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渤海湾西岸的第一道贝壳堤的年代学研究及1千年来的岸线变化

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海洋地质与第四纪地质 2000年第2期20卷 7-14页

作者：王宏张金起张玉发李建芬李凤林 mark van strydonck Veerle Hendrix 中国地质调查局天津地调中心天津300170 Royal Institute for Culture Heritage

取自堤下部的 1 4 C平均校正年龄表明 ,渤海湾西岸沿现代海岸线展布的第一道贝壳堤 ( 堤 )的初始年龄约在 90 0～ 70 0 cal BP/AD10 5 0～ 12 5 0 ,堤的发育延续至 18、19世纪。以往 1 4 C数据因取样位置不当 (一般取自堤的中部 ) ,不... 详细信息

取自堤下部的 1 4 C平均校正年龄表明 ,渤海湾西岸沿现代海岸线展布的第一道贝壳堤 ( 堤 )的初始年龄约在 90 0～ 70 0 cal BP/AD10 5 0～ 12 5 0 ,堤的发育延续至 18、19世纪。以往 1 4 C数据因取样位置不当 (一般取自堤的中部 ) ,不能用于支持文献中关于该堤起始时间的判断 ;但是这批数据连同文献中获自岸外残存贝壳碎屑堆积层的数据 ,暗示隋、唐贝壳堤存在的可能性。近 1千年来该地区贝壳堤的发育反映了海岸线的重大变化。

关键词：渤海湾贝壳堤年代学海岸线变化碳同位素

Geologic data collection and assessment techniques in coal mining for ground control

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International Journal of Mining Science and Technology 2020年第1期30卷 131-139页

作者： mark van Dyke Ted Klemetti Joe Wickline NIOSH Pittsburgh15236 PAUSA Coronado Global Resources Inc. BeckleyWVUSA

The identification and mitigation of adverse geologic conditions are critical to the safety and productivity of underground coal mining *** anticipate and mitigate adverse geologic conditions,a formal method to evaluate geotechnical factors must be *** mine is unique and has its own separate approach for defining what an adverse geological condition consists *** collection of geologic data is a first critical step to creating a geological database to map these hazards efficiently and *** considerations must be taken into account,such as lithology of immediate roof and floor strata,seam height,gas and oil wells,faults,depressions in the mine floor(water)and increases in floor elevation(gas),overburden,streams and horizontal stress directions,amongst many other *** geologic data is collected,it can be refined and integrated into a database that can be used to develop maps showing the trend,orientation,and extent of the adverse geological *** information,delivered in a timely manner,allows mining personnel to be proactive in mine planning and support implementations,ultimately reducing the impacts of these *** paper covers geologic exploratory methods,data organization,and the value of collecting and interpreting geologic information in coal mines to enhance safety and *** implementation of the methods described above has been proven effective in predicting and mitigating adverse geologic conditions in underground coal *** re-evaluation of data collection methods,geologic interpretations,mapping procedures,and communication techniques ensures continuous improvement in the accuracy of predictions and mitigation of adverse geologic *** a concise record of the work previously done to track geologic conditions at a mine will allow for the smoothest transition during employee turnover and *** refinements and standardization of data collection methods,

关键词： Roof control Database Mapping Hazards Geology

Direct evidence of microbiological water quality changes on bacterial quantity and community caused by plumbing system

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Journal of Environmental Sciences 2022年第6期34卷 175-183页

作者： Jun Li Anran Ren Ed van der mark Gang Liu Key Laboratory of Drinking Water Science and Technology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Dunea Water Company Plaza of the United Nations 11-15Zoetermeer 2700 ATthe Netherlands Sanitary engineering Department of Water managementFaculty of Civil Engineering and GeosciencesDelft University of TechnologyDelft 2600 GAthe Netherlands

Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compared the water quality in the water main and at customer tap by preparing a sampling tap on the water main. The biomass was quantified by adenosine triphosphate(ATP) and the microbial community was profiled by 454 *** results showed that in distribution pipes, biofilm contributed >94% of the total biomass,while loose deposits showed little contribution(< 2%) because of the low amount of loose deposits. The distribution of biological stable water had minor effects on the microbiocidal water quality regarding both quantity(ATP 1 ng/L vs. 1.7 ng/L) and community of the bacteria. Whereas the plumbing system has significant contribution to the increase of active biomass(1.7 ng/L vs. 2.9 ng/L) and the changes of bacterial community. The relative abundance of Sphingomonas spp. at tap(22%) was higher than that at water main(2%), while the relative abundance of Pseudomonas spp. in tap water(15%) was lower than that in the water from street water main(29%). Though only one location was prepared and studied, the present study showed that the protocol of making sampling tap on water main offered directly evidences about the impacts of plumbing system on tap water quality, which makes it possible to distinguish and study the processes in distribution system and plumbing system separately.

