期刊文献+
共找到74,444篇文章
< 1 2 250 >
每页显示 20 50 100
Study on Regionalization of High Efficiency Eco-agriculture in Eco-economic Zone of Poyang Lake 被引量:11
1
作者 戴天放 章志发 《Agricultural Science & Technology》 CAS 2010年第8期57-60,共4页
The high efficient eco-agricultural zone in Eco-economic Region of Poyang Lake was divided into three different areas. 12 indicators including per capita cultivated land,forest coverage,comprehensive utilization rate ... The high efficient eco-agricultural zone in Eco-economic Region of Poyang Lake was divided into three different areas. 12 indicators including per capita cultivated land,forest coverage,comprehensive utilization rate of straw,the ratio of the effective irrigation area to the arable land,amount of pesticide usage per unit area of arable land,the output value ratio of planting industry,the output value ratio of forestry and fruit industry,the output value ratio of stock farming,the output value ratio of fishery,the proportion of sown area of crop,proportion of sown area of oil plants and the proportion of sown area of vegetable were screened to construct the indicator system of regionalization of high efficient eco-agriculture. The average index values of the high efficient eco-agricultural regionalization of three regions were obtained,the development direction of the efficient eco-agriculture construction of three areas were analyzed according to the natural resources characteristics f eco-agricultural and requirements of high efficient eco-agricultural development of the regions. 展开更多
关键词 Poyang Lake eco-economic Region Efficient eco-agriculture REGIONALIZATION
下载PDF
Study on Planning and Design Mode of Eco-agricultural Demonstration Base in Poyang Lake Eco-economic Zone 被引量:2
2
作者 魏朝俊 徐芳 《Journal of Landscape Research》 2012年第6期24-26,共3页
Guided by the Planning of Poyang Lake Eco-economic Zone, traffic and geographic conditions of the Eco-agricultural Demonstration Base in the study area were analyzed, and design principles proposed as "adaptation... Guided by the Planning of Poyang Lake Eco-economic Zone, traffic and geographic conditions of the Eco-agricultural Demonstration Base in the study area were analyzed, and design principles proposed as "adaptation to local conditions, scientific planning, benign circulation and sustainable development". Detailed planning and design was interpreted from the perspectives of infrastructure planning and functional area planning. Specifically, infrastructure construction should focus on traffic design, water, power and gas supply design, and also architectural design; while functional areas should be gradually developed from south section to central and then north section. It was to establish a design and planning mode that can be widely applied. 展开更多
关键词 PLANNING of Poyang Lake eco-economic zone PLANNING and design of eco-agricultural BASE PLANNING of functional area Widely-applicable MODE
下载PDF
Legal System for China's Forest Resource Protection:A Case Study of Poyang Lake Eco-economic Zone 被引量:2
3
作者 LIU Rui-zhan 1 ,SONG Ping1,SHENG Qiu-ying2,GONG Wen-jun2 1.Jingdezhen City Forestry Bureau,Jingdezhen 333000,China 2.Jingdezhen City Forest Research Institute,Jingdezhen 333000,China 《Asian Agricultural Research》 2012年第7期65-68,共4页
