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The characteristic differences of tropical cyclones forming over the western North Pacific and the South China Sea 被引量:17
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作者 YUAN Jinnan WANG Dongxiao +2 位作者 LIU Chunxia HUANG Jian HUANG Huijun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第4期29-43,共15页
The best track dataset of tropical cyclones in the western North Pacific (WNP) and the South China Sea (SCS) from 1977 to 2005 during the satellite era, the NCEP/NCAR reanalysis dataset and the extended reconstruc... The best track dataset of tropical cyclones in the western North Pacific (WNP) and the South China Sea (SCS) from 1977 to 2005 during the satellite era, the NCEP/NCAR reanalysis dataset and the extended reconstructed sea surface temperature dataset are employed in this study. The main climatological characteristics of tropical cyclone formation over the WNP and the SCS are compared. It is found that there is obviously different for the locations of tropical cyclone origins, achieving the lowest central pressure and termination points between over the WNP and over the SCS. The annual number of tropical cyclones forming over the SCS is obviously less than over the WNP, and there is a significant negative correlation with the correlation coefficient being - 0.36 at the 5% significance level between over the WNP and over the SCS. The mean speed of tropical cyclone moving is 6.5 m/s over the WNP and 4.6 m/s over the SCS. The mean lowest central pressure of tropical cyclones is obviously weaker over the SCS than over the WNP. The tropical cyclone days per year, mean total distance and total displacement of tropical cyclone traveled over the WNP are all obviously longer than those over the SCS. Tropical cyclone may intensify to Saffir - Simpson hurricane scale 5 over the WNP, but no tropical cyclone can intensify to Saffir - Simpson hurricane scale 3 over the SCS. The changing ranges of the radii (R15,R16) of the 15.4 m/s winds them and the 25.7 m/s winds over the WNP are obviously wider than those over the SCS, and the median values of the radii over the WNP are also larger than those over the SCS. For the same intensity of tropical cyclones, both radii have larger medians over the WNP than over the SCS. The correlations of annual mean tropical cyclone size parameters between over the WNP and over the SCS are not significant. At the same time, the asymmetric radii of tropical cyclones over the WNP are different from those over the SCS. 展开更多
关键词 characteristic differences tropical cyclone western north Pacific and south China Sea
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Comparative Assessment of the Proximate and Mineral Composition of <i>Cucumis sativus</i>L. and <i>Solanum aethiopicum</i>L. Fruit Samples Grown in South Eastern and North Central Regions of Nigeria Respectively
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作者 H. C. Okeke O. Okeke +2 位作者 K. O. Nwanya C. R. Offor C. C. Aniobi 《Natural Resources》 2021年第8期237-249,共13页
<span style="font-family:""><span style="font-family:Verdana;">Studies were carried out to comparatively assess the proximate and mineral composition of </span><i><s... <span style="font-family:""><span style="font-family:Verdana;">Studies were carried out to comparatively assess the proximate and mineral composition of </span><i><span style="font-family:Verdana;">Solanum aethiopicum </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">Cucumis</span></i> <i><span style="font-family:Verdana;">sativus</span></i><span style="font-family:Verdana;"> L. fruit samples grown in the South Eastern and North Central regions of Nigeria respectively, following standard analytical procedures and instrumentation. The mineral elements (Na, K, Zn and Ca) were determined using atomic absorption spectrophotometer after wet