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1.
Professor Emerita Valerie Hall died on 28th July, 2016, in Belfast City Hospital after a long battle with cancer. Valerie was a renowned and highly esteemed inter-disciplinarian, who began her career in botany and palynology but made a truly international mark in the field of cryptotephrochronology. Between us, we knew her as a student, a supervisor, an examiner, a mentor, a colleague, a role model, and, above all, a wonderful, kind-hearted and generous friend. She touched the hearts and earned the respect of Quaternary scientists around the world. Here, to honour her memory, we reflect briefly on the great woman and scientist that she was.  相似文献   

2.
The importance of obtaining depth-specific ground water samples is now well recognized among practitioners and scientists alike. Many methods and technologies are available for level discrete or depth-specific ground water sampling in consolidated aquifers. All methods have their associated advantages and drawbacks, however. One common disadvantage is that they are expensive. A large number of point discrete ground water samples were required for a UK research project aimed at quantifying natural attenuation processes in ground water contaminated by a former coal carbonization plant. Based on experience from a previous project to develop novel level accurate sampling methodologies for use in existing boreholes, the Ground Water Protection and Restoration Research Unit (GWPRRU) produced and tested a low-cost design multiport sock sampler for ground water monitoring. The sock sampler design allowed the recovery of multiple depth-specific ground water samples from depths of 150 feel (45 m) from individual boreholes in the sandstone aquifer at the field site. Because of their use of inexpensive materials, simple design, installation and use that does not require gravel packs, packers, or grouting, sock samplers were found to be the most cost effective, convenient, and reliable method of obtaining multiple depth-specific ground water samples at the project field site.  相似文献   

3.
Anthrax. The word conjures images of germ warfare, which is pretty ridiculous when you discover that we're not really sure anthrax has ever been used in this fashion. Germ warfare is certainly not what came to mind when a six-year-old girl showed up in our clinic with half of her face puffed up like a balloon, her right eye swollen shut (Figure 1). We were in rural Haiti, where a very different sort of germ warfare is the rule. So what came to mind that day was the word epidemic, and sure enough a young woman from the same village was also diagnosed with cutaneous anthrax—called charbon in Haiti, "malignant pustule" in the older textbooks—on her right chest wall. Soon after their arrival, both were receiving intravenous penicillin; they would recover completely. Later that night, the clinic's medical staff held a meeting. Another anthrax case had been diagnosed a few days earlier, and the patient was from the same area. It seemed increasingly likely that we were dealing with an epidemic. By morning, we learned that a young man from the village had just died of charbon. Why? "Because he didn't have enough money to get here." It costs no more than four dollars to take a truck from their village to our clinic. It was an epidemic, all right, and it had already taken a life.  相似文献   

4.
Designation and Assessment of Artificial and Heavily Modified Water Bodies under the EC Water Framework Directive The EC Water Framework Directive allows the Member States to designate artificial and heavily modified water bodies under specific conditions. For those water bodies the ecological assessment and the resulting programmes of measures will be based on the “maximum ecological potential” as reference conditions and not on the “high ecological status”, which has to be used for natural water bodies. Such designation is possible only, if the hydromorphology of the water bodies concerned has been substantially changed in character to maintain specified uses. The criteria for the designation are fulfilled, if restoration measures needed to meet the high ecological status would have significant adverse effects on the uses and if no other better environmental options would exist to maintain the specified uses. In late 1999 the EC‐Working Group on Heavily Modified Water Bodies (HMWB) has been established to develop criteria for the designation of artificial and heavily modified water bodies as well as for the determination of the maximum ecological potential. The working group has produced the guidance document “Identification and Designation of Artificial and Heavily Modified Water Bodies” in November 2002, which has been agreed by the European Water Directors on 21 November 2002 in Copenhagen. The guidance document is focusing on two time borders, the provisional identification of heavily modified water bodies until 2004 and the legally binding designation as artificial and heavily modified in the first river basin management plan in 2009 at the latest. The guidance document considered the main findings of 34 case studies for rivers, lakes, transitional and coastal waters carried out in 11 European countries. The results of the case studies as well as a summarizing synthesis were used as a fundamental basis to produce the guidance document. The practical examples given by the case studies were compiled as a toolbox which supplements the guidance for the purpose of its better application.  相似文献   

