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Study on Hysteretic Bond Mechanisms of Plain Round Bar
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作者 Cheng Hong Hideo Araki 《Journal of Civil Engineering and Architecture》 2015年第7期875-884,共10页
Plain round bars were commonly used as main bars in the design of RC (reinforced concrete) buildings prior to the 1970s. According to previous research investigating the seismic performance of reinforced concrete me... Plain round bars were commonly used as main bars in the design of RC (reinforced concrete) buildings prior to the 1970s. According to previous research investigating the seismic performance of reinforced concrete members constructed with plain round bars, the strength of those members did not reach the calculated flexural strength due to bond slippage of main bars before yielding. It is important, therefore, to investigate the hysteretic bond mechanisms of plain round bars in concrete. In this research, analytical models were proposed to predict hysteretic bond-slip mechanisms between plain round bar and concrete depending on the results of experiments performed by the authors. In addition, the energy absorption capacity and the equivalent viscous damping factors obtained from the experimental results and analytical models are discussed. As a result of comparisons between the experimental data and the analysis models, good agreements were obtained. 展开更多
关键词 Analytical models energy absorption capacity equivalent viscous damping factor epoxy resin injection plain roundbar.
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Optimizing groundwater recharge plan in North China Plain to repair shallow groundwater depression zone, China 被引量:2
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作者 Rui-fang Meng Hui-feng Yang +4 位作者 Xi-lin Bao Bu-yun Xu Hua Bai Jin-cheng Li Ze-xin Liang 《Journal of Groundwater Science and Engineering》 2023年第2期133-145,共13页
The North China Plain is one of the main grain producing areas in China. However, overexploitation has long been unsustainable since the water supply is mainly from groundwater. Since 2014,the South-to-North Water Div... The North China Plain is one of the main grain producing areas in China. However, overexploitation has long been unsustainable since the water supply is mainly from groundwater. Since 2014,the South-to-North Water Diversion Project's central route has been charted to the integrated management of water supply and over-exploitation, which has alleviated the problem to a certain extent. Although the Ministry of Water Resources has made many efforts on groundwater recharge since 2018 most of which have been successful, the recharge has not yet been sufficiently focused on the repair of shallow groundwater depression zones. It still needs further optimization. This paper discusses this particular issue,proposes optimized recharge plan and provides the following recommendations:(1) Seven priority target areas are selected for groundwater recharge in alluvial and proluvial fans in the piedmont plain, and the storage capacity is estimated to be 181.00×10~8 m~3;(2) A recharge of 31.18×10~8 m~3/a is required by 2035 to achieve the repair target;(3) It is proposed to increase the recharge of Hutuo River, Dasha River and Tanghe River to 19.00×10~8 m~3/a and to rehabilitate Gaoliqing-Ningbailong Depression Zone;increase the recharge of Fuyang River, Zhanghe River and Anyang River to 7.05×10~8 m~3/a and rehabilitate Handan Feixiang-Guangping Depression Zone;increase the recharge of Luanhe River by 0.56×10~8 m~3/a and restore Tanghai Depression Zone and Luanan-Leting Depression Zone;moderately reduce the amount of water recharged to North Canal and Yongding River to prevent excessive rebound of groundwater;(4) Recharge through well is implemented on a pilot basis in areas of severe urban ground subsidence and coastal saltwater intrusion;(5) An early warning mechanism for groundwater quality risks in recharge areas is established to ensure the safety. The numerical groundwater flow model also proves reasonable groundwater level restoration in the depression zones by 2035. 展开更多
关键词 North China plain Groundwater recharge Groundwater depression zone Recharge target areas Storage capacity Recharge source Recharge effectiveness
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Changes in groundwater resources and their influencing factors in Songnen Plain, China 被引量:1
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作者 Qiang Liu Xiao-dong Guo +4 位作者 Chang-qi Wang Nan Lin Hui-rong Zhang Lin Chen Yan Zhang 《Journal of Groundwater Science and Engineering》 2023年第3期207-220,共14页
