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Sample records for groundwater environment electronic

  1. Extreme environment electronics

    CERN Document Server

    Cressler, John D

    2012-01-01

    Unfriendly to conventional electronic devices, circuits, and systems, extreme environments represent a serious challenge to designers and mission architects. The first truly comprehensive guide to this specialized field, Extreme Environment Electronics explains the essential aspects of designing and using devices, circuits, and electronic systems intended to operate in extreme environments, including across wide temperature ranges and in radiation-intense scenarios such as space. The Definitive Guide to Extreme Environment Electronics Featuring contributions by some of the world's foremost exp

  2. Quantification of groundwater recharge in urban environments.

    Science.gov (United States)

    Tubau, Isabel; Vázquez-Suñé, Enric; Carrera, Jesús; Valhondo, Cristina; Criollo, Rotman

    2017-08-15

    Groundwater management in urban areas requires a detailed knowledge of the hydrogeological system as well as the adequate tools for predicting the amount of groundwater and water quality evolution. In that context, a key difference between urban and natural areas lies in recharge evaluation. A large number of studies have been published since the 1990s that evaluate recharge in urban areas, with no specific methodology. Most of these methods show that there are generally higher rates of recharge in urban settings than in natural settings. Methods such as mixing ratios or groundwater modeling can be used to better estimate the relative importance of different sources of recharge and may prove to be a good tool for total recharge evaluation. However, accurate evaluation of this input is difficult. The objective is to present a methodology to help overcome those difficulties, and which will allow us to quantify the variability in space and time of the recharge into aquifers in urban areas. Recharge calculations have been initially performed by defining and applying some analytical equations, and validation has been assessed based on groundwater flow and solute transport modeling. This methodology is applicable to complex systems by considering temporal variability of all water sources. This allows managers of urban groundwater to evaluate the relative contribution of different recharge sources at a city scale by considering quantity and quality factors. The methodology is applied to the assessment of recharge sources in the Barcelona city aquifers. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Microbially induced corrosion of carbon steel in deep groundwater environment

    Directory of Open Access Journals (Sweden)

    Pauliina eRajala

    2015-07-01

    Full Text Available The metallic low and intermediate level radioactive waste generally consists of carbon steel and stainless steels. The corrosion rate of carbon steel in deep groundwater is typically low, unless the water is very acidic or microbial activity in the environment is high. Therefore, the assessment of microbially induced corrosion of carbon steel in deep bedrock environment has become important for evaluating the safety of disposal of radioactive waste. Here we studied the corrosion inducing ability of indigenous microbial community from a deep bedrock aquifer. Carbon steel coupons were exposed to anoxic groundwater from repository site 100 m depth (Olkiluoto, Finland for periods of three and eight months. The experiments were conducted at both in situ temperature and room temperature to investigate the response of microbial population to elevated temperature. Our results demonstrate that microorganisms from the deep bedrock aquifer benefit from carbon steel introduced to the nutrient poor anoxic deep groundwater environment. In the groundwater incubated with carbon steel the planktonic microbial community was more diverse and 100-fold more abundant compared to the environment without carbon steel. The betaproteobacteria were the most dominant bacterial class in all samples where carbon steel was present, whereas in groundwater incubated without carbon steel the microbial community had clearly less diversity. Microorganisms induced pitting corrosion and were found to cluster inside the corrosion pits. Temperature had an effect on the species composition of microbial community and also affected the corrosion deposits layer formed on the surface of carbon steel.

  4. Analysis of sex hormones in groundwater using electron impact ionization

    Energy Technology Data Exchange (ETDEWEB)

    Gonschorowski, Graciele Pereira da Cruz, E-mail: graci_ju@yahoo.com.br [Universidade Estadual do Centro-Oeste (UNICENTRO), Guarapuava, PR (Brazil); Gonschorowski, Juliano dos Santos, E-mail: jgsantosbr@yahoo.com.br [Universidade Federal Tecnologica do Parana (UTFPR), Guarapuava, PR (Brazil); Shihomatsu, Helena M.; Bustillos, Jose Oscar Vega, E-mail: hmatsu@ipen.br, E-mail: ovega@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Limeira, Larissa, E-mail: larissa.limeira07@gmail.com [Centro Universitario FIEO (UNIFIEO), Sao Paulo, SP (Brazil)

    2013-07-01

    A wide range of estrogenic contaminants has been detected in the aquatic environment, both in natural and synthetic forms. Steroid hormones are endocrine-disrupting compounds, which affect the endocrine system at very low concentrations. This work presents the development of an analytical procedure for the determination of five sexual steroid hormones, 17β-estradiol, estrone, progesterone, and the synthetics contraceptives, 17α-ethynylestradiol and norgestrel in groundwater from Sao Paulo University campus, specifically at Institute of Energy and Nuclear Research (IPEN). The analytical procedure starting with the sample pre-treatment, where the samples were first filtered and then extracted through solid-phase extraction, using Strata-X cartridges, and ending with detection. The separation method used was gas chromatography (GC), and the detection method was mass spectrometry (MS). The ion source used was electron impact ionization which produced an electron beam generated by an incandescent tungsten/thorium filament, which collide with molecules of gas sample. This interaction between the electrons and molecules, produce ions of the sample. The detection limits 0.06μg.L{sup -1} for estrone, 0.13 μg. L{sup -1} for 17β-estradiol, 0.13 μg.L{sup -1} for 17α-ethynylestradiol, 0.49 μg.L{sup -1} for norgestrel and 0.02 μg.L{sup -1} for progesterone were detected in assays matrix. Validating tests were also used in this work. (author)

  5. Geological Environment Problems Caused by Controlling Groundwater Exploitation in Jiangyin City

    Institute of Scientific and Technical Information of China (English)

    DENG Qing-hai; MA Feng-shan; YUAN Ren-mao; YAO Bing-kui

    2007-01-01

    Geological environment effects caused by the control of groundwater exploitation in Jiangyin city are discussed thoroughly, including the dynamic variation of groundwater levels and quality and the development of land subsidence and ground fissures. According to the dynamic characteristics of groundwater levels, some advice about groundwater exploitation is offered. Our research will provide a basis for using groundwater resources and the prevention of geological disasters in Jiangyin city and the Suzhou-Wuxi-Changzhou area. The following results are deduced from our research. First, groundwater levels vary with the exploitation of groundwater in Jiangyin city and are affected by hydrogeological conditions. The groundwater levels remained rather stable before and after the implementation of control of groundwater exploitation in the northwest of Jiangyin city along the Yangtze River. A suitable level of exploitation should be allowed. In the southeast, the speed of recovery of the groundwater level has been rather rapid after the control of exploitation. We conclude that groundwater might be exploited locally after the groundwater level has recovered. In the southwest, the speed of recovery of the groundwater level is rather slow and exploitation of groundwater should be prohibited. Second, groundwater quality is stable in Jiangyin city and the contents of the main chemical indices of groundwater varied only slightly before and after the control of exploitation. Third, after controlling the exploitation, the speed of land subsidence has clearly slowed down and the development of ground fissures has been controlled effectively.

  6. Investigations of air and groundwater pollution of the rural environment

    Energy Technology Data Exchange (ETDEWEB)

    Kerenyi, Attila; Csorba, Peter (Institute of Applied Landscape Geography, Kossuth L. University, Debrecen (Hungary))

    1993-12-01

    Within the framework of landscape investigations in the environment of Cserepfalu-Bogacs, air and groundwater pollution was regularly monitored. Automatic instruments were used to measure SO[sub 2] content of the air for one day, and NO[sub x] content for the following day. Characteristic periods of the year were selected for air pollution, so that several weeks of continuous measurements in each season were obtained. The air pollution data measured in Cserepfalu are nearly always characteristic of the wider environment (background values). In the centre of Bogacs, SO[sub 2] pollution as a result of winter heating can be well observed; the amount of NO[sub x] is mostly determined by the increased traffic in summer. During a windless and very cold November, SO[sub 2] contamination in Bogacs greatly exceeded the permissible level. Groundwater examinations were carried out in the village of Cserepfalu between 1989 and 1990. The first measurements in Cserepfalu, between May and September 1988, showed little contamination, and the nitrate content was practically constant at 30 mg dm[sup -3] in the four main wells. In June 1989 the nitrate content of the water in these wells rose 4-7-fold by the end of the month. The characteristic nitrate concentration was found to be 80-150 mg dm[sup -3] and 150-250 mg dm[sup -3], but there were some places with values above 400 mg dm[sup -3]. These high values were found on the outskirts of the village, in an intensively cultivated agricultural area; thus the agricultural origin of the contamination is probable

  7. Groundwater.

    Science.gov (United States)

    Braids, Olin C.; Gillies, Nola P.

    1978-01-01

    Presents a literature review of groundwater quality covering publications of 1977. This review includes: (1) sources of groundwater contamination; and (2) management of groundwater. A list of 59 references is also presented. (HM)

  8. Soil CO2 Uptake in Deserts and Its Implications to the Groundwater Environment

    Directory of Open Access Journals (Sweden)

    Wenfeng Wang

    2016-09-01

    Full Text Available Recent studies of soil carbon cycle in arid and semi-arid ecosystems demonstrated that there exists an abiotic CO2 absorption by saline-alkali soils (Aa at desert ecosystems and suggested potential contributions of CO2 dissolution beneath deserts to the terrestrial ecosystems carbon balance. However, the overall importance of such soil CO2 uptake is still undetermined and its implications to the groundwater environment remain unaddressed. In this manuscript, a simple method is proposed for the direct computation of Aa from the total soil CO2 flux (Fa as well as for the evaluation of Aa importance to Fa. An artificial soil-groundwater system was employed to investigate the implications to groundwater environment and it was found that soil CO2 uptake in deserts can contribute a possible influence on the evolution of the groundwater environment, providing that the absorbed CO2 largely remained in the soil-groundwater system.

  9. DRASTIC-based vulnerability evaluation for groundwater environment in Kunming City

    Institute of Scientific and Technical Information of China (English)

    Changming WANG; Jianping CHEN; Pulin LI; Hao ZHANG; Lijian YANG

    2006-01-01

    Groundwater pollution has serious influences on programming and development for a city. So it has a special importance to assess reasonably the vulnerability to pollution for urban groundwater. DRASTIC is an effective method for groundwater vulnerability assessment, which has been adapted in USA and Europe countries. In this paper, DRASTIC method is applied in vulnerability assessment of shallow groundwater environment in Kunming. A total of 1 339 units are divided in this area and the grade of each unit for seven indexes is determined. Then vulnerability zones are divided in the area by DRASTIC value, which has an important meaning to city programming.

  10. SOI MESFETs for Extreme Environment Electronics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We are proposing a new extreme environment electronics (EEE) technology based on silicon-on-insulator (SOI) metal-semiconductor field-effect transistors (MESFETs)....

  11. Artificial sweeteners as potential tracers in groundwater in urban environments

    Science.gov (United States)

    Van Stempvoort, Dale R.; Roy, James W.; Brown, Susan J.; Bickerton, Greg

    2011-04-01

    SummaryThere is little information available on the prevalence of artificial sweeteners in groundwater, though these compounds may prove to be useful tracers of human wastewater, especially in urban settings with complex hydrology. In this study, the artificial sweetener acesulfame was detected in groundwater at all eight urban sites investigated (from five different urban areas in Canada), often at high concentrations (i.e., μg/L-scale). In a municipal wastewater plume at Jasper, Alberta, acesulfame was strongly correlated with chloride and was positively correlated with other wastewater-related contaminants indicating that this sweetener has potential to be a good tracer of young wastewater (artificial sweeteners were detected in urban groundwater: saccharin at six of the sites, sucralose at three sites, and cyclamate at five of seven sites where it was analyzed. The occurrence of sucralose may have been affected by its detection limit, which was much higher than for the other sweeteners. These results, and those of a parallel study, are the first reported detections of saccharin and cyclamate in groundwater, and suggest that these sweeteners may be more common than previously anticipated. In general, fewer samples from each site contained these other three sweeteners compared to acesulfame. At Barrie, Ontario, adjacent to an old landfill, the concentration of saccharin was higher than acesulfame in many samples. These results suggest that analyses of multiple sweeteners, rather than just acesulfame, may provide useful information on contaminant sources and groundwater conditions in urban settings. Further work is needed to address this potential use.

  12. Supported Text in Electronic Reading Environments.

    Science.gov (United States)

    Horney, Mark A.; Anderson-Inman, Lynne

    1999-01-01

    Defines "electronic books," and shares examples of prior research on the use of such environments to improve the reading fluency and comprehension of students with reading difficulties. Presents a taxonomy of the types of supportive resources that have emerged from efforts to design and research the use of electronic books, and presents…

  13. Electronic Market and Business: Cyberspace vs. Electronic Environment

    Directory of Open Access Journals (Sweden)

    Deniss Ščeulovs

    2013-12-01

    Full Text Available The authors of the article analyze the concept "electronic environment". Having studied a range of academic literature sources and other sources, the authors of the article have drawn a conclusion that the academic writings do not provide a definition of "electronic environment". Furthermore, the various opinions among specialists regarding this concept often differ. Meanwhile, there are several explanations of the term "cyberspace" overlapping the concept of "electronic environment", and these terms are often believed to be synonyms. To understand what the term "electronic environment" means and to properly and correctly employ this concept in entrepreneurship, the authors have performed a lexicographic analysis of this concept by comparing reciprocal concepts. As a result of the research, the authors propose their view on what, in their opinion, "electronic environment" is and what its connection to the concept "cyberspace" is. The topicality of the article lies in the fact that often entrepreneurs and specialists of public and other institutions, when using these terms, imply completely different concepts. It can lead to misunderstanding and misinterpreting the information, as well as to encumbering the understanding of tasks, problems, etc.

  14. Measurement and modeling of phosphorous transport in shallow groundwater environments.

    Science.gov (United States)

    Hendricks, G S; Shukla, S; Obreza, T A; Harris, W G

    2014-08-01

    Leaching of phosphorus (P) from agricultural soils, especially those that are sandy, is adversely impacting P-limited ecosystems like Florida's Everglades. A more developed understanding of P and water management strategies and their effects on P leaching is needed to achieve reductions in subsurface P losses, especially from intensively managed dual cropping systems under plastic mulch in shallow water regions. We compared the effects of conservation P and water management strategies with traditional practices on P transport to groundwater. A 3-year experiment was conducted on hydrologically isolated plots with plastic-mulched successive cropping systems to compare high (HEI) and soil test based recommended (REI) external input (water and fertilizer P) systems with traditional sub-irrigation (seepage), and REI with a potential water conservation subsurface drip irrigation system (REI-SD) with regard to groundwater P concentrations above and below the low conductivity spodic horizon (Bh). The REI treatments had higher available storage for rainfall and P than HEI. Use of both REI systems (REI=2098μg/L and REI-SD=2048μg/L) reduced groundwater P concentrations above the Bh horizon by 33% compared to HEI (3090μg/L), and results were significant at the 0.05 level. Although the subsurface drip system saved water, it did not offer any groundwater quality (P) benefit. Mixing and dilution of influent P below the low conductivity Bh horizon between treatments and with the regional groundwater system resulted in no significant differences in groundwater P concentration below the Bh horizon. Groundwater P concentrations from this study were higher than reported elsewhere due to low soil P storage capacity (SPSC), high hydraulic conductivity of sandy soils, and a high water table beneath crop beds. The HEI system leached more P due to ferilizer P in excess of SPSC and used higher irrigation volumes compared with REI systems. Despite a 40% difference in the average amount of

  15. Electronic materials processing and the microgravity environment

    Science.gov (United States)

    Witt, A. F.

