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Analysis of Division of Beibei Agro-climatic Zones
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作者 汪志辉 马君 +1 位作者 吉莉 刘斌 《Agricultural Science & Technology》 CAS 2013年第6期870-874,898,共6页
[Objective] The aim was to analyze and explore division of agro-climatic zones of Beibei District in Chongqing municipality. [Method] According to major triple-cropping crops in Beibei District, such as wheat (spring... [Objective] The aim was to analyze and explore division of agro-climatic zones of Beibei District in Chongqing municipality. [Method] According to major triple-cropping crops in Beibei District, such as wheat (spring and winter), rice (midmaturation early season rice, later-maturation early rice, later-maturation late rice and middle-season rice), heat demanded by rapeseed, different cultivation methods and cultivation regions with different crop varieties, the accumulated temperatures in four cultivation regions featured by special cultivation methods and variety-matching are concluded. Based on average and accumulated temperatures in different locations in 30 y and other factors, such as terrain, elevation, rainfall and soil property, Beibei District can be classified into four agro-climatic zones. [Result] Four cultivation regions are as follows: the 1st cultivation region where accumulated temperature in T y is ≥6 530 ℃, the 2nd cultivation region where 6 530 ℃ accumulated temperature in T y≥6 350 ℃, the 3rd cultivation region where 6 530 ℃ accumulated temperature in T y≥5 990 ℃, and the 4th cultivation region where accumulated temperature in T y is ≤5 990 ℃. Beibei District can be classified into four agro-climatic zones, involving lower hill temperate zone, higher hill temperate zone, single-slope lower hills and karst temperate zone, and lower ridge cool zone. [Conclusion] Based on characters of four agro-climatic zones and accumulated temperatures required in four cultivation regions, agro-climatic zones can be classified in Beibei District, providing references for rational arrangement of crops and is of significance for stabilization of agricultural production, improvement of crops and increase of farmers’ income. 展开更多
关键词 Accumulated temperature Farming area agro-climatic zones
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Assessing the Impacts of Climate Change on Crop Yields in Different Agro-climatic Zones of India
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作者 Naveen P Singh Bhawna Anand +3 位作者 S K Srivastava K V Rao S K Bal M Prabhakar 《Journal of Atmospheric Science Research》 2020年第4期16-27,共12页
The study attempts to estimate and predict climate impact on crop yields using future temperature projections under two climate emissions scenarios of RCP 4.5 and 8.5 for three different time periods(2030s,2050s and 2... The study attempts to estimate and predict climate impact on crop yields using future temperature projections under two climate emissions scenarios of RCP 4.5 and 8.5 for three different time periods(2030s,2050s and 2080s)across Agro-climatic zones(ACZ)of India.During the period 1966-2011,a significant rise was observed in both the annual mean maximum and minimum temperature across ACZs.Rainfall recorded an annual decline in Himalayan Regions and Gangetic Plains and a rise in Coastal Regions,Plateau&Hills and Western Dry Region.Our results showed high heterogeneity in climate impact on kharif and rabi crop yields(with both negative and positive estimates)across ACZs.It was found that rainfall had a positive effect on most of crop yields,but was not sufficient enough to counterbalance the impact of temperature.Changes in crop yield were more pronounced for higher emission scenario of RCP 8.5.Thus,it was evident that the relative impacts of climate change and the associated vulnerability vary by ACZs,hence comprehensive crop and region-specific adaptation measures should be emphasized that helps in enhancing resilience of agricultural system in short to medium term. 展开更多
关键词 agro-climatic zones Climate change Crop yields RCPs
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Deformation mechanism and NPR anchor cable truss coupling support in tunnel through fault fracture zone
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作者 HUO Shusen TAO Zhigang +2 位作者 HE Manchao WANG Fengnian XU Chuang 《Journal of Mountain Science》 2025年第1期354-374,共21页
