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Surrounding Rock Failure Mechanism and Control Technology of Gob-Side Entry with Triangle Coal Pillar at Island Longwall Panel in 15 m Extra-Thick Coal Seams
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作者 Hao Sun 《World Journal of Engineering and Technology》 2024年第2期373-388,共16页
Taking the return air roadway of Tashan 8204 isolated island working face as the background, the evolution law of the stress field in the surrounding rock of the widened coal pillar area roadway during the mining peri... Taking the return air roadway of Tashan 8204 isolated island working face as the background, the evolution law of the stress field in the surrounding rock of the widened coal pillar area roadway during the mining period of the isolated island working face is obtained through numerical simulation. The hazardous area of strong mine pressure under different coal pillar widths is determined. Through simulation, it is known that when the width of the coal pillar is less than 20 m, there is large bearing capacity on the coal side of the roadway entity. The force on the side of the coal pillar is relatively small. When the width of the coal pillar ranges from 25 m to 45 m, the vertical stress on the roadway and surrounding areas is relatively high. Pressure relief measures need to be taken during mining to reduce surrounding rock stress. When the width of the coal pillar is greater than 45 m, the peak stress of the coal pillar is located in the deep part of the surrounding rock, but it still has a certain impact on the roadway. It is necessary to take pressure relief measures to transfer the stress to a deeper depth to ensure the stability of the triangular coal pillar during the safe mining period of the working face. This provides guidance for ensuring the stability of the triangular coal pillar during the safe mining period of the working face. 展开更多
关键词 Island Coal Face Evolution Law of surrounding Rock Stress Field Strong Mine Pressure Hazardous Area
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Spatial effect of environmental regulation measures on industrial structure upgrading from the empirical analysis of Beijing-Tianjin-Hebei region and its surrounding areas 被引量:1
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作者 Guoxing Zhang Peide Zhang +2 位作者 Nana Deng Haixu Bao Jiexun Li 《Chinese Journal of Population,Resources and Environment》 2019年第3期267-277,共11页
This paper investigates the spatial effect of environmental regulation measures on the upgrading of industrial structure in the integrated development strategy of Beijing-Tianjin-Hebei region and its surrounding areas... This paper investigates the spatial effect of environmental regulation measures on the upgrading of industrial structure in the integrated development strategy of Beijing-Tianjin-Hebei region and its surrounding areas.In order to reflect the effect of the environmental regulation and different regulation measures more truly,this paper constructs indices of the environmental regulation measures through the results of policy texts