隧道含水断层破碎带的探测

以泉三高速公路某隧道含水断层为例,对比瑞利波和地质雷达两种探测技术,论述其优缺点,阐明瑞利波探测技术探测公路施工隧道含水断层破碎带的优点。     

覆岩采动裂隙带发育规律的数值模拟分析

运用FLAC-3D数值模拟软件,对特定开采条件下覆岩破坏发育规律进行分析.通过现场实测,获取基础数据.建立合理的数学模型,对实测数据进行反演计算.数值模拟分析获得的结果准确可靠,可以预计类似条件下的覆岩采动裂隙带发育高度.     

山东沂南金矿床成矿物质来源探讨

矿床宏观特征、矿体产出状态、围岩蚀变、矿石组构及矿物组合特征等,均清楚表明沂南金矿床是一个典型的夕卡岩型矿床。本文通过对矿床铅、硫、碳、氧、氢等同位素特征的研究,探讨了成矿物质来源。矿石铅同位素组成显示异常铅特征,在连续增长模式下,放射性铅同位素源区年龄为2390Ma,与区域花岗-绿岩带固结时间相当。μ值介于9.56～12.17之间,显示金属成矿元素主要源自地壳,少量来自地幔。Th/U值集中在3.30～3.62之间,接近于上地壳Th/U值,表明晚太古代晚期～早元古代壳-幔相互作用形成的花岗-绿岩带(泰山群)是沂南金矿床的主要矿源层。硫、碳同位素特征表明矿石中的硫和碳主要源自深源岩浆。氢、氧同位素组成显示成矿流体主要为岩浆热液,在成矿晚期有不同程度的大气降水混入。     

基于气味探测技术的矿井输送机胶带火灾监测

将气味探测技术应用于矿井输送机胶带火灾监测,以较早、准确地探测胶带火灾.煤、橡胶、机油是煤矿井下引发胶带火灾的3种主要可燃物质,气味传感器对这3种物质的受热响应实验表明,气味传感器可以在相对于火灾发生时较低的温度下监测到煤(50℃)、橡胶(65℃)、机油(110℃)受热产生的气味,并以不同温度下传感器的输出变化值(即巷道的气味变化)来判断是否发生了火灾.研究了气味传感器在井下的布置方式,认为气味传感器宜布置在气味浓度较高的混合浓度区,并通过相似理论模拟得出其间距L.     

一起带状屑割伤车工双腿事故的原因及预防措施

利用安全系统工程学中事故树分析法对带状屑割伤车工双腿事故进行了分析 ,并提出了防止事故发生的预防措施。     

青藏高原东部亚高山森林草甸植被地理格局的成因探讨

森林和草地在亚高山带的阴阳坡上形成的交错分布现象,呈一弧型分布在青藏高原东部本文在综合分析了造成这种现象的生理生态因素之后,重点从火的作用、放牧作用和历史时期人类活动的影响等方面,讨论了青藏高原东部亚高山带植被地理格局的形成原因结果表明,自然生态因素和人类活动的影响在植被地理格局的形成过程中起着同等重要的作用,其中火灾的作用以及气候变化造成的人口迁移压力作用十分明显．在这一弧形区域内,林线以下的亚高山灌丛或草甸多属次生类型,人类有目的的烧荒和长期放牧阻滞了植被的顺向演替,维持了亚高山（灌丛）草甸的偏途顶级状态．     

Arsenic in North Carolina: public health implications

Arsenic is a known human carcinogen and relevant environmental contaminant in drinking water systems. We set out to comprehensively examine statewide arsenic trends and identify areas of public health concern. Specifically, arsenic trends in North Carolina private wells were evaluated over an eleven-year period using the North Carolina Department of Health and Human Services database for private domestic well waters. We geocoded over 63,000 domestic well measurements by applying a novel geocoding algorithm and error validation scheme. Arsenic measurements and geographical coordinates for database entries were mapped using Geographic Information System techniques. Furthermore, we employed a Bayesian Maximum Entropy (BME) geostatistical framework, which accounts for geocoding error to better estimate arsenic values across the state and identify trends for unmonitored locations. Of the approximately 63,000 monitored wells, 7712 showed detectable arsenic concentrations that ranged between 1 and 806 μg/L. Additionally, 1436 well samples exceeded the EPA drinking water standard. We reveal counties of concern and demonstrate a historical pattern of elevated arsenic in some counties, particularly those located along the Carolina terrane (Carolina slate belt). We analyzed these data in the context of populations using private well water and identify counties for targeted monitoring, such as Stanly and Union Counties. By spatiotemporally mapping these data, our BME estimate revealed arsenic trends at unmonitored locations within counties and better predicted well concentrations when compared to the classical kriging method. This study reveals relevant information on the location of arsenic-contaminated private domestic wells in North Carolina and indicates potential areas at increased risk for adverse health outcomes.     

乌东德水库坝前段消落带生态类型划分及生态修复模式初探

采用GIS技术,根据高程、坡度、土壤类型等环境特征,将乌东德水库坝前段消落带分为18种生态类型,并完成了高程图、坡度图和土壤类型图,建立了环境特征和消落带类型的直观联系。然后根据不同的生态类型,提出了4种生态修复模式,并选择了10种植物作为生态修复物种。为其它水库消落带生态修复提供了参考依据。     

长江口港口群建设条件与布局

和茳口港口群指以上海港为中心，分南北翼的杭州湾地区与苏北沿海地带以及以长江为中轴的各类港口所组成的组合式港口。它们可以充分利用江海水域资源，建设各类不同层次，不同规模的大中小结合、综合性港与专业性港相配套的港口群体。同时，可以发挥两省一市的积极性，多快好省地建设上海国际航运中心。     

Numerical and experimental study on flame spread over conveyor belts in a large-scale tunnel

Conveyor belt fires in an underground mine pose a serious life threat to the miners. This paper presents numerical and experimental results characterizing a conveyor belt fire in a large-scale tunnel. A computational fluid dynamics (CFD) model was developed to simulate the flame spread over the conveyor belt in a mine entry. Thermogravimetric analysis (TGA) tests were conducted for the conveyor belt and results were used to estimate the kinetic properties for modeling the pyrolysis process of the conveyor belt burning. The CFD model was calibrated using results from the large-scale conveyor belt fire experiments. The comparison between simulation and test results shows that the CFD model is able to capture the major features of the flame spread over the conveyor belt. The predicted maximum heat release rate, and maximum smoke temperature are in good agreement with the large-scale tunnel fire test results. The calibrated CFD model can be used to predict the flame spread over a conveyor belt in a mine entry under different physical conditions and ventilation parameters to aid in the design of improved fire detection and suppression systems, mine rescue, and mine emergency planning.