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Astronomical Site Monitoring System at Lijiang Observatory 被引量:5
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作者 Yu-Xin Xin Jin-Ming Bai +18 位作者 Bao-Li Lun Yu-Feng Fan Chuan-Jun Wang Xiao-Wei Liu Xiao Guang Yu Kai Ye Teng-Fei Song Liang Chang Shou-Sheng He Jji-Rong Mao Liang Xu Ding-Rong Xiong Xi-Liang Zhang Jian-Guo Wang Xu Ding Hai-Cheng Feng Xiang-Kun Liu Yang Huang Bing-Qiu Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第9期291-308,共18页
We installed two sets of Astronomical Site Monitoring Systems(ASMSs)at Lijiang Observatory(GMG),for the running of the 2.4-meter Lijiang optical telescope(LJT)and the 1.6-meter Multi-channel Photometric Survey Telesco... We installed two sets of Astronomical Site Monitoring Systems(ASMSs)at Lijiang Observatory(GMG),for the running of the 2.4-meter Lijiang optical telescope(LJT)and the 1.6-meter Multi-channel Photometric Survey Telescope(Mephisto).The Mephisto is under construction.The ASMS has been running on robotic mode since 2017.The core instruments:Cloud Sensor,All-Sky Camera and AutonomousDIMM that are developed by our group,together with the commercial Meteorological Station and Sky Quality Meter,are combined into the astronomical optical site monitoring system.The new Cloud Sensor's Cloud-Clear Relationship is presented for the first time,which is used to calculate the All-Sky cloud cover.We designed the Autonomous-DIMM located on a tower,with the same height as LJT.The seeing data have been observed for a full year.ASMS's data for the year 2019 are also analysed in detail,which are valuable to observers. 展开更多
关键词 Astronomical site monitoring System Lijiang Observatory Cloud Sensor Autonomous-DIMM
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Optimization of Shanghai marine environment monitoring sites by integrating spatial correlation and stratified heterogeneity 被引量:2
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作者 FAN Haimei GAO Bingbo +1 位作者 XU Ren WANG Jinfeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期111-121,共11页
The water quality grades of phosphate(PO4-P) and dissolved inorganic nitrogen(DIN) are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validat... The water quality grades of phosphate(PO4-P) and dissolved inorganic nitrogen(DIN) are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validation is used to determine the statistical inference method. To minimize absolute average errors and error mean squares,stratified Kriging(SK) interpolation is applied to DIN and ordinary Kriging(OK) interpolation is applied to PO4-P.Ten percent of the sites is adjusted by considering their impact on the change in deviations in DIN and PO4-P interpolation and the resultant effect on areas with different water quality grades. Thus, seven redundant historical sites are removed. Seven historical sites are distributed in areas with water quality poorer than Grade IV at the north and south branches of the Changjiang(Yangtze River) Estuary and at the coastal region north of the Hangzhou Bay. Numerous sites are installed in these regions. The contents of various elements in the waters are not remarkably changed, and the waters are mixed well. Seven sites that have been optimized and removed are set to water with quality Grades III and IV. Optimization and adjustment of unrestricted areas show that the optimized and adjusted sites are mainly distributed in regions where the water quality grade undergoes transition.Therefore, key sites for adjustment and optimization are located at the boundaries of areas with different water quality grades and seawater. 展开更多
