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Conservation and Utilization Status and Development Strategies of Livestock and Poultry Germplasm Resources in Binzhou City
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作者 Lu GUO Shijin GUO +9 位作者 Jingjing SONG Shijun FU Xiaoliang WANG Jian ZHAO Lu LIU Xiaolu ZHAO Zhen LIU Xin LI Yanling REN Wenjian MA 《Agricultural Biotechnology》 2025年第2期29-33,53,共6页
This paper investigated and analyzed the conservation and utilization of four local livestock breeds in Binzhou City:Wadi Sheep,Bohai Black Cattle,Wudi Donkey,and Lubei White Goat.Shortcomings in the protection and ut... This paper investigated and analyzed the conservation and utilization of four local livestock breeds in Binzhou City:Wadi Sheep,Bohai Black Cattle,Wudi Donkey,and Lubei White Goat.Shortcomings in the protection and utilization of local germplasm resources were pointed out,and strategies and recommendations were proposed to promote high-quality development of livestock and poultry genetic resources in Binzhou,including building a solid germplasm foundation,standardizing production,and driving innovation.This paper provides references for the conservation,development,and utilization of local genetic resources in Binzhou City. 展开更多
关键词 Livestock and poultry Germplasm resource Protection and utilization Present situation development strategy
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"Three-in-One" Ecological Development and Efficient Utilization Model of Aggregates
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作者 Yunkai FAN Shichang XU +2 位作者 Qiangjie HUANG Yiyuan LU Ziyi WEI 《Asian Agricultural Research》 2024年第6期13-18,共6页
Green mining and the formation of an effective and efficient development model have become key issues that aggregates enterprises around the world need to solve urgently.On the basis of analyzing the development statu... Green mining and the formation of an effective and efficient development model have become key issues that aggregates enterprises around the world need to solve urgently.On the basis of analyzing the development status of aggregates industry in Xiluodu area,the paper studied the main problems faced in the construction of green aggregates mines at present,and proposed a"three-in-one"ecological,intelligent and efficient green mine construction model for"ecological development","green logistics"and"solid waste recycling"of aggregates.The study has certain theoretical value and practical significance for the construction of green aggregates mine in Xiluodu area. 展开更多
关键词 AGGREGATES ECOLOGICAL development EFFICIENT utilization
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Determining the Prevailing Effects among Public Space Utilization Factors in Science Cities:A Study in Cyberjaya,Malaysia
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作者 Oloruntoba Kayode 《Journal of Civil Engineering and Architecture》 2025年第4期173-183,共11页
The aim of this study is to develop an understanding on the contributing influences that occur among qualities of public space,public space aesthetics,the comfort derived in public space and public space accessibility... The aim of this study is to develop an understanding on the contributing influences that occur among qualities of public space,public space aesthetics,the comfort derived in public space and public space accessibility in science cities.This study seeks to investigate the extent at which public space attributes impact on one another.The emphasis accruing to open greenery including public spaces in the physical development of science cities necessitates the selection of Cyberjaya Malaysia as the study area.Survey questionnaires were used to investigate potential respondent’s perceptions on public space utilization and the feedback was validated with SEM(structural equation modelling).The findings indicated that the accessibility attributes significantly influenced other public space utilization attributes while good quality of public space influenced the comfort derived from it.Attractiveness of public space was found not capable to predict the comfort and good quality of public space. 展开更多
关键词 Public space science city physical development utilization relationship
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Strategic Tasks of Land Resource Development in Mountainous Areas of China
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作者 Mingling YAO Yimei HE +1 位作者 Shiqin YANG Fuluan YANG 《Asian Agricultural Research》 2025年第6期13-19,共7页
