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Microstructure Characteristics and Possible Phase Evolution of the Coal Gangue-Steel Slag Ceramics Prepared by the Solid-State Reaction Methods
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作者 刘文洁 WANG Yang +1 位作者 LI Jingtao 李宝让 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期921-930,共10页
Industrial wastes such as steel slag and coal gangue etc.were chosen as raw materials for preparing ceramic via the conventional solid-state reaction method.With steel slag and coal gangue mixed in various mass ratios... Industrial wastes such as steel slag and coal gangue etc.were chosen as raw materials for preparing ceramic via the conventional solid-state reaction method.With steel slag and coal gangue mixed in various mass ratios,from 100%steel slag to 100%coal gangue at 10%intervals,microstructure and possible phase evolution of the coal gangue-steel slag ceramics were investigated using X-ray powder diffraction,scanning electron microscopy,mercury intrusion porosimetry and Archimedes boiling method.The experimental results suggest that the phase compositions of the as-prepared ceramics could be altered with the increased amount of coal gangue in the ceramics.The anorthite-diopside eutectic can be formed in the ceramics with the mass ratios of steel slag to coal gangue arranged from 8:2 to 2:8,which was responsible for the melting of the steel slag-coal gangue ceramics at relatively high temperature.Further investigations on the microstructure suggested that the addition of the proper amount of steel slag in ceramic compositions was conducive to the pore formation and further contributed to an increment in porosity. 展开更多
关键词 steel slag-coal gangue ceramics SYNTHESIS phase evolution microstructure characteristics
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Structural Characteristics and Evolution of a Weighted Sino-US Container Shipping Network
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作者 ZHANG Tiantian XI Daping +3 位作者 JIANG Wenping FENG Yuhao WANG Chuyuan HU Xini 《Chinese Geographical Science》 SCIE CSCD 2024年第5期810-828,共19页
This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constru... This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constructs a Sino-US container shipping network through voyage weighting and analyzes the essential structural characteristics to explore the network’s complex structural fea-tures.The network’s evolution is examined from three perspectives,namely,time,space,and event influence,aiming to comprehens-ively explore the network’s evolution mechanism.The results revealed that:1)the weighted Sino-US container shipping network exhib-its small-world and scale-free properties.Key hub ports in the United States include NEW YORK NY,SAVANNAH GA,LOS ANGELES CA,and OAKLAND CA,whereas SHANGHAI serving as the hub port in China.The geographical distribution of these hub ports is uneven.2)Concerning the evolution of the weighted Sino-US container shipping network,from a temporal perspective,the evolution of the regional structure of the entire Sino-US region and the Inland United States is in a stage of radiative expansion and de-velopment,with a need for further enhancement in competitiveness and development speed.The evolution of the regional structure of southern China and Europe is transitioning from the stage of radiative expansion and development to an advanced equilibrium stage.The shipping development in Northern China,the Western and Eastern United States,and Asia is undergoing significant changes but faces challenges of fierce competition and imbalances.From a spatial perspective,the rationality and effectiveness of the improved weighted Barrat-Barthelemy-Vespignani(BBV)model are confirmed through theoretical derivation.The applicability of the improved evolution model is verified by simulating the evolution of the weighted Sino-US container shipping network.From an event impact per-spective,the Corona Virus Disease 2019(COVID-19)pandemic has not fundamentally affected the spatial pattern of the weighted Sino-US container shipping network but has significantly impacted the network’s connectivity.The network lacks sufficient resilience and stability in emergency situations.3)Based on the analysis of the structural characteristics and evolution of the weighted Sino-US con-tainer shipping network,recommendations for network development are proposed from three aspects:emphasizing the development of hub ports,focusing on the balanced development of the network,and optimizing the layout of Chinese ports. 展开更多
关键词 container shipping network structure characteristics network evolution voyage weighting improved Barrat-Barthelemy-Vespignani(BBV)model
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Evolution and Characteristics of "Carbon Neutrality Movies"
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作者 Licheng LIU Di ZHANG 《Meteorological and Environmental Research》 2024年第3期45-48,共4页