To address the issue of extensive deformation in the Tabaiyi Tunnel caused by the fault zone,nuclear magnetic resonance(NMR)technology was employed to analyze the physical and mechanical properties of waterabsorbing m... To address the issue of extensive deformation in the Tabaiyi Tunnel caused by the fault zone,nuclear magnetic resonance(NMR)technology was employed to analyze the physical and mechanical properties of waterabsorbing mudstone.This analysis aimed to understand the mechanism behind the significant deformations.Drawing from the principle of excavation stress compensation,a support scheme featuring NPR anchorcables and an asymmetric truss support system was devised.To validate the scheme,numerical analysis using a combination of the Discrete Element Method(DEM)-Finite Element Method(FEM)was conducted.Additionally,similar material model tests and engineering measurements were carried out.Field experiments were also performed to evaluate the NPR anchor-cable and truss support system,focusing on anchor cable forces,pressures between the truss and surrounding rock,pressures between the initial support and secondary lining,as well as the magnitude of settlement and convergence deformation in the surrounding rock.The results indicate that the waterinduced expansion of clay minerals,resulting from damage caused by fissure water,accelerated the softening of the mudstone's internal structure,leading to significant deformations in the Tabaiyi Tunnel under high tectonic stress.The original support design fell short as the length of the anchor rods was smaller than the expansion depth of the plastic zone.As a result,the initial support structure bore the entire load from the surrounding rock,and a non-coupled deformation contact was observed between the double-arch truss and the surrounding rock.The adoption of NPR asymmetric anchor-cable support effectively restrained the expansion and asymmetric distribution characteristics of the plastic zone.Considering the mechanical degradation caused by water absorption in mudstone,the rigid constraint provided by the truss proved crucial for controlling the stability of the surrounding rock.These research findings hold significant implications for managing large deformations in soft rock tunnels situated within fractured zones under high tectonic stress conditions. 展开更多
关键词 Fault fracture zone Large deformation Nuclear magnetic resonance NPR anchor cable truss support Coupled simulation
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Agro-climatic Resource Zoning in Jiangsu Province 被引量:1
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作者 买苗 査书评 +1 位作者 朱宝 许玲 《Meteorological and Environmental Research》 CAS 2010年第11期59-63,共5页
The climatic resource model in Jiangsu Province is established by using multivariate regression from meteorological data set during 1970 to 2008 provided by 70 meteorological stations.By dint of GIS and spatial model ... The climatic resource model in Jiangsu Province is established by using multivariate regression from meteorological data set during 1970 to 2008 provided by 70 meteorological stations.By dint of GIS and spatial model of climate resources,the climate resource diagram of Jiangsu Province is designed.Considering the zoning index,the climate resources diagram is superposed and analyzed and thus,the climate resources zoning map generates.Besides,advices are proposed for the direction of agricultural development. 展开更多
关键词 agro-climatic resource agro-climatic zoning GIS China
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The Utilizing of Agro-climatic Resources and Preventing Measures of Meteorological Disasters in Fushun 被引量:3
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作者 GAO Shang-wen1,LI Jin-yi2,LI Tao3,ZHANG Ying4,CHI Gui-fu5 1.Meteorological Bureau of Huanren Manchu Autonomy County of Liaoning Province,Huanren 117200,China 2.Liaoning Meteorological Bureau,Shenyang 110001,China +2 位作者 3.Liaoning Lightening Protection Technology Service Center,Shenyang 110015,China 4.Liaoning Meteorological Schoo,Shenyang 110015,China 5.Fushun Meteorological Bureau,Fushun 113006,China 《Meteorological and Environmental Research》 CAS 2011年第3期61-64,共4页
Based on the meteorological data in Fushun,Qingyuan and Xinbing from 1961 to 2008,the status quo of major agro-climatic resources in Fushun were analyzed.The abundant rainfall,sufficient sunshine and rich thermal reso... Based on the meteorological data in Fushun,Qingyuan and Xinbing from 1961 to 2008,the status quo of major agro-climatic resources in Fushun were analyzed.The abundant rainfall,sufficient sunshine and rich thermal resources were suitable for the development of modern agricultural production.The specific measures of effective use of climate resources were put forward according to geographical location and climatic characteristics of Fushun.The advantages of agro-climate resources were exerted for large edible fungi industry;effective accumulated temperature was applied for adjustment of plantation structure;three-dimensional agriculture in the mountainous area was developed vigorously.The main types of meteorological disasters constraining agricultural development in Fushun and their hazards were summarized,including droughts,floods,hail,etc.In addition,some scientific preventing measures of meteorological disaster were proposed. 展开更多
