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Congratulations from Prof.Han Qi-de,Vice-Chairman of the Standing Committee of the National People's Congress,Chairman of China Association for Science and Technology
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作者 韩啓德 《Chinese Journal of Integrative Medicine》 SCIE CAS 2007年第4期243-243,共1页
It is of my great pleasure to learn that the Third World Integrative Medicine Congress is about to be held in Guangzhou. rm writing to express my highest congratulations to the successful opening of the congress, as w... It is of my great pleasure to learn that the Third World Integrative Medicine Congress is about to be held in Guangzhou. rm writing to express my highest congratulations to the successful opening of the congress, as well as my cordial welcome to the experts and scholars around the world. 展开更多
关键词 Congratulations from Prof.Han Qi-de Vice-Chairman of the Standing Committee of the National People’s Congress Chairman of China Association for Science and Technology
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Challenges and Thoughts on Risk Management and Control for the Group Construction of a Super-Long Tunnel by TBM 被引量:15
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作者 Mingjiang Deng 《Engineering》 2018年第1期112-122,共11页
The total length of the second stage of the water supply project in the northern areas of the Xinjiang Uygur Autonomous Region is 540 km, of which the total length of the tunnels is 516 km. The total tun- neling milea... The total length of the second stage of the water supply project in the northern areas of the Xinjiang Uygur Autonomous Region is 540 km, of which the total length of the tunnels is 516 km. The total tun- neling mileage is 569 km, which includes 49 slow-inclined shafts and vertical shafts. Among the tunnels constructed in the project, the Ka-Shuang tunnel, which is a single tunnel with a length of 283 kin, is cur- rently the longest water-conveyance tunnel in the world. The main tunnel of the Ka-Shuang tunnel is divided into 18 tunnel-boring machine (TBM) sections, and 34 drilling-and-blasting sections, with 91 tunnel faces. The construction of the Ka-Shuang tunnel has been regarded as an unprecedented challenge for project construction management, risk control, and safe and efficient construction; it has also pre- sented higher requirements for the design, manufacture, operation, and maintenance of the TBMs and their supporting equipment. Based on the engineering characteristics and adverse geological conditions, it is necessary to analyze the major problems confronted by the construction and systematically locate disaster sources. In addition, the risk level should be reasonably ranked, responsibility should be clearly identified, and a hierarchical-control mechanism should be established. Several techniques are put for- ward in this paper to achieve the objectives mentioned above; these include advanced geological prospecting techniques, intelligent tunneling techniques combined with the sensing and fusion of infor- mation about rock parameters and mechanical parameters, monitoring and early-warning techniques, and modern information technologies. The application of these techniques offers scientific guidance for risk control and puts forward technical ideas about improving the efficiency of safe tunneling. These techniques and ideas have great significance for the development of modern tunneling technolo- gies and research into major construction equipment. 展开更多
关键词 Super-long tunnelsGroup construction by TBMRisk management and controlTechnical measures
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Formation mechanism of co-axial grain boundaries in a Mg alloy
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作者 Zhen Peng Yi Liu +7 位作者 Lirong Xiao Yue Yang Bo Gao Mengning Xu Zhaohua Hu Yandong Yu Xuefei Chen Hao Zhou 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第3期1094-1101,共8页
Due to the insufficient slip systems in hexagonal close-packed structure,twinning is frequently activated to support stable plastic deformation of Mg alloy.In this work,we found four typical twin-like interfaces with ... Due to the insufficient slip systems in hexagonal close-packed structure,twinning is frequently activated to support stable plastic deformation of Mg alloy.In this work,we found four typical twin-like interfaces with misorientations of 102°,109°,142°and 149°,respectively,which had not only a shared[1120]zone axis of neighboring grains,but also overlapped diffraction spots similar to twins.However,highresolution transmission electron microscope(HRTEM)analysis revealed that the interfaces in real space deviated from the supposed twinning planes in reciprocal space,i.e.their overlapped diffraction spots.We clarified that the incoherent interfaces were co-axial grain boundaries(CGBs).Additionally,a special angle ofθ,close to 90°,between the interface and one side of basal plane,was frequently formed in CGBs.We proposed that interaction of multiple twinning contributes to the formation of CGBs,and theθis formed due to alternative tensile and compression twinning under a uniaxial loading. 展开更多