关键词 area of water quality grade stratified Kriging(SK) leave-one-out cross validation method spatial simulated annealing method monitoring sites optimization
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Analysis on the noises from continuously monitoring GPS sites
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作者 黄立人 符养 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第2期206-211,共6页
In this paper, we analyze the time series of site coordinates of 27 continuously monitoring GPS sites covered by the Crustal Movement Observation Network of China over the whole country. The data are obtained in the p... In this paper, we analyze the time series of site coordinates of 27 continuously monitoring GPS sites covered by the Crustal Movement Observation Network of China over the whole country. The data are obtained in the period from the beginning of the observation to the November of 2005. On the basis of data processing, we analyze the power spectrum density of coordinate component noise at each site and calculate the spectral indexes manifesting the noise property of each component. The spectral indexes indicate that for most sites, the noise of time series of each coordinate component can be addressed by the model of white noise + flicker noise; and for a small amount of sites, it can be described by the model of white noise + flicker noise + random walk noise. We also quantitatively estimate each noise component in the model by using the criterion of maximum likelihood estimation. The result shows that the white noise in the time series of GPS site coordinates does not constitute the main part of noise. Therefore, the error estimation of site movement parameters is usually too small, or too optimistic if we consider the white noise only. Correspondingly, if this factor is not fully considered in explaining these movement parameters, it might mislead the readers. 展开更多
关键词 continuously monitoring GPS sites time series spectral index noise component maximumlikelihood estimation
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Aerosol composition at a coastal monitoring site in Hong Kong-initial results
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《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第4期14-28,共15页
AerosolcompositionatacoastalmonitoringsiteinHongKong—initialresultsK.S.Lam,L.Y.Chan,Z.L.ChengDepartmentofCiv... AerosolcompositionatacoastalmonitoringsiteinHongKong—initialresultsK.S.Lam,L.Y.Chan,Z.L.ChengDepartmentofCivilandStructuralEn... 展开更多
关键词 Aerosol composition at a coastal monitoring site in Hong Kong-initial results
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Research on Wireless Monitoring Technology of the Well Site Environment
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作者 Bo Chen Chaohao Zhang +2 位作者 Kui Deng Liang Ge Pan Hu 《Communications and Network》 2017年第2期101-110,共10页