"Carbon neutrality movies"are movies that focus on carbon neutrality as the object of expression and dissemination.Using carbon neutrality as an element,it influences the development of the plot,reflects env... "Carbon neutrality movies"are movies that focus on carbon neutrality as the object of expression and dissemination.Using carbon neutrality as an element,it influences the development of the plot,reflects environmental changes,and focuses on climate change caused by carbon emissions.At the same time,it focuses on offsetting carbon emissions through carbon neutrality behavior,showcasing the impact of carbon neutrality.From the perspective of ecological movies,the evolution of carbon neutrality movies at three stages can be explored.The first stage is high-carbon movies that reflect the high conflict between humans and the natural environment.The second stage is low-carbon movies,reflecting humanity's pursuit of a harmonious coexistence between humans and nature,thus adopting green and low-carbon behaviors.The third stage is carbon neutrality movies,which awaken or guide the public to pay attention to carbon emissions,promote low-carbon living,guide life practice in a carbon neutrality way,and create a better life.There are three characteristics of"carbon neutrality movies",including scientific reflection on global warming,advocating energy conservation and emission reduction in daily life,and promoting clean energy in policies. 展开更多
关键词 Carbon neutrality MOVIE evolution characteristIC
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Characteristic stress variation and microcrack evolution of granite subjected to uniaxial compression using acoustic emission methods
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作者 Yunge Zhao Xibing Li +2 位作者 Linqi Huang Zhichao Zhang Zihou Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3511-3523,共13页
The size of mineral grain has a significant impact on the initiation and propagation of microcracks within rocks.In this study,fine-,medium-,and coarse-grained granites were used to investigate microcrack evolution an... The size of mineral grain has a significant impact on the initiation and propagation of microcracks within rocks.In this study,fine-,medium-,and coarse-grained granites were used to investigate microcrack evolution and characteristic stress under uniaxial compression using the acoustic emission(AE),digital image correlation(DIC),and nuclear magnetic resonance(NMR)measurements.The experimental results show that the characteristic stress of each granite decreased considerably with increasing grain sizes.The inflection points of the b-value occurred earlier with an increase in grain sizes,indicating that the larger grains promote the generation and propagation of microcracks.The distribution characteristics of the average frequency(AF)and the ratio of rise time to amplitude(RA)indicate that the proportion of shear microcracks increases with increasing grain size.The NMR results indicate that the porosity and the proportion of large pores increased with increasing grain size,which may intensify the microcrack evolution.Moreover,analysis of the DIC and AE event rates suggests that the high-displacement regions could serve as a criterion for the degree of microcrack propagation.The study found that granites with larger grains had a higher proportion of high-displacement regions,which can lead to larger-scale cracking or even spalling.These findings are not only beneficial to understand the pattern of microcrack evolution with different grain sizes,but also provide guidance for rock monitoring and instability assessment. 展开更多
关键词 Grain size Acoustic emission(AE) characteristic stress Microcrack evolution Fracture mode
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Failure characteristics and the damage evolution of a composite bearing structure in pillar-side cemented paste backfilling 被引量:2
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作者 Boqiang Cui Guorui Feng +6 位作者 Jinwen Bai Gaili Xue Kai Wang Xudong Shi Shanyong Wang Zehua Wang Jun Guo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第8期1524-1537,共14页
A backfilling body-coal pillar-backfilling body(BPB)structure formed by pillar-side cemented paste backfilling can bear overburden stress and ensure safe mining.However,the failure response of BPB composite samples mu... A backfilling body-coal pillar-backfilling body(BPB)structure formed by pillar-side cemented paste backfilling can bear overburden stress and ensure safe mining.However,the failure response of BPB composite samples must be investigated.This paper examines the deformation characteristics and damage evolution of six types of BPB composite samples using a digital speckle correlation method under uniaxial compression conditions.A new damage evolution equation was established on the basis of the input strain energy and dissipated strain energy at the peak stress.The prevention and control mechanisms of the backfilling body on the coal pillar instability were discussed.The results show that the deformation localization and macroscopic cracks of the BPB composite samples first appeared at the coal-backfilling interface,and then expanded to the backfilling elements,ultimately appearing in the coal elements.The elastic strain energy in the BPB composite samples reached a maximum at the peak stress,whereas the dissipated energy continued to accumulate and increase.The damage evolution curve and equation agree well with the test results,providing further understanding of instability prevention and the control mechanisms of the BPB composite samples.The restraining effect on the coal pillar was gradually reduced with decreasing backfilling body element's volume ratio,and the BPB composite structure became more vulnerable to failure.This research is expected to guide the design,stability monitoring,instability prevention,and control of BPB structures in pillar-side cemented paste backfilling mining. 展开更多
关键词 backfilling body-coal pillar-backfilling body composite structure digital speckle correlation method uniaxial compression deformation characteristics damage evolution
