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Study on Differences in Procyanidine Content Between Muscat Hamburg Grape From Different Producing Areas 被引量:1
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作者 Wen XU Qiusheng CHEN +4 位作者 Zhe YANG Qiang ZHANG Rui SUN Fang SU Yi PEI 《Agricultural Biotechnology》 CAS 2019年第1期176-179,共4页
[Objectives] This study was conducted to analyze the differences in procyanidine content in grapes caused by different producing areas. [Methods]With Muscat Hamburg grape from different producing areas as an experimen... [Objectives] This study was conducted to analyze the differences in procyanidine content in grapes caused by different producing areas. [Methods]With Muscat Hamburg grape from different producing areas as an experimental material,procyanidine content was determined by n-butanol-hydrochloric acid colorimetry. [Results] The procyanidins contents in different parts of the same variety ranked as grape seed > grape skin > grape flesh. The procyanidins contents in grapes from different producing areas were in order of Changli County,Hebei Province > Dazeshan Town,Shandong Province > Hangu District,Tianjin City.[Conclusions]The procyanidins contents in Muscat Hamburg grapes from different producing areas differ to a certain degree. 展开更多
关键词 Muscat Hamburg GRAPE PRODUCTION areas PROANTHOCYANIDINS differences
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SUSTAINABLE URBAN-RURAL RELATION IN RAPID URBANIZATION AREAS——Case of Transformation of "Urban Village" in Guangzhou
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作者 WEI Li-hua YAN Xiao-pei 《Chinese Geographical Science》 SCIE CSCD 2005年第3期212-218,共7页
Many studies have been made concerning the problems, characteristics, formation, transformation measures, etc. of urban village from sociology, urban planning and geography, etc., which have made insightful analysis. ... Many studies have been made concerning the problems, characteristics, formation, transformation measures, etc. of urban village from sociology, urban planning and geography, etc., which have made insightful analysis. However, most of these studies started mainly from the standpoint of the city govemment, drumming for the land- scape-oriented urbanization, namely pulling-down the urban village and constructing the splendid residence or business buildings. The article maintains that the most important thing the city government should do is to pay much attention to the sustainable living of urban villagers, who would lose their main income source, namely, the collective dividend and the family housing rent. The single method of compensation has been proved to be harmful to the villagers' community, in which some young villagers relying on rent were no longer to do anything but stay at home. On the other hand, considering the floating population has become the main stream of renters in urban villages, the emergence of urban villages was inevitable and would continue to exist in a long time under the socio-economic transition in urban China and globalization. Based on the analysis above, the transformation of urban village should take more concerns on the housing demands of floating population besides compensation for local villagers. Meanwhile, it is necessary to avoid the “landscape-oriented urbanization” without the “peasant-to-citizen” transformation. 展开更多
关键词 urban-rural relation rapid urbanization areas GUANGZHOU urban village
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The Exploration to the Historical Origin of Differences between Urban and Rural Areas in China
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作者 ZHU Hong-liang ZHANG Rui-qing 《Asian Agricultural Research》 2011年第1期118-121,126,共5页
In order to understand the historical origins of encircling the cities from the rural areas implemented by the Communist Party of China and the current dual structures of urban and rural development, urban-rural diffe... In order to understand the historical origins of encircling the cities from the rural areas implemented by the Communist Party of China and the current dual structures of urban and rural development, urban-rural differences are analyzed from the four aspects of production mode, management mode, culture and social division of labor. Industrial development in modern times has promoted the modernization of urban production in China. But the rural areas still maintain their traditional self-sufficient natural economy. After the Opium War, the process of modernization of city politics is promoted by more economic elements of capitalism and the formation of Chinese bourgeoisie. During the management of urban modernization, rural areas still adopt the traditional self-management mode. In the aspect of culture, city is the center of development, having large population, developed traffic, and prosperous culture. But the village is lack of information and its culture is relatively backward. In modern times, affected by the foreign capitalist, urban area has become the center of modern productivity. After separating from agriculture, handicraft industry has transferred into urban areas and the social division of labor in both urban and rural areas has shown great changes. Thus, a new pattern of "Urban Industry, Rural Agriculture" has formed. 展开更多