Based on the characteristics of wireless communication technology and Wireless Sensor Network, this paper studies the well site environmental monitoring system. The relevant hardware and software of the system are des... Based on the characteristics of wireless communication technology and Wireless Sensor Network, this paper studies the well site environmental monitoring system. The relevant hardware and software of the system are designed to monitor the well site environment, thus preventing downhole accidents. The system uses the wireless ZigBee technology as the transmission mode, and combines the virtual instrument technology to design the upper machine interface. The test results show that the system can monitor the outdoor environment in real time. When the environmental parameters exceed the set value, the corresponding location of the LabVIEW interface will send an alarm. 展开更多
关键词 WELL site Environmental monitoring Wireless Communication TECHNOLOGY ZigBee Data ACQUISITION ROUTER COORDINATOR the UPPER Machine LabVIEW
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Measures for Quality Control of Air Monitoring Sites in Environmental Protection Projects
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作者 MENG Nana 《外文科技期刊数据库(文摘版)自然科学》 2021年第6期042-044,共5页
In the current rapid development of China's environmental protection cause, the construction and control work of environmental protection projects in various parts of the country are becoming more and stricter. Th... In the current rapid development of China's environmental protection cause, the construction and control work of environmental protection projects in various parts of the country are becoming more and stricter. Through the air monitoring of environmental protection projects, the actual operation value of environmental protection project construction can be well improved. However, there are still many external influencing factors in the field work of air monitoring, which have a negative impact on the quality of the overall monitoring work. Therefore, it is necessary to actively do a good job in the air monitoring of environmental protection projects. So as to ensure that the results of air monitoring can reflect the actual conditions of the atmosphere in the region, actively carry out the air monitoring and control work of environmental protection projects, enable the air monitoring work to be carried out to the maximum extent, and provide more help for the value of environmental projects. However, in the current air monitoring work of environmental protection projects, there are various problems, which have brought serious adverse effects to the overall air monitoring work of the project. Therefore, it is necessary to pay attention to the attention of relevant quality control staff, and to improve the quality of the air monitoring site of environmental protection projects. 展开更多
关键词 environmental protection engineering air monitoring site quality control measures and strategies
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浅埋偏压公路隧道初期支护非对称优化研究
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作者 孙雅珍 袁立凡 +2 位作者 王金昌 何放 王龙岩 《沈阳建筑大学学报(自然科学版)》 北大核心 2026年第1期47-57,共11页
