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Discussion on the dynamic mechanism of Great North China area based on the observed stress data
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作者 冯向东 魏东平 陈棋福 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2005年第1期1-11,124,共12页
Based on the constrained data from the observed stress orientation and the observed stress regime, the tectonic stress fields of the Great North China area has been simulated by using the pseudo-3D finite element meth... Based on the constrained data from the observed stress orientation and the observed stress regime, the tectonic stress fields of the Great North China area has been simulated by using the pseudo-3D finite element method. The results indicate that the stress fields in this area are basically controlled by the push forces coming from the Pacific Plate and from the Tibet Plateau, and the WNW-ward action from the Pacific Plate play a more important role in North China plain block. In addition to that, the stress field in this area is also partly formed by the extension action from the mantle upwelling in perpendicular at the basin margins. 展开更多
关键词 Great north china area stress regime finite element method dynamic simulation
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The Source of Groundwater Recharge Based on Entropy Theory in the Arid Areas of North China 被引量:1
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作者 CHEN Jiansheng XU Yi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期390-391,共2页
Objective Any natural system is constantly exchanging material, energy and information with the environment, and all tkese processes follow the basic law of thermodynamics, with no exception of groundwater recharge a... Objective Any natural system is constantly exchanging material, energy and information with the environment, and all tkese processes follow the basic law of thermodynamics, with no exception of groundwater recharge and discharge process. On the basis of the principle of the first law of thermodynamics, the reverse geochemical simulation method is widely used in the study of groundwater recharge, runoff and drainage process. However, some studies only consider the material conservation in theprocess, but ignore the probability of the transformation. 展开更多
关键词 The Source of Groundwater Recharge Based on Entropy Theory in the Arid areas of north china
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THE POSSIBILITIES AND REALITIES ON THE REMANAGEMENT OF DESERTIFIED LANDS IN THE TRANSITIONAL ZONE BETWEEN THE DRY-FARMING AREA AND THE GRAZING AREA IN NORTH CHINA
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作者 朱震达 刘恕 杨有林 《Chinese Geographical Science》 SCIE CSCD 1991年第1期32-43,共12页
