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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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Characteristics of seismic reflections in central region of the South China Sea and their geological significance 被引量:1
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作者 刘建华 金翔龙 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第3期103-113,共11页
More than 4 000 km 48-channel seismic reflection data from the central region of the South China Sea have been interpreted. Five seismic interfaces have been distinguished, named T1, T2, T4, T6 and Tg respectively Mea... More than 4 000 km 48-channel seismic reflection data from the central region of the South China Sea have been interpreted. Five seismic interfaces have been distinguished, named T1, T2, T4, T6 and Tg respectively Meanwhile, five seismic sequences numbered I - V have been divided with the ages of Quaternary and Pliocene, Later Mocene, Earlier and Middle Miocene, Oligocene and Pre- Oligocene separately. Sequences I-II overlie all parts of the area. In the continental slope and island slope, Sequences III-V are mainly found in the grabens. Sequence III is found at moot profiles of the deep-sea basin, and Sequnce IV is seen not only at the margins of the east subbasin but also at the margins of the southwest subbasin. Strong reflection from Moho is found at most profiles of the deep-sea basin. The depth of Moho varies between 10 and 12 km, with a thickness of 6- 8 km for the crust. Calculated by age-basement depth correlation formula, the age of basaltic basement in the southwest subbasin is 51-39 Ma. It is indicated that the evolution of the southwest subbasin is simultaneous with or earlier than that of the east subbasin. 展开更多
关键词 central region of the south China Sea seismic reflection evolution of the back-arc basin
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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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Eurasia Continental Bridge——An Important Link of the Coordinated Development between China's Eastern,Central and Western Regions
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作者 Zhao Ming Li Zhukun 《China's Foreign Trade》 1996年第10期42-42,共1页
The new Eurasia Continental Bridgeruns from East China to Central andWest China, crossing 11 provincesand regions, namely Jiangsu, Shandong,Hubei, Anhui, Shaanxi, Gansu, Shanxi,Sichuan, Qinghai, Xinjiang and Ningxia.T... The new Eurasia Continental Bridgeruns from East China to Central andWest China, crossing 11 provincesand regions, namely Jiangsu, Shandong,Hubei, Anhui, Shaanxi, Gansu, Shanxi,Sichuan, Qinghai, Xinjiang and Ningxia.The total area is 3.6 million sq km and thepopulation is about 300 million, accountingfor a third and a quarter of the whole countryrespectively. The area is very rich in naturalresources, so it is called an "Economic goldbelt" and "Gold corridor". Aerial remote-control survey indicates that along thecontinental bridge from Lianyungang to theAla Mountains within China’s boundary, 展开更多
关键词 area In An Important Link of the Coordinated Development between China’s eastern central and Western regions Eurasia Continental Bridge
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Genesis and Quality of Groundwater in the Southeastern Region of Southern Vietnam
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作者 Chau Tran Vinh Tran Hong Thai +5 位作者 Doan Van Canh Dang Due Nhan Nguyen Cao Huan Nguyen Van Nghia Nguyen Hong Hieu Trinh Thi Thu Van 《Journal of Environmental Science and Engineering(A)》 2017年第6期277-292,共16页
关键词 地下水质量 东南部地区 成因 化学分析方法 地球化学参数 同位素组成 溶解无机碳 实验室测定
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Geospatial Technology Potentials in Reawakening the Consciousness of Soil Distribution in Nigeria’s North-Central Region and Mediating the Herdsmen-Farmers Conflicts
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作者 Ugonna C. Nkwunonwo Francis I. Okeke +1 位作者 Emmanuel N. Chiemelu Elijah S. Ebinne 《Journal of Geoscience and Environment Protection》 2019年第2期156-175,共20页
The pervasive herdsmen-farmers conflicts in the north-central region of Nigeria have changed the narrative of Nigeria’s enduring ethnic crises to ideologies, which are in-controvertibly sinister. The consequences of ... The pervasive herdsmen-farmers conflicts in the north-central region of Nigeria have changed the narrative of Nigeria’s enduring ethnic crises to ideologies, which are in-controvertibly sinister. The consequences of this tension, which has defied possible military responses, political, religious and cultural strategies are potentially devastating, not just for Nigeria, but the whole of West African region. Since the particular nature of these conflicts increasingly highlights the significance and inevitability of land resources for crops farming and cattle