quantification.On the basis of the previous research,this paper divides environmental regulation into the following types:personnel and administrative measures of command and control;market-oriented fiscal,taxation,financial and other economic measures;guidance measures.Spatial panel regression results show that administrative measures of command control and market-oriented fiscal measures have a significant role in promoting regional industrial structure upgrading,but not conducive to the advancement of the industrial structure of adjacent areas.Their roles in promoting and inhibition are counteracted,which causes the total effect of industrial structure upgrading of Beijing-Tianjin-Hebei and the surrounding areas are not significant.Personnel measures,financial measures,other economic measures and guidance measures do not have the short-term effect and spatial effect on the upgrading of industrial structure. 展开更多
关键词 Beijing-Tianjin-Hebei and its surrounding areas policy quantification environmental regulatory measures upgrading of industrial structure
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Deformation-strain field in Sichuan and its surrounding areas based on GPS data 被引量:1
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作者 Chen Fuchao Ta La Chen Juzhong 《Geodesy and Geodynamics》 2015年第3期203-209,共7页
The strain rate in Sichuan and its surrounding areas, and the activity rate and strain rate in two block boundary fault zones were calculated according to the block movement parameters estimated using the station spee... The strain rate in Sichuan and its surrounding areas, and the activity rate and strain rate in two block boundary fault zones were calculated according to the block movement parameters estimated using the station speed obtained from regional GPS station observation data in these areas for 2009e2011 and GPS continuous station data for 2011e2013. The movement field characteristics in these areas were analyzed with the Sichuan Basin as the reference. Results show that the principal strain rate and maximum shear strain rate of the Bayan Har block were the largest, followed by those of the Sichuane Yunnan block and Sichuan Basin. The deep normal strain rate in the Longmenshan fault zone was compressive and large over the study period. The normal strain rate in the Xianshuihe fault zone was tensile. 展开更多
关键词 Sichuan and its surrounding areas Displacement vec
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Research into the Regional Characteristics of the Tectonic Stress Field in Jiashi, Xinjiang and Its Surrounding Areas
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作者 Gao Guoying Wang Haitao Nie Xiaohong Long Haiying 《Earthquake Research in China》 2007年第4期397-408,共12页