digestion of the samples while the proximate parameters</span><i> </i><span style="font-family:Verdana;">(ash content, moisture content, crude fibre content, crude protein content, crude fat content and carbohydrate content) were determined in accordance with standard analytical procedures. The mean range of the moisture, crude fibre, crude protein, crude fat, ash and carbohydrate contents in the </span><i><span style="font-family:Verdana;">S. aethiopicum </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit samples grown in the North Central and South Eastern regions of Nigeria were 72</span></span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;">49</span><span style="font-family:Verdana;"> -</span><span style="font-family:Verdana;"> 88</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;">23, 2.15</span><span style="font-family:""> </span><span style="font-family:Verdana;">- 3.67, 1.31</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">- 1.85, 0.43 - 0.76, 0.51 - 0.84 and 3.18% - 5.72% respectively. Additionally, the moisture, crude fibre, crude protein, crude fat, ash and carbohydrate contents in the </span><i><span style="font-family:Verdana;">Cucumis sativus </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit</span><i> </i><span style="font-family:Verdana;">samples grown in the South Eastern and North Central regions of Nigeria, had mean range of values of 93.60 - 98.76, 0.53 - 0.77, 2.14 - 2.84, 0.29 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 0.46, 0.90 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 1.14 and 3.88% </span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;"> 4.66% respectively. The range of mean values of Na, K, Zn and Ca in the </span><i><span style="font-family:Verdana;">S. aethiopicum </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit samples from the South Eastern and North Central regions of Nigeria were 0.36 - 0.57, 1.92 - 2.80, 0.84 - 1.01 and 0.43 - 0.61 μg/g respectively. Also, Na, K, Zn and Ca</span><i> </i><span style="font-family:Verdana;">had mean range of values of 1.36 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 4.08, 10.16 - 13.09, 0.45 - 0.66 and 5.85 - 9.3</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">μg/g respectively in the </span><i><span style="font-family:Verdana;">C. sativus </span></i><span style="font-family:Verdana;">L. fruit samples grown in the South Eastern and North Central regions in Nigeria. The levels of the determined proximate of parameters</span><i> </i><span style="font-family:Verdana;">and mineral elements in the studied fruit samples from the investigated regions of Nigeria were statistically significant. This therefore indicates that the geographical locations where these fruit samples grew could have significantly impacted on their nutrient content levels. The levels of the determined proximate</span><i> </i><span style="font-family:Verdana;">parameters from the selected regions of Nigeria show</span></span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> that consumption of the fruit samples (</span><i><span style="font-family:Verdana;">S aethiopicum </span></i><span style="font-family:Verdana;">L. and</span><i><span style="font-family:Verdana;"> C. sativus </span></i><span style="font-family:Verdana;">L.)</span><i> </i><span style="font-family:Verdana;">especially regularly, would help supply the essential nutrients and minerals required for a healthy living. 展开更多
关键词 Solanum aethiopicum L. Cucumis sativus L. Proximate Parameters Mineral Elements south Eastern Region and north Central Region
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Comparative Assessment of the Phytochemical and Selected Heavy Metal Levels in <i>Cucumis sativus</i>L. and <i>Solanum aethiopicum</i>L. Fruit Sample Grown in South Eastern and North Central Regions of Nigeria Respectively