The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified ... The desertification process is rapidly developing at present and 61.5% of the land area in the zone are already desertified.Among the desertified lands, 26.9% are seriously desertified, 25% most seriously desertified and 47.4% are the lands where desertification is under way. They are caused by over-reclamation for farming, over-grazing, unreasonable collection of firewood,the destruction of vegetation and the misuse of water resources. Under the ecological environment in semi-arid zone,the degraded environment process possesses the ability of restoring to its original status as soon as the interruption of excessive human activities are eliminated. The fencing- and-self-cultivating method is an effective measure adopted universally in semi-arid zone to cure the desertified lands.The desertified lands can be readjusted and controlled easily if other controlling measures are supplemented. The fundamental ways to control desertification are to utilize rationally the resources, to readjust the existing 展开更多
关键词 desertified lands the transitional zone BETWEEN the dry-larming area and the GRAZING area remanagement north china.
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Determination of active units with different kinematic property and their activity pattern in North China based on the data from GPS remeasurements 被引量:2
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作者 杨国华 韩月萍 张凤兰 《Acta Seismologica Sinica(English Edition)》 CSCD 2001年第1期1-11,共11页
Based on the high-accuracy data obtained from the GPS measurements carried out in 1992, 1995 and 1996, the isochronous active units with different kinematic property inside the North China area have been distinguished... Based on the high-accuracy data obtained from the GPS measurements carried out in 1992, 1995 and 1996, the isochronous active units with different kinematic property inside the North China area have been distinguished, 4 active units and 1 transition zone with distinct differential movement have been determined. They are Ordos-Yinshan unit, Yanshan unit, Shanxi-Hebei-Shandong (Jin-Ji-Lu) unit, Jiaodong-Liaoning-Shandong (Jiao-Liao-Lu) unit and Yanshan-Hebei (Yan-Ji) transition zone. The relative movements among the neighboring units in this period have been given. ① The compressive movement between Ordos-Yinshan unit and Yanshan unit is not obvious with an amount of 0.4(1.3 mm/a.②in-Ji-Lu unit moves E40(S off the Ordos-Yinshan unit and the magnitude is 4.4(1.0 mm/a. ③elative to the Yan-Ji transition zone of differential movement, Yanshan unit shifts W38(N with a value of 2.4(1.3 mm/a and Jin-Ji-Lu unit moves eastward 35( by south with an amount of 2.3(0.9 mm/a. ④Jin-Ji-Lu unit has a tensional left-lateral movement of 4.7(1.4 mm/a in the direction of E37(S relative to Yanshan unit. ⑤ Some area near Tanlu belt which is located in the southern part of Jin-Ji-Lu block has a southward movement 14( by west with a magnitude of 1.5(1.1 mm/a off the Jin-Ji-Lu unit. ⑥ Relative to Jin-Ji-Lu unit, Jiao-Liao-Lu unit has a trend of clockwise movement with a tensional right-lateral motion at the north end which neighbors Yanshan unit and a compressive motion at the south end. It should be noted that the errors given in the paper are obtained based on the divergence among the displacements of the sites in the unit, rather than the value calculated from the displacement error of the sites. The analyzed results indicate that: ① Shanxi tectonic zone and Yan-Ji transition zone are the major tectonic active zones to show the frame and magnitude of interior relative movement in North China area, and others are the secondary tectonic active zones; ② The complete horizontal deformation in the North China area is not homogeneous nor successive; ③ The kinetic model of North China area might be (mantle dragging plus boundary coupling(. 展开更多