The Songnen Plain is a crucial agricultural area in China,and in the past 20 years,a large number of dry fields have been developed into paddy fields in order to improve land output efficiency.As a result,the effectiv... The Songnen Plain is a crucial agricultural area in China,and in the past 20 years,a large number of dry fields have been developed into paddy fields in order to improve land output efficiency.As a result,the effective irrigation area of agriculture has increased annually,and the conversion mode and quantity between surface water and groundwater have changed considerably.It is essential to identify the changes in groundwater resources and their influencing factors for the sustainable development of economy and society.This study evaluates groundwater resources in the Songnen Plain using the water balance method based on meteorological,hydrological and groundwater monitoring data from 2000 to 2020.The results 3 show that the groundwater resources in the region amount to 15.945 billion m with precipitation infiltration being the most important component,accounting for 73.09%,which is followed surface water irrigation infiltration and river and ditch infiltration,constituting 14.55%and 10.32%,respectively.Different factors influence groundwater resources in different periods.Compared to 1985,the increase of surface water irrigation infiltration is the primary factor responsible for the increase of groundwater resources,while other recharge sources have decreased during the same period.Compared to 2005,all groundwater resources have increased,with the increase of surface water irrigation infiltration and river channel infiltration being the primary factors. 展开更多
关键词 Songnen plain Groundwater resources PRECIPITATION IRRIGATION INFILTRATION
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Determine the most appropriate strategy for groundwater management in arid and semi-arid regions, Abhar Plain, Iran 被引量:1
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作者 Fatemeh Einlo Mohammad Reza Ekhtesasi +1 位作者 Mehdi Ghorbani Parviz Abdinejad 《Journal of Groundwater Science and Engineering》 2023年第2期97-115,共19页
Due to growing demand and reduction of water resources and increasing pollution of water,driven by dramatic population and economic growth, arid and semi-arid land's imminent water problems are nowadays aggravatin... Due to growing demand and reduction of water resources and increasing pollution of water,driven by dramatic population and economic growth, arid and semi-arid land's imminent water problems are nowadays aggravating. This study aims to determine the most appropriate management strategies for balancing the Abhar plain aquifer using the SWOT coupled with AHP technique. The results indicate that weaknesses prevail over strengths as well as threats over opportunities. The placement in the quarter of weaknesses-threats with a defensive strategy indicates the critical condition of the Abhar plain aquifer. The most appropriate solutions to achieve the goal of balancing the groundwater were prioritized by AHP method. According to results, improper management of water consumption with a weight of 72.5% is the most destructive factor in reducing groundwater resources. Among the types of consumption, the effect of an agricultural factor carries a weight of 74.2%. The exploitation of illegal wells, overdraft of exploitation license provisions of wells, reduction of precipitation and traditional irrigation methods were selected as the destructive factors causing the deteriration of groundwater resources. Also, with filling the illegal wells,changing the type of cultivation and greenhouse crops cultivation, installing a smart water meter,observance the provisions of the water exploitation license, implementing integrated pressurized irrigation systems, benefiting from suitable climatic conditions and geographical location for cultivating and developing the low-water use species and industries and on the other hand, with implementing artificial recharge to control the surface water resources and reduce abstraction from groundwater aquifers, the adverse trend of Abhar Plain groundwater resources can be controlled. 展开更多
关键词 Groundwater balancing Model SWOT AHP Abhar plain aquifer
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Effects of Groundwater with Various Salinities on Evaporation and Redistribution of Water and Salt in Saline-sodic Soils in Songnen Plain,Northeast China
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作者 ZHU Wendong ZHAO Dandan +6 位作者 YANG Fan WANG Zhichun DONG Shide AN Fenghua MA Hongyuan ZHANG Lu TIBOR Tóth 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1141-1152,共12页