    1988-01-01

    The nature and origin of deficiencies in bulk electronic materials for device fabrication are analyzed. It is found that gravity generated perturbations during their formation account largely for the introduction of critical chemical and crystalline defects and, moreover, are responsible for the still existing gap between theory and experiment and thus for excessive reliance on proprietary empiricism in processing technology. Exploration of the potential of reduced gravity environment for electronic materials processing is found to be not only desirable but mandatory.

  16. Correlated electrons in a dissipative environment

    Science.gov (United States)

    Bulla, R.

    2009-12-01

    When a system of correlated electrons is embedded in a dissipative environment, new emergent phenomena might occur due to the interplay of correlation and dissipation. Here we focus on quantum impurity systems with coupling to a bosonic bath. For the theoretical investigation we introduce the bosonic numerical renormalization group method which has been initially set up for the spin-boson model. The role of both correlations and dissipation is described in the context of two-electron transfer systems. We also discuss prospects for the investigation of lattice models of correlated electrons with coupling to a dissipative bath.

  17. Public Service Guidelines in an Electronic Environment.

    Science.gov (United States)

    Barkley, Daniel C.

    1998-01-01

    In today's electronic environment, government information librarians face new challenges, especially in the arena of quality public-service provision. Given the lack of clear guidelines that Federal Depository Library Program participants follow, and based upon suggested guidelines of reference-oriented literature, a new set of public services…

  18. Hetero-Interfaces for Extreme Electronic Environments

    Science.gov (United States)

    2014-07-23

    describing the intrinsic behavior. In the original intrinsic hypothesis, it was described as the electrostatic field reaching the band gap energy...ELECTRONIC ENVIRONMENTS Quasi-two-dimensional electron gas (Q-2D-EG) forms at the interface between two perovskite band insulators; LaAlO3 (LAO) and...SrO)0 or ( TiO2 )0 – intersecting with negatively charged (AlO2)1- or positively charged (LaO)1+ layers, respectively. (this latter "LaO" layer

  19. Radiation Hardened Electronics for Extreme Environments

    Science.gov (United States)

    Keys, Andrew S.; Watson, Michael D.

    2007-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project consists of a series of tasks designed to develop and mature a broad spectrum of radiation hardened and low temperature electronics technologies. Three approaches are being taken to address radiation hardening: improved material hardness, design techniques to improve radiation tolerance, and software methods to improve radiation tolerance. Within these approaches various technology products are being addressed including Field Programmable Gate Arrays (FPGA), Field Programmable Analog Arrays (FPAA), MEMS Serial Processors, Reconfigurable Processors, and Parallel Processors. In addition to radiation hardening, low temperature extremes are addressed with a focus on material and design approaches.

  20. Logistics, electronic commerce, and the environment

    Science.gov (United States)

    Sarkis, Joseph; Meade, Laura; Talluri, Srinivas

    2002-02-01

    Organizations realize that a strong supporting logistics or electronic logistics (e-logistics) function is important from both commercial and consumer perspectives. The implications of e-logistics models and practices cover the forward and reverse logistics functions of organizations. They also have direct and profound impact on the natural environment. This paper will focus on a discussion of forward and reverse e-logistics and their relationship to the natural environment. After discussion of the many pertinent issues in these areas, directions of practice and implications for study and research are then described.

  1. Environment tracers application to groundwater circulation assessment in an alluvial aquifer in Central Italy

    Science.gov (United States)

    Sappa, Giuseppe; Barbieri, Maurizio; Vitale, Stefania

    2017-04-01

    Groundwater vulnerability assessment is an important tool in order to plan any groundwater protection strategy. The aim of this study is to experiment a specific approach to give a conceptual model about groundwater circulation characterization. This approach has been applied to a suspected contaminated site in a large alluvial plan, made of sediments coming from weathered volcanic rocks, laying on marine sediments, where more than thirty years ago had been built a very important urban waste solid landfill. In referring to this case history it has been pointed out the importance of natural chemical interaction between ground water and rock mass, especially when pyroclastic origin sediments are involved. The landfill had been isolated from the surrounding environment, especially to protect aquifers, by a waterproof diaphragm This land is characterised by intensive agricultural and industrial activities (oil refineries, medical waste incinerators, concrete production, tar factory). The study will highlight the importance of environmental tracers which provide information about the flow and mixing processes of water coming from different sources. They are also useful to point out directions of groundwater flow and to determine origin Environmental tracers are natural chemical and isotopic substances that can be measured in groundwater and used to understand hydrologic properties of aquifers. They may be input into the hydrological system from the atmosphere at recharge and/or are added/lost/exchanged inherently as waters flow over and through materials. Variations in their chemical abundances and isotopic compositions can be used as tracers to determine sources (provenance), pathways (of reaction or interaction) and also timescales (dating) of environmental processes. In combination with these, the basic idea is to use. In this case enviromental tracers have been integrated by temperature and electric conductivity logs, to better investigate different levels of faster

  2. Management of karstic coastal groundwater in a changing environment (Salento, southern Italy)

    Science.gov (United States)

    Polemio, Maurizio; Romanazzi, Andrea

    2014-05-01

    groundwater trends from 1930 to 2060 and emphasizes an essential decrease of piezometric level and a huge worsening of the groundwater salinisation due seawater intrusion. More details on previous results of this research activity were recently published (Polemio and Romanazzi, 2012; Romanazzi and Polemio, 2013). References Polemio M., Romanazzi A., (2013), A groundwater model to support the management water resources of coastal karstic aquifer of salento (south italy), Rend. Online Soc. Geol. It., Atti del IX Convegno Nazionale dei Giovani Ricercatori di Geologia Applicata, Vol. 24 (2013), pp. 254-256. Romanazzi A., Polemio M., (2013), Modelling of coastal karst aquifers for management support: Study of Salento (Apulia, Italy), Italian Journal of Engineering Geology and Environment, 13, 1, pp. 65-83.

  3. An Ecohydrologic Model for a Shallow Groundwater Urban Environment

    Science.gov (United States)

    The urban environment is a patchwork of natural and artificial surfaces that results in complex interactions with and impacts to natural hydrologic cycles. Evapotranspiration (ET) is a major hydrologic flow that is often altered from urbanization, though the mechanisms of change ...

  4. Reconfiguration of Analog Electronics for Extreme Environments

    Science.gov (United States)

    Stoica, Adrian; Zebulum, Ricardo; Keymeulen, Didier; Guo, Xin

    2005-01-01

    This paper argues in favor of adaptive reconfiguration as a technique to expand the operational envelope of analog electronics for extreme environments (EE). On a reconfigurable device, although component parameters change in EE, as long as devices still operate, albeit degraded, a new circuit design, suitable for new parameter values, may be mapped into the reconfigurable structure to recover the initial circuit function. Laboratory demonstrations of this technique were performed by JPL in several independent experiments in which bulk CMOS reconfgurable devices were exposed to, and degraded by, high temperatures (approx.300 C) or radiation (300kRad TID), and then recovered by adaptive reconfiguration using evolutionary search algorithms.

  5. Village environs as source of nitrate contamination in groundwater: a case study in basaltic geo-environment in central India.

    Science.gov (United States)

    Reddy, D V; Nagabhushanam, P; Peters, Edward

    2011-03-01

    Nitrate is one of the common contaminants in the present day groundwaters resulting from increased population associated with poor sanitary conditions in the habitat area and increased agricultural activity. The hydrochemical measurements on water samples from a virgin watershed, situated in the basaltic geo-environment, have become necessary as the groundwater is the only source of drinking water for the villagers of the area. High preferential recharge conditions prevail in the area due to fractures in the solid basaltic lava flows. Instead of dilution due to fresh recharge, the post-monsoon hydrochemical concentrations in the groundwater are observed to have increased probably due to fast migration of pollutants to the aquifer through preferential recharge. As a result, the deep aquifer waters are more contaminated with hazardous nitrate than the shallow waters. Further, the village environ wells are more polluted with nitrate than the agriculture areas which could be attributed to the unhygienic sanitary conditions and livestock waste dump pits in the villages. This study suggests proper management of the sewage system and creation of suitable dump yard for the livestock and household waste to minimize the level of nitrate pollution in the well waters of village environs.

  6. Electronic Cigarette Topography in the Natural Environment.

    Directory of Open Access Journals (Sweden)

    R J Robinson

    Full Text Available This paper presents the results of a clinical, observational, descriptive study to quantify the use patterns of electronic cigarette users in their natural environment. Previously published work regarding puff topography has been widely indirect in nature, and qualitative rather than quantitative, with the exception of three studies conducted in a laboratory environment for limited amounts of time. The current study quantifies the variation in puffing behaviors among users as well as the variation for a given user throughout the course of a day. Puff topography characteristics computed for each puffing session by each subject include the number of subject puffs per puffing session, the mean puff duration per session, the mean puff flow rate per session, the mean puff volume per session, and the cumulative puff volume per session. The same puff topography characteristics are computed across all puffing sessions by each single subject and across all subjects in the study cohort. Results indicate significant inter-subject variability with regard to puffing topography, suggesting that a range of representative puffing topography patterns should be used to drive machine-puffed electronic cigarette aerosol evaluation systems.

  7. [Groundwater].

    Science.gov (United States)

    González De Posada, Francisco

    2012-01-01

    From the perspective of Hydrogeology, the concept and an introductory general typology of groundwater are established. From the perspective of Geotechnical Engineering works, the physical and mathematical equations of the hydraulics of permeable materials, which are implemented, by electric analogical simulation, to two unique cases of global importance, are considered: the bailing during the construction of the dry dock of the "new shipyard of the Bahia de Cádiz" and the waterproofing of the "Hatillo dam" in the Dominican Republic. From a physical fundamental perspective, the theories which are the subset of "analogical physical theories of Fourier type transport" are related, among which the one constituted by the laws of Adolf Fick in physiology occupies a historic role of some relevance. And finally, as a philosophical abstraction of so much useful mathematical process, the one which is called "the Galilean principle of the mathematical design of the Nature" is dealt with.

  8. Field Evidence for Co-Metabolism of Trichloroethene Stimulated by Addition of Electron Donor to Groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Conrad, Mark E.; Brodie, Eoin L.; Radtke, Corey W.; Bill, Markus; Delwiche, Mark E.; Lee, M. Hope; Swift, Dana L.; Colwell, Frederick S.

    2010-05-17

    For more than 10 years, electron donor has been injected into the Snake River aquifer beneath the Test Area North site of the Idaho National Laboratory for the purpose of stimulating microbial reductive dechlorination of trichloroethene (TCE) in groundwater. This has resulted in significant TCE removal from the source area of the contaminant plume and elevated dissolved CH4 in the groundwater extending 250 m from the injection well. The delta13C of the CH4 increases from 56o/oo in the source area to -13 o/oo with distance from the injection well, whereas the delta13C of dissolved inorganic carbon decreases from 8 o/oo to -13 o/oo, indicating a shift from methanogenesis to methane oxidation. This change in microbial activity along the plume axis is confirmed by PhyloChip microarray analyses of 16S rRNA genes obtained from groundwater microbial communities, which indicate decreasing abundances of reductive dechlorinating microorganisms (e.g., Dehalococcoides ethenogenes) and increasing CH4-oxidizing microorganisms capable of aerobic co-metabolism of TCE (e.g., Methylosinus trichosporium). Incubation experiments with 13C-labeled TCE introduced into microcosms containing basalt and groundwater from the aquifer confirm that TCE co-metabolism is possible. The results of these studies indicate that electron donor amendment designed to stimulate reductive dechlorination of TCE may also stimulate co-metabolism of TCE.

  9. Modeling Multiple Stresses Placed Upon A Groundwater System In A Semi-Arid Brackish Environment

    Science.gov (United States)

    Toll, M.; Salameh, E.; Sauter, M.

    2008-12-01

    In semi-arid areas groundwater systems are frequently not sufficiently characterized hydrogeologically and long term data records are generally not available. Long-term time series are necessary, however to design future groundwater abstraction scenarios or to predict the influence of future climate change effects on groundwater resources. To overcome these problems an integrated approach for the provision of a reliable database based on sparse and fuzzy data is proposed. This integrated approach is demonstrated in the lowermost area of the Jordan Valley. The Jordan Valley is part of the Jordan Dead Sea Wadi Araba Rift Valley, which extends from the Red Sea to lake Tiberias and beyond with a major 107 km sinistral strike-slip fault between the Arabian plate to the east and the northeastern part of the African plate to the west. Due to extensional forces a topographic depression was formed. As a result of an arid environment it is filled with evaporites, lacustrine sediments, and clastic fluvial components. A subtropical climate with hot, dry summers and mild humid winters with low amounts of rainfall provide excellent farming conditions. Therefore the Jordan Valley is considered as the food basket of Jordan and is used intensively for agriculture. As a result hundreds of shallow wells were drilled and large amounts of groundwater were abstracted since groundwater is the major source for irrigation. Consequently groundwater quality decreased rapidly since the sixties and signs of overpumping and an increase in soil salinity could clearly be seen. In order to achieve a sustainable state of water resources and to quantify the impact of climate change on water resources a proper assessment of the groundwater resources as well as their quality is a prerequisite. In order to sufficiently describe the complex hydrogeologic flow system an integrated approach, combining geological, geophysical, hydrogeological, historical, and chemical methods was chosen. The aquifer

  10. Corrosion testing of type 304L stainless steel in tuff groundwater environments

    Energy Technology Data Exchange (ETDEWEB)

    Westerman, R.E.; Pitman, S.G.; Haberman, J.H.

    1987-11-01

    The stress-corrosion cracking (SCC) resistance of Type 304L stainless steel (SS) to elevated temperatures in tuff rock and tuff groundwater environments was determined under irradiated and nonirradiated conditions using U-bend specimens and slow-strain-rate tests. The steel was tested both in the solution-annealed condition and after sensitization heat treatments. The material was found to be susceptible to SCC in both the solution-annealed and solution-annealed-and-sensitized conditions when exposed to an irradiated crushed tuff rock environment containing air and water vapor at 90{sup 0}C. A similar exposure at 50{sup 0}C did not result in failure after a 25-month test duration. Specimens of sensitized 304 SS conditioned with a variety of sensitization heat treatments resisted failure during a test of 1-year duration in which a nonirradiated environment of tuff rock and groundwater held at 200{sup 0}C was allowed to boil to dryness on a cyclical basis. All specimens of sensitized 304 SS exposed to this environment failed. Slow-strain-rate studies were performed on 304L, 304, and 316L SS specimens. The 304L SS was tested in J-13 well water at 150{sup 0}C, and the 316L SS at 95{sup 0}C. Neither material showed evidence of SCC in these tests. Sensitized 304 SS did exhibit SCC in J-13 well water in tests conducted at 150{sup 0}C. 12 refs., 27 figs., 13 tabs.

  11. Forecasting the Depletion of Transboundary Groundwater Resources in Hyper-Arid Environments

    Science.gov (United States)

    Mazzoni, A.; Heggy, E.