This paper first analyzes the fundamental characteristics and the advantages and disadvantages in the development and utilization of land resources in China s mountainous areas. It then explores the five major strateg... This paper first analyzes the fundamental characteristics and the advantages and disadvantages in the development and utilization of land resources in China s mountainous areas. It then explores the five major strategic tasks facing the sustainable development and utilization of mountainous land resources in China. From the perspective of human-land coordination and sustainable development, the paper proposes countermeasures and recommendations for the sustainable development and utilization of land resources in China s mountainous areas. 展开更多
关键词 Mountainous areas development of land resources Strategic tasks Sustainable utilization of land
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Technology and understanding of post-fracturing coring in three-dimensional development zone of Fuling shale gas,Sichuan Basin,SW China
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作者 SUN Huanquan LU Zhiyong +5 位作者 LIU Li FANG Jichao ZHENG Aiwei LI Jiqing ZHANG Yuqiang XIAO Jialin 《Petroleum Exploration and Development》 2025年第3期731-745,共15页
The core sampling experiments were conducted after hydraulic fracturing in the three-dimensional development zone of Fuling shale gas.Six coring wells of different well types were systematically designed.Based on the ... The core sampling experiments were conducted after hydraulic fracturing in the three-dimensional development zone of Fuling shale gas.Six coring wells of different well types were systematically designed.Based on the integrated engineering technology of post-fracturing drilling,coring and monitoring of shale and the analysis of fracture source tracing,the evaluation of the fracture network after fracturing in the three-dimensional development of shale gas was conducted.The data of core fractures after fracturing indicate that three major types of fractures are formed after fracturing:natural fractures,hydraulic fractures,and fractures induced by external mechanical force,which are further classified into six subcategories:natural structural fractures,natural bedding fractures,hydraulic fractures,hydraulically activated fractures,drilling induced fractures,and fractures induced by core transportation.The forms of the artificial fracture network after fracturing are complex.Hydraulic fractures and hydraulically activated fractures interweave with each other,presenting eight forms of artificial fracture networks,among which the“一”-shaped fracture is the most common,accounting for approximately 70%of the total fractures.When the distance to the fractured wellbore is less than 35 m,the density of the artificial fracture network is relatively high;when it is 35–100 m,the density is lower;and when it is beyond 100 m,the density gradually increases.The results of the fracture tracing in the core sampling area confirm that the current fracturing technology can essentially achieve the differential transformation of the reservoir in the main area of Jiaoshiba block in Fuling.The three-layer three-dimensional development model can efficiently utilize shale gas reserves,although there is still room for improvement in the complexity and propagation uniformity of fractures.It is necessary to further optimize technologies such as close-cutting combined with temporary blocking and deflection within fractures or at fracture mouths,as well as limited flow perforation techniques,to promote the balanced initiation and extension of fractures. 展开更多
关键词 Fuling shale gas field three-dimensional development post-fracturing core sampling coring technology fracture classification fracture source tracing fracture network assessment reserve utilization
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Research Progress on the Development and Utilization of Proteins in Edible Insects
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作者 冉文波 赵晨霞 《Agricultural Science & Technology》 CAS 2014年第4期683-687,共5页
The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as t... The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as the main development direc- tion of edible insect proteins. And we also pointed out the bottlenecks that restricted the development and utilization of proteins in edible insects, and proposed the prospect of the research, development and utilization of edible insects proteins. 展开更多
关键词 Edible insects PROTEIN Research progress development and utilization