Jiashi and its surrounding areas are composed of many structural zones. Using the focal mechanism solutions of 59 moderately strong earthquakes in Jiashi and its surrounding areas, and combining these with the calcula... Jiashi and its surrounding areas are composed of many structural zones. Using the focal mechanism solutions of 59 moderately strong earthquakes in Jiashi and its surrounding areas, and combining these with the calculation results of system cluster and stress field inversion, we aualyzed the evolvement characteristics of the stress field for different times and different regions. The results were as follows: The earthquakes in Jiashi are mainly strike-slip. However, those of the Kalpin block are mainly reverse events, showing an obvious thrusting. The regional characteristics are different from other areas. The direction of the regional principal stress field is near NS. However, under different tectonic backgrounds, the directions of the stress fields are different. The direction of the principal compress stress is near NS in the Kashi-Wuqia area. But before and after the 3 earthquakes with M7.0, dynamic evolution from NW to NS and then to NE with time process was observed. The Kalpin block has been dominated by a consistent stress field in the NW direction for a long time. However, the direction of the stress field of the Jiashi region is NE. Since 1996, the direction of the regional stress field has changed obviously. The direction of the P axis was deflected towards the NE, and the plunge angle increased. The result shows clearly the regional characteristics and variation of the distribution pattern of the stress field in different tectonic environments. 展开更多
关键词 Focal mechanism solution Tectonic stress field Region characteristic Jiashi andits surrounding area
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Impacts and Countermeasures of Climate Change on Animal Husbandry in Qinghai Plateau and Its Surrounding Area 被引量:8
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作者 李红梅 李林 +1 位作者 邓振镛 黎明 《Agricultural Science & Technology》 CAS 2010年第7期138-144,共7页
The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annua... The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annual mean temperature,annual mean maximum temperature and annual mean minimum temperature showed an increasing trend in Qinghai plateau during the time from 1961 to 2008; the annual precipitation had not obvious change,but the obvious feature of seasonal change; wind speed and sunshine hours showed a decreasing trend during the time from 1961 to 2008.Secondly,under the current climate condition,grassland productivity showed a decreasing trend,and the grassland theoretical capacity affected by grassland productivity decreased too; warm winter was in favor of livestock overwintering safely,which resulted in a high level of the survival rate of young stock; temperature increasing and precipitation decreasing were beneficial to the fatness of livestock,but the meat yield of livestock was affected by some negative factors such as grassland degradation; livestock diseases had a close relationship with weather condition,and adverse weather condition may arose many diseases of livestock.Thirdly,in view of the current problems of livestock production,we took a series of countermeasures including grass industry construction,livestock improvement,developing new modes of animal husbandry,control and prevention of stockbreeding diseases and insect pests and recovery of meteorological disasters,which played a important role in promoting grassland productivity,solving the problem of the imbalances between livestock and forage,protecting the ecological environment and improving livestock performance. 展开更多