Taking Poyang Lake Eco-economic Zone as an example,we analyzed existing problems in China'forest resource protection from the perspective of legal system.The problems include unclear property right system of fores... Taking Poyang Lake Eco-economic Zone as an example,we analyzed existing problems in China'forest resource protection from the perspective of legal system.The problems include unclear property right system of forest resource,imperfect compensation mechanism for forest ecology,forest cutting quota scheme not resolutely put into practice,legal supervision of forest protection not implemented,and lack of integration in forest protection laws.Based on these problems,we put forward countermeasures and suggestions:establish clear forest resource property system;improve ecological benefit compensation mechanism in legal form;strictly implement forest cutting quota scheme;strengthen legal supervision of forest protection;and keep legal system integral for forest resource protection. 展开更多
关键词 FOREST resource Protection LEGAL AWARENESS Poyang
下载PDF
Construction and Strategic Vision of the Capital Eco-economic Zones
4
作者 张义丰 兰婷婷 +1 位作者 刘春腊 张宏业 《Journal of Resources and Ecology》 CSCD 2010年第3期283+274-282,共10页
北京作为全国的政治、经济、文化中心,具有强大的综合创新优势,必须在实现经济体系高效性与生态系统稳定性上做出表率,建设首都生态经济区是北京山区科学发展的必然趋势。首都生态经济区地域范围为北京的七山区县,其建设要以"两山... 北京作为全国的政治、经济、文化中心,具有强大的综合创新优势,必须在实现经济体系高效性与生态系统稳定性上做出表率,建设首都生态经济区是北京山区科学发展的必然趋势。首都生态经济区地域范围为北京的七山区县,其建设要以"两山、五河、七组团"为空间结构,以"一区、三基地、一平台"为框架性目标。作为探索北京山区环境、经济与社会协调发展的路径,建设首都生态经济区是优化山区生态环境建设的现实需要,符合山区发展转型的客观要求,具有重要的科学意义、实践基础和理论依据,应遵循打破行政界限、生态主导发展等原则,力争用10-15年的时间,建设生态产业经济带(走廊)、拓展生态经济区地域空间范围、打造中国北部生态经济增长极,以建设成北京绿色崛起先导区和全国生态经济示范区。 展开更多
关键词 Capital eco-economic zones Beijing mountainous areas development strategy
原文传递
Spatio-temporal difference analysis of cultivated land use intensity based on emergy in the Poyang Lake Eco-economic Zone of China 被引量:7
5
作者 XIE Hualin HE Yafen +1 位作者 ZOU Jinlang WU Qun 《Journal of Geographical Sciences》 SCIE CSCD 2016年第10期1412-1430,共19页
Taking the emergy requirements of the five input indexes as the foundation, this paper analyzes the total temporal and spatial changes in cultivated land use intensity in the Poyang Lake Eco-economic Zone from 2000 to... Taking the emergy requirements of the five input indexes as the foundation, this paper analyzes the total temporal and spatial changes in cultivated land use intensity in the Poyang Lake Eco-economic Zone from 2000 to 2010. The results are obtained as follows: (1) Over a period of 10 years, the cultivated land use intensity has increased exponentially in the Poyang Lake Eco-economic Zone; agricultural machinery intensity has been the largest proportion of the total inputs, comprising more than 99.50% and increasing year by year, which indicates that agricultural mechanization is a basic trend in agricultural development in the Poyang Lake Eco-economic Zone. (2) The total number of counties belonging to the moderate- and low- intensity cultivated land use categories is the largest, while the number of counties belonging to the high-intensity cultivated land use and extensive cultivated land use categories is the smallest. (3) This zone can be divided into five areas: an eastern area of high-intensity cultivated land use, a central and eastern area of low-intensity cultivated land use, a central area of low-intensity cultivated land use, a southern area of moderate-intensity cultivated land use, and a northern area of moderate-intensity cultivated land use. (4) The counties which had a coordinated development between cultivated land use intensity and their socio-economic development level increase year by year, and the socio-economic development level had increasingly obvious effects on the cultivated land use intensity. Finally, this paper presents suggestions for the development of cultivated land use intensity in the Poyang Lake Eco-economic Zone, especially for different levels of intensity among counties. 展开更多
关键词 cultivated land land use intensive emergy term Poyang Lake eco-economic zone
原文传递
Sustainable Livelihood Security in the Poyang Lake Eco-economic Zone:Ecologically Secure,Economically Efficient or Socially Equitable?
