检索结果-南通市图书馆

status of two Coreius species in the Three Gorges Reservoir,China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Oceanology and Limnology 2016年第1期34卷 19-33页

作者：夏雨果 J.LLORET 李钟杰张堂林叶少文李为苑晶 H.A.C.C.PERERA 刘家寿 State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China Faculty of Sciences Campus MontiliviUniversity ofGirona17071 Girona(Catalonia)Spain

Dam construction alters natural flow regimes which,in turn,cause significant changes in fish communities during and after impoundment. The construction of the Three Gorges Reservoir,from impoundment of the Changjiang(Yangtze) River,China,may have affected native fish species. Thus,the status of two lotic freshwater fish species,Coreius heterodon and ***,were monitored in the Three Gorges Reservoir,including fish abundance,individual composition,growth,condition,and mortality. Data on both species were gathered from upstream,midstream and downstream areas of the reservoir and,where available,from studies published before and after dam construction. Lower abundance,slower growth,a less diversified age structure,poorer fish condition(indicated by hepatosomatic index) and higher mortalities were recorded in sites nearest the dam compared with upstream areas. Furthermore,after final impoundment,individual Coreius species inhabiting the area changed,with young individuals becoming more abundant,while upstream of the reservoir the two Coreius species became smaller at a given age. The results show that the status of the two Coreius species was subject to dramatic changes after impoundment.

关键词： Three Gorges Reservoir Coreius species status age profile growth impoundment

status of Stratigraphy Research in China

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2016年第4期90卷 1069-1081页

作者： YAO Jianxin BO Jingfang HOU Hongfei WANG Zejiu MA Xiulan LIU Fengshan HU Guangxiao JI Zhansheng WU Guichun WU Zhenjie LI Suping GUO Caiqing LI Ya Key Laboratory of Stratigraphy and Paleontology Ministry of Land and Resources Institute of GeologyChinese Academy of Geological Sciences Beijing 100037 China Chinese Academy of Geological Sciences Beijing 100037 China China Geological Survey Beijing 100037 China

Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy （ICS）. Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points （GSSPs） for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart （ICC）, 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for strafigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the ＂Regional Chronostratigraphic Chart of China （geologic time）＂, in which 59 stages were studied in depth. In 2014, the ＂Stratigraphic Chart of China＂ was compiled, with the essential contents as follows： the correlation between international chronostratigraphy and regional chronostratigraphy of China （geologic time）, the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage.

关键词： Stratigraphy research process status China.

status of Rare Earths for Agriculture in China

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2004年第z1期22卷 313-316页

作者： Wang Jiachen Yang Jun Liu Xiangsheng Beijing General Research Instiutes for Nonferrous Metals Beijing 100088 China National Rare Earth Center for Agriculture of China Beijing 100088 China Grirem Advanced Materials Co.Ltd. Beijing100088 China

Rare Earths (RE) for agriculture is a very typical application and has already brought good economic benefit to Chinese agriculture and *** this paper, the origin, development, status and the future of RE for agriculture in China were ***, through the researches of RE in the fields of physiological activity, physiological and biochemical mechanism, sanitation toxicology and environment security in 1980's, RE has been extended more widely in agriculture, such as crops, vegetables, forest, wood grass and stock breeding, such as cattle, fish and ***, with using of new techniques that were developed in the "State Ninth Five-Year Plan", the utilization area of RE was expanded to broad agricultural space, such as sunlight converting plastic film, RE fertilizer, RE drought resistant and RE water saving materials and new RE top dressing ***, with the development of the nanometer materials, the techniques and process of nanometer RE materials were *** these kinds of materials, the new seed cover matters, new seed mixed matter and new nanometer fertilizer will appear in the near future, and will produce many updated techniques and improve a new round RE application in agriculture.