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作者 C. C. Aniobi O. Okeke +2 位作者 E. Ezeh H. C. Okeke K. O. Nwanya 《Natural Resources》 2021年第8期223-236,共14页
<span style="font-family:""><span style="font-family:Verdana;">Studies were carried out to comparatively assess the phytochemical and heavy metal levels in </span><i>&l... <span style="font-family:""><span style="font-family:Verdana;">Studies were carried out to comparatively assess the phytochemical and heavy metal levels in </span><i><span style="font-family:Verdana;">Solanum aethiopicum </span></i><span style="font-family:Verdana;">L. and </span><i><span style="font-family:Verdana;">Cucumis sativus </span></i><span style="font-family:Verdana;">L. fruit samples grown in the South Eastern and North Central regions of Nigeria respectively using standard analytical procedures and instrumentation. The fruit samples were assayed for selected heavy metals (Pb, Cd and Cu) using atomic absorption spectrophotometer after wet digestion of the samples. The five detected phytochemicals (flavonoids, alkaloids, terpenoids, saponins and glycosides) were present at varying amounts in the investigated fruit samples from the South Eastern and North Central regions of Nigeria. The range of mean values of flavonoids, terpenoids, saponins and glycosides in the </span><i><span style="font-family:Verdana;">S. aethiopicum </span></i><span style="font-family:Verdana;">L. fruit samples from the two studied regions were 0.50 - 0.57, 0.53 - 1.26, 0.44 - 0.78, 1.12 - 1.93 and 0.40 - 0.50 mg/g respectively. The range of mean values of flavonoids, alkaloids, terpenoids, saponins and glycosides in the </span><i><span style="font-family:Verdana;">C. sativus </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit samples from the two studied regions of Nigeria were 1.27 - 1.69, 0.53 - 0.55, 0.96 - 1.51, 0.41 - 0.83 and 0.90 - 1.74 mg/g respectively. The range of mean vales of Pb, Cd, and Cu in the </span><i><span style="font-family:Verdana;">S. aethiopicum </span></i><span style="font-family:Verdana;">L. fruit samples from the two studied regions were 0.15 - 0.24, 0 - 0.01, 0.78 - 1.12 μg/g respectively. 0.31 - 0.40, 0.02 - 0.05 and 0.62 -</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">0.96 μg/g were the range of mean values of Pb, Cd and Cu</span><i> </i><span style="font-family:Verdana;">respectively in the </span><i><span style="font-family:Verdana;">C. sativus </span></i><span style="font-family:Verdana;">L.</span><i> </i><span style="font-family:Verdana;">fruit samples from the two studied regions of Nigeria. Of the three investigated heavy metals, only Cd was at toxic levels in the </span><i><span style="font-family:Verdana;">C. sativus </span></i><span style="font-family:Verdana;">L. fruit samples from the South Eastern and North Central regions of Nigeria. This is therefore a health concern to the fruit consumers that includes these fruits in their habitual daily fruit diets. Although the therapeutic and pharmaceutical benefits that </span></span><span style="font-family:Verdana;">would</span><span style="font-family:Verdana;"> be derived from consuming</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the investigated fruit samples ha</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> been shown in this study, there is therefore a possible risk of undue exposure to environmental pollutants such as heavy metal, especially through growing these fruits in polluted soils resulting from unwholesome anthropogenic practices. For fruit consumers to derive maximum health benefits from consuming these fruits, pollutants like heavy metals must be at non-toxic levels and this can only be achieved by ensuring that these fruits samples are grown and harvested in environments with less anthropogenic activities. 展开更多
关键词 Cucumis sativus L. Solanum aethiopicum L. Phytochemicals and Heavy Met-als north Central Region and south Eastern Region