Groundwater mineralization is one of the main factors affecting the transport of soil water and salt in saline-sodic areas.To investigate the effects of groundwater with different levels of salinity on evaporation and... Groundwater mineralization is one of the main factors affecting the transport of soil water and salt in saline-sodic areas.To investigate the effects of groundwater with different levels of salinity on evaporation and distributions of soil water and salt in Songnen Plain,Northeast China,five levels of groundwater sodium adsorption ration of water(SARw)and total salt content(TSC mmol/L)were conducted in an oil column lysimeters.The five treated groundwater labeled as ST0:0,ST0:10,ST5:40,ST10:70 and ST20:100,were prepared with NaCl and CaCl2 in proportion,respectively.The results showed the groundwater evaporation(GWE)and soil evaporation(SE)increased firstly and then decreased with the increase of groundwater salinity.The values of GWE and SE in ST10:70 treatment were the highest,which were 2.09 and 1.84 times the values in the ST0:0 treatment with the lowest GWE and SE.There was a positive linear correlation between GWE and the Ca^(2+)content in groundwater,with R^(2)=0.998.The soil water content(SWC)of ST0:0 treatment was significantly(P<0.05)less than those of other treatments during the test.The SWC of the ST0:0 and ST0:10 treatments increased with the increase of soil depth,while the other treatments showed the opposite trend.Statistical analysis indicated the SWC in the 0–60 cm soil layer was positively correlated with the groundwater TSC and its ion contents during the test.Salt accumulation occurred in the topsoil and the salt accumulation in the 0–20 cm soil layer was significantly(P<0.05)greater than that in the subsoil.This study revealed the effects of the salinity level of groundwater,especially the Ca^(2+)content and TSC of groundwater,on the GWE and distributions of soil water and salt,which provided important support for the prevention and reclamation of soil salinization and sodificaton in shallow groundwater regions. 展开更多
关键词 groundwater evaporation sodium adsorption ratio total salt content ion composition soil salinization water and salt dynamics Songnen plain China
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Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture
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作者 Maria Kaleem Erum Bashir +2 位作者 Shahid Naseem Tahir Rafique Bushra Shahab 《Acta Geochimica》 EI CAS CSCD 2024年第2期214-234,共21页
This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by mu... This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical data.The outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the region.Twenty-five soil samples were collected,mainly from the arable land of the Porali Plain.After drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric analysis.Esti-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial distribution.The granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt type.Weathering indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of alteration.These indices reflect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr ratios.Assessment of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the soils.The correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type mineralization.Weathering may result in the undesirable accumulation of certain trace elements which adversely affects crops. 展开更多
关键词 Weathering indices Pollution indices ACCUMULATION Repercussions Trace elements Multivariate analyses Porali plain BALOCHISTAN
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Using neural network modeling to improve the detection accuracy of land subsidence due to groundwater withdrawal
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作者 Ali M.RAJABI Ali EDALAT +1 位作者 Yasaman ABOLGHASEMI Mahdi KHODAPARAST 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2320-2333,共14页
Despite the high efficiency of remote sensing methods for rapid and large-scale detection of subsidence phenomena,this technique has limitations such as atmospheric impact and temporal and spatial decorrelation that a... Despite the high efficiency of remote sensing methods for rapid and large-scale detection of subsidence phenomena,this technique has limitations such as atmospheric impact and temporal and spatial decorrelation that affect the accuracy of the results.This paper proposes a method based on an artificial neural network to improve the results of monitoring land subsidence due to groundwater overexploitation by radar interferometry in the Aliabad plain(Central Iran).In this regard,vertical ground deformations were monitored over 18 months using the Sentinel-1A SAR images.To model the land subsidence by a multilayer perceptron(MLP)artificial neural network,four parameters,including groundwater level,alluvial thickness,elastic modulus,and transmissivity have been applied.The model's generalizability was assessed using data derived for 144 days.According to the results,the neural network estimates the land subsidence at each ground point with an accuracy of 6.8 mm.A comparison between the predicted and actual values indicated a significant agreement.The MLP model can be used to improve the results of subsidence detection in the study area or other areas with similar characteristics. 展开更多