关键词： Drinking water distribution system Plumbing system Microbiological water quality Sampling program 454 pyrosequencing

Coal mine entry rating system:A case study

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International Journal of Mining Science and Technology 2021年第1期31卷 145-151页

作者： mark A.van Dyke Ted M.Klemetti Craig Compton National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

Coal mines are continuously seeking to determine the performance of entries with different ground control products and installation *** are many factors that impact how an entry will perform which include but are not limited to geology,overburden,bolting type and pattern,and mine *** the National Institute for Occupational Safety and Health(NIOSH),research has been instituted to examine the relationship of the parts of a coal mine entry as a system and not as individual *** study this relationship,the first step in this study was to create a numeric rating system that accurately reflects visual observations of the mine entry and is easy to *** researchers devised this rating system to improve upon previous ideas,offering increased flexibility which can be incorporated into an overall entry condition that offers different levels of confidence based on the user’s time devoted to the *** new entry rating system was implemented at three different mines over varying periods of time to evaluate the ground response to the geology,bolt installation pattern,stress changes by mining,overburden,and time dependency.

关键词： Coal Geology Rating system Support

Global change and biological invasions

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Journal of Plant Ecology 2022年第3期15卷 425-428页

作者： Yu-Long Feng Daolin Du mark van Kleunen Liaoning Key Laboratory for Biological Invasions and Global Changes College of Bioscience and BiotechnologyShenyang Agricultural UniversityShenyang 110866China School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang 212013China Department of Biology University of KonstanzKonstanzGermany Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation Taizhou UniversityTaizhou 318000China

Invasion by exotic species is one of the serious socio-economic,environmental and ecological problems currently faced by *** invasions have changed the species composition,structure and function of ecosystems,and are seriously threatening global biodiversity,economy and human health(Iqbal et al.2021;Wang et al.2020;Yang et al.2021;Zhao et al.2020;Zheng et al.2015).Biological invasions have resulted in an economic loss of at least US$1.288 trillion over the past few decades worldwide(Diagne et al.2021).As a consequence of these far-reaching impacts,biological invasions have become a hot research topic in modern ecology,and attract major attention from international organizations,governments and scientists all over the world.

关键词： invasion consequence

Preliminary rib support requirements for solid coal ribs using a coal pillar rib rating(CPRR)

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International Journal of Mining Science and Technology 2021年第1期31卷 15-22页

作者： Khaled Mohamed mark van Dyke Gamal Rashed Morgan MSears Robert Kimutis National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

Researchers from the National Institute for Occupational Safety and Health(NIOSH)are developing a coal pillar rib rating(CPRR)technique to measure the integrity of coal *** CPRR characterizes the rib composition and evaluates its impact on the inherent stability of the coal *** CPRR utilizes four parameters:rib homogeneity,bedding condition,face cleat orientation with respect to entry direction,and rib *** these parameters are measurable in the field.A rib data collecting procedure and a simple sheet to calculate the CPRR were *** developed CPRR can be used as a rib quality mapping tool in underground coal mines and to determine the potential of local rib instabilities and support requirements associated with overburden *** calculations were conducted for 22 surveyed solid coal ribs,mainly composed of coal *** on this study,the rib performance was classified into four categories.A preliminary minimum primary rib support density(PRSD)line was obtained from these surveyed *** sample cases are presented that illustrate the data collection form and CPRR calculations.