关键词 INTERFACE TWINNING Tilt boundaries TEM Formation mechanism
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Molecular analyses display the increasing diversity of Podostemaceae in China
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作者 Zhi-Zhong Li Zhun Xu +5 位作者 Shuang Wu Lang-Xing Yuan Chun-Yu Zou Yan Liu Jian-Yong Lin Shi-Chu Liang 《Plant Diversity》 SCIE CAS CSCD 2024年第3期421-424,共4页
Podostemaceae(riverweed family),one of the largest aquatic plant families in the world,comprises about 350 species in 51 genera placed in three subfamilies,Podostemoideae,Weddellinoideae,and Tristichoideae(Koi et al.,... Podostemaceae(riverweed family),one of the largest aquatic plant families in the world,comprises about 350 species in 51 genera placed in three subfamilies,Podostemoideae,Weddellinoideae,and Tristichoideae(Koi et al.,2022).Most Podostemaceae genera(~38)are monotypic or oligotypic,with a high level of endemism(Koi et al.,2018,2022).Members of Podostemaceae adhere to rocks in fast-flowing rivers,streams,or waterfalls in the subtropics and tropics(Koi et al.,2018).As an adaptation to fastrunning currents,the morphological structure of river-weeds tends to be extremely reduced,including a loss or reduction of primary shoots or roots(Koi and Kato,2007).The vegetative mass of these plants resembles lichens or bryophytes,and are thus known commonly as“dream bryophytes”(Philbrick and Retana,1998).Podostemaceae plants flower when the water level drops during the dry season.In recent years,anthropogenic factors and climate change have severely affected river weed habitats,decreasing populations of these plants. 展开更多
关键词 ROOTS SEASON HABITAT
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Localized Electrochemical Impedance Spectroscopy Study on the Corrosion Behavior of Fe-Cr Alloy in the Solution with Cl^- and SO_4^(2-) 被引量:6
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作者 XIAO Kui ZHANG Xin +3 位作者 D0NG Chaofang WEI Dan WANG Chen LI Xiaogang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第1期27-32,共6页
The corrosion behaviors of Fe-Cr alloy under three different pH values solutions with C1- and SO42- were investigated by localized electrochemical impedance spectroscopy (LEIS) measurements and the corrosion product... The corrosion behaviors of Fe-Cr alloy under three different pH values solutions with C1- and SO42- were investigated by localized electrochemical impedance spectroscopy (LEIS) measurements and the corrosion products were analyzed by laser Raman spectrometry. The results show that the high corrosion resistance of Fe-Cr Alloy is attributed to a passive film which is formed more easily when the alloy contains a large quantity of Cr element. However, its corrosion resistance varies in the solutions with different pH values, especially in the initial corrosion. The average impedance values in neutral and alkaline solution are much higher than that in acidic solution because the passive film is more likely to dissolve in the acidic condition. Moreover, the destructive effect of C1- and SO42 ions on the passive film is also demonstrated in corrosion process through the change of the impedance value with the steeping time. 展开更多
关键词 Fe-Cr Alloy localized electrochemical impedance spectroscopy (LEIS) corrosionproducts Raman spectroscopy
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Current Situations of Edible Fungus Production in Lianyungang City and Development Countermeasures 被引量:2
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作者 LI Guan-xi GE Xiong-can WEI Liang-zhi 《Asian Agricultural Research》 2012年第9期16-19,共4页
On the basis of characteristics of edible fungus production in Lianyungang City, we analyzed its advantages and disadvantages and put forward suggestions and countermeasures for development of edible fungus industry, ... On the basis of characteristics of edible fungus production in Lianyungang City, we analyzed its advantages and disadvantages and put forward suggestions and countermeasures for development of edible fungus industry, mainly including strengthening guidance and leadership of government, introducing professional personnel, and developing the edible fungus industry through science and technology. 展开更多