关键词 Urban and rural areas RELATION differENCE HISTORY China
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Spatiotemporal Evolution and Influencing Factors of Urban-rural Construction Land in Rural Industrialized Areas in China:Case Studies in Changyuan City and Xinxiang County of Henan Province
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作者 SHI Yanwen LI Xiaojian +1 位作者 HU Xueyao LI Zeyi 《Chinese Geographical Science》 SCIE CSCD 2023年第5期850-864,共15页
Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural ind... Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural industrialized areas in central China(Xinxiang County and Changyuan City of Henan Province).We used the average nearest neighbor index,spatial statistical analysis,and a structural equation model to analyze the spatiotemporal evolution and influencing factors of urban-rural construction land based on multisource spatial data and survey data.The results showed that:1)from 1975 to 2019,the spatial distribution of urban-rural construction land in rural industrialized areas had evolved from homogeneous distribution to local agglomeration.In terms of comparative analysis of cases,the spatial distribution of urban-rural construction land in Changyuan City had shown a trend from diffusion to agglomeration,and Xinxiang County had overall shown a spatial change from homogenization to agglomeration and then to regional integration development.2)The hot spots with increased urban-rural construction land significantly expanded,and they had a high degree of spatial overlap with industrial development.Among them,Xinxiang County was concentrated in central and marginal areas,and Changyuan was mainly concentrated in central urban areas.3)From the evolution of spatial proximity of urban-rural construction land,rural industrialized areas generally decline,showing the characteristics of internal differentiation in the rate of change.4)Industrial development,social economy,the policy environment,and urban development played a positive role in promoting the expansion of urban-rural construction land in rural industrialized areas.To promote the optimal use of regional land and the integrated development of urban-rural areas,we should combine the advantages of regional endowment,formulate development strategies according to local conditions,and adjust the way that land is used in a timely manner. 展开更多
关键词 urban-rural construction land rural industrialized areas spatiotemporal evolution influencing factors rural industrialization Henan Province China
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Overall Planning of Development of Urban-Rural Areas:A Policy Mechanism for Urban-Rural Coordinated Growth
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作者 Sun JinSociology Department, China Agricultural University, Beijing 100874, China 《Chinese Journal of Population,Resources and Environment》 2004年第1期57-60,共4页
While analyzing overall planning and coordinated development of urban-rural areas, this paper shows that overall planning for the development of urban-rural areas is a requirement for the best use of productive forces... While analyzing overall planning and coordinated development of urban-rural areas, this paper shows that overall planning for the development of urban-rural areas is a requirement for the best use of productive forces. It means the setting up of a policy mechanism for coordinated growth. Recognizing this, the government should set up a way to lead and manage a unified program to increase service and decrease controlling administration power, while safeguarding and fulfilling the farmers' ownership to the means of production. 展开更多
关键词 Overall planning of development of urban-rural areas Cxjordinated development of urban-rural areas
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Measurement of Grain Production Efficiency in Main Grain-producing Areas and Analysis of Inter-provincial Differences--A Study Based on Super-SBM Model and Malmquist Index
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作者 Qi Heng Su Jing-yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2022年第2期86-96,共11页