关键词 GPS measurement north china area active unit horizontal movement deformation mechanism
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Active blocks and their deformations derived from the velocity field in North China 被引量:1
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作者 黄立人 杨国华 王敏 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第1期79-91,共13页
Based on the horizontal movement velocities and their error estimations of 144 GPS stations in North China de-duced from the results obtained from multiple GPS measurements carried out in the period of 1992~2001, the ... Based on the horizontal movement velocities and their error estimations of 144 GPS stations in North China de-duced from the results obtained from multiple GPS measurements carried out in the period of 1992~2001, the horizontal deformation in the area is studied. The movements, entire deformations, local deformations, activity patterns and intensities along the boundary zones are derived. And then the risk of strong earthquake in the area is estimated. In the research, the horizontal displacement observations can be considered as the sum of three parts. The first part is the entire motion following Eurasian plate, which can be derived from NUVAL-IA model; the second part is the relative motions and deformations between the sub-tectonic blocks in the studied area, which can be derived from a set of displacement observations determined by the expanded QUAD method in the paper; the third part is the local deformations and errors in the sub-tectonic blocks, which can be described as the inhomoge-neous strains of the block. The method and results are introduced in detail in the paper. 展开更多
关键词 north china area horizontal movement application of QUAD method
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Earthquake-controlling Processes of Detachment Zones in Eastern North China 被引量:1
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作者 SUNAiqun NIUShuyin +2 位作者 SHAOJi'an HOUQuanlin ZHANGJianzhen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期283-290,共8页
The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersectio... The basin-and-range area in eastern North China is known for frequent occurrence of earthquakes, their great magnitudes and heavy losses thereby incurred. Seismic studies in the past usually emphasized the intersections, inflexions and branches of the faults. However, the intensities of many great earthquakes in this area do not show linear distribution, and the epicenters are horizontally dispersed at certain depths instead of along the strike of faults. Based on the sub-mantle plume studies made by authors in the past decade, it is thought that there exists an