关键词 EDIBLE FUNGUS CURRENT PRODUCTION SITUATIONS Existi
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Galvanic Corrosion of Magnesium Alloy and Aluminum Alloy by Kelvin Probe 被引量:5
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作者 肖葵 DONG Chaofang +2 位作者 WEI Dan WU Junsheng LI Xiaogang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第1期204-210,共7页
Galvanic corrosion on samples of AZ91D magnesium alloy coupled with 2A12 aluminum alloy during neutral salt spray test was investigated.The variations of the surface potential were measured using scanning kelvin probe... Galvanic corrosion on samples of AZ91D magnesium alloy coupled with 2A12 aluminum alloy during neutral salt spray test was investigated.The variations of the surface potential were measured using scanning kelvin probe(SKP).The results showed that galvanic effect on the corrosion of AZ91D magnesium alloy is closely related to the potential difference between the anodic and cathodic materials.In the initial period,corrosion only occurred in a narrow area at the coupling interface because of the limited distance galvanic current.Then,the corrosion rate of 2A12 aluminum alloy was accelerated due to its poor stability in strong alkali environment,which was attributed to the strong alkalization caused by the corrosion of AZ91D magnesium alloy.With the increase of the potential of 2A12 aluminum alloy as a result of the continuous covering of corrosion products,the potential difference between the two materials was enlarged,which enhanced the galvanic corrosion. 展开更多
关键词 magnesium alloy aluminum alloy galvanic corrosion scanning kelvin probe salt spray test
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Mechanical Properties of the Cured Laminates on the Hot-press Tackified Preforms in Vacuum Assisted Resin Transfer Molding 被引量:1
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作者 王长春 叶金蕊 +3 位作者 YUE Guangquan BAI Guanghui LIU Ling ZHANG Boming 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第1期242-248,共7页
A hot-press tackified preform was used to improve the uniformity of the laminates thickness and the mechanical properties of the obtained laminates were studied using vacuum assisted resin transfer molding(VARTM). T... A hot-press tackified preform was used to improve the uniformity of the laminates thickness and the mechanical properties of the obtained laminates were studied using vacuum assisted resin transfer molding(VARTM). Two modified preforms were prepared under 0.1 and 0.6 MPa in an autoclave and then were used to fabricate the laminates via VARTM. Permeability and thickness distribution of the laminates were obtained by using a special device. Moreover, the tensile and compressive strengths of the obtained laminates were studied and compared with the unmodified ones. Results show that the tackified laminates present a maximum and minimum thickness under 0.1 and 0.6 MPa, respectively. The thicknesses and in-plane permeability of the tackified laminates, with better thickness uniformity, are significantly decreased compared with that of the unmodified cases, while the tensile and compressive strengths of the tackified laminates are improved obviously. Results show that the mechanical property of the tackified laminates prepared by hotpressing at 0.1 MPa is better than that processed at 0.6 MPa. 展开更多
关键词 hot-press tackified preforms thickness uniformity mechanical property PERMEABILITY VARTM
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Overview of Ecological Agriculture with High Efficiency 被引量:1
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作者 HUANG Guo-qin ZHAO Qi-guo +1 位作者 GONG Shao-lin SHI Qing-hua 《Asian Agricultural Research》 2012年第9期71-77,共7页
From the presentation, connotation, characteristics, principles, pattern, and technologies of ecological agriculture with high efficiency, we conduct comprehensive and systematic analysis and discussion of the theoret... From the presentation, connotation, characteristics, principles, pattern, and technologies of ecological agriculture with high efficiency, we conduct comprehensive and systematic analysis and discussion of the theoretical and practical progress of ecological agriculture with high efficiency. (i) Ecological agriculture with high efficiency was first advanced in China in 1991. (ii) Ecological agriculture with high efficiency highlights "high efficiency", "ecology", and "combination". (iii) Ecological agriculture with high efficiency is characterized by diverse organisms, good environment, good