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A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures

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Petroleum Science 2024年第1期21卷 162-181页

作者： Yan-Xiao He Shang-Xu Wang Gen-Yang Tang Chao Sun Hong-Bing Li San-Yi Yuan Xian Wei Li-Deng Gan Xiao-Feng Dai Qiang Ge Peng-Peng Wei Hui-Qing Zhang National Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationCollege of GeophysicsChina University of Petroleum(Beijing)Beijing102249China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116JiangsuChina Research institute of Petroleum Exploration and Development CNPCBeijing100083China Beijing Vocational College of labour and Social Security Beijing100029China PetroChina Dagang Oilfield Exploration and Development Research institute CNPCTianjin300280China

Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure *** with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]*** Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent *** dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the *** particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective *** addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion.

关键词： Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow

GM Crops Controversy： Stakeholder Analysis of the Case of Bt Brinjal （Eggplant） in India

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Journalism and Mass Communication 2012年第8期2卷 852-863页

作者： Pingali Venugopal xavier labour relations institute Jamshedpur India

Bt cotton a genetically modified （GM） crop has provided higher yields and profits for the farmers in India since its introduction in 2002. The environmentalists across the globe have however expressed the concern on the use of GM crops as they feel that they would cause environmental damage and they are not safe for human consumption. In the meantime, the Genetic Engineering Approval Committee （the regulatory body for GM crops in India） evaluated the development process of Bt brinjal （eggplant） and has given its approval for commercial cultivation. This further aggravated the GM controversy; while the farmers are interested in cultivating Bt brinjal, the activists against GM crops have been protesting against the introduction of these hybrids stating that adequate tests have not been done to check on the safety of Bt brinjal. This controversy prompted the Minister of Environment of India Government to hold public consultations across India to access the views of the stakeholders. Based on the public consultations, the minister ＂put on hold the commercial introduction of Bt brinjal＂ on February 9, 2010. This paper analyses the view points of stakeholders collected at the public consultation held at Hyderabad on January 31, 2010. The analysis shows that the stakeholders develop different orientation based on the ＂stage of need hierarchy they are in＂ and the attributes they use to evaluate the outcome. The paper concludes that the views of the activist groups based on their limited understanding could get the introduction of Bt brinjal stalled as the companies failed in public communication and education. Policy implications are drawn for government consideration.

关键词： GM crops Bt brinjal stakeholder analysis India

Emissions of fluorides from welding processes

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Journal of Environmental Sciences 2015年第11期27卷 179-183页

作者： Malgorzata Szewczynska Emilia Pagowska Krystyna Pyrzynska Department of Chemical and Aerosol Hazards Central Institute for Labour Protection-National Research Institute Faculty of Chemistry University of Warsaw

The levels of fluoride airborne particulates emitted from welding processes were investigated. They were sampled with the patented IOM Sampler, developed by J. H Vincent and D. Mark at the institute of Occupational Medicine（IOM）, personal inhalable sampler for simultaneous collection of the inhalable and respirable size fractions. Ion chromatography with conductometric detection was used for quantitative analysis. The efficiency of fluoride extraction from the cellulose filter of the IOM sampler was examined using the standard sample of urban air particle matter SRM-1648 a. The best results for extraction were obtained when water and the anionic surfactant N-Cetyl-N-N-Ntrimethylammonium bromide（CTAB） were used in an ultrasonic bath. The limits of detection and quantification for the whole procedure were 8 μg/L and 24 μg/L, respectively The linear range of calibration was 0.01–10 mg/L, which corresponds to 0.0001–0.1 mg of fluorides per m3 in collection of a 20 L air sample. The concentration of fluorides in the respirable fraction of collected air samples was in the range of 0.20–1.82 mg/m3, while the inhalable fraction contained 0.23–1.96 mg/m3 of fluorides during an eight-hour working day in the welding room.

关键词： Fluorides Particle size distribution Welding processes

Socio-scientific quantification of the comprehensive benefits of debris flow mitigation measures for villages in western Sichuan, China

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Journal of Mountain Science 2024年第5期21卷 1598-1612页

作者： DENG Ting XU Pei LI Ming LU Yafeng WANG Yukuan LI Zhengyang SHRAVAN Kumar Ghimire institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China University of Chinese Academy of Sciences Beijing 100049China

Debris flow hazards seriously threaten thesafety and sustainable development of mountainousareas. Numerous debris flow mitigation measures havebeen implemented worldwide;however, acomprehensive assessment of the specific disasterreduction effects of these measures and their economic,social and ecological benefits is yet to be *** western region of Sichuan Province frequentlysuffers from geohazards such as debris flow, and thegovernment has adopted many mitigation *** study assessed the benefits of debris flowmitigation measures and identified the key influencingfactors via a field-based study conducted in 81 villagesin western Sichuan province, China. A framework forthe evaluation of the benefits of rural debris flowmitigation measures was constructed andquantitatively evaluated using a survey. Snowballsampling was performed to recruit 81 village leadersand 468 farmers. The results showed that managementand engineering measures were the main methodsused to mitigate debris flow;ecological measures wereauxiliary. The average satisfaction scores of farmers forthese three types of measures were 4.07, 3.90, and 3.56,respectively (as measured on a five-point Likert scale).In contrast, in terms of the benefits of these mitigationmeasures, only a small proportion of villages (11.11%)obtained a high level of comprehensive benefits fromthe debris flow mitigation measures, while the majority(88.89%) received medium to low-level benefits. Toimprove this situation, we further studied and foundthat the main factors that restricted villages fromachieving high-level comprehensive benefits were theunpredictable nature of debris flows, labour forceoutflow and remoteness. Effective control measures, agood economic environment and strong governmentassistance were reported as crucial factors forimproving these comprehensive benefits. This studyprovides socio-scientific references for decisionmakingon rural debris flow mitigation measures while keeping villages at the