uplifted sub-mantle plume under the fault depression area in North China. The uplifting and intrusion of mantle materials caused the upper crust to be faulted, while low-velocity and high-velocity layers are alternatively distributed in the middle crust under the influence of the mantle and the lower crust. The middle and lower crust materials were detached from the top of the sub-mantle plume to the surroundings while the sub-mantle plume materials were detached outward. When the detached middle and lower crust come to the boundary of fault basins in the upper crust, they will be obstructed by the orogenic zone and the detachment will go slower. The shearing between them will cause the stress to accumulate and release alternatively, so that earthquakes occurred frequently in the areas of sub-mantle plume and its surroundings. 展开更多
关键词 sub-mantle plume detachment belt earthquake-controlling structure low-velocity and high-conductivity zones north china basin-and range area
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RESPONSE OF TRIASSIC SEQUENCE STRATIGRAPHY OF LOWER YANGTZE TO THE COLLISION BETWEEN THE YANGTZE PLATE AND THE NORTH CHINA PLATE 被引量:1
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作者 CHENG Rihui WANG Pujun LIU Wanzhu TANG Huafeng BAI Yunfeng KONG Qingying SONG Weihai 《Geotectonica et Metallogenia》 2005年第2期174-184,共11页
The characteristics of the Triassic sequences developed in the Lower Yangtze area display some great changes in both environment and climate. The change of environment was a transition from marine to continent via alt... The characteristics of the Triassic sequences developed in the Lower Yangtze area display some great changes in both environment and climate. The change of environment was a transition from marine to continent via alternating environments. The change of climate was a transition from tropic (torrid) to warm and wet climate via subtropic dry climate. The type variations of the sequences were from the marine sequences to the continental sequences, corresponding to the changes of environments and climates. Sequence 1 is a type II of sequence of mixed clastic and carbonate sediments; sequence 2 is a type I of sequence of carbonate platform; sequence 3 is a type I of sequence of carbonate tidal flat-salt lagoon, sequence 4 is a type II of sequence of lacustrine within marine layers, and sequence 5 is a sequence of lacustrine-swamp. The development, distribution and preservation of those sequences reveal the tectonic controls and their changes in the background. The collision between the Yangtze plate and the North China plate was a great geological event in the geological history, but the timing of the collision is still disputed. However, the characteristics of Triassic sequence stratigraphy and sea level changes in the Lower Yangtze area responded to this collision. The collision started at the beginning of middle Triassic and the great regression in the Lower Yangtze area started 22Ma earlier than those in the world. The tectonic conditions occurred before and during the collision controlled the development of sequences and type changes. 展开更多