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Tectonic evolution and accumulation characteristics of Carboniferous shale gas in Yadu-Ziyun-Luodian aulacogen, Guizhou Province, South China 被引量:2
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作者 Kun Yuan Wen-hui Huang +5 位作者 Ting Wang Shi-zhen Li Xiang-can Sun Xin-xin Fang Jun-ping Xiao Jun Guo 《China Geology》 CAS CSCD 2023年第4期646-659,共14页
The Yadu-Ziyun-Luodian aulacogen(YZLA) developed into being NW-trending in the Late Paleozoic,and was considered as an important passive continental margin aulacogen in Guizhou Province, South China. This tectonic zon... The Yadu-Ziyun-Luodian aulacogen(YZLA) developed into being NW-trending in the Late Paleozoic,and was considered as an important passive continental margin aulacogen in Guizhou Province, South China. This tectonic zone is considered a large intracontinental thrust-slip tectonic unit, which has undergone a long period of development. It was ultimately determined in the Yanshanian, where the typical Upper Paleozoic marine shales were deposited. In 2021, Well QSD-1 was deployed in the Liupanshui area at the northwest margin of the aulacogen, and obtained a daily shale gas flow of 11011 m3in the Carboniferous Dawuba Formation. It thus achieved a breakthrough in the invesgation of shale gas in the Lower Carboniferous in South China, revealing relatively good gas-bearing properties and broad exploration prospects of the aulacogen. Being different from the Lower Paleozoic strata in the Sichuan Basin and the Yichang area of the Middle Yangtze, the development of the Carboniferous Dawuba Formation in the aulacogen exhibits the following characteristics:(1) The Lower Carboniferous shale is thick and widely distributed, with interbedded shale and marlstone of virous thickness;(2) The total organic carbon(TOC) content of the shale in the Dawuba Formation ranges from 1% to 5%, with an average of 2%, and the thermal maturity of organic matter(Ro) varies from 1% to 4%, with an average of2.5%, indicating good hydrocarbon generation capacity;(3) The main shale in the aulacogen was formed during the fault subsidence stage from the Middle Devonian to the Early Permian. Although the strong compression and deformation during the late Indosinian-Himalayan played a certain role in destroying the formed shale gas reservoirs, comparative analysis suggests that the area covered by the current Triassic strata has a low degree of destruction. It therefore provides good conditions for shale gas preservation,which can be regarded as a favorable area for the next exploration. 展开更多
关键词 Shale gas AULACOGEN CARBONIFEROUS Shale and marlstone Organic carbon Organic matter Hydrocarbon generation capacity Tectonic evolution Accumulation characteristics
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Research on the Evolution of Media Practices of Leading Cadres’ New Media and the Communication Characteristics
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作者 Hebin Zhang Muhammad Zaffwan Idris 《Social Networking》 2023年第3期57-66,共13页
Purpose/Significance: This study aims to define the concept of leading cadres new media usage in China specifically, and to describe and analyze the forms and typical cases and characteristics of leading cadres new me... Purpose/Significance: This study aims to define the concept of leading cadres new media usage in China specifically, and to describe and analyze the forms and typical cases and characteristics of leading cadres new media in different stages. Method/Process: Based on the themes and contents of a few media accounts of leading cadres at different ranks, we summarizes leading cadres new media usage in a systematic perspective and content analysize method. Result/Conclusion: The study defines the concept of Leading Cadres’ new media from the perspective of media practice, determine its position as a media communication platform in the government affairs new media communication system and its relationship with the other elements, and then systematically review the evolution of its media practice from personal website, blog, microblog and microblog to WeChat, live show. On this basis, with the Harold Lasswell communication model, this article summarizes leading cadres new media communication characteristics from five aspects: content producer, content, channel, audience, and effect. Future studies may also enhance the empirical research from the effect perspective. 展开更多
关键词 Leading Cadres’ New Media evolution of Media Practices Communication characteristics
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Influence of rapid solidification on Sn-8Zn-3Bi alloy characteristics and microstructural evolution of solder/Cu joints during elevated temperature aging 被引量:2
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作者 赵国际 文光华 盛光敏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期234-240,共7页