关键词 Climate change Qinghai plateau and its surrounding area Animal Husbandry Impact COUNTERMEASURES
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Mountain Land Use Planning of Metropolitan Suburbs:the Case of the Jinyun Mountain and Its Surrounding area,Chongqing,China 被引量:14
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作者 SHAO Jingan WEI Chaofu XIE Deti 《Journal of Mountain Science》 SCIE CSCD 2005年第2期116-128,共13页
Open space of metropolitan suburbs in mountain region, has been increasingly becoming the coupling mosaic structure of industrial actions and landscape behaviors. However, the local governments, when making land use p... Open space of metropolitan suburbs in mountain region, has been increasingly becoming the coupling mosaic structure of industrial actions and landscape behaviors. However, the local governments, when making land use planning, often aim at economic development, and rarely refer to the coordination of compatibilities and conflicts between industrial actions and landscape behaviors in the mosaic structure. In this study land use in the Jinyun Mountain and its surrounding area, Chongqing is adjusted by gray multi-objective programming approach and local-level decision-making process to cope with conflicts between objectives for human welfare and objectives for landscape conservation. The results indicate that: 1) the compatibilities and conflicts among different behavior characters and different landscape types result in the compatibilities of landscape to human behavior; 2) a land use planning in the study area is produced based on the sustainable land use and social-eco development, which pays more attention to the resources and environment constraints and economic objectives, and follows the distribution law of rare resources; 3) in the study area, cultivated land of 1,207.27 ha can meet the demands for food and byproducts by the residents there, orchard land and forestland of 632.55 ha, 2,276.61 ha, respectively can provide enough spaee for the local people to improve their living structure and meet their demands for reereational activities, and urban residential land, rural residential land, mining land and transportation land of 1107.60 ha, 120.27 ha, 162.48 ha, 100.91 ha, respeetively can satisfy the resident's eeonomie development and infrastructures; 4) the equilibrium among industrial actions, landscape accessibility and ecological conservation can be obtained by analyzing the possible impaets of human activities on landscape eeologieal proeess in open spaee of metropolitan suburbs in mountain areas. 展开更多
关键词 Mountain land use planning metropolitan suburbs land optimal allocation Jinyun Mountain and its surrounding area CHONGQING