structure, powerful function, good quality, high benefit, low emission, sustainability. (iv) The yield increase and efficiency increase principle of ecological agriculture with high efficiency lies in full land use, three-dimensional light use, sufficient use of season, multi-layer water consumption, efficient fertilizer consumption, symbiosis and mutual supplement, ecological disaster reduction, recycling. (v) The typical pattern of ecological agriculture with high efficiency includes three-dimensional use pattern, biological symbiosis pattern, multi-industry combination pattern, industrial extension pattern, technology-driven pattern, environmental renovation pattern, resource recycling pattern, leisure and sight-seeing pattern. (vi) The key technologies of ecological agriculture with high efficiency include resource-saving technology, water and fertilizer regulation technology, biological technology for increasing soil fertility, disaster prevention and mitigation technology, comprehensive utilization technology, water conservation technology, structural adjustment technology, energy development technology, watershed control technology, and modern high-tech technology. 展开更多
关键词 MODERN AGRICULTURE ECOLOGICAL AGRICULTURE Ecologic
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An important way to build a new socialistic countryside: developing circular economy 被引量:1
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作者 Ji Kunsen 《Ecological Economy》 2006年第2期115-126,共12页
It was put forward in the Fifth Session of Sixteenth Central Committee of the Party that "it is a great historic mission on the path for China to modernization to construct new socialistic countries", and that "acc... It was put forward in the Fifth Session of Sixteenth Central Committee of the Party that "it is a great historic mission on the path for China to modernization to construct new socialistic countries", and that "according to the requirements of developing production, ample life, civilized countryside climate, clean countryside, democratic management, urban and rural social and economic development should be unifiedly planned, modern agricultural construction should be promoted, rural reform should be deepened all round, rural public service should be advanced, and peasants' income should be increased by all means." Some time ago Premier Wen Jiabao pointed out that problems about the carrying capacity of resources and environment, for example the decrease of arable land, the lack of freshwater and eco-environmental deterioration, will be tough challenges to agricultural development in China. According to the requirement of constructing economical society and environment friendly society, agricultural circular economy should be advanced to lengthen service life of limited agricul- tural resources. In fact, this is congruous with the policy of developing agriculture by "Scientific Concept of Development". The spirit of the Fifth Session of Sixteenth Central Committee of the Party and Premier Wen Jiabao's speech will guide us to the direction of constructing new socialist countries, From the practice of developing agricultural circular economy, circular economy can be applied to expansive rural areas and is of great significance. 展开更多
关键词 中国 社会主义新农村 循环经济 资源 农产品质量
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Pinpointing the sources and measuring the lengths of the principal rivers of the world 被引量:3
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作者 S.Liu P.Lu +2 位作者 D.Liu P.Jin W.Wang 《International Journal of Digital Earth》 SCIE 2009年第1期80-87,共8页
Cultures throughout the world are associating with the rivers.People depend upon the rivers and their tributaries for food,water,transport,and many other aspects of their daily lives.Unfortunately,human beings have no... Cultures throughout the world are associating with the rivers.People depend upon the rivers and their tributaries for food,water,transport,and many other aspects of their daily lives.Unfortunately,human beings have not calculated the accurate lengths for the great rivers even today.The lengths of the rivers are very different in popular textbooks,magazines,atlases and encyclopedias,etc.To accurately determine the lengths of the principal rivers of the world,the combination of satellite image analysis and field investigations to the source regions is proposed in this paper.The lengths of the Nile,Amazon,Yangtze,Mississippi,Yellow,Ob,Yenisey,Amur,Congo and Mekong,with lengths over or close to 5000 km,were calculated using the proposed method.The results may represent the most reliable and accurate lengths of the principal rivers of the world that are currently achievable. 展开更多