关键词 agro-climatic resources Meteorological disasters Preventing measures Fushun China
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Agro-climatic Division of Rana chensinensis in Fushun
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作者 LI Liang ZHANG 《Asian Agricultural Research》 2012年第6期77-79,共3页
Based on data collected by 3 basic weather stations in Fushun City and 47 automatic weather stations in the whole region,we selected indexes suitable for agro-climatic division of Rana chensinensis,and carried out a s... Based on data collected by 3 basic weather stations in Fushun City and 47 automatic weather stations in the whole region,we selected indexes suitable for agro-climatic division of Rana chensinensis,and carried out a study on agro-climatic division of Rana chensinensis in this region.Annual active accumulated temperature ≥10 ℃ and precipitation during April and September are used as basic calculation factors,and we use climatic aridity to make climatic division of Rana chensinensis in Fushun City.According to relevant indexes,we divide Fushun City into 3 regions,namely most appropriate,appropriate and general regions.Finally,countermeasures and suggestions are put forward for providing reference for agricultural production. 展开更多
关键词 Fushun Rana chensinensis agro-climatic division
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Prevalence of Muscardine Disease in Different Silkworm Hybrid, Bombyx Mori L. under Agro-climatic Conditions in Aurangabad (M.S.), India
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作者 Bhalerao Rajendra S Hiware Chandrashekhar J Avhad Sunil B 《Journal of Life Sciences》 2011年第2期136-138,共3页
A study was carried out in Dr. Babasaheb Ambedkar Marathwada University Campus Aurangabad, Maharashtra State, India for analyzing the prevalence of Muscardine disease during rainy, winter and summer season in bivoltin... A study was carried out in Dr. Babasaheb Ambedkar Marathwada University Campus Aurangabad, Maharashtra State, India for analyzing the prevalence of Muscardine disease during rainy, winter and summer season in bivoltine x bivoltine hybrids viz. CSR2 × CSR4, CSR4 × CSR2 and multi × bivoltine hybrid PM × CSR2. Observation on Muscardine disease was recorded till the onset of spinning. Analysis of results shows that disease prevalence was more in bivoltine x bivoltine hybrids compare to multi × bivoltine hybrids. PM × CSR2 was found to be more resistant towards Muscardine disease compared to other hybrids under agro-climatic conditions of Aurangabad. 展开更多
关键词 DISEASES muscardine SILKWORM Bombyx mori aurangabad agro-climatic conditions
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Early Triassic Volcanic Rocks in the Western Yarlung Zangbo Suture Zone:Implications for the Opening of the Neo-Tethys Ocean 被引量:1
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作者 HE Juan LI Yalin +4 位作者 HOU Yunling ZHOU Aorigele WEI Yushuai CHEN Xi DAI Jingen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期324-336,共13页
In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-... In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-NdPb isotopic data,the Early Triassic samples could be divided into two groups:Group 1 with P-MORB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70253–0.70602,ε_(Nd)(t)values of 4.2–5.3,(^(206)Pb/^(204)Pb)_(t)ratios of 16.353–18.222,(^(207)Pb/^(204)Pb)_(t)ratios of 15.454–15.564,and(^(208)Pb/^(204)Pb)_(t)ratios of 35.665–38.136;Group 2 with OIB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70249–0.70513,ε_(Nd)(t)values of 4.4–4.9,(^(206)Pb/^(204)Pb)_(t)ratios of 17.140–18.328,(^(207)Pb/^(204)Pb)_(t)ratios of 15.491–15.575,and(^(208)Pb/^(204)Pb)_(t)ratios of 36.051–38.247.Group 2 rocks formed by partial melting of the mantle source enriched by a former plume,and assimilated continental crustal material during melt ascension.The formation of Group 1 rocks corresponds to the mixing of OIB melts,with the same components as Group 2 and N-MORBs.The Zhongba Early Triassic rocks belong to the continental margin type ophiolite and formed in the continental–oceanic transition zone during the initial opening of the Neo-Tethys in southern Xizang(Tibet). 展开更多
关键词 RIFT Early Triassic magmatism Yarlung Zangbo Suture zone NEO-TETHYS Southern Xizang TIBET
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Improving creep strength of the fine-grained heat-affected zone of novel 9Cr martensitic heat-resistant steel via modified thermo-mechanical treatment 被引量:1