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On Innovation of Coordinative Development Mechanism of Science and Technology Park with Surrounding Areas under Promotion of the Government——Case Study on Three Science and Technology Park in Dongguan
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作者 Zhao Shushan 《International Journal of Technology Management》 2016年第6期66-68,共3页
Science and Technology Park, which plays a very important role in promoting rapid development of regional economy, has enjoyed various preferential policies in its unique development since China’s reform and opening ... Science and Technology Park, which plays a very important role in promoting rapid development of regional economy, has enjoyed various preferential policies in its unique development since China’s reform and opening up, which oppositely shows that the government has overlooked development outside the park and resulted in negative competition between the science and technology park and surrounding areas in resources and industry development, etc. Therefore, it is necessary and urgent to overcome the existing obstacles against coordinative development between the park and surrounding areas, to explore paths where the two can development coordinately and to achieve new breakthrough and innovation in coordinative development in subject, object, platform and mechanism. 展开更多
关键词 Science and Technology PARK and the surrounding areas mechanism INNOVATION sharing and WIN-WIN situation government PROMOTION Dongguan
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Effects of Social and Economic Development of Regions Surrounding Chao Lake on Water Quality Change of Chao Lake 被引量:1
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作者 赵腾飞 王晴晴 +2 位作者 唐晓先 刘西军 张云华 《Agricultural Science & Technology》 CAS 2015年第12期2866-2869,共4页
The research analyzed social and economic development around Chao Lake as well as changes of water quality in Chao Lake and explored the relation- ships of local population and GDP with water chemical oxygen demand (... The research analyzed social and economic development around Chao Lake as well as changes of water quality in Chao Lake and explored the relation- ships of local population and GDP with water chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), chlorophyll and eutrophication index. The re- sults showed that population around Chao Lake and GDP kept growing from 2001 to 2013, and water quality was improving. In addition, correlation analysis indicated that except of water eutrophication, GDP and population showed inverse correlation with other indices, demonstrating that water quality has been effectively controlled in Chao Lake recently. 展开更多
关键词 surrounding Chao Lake areas Water quality of Chao Lake Social and economic development Correlation analysis
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Features of gas geology and its main controlling factors in Pingxiang Mining Area, Jiangxi Province
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作者 ZHAO Zhi-gen YAN Jia-ping LIU Xing 《Journal of Coal Science & Engineering(China)》 2012年第3期271-275,共5页