关键词： Mitigation measures Comprehensive benefit evaluation Debris flow Mountain development Rural areas

Construction and evaluation of a novel end-column amperometric detection system for electrophoresis microchips

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Science China Chemistry 2010年第1期53卷 250-256页

作者： CHEN ZhiFeng1,GAO YunHua2,WANG Li3,CHU XiaoGang1 1Chinese Academy of Inspection and Quarantine,Beijing 100123,China 2Technical institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China 3Beijing institute of labour Protection,Beijing 100054,China Chinese Academy of Inspection and Quarantine Beijing China Technical institute of Physics and Chemistry Chinese Academy of Sciences Beijing China Beijing institute of labour Protection Beijing China

A set of integrated end-column amperometric detection system has been developed,onto which an electrophoresis microchip can be conveniently *** machined by a piece of transparent organic glass,the system consists of an electrophoresis microchip platform and an amperometric detection reservoir,in which the microchip can be fixed onto the platform by microchip grooves and with stainless steel *** detection electrode can be directly fixed in the amperometric detection reservoir by screws and *** dopamine as the model analyte,we take platinum disc electrodes with different diameters of 100 μm,300 μm and 500 μm and a carbon fiber electrode with the diameter of 240 μm as the working electrode,all of which accomplish sensitive *** detection parameters of the system are optimized with the carbon fiber *** detection results show that in the electrochemical cleaning procedure,the relative deviations of 3.2% and 0.5% for the peak current and retention time,respectively,can be obtained for the successive detections of 100 μM dopamine,and the limit of detection for dopamine can reach 0.4 μM(S/N = 3).This system is small,but its performance of detection is stable and sensitive,and the replacement of its working electrodes is convenient,so it is very suitable as a universal platform of end-column amperometric detection for electrophoresis microchips.

关键词： electrophoresis microchip amperometric detection dopamine evaluation

Analysis of pile rows on noise reduction of building vibration caused by subway operation

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Yantu Lixue/Rock and Soil Mechanics 2020年 41卷 209-218页

作者： Wu, Yu-Bin Song, Rui-Xiang Wu, Ya-Nan He, Lei Liu, Bi-Ding Beijing Municipal institute of labour Protection Beijing 100054 China

With the rapid development of subway construction, the impacts of vibration of neighboring subway and structure-borne noise on building get more and more obvious. Pile rows have gradually become one of the effective methods on controlling the vibration of metro. The vibration isolation mechanism, efficiency of pile rows on site soil environmental vibration and design parameters have been studied relatively mature. However, the controlling effect of pile rows on floor vibration and noise of indoor structure is rarely reported. In this paper, taking the new building near the ground line of throat area in metro depot as an object, on the basis of vibration test of building floor and site soil, the 3D finite element model is applied to systematically study the controlling effect of pile rows on the vibration of building floor and indoor secondary structure noise, and also the parameter impacts. It shows that the configuration location of pile rows and buried depth have obvious impacts on isolating the indoor vibration of buildings and structure-borne noise. The controlling effect is affected by the dynamic characteristics of buildings and floors. The control effect of different floors and rooms differs greatly. It is necessary to carry out special design in engineering application. The results can provide useful information for engineering design of pile rows in controlling the vibration of subway. © 2020, Science Press. All right reserved.

关键词： Piles

Supporting farmer-managed irrigation systems in the Shigar valley, Karakorum： Role of the government and Aga Khan Rural Support Programme

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Journal of Mountain Science 2017年第10期14卷 2064-2081页

作者： Joseph K.W.HILL Department of Rural Management Xavier Institute of Social Sciences (XISS) Dr Gamil Bulcke Path Post Box 7 Ranchi- 834001 India

Farmer-managed irrigation systems(FMIS) in the high altitude valleys of the Karakorum,Pakistan, continue to be managed effectively despite increased pressure on the social arrangements that sustain them. Colonial era records shows that over a century ago government agencies undertook irrigation support projects. In the past three decades,government agencies and the non-government agency Aga Khan Rural Support Programme(AKRSP), which channels foreign funds into the region, have actively engaged in the provision of irrigation support. This article seeks to explore whether such projects support or undermine farmer-managed irrigation systems and the complex institutional arrangements that underpin them. Field research using ethnographic and participatory methods was conducted in spring 2013 in the upper Shigar valley, Skardu district, GilgitBaltistan. The findings show that irrigation development is a political activity that involves village-based actors, religious leaders, local politicians,and government and non-government *** agencies operate in a largely top-down,engineering mode, their larger projects limited to villages suffering water scarcity. The local government provides small funds for renovation work of FMIS,though allocation of funds is highly politicized. Nongovernment agencies, for a variety of reasons including donor-funding cycles, apply a one-size-fitsall ‘participatory' model in an attempt to socially engineer rules and institutions. In communities divided by factionalism the use of such external models that stress formation of committees are unlikely to yield positive results, and could instead contribute to undermining the very systems they seek to support. This research argues that irrigation interventions should take care to build upon the rich and complex social arrangements that have sustained FMIS through the centuries.