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作者 Jingwen Zhang Liming Yu +6 位作者 Yongchang Liu Ran Ding Chenxi Liu Zongqing Ma Huijun Li Qiuzhi Gao Hui Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1037-1047,共11页
The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional the... The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional thermo-mechanical treatment was modified via the replacement of hot-rolling with cold rolling,i.e.,normalizing,cold rolling,and tempering (NCT),which was developed to improve the creep strength of the FGHAZ in G115 steel weldments.The NCT treatment effectively promoted the dissolution of preformed M_(23)C_(6)particles and relieved the boundary segregation of C and Cr during welding thermal cycling,which accelerated the dispersed reprecipitation of M_(23)C_(6) particles within the fresh reaustenitized grains during post-weld heat treatment.In addition,the precipitation of Cu-rich phases and MX particles was promoted evidently due to the deformation-induced dislocations.As a result,the interacting actions between precipitates,dislocations,and boundaries during creep were reinforced considerably.Following this strategy,the creep rupture life of the FGHAZ in G115 steel weldments can be prolonged by 18.6%,which can further push the application of G115 steel in USC power plants. 展开更多
关键词 G115 steel fine-grained heat-affected zone creep strength element segregation nano-sized precipitates
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Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances 被引量:1
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作者 ZHOU Li WANG Guo-rong WAN Min 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期271-284,共14页
An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control... An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller. 展开更多
关键词 adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control
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One-year results for myopia control of orthokeratology with different back optic zone diameters: a randomized trial using a novel multispectral-based topographer 被引量:1
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作者 Wen-Ting Tang Xiang-Ning Luo +4 位作者 Wen-Jing Zhao Jia Liao Xin-Yue Xu Hui-Dan Zhang Li Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期324-330,共7页
AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in ... AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in children.METHODS:This randomized clinical study was performed between Dec.2020 and Dec.2021.Participants were randomly assigned to three groups wearing ortho-k:5 mm BOZD(5-MM group),5.5 mm BOZD(5.5-MM group),and 6 mm BOZD(6-MM group).The 1-year data were recorded,including axial length,relative peripheral refraction(RPR,measured by multispectral refractive topography,MRT),and visual quality.The contrast sensitivity(CS)was evaluated by CSV-1000 instrument with spatial frequencies of 3,6,12,and 18 cycles/degree(c/d);the corneal higher-order aberrations(HOAs)were measured by iTrace aberration analyzer.The one-way ANOVA was performed to assess the differences between the three groups.The correlation between the change in AL and RPR was calculated by Pearson’s correlation coefficient.RESULTS:The 1-year results of 20,21,and 21 subjects in the 5-MM,5.5-MM,and 6-MM groups,respectively,were presented.There were no statistical differences in baseline age,sex,or ocular parameters between the three groups(all P>0.05).At the 1-year visit,the 5-MM group had lower axial elongation than the 6-MM group(0.07±0.09 vs 0.18±0.11 mm,P=0.001).The 5-MM group had more myopic total RPR(TRPR,P=0.014),with RPR in the 15°–30°(RPR 15–30,P=0.015),30°–45°(RPR 30–45,P=0.011),temporal(RPR-T,P=0.008),and nasal area(RPR-N,P<0.001)than the 6-MM group.RPR 15–30 in the 5.5-MM group was more myopic than that in the 6-MM group(P=0.002),and RPR-N in the 5-MM group was more myopic than that in the 5.5-MM group(P<0.001).There were positive correlations between the axial elongation and the change in TRPR(r=0.756,P<0.001),RPR 15–30(r=0.364,P=0.004),RPR 30–45(r=0.306,P=0.016),and RPR-N(r=0.253,P=0.047).The CS decreased at 3 c/d(P<0.001),and the corneal HOAs increased in the 5-MM group(P=0.030).CONCLUSION:Ortho-k with 5 mm BOZD can control myopia progression more effectively.The mechanism may be associated with greater myopic shifts in RPR. 展开更多
关键词 relative peripheral refraction ORTHOKERATOLOGY MYOPIA back optic zone diameter axial length multispectral refractive topography
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Agro-Climatic Risks Analysis in Climate Variability Context in Ségou Region