Pingxiang Mining Area in Jiangxi Province is one of the major coal-producing areas and is prone to serious coal and gas outburst, therefore, it is of significance to research on gas geological features and its control... Pingxiang Mining Area in Jiangxi Province is one of the major coal-producing areas and is prone to serious coal and gas outburst, therefore, it is of significance to research on gas geological features and its controlling factors. Based on the analysis of gas data collected from geological exploration and coal mining, the research reveals that the features of gas geology vary significantly between west part and east part of Pingxiang Mining Area, and it is characterized by high gas mines with se- rious coal and gas outburst in the west part and low gas mines with no coal and gas outburst in the east part. The main controlling factors to gas geology are discussed, and the great difference of gas geology between west part and east part is the result of comprehensive effect by geological factors. Concerning the gas generation, the coal rank in the west part is higher than that in the east part, which is favorable to generate more gas in the west part than in the east part. Concerning the gas preservation, the structures are characterized by gliding nappe in the west part and by tectonic window in the east part, the surrounding rocks are characterized by poor permeability in the west part and comparatively good permeability in the east part, and the characteristics of coal rank and coal body structure are favorable to gas preservation in the west part and favorable to gas emission in the east part. 展开更多
关键词 Pingxiang Mining Area coal and gas outburst gliding nappe coal rank surrounding rock
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废弃矿区周边受污染水体生物修复技术
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作者 王亚宇 李敏 《能源与环保》 2024年第3期47-52,共6页
废弃矿区中受污染的水体可能会渗入地下水或河流,导致附近的水源污染。为此,采用生物修复技术,对废弃矿区周边受污染水体的修复方法展开研究。分析了矿区周边环境以及相关气候信息,确定该矿区周边污染水体污染物分布特征,根据分布结果... 废弃矿区中受污染的水体可能会渗入地下水或河流,导致附近的水源污染。为此,采用生物修复技术,对废弃矿区周边受污染水体的修复方法展开研究。分析了矿区周边环境以及相关气候信息,确定该矿区周边污染水体污染物分布特征,根据分布结果布设样本测试点;利用生物膜法在样本测试点中进行污染水体的修复,修复过程中,需要对微生物实施培养、驯化,进一步增加微生物降解污水的活性;将驯化好的污泥转置进IC厌氧反应器中,产生氧化生物膜,投入测试点水域中,通过污泥吸附作用产生氧化生物膜,实现污染水体生物修复。实验结果表明,利用生物膜方法对污染水体进行修复,能够有效去除水体中总石油烃、多环芳烃等污染物质,并中和水体酸碱度,使水体完成修复后达到可排放安全标准。 展开更多
关键词 废弃矿区 周边受污染水体 生物修复技术 生物膜法
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基于监测台网加速度信号分析的上海周边区域地震影响评价
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作者 任晓崧 任广震 +1 位作者 王泽亚 宗刚 《结构工程师》 2024年第2期101-109,共9页
2021年11月至2023年8月期间,上海市周边区域共发生了5次有感地震,分别为江苏盐城市大丰区海域5.0级、江苏常州市天宁区4.2级、黄海海域4.8级、上海市青浦区3.1级和山东德州市平原县5.5级地震,同济大学监测台网的4个测站捕获了这5次地震... 2021年11月至2023年8月期间,上海市周边区域共发生了5次有感地震,分别为江苏盐城市大丰区海域5.0级、江苏常州市天宁区4.2级、黄海海域4.8级、上海市青浦区3.1级和山东德州市平原县5.5级地震,同济大学监测台网的4个测站捕获了这5次地震的场地和典型结构加速度信号,分析了各次地震作用下场地和典型结构的加速度信号的峰值及持时,探讨了各次地震信号的反应谱特征,对照设计反应谱曲线的第一特征段和第二特征段,对这5次周边区域地震对上海市的影响进行评价。 展开更多
关键词 上海周边区域 有感地震 场地加速度峰值 楼层加速度峰值 反应谱
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元代后太原地区石匠刻工考究
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作者 王崇恩 张璇 胡川晋 《建筑与文化》 2024年第5期284-286,共3页