关键词： Farmer-managed irrigation systems Institutional arrangements Government Aga Khan Rural Support Programme Shigar valley Karakorum

A new implementation of FLEXPART with Enviro-HIRLAM meteorological input,and a case study during a heavy air pollution event

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Big Earth Data 2024年第2期8卷 397-434页

作者： Benjamin Foreback Alexander Mahura Petri Clusius Carlton xavier Metin Baykara Putian Zhou Tuomo Nieminen Victoria Sinclair Veli-Matti Kerminen Tom V.Kokkonen Simo Hakala Diego Aliaga Risto Makkonen Alexander Baklanov Roman Nuterman Men Xia Chenjie Hua Yongchun Liu Markku Kulmala Pauli Paasonen Michael Boy Aerosol and Haze Laboratory Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijingChina institute for Atmospheric and Earth System Research/Physics Faculty of ScienceUniversity of HelsinkiHelsinkiFinland Division of Nuclear Physics Department of PhysicsLund UniversityLundSweden Swedish Meteorological and Hydrological institute(SMHI) Research DepartmentUnit of Meteorology/Environment and ClimateNorrköpingSweden Climate and Marine Sciences Department Eurasia Institute of Earth SciencesIstanbul Technical UniversityIstanbulTurkey Department of Physics Faculty of ScienceUniversity of HelsinkiHelsinkiFinland Department of Meteorology(MISU)and Bolin Centre for Climate Research Stockholm UniversityStockholmSweden Climate System Research Unit Finnish Meteorological InstituteHelsinkiFinland Science and Innovation Department World Meteorological Organization(WMO)GenevaSwitzerland Niels Bohr institute University of CopenhagenCopenhagenDenmark Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric SciencesNanjing UniversityNanjingChina School of Engineering Science Lappeenranta-Lahti University of Technology(LUT)LappeenrantaFinland Atmospheric Modelling Centre Lahti Lahti University CampusLahtiFinland

We integrated Enviro-HIRLAM(Environment-High Resolution Limited Area Model)meteorological output into FLEXPART(FLEXible PARTicle dispersion model).A FLEXPART simulation requires meteorological input from a numerical weather prediction(NWP)*** publicly available version of FLEXPART can utilize either ECMWF(European Centre for Medium-range Weather Forecasts)Integrated Forecast System(IFS)forecast or reanalysis NWP data,or NCEP(*** Center for Environmental Prediction)Global Forecast System(GFS)forecast or reanalysis NWP *** primary benefits of using Enviro-HIRLAM are that it runs at a higher resolution and accounts for aerosol effects in meteorological *** compared backward trajectories gener-ated with FLEXPART using Enviro-HIRLAM(both with and without aerosol effects)to trajectories generated using NCEP GFS and ECMWF IFS meteorological inputs,for a case study of a heavy haze event which occurred in Beijing,China in November *** found that results from FLEXPART were considerably different when using different meteorological *** aerosol effects were included in the NWP,there was a small but noticeable differ-ence in calculated ***,when looking at potential emission sensitivity instead of simply expressing trajectories as lines,additional information,which may have been missed when looking only at trajectories as lines,can be inferred.

关键词： Atmospheric and chemical transport modelling trajectory and particle dispersion modelling severe air pollution episode FLEXPART Enviro-HIRLAM

Noise propagation characteristics of underground equipment in coal mines

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Journal of Coal Science & Engineering(China) 2012年第3期18卷 320-324页

作者： CHENG Gen-yin WEI Zhi-yong XU Ming ZHU Yan-yan North China institute of Science and Technology Sanhe 065201China Beijing Municipal institute of labour Protection Beijing 100054China

On the basis of the survey of underground noise in Jinggezhuang and Donghuantuo mines, Kailuan Group, noise radiation intensity, noise propagation properties and noise frequency-spectrum characteristics of underground equipment were studied at different work conditions. The result indicates that the noise source intensity surpasses the noise limit requirement of 85 dBA completely. Nearly 70% noise sources exceed the noise limit of 90 dBA, and some are over 100 dBA. Noise attenua- tion in semi-free field environment on the ground is significantly different from underground far-field environment of noise source in coal mines. Noise of these regions, where staffs are long and highly concentrated, exceeds 85 dBA, the basic noise limit. The noise frequency-spectrum presents the wideband characteristics. Especially in the main frequency of the language communication 500, 1 000 and 2 000 Hz, the octave band of noise performs obviously.

关键词： noise in coal mine noise propagation property noise frequency-spectrum characteristic