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作者 Diop Amadou Barro Diakarya 《Open Journal of Statistics》 2023年第1期170-193,共24页
In the Sahel region, the population depends largely on rain-fed agriculture. In West Africa in particular, climate models turn out to be unable to capture some basic features of present-day climate variability. This s... In the Sahel region, the population depends largely on rain-fed agriculture. In West Africa in particular, climate models turn out to be unable to capture some basic features of present-day climate variability. This study proposes a contribution to the analysis of the evolution of agro-climatic risks in the context of climate variability. Some statistical tests are used on the main variables of the rainy season to determine the trends and the variabilities described by the data series. Thus, the paper provides a statistical modeling of the different agro-climatic risks while the seasonal variability of agro-climatic parameters was analyzed as well as their inter annual variability. The study identifies the probability distributions of agroclimatic risks and the characterization of the rainy season was clarified. 展开更多
关键词 Climate Variability agro-climatic Risks Seasonal Evolution Variability Parameters Tests
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Determining the surface fault-rupture hazard zone for the Pazarcık segment of the East Anatolian fault zone through comprehensive analysis of surface rupture from the February 6,2023,Earthquake(Mw 7.7) 被引量:1
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作者 Mustafa SOFTA 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2646-2663,共18页
Following surface rupture observations in populated areas affected by the KahramanmaraşEarthquake(Mw 7.7)on February 6th,2023,along the Pazarcık segment of the East Anatolian Fault Zone(EAFZ),this study presents novel... Following surface rupture observations in populated areas affected by the KahramanmaraşEarthquake(Mw 7.7)on February 6th,2023,along the Pazarcık segment of the East Anatolian Fault Zone(EAFZ),this study presents novel insights into physical criteria for delineating surface fault-rupture hazard zones(SRHZs)along ruptured strike-slip faults.To achieve this objective,three trench studies across the surface rupture were conducted on the Pazarcık segment of the EAFZ to collect field data,and earthquake recurrence intervals were interpreted using Bayesian statistics from previously conducted paleoseismological trenchings.The results of the proposed model indicate that the Pazarcık segment produced five significant surface-rupturing earthquakes in the last∼11 kyr:E1:11.13±1.74 kyr,E2:7.62±1.20 kyr,E3:5.34±1.05 kyr,E4:1.82±0.93 kyr,and E5:0.35±0.11 kyr.In addition,the recurrence intervals of destructive earthquakes on the subject in question range from 0.6 kyr to 4.8 kyr.Considering that the last significant earthquake occurred in 1513,the longest time since the most recent surface fault rupturing earthquake on this particular segment was 511 years.These results indicate that,in terms of the theoretical recurrence interval of earthquakes that can create surface ruptures on the Pazarcık segment,the period in which the February 6,2023,earthquake occurred was within the end of the expected return period.As a result,the potential for a devastating earthquake in the near future is not foreseen on the same fault.Finally,the SRHZ proposed for the Pazarcık section of Gölbaşıvillage was calculated as a 61-meter-wide offset on the fault lineament to reduce the negativities that may occur in the ruptured area in the future.It is recommended to take into account this width in the settlement of this area and nearby areas. 展开更多
关键词 Surface rupture Earthquake mitigation Recurrence interval Pazarcık segment East Anatolian Fault zone(EAFZ)
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The Influence of the Closure of the East Paleo-Tethys Ocean on Southern South China:Evidences from Kinematics and^(40)Ar/^(39)Ar Geochronology of the Rongxian Ductile Shear Zone in Southeastern Guangxi 被引量:1
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作者 HUANG Wenqiang LI Saisai +5 位作者 XIN Liangwei FENG Zuohai ZHANG Hongrui GENG Jieli LIU Kun SHI Chunyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1125-1140,共16页
