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51.
绿色矿山建设是矿业健康持续发展的时代要求,是矿产资源管理制度改革发展的重要方向,是建设生态文明、矿业转型升级的必然选择,是山东省矿业发展的必由之路。该文重点论述绿色矿山的内涵、基本条件、重要意义,分析了山东省绿色矿山建设面临的数量偏少、地方标准不健全、各职能部门协同机制有待进一步完善等多方面问题。并在此基础上,提出下步山东省绿色矿山建设的几点建议,包括严格规划管控、坚持试点引路及推进标杆企业建设、加快标准制定及出台相关管理办法、积极推动绿色矿业发展示范区建设等多项建议。  相似文献   
52.
安徽宣城地区上二叠统龙潭组海陆过渡相页岩不仅是我国下扬子区重要的烃源岩,也是目前我国页岩气勘探的重要层位之一.为研究海陆过渡相页岩沉积环境与有机质富集的关系,以港地1井和两个露头剖面为研究对象,系统开展了有机地球化学测试、有机岩石学研究、氩离子抛光—扫面电镜观察、元素地球化学分析等工作.结果表明:下扬子宣城地区龙潭组页...  相似文献   
53.
As a cold and dry planet, Mars contains water resources in the form of water ice, so that the electromagnetic waves can be transmitted to the deep underground to get the information of the topography and subsurface geological structure. Subsurface penetrating radar(SPR) can be widely used in deep space exploration for a long time because of its non-destructive detection mode and its working characteristics not limited by visible light. It is an important type of equipment for detecting the subsurface structure of planets. Orbiter radar is mainly used in Mars exploration. However, because of its low resolution, it is difficult to describe the near surface structure, so there is a lack of radar data which can reflect the shallow information. In this paper, a three-dimensional near surface model of Utopia Planitia on Mars is established. In order to make the simulation results more reasonable, the key factors such as topographic relief, subsurface rocks and water ice, and the variation of dielectric constant in different layers are taken into account. Then the full polarization forward modeling is carried out by using the three-dimensional finite-difference time-domain method. The acquired full polarimetric subsurface penetrating radar(FP-SPR) data with noise is preprocessed and further processed by Pauli decomposition. The underground reflection can be picked up more clearly from the Pauli decomposition results. This work is helpful to identify more details of subsurface structures and provides a reference for the measured data in the future.  相似文献   
54.
This study conducted microtremor testing along six survey lines that cross three typical earth fissures in the Datong basin to determine the dynamic response characteristics of earth fissure sites with regard to the Fourier amplitude spectrum, response spectrum, and Arias intensity. The results show the following.(1) The predominant frequency of an earth fissure site is mainly affected by the thickness and the shear wave velocity of the soil layer and is minimally effected by the presence of an earth fissure.(2) Earth fissures have a pronounced amplification effect on dynamic response. Fourier amplitude, response acceleration, and Arias intensity are high near an earth fissure and decrease with an increase in distance from the earth fissure, tending toward stability at a distance of 20 m.(3) The area that is seriously affected by this amplification is within 6–8 m of an earth fissure, and the general affected area is farther out than this, to a distance of 25 m.(4) New construction should be avoided in an area affected by the amplification, and existing buildings in general and seriously affected areas need to be reinforced to increase their seismic fortification intensity.  相似文献   
55.
以漳江口国家级红树林自然保护区、九龙江口省级红树林自然保护区和泉州湾省级湿地保护区3个红树林分布区作为研究对象,研究底栖软体动物在中等尺度下的共存格局及机制。利用非度量多维标度分析、基于蒙特卡洛的零模型和网络分析探讨底栖软体动物的共存格局,利用raup-crik零模型识别决定性过程和随机过程测定底栖软体动物的相对重要性。结果显示,漳江口、九龙江口和泉州湾湿地共发现37种底栖软体动物,底栖软体动物的平均密度、物种数及群落物种组成差异显著。软体动物的共存格局呈现非随机分散和模块化,这些格局同时受到决定性过程和随机过程的调控作用,其中,物种竞争起主导作用。  相似文献   
56.
基于河南省111个气象站1961—2017年均一化前后逐日平均气温数据,采用统计分析方法,分析均一化前后河南省年、四季和月的平均气温变化规律及其空间分布,以期明确非自然因素对河南省平均气温变化趋势的影响.结果表明:1961—2017年,均一化前后河南省年平均气温均呈显著上升,均一化后增温速率为0.21℃/10 a,较均...  相似文献   
57.
由于丰富的煤炭资源,内蒙古的下白垩统地层具有重要的经济价值.但长期以来相关地层一直缺乏同位素测年研究,影响了区域地层对比工作的开展.本文对内蒙古锡林浩特下白垩统胜利组煤层夹层中的火山灰锆石应用LA-ICP-MS进行U-Pb法测年,结果显示胜利组5煤(层)和6煤(层)形成于大约109-107 Ma(早白垩世阿尔布期).这...  相似文献   
58.
旅游是一种特殊的文化交流活动,在跨文化交际中常常会发生文化冲突,这大多是由于不同文化之间的差异造成的.中西文化差异导致旅游跨文化交际障碍的因素很多,其中最重要的因素是中西方价值取向、思维方式、行为规范的差异.在旅游跨文化交际中应特别增加中西文化差异意识,方能尽量减少交际障碍.  相似文献   
59.
为了解象山近岸海域水质污染状况,文章根据2012—2016年象山县近岸海域的水质监测结果,分析象山近岸海域水质现状及年际变化。应用灰色预测的模型来对象山近岸海域水质主要污染物的相关数据进行处理,得出主要污染物的预测结果。分析结果表明:象山近岸海域主要污染物为无机氮。用预测结果和实际数值通过残差验证,最后模拟出今后几年的监测值,为象山县近岸海域生态环境相关管理部门提供数据支撑和决策依据。  相似文献   
60.
Based on statistical data and population flow data for 2016,and using entropy weight TOPSIS and the obstacle degree model,the centrality of cities in the Yangtze River Economic Belt(YREB)together with the factors influencing centrality were measured.In addition,data for the population flow were used to analyze the relationships between cities and to verify centrality.The results showed that:(1)The pattern of centrality conforms closely to the pole-axis theory and the central geography theory.Two axes,corresponding to the Yangtze River and the Shanghai-Kunming railway line,interconnect cities of different classes.On the whole,the downstream cities have higher centrality,well-defined gradients and better development of city infrastructure compared with cities in the middle and upper reaches.(2)The economic scale and size of the population play a fundamental role in the centrality of cities,and other factors reflect differences due to different city classes.For most of the coastal cities or the capital cities in the central and western regions,factors that require long-term development such as industrial facilities,consumption,research and education provide the main competitive advantages.For cities that are lagging behind in development,transportation facilities,construction of infrastructure and fixed asset investment have become the main methods to achieve development and enhance competitiveness.(3)The mobility of city populations has a significant correlation with the centrality score,the correlation coefficients for the relationships between population mobility and centrality are all greater than 0.86(P<0.01).The population flow is mainly between high-class cities,or high-class and low-class cities,reflecting the high centrality and huge radiating effects of high-class cities.Furthermore,the cities in the YREB are closely linked to Guangdong and Beijing,reflecting the dominant economic status of Guangdong with its geographical proximity to the YREB and Beijing's enormous influence as the national political and cultural center,respectively.  相似文献   
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