The effects of rapid solidification on the microstructure and melting behavior of the Sn-8Zn-3Bi alloy were studied. The evolution of the microstructuraI characteristics of the solder/Cu joint after an isothermal agin... The effects of rapid solidification on the microstructure and melting behavior of the Sn-8Zn-3Bi alloy were studied. The evolution of the microstructuraI characteristics of the solder/Cu joint after an isothermal aging at 150 ℃ was also analyzed to evaluate the interconnect reliability. Results showed that the Bi in Sn-8Zn-3Bi solder alloy completely dissolved in the Sn matrix with a dendritic structure after rapid solidification. Compared with as-solidified Sn-8Zn-3Bi solder alloy, the melting temperature of the rapid solidified alloy rose to close to that of the Sn-Zn eutectic alloy due to the extreme dissolution of Bi in Sn matrix. Meanwhile, the adverse effect on melting behavior due to Bi addition was decreased significantly. The interfacial intermetallic compound (IMC) layer of the solder/Cu joint was more compact and uniform. Rapid solidification process obviously depressed the formation and growth of the interfacial IMC during the high-temperature aging and improved the high-temperature stability of the Sn-8Zn-3Bi solder/Cu joint. 展开更多
关键词 rapid solidification Sn-8Zn-3Bi solder melting characteristic AGING microstructural evolution
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Experimental investigation of spectral evolution in flash radiation by hypervelocity impact on aluminum plates
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作者 Xing Chen Yonggang Lu +1 位作者 Zhiwen Li Zhonghua Cui 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期96-110,共15页
In this study,a series of hypervelocity impact tests were carried out based on a two-stage light gas gun,and the sequence spectrum and radiation evolution data of the impact products under different impact conditions ... In this study,a series of hypervelocity impact tests were carried out based on a two-stage light gas gun,and the sequence spectrum and radiation evolution data of the impact products under different impact conditions were obtained.The diameter of the projectile is 3-5 mm,the impact velocity is 3.13-6.58 km/s,and the chamber pressure is 0.56-990 Pa.The spectrum of ejected debris cloud in the 250-310 nm band were obtained using a transient spectral measurement system and a multi-channel radiometer measurement system.The test results reveal that the flash radiation intensity increases as a power function with the kinetic energy of the impact.Furthermore,the peak value of the line spectrum decreases as the chamber vacuum degree increases,while the radiation width gradually expands.The line spectrum in the spectral characterization curve corresponds to the ejected debris clouds splitting phase,which does not produce significant line spectrum during material fragmentation and is dominated by the continuum spectrum produced by blackbody radiation.There will appear one or three characteristic peaks in the flash radiation time curve,the first and second peaks correspond to the penetration phase and the third peak corresponds to the expansion phase of the ejected debris clouds on the time scale,the first and second peaks are more sensitive to the chamber vacuum degree,and when the pressure is higher than 99 Pa,the first and second characteristic peaks will disappear.The radiant heat attenuation of the flash under different impact conditions is significantly different,the attenuation exponent has a power function relationship with the impact velocity and the chamber vacuum degree,while the attenuation exponent has a linear relationship with the diameter of the projectile,the specific expression of the attenuation exponent is obtained by fitting.The findings from this research can serve as a valuable reference for remote diagnostic technologies based on flash radiation characteristics. 展开更多
关键词 Hypervelocity impact Flash radiation evolution Spectral characteristics Damage evaluation
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Micro-macro evolution of mechanical behaviors of thermally damaged rock:A state-of-the-art review
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作者 Yunmin Wang Jun Peng +2 位作者 Linfei Wang Chuanhua Xu Bibo Dai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2833-2853,共21页
The influence of thermal damage on macroscopic and microscopic characteristics of different rocks has received much attention in the field of rock engineering.When the rocks are subjected to thermal treatment,the chan... The influence of thermal damage on macroscopic and microscopic characteristics of different rocks has received much attention in the field of rock engineering.When the rocks are subjected to thermal treatment,the change of macroscopic characteristics and evolution of micro-structure would be induced,ultimately resulting in different degrees of thermal damage in rocks.To better understand the thermal damage mechanism of different rocks and its effect on the rock performance,this study reviews a large number of test results of rock specimens experiencing heating and cooling treatment in the laboratory.Firstly,the variations of macroscopic behaviors,including physical parameters,mechanical parameters,thermal conductivity and permeability,are examined.The variations of mechanical parameters with thermal treatment variables(i.e.temperature or the number of thermal cycles)are divided into four types.Secondly,several measuring methods for microstructure,such as polarizing microscopy,fluorescent method,scanning electron microscopy(SEM),X-ray computerized tomography(CT),acoustic emission(AE)and ultrasonic technique,are introduced.Furthermore,the effect of thermal damage on the mechanical parameters of rocks in response to different thermal treatments,involving temperature magnitude,cooling method and thermal cycle,are discussed.Finally,the limitations and prospects for the research of rock thermal damage are proposed. 展开更多
关键词 Thermal damage Macroscopic characteristics Microstructure evolution Temperature magnitude Cooling method Thermal cycle