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Development and Utilization of the World's and China's Bulk Mineral Resources and their Supply and Demand Situation in the Next Twenty Years 被引量:9
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作者 ZHANG Zhaozhi JIANG Guangyu +1 位作者 WANG Xianwei ZHANG Jianfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第4期1370-1417,共48页
Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world's and China's economic development. This study analyzed and predicted their resourc... Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world's and China's economic development. This study analyzed and predicted their resources base and potential, development and utilization and their world's and China's supply and demand situation in the future 20 years. The supply and demand of these six bulk mineral products are generally balanced, with a slight surplus, which will guarantee the stability of the international mineral commodity market supply. The six mineral resources (especially iron ores and copper ores) are abundant and have a great potential, and their development and utilization scale will gradually increase. Till the end of 2014, the reserve- production ratio of iron, copper, bauxite, lead, zinc ores and potassium salt was 95 years, 42 years, 100 years, 17 years, 37 years and 170 years, respectively. Except lead ores, the other five types all have reserve-production ratio exceeding 20 years, indicative of a high resources guarantee degree. If the utilization of recycled metals is counted in, the supply of the world's six mineral products will exceed the demand in the future twenty years. In 2015-2035, the supply of iron ores, refined copper, primary aluminum, refined lead, zinc and potassium salt will exceed their demand by 0.4-0.7 billion tons (Gt), 5.0-6.0 million tons (Mt), 1.1-8.9 Mt, 1.0-2.0 Mt, 1.2-2.0 Mt and 4.8-5.6 Mt, respectively. It is predicted that there is no problem with the supply side of bulk mineral products such as iron ores, but local or structural shortage may occur because of geopolitics, monopoly control, resources nationalism and trade friction. Affected by China's compressed industrialized development model, the demand of iron ores (crude steel), potassium salt, refined lead, refined copper, bauxite (primary aluminum) and zinc will gradually reach their peak in advance. The demand peak of iron ores (crude steel) will reach around 2015, 2016 for potassium salt, 2020 for refined lead, 2021 for bauxite (primary aluminum), 2022 for refined copper and 2023 for zinc. China's demand for iron ores (crude steel), bauxite (primary aluminum) and zinc in the future 20 years will decline among the world's demand, while that for refined copper, refined lead and potassium salt will slightly increase. The demand for bulk mineral products still remains high. In 2015-2035, China's accumulative demand for iron ores (crude steel) will be 20.313 Gt (13.429 Gt), 0.304 Gt for refined copper, 2.466 Gt (0.616 Gt) of bauxite (primary aluminum), 0.102 Gt of refined lead, 0.138 Gt of zinc and 0.157 Gt of potassium salt, and they account for the world's YOY (YOY) accumulative demand of 35.17%, 51.09%, 48.47%, 46.62%, 43.95% and 21.84%, respectively. This proportion is 49.40%, 102.52%, 87.44%, 105.65%, 93.62% and 106.49% of that in 2014, respectively. From the supply side of China's bulk mineral resources, it is forecasted that the accumulative supply of primary (mine) mineral products in 2015-2035 is 4.046 Gt of iron ores, 0.591 Gt of copper, 1.129 Gt of bauxite, 63.661 Mt of (mine) lead, 0.109 Gt of (mine) zinc and 0.128 Gt of potassium salt, which accounts for 8.82%, 13.92%, 26.67%, 47.09%, 33.04% and 15.56% of the world's predicted YOY production, respectively. With the rapid increase in the smelting capacity of iron and steel and alumina, the rate of capacity utilization for crude steel, refined copper, alumina, primary aluminum and refined lead in 2014 was 72.13%, 83.63%, 74.45%, 70.76% and 72.22%, respectively. During 2000-2014, the rate of capacity utilization for China's crude steel and refined copper showed a generally fluctuating decrease, which leads to an insufficient supply of primary mineral products. It is forecasted that the supply insufficiency of iron ores in 2015-2035 is 17.44 Gt, 0.245 Gt of copper in copper concentrates, 1.337 Gt of bauxite, 38.44 Mt of lead in lead concentrates and 29.19 Mt of zinc in zinc concentrates. China has gradually raised the utilization of recycled metals, which has mitigated the insufficient supply of primary metal products to some extent. It is forecasted that in 2015-2035 the accumulative utilization amount