关键词 DINSAR Land subsidence Groundwater withdrawal Aliabad plain Artificial neural network
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Optimization of inter-seasonal nitrogen allocation increases yield and resource-use efficiency in a water-limited wheat-maize cropping system in the North China Plain
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作者 Xiaonan Zhou Chenghang Du +7 位作者 Haoran Li Zhencai Sun Yifei Chen Zhiqiang Gao Zhigan Zhao Yinghua Zhang Zhimin Wang Ying Liu 《The Crop Journal》 SCIE CSCD 2024年第3期907-914,共8页
Winter wheat–summer maize cropping system in the North China Plain often experiences droughtinduced yield reduction in the wheat season and rainwater and nitrogen(N)fertilizer losses in the maize season.This study ai... Winter wheat–summer maize cropping system in the North China Plain often experiences droughtinduced yield reduction in the wheat season and rainwater and nitrogen(N)fertilizer losses in the maize season.This study aimed to identify an optimal interseasonal water-and N-management strategy to alleviate these losses.Four ratios of allocation of 360 kg N ha^(-1)between the wheat and maize seasons under one-time presowing root-zone irrigation(W0)and additional jointing and anthesis irrigation(W2)in wheat and one irrigation after maize sowing were set as follows:N1(120:240),N2(180:180),N3(240:120)and N4(300:60).The results showed that under W0,the N3 treatment produced the highest annual yield,crop water productivity(WPC),and nitrogen partial factor productivity(PFPN).Increased N allocation in wheat under W0 improved wheat yield without affecting maize yield,as surplus nitrate after wheat harvest was retained in the topsoil layers and available for the subsequent maize.Under W2,annual yield was largest in the N2 treatment.The risk of nitrate leaching increased in W2 when N application rate in wheat exceeded that of the N2 treatment,especially in the wet year.Compared to W2N2,the W0N3 maintained 95.2%grain yield over two years.The WPCwas higher in the W0 treatment than in the W2 treatment.Therefore,following limited total N rate,an appropriate fertilizer N transfer from maize to wheat season had the potential of a“triple win”for high annual yield,WPCand PFPN in a water-limited wheat–maize cropping system. 展开更多
关键词 Cropping system Water-saving irrigation North China plain Nitrogen optimization Sustainable intensification
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Analysis on the turning point of dynamic in-plane compressive strength for a plain weave composite
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作者 Xiaoyu Wang Zhixing Li +2 位作者 Licheng Guo Zhenxin Wang Jiuzhou Zhao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期485-495,共11页
Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate ... Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate of composites was established. Then the upper limit of strain rate, restricted by stress equilibrium and constant loading rate, was rationally estimated and confirmed by tests. Within the achievable range of 0.001/s-895/s, it was found that the strength increased first and subsequently decreased as the strain rate increased. This feature was also reflected by the turning point(579/s) of the bilinear model for strength prediction. The transition in failure mechanism, from local opening damage to completely splitting destruction, was mainly responsible for such strain rate effects. And three major failure modes were summarized under microscopic observations: fiber fracture, inter-fiber fracture, and interface delamination. Finally, by introducing a nonlinear damage variable, a simplified ZWT model was developed to characterize the dynamic mechanical response. Excellent agreement was shown between the experimental and simulated results. 展开更多
关键词 plain weave composite Dynamic strength Quantitative criterion Turning point Failure mechanism
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Improved simulation of winter wheat yield in North China Plain by using PRYM-Wheat integrated dry matter distribution coefficient
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作者 Xuan Li Shaowen Wang +6 位作者 Yifan Chen Danwen Zhang Shanshan Yang Jingwen Wang Jiahua Zhang Yun Bai Sha Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1381-1392,共12页