rearing, it is imperative to create awareness of the elemental nature of soils, especially their diversities in these conflict-prone areas. This study’s objective was to produce a Geographic Information System (GIS) based digital soil map (DSM) of the north-central region of Nigeria, and to delineate soil distribution and unique properties. Based on this study, the DSM offers a quick access to quantitative soil data covering the study area. It indicates that soil mapping units 15d, 18d and 24b are dominant, and constitute about 40% of the local arable lands. The broad pattern of distribution of these soils reflects both the climatic conditions and the geological structure of the region. The soils are highly weathered with limited capacities to supply essential nutrients needed by crop plants. These issues raise a number of questions, most of which focuses on the best possible way to maximize these soils to accommodate both crop farming and cattle rearing. It is our hope that taking the advantage of GIS to stimulate the knowledge and consciousness of soil distribution in the region will place the weight where it is appropriate in terms of food security through crops production and cattle rearing, and hence forge a more realistic pathway to reconciliation and conflict resolution. 展开更多
关键词 HERDSMEN SEDENTARY FARMERS north-central region of Nigeria GIS Digital Soil Map Food Security Conflict Resolution
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Roles and Functions of Tourism Destinations in Tourism Region of South Anhui:A Tourist Flow Network Perspective 被引量:9
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作者 LIU Fajian ZHANG Jinhe +3 位作者 ZHANG Jie CHEN Dongdong LIU Zehua LU Song 《Chinese Geographical Science》 SCIE CSCD 2012年第6期755-764,共10页
Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the persp... Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the perspective of relationship.This article conducted an empirical analysis for Tourism Region of South Anhui(TRSA) and revealed the necessity and feasibility of studying the roles and functions of destinations from tourist flow network's perspective.The automorphic equivalence analysis and centrality analysis were used to classify 16 destinations in TRSA into six role types:tourist flow distribution center,hub of tourist flows,passageway destination,common touring destination,attached touring destination,and nearly isolated destination.Some suggestions were given on suitable infrastructure construction and destinations service designs according to their functions in network.This destination role positioning was based on tourist flow network structure in integral and macroscopic way.It provided an important reference for the balanced and harmonious development of all the destinations of TRSA.In addition,this article verified the applicability of social network analysis on tourist flow research in local scale,and expanded this method to destination role and function positioning. 展开更多
关键词 网络功能 目的地 旅游区 职能 皖南 基础设施建设 空间结构 实证分析
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Petrology and geochemical characteristics of Precambrian granitic basement complex rocks in the southernmost part of North-Central Nigeria 被引量:2
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作者 Obiora S.C. Ukaegbu V.U. 《Chinese Journal Of Geochemistry》 EI CAS 2009年第4期377-385,共9页
The Precambrian basement complex in the southernmost part of North-Central Nigeria is underlain by migmatitic banded gneisses, granitic intrusions and dykes of dolerite, rhyolite porphyry and pegmatite. The rocks are ... The Precambrian basement complex in the southernmost part of North-Central Nigeria is underlain by migmatitic banded gneisses, granitic intrusions and dykes of dolerite, rhyolite porphyry and pegmatite. The rocks are generally felsic, containing modal and normative hypersthene, as well as normative corundum. The basement complex has experienced high-grade regional metamorphism as indicated by the presence of hypersthene and plagioclase of andesine composition. Anatectic melting is suggested by the occurrence of ptygmatic folds, folded gneissose foliation, numerous quartzo-feldspathic veins and lenses of dark-colured, micaceous schistose rocks. Geochemically, the rocks have magnesian, calc-alkalic and strongly peraluminous characteristics. Their overall characteristics suggest derivation from progressive (fractional) partial melting of pelitic rocks during high-grade regional metamorphism, possibly associated with intense hydrothermal activities. The magnesian characteristics reflect close affinity to relatively hydrous, oxidizing melts and source regions in settings broadly related to subduction. 展开更多
关键词 岩石地球化学特征 前寒武纪基底 尼日利亚 花岗岩 中央 区域变质作用 流纹斑岩 叶状结构
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Diagnostic Analysis on a Regional Rainstorm Weather in North-central Henan Province 被引量:1
