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1.
Numerical modelling was done at the Cold Lake Air Weapons Range, Canada, to test whether the dissolved RDX and nitrate detected in groundwater come from the same sources, and to predict whether contamination poses a threat to the surface water receptors near the site. Military live fire training activities may indeed pose a risk of contamination to groundwater resources, however field investigations on military bases are quite recent, and little information is available on the long-term behaviour of munition residues related contaminants. Very limited information was available about the contaminant source zones, which were assigned based on our knowledge of current training activities. The RDX plume was well represented with the model, but the heterogeneous distribution of nitrate concentrations was more difficult to reproduce. It was nonetheless determined that both contaminants originate from the same areas. According to the model, both contaminants should reach the nearby river, but concentrations in the river should remain very low if the source zone concentration does not change. Finally, the model allowed the recommendation of a new location for the main bombing target, which would offer added protection to the river and the lake into which it flows.  相似文献   

2.
The gemstone cutting is a useful process to create shapes on rocks and minerals. This is done through the steps sawing, grinding, faceting and polishing, thus providing better light reflection in the pavilion with specific angles for each translucent mineral; brightness on the surface, aesthetic appreciation and their use in the jewellery industry.  相似文献   

3.
Tobacco is an important cash crop in Pakistan. It is a sensitive plant prone to many bacterial, fungal, and viral diseases. It is also attacked by several species of worms, beetles and moths. Therefore high levels of pesticides are used to grow tobacco. The obvious benefits from the use of the pesticides are so spectacular that some of the problems associated with their use are not recognized. However, many of these pesticides are highly toxic and have impacts on tobacco workers, especially occupational exposures, which are the direct victims of pesticides poisoning. The victims include many children, pregnant women and elders who all participate in tobacco production. Pesticides either cause or exacerbate a number of illnesses in farmers and farm workers when they are exposed to them. So, occupational exposure is probably one of the most important impacts on tobacco farmers, since they and their families are exposed constantly to a large amount of pesticides. This exposure can lead to many serious problems. No study has been done to identify the effects of tobacco pesticides on human health especially on farmers health in Pakistan. The objective of this paper is to establish a correlation of pesticides application on tobacco crop with cancer incidence in the tobacco growing districts of NWFP- Pakistan.  相似文献   

4.
马华东  李洪波 《新疆地质》2007,25(3):248-252
通过对新疆吐鲁番地区矿产资源特点、资源开发利用现状等问题的分析,认为吐鲁番地区矿产资源开发利用与可持续性发展目标仍有一定的差距,主要表现在矿产勘查程度低;选、冶技术水平差,以原矿产品为主,深加工程度低;粗放型经营,管理薄弱,资源利用率低;大部分小型矿山企业,无正规设计,技术落后,回采率低,资源损失和环境污染严重等.提出吐鲁番地区资源开发实现可持续性发展应从以下几方面采取措施:提高技术科技含量、加大管理制度创新、加强专业人才培养等.  相似文献   

5.
The Woolshed Creek fossil site near the Royal Military College, Duntroon, Canberra, contains brachiopods Atrypa duntroonensis (early Homerian, early Silurian, ca 430.5?Ma) within a mudstone of the Canberra Formation. Their discovery in 1844 by the Reverend William B. Clarke (“the Father of Australian Geology”), and subsequent comparison with other fossil collections from around the world, contributed significantly to the nineteenth century debate about the oldest rocks in Australia. The fossil site is now on the ACT Government Heritage List and recent site improvements make it readily accessible via a pathway from the sports grounds of the Royal Military College.  相似文献   

6.
In the prediction of ore deposits, a series of geological, geochemical, and geophysical characters are used to describe the model of ore deposits. The problem is how to use the characters of known ore deposits to establish the model and to look for the target areas with similar geological environments. This can be done with a powerful mathematical tool—discriminant analysis. Nevertheless, there generally are too many geological variables to describe a class of ore deposits. Some of them are discrete, and the others are continuous. It is also difficult to know their distributions. A satisfactory method of discrimination has not been developed for such a complicated case. For this reason, we introduce a new method of orthogonally stepwise discrimination. We used this method to predict copper ore deposits of Dongchuan type in central Yunnan, China, with satisfactory results.  相似文献   

7.
Gulati  Sneh  Sampson  Charles R. 《Natural Hazards》2021,108(2):1687-1700
Natural Hazards - U. S. Military bases are especially vulnerable to tropical cyclones (TCs) because they concentrate extremely expensive equipment in a small area. A TC hit at a base can result in...  相似文献   

8.
Specialized cosmetic products for infant use are gaining a lot of popularity in the Indian as well as global market, as these products have become an inseparable part of modern urban lifestyle. Baby cosmetics are available in a wide range. They claim to be milder than similar products meant for adult use. However, these products need to be checked for their safety through a battery of assays based on biological systems, along with the ones based on chemical and physical protocols. This study attempts to test different baby cosmetic products using one prokaryotic and one eukaryotic assay system. Chemical protocols prescribed by cosmetic product controlling organizations of India are also used to estimate the quantity of harmful heavy metals like arsenic, lead and cadmium if present in the samples. Few of the products tested have shown significant toxicity as well as heavy metal content. The results hold a lot of importance keeping in mind the extra sensitivity of an infant body. It is further suggested that studies using cell based and in vivo test systems should be done to confirm the findings.  相似文献   