太原境内的民间石匠数量较多,这些工匠工作的地域范围主要分布在太原周边地区,其中以古交市、娄烦县、晋源区、尖草坪区这四处为中心。除了本县石匠外,还有崞县和稷山等地的外来石匠。多数石匠间的关系为兄弟、父子或师徒,有部分石匠参... 太原境内的民间石匠数量较多,这些工匠工作的地域范围主要分布在太原周边地区,其中以古交市、娄烦县、晋源区、尖草坪区这四处为中心。除了本县石匠外,还有崞县和稷山等地的外来石匠。多数石匠间的关系为兄弟、父子或师徒,有部分石匠参与多个地区的活动。碑碣的题材内容因地而异,大致分为记事类、墓志铭类和其他类。文章通过对元代后太原地区的石匠刻工进行历史回顾及深入研究,探讨了其留下的历史、科学与艺术价值。 展开更多
关键词 元代后 太原及周边地区 碑碣 石匠 科学价值与艺术价值
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哈尔滨城建初期中东铁路附属地城市街道网络形态的演进与基因解析(1898-1926)
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作者 唐岳兴 徐一书 赵志庆 《当代建筑》 2024年第7期126-129,共4页
本文基于哈尔滨城建史界定城建初期的时间范围,利用历史舆图与sDNA技术分析城建初期中东铁路附属地城市街道网络形态的演进逻辑,并运用“特征识别-共性归纳-基因解析”的方法解析街道网络形态基因。研究表明.城建初期(1898-1926)附属地... 本文基于哈尔滨城建史界定城建初期的时间范围,利用历史舆图与sDNA技术分析城建初期中东铁路附属地城市街道网络形态的演进逻辑,并运用“特征识别-共性归纳-基因解析”的方法解析街道网络形态基因。研究表明.城建初期(1898-1926)附属地先后形成了老哈尔滨、新市街、埠头区等区域的街道网络,本文将其归类为五种形态特征单元,以及它们组合形成的“枝干形”与“放射形”两类街道网络形态基因,体现出西方规划思想与本土地域特征的双重影响。 展开更多
关键词 街道网络形态 中东铁路附属地 城建初期 形态基因
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西安都市圈生态系统服务价值与人类活动强度的时空关系 被引量:3
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作者 朱琳娜 赵牡丹 +2 位作者 李云绯 樊艺 王建 《生态与农村环境学报》 CAS CSCD 北大核心 2024年第3期325-334,共10页
人类活动是影响生态系统服务价值(ecosystem service value,ESV)变化的重要原因之一,对两者时空关系的研究有助于生态环境与社会经济协调发展。以西安都市圈为研究对象,基于1990、2000、2010和2018年4期土地利用数据,在2 km×2 km... 人类活动是影响生态系统服务价值(ecosystem service value,ESV)变化的重要原因之一,对两者时空关系的研究有助于生态环境与社会经济协调发展。以西安都市圈为研究对象,基于1990、2000、2010和2018年4期土地利用数据,在2 km×2 km格网尺度下构建ESV评估模型、ESV流向损益模型、人类活动强度(human activity intensity,HAI)指数评估模型和双变量空间自相关模型,探讨ESV与人类活动强度的时空关系。结果表明:(1)1990—2018年间,西安都市圈ESV在时间尺度上呈持续下降趋势,近30年间共降低12.8亿元;在空间尺度上呈现以西安主城区为中心向外围递增的分布格局;(2)ESV增益主要源于耕地转为林地、水域和草地;ESV亏损主要源于耕地、建设用地的转入以及水域的转出;(3)人类活动强度整体呈现以西安主城区为中心向南北递减的空间分布格局,高影响区集中分布在西安主城区及其周边地区,低影响区分布于研究区南北两端;(4)ESV与人类活动强度呈负相关关系,两者聚类关系以低-高和高-低聚集方式为主,低-高和高-低聚集区域显著性水平高。期望通过对ESV与人类活动强度的空间关系分析为区域可持续发展提供理论支持。 展开更多
关键词 生态系统服务价值 人类活动强度 格网尺度 双变量空间自相关性 西安都市圈
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复采巷道过空巷交叉段围岩控制技术 被引量:1
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作者 吕建光 张慧友 +1 位作者 顾伟 徐大龙 《煤矿安全》 CAS 北大核心 2024年第1期176-184,共9页
以宇昌煤业复采区地质条件下回采巷道的围岩控制为工程背景,针对与空巷相交区围岩破碎支护困难的问题,对回采巷道破碎段的围岩控制技术方案及参数进行研究。采用理论计算得出回采巷道煤柱稳定的理论宽度,并通过数值计算得出交叉巷道三... 以宇昌煤业复采区地质条件下回采巷道的围岩控制为工程背景,针对与空巷相交区围岩破碎支护困难的问题,对回采巷道破碎段的围岩控制技术方案及参数进行研究。采用理论计算得出回采巷道煤柱稳定的理论宽度,并通过数值计算得出交叉巷道三角区煤柱弹性核区宽度小于2 m时,需要采用架棚的支护方式维护巷道稳定;通过对掘采期间巷道围岩应力及变形的理论计算及数值模拟分析,确定了合理的架棚支护区域及支护方案;现场实测表明,采用锚网索和工字钢棚联合支护的方式,巷道变形量得到了有效控制。 展开更多
关键词 复采区 空巷 三角煤柱 围岩控制 数值模拟
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四川盆地及周缘筇竹寺组与五峰组-龙马溪组页岩孔隙结构对比
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作者 谢国梁 焦堃 +3 位作者 刘瑞崟 邓宾 叶玥豪 刘树根 《成都理工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第5期813-832,共20页
四川盆地及周缘筇竹寺组、五峰组-龙马溪组2套页岩是目前中国海相页岩气勘探的主攻层位,但页岩气勘探效果差异较大。为进一步探究这2套海相页岩储层的微观孔隙结构特征及其差异,采用定性和定量相结合的方法(包括场发射扫描电子显微镜、... 四川盆地及周缘筇竹寺组、五峰组-龙马溪组2套页岩是目前中国海相页岩气勘探的主攻层位,但页岩气勘探效果差异较大。为进一步探究这2套海相页岩储层的微观孔隙结构特征及其差异,采用定性和定量相结合的方法(包括场发射扫描电子显微镜、低压CO_(2)/N_(2)吸附、多重分形分析)对研究区筇竹寺组、五峰组-龙马溪组页岩的孔隙结构进行精细表征和对比,并揭示两者的成因机制差异。结果表明,研究区筇竹寺组、五峰组-龙马溪组页岩孔隙结构在孔隙发育程度及类型、孔径分布以及微孔、介孔-宏孔连通性、非均质性等方面存在明显差异。相较于筇竹寺组,五峰组-龙马溪组页岩具有有机质孔隙更为发育、孔隙度高、孔隙连通性较低、非均质性更强、微孔占比高以及孔隙比表面积和孔体积高等特征。导致筇竹寺组、五峰组-龙马溪组页岩孔隙结构差异的原因包括:①沉积环境差异导致两者页岩岩相不同,进而影响原始孔隙的有效保存;②机械压实作用、有机质热成熟作用、热成熟阶段页岩系统的封闭性以及深埋藏阶段强烈的机械压实作用是造成2套页岩孔隙结构差异的关键成岩作用。五峰组-龙马溪组由于其高的生物硅质含量、适中的热演化程度、相对封闭的页岩系统、相对较浅的埋藏作用和相对稳定的构造条件更有利于页岩中残余无机孔隙及有机质孔隙的发育和有效保存。 展开更多