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作者 SUN Zhong-yi ZHANG Zhen LI Ji-hua 《Meteorological and Environmental Research》 CAS 2011年第6期19-23,共5页
[Objective] The research aimed to analyze a regional rainstorm weather process in north-central Henan Province. [Method] Based on the conventional meteorological observation data and the rainfall data of Henan Meteoro... [Objective] The research aimed to analyze a regional rainstorm weather process in north-central Henan Province. [Method] Based on the conventional meteorological observation data and the rainfall data of Henan Meteorological Station, the diagnostic analysis of atmospheric thermodynamics and dynamics on a rainstorm weather process in north-central Henan Province on July 19, 2010 was carried out. The characteristics of physical quantity field and the evolution of weather situation in north-central Henan Province when the rainstorm happened were studied. [Result] Western Pacific subtropical high strengthened to extend westward. The dynamic uplifting of low vortex at the middle and low layers, the strong water vapor transportation of southwest low-level jet caused the regional rainstorm weather process in north-central Henan Province. The diagnostic results of physical quantity showed that the deep, thick wet layer and the sustained water vapor convergence provided the abundant water vapor for rainstorm generation. The positive vorticity advection center developed and spread from northwest to southeast, which was favorable for the development of vertical movement. The structure maintenance of positive vorticity at the middle and low layers, negative vorticity at the middle and high levels provided the power condition for the regional rainstorm generation. The pumping effect of convergence at the middle and low layers, divergence at the high layer was favorable for the strengthening of vertical ascending motion at the low layer. The uplifting effect of dew point front at the middle and low layers triggered the release of unstable energy. The confrontation of warm and cold air was one of the important reasons for the regional rainstorm. TBB characteristic analysis showed that TBB was from -60 to -50 ℃ in north-central Henan Province in the whole strong precipitation time, and the moving speed was equivalent to that of southwest vortex. The low-value belt of TBB corresponded with the rainstorm occurrence zone in Henan, and the minimum-value center of TBB was basically consistent with the strongest center of precipitation. [Conclusion] The research provided the scientific basis for the short-term forecast of rainstorm. 展开更多
关键词 north-central Henan Province regional rainstorm Weather process Diagnostic analysis China
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A stratigraphical-geochemical study on the Chaco Paraná continental rift basin—An approach study based on regional sedimentology and drill-hole core analyses, South América
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作者 Roberto Toga 《Chinese Journal Of Geochemistry》 EI CAS 2006年第3期195-215,共21页
This paper is focused on a geologic “regional rift basin system pattern” and its stratigraphical-geochemical relationship. This is mainly based on the littoral shallow marine sedimentary succession paleogeography an... This paper is focused on a geologic “regional rift basin system pattern” and its stratigraphical-geochemical relationship. This is mainly based on the littoral shallow marine sedimentary succession paleogeography and deposits. These successions characterize the large extensional intracratonic Chaco Paraná Basin rift system. The basin is located in South America west of the Brazilian Shield. The analyzed rift basin system evolved from the Upper Cretaceous (Late Campanian-Senonian-Maastrichtian-Early Paleocene) to Quaternary time. The siliciclastic littoral shallow marine successions were deposited from Early Senonian-Maastrichtian to Late Miocene during three main successive littoral shallow marine transgressions of continental extension.; These transgressions happened over the wide pediplanized terrains of South America. These lands exist west of the more positive areas, between the Brazilian Shield and the foreland massifs that were settled in the more westernwards areas. Later, these regional foreland massifs were coupled and raised to the Andean Orogen Belt during the last 5 million years.; The extensive intracratonic pediplanized low topographic relief areas were the reservoirs of siliciclastic littoral shallow marine succession deposits during the three successive widespread vast continental littoral shallow marine transgressions.; The first transgression began at the Latest Campanian-Senonian and/or Early Maastrichtian time. After this episode, the sedimentary depositional systems continued during the Cenozoic until the Latest Miocene. These successions constitute a major