    2014-12-01

    The increase in awareness about the overexploitation of transboundary groundwater resources in hyper-arid environments that occurred in the last decades has highlighted the need to better map, monitor and manage these resources. Climate change, economic and population growth are driving forces that put more pressure on these fragile but fundamental resources. The aim of our approach is to address the question of whether or not groundwater resources, especially non-renewable, could serve as "backstop" water resource during water shortage periods that would probably affect the drylands in the upcoming 100 years. The high dependence of arid regions on these resources requires prudent management to be able to preserve their fossil aquifers and exploit them in a more sustainable way. We use the NetLogo environment with the FAO Aquastat Database to evaluate if the actual trends of extraction, consumption and use of non-renewable groundwater resources would remain feasible with the future climate change impacts and the population growth scenarios. The case studies selected are three: the Nubian Sandstone Aquifer System, shared between Egypt, Libya, Sudan and Chad; the North Western Sahara Aquifer System, with Algeria, Tunisia and Libya and the Umm Radhuma Dammam Aquifer, in its central part, shared between Saudi Arabia, Qatar and Bahrain. The reason these three fossil aquifers were selected are manifold. First, they represent properly transboundary non-renewable groundwater resources, with all the implications that derive from this, i.e. the necessity of scientific and socio-political cooperation among riparians, the importance of monitoring the status of shared resources and the need to elaborate a shared management policy. Furthermore, each country is characterized by hyper-arid climatic conditions, which will be exacerbated in the next century by climate change and lead to probable severe water shortage periods. Together with climate change, the rate of population

  12. Faulting and groundwater in a desert environment: constraining hydrogeology using time-domain electromagnetic data

    Science.gov (United States)

    Bedrosian, Paul A.; Burgess, Matthew K.; Nishikawa, Tracy

    2013-01-01

    Within the south-western Mojave Desert, the Joshua Basin Water District is considering applying imported water into infiltration ponds in the Joshua Tree groundwater sub-basin in an attempt to artificially recharge the underlying aquifer. Scarce subsurface hydrogeological data are available near the proposed recharge site; therefore, time-domain electromagnetic (TDEM) data were collected and analysed to characterize the subsurface. TDEM soundings were acquired to estimate the depth to water on either side of the Pinto Mountain Fault, a major east-west trending strike-slip fault that transects the proposed recharge site. While TDEM is a standard technique for groundwater investigations, special care must be taken when acquiring and interpreting TDEM data in a twodimensional (2D) faulted environment. A subset of the TDEM data consistent with a layered-earth interpretation was identified through a combination of three-dimensional (3D) forward modelling and diffusion time-distance estimates. Inverse modelling indicates an offset in water table elevation of nearly 40 m across the fault. These findings imply that the fault acts as a low-permeability barrier to groundwater flow in the vicinity of the proposed recharge site. Existing production wells on the south side of the fault, together with a thick unsaturated zone and permeable near-surface deposits, suggest the southern half of the study area is suitable for artificial recharge. These results illustrate the effectiveness of targeted TDEM in support of hydrological studies in a heavily faulted desert environment where data are scarce and the cost of obtaining these data by conventional drilling techniques is prohibitive.

  13. Modeling Changing Morphology and Density Dependent Groundwater Flow in a Dynamic Environment: case study

    Science.gov (United States)

    Huizer, Sebastian; Bierkens, Marc; Oude Essink, Gualbert

    2015-04-01

    The prospect of sea level rise and increase in extreme weather conditions has led to a new focus on coastal defense in the Netherlands. As an innovative solution for coastal erosion a mega-nourishment named the Sand Motor (or Sand Engine) has been constructed at the Dutch coast. This body of sand will be distributed slowly along the coastline by wind, waves and currents; keeping the coastal defense structures in place and creating a unique, dynamic environment with changing morphology over time. The large size and position of the Sand Motor might lead to a substantial increase of fresh ground water resources. This creates an opportunity to combine coastal protection with an increase of fresh water resources in coastal regions. With a three dimensional, density dependent, groundwater model the effects of changing morphology over time and the potential increase in fresh water availability have been studied. The preliminary model calculations show that in a period of 20 years volume of fresh water gradually increases to ca. 12 Mm3. In the nearby dune area 7-8 Mm3 is abstracted yearly, therefore the first results are promising in increasing fresh groundwater resources. More model calculations will be performed to investigate the sensitivity of the change in the fresh, brackish and salt water distribution.

  14. Distribution of groundwater nitrate contamination in GIS environment: A case study, Sonqor plain

    Directory of Open Access Journals (Sweden)

    Parasto Setareh

    2014-06-01

    Full Text Available Background: Nitrate is a pollutant of groundwater resources which can results health risks such as methemoglobinemia and formation of nitrosamine compounds in higher concentration limits. The present study was aimed to determine the nitrite level, causes of pollution and zonation of nitrite concentration in drinking water resources in the villages of Sonqor. Methods: In this descriptive-analytrical study, 73 samples of all groundwater resources of Sonqor plain were taken in ,high water (March 2010 and low water (September 2011 periods. Water nitrate levels were then determined by spectrophotometry. Results were compared by national standards and analyzed by SPSS and Arcview GIS 9.3 software. Finally, the concentration distribution mapping was carried out in GIS environment and the factors affecting nitrite changes were analyzed. Results: nitrate concentration of water resources of Sonqor plain was fluctuating at 3.09-88.5 mg per liter.In one station, nitrite concentrations in the high (88.5 mg/liter and low (71.4 mg/liter water seasons were higher than the maximum limit. Based on the maps, a relatively high concentration of nitrite was observed in the Eastern and Southeastern regions. Conclusion: The findings indicated a reverse correlation between nitrite concentration changes and changes of static surface depth. Low thickness of alluvium, location of wells in the downstream farmlands, farming condition of the region, nitrate leaching from agricultural soils and wide application of nitrogen fertilizers in agriculture were considered as the causes of the pollution in one station.

  15. Molybdenum Availability Is Key to Nitrate Removal in Contaminated Groundwater Environments.

    Science.gov (United States)

    Thorgersen, Michael P; Lancaster, W Andrew; Vaccaro, Brian J; Poole, Farris L; Rocha, Andrea M; Mehlhorn, Tonia; Pettenato, Angelica; Ray, Jayashree; Waters, R Jordan; Melnyk, Ryan A; Chakraborty, Romy; Hazen, Terry C; Deutschbauer, Adam M; Arkin, Adam P; Adams, Michael W W

    2015-08-01

    The concentrations of molybdenum (Mo) and 25 other metals were measured in groundwater samples from 80 wells on the Oak Ridge Reservation (ORR) (Oak Ridge, TN), many of which are contaminated with nitrate, as well as uranium and various other metals. The concentrations of nitrate and uranium were in the ranges of 0.1 μM to 230 mM and nitrate reduction branch of the global nitrogen cycle. It is required at the catalytic site of nitrate reductase, the enzyme that reduces nitrate to nitrite. Moreover, more than 85% of the groundwater samples contained less than 10 nM Mo, whereas concentrations of 10 to 100 nM Mo were required for efficient growth by nitrate reduction for two Pseudomonas strains isolated from ORR wells and by a model denitrifier, Pseudomonas stutzeri RCH2. Higher concentrations of Mo tended to inhibit the growth of these strains due to the accumulation of toxic concentrations of nitrite, and this effect was exacerbated at high nitrate concentrations. The relevance of these results to a Mo-based nitrate removal strategy and the potential community-driving role that Mo plays in contaminated environments are discussed.

  16. Student Performance in an Electronic Text Environment.

    Science.gov (United States)

    Friedman, Edward A.; And Others

    1989-01-01

    Describes a project conducted at Stevens Institute of Technology to develop and test the applicability of full-text electronic databases and full-text retrieval technology for use in undergraduate humanities education. The creation of a machine-readable database on Galileo is described, student reactions are discussed, and further work is…

  17. Electronic Energy Transfer in Polarizable Heterogeneous Environments

    DEFF Research Database (Denmark)

    Svendsen, Casper Steinmann; Kongsted, Jacob

    2015-01-01

    Theoretical prediction of transport and optical properties of protein-pigment complexes is of significant importance when aiming at understanding the structure versus function relationship in such systems. Electronic energy transfer (EET) couplings represent a key property in this respect since...

  18. Evaluation of sustained release polylactate electron donors for removal of hexavalent chromium from contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Brodie, E.L.; Joyner, D. C.; Faybishenko, B.; Conrad, M. E.; Rios-Velazquez, C.; Mork, B.; Willet, A.; Koenigsberg, S.; Herman, D.; Firestone, M. K.; Hazen, T. C.; Malave, Josue; Martinez, Ramon

    2011-02-15

    To evaluate the efficacy of bioimmobilization of Cr(VI) in groundwater at the Department of Energy Hanford site, we conducted a series of microcosm experiments using a range of commercial electron donors with varying degrees of lactate polymerization (polylactate). These experiments were conducted using Hanford Formation sediments (coarse sand and gravel) immersed in Hanford groundwater, which were amended with Cr(VI) and several types of lactate-based electron donors (Hydrogen Release Compound, HRC; primer-HRC, pHRC; extended release HRC) and the polylactate-cysteine form (Metal Remediation Compound, MRC). The results showed that polylactate compounds stimulated an increase in bacterial biomass and activity to a greater extent than sodium lactate when applied at equivalent carbon concentrations. At the same time, concentrations of headspace hydrogen and methane increased and correlated with changes in the microbial community structure. Enrichment of Pseudomonas spp. occurred with all lactate additions, and enrichment of sulfate-reducing Desulfosporosinus spp. occurred with almost complete sulfate reduction. The results of these experiments demonstrate that amendment with the pHRC and MRC forms result in effective removal of Cr(VI) from solution most likely by both direct (enzymatic) and indirect (microbially generated reductant) mechanisms.

  19. Postmodern theories about readers in electronic environment

    Directory of Open Access Journals (Sweden)

    Ivanka Kuić

    2015-03-01

    Full Text Available Introductory part of the paper discusses theories about readers in the last decades of the 20th century. In particular, two big theoretical schools are discussed: aesthetic reception theory and reader-response-criticism movement. Readers are a subject of very different scientific disciplines: literature theory, sociology, anthropology, book history and library science. The idea that a reader is an essential subject for future life of a literary work is common to all theorists. By constructing the theory about a reader, theorists have thought about the reader who uses the conventions of printed text. The issue whether these concepts correspond to electronic surroundings is discussed. Characteristics of the hypertext are emphasized as a new paradigm, and also the issue weather readers enjoys in hypertextual fiction. In conclusion, paper expands the virtual dimension of Isers's theory about interaction between the text and the reader, and also Fish's concept of “interpretative community” which may be constituted on the Internet as a flexible virtual community.

  20. Spatial and Temporal Variability of Groundwater Recharge in Changing Semiarid Dune Environments

    Science.gov (United States)

    Zlotnik, Vitaly; Rossman, Nathan; Rowe, Clinton; Szilagyi, Jozsef

    2014-05-01

    Groundwater recharge (GWR) is one of the major factors controlling water resources in semiarid and arid regions. This time-space-dependent flux is needed for groundwater modeling, analysis of climate change impacts, and water resources management. Typically, climate changes are studied on multi-decadal to centennial time scales, but travel times of soil moisture across the vadose zone vary broadly and may exceed multi-centennial periods in semiarid and arid environments. For given climatic conditions on the land surface, we evaluate travel times in the vadose zone and compare with times scales of climate change studies. This comparison defines the land surface areas contributing to GWR changes where travel times are shorter than times scales of climate change studies. In areas with travel times longer than climate change time scales, GWR remains unchanged over the considered period of water resources management. Such analysis allows for separation of the effect of land surface topography and vadose zone thickness from that of spatial and temporal variations in climate. Our simple travel time estimates are based on the velocity of a pressure pulse from the land surface, equivalent to a kinematic wave approximation of Richards' equation. The underlying assumptions of a unit hydraulic head gradient and relatively small magnitude of changes to upper boundary flux, caused by slow climate changes, are supported by observations in the High Plains aquifer region, USA. The input data include DEMs of land surface and groundwater table elevations, future projections of hydroclimatic variables, precipitation and evapotranspiration (WCRP-CMIP3 with hydrology VIC model outputs), and estimates of hydraulic conductivity from pedotransfer functions. Future GWR rates are estimated in four steps: GIS analysis of vadose zone thickness using difference in DEMs; evaluation of deep drainage rates based on difference between precipitation and evapotranspiration rates (PRISM and MODIS

  1. Electron Beam Freeform Fabrication in the Space Environment

    Science.gov (United States)

    Hafley, Robert A.; Taminger, Karen M. B.; Bird, R. Keith

    2007-01-01

    The influence of reduced gravitational forces (in space and on the lunar or Martian surfaces) on manufacturing processes must be understood for effective fabrication and repair of structures and replacement parts during long duration space missions. The electron beam freeform fabrication (EBF3) process uses an electron beam and wire to fabricate metallic structures. The process efficiencies of the electron beam and the solid wire feedstock make the EBF3 process attractive for use in-space. This paper will describe the suitability of the EBF3 process in the space environment and will highlight preliminary testing of the EBF3 process in a zero-gravity environment.

  2. Groundwater and human development: challenges and opportunities in livelihoods and environment.

    Science.gov (United States)

    Shah, T

    2005-01-01

    At less than 1000 km3/year, the world's annual use of groundwater is 1.5% of renewable water resource but contributes a lion's share of water-induced human welfare. Global groundwater use however has increased manifold in the past 50 years; and the human race has never had to manage groundwater use on such a large scale. Sustaining the massive welfare gains groundwater development has created without ruining the resource is a key water challenge facing the world today. In exploring this challenge, we have focused a good deal on conditions of resource occurrence but less so on resource use. I offer a typology of five groundwater demand systems as Groundwater Socio-ecologies (GwSE), each embodying a unique pattern of interactions between socio-economic and ecological variables, and each facing a distinct groundwater governance challenge. During the past century, a growing corpus of experiential knowledge has accumulated in the industrialized world on managing groundwater in various uses and contexts. A daunting global groundwater issue today is to apply this knowledge intelligently to by far the more formidable challenge that has arisen in developing regions of Asia and Africa, where groundwater irrigation has evolved into a colossal anarchy supporting billions of livelihoods but threatening the resource itself.