5.
In 1992, the U.S. Environmental Protection Agency (EPA) proposed risk-based management of hazardous waste. A major component of the proposed rule is the determination of non-site- specific screening concentration levels from waste leachate. Ground water at a downgradient exposure point must not exceed those screening levels, or more stringent requirements would apply.
The screening concentration level is determined with verified models and equations that simulate the transport and attenuation of chemicals as they travel from the source area to the exposure point. A consortium of screening levels is determined in this paper by considering varying physical, chemical, and biological conditions. In addition, a method is developed for multi component leaching from contaminated soils in a landfill to determine the time-dependent behavior of a finite source. Finally, this paper discusses infiltration rate through the clay liner.  相似文献   

6.
Abstract. Although Georgia receives approximately 50 inches of precipitation annually, concern over water quantity is increasing in this State. Historically, ground-water problems were associated with major urban-industrial withdrawals but recent irrigation development in the southwestern portion of the State has attracted attention. Irrigation withdrawals were exempted from the permit requirements of the 1972 Ground Water Use Act. This has led to an inability to manage the resource and questions regarding legal rights to the use of water. Current activities in the State indicate that measures may be taken during the 1980 session of the Georgia General Assembly to enable better management of the State's water resources.  相似文献   

7.
A retrospective review of the current scientific publications on the problems of water protection zones at water bodies is given. The content of regulations on water protection zone in the RF Water Code 2006 now in force is interpreted. The legislations regarding the establishment of water protection zones and riparian buffer strips at water bodies in Russia and other countries are compared and analyzed. The technologies and specifics of the development of geoinformation system “Water Protection Zone and Riparian Buffer Strip of a Water Body” are demonstrated as applied to determining the boundary of the water protection zone and riparian buffer strip for the Uglich Reservoir. Assessment of the anthropogenic load onto a drainage basin within the water protection zone of the Uglich Reservoir and a method for geoecological zoning of its territory are considered as an example.  相似文献   

8.
《Astronomy& Geophysics》2009,50(1):1.15-1.17
Lucinda Douglas-Menzies is a fine-art photographer. More than 70 of her portraits are owned by the National Portrait Gallery, including 10 from her latest exhibition "Portraits of Astronomers", which will tour the UK during IYA2009. Here she explains why she chose astronomers.  相似文献   

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Li SG  Liu Q 《Ground water》2006,44(5):758-763
We present in this note an innovative software environment, called Interactive Ground Water (IGW), for unified deterministic and stochastic ground water modeling. Based on efficient computational algorithms, IGW allows simulating three-dimensional (3D) unsteady flow and transport in saturated media subject to systematic and "random" stresses and geological and chemical heterogeneity. Adopting a new computing paradigm, IGW eliminates the fragmentation in the traditional modeling schemes and allows fully utilizing today's dramatically increased computing power. For many problems, IGW enables real-time modeling, visualization, mapping, and analysis. The software environment functions as a "numerical laboratory" in which an investigator may freely explore the following: creating visually an aquifer system of desired configurations, interactively applying stresses and boundary conditions, and then investigating and visualizing on the fly the geology and flow and transport dynamics. At any time, a researcher can pause to interact dynamically with virtually any aspects of the modeling process and then resume the integrated visual exploration; he or she can initiate, pause, or resume particle tracking, plume modeling, subscale modeling, stochastic modeling, monitoring, and budget analyses. IGW continually provides results that are dynamically processed, overlaid, and displayed. It dynamically merges modeling inputs and outputs into composite two-dimensional/3D images-integrating related data to provide a more complete view of the complex interplay among the geology, hydrology, flow system, and transport. These unique capabilities of real-time modeling, steering, analysis, and mapping expand the utility of models as tools for research, education, and professional investigations.  相似文献   