China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-p... China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-producing areas has become the fundamental way to strengthen the grain production capacity and improve the national food security capability,and to improve the efficiency of grain production in major grain-producing areas requires empirical support.This paper used the Super SBM model and the Malmquist index to measure the grain production efficiency of the main grain-producing areas from 2001 to 2020 from both static and dynamic perspectives,and compared the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas.The results showed that from 2001 to 2020,the grain production in the main grain-producing areas was in a relatively ineffective state,and the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas were obvious.The order of grain production efficiency in different soil types was black soil region>red-yellow soil region>paddy soil region>fluvo-aquic soil region,and the order of grain production efficiency of the provinces(autonomous regions)in the main grain-producing areas was Jilin>Heilongjiang>Inner Mongolia>Jiangxi>Hunan>Sichuan>Hubei>Jiangsu>Liaoning>Henan>Anhui>Shandong>Hebei.From 2001 to 2020,the total factor productivity of grain in the main grain-producing areas increased,but due to the trade-off between the technological progress and the growth of technical efficiency,the increase in the total factor productivity of grain in the main grain-producing areas was small,and the growth mainly came from the increase of input factors in this period.The total factor productivity of grain in Hebei,Heilongjiang,Liaoning,Jilin,Inner Mongolia,Shandong,Jiangsu,Henan and Anhui increased,but the increase was small,while the total factor productivity of grain in Jiangxi,Sichuan,Hunan and Hubei provinces declined. 展开更多
关键词 main grain-producing area grain production efficiency inter-provincial difference
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Walnut Tree Grafting Experiments in Different Areas in Yunnan Province 被引量:1
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作者 赵廷松 范志远 +8 位作者 谭凤琼 王洪艳 潘莉 邹伟烈 杜春花 刘娇 曾清贤 饶绍松 王斌 《Agricultural Science & Technology》 CAS 2017年第4期704-706,共3页
Yunnan has an area of 2.88 million hm2 walnut trees. Due to freezing in- jury and rapid growth, however, there are a lot of iron walnuts or inferior-quality walnuts ready for grafting. In five years, we conducted expe... Yunnan has an area of 2.88 million hm2 walnut trees. Due to freezing in- jury and rapid growth, however, there are a lot of iron walnuts or inferior-quality walnuts ready for grafting. In five years, we conducted experiments in Kunming (Yunnan Academy of Forestry), Gongshan County, Gucheng City, Luliang County, and Ludian County by cleft grafting, veneer grafting, bark grafting and whip grafting. The grafting approaches should be selected according to grafting requirements, characteristics, and survival rate. For example, with a low survival rate, cleft grafting can be abandoned, and the rest approaches might be chosen as per practical demands. 展开更多
关键词 YUNNAN different areas Walnut trees Grafting experiment
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Mapping and measuring urban-rural inequalities in accessibility to social infrastructures 被引量:1
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作者 Chenmeng Guo Weiqi Zhou +1 位作者 Chuanbao Jing Dawa Zhaxi 《Geography and Sustainability》 CSCD 2024年第1期41-51,共11页
Equal access to social infrastructures is a fundamental prerequisite for sustainable development,but has long been a great challenge worldwide.Previous studies have primarily focused on the accessibility to social inf... Equal access to social infrastructures is a fundamental prerequisite for sustainable development,but has long been a great challenge worldwide.Previous studies have primarily focused on the accessibility to social infras-tructures in urban areas across various scales,with less attention to rural areas,where inequality can be more severe.Particularly,few have investigated the disparities of accessibility to social infrastructures between urban and rural areas.Here,using the Changsha-Zhuzhou-Xiangtan urban agglomeration,China,as an example,we investigated the inequality of accessibility in both urban and rural areas,and further compared the urban-rural difference.Accessibility was measured by travel time of residents to infrastructures.We selected four types of social infrastructures including supermarkets,bus stops,primary schools,and health care,which were funda-mentally important to both urban and rural residents.We found large disparities in accessibility between urban and rural areas,ranging from 20 min to 2 h.Rural residents had to spend one to two more hours to bus stops than urban residents,and 20 min more to the other three types of infrastructures.Furthermore,accessibility to multiple infrastructures showed greater urban-rural differences.Rural residents in more than half of the towns had no access to any infrastructure within 15 min,while more than 60%of the urban residents could access to all infrastructures within 15 min.Our results revealed quantitative accessibility gap between urban and rural areas and underscored the necessity of social infrastructures planning to address such disparities. 展开更多