关键词 孔隙结构 成因差异机制 五峰组-龙马溪组 筇竹寺组 四川盆地及周缘
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高密度城区游憩绿道网络规划的整合性框架研究——以西安市中心城区为例
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作者 王丁冉 周庆华 +1 位作者 聂川林 雒梓涵 《规划师》 CSSCI 北大核心 2024年第10期97-104,共8页
通过构建整合网络识别、情景规划、效益评估的综合规划框架,以西安市中心城区为例,在网络识别阶段选取不同等级的游憩资源,运用成本连通性模型识别潜在的游憩绿道网络,进而在情景规划阶段提出底线、优化、理想3种情景的方案,并在效益评... 通过构建整合网络识别、情景规划、效益评估的综合规划框架,以西安市中心城区为例,在网络识别阶段选取不同等级的游憩资源,运用成本连通性模型识别潜在的游憩绿道网络,进而在情景规划阶段提出底线、优化、理想3种情景的方案,并在效益评估阶段针对不同情景从出行便捷度、资源连接度、服务覆盖度3个维度进行定量评估,旨在为存量更新背景下高密度城区游憩绿道网络规划提供决策支持。 展开更多
关键词 高密度城区 游憩绿道网络 网络识别 情景规划 效益评估 西安市
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CMA-MESO模式对2020年夏季四川盆地及周边降水预报性能的评估
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作者 叶茂 吴钲 +1 位作者 翟丹华 陈法敬 《大气科学》 CSCD 北大核心 2024年第5期1901-1915,共15页
利用2020年夏季(6~8月)CMA-MESO模式逐日08:00(北京时,下同)起报的12~36 h逐时降水预报数据和地面—卫星—雷达三源融合逐时降水产品,着眼于小时尺度降水特征,细致评估了CMA-MESO对四川盆地及周边地区的降水预报性能。结果表明,CMA-MES... 利用2020年夏季(6~8月)CMA-MESO模式逐日08:00(北京时,下同)起报的12~36 h逐时降水预报数据和地面—卫星—雷达三源融合逐时降水产品,着眼于小时尺度降水特征,细致评估了CMA-MESO对四川盆地及周边地区的降水预报性能。结果表明,CMA-MESO较好把握了夏季降水的空间分布特征,即小时平均降水量和降水频率的大值区位于四川盆地西部、北部和东部的高海拔山区,而降水强度大值区主要位于山脉迎风坡一侧,但CMA-MESO预报的降水量和频率大值区位置较观测偏南。CMA-MESO合理描述了研究区域内降水量和频率峰值时间位相自西向东逐步滞后的特征,能够把握区域平均的降水量和频率清晨主峰、傍晚次峰的双峰形态以及降水强度的单峰特征,但预报的降水日变化位相超前于观测。CMA-MESO预报的逐时降水量均大于观测,明显的降水量预报正偏差发生于夜间(21:00至次日03:00)和午后至傍晚(14:00~20:00),分别由一般性降水(0.1~10 mm h-1)预报偏差和强降水(≥10 mm h-1)预报偏差主导,其偏差大值区分别位于青藏高原东南缘至四川盆地西部和四川盆地以东、以南地区,模式对热力和动力场的预报偏差结合地形的影响是降水量预报偏差的成因。 展开更多
关键词 四川盆地及周边 小时尺度降水特征 CMA-MESO 模式 预报降水评估
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环梵净山区域畜禽养殖污染量估算及负荷预警研究
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作者 田文勇 毛昆 张翊红 《家畜生态学报》 北大核心 2024年第1期82-90,共9页
为了解环梵净山区域畜禽养殖污染与环境保护之间是否存在现实矛盾,文章运用排污系数法与土地承载法估算2014-2021年该区域畜禽养殖污染量并对其负荷预警进行分析。结果表明:(1)区域畜禽粪尿、TP、TN污染物排放量总体呈上升趋势,其中粪... 为了解环梵净山区域畜禽养殖污染与环境保护之间是否存在现实矛盾,文章运用排污系数法与土地承载法估算2014-2021年该区域畜禽养殖污染量并对其负荷预警进行分析。结果表明:(1)区域畜禽粪尿、TP、TN污染物排放量总体呈上升趋势,其中粪尿排放量依次是牛>猪>家禽>羊,TP排放量趋于平稳,TN变化趋势较大,各乡镇畜禽粪尿、TP、TN排放量差异较大,其中德旺乡的排放量最多,太平镇最少,其余乡镇变化不大;(2)区域猪粪当量、N、P负荷总体处于上升态势,N、P最大负荷量均未超过欧盟标准,各乡镇负荷变化趋势差异较大,部分乡镇的负荷值已经超过区域均值,污染负荷问题较为严重;区域内畜禽污染预警等级存在上升趋势,污染风险逐渐增大,除太平镇无污染外,其余乡镇在不同时间段均存在污染,负荷预警问题严峻。由此提出调整畜禽养殖结构,合理控制畜禽饲养规模,严格落实保护区规定,精准实施污染治理政策,加大养殖主体技能培训,拓宽养殖主体就业渠道等对策建议。 展开更多
关键词 环梵净山区域 畜禽养殖 污染量估算 负荷预警 粪尿污染物
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瑶渠煤矿大巷间煤柱尺寸确定及支护优化
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作者 路贝 张波 +1 位作者 张浩 解盘石 《陕西煤炭》 2024年第4期6-11,共6页
为研究大巷过剥蚀区时大巷间煤柱合理尺寸及围岩稳定性,以瑶渠煤矿西采区Ⅱ回风大巷为研究对象,采用理论分析、数值模拟等研究方法,建立了煤柱尺寸计算模型,揭示了煤柱在8 m、10 m、12 m、14 m条件下巷道围岩应力、位移及塑性区的分布规... 为研究大巷过剥蚀区时大巷间煤柱合理尺寸及围岩稳定性,以瑶渠煤矿西采区Ⅱ回风大巷为研究对象,采用理论分析、数值模拟等研究方法,建立了煤柱尺寸计算模型,揭示了煤柱在8 m、10 m、12 m、14 m条件下巷道围岩应力、位移及塑性区的分布规律,确定了过剥蚀区大巷间煤柱的合理尺寸,并优化了西采区Ⅱ回风大巷的支护参数。研究结果表明,瑶渠煤矿西采区Ⅱ回风大巷与辅运大巷之间煤柱尺寸由14 m减小至8 m时,巷道围岩内的垂直应力由1.381 MPa增加至1.465 MPa、最大位移量增加了12.52%,塑性区逐渐贯通煤柱。当煤柱尺寸为10 m时,煤柱塑性区处于贯通的临界区域,煤柱内部具有一定的弹性核区域,且煤柱尺寸大于理论计算的9.23 m,能够满足巷道围岩的稳定性。综合考虑,确定煤柱最小合理尺寸为10 m。对10 m煤柱尺寸下西采区Ⅱ回风大巷进行支护优化,采用帮部3根锚杆支护后巷道围岩应力、位移和塑性区均显著改善,保证了巷道围岩的稳定性。 展开更多
关键词 剥蚀区 大巷 煤柱尺寸 围岩支护 塑性区 垂直应力
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