13.
以新一轮国土资源大调查“柴达木盆地地下水资源及其环境问题调查评价”项目为依托,围绕时序预测建模软件(Time Series Forecast V1.0)的研发与应用,按照现代预测学理论对柴达木盆地的水文、气象等多因子时序量进行了百年预测。针对多因子综合评价模型提出并采用了先进可行的“主成分”分析法,建立了“特征向量”与“综合指标”的对等关系,从而避免了以往诸多评价模型中人为因素的干扰,提高了预测结果的可信度。  相似文献   

14.
Having immediate, automated field access to data gathered during geological and hydrogeological investigations can be crucial to definition of the scope and direction of test procedures, as well as to the interpretability of results. A portable, briefcase-sized data collection and analysis instrument has therefore recently been developed. It is capable of operating as a standalone or operator-guided field unit. This terminal is pre-programmed for a number of standard applications, several of which involve BAT® tools, e.g., permeability tests made using the BAT Ground Water Monitoring System. It can, however, be used with a wide range of other tools for controlling data collection during pumping, penetration and pressometer tests, etc.
An operator's terminal and independent data collection microcontroller are the major components of this system. Data may be collected from any combination of four ports: an internal, programmable interval timer, a pulser (shaft encoder), and two 14-bit analog-to-digital (A/D) inputs. The latter are primarily used for pressure or resistance transducers. Reading of data may be triggered automatically by the timer and/or pulser, or be performed upon operator command. Many thousands of data points may be stored in the microcontroller, representing one or several tests of any type, intermixed. Via the operator's terminal, any subset of this stored data may be examined, erased, modified or analyzed. A 26-character LCD display and a four-color printer/plotter are used to record data and results of analyses. Data may also be transferred to an external computer for more extensive manipulation.
Three examples of how this terminal may be used in the field in connection with site investigations are presented in this paper. They involve (a) measurement of saturated hydraulic conductivity, (b) determination of soil stratigraphy using pore pressure sounding, and (c) water network profiling.  相似文献   

15.
A major portion of the work effort and, therefore, the money spent during investigations of ground water and the vadose zone at hazardous waste sites is associated with collecting chemical data. To that end, effective decontamination of reusable drilling equipment, sampling apparatus, and tools is critical to the credibility of chemical data. Samples representative of the site under study are essential.
Several state and federal regulatory agencies have established guidelines for procedures that should be considered when developing decontamination protocols. These agencies were contacted and asked to furnish copies of their decontamination guidelines. The information received was reviewed, and comparisons were made to assess the status of standards of decontamination practices for ground water and vadose zone monitoring programs at hazardous waste sites. Summaries of a variety of decontamination protocols were prepared. From this review, it is apparent that there is a need to standardize, to the extent possible, procedures for the field decontamination of equipment.
Two ASTM Subcommittees, D18.14 on Waste Management and D18.21 on Ground Water and Vadose Zone Monitoring, are currently working on developing standards for decontamination procedures. They, in cooperation with state and federal agencies and other interested technical groups, will develop standards for the field decontamination of equipment used to study ground water and the vadose zone.  相似文献   

16.
Update on the use of the RORA program for recharge estimation   总被引:5,自引:2,他引:3  
Rutledge AT 《Ground water》2007,45(3):374-382
  相似文献   