关键词 三叠纪 序列 气候 构造运动 沉积岩
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Analysis on Variations of the Temperature and Precipitation in North Slope Area of the Western Tianshan in Recent 50 Years
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作者 YAO Fu-long,LI Hai-bing College of Chemistry and Biological Sciences,Yili Normal University,Yining 835000,China 《Meteorological and Environmental Research》 CAS 2011年第11期17-22,共6页
[Objective] The research aimed to analyze variation characteristics of the temperature and precipitation in north slope area of the Western Tianshan in recent 50 years.[Method] According to temperature and rainfall da... [Objective] The research aimed to analyze variation characteristics of the temperature and precipitation in north slope area of the Western Tianshan in recent 50 years.[Method] According to temperature and rainfall data from 1961 to 2010 at three meteorological stations in north slope area of the Western Tianshan,climate change in the zone in recent 50 years was analyzed by using linear trend analysis method and 5-year sliding average method.[Result] The temperature in north slope area of the Western Tianshan showed significant warming trend.The annual average temperature significantly increased at 0.3 ℃/10 a in recent 50 years.But rise rates of the temperature in different seasons were different:autumn> winter> spring> summer.The annual rainfall in north slope area of the Western Tianshan in recent 50 years overall presented relative increase trend.Seen from annual rainfall,it significantly increased at 16.9 mm/10 a.Seen from seasonal rainfall,except in autumn,rainfalls in other three seasons in the past 50 years all showed significant increase trends,with amplitude of 3.2-11.2 mm/10 a.The largest increase amplitude was in summer.After a small precipitation peak in the 1980s,autumn rainfall slightly declined in the past 20 years.[Conclusion] The climate in north slope area of the Western Tianshan become warm and wet. 展开更多
关键词 Climate change TEMPERATURE PRECIPITATION north slope area of the Western Tianshan china
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南海北部神狐海域细粒储层矿物组分对天然气水合物储集赋存的影响
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作者 徐小蕾 白辰阳 +3 位作者 苏丕波 马倩 张宇 梁金强 《地质论评》 CAS CSCD 北大核心 2024年第3期1205-1220,共16页
为了探明矿物类型对于天然气水合物成藏的影响,笔者等利用南海北部神狐海域W07站位样品及其水合物饱和度数据,进行XRD全岩和黏土矿物测试分析、比表面积分析以及束缚水能力综合分析。结果表明,海床下110~127 m(即110~127 mbsf,meters be... 为了探明矿物类型对于天然气水合物成藏的影响,笔者等利用南海北部神狐海域W07站位样品及其水合物饱和度数据,进行XRD全岩和黏土矿物测试分析、比表面积分析以及束缚水能力综合分析。结果表明,海床下110~127 m(即110~127 mbsf,meters below sea floor,海床以下深度)为非水合物储层段,海床下127~156 m为水合物储层段。通过XRD分析可知,高石英及长石含量,低伊蒙混层含量的层段,比表面积与束缚水能力较低,说明其具有相对较好的孔渗条件,为水合物的运移与储集提供了良好的空间条件,因此形成水合物储层段;而在高伊蒙混层的层段中,比表面积较大,束缚水能力较强,其对甲烷气体及流体的吸附和束缚能力较强,对水合物成藏起到潜在的封隔作用,成为非储层段,储层与非储层段纵向叠置序列有利于优质水合物储层的形成。本次研究总结了矿物组分与优质水合物储层之间的关系,并揭示两者存在的潜在成因联系,以期丰富水合物富集成藏的基础理论,对未来南海北部天然气水合物的商业化开发提供支持。 展开更多
关键词 南海北部 神狐海域 GMGS4 天然气水合物 黏土矿物
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五种气候生产力模型在华北土石山区的适用性分析
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作者 江睿 郑艺伟 +3 位作者 桑玉强 孙守家 张劲松 段志强 《中国农业气象》 CSCD 2024年第4期363-373,共11页