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Differences of Landscape Architecture between Residential Communities in North and South China
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作者 QI Yan 《Journal of Landscape Research》 2017年第1期117-119,共3页
This paper reviewed basic definitions of residential community landscape,analyzed the differences between residential community landscapes in north and south China,and also the causes of landscape differences from the... This paper reviewed basic definitions of residential community landscape,analyzed the differences between residential community landscapes in north and south China,and also the causes of landscape differences from the perspectives of climate,soil,vegetation species,water resources,historical and cultural background. Moreover,landscape design strategies suitable for actual conditions of China were put forward in terms of overall style,plant configuration,waterscape design,and construction details. 展开更多
关键词 north and south China Residential community landscape Landscape difference Solution
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ON THE DIFFERENTIATION OF THE ECONOMIC DEVELOPMENT OF CHINA’S NORTH,CENTRAL & SOUTH COASTAL REGIONS
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作者 Wu Zhe geography, SHANXI NORMAL UNIVERSITY 《南开经济研究》 CSSCI 北大核心 1994年第S3期19-24,39,共7页
Ⅰ. An analysis of the development trend of the economy in the north,middle aud south coastal regions or China since China began to implementreform and open
关键词 S north CENTRAL south COASTAL regions ON the DIFFERENTIATION OF the ECONOMIC DEVELOPMENT OF CHINA GDP THAN
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North-south difference of water mass properties across the Lembeh Strait, North Sulawesi, Indonesia 被引量:2
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作者 WANG Weibo PAN Aijun +2 位作者 EDI Kusmanto MUH Hasanudin DENY Sutisna 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第12期1-8,共8页
Two field observations were conducted around the Lembeh Strait in September 2015 and 2016, respectively.Evidences indicate that seawater around the Lembeh Strait is consisted of North Pacific Tropical Water(NPTW),Nort... Two field observations were conducted around the Lembeh Strait in September 2015 and 2016, respectively.Evidences indicate that seawater around the Lembeh Strait is consisted of North Pacific Tropical Water(NPTW),North Pacific Intermediate Water(NPIW), North Pacific Tropical Intermediate Water(NPTIW) and Antarctic Intermediate Water(AAIW). Around the Lembeh Strait, there exist some north-south differences in terms of water mass properties. NPTIW is only found in the southern Lembeh Strait. Water mass with the salinity of 34.6 is only detected at 200–240 m between NPTW and NPTIW in the southern Lembeh Strait, and results from the process of mixing between the saltier water transported from the South Pacific Ocean and the lighter water from the North Pacific Ocean and Sulawesi Sea. According to the analysis on mixing layer depth, it is indicated that there exists an onshore surface current in the northern Lembeh Strait and the surface current in the Lembeh Strait is southward.These dramatic differences of water masses demonstrate that the less water exchange has been occurred between the north and south of Lembeh Strait. In 2015, the positive wind stress curl covering the northern Lembeh Strait induces the shoaling of thermocline and deepening of NPIW, which show that the north-south difference of airsea system is possible of inducing north-south differences of seawater properties. 展开更多
关键词 water mass Lembeh Strait north-south difference
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DEFINITING AND ITS GEOLOGIC MEANING OF SOUTH-NORTH TREND FAULTED STRUCTURE BELT IN QIANGTANG BASIN, NORTH PART OF TIBET 被引量:6