17.
The role of ground water in arid/semiarid ecosystems, Northwest China   总被引:3,自引:0,他引:3  
Cui Y  Shao J 《Ground water》2005,43(4):471-477
Ground water plays an important role in water supply and the ecology of arid to semiarid areas such as Northwest China, where the landscape is fragile due to frequent drought in the past few decades. This paper discusses the role of ground water in these ecosystems, including the effect of condensation water and water table depth on the growth of plants and degree of soil salinity. The paper also discusses the controlling process for land desertification and soil salinization in Northwest China. Water table depth is a key factor controlling the water balance, ground water flow, and salt transport in the vadose zone. The suitable water table depth for vegetation growth, which can prevent land desertification and soil salinization, is within a range of 2 to 4 m; the optimal depth is approximately 3 m. As examples, changes in ecosystems owing to water resources development in Tarim and Manas basins, Xinjiang, China, are discussed.  相似文献   

18.
Strong motion recordings are the key in many earthquake engineering applications and are also fundamental for seismic design. The present study focuses on the automated correction of accelerograms, analog and digital. The main feature of the proposed algorithm is the automatic selection for the cut-off frequencies based on a minimum spectral value in a predefined frequency bandwidth, instead of the typical signal-to-noise approach. The algorithm follows the basic steps of the correction procedure (instrument correction, baseline correction and appropriate filtering). Besides the corrected time histories, Peak Ground Acceleration, Peak Ground Velocity, Peak Ground Displacement values and the corrected Fourier Spectra are also calculated as well as the response spectra. The algorithm is written in Matlab environment, is fast enough and can be used for batch processing or in real-time applications. In addition, the possibility to also perform a signal-to-noise ratio is added as well as to perform causal or acausal filtering. The algorithm has been tested in six significant earthquakes (Kozani-Grevena 1995, Aigio 1995, Athens 1999, Lefkada 2003 and Kefalonia 2014) of the Greek territory with analog and digital accelerograms.  相似文献   

19.
<正>Ground motion records are often used to develop ground motion prediction equations(GMPEs) for a randomly oriented horizontal component,and to assess the principal directions of ground motions based on the Arias intensity tensor or the orientation of the major response axis.The former is needed for seismic hazard assessment,whereas the latter can be important for assessing structural responses under multi-directional excitations.However,a comprehensive investigation of the pseudo-spectral acceleration(PSA) and of GMPEs conditioned on different axes is currently lacking.This study investigates the principal directions of strong ground motions and their relation to the orientation of the major response axis, statistics of the PSA along the principal directions on the horizontal plane,and correlation of the PSA along the principal directions on the horizontal plane.For these,three sets of strong ground motion records,including intraplate California earthquakes,inslab Mexican earthquakes,and interface Mexican earthquakes,are used.The results indicate that one of the principal directions could be considered as quasi-vertical.By focusing on seismic excitations on the horizontal plane,the statistics of the angles between the major response axis and the major principal axis are obtained;GMPEs along the principal axes are provided and compared with those obtained for a randomly oriented horizontal component;and statistical analysis of residuals associated with GMPEs along the principal directions is carried out.  相似文献   

20.
Private wells are the source of drinking water for approximately 15% of households in the United States, but these wells are not regulated or monitored by government agencies. The well waters can contain arsenic, a known carcinogen that occurs in groundwater throughout the nation at concentrations that can exceed the Maximum Contaminant Level defined by the U.S. Environmental Protection Agency (10 ppb). In order to reduce arsenic exposure, homeowners can either rely on bottled water for drinking or install in-house water treatment systems for arsenic removal. Here, we document the arsenic levels associated with these options. We examined 24 different major bottled water brands and found that all have arsenic levels <1.5 parts per billion (ppb), and more than half have levels below our measurement detection limit of 0.005 ppb. For in-house treatment systems, we examined the performance of arsenic removal by point-of-use reverse osmosis filtration, and by whole-house and point-of-use filters containing granulated ferric oxide. Our results show that long-term (2 years) filtration with granulated ferric oxide reduced arsenic in well water from an initial concentration of 4 to 9 ppb down to <0.005 ppb, validating this technology as an effective form of arsenic remediation for private homes.  相似文献   

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