期刊文献+
共找到164,007篇文章
< 1 2 250 >
每页显示 20 50 100
Genetics Research and Advance on Development and Utilization of Wild Boars
1
作者 LIU Chunlong LIU Di LI Zhongqiu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期83-87,共5页
Wild boar is one of the most important beast resources. It plays an important role in the maintenance of biological diversity. The genetic resources of wild boar can not only protect the genetic resources, but also im... Wild boar is one of the most important beast resources. It plays an important role in the maintenance of biological diversity. The genetic resources of wild boar can not only protect the genetic resources, but also improve the formation of new breeds in pigs. This paper summarized the advance on the main biological characteristics of wild boars, evolutionary origin between wild boars and domesticated pigs, and development and utilization of wild boars aimed to provide further insight into wild boar's genetic research and its resource protection. 展开更多
关键词 wild boar biological characteristics GENETICS development and utilization
在线阅读 下载PDF
Comparative analysis of SIMILAR to RCD ONE(SRO)family from tetraploid cotton species and their diploid progenitors depict their significance in cotton growth and development
2
作者 SHABAN Muhammad TABASSUM Riaz +5 位作者 RANA Iqrar Ahmad ATIF Rana Muhammad AZMAT Muhammad Abubakkar IQBAL Zubair MAJEED Sajid AZHAR Muhammad Tehseen 《Journal of Cotton Research》 CAS 2024年第1期45-57,共13页
Background SRO(Similar to RCD1)genes family is largely recognized for their importance in the growth,develop-ment,and in responding to environmental stresses.However,genome-wide identification and functional character... Background SRO(Similar to RCD1)genes family is largely recognized for their importance in the growth,develop-ment,and in responding to environmental stresses.However,genome-wide identification and functional characteri-zation of SRO genes from cotton species have not been reported so far.Results A total of 36 SRO genes were identified from four cotton species.Phylogenetic analysis divided these genes into three groups with distinct structure.Syntenic and chromosomal distribution analysis indicated uneven distribu-tion of GaSRO,GrSRO,GhSRO,and GbSRO genes on A2,D5 genomes,Gh-At,Gh-Dt,Gb-At,and Gb-Dt subgenomes,respectively.Gene duplication analysis revealed the presence of six duplicated gene pairs among GhSRO genes.In promoter analysis,several elements responsive to the growth,development and hormones were found in GhSRO genes,implying gene induction during cotton growth and development.Several miRNAs responsive to plant growth and abiotic stress were predicted to target 12 GhSRO genes.Organ-specific expression profiling demonstrated the roles of GhSRO genes in one or more tissues.In addition,specific expression pattern of some GhSRO genes dur-ing ovule development depicted their involvement in these developmental processes.Conclusion The data presented in this report laid a foundation for understanding the classification and functions of SRO genes in cotton. 展开更多
关键词 COTTON SRO MIRNAS Gene duplications Gene expression Ovule development
在线阅读 下载PDF
Morphological characteristics,developmental dynamics,and gene temporal expressions across various development stages of Aphis gossypii sexual female
3
作者 LÜJingli WANG Liuyu +10 位作者 ZHANG Kaixin LI Dongyang GAO Mengxue GUO Lixiang TANG Zhijuan GAO Xueke ZHU Xiangzhen WANG Li JI Jichao LUO Junyu CUI Jinjie 《Journal of Cotton Research》 CAS 2024年第4期372-385,共14页
Background Aphis gossypii(Hemiptera:Aphididae)is a worldwide polyphagous phloem-feeding agricultural pest,and it can produce offspring by sexual or asexual reproduction.Compared with dozens of generations by parthenog... Background Aphis gossypii(Hemiptera:Aphididae)is a worldwide polyphagous phloem-feeding agricultural pest,and it can produce offspring by sexual or asexual reproduction.Compared with dozens of generations by parthenogenesis,sexual reproduction is performed in only one generation within one year,and little is known about the sexual reproduction of A.gossypii.In this study,sexual females of A.gossypii were successfully obtained through a previously established induction platform,and the morphological characteristics,developmental dynamics,and temporal gene expression were examined.Subsequently,signaling pathways potentially involved in regulating the growth,development,and reproduction