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1.
《中国科学院院刊(英文版)》2013,(3):136-136
On July 16,a symposium was convened in Beijing to mark the 20thanniversary of the Xiangshan Science Conferences(XSSC).Under the title of Directions of a New Round of S&T Revolution,the meeting held discussions on S&T development trends in the world and China against the background of globalization.CAS President BAI Chunli,Vice S&T Minister CAO Jianlin and Vice CAS President 相似文献
2.
《中国科学院院刊(英文版)》2003,17(1):52-62
The Endemic Genera of SeedPlants of ChinaThe Endemic Genera of SeedPlants of China is a monographcompiled and written by a group ofresearchers headed by Prof. YingJunsheng (Tsun-shen Ying) of theCAS Institute of Botany. For thefirst time in the world, it gives acomprehensive exposition of theendemic genera of spermatophytes(seed plants) native to China. It de-fines the concept and types of en-demic genera, analyzes theproperties, characteristics, originat-ing dates in geological chroni… 相似文献
3.
Rainfall and air temperature data from six meteorological stations above the Bengbu Sluice and hydrological and water resources evaluation data from the Bengbu Hydrological Station in the Huai River Basin from 1961 to 2008 are used to analyze the impact of changes in climatic factors on the amount of water resources in the Basin. There was a general trend of rise in its average annual air temperature, with the highest increase of 0.289oC/10a recorded at Bengbu in Anhui Province. Rising rainfall was mainly observed in the western part of the study area, while rainfall actually declined in the eastern part, i.e. the middle reaches of the Huai River. The Average rainfall in the study area was in a vaguely declining trend. In other words, the rainfall in the Basin is still much affected by natural fluctuations. On the whole, there was a trend of gradual decrease in the quantity of the Basin’s water resources for the period under study. Water resources quantity is found to fall with decreasing rainfall and rising air temperature. Regression analysis is used to establish a mathematical model between water resources quantity and climatic factors (i.e. air temperature and rainfall) in order to explore the impact of climate change on water resources in the Basin. Moreover, various scenarios are set to quantitatively analyze the response of water resources to climate change. Sensitivity analysis shows that changes in rainfall have a much bigger impact on its water resources quantity than changes in its air temperature. 相似文献
4.
HanJinlin RichardWielebinski 《中国科学院院刊(英文版)》2004,18(2):70-71
The Partner Group does research on cosmic magnetic fields using radio astronomy methods. Magnetic fields are found in every astronomical object: the Earth, the Sun, planets, stars, pulsars, the Milky Way, nearby galaxies and in distant radio galaxies. The role of the magnetic fields in the cosmic universe has not been well investigated, mainly because of the difficulties of their observation. The Partner Group has executed several successful observational projects using the 100m radio telescope in Effelsberg, the Very Large Array in the USA and the Australia Telescope National Facilities to collect polarization data tracing the magnetic fields in the Milky Way. The group further plans to install a 6cm receiver system in a 25m radio telescope in Urumqi next summer to make polarization observations that give an unambiguous picture of magnetic field structures emerging from the disk of the Milky Way. 相似文献
5.
《中国专利与商标》2006,(3)
The Constitution is of supreme legal force. It is a common sense knowledge that any law and administrative regulations contrary to it are not valid legally. To be frank, however, it is an arduous and gradual process to build up a nation under the rule of law. Some typical events or cases often play a tremendous role in laying the foundation of the rule of law in the law-making process in various nations. As a case in point, Marbury v. Madison, a precedent of judicial review, in the 19th century, has contributed greatly to the promotion of the rule of law in the U.S.. In 2003, three Ph.D. scholars wrote to the Standing Committee of the National People's Congress because of the "Sun Zhigang Event", which resulted in the abolishment of the Measures for Housing and Sending Back Tramps/Vagrants and Beggars in Urban Areas. This event will be kept in the history of the governance under the rule of law in China. For this writer, exploration in the issue relating to the validity of duration of patent referred to in the State Intellectual Property Office's (SIPO) Gazette No.80 (hereinafter referred to as Gazette No. 80) involves an issue within the Patent Law, and, as well, of great significance to the entire legal system. These writers hope to clarify the issue of duration of the patent right by exploring the validity of Gazette No. 80. They also hope to promote the amplification of the mechanism for review of unconsttutional actions in China. 相似文献
6.
Jiang Gaoming 《中国科学院院刊(英文版)》2003,17(2):107-115
The frequent occurrence of sandstorms in north China in recent years had an immediatebearing upon the ecological degeneration of grasslands in Inner Mongolia. The long-time preda-tory exploitation of the primordial ecosystems leads to the degradation of the sandy grasslands.In this aspect, human infringement is the predominant reason while natural retrogression issecondary. In the taming of the sandstorm scourge, therefore, the key lies in casting off the live-stock-grazing pressure on the de… 相似文献
7.