关键词： Coal rib stability Rib support design Coal pillar rib rating Rib quality mapping CPRR Coal classification

Evaluation of seismic potential in a longwall mine with massive sandstone roof under deep overburden

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International Journal of Mining Science and Technology 2018年第1期28卷 115-119页

作者： mark A.van Dyke Wen H.Su Joe Wickline Ground Control Branch NIOSHPittsburgh15236 PAUSA Coronado Coal LLC BeckleyWVUSA

A recent seismic event was recorded by a deep longwall mine in Virginia at 3.7 ML on the local magnitude scale and 3.4 MMS by the United States Geological Survey(USGS) in *** investigations by the National Institute for Occupational Safety and Health(NIOSH) and Coronado Coal researchers have shown that this event was associated with geological features that have also been associated with other, similar seismic events in *** mapping and geological exploration in the mining area has made it possible to forecast possible locations for future seismic *** order to use the geology as a forecaster of mining-induced seismic events and their energy potential, two primary components are *** first component is a long history of recorded seismic events with accurately plotted *** second component is a high density of geologic data within the mining *** this case, 181 events of 1.0 MLor greater were recorded by the mine's seismic network between January, 2009, and October, *** the mining area, 897 geophysical logs, 224 core holes, and 1031 fiberscope holes were examined by mine *** this information, it was found that overburden thickness, sandstone thickness, and sandstone quality contributed greatly to seismic *** the data was analyzed, a pattern became apparent indicating that the majority of seismic events occurred under specific *** forecast maps were created based on geology of previous seismic *** forecast maps have shown an accuracy of within 74%–89% when compared to the recorded 181 events that were1.0 MLor greater when considering three major geological criteria of overburden thickness of 579.12 m or greater, 6.096–12.192 m of sandstone within 15.24 m of the Pocahontas number 3 seam, and a longwall caving height of 4.572 m or less.

关键词： Seismic Mapping Deep overburden Massive sandstone

Deep cover bleeder entry performance and support loading: A case study

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International Journal of Mining Science and Technology 2018年第1期28卷 85-93页

作者： Ted M.Klemetti mark Alexander van Dyke Ihsan Berk Tulu Ground Control Branch NIOSHPittsburgh Mining Research Division Mining Engineering Department West Virginia University

Several questions have emerged in relation to deep cover bleeder entry performance and support loading:how well do current modeling procedures calculate the rear abutment extent and loading? Does an improved understanding of the rear abutment extent warrant a change in standing support in bleeder entries? To help answer these questions and to determine the current utilization of standing support in bleeder entries, four bleeder entries at varying distances from the startup room were instrumented,observed, and numerically *** paper details observations made by NIOSH researchers in the bleeder entries of a deep cover longwall panel—specifically data collected from instrumented pumpable cribs, observations of the conditions of the entries, and numerical modeling of the bleeder entries during longwall *** primary focus was on the extent and magnitude of the abutment loading experienced by the standing *** expected, the instrumentation of the standing supports showed very little loading relative to the capacity of the standing supports—less than 23 Mg load and 2.54 cm *** Flac3D program was used to evaluate these four bleeder entries using previously defined modeling and input parameter estimation *** results indicated only a minor increase in load during the extraction of the longwall *** model showed a much greater increase in stress due to the development of the gateroad and bleeder entries, with about 80% of the increase associated with development and 20% with longwall *** Flac3D model showed very good correlation between expected gateroad loading during panel extraction and that expected based on previous *** results of this study showed that the rear abutment stress experienced by this bleeder entry design was *** farther away from the startup room, the lower the applied load and smaller the convergence in the entry if all else is held ***, the numerical modeling method

关键词： Bleeder entry Standing supports Abutment loading Longwall mining Full extraction

Bleeder entry evaluation using condition mapping and numerical modeling

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International Journal of Mining Science and Technology 2021年第1期31卷 137-143页

作者： Ted M.Klemetti mark A.van Dyke Gabriel S.Esterhuizen National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

One of the most common critical areas of longwall mining in terms of ground stability are the gateroad and bleeder *** critical entries provide much-needed safe access for miners and allow for adequate ventilation required for dilution of hazardous airborne contaminants and must remain open during mining of a multi-panel *** paper is focused on the stability of the longwall entries subjected to a single abutment load such as bleeders,first tailgate,and last *** tailgate and last headgate are also referred to as blind headgate and tailgate.A study of a longwall district through conditions mapping,support evaluations,and numerical modeling was conducted and evaluated by researchers from the National Institute for Occupational Safety and Health(NIOSH).The condition mapping and support evaluations were performed on entries that spanned the previous five years of mining and relied on a diverse selection of supports to maintain the functionality of the *** modeling was also conducted to evaluate various support types with further investigation and comparison to the condition *** study demonstrated the importance of the abutment load decay versus distance from the gob edge,the potential for a reduction in material handling related injuries,as well as optimal usage of secondary and standing support.

关键词： Stability assessment Bleeder entry Abutment loading Condition mapping Longwall Ground control