of steel scrap (iron ores) is 3.27 Gt (5.08 Gt), 70.312 Mt of recycled copper, 0.2 Gt of recycled aluminum, 48 Mt of recycled lead and 7.7 Mt of recycled zinc. The analysis on the supply and demand situation of China's bulk mineral resources in 2015-2035 suggests that the supply-demand contradiction for these six types of mineral products will decrease, indicative of a generally declining external dependency. If the use of recycled metal amount is counted in, the external dependency of China's iron, copper, bauxite, lead, zinc and potassium salt will be 79%, 65%, 26%, 8%, 16% and 18% in 2014, respectively. It is predicted that this external dependency will decrease to 62%, 64%, 20%, -0.93%, 16% and 14% in 2020, respectively, showing an overall decreasing trend. We propose the following suggestions correspondingly. (1) The demand peak of China's crude steel and potassium salt will reach during 2015-2023 in succession. Mining transformation should be planned and deployed in advance to deal with the arrival of this demand peak. (2) The supply-demand contradiction of China's bulk mineral resources will mitigate in the future 20 years, and the external dependency will decrease accordingly. It is suggested to adjust the mineral resources management policies according to different minerals and regions, and regulate the exploration and development activities. (3) China should further establish and improve the forced mechanism of resolving the smelting overcapacity of steel, refined copper, primary aluminum, lead and zinc to really achieve the goal of "reducing excess production capacity". (4) In accordance with the national strategic deployment of "One Belt One Road", China should encourage the excess capacity of steel, copper, alumina and primary aluminum enterprises to transfer to those countries or areas with abundant resources, high energy matching degree and relatively excellent infrastructure. Based on the national conditions, mining condition and geopolitics of the resources countries, we will gradually build steel, copper, aluminum and lead-zinc smelting bases, and potash processing and production bases, which will promote the excess capacity to transfer to the overseas orderly. (5) It is proposed to strengthen the planning and management of renewable resources recycling and to construct industrial base of renewable metal recycling. (6) China should promote the comprehensive development and utilization of paragenetic and associated mineral species to further improve the comprehensive utilization of bulk mineral resources. 展开更多
关键词 China bulk scarce mineral resource development and utilization demand prediction supply and demand analysis reducing excess production capacity
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Harmonious Development of Utilization and Protection of Tidal Flats and Wetlands-A Case Study in Shanghai Area 被引量:4
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作者 陈吉余 程和琴 +1 位作者 戴志军 Doeke EISMA 《China Ocean Engineering》 SCIE EI 2008年第4期649-662,共14页
Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal... Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal flat is defined, and its spatial limitation is also clarified. Located at the Yangtze Estuary, tidal flats in Shanghai area are selected for study. The relationship between water discharge and sediment transport of the Yangtze River, allowed exploration intensity and needs for wetland protection are discussed in the paper. The dynamic process and changing trend for different types of tidal flats are illustrated in detail. Regulations are proposed for a reasonable exploitation, dynamic protection, and ecosystem restoration of each individual tidal fiat and wetland. Some valuable suggestions are put forward for further study about the sustain'able exploitation of offshore resources in Shanghai area. 展开更多
关键词 Shanghai area harmarious development utilization PROTECTION tidal fiat WETLAND
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Development and Utilization of Saline Lake Resources and Protection of Ecological Environment in Qaidam Basin in Qinghai Province 被引量:3
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作者 MENG Wei SHU Jianmin +1 位作者 YANG Rongjin LI Yanwu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期191-193,共3页
Qaidam basin is an important part of National Key Development Area–Lanzhou-Xining Area,is a key region of resource development in Western Development,is a National Circular Economy Pilot Zone.The focus of
关键词 saline lake resources development and utilization protection of ecological environment Qaidam Basin.