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作者 Liu Chiyang,Yang Xingke,Ren Zhangli,Wang Dingyi,Cheng Gang,Zheng Menlin 《地学前缘》 EI CAS CSCD 2000年第S1期223-224,共2页
There were more expounding to north—west (west) trend fault and north\|east trend fault within Qiangtang Basin, North Part of Tibet, in the past literature. With increasing of geophysical exploration data, nearly eas... There were more expounding to north—west (west) trend fault and north\|east trend fault within Qiangtang Basin, North Part of Tibet, in the past literature. With increasing of geophysical exploration data, nearly east\|west trend structure began to be taken note to. Since the year of 1995, by a synthetic study to geophysical and geological data, that south\|north trend faulted structures are well developed. These structures should be paid much more attention to, because they have important theoretical meaning and practical significance.1 Spreading of south\|north faulted structure belt According to different geological and geophysical data, the six larger scale nearly south\|north faulted structure belt could be distinguished within the scope of east longitude 84°~96° and near Qiangtang Basin. The actual location of the six belts are nearly located in the west of the six meridian of east longitude 85°,87°,89°,91°,93°,95° or located near these meridian. The six south\|north faulted structure belts spread in the same interval with near 2° longitude interval. The more clear and much more significance of south\|north trend faulted structure belts are the two S—N trend faulted structure belts of east longitude 87° and 89°. There are S—N trend faulted structure belts in the west of east longitude 83°,81°, or near the longitudes. The structure belts spreading features,manifestation,geological function and its importance, and inter texture and structure are not exactly so same. The structure belts all different degree caused different region of geological structure or gravity field and magnetic field. There is different scale near S—N trend faulted structure belt between the belts. 展开更多
关键词 Qinghai—Tibet plateau QIANGTANG Basin southnorth TREND STRUCTURE BELT transverse transform STRUCTURE strike\|slip adjustment division of east—west region oil & gas prospecting
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Analysis of Northern regional folk culture on the Paper-cutart
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作者 向东 齐德金 《海外英语》 2014年第11X期202-204,222,共4页
Northern regional folk culture and art is colorful, bright vibrant, showing a flourishing pomp, The paper-cut art is one of the essential of the Pearl.The following article is based on the premise of the relationship ... Northern regional folk culture and art is colorful, bright vibrant, showing a flourishing pomp, The paper-cut art is one of the essential of the Pearl.The following article is based on the premise of the relationship between the North and the surrounding area customs and cultural heritage of folk art paper-cut, carrys on the review and analysis, focuses on northern folk paper-cut of origin, schools,, characteristics and the differences between the North and South. 展开更多
关键词 the northERN FOLK PAPER-CUT ART northERN FACTION n
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Gravity anomaly before the Leshan M5.0 earthquake? 被引量:1
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作者 Wei Jin Liu Ziwei +3 位作者 Sun Shaoan Kang Kaixuan Shen Chongyang Li Hui 《Geodesy and Geodynamics》 2015年第2期101-105,共5页
The North-South Seismic Belt was analyzed using gravity observation data from 2011 to 2015, and the nontidal analysis results show that there was a nonlinear gravity change at both the Chengdu and Guza seismostations ... The North-South Seismic Belt was analyzed using gravity observation data from 2011 to 2015, and the nontidal analysis results show that there was a nonlinear gravity change at both the Chengdu and Guza seismostations one month before the Leshan M5.0 earthquake. 展开更多