allostratigraphic unit. The limit with underlying units is the regional unconformity between the regional volcanic event (Jurassic-Cretacic and interleaved eolianite sandstones) at the base and the undifferentiated Quaternary sediments (called as the Pampeano and Post-Pampeano Formations sensu lato). Based on many facies analyses there had been checked out different levels in the eustatic sea level variations within the allostratigraphic unit.; Three major stages of extensional climax were recognized and related to the stages of conspicuous eustatical sea-level variations. They happened during the Latest Senonian-Paleocene, Eocene and Miocene.; The first transgression occurred during the Upper Cretaceous-Paleocene although the sedimentary deposits related to this event are scarce, which are only a few meters in thickness. However, the Upper Cretaceous-Paleocene succession is very well recognized in the actual pre-Andean zone in the north-west of Argentina and Bolivia (the Sierras Subandinas and the meridional imbricated fault systems just joint to the actual orogen, i.e., Quebrada de Humahuaca outcrops).; During the Eocene and Middle to Latest Miocene occurred the second and third extensive regional littoral shallow marine transgressions. They are present either in well log registers as in most widespread outcrops on the entire Southamerican continent.; The regional analysis led to the deduction of long periods of tectonic quiescence, at least three of them. They may be inferred and synchronously related with eustatic highstand sea level variations that occurred during the Late Paleocene-Early Eocene, Latest Eocene-Early to Mid Oligocene and Middle-to-Late Oligocene-Early Miocene.; The structural style is related with major extensional N-S strike faultings (regional tilted and faulting blocks). On the other hand, quite a number of strike-slip faults (mainly of regional characteristic) are present crossing the area. They have a clear influence on the accommodation and transfer zones of the rift basin system. The strike is north-west to south-east on the border of the basin, to the west, in the contact with the Pampean Ridges and the narrow-meridionally-extense Sub-Andean folded trend (mainly Paleozoic units belonging to the so-called Sierras Subandinas geological province). Also, at the western edge of thestudied area, there exist many large shear zones and upthrust faults. The strike-slip regional faults dislocated the Pampean and Sub-Andean blocks due to the interaction of crossing regional tilted and fault blocks. For this reason, an en echelon regional block model is characteristic. Incipient contaminated igneous activities were associated with this cortical weak zones.; Domes, needles and necks of volcanic and sub-volcanic origin appear as the landscape of the region. A part of the igneous activity was dated on Latest Pliocene although mainly corresponding to Pleistocene and Holocene. This deduction is obvious because their morphological constitution was never eroded. The volcanic aparatous are morphologically unmodified from their extrusion to present days.; All the studied successions seem to resemble a long persisting erosive, transportation and deposition episode. This phenomenon is linked to a large regional (continental) unconformity dated at Late Cretaceous. The entire analyzed sedimentary succession deposits and their siliciclastic facies associations correspond clearly to a “heterolithic facies succession” which is very common within persisting tide-dominated depositional systems (passive margins). In fact, this is what happened during Cenozoic times (Torra, 1998b, 2001a). The heterolithic Miocene facies deposits constitute one of the best continental exposed examples.; Paleogeographical evidence showed that the Paranense and Amazonic Sea transgressions had been a littoral shallow marine connection during long time from Middle to Late Miocene. During the Late Cretaceous and Eocene periods marine connections were also active in the region. This fact is strongly supported by the tectonic and geomorphological framework of the proto-Southamerican continent, fossil remains and similar sedimentary deposits.; The geochemical results showed an outstanding similarity among the three sandy-muddy successions herein studied. Both major and trace elements always show the same geochemical patterns. Specially mentioned are the elements gallium, cesium, chromium, barium, vanadium, thorium, zirconium, rubidium and strontium because they present very constant values through all successions.; The Paranense and Amazonic epicontinental seas had been connected to the Pacific Ocean during the three marine episodes. The connections were formed by narrow inter-mountain valleys, present in the pre-Andean foreland massifs. These events occurred prior to the main orogenesis elevation of the Andean orogen belt in the last 5 to 1 Ma (Pliocene-Latest Pleistocene).; This paper shows, for the first time, a synthetic stratigraphical-geochemical “regional model” for the Chaco Paraná Basin rift system which should be largely improved in later studies. The Chaco Paraná Basin carries many unexamined-unexplored natural resources which need more regional and local studies for their evaluation. This is in spite of the area that has the problem of a significative vegetation coberture and scarce good outcrops. The development of modern techniques of data acquisition will help to overcome these difficulties. 展开更多