关键词： agriculture typical application origin development status

A reliability evaluation method for embryonic cellular array based on Markov status graph model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2020年第2期31卷 432-446页

作者： WANG Tao CAI Jinyan MENG Yafeng ZHU Sai Department of Electronic and Optical Engineering Army Engineering UniversityShijiazhuang 050003China

Due to the limitations of the existing fault detection methods in the embryonic cellular array(ECA), the fault detection coverage cannot reach 100%. In order to evaluate the reliability of the ECA more accurately, embryonic cell and its input and output(I/O) resources are considered as a whole, named functional unit(FU). The FU fault detection coverage parameter is introduced to ECA reliability analysis, and a new ECA reliability evaluation method based on the Markov status graph model is *** experiment results indicate that the proposed ECA reliability evaluation method can evaluate the ECA reliability more effectively and accurately. Based on the proposed reliability evaluation method, the influence of parameters change on the ECA reliability is studied, and simulation experiment results show that ECA reliability can be improved by increasing the FU fault detection coverage and reducing the FU failure rate. In addition, by increasing the scale of the ECA, the reliability increases to the maximum first, and then it will decrease continuously. ECA reliability variation rules can not only provide theoretical guidance for the ECA optimization design, but also point out the direction for further research.

关键词： embryonic Markov status graph model reliability fault detection evaluation

Synchronous detection of glutathione/hydrogen peroxide for monitoring redox status in vivo with a ratiometric upconverting nanoprobe

在线全文

学校读者我要写书评

暂无评论

Nano Research 2019年第4期12卷 931-938页

作者： Judun Zheng Yunxia Wu Da Xing Tao Zhang MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science South China Normal University Guangzhou 510631 China College of Biophotonics South China Normal University Guangzhou 510631 China

Cellular redox status presents broad implications with diverse physiological and pathological processes. Simultaneous detection of both the oxidative and reductive species of redox couples, especially the most representative pair glutathione/hydrogen peroxide (GSH/H2O2), is crucial to accurately map the cellular redox status. However, it still remains challenging to synchronously detect GSH/H2O2 in vivo due to lack of a reliable measuring tool. Herein, a ratiometric nanoprobe (UCNP-TB) possessing simultaneous delectability of GSH/H2O2 is established based on a multi-spectral upconverti ng nano phosphor (UCNP-OA) as the lumin esce nee res onance energy tran sfer (LRET) donor and two dye molecules as the acceptors, including a GSH-sensitive dye (TCG) and a H2O2-sensitive dye (BCH). With the as-prepared UCNP-TB, real-time and synchronous monitoring the variation of GSH and H2O2 in vitro and in living mice can be achieved using the ratio of the upcon versi on lumin esce nee (UCL) at 540 and 650 nm to that at 800 nm as the detecti on sign al, respectively, providi ng highly inhere nt reliability of the sensing results by self-calibrati on. Moreover, the nan oprobe is capable of mappi ng the redox status within the drug-resista nt tumor and the drug-induced hepatotoxic liver via ratiometric UCL imaging. Thus, this nan oprobe would provide a reliable tool to elucidate the redox state in vivo.

关键词： redox status glutathione hydrogen peroxide upconversion imaging nanoprobe

Implications of denitrification in the ecological status of an urban river using enzymatic activities in sediments as an indicator

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2019年第1期31卷 255-268页

作者： Jessica Unda-Calvo Miren Martínez-Santos Estilita Ruiz-Romera Juan Luis Lechuga-Crespo Department of Chemical and Environmental Engineering University of the Basque Country