关键词 Gravity gradient Continuous gravity observations Nonlinear gravity change Leshan M5.0 earthquake Mobile gravity observation network Accumulation gravity change Different gravity change north-south Seismic Belt
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我国南北差距的历史演变与趋势研判
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作者 刘学良 沈扬扬 +1 位作者 李实 崔兆辉 《华南师范大学学报(社会科学版)》 北大核心 2024年第3期16-29,205,共15页
近年来,我国南北差距快速扩大问题受到社会各界的高度关注。分析可得数据发现,2021—2022年南北差距扭转了过去快速扩大的势头,南北差距的绝对水平和相对占比都有所下降。从行业看,工业和房地产业的差距缩小是南北差距缩小的主要原因;... 近年来,我国南北差距快速扩大问题受到社会各界的高度关注。分析可得数据发现,2021—2022年南北差距扭转了过去快速扩大的势头,南北差距的绝对水平和相对占比都有所下降。从行业看,工业和房地产业的差距缩小是南北差距缩小的主要原因;从部门看,政府财政收入、企业利润的南北差距都有所缩小,但居民收入的差距并没有缩小。结合国内外整体经济形势、省份经济表现等,我国已充分认识到南北差距扩大问题并采取措施应对,加之新冠疫情、俄乌冲突、国际通货膨胀特别是能源价格上涨、房地产市场波动等多重因素叠加,使得2021年以来南北差距有所缩小。但影响因素是短期性的,南北差距的长期趋势仍有待观察。南北差距扩大是我国区域发展格局出现的重大问题,应对南北差距扩大问题需有新思路,要发挥地区比较优势,尊重产业和人口向优势区域集中的客观规律,为重点开发地区、生态脆弱地区、能源资源地区等制定差异化开发政策,为重点生态功能区、农产品主产区、困难地区提供有效转移支付。 展开更多
关键词 南北差距 东西差距 二维分解 区域政策
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中国南北地区差异的要素分解与政策启示
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作者 吴利学 《区域经济评论》 北大核心 2024年第5期92-99,共8页
21世纪以来,中国南北地区差异日益扩大,各增长要素作用差异明显。利用发展核算基础上的地区差异分解框架和1978—2022年中国省级地区数据,研究全要素生产率、物质资本、劳动投入对南北地区经济差异的影响,结果发现,南北地区总产出差异... 21世纪以来,中国南北地区差异日益扩大,各增长要素作用差异明显。利用发展核算基础上的地区差异分解框架和1978—2022年中国省级地区数据,研究全要素生产率、物质资本、劳动投入对南北地区经济差异的影响,结果发现,南北地区总产出差异总体上呈现出持续扩大的趋势,但劳均产出近十多年来变化不大,劳动力和资本流入成为南方地区总产出更快增长的重要因素;全要素生产率差异一直是影响南北差异的重要因素,在很大程度上将会主导未来的区域差异趋势;物质资本差异受区域政策影响比较突出,但政策效果需要多方面协调考虑。要素分解对于缩小中国南北差异的政策启示在于,各地区要因地制宜发展新质生产力,进一步扩大改革开放,加快国际国内统一大市场建设,从而形成优势互补、高质量发展的区域经济布局。 展开更多
关键词 南北地区差异 发展核算 要素贡献分解 全要素生产率
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南水北调中线水源区植被指数时空变化分析
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作者 白景锋 张海军 白云帆 《湖北农业科学》 2024年第2期205-210,共6页
通过单线性回归(SLOPE)和地理加权回归(GWR)法,用植被指数(NDVI)研究南水北调中线水源区的植被分布变化趋势及机制,为保障水量和水质提供理论支撑。结果表明,2000—2019年水源区NDVI和入库流量呈现同步增长,植被逐渐变好,2007年以前NDV... 通过单线性回归(SLOPE)和地理加权回归(GWR)法,用植被指数(NDVI)研究南水北调中线水源区的植被分布变化趋势及机制,为保障水量和水质提供理论支撑。结果表明,2000—2019年水源区NDVI和入库流量呈现同步增长,植被逐渐变好,2007年以前NDVI增长幅度大,2008—2011年处于波动阶段,2012年以后增长幅度减小;NDVI变化最明显的是研究区东北部、西部和丹江口库区周边,这些区域地势相对低平、人口集中,中山和高山区NDVI变化不大;高程、坡度、人口数和城镇化是影响水源区NDVI分布的主要因素,降水、气温和产业比重是次要因素;各因素影响的强度和方向在空间上有异质性,自然地理因素对NDVI影响的最显著范围为高程1090 m以下、年均降水量980 mm以上的区域,人文地理因素影响的显著范围区是人口密度大、城镇化率高的地区。 展开更多
关键词 南水北调中线水源区 NDVI 时空变化
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Characteristics of land surface thermal-hydrologic processes for different regions over North China during prevailing summer monsoon period 被引量:28
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作者 ZHANG Qiang ZENG Jian ZHANG LiYang 《Science China Earth Sciences》 SCIE EI CAS 2012年第11期1872-1880,共9页
The observation stations of Northern China are divided into three regions:the arid Northwest China,the Loess Plateau,and the cool Northeast China.The consistencies,differences,and associated mechanisms of land surface... The observation stations of Northern China are divided into three regions:the arid Northwest China,the Loess Plateau,and the cool Northeast China.The consistencies,differences,and associated mechanisms of land surface thermal-hydrologic processes among the three regions were studied based on the normalization of major variables of land surface thermal-hydrologic processes,using data collected during prevailing summer monsoon period(July and August,2008).It is shown that differences of surface thermal-hydrologic processes are remarkable among the three regions because of different impacts of summer monsoon.Especially their soil wet layers occur at different depths,and the average albedo and its diurnal variations are distinctly different.Surface net short-wave radiation in the Loess Plateau is close to that in the cool Northeast China,but its surface net long-wave radiation