The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass... The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass×harvest index(HI)”method to simulate regional-scale winter wheat yield.However,spatiotemporal differences in HI contribute to inaccuracies in yield simulation at the regional scale.Time-series dry matter partition coefficients(Fr)can dynamically reflect the dry matter partition of winter wheat.In this study,Fr equations were fitted for each organ of winter wheat using site-scale data.These equations were then coupled into a process-based and remote sensingdriven crop yield model for wheat(PRYM-Wheat)to improve the regional simulation of winter wheat yield over the North China Plain(NCP).The improved PRYM-Wheat model integrated with the fitted Fr equations(PRYM-Wheat-Fr)was validated using data obtained from provincial yearbooks.A 3-year(2000-2002)averaged validation showed that PRYM-Wheat-Fr had a higher coefficient of determination(R^(2)=0.55)and lower root mean square error(RMSE=0.94 t ha^(-1))than PRYM-Wheat with a stable HI(abbreviated as PRYM-Wheat-HI),which had R^(2) and RMSE values of 0.30 and 1.62 t ha^(-1),respectively.The PRYM-Wheat-Fr model also performed better than PRYM-Wheat-HI for simulating yield in verification years(2013-2015).In conclusion,the PRYM-Wheat-Fr model exhibited a better accuracy than the original PRYM-Wheat model,making it a useful tool for the simulation of regional winter wheat yield. 展开更多
关键词 dry matter partition remote sensing model winter wheat yield North China plain
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New Rural Community Construction or Retention Development:A Comparative Analysis of Rural Settlement Transition Mechanism in Plain Agriculture Area of China Based on Actor Network Theory
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作者 QU Yanbo DONG Xiaozhen +1 位作者 MA Wenqiu ZHAO Weiying 《Chinese Geographical Science》 SCIE CSCD 2024年第3期436-452,共17页
It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical fra... It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical framework for the study of RST.Taking two typical villages with different transition paths in rural areas of North China Plain as examples,this paper reveals the mechanism of RST and makes a comparative analysis.The results show that:1)after identifying problems and obligatory passage point,key actors recruit heterogeneous actors into the actor network by entrusting them with common interests,and realize RST under the system operation.2)Rural settlements under different transition paths have similarities in the problems to be solved,collective actions and policy factors,but there are differences in the transition process,mechanism and effect.The actor network and mechanism of RST through the path of new rural community construction are more complex and the transition effect is more thorough.In contrast,the degree of RST of retention development path is limited if there is no resource and location advantage.3)Based on the applicable conditions of different paths,this paper designs a logical framework of‘Situation-Structure-Behavior-Result’to scientifically guide the identification of RST paths under the background of rural revitalization. 展开更多
关键词 rural settlement transition(RST) actor network theory(ANT) transition path transition mechanism plain area China
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Seismogenic model of the 2023 M_(W)5.5 Pingyuan earthquake in North China Plain and its tectonic implications
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作者 Shiguang Wang Libo Han +5 位作者 Junju Xie Liping Fan Xiang Huang Jinmeng Bi Hongfeng Yang Lihua Fang 《Earthquake Science》 2024年第6期499-513,共15页
The 6 August 2023 M_(W)5.5 Pingyuan earthquake is the largest earthquake in the central North China Plain(NCP)over the past two decades.Due to the thick sedimentary cover,no corresponding active faults have been repor... The 6 August 2023 M_(W)5.5 Pingyuan earthquake is the largest earthquake in the central North China Plain(NCP)over the past two decades.Due to the thick sedimentary cover,no corresponding active faults have been reported yet in the epicenter area.Thus,this earthquake presents a unique opportunity to delve into the buried active faults beneath the NCP.By integrating strong ground motion records,high-precision aftershock sequence relocation,and focal mechanism solutions,we gain insights into the seismotectonics of the Pingyuan earthquake.The aftershocks are clustered at depths ranging from 15 to 20 km and delineate a NE-SW trend,consistent with the distribution of ground motion records.A NE-SW nodal plane(226°)of the focal mechanism solutions is also derived from regional waveform inversion,suggesting that the mainshock was dominated by strike-slip motion with minor normal faulting component.Integrating regional geological data,we propose that an unrecognized fault between the NE-SW trending Gaotang and Lingxian-Yangxin faults is the seismogenic fault of this event.Based on the S-wave velocity structure beneath the NCP,this fault probably extends into the lower crust with a high angle.Considering the tectonic regime and stress state,we speculate that the interplay of shear strain between the Amurian and South China blocks and the hot upwelling magma from the subducted paleo Pacific flat slab significantly contributed to the generation of the Pingyuan earthquake. 展开更多