A better understanding of the effects of a number of environmental factors on denitrification is vital for analyzing its role as nitrogen sink and providing deeper knowledge about the ecological status of a nitrate-rich ecosystem. Since few studies have addressed the occurrence and implications of denitrification in river sediments, and complexity of interactions among all these environmental factors makes comprehension of the process difficult, the potential of sediments from the Deba River to attenuate nitrate excess through denitrification was investigated. For this purpose, we adapted an in vitro method to measure activities of two enzymes contributing to the entire multiple-step nitrate reduction: Nitrate Reductase and Nitrite Reductase. The environmental features that influence both or single enzymatic activities were identified as oxygen availability,regulated directly by the moisture content or indirectly through the aerobic respiration,organic matter and nitrate content of sediments, and electrical conductivity and exchangeable sodium percentage of water. Additionally, our results showed that Nitrate Reductase catalyzes the principal limiting step of denitrification in sediments. Therefore,taking this enzymatic activity as an indicator, the southern part of the Deba River catchment presented low potential to denitrify but nitrate-limited sediments, whereas the middle and northern parts were characterized by high denitrification potential but nitraterich sediments. In general, this study on denitrifying enzymatic activities in sediments evaluates the suitability of the management of the effluents from wastewater treatment plants and municipal sewages to ensure a good ecological status of the Deba River.

关键词： Urban catchment Sediments Denitrification Enzymatic activity Ecological status

Relationship between sound signal and weld pool status in plasma arc welding

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2001年第1期11卷 54-57页

作者：王耀文陈强孙振国孙久文 Tsing Hua Univ Dept Mech Engn Beijing 100084 Peoples R China

The sound features of the weld pool status in plasma arc welding were systematically investigated after the sound signal was collected with a microphone. The results show that it is difficult to extract information about the weld pool status directly in time domain although the sound signal varies with the weld pool behaviors to some extent. The frequency spectra of the sound signal contain plenty of information about the weld pool behaviors. It is shown from the analysis of the sound generation mechanism that the sound signal of plasma arc welding is mainly caused by the weld pool oscillation, the power source fluctuation and so on. R S algorithm is designed to determine the weld pool status, and it is able to offer the feedback information for the closed loop control of the penetration quality of plasma arc welding. [

关键词： plasma arc welding weld pool status sound feature application

status and prospects of nutritional cooking

在线全文

学校读者我要写书评

暂无评论

Food Quality and Safety 2019年第3期3卷 137-143页

作者： Wang Yong Li Amin Chen Dongpo Hangzhou Robam Appliances CO. LTD.HangzhouZhejiang311100China

With the rapid development of national economic level,people’s living standards have been greatly improved,leading to people’s higher attention to their daily ***,there are still a great number of people who have not realized the importance of healthy diet,which could result in many health problems such as under-nutrition or *** cooking process has a significant impact on food nutrition,thus a fast,convenient and healthy new cooking process has a great potential to be developed and applied in our daily life.

关键词： cooking nutrition status prospects

status and distribution of ungulates in Xinjiang,China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Arid Land 2011年第1期3卷 49-60页

作者： XingYi GAO WenXuan XU WeiKang YANG David A BLANK JianFang QIAO KeFen XU Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Acad- emy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institute of Zoology Kazakhstan Academy of Sciences Almaty 050010 Kazakhstan

Based on a long-term field investigation and other research results, we reviewed the status and distribution of ungulates in Xinjiang, China. The ungulates in Xinjiang included 19 ungulate species （30 subspecies） from 6 families and 2 orders. Among them, 3 species （2 subspecies） relate to Equidae （Per- risodactyla）, and 16 species （28 subspecies） are from 5 families of Artiodactyla. In this paper, we analyzed the conservation status of most rare and important 13 ungulate species. Firstly, we proposed the protec- tion of genetic diversity of Camelus ferus and the distribution areas of Moschus sifanicus, Procapra przewalskii and Saiga tatarica in Xinjiang. We found that Moschus sifanicus but not Procapra przewalskii distributed in Xinjiang. It was not clear whether the remnant populations of Saiga tatarica existed in Xinjiang and China-Kazakhstan border or not. We discussed that the protection level and rational use of Capra si- birica and enhancing protection level and enlarging monitoring and research projects for Pantholops hodgsoni and Gazella subgutturosa. And we would like to suggest Forestry Department to develop the captive breeding of Tibetan antelope for rational use. In addition, the captive breeding of Cervus elaphus in Xinjiang was reviewed. Local government should lessen strong control to Cervus elaphus because of many breeding centers＇ establishment.

关键词： Xinjiang of China ungulate species and distribution status