  3. Studies on groundwater flow and radionuclide migration at underground environments. Final report of collaboration research between JAERI and AECL

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Hiromichi; Nagao, Seiya; Yamaguchi, Tetsuji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    2001-01-01

    The Japan Atomic Energy Research Institute (JAERI) conducted a collaboration program Phase II with the Atomic Energy of Canada Limited (AECL) from 1994 to 1998. The program was started to contribute the establishment of safety assessment methodology for the geological disposal of high-level radioactive wastes on the basis of the results from the Phase I program (1987-1993). The Phase II program consisted of following experimental items: (1) radionuclide migration experiments for quarried blocks (1m x 1m x 1m) of granite with natural fracture under in-situ geochemical conditions at 240 m level of Underground Research Laboratory of AECL; (2) study on the effects of dissolved organic materials extracted from natural groundwaters on radionuclide migration; (3) study on groundwater flow using environmental isotopes at two different geologic environments; (4) development of groundwater flow and radionuclide transport model for heterogeneous geological media. The mobility of radionuclides was retarded in the fracture by the deep geological conditions and the fracture paths. The groundwater humic substances with high molecular size were enhanced for the mobility of radionuclides in the sand and granitic media due to the complexation. The application of {sup 36}Cl and {sup 129}I for the analysis on the long-term groundwater flow can be validated on the basis of investigation at the URL site. Moreover, the geostatistical model for the analysis on groundwater flow and radionuclide migration was developed, and was able to describe the groundwater flow and the migration of environmental tracers at AECL sites. This report summaries the results of the Phase II program between JAERI and AECL. (author)

  4. Evaluation of Groundwater Recharge Estimates in a Partially Metamorphosed Sedimentary Basin in a Tropical Environment: Application of Natural Tracers

    Science.gov (United States)

    Oteng Mensah, Felix; Alo, Clement

    2014-01-01

    This study tests the representativeness of groundwater recharge estimates through the chloride mass balance (CMB) method in a tropical environment. The representativeness of recharge estimates using this methodology is tested using evaporation estimates from isotope data, the general spatial distribution of the potential field, and the topographical variations in the area. This study suggests that annual groundwater recharge rates in the area ranges between 0.9% and 21% of annual precipitation. These estimates are consistent with evaporation rates computed from stable isotope data of groundwater and surface water in the Voltaian Basin. Moreover, estimates of groundwater recharge through numerical model calibration in other parts of the terrain appear to be consistent with the current data in this study. A spatial distribution of groundwater recharge in the area based on the estimated data takes a pattern akin to the spatial pattern of distribution of the hydraulic head, the local topography, and geology of the terrain. This suggests that the estimates at least qualitatively predicts the local recharge and discharge locations in the terrain. PMID:24772021

  5. Impacts of Groundwater Recharge from Rubber Dams on the Hydrogeological Environment in Luoyang Basin, China

    Science.gov (United States)

    Dong, Shaogang; Liu, Baiwei; Liu, Huamin; Wang, Shidong; Wang, Lixin

    2014-01-01

    In the rubber dam's impact area, the groundwater total hardness (TH) has declined since 2000, ultimately dropping to 100–300 mg/L in 2012. pH levels have shown no obvious changes. NH4-N concentration in the groundwater remained stable from 2000 to 2006, but it increased from 2007 to 2012, with the largest increase up to 0.2 mg/L. NO3-N concentration in the groundwater generally declined in 2000–2006 and then increased from 2007; the largest increase was to 10 mg/L in 2012. Total dissolved solids (TDS) of the groundwater showed a general trend of decline from 2000 to 2009, but levels increased after 2010, especially along the south bank of the Luohe River where the largest increase recorded was approximately 100 mg/L. This study has shown that the increases in the concentrations of NH4-N and NO3-N were probably caused by changes in groundwater levels. Nitrates adsorbed by the silt clay of aeration zone appear to have entered the groundwater through physical and chemical reactions. TDS increased because of groundwater evaporation and some soluble ions entered the groundwater in the unsaturated zone. The distance of the contaminant to the surface of the aquifer became shorter due to the shallow depth of groundwater, resulting in the observed rise in pollutant concentrations more pronounced. PMID:25126593

  6. Impacts of Groundwater Recharge from Rubber Dams on the Hydrogeological Environment in Luoyang Basin, China

    Directory of Open Access Journals (Sweden)

    Shaogang Dong

    2014-01-01

    Full Text Available In the rubber dam’s impact area, the groundwater total hardness (TH has declined since 2000, ultimately dropping to 100–300 mg/L in 2012. pH levels have shown no obvious changes. NH4-N concentration in the groundwater remained stable from 2000 to 2006, but it increased from 2007 to 2012, with the largest increase up to 0.2 mg/L. NO3-N concentration in the groundwater generally declined in 2000–2006 and then increased from 2007; the largest increase was to 10 mg/L in 2012. Total dissolved solids (TDS of the groundwater showed a general trend of decline from 2000 to 2009, but levels increased after 2010, especially along the south bank of the Luohe River where the largest increase recorded was approximately 100 mg/L. This study has shown that the increases in the concentrations of NH4-N and NO3-N were probably caused by changes in groundwater levels. Nitrates adsorbed by the silt clay of aeration zone appear to have entered the groundwater through physical and chemical reactions. TDS increased because of groundwater evaporation and some soluble ions entered the groundwater in the unsaturated zone. The distance of the contaminant to the surface of the aquifer became shorter due to the shallow depth of groundwater, resulting in the observed rise in pollutant concentrations more pronounced.

  7. 2015 Applications in Electronics Pervading Industry, Environment and Society Conference

    CERN Document Server

    2017-01-01

    This book provides a thorough overview of cutting-edge research on electronics applications relevant to industry, the environment, and society at large. It covers a broad spectrum of application domains, from automotive to space and from health to security, while devoting special attention to the use of embedded devices and sensors for imaging, communication and control. The book is based on the 2015 ApplePies Conference, held in Rome, which brought together researchers and stakeholders to consider the most significant current trends in the field of applied electronics and to debate visions for the future. Areas addressed by the conference included information communication technology; biotechnology and biomedical imaging; space; secure, clean and efficient energy; the environment; and smart, green and integrated transport. As electronics technology continues to develop apace, constantly meeting previously unthinkable targets, further attention needs to be directed toward the electronics applications and the ...

  8. Applications in Electronics Pervading Industry, Environment and Society

    CERN Document Server

    2016-01-01

    This book provides a thorough overview of cutting-edge research on electronics applications relevant to industry, the environment, and society at large. A wide spectrum of application domains are covered, from automotive to space and from health to security, and special attention is devoted to the use of embedded devices and sensors for imaging, communication, and control. The book is based on the 2014 APPLEPIES Conference, held in Rome, which brought together researchers and stakeholders to consider the most significant current trends in the field of applied electronics and to debate visions for the future. Areas covered by the conference included information communication technology; biotechnology and biomedical imaging; space; secure, clean, and efficient energy; the environment; and smart, green, and integrated transport. As electronics technology continues to develop apace, constantly meeting previously unthinkable targets, further attention needs to be directed toward the electronics applications and th...

  9. Modeling Changing Morphology and Density Dependent Groundwater Flow in a Dynamic Environment: case study

    Science.gov (United States)

    Huizer, S.; Bierkens, M. F.; Oude Essink, G.

    2014-12-01

    In many coastal regions around the world climate change will lead to a sea level rise and an increase in extreme weather conditions. This prospect has resulted in a new focus on coastal protection in the Netherlands, resulting in the initiation of an innovative coastal defence project called the Sand Motor. In this project a large body of sand or so-called mega-nourishment has been constructed along the Dutch coast. This body of sand will be distributed slowly along the coastline by wind, waves and currents. Keeping the coastal defence structures in place and creating a unique, dynamic environment with changing morphology over time. Because of the large size of the body of sand (21.5 million m3) and the position at the coastline and near coastal dunes, the Sand Motor might cause a substantial increase of the fresh water availability by increasing the volume fresh water lens underneath the dunes. This creates an opportunity to combine coastal protection with an increase of fresh water resources in coastal regions. With a three dimensional, density dependent, groundwater model the effects of changing morphology over time and the potential increase in fresh water availability have been studied.

  10. Information Spoon-Feeding in an Electronic Environment

    OpenAIRE

    C. Dugdale

    1997-01-01

    This paper examines the potential educational benefits and corresponding disadvantages of providing easily accessible and carefully selected key course texts and other course-related material in an electronic format.These findings emerged from a Library Services exercise to identify userneeds/expectations/potential use of an electronic reserve (short loan collection), before designing and installing the ResiDe system for the Faculty of the Built Environment at the University of the West of En...

  11. [Influence of human activities on groundwater environment based on coefficient variation method].

    Science.gov (United States)

    Zhao, Wei; Lin, Jian; Wang, Shu-Fang; Liu, Ji-Lai; Chen, Zhong-Rong; Kou, Wen-Jie

    2013-04-01

    Groundwater system in the plain area of Beijing can be divided into six subsystems. Due to the different hydrogeological conditions of the subsystems, the degrees to which human activities affect the subsystems are also diverse. In order to evaluate the influence of human activities on each subsystem, the first and second aquifer with relatively poor water quality were chosen to be the evaluating positions, based on the data of groundwater sampled in September, 2011. With respect to human activities affect index such as total hardness, TDS, sulfate and ammonium, variation coefficient methods were used to calculate the weight of each index. Then scores were obtained for each index with national standard as reference, and superposition calculations were used to gain comprehensive scores, finally the groundwater quality conditions were evaluated. Contrast analyses were used to evaluate the incidence of human activities with groundwater subsystems as evaluation unit and water quality partitions as evaluation factors. The results indicate that the influence of human activities on the first aquifer is greater than that of the second aquifer, the Yongding river groundwater subsystems and the Chaobai river groundwater subsystems are affected more than other groundwater subsystems.

  12. Robust, non-invasive methods for metering groundwater well extraction in remote environments

    Science.gov (United States)

    Bulovic, Nevenka; Keir, Greg; McIntyre, Neil

    2017-04-01

    Quantifying the rate of extraction from groundwater wells can be essential for regional scale groundwater management and impact assessment. This is especially the case in regions heavily dependent on groundwater such as the semi-arid Surat and Bowen Basins in Queensland, Australia. Of the 30 000+ groundwater wells in this area, the majority of which are used for stock watering and domestic purposes, almost none have flow metering devices installed. As part of a research project to estimate regional groundwater extraction, we have undertaken a small scale flow metering program on a selected set of wells. Conventional in-line flow meters were unsuitable for our project, as both non-invasiveness and adaptability / suitability to a variety of discharge pipe characteristics was critical. We describe the use of two metering technologies not widely used in groundwater applications, non-invasive, clamp-on ultrasonic transit time flow meters and tipping bucket flow meters, as semi-permanent installations on discharge pipes of various artesian and sub-artesian groundwater wells. We present examples of detailed extraction rate time-series, which are of particular value in developing predictive models of water well extraction in data limited areas where water use dynamics and drivers are poorly understood. We conclude by discussing future project trajectories, which include expansion of the monitoring network through development of novel metering techniques and telemetry across large areas of poor connectivity.

  13. Enhancing Student Learning in and out of the Classroom with Electronic Teaching and Study Aids Built Around Interactive Groundwater Visualization Software

    Science.gov (United States)

    Fish, W.; McKillip, M.; Li, S.

    2003-12-01

    Advances in electronic resources allow more realistic student problems, increased student engagement and self learning, and the use of interactive, exploratory learning. We are using a sophisticated yet easy-to-use groundwater modeling and visualization program (Interactive Groundwater, IGW, Li and Liu: www.egr.msu.edu/ ˜lishug/research/igw) to build packages of innovative tools for instructors and students. Equipped with an advanced graphical interface, IGW allows interactive visualization and manipulation of complex, multidimensional subsurface systems including hydrology, contaminant transport and assessment of contaminated sites. Two principle product packages are the Graphical Teaching Aid (GTA) and the Student Learning Exercise (SLE), developed as part of the NSF-supported Virtual Interactive Remediation in the Groundwater Environment (VIRGE). A GTA is a classroom-presentation guide that includes text materials for the instructor as well as supporting electronic IGW files for interactive graphical demonstrations and discussions in the classroom. Text files include a conceptual outline and a list of principles to be examined in the lecture as well as a flexible script punctuated and illustrated throughout by use of IGW as a highly interactive "electronic chalkboard". The thorough text guides the instructor in the effective use of IGW, suggests ideas to engage student interaction, and provides ways to tailor the interactive presentation to student needs. An SLE complements the GTA as an interactive exercise to engage students in discovery learning. As with GTAs, SLEs are designed for specific levels of classes (undergraduate or graduate) and specific populations (non-technical, science, or engineering majors). Text files (background and instruction) and IGW files (for problem visualization, interactive manipulation and solution) are provided. The SLEs include interactive computer-based exercises ranging from introductory investigations to extensive, open

  14. Sherlock: A Coached Practice Environment for an Electronics Troubleshooting Job.

    Science.gov (United States)

    Lesgold, Alan; And Others

    "Sherlock" is a computer-based, supported practice environment for a complex troubleshooting job in Air Force electronics. The program was developed to raise the level of troubleshooting knowledge of avionics technicians. This describes the training problem for which Sherlock was developed, the principles behind its development, and its…

  15. Integrating Sustainability in a PBL Environment for Electronics Engineering

    DEFF Research Database (Denmark)

    2013-01-01

    in a problem based learning environment. Three electronics engineering project modules were selected as example and empirically supported by constructed interviews with staff and document analysis of selected material. The findings were analysed with a systems approach and presented with reference to three...

  16. Expression and Association Rights of School Employees in Electronic Environments

    Science.gov (United States)

    Bathon, Justin M.

    2012-01-01

    Many of the recent legal decisions regarding public employee expression, particularly in electronic environments, run counter to the culture being facilitated by the Internet. This article uses a legal analysis to examine recent decisions and then considers those legal positions within the context of digital expression. (Contains 2 notes.)

  17. Managing Channels of Distribution Under the Environment of Electronic Commerce

    Institute of Scientific and Technical Information of China (English)

    ZHENG Bing; FENG Yixiong

    2006-01-01

    Business Marketing Management over the Internet has been receiving a "lot of ink" in current periodicals and to a lesser degree in academic literature. Practice changes so rapidly that principles emerging from last month's successes may need revision before they are derived and printed. The emergence of electronic commerce has created a new business paradigm, one that presents marketers with noteworthy opportunities and challenges. Perhaps the greatest impact is in the area of channel management. The top issue for many business-to-business (B2B) firms today is channel conflict. In this paper, we analyze the weakness of traditional place model at first. On the basis of it, we set forth the processes and advantages of direct place and indirect place under the environment of electronic commerce. Then this paper presents that we should develop association net, express net, service net and production net in order to create place advantage under the environment of electronic commerce.

  18. Occurrences of Uranium and Radon-222 in Groundwaters from Various Geological Environments in the Hoengseong Area

    Science.gov (United States)

    Jeong, Chan Ho; Lee, Yu Jin; Lee, Young Cheon; Choi, Hyeon Young; Yang, Jae Ha

    2016-04-01

    Groundwaters in granite, gneiss, and two-mica granite formations, including faults, in the Hoengseong area are examined to determine the relationship between their uranium and radon-222 contents and rock types. The chemical compositions of 38 groundwater samples and four surface water samples collected in the study area were analyzed. Sixteen of the samples showing high uranium and radon-222 contents were repeatedly analyzed. Surface radioactivities were measured at 30 points. The uranium and radon-222 concentrations in the groundwater samples were in the ranges of 0.02-49.3 μg/L and 20-906 Bq/L, respectively. Four samples for uranium and 35 samples for radon had concentrations exceeding the alternative maximum contaminant level of the US EPA. The chemical compositions of groundwaters indicated Ca(Na)-HCO3 and Ca(Na)-NO3(HCO3+Cl) types. The pH values ranged from 5.71 to 8.66. High uranium and radon-222 contents in the groundwaters occurred mainly at the boundary between granite and gneiss, and in the granite area. The occurrence of uranium did not show any distinct relationship to that of radon-222. The radon-222, an inert gas, appeared to be dissolved in the groundwater of the aquifer after wide diffusion along rock fractures, having been derived from the decay of uranium in underground rocks. The results in this study indicate that groundwater of neutral or weakly alkaline pH, under oxidizing conditions and with a high bicarbonate content is favorable for the dissolution of uranium and uranium complexes such as uranyl or uranyl-carbonate. Key word: uranium, radon-222, geological boundary, groundwater, chemical characteristics, surface radioactivity

  19. Climate change impact on freshwater resources in a deltaic environment: A groundwater modeling study

    Science.gov (United States)

    Matiatos, Ioannis; Alexopoulos, John D.; Panagopoulos, Andreas; Nastos, Panagiotis T.; Kotsopoulos, Spyros; Ghionis, George; Poulos, Serafim

    2016-04-01

    Climate change is expected to affect the hydrological cycle, altering seawater level and groundwater recharge to coastal aquifers with various other associated impacts on natural ecosystems and human activities. As the sustainable use of groundwater resources is a great challenge for many countries in the world, groundwater modeling has become a very useful and well established tool for studying groundwater management problems. This study investigates the impacts of climate change on the groundwater of the deltaic plain of River Pinios (Central Greece). Geophysical data processing indicates that the phreatic aquifer extends mainly in the central and northern parts of the region. A one-layer transient groundwater flow and contaminant mass transport model of the aquifer system is calibrated and validated. Impacts of climate change were evaluated by incorporating the estimated recharge input and sea level change of different future scenarios within the simulation models. The most noticeable and consistent result of the climate change impact simulations is a prominent sea water intrusion in the coastal aquifer mainly as a result of sea level change which underlines the need for a more effective planning of environmental measures.