of sexual females were investigated.Results The morphological observation showed that from the 1st instar nymph to adult,sexual females exhibited a gradually deepened body color,an enlarged body size,longer antennae with a blackened end,and obviously protruding cauda(in adulthood).The anatomy found that the ovaries of sexual females developed rapidly from the 2^(nd)instar nymph,and the embedded oocytes matured in adulthood.In addition,time-course transcriptome analysis revealed that gene expression profiles across the development of sexual females fell into 9 clusters with distinct patterns,in which gene expression levels in clusters 1,5,and 8 peaked at the 2^(nd)instar nymphal stage with the largest number of up-regulated genes,suggesting that the 2^(nd)instar nymph was an important ovary development period.Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis revealed that a large number of genes in the sexual female adult were enriched in the TGF-beta signaling pathway and Forkhead box O(FoxO)signaling pathway,highlighting their important role in sexual female adult development and reproduction.Conclusion The morphological changes of the sexual female at each developmental stage were revealed for the first time.In addition,time-course transcriptomic analyses suggest genes enriched in the TGF-beta signaling pathway and FoxO signaling pathway probably contribute to regulating the development and oocyte maturation of sexual females.Overall,these findings will facilitate the regulating mechanism research in the growth and development of sexual females by providing candidate genes. 展开更多
关键词 Aphis gossypii Sexual female Growth and development OOGENESIS Time-course transcriptome
在线阅读 下载PDF
An Effective 3D-CFD Methodology for the Complementary Virtual Development of Alternative Fuels and Engine Concepts
4
作者 Robin SCHMELCHER Thomas GAL +6 位作者 Mario PIPOLO Cristian TORTORELLA Antonino VACCA Edoardo ROSSI Francesco CUPO Marco CHIODI AndréCASAL KULZER 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第S01期1-8,共8页
With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the de... With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the development of new technologies.These tools are increasingly used by manufacturers,as a screening process before building the first prototype.This paper presents an innovative methodology for virtual engine development.The 3D-CFD tool QuickSim,developed at FKFS,allows both a significant reduction in computation time and an extension of the simulated domain for complete engine systems.This is possible thanks to a combination of coarse meshes and self-developed internal combustion engine models,which simultaneously ensure high predictability.The present work demonstrates the capabilities of this innovative methodology for the design and optimization of different engines and fuels with the goal of achieving the highest possible combustion efficiencies and pollutant reductions.The analysis focuses on the influence of different fuels such as hydrogen,methanol,synthetic gasolines and methane on different engine geometries,in combination with suitable injection and ignition systems,including passive and active pre-chambers.Lean operations as well as knock reduction are discussed,particularly for methane and hydrogen injection.Finally,it is shown how depending on the chosen fuel,an appropriate ad-hoc engine layout can be designed to increase the indicated efficiency of the respective engines. 展开更多
关键词 eFuels METHANE METHANOL hydrogen CO_(2)reduction virtual development 3D-CFD
在线阅读 下载PDF
Future China-Africa research collaboration in geoscience:Challenges and opportunities
5
作者 Michael H.STEPHENSON Hassina MOURI +5 位作者 Gbenga OKUNLOLA CHENG Li WANG Meng ZHAO Yu GU Liping WANG Chengshan 《地学前缘》 北大核心 2025年第1期459-465,共7页