植被净初级生产力(Net Primary Productivity,NPP)是陆地植物的净固碳量,对于全球碳估算研究具有重要意义。华北土石山区作为中国林业工程重点区域,是典型的干旱半干旱气候区,准确估算该地区NPP大小及其变化特征对林业生态工程建设具有... 植被净初级生产力(Net Primary Productivity,NPP)是陆地植物的净固碳量,对于全球碳估算研究具有重要意义。华北土石山区作为中国林业工程重点区域,是典型的干旱半干旱气候区,准确估算该地区NPP大小及其变化特征对林业生态工程建设具有重要意义。本文基于河南小浪底森林生态系统国家野外科学观测研究站1980-2020年气候数据,利用Miami模型、Thornthwaite Memorial模型、Chikugo模型、朱志辉模型及周广胜模型共5种气候生产力模型估算,分析NPP的变化趋势,运用随机森林算法探讨NPP影响因素,并以区域MODISNPP数据为标准进行评价,以探究适合估算该地区NPP的气候生产力模型。结果表明:(1)华北土石山区年平均气温、最高气温、最低气温和降水量均呈上升趋势,变化速率分别为0.05℃×a^(-1)、0.04℃×a^(-1)、0.05℃×a^(-1)和1.58mm×a^(-1);年平均太阳辐射和平均相对湿度则呈下降趋势,变化速率分别为0.46MJ×m^(-2)×a^(-1)和0.17个百分点×a^(-1)。(2)采用5种模型计算的华北土石山区NPP均呈上升趋势,但NPP值存在差异,变化范围在739.35~958.48gC×m^(-2)×a^(-1),均值为862.19gC×m^(-2)×a^(-1)。其中Miami模型估算值最大(958.48gC×m^(-2)×a^(-1)),周广胜模型估算值最小(739.35gC×m^(-2)×a^(-1))。(3)随机森林算法表明,降水是影响该地区NPP的关键因子。适用性分析显示,周广胜模型估算值与MODIS NPP最接近,其相对误差、RMSE和MAE分别为1.45%、451.05gC×m^(-2)×a^(-1)和446.03gC×m^(-2)×a^(-1),且相关系数最大(0.49)。综上可知,周广胜模型更适宜该地区的NPP估算,在使用气候生产力模型估算华北土石山区NPP时,应优先考虑使用周广胜模型。 展开更多
关键词 植被净初级生产力 气候生产力模型 华北土石山区 MODISNPP 气候因子
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北方岩溶区降水入渗补给系数及补给机制:以羊庄岩溶水系统为例
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作者 康凤新 郑婷婷 +4 位作者 冯亚伟 徐秋晓 刘彬涛 王义生 李传谟 《地质科技通报》 CAS CSCD 北大核心 2024年第2期268-282,共15页
为建立北方岩溶区水文地质参数系列,提高岩溶地下水可采资源计算精度,笔者团队于20世纪80年代开始,在山东羊庄封闭式泉排型岩溶水系统开展了岩溶水均衡试验研究,积累了40余年的监测试验数据。根据长期野外水均衡要素观测资料,推导出裸... 为建立北方岩溶区水文地质参数系列,提高岩溶地下水可采资源计算精度,笔者团队于20世纪80年代开始,在山东羊庄封闭式泉排型岩溶水系统开展了岩溶水均衡试验研究,积累了40余年的监测试验数据。根据长期野外水均衡要素观测资料,推导出裸露型、半覆盖型和覆盖型岩溶区降水入渗补给系数计算公式,建立了岩溶区降水入渗补给系数α与降水量P和地下水位埋深D的相关方程,以及可调控的最大降水入渗补给系数系列,揭示了降水入渗补给过程与α变化机制。结果表明:α随水位埋深D的改变而改变,每个降水量P段分别对应一个最大降水入渗补给系数α_(max)和最大降水入渗补给量即补给极限G_(max),相应的水位埋深便是最佳水位埋深D_(critical)。D>D_(critical)时,包气带截留量随着水位埋深的增大而增大,α<α_(max);D<D_(critical)时,地表径流量随着地下水位埋深的减小而增大,α<α_(max)。不同的降水量段对应不同的D_(critical),降水量增大时,对应的α_(max)及D_(critical)也增大。在任意水位埋深时,G_(max)为蓄满产流临界降水量与包气带最大截流量之差。本研究解决了岩溶区降水入渗补给的关键科学问题,即揭示降水入渗补给机制、建立降水入渗补给系数与降水量和水位埋深的定量关系,提升了我国北方岩溶水资源基础性研究水平。 展开更多
关键词 岩溶水系统 包气带截留量 蓄满产流量 降水入渗补给系数 补给机制 羊庄盆地 北方岩溶区
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华北土石山区油松生长季夜间液流分配特征
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作者 胡蕾 贾剑波 +3 位作者 闫文德 王一帆 吴瑞乔 陈玉 《林业科学》 EI CAS CSCD 北大核心 2024年第4期91-98,共8页
【目的】通过对油松生长季夜间液流特征和环境驱动因素的研究,揭示夜间液流组分拆分特征,探讨夜间液流的组分与气象因子之间的相关关系,以及茎干补水对气象因子的响应,为华北土石山区水资源和水源涵养林管理决策提供理论依据。【方法】... 【目的】通过对油松生长季夜间液流特征和环境驱动因素的研究,揭示夜间液流组分拆分特征,探讨夜间液流的组分与气象因子之间的相关关系,以及茎干补水对气象因子的响应,为华北土石山区水资源和水源涵养林管理决策提供理论依据。【方法】以华北土石山区的油松作为研究对象,根据径阶大小选取18棵样树,在2014年生长季运用Granier热扩散探针技术(TDP)持续观测夜间液流,结合称重式蒸渗仪和自制微型蒸渗仪来计算蒸腾量,解析夜间液流的去向;并进行夜间液流与土壤含水量、大气温度、湿度及光合有效辐射等气象因子的相关分析,以确定主要驱动因素。【结果】在6—9月典型晴天,夜间液流速率都呈逐渐降低趋势,18:00—24:00的夜间液流速率高于00:00—05:00,夜间液流主要用于对白天失水过多的茎干进行补水,以至于在24:00时油松茎干储水量基本达到饱和,因此,00:00—05:00夜间液流速率趋于稳定;油松夜间液流用于茎干补水的比例(95.34%)显著高于用于夜间蒸腾量的比例(4.66%);油松夜间茎干补水量与饱和水汽压差呈极显著正相关(R^(2)=0.793,P<0.01),而对土壤含水量变化响应不敏感(R^(2)=0.105,P>0.05),表明夜间液流主要受饱和水汽压影响。【结论】华北土石山区的油松生长季夜间液流随着夜间时间的进行呈现逐渐降低的趋势;绝大部分的夜间液流用于夜间茎干补水,在气象因子中,饱和水汽压是驱动夜间茎干补水及夜间液流的重要因子(P<0.01)。 展开更多
关键词 夜间液流 分配特征 茎干补水 夜间蒸腾 华北土石山区
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1949年华北解放区南下干部集中整训之研究
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作者 代雅洁 《河北学刊》 北大核心 2024年第1期115-122,共8页