  20. Combining Wireless Sensor Networks and Groundwater Transport Models: Protocol and Model Development in a Simulative Environment

    Science.gov (United States)

    Barnhart, K.; Urteaga, I.; Han, Q.; Porta, L.; Jayasumana, A.; Illangasekare, T.

    2007-12-01

    Groundwater transport modeling is intended to aid in remediation processes by providing prediction of plume location and by helping to bridge data gaps in the typically undersampled subsurface environment. Increased availability of computer resources has made computer-based transport models almost ubiquitous in calculating health risks, determining cleanup strategies, guiding environmental regulatory policy, and in determining culpable parties in lawsuits. Despite their broad use, very few studies exist which verify model correctness or even usefulness, and those that have shown significant discrepancies between predicted and actual results. Better predictions can only be gained from additional and higher quality data, but this is an expensive proposition using current sampling techniques. A promising technology is the use of wireless sensor networks (WSNs) which are comprised of wireless nodes (motes) coupled to in-situ sensors that are capable of measuring hydrological parameters. As the motes are typically battery powered, power consumption is a major concern in routing algorithms. By supplying predictions about the direction and arrival time of the contaminant, the application-driven routing protocol would then become more efficient. A symbiotic relationship then exists between the WSN, which is supplying the data to calibrate the transport model, and the model, which may be supplying predictive information to the WSN for optimum monitoring performance. Many challenges exist before the above can be realized: WSN protocols must mature, as must sensor technology, and inverse models and tools must be developed for integration into the system. As current model calibration, even automatic calibration, still often requires manual tweaking of calibration parameters, implementing this in a real-time closed-loop process may require significant work. Based on insights from a previous proof-of-concept intermediate-scale tank experiment, we are developing the models, tools

  1. Electronic Components and Circuits for Extreme Temperature Environments

    Science.gov (United States)

    Patterson, Richard L.; Hammoud, Ahmad; Dickman, John E.; Gerber, Scott

    2003-01-01

    Planetary exploration missions and deep space probes require electrical power management and control systems that are capable of efficient and reliable operation in very low temperature environments. Presently, spacecraft operating in the cold environment of deep space carry a large number of radioisotope heating units in order to maintain the surrounding temperature of the on-board electronics at approximately 20 C. Electronics capable of operation at cryogenic temperatures will not only tolerate the hostile environment of deep space but also reduce system size and weight by eliminating or reducing the radioisotope heating units and their associate structures; thereby reducing system development as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from better behavior and tolerance in the electrical and thermal properties of semiconductor and dielectric materials at low temperatures. The Low Temperature Electronics Program at the NASA Glenn Research Center focuses on research and development of electrical components, circuits, and systems suitable for applications in the aerospace environment and deep space exploration missions. Research is being conducted on devices and systems for reliable use down to cryogenic temperatures. Some of the commercial-off-the-shelf as well as developed components that are being characterized include switching devices, resistors, magnetics, and capacitors. Semiconductor devices and integrated circuits including digital-to-analog and analog-to-digital converters, DC/DC converters, operational amplifiers, and oscillators are also being investigated for potential use in low temperature applications. An overview of the NASA Glenn Research Center Low Temperature Electronic Program will be presented in this paper. A description of the low temperature test facilities along with

  2. Experimental study of CT test on the failure of acrylate spray-applied waterproof layer in the groundwater environment

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this study the computerized tomography (CT) was first used to quantitatively analyze the failure of acrylate spray-applied waterproof membrane in the groundwater environment. The results of the CT tests show that it is feasible to use the CT to quantitatively analyze the failure of the waterproof membrane and the CT method has the advantages of speediness and accuracy that can eliminate the fussy operation process in routine tests. The main conclusions summarized from the study are as follows. First, there are two combined-indexes that can be used to decide the failure of the spray-on waterproof layer: one is that the reduced percentage of the CT number of the spray-on waterproof layer is less than 40.0% and the other is that the variance of the CT number decreases first and then increases. Second, the applicability for the spray-on waterproof layer in the groundwater environment is the SO 24-concentration ≤ 1%, the Cl-concentration ≤ 7.5% and the pH value ≤ 12.0 of the groundwater, respectively.

  3. A Deterministic Transport Code for Space Environment Electrons

    Science.gov (United States)

    Nealy, John E.; Chang, C. K.; Norman, Ryan B.; Blattnig, Steve R.; Badavi, Francis F.; Adamczyk, Anne M.

    2010-01-01

    A deterministic computational procedure has been developed to describe transport of space environment electrons in various shield media. This code is an upgrade and extension of an earlier electron code. Whereas the former code was formulated on the basis of parametric functions derived from limited laboratory data, the present code utilizes well established theoretical representations to describe the relevant interactions and transport processes. The shield material specification has been made more general, as have the pertinent cross sections. A combined mean free path and average trajectory approach has been used in the transport formalism. Comparisons with Monte Carlo calculations are presented.

  4. Improved water resource management for a highly complex environment using three-dimensional groundwater modelling

    Science.gov (United States)

    Moeck, Christian; Affolter, Annette; Radny, Dirk; Dressmann, Horst; Auckenthaler, Adrian; Huggenberger, Peter; Schirmer, Mario

    2017-08-01

    A three-dimensional groundwater model was used to improve water resource management for a study area in north-west Switzerland, where drinking-water production is close to former landfills and industrial areas. To avoid drinking-water contamination, artificial groundwater recharge with surface water is used to create a hydraulic barrier between the contaminated sites and drinking-water extraction wells. The model was used for simulating existing and proposed water management strategies as a tool to ensure the utmost security for drinking water. A systematic evaluation of the flow direction between existing observation points using a developed three-point estimation method for a large number of scenarios was carried out. It is demonstrated that systematically applying the developed methodology helps to identify vulnerable locations which are sensitive to changing boundary conditions such as those arising from changes to artificial groundwater recharge rates. At these locations, additional investigations and protection are required. The presented integrated approach, using the groundwater flow direction between observation points, can be easily transferred to a variety of hydrological settings to systematically evaluate groundwater modelling scenarios.

  5. Behavioral response to contamination risk information in a spatially explicit groundwater environment: Experimental evidence

    Science.gov (United States)

    Li, Jingyuan; Michael, Holly A.; Duke, Joshua M.; Messer, Kent D.; Suter, Jordan F.

    2014-08-01

    This paper assesses the effectiveness of aquifer monitoring information in achieving more sustainable use of a groundwater resource in the absence of management policy. Groundwater user behavior in the face of an irreversible contamination threat is studied by applying methods of experimental economics to scenarios that combine a physics-based, spatially explicit, numerical groundwater model with different representations of information about an aquifer and its risk of contamination. The results suggest that the threat of catastrophic contamination affects pumping decisions: pumping is significantly reduced in experiments where contamination is possible compared to those where pumping cost is the only factor discouraging groundwater use. The level of information about the state of the aquifer also affects extraction behavior. Pumping rates differ when information that synthesizes data on aquifer conditions (a "risk gauge") is provided, despite invariant underlying economic incentives, and this result does not depend on whether the risk information is location-specific or from a whole aquifer perspective. Interestingly, users increase pumping when the risk gauge signals good aquifer status compared to a no-gauge treatment. When the gauge suggests impending contamination, however, pumping declines significantly, resulting in a lower probability of contamination. The study suggests that providing relatively simple aquifer condition guidance derived from monitoring data can lead to more sustainable use of groundwater resources.

  6. High-Performance, Radiation-Hardened Electronics for Space Environments

    Science.gov (United States)

    Keys, Andrew S.; Watson, Michael D.; Frazier, Donald O.; Adams, James H.; Johnson, Michael A.; Kolawa, Elizabeth A.

    2007-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project endeavors to advance the current state-of-the-art in high-performance, radiation-hardened electronics and processors, ensuring successful performance of space systems required to operate within extreme radiation and temperature environments. Because RHESE is a project within the Exploration Technology Development Program (ETDP), RHESE's primary customers will be the human and robotic missions being developed by NASA's Exploration Systems Mission Directorate (ESMD) in partial fulfillment of the Vision for Space Exploration. Benefits are also anticipated for NASA's science missions to planetary and deep-space destinations. As a technology development effort, RHESE provides a broad-scoped, full spectrum of approaches to environmentally harden space electronics, including new materials, advanced design processes, reconfigurable hardware techniques, and software modeling of the radiation environment. The RHESE sub-project tasks are: SelfReconfigurable Electronics for Extreme Environments, Radiation Effects Predictive Modeling, Radiation Hardened Memory, Single Event Effects (SEE) Immune Reconfigurable Field Programmable Gate Array (FPGA) (SIRF), Radiation Hardening by Software, Radiation Hardened High Performance Processors (HPP), Reconfigurable Computing, Low Temperature Tolerant MEMS by Design, and Silicon-Germanium (SiGe) Integrated Electronics for Extreme Environments. These nine sub-project tasks are managed by technical leads as located across five different NASA field centers, including Ames Research Center, Goddard Space Flight Center, the Jet Propulsion Laboratory, Langley Research Center, and Marshall Space Flight Center. The overall RHESE integrated project management responsibility resides with NASA's Marshall Space Flight Center (MSFC). Initial technology development emphasis within RHESE focuses on the hardening of Field Programmable Gate Arrays (FPGA)s and Field Programmable Analog

  7. Nanobiotechnology in energy, environment and electronics methods and applications

    CERN Document Server

    Nicolini, Claudio

    2015-01-01

    Introduction: Present Challenges and Future Solutions via Nanotechnology for Electronics, Environment and Energy; Claudio NicoliniPart A: MethodsInfluence of Chromosome Translocation on Yeast Life Span: Implications for Long-Term Industrial Biofermentation; Jason Sims, Dmitri Nikitin, and Carlo V. BruschiPulsed Power Nanotechnologies for Disintegration and Breaking Up of Refractory Precious Metals Ores; Valentin A. Chanturiya and Igor Zh. BuninModeling of Software Sensors in Bioprocess; Luca Belmonte and Claudio NicoliniN

  8. An optimised PCR/T-RFLP fingerprinting approach for the investigation of protistan communities in groundwater environments.

    Science.gov (United States)

    Euringer, Kathrin; Lueders, Tillmann

    2008-10-01

    Due to the scarcity or complete absence of higher organisms, protists may represent an important higher trophic level (above Prokaryotes) in the food webs of groundwater habitats. Nevertheless, the importance of aquifer protists, especially in contaminated groundwater environments, is poorly understood. Partly, this may be due to a lack of adequate PCR and fingerprinting approaches for protists in aquifers, which can be considered low in protistan or high in non-target rRNA gene copy numbers. Therefore, we have validated the suitability of distinct eukaryote-targeted primer pairs and restriction endonucleases for T-RFLP fingerprinting of protistan communities. By in silico predictions, and by fingerprinting, cloning and sequencing of microeukaryote amplicons from hydrocarbon-contaminated aquifer sediment DNA, we show that the Euk20f/Euk516r primer set in combination with Bsh1236I digestion is best suited for the recovery of diverse protistan 18S rRNA lineages. In contrast to other tested primer sets, a preferred recovery of fungal and archaeal non-target amplicons was not observed. In summary, we present an optimised microeukaryote-targeted PCR/T-RFLP fingerprinting approach which may be of value for the characterisation of protistan communities in groundwater and other habitats.

  9. Quantity and quality of groundwater discharge in a hypersaline lake environment

    Science.gov (United States)

    Anderson, R.B.; Naftz, D.L.; Day-Lewis, F. D.; Henderson, R.D.; Rosenberry, D.O.; Stolp, B.J.; Jewell, P.

    2014-01-01

    Geophysical and geochemical surveys were conducted to understand groundwater discharge to Great Salt Lake (GSL) and assess the potential significance of groundwater discharge as a source of selenium (Se). Continuous resistivity profiling (CRP) focusing below the sediment/water interface and fiber-optic distributed temperature sensing (FO-DTS) surveys were conducted along the south shore of GSL. FO-DTS surveys identified persistent cold-water temperature anomalies at 10 separate locations. Seepage measurements were conducted at 17 sites (mean seepage rate = 0.8 cm/day). High resistivity anomalies identified by the CRP survey were likely a mirabilite (Na2SO4·10H2O) salt layer acting as a semi-confining layer for the shallow groundwater below the south shore of the lake. Positive seepage rates measured along the near-shore areas of GSL indicate that a ∼1-m thick oolitic sand overlying the mirabilite layer is likely acting as a shallow, unconfined aquifer. Using the average seepage rate of 0.8 cm/day over an area of 1.6 km2, an annual Se mass loading to GSL of 23.5 kg was estimated. Determination of R/Ra values (calculated 3He/4He ratio over the present-day atmospheric 3He/4He ratio) 34S and δ18O isotopic values in samples of dissolved sulfate from the shallow groundwater below the mirabilite are almost identical to the isotopic signature of the mirabilite core material. The saturation index calculated for groundwater samples using PHREEQC indicates the water is at equilibrium with mirabilite. Water samples collected from GSL immediately off shore contained Se concentrations that were 3–4 times higher than other sampling sites >25 km offshore from the study site and may be originating from less saline groundwater seeps mixing with the more saline water from GSL. Additional evidence for mixing with near shore seeps is found in the δD and δ18O isotopic values and Br:Cl ratios. Geochemical modeling for a water sample collected in the vicinity of the study area

  10. Response of the microbial community to seasonal groundwater level fluctuations in petroleum hydrocarbon-contaminated groundwater.