研究浅埋偏压条件下公路隧道初期支护非对称优化方案,以确保隧道开挖过程中的稳定。依托新疆阿克特蒲1号隧道工程,通过理论计算及现场监测数据分析非对称支护的必要性,并建立三维偏压隧道模型,对喷射混凝土厚度、锚杆长度及锚杆间距进... 研究浅埋偏压条件下公路隧道初期支护非对称优化方案,以确保隧道开挖过程中的稳定。依托新疆阿克特蒲1号隧道工程,通过理论计算及现场监测数据分析非对称支护的必要性,并建立三维偏压隧道模型,对喷射混凝土厚度、锚杆长度及锚杆间距进行非对称优化设计,提出综合优化方案。结果表明:浅埋偏压条件下隧道左、右两侧围岩压力相差大,深埋侧围岩压力为浅埋侧的3.03倍;拱顶沉降呈现明显的非对称性,隧道两侧沉降值相差31.5 mm;通过增加喷射混凝土厚度、锚杆长度和锚杆间距可以有效控制隧道深埋侧的受力变形;适当减小浅埋侧的支护强度则可以充分发挥支护结构性能,协调隧道结构的应力与变形;经现场支护优化后发现,拱顶两侧沉降差值明显降低,偏压现象得到有效改善。采用非对称初期支护方案,可以有效减小浅埋偏压隧道结构两侧受力变形差异,确保隧道开挖过程中的稳定。 展开更多
关键词 浅埋偏压 初期支护 非对称优化 现场监测 数值模拟
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Mechanism of rock deformation and failure and monitoring analysis in water-rich soft rock roadway of western China 被引量:4
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作者 MENG Qing-bin HAN Li-jun +2 位作者 QIAO Wei-guo LIN Deng-ge YANG Ling 《Journal of Coal Science & Engineering(China)》 2012年第3期262-270,共9页
Aiming to get the strata behavior and stability rules of surrounding rock of the main return airway of Yushujing Coal Mine, convergence deformation of two sides and force of U-shaped steel yieldable support and bolt w... Aiming to get the strata behavior and stability rules of surrounding rock of the main return airway of Yushujing Coal Mine, convergence deformation of two sides and force of U-shaped steel yieldable support and bolt were monitored, and deformation of surrounding rock and mechanical characteristics of support structure were timely obtained to guide the informa- tion construction and optimize supporting parameters in water-rich soft rock roadway. The field monitoring results indicate the following. (1) Convergence displacement of rock surface increases with time continuity and shows surrounding rock's intense theological behavior. The original support scheme cannot control the large deformation and strongly theological behavior; (2) Without backfilling, the U-shaped steel support begins to bear load after erecting for 4-7 days and increases rapidly in the first 30 days. The U-shaped steel support at the right shoulder and top of roadway bears a larger force and the left side and shoulder bears a smaller force; (3) The stress of bolt increasing over time and at the right shoulder of roadway has larger growth and value. The mechanism of rock deformation and the failure and strata behavior in water-rich soft rock roadway are revealed based on the results of the measured relaxation zone of surrounding rock, measured stresses, and the rock mechanics tests. 展开更多
关键词 mining engineering soft rock roadway site monitoring DEFORMATION fracture mechanism
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某高寒地区露天边坡风险区域演化分析
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作者 赵昊童 王雨萌 +2 位作者 张鹏海 朱万成 徐晓冬 《有色金属(矿山部分)》 2026年第1期38-48,共11页
露天矿边坡地质条件复杂,滑坡影响因素多样,随露天矿体开采进程推进,边坡形态、开采力学响应状态等均会发生改变,因此需要结合实际工况,考虑开采深度等因素对滑坡风险区域演化进行综合评价。本文基于地勘资料及露天采场等高线模型,利用3... 露天矿边坡地质条件复杂,滑坡影响因素多样,随露天矿体开采进程推进,边坡形态、开采力学响应状态等均会发生改变,因此需要结合实际工况,考虑开采深度等因素对滑坡风险区域演化进行综合评价。本文基于地勘资料及露天采场等高线模型,利用3Dmine-Rhino7-FLAC3D等软件建立2023—2026年露天采场数值计算模型;利用现场监测与数值模拟相结合的方法分析采场边坡在开采扰动下的力学响应;提取应力-应变分析结果,结合坡度、高程、坡向等指标采用加权信息量法综合评价2023—2026各年边坡风险区域,并探究其演化规律。结果表明:采场2023年开采的数值模拟结果与现场监测结果具有较好的一致性;在开采过程中,应力逐渐向主要开采区域转移,边坡变形逐渐增加;考虑开采力学响应、地质条件等因素开展滑坡风险综合评价,在开采过程中风险区域的演化与扩张规律与开采进程有较好的一致性,最终得到滑坡风险区域的演化结果:高风险区域起初在北帮及西北帮滋生,逐渐向西帮以及西南帮推进,最后扩展至东南帮。 展开更多
关键词 露天边坡 数值模拟 现场监测 信息量法 风险区域演化