关键词 Pingyuan earthquake aftershock relocation focal mechanism S-wave velocity structure North China plain
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Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China
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作者 ZHANG Sumei ZHANG Yuan ZHAO Hongmei 《Chinese Geographical Science》 SCIE CSCD 2024年第3期548-563,共16页
The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate ... The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data. 展开更多
关键词 crop residue burning burned area Sentinel-2 Multi Spectral Instrument(MSI) logistic regression Songnen plain China
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Formation mechanisms and resource potential of carbonate geothermal reservoirs in the Beijing-Tianjin-Hebei plain
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作者 Xinwei Wang Tinghao Wang +3 位作者 Nanan Gao Xiang Mao Lu Luo Xingchen Lu Haiquan Li 《Energy Geoscience》 EI 2024年第3期175-188,共14页
Investigating the formation mechanisms of carbonate geothermal reservoirs is of theoretical and practical significance for summarizing the formation pattern of geothermal resources and further guiding their effective ... Investigating the formation mechanisms of carbonate geothermal reservoirs is of theoretical and practical significance for summarizing the formation pattern of geothermal resources and further guiding their effective exploitation.The Beijing-Tianjin-Hebei Plain(BTHP),predominantly located within the Jizhong Depression and Cangxian Uplift in the Bohai Bay Basin,serves as the primary region for geothermal exploitation and utilization in China.More than 1500 geothermal wells have been drilled therein,with water temperature at the wellhead ranging from 55 to 110°C,single-well flow rate ranging between 80 and 120 m^(3)/h,and cumulative heating area exceeding 100×10^(6)m^(3).However,the exploration and research in the region remain limited overall.As per the previous geothermal and petroleum exploration results and the latest geothermal drilling data,this study comprehensively evaluated the geothermal resources of karst geothermal reservoirs.The results show that two suites of carbonate karst reservoirs,namely the Jxw Formation and the Ordovician strata,have primarily developed in the BTHP,and their formation and evolution can be divided into four stages:the Mesoproterozoic-Early Paleozoic stage with carbonate sedimentation and the development of interlayer karst,the Late Paleozoic stage with the development of direct sedimentary cover,the Mesozoic stage with compressional uplifting and development of buried hill karst,and the Cenozoic stage with regional cover deposition and the modification and finalization of karst geothermal reservoirs.Accordingly,the porosity evolution history of the geothermal reservoirs is composed of three stages,namely a significant decrease followed by a minor increase,a gradual decline,and then a small fluctuation from increase to decrease before slowly rising again.The karstification in geothermal reservoirs can be summarized into quasi-syngenetic karstification,epigenetic karstification,and burial karstification,which can be subdivided into seven subcategories.The carbonate geothermal reservoirs in the study area boast total geothermal resources of 53.821×10^(9)GJ,or 184.155×10^(9)t of standard coal equivalent(tce),and the annual exploitable geothermal resources in the urban area can heat an area of(400‒500)×10^(6)m^(3),indicating great potential of geothermal exploitation. 展开更多
关键词 Carbonate geothermal reservoir Formation mechanism Karstification type Resource assessment Beijing-Tianjin-Hebei plain(BTHP)
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Gravity-Driven Listric Growth Fault and Sedimentation in the Lagoa do Peixe, Rio Grande do Sul Coastal Plain, Brazil
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作者 Bruno Silva da Fontoura Adelir José Strieder +1 位作者 Iran Carlos Stalliviere Corrêa Paulo Rogério Mendes 《Open Journal of Geology》 CAS 2024年第4期594-616,共23页
High frequency, high resolution GPR surveys are successfully applied to investigate near-surface stratification architecture of sedimentary units in coastal plains and to define their depositional conditions. However,... High frequency, high resolution GPR surveys are successfully applied to investigate near-surface stratification architecture of sedimentary units in coastal plains and to define their depositional conditions. However, low frequency GPR surveys to investigate fault-related depositional systems at greater depths are scarce. This survey was designed investigate a > 100 km long linear escarpment that controls the northwest margin of the Lagoa do Peixe, an important lagoon in Rio Grande do Sul Coastal Plain (RGSCP, Brazil). The traditional approach points that RGSCP was developed by juxtaposition of four lagoons/barrier systems as consequence of sea level changes;no deformational