6
作者 WU Zhilong ZENG Tian HUANG Jin 《Journal of Resources and Ecology》 CSCD 2022年第3期442-457,共16页
Sustainable Livelihood Security(SLS)remains a rarely considered yet important issue for rural sustainability and natural resource management.Particularly in China,rural SLS research in a typical area is urgently neede... Sustainable Livelihood Security(SLS)remains a rarely considered yet important issue for rural sustainability and natural resource management.Particularly in China,rural SLS research in a typical area is urgently needed,but insufficient under the background of National Rural Revitalization and Ten-year Fishing Ban of Yangtze River.Focusing on the policy-targeted inland lake area,we proposed a Livelihood Security Analysis(LSA)framework by establishing an adaptive indicator system and integrating multiple econometrical and geographical methods.This study aims to evaluate the SLS in Poyang Lake Eco-economic Zone comprehensively from the three aspects of ecology,economy and society,analyze their spatial patterns,identify the main constraints,and finally give specific suggestions for improving rural sustainability management.The results showed that rural SLS in the inland great lake area tended to be vulnerable mainly due to the lagging economic efficiency and unbalanced social equality,and mediated by regional ecological characteristics.The overall SLS and Ecological Security Index(ESI)were higher in the north and lower in the south,while Economic Efficiency Index(EEI)and Social Equality Index(SEI)were at the middle level and circularly distributed around Nanchang City.The dominating factors which have greatly shaped the spatial pattern of SLS include rural per capita electricity consumption,fishery breeding area,population dependency ratio,urbanization rate,and fishery population.The obstacle degree is ranked as economic system>social system>ecological system.An outdated economy and incomplete social services are the main constraints,characterized by weak electricity consumption,limited beds in hospitals,low urbanization rate,deficient agricultural machinery power,and a small agricultural output value.Therefore,one urgent need is to activate the rural economy by reinforcing rural electric power facilities and promoting agricultural mechanization.In addition,transforming the peasants/fishermen to the non-agricultural sector should be accelerated,which will help to reduce ecological pressure,boost urban-rural integration and narrow the income gap. 展开更多
关键词 sustainable livelihood security methodological framework spatial pattern influencing factors Poyang Lake eco-economic zone
原文传递
Industrial Greening of the Dongting Lake Eco-economic Zone
7
作者 Da-yuan Li Min Huang 《Frontiers of Engineering Management》 2015年第3期228-233,322,共7页
Extensive industrial development is a major challenge to ecological civilization construction. Industrial energy consumption and environmental pollution reduction are desperately needed. The Dongting Lake district, lo... Extensive industrial development is a major challenge to ecological civilization construction. Industrial energy consumption and environmental pollution reduction are desperately needed. The Dongting Lake district, located in Wuhan and the Changsha-Zhuzhou-Xiangtan(CZT)pilot zone, bears the responsibility to ensure national food security and watershed ecological security, and it is an urgent need for the Dongting Lake district to accept the ecological transition of industries. On the analysis of the industrial development status and problems of the Dongting Lake district, some proposals based on the characteristics and reality of the district are pointed out, such as industrial cooperation, proper space layout, ecological innovation, industrial structure upgrading, building of ecological parks, clean production, elimination of backward production capacity, heavy metals governance and so on, as to develop the industrial ecology of the Dongting Lake district. 展开更多
关键词 industrial greening changing patterns of development ecological civilization regional collaboration the Dongting Lake eco-economic zone
原文传递
Tourism Development Strategy in Poyang Lake Eco-economic Area from the Perspective of Industrial Cluster
8
作者 严宽荣 《Journal of Landscape Research》 2010年第3期67-70,共4页
As a regional tourism development strategy, tourism industrial cluster can promote the core competitiveness of tourism industry in advantageous regions and the great-leap-forward development of regions with less-devel... As a regional tourism development strategy, tourism industrial cluster can promote the core competitiveness of tourism industry in advantageous regions and the great-leap-forward development of regions with less-developed tourism industry. The conditions of forming tourism industrial cluster in Poyang Lake Eco-economic Area was analyzed, the development strategies for tourism industry from the perspective of industrial cluster was put forward. 展开更多
关键词 Industrial cluster Poyang Lake eco-economic Area Tourism industry
下载PDF
Complementary Zoning Frameworks for Sustainable Management of Eco-economic Capital:a Case Study of Lijiang,China 被引量:1
9
作者 YANG Dewei QIU Quanyi LIU Wenjuan 《Journal of Mountain Science》 SCIE CSCD 2012年第6期760-769,共10页