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降雨作用下堆积层滑坡稳定性预警方法研究
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作者 向春艳 马丽娜 《黑龙江科学》 2026年第2期29-32,37,共5页
堆积层滑坡由于其滑坡土体结构破碎、松散、力学性能较差,在持续降雨入渗下会易失稳,研究其稳定性预警方法十分重要。以甘肃省某滑坡为例,利用现场埋设的监测仪器数据,通过无限边坡模型计算,构建了基于降雨量与地下水位值的滑坡稳定性... 堆积层滑坡由于其滑坡土体结构破碎、松散、力学性能较差,在持续降雨入渗下会易失稳,研究其稳定性预警方法十分重要。以甘肃省某滑坡为例,利用现场埋设的监测仪器数据,通过无限边坡模型计算,构建了基于降雨量与地下水位值的滑坡稳定性预警模型并验证了其可靠性。结果表明,滑坡地下水位呈周期性变化规律,其动力响应规律与降雨时间存在一周的滞后期。得出了滑坡稳定性预警模型及滑坡各项阈值,与现场监测数据进行对比验证分析,该滑坡处于稳定状态,可为同类堆积层滑坡在降雨作用下的安全预警提供理论依据及借鉴意义。 展开更多
关键词 堆积层滑坡 现场监测 无限边坡模型 滑坡稳定性预警
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大断面饱和黄土隧道塌方处置及效果分析
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作者 肖乐 《价值工程》 2026年第1期104-107,共4页
富水饱和黄土含水率高、稳定性差、承载力低使得大断面隧道在穿越饱和黄土层时极易发生塌方事故。研究针对某大断面隧道塌方事故,运用FLAC3D软件并结合现场实测数据,分析了塌方原因,提出现场塌方处理措施。结果表明:饱和黄土层处于拱顶... 富水饱和黄土含水率高、稳定性差、承载力低使得大断面隧道在穿越饱和黄土层时极易发生塌方事故。研究针对某大断面隧道塌方事故,运用FLAC3D软件并结合现场实测数据,分析了塌方原因,提出现场塌方处理措施。结果表明:饱和黄土层处于拱顶处支护结构受力较大,过大的变形量导致隧道掌子面周边围岩产生松动圈,进而发生坍塌、地表塌陷;处治后塌方段初期支护和二次衬砌的变形趋于稳定,且均未发生异常变化,处治效果良好。研究结果可为类似隧道工程塌方处治提供借鉴。 展开更多
关键词 黄土隧道 塌方 现场监测 数值分析 处治措施
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复杂地质隧道聚能水压爆破关键技术研究
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作者 陈文达 《建筑机械》 2026年第1期309-314,共6页
为解决隧道爆破施工中存在的超欠挖问题,减小爆破振动对围岩的破坏,文章以岳圩1号隧道为研究对象,采用现场监测的方法分析聚能水压爆破作用机理及损伤演化过程,并且对聚能水压爆破技术进行了分析与总结。研究结果表明:炮泥堵塞会导致应... 为解决隧道爆破施工中存在的超欠挖问题,减小爆破振动对围岩的破坏,文章以岳圩1号隧道为研究对象,采用现场监测的方法分析聚能水压爆破作用机理及损伤演化过程,并且对聚能水压爆破技术进行了分析与总结。研究结果表明:炮泥堵塞会导致应力在孔内部积聚并逐渐增强,进而影响到整个孔道内的应力波及作用时间,从而决定了爆破破碎的范围和程度;上部水压力聚能爆破后,损伤区的分布较为均匀,而下部结构在遭受水压力聚能爆破时,损伤区主要出现在孔口和孔底;当围岩达到稳定时,左右线隧道拱顶变形最大,在施工过程中应着重关注拱顶变形情况。 展开更多
关键词 隧道爆破 聚能水压 现场监测 应力 位移
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Exploiting satellite SAR for archaeological prospection and heritage site protection
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作者 Francesca Cigna Timo Balz +4 位作者 Deodato Tapete Gino Caspari Bihong Fu Michele Abballe Haonan Jiang 《Geo-Spatial Information Science》 CSCD 2024年第3期526-551,共26页
Optical and Synthetic Aperture Radar(SAR)remote sensing has a long history of use and reached a good level of maturity in archaeological and cultural heritage applications,yet further advances are viable through the e... Optical and Synthetic Aperture Radar(SAR)remote sensing has a long history of use and reached a good level of maturity in archaeological and cultural heritage applications,yet further advances are viable through the exploitation of novel sensor data and imaging modes,big data and high-performance computing,advanced and automated analysis methods.This paper showcases the main research avenues in this field,with a focus on archaeological prospection and heritage site protection.Six demonstration use-cases with a wealth of heritage asset types(e.g.excavated and still buried archaeological features,standing monuments,natural reserves,burial mounds,paleo-channels)and respective scientific research objectives are presented:the Ostia-Portus area and the wider Province of Rome(Italy),the city of Wuhan and the Jiuzhaigou National Park(China),and the Siberian“Valley of the Kings”(Russia).Input data encompass both archive and newly tasked medium to very high-resolution imagery acquired over the last decade from satellite(e.g.Copernicus