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Unstable evolution of railway slope under the rainfall-vibration joint action
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作者 DONG Haoyu WANG Jiading +2 位作者 ZHANG Dengfei LI Lin XU Yuanjun 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1419-1431,共13页
Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains.However,as two major factors affecting the stability of railway slopes,few s... Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains.However,as two major factors affecting the stability of railway slopes,few scholars have explored the unstable evolution of railway slopes under the joint action of rainfall-vibration.Based on the model test of sandy soil slope,the unstable evolution process of slope under locomotive vibration,rainfall,and rainfall-vibration joint action conditions was simulated in this paper.By comparing and analyzing the variation trends of soil pressure and water content of slope under these conditions,the change laws of pore pressure under the influence of vibration and rainfall were explored.The main control factors affecting the stability of slope structure under the joint action conditions were further defined.Combined with the slope failure phenomena under these three conditions,the causes of slope instability resulting from each leading factor were clarified.Finally,according to the above conclusions,the unstable evolution of the slope under the rainfall-vibration joint action was determined.The test results show that the unstable evolution process of sandy soil slope,under the rainfall-vibration joint action,can be divided into:rainfall erosion cracking,vibration promotion penetrating,and slope instability sliding three stages.In the process of slope unstable evolution,rainfall and vibration play the roles of inducing and promoting slide respectively.In addition,the deep cracks,which are the premise for the formation of the sliding surface,and the violent irregular fluctuation of soil pressure,which reflects the near penetration of the sliding surface,constitute the instability characteristics of the railway slope together.This paper reveals the unstable evolution of sandy soil slopes under the joint action of rainfall-vibration,hoping to provide the theoretical basis for the early warning and prevention technology of railway slopes. 展开更多
关键词 Rainfall vibration joint action Small scale model tests Unstable evolution process Unstable characteristics Inducing sliding and promoting sliding
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Characteristics of geological structures in Shiling and Zhuanshanhu areas of Yehe Uplift,NE China
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作者 GUAN Yue YU Yinghua +1 位作者 ZHANG Yaxiong YUAN Hongqi 《Global Geology》 2024年第2期105-120,共16页
The basin marginal fault system is the key to understand the formation and evolution of Songliao Basin.In order to investigate the influence of marginal fault system on the structural evolution of Songliao Basin,a com... The basin marginal fault system is the key to understand the formation and evolution of Songliao Basin.In order to investigate the influence of marginal fault system on the structural evolution of Songliao Basin,a comprehensive study was conducted on Shiling Town and Zhuanshanhu area of Yehe Town in Siping City of Jilin Province,where is the southeastern margin of the Songliao Basin and there are a series of well-exposed fault,fold and intrusive bodies belonging to the main marginal fault system of the Songliao Basin known as the Jiamusi-Yitong(Jia-Yi)fault zone.Through profile measurement and field investigation,samples with various lithologies and distinctive features were collected.Detailed field and laboratory works include component and microstructure analysis of these samples,rock-rock contact analysis,main strike measurement and statistics analysis.These data reveal the structural characteristics of the fold,fault and intrusive bodies in the study area.The research results show that the folds are distributed in the Mesozoic strata near the main fault of the eastern branch of the Jia-Yi fault zone,and the folded strata involve the Cretaceous Denglouku and Quantou formations.In addition,the section is dominated by high-angle strikeslip thrust faults.Light-colored veins and dark-colored veins are extensively distributed in the exposed granites.Statistical analysis of joint and fault attitudes in the study area reveals a right-lateral strike-sliping along the main fault.The large-scale right-lateral strike-slip and thrust fault system in Shiling Town occurred in right-lateral transpressive stage in Late Cretaceous.Based on the results above,tectonic evolution sequence in Shiling section of the Jia-Yi fault zone during the Mesozoic can be divided into five stages:Middle Jurassic left-lateral ductile strike-slip stage,Late Jurassic compression stage,Early Cretaceous tension stage,Early Cretaceous extension stage and Late Cretaceous right-lateral transpressive stage.These may have important constraint on understanding the Mesozoic evolution of the Songliao Basin. 展开更多
关键词 Jia-Yi fault structural characteristics evolution sequence Shiling Zhuanshanhu northern segment Tanlu fault
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The Temporal and Spatial Evolution Characteristics Analysis of Jiangsu Tourism Economy
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作者 张学文 丁正山 《Journal of Landscape Research》 2010年第2期82-86,共5页