We propose two zoning frameworks for regional decision-makers to regulate eco-economic capital in Lijiang,southwest China,using an index system,layer overlay,and GIS spatial analysis.The frameworks include eco-economi... We propose two zoning frameworks for regional decision-makers to regulate eco-economic capital in Lijiang,southwest China,using an index system,layer overlay,and GIS spatial analysis.The frameworks include eco-economic zoning and major function-oriented zoning,with an emphasis on ecoeconomic capital and human activities.The two frameworks share common advantages in top-down resource regulation by a certain function and the pursuit of competitiveness,sustainability and welfare fairness.Their differences in development orientation,functional links and scale suitability provide a complementary approach for regional decisionmakers.The frameworks will help to understand complex eco-economic resource patterns and foster appropriate regional regulation strategies. 展开更多
关键词 CAPITAL eco-economic zoning GIS Function-oriented zoning
下载PDF
Eco-economic evolution, emergy evaluation and policy options for the sustainable development of Tibet 被引量:13
10
作者 YAN Mao-chao, H. T. Odum ( Commission for Integrated Survey of Natural Resources, Chinese Academy of Sciences, Beijing, China, Center for Environmental Policy, Department of Environmental Engineering Sciences, University of Florida, Gainesville, FL, USA) 《Journal of Geographical Sciences》 SCIE CSCD 2000年第1期1-27,共27页
As economies and ecological support systems become more interdependent, new disciplines are needed to 'bridge the gap' of understanding between societies and nature. It is now clear that neither ecology nor ec... As economies and ecological support systems become more interdependent, new disciplines are needed to 'bridge the gap' of understanding between societies and nature. It is now clear that neither ecology nor economics alone can address the problems of our global commons. New measures of wealth, of value, of contributions and production are needed that acknowledge the 'natural capital' and 'ecosystem services' provided from healthy environments. A new interface is now being recognized termed 'eco-economics'. It is an ambitious and necessary attempt to understand the affairs of humanity and nature as a single, interdependent system. New tools are being invested to measure wealth. services and production fairly and equitably. In this report we use systems analysis approach to study the combined ecological-economic system of Tibet We use an alternative measure of value, based on real contributions to system performance, termed EMERGY, spelt with an 'M'. It is an accounting unit of total contributions, direct and indirect. used in generating a product or service. It is a concept derived from understanding whole systems, their interactions and interdependence, and the resources driving and maintaining them. This broader approach will help us to investigate Tibetan resources utilization and potentialities and exchange. Emergy analysis allows comparison and incroporation of environmental costs and benefits with variables of traditional economic costs and benefits to provide a more comprehensive perspective for public policy directives. Through this research, we think: 1) China has made a great effort in making Tibet develop from a closed regional system to a more and more opened regional system which is very important to the sustainable development of Tibet. 2) The increase of economic development and population growth has a close relationship with the total emergy storage and use in transportation. Education in modern science and technology increased the shared emergy of Tibetans to modern science and technology and stimulated the process of matching material and energy imports from outside with local resources. 3) There is great potential to develop hydropower and geothermal reserves that may stimulate not only economic development but also the better use of environment. 4) The better trained population can increase the empower of Tibet eco-economic system. Future development needs all kinds of talent exchanges with the outside system to develop education. 3) Compared with the Tibet economic system, Taiwan economic system is much more competitive. GNP and emergy use are very useful functions for comparing the competitive power of different ecological economic systems. 展开更多
关键词 EMERGY eco-economic evolution sustainable development
下载PDF
Degree of coupling and coordination of eco-economic system and the influencing factors: a case study in Yanchi County, Ningxia Hui Autonomous Region, China 被引量:13
11
作者 LU Huiling ZHOU Lihua +2 位作者 CHEN Yong AN Yiwei HOU Caixia 《Journal of Arid Land》 SCIE CSCD 2017年第3期446-457,共12页