At the 19th G20 Summit in Brazil in November 2024,China promoted the development of sustainable solutions to climate change,biodiversity loss,and environmental pollution.This continued the theme of the 2016 G20 Hangzh... At the 19th G20 Summit in Brazil in November 2024,China promoted the development of sustainable solutions to climate change,biodiversity loss,and environmental pollution.This continued the theme of the 2016 G20 Hangzhou Summit,at which China placed development at the center of the G20’s macroeconomic policy coordination for the first time,adopting the G20 Action Plan on the United Nations 2030 Agenda for Sustainable Development and the G20 Initiative on Supporting Industrialization in Africa and Least Developed Countries.In Brazil,China announced actions on advancing modernization in Africa over the next three years with a Chinese commitment of RMB360 billion yuan in financial support.In this article,we examine the potential role of geoscience research and practice in development,particularly in the sustainable use of natural resources,the prevention of climate change impacts,as well as mitigation of geo-hazards and their health implications,indicating the areas where China’s geoscience for Africa is strong and where it requires more effort.We find that although China is the world’s leading publisher of scientific papers,its contribution to geoscience in Africa(the globe’s fastest-growing economic area),as shown by bibliometric research,appears to be rather small and inconsistent with the research priorities of Africa.Amongst the priorities for geoscience research in Africa,which are not addressed substantially by the research conducted so far,are sustainable mineral and hydrocarbon development,hydrology and hydrogeology,climate change and resilience,natural hazards,medical geology,agrominerals,and geoscience education and training.A particular opportunity for African nations is the presence of critical minerals-minerals needed for the energy transition and for batteries for electric cars in particular.Africa is well-endowed with many of these critical materials,such as rare earth elements and platinum group metals.Several research groups stress the need for the agency on the part of African institutions to map out these valuable resources,understand their value and the economics and sustainability of their extraction,encourage local business,attract investment,and scrutinize proposals from potential international investors to get the best deals.A strong point of existing China-led geoscience development includes the Deep-time Digital Earth(DDE)program online computing platform and its artificial intelligence tool GeoGPT,which is being developed in partnership with Zhejiang Laboratory.These are being developed with strong China funding support for free and wide global access,with a particular focus on Africa.These advanced tools will help to place the agency of development squarely in the hands of African scientists and institutions.In summary,the following are recommended:(1)a more coordinated and strategic approach to China-led geoscience research in Africa;(2)an Africa-centered,geoscience funding initiative that concentrates on relevant topics to the continent such as critical minerals exploration and other geological resources,materials and processes and their health implications on the populations and ecosystems in general,as well as climate change and climate change resilience;and(3)continued support for China-led international initiatives that seek to increase the agency and capacity of Africa geoscience researchers,for example the Deep-time Digital Earth platform. 展开更多
关键词 open science sustainable development digital empowerment China-Africa geo-collaboration Deep-Time Digital Earth
在线阅读 下载PDF
N^(6)-methyladenosine modification and skin diseases
6
作者 JIANG Ling HU Yibo CHEN Jing 《中南大学学报(医学版)》 北大核心 2025年第3期382-395,共14页
Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of... Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of Science for literature related to m^(6)A and dermatological conditions.Analysis of citation counts and journal impact factors revealed a significant upward trend in the volume of m^(6)A-related research.Term frequency analysis of titles and abstracts indicated that studies mainly focus on skin tumors and inflammatory or immune-related skin diseases,particularly melanoma,psoriasis,and skin development.Transcriptomic data from the Gene Expression Omnibus(GEO)were analyzed,revealing differential expression of m^(6)A-related genes in 4 types of skin tumors(including squamous cell carcinoma and basal cell carcinoma)as well as in inflammatory skin diseases such as psoriasis and atopic dermatitis,and potential mechanisms of action were also explored.Findings suggest that m^(6)A modifications exhibit heterogeneity between neoplastic and nonneoplastic skin diseases.However,the regulatory mechanisms of m^(6)A dynamic modifications on key genes involved in dermatological disorders remain unclear and warrant further investigation. 展开更多
