,atmospheric ionization was widely observed and attributed to high-energy radiations generated by the decay of radioactive elements on the Earth.From 1911 to 1913,by carrying out a series of high-altitude balloon experiments,Austrian physicist Victor Franz Hess discovered high-energy radiations 相似文献
5.
IA应用研究--我国政府网站考察与评价 总被引：20，自引：0，他引：20
Issuing government information is a major task of the government Website. So it‘‘s important that the government Website is organized in accordance with the users‘‘ need and habit. In this article, the theory of Information Architecture (IA) is used to examine and evaluate some government Websites in an attempt to investigate some elements of government Websites such as the navigation system, information retrieval method and ways of information organizing and labeling. 相似文献
6.
The development of modern science and technology requires high magnetic fields exceeding 25 T.Second-generation high-temperature superconducting wires,i.e.REBCO(REBa2Cu3O7-x,RE refers to Y,Gd,Dy,Eu and other rare-earth elements) coated conductors(CCs),have become the first choice for high-field magnet construction because of their high irreversible magnetic field.The mechanical stresses caused by manufacturing,thermal mismatch and Lorenz forces closely influence ... 相似文献
7.
The metallogeny of the dispersed elements and lowtemperature deposits in China, predominantly distributed in the Southwest China, is quite unique and special in the global geological background. On the basis of the special geological settings of the Southwest China,this project has carried out a pioneering and comprehensive research on the metallogeny of the dispersed elements and low-temperature deposits in China by applying closely integrated methods of the geology and geochemistry of mineral deposits, experimental simulation and computing simulation. In this way, it has achieved the following research results: 相似文献
8.
构筑信息服务保障体系思实录 总被引：2，自引：0，他引：2
Combining theory with practice and proceeding from operability, this paper puts forward 7 principles of con-structing the information service guarantee system, that is, engineering, capability, mutual service, service advantages,Web-besed information, overall coordination and sustained perfection. Meanwhile, the paper poirts out that, in the con-stmcfion and operation of the information service guarantee system, the interrelationship of key elements is more important than the constitution of key elements, and the construction of the system is more important than the application of technology. 相似文献
9.
Climate change will lead to a signifi cant alteration in the temporal and spatial pattern variation in the regional hydrological cycle, and the subsequent lack of water, environmental deterioration, floods and droughts etc. And it is especially remarkable in semi-humid and semi-arid region. In this paper, the impacts of climate change on the hydrological cycle were analyzed for the Hai River Basin, a semi-humid and semi-arid basin and also the water receiving area of the middle route of South-to-North Water Diversion Project. Meanwhile it is the most vulnerable to climate change. Firstly, the linear regression and Mann-Kendall non-parametric test methods were used to analyze the change characteristics of the hydrological and meteorological elements for the period from 1960 to 2009. The results show a signifi cant increase in temperature, while precipitation decreases slightly, and runoff decreases drastically over the past 50 years. Secondly, the applicability of SWAT (Soil and Water Assessment Tool) model based on the DEM (Digital Elevation Model), land use and soil type was verif ied in the basin. Results show the model performs well in this basin. Furthermore, the water balance model, Fu’s theory and Koichiro’s theory were used to calculate the actual evaporation, comparing to the simulated actual evaporation by SWAT model to validate the result for the lack of large-scale observed evaporation datasets. Possible reasons were also analyzed to explore the reasonable factor for the decline of the runoff. Finally the precipitation, temperature, runoff and evaporation response processes based on the IPCC AR4 multi-mode climate models and the verifi ed SWAT model under different GHG emission scenarios (SRES-A2, A1B and B1) in the 21st century were discussed in three time periods: 2020s (2011-2040), 2050s (2041-2070), 2080s (2071-2099). Results show that there are systematic positive trends for precipitation and temperature while the trends for runoff and evaporation will differ among sub-areas. The results will offer some references for adaptive water management in a changing environment, also including adaptation of a cross-basin water transfer project. 相似文献
10.
YUE Lin YAN Wenjun Graduate University of the Chinese Academy of Sciences Beijing 《中国科学院院刊(英文版)》2011,(4)
On May 26 and 27, 2011, the 2nd Sino-US S&T Strategic Policies Meeting and Workshop on Managing Intellectual Property (IP) was held in Beijing. Jointly organized by the Chinese Academy of Sciences (CAS), the Chinese Academy of Engineering (CAE), the US National Academy of Science (NAS) and the US National Academy of Engineering (NAE), the meeting & workshop was hosted by the CAS Bureau 相似文献
11.