抽调大批干部南下是中共中央为夺取全国胜利而制定的重大战略决策,华北解放区的干部南下工作则构成全国“南下”战略中的关键性环节。在南下干部的动员、抽调等工作完成之后,华北解放区下辖各区的南下干部分别在石家庄、武安、菏泽、威... 抽调大批干部南下是中共中央为夺取全国胜利而制定的重大战略决策,华北解放区的干部南下工作则构成全国“南下”战略中的关键性环节。在南下干部的动员、抽调等工作完成之后,华北解放区下辖各区的南下干部分别在石家庄、武安、菏泽、威县、开平和正定等地开展了为期一个月左右的集中整训。此次集中整训目标明确,兼顾思想性与实用性,为南下干部适应从北方到南方、从老区到新区、从乡村到城市的工作实践转移奠定了基础。华北解放区南下干部集中整训过程中的组织整编、学习教育和军事训练,亦暗含着中国共产党理论与实践相结合、常规与运动相融合的干部生成与养成机制。 展开更多
关键词 南下干部 集中整训 华北解放区
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华北贸易总公司(1948.5—1949.7)探析
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作者 周芳冰 《西部学刊》 2024年第1期124-127,共4页
华北贸易总公司由解放战争时期晋察冀和晋冀鲁豫两区贸易公司合并发展而来,是统领华北解放区商贸的公营贸易公司。它在成立之时,于公司内部设置了五处三室,从纵向上建立了由上而下的垂直网络体系,下辖各级公司商店。为了完成“支援战争... 华北贸易总公司由解放战争时期晋察冀和晋冀鲁豫两区贸易公司合并发展而来,是统领华北解放区商贸的公营贸易公司。它在成立之时,于公司内部设置了五处三室,从纵向上建立了由上而下的垂直网络体系,下辖各级公司商店。为了完成“支援战争与发展生产”的中心任务,华北贸易总公司在建立并优化商情报告制度、仓库制度、转运栈制度等的基础上,对内平稳物价和进行物资交流,对外统一采购军用器材和民用必需品,推销各种剩余土产。平津解放之后,华北区的经济形势发生变化,中共中央最终撤销了华北贸易总公司。 展开更多
关键词 华北贸易总公司 华北解放区 发展生产
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“异变”时空下民族“隐言”的表达--以《中国文艺》为中心
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作者 高姝妮 《廊坊师范学院学报(社会科学版)》 2024年第2期62-67,共6页
《中国文艺》是沦陷时期北平最有影响的文学期刊,自创刊起便以刊载“纯文学”的办刊原则表明了疏离政治的文化立场,从而引起了北平有识文人的关注与认同。他们以此为文学阵地,秉持着民族心绪发表了大量的文学作品,间接表明了对日伪政权... 《中国文艺》是沦陷时期北平最有影响的文学期刊,自创刊起便以刊载“纯文学”的办刊原则表明了疏离政治的文化立场,从而引起了北平有识文人的关注与认同。他们以此为文学阵地,秉持着民族心绪发表了大量的文学作品,间接表明了对日伪政权的不满。然而在特殊的政治语境下,欲求文学的自救以重振民族精神,终究举步维艰,于是《中国文艺》以“隐言”的表达策略拓展民族启蒙话语空间,展写有识文人的民族情怀,呈现出民族文学的创作追求。在《中国文艺》所集结的作家的共同努力下,荒芜的北平文坛得到复苏,一定程度上增强了北平文坛的民族向心力。 展开更多
关键词 《中国文艺》 民族启蒙 “隐言” 华北沦陷区文学
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“运”而不“动”:华北沦陷区日伪铁路“爱护村运动”及其效果
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作者 符静 《河北学刊》 北大核心 2023年第6期73-80,共8页
抗日战争时期,侵华日军为了控制铁路沿线治安、打击反日力量,从1937年开始陆续将华北沦陷区铁路沿线的村庄划入“爱护村”范围,并开展了规模庞大的铁路“爱护村运动”。日伪通过各种手段动员铁路沿线村民尽心护路,但效果并不如预期。“... 抗日战争时期,侵华日军为了控制铁路沿线治安、打击反日力量,从1937年开始陆续将华北沦陷区铁路沿线的村庄划入“爱护村”范围,并开展了规模庞大的铁路“爱护村运动”。日伪通过各种手段动员铁路沿线村民尽心护路,但效果并不如预期。“爱护村”加重了华北农民的生活负担,其中无法解决的经费困境和农村劳动力匮乏问题,不仅使民众与日伪离心,也使日军与伪政权内部产生了矛盾分歧。这场由日伪运作、多方参与的“爱护村运动”在1945年最终随着日本战败而走向终结。 展开更多
关键词 “爱护村” 华北沦陷区 华北交通株式会社 “新民会”
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辽北开原地区晚古生代—早中生代混杂岩的厘定及其地质意义 被引量:1
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作者 郑常青 耿志忠 +2 位作者 段东 宋志伟 孙晓蕾 《世界地质》 CAS 2023年第3期444-460,共17页
辽宁省开原地区地处华北克拉通北缘,域内沿清河断裂出露一套中浅变质岩系,前人先后将其称为“辽河群”、“清河镇群”、“开原岩群”、“清河构造混杂岩”,但对其物质组成和形成时代尚未形成统一认识。通过系统总结不同岩石锆石U-Pb测... 辽宁省开原地区地处华北克拉通北缘,域内沿清河断裂出露一套中浅变质岩系,前人先后将其称为“辽河群”、“清河镇群”、“开原岩群”、“清河构造混杂岩”,但对其物质组成和形成时代尚未形成统一认识。通过系统总结不同岩石锆石U-Pb测年结果和地球化学数据,该套变质岩系是由新太古代、古元古代、晚二叠世-中三叠世不同时代地质体组成,其中早三叠世的海相沉积盖层和大面积的晚二叠世-中三叠世活动大陆边缘岛弧岩块指示古亚洲洋的闭合过程,碰撞背景下形成的变质英安岩(244 Ma)将古亚洲洋的最终闭合时间限定为中三叠世。综合对比区域地质资料,古亚洲洋在开原地区的俯冲闭合作用导致形成这套变质程度不同以新太古代华北板块基底岩石、晚二叠世-中三叠世火山岩为“岩块”,变粒岩、浅粒岩等变质碎屑岩为“基质”的混杂岩系。 展开更多
关键词 晚古生代-早中生代 华北克拉通北缘 混杂岩 古亚洲洋闭合 开原地区 辽北
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华北典型丘陵地区地下水水质特征及污染成因分析——以河南省安阳市龙安区为例 被引量:1
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作者 韩雪萌 蔡文倩 +3 位作者 王军强 李慧颖 徐香勤 田胜艳 《环境工程技术学报》 CAS CSCD 北大核心 2023年第3期992-1000,共9页