关键词 skin tumors inflammatory and immune-related skin diseases N^(6)-methyladenosine EPIGENETICS drug development
在线阅读 下载PDF
DEVELOPMENT AND ERROR ANALYSIS OF AN INSPECTING SYSTEM FOR MEASURING THE ROTATIONAL INERTIA OF BULLETS 被引量:15
7
作者 车英 李占国 +3 位作者 陈礼华 白素平 马宏 韩文波 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算... 介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算公式,分析了产生测量误差的因素,进行了定量精度分析,给出了实验结果与测量精度。 展开更多
关键词 转动惯量 摆动周期 测量误差 development and ERROR ANALYSIS OF AN INSPECTING
在线阅读 下载PDF
安氏新银鱼(Neosalanx anderssoni)性别特异性位点筛选及性别鉴定方法开发
8
作者 王心悦 邢腾飞 +2 位作者 杨昊 李玉龙 刘进贤 《海洋与湖沼》 北大核心 2025年第2期467-474,共8页
安氏新银鱼是我国重要的小型经济鱼类物种,具有较高的经济价值。但目前缺乏一种快速、经济有效的性别鉴定方法,极大地阻碍了其性别决定分子机制、性染色体演化历程的研究和水产育种与养殖技术方面的生产实践。本研究通过比较安氏新银鱼... 安氏新银鱼是我国重要的小型经济鱼类物种,具有较高的经济价值。但目前缺乏一种快速、经济有效的性别鉴定方法,极大地阻碍了其性别决定分子机制、性染色体演化历程的研究和水产育种与养殖技术方面的生产实践。本研究通过比较安氏新银鱼雌性与雄性的全基因组重测序数据,发现雌雄之间存在一个显著差异的基因组区域(chr02:2798574~5434239 bp)。基于测序深度差异分析筛选得到3个雌性特异性片段,长度分别为10 bp、167 bp和53 bp。在长为167 bp的雌性特异性位点附近设计引物,PCR扩增及凝胶电泳结果显示,雌性在该区域扩增产物具有2条带,雄性具有1条带,且雄性条带的亮度高于雌性两条带的亮度。该引物可以有效地区分安氏新银鱼的遗传性别,并分别在双洋港、秦皇岛已知性别的两个群体22个雌性和22个雄性个体中得到了验证。为了进一步验证研究结果的可靠性,分别从两个群体中随机选取雌雄个体样本的PCR产物进行测序分析,结果与预期相符,体现了该方法的有效性。研究结果也支持安氏新银鱼的性别决定系统为ZZ/ZW系统。本研究开发的方法可快速有效鉴定安氏新银鱼的遗传性别,并为该物种性别决定遗传机制及性染色体演化等后续研究提供理论支撑。 展开更多
关键词 安氏新银鱼 雌性特异性位点 遗传性别鉴定 性别决定系统 引物开发
在线阅读 下载PDF
Exploitation of Wild Flowers and the Sustainable Development of Flowers Industry in China 被引量:4
9
作者 HONG Li PANG Songling ZHUO Lihuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期76-79,共4页
This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic res... This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic resources and the sustainable development of flowers and plants industry in China, and put forward some proposals on the existing question and the prospects for the development. 展开更多
关键词 wild flowers and plants development and utilization flowers and plants industry sustainable development
在线阅读 下载PDF
Issues and Development Opportunities of Aquatic Product Industry in China 被引量:5
10
作者 GAO Shenrong TONG Xia WU Linhai 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第2期87-91,共5页
China is the largest producer and trader of aquatic products in the world, but does not mean that it belongs to the strongest power group of aquatic production and trade. This paper objectively analyzed the main probl... China is the largest producer and trader of aquatic products in the world, but does not mean that it belongs to the strongest power group of aquatic production and trade. This paper objectively analyzed the main problems existing in the highspeed development of China's aquatic product industry by empirical analysis. For example, the situation of quality and safety of aquatic products is serious now; the basic conditions of aquaculture lag behind the production development; aquatic industry is still in a low level of development and organization; and the quality and safety of aquatic products is the most main problem. This paper also revealed that fish would be the main source of animal-derived food, and the demand of characteristic aquatic products would continuously go up. Aquatic processing has initially formed a standard system. It drew a conclusion that it would be a good opportunity for China's aquatic processing industry in the future 展开更多
关键词 aquatic product development status future opportunity
在线阅读 下载PDF
Performance and Nutrient Utilization of Layers Fed Diet Supplemented with Microbial Phytase and Cellulase 被引量:2
11
作者 WANG Li juan,SHAN An shan,SONG Jin cai (Animal Nutrition Institute,Northeast Agricultural University,Harbin Heilongjiang,150030,PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第1期33-39,共7页
A 31 week feeding trial was conducted to investigated the effects of dietary supplementation of microbial phytase and cellulase on performance,nutrients utilization and tibia quality of laying hens fed maize and soyb... A 31 week feeding trial was conducted to investigated the effects of dietary supplementation of microbial phytase and cellulase on performance,nutrients utilization and tibia quality of laying hens fed maize and soybean meal diets.192 18 week old Hisex layers were used in the trial A 2×2×2 factorial design was used in the experiment with three factors of two levels each:0 38% and 0 16% of dietary non phytate P(nP).0 and 300 U·kg -1 of phytase (Ph),and 0 and 0 10% of cellulase (Ce).The results showed that supplementation