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Urban development and resource endowments shape natural resource utilization efficiency in Chinese cities 被引量:4
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作者 Yanbing Liu Fei Lu +1 位作者 Chaofan Xian Zhiyun Ouyang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第4期806-816,共11页
Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, w... Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, we established a comprehensive natural resource utilization efficiency index(NRUEI). We then calculated the 2016 index for 165 cities in China,and investigated what caused it to vary. We found three main results:(1) the NRUEI varied greatly across China and there were significant positive correlations between urban energy utilization efficiency(EUE), water utilization efficiency(WUE) and land utilization efficiency(LUE);(2) the NRUEI showed a significant positive correlation with a city’s population size,economy(Gross Domestic Product(GDP)), and the level of urban social development(GDP per capita);(3) cities in East China have the highest natural resource utilization efficiency,while cities in Northeast China have the lowest. These results indicate that China’s increasing urban development is associated with rising natural resource utilization efficiency and that the city’s endowment of natural resources is an important factor affecting that efficiency. Further, the results showed that the determinants of a city’s NRUEI differed in large and small cities. Lastly, our results suggest that improving EUE is key for improving NRUEI in urban China, and different efficiencies can be improved intertwined. A major takeaway of this study is that there is great potential for improving natural resource utilization efficiency in Chinese cities and we include city-specific suggestions for efficiency improvements. 展开更多
关键词 Urban development Resource endowment Resource utilization efficiency Sustainable city
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Effect of dietary calcium or phosphorus deficiency on bone development and related calcium or phosphorus metabolic utilization parameters of broilers from 22 to 42 days of age 被引量:2
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作者 YANG Yun-feng XING Guan-zhong +5 位作者 LI Su-fen SHAO Yu-xin ZHANG Li-yang LU Lin LUO Xugang LIAO Xiu-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第11期2775-2783,共9页
This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age b... This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study,which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age.A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design,and fed the normal control and Ca-or P-deficient diets from 1 to 21 days of age.At 22 days of age,the broilers were further fed the normal control diet(0.90%Ca+0.35%non-phytate P(NPP)),the P-deficient diet(0.90%Ca+0.18%NPP),the Ca-deficient diet(0.30%Ca+0.35%NPP)or the Ca and P-deficient diet(0.30%Ca+0.18%NPP),respectively.The results showed that dietary Ca or P deficiency decreased(P<0.05)tibia bone mineral density(BMD),bone breaking strength(BBS),ash content,tibia ash Ca content and serum P content on days 28 and 42,but increased(P<0.05)tibia alkaline phosphatase(ALP)activity of broilers on day 42 compared with the control group.Furthermore,the broilers fed the P-deficient diet had the lowest(P<0.05)tibia BMD,BBS,ash content,serum P content and the highest(P<0.05)serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets.The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency,followed by dietary Ca deficiency or Ca and P-deficiency;dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age. 展开更多
关键词 calcium deficiency phosphorus deficiency bone development metabolic utilization parameter BROILER
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THE UTILIZATION OF WATER RESOURCE AND THE OASIS ECONOMIC DEVELOPMENT IN ARID LAND—A CASE STUDY OF TURPAN BASIN 被引量:1
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作者 Fu Xiaofeng Department of Urban and Resource Sciences, Nanjing University, Nanjing 210093 People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第2期60-68,共9页
Turpan Basin is a unique geographic region in China. The topography of the Basin is closed and the climate is extremely dry. The shortage of water resource has been restricting the existence and development of the oas... Turpan Basin is a unique geographic region in China. The topography of the Basin is closed and the climate is extremely dry. The shortage of water resource has been restricting the existence and development of the oasis in Turpan Basin. This paper briefly analyzes the characteristics of the basin's water resources, and expounds the processes of their utilization and regional development. It points out that the exploration of water resource is close to the limit and the utilization of water resource is unreasonable. So it is nonrealistic to follow the traditional exploration pattern. According to the transforming pattern between runoff and groundwater in the basin, an overall planning of the utilization of the water resource is advanced. Based on the relation between the maintenance of Aydingkol Lake and the existence of the oasis, the amount of water resource used must be controlled in order to guarantee the existence of the lake. The orientation of the utilization of water resource is to improve the management level of water resource, and to apply advanced water saving technology. Building up an economic system which can effectively use water resource is the orientation of the oasis sustainable economic development. 展开更多
关键词 Turpan Basin water resource utilization oasis economic development.