    Science.gov (United States)

    Zhou, Ai-xia; Zhang, Yu-ling; Dong, Tian-zi; Lin, Xue-yu; Su, Xiao-si

    2015-07-01

    The effects of seasonal groundwater level fluctuations on the contamination characteristics of total petroleum hydrocarbons (TPH) in soils, groundwater, and the microbial community were investigated at a typical petrochemical site in northern China. The measurements of groundwater and soil at different depths showed that significant TPH residue was present in the soil in this study area, especially in the vicinity of the pollution source, where TPH concentrations were up to 2600 mg kg(-1). The TPH concentration in the groundwater fluctuated seasonally, and the maximum variation was 0.8 mg L(-1). The highest TPH concentrations were detected in the silty clay layer and lied in the groundwater level fluctuation zones. The groundwater could reach previously contaminated areas in the soil, leading to higher groundwater TPH concentrations as TPH leaches into the groundwater. The coincident variation of the electron acceptors and TPH concentration with groundwater-table fluctuations affected the microbial communities in groundwater. The microbial community structure was significantly different between the wet and dry seasons. The canonical correspondence analysis (CCA) results showed that in the wet season, TPH, NO3(-), Fe(2+), TMn, S(2-), and HCO3(-) were the major factors correlating the microbial community. A significant increase in abundance of operational taxonomic unit J1 (97% similar to Dechloromonas aromatica sp.) was also observed in wet season conditions, indicating an intense denitrifying activity in the wet season environment. In the dry season, due to weak groundwater level fluctuations and low temperature of groundwater, the microbial activity was weak. But iron and sulfate-reducing were also detected in dry season at this site. As a whole, groundwater-table fluctuations would affect the distribution, transport, and biodegradation of the contaminants. These results may be valuable for the control and remediation of soil and groundwater pollution at this site

  11. Subsurface Biogeochemical Heterogeneity (Field-scale removal of U(VI) from groundwater in an alluvial aquifer by electron donor amendment)

    Energy Technology Data Exchange (ETDEWEB)

    Long, Philip E.; Lovley, Derek R.; N' Guessan, A. L.; Nevin, Kelly; Resch, C. T.; Arntzen, Evan; Druhan, Jenny; Peacock, Aaron; Baldwin, Brett; Dayvault, Dick; Holmes, Dawn; Williams, Ken; Hubbard, Susan; Yabusaki, Steve; Fang, Yilin; White, D. C.; Komlos, John; Jaffe, Peter

    2006-06-01

    Determine if biostimulation of alluvial aquifers by electron donor amendment can effectively remove U(VI) from groundwater at the field scale. Uranium contamination in groundwater is a significant problem at several DOE sites. In this project, the possibility of accelerating bioreduction of U(VI) to U(IV) as a means of decreasing U(VI) concentrations in groundwater is directly addressed by conducting a series of field-scale experiments. Scientific goals include demonstrating the quantitative linkage between microbial activity and U loss from groundwater and relating the dominant terminal electron accepting processes to the rate of U loss. The project is currently focused on understanding the mechanisms for unexpected long-term ({approx}2 years) removal of U after stopping electron donor amendment. Results obtained in the project successfully position DOE and others to apply biostimulation broadly to U contamination in alluvial aquifers.

  12. Charge Cards: Risk Management in the Contemporary Electronic Environment

    Directory of Open Access Journals (Sweden)

    Aleksandar Čudan

    2010-06-01

    Full Text Available Information technology must be a tool which facilitates business operations rather than a hindrance to achieving business goals. Applicative solutions have to provide required performances, risk control, simple integration and necessary flexibility for successful implementation. Contemporary information tools offer attractive features, but they are also a specific implementation challenge for management structures in the financial sector. In the new setting of information challenge, business persons must be far better technologically trained on the one hand, while on the other, the new technology must become much more human-oriented. The aim of such application is to define risk control in the approach to information technologies and organise risk protection techniques. The management of financial institutions must permanently reconsider, revise and update the risk management plan. In this, it is essential to establish the risks prevailing in the total integrated electronic trade environment. In the electronic environment, controls must be primarily preventive by nature. Numerous and varied potential threats endangering information systems, especially those that can be qualified as crime, unequivocally impose the need to build an adequate system for information system protection. Consequences are as unknown as the directions and possibilities of establishing completely new directions, or a new and less well-known payment facility such as digital money, i.e. charge cards. Only future will show whether it is the end of money as we know it, or the revolution of a new payment tool. It is a fact that the electronic market is here to stay.

  13. Atrazine and terbutryn degradation in deposits from groundwater environment within the boreal region in Lahti, Finland.

    Science.gov (United States)

    Talja, K Marja; Kaukonen, Sanna; Kilpi-Koski, Johanna; Malin, Ismo; Kairesalo, Timo; Romantschuk, Martin; Tuominen, Jari; Kontro, Merja H

    2008-12-24

    The degradation of pesticides atrazine and terbutryn was investigated under aerobic and anaerobic conditions in the northern boreal region subsurface deposits and sterilized controls from the depths of 6.3-21.0 m below the surface and 1.2-16.9 m below the groundwater table. During 1.3-1.7 years of laboratory incubation, atrazine degradation under aerobic conditions varied from rapid (half-live 38 days) to no degradation. Anaerobically, atrazine half-lives were 430-829 days. Organic matter, nitrogen, and lead in deposits correlated positively with the atrazine concentration in groundwater. Aerobic and anaerobic terbutryn half-lives were 193-644 and 266-400 days, respectively. Microbial aerobic atrazine and terbutryn degradation was confirmed in the deep deposits near the water table. Under aerobic conditions, the high amounts of Cr, Mn, Ni, and Zn in deposits decreased the chemical degradation of terbutryn.

  14. Artificial groundwater recharge as integral part of a water resources system in a humid environment

    Science.gov (United States)

    Kupfersberger, Hans; Stadler, Hermann

    2010-05-01

    In Graz, Austria, artificial groundwater recharge has been operated as an integral part of the drinking water supply system for more than thirty years. About 180 l/s of high quality water from pristine creeks (i.e. no pre-treatment necessary) are infiltrated via sand and lawn basins and infiltration trenches into two phreatic aquifers to sustain the extraction of approximately 400 l/s. The remaining third of drinking water for roughly 300.000 people is provided by a remote supply line from the East alpine karst region Hochschwab. By this threefold model the water supply system is less vulnerable to external conditions. In the early 1980's the infiltration devices were also designed as a hydraulic barrier against riverbank infiltration from the river Mur, which at that time showed seriously impaired water quality due to upstream paper mills. This resulted into high iron and manganese groundwater concentrations which lead to clogging of the pumping wells. These problems have been eliminated in the meantime due to the onsite purification of paper mill effluents and the construction of many waste water treatment plants. The recharge system has recently been thoroughly examined to optimize the operation of groundwater recharge and to provide a basis for further extension. The investigations included (i) field experiments and laboratory analyses to improve the trade off between infiltration rate and elimination capacities of the sand filter basins' top layer, (ii) numerical groundwater modelling to compute the recovery rate of the recharged water, the composition of the origin of the pumped water, emergency scenarios due to the failure of system parts, the transient capture zones of the withdrawal wells and the coordination of recharge and withdrawal and (iii) development of an online monitoring setup combined with a decision support system to guarantee reliable functioning of the entire structure. Additionally, the depreciation, maintenance and operation costs of the

  15. Evaluation of Cr in ophiolite and groundwater and its potential to contaminate the environment in SE of Birjand

    Directory of Open Access Journals (Sweden)

    Zahra Khaledi

    2012-10-01

    Full Text Available The presence of Cr(VI in groundwater resources is governed by pH and Eh of water and its compounds are generally soluble and have more toxicicity and mobility in oxidizing environments. In this article, the Cr concentration in ophiolite units, in sediments, and in groundwater resources, and also its potential to contaminate the environment have been investigated in southeast of Birjand. During sampling, 17 water samples (2 rain water samples and 15 groundwater samples, and 8 sediment samples were collected. The concentrations of cations (major cations and Cr and anions in water samples were measured at Ottawa University, Canada using IC and ICP-AES methods, respectively. Cr concentrations of sediments were measured using XRF, and concentrations of Cr in collected Selective Sequential Extraction (SSE fractions were measured using Atomic Absorption (AA at Ferdowsi University of Mashhad, Iran. The average Cr concentrations in sediments and water resources are 627 and 0.026 ppm, respectively. According to the pH of sediments and Eh-pH of water samples, the Cr in water resources is as Cr(VI. Furthermore, the results of SSE show that the majority of Cr was found with residual matter, attached to the iron and manganese oxides, bound to carbonates, organic matter, and the soluble fractions, respectively. The hydrogeochemical properties of water resources show that the average values of EC, TDS and pH are 509 mg/l, 1045 µs/cm and 8.1, respectively, and the concentrations of Cl-, Na+, Mg2+ and SO42- ions are higher than the levels of WHO and Iran National Standard (1053. According to the WQI classification, while 20 percent of the water resources have excellent quality, 53 percent show good quality and 20 percent of water resources are poor in quality.

  16. Electronic commerce environment: (Economic Drivers and Security Issues

    Directory of Open Access Journals (Sweden)

    Davuluri Nageswara Rao

    2014-02-01

    Full Text Available This paper analyzes the development situation and a lot of issues in E-commerce at present, inc luding trade safety issue and pertains to trading in goods and services through the electronic medium.Overa ll, the study provides improv edunderstanding of a growing awareness among the business community in global about the opportunities offered by e-commerce. This artic le is based on a literature review that e mphasizes the need for increased security and privacy measures in current E-commerce environment.

  17. ELECTRONIC COMMERCE ENVIRONMENT: (ECONOMIC DRIVERS AND SECURITY ISSUES

    Directory of Open Access Journals (Sweden)

    Davuluri Nageswara Rao

    2015-11-01

    Full Text Available This paper analyzes the development situation and a lot of issues in E-commerce at present, including trade safety issue and pertains to trading in goods and services through the electronic medium. Overall, the study provides improved understanding of a growing awareness among the business community in global about the opportunities offered by e-commerce. This article is based on a literature review that emphasizes the need for increased security and privacy measures in current E-commerce environment.

  18. Social relationships in an electronic environment. Cultural factors and variables

    Directory of Open Access Journals (Sweden)

    Carmine CLEMENTE

    2015-06-01

    Full Text Available Within certain cultural and social limits, some behaviours linked to the use of new technology, gaming, physical exercise or work are useful practices with a positive social value for both individuals and society. As these practices are commonly and socially accepted, the trend is to underestimate the risks and not to perceive them as deviances even when they start to be compulsive. This paper focuses on the concept of new non-substance addictions and on how some social factors influence, on the one side, this new interaction between man and technology and, on the other side, social relationships in the electronic environment.

  19. Co-contamination of arsenic and fluoride in the groundwater of unconsolidated aquifers under reducing environments.

    Science.gov (United States)

    Kim, Seok-Hwi; Kim, Kangjoo; Ko, Kyung-Seok; Kim, Yeongkyoo; Lee, Kwang-Sik

    2012-05-01

    The co-contamination of arsenic (As) and fluoride (F(-)) in shallow aquifers is frequently observed worldwide, and the correlations between those contaminants are different according to the redox conditions. This study geochemically explores the reasons for the co-contamination and for the redox-dependent correlations by investigating the groundwater of an alluvial aquifer in Korea. Geochemical signatures of the groundwater in the study area show that the As concentrations are enriched by the reductive dissolution of Fe-(hydr)oxides, and the correlations between As and F(-) concentrations are poor comparatively to those observed in the oxidizing aquifers. However, F(-) concentrations are strongly dependent on pH. Desorption/adsorption experiments using raw soils and citrate-bicarbonate-dithionite treated soils indicated that Fe-(hydr)oxides are the important As and F(-) hosts causing the co-contamination phenomenon. The weaker correlation between F(-) and As in reducing aquifers is likely to be associated with sulfate reduction, which removes As from groundwater without changing the F(-) concentration. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. In situ Bioreduction of Uranium (VI) in Groundwater and Sediments with Edible Oil as the Electron Donor

    Science.gov (United States)

    Wu, W.; Watson, D. B.; Mehlhorn, T.; Zhang, G.; Earles, J.; Lowe, K.; Phillips, J.; Boyanov, M.; Kemner, K. M.; Schadt, C. W.; Brooks, S. C.; Criddle, C.; Jardine, P.

    2009-12-01

    In situ bioremediation of a uranium-contaminated aquifer was conducted at the US DOE Environmental Remediation Sciences Program (ERSP) Integrated Field Research Challenge (IFRC) site, in Oak Ridge, TN. Edible oil was tested as a slow-release electron donor for microbially mediated U (VI) reduction. Uranium contaminated sediments from the site were used in laboratory microcosm tests to study the feasibility of using this electron donor under anaerobic, ambient temperature conditions. Parallel microcosms were established using ethanol as electron donor for comparison. The tests also examined the impact of sulfate concentrations on U (VI) reduction. The oil was degraded by indigenous microorganisms with acetate as a major product but at a much slower rate than ethanol. The rapid removal of U (VI) from the aqueous phase occurred concurrently with acetate production and sulfate reduction. Initial U(VI) concentration in the aqueous phase increased with increased sulfate concentration (1 vs. 5 mM), likely due to U(VI) desorption from the solid phase, but more U(VI) was reduced with higher initial sulfate level. Finally, the bioreaction in microcosms progressed to methanogenesis. Subsequently, a field test with the edible oil was conducted in a highly permeable gravelly layer (hydraulic conductivity 0.076 cm/sec). Groundwater at the site contained 5-6 μM U; 1.0-1.2 mM sulfate; 3-4 mM Ca; pH 6.8. Diluted emulsified oil (20% solution) was injected into three injection wells within 2 hrs. Geochemical analysis of site groundwater demonstrated the sequential reduction of nitrate, Mn, Fe(III) and sulfate. Transient accumulation of acetate was observed as an intermediate in the oil degradation. Reduction and removal of uranium from groundwater was observed in all wells connected to the injection wells after 2-4 weeks. Uranium concentrations in groundwater were reduced to below 0.126 μM (EPA drinking water standard), at some well locations. Rebound of U in groundwater was

  1. The Challenges of Becoming Tutors at Electronic Environments

    Directory of Open Access Journals (Sweden)

    María Eugenia López Hurtado

    2014-07-01

    Full Text Available This paper presents a research report of my own experience as a tutor in electronic environments which I have accumulated throughout the guidance for English learners of basic level at a public university. This article looks for illustrating the researcher's own perceptions and challenges as becoming an e-tutor. Therefore, I will introduce an overview of studies and experiences that address this issue in international contexts, and then I will refer to my own experience where I describe the roles that emerged while I was administrating and delivering e- learning pedagogical experiences such as an exploration of some skills and learning activities carried out in an English course; this description embraces three different stages (before, during and after of implementation. Subsequently, some discussion of the results is provided gathered from the research instruments I used. Finally, some conclusions and suggestions are provided in regards to the research question of the study, its outcomes on how tutors' challenges shape tutor's roles in electronic environments.

  2. In situ bioremediation of nitrate and perchlorate in vadose zone soil for groundwater protection using gaseous electron donor injection technology.

    Science.gov (United States)

    Evans, Patrick J; Trute, Mary M

    2006-12-01

    When present in the vadose zone, potentially toxic nitrate and perchlorate anions can be persistent sources of groundwater contamination. Gaseous electron donor injection technology (GEDIT), an anaerobic variation of petroleum hydrocarbon bioventing, involves injecting electron donor gases, such as hydrogen or ethyl acetate, into the vadose zone, to stimulate biodegradation of nitrate and perchlorate. Laboratory microcosm studies demonstrated that hydrogen and ethanol promoted nitrate and perchlorate reduction in vadose zone soil and that moisture content was an important factor. Column studies demonstrated that transport of particular electron donors varied significantly; ethyl acetate and butyraldehyde were transported more rapidly than butyl acetate and ethanol. Nitrate removal in the column studies, up to 100%, was best promoted by ethyl acetate. Up to 39% perchlorate removal was achieved with ethanol and was limited by insufficient incubation time. The results demonstrate that GEDIT is a promising remediation technology warranting further validation.