of 300 U·kg -1 phytase significantly improved utilization of dietary crude ash,CP,Ca,total P and copper (P<0 05),and improved tibia breaking strength (P<0 05).No effect of phytase on performance was observed.Addition of 0 10% cellulase decreased feed intake (P<0 05),increased utilization of CF (P<0 05) and Ca(P<0 01),and decreased total tibia ash weight (P<0 05).300 U·kg -1 phytase and 0 10% cellulase exhibited obvious positive interactions to enhance utilization of dietary phytic P and copper (P<0 05).0 16% nP did not reduce performance of the layers,but improved egg shell quality at 20 wks,increased utilization of dietary total P,phytic P and Copper (P<0 01),decreased utilization of dietary CP,increased tibia breaking strength and Ca,Mn contents of tibia(P<0 01) 展开更多
关键词 microbial phytase CELLULASE LAYERS PERFORMANCE utilization of nutrientss
在线阅读 下载PDF
Dynamic bandwidth allocation algorithm for full-band utilization 被引量:1
12
作者 Han Guodong Wang Hui Wu Jiangxing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期223-229,共7页
To improve and optimize the bandwidth utilization for multi-service packet transporting system, a kind of Dynamic Full Bandwidth Utilized (DFBU) allocation algorithm allowing a single link to use far beyond its fair... To improve and optimize the bandwidth utilization for multi-service packet transporting system, a kind of Dynamic Full Bandwidth Utilized (DFBU) allocation algorithm allowing a single link to use far beyond its fair share bandwidth is presented. Three important parameters as the bound on max and minimum bandwidth, the maximum packet delay and the minimum bandwidth utilization are discussed and analyzed. Results of experiments show that the DFBU-algorithm is capable of making a single link in the system use all the spare bandwidth (up to full-bandwidth) while the performance of fairness and QoS requirement is still guaranteed. 展开更多
关键词 full-band utilize dynamic allocation algorithm FAIRNESS bandwidth utilization
在线阅读 下载PDF
Regulation of Foliar Application DCPTA on Growth and Development of Maize Seedling Leaves in Heilongjiang Province 被引量:4
13
作者 Gu Wan-rong Meng Yao +4 位作者 Zhang Jun-bao Ji Biao Wang Yong-chao Li Jing Wei Shi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第2期1-11,共11页
DCPTA (2-diethylaminoethyl-3, 4-dichlorophenylether) is a new plant regulator which can be used to regulate growth and development for crops. Experiments on maize seedlings were conducted in the growth chamber to st... DCPTA (2-diethylaminoethyl-3, 4-dichlorophenylether) is a new plant regulator which can be used to regulate growth and development for crops. Experiments on maize seedlings were conducted in the growth chamber to study the effects of foliar applied DCPTA. The plant pots were placed in a completely randomized design with three replicates. The maize seedlings were treated with 0 mg·L-1 (control), 20 mg·L-1 and 40 mg·L-1 DCPTA solution. The effects of DCPTA on the photosynthetic characteristics (photosynthesis, stomata conductance, intercellular CO2, and transpiration rate), related physiological characteristics (contents of soluble sugar and starch), chlorophyll fluorescence parameters (Fo, Fro, Fv/Fm, Fv/Fo, qP, and qN) and the weight of dry matter in maize seedling were studied. The results showed that DCPTA enhanced photosynthesis of maize seedling. In general, photosynthetic rate in leaves was significantly promoted through spraying DCPTA solution, and 40 rag" L~ DCPTA was found to be the best concentration for maize. The relationship between stomata conductance and transpiration rate in maize leaves could be described as linear. With regard to the chlorophyll fluorescence parameters, our fmdings showed that 40 mg·L-1 DCPTA in maize seedling caused an increase in Fm, Fv/Fm, Fm/Fo, qP and a decrease in Fo and qN at some time points checked. It is suggested that DCPTA increased photosynthetic rate by raising both the content of chlorophyll and activities of PSII and the contents of sugar and starch. Compared with the control, the treated maize seedling caused an increase in plant height, root length, shoot dry mass, root dry mass, or the total (root plus shoot) dry mass. 展开更多
关键词 DCPTA PHOTOSYNTHESIS growth and development maize seedling
在线阅读 下载PDF
A review on lightweight materials for defence applications:Present and future developments 被引量:10
14
作者 Suchart Siengchin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期1-17,共17页