is close to that in the arid Northwest China.And the ratio of net radiation to global solar radiation in the cool Northeast China is higher than the other two regions,though its temperature is lower.There are obvious regional differences in the ratios of surface sensible and latent heat fluxes to net radiation for the three regions because of distinct contribution of sensible and latent heat fluxesto land surface energy balance.The three regions are markedly different in the ratio of water vapor flux to pan evaporation,but they are consistent in the ratio of water vapor flux to precipitation.These results not only indicate different influences of climate and environmental factors on land surface thermal-hydrologic processes in the three regions,but also show that summer monsoon is important in the formation and variation of the pattern of land surface thermal-hydrologic processes. 展开更多
关键词 different regions of north China prevailing summer monsoon period coordinated experiment land surface thermalhydrologic processes influence factors
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基于典型气象数据分析的南北方 供暖特性研究
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作者 丁勇 向一心 《暖通空调》 2024年第4期120-126,共7页
针对南、北方供暖的需求差异,基于历年气象数据,综合考虑累年最冷月平均温度、供暖度日数HDD18、供暖期天数等多种因素,分析了中国南、北方8个典型城市的气候特征;同时结合需求调研和温度分布、波动差异对比情况,讨论了不同地区热负荷... 针对南、北方供暖的需求差异,基于历年气象数据,综合考虑累年最冷月平均温度、供暖度日数HDD18、供暖期天数等多种因素,分析了中国南、北方8个典型城市的气候特征;同时结合需求调研和温度分布、波动差异对比情况,讨论了不同地区热负荷动态特性及负荷求解宜使用的方法;分析总结了南、北方地区的系统运行特征情况,给出了关于供暖系统设计、系统形式、运行策略的建议;并通过实际案例具体分析了供暖系统设置的适宜性问题,为后续供暖设计方法、参数确定,供暖方式选择和系统设置提供基础。 展开更多
关键词 供暖 南北方供暖差异 气象数据 供暖需求特性 系统特征 案例分析
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城市创新效率的南北差异及其空间演化特征研究
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作者 施晓丽 朱卫康 《新余学院学报》 2024年第4期14-26,共13页
选取2001—2021年作为研究时段,以全国287个地级市为基本研究单元,使用三阶段DEA模型测度出城市创新效率值。采用ArcGIS空间技术进行南北地区城市创新效率差异的时空格局演变特征分析,借助变异系数、Dagum基尼系数及其分解法测度南北地... 选取2001—2021年作为研究时段,以全国287个地级市为基本研究单元,使用三阶段DEA模型测度出城市创新效率值。采用ArcGIS空间技术进行南北地区城市创新效率差异的时空格局演变特征分析,借助变异系数、Dagum基尼系数及其分解法测度南北地区城市创新效率的差异来源情况等。结合ESDA空间分析技术、通过全局和局部空间自相关指数研究南北地区城市创新效率空间集聚特征,旨在为中国优化区域创新战略、构建创新型国家提供研究视角与改进思路。 展开更多
关键词 城市创新效率 南北差异 三阶段DEA 空间演化 ESDA
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南北主食差异对家庭食物浪费碳足迹的影响——来自CHNS的经验证据
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作者 钱龙 熊可馨 胡文华 《安徽农业大学学报(社会科学版)》 2024年第3期106-117,共12页
减少食物浪费是保障粮食安全、缓解全球气候变暖的重要举措。基于中国健康与营养调查(CHNS)和中国食品生命周期评估数据库(CFLCAD),从南北主食差异这一视角出发,基于生命周期理论分析中国居民家庭的食物浪费碳足迹。研究发现,中国居民... 减少食物浪费是保障粮食安全、缓解全球气候变暖的重要举措。基于中国健康与营养调查(CHNS)和中国食品生命周期评估数据库(CFLCAD),从南北主食差异这一视角出发,基于生命周期理论分析中国居民家庭的食物浪费碳足迹。研究发现,中国居民家庭人均日食物浪费碳足迹为62.255 g CO^(2)eq。相比以小麦为主食的北方家庭(人均食物浪费碳足迹为53.704 g CO^(2)eq/d),以大米为主食的南方家庭有着更高的人均食物浪费碳足迹(69.628 g CO^(2)eq/d)。此外,显著影响家庭食物浪费碳足迹的还有户主年龄、主要女性成员年龄、主要女性成员受教育年限、家庭人口规模与结构、收入水平、储藏条件和膳食知识、家庭类型等变量。 展开更多
关键词 食物浪费 南北主食差异 碳足迹 生命周期理论
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国际南北运输走廊发展进程与前景分析
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作者 蒲公英 冯博文 《印度洋经济体研究》 2024年第4期138-151,156,共15页
俄乌冲突爆发后,西方国家对俄制裁趋于常态化,欧亚运输网络中经俄罗斯进入欧洲的运输路线遭遇阻碍。在此背景下,联通波罗的海、里海、印度洋的南北向国际运输走廊地缘战略意义得到提升。以俄罗斯、伊朗、印度为代表的国家正将国际南北... 俄乌冲突爆发后,西方国家对俄制裁趋于常态化,欧亚运输网络中经俄罗斯进入欧洲的运输路线遭遇阻碍。在此背景下,联通波罗的海、里海、印度洋的南北向国际运输走廊地缘战略意义得到提升。以俄罗斯、伊朗、印度为代表的国家正将国际南北运输走廊建设重新提上议事日程,试图在新的动荡变革时期寻求新的战略通道突破,为贸易发展与能源领域合作创造机遇。当前,国际南北运输走廊沿线国家的主观建设需求显著提升,但沿线国家发展走廊的主观需求与客观建设能力及货运需求不匹配的核心问题短期内难以解决。长远来看,国际南北运输走廊以里海—中亚为轴心,拥有与传统欧亚运输线路对接的重要潜力,有望促进欧亚运输体系的多象限发展,深度激发欧亚大陆的国际物流大通道作用。国际南北运输走廊辐射面广,需要沿线及辐射地区国家齐心协力积极应对复杂局面,共同营造多方共赢的开放发展格局。为发挥更为巨大的联通效应,国际南北运输走廊的未来发展离不开与“一带一路”倡议的务实对接。 展开更多
关键词 国际南北运输走廊 俄罗斯 印度 里海国家 欧亚运输
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The burden of and risk factors for active trachoma in the North and South Wollo Zones of Amhara Region,Ethiopia:a crosssectional study
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作者 Beselam Tadesse Alemayehu Worku +1 位作者 Abera Kumie Solomon Abebe Yimer 《Infectious Diseases of Poverty》 SCIE 2017年第1期1270-1281,共12页