[Objective] The paper aimed to reflect the spatial pattern and temporal and spatial evolution characteristics, the differences between inter-regional tourism economy was measured from the quality aspect, which provide... [Objective] The paper aimed to reflect the spatial pattern and temporal and spatial evolution characteristics, the differences between inter-regional tourism economy was measured from the quality aspect, which provided a reference for the local governments in the future tourism development. [Method] Using the location entropy methods, three time periods side of tourism-related date of 2000, 2005, 2007 were selected, from the angle of the spatial pattern and the evolution of the differences within the different scales, the spatial and temporal evolution characteristics of the economic development level of Jiangsu were analysed. [Result] The results showed that from the aspect of spatial evolution pattern, as time goes on, the economic development of Jiangsu tourism has experienced morphological evolution of concentration- dispersion decrease-stability; when it comes to the development of the tourism economy, in recent years, the overall gap between the tourism economy in Jiangsu did not widen, the gap mainly led by the region one after another. According to their volatility, it will be divided into four categories: A Stable type (Wuxi, Xuzhou, Lianyungang and Taizhou), B Increasing type (Huai’an), C Fluctuations type (Nanjing, Changzhou, Suzhou and Yangzhou) and D Depression type (Nantong, Yancheng, Zhenjiang and Suqian). [Conclusion] Location entropy was quoted into tourism economic analysis, the method was simple and easy to understand, the result was accurate and convincing, which provided a reference for travel economic development and investment decision-making of Jiangsu. 展开更多
关键词 Location entropy Tourist economy Temporal and Spatial evolution characteristics Jiangsu
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Deformation and failure characteristics and fracture evolution of cryptocrystalline basalt 被引量:5
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作者 Zhenjiang Liu Chuanqing Zhang +3 位作者 Chunsheng Zhang Yang Gao Hui Zhou Zhaorong Chang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第5期990-1003,共14页
Cryptocrystalline basalt is one of the two major types of rocks exposed in the super large-scale underground powerhouse in Baihetan hydropower station in China.The rock of this type shows various sitespecific mechanic... Cryptocrystalline basalt is one of the two major types of rocks exposed in the super large-scale underground powerhouse in Baihetan hydropower station in China.The rock of this type shows various sitespecific mechanical responses(e.g.fragmentation,fracturing,and relaxation)during excavation.Using conventional triaxial testing facility MTS 815.03,we obtained the stressestrain curves,macroscopic failure characteristics,and strength characteristics of cryptocrystalline basalt.On this basis,evolution of crack initiation and propagation was explored using the finite-discrete element method(FDEM)to understand the failure mechanism of cryptocrystalline basalt.The test results showed that:(1)under different confining stresses,almost all the pre-peak stressestrain curves of cryptocrystalline basalt were linear and the post-peak stresses decreased rapidly;(2)the cryptocrystalline basalt showed a failure mode in a form of fragmentation under low and medium confining stresses while fragmentation-shear coupling failure dominated at high confining stresses;and(3)the initial strength ratio(sci/sf,where sci and sf are the crack initiation strength and peak strength,respectively)ranged from 0.45 to 0.55 and the damage strength ratio(scd/sf,where scd is the crack damage strength)exceeded 0.9.The stressestrain curve characteristics and failure modes of cryptocrystalline basalt could be reflected numerically.For this,FDEM simulation was employed to reveal the characteristics of cryptocrystalline basalt,including high scd/sf values and rapid failure after scd,with respect to the microscopic characteristics of mineral structures.The results showed that the fragmentation characteristics of cryptocrystalline basalt were closely related to the development of tensile cracks in rock samples prior to failure.Moreover,the decrease in degree of fragmentation with increasing confining stress was also correlated with the dominant effect of confining stress on the tensile cracks. 展开更多
关键词 Baihetan HYDROPOWER STATION CRYPTOCRYSTALLINE BASALT Deformation and failure characteristics characteristic strengths CRACK propagation evolution
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Dynamical characteristics of geomorphologic evolution of the basins covered by Pisha-sandstone in the eastern wing of the Ordos Plateau, China 被引量:4
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作者 GU Zhen-kui SHI Chang-xing 《Journal of Mountain Science》 SCIE CSCD 2018年第5期1046-1056,共11页