Based on the statistical data, we analyzed and evaluated the degree of coupling and coordination of the eco-economic system in Yanchi County for the period spanning from 1983 to 2014. The eco-economic system can be di... Based on the statistical data, we analyzed and evaluated the degree of coupling and coordination of the eco-economic system in Yanchi County for the period spanning from 1983 to 2014. The eco-economic system can be divided into socioeconomic and ecological sub-systems and their relationship can reveal the interaction state between the two sub-systems and help the local government to establish a coordinated development mode. An index system was constructed to assess the development of the two sub-systems before the evaluation of the degree of coupling and coordination. The principal component regression analysis was adopted to quantitatively assess the influences of natural, economic and social factors on the degree of coupling and coordination of the eco-economic system. Results showed that, from 1983 to 2014, the development trends of both sub-systems were increasing with the ecological sub-system having more fluctuations. The degree of coupling and coordination of the eco-economic system in the study area increased gradually from 1983 to 2014, but experienced five different development stages from the verge of disorder to favorable coordination. The development of the local social and economic conditions was the most important factor influencing the degree of coupling and coordination. The second most important factor was the financial support from the local government. In addition, the environment protection policies also played undeniable roles. Due to the diversity of the influence factors, the government should take comprehensive measures to promote the sustainable development of the eco-economic system. 展开更多
关键词 degree of coupling and coordination eco-economic system ecological sub-system socioeconomic sub-system YanchiCounty
下载PDF
Research on Functional Characteristics of Karst Eco-economic Compound System in Guizhou Province 被引量:2
12
作者 LUO Kun-yan Xingyi Normal University for Nationalities,Xingyi 562400,China 《Asian Agricultural Research》 2011年第3期113-119,共7页
Based on the eco-economy theory,this paper analyzed the characteristics of the components of eco-economic compound system of karst region in Guizhou Province.The functional characteristics of eco-economic compound sys... Based on the eco-economy theory,this paper analyzed the characteristics of the components of eco-economic compound system of karst region in Guizhou Province.The functional characteristics of eco-economic compound system of karst region in Guizhou Province were analyzed.The functional characteristics were as follows:low biological production of Guizhou Province;weak capacity of ecosystem;slow speed of storage and accumulation of material and serious environmental pollution;low production and efficiency of energy;serious wastes of energy.On the basis of functional characteristics of eco-economic compound System in Karst region.Some views in terms of maintenance and reconstruction of compound system,were put forward,including laying stress on improving ecological system;choosing and cultivating the advanced species that suit the Karst region;improving the amount and speed of material accumulation,at the same time,introducing into advanced production technologies and management experience;reducing the energy efficiency of each section in economic system and improving the transformation efficiency of energy. 展开更多
关键词 eco-economic COMPOUND system KARST region of Guizh
下载PDF
Eco-economic control mode and benefit analysis of rock desertification region in Huajiang Karst Valley of Guizhou Province 被引量:2
13
作者 Su Weici He Tairong Teng Jianzhen 《Ecological Economy》 2006年第3期289-297,共9页
It is difficult to afforest in rock desertification region and is the key area for eco-environment treatment. To speed up the comprehensive treatment of rock desertification, several anti-rock desertification modes im... It is difficult to afforest in rock desertification region and is the key area for eco-environment treatment. To speed up the comprehensive treatment of rock desertification, several anti-rock desertification modes implemented in Dingtan region, located on the right bank of Huajiang Grand Valley in Beipanjiang Town, are introduced as examples. This paper first analyzes the natural and environmental conditions, the development of rock desertification in the Dingtan region, then the detail of the treatment modes, such as “Chinese wingleaf pricklyash – pig breeding – marsh gas” (Mode One), “amomum villosum – pig breeding – marsh gas” mode (Mode Two), “traditional grain and economic crop (corn, peanut) – amomum villosum or Chinese wingleaf pricklyash” (Mode Three), etc. The eco-economic effects, potential and shortcomings of the above mentioned modes are analyzed and compared. It is proved that Mode One and Mode Two are of good economic effect, but Mode Three of better ecological effect. Solutions to the shortcomings of the modes are also put forward. 展开更多
关键词 Rock desertification eco-economic control modes Benefit analysis Huajiang Karst Grand Valley Guizhou Province
下载PDF
Yield of Agricultural Eco-economic System in Dongting Rim
14
作者 Maozhang HOU Yulin ZHU 《Asian Agricultural Research》 2013年第10期61-67,共7页
