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1.
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   

2.
AYangtze finless porpoise was born on July 5 at the CAS Institute of Hydro- biology (IHB) in Wuhan, capital of central China’s Hubei Province. This is the world’s first successful breeding of such an animal in an artificial environment. The feat will contribute to the ex situ conserva- tion of this endangered species. Th e fi n l es s p or p o i s e (Neophocaena phocaenoides) is one of the smallest cetaceans in the world. They have three distinct subspecies, and the Yangtze finless po…  相似文献   

3.
<正>Noise-induced hearing loss (NIHL) is one of the most common types of hearing loss and contributes to significant morbidity worldwide,as well as being the major cause of age-related hearing loss and tinnitus.The World Health Organization (WHO) estimates that 10%of the world’s population is exposed to sound levels that could potentially cause NIHL[1].It has been widely accepted that NIHL is a multifactorial genetic disorder with estimated heritability of 36%to 40%[2].Ideally,identificatio...  相似文献   

4.
It is widely acknowledged that the ultimate goal of tea- ching is to help students acquire subject-matter knowledge. But accordingtoRichard E. Mayer(2003)“,apassage may be difficult to comprehend when the reader lacks an appropriate perspective or has a perspective different from that of a writ- er.”. In this sense, the teaching of learning strategies seems important in teaching process. For example, my teaching tar- gets are college students, they are often confronted with such dilemma: th…  相似文献   

5.
<正>The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].  相似文献   

6.
The purpose of this paper is to discuss the influence of sampling rate on closed system which has been discretized from continuous system and in which the ZOH is not inserted, As an example, in has been discribed for the second order system that the impoper choice of sampling rate may cause the unstability of a discretized system, though its original continuous system is stable. The change of locations of poles due to the variations of sampling rate are shown in plots. Proper sampling rate is suggested. Different methods of discretization are compared, and the bilinear transform is recommended.  相似文献   

7.
The ultimate objective of the inertial confinement fusion (ICF) research is to achieve the realization of controllable nuclear fusion, a kind of subatomic reactions, in which the union of lighter atomic nuclei forms heavier ones in company with release of an enormous amount of energy, in hope of solving the increasingly urgent issue of energy shortage in human society. Acting as an important experimental platform for the short-term and mid-term ICF studies in China, the Shenguang (Divine Light)-Ⅱ laser facility (SG-Ⅱ) is the largest facility ever developed in this country and listed among the few high-performance and huge-power solid-state laser drivers in the world today.  相似文献   

8.
Environmental change is a consequence of many interrelated factors.How vegetation responds to natural and human activity still needs to be well establishe d,quantified and understood.Re cent satellite missions providing hydrologic and ecological indicators enable better monitoring of Earth system changes,yet there is no automatic way to address this issue directly from observations.Here,we develop an observation-based methodology to capture evidence of changes in global terrestrial ecosystems an...  相似文献   

9.
The CAS Academic Divisions (CASAD) is es-tablished on June 1, 1955. At present, it has sixdivisions of mathematics & physics, chemistry,life sciences & medical sciences, earth sciences, in-formation sciences and technical sciences. In 1984,the State Council defined its principal function inclear terms, i.e. “the highest advisory body of theState in science and technology” while the CAS mem-bership is “the highest academic title conferred bythe State to an individual in the fields of …  相似文献   

10.
The end-Permian mass extinction is the greatest bioevent in the geological history, which wiped out nearly 95% of the marine species and 75% of the terrestrial species,followed by a biological winter for more than five million years.The cause and the process of the end-Permian mass extinction remain an unsolved mystery in earth science and one of the most difficult and interesting scientific problems.  相似文献   

11.
This paper is the documentation of specimens and literature reffered to Atracty- lodes lancea (Thunb.) DC. etc. As a result, it is found that, in taxonomy of the genus Atractylodes, what represcents by four long-established names, i. e. Atractylodes lancea (Thunb.) DC., A. ovata (Thunb.) DC., A. chinensis (Bunge) Koidz. and A. lyrata Sieb. et Zucc., in fact, is the one and same species.  According to the law of priority in nomenclature, the first name should be given to Chinese drug “Cangzhu”, while theother three names have to be treated as its synonyms.  相似文献   

12.
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   

13.
Understanding changes in pathogen behavior(e.g.increased virulence,a shift in transmission channel) is critical for the public health management of emerging infectious diseases.Genome degradation via gene depletion or inactivation is recognized as a pathoadaptive feature of the pathogen evolving with the host.However,little is known about the exact role of genome degradation in affecting pathogenic behavior,and the underlying molecular detail has yet to be examined.Using large-scale global avian...  相似文献   

14.
I. Significance of Right of Priority The doctrine of right of priority, originating from the Paris Convention for the Protection of Industrial Property, and purporting to facilitate application for patents and trademarks in different countries, means that when an applicant files, within a given time limit after filing an application in a member state of the Paris Convention, another application in respect of the same subject matter in another member state, he/it may take the date of filing of the first application as the date of filing of the later application (referred to as the date of priority). The basis on which a foreign right of priority is established lies in that most countries adopt the first-to-file doctrine in patent grant. That is, it is presumed under the law that a person who first files an application is one who first accomplishes the in-  相似文献   

15.
大众传播信息合理使用原则分析   总被引:1,自引:0,他引:1  
The principle of the rational use of the copyright of mass communication is an importamt legal system to protect the right of the social public and individuals to use information. However, this system is facing severe challenges both in technology and in benefit. This paper attempts to analyzes the problems in the principle of rational use, such as the principle of judgement, abuse restriction and the principle of rational use under the network communication conditions.  相似文献   

16.
The trademark having the nature of fraud refers to a word/device constituting a trademark that is confusing e-nough to mislead the average consumers as to the quality, raw material, function, use, weight, quantity, and place of o-rigin of a product. Article 10, paragraph one (7) of the Trademark Law prohibits those having the nature of exaggeration and fraud from being used as trademarks. Evidently, "exaggerating" advertisement is not the only cause of trademark having the nature of fraud. With an analysis of two  相似文献   

17.
<正>Researchers from the State Key Laboratory of Space Weather,National Space Science Center(NSSC)have recently reported a puzzling phenomenon of geospace magnetic field changes in response to interplanetary shocks.Contrary to the intuitive view that compressions brought about by interplanetary shocks always lead to an increase of  相似文献   

18.
<正>Outer space is the fourth territory for human beings in addition to the land,ocean and airspace.It was pointed out by Albert Einstein many years ago that science in the future might proceed in two different directions,i.e.,towards either the microscopic world or the macroscopic world.These are exactly what space science is concerned with.On the cosmological scale,space science studies the universe.On the microscopic scale,space science studies the existence of dark matter,the basic laws of atoms and cells under extreme conditions and variable gravity in space.Therefore,space science is at the forefront of science in that it covers  相似文献   

19.
20.
利用△R(n)/△n界定核心区域的探讨   总被引:2,自引:0,他引:2  
Based on R (n) - n curve, this article makes a deep analysis of △R (n) /△n from the mathematical,geometrical and actual meanings. The change of △R (n) /△n indicates that there is a clear convergence and dispersion inthe actual distribution of the documents of the journals. The area in which △R (n) /△n changes greatly is the core area,the area in which △R (n) /△n changes continuously is the dispersive area, and the point at which the variance of △R (n) /△n is bigger than 1 for the two adjacent journals may be taken as the boundary line between the core area and the non-core area.  相似文献   

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