《中国科学院院刊(英文版)》2013,(4):198-198
True beauty lies in the sky or in space scientists＇ eyes, in the vast and mysterious space with its order, extent and darkness. They explode with immense power in the solar atmosphere and are hurled out from the Sun at millions of kilometers per hour. They light up brilliant auroras in the mid-latitude skies upon impacting the Earth. Breathtakingly beautiful and yet catastrophically dangerous, they bear a name unfamiliar to the public： coronal mass ejections （CMEs）. 相似文献
8.
《国家科学评论(英文版)》2014,(3)
The ecological water diversion project in the Heihe River Basin is the irst successful case in China in which the ecological systems in a river basin have been rescued. his project serves as a valuable example for the management of ecosystems in other inland river basins. his paper reviews the integrated studies of the water–ecosystem–economy relationship in the Heihe River Basin and concludes that sustainable development in inland river basins requires the basin to be considered as a whole, with the relationships between the upstream, midstream and downstream areas of the basin coordinated appropriately. Successful development in these basins will be relected in an improved output per cubic meter of water and the implementation of integrated river basin management practices. 相似文献
9.
《中国科学院院刊(英文版)》2008,22(1)
Prof.YIN,45,is an electronics expert.He graduated from the Taiyuan Institute of Technology in 1983 and received his Ph.D. in electromagnetic field and microwave technique at the CAS Institute of Electronics(IECAS) in 1995.He took the helm of the IECAS in 1999,and became the director-general of the CAS 相似文献
10.
Innovation, both at past and in the future, is always an everlasting topic in the world, and there is no exception in the educational field. Knowledge economy is featured in the 21st century, while the key of which is the continuous innovation of knowledge. Thus such new talents, with innovation mind and ability, are badly needed. 相似文献
11.
Elsie L. Echeverri-Carroll Michael D. Oden David V. Gibson Evan A. Johnston 《Research Policy》2018,47(1):209-217
There has been considerable media coverage highlighting the lack of gender diversity in Silicon Valley, stressing the relatively low participation of women in the high-tech economy. Austin offers a unique case for testing whether similar gender issues characterized other high-tech regions because the city has historically benefited from the expansion of Silicon Valley’s large high-tech firms since the 1980s. The gender-biased business practices identified in Silicon Valley firms may have been transferred to their branch plants in Austin. Our analysis shows women’s losses in middle-skill occupation employment shares were concentrated in the low-tech industry and were partially offset by job share gains in high-skill occupations in the same sector between 1980 and 2015. Men’s losses in middle-skill occupation job share were also mainly concentrated in the low-tech sector but were partially offset by employment share gains in high-skill occupations only in the high-tech industry during this period. Women made large gains in relative real median wages only in high-skill occupations in the high-tech industry while their relative real median wages in other skill occupations and in the low-tech industry stagnated around zero during this period. Men’s gains in relative median wages were also concentrated only in the high-tech industry but were less than half of women’s and were negative (between ?10 and ?21 percent) in other occupations in the high-tech industry and across all occupations in the low-tech industry. As noted in previous studies, the impact of job polarization is not well understood across sectors and gender. This study finds the high-tech industry in Austin has had unintended consequences in terms of job polarization across gender, providing relatively fewer job opportunities in high-skill occupations to women than men but offering much higher gains in relative real median wages to women than men. Males also found relatively more job opportunities in high-skill occupations in the high-tech industry than women but experienced only half of women’s gains in relative median wages in this industry between 1980 and 2015. 相似文献
12.
R.C. Binder 《Journal of The Franklin Institute》1946,241(2):125-136
An analytical study is presented which explains the cause of one type of surging in a system connected to a fan or compressor. Surging occurs in an unstable region in which the fan pressure rises with an increase in capacity. Surging does not occur in a stable region in which the fan pressure decreases with an increase in capacity. The ratio of vibration pressure amplitude to particle velocity is greater in the unstable region than in the stable region. At critical conditions the pressure wave is in phase with the velocity wave. For a given particle velocity, the pressure amplitude in the unstable region is greater than the pressure amplitude in the stable region. A criterion for no surging is given. 相似文献
13.
论文采用面板数据模型估计了我国制造业集聚的生产率效应,并采用空间俱乐部模型区分了各种效应的地区差别。结果表明,1988-1997年和1998-2009年两个时期,东部和中西部地区均存在显著的静态专业化效应,并且在后期东部的静态专业化效应强于中西部;在整个研究期间,东部和中西部均不存在显著的动态或静态的多样化效应;规模效应在两个时期有所差异,前期在东、中西部均不显著,后期东部存在显著的负向规模效应,而中西部存在正向规模效应,显示出过度集聚开始在东部产生了一定程度的拥塞效应。 相似文献
14.