To analyze the efficiency of the agro-ecosystem of Dongting Rim in Hunan Province,this paper adopted the emergy theory to study the agricultural output of this region during 2001 to 2010.The results showed that the va... To analyze the efficiency of the agro-ecosystem of Dongting Rim in Hunan Province,this paper adopted the emergy theory to study the agricultural output of this region during 2001 to 2010.The results showed that the value of regional agricultural emergy output increased by44.68%to(6.50 E)sej,but lower than the growth of non-agricultural industry output.Compared with 2001,the emergy output of planting industry was(4.10E)sej in 2010 which occupied 63.09%of the total agricultural emergy output and got an increase of 2.93 percentage points,while the emergy output of stock farming got a decrease of 2.87 percentage points.The growth of fishery emergy output was not in conformity with the characteristics of Dongting Rim in Hunan.From the contrast between emergy output and economic output,we could find that the economic return ratio of planting industry and fishery industry were lower than those of forestry industry and stock farming industry,which indicated that it is necessary to improve the economic benefits of planting industry and fishery industry which were the traditional industries with advantages of the Dongting Rim in Hunan. 展开更多
关键词 Dongting RIM AGRICULTURAL eco-economic SYSTEM Emer
下载PDF
Emergy Analysis of Sustainability of Eco-economic System in Sichuan's Baisha River Valley
15
作者 AN Yun 《Asian Agricultural Research》 2012年第6期66-70,共5页
Using emergy analysis method,I conduct quantitative analysis of social,economic and natural systems in Sichuan's Baisha River valley during the period 2002-2006,through the establishment of indicators.I compare th... Using emergy analysis method,I conduct quantitative analysis of social,economic and natural systems in Sichuan's Baisha River valley during the period 2002-2006,through the establishment of indicators.I compare the emergy of Baisha River valley,with that of Xinjiang's Manas River valley and Sichuan Province,and evaluate the sustainable development conditions in Baisha River valley,in order to provide corresponding reference for the development and utilization of Baisha River valley in the future.The results show that from the perspective of emergy input of economic system,Baisha River valley is a typical ecological and economic zone with rich resources to be developed;in terms of the development of natural conditions and utilization of ecological resources,the resource utilization intensity of Baisha River valley is weak and the environmental loading ratio there is low,thus the level of emergy yield needs to be improved;the system of Baisha River valley has enormous capacity for sustainable development and good potential for development. 展开更多
关键词 Baisha River valley eco-economic system Emergy analysis Sustainable development
下载PDF
Early Triassic Volcanic Rocks in the Western Yarlung Zangbo Suture Zone:Implications for the Opening of the Neo-Tethys Ocean 被引量:1
16
作者 HE Juan LI Yalin +4 位作者 HOU Yunling ZHOU Aorigele WEI Yushuai CHEN Xi DAI Jingen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期324-336,共13页
In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-... In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-NdPb isotopic data,the Early Triassic samples could be divided into two groups:Group 1 with P-MORB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70253–0.70602,ε_(Nd)(t)values of 4.2–5.3,(^(206)Pb/^(204)Pb)_(t)ratios of 16.353–18.222,(^(207)Pb/^(204)Pb)_(t)ratios of 15.454–15.564,and(^(208)Pb/^(204)Pb)_(t)ratios of 35.665–38.136;Group 2 with OIB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70249–0.70513,ε_(Nd)(t)values of 4.4–4.9,(^(206)Pb/^(204)Pb)_(t)ratios of 17.140–18.328,(^(207)Pb/^(204)Pb)_(t)ratios of 15.491–15.575,and(^(208)Pb/^(204)Pb)_(t)ratios of 36.051–38.247.Group 2 rocks formed by partial melting of the mantle source enriched by a former plume,and assimilated continental crustal material during melt ascension.The formation of Group 1 rocks corresponds to the mixing of OIB melts,with the same components as Group 2 and N-MORBs.The Zhongba Early Triassic rocks belong to the continental margin type ophiolite and formed in the continental–oceanic transition zone during the initial opening of the Neo-Tethys in southern Xizang(Tibet). 展开更多
关键词 RIFT Early Triassic magmatism Yarlung Zangbo Suture zone NEO-TETHYS Southern Xizang TIBET
下载PDF
Improving creep strength of the fine-grained heat-affected zone of novel 9Cr martensitic heat-resistant steel via modified thermo-mechanical treatment 被引量:1
17
作者 Jingwen Zhang Liming Yu +6 位作者 Yongchang Liu Ran Ding Chenxi Liu Zongqing Ma Huijun Li Qiuzhi Gao Hui Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1037-1047,共11页
The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional the... The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional thermo-mechanical treatment was modified via the replacement of hot-rolling with cold rolling,i.e.,normalizing,cold rolling,and tempering (NCT),which was developed to improve the creep strength of the FGHAZ in G115 steel weldments.The NCT treatment effectively promoted the dissolution of preformed M_(23)C_(6)particles and relieved the boundary segregation of C and Cr during welding thermal cycling,which accelerated the dispersed reprecipitation of M_(23)C_(6) particles within the fresh reaustenitized grains during post-weld heat treatment.In addition,the precipitation of Cu-rich phases and MX particles was promoted evidently due to the deformation-induced dislocations.As a result,the interacting actions between precipitates,dislocations,and boundaries during creep were reinforced considerably.Following this strategy,the creep rupture life of the FGHAZ in G115 steel weldments can be prolonged by 18.6%,which can further push the application of G115 steel in USC power plants. 展开更多