9.
Finding which triangle in a planar or 2.5D triangle mesh contains a query point (so-called point location problem) is a frequent task in geosciences, especially when working with triangulated irregular network models. Usually, a large number of point locations has to be performed, and so there is a need for fast algorithms having minimal additional memory requirements and resistant to changes in the triangulation. So-called walking algorithms offer low complexity, easy implementation, and negligible additional memory requirements, which makes them suitable for such applications. In this article, we focus on these algorithms, summarize, and compare them with regard to their use in geosciences. Since such a summary has not been done yet, our article should serve those who are dealing with this problem in their application to decide which algorithm would be the best for their solution. Moreover, the influence of the triangulation type on the number of the visited triangles is discussed.  相似文献   

10.
为了进一步拓展地质学的研究和应用领域,促进现代军事科学技术与地质学的融合发展,通过梳理总结军事地质发展简史,结合现代高技术战争特点,探索性地提出了“军事遥感地质学”这一学科概念,初步定义了军事遥感地质学的内涵与外延,探讨了学科的研究方法和工作任务,并对未来学科建设提出了一些建议和设想。  相似文献   

11.
长江三峡工程库区巴东新城址环境工程地质预测   总被引:2,自引:0,他引:2  
巴东县城新址是长江三峡工程库区移民城镇环境工程地质问题较突出的场址之一, 主要环境工程地质问题是古滑坡的失稳和库岸再造。在查清地质环境条件的基础上, 本文着重进行了黄土坡古滑坡、赵树岭古滑坡等古滑坡的稳定性预测, 并根据实测的有关参数, 采用图解法预测库岸再造宽度。在此基础上, 根据影响该区城市开发建设的主要的地质环境要素, 建立隶属函数, 采用模糊综合评判模型及算法, 给出巴东县城新址区的城市开发建设的环境地质分区评价。  相似文献   

12.
Monitoring Forest Fire Danger with Remote Sensing   总被引:2,自引:2,他引:0  
Our paper presents a review of the use of remote sensing technologies for forest wildfire danger monitoring, with a particular emphasis on its applicability to fuel moisture monitoring. Remote sensing of fuel moisture was first done with NOAA-AVHRR NDVI images, but NDVI is more related to vegetation greenness rather than water stress. NOAA-AVHRR surface temperature images were also used, alone or in association with NDVI images. Both kinds of images have a limited image availability due to cloud cover. This is not the case for radar images, but their use in fuel moisture monitoring is still experimental, because of the noisy effects of several factors. Finally, the paper discusses the operational potentials and limitations of the use of each kind of satellite data for fire danger monitoring.  相似文献   

13.
The South African mining industry first experienced en-masse use of electronic detonators in the Narrow Reef environment using AEL's Electrodet™ pre-set delay system. In recent years, programmable systems such as AEL's Smartdet™ have also established their position, and within both AEL and the mines there has been important learning around the strengths and weaknesses of these systems. In general, the fixed delay systems tend to be more easily appreciated by less-skilled work teams, and are very well suited to simple layouts, especially long, narrow blasts. However, development of programmable row controllers and series delay inserts has greatly expanded the field of usefulness of these systems while retaining most of the simplicity of use. The programmable systems are immensely flexible and therefore able to function under any condition, but require a higher level of discipline and knowledge. Much has been done to address this issue and make the systems user friendly, so the systems have converged to some extent. These systems are both valuable tools for achieving control over blasting in underground and surface applications. The choice of system is very dependent on the prevailing conditions. Accurate timing with electronic enhancements continues to show an increasing range of benefits to mining operations. There is a strong parallel with non-electronic initiation systems which helps to understand the appropriate use of the systems.  相似文献   

14.
北京和深圳城市化比较研究   总被引:28,自引:0,他引:28  
通过对北京和深圳两个城市的城市化过程的比较研究,得出北京经历了一个稳定的城市化发展过程,城市人口(以户籍人口为主)城市化水平与人均国内生产总值的对数成正比关系,城市以"摊大饼"的模式向外扩张以及城市环境问题主要为大气污染和水资源匮乏;深圳经历了一个快速的城市化过程,城市人口以外来人口为主,城市化水平与人均国内生产总值成三次关系,城市沿交通干线向外扩张及城市环境问题主要是水污染和水土流失。两个城市化过程的差异主要是由于两个城市的政策和经济相互作用方式不同。  相似文献   

15.
常学向  赵文智 《冰川冻土》2009,31(6):1201-1210
树木水分利用的研究总体上可分为三个尺度, 即叶片、林木和林分尺度. 近年来, 林木水分利用的定量研究显得日益重要, 森林生理学和森林水文学的发展以及应用都与林木水分利用的定量研究密不可分. 对国内外近年来林木尺度水分利用研究的方法、 研究进展及存在的问题进行了详细的阐述, 提出了今后林木水分利用定量研究需开展的重点工作, 以期促进林木水分利用定量研究的进一步发展.  相似文献   