关键词 ACCESSIBILITY Social infrastructures urban-rural difference INEQUALITY Regional sustainability
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Inter-provincial Differences in Rice Multi-cropping Changes in Main Double-cropping Rice Area in China: Evidence from Provinces and Households 被引量:3
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作者 WANG Renjing LI Xiubin +4 位作者 TAN Minghong XIN Liangjie WANG Xue WANG Yahui JIANG Min 《Chinese Geographical Science》 SCIE CSCD 2019年第1期127-138,共12页
Since the early 1980 s, the multi-cropping index for rice has decreased significantly in main double-cropping rice area in China, which is the primary double-cropping rice(DCR) production area. This decline may bring ... Since the early 1980 s, the multi-cropping index for rice has decreased significantly in main double-cropping rice area in China, which is the primary double-cropping rice(DCR) production area. This decline may bring challenges to food security in China because rice is the staple food for more than 60% of the Chinese population. It has been generally recognized that rapidly rising labor costs due to economic growth and urbanization in China is the key driving force of the ‘double-to-single' rice cropping system adaption. However, not all provinces have shown a dramatic decline in DCR area, and labor costs alone cannot explain this difference. To elucidate the reasons for these inter-provincial distinctions and the dynamics of rice cropping system adaption, we evaluated the influencing factors using provincial panel data from 1980 to 2015. We also used household survey data for empirical analysis to explore the mechanisms driving differences in rice multi-cropping changes. Our results indicated that the eight provinces in the study can be divided into three spatial groups based on the extent of DCR area decline, the rapidly-declining marginal, core, and stable zones. Increasing labor cost due to rapid urbanization was the key driving force of rice cropping system adaption, but the land use dynamic vary hugely among different provinces. These differences between zones were due to the interaction between labor price and accumulated temperature conditions. Therefore, increasing labor costs had the greatest impact in Zhejiang, Anhui, and Hubei, where the accumulated temperature is relatively low and rice multi-cropping index declined dramaticly. However, labor costs had little impact in Guangdong and Guangxi. Differences in accumulated temperature conditions resulted in spatially different labor demands and pressure on households during the busy season. As a result, there have been different profits and rice multi-cropping changes between provinces and zones. Because of these spatial differences, regionally appropriate policies that provide appropriate subsidies for early rice in rapidly-declining marginal zone such as Zhejiang and Hubei should be implemented. In addition, agricultural mechanization and the number of agricultural workers have facilitated double-cropping; therefore, small machinery and agricultural infrastructure construction should be further supported. 展开更多
关键词 multi-cropping change INTER-PROVINCIAL differences cropping system adaption accumulated temperature double-cropping RICE area China
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Spatial-temporal Pattern and Differences of Land Use Changes in the Three Gorges Reservoir Area of China during 1975-2005 被引量:9
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作者 CAO Yingui ZHOU Weit +1 位作者 WANG Jing YUAN Chun 《Journal of Mountain Science》 SCIE CSCD 2011年第4期551-563,共13页
Regional land use changes are an important part of global changes.The research on land use changes in the Three Gorges Reservoir Area of China attracts a lot of attention owing to the Three Gorges Dam building.The Thr... Regional land use changes are an important part of global changes.The research on land use changes in the Three Gorges Reservoir Area of China attracts a lot of attention owing to the Three Gorges Dam building.The Three Gorges Reservoir Area becomes one of the important research areas.This study analyzed the transforming processes and traits of each land use type and the regional differences of land use changes during the past 30 years,summarized the distribution of different land use types in different buffer zones and regresses the equation areas and different buffer distances based on buffer analyses and regression analyses,and then analyzed the transforming rules