Sentinels and ESA Third Party Missions)and aerial(e.g.Unmanned Aerial Vehicles,UAV)platforms,as well as field-based evidence and ground truth,auxiliary topographic data,Digital Elevation Models(DEM),and monitoring data from geodetic campaigns and networks.The novel results achieved for the use-cases contribute to the discussion on the advantages and limitations of optical and SAR-based archaeological and heritage applications aimed to detect buried and sub-surface archaeological assets across rural and semi-vegetated landscapes,identify threats to cultural heritage assets due to ground instability and urban development in large metropolises,and monitor post-disaster impacts in natural reserves. 展开更多
关键词 Synthetic Aperture Radar(SAR) interferometric SAR(InSAR) multispectral imagery cultural heritage crop mark archaeological prospection site monitoring Unmanned Aerial vehicle(UAV)surveying
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危险废物填埋污染地块地下水长期监测指标优化研究
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作者 朱文会 程亮 +3 位作者 王恭伟 赵珂 陶亚 卢然 《中国环境科学》 北大核心 2026年第1期258-268,共11页
针对地块尺度地下水风险管控项目长期监测指标缺乏优化调整方法的短板,以某大型危险废物填埋污染地块为研究对象,通过收集施工期、效果评估期和长期监测期已有地下水监测数据,构建地下水监测井超标决策的特征数据集,并采用卡方自动交叉... 针对地块尺度地下水风险管控项目长期监测指标缺乏优化调整方法的短板,以某大型危险废物填埋污染地块为研究对象,通过收集施工期、效果评估期和长期监测期已有地下水监测数据,构建地下水监测井超标决策的特征数据集,并采用卡方自动交叉检验、穷举卡方自动交叉检验、分类与回归树三种决策树模型,识别影响地下水监测井超标的关键监测指标.结果表明,决策树应用于地下水监测井超标情况预测是可行的.分类与回归树模型在准确率、精度、召回率、精度和召回率的调和平均方面的性能均显著优于卡方自动交叉检验和穷举卡方自动交叉检验模型,分类与回归树模型的总体优化算法可能更适合地下水监测井超标情况预测.1,2,4-三氯苯和镍对分类与回归树模型地下水监测井超标情况预测的能力有非常重要影响,氟化物、石油烃、三氯甲烷、二氯甲烷、镉、顺-1,2-二氯乙烯也对该模型的预测能力有重要影响,建议在后续的地下水长期监测工作中着重关注这8项监测指标的污染变化. 展开更多
关键词 危险废物填埋 污染地块 地下水长期监测 决策树
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Gaseous elemental mercury concentration in atmosphere at urban and remote sites in China 被引量:26
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作者 WANG Zhang-wei CHEN Zuo-shuai +1 位作者 DUAN Ning ZHANG Xiao-shan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第2期176-180,共5页
An investigation of gaseous elemental mercury concentration in atmosphere was conducted at Beijing and Guangzhou urban, Yangtze Delta regional sites and China Global Atmosphere Watch Baseline Observatory (CGAWBO) in... An investigation of gaseous elemental mercury concentration in atmosphere was conducted at Beijing and Guangzhou urban, Yangtze Delta regional sites and China Global Atmosphere Watch Baseline Observatory (CGAWBO) in Mt. Waliguan of remote continental area of China. High temporal resolved data were obtained using automated mercury analyzer RA-915^+. Results showed that the overall hourly mean Hg^0 concentrations in Mt. Waliguan were 1.7±1.1 ng/m3 in summer and 0.6±0.08 ng/m^3 in winter. The concentration in Yangtze Delta regional site was 5.4±4.1 ng/m^3, which was much higher than those in Waliguan continental background area and also higher than that found in North America and Europe rural areas. In Beijing urban area the overall hourly mean Hg^0 concentrations were 8.3±3.6 ng/m^3 in winter, 6.5±5.2 ng/m^3 in spring, 4.9±3.3 ng/m^3 in summer, and 6.7±3.5 ng/m^3 in autumn, respectively, and the concentration was 13.5±7.1 ng/m^3 in Guangzhou site. The mean concentration reached the lowest value at 14:00 and the highest at 02:00 or 20:00 in all