The defence sector is now at an advanced level,catering to the global scenario,and countries also invest heavily in research and development.Countries around the world have spent a lot of money on research and develop... The defence sector is now at an advanced level,catering to the global scenario,and countries also invest heavily in research and development.Countries around the world have spent a lot of money on research and development over the years in order to stay ahead of their competitors.Lightweight materials are critical in defence applications because they allow components to be lighter without sacrificing strength.This review provides an overview of the research related to defence applications.The book provides comprehensive details on current trends in the application of lightweight materials in defence.This review also includes historical and current perspectives on defence technologies.It discusses uses of lightweight materials such as metal matrix composites,polymer composites,ceramic matrix composites,fiber composites in defence sectors Finally,the review paper also emphasizes future military applications of lightweight materials. 展开更多
关键词 Lightweight materials DEFENCE TECHNOLOGIES developmentS APPLICATIONS
在线阅读 下载PDF
Development and Application of a Shaft-type Tubular Pumping System with a Siphon Discharge Passage 被引量:7
15
作者 ZHANG Ren-tian ZHU Hong-geng DAI Long-yang 《南水北调与水利科技》 CAS CSCD 北大核心 2013年第1期J0001-J0006,共6页
Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft su... Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft suction box and a siphon-type discharge passage with a vacuum breaker as the cutoff device was developed , which possesses such advantages as simple structure , reliable cutoff , and high energy performance.Taking some pumping stations as the case studies , in the light of the specified operation conditions , the hydraulic optimal design of the shaft-type tubular pumping system was determined and the optimized shape of the system was recommended.The performance prediction based on the computational fluid dynamics methodology was determined and the model test verification was conducted.The results show that the predicted data agree with the experimental head and efficiency so that both methods can be used to determine the performance of a real pumping station.Finally , the in-situ measurements of a pumping station during the commissioning period further verified that the shaft-type tubular pumping station with a siphon discharge passage is of higher efficiency , more reliable and stable. 展开更多
关键词 shaft-type tubular pumping station siphon discharge passage development application hydraulic optimal design model test
在线阅读 下载PDF
Science Research and Utilization Planning of China’s Space Station in Operation Period 2022–2032 被引量:6
16
作者 GU Yidong GAO Ming ZHAO Guangheng 《空间科学学报》 CAS CSCD 北大核心 2020年第5期609-614,共6页
The core module of China’s Space Station(CSS)is scheduled to be launched around the end of 2020,and the experimental module I and II will be launched in the next two years.After on-orbit constructions,CSS will be tra... The core module of China’s Space Station(CSS)is scheduled to be launched around the end of 2020,and the experimental module I and II will be launched in the next two years.After on-orbit constructions,CSS will be transferred into an operation period over 10 years(2022–2032 and beyond)to continuously implement space science missions.At present,based on the project selection and research work in the ground development period of CSS,China is systematically making a utilization mission planning for the operation period,which focuses on the fields of aerospace medicine and human research,space life science and biotechnology,microgravity fluid physics,combustion science,materials science,fundamental physics,space astronomy and astrophysics,Earth science,space physics and space environment,space application technology,etc.In combination with the latest development trend of space science and technology,China will continue to update planning for science research and technology development,carry out project cultivation,payload R&D,and upgrade onboard and ground experiment supporting systems to achieve greater comprehensive benefits in science,technology,economy,and society。 展开更多
关键词 China’s space station utilization PLANNING EXPERIMENT
在线阅读 下载PDF