There are several basins with high sediment yield in the Pisha-sandstone covering area of the east wing of the Ordos Plateau. Due to the lack of targeted research on the dynamical characteristics of geomorphic evoluti... There are several basins with high sediment yield in the Pisha-sandstone covering area of the east wing of the Ordos Plateau. Due to the lack of targeted research on the dynamical characteristics of geomorphic evolution that plays an important role in the sand production, this paper analyzed the tectonic activity intensity and erosion characteristics of the area. The results show that the intensity of tectonic activities in the area is generally moderateweak and shows an unconspicuous increase from north to south. Tectonic activity is manifested mainly in the form of uplift. The uplift rate in the lower reaches of each basin is greater than the erosion rate,which is prominent in the Kuyehe and the Tuweihe rivers. During the uplift of the regional topography,the most serious parts under erosion are generally concentrated in the upstream and midstream of basins. All longitudinal profiles of the basins have a shape close to an exponential function, which indicates that they are in the early stage of erosion evolution. The mechanisms of geomorphologic evolution of these basins have a great similarity. The conservative estimate of historical average erosion rate was less than 182–520 t/(km^2·yr), much less than that of the modern times. The average stream power values are typically distributed between 4 and102 W/m, with the larger being in the Kuyehe and the Tuweihe rivers and the smallest being in the Qinshuihe River. The maximum stream power value appears in the downstream reach, which should be the main reason for the particles being directly injected into the Yellow River. From the perspective of geomorphological evolution, the current soil and water conservation measures can hardly cure the erosion of these basins in the long run. 展开更多
关键词 Dynamic characteristics Geomorphologic evolution ORDOS PLATEAU Tectonicactivity Stream power Geomorphological parameter
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Tectonic Evolution and Geological Characteristics of Hydrocarbon Reservoirs in Marine Mesozoic-Paleozoic Strata in the South Yellow Sea Basin 被引量:12
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作者 YUAN Yong CHEN Jianwen +3 位作者 ZHANG Yuxi LIANG Jie ZHANG Yinguo ZHANG Penghui 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1075-1090,共16页
The South Yellow Sea Basin is the main body of the lower Yangtze area in which marine Mesozoic–Paleozoic strata are widely distributed.The latest geophysical data were used to overcome the limitation of previous poor... The South Yellow Sea Basin is the main body of the lower Yangtze area in which marine Mesozoic–Paleozoic strata are widely distributed.The latest geophysical data were used to overcome the limitation of previous poor-quality deep data.Meanwhile,the geological characteristics of hydrocarbon reservoirs in the marine Mesozoic–Paleozoic strata in the South Yellow Sea Basin were analyzed by comparing the source rocks and the reservoir and utilizing drilling and outcrop data.It is believed that the South Yellow Sea Basin roughly underwent six evolutionary stages:plate spreading,plate convergence,stable platform development,foreland basin development,faulted basin development,and depression basin development.The South Yellow Sea Basin has characteristics of a composite platform-fault depression geological structure,with a half-graben geological structure and with a ‘sandwich structure' in the vertical direction.Four sets of hydrocarbon source rocks developed – the upper Permian Longtan–Dalong formation,the lower Permian Qixia formation,the lower Silurian Gaojiabian formation,and the lower Cambrian Hetang formation/Mufushan formation,giving the South Yellow Sea Basin relatively good hydrocarbon potential.The carbonate is the main reservoir rock type in the South Yellow Sea area,and there are four carbonate reservoir types:porous dolomitic,reef-bank,weathered crust,and fractured.There are reservoir-forming horizons similar to the typical hydrocarbon reservoirs in the Yangtze land area developed in the South Yellow Sea,and there are three sets of complete source-reservoir-cap rock assemblages developed in the marine strata,with very good hydrocarbon potential. 展开更多
关键词 South Yellow Sea Basin tectonic evolution HYDROCARBON geological characteristics marine Mesozoic-Paleozoic strata
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A chromosome-level genome assembly of rugged rose (Rosa rugosa) provides insights into its evolution, ecology, and floral characteristics 被引量:2
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作者 Fei Chen Liyao Su +15 位作者 Shuaiya Hu Jia-Yu Xue Hui Liu Guanhua Liu Yifan Jiang Jianke Du Yushan Qiao Yannan Fan Huan Liu Qi Yang Wenjie Lu Zhu-Qing Shao Jian Zhang Liangsheng Zhang Feng Chen Zong-Ming(Max)Cheng 《Horticulture Research》 SCIE 2021年第1期1939-1951,共13页
Rosa rugosa,commonly known as rugged rose,is a perennial ornamental shrub.It produces beautiful flowers with a mild fragrance and colorful seed pods.Unlike many other cultivated roses,R.rugosa adapts to a wide range o... Rosa rugosa,commonly known as rugged rose,is a perennial ornamental shrub.It produces beautiful flowers with a mild fragrance and colorful seed pods.Unlike many other cultivated roses,R.rugosa adapts to a wide range of habitat types and harsh environmental conditions such as salinity,alkaline,shade,drought,high humidity,and frigid temperatures.Here,we produced and analyzed a high-quality genome sequence for R.rugosa to understand its ecology,floral characteristics and evolution.PacBio HiFi reads were initially used to construct the draft genome of R.rugosa,and then Hi-C sequencing was applied to assemble the contigs into 7 chromosomes.We obtained a 382.6Mb genome encoding 39,704 protein-coding genes.The genome of R.rugosa appears to be conserved with no additional whole-genome