关键词 G115 steel fine-grained heat-affected zone creep strength element segregation nano-sized precipitates
下载PDF
Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances 被引量:1
18
作者 ZHOU Li WANG Guo-rong WAN Min 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期271-284,共14页
An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control... An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller. 展开更多
关键词 adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control
下载PDF
One-year results for myopia control of orthokeratology with different back optic zone diameters: a randomized trial using a novel multispectral-based topographer 被引量:1
19
作者 Wen-Ting Tang Xiang-Ning Luo +4 位作者 Wen-Jing Zhao Jia Liao Xin-Yue Xu Hui-Dan Zhang Li Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期324-330,共7页
AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in ... AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in children.METHODS:This randomized clinical study was performed between Dec.2020 and Dec.2021.Participants were randomly assigned to three groups wearing ortho-k:5 mm BOZD(5-MM group),5.5 mm BOZD(5.5-MM group),and 6 mm BOZD(6-MM group).The 1-year data were recorded,including axial length,relative peripheral refraction(RPR,measured by multispectral refractive topography,MRT),and visual quality.The contrast sensitivity(CS)was evaluated by CSV-1000 instrument with spatial frequencies of 3,6,12,and 18 cycles/degree(c/d);the corneal higher-order aberrations(HOAs)were measured by iTrace aberration analyzer.The one-way ANOVA was performed to assess the differences between the three groups.The correlation between the change in AL and RPR was calculated by Pearson’s correlation coefficient.RESULTS:The 1-year results of 20,21,and 21 subjects in the 5-MM,5.5-MM,and 6-MM groups,respectively,were presented.There were no statistical differences in baseline age,sex,or ocular parameters between the three groups(all P>0.05).At the 1-year visit,the 5-MM group had lower axial elongation than the 6-MM group(0.07±0.09 vs 0.18±0.11 mm,P=0.001).The 5-MM group had more myopic total RPR(TRPR,P=0.014),with RPR in the 15°–30°(RPR 15–30,P=0.015),30°–45°(RPR 30–45,P=0.011),temporal(RPR-T,P=0.008),and nasal area(RPR-N,P<0.001)than the 6-MM group.RPR 15–30 in the 5.5-MM group was more myopic than that in the 6-MM group(P=0.002),and RPR-N in the 5-MM group was more myopic than that in the 5.5-MM group(P<0.001).There were positive correlations between the axial elongation and the change in TRPR(r=0.756,P<0.001),RPR 15–30(r=0.364,P=0.004),RPR 30–45(r=0.306,P=0.016),and RPR-N(r=0.253,P=0.047).The CS decreased at 3 c/d(P<0.001),and the corneal HOAs increased in the 5-MM group(P=0.030).CONCLUSION:Ortho-k with 5 mm BOZD can control myopia progression more effectively.The mechanism may be associated with greater myopic shifts in RPR. 展开更多
关键词 relative peripheral refraction ORTHOKERATOLOGY MYOPIA back optic zone diameter axial length multispectral refractive topography
下载PDF
The Influence of the Closure of the East Paleo-Tethys Ocean on Southern South China:Evidences from Kinematics and^(40)Ar/^(39)Ar Geochronology of the Rongxian Ductile Shear Zone in Southeastern Guangxi 被引量:1
20
作者 HUANG Wenqiang LI Saisai +5 位作者 XIN Liangwei FENG Zuohai ZHANG Hongrui GENG Jieli LIU Kun SHI Chunyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1125-1140,共16页
The Triassic was a crucial period in the tectonic evolution of the South China Block.Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China.In t... The Triassic was a crucial period in the tectonic evolution of the South China Block.Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China.In this study,alongside thermochronological analyses,we examine the macroscopic and microscopic structural features of the Rongxian ductile shear zone,located south of the Darongshan granite in the southeastern part of Guangxi Province,on the southern margin of South China.Sinistral shear is indicated by the characteristics of rotatedσ-type feldspar porphyroclasts,stretching lineations defined by elongated quartz grains and the orientations of quartz c-axes.LA-ICP-MS U-Pb dating of zircons from two samples of granitic mylonite and one of granite yielded ages of ca.256 Ma.Furthermore,two samples of granitic mylonite yield muscovite^(40)Ar/^(39)Ar plateau ages of 249-246 Ma.These results indicate that the Rongxian ductile shear zone resulted from Early Triassic deformation of the late Permian Darongshan granite.This deformation was likely related to the closure of the eastern Paleo-Tethys Ocean and the subsequent collision of the South China and Indochina blocks,during the early stage of the Indosinian orogeny. 展开更多
关键词 ductile shear zone ^(40)Ar/^(39)Ar geochronology TRIASSIC South China Block East Paleo-Tethys Ocean
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部