关键词 地层学 地球化学 古地理学 裂谷盆地 白垩纪 新生界 阿根廷
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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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Terrestrial carbon sequestration in southeast and south-central United States
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作者 Fengxiang HAN M John Plodinec +3 位作者 Yi SU David L. Monts Zhongpei LI Baoshan XING 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期266-266,共1页
关键词 全球变暖 二氧化碳 温室效应 排放量
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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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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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Historical experience in the elimination of visceral leishmaniasis in the plain region of Eastern and Central China 被引量:15
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作者 Li-Ren Guan Zhong-Xing Wu 《Infectious Diseases of Poverty》 SCIE 2014年第1期81-91,80,共12页
Visceral leishmaniasis(VL)(kala-azar)was most seriously prevalent in the plain regions of eight provinces/municipalities in the eastern and central parts of China.In the early 1950s,the number of counties/cities endem... Visceral leishmaniasis(VL)(kala-azar)was most seriously prevalent in the plain regions of eight provinces/municipalities in the eastern and central parts of China.In the early 1950s,the number of counties/cities endemic for VL and the number of cases in the plain regions accounted for 60%and 80%,respectively,of the total numbers in the entire country.By implementing comprehensive control measures,including treatment of patients for eliminating the source of infection and spraying insecticide in endemic villages to kill sandflies,VL transmission has been brought under control in this region by the early 1960s,and no new infected cases have been found since 1983,achieving the goal of eliminating VL. 展开更多
关键词 Visceral leishmaniasis ELIMINATION Plain region eastern and central China
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Optimal redundant placement of PMUs in Indian power grid -- northern, eastern and north-eastern regions 被引量:2
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作者 Pathirikkat GOPAKUMAR G. Surya CHANDRA +1 位作者 M. Jaya Bharata REDDY Dusmata Kumar MOHANTA 《Frontiers in Energy》 SCIE CSCD 2013年第4期413-428,共16页
Effective utilization of renewable energy sources and efficient management of electric energy are essential for any developing countries like India. This can be envisioned through the implementation of concepts of sma... Effective utilization of renewable energy sources and efficient management of electric energy are essential for any developing countries like India. This can be envisioned through the implementation of concepts of smart grid (SG). One of the key requisites for SG implementation is that the grid should be completely observable. Renovation of conventional Indian power grid to a SG necessitates incorporation of the phasor measure- ment units (PMUs) in the present power grid measurement and monitoring system. Since the cost of PMU is high and any bus containing a PMU makes the neighboring connected buses observable, optimal placement of PMUs is very important for complete observability of the grid. This paper proposes optimal redundant geographical locations in the northern, eastern and north-eastern regions of Indian power grid for PMU placement. The PMUs installed in these geographical locations will make the grid completely observable and maintain the observability under the conditions of failure of some PMUs or branch outages. Integer linear programming has been used for finding the optimal PMU locations. The results proposed in this paper can be a stepping stone for revamping the Indian power grid to a SG ensuring complete observability during different contingency conditions. 展开更多
关键词 phasor measurement unit (PMU) smart grid (SG) Indian power grid northern region Indian power grid (NRIPG) eastern region Indian power grid (ERIPG) north- eastern region Indian power grid (NERIPG) redundancy integer linear programing (ILP)
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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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