in different buffer distances,got the optimal influence distances.The research results indicate that,(1) cultivated land lies at the northwest of the reservoir and was decreasing,however,the construction land was increasing,especially the urban construction land,a large number of land was flooded because of the reservoir water level rise;(2) urban area was sprawling quickly in developed and neighboring areas,and a great deal of cultivated land and a considerable amount of grassland were occupied;in the earlier time,rural settlements occupied lots of cultivated land and a sum of forestry land in the later time;(3) the optimum influenced distances for cultivated land and forestry land were 10-35 km,and for urban and rural settlements were in 5-20 km.Overall,this research can reflect the spatial-temporal characteristics of land use changes during the 30 years,and it is helpful for urban planning and land use planning in the reservoir area. 展开更多
关键词 Land use Spatial-temporal changes differences Three Gorges Reservoir area
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Soil quality and sustainable land use in urban-rural marginal area: a case study of Kaifeng 被引量:2
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作者 QIN Ming-zhou, ZHAO Jie (College of Environment and Planning, Henan University, Kaifeng 475001, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期356-365,共10页
By using the basic theories of physical geography, land resources and ecology, this article analyzes the soil quality of the rural-urban marginal area in Kaifeng. Computer techniques, based on soil samples analysis, a... By using the basic theories of physical geography, land resources and ecology, this article analyzes the soil quality of the rural-urban marginal area in Kaifeng. Computer techniques, based on soil samples analysis, are used to study soil quality changes in the Kaifeng’s rural-urban marginal area. While focusing on nutrient circle key links of input and output in soil, relying on numerous practical survey data, this article reveals clearly the impact of land use change on soil quality. 展开更多
关键词 urban-rural marginal area land use change soil quality soil nutriment balance
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GC-MS Analysis of Volatile Oils in Mango Leaves from Different Producing Areas 被引量:1
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作者 Xu FENG Chuanxian QIN +2 位作者 Qingxia HUANG Chengzhi DU Chenyan LIANG 《Medicinal Plant》 CAS 2021年第3期27-29,35,共4页
[Objectives]To analyze the composition of volatile oils from mango leaves from different producing areas.[Methods]The volatile oils in mango leaves from different areas was extracted by steam distillation,and the GC-M... [Objectives]To analyze the composition of volatile oils from mango leaves from different producing areas.[Methods]The volatile oils in mango leaves from different areas was extracted by steam distillation,and the GC-MS method combined with retention index and peak area normalization method was used for qualitative and quantitative analysis.[Results]The volatile oils of mango leaves in southern provinces contained high content of terpenes,such asα-gurjunene(18.39%-34.13%),(+)-viridiflorene(8.95%-16.30%)and(E)-β-ocimene(3.49%-7.63%).The volatile oils components of mango leaves were significantly different in different provinces,for example,mango leaves produced in Hainan Province contained a large amount ofβ-selinene(23.00%),but not in other provinces.[Conclusions]The origin had a great influence on the composition and contents of volatile oils in mango leaves. 展开更多
关键词 Mango leaves Volatile oils Gas chromatography-mass spectrometry different producing areas
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Coupling characteristics of stress and strain at different layers of different sub-regions in Yunnan and its adjacent areas
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作者 马宏生 张国民 +4 位作者 刘杰 江在森 华卫 王辉 王新岭 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第2期133-146,共14页
In this paper, we collect 6 361 waveform data to calculate the shear wave splitting parameters from a regional seismic network of 22 digital stations in Yunnan and its adjacent area from July 1999 to June 2005. By usi... In this paper, we collect 6 361 waveform data to calculate the shear wave splitting parameters from a regional seismic network of 22 digital stations in Yunnan and its adjacent area from July 1999 to June 2005. By using the cross-correlation method, 64 splitting events of 16 stations are processed. We also collect the splitting results of eight earthquake sequences to present the characteristics of shear wave splitting in Yunnan and its adjacent areas. The orientations of maximum principal compressive stress of three sub-regions in this area are derived from the CMT focal mechanism