structure is admitted to exist before. The low frequency GPR (50 MHz, RTA antenna) and geological surveys carried out in the RGSCP showed the existence of a large, gravity-driven listric growth fault controlling the Lagoa do Peixe escarpment and hangingwall sedimentation. The radargrams in four subareas along the Lagoa do Peixe Growth Fault could be interpreted following the seismic expression of rift-related depositional systems. The radargrams enabled to distinguish three main lagoonal deposition radarfacies. The lower lagoonal radarfacies is a convex upward unit, thicker close to growth fault;the radarfacies geometry indicates that fault displacement rate surpasses the sedimentation rate, and its upper stratum is aged ~3500 <sup>l4</sup>C years BP. The second lagoonal radarfacies is a triangular wedge restricted to the lagoon depocenter, whose geometry indicates that fault displacement and the sedimentation rates kept pace. The upper lagoonal radarfacies is being deposited since 1060 ± 70 <sup>l4</sup>C years BP, under sedimentation rate higher than fault displacement rate. The results indicate that low frequency GPR surveys can help in investigating fault-related depositional systems in coastal zones. They also point to a new approach in dealing with RGSCP stratigraphy. 展开更多
关键词 GPR (Ground-Penetrating Radar) Growth Fault SEDIMENTATION Radarfacies Coastal plain
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Translation Strategies of Red Tourism Terms in the Central Plains-Taking Red Central Plains as an Example
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作者 YUN Meng-nan 《Journal of Literature and Art Studies》 2024年第2期133-137,共5页
In recent years,the Red Tourism in Central Plains has gradually become a new type of thematic tourism form,which is an important carrier to carry out patriotism and revolutionary traditional education and carry forwar... In recent years,the Red Tourism in Central Plains has gradually become a new type of thematic tourism form,which is an important carrier to carry out patriotism and revolutionary traditional education and carry forward the national spirit.The translation of red tourism publicity is an important window for spreading Chinese culture,and the translation of professional terms is an important link in the red tourism publicity.How to spread the red culture of the Central Plains,glow the charm of the Central Plains culture,enhance the influence of the Central Plains culture,and spread the Central Plains culture to the world has become the mission of every child of the Central Plains.This paper adopts the case analysis method,combined with the specific and typical cases in“Red Central Plains”,and uses different translation strategies and methods to explore the difficulties and solutions of the translation of terms in the red tourism text. 展开更多
关键词 Red tourism Publicity translation Central plains culture translation strategy
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Life Needs More Goals,and Fewer Complaints
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作者 王端鑫 陈传光(指导) 《中学生英语》 2024年第22期8-8,共1页
In my opinion,we should have more goals in our lives and have fewer complaints.As is known to all,goals make us go further and prevent us from being lazy.When we have goals,we are encouraged to work hard to achieve th... In my opinion,we should have more goals in our lives and have fewer complaints.As is known to all,goals make us go further and prevent us from being lazy.When we have goals,we are encouraged to work hard to achieve them.But if we lose our goals,we may feel uncertain and insecure.For a student,goals do play an essential role in study.I once set a goal to play better in basketball games,and I tried my best to train myself without any fear and hesitation.It was the goal that helped me accomplish my ambition. 展开更多
关键词 tried plain goals
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Soil Organic Carbon Stock Variation under Different Soil Types and Land Uses in the Sub-Humid Noun Plain, Western Cameroon
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作者 Frank Abigail Sobze Kenfack Georges Kogge Kome +2 位作者 Achille Bienvenue Ibrahim Viviane Pauline Mandah Dieudonne Bitondo 《Open Journal of Soil Science》 2024年第4期191-209,共19页