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Development and Utilization of Rural Idle Homesteads in the Context of Rural Revitalization——A Case Study of Leisure Agriculture 被引量:1
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作者 Dingpu LIU 《Asian Agricultural Research》 2019年第2期53-56,共4页
The existence of a large number of idle homesteads in rural areas not only causes waste of land resources,but also injures farmers' property rights and hinders the implementation of rural revitalization strategy. ... The existence of a large number of idle homesteads in rural areas not only causes waste of land resources,but also injures farmers' property rights and hinders the implementation of rural revitalization strategy. The emergence and vigorous development of rural leisure agriculture provides a new way of utilization and method for the development and utilization of rural homesteads. From the perspective of leisure agriculture,this paper analyzed the characteristics,advantages and disadvantages of the overall development model of rural idle homestead,farmstay model and characteristic industry development model,and discussed the actual case to enrich the research on the development and utilization of idle homestead. It pointed out that there are problems such as insufficient tourism resources and single management content,lack of legal basis for revitalizing the homestead,lagging reform of rural land property rights system,and difficulty in expanding the space for leisure tourism development in the process of developing rural idle homestead. It is recommended to provide reference for the effective improvement of the efficiency of idle homestead utilization,increase farmers' income,and promote the rural revitalization strategy. 展开更多
关键词 RURAL REVITALIZATION RURAL IDLE HOMESTEAD development and utilization LEISURE agriculture
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Beneficial effects of a decreased meal frequency on nutrient utilization,secretion of luteinizing hormones and ovarian follicular development in gilts 被引量:1
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作者 Lun Hua Lianpeng Zhao +10 位作者 Zhengyu Mao Wentao Li Jing Li Xuemei Jiang Lianqiang Che Shengyu Xu Yan Lin Zhengfeng Fang Bin Feng De Wu Yong Zhuo 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第3期1098-1111,共14页
Background:Replacement gilts are typically fed ad libitum,whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits.The objective of this study was to... Background:Replacement gilts are typically fed ad libitum,whereas emerging evidence from human and rodent studies has revealed that time-restricted access to food has health benefits.The objective of this study was to investigate the effect of meal frequency on the metabolic status and ovarian follicular development in gilts.Methods:A total of 36 gilts(Landrace×Yorkshire)with an age of 150±3 d and a body weight of 77.6±3.8 kg were randomly allocated into one of three groups(n=12 in each group),and based on the group allocation,the gilts were fed at a frequency of one meal(T1),two meals(T2),or six meals per day(T6)for 14 consecutive weeks.The effects of the meal frequency on growth preference,nutrient utilization,short-chain fatty acid production by gut microbial,the post-meal dynamics in the metabolic status,reproductive hormone secretions,and ovarian follicular development in the gilts were measured.Results:The gilts in the T1 group presented a higher average daily gain(+48 g/d,P<0.05)and a higher body weight(+4.9 kg,P<0.05)than those in the T6 group.The meal frequency had no effect on the apparent digestibility of dry matter,crude protein,ether extract,ash,and gross energy,with the exception that the T1 gilts exhibited a greater NDF digestibility than the T6 gilts(P<0.05).The nitrogen balance analysis revealed that the T1 gilts presented decreased urine excretion of nitrogen(−8.17 g/d,P<0.05)and higher nitrogen retention(+9.81 g/d,P<0.05),and thus exhibited higher nitrogen utilization than the T6 gilts.The time-course dynamics of glucose,α-amino nitrogen,urea,lactate,and insulin levels in serum revealed that the T1 group exhibited higher utilization of nutrients after a meal than the T2 or T6 gilts.The T1 gilts also had a higher acetate content and SCFAs in feces than the T6 gilts(P<0.05).The age,body weight and backfat thickness of the gilts at first estrous expression were not affected by the meal frequency,but the gilts in the T1 group had higher levels of serum luteinizing hormone on the 18th day of the 3rd estrus cycle and 17β-estradiol,a larger number of growing follicles and corpora lutea,and higher mRNA expression levels of genes related to follicular development on the 19th day of the 3rd estrus cycle.Conclusions:The current findings revealed the benefits of a lower meal frequency equal feed intake on nutrient utilization and reproductive function in replacement gilts,and thus provide new insights into the nutritional strategy for replacement gilts,and the dietary pattern for other mammals,such as humans. 展开更多