中国华东及其周边地区NDVI对气温和降水的季节响应 总被引：6，自引：0，他引：6
地表植被与大气的相互作用过程是地球科学领域的研究重点和热点。本文基于SPOTVGT-NDVI数据和气象站点的气温和降水资料,采用时滞相关分析法,研究了1998年-2011年我国华东及其周边地区四季NDVI对气温和降水的时空响应特征。结果表明,在整个研究区,气温对NDVI的影响大于降水,NDVI与气温在夏季和秋季相关性较高,与降水在秋季和春季相关性较高,冬季NDVI与气温和降水相关性都最低。NDVI对气温响应的滞后期在春季和秋季较短,对降水响应的滞后期在冬季较短,夏季NDVI对气温和降水响应的滞后期都较长。在冬季、春季和秋季,NDVI对气温和降水最大相关系数的空间分布在研究区的南北部差异不明显,在夏季则具有较明显的南北差异。NDVI对气温变化响应的滞后期在春季、夏季和秋季具有较明显的南北差异,对降水变化响应的滞后期除在夏季具有一定的南北差异外,在其他季节空间分布规律性不显著。 相似文献
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16.
Vidya Akhileshwar Samir P. Patel Surendra S. Katyare 《Indian journal of clinical biochemistry : IJCB》2007,22(1):84-90
Studies were carried out to examine and compare the effects of alloxan-diabetes on reactive oxygen species (ROS) related parameters
in the heart from male and female rats. Effects of insulin treatment were also evaluated. The diabetic state severely compromised
the ROS defense mechanism in the cardiac tissue and the effects were more pronounced in the female than in the male rats.
There was several fold increase in the xanthine oxidase (XO) activity in general and the magnitude of increase was higher
in the females; insulin treatment resulted in further increase in the XO activity. The glucose-6-phosphate dehydrogenase (G6PDH)
and catalase activities decreased and the reduced glutathione (GSH) content in mitochondria was completely depleted in diabetic
state with significant decrease in the GSH levels in the post-mitochondrial fraction; the effect was more pronounced in the
females. The superoxide dismutase (SOD) and glutathione peroxidase (GPox) activities increased in the diabetic state to a
greater extent in male rats. Insulin treatment had restorative action only on some parameters. In conclusion, our results
suggest that diabetic state may further compromise the weak ROS defense systems in the heart thus initiating a lesion at the
level of mitochondria which ultimately leads to cardiomyopathy and the effects are especially more pronounced in the females.
Our results also pointed out that insulin treatment was ineffective in restoring ROS related parameters. 相似文献
17.
甘肃省能源经济系统分析与优化策略研究 总被引：2，自引：1，他引：1
能源经济系统的优化不仅是实现区域节能减排目标的重要途径,更是社会经济可持续发展的主要内容,本文以甘肃省为研究案例,基于计量经济学方法,对其经济增长与能源消耗之间的动态关系进行了定量研究;进而运用结构分解模型,对比分析了影响单位GDP能耗的主要因素。研究结果表明:甘肃省GDP与能耗总量之间存在长期的协整关系;促进甘肃省能源强度降低的主要因素是各产业能源利用效率的提高,而产业结构变动对全省能源强度降低的贡献份额较小;对能源强度降低贡献较大的为第二产业的效率份额与结构份额,而第三产业结构份额对能源强度降低的贡献为负。文章最后从产业结构优化、关键技术推进、能源结构优化三个角度提出了甘肃省能源经济系统的优化策略。 相似文献
18.
基于可持续度的连云港市土地利用总体规划实施评价 总被引：4，自引：1，他引：3
土地利用总体规划实施评价对于落实规划、强化实施具有重要意义。本文在土地可持续利用研究成果的基础上,通过构建基于可持续度的土地利用总体规划实施评价体系,对连云港市土地利用总体规划实施的可持续度进行了评价。结果表明：①采用可持续度量的方法,可以较好的对土地利用总体规划的实施效果进行定量评价;②上一轮规划实施至今,连云港市土地利用总体规划实施的可持续度呈上升趋势,处于中度可持续状态,但环境指标和社会指标方面,规划实施仍不可持续。在此基础上,提出了新一轮规划着眼解决的3个难题：“生存与发展问题”、“刚性与弹性问题”、“静态与动态问题”,以及完善规划的若干措施和建议,为新一轮规划修编提供有利借鉴。 相似文献
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利用累积湿润指数分析江淮地区农业旱涝时空变化 总被引：23，自引：1，他引：22
提出了一个农业旱涝气象指标一一累积湿润指数。该指标以相对湿润度指数为基础,通过确定不同区域综合农田作物系数对参考作物蒸散量进行订正,并考虑前期旱涝程度对当前旱涝状况的累积影响,从而具有农业意义。用土壤墒情指标对该指标进行分区域旬旱涝等级的确定和检验,其定量符合率为60％-70％,定性符合率为80％．90％。利用该指标分析近30年江淮地区农业旱涝时空变化的结果表明,从多年平均意义上江淮地区农田水分状况能满足作物需求,湿润程度湿润区高于半湿润区。农业旱涝年际变化大,变异率北部大于南部。北部旱涝并存,春旱、夏秋和秋冬连旱频率高,夏季洪涝严重;南部总体湿润,以涝居多,但夏秋干旱频发。在气候变化导致江淮地区降水格局发生变化的条件下,近年来北部夏季洪涝,南部夏秋旱问题突出,值得关注。 相似文献