Research Status and Development Direction of Gas-containing Coal Seepage Model 被引量:17
17
作者 程波 《矿业安全与环保》 北大核心 2017年第5期93-97,共5页
在线阅读 下载PDF
Design and Development of TGPSIS Based on SuperMap—Map Subsystem 被引量:1
18
作者 LI Changzhi~1 LIU Xingnian~2 CAO Shuyou~2 WANG Zhaoyin~(1,3) (1.China Inst.of Water Resources and Hydropower Research,Beijing 100038,China 2.State Key Lab.of Hydraulics and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China 3.Dept.of Hydraulic Eng.,Tsinghua Univ.,Beijing 100084,China) 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2005年第S1期133-137,共5页
The Three Gorges Project (TGP for short) is the key project to train and develop the Yangtze River of China,with multi-objects of flood defence,electricity generation,shipping,etc.However,sediment plays an important r... The Three Gorges Project (TGP for short) is the key project to train and develop the Yangtze River of China,with multi-objects of flood defence,electricity generation,shipping,etc.However,sediment plays an important role in beth constructing of engineering and exerting efficiency of TGP.Special attention,there- fore,has been paid to sediment problem of TGP since the very beginning of this engineering's pregnancy.Up to now,much observed data and fruitful researches about TGP have come into being,and a sci... 展开更多
关键词 TGPSIS SEDIMENT design and development
在线阅读 下载PDF
Application and Development of Biosensors 被引量:1
19
作者 GAO Yuelin LI Jichang HUO Guicheng LIU Libo 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期80-83,共4页
As a new kind of analytical instrument, the principles, types and characters of biosensors were discussed in this paper. A biosensor is usually composed of a recognition element of biological origin and a physicochemi... As a new kind of analytical instrument, the principles, types and characters of biosensors were discussed in this paper. A biosensor is usually composed of a recognition element of biological origin and a physicochemical transducer. The biological element is capable of sensing the presence, activity or concentration of a chemical analyse in solution. The sensing takes place either as a binding event or a biocatalytical event. These interactions produce a measurable change in a solution property, in which the transducer is converted into a quantifiable electrical signal. The principles, types and applications of biosensors in environmental inspection, food production, clinical medicine and military defense were reviewed, and the trends in research were predicated, Furthermore, an attempt had been made to describe the future development directions and prospects. 展开更多
关键词 biosensors development APPLICATION
在线阅读 下载PDF
Exploring harmonious development between urbanization and eco-environment based on climate analysis—A study in Changsha, China 被引量:4
20
作者 刘少博 魏春雨 +4 位作者 郭亚琦 曾晓霞 柳肃 尹怡诚 刘云国 《Journal of Central South University》 SCIE EI CAS 2011年第1期101-107,共7页
The process of urbanization affects the urban warming.The change of urban warming was investigated by several urbanization factors in Changsha,China.The data of surface temperature(minimum,maximum and mean) of Changsh... The process of urbanization affects the urban warming.The change of urban warming was investigated by several urbanization factors in Changsha,China.The data of surface temperature(minimum,maximum and mean) of Changsha were analyzed to understand the possible effects of urbanization on the climate of this region owing to the population growth,built-up area expansion and energy consumption increases.The weights of these three factors were calculated by the analytical hierarchy process(AHP).Then,three weights were simulated with nonlinear method to obtain the urbanization development rate which was utilized to reveal the influence of the urbanization factors on the surface temperature.The result shows that there is a significant upward trend in the urban temperatures of Changsha.The temperature increase seems to be closely related to the rate of urbanization between 1993 and 2008,and there is an evidential increase trend of the influence on urban temperature by urbanization during 16 years.It is a quantifiable approach measuring the relationship between urbanization and urban eco-environment,and can be applied for the urban sustainability. 展开更多
关键词 URBANIZATION urban warming eco-environment effects harmonious development Changsha
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部