《中国科学院院刊(英文版)》2006,20(2):116-119
The Academy of Opto-Electronics (AOE) is an institution under the direct jurisdiction of the CAS headquarters. Organizationally, it has six components: the head office, the Changchun Institute of Optics, Fine Mechanics & Physics (CIOMP), the Shanghai Institute of Technical Physics (SITP), the Xi’an Institute of Optics & Precision Mechanics (XIOM), the Shanghai Institute of Optics & Fine Me- chanics (SIOM) and the Institute of Optics & Electron- ics (IOE) in Chengdu. The p… 相似文献
12.
On April CAS BHP-Billiton a Melbourne-based company of diversified resources held a special workshop on cooperation in Beijing.…… 《中国科学院院刊(英文版)》2007,21(3):172-172
Under the joint sponsorship of the Shanghai Institutes for Biological Sciences (SIBS) and Swiss Federal Institute of Technology (ETH Zurich), the Shanghai Center for Cassava Biotechnology (SCCB) has been established at the Shanghai Institute of Plant Physiology and Ecology(SIPE), SIBS. 相似文献
13.
The sexual harassment to women often happen in the China society, but the ways of civil relieving for women who have been harassed are few. Besides the factor of ancient culture, lack deep researching and comprehensive legal system safeguards about women right, sluggish justice＇s feedback against sexual harassment are mental elements for this difficult position. 相似文献
14.
<正>After eons of evolution,biological systems have developed excellent performance in terms of sensing,intelligence,and actuation—the three primary robotics elements that are closely related to the overall performance of robot systems.For example,the buccal pits of some snakes,as the necessary sensors for accurate predation,have a high-temperature sensitivity of 0.003 K[1]; 相似文献
15.
Abstract Knowledge management （KM） has been receiving considerable attention in the human-system research community. And it is one of the key issues on what the cognitive structure （schema） is and how it transfers. From different perspectives, such as the cognitive science, the concepts, elements and characteristics of cognitive schema, the knowledge structure, knowledge acquisition and influence of schema on it, this paper explores the cognitive schema of knowledge management. 相似文献
16.
Carbon energy has contributed to the creation of human civilization,and it can be considered that the configuration of the carbon energy system is one of the important laws that govern the operation of everything in the universe.The core of the carbon energy system is the opposition and unity of two aspects:oxidation and reduction.The operation of oxidation and reduction is based on the ternary elemental system composed of the three elements of carbon,hydrogen and oxygen.Its operation produces n... 相似文献
17.
On the eve of the 11th General Assembly of the Chinese Academy of Sciences (CAS), the CAS Presidium briefed the press on the important advances achieved by the Academic Divisions (ADs) over the past two years. 相似文献
18.
Xizang (Tibet) is rich in Leguminosae flora, comprising 41 genera and 254 species
so far known, exclusive of the commonly cultivated taxa (including 11 genera and 16
species). There are 4 endemic genera (with 8 species), 10 temperate genera (with 175
species) and 19 tropical genera (with 46 species) as well as the representatives of those
genera whose distribution centers are in East Asia-North America, Mediterranean
and Central Asia.
1. There are altogether 4 endemic genera of Leguminosae in this region. Accord-
ing to their morphological characters, systematic position and geographical distribution,
it would appear that Salweenia and Piptanthus are Tertiary paleo-endemics, while
Straceya and Cochlianths are neo-endemics. Salweenia and Piptanthus may be some
of more primitive members in the subfamily Papilionasae and their allies are largely
distributed in the southern Hemisphere. The other two genera might have been derived
from the northern temperate genus Hedysarum and the East Asian-North American
genus Apios respectively, because of their morphological resemblance. They probably
came into existanc during the uplifting of the Himalayas.
2. An analysis of temperate genera
There are twelve temperate genera of Leguminosae in the region, of which the
more important elements in composition of flora, is Astragalus, Oxytropis and Cara-
gana.
Astragalus is a cosmopolitan genus comprising 2000 species, with its center
distribution in Central Asia. 250 species, are from China so far known, in alpine zone of
Southwest and Northwest, with 70 species extending farther to the Himalayas and
Xizang Plateau.