关键词 principal rivers of the world sources pinpointing lengths measuring satellite remote sensing field explorations
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Highly Optimized Code Generation for Stencil Codes with Computation Reuse for GPUs
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作者 Wen-Jing Ma Kan Gao Guo-Ping Long 《Journal of Computer Science & Technology》 SCIE EI CSCD 2016年第6期1262-1274,共13页
Computation reuse is known as an effective optimization technique. However, due to the complexity of modern GPU architectures, there is yet not enough understanding regarding the intriguing implications of the interpl... Computation reuse is known as an effective optimization technique. However, due to the complexity of modern GPU architectures, there is yet not enough understanding regarding the intriguing implications of the interplay of compu- ration reuse and hardware specifics on application performance. In this paper, we propose an automatic code generator for a class of stencil codes with inherent computation reuse on CPUs. For such applications, the proper reuse of intermediate results, combined with careful register and on-chip local memory usage, has profound implications on performance. Current state of the art does not address this problem in depth, partially due to the lack of a good program representation that can expose all potential computation reuse. In this paper, we leverage the computation overlap graph (COG), a simple representation of data dependence and data reuse with "element view", to expose potential reuse opportunities. Using COG, we propose a portable code generation and tuning framework for GPUs. Compared with current state-of-the-art code generators, our experimental results show up to 56.7% performance improvement on modern GPUs such as NVIDIA C2050. 展开更多
关键词 GPGPU OPENCL STENCIL code generation computation reuse
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基础研究与国家目标——在国家重点实验室计划实施20周年、973计划实施5周年纪念大会上的报告 被引量:4
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作者 周光召 《中国基础科学》 2005年第3期3-7,共5页
关键词 国家重点实验室 计划实施 国家目标 基础研究 报告 纪念 研究员 科学家 副部长 程津培 研究所 系统
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Creating a High-Quality S&T Innovation Engine
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作者 Wan Gang 《Qiu Shi》 2018年第3期94-100,共7页
关键词 革新 质量 引擎 经济开发 经济系统 驱动力
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Trends in the Prevalence of Cognitive Impairment Among Older Adults Aged 65 to 105 Years—China,2002–2018
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作者 Xiaojin Yan Shiqi Lin +3 位作者 Jiajia Li Hao Cheng Xiangguo Liu Lijun Pei 《China CDC weekly》 2022年第42期945-949,共5页
Introduction:This study aims to analyze trends and subgroup differences in the prevalence of cognitive impairment among older Chinese adults aged 65–105 years from 2002 to 2018.Methods:Data were drawn from six waves ... Introduction:This study aims to analyze trends and subgroup differences in the prevalence of cognitive impairment among older Chinese adults aged 65–105 years from 2002 to 2018.Methods:Data were drawn from six waves of the Chinese Longitudinal Healthy Longevity Survey(CLHLS).Cognitive function was measured using the Chinese version of the Mini-Mental State Examination(CMMSE).Cognitive impairment was determined by the total CMMSE score and educational attainment of participants.The generalized estimating equation(GEE)models with a logistic link and binominal distribution were performed to assess the secular trend in the prevalence.Results:The prevalence of cognitive impairment among older adults aged 65–105 years decreased from 3.44%[95%confidence interval(CI):3.15%–3.73%]in 2002 to 2.41%(95%CI:2.17%–2.65%)in 2018 in China.The prevalence was slightly higher in women than in men in 2002(3.71%vs.3.13%,P<0.05),and there was no significant difference between women and men in 2018(2.60%vs.2.21%,P=0.12).Rural older adults had a higher prevalence of cognitive impairment before 2014,but their urban counterparts had a higher prevalence in 2018(2.75%vs.2.06%,P<0.05).The GEE regression model showed that each successive year was associated with a 3%reduction in the odds of the prevalence of cognitive impairment[odds ratio(OR)=0.97;95%CI:0.97–0.97;P<0.05].Conclusions:The prevalence of cognitive impairment among Chinese older adults aged 65–105 years declined slowly from 2002 to 2018.The gender,urban-rural,age,and regional differences in the prevalence of cognitive impairment changed over time. 展开更多
关键词 slowly NOMINAL successive
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