  3. Re-Configurable Electronics Characterization under Extreme Thermal Environment

    Science.gov (United States)

    Stoica, Adrian; Lacayo, Veronica; Ramesham, Rajeshuni; Keymeulen, Didier; Zebulum, Ricardo; Neff, Joe; Burke, Gary; Daud, Taher

    2005-01-01

    The need for reconfigurable electronics is driven by requirements to survive longer missions and harsher environments. It is possible to compensate for degradations in Extreme Environments (EE). EE has effect on electronics: circuits are designed to exploit device characteristics and when a certain temperature or radiation range is exceeded the circuit function gradually degrades. It is possible to employ Hardening by reconfiguration (HBR) to mitigate drifts, degradation, or damage on electronic devices in EE by using reconfigurable devices and an adaptive self-reconfiguration of circuit topology. In this manner degraded components can be salvaged, and completely damaged components can be bypassed. The challenge of conventional design is replaced with that of designing a recover process that automatically performs the (re) design in place of the designer. The objective of testing a Digital Signal Processor (DSP) under the extreme temperatures was to determine the lowest temperature at which the DAP can operate. The objective of testing a Xilinx VirtexII Pro FPGA board was to initially find our whether the evaluation board and the FPGA would survive and continue at temperature ranges from -180 C, and 120 C. The Virtex II functioned correctly at the temperatures tested. The next test was done on the GM-C filter building block using the same temperature range as the Virtex II. The current lower and upper limits were shown to be reduced as the temperature gets lower. The device function can be recovered by increasing the Vb from .08V to .85V. The negative and positive saturation voltages increases as the temperature gets higher. The function of the device can be recovered by decreasing the Vb from .8V to around .75V. The next test was performed to test the recovery of the GmC low pass filter through Vb in a filter circuit. The test indicate that bias voltage control adjustment is an efficient mechanism for circuit recovery at extreme temperatures.

  4. Radiation Hardened Electronics Destined For Severe Nuclear Reactor Environments

    Energy Technology Data Exchange (ETDEWEB)

    Holbert, Keith E. [Arizona State Univ., Tempe, AZ (United States); Clark, Lawrence T. [Arizona State Univ., Tempe, AZ (United States)

    2016-02-19

    Post nuclear accident conditions represent a harsh environment for electronics. The full station blackout experience at Fukushima shows the necessity for emergency sensing capabilities in a radiation-enhanced environment. This NEET (Nuclear Energy Enabling Technologies) research project developed radiation hardened by design (RHBD) electronics using commercially available technology that employs commercial off-the-shelf (COTS) devices and present generation circuit fabrication techniques to improve the total ionizing dose (TID) hardness of electronics. Such technology not only has applicability to severe accident conditions but also to facilities throughout the nuclear fuel cycle in which radiation tolerance is required. For example, with TID tolerance to megarads of dose, electronics could be deployed for long-term monitoring, inspection and decontamination missions. The present work has taken a two-pronged approach, specifically, development of both board and application-specific integrated circuit (ASIC) level RHBD techniques. The former path has focused on TID testing of representative microcontroller ICs with embedded flash (eFlash) memory, as well as standalone flash devices that utilize the same fabrication technologies. The standalone flash devices are less complicated, allowing better understanding of the TID response of the crucial circuits. Our TID experiments utilize biased components that are in-situ tested, and in full operation during irradiation. A potential pitfall in the qualification of memory circuits is the lack of rigorous testing of the possible memory states. For this reason, we employ test patterns that include all ones, all zeros, a checkerboard of zeros and ones, an inverse checkerboard, and random data. With experimental evidence of improved radiation response for unbiased versus biased conditions, a demonstration-level board using the COTS devices was constructed. Through a combination of redundancy and power gating, the demonstration

  5. Groundwater in steppe environments: "El Hito" Lagoon wetland as a case of study (Cuenca; Spain)

    Science.gov (United States)

    Sastre-Merlín, A.; Martínez-Pérez, S.; Molina-Navarro, E.

    2012-04-01

    El Hito Lagoon wetland, located in the interfluve of the upper basins of the Cigüela and Záncara rivers (Guadiana Basin, central Spain), configures an important element of geo-environmental heritage of Castilla-LaMancha (Natural Reserve), as well as being an area recognized as Ramsar Site and integrated in the Natura 2000 Network. It has an extension around 290 ha in the periods of maximum flooding and it is embedded in an endorheic basin of 42 Km2. The area that includes it has an arid appearance in a landscape dominated by extensive agriculture, being catalogued as "without aquifers" under its unfavorable geo-hydrological substrate. Thereby, the manifestation of the wetland has been attributed to the simple accumulation of precipitation water in the rainy periods. However, studies to date show the contribution of groundwater to the dynamics of this geo-system, showing how the lake basin behaves itself like a diffuse discharge area of groundwater flow to the endorheic in which it is located. This paper shows the most relevant data to understand the functioning of this wetland of great scientific and environmental importance, as it support interesting halophytic plant communities as well as large number of waterflow and steppe birds.

  6. Geogenic fluoride and arsenic contamination in the groundwater environments in Tanzania

    Science.gov (United States)

    Bhattacharya, Prosun; Lesafi, Fina; Filemon, Regina; Ligate, Fanuel; Ijumulana, Julian; Mtalo, Felix

    2016-04-01

    Adequate, safe and accessible drinking water is an important aspect to human health worldwide. Understanding this importance, the Tanzanian Government has initiated a number of programmes to ensure access to high quality water by the citizens. However, elevated concentration of geochemical pollutants in many drinking water sources pose a serious challenge to water suppliers and users in the country. Fluoride is a widespread drinking water contaminant of geogenic origin occuring in both surface- and groundwater around volcanic mountains and many parts within the East African Rift Valley in regions including Arusha (10 mg/L), Shinyanga (2.9 mg/L) and Singida (1.8 mg/L). An estimated 90% of the population living along the Rift Valley region are affected by dental or skeletal fluorosis and bone crippling because of long term exposure to very high levels of fluoride in drinking water sources. In the mining areas within Lake Victoria basin, groundwater wit elevated concentrations of arsenic has been discovered over an extended area. Most of these geochemical and naturally occurring drinking water pollutants are patchy with uncertainities in their spatial and temporal distribution patterns. The adverse health effects of skin disorder and cancer due to an elevated As concentration are reported from the North Mara gold and Geita mining areas in the Lake Victoria basin. About 30% of the water sources used for drinking in Tanzania exceed the WHO guideline values of fluoride (1.5 mg/L) and arsenic (10 μg/L). There is a scarcity of baseline information on the water quality data especially on geogenic contaminants in the groundwater and surface water as potable sources. This information is crucial in exploring sources of safe drinking water aquifers, associated human health risks of fluoride and arsenic pollution. using Laboratory based studies during the past two decades have shown promising results on the removal of fluoride and arsenic using locally available adsorbent

  7. Reconfiguration of Analog Electronics for Extreme Environments: Problem or Solution?

    Science.gov (United States)

    Stoica, Adrian; Zebulum, Ricardo; Keymeulen, Didier; Guo, Xin

    2005-01-01

    This paper argues in favor of adaptive reconfiguration as a technique to expand the operational envelope of analog electronics for extreme environments (EE). In addition to hardening-by-process and hardening-by-design, "hardening-by-reconfiguration", when applicable, could be used to mitigate drifts, degradation, or damage on electronic devices (chips) in EE, by using re-configurable devices and an adaptive self-reconfiguration of their circuit topology. Conventional circuit design exploits device characteristics within a certain temperature/radiation range; when that is exceeded, the circuit function degrades. On a reconfigurable device, although component parameters change in EE, as long as devices still operate, albeit degraded, a new circuit design, suitable for new parameter values, may be mapped into the reconfigurable structure to recover the initial circuit function. Partly degraded resources are still used, while completely damaged resources are bypassed. Designs suitable for various environmental conditions can be determined prior to operation or can be determined in-situ, by adaptive reconfiguration algorithms running on built-in digital controllers. Laboratory demonstrations of this technique were performed by JPL in several independent experiments in which bulk CMOS reconfigurable devices were exposed to, and degraded by, low temperatures (approx. 196 C), high temperatures (approx.300 C) or radiation (300kRad TID), and then recovered by adaptive reconfiguration using evolutionary search algorithms. Taking this technology from Technology Readiness Level (TRL) 3 to TRL 5 is the target of a current NASA project.

  8. Extreme environments in the critical zone: Linking acidification hazard of acid sulfate soils in mound spring discharge zones to groundwater evolution and mantle degassing.

    Science.gov (United States)

    Shand, Paul; Gotch, Travis; Love, Andrew; Raven, Mark; Priestley, Stacey; Grocke, Sonia

    2016-10-15

    A decrease in flow from the iconic travertine mound springs of the Great Artesian Basin in South Australia has led to the oxidation of hypersulfidic soils and extreme soil acidification, impacting their unique groundwater dependent ecosystems. The build-up of pyrite in these systems occurred over millennia by the discharge of deep artesian sulfate-containing groundwaters through organic-rich subaqueous soils. Rare iron and aluminium hydroxysulfate minerals form thick efflorescences due to high evaporation rates in this arid zone environment, and the oxidised soils pose a significant risk to local aquatic and terrestrial ecosystems. The distribution of extreme acidification hazard is controlled by regional variations in the hydrochemistry of groundwater. Geochemical processes fractionate acidity and alkalinity into separate parts of the discharge zone allowing potentially extreme environments to form locally. Differences in groundwater chemistry in the aquifer along flow pathways towards the spring discharge zone are related to a range of processes including mineral dissolution and redox reactions, which in turn are strongly influenced by degassing of the mantle along deep crustal fractures. There is thus a connection between shallow critical zone ecosystems and deep crustal/mantle processes which ultimately control the formation of hypersulfidic soils and the potential for extreme geochemical environments.

  9. Study on redox zones of petroleum hydrocarbon contamination in groundwater environment

    Science.gov (United States)

    Wen, Ming; Ma, Zhenmin; Jiang, Peng

    2017-03-01

    When the terminal electron acceptors such as O2, NO3-, SO42- were used by microbes to degrade contamination, due to the terminal electron acceptor taking the electronics' capacity are different, the ease of redox reaction is different and it will develop an ordered oxidation reduction zone from the beginning of pollution source to the lower reaches. This research designed a dynamic simulation column experiment which chose limestone pebble as packing medium and the contaminated water in this study was mixture of gasoline#97, diesel#0 and underground water. The redox zones will be divided based on the space distribution status of reducing sensitive material in stimulation column. Research results: The content of electron acceptor in the bottom of stimulation column, like O2, NO3-, SO42-, is lower than that in the top of stimulation column. It develops an ordered redox zone from the bottom to the top, they are respectively the sulfate reduction zone, the nitrate reduction zone and the oxygen reduction zone which will migrate upwards along with time going on.

  10. Evaluation of Using Caged Clams to Monitor Contaminated Groundwater Exposure in the Near-Shore Environment of the Hanford Site 300 Area

    Energy Technology Data Exchange (ETDEWEB)

    Larson, Kyle B.; Poston, Ted M.; Tiller, Brett L.

    2008-01-31

    The Asiatic clam (Corbicula fluminea) has been identified as an indicator species for locating and monitoring contaminated groundwater in the Columbia River. Pacific Northwest National Laboratory conducted a field study to explore the use of caged Asiatic clams to monitor contaminated groundwater upwelling in the 300 Area near-shore environment and assess seasonal differences in uranium uptake in relation to seasonal flow regimes of the Columbia River. Additional objectives included examining the potential effects of uranium accumulation on growth, survival, and tissue condition of the clams. This report documents the field conditions and procedures, laboratory procedures, and statistical analyses used in collecting samples and processing the data. Detailed results are presented and illustrated, followed by a discussion comparing uranium concentrations in Asiatic clams collected at the 300 Area and describing the relationship between river discharge, groundwater indicators, and uranium in clams. Growth and survival, histology, and other sources of environmental variation also are discussed.

  11. Alluvial groundwater recharge estimation in semi-arid environment using remotely sensed data

    Science.gov (United States)

    Coelho, Victor Hugo R.; Montenegro, Suzana; Almeida, Cristiano N.; Silva, Bernardo B.; Oliveira, Leidjane M.; Gusmão, Ana Cláudia V.; Freitas, Emerson S.; Montenegro, Abelardo A. A.

    2017-05-01

    Data limitations on groundwater (GW) recharge over large areas are still a challenge for efficient water resource management, especially in semi-arid regions. Thus, this study seeks to integrate hydrological cycle variables from satellite imagery to estimate the spatial distribution of GW recharge in the Ipanema river basin (IRB), which is located in the State of Pernambuco in Northeast Brazil. Remote sensing data, including monthly maps (2011-2012) of rainfall, runoff and evapotranspiration, are used as input for the water balance method within Geographic Information Systems (GIS). Rainfall data are derived from the TRMM Multi-satellite Precipitation Analysis (TMPA) Version 7 (3B43V7) product and present the same monthly average temporal distributions from 15 rain gauges that are distributed over the study area (r = 0.93 and MAE = 12.7 mm), with annual average estimates of 894.3 (2011) and 300.7 mm (2012). The runoff from the Natural Resources Conservation Service (NRCS) method, which is based on regional soil information and Thematic Mapper (TM) sensor image, represents 29% of the TMPA rainfall that was observed across two years of study. Actual evapotranspiration data, which were provided by the SEBAL application of MODIS images, present annual averages of 1213 (2011) and 1067 (2012) mm. The water balance results reveal a large inter-annual difference in the IRB GW recharge, which is characterized by different rainfall regimes, with averages of 30.4 (2011) and 4.7 (2012) mm year-1. These recharges were mainly observed between January and July in regions with alluvial sediments and highly permeable soils. The GW recharge approach with remote sensing is compared to the WTF (Water Table Fluctuation) method, which is used in an area of alluvium in the IRB. The estimates from these two methods exhibit reliable annual agreement, with average values of 154.6 (WTF) and 124.6 (water balance) mm in 2011. These values correspond to 14.89 and 13.53% of the rainfall that was

  12. Significance of Environmental Variables on Flight Electronics and Design Concerns for Extreme Environments

    Science.gov (United States)

    Hazeli, K.; Kingstedt, O. T.

    2017-05-01

    It is critical to investigate the performance of electronic systems and their components under the environments experienced during proposed missions to improve spacecraft and robotic vehicle functionality and performance in extreme environments.

  13. Geochemical effects on the behavior of LLW radionuclides in soil/groundwater environments

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, K.M.; Sterne, R.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-12-31

    Assessing the migration potential of radionuclides leached from low-level radioactive waste (LLW) and decommissioning sites necessitates information on the effects of sorption and precipitation on the concentrations of dissolved radionuclides. Such an assessment requires that the geochemical processes of aqueous speciation, complexation, oxidation/reduction, and ion exchange be taken into account. The Pacific Northwest National Laboratory (PNNL) is providing technical support to the U.S. Nuclear Regulatory Commission (NRC) for defining the solubility and sorption behavior of radionuclides in soil/ground-water environments associated with engineered cementitious LLW disposal systems and decommissioning sites. Geochemical modeling is being used to predict solubility limits for radionuclides under geochemical conditions associated with these environments. The solubility limits are being used as maximum concentration limits in performance assessment calculations describing the release of contaminants from waste sources. Available data were compiled regarding the sorption potential of radionuclides onto {open_quotes}fresh{close_quotes} cement/concrete where the expected pH of the cement pore waters will equal to or exceed 10. Based on information gleaned from the literature, a list of preferred minimum distribution coefficients (Kd`s) was developed for these radionuclides. The K{sub d} values are specific to the chemical environments associated with the evolution of the compositions of cement/concrete pore waters.

  14. Use of geoelectrical methods in groundwater pollution surveys in a coastal environment

    Science.gov (United States)

    Frohlich, R.K.; Urish, D.W.; Fuller, J.; O'Reilly, M.