The Triassic was a crucial period in the tectonic evolution of the South China Block.Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China.In t... The Triassic was a crucial period in the tectonic evolution of the South China Block.Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China.In this study,alongside thermochronological analyses,we examine the macroscopic and microscopic structural features of the Rongxian ductile shear zone,located south of the Darongshan granite in the southeastern part of Guangxi Province,on the southern margin of South China.Sinistral shear is indicated by the characteristics of rotatedσ-type feldspar porphyroclasts,stretching lineations defined by elongated quartz grains and the orientations of quartz c-axes.LA-ICP-MS U-Pb dating of zircons from two samples of granitic mylonite and one of granite yielded ages of ca.256 Ma.Furthermore,two samples of granitic mylonite yield muscovite^(40)Ar/^(39)Ar plateau ages of 249-246 Ma.These results indicate that the Rongxian ductile shear zone resulted from Early Triassic deformation of the late Permian Darongshan granite.This deformation was likely related to the closure of the eastern Paleo-Tethys Ocean and the subsequent collision of the South China and Indochina blocks,during the early stage of the Indosinian orogeny. 展开更多
关键词 ductile shear zone ^(40)Ar/^(39)Ar geochronology TRIASSIC South China Block East Paleo-Tethys Ocean
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Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs 被引量:1
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作者 Lei Yang Baixi Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2960-2981,共22页
In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hy... In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hydraulic fractures in layered porous reservoirs with modulus contrast.The coupled hydromechanical model is first verified against an analytical solution and a laboratory experiment.Then,the fracture geometry(e.g.height,aperture,and area)and fluid pressure evolutions of multiple hydraulic fractures placed in a porous reservoir interbedded with alternating stiff and soft layers are investigated using the model.The stress and pore pressure distributions within the layered reservoir during fluid injection are also presented.The simulation results reveal that stress umbrellas are easily to form among multiple hydraulic fractures’tips when propagating in soft layers,which impedes the simultaneous height growth.It is also observed that the impediment effect of soft layer is much more significant in the fractures suppressed by the preferential growth of adjoining fractures.After that,the combined effect of in situ stress ratio and fracturing spacing on the multi-fracture height growth is presented,and the results elucidate the influence of in situ stress ratio on the height growth behavior depending on the fracture spacing.Finally,it is found that the inclusion of soft layers changes the aperture distribution of outmost and interior hydraulic fractures.The results obtained from this study may provide some insights on the understanding of hydraulic fracture height containment observed in filed. 展开更多
关键词 Hydraulic fracturing Layered reservoir Simultaneous height growth In situ stress Fracture spacing Extended finite element method(XFEM) Cohesive zone method(CZM)
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Advances in seismological methods for characterizing fault zone structure
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作者 Yan Cai Jianping Wu +1 位作者 Yaning Liu Shijie Gao 《Earthquake Science》 2024年第2期122-138,共17页
Large earthquakes frequently occur along complex fault systems.Understanding seismic rupture and long-term fault evolution requires constraining the geometric and material properties of fault zone structures.We provid... Large earthquakes frequently occur along complex fault systems.Understanding seismic rupture and long-term fault evolution requires constraining the geometric and material properties of fault zone structures.We provide a comprehensive overview of recent advancements in seismological methods used to study fault zone structures,including seismic tomography,fault zone seismic wave analysis,and seismicity analysis.Observational conditions limit our current ability to fully characterize fault zones,for example,insufficient imaging resolution to discern small-scale anomalies,incomplete capture of crucial fault zone seismic waves,and limited precision in event location accuracy.Dense seismic arrays can overcome these limitations and enable more detailed investigations of fault zone structures.Moreover,we present new insights into the structure of the Anninghe-Xiaojiang fault zone in the southeastern margin of the Qinghai-Xizang Plateau based on data collected from a dense seismic array.We found that utilizing a dense seismic array can identify small-scale features within fault zones,aiding in the interpretation of fault zone geometry and material properties. 展开更多
关键词 fault zone structure TOMOGRAPHY fault zone wave seismic activity Anninghe-Xiaojiang fault zone