为探明华北典型丘陵地区——安阳市龙安区的地下水水质状况,共检测了龙安区内127个监测井的24项水质指标,开展区域地下水水质特征及污染成因研究;在水化学统计和水质评价的基础上,应用反距离权重空间插值法对污染物进行空间分布特征解析... 为探明华北典型丘陵地区——安阳市龙安区的地下水水质状况,共检测了龙安区内127个监测井的24项水质指标,开展区域地下水水质特征及污染成因研究;在水化学统计和水质评价的基础上,应用反距离权重空间插值法对污染物进行空间分布特征解析,并通过主成分分析法识别污染源。结果表明:龙安区浅层地下水化学类型多为HCO_(3)^(-)Ca型,区域内93.0%的地下水样品中NO_(3)^(-)浓度超过GB/T 14848—2017《地下水质量标准》中Ⅲ类标准限值,最大超标倍数为47.1倍。单因子污染指数评价结果显示,研究区地下水样品中NO_(3)^(-)污染指数最大值为48.10,其中27%的样品处于较重污染状态,19%处于严重至极重污染状态;SO_(4)^(2-)处于中度污染状态,Cl^(-)、NH_(4)^(+)、F-处于轻度污染状态。内梅罗综合污染指数评价结果显示,研究区地下水综合污染指数为0.01~34.69,地下水水质整体处于良好水平,但有4%的样品处于极差状态,主要分布于研究区中部。NO_(3)^(-)、NH_(4)^(+)、SO_(4)^(2-)、Cl^(-)浓度高值区主要分布于区域中部,且呈现中部高、东西低的分布特征;F-浓度高值区分布于地下水滞留区,且呈现西低东高的分布特征。污染成因分析结果表明,研究区地下水水质状况主要受区域水文地质条件、地下水地球化学特征和农业面源污染影响。 展开更多
关键词 地下水 水质特征 污染成因 安阳市龙安区 华北丘陵地区
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华北土石山区典型人工林空气负离子变化及其影响因子分析 被引量:1
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作者 张家兴 蒋丽娅 +4 位作者 高峻 贾长荣 李剑侠 桑玉强 张劲松 《林业科学研究》 CSCD 北大核心 2023年第2期61-69,共9页
[目的]探究华北土石山区典型人工林生长季与非生长空气负离子(NAI)的变化特征以及其影响因子的差异性,为揭示该地区不同季节影响NAI浓度的环境因子变化提供科学依据。[方法]利用河南黄河小浪底地球关键带国家野外科学观测研究站的空气... [目的]探究华北土石山区典型人工林生长季与非生长空气负离子(NAI)的变化特征以及其影响因子的差异性,为揭示该地区不同季节影响NAI浓度的环境因子变化提供科学依据。[方法]利用河南黄河小浪底地球关键带国家野外科学观测研究站的空气负离子、PM2.5、PM10和气象数据,分析该地区生长季与非生长季栓皮栎和侧柏的NAI变化特征,在此基础上,采用随机森林模型(RF)比较了影响NAI的主要环境因子及其重要性得分。[结果]生长季栓皮栎人工林NAI浓度日内变化呈单峰曲线,非生长季则不明显。生长季和非生长季侧柏人工林NAI浓度日内变化均呈单峰变化趋势,但峰值大小差异较大;观测期栓皮栎人工林平均NAI浓度(740.32 ion·cm^(−3))>侧柏(703.74 ion·cm^(−3))(p<0.01),其中,生长季栓皮栎人工林日均NAI浓度(858.94 ion·cm^(−3))>侧柏(724.33 ion·cm^(−3))(p<0.01);非生长季侧柏人工林日均NAI浓度(683.16ion·cm^(−3))>栓皮栎(621.70 ion·cm^(−3))(p<0.01);生长季空气温度(Ta)、相对湿度(RH)、饱和水汽压亏缺(VPD)、光合有效辐射(PAR)等气象因子均高于非生长季,而颗粒物(PM2.5、PM10)表现为非生长季高于生长季,且同时期PM10浓度>PM2.5浓度,风速(WS)生长季与非生长季差异不明显;随机森林模型显示,生长季影响栓皮栎和侧柏人工林NAI浓度的主要环境因子为VPD、PAR和WS,其重要性得分分别为20.22、15.08、14.71和25.08、16.76、16.49;非生长季影响栓皮栎人工林NAI浓度的主要环境因子为PM2.5、WS和PM10,其重要性得分分别为33.36、17.58和14.28,影响侧柏人工林NAI浓度的主要环境因子为WS、PM2.5和PM10,其重要性得分分别为17.51、15.89和14.62。[结论]华北土石山区生长季栓皮栎与侧柏NAI浓度日内变化均呈单峰曲线,非生长季栓皮栎NAI浓度变化不明显,而侧柏呈单峰曲线。栓皮栎和侧柏人工林NAI浓度差异显著,其中,生长季人工林的NAI浓度栓皮栎>侧柏,非生长季人工林的NAI浓度侧柏>栓皮栎,观测期内栓皮栎NAI浓度高于侧柏NAI浓度。影响该地区典型人工林NAI浓度的环境因子季节差异明显,生长季主要的环境因子是VPD和PAR,而非生长季的主要环境因子是颗粒物和WS。 展开更多
关键词 华北土石山区 典型人工林 空气负离子 随机森林模型 环境因子
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华北克拉通北缘孔兹岩带两期深熔石榴花岗岩地球化学特征及其地质意义 被引量:2
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作者 石强 李晨 +6 位作者 周煜欣 高鑫 李蕙萱 马人文 许严 赵忠海 徐仲元 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2023年第4期1090-1116,共27页
华北克拉通北缘孔兹岩带大青山地区和集宁—凉城地区石榴花岗岩与深熔源岩(泥质片麻岩)在野外空间上渐变过渡、密切共生。石榴花岗岩中含有大量的源岩包体、残留体、残留矿物相/转熔矿物相,深熔源岩中也存在大量的石榴花岗岩团块,这些... 华北克拉通北缘孔兹岩带大青山地区和集宁—凉城地区石榴花岗岩与深熔源岩(泥质片麻岩)在野外空间上渐变过渡、密切共生。石榴花岗岩中含有大量的源岩包体、残留体、残留矿物相/转熔矿物相,深熔源岩中也存在大量的石榴花岗岩团块,这些混合岩的岩性在宏观上具有不均一性。岩相学研究表明,石榴花岗岩与泥质片麻岩矿物组成相近,二者具有特征十分相似的石榴石,主要为残留矿物相/转熔矿物相。地球化学研究表明,石榴花岗岩与泥质片麻岩拟合程度较好,均具有高TFeO/MgO值和Al_(2)O_(3)质量分数,K_(2)O/Na_(2)O值和CaO质量分数存在较大变化,相对富集轻稀土元素和大离子亲石元素,相对亏损Ta、Nb、Ti和P等元素。与世界上典型的S型花岗岩成分偏离,大青山地区和集宁—凉城地区石榴花岗岩具有低SiO_(2)质量分数(50.30%~73.10%)和高MgO+TFeO质量分数(1.6%~14.8%)。研究认为偏离正常S型花岗岩的成分范围与石榴石残留体带入和幔源物质添加有关。结合前人资料,认为大青山地区和集宁—凉城地区石榴花岗岩由2.45~2.37 Ga和1.95~1.90 Ga两期深熔事件形成,与区域上幔源岩浆底侵时代相近,指示大青山地区和集宁—凉城地区石榴花岗岩是幔源基性岩浆侵入麻粒岩相变质沉积岩中引起变沉积岩发生大规模部分熔融的产物。 展开更多
关键词 孔兹岩带 大青山地区 集宁—凉城地区 石榴花岗岩 地球化学 华北克拉通
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