    1994-01-01

    Ghyben-Herzberg relation appears to be disturbed in the area of aquifer pollution. This rise in the conductivity boundary is caused by the highly mineralized bottom of the contaminant plume that submerges into the saltwater saturated zone. In the area of high freshwater pollution the groundwater can be subdivided into three layers that show a decrease in resistivity with depth. The formation factor, F, defined as the ratio of bulk aquifer resistivity to pore water resistivity, shows unusually high values between 10 and 12. These high values are unexpected for an unconsolidated sand. Pollution residues are suspected to clog the pores and thus to increase the resistivity. It is possible that iron-oxidizing bacteria and the precipitation of dissolved iron or organic pollutants are the cause of the high values of F. If proven correct, these interesting possibilities could lead to future new applications of the geoelectrical resistivity method in contaminant hydroloy.

  15. Use of geoelectrical methods in groundwater pollution surveys in a coastal environment

    Science.gov (United States)

    Frohlich, Reinhard K.; Urish, Daniel W.; Fuller, James; O'Reilly, Mary

    1994-08-01

    Ghyben-Herzberg relation appears to be disturbed in the area of aquifer pollution. This rise in the conductivity boundary is caused by the highly mineralized bottom of the contaminant plume that submerges into the saltwater saturated zone. In the area of high freshwater pollution the groundwater can be subdivided into three layers that show a decrease in resistivity with depth. The formation factor, F, defined as the ratio of bulk aquifer resistivity to pore water resistivity, shows unusually high values between 10 and 12. These high values are unexpected for an unconsolidated sand. Pollution residues are suspected to clog the pores and thus to increase the resistivity. It is possible that iron-oxidizing bacteria and the precipitation of dissolved iron or organic pollutants are the cause of the high values of F. If proven correct, these interesting possibilities could lead to future new applications of the geoelectrical resistivity method in contaminant hydroloy.

  16. 地下水超采对农业灌溉环境影响及对策%Influence of Groundwater Overdraft on Agricultural Irrigation Environment and Countermeasures

    Institute of Scientific and Technical Information of China (English)

    张玉春

    2014-01-01

    Groundwater overdraft has caused bad effect on irrigation and agricultural environment. We must take effective measures to control and improve the situation. This paper explains the commonly used method for identifying the over exploitation of groundwater, the influence of the over exploitation of groundwater on the irrigation area environment, and puts forward the countermeasure in order to strengthen groundwater management and protection and provide guidance for rational development and utilization of water resources.%地下水超采对灌区农业环境造成不良影响,必须采取有效措施加以控制和改善。介绍判别地下水超采的常用方法,阐述地下水超采对灌区环境的影响,并提出相应的对策,以强化地下水管理与保护,指导水资源的合理开发利用。

  17. Cyanobacteria and cyanotoxins are present in drinking water impoundments and groundwater wells in desert environments.

    Science.gov (United States)

    Chatziefthimiou, Aspassia D; Metcalf, James S; Glover, W Broc; Banack, Sandra A; Dargham, Soha R; Richer, Renee A

    2016-05-01

    Desert environments and drylands experience a drastic scarcity of water resources. To alleviate dependence on freshwater for drinking water needs, countries have invested in infrastructure development of desalination plants. Collectively, the countries of the Arabian Gulf produce 45% of the world's desalinated water, which is stored in dams, mega-reservoirs and secondary house water tanks to secure drinking water beyond daily needs. Improper storage practices of drinking water in impoundments concomitant with increased temperatures and light penetration may promote the growth of cyanobacteria and accumulation of cyanotoxins. To shed light on this previously unexplored research area in desert environments, we examined drinking and irrigation water of urban and rural environments to determine whether cyanobacteria and cyanotoxins are present, and what are the storage and transportation practices as well as the environmental parameters that best predict their presence. Cyanobacteria were present in 80% of the urban and 33% of the rural water impoundments. Neurotoxins BMAA, DAB and anatoxin-a(S) were not detected in any of the water samples, although they have been found to accumulate in the desert soils, which suggests a bioaccumulation potential if they are leached into the aquifer. A toxic BMAA isomer, AEG, was found in 91.7% of rural but none of the urban water samples and correlated with water-truck transportation, light exposure and chloride ions. The hepatotoxic cyanotoxin microcystin-LR was present in the majority of all sampled impoundments, surpassing the WHO provisional guideline of 1 μg/l in 30% of the urban water tanks. Finally, we discuss possible management strategies to improve storage and transportation practices in order to minimize exposure to cyanobacteria and cyanotoxins, and actions to promote sustainable use of limited water resources.

  18. Environmental Transmission Electron Microscopy in an Aberration-Corrected Environment

    DEFF Research Database (Denmark)

    Hansen, Thomas W.; Wagner, Jakob B.

    2012-01-01

    The increasing use of environmental transmission electron microscopy (ETEM) in materials science provides exciting new possibilities for investigating chemical reactions and understanding both the interaction of fast electrons with gas molecules and the effect of the presence of gas on high-resol...

  19. Preparation and Characterization of the Activated Carbon-Nylon Beads: Novel Material for In Situ Microbe Sampler and Microcosm Experiment in Groundwater Environment

    Science.gov (United States)

    Liu, J.; Liu, H.

    2015-12-01

    The organic pollution of groundwater is a widespread problem in the word. It is significant to study the microbial community especially related to organic contaminant biodegradation and their variation with groundwater environment parameters, so as to evaluate the biodegradability of the organic contaminants and then make a right decision for bioremediation. One of good ways for this study is to build a microcosm in groundwater containing target contaminant, where microbes especially relating to biodegradation will grow in the microcosm and be collected for analysis. This research aims to prepare a novel material for in situ microbe sampler and microcosm experiment in groundwater environment. The novel material, namely, the activated carbon-nylon (AC-N) beads, was prepared using activated carbon and nylon as main raw materials. The material consists of 3-4mm diameter spherical beads (Fig.1A and Fig.2 A) which have an internal surface area greater than 500 m2 g-1. FT-IR spectra (Fig.3) indicated the composition of activated carbon and nylon due to the variation of the peaks at the near 1627 cm-1and 1558 -1538 cm-1 before and after complex reaction. The equilibrium adsorption capacity of benzene on the beads was 16.76 mg/g at the initial concentration of 100 mg/L. The adsorption kinetics was found to follow the pseudo-second-order kinetic model (Fig.4). The mechanism of the adsorption process was determined from the intraparticle diffusion model. Camera and SEM images (Fig.1 B and Fig.2 A and B) showed that the beads had an open and channel pore structures, the microbes might enter into and grow up in the beads (Fig.1 C and Fig.2 C). All these results showed that the AC-N beads could form the in situ microcosm of organic pollutants and microbes, which provided a promising prospect for assessing the biodegradability of the organic pollutants by intrinsic microbes in the groundwater.

  20. Quantitative assessment of possible human health risk associated with consumption of arsenic contaminated groundwater and wheat grains from Ropar Wetand and its environs.

    Science.gov (United States)

    Sharma, Sakshi; Kaur, Jagdeep; Nagpal, Avinash Kaur; Kaur, Inderpreet

    2016-09-01

    Arsenic (As) is a carcinogenic metalloid that enters food chain through food and water and poses health risk to living beings. It is important to assess the As status in the environment and risks associated with it. Hence, a risk assessment study was conducted across Ropar wetland, Punjab, India and its environs in pre-monsoon season of 2013, to estimate the risk posed to adults and children via daily consumption of As contaminated groundwater and wheat grains. Arsenic concentrations determined in groundwater, soil and wheat grain samples using atomic absorption spectrometer ranged from 2.90 to 10.56 μg L(-1), 0.06 to 0.12 mg kg(-1) and 0.03 to 0.21 mg kg(-1), respectively. Arsenic in wheat grains showed significant negative correlation with phosphate content in soil indicating a competitive uptake of arsenate and phosphate ions by plants. Principal component analysis and cluster analysis suggested that both natural and anthropogenic factors contribute to variation in As content and other variables studied in soil and groundwater samples. Total cancer risk and hazard index were higher than the USEPA safety limits of 1.00 × 10(-6) and 1, respectively, for both adults and children indicating a high risk of cancer and other health disorders. Consumption of As contaminated wheat grains was found to pose higher risk of cancer and non-cancer health disorders as compared to intake of As contaminated groundwater by both adults and children. Moreover, children were found to be more prone to cancer and other heath disorders due to As exposure via wheat grains and groundwater as compared to adults.

  1. Groundwater Recharge Rates and Surface Runoff Response to Land Use and Land Cover Changes in Semi-arid Environments

    Science.gov (United States)

    Owuor, Steven; Butterbach-Bahl, Klaus; Guzha, Alphonce; Rufino, Mariana; Pelster, David; Díaz-Pinés, Eugenio; Breuer, Lutz; Merbold, Lutz

    2017-04-01

    Conclusive evidence and understanding of the effects of land use and land cover (LULC) on both groundwater recharge and surface runoff is critical for effective management of water resources in semi-arid region as those heavily depend on groundwater resources. However, there is limited quantitative evidence on how changes to LULC in semi-arid tropical and subtropical regions affect the subsurface components of the hydrologic cycle, particularly groundwater recharge. In this study, we reviewed a total of 27 studies (2 modelling and 25 experimental), which reported on pre- and post-land use change groundwater recharge or surface runoff magnitude, and thus allowed to quantify the response of groundwater recharge rates and runoff to LULC. Restoration of bare land induces a decrease in groundwater recharge from 42 % of precipitation to between 6 and 12 % depending on the final LULC. If forests are cleared for rangelands, groundwater recharge increases by 7.8 ± 12.6 %, while conversion to cropland or grassland results in increases of 3.4 ± 2.5 and 4.4 ± 3.3 %, respectively. Rehabilitation of bare land to cropland results in surface runoff reductions of between 5.2 and 7.3 %. The conversion of forest vegetation to managed LULC shows an increase in surface runoff from 1 to 14.1 % depending on the final LULC. Surface runoff is reduced from 2.5 to 1.1 % when grassland is converted to forest vegetation. While there is general consistency in the results from the selected case studies, we conclude that there are few experimental studies that have been conducted in tropical and subtropical semi-arid regions, despite that many people rely heavily on groundwater for their livelihoods. Therefore, there is an urgent need to increase the body of quantitative evidence given the pressure of growing human population and climate change on water resources in the region.

  2. Sulfate Reduction in Groundwater: Characterization and Applications for Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Z.; Brusseau, M. L.; Carroll, Kenneth C.; Carreon-Diazconti, C.; Johnson, B.

    2012-06-01

    Sulfate is ubiquitous in groundwater, with both natural and anthropogenic sources. Sulfate reduction reactions play a significant role in mediating redox conditions and biogeochemical processes for subsurface systems. They also serve as the basis for innovative in-situ methods for groundwater remediation. An overview of sulfate reduction in subsurface environments is provided, with a specific focus on implications for groundwater remediation. A case study presenting the results of a pilot-scale ethanol injection test illustrates the advantages and difficulties associated with the use of electron-donor amendments for sulfate remediation.

  3. Re-configurable electronics behavoir under extreme thermal environment

    Science.gov (United States)

    Stoica, Adrian; Lacayo, Veronica; Rajeshuni, Ramesham; Keymeulen, Didier; Zebulum, Ricardo; Neff, Joe; Burke, Gary; Daud, Taher

    2005-01-01

    This paper focuses on analog/digital electronics at low-temperatures. The experiments cover separate tests of the whole Evolvable Hardware system: the Evolutionary Processor (the DSP in the SABLE system), Xilinx Virtes II Pro FPGA evaluation board, and the Reconfigurable analog array components tested at low and high temperatures.

  4. Teaching Teamwork: Electronics Instruction in a Collaborative Environment

    Science.gov (United States)

    Horwitz, Paul; von Davier, Alina; Chamberlain, John; Koon, Al; Andrews, Jessica; McIntyre, Cynthia

    2017-01-01

    The Teaching Teamwork Project is using an online simulated electronic circuit, running on multiple computers, to assess students' abilities to work together as a team. We pose problems that must be tackled collaboratively, and log students' actions as they attempt to solve them. Team members are isolated from one another and can communicate only…

  5. Exploring the Academic Self within an Electronic Mail Environment.

    Science.gov (United States)

    Spires, Hiller A.; Mason, Cheryl; Crissman, Cris; Jackson, Alecia

    2001-01-01

    Reports on a study at North Carolina State University that examined the use of electronic mail to encourage critical literacy among college developmental reading students. States that randomly selected students were paired with professionals who served as online mentors. Reports that, after one semester, this group scored higher than the control…

  6. Groundwater recharge in a semi-arid environment under high climatic variability and over-pumping: Ajlun Highlands example, Jordan.

    Science.gov (United States)

    Raggad, Marwan; Salameh, Elias; Magri, Fabien; Siebert, Christian; Roediger, Tino; Moller, Peter

    2016-04-01

    Jordan's ground water resources are being exploited up to 190% of the safe yield while rainfall rates are decreasing and highly variable, thereby affecting recharge volumes of the aquifers. The Ajlun highlands, forming the northwestern edge of Jordan are characterized by annual rainfall rates exceeding 500 mm, the highest in the country, which leads to accordingly high replenishment of almost the entire groundwater system in northern Jordan. The high recharge and the NW-wards dipping strata lead to a groundwater flow towards the north and northwest, areas which host the vital aquifers of the region. Limited and degraded groundwater recharge combined with growing over-pumping are the main issues that regard the northern groundwater basins, such as Wadi Arab, Yarmouk and the Jordan Valley side basins. To evaluate the groundwater potential under high recharge variability, groundwater recharge was modeled and compared to different Global Circulation Models (GCMs). Groundwater recharge was calculated based on climatic data covering the time period from 1965 to 2014. Recharge modeling was conducted by applying the J2000 water budget model. The simulation of hydrologic processes uses independent parameters that are calculated prior to simulate the recharge flow. The simulations estimate recharge of 47.6 MCM, which is 12% less than the values given by the Jordanian authorities. The low calculated recharge is likely due to an overestimation of the evapotranspiration in areas with high topographic slopes. To examine the variability of groundwater recharge under current climatic conditions, statistical downscaling of global circulation models was conducted for the time period 1965 - 2000. Data for the time period 2001 - 2014 was used for the model validation. Results indicated a decline of 18.7% in precipitation by the year 2050 with an increase of 1.7 and 2.2 degrees in maximum and minimum temperatures respectively. Accordingly recharge for the year 2050 is 27% less than

  7. Flexible Electronics-Based Transformers for Extreme Environments

    Science.gov (United States)

    Quadrelli, Marco B.; Stoica, Adrian; Ingham, Michel; Thakur, Anubhav

    2015-01-01

    This paper provides a survey of the use of modular multifunctional systems, called Flexible Transformers, to facilitate the exploration of extreme and previously inaccessible environments. A novel dynamics and control model of a modular algorithm for assembly, folding, and unfolding of these innovative structural systems is also described, together with the control model and the simulation results.

  8. Monitoring and Management of Karstic Coastal Groundwater in a Changing Environment (Southern Italy: A Review of a Regional Experience

    Directory of Open Access Journals (Sweden)

    Maurizio Polemio

    2016-04-01

    Full Text Available The population concentration in coastal areas and the increase of groundwater discharge in combination with the peculiarities of karstic coastal aquifers constitute a huge worldwide problem, which is particularly relevant for coastal aquifers of the Mediterranean basin. This paper offers a review of scientific activities realized to pursue the optimal utilization of Apulian coastal groundwater. Apulia, with a coastline extending for over 800 km, is the Italian region with the largest coastal karst aquifers. Apulian aquifers have suffered both in terms of water quality and quantity. Some regional regulations were implemented from the 1970s with the purpose of