Background:Trachoma is a disease of the eye,caused by the bacteria Chlamydia trachomatis,which can lead to blindness if left untreated.Ethiopia is one of the most trachoma-affected countries in the world.The objective... Background:Trachoma is a disease of the eye,caused by the bacteria Chlamydia trachomatis,which can lead to blindness if left untreated.Ethiopia is one of the most trachoma-affected countries in the world.The objective of this study was to determine the prevalence of and associated risk factors for active trachoma among children in selected woredas of North and South Wollo Zones in Amhara Region,Ethiopia.Methods:This study was a community-based,cross-sectional study,which was conducted from October to December 2014 among children aged 1-8.A four-stage random cluster sampling technique was employed to select the study areas and participants.From each selected household,one child was clinically assessed for active trachoma.A structured questionnaire was used to collect sociodemographic,behavioral,and clinical data.Multivariate logistic regression analysis was used to analyze the association between predictor variables and active trachoma.Results:The overall prevalence of active trachoma among 1358 children was found to be 21.6%(95%CI:19.4-23.8%).When analyzed by the presence or absence of individual WHO simplified system signs of active trachoma,trachomatous inflammation-follicular cases constituted18%(95%CI:15.9-20.2%),while 4.7%(95%CI:3.6-5.8%)were trachomatous inflammation-intense cases.Ocular discharge(aOR=5.2;95%CI:3.3-8.2),nasal discharge(aOR=1.8;95%CI:1.2-2.7),time taken to fetch water(aOR=0.02;95%CI:0.01-0.05),frequency of hand and face washing(aOR=4.4;95%CI:1.1-17.8),and access to a latrine(aOR=0.006;95%CI:0.001-0.030)were found to be independently associated with the presence of active trachoma.Conclusions:There is a high burden of active trachoma among children in the study areas.Lack of personal hygiene and limited access to a safe water supply and latrines were associated with increased prevalence of active trachoma.In order to reduce the burden of active trachoma,facial cleanliness and environmental improvement components of the SAFE strategy should be upgraded in the study areas. 展开更多
关键词 north Wollo south Wollo Amhara region Ethiopia TRACHOMA Prevalence SAFE strategy WASH
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中医体质与骨质疏松症相关性的南北方地区差异Meta分析
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作者 吴晓睿 刘艳秋 +3 位作者 梅笑 王丹 侯逢源 刘瑞霞 《山东中医杂志》 2024年第5期488-496,538,共10页
目的:探索南北方地区骨质疏松症患者中医体质的分布特点。方法:筛选2009年4月至2023年8月发表的有关中医体质与骨质疏松相关性研究的文献,以“骨质疏松”“中医体质”“osteoporosis”“traditional Chinese medical constitution”等... 目的:探索南北方地区骨质疏松症患者中医体质的分布特点。方法:筛选2009年4月至2023年8月发表的有关中医体质与骨质疏松相关性研究的文献,以“骨质疏松”“中医体质”“osteoporosis”“traditional Chinese medical constitution”等为主题词进行检索,将最终纳入研究的文献按地区进行南北方划分,对纳入文献中的体质与骨质疏松数据进行南北方差异分析。结果:最终纳入研究的文献共19篇,其中南方地区9篇,北方地区10篇。Meta分析结果显示,南方地区气虚质(OR=2.46,95%CI:1.68~3.62)、阳虚质(OR=2.19,95%CI:1.83~2.63)发生骨质疏松的风险较高,痰湿质(OR=0.41,95%CI:0.32~0.53)及湿热质(OR=0.56,95%CI:0.35~0.89)为其保护性体质;北方地区血瘀质(OR=2.32,95%CI:1.51~3.58)、阳虚质(OR=2.28,95%CI:1.56~3.34)及阴虚质(OR=1.68,95%CI:1.07~2.64)发生骨质疏松的风险较高。结论:南北方地区体质与骨质疏松的相关性具有差异,在南方,气虚质、阳虚质为危险因素,痰湿质、湿热质为保护因素;在北方,血瘀质、阳虚质、阴虚质为危险因素。 展开更多
关键词 中医体质 骨质疏松症 地域差异 南方地区 北方地区 META分析
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蒙元时期边疆屯垦经济的发展、南北差异及环境成因
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作者 张彦虎 冯雪涛 《石河子大学学报(哲学社会科学版)》 2024年第1期101-110,共10页
屯垦经济是古代边疆经济的重要组成部分。尤其在蒙元时期,边疆屯垦经济的发展不仅成效巨大,而且南北边疆呈现出显著的发展差异和趋势特点。究其原因,运用气候变迁、生态平衡与非平衡等研究视角可以发现,中世纪暖期气候转向小冰期,以及... 屯垦经济是古代边疆经济的重要组成部分。尤其在蒙元时期,边疆屯垦经济的发展不仅成效巨大,而且南北边疆呈现出显著的发展差异和趋势特点。究其原因,运用气候变迁、生态平衡与非平衡等研究视角可以发现,中世纪暖期气候转向小冰期,以及由此引发的南北边疆生态环境不同变化和生态系统(平衡与非平衡性)对屯垦生产影响制约作用的改变,再加上由此带来的疫病影响等因素,是造成这一时期南北边疆屯垦经济差异发展的主要环境成因。 展开更多
关键词 蒙元时期 边疆屯垦经济 南北差异
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