solutions of 43 moderate-strong earthquakes provided by Harvard University by the P axis azimuth-averaging method. The principal strain rate at each observatory is deduced from the observations of Crustal Movement Observation Network of China during the period from 1999 to 2004. In addition, the data of Pn aniso- tropy and SKS splitting of Yunnan and its adjacent areas are also collected. We have discovered from this study that the continental lithosphere, as a main seismogenic environment for strong earthquake, can be divided into blocks laterally; the mechanical behavior of lithosphere varies with depth and can be divided into different layers in the vertical orientation; the information of crustal deformation obtained from GPS might be affected by the type of blocks, since there are different types of active blocks in Yunnan and its adjacent areas; the shear wave splitting in this region might be affected mainly by the upper crust or even the surface tectonics. 展开更多
关键词 Yunnan and its adjacent areas shear wave splitting continental lithosphere stress and strain coupling of different layers
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Technical Study on Extraction of Procyanidins in Lycium ruthenicum Murr. Using Sub-critical Fluid 1,1,1,2-Tetrafluoroethane( R134a)and Content Determination from Different Producing Areas
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作者 Liang TAN Li ZHU Zhihao FENG 《Medicinal Plant》 CAS 2018年第5期36-40,44,共6页
[Objectives] To study the optimal conditions for extracting procyanidins fromLycium ruthenicum Murr. with sub-critical fluid R134 a( 1,1,1,2-tetrafluoroethane) in 1 L extraction kettle. [Methods]Taking the extraction ... [Objectives] To study the optimal conditions for extracting procyanidins fromLycium ruthenicum Murr. with sub-critical fluid R134 a( 1,1,1,2-tetrafluoroethane) in 1 L extraction kettle. [Methods]Taking the extraction rate of procyanidins as an indicator,the influence of pressure,temperature,and extraction time on extraction rate of procyanidins fromL. Ruthenicum Murr. was studied by single factor experimental methods and orthogonal array design. [Results]The order of factors affecting extraction rate of procyanidins was extraction temperature > extraction pressure > extraction time. The optimum extraction conditions were as follows: the extraction rate of procyanidins fromL. ruthenicum Murr. was the highest with extraction pressure of 1. 2 MPa,extraction temperature of 50℃ and extraction time of 90 min. The content of procyanidins in L. ruthenicum Murr. from different producing areas was determined by vanillin-HCl method under the optimal conditions. [Conclusions] The method has the advantages of easy operation,good selectivity,low extraction temperature and high extraction efficiency,which is suitable for extraction of procyanidins in L. ruthenicum Murr. 展开更多
关键词 Lycium ruthenicum Murr. PROCYANIDINS Sub-critical FLUID EXTRACTION technology R134A Vanillin-HCl method differENT producing areas Content determination
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An investigation of the health value and self-care capabilities of the elderly in urban-rural fringe area nursing homes and the related in?uencing factors
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作者 Ju-Ying Luo Ling-Lin Kong +4 位作者 Zhi-Xia Zhang Yan-Sheng Ye Cui-Yu Bao Li-Juan Tu Ya-Zhen Yang 《Chinese Nursing Research》 CAS 2016年第3期125-128,共4页
Objective:To investigate the health value and self-care capabilities of the elderly living in urban-rural fringe area nursing homes and the factors that influence these variables.Methods:A cluster sampling method wa... Objective:To investigate the health value and self-care capabilities of the elderly living in urban-rural fringe area nursing homes and the factors that influence these variables.Methods:A cluster sampling method was used to select 280 elderly individuals from seven urban-rural fringe communities in Xianning to complete a survey regarding their health value and self-care capabilities.Results:The total health value and self-care capability scores of the elderly were 7.45 ± 1.45 and100.25±22.56,respectively.Both of these scores significantly differed by age,education level,marital status,and income(P 〈 0.05,P 〈 0.01).Self-care capability was correlated with health value(r=0.521).A multivariate linear regression analysis showed that health value,marital status,and age predicted selfcare capability.Conclusions:Elderly people living in the urban-rural fringe area with higher health values also had higher self-care capabilities.The self-care capabilities of the elderly can be enhanced by improving their health value using the "knowing-trusting-acting" model. 展开更多
关键词 urban-rural fringe area ELDERLY Health value Self-care capability