关键词 GILTS Luteinizing hormone Meal frequency Nutrient utilization Ovarian follicular development
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Priority-sequence of mineral resources' development and utilization based on grey relational analysis method 被引量:3
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作者 Wang Ying Zhang Chang Jiang Gaopeng 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第3期395-400,共6页
Generally, the sequence decision of the development and utilization of Chinese mineral resources is based on national and provincial overall plan of the mineral resources. Such plan usually cannot reflect the relative... Generally, the sequence decision of the development and utilization of Chinese mineral resources is based on national and provincial overall plan of the mineral resources. Such plan usually cannot reflect the relative size of the suitability of the development and utilization of mineral resources. To solve the problem, the paper has selected the gift condition, the market condition, the technological condition,socio-economic condition and environmental condition as the starting-points to analyze the influential factors of the priority-sequence of mineral resources' development and utilization. The above 5 conditions are further specified into 9 evaluative indicators to establish an evaluation indicator system. At last,we propose a decision model of the priority sequence based on grey relational analysis method, and figure out the observation objects by the suitability index of development. Finally, the mineral resources of a certain province in China were analyzed as an example. The calculation results indicate that silver(2.0057), coal(1.9955), zinc(1.9442), cement limestone(1.9077), solvent limestone(1.5624) and other minerals in the province are suitable for development and utilization. 展开更多
关键词 Mineral resources development and utilization Priority-sequence Grey relational analysis method
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Status and Development of Natural Gas Utilization in China 被引量:1
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作者 Wu Kangyu and Ma An(China National Petroleum Corp.) 《China Oil & Gas》 CAS 1995年第2期7-9,共3页
StatusandDevelopmentofNaturalGasUtilizationinChina¥WuKangyuandMaAn(ChinaNationalPetroleumCorp.)Keywords:Natu... StatusandDevelopmentofNaturalGasUtilizationinChina¥WuKangyuandMaAn(ChinaNationalPetroleumCorp.)Keywords:Naturalgasutilization... 展开更多
关键词 NATURAL GAS utilization DEVELOPING TREND STATUS quo
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Further development and sustainable utilization mode of grassland tourism resources: a case study of Inner Mongolia Autonomous Region, China 被引量:3
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作者 Liu Min Liu Aili Chen Tian 《Ecological Economy》 2007年第2期190-201,共12页
Tourism resources are important foundation for the development of tourism industry.Grassland is not only a kind of important resource but also a great attraction to visitors.Therefore,the integrated development and su... Tourism resources are important foundation for the development of tourism industry.Grassland is not only a kind of important resource but also a great attraction to visitors.Therefore,the integrated development and sustainable utilization of grassland tourism resources are of great significance.This paper,based on the analysis of literatures and the current problems existing in grassland tourism,summarizes the speciality of grassland tourism development,deals nation as example and carries out empirical research.Based on the status quo of grassland tourism resources in Inner Mongolia,this study analyzes the characteristics of grassland tourism resources,the necessity and feasibility of integrated development,then proposes the following suggestions: idea for development,mode of development,regional cooperation,tourism products development,especially the three modes of development based on the resources conditions - the mode of relying on market,the mode of combination aggregation and the mode of relying on quality. 展开更多
关键词 Grassland tourism resources Integrated development Sustainable utilization Inner Mongolia autonomous region
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“Extreme utilization”development theory of unconventional natural gas 被引量:1
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作者 MA Xinhua 《Petroleum Exploration and Development》 CSCD 2021年第2期381-394,共14页