monitoring campaigns in Beijing and Guangzhou urban areas, which contrasted with the results measured in Yangtze Delta regional site and Mr. Waliguan. The features of concentration and diurnal variation of Hg^0 in Beijing and Guangzhou implied the importance of local anthropogenic sources in contributing to the high Hg^0 concentration in urban areas of China. Contrary seasonal variation patterns of Hg^0 concentration were found between urban and remote sites. In Beijing the highest Hg^0 concentration was in winter and the lowest in summer, while in Mt. Waliguan the Hg^0 concentration in summer was higher than that in winter. These indicated that different processes and factors controlled Hg^0 concentration in urban, regional and remote areas. 展开更多
关键词 gaseous elemental mercury urban/remote sites monitorING
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Monitoring biofouling based on aerobic respiration in reverse osmosis system
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作者 Youngjae Yu Keun-Young Park +5 位作者 Jaehyun Jung Wonjung Song Jaehyeok Kim Junhee Ryu Harshad Lade Jihyang Kweon 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第4期247-256,共10页
A monitoring method of biofouling in reverse osmosis(RO) system was proposed based on the fluorescent signal of resorufin, which is reduced by nicotinamide adenine dinucleotide released from viable cells during aerobi... A monitoring method of biofouling in reverse osmosis(RO) system was proposed based on the fluorescent signal of resorufin, which is reduced by nicotinamide adenine dinucleotide released from viable cells during aerobic respiration. The fluorescent signal of resorufin reduced by planktonic cells and microorganisms of biofilm showed linearity, indicating its feasibility to monitor biofouling in a RO system. For the application of the method to the lab-scale RO system, the injection concentration of resazurin and the injection flow rate were optimized. Biofilm on RO membranes continuously operated in a lab-scale RO system was estimated by resorufin fluorescence under optimized detection condition. As a result,resorufin fluorescence on RO membrane showed a significant increase in which the permeability of RO system decreased by 30.48%. Moreover, it represented the development of biofilm as much as conventional biofilm parameters such as adenosine triphosphate,extracellular polymeric substances, and biofilm thickness. The proposed method could be used as a sensitive and low-cost technology to monitor biofouling without autopsy of membranes. 展开更多
关键词 ON-site monitorING Biofilm Aerobic RESPIRATION RESAZURIN reduction mechanism RESORUFIN fluorescence
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CO_(2)地质封存岩石力学问题研究进展 被引量:4
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作者 于子望 卢帅屹 +1 位作者 白林 郑天琪 《吉林大学学报(地球科学版)》 北大核心 2025年第3期930-942,共13页
温室气体排放导致全球气候变化严重,世界各国正在采取措施缓解碳排放造成的温室效应。二氧化碳捕集与封存(CCS)作为一种大规模的温室气体减排技术正在兴起,并逐渐成为缓解温室效应的最重要手段之一。该技术在实施过程中存在一系列问题,... 温室气体排放导致全球气候变化严重,世界各国正在采取措施缓解碳排放造成的温室效应。二氧化碳捕集与封存(CCS)作为一种大规模的温室气体减排技术正在兴起,并逐渐成为缓解温室效应的最重要手段之一。该技术在实施过程中存在一系列问题,其中注入封存引起的地质力学问题不容忽视。本文综述了CCS中由于注入封存引发的地质力学问题所带来的影响和危害。结果表明:CO_(2)注入引发孔隙压力变化、热应力及化学-力学耦合作用,导致储层岩石强度降低、变形加剧,进而引发地表变形;InSAR技术能够有效监测地表变形,场地微震监测揭示了注入速率与地震活动的直接关联,控制注入速率与压力可有效降低盖层破裂与断层活化的概率;数值模拟是评估场地地质力学风险的主要手段,场地盖层优先选择低渗透、低反应性岩石,可减少泄漏风险,并且需综合断层应力状态规避高活动性断层区域。 展开更多