Among them, there are 7 species (10%) common to Central Asia, 12 species (15.7%)
to Southwest China and 40 species (60%) are endemic, it indicates that the differentia-
tion of the species of the genus in the region is very active, especially in the subgenus
Pogonophace with beards in stigma. 27 species amounting to 78.5% of the total species of
the subgenus, are distributed in this region. The species in the region mainly occur in
alpine zone between altitude of 3500—300 m. above sea-level. They have developed into
a member of representative of arid and cold alpine regions.
The endemic species of Astragalus in Xizang might be formed by specialization of
the alien and native elements. It will be proved by a series of horizontal and vertical vicarism of endemic species. For example, Astragalus bomiensis and A. englerianus are
horizontal and vertical vicarism species, the former being distributed in southeast part
of Xizang and the latter in Yunnan; also A. arnoldii and A. chomutovii, the former
being an endemic on Xizang Plateau and latter in Central Asia.
The genus Oxytropis comprises 300 species which are mainly distributed in the
north temperate zone. About 100 species are from China so far known, with 40 species
extending to Himalayas and Xizang Plateau. The distribution, formation and differ-
entiation of the genus in this region are resembled to Astragalus. These two genera are
usually growing together, composing the main accompanying elements of alpine mea-
dow and steppe.
Caragana is an endemic genus in Eurasian temperate zone and one of constructive
elements of alpine bush-wood. About 100 species are from China, with 16 species in Xi-
zang. According to the elements of composition, 4 species are common to Inner Mon-
golia and Kausu, 4 species to Southwest of China, the others are endemic. This not only
indicates that the species of Caragana in Xizang is closely related to those species of
above mentioned regions, but the differentiation of the genus in the region is obviously
effected by the uplifting of Himalayas, thus leading to the formations of endemic species
reaching up to 50%.
3. An Analysis of Tropical Genera
There are 19 tropical genera in the region. They concentrate in southeast of Xizang
and southern flank of the Himalayas. All of them but Indigofera and Desmodium are
represented by a few species, especially the endemic species. Thus, it can be seen that
they are less differentiated than the temperate genera.
However, the genus Desmodium which extends from tropical southeast and northeast
Asia to Mexio is more active in differentiation than the other genera. According to Oha-
Shi,s system about the genus in 1973, the species of Desmodium distributed in Sino-Hima-
laya region mostly belong to the subgenus Dollinera and subgenus Podocarpium. The
subgenus Dollinera concentrates in both Sino-Himalaya region and Indo-China with 14
species, of which 7 species are endemic in Sino-Himalaya. They are closely related to
species of Indo-China, southern Yunnan and Assam and shows tha tthey have close con-
nections in origin and that the former might be derived from the latter.
Another subgenus extending from subtropical to temperate zone is Podocarpium.
Five out of the total eight species belonging to the subgenus are distributed in Sino-
Himalaya and three of them are endemic.
An investigation on interspecific evolutionary relationship and geographic distribu-
tion of the subgenus shows that the primary center of differentiation of Podocarpium
is in the Sino-Himalaya region.
Finally, our survey shows that owing to the uplifting of the Himalayas which has
brought about complicated geographic and climatic situations, the favorable conditions
have been provided not only for the formation of the species but also for the genus in cer-tain degree. 相似文献
19.
On May 26 and 27, 2011, the 2nd Sino-US S&T Strategic Policies Meeting and Workshop on Managing Intellectual Property (IP) was held in Beijing.Jointly organized by the Chinese Academy of Sciences (CAS), the Chinese Academy of Engineering (CAE), the US National Academy of Science (NAS) and the US National Academy of Engineering (NAE), the meeting & workshop was hosted by the CAS Bureau of International Cooperation and the CAS Graduate University.It provided an opportunity for both sides to exchange views on S&T strategic policies, especially laws, regulations, measurements and practices on intellectual property management.This was the first time that the meeting & workshop comes to China after the first session of such a meeting & workshop was held in US in 2009. 相似文献
20.
《中国科学院院刊(英文版)》2019,(4)
<正>The predentary bone is one of the most enigmatic skeletal elements in avian evolution. Located at the tip of the lower jaw, this bone is absent in more primitive birds and in living birds; it is thought to have been lost during evolution. For over 30 years the origin and function of the avian predentary has remained mysterious. Now, however, Alida Bailleul, LI Zhiheng, Jingmai O'Connor and ZHOU Zhonghe from the Institute of 相似文献