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Dynamic Identification and Evolution of Urban-suburban-rural Transition Zones Based on the Blender of Natural and Humanistic Factors: A Case Study of Chengdu, China
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作者 DENG Wei JIANG Zhenyuan +3 位作者 ZHANG Shaoyao REN Ping ZHANG Hao WANG Zhanyun 《Chinese Geographical Science》 SCIE CSCD 2024年第5期791-809,共19页
Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heter... Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heterogeneity across territorial spaces.As a super megacity in western China,Chengdu’s rapid urbanization has driven the evolution of U-S-R spaces,resulting in a sequential structure.To promote the high-quality spatial development of urban-rural region in a structured and efficient manner,it is essential to con-duct a scientific examination of the multidimensional interconnection within the U-S-RTZ framework.By proposing a novel identifica-tion method of U-S-RTZ and taking Chengdu,China as a case study,grounded in a blender of natural and humanistic factors,this study quantitatively delineated and explored the spatial evolutions of U-S-RTZ and stated the optimization orientation and sustainable devel-opment strategies of the production-living-ecological spaces along the U-S-R gradients.The results show that:1)it is suitable for the quantitative analysis of U-S-RTZ by established three-dimensional identification system in this study.2)In 1990-2020,the urban-sub-urban transition zones(U-STZ)in Chengdu have continuously undergone a substantial increase,and the scale of the suburban-rural transition zones(S-RTZ)has continued to expand slightly,while the space of rural-ecological transition zones(R-ETZ)has noticeably compressed.3)The landuse dynamics within U-S-RTZ has gradually increased in 1990-2020.The main direction of landuse transition was from farmland to construction land or woodlands,with the expansion of construction land being the most significant.4)R-ETZ primarily focus on ecological functions,and there is a trade-off relationship between the production-ecological function within the S-RTZ,and in the U-STZ,production-living composite functions are prioritized.This study emphasizes the importance of elastic planning and precise governance within the U-S-RTZ in a rapid urbanization region,particularly highlighting the role of suburbs as landscape corridors and service hubs in urban-rural integration.It elucidates to the practical implications for achieving high-quality development of integrated U-S-R territorial spaces. 展开更多
关键词 transition zone urban-suburban-rural zones spatial identification evolution mechanism Chengdu China
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Adaptive Integrated Coastal Zone Planning:History,Challenges,Advances,and Perspectives
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作者 WANG Xinyi SU Fenzhen +4 位作者 WANG Xuege PAN Tingting CUI Yikun LYNE Vincent YAN Fengqin 《Chinese Geographical Science》 SCIE CSCD 2024年第4期599-617,共19页
Coastal zones are dynamic,rich environments,now densely populated,and increasingly challenged by human and climatechange pressures.Effective long-term integrated coastal zone planning is needed to ensure sustainable e... Coastal zones are dynamic,rich environments,now densely populated,and increasingly challenged by human and climatechange pressures.Effective long-term integrated coastal zone planning is needed to ensure sustainable environmental protection and economic development.In this study,we reviewed the history of coastal zone planning since its birth in the 1950s based on the literature retrieved from the Web of Science(Core Collection)from 2000–2023,then summarized the tools and spatial allocation methods commonly used in the planning process,and finally proposed potential solutions to the challenges faced.The results show that after decades of development,coastal zone planning has changed from a decentralized activity to a targeted and integrated one,with an increasing emphasis on the ecosystem approach and the use of multiple planning tools.Spatial analysis techniques and environmental modelling software have become increasingly popular.Linear programming and overlay analysis are common approaches when performing spatial optimization,but land-sea interactions and planning in the marine parts still lack in-depth analysis and practical experience.We are also aware that the challenges posed by the integration of administrative hierarchies,scoping and conservation objectives,stakeholder participation,consideration of social dimensions,and climate change are pervasive throughout the planning process.There is an urgent need to develop more flexible and accurate spatial modelling tools,as well as more efficient participatory methods,and to focus on the holistic nature of the land-sea system to create more resilient and sustainable coastal zones. 展开更多