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Study on Vegetation Characteristics & Soil Properties of Secondary Grassland in Farmland Areas Abandoned for Different Years in Minqin Oasis
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作者 Chunxiu GUO Lide WANG +5 位作者 Fanglan HE Dacheng SONG Hao WU Heran ZHAO Fanglin WANG Baoyi XU 《Agricultural Biotechnology》 CAS 2022年第5期65-71,共7页
[Objectives]This study was conducted to investigate the vegetation community characteristics and soil properties of secondary grassland in abandoned farmland areas of different years in Minqin Oasis. [Methods] By the ... [Objectives]This study was conducted to investigate the vegetation community characteristics and soil properties of secondary grassland in abandoned farmland areas of different years in Minqin Oasis. [Methods] By the method of space-for-time substitution, the changes of vegetation community characteristics(species composition, structural characteristics and important values) and soil microbial and enzyme activity were determined, and the correlation between various soil factors was analyzed. [Results](1) There were 39 species belonging to 32 genera of 15 families in the research area, including 8 shrub plants, 15 perennial herbs and 16 annual herbs.(2) Soil microbial biomass carbon, nitrogen and phosphorus contents were higher in the upper layer than in the lower layer, and the phenomenon of “surface aggregation” was obvious. The differences were different with the change of abandoned years.(3) Soil catalase content was the highest among different plots, and soil phosphatase, sucrase and urease all showed a trend of fluctuating decline with the increase in abandoned years. Soil enzyme changes were different in different soil layers. [Conclusions] This study can provide a theoretical basis for the restoration, reconstruction and rational protection and utilization of secondary grassland in abandoned farmland. 展开更多
关键词 Minqin Oasis different years Secondary grassland Abandoned area Vegetation characteristics Soil properties
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Content Determination of Total Flavonoids in Tetracera asiatica from 10 Different Production Areas in Guangxi
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作者 Fangfang DA Zhonghua DAI Hua ZHU 《Medicinal Plant》 2017年第5期11-13,共3页
[Objectives] To determine the content of total flavonoids in Tetracera asiatica from different production areas in Guangxi and provide a basis for improving the quality standards of crude drug. [Methods] Using 50% eth... [Objectives] To determine the content of total flavonoids in Tetracera asiatica from different production areas in Guangxi and provide a basis for improving the quality standards of crude drug. [Methods] Using 50% ethanol as extractor,NaNO_2-Al(NO_3)_3-NaOH as chromogenic system and rutin as the reference substance,the content of total flavonoids from the crude drug was determined. [Results] A method for determining the content of total flavonoids was established,the content of total flavonoids was 11.35-21.35 mg·g^(-1),and the average content was 17.64 mg·g^(-1). [Conclusions] The method had high repeatability and stability,and the method was simple,rapid and sensitive and suitable for quantitative analysis. 展开更多
关键词 Tetracera asiatica TOTAL FLAVONOIDS CONTENT determination GUANGXI differENT PRODUCTION areas
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Assessment of Human Impacts on Vegetation in Built-up Areas in China Based on AVHRR,MODIS and DMSP_OLS Nighttime Light Data,1992–2010 被引量:5
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作者 LIU Qinping YANG Yongchun +2 位作者 TIAN Hongzhen ZHANG Bo GU Lei 《Chinese Geographical Science》 SCIE CSCD 2014年第2期231-244,共14页
Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment espec... Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas.In this study,ArcGIS 10,ENVI 4.5,and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656Chinese cities from 1992 to 2010.Firstly,an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System(DMSP_OLS)nighttime light data.This improved algorithm has the advantages of high accuracy and speed.Secondly,a mathematical model(Human impacts(HI))was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer(AVHRR)Normalized Difference Vegetation Index(NDVI)and Moderate Resolution Imaging Spectroradiometer(MODIS)NDVI.HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects.The results were analyzed from four aspects:the size of cities(metropolises,large cities,medium-sized cities,and small cities),large regions(the eastern,central,western,and northeastern China),administrative divisions of China(provinces,autonomous regions,and municipalities)and vegetation zones(humid and semi-humid forest zone,semi-arid steppe zone,and arid desert zone).Finally,we discussed how human factors impacted on vegetation changes in the built-up areas.We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas.The negative human impacts followed an inverted′U′shape,first rising and then falling with increase of urban scales.China′s national policies,social and economic development affected vegetation changes in the built-up areas.The findings can provide a scientific basis for municipal planning departments,a decision-making reference for government,and scientific guidance for sustainable development in China. 展开更多