This study was conducted to assess the current stock of soil organic carbon under different agricultural land uses, soil types and soil depths in the Noun plain in western Cameroon. Three sites were selected for the s... This study was conducted to assess the current stock of soil organic carbon under different agricultural land uses, soil types and soil depths in the Noun plain in western Cameroon. Three sites were selected for the study, namely Mangoum, Makeka and Fossang, representative of the three dominant soil types of the noun plain (Andosols, Acrisols and Ferralsols). Three land uses were selected per site including natural vegetation, agroforest and crop field. Soil was sampled at three depths;0 - 20 cm, 20 - 40 cm, and 40 - 60 cm. Analysis of variance showed that soil type did not significantly influence carbon storage, but rather land uses and soil depth. SOCS decreased significantly with depth in all the sites, with an average stock of 66.3 ± 15.8 tC/ha at 0 - 20 cm, compared to an average stock of 33.3 ± 7.4 tC/ha at 40 - 60 cm. SOCS was significantly highest in the natural formation with 57.2 ± 19.7 tC/ha, and lowest in cultivated fields, at 37.7 ± 10.6 tC/ha. Andosols, with their high content of coarse fragments, stored less organic carbon than Ferralsols and Acrisols. 展开更多
关键词 Carbon Stocks Soil Type Soil Depth Agricultural Land Use Noun plain
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Analysis of the Groundwater System Change and Driving Factors in Songnen Plain in Jilin Province 被引量:1
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作者 郭晓东 张晶 +2 位作者 田辉 朱威 张梅桂 《Agricultural Science & Technology》 CAS 2011年第5期741-744,共4页
[Objective] The aim was to provide theoretical basis for the study of underground water dynamic changes in Songnen Plain in Jilin Province.[Method] The dynamic changes and driving factors for the underground water in ... [Objective] The aim was to provide theoretical basis for the study of underground water dynamic changes in Songnen Plain in Jilin Province.[Method] The dynamic changes and driving factors for the underground water in Songnen Plain in Jilin Province was expounded.[Result] Since 1960s,the temperature in the Songnen Plain in Jilin Province increased gradually.The average temperature increased 2℃;precipitation reduced gradually.Especially,the trend of precipitation reduction in west area was more distinct;in the meantime,the development of underground water augmented gradually and reached 2 800 million m3 in 2008.Driven by many factors,regional underground water level had distinct changes.Potential water position reduced greatly in northwest fan-shaped area.The one in other places were stable and even increased in certain parts;confined water position decreased quickly in general and it increased in certain parts.[Conclusion] The general deterioration trend of underground water environment was inevitable.But,the deterioration process can be eased through scientific planning and regional underground water resources so as to realize sustainable utilization of regional underground water resources. 展开更多
关键词 Songnen plain Groundwater dynamic Drive factor
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Groundwater Flow Simulation and its Application in Groundwater Resource Evaluation in the North China Plain,China 被引量:10
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作者 SHAO Jingli LI Ling +1 位作者 CUI Yali ZHANG Zhaoji 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第1期243-253,共11页
The purpose of this study is to establish a 3D groundwater flow modelling for evaluating groundwater resources of the North China Plain. First, the North China Plain was divided into three aquifers vertically through ... The purpose of this study is to establish a 3D groundwater flow modelling for evaluating groundwater resources of the North China Plain. First, the North China Plain was divided into three aquifers vertically through a characterization of hydrogeological conditions. Groundwater model software GMS was used for modeling to divide the area of simulation into a regular network of 164 rows and 148 lines. This model was verified through fitting of the observed and the simulated groundwater flow fields at deep and shallow layers and comparison between the observed and simulated hydrographs at 64 typical observation wells. Furthermore, water budget analysis was also performed during the simulation period (2002-2003). Results of the established groundwater flow model showed that the average annual groundwater recharge of the North China Plain during 1991 to 2003 was 256.68x10s m3/yr with safe yield of groundwater resources up to 213.49x10s m3/yr, in which safe yield of shallow groundwater and that of deep groundwater was up to 191.65x10s m3/yr and 22.64x10s m~/yr respectively. Finally, this model was integrated with proposal for groundwater withdrawal in the study area after commencement of water supply by South-North Water Transfer Project, aiming to predict the changing trend of groundwater regime. As indicated by prediction results, South-North Water Transfer Project, which is favorable for effective control of expansion and intensification of existing depression cone, would play a positive role in alleviation of short supply of groundwater in the North China Plain as well as maintenance and protection of groundwater. 展开更多
关键词 GroundWATER model groundwater recharge safe yield South-North Water TransferProject North China plain
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