关键词 CO_(2)地质封存 场地监测 数值模拟 岩石力学 热效应
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准噶尔盆地非常规储层水力压裂监测技术进展 被引量:3
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作者 张士诚 李建民 +5 位作者 许江文 谢勃勃 王明星 吕振虎 李嘉成 杨鹏 《天然气工业》 北大核心 2025年第4期70-84,共15页
准噶尔盆地非常规油气资源丰富,勘探开发潜力巨大,但水力压裂开发过程中面临着储层改造体积有限、油气采出程度低和开发成本高等挑战,亟需明确地下储层水力裂缝展布形态,解决水力压裂优化设计难题。为此,在系统总结北美非常规储层水力... 准噶尔盆地非常规油气资源丰富,勘探开发潜力巨大,但水力压裂开发过程中面临着储层改造体积有限、油气采出程度低和开发成本高等挑战,亟需明确地下储层水力裂缝展布形态,解决水力压裂优化设计难题。为此,在系统总结北美非常规储层水力压裂监测试验关键认识的基础上,聚焦玛湖凹陷致密砾岩油藏和吉木萨尔凹陷页岩油藏开展的水力压裂现场监测试验,系统梳理井下鹰眼监测、DAS管外光纤监测和大斜度取心试验的结果,揭示了非常规油气储层增产改造机制,为国内非常规储层压裂优化设计和裂缝监测解释提供了依据。研究结果表明:①储层非均质性增强导致水平井段内各簇孔眼冲蚀程度差异更加明显,多簇裂缝扩展形态非均衡程度更强;②提升排量能够有效促进多簇裂缝均匀改造,而差异化布孔和段内暂堵压裂不能完全解决多裂缝非均衡扩展问题;③玛湖砾岩井下取心结果显示水力裂缝空间分布不均匀,人工裂缝数量远大于射孔簇数;④储层中穿砾裂缝数量是绕砾裂缝的2倍左右,两类水力裂缝均以高角度为主,裂缝走向与最大水平主应力方向一致;⑤支撑剂在水平方向上主要集中在10~23 m内,垂向上主要集中在20~25 m范围内;⑥砾石颗粒越大、砾石排列方向与裂缝扩展方向夹角越大,水力裂缝越容易穿过砾石。结论认为:压裂结束后段簇间的产液贡献能力存在动态变化,储层综合品质、压裂改造程度与压后产能的联系仍需进一步研究;现场系统监测结果对完善非常规油气藏压裂优化设计、推动水力压裂技术发展具有重要意义,技术体系还需整体谋划和系统推进水力压裂试验场研究。 展开更多
关键词 准噶尔盆地 玛湖砾岩油藏 吉木萨尔页岩油 水力压裂现场监测试验 井下鹰眼监测 分布式光纤监测 大斜度井取心试验
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隧道装配式临时支撑结构力学特性 被引量:1
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作者 乔雄 倪伟淋 +1 位作者 扈士静 杨小龙 《科学技术与工程》 北大核心 2025年第4期1688-1700,共13页
针对隧道临时支撑施工中的不足,提出临时支撑装配化,并从临时支撑形状、装配化结构、受力变形等方面对该新型结构展开研究。以邵家塘隧道为背景,统计现场监测数据,并利用有限元软件将其与传统临时支撑结构进行对比分析可得:隧道后行洞... 针对隧道临时支撑施工中的不足,提出临时支撑装配化,并从临时支撑形状、装配化结构、受力变形等方面对该新型结构展开研究。以邵家塘隧道为背景,统计现场监测数据,并利用有限元软件将其与传统临时支撑结构进行对比分析可得:隧道后行洞开挖时会对先行洞的变形造成不利影响。竖直临时支撑对隧道左、右拱腰、地表沉降以及总收敛变形的控制较好,与传统弧形相比,分别减小了16%、20%、55%和14%,且竖直临时支撑能够更快恢复稳定,可缩短拆撑距。采用竖直临时支撑,隧道初支受力相比弧形支撑更小、更安全,竖向和横向最大应力分别减小了58%、73%。采用ABAQUS软件对临时支撑局部结构的力学特性进行了模拟,结果表明:装配式竖直和传统临时支撑结构的受力与变形均能满足规范要求。但装配式临时支撑结构在施工效率和经济效益方面更有优势,选用装配式临时支撑更合适。 展开更多
关键词 隧道工程 装配化结构 数值模拟 临时支撑 现场监测
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Analysis of Factors Affecting the Quality of Field Sampling in Environmental Monitoring
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作者 LI Bingbing 《外文科技期刊数据库(文摘版)自然科学》 2021年第3期052-055,共6页
With the ecological environment problem becoming more and more serious, it poses a great threat to human existence. The environmental monitoring work should be further strengthened to scientifically evaluate the envir... With the ecological environment problem becoming more and more serious, it poses a great threat to human existence. The environmental monitoring work should be further strengthened to scientifically evaluate the environmental pollution problems, so as to provide a basis for formulating more scientific and effective environmental governance and maintenance strategies. Field sampling is one of the important links in environmental monitoring and is an important basis for environmental monitoring and evaluation. Through the comprehensive analysis of the quality influencing factors of environmental monitoring field sampling, strengthening the quality control of field sampling can provide a more realistic and effective reference basis for environmental monitoring and strengthen the effect of environmental monitoring. 展开更多
关键词 environmental monitoring site sampling quality influence factor
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