In the process of unconventional natural gas development practice,the"extreme utilization"concept that focuses on"continuously breaking through the limit of development technology"is gradually form... In the process of unconventional natural gas development practice,the"extreme utilization"concept that focuses on"continuously breaking through the limit of development technology"is gradually formed,and supports the scale benefit exploration of unconventional gas in China.On this basis,the development theory of"extreme utilization"is proposed,its theoretical connotation together with development technologies of unconventional natural gas are clarified.The theoretical connotation is that,aiming at"extreme gas reservoirs","extreme techniques"are utilized to build subsurface connected bodies,expand the discharge area,and enlarge the production range,to obtain the maximum single-well production,extreme recovery,and eventually achieve the"extreme effect"of production.The series of development technologies include micro/nano-scale reservoir evaluation,"sweet spot"prediction,unconventional percolation theory and production capacity evaluation,optimization of grid well pattern,optimal-fast drilling and volume fracturing,and working regulation optimization and"integrated"organizing system.The"extreme utilization"development theory has been successfully applied in the development of unconventional gas reservoirs such as Sulige tight gas,South Sichuan shale gas,and Qinshui coalbed methane.Such practices demonstrate that,the"extreme utilization"development theory has effectively promoted the development of unconventional gas industry in China,and can provide theoretical guidance for effective development of other potential unconventional and difficult-to-recovery resources. 展开更多
关键词 unconventional natural gas extreme gas reservoir extreme development theory of extreme utilization subsurface connected body production capacity evaluation grid well pattern drainage and extraction optimization
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UTILIZATION AND SUSTAINABLE DEVELOPMENT OF ISLAND MOUNTAINS IN CHINA
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作者 张耀光 杨荫凯 《Chinese Geographical Science》 SCIE CSCD 1998年第1期59-67,共0页
The island mountain utilization is a kind of mountain utilization. Although the islands cover little area, they can be used as the base of marine development. The sustainable development of island mountains is of sign... The island mountain utilization is a kind of mountain utilization. Although the islands cover little area, they can be used as the base of marine development. The sustainable development of island mountains is of significance to marine development. There are more than 6500 islands (including the South China Sea Islets) in China, and most of them are continental islands which are the extension of continental mountains extent towards sea. For this reason, there are many hills but few mountains, the area of hills makes up more than two thirds of the whole land area. In order to keep ecological balance of islands, the utilization of island hills and mountains should take exploitation of forests as the main to conserve water source and water soil, and forests become an important factor in keeping ecological balance and sustainable development of islands. At the same time we should make good use of forests through setting up forest nature protecting area and forest parks and developing forest tourism. 展开更多
关键词 ISLANDS in China ISLAND MOUNTAINS mountain utilization SUSTAINABLE development
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Research and practice of key technologies for landslide dam development and utilization——A case in Hongshiyan landslide Dam Water Conservancy Project 被引量:2
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作者 Zongliang Zhang Xueming Wu +8 位作者 Enshang Xiao Ning He Kai Cheng Ga Zhang Xingbo Zhou Chun Zhao Huanling Wang Hongming Du Xiangang Jiang 《River》 2023年第3期251-262,共12页
Based on the emergency rescue,the subsequent disposal,and the development and utilization projects of the Hongshiyan Landside Dam in Ludian,Yunnan,China,research has been conducted on key technical issues facing the d... Based on the emergency rescue,the subsequent disposal,and the development and utilization projects of the Hongshiyan Landside Dam in Ludian,Yunnan,China,research has been conducted on key technical issues facing the development and utilization of landside dams,including the possibilty evaluation of development and utilization,structure analysis of wide gradation material,performance evaluation,investigation and design,dam seepage control,construction technology and equipment,and safe operation assessment.And innovative results has made in all seven aspects mentioned above,writing the history in thisfield.The achievements were directly applied to the development planning,investigation and design,construction,and operation and maintenance of the Hongshiyan Landside Dam,a comprehensive water conservancy project that integratesflood control,water supply,irrigation,and power generation,with significant comprehensive benefits. 展开更多
关键词 construction equipment development and utilization investigation and design landside dam performance evaluation safety assessment
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