16.
Environmental considerations in the fertilizer use decision   总被引:1,自引:0,他引:1  
 The increase in the use of fertilizer in agricultural production has been associated with a substantial increase in agricultural productivity in the United States. This increase in fertilizer use has been driven by a variety of economic forces including variations in the price of output and changing relative factor prices. Associated with the increase in the use of fertilizer have been adverse environmental consequences that are not reflected in the costs and returns of agricultural production. That is, externalities exist whose cost need to be internalized. Because the use of fertilizer has been shown to respond to market forces, it is efficient to use the market to control the use of fertilizer. This can be done through, for example, the use of a fertilizer tax. Received: 31 December 1996 · Accepted: 13 May 1997  相似文献   

17.
He  Yutong  Bai  Yang  Tian  Di  Yao  Li  Fan  Runlong  Chen  Pengfei 《中国地球化学学报》2019,38(5):718-733

Geoanalytical data provide fundamental information according to which the Earth’s resources can be known and exploited to support human life and development. Large amounts of manpower and material and financial resources have been invested to acquire a wealth of geoanalytical data over the past 40 years. However, these data are usually managed by individual researchers and are preserved in an ad hoc manner without metadata that provide the necessary context for interpretation and data integration requirements. In this scenario, fewer data, except for published data, can be reutilized by geological researchers. Many geoanalytical databases have been constructed to collect existing data and to facilitate their use. These databases are useful tools for preserving, managing, and sharing data for geological research, and provide various data repositories to support geological studies. Since these databases are dispersed and diverse, it is difficult for researchers to make full use of them. This contribution provides an introduction on available geoanalytical databases. The database content can be made accessible to researchers, the ways in which this can be done, and the functionalities that can be used are illustrated in detail. Moreover, constraints that have limited the reutilization of geoanalytical data and creation of more advanced geoanalytical databases are discussed.

  相似文献   

18.
The spatial resolution of digital elevation models (DEMs) is an important factor for reliable landslide studies. Multi-interferometric techniques such as persistent scatterer interferometric synthetic aperture radar (PSInSAR) are used to evaluate the landslide state of activity and its ground deformation velocity, which is commonly measured along the satellite line of sight (LOS). In order to compare velocities measured by different satellites in different periods, their values can be projected along the steepest slope direction, which is the most probable direction of real movement. In order to achieve this result, DEM-derived products are needed. In this paper, the effectiveness of different DEM resolutions was evaluated in order to project ground deformation velocities measured by means of PSInSAR technique in two different case studies in the Messina Province (Sicily, southern Italy): San Fratello and Giampilieri. Three DEMs were used: (i) a 20-m resolution DEM of the Italian Military Geographic Institute (IGM), (ii) a 2-m resolution DEM derived from airborne laser scanning (ALS) light detection and ranging (LiDAR) data for the San Fratello 2010 landslide, and (iii) a 1-m resolution DEM derived from ALS LiDAR data for the area of Giampilieri. The evaluation of the applied method effectiveness was performed by comparing the DEMs elevation with those of each single permanent scatterer (PS) and projecting the measured velocities along the steepest slope direction. Results highlight that the higher DEM resolution is more suitable for this type of analysis; in particular, the PS located nearby the watershed divides is affected by geometrical problems when their velocities are projected along the steepest slope.  相似文献   

19.
This paper reports the results of a Bayesian-based algorithm for the retrieval of hydrometeors from microwave satellite radiances. The retrieval technique proposed makes use of an indigenously developed polarized radiative transfer (RT) model that drives a data driven optimization engine (Bayesian) to perform retrievals of rain and other hydrometeors in a multi-layer, plane parallel raining atmosphere. For the sake of completeness and for the purposes of comparison, retrievals with Artificial Neural Networks (ANN) have also been done. Retrievals have been done first with a simplified two-layer atmosphere, where assumed values of hydrometeors are given to the forward model and these are taken as ‘measured radiances’. The efficacy of the two retrieval strategies is then tested for this case in order to establish accuracy and speed. The highlight of the work is however, the case study wherein a tropical storm in the Bay of Bengal is taken up, to critically examine the performance of the retrieval algorithm for an extreme event wherein a 14-layer realistic, raining atmosphere has been considered and retrievals are done against Tropical Rainfall Measuring Mission (TRMM) measured radiances. The key novelties of the work are:
–  inclusion of polarization from both hydrometeors and oceans in the RT model, and  相似文献   

20.
在公路拓宽过程中,由于沉降、变形累积和稳定性的差异,在新旧路基之间产生差异沉降,进而会引起原有路基变形,新路基失稳,甚至出现路基拉裂和下沉坍塌病害。以某山区拓宽公路中一段病害路基为例,在调查其病害特征的基础上,分析其形成机理,提出防治方法。  相似文献   

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