关键词 Integrated Coastal zone Management(ICZM) coastal zone planning spatial optimization ecosystem-based management
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Marginal zone lymphoma with severe rashes: A case report
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作者 Si-Jun Bai Ye Geng +7 位作者 Yi-Nan Gao Cai-Xia Zhang Qian Mi Chen Zhang Jia-Ling Yang Si-Jie He Zhen-YingYan Jian-Xia He 《World Journal of Clinical Cases》 SCIE 2024年第3期565-574,共10页
BACKGROUND Marginal zone lymphoma(MZL)is an indolent subtype of non-Hodgkin lymphoma(NHL),which is rare clinically with severe rashes as the initial symptom.CASE SUMMARY This study reports a case of MZL with generaliz... BACKGROUND Marginal zone lymphoma(MZL)is an indolent subtype of non-Hodgkin lymphoma(NHL),which is rare clinically with severe rashes as the initial symptom.CASE SUMMARY This study reports a case of MZL with generalized skin rashes accompanied by pruritus and purulent discharge.First-line treatment with rituximab combined with zanubrutinib had poor effects.However,after switching to obinutuzumab combined with zanubrutinib,the case was alleviated,and the rashes disappeared.CONCLUSION For patients with advanced stage MZL not benefiting from type I anti-CD20 monoclonal antibody(mAb)combination therapy,switching to a type II anti-CD20 mAb combination regimen may be considered.This approach may provide a new perspective in the treatment of MZL. 展开更多
关键词 Marginal zone lymphoma Mucosa-associated lymphoid tissue Extranodal marginal zone lymphoma Primary cutaneous marginal zone lymphoma Rituximab Obinutuzumab Zanubrutinib Case report
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Formation mechanism of fault accommodation zones under combined stress in graben basin:Implications from geomechanical modeling
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作者 Qi-Qiang Ren Jin-Liang Gao +3 位作者 Rong-Tao Jiang Jin Wang Meng-Ping Li Jian-Wei Feng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期54-76,共23页
A fault accommodation zone is a type of structure that is defined as regulating displacement and strain between faults structure.Increasing numbers of fault accommodation zones are being identified in graben basins,in... A fault accommodation zone is a type of structure that is defined as regulating displacement and strain between faults structure.Increasing numbers of fault accommodation zones are being identified in graben basins,indicating the potential exploration target and petroleum accumulation areas.This study aims to analyze the formation mechanism and development of fault accommodation zones under combined stress by a numerical simulation method considering geomechanical modeling.Using three-dimensional(3-D)seismic interpretation and fractal dimension method,exampled with the Dongxin fault zone,the fault activity and fault combination pattern were conducted to quantitatively characterize the activity difference in fault accommodation zones.Combined with mechanical experiment test,a geomehcanical model was established for fault accommodation zones in a graben basin.Integrating the paleostress numerical simulations and structural physical simulation experiment,the developmental characteristics and genetic mechanism of fault accommodation zones were summarized.Influenced by multi movements and combined stresses,three significant tectonic evolution stages of the Dongxing Fault Zone(DXFZ)were distinguished:During the E_(s)^(3)sedimentary period,the large difference in the stress,strain,and rupture distribution in various faults were significant,and this stage was the key generation period for the prototype of the DXFZ,including the FAZ between large-scale faults.During the E_(s)^(2)sedimentary period,the EW-trending symmetric with opposite dipping normal faults and the NE-SW trending faults with large scale were furtherly developed.The junction area of two secondary normal faults were prone to be ruptured,performing significant period for inheriting and developing characteristics of fault accommodation zones.During the Es1 sedimentary period,the high-order faults in the DXFZ exhibited the obvious fault depressions and strike-slip activity,and the fault accommodation zones were furtherly inherited and developed.This stage was the molded and formative period of the FAZ,the low-order faults,and the depression in the DXFZ. 展开更多
关键词 Fault accommodation zone Graben basin Fault activity Tectonic physical simulation experiment Finite element numerical simulation Dongxin fault zone
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