关键词 vegetation change human impact urbanization built-up areas nighttime light data Normalized difference Vegetation Index(NDVI)
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ANALYSIS ON POVERTY IN MOUNTAIN AREAS BASED ON OFF-FARM INDUSTRIES 被引量:4
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作者 WANG Qing, LI Hui-xia, CHEN Guo-jie, CHEN Yong(Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041,P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2003年第4期359-363,共5页
This paper reveals that agricultural growth trend in China is strongly correlated with the growth of off-farm industries-the curve of net income from off-farm industries reflects the general characteristics of net inc... This paper reveals that agricultural growth trend in China is strongly correlated with the growth of off-farm industries-the curve of net income from off-farm industries reflects the general characteristics of net income of households. That means the increase of net income of farm households is chiefly from off-farm industries,more than from agriculture. The authors therefore conclude that the "poverty" in mountain areas or the gap between mountain areas and plain areas lies in the underdevelopment of off-farm industries in mountain areas. Finally,the authors make suggestions of strategic adjustment of economic structure: 1) present situation of mountain areas in China should be fully considered; 2) a full industrial system is not our desire; 3) advantageous industries should be promoted to create famous products; 4) industrialization and urbanization in mountain areas should be promoted and so on. 展开更多
关键词 regional developmental difference off-farm industry per capita net income mountain areas of China
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Soil and Vegetation Spectral Coupling Difference (SVSCD) for Minerals Extraction from Hyperion Data in Vegetation Covered Area 被引量:3
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作者 CHEN Shengbo HUANG Shuang +1 位作者 LIU Yanli ZHOU Chao 《Chinese Geographical Science》 SCIE CSCD 2018年第6期957-972,共16页
Remote sensing data have been widely applied to extract minerals in geologic exploration, however, in areas covered by vegetation, extracted mineral information has mostly been small targets bearing little information... Remote sensing data have been widely applied to extract minerals in geologic exploration, however, in areas covered by vegetation, extracted mineral information has mostly been small targets bearing little information. In this paper, we present a new method for mineral extraction aimed at solving the difficulty of mineral identification in vegetation covered areas. The method selected six sets of spectral difference coupling between soil and plant(SVSCD). These sets have the same vegetation spectra reflectance and a maximum different reflectance of soil and mineral spectra from Hyperion image based on spectral reflectance characteristics of measured spectra. The central wavelengths of the six, selected band pairs were 2314 and 701 nm, 1699 and 721 nm, 1336 and 742 nm, 2203 and 681 nm, 2183 and 671 nm, and 2072 and 548 nm. Each data set's reflectance was used to calculate the difference value. After band difference calculation, vegetation information was suppressed and mineral abnormal information was enhanced compared to the scatter plot of original band. Six spectral difference couplings, after vegetation inhibition, were arranged in a new data set that requires two components that have the largest eigenvalue difference from principal component analysis(PCA). The spatial geometric structure features of PC1 and PC2 was used to identify altered minerals by spectral feature fitting(SFF). The collecting rocks from the 10 points that were selected in the concentration of mineral extraction were analyzed under a high-resolution microscope to identify metal minerals and nonmetallic minerals. Results indicated that the extracted minerals were well matched with the verified samples, especially with the sample 2, 4, 5 and 8. It demonstrated that the method can effectively detect altered minerals in vegetation covered area in Hyperion image. 展开更多
关键词 spectral difference coupling vegetation covered area Hyperion image mineral extraction
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