duplication after the gamma whole-genome triplication(WGT),which occurred~100 million years ago in the ancestor of core eudicots.Based on a comparative analysis of the high-quality genome assembly of R.rugosa and other high-quality Rosaceae genomes,we found a unique large inverted segment in the Chinese rose R.chinensis and a retroposition in strawberry caused by post-WGT events.We also found that floral development-and stress response signaling-related gene modules were retained after the WGT.Two MADS-box genes involved in floral development and the stress-related transcription factors DREB2A-INTERACTING PROTEIN 2(DRIP2)and PEPTIDE TRANSPORTER 3(PTR3)were found to be positively selected in evolution,which may have contributed to the unique ability of this plant to adapt to harsh environments.In summary,the high-quality genome sequence of R.rugosa provides a map for genetic studies and molecular breeding of this plant and enables comparative genomic studies of Rosa in the near future. 展开更多
关键词 breeding characteristics evolution
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Sediment distribution characteristics and environment evolution within 100 years in western Laizhou Bay,Bohai Sea,China 被引量:4
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作者 Mao-sheng Gao Guo-hua Hou +1 位作者 Xian-zhang Dang Xue-yong Huang 《China Geology》 2020年第3期445-454,共10页
This study is about the reconstruction of fluvial origins based on the grain size distribution of sediment deposits in the western Laizhou Bay,Bohai Sea,China.Thirteen sediment cores were selected to research sediment... This study is about the reconstruction of fluvial origins based on the grain size distribution of sediment deposits in the western Laizhou Bay,Bohai Sea,China.Thirteen sediment cores were selected to research sediment characteristics using the Sahu discriminant formula,C-M diagram,and Folk method.The results showed:(1)Bounded by the Guangli River estuary,the north sediment was affected by the water and sand flowing from the Yellow River during different periods.The south sediment came from multi-source rivers under the influence of the Xiaoqing River,Mihe River,and other coastal rivers;(2)the deposited sediments were dated by a clear historical record of the branched channel oscillation combined with the characteristics of the diversion channel,erosion,and regression.The subaqueous delta overlapped during several Yellow River channel runs(1897–1904,1929–1934,1938–1947,1947–1953,1976–1996)and the deposited sediment facies changed(the north tidal flat-abandoned subaqueous delta-lateral delta-delta front);(3)the deposited sediment characteristics can be revealed by studying the branched diversions of the Yellow River and coastal multi-rivers of the past one hundred years. 展开更多
关键词 SEDIMENT Grain size SILT Environment evolution Distribution characteristic Hydrogeological engineering Laizhou Bay Qingdao City China
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A Contrastive Appraisal Study on Modern Evolution of Female's Non-prototype Characteristics——A Case Study of Different Wu Zetian's Biographical Versions
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作者 俞琳 杨建梅 《海外英语》 2012年第21期191-193,共3页
Within the framework of Appraisal theory,this thesis attempts to do the discourse analysis of modern evolution of fe males'non-prototype characteristics through six versions of biographies of Wu Zetian(included Li... Within the framework of Appraisal theory,this thesis attempts to do the discourse analysis of modern evolution of fe males'non-prototype characteristics through six versions of biographies of Wu Zetian(included Lin Yutang's Lady Wu,and Yuan Baidai's Wu Zetian) in modern times,which aims to uncover the implicit relationship of language and ideology of these different Wu Zetian's biographical versions composed by different authors with different genders and nationalities,which can evoke the readers resonance and affection towards them and reflect the interpersonal function between them by means of excavat ing the regularity of Attitude,Engagement and Graduation resources distribution. 展开更多
关键词 Non-prototype characteristics modern evolution app
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Structural Characteristics and Evolution of Jurassic Basins in the East of Middle Qilian Block 被引量:1
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作者 郑孟林 李明杰 +2 位作者 曹春潮 张勇军 徐世陆 《Journal of China University of Mining and Technology》 2003年第1期35-39,共5页
Structural characteristics of the Jurassic basins of Xining, Minhe, and Xiji in the east of middle Qilian were researched based on the data obtained by gravitational, magnetic, and seismic methods. The result shows th... Structural characteristics of the Jurassic basins of Xining, Minhe, and Xiji in the east of middle Qilian were researched based on the data obtained by gravitational, magnetic, and seismic methods. The result shows that each of these three basins is an independent structural unit with a NW strike and being separated by upheavals. Two groups of faults with NW and NE directions are developed in the basin, which controls the formation and evolution of the (Jurassic basins). The NW faults are the main ones while the NE faults are the secondary for controlling the sedimentation. Of the three basins, the Minhe basin is the favorable prospecting area. 展开更多
关键词 east of middle Qilian Jurassic basin structural characteristic evolution prospecting of oil and gas
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