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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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Dynamic influence of Holocene characteristics on vadose water in typical region of central North China Plain 被引量:1
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作者 ZHANG Wei SHI Jian-sheng +3 位作者 XU Jian-ming LIU Ji-chao DONG Qiu-yao FAN Shu-xian 《Journal of Groundwater Science and Engineering》 2016年第3期247-258,共12页
In the typical region of central North China Plain, vadose sediments are Holocene sediment strata. With samples from field drillings, the study analyzes the sedimentary characteristics of vadose zone. The study takes ... In the typical region of central North China Plain, vadose sediments are Holocene sediment strata. With samples from field drillings, the study analyzes the sedimentary characteristics of vadose zone. The study takes the content of silty sand as the basis for sedimentary environment analysis, and the content of clay and sand as the sensitive indicator for sedimentary characteristics. Combining palynology analysis, the study divides vadose zone from top to bottom into diluvia oxbow lacustrine sediments, lacustrine sediments, lacustrine and swamp sediments, weak palaeohydrodynamic lacustrine sediments and alluvial sediments. Based on the sedimentary characteristics of Holocene strata, it analyzes the changes across depth of vadose zone water potential and matrix potential, obtaining the influence of vadose zone sedimentary characteristics on the migration of water in typical region of central North China Plain. 展开更多
关键词 Typical region of north china Plain Vadose zone Sedimentary characteristics Vadose zone water potential
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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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Application of the predictable model ofregional time-magnitude to North and Southwest China region 被引量:1
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作者 邵辉成 金学申 +3 位作者 杜兴信 王平 刘晨 刘志辉 《Acta Seismologica Sinica(English Edition)》 EI CSCD 1999年第3期321-323,2324-326,共6页
In this paper, the method which can combine different seismic data with the different precision and completeness, even the palaeo-earthquake data, has been applied to estimate the yearly seismic moment rate in the sei... In this paper, the method which can combine different seismic data with the different precision and completeness, even the palaeo-earthquake data, has been applied to estimate the yearly seismic moment rate in the seismic region. Based on this, the predictable model of regional time-magnitude has been used in North China and Southwest China. The normal correlation between the time interval of the events and the magnitude of the last strong earthquake shows that the model is suitable. The value of the parameter c is less than the average value of 0.33 that is obtained from the events occurred in the plate boundary in the world. It is explained that the correlativity between the recurrence interval of the earthquake and the magnitude of the last strong event is not obvious. It is shown that the continental earthquakes in China are different from that occurred in the plate boundary and the recurrence model for the continental events are different from the one for the plate boundary events. Finally the seismic risk analysis based on this model for North China and Southwest China is given in this paper. 展开更多
关键词 regional time-magnitude predictable model yearly seismic moment rate north chinaSouthwest china probability
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Characteristics of Horizontal Crustal Movement in the North China Region in the Last Decade 被引量:4
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作者 YangGuohua HanYueping WangMin 《Earthquake Research in China》 2004年第2期114-124,共11页
Based on high-precision data obtained in the past decade from GPS re-measurement in the North China Network, the Crustal Movement Observation Network of China (CMONOC) and GPS measurement along the Shanxi graben zone,... Based on high-precision data obtained in the past decade from GPS re-measurement in the North China Network, the Crustal Movement Observation Network of China (CMONOC) and GPS measurement along the Shanxi graben zone, the status and evolution of horizontal crustal movement in the North China region are analyzed. The results show that(1) the Yanshan tectonic zone (Zhangjiakou-Bohai Sea zone)is an active one with the largest horizontal strain in the North China region; The largest tendency differential movement of adjacent blocks is seen between the Yanshan block and the North China plain block; about 2mm/a (left lateral); (2) The significant horizontal differential movement along the boundaries of the North China region is characterized by right-lateral strike-slip movement at the middle-north segment on its west boundary (composed of Yinchuan and other active tectonic zones) and compressive movement at the south segment; while the Yinshan rift zone located along the west segment on its north boundary is dominated by tensile movement. Other boundaries and zones have no obvious differential movement; (3) On the whole, measurements of each period differ from one another, which might result from the nonlinear movement component as well as from the error effect. In the paper, results of the relative movement and strain in different periods are given for different blocks and boundary zones. 展开更多
关键词 中国北部 GPS 地质运动 动力变化 观测数据
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The quiescence of earthquakes with M_L≥4.0 as an important precursory characteristic prior to strong shocks in North China region
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作者 平建军 张青荣 +1 位作者 曹肃朝 边庆凯 《Acta Seismologica Sinica(English Edition)》 CSCD 2001年第4期471-480,共9页
关键词 north china region quiescence anomaly index for short-term prediction
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The Statistical Analysis of Migration of Strong Earthquakes─Taking the North China Region as an Example 被引量:1
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作者 QinChengzhi ZhouChenghu +1 位作者 PeiTao LiQuanlin 《Earthquake Research in China》 2004年第2期178-187,共10页
The migration of strong earthquakes is an important research topic because the migration phenomena reflect partly the seismic mechanism and involve the prediction of tendency of seismic activity. Research on migration... The migration of strong earthquakes is an important research topic because the migration phenomena reflect partly the seismic mechanism and involve the prediction of tendency of seismic activity. Research on migration of strong earthquakes has mostly focused on finding the phenomena. Some attempts on getting regularity were comparatively subjective. This paper suggests that there should be indices of migration in earthquake dataset and the indexes should have statistical meaning if there is regularity in the migration of strong earthquakes. In this study, three derivative attributes of migration, i.e., migration orientation, migration distance and migration time interval, were statistically analyzed. Results in the North China region show that the migration of strong earthquakes has statistical meaning. There is a dominant migration orientation (W by S to E by N), a dominant distance (≤100km and on the confines of 300~700km), and a dominant time interval (≤1a and on the confines of 3~4a). The results also show that the migration will differ slightly with different magnitude range or earthquake activity phase. 展开更多
关键词 数据统计分析 中国北部 地震运动 南-北地震带
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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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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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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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Elementary Research on Activity Behavior of the Crust in Funan-Huoqiu Area, Southern Border of the North China Active Block Region
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作者 Yao Daquan Liu Jiacan 《Earthquake Research in China》 2005年第4期371-380,共10页
The Funan-Huoqiu area is located in the border tectonic belt between the North China and South China active block regions. By means of seismological and geological surveys and synthetic analysis, evidences of tectonic... The Funan-Huoqiu area is located in the border tectonic belt between the North China and South China active block regions. By means of seismological and geological surveys and synthetic analysis, evidences of tectonic deformation in lower intensity have been found in the area since Late Pleistocene, where small earthquakes are distributed linearly along the main faults, conjugate shear joints are developed in the Upper Pleistocene nearby the faults. In the south of the studied region, fissures with different lengths, widths and directions occurred successively in Gushi, Huoqiu, Funan and other places of the area, in the 1970’s, and the direction of the fissures is approximately consistent with that of the Feizhong fault and Wanglaorenji fault. The authors hold that the clustering of small earthquakes, the conjugate shear joints developed in the Upper Pleistocene, the crumpled deformation of materials on fault plane, and the development of modern surface fissures in the area all reflect that the energy in the crust was slowly released, and that the weak deformation took place in corresponding faults. There was only one destructive earthquake taking place in the area (the Jiangkouji {M_S43/4} earthquake). Altogather, there has been weak activity in the area since the Late Quaternary, and it is mainly shown as a creep-slip. 展开更多
关键词 地震 地壳结构 活动性 地质特征 地球构造
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A case study on occurrence mechanism of fresh groundwater in the north of Alashan of the arid region of northwestern China
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《Global Geology》 1998年第1期47-48,共2页
关键词 A case study on occurrence mechanism of fresh groundwater in the north of Alashan of the arid region of northwestern china CASE
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Study on the Method of Short-Term Synthetic Earthquake Prediction in the North China Region
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作者 PingJianjun ZhangYongxian +4 位作者 ZhangQingrong LiuSuying ChenJianguo HuangWanfa MiXuemei 《Earthquake Research in China》 2004年第2期188-199,共12页
Based on the extraction and calculation of the short-term seismic precursory information magnitude from the 114 major precursory observations in the North China region, and together with consideration of factors such ... Based on the extraction and calculation of the short-term seismic precursory information magnitude from the 114 major precursory observations in the North China region, and together with consideration of factors such as geological structure, seismicity, crustal thickness, and in particular, the current geodynamics of the region, the authors studied the time-space evolution characteristics of the short-term earthquake precursory information magnitude and its relationship with earthquakes and proposed the index and method for the short-term synthetic prediction of earthquakes with M S≥5.0 in the North China region. The inspection through R-value shows that the method is effective to a certain extent for earthquake prediction. 展开更多
关键词 中国北部 短时地震 信息场 变化特征 人工预报方法
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Investigating the Transport Mechanism of PM2.5 Pollution during January 2014 in Wuhan, Central China 被引量:14
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作者 Miaomiao LU Xiao TANG +9 位作者 Zifa WANG Lin WU Xueshun CHEN Shengwen LIANG Hui ZHOU Huangjian WU Ke HU Longjiao SHEN Jia YU Jiang ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第11期1217-1234,I0012-I0017,共19页
Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different f... Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different from other megacities, like Beijing. Both the growth rates and decline rates of PM2.5 concentrations in Wuhan were lower than those in Beijing, but the monthly PM2.5 value was approximately twice that in Beijing. Furthermore, the sharp increases of PM2.5 concentrations were often accompanied by strong winds. A high-precision modeling system with an online source-tagged method was established to explore the formation mechanism of five haze episodes. The long-range transport of the polluted air masses from the North China Plain (NCP) was the main factor leading to the sharp increases of PM2.5 concentrations in Wuhan, which contributed 53.4% of the monthly PM2.5 concentrations and 38.5% of polluted days. Furthermore, the change in meteorological conditions such as weakened winds and stable weather conditions led to the accumulation of air pollutants in Wuhan after the long-range transport. The contribution from Wuhan and surrounding cities to the PM2.5 concentrations was determined to be 67.4% during this period. Under the complex regional transport of pollutants from surrounding cities, the NCP, East China, and South China, the five episodes resulted in 30 haze days in Wuhan. The findings reveal important roles played by transregional and intercity transport in haze formation in Wuhan. 展开更多
关键词 HAZE POLLUTION regional transport WUHAN north china PLAIN source-tagged method
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Influence of the Asian-Pacific Oscillation on Spring Precipitation over Central Eastern China 被引量:12
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作者 周波涛 赵平 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第3期575-582,共8页
The linkage between the Asian-Pacific oscillation (APO) and the precipitation over central eastern China in spring is preliminarily addressed by use of the observed data. Results show that they correlate very well, ... The linkage between the Asian-Pacific oscillation (APO) and the precipitation over central eastern China in spring is preliminarily addressed by use of the observed data. Results show that they correlate very well, with the positive (negative) phase of APO tending to increase (decrease) the precipitation over central eastern China. Such a relationship can be explained by the atmospheric circulation changes over Asia and the North Pacific in association with the anomalous APO. A positive phase of APO, characterized by a positive anomaly over Asia and a negative anomaly over the North Pacific in the upper-tropospheric temperature, corresponds to decreased low-level geopotential height (H) and increased high-level H over Asia, and these effects are concurrent with increased low-level H and decreased high-level H over the North Pacific. Meanwhile, an anticyclonic circulation anomaly in the upper troposphere and a cyclonic circulation anomaly in the lower troposphere are introduced in East Asia, and the low-level southerly wind is strengthened over central eastern China. These changes provide advantageous conditions for enhanced precipitation over central eastern China. The situation is reversed in the negative phase of APO, leading to reduced precipitation in this region. 展开更多
关键词 Asian-Pacific oscillation precipitation over central eastern china Asia and the north Pacific atmospheric circulations
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The 144–140 Ma Mafic Dykes in North China and Northeast China Indicating Regional Extensional Tectonic Setting 被引量:1
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作者 XU Huan LIU Yongqing +1 位作者 KUANG Hongwei PENG Nan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期353-354,共2页
Objective Previous studies indicate that the North China Craton(NCC)had undergone the loss of thickened lithosphere and fundamental change of physical and chemical property of lithospheric mantle(the destruction of... Objective Previous studies indicate that the North China Craton(NCC)had undergone the loss of thickened lithosphere and fundamental change of physical and chemical property of lithospheric mantle(the destruction of NCC)during the Mesozoic.The peak period of the destruction of NCC is estimated to be 130 Ma,accompanied by widespread metamorphic core complex,rift basins,A-type granites and mafic dykes. However, it remains greatly controversial on the tectonic setting of NCC in the pre- 130Ma. 展开更多
关键词 NCC Ma Mafic Dykes in north china and northeast china Indicating regional Extensional Tectonic Setting the 144 SHRIMP
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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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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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Analysis of Externality of Rural Labor Force Flow in Central and Western Regions of China and Benefit Compensation 被引量:1
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作者 Xin LI Haijing HU 《Asian Agricultural Research》 2013年第9期64-67,共4页
According to the theories of institutional economics and development economics,the positive and negative externality of rural labor force flowing from central and western regions and into eastern regions of China were... According to the theories of institutional economics and development economics,the positive and negative externality of rural labor force flowing from central and western regions and into eastern regions of China were analyzed,and then it was proposed that it is necessary to positive externality,rather than take"household register"measures to solve the problem simply. 展开更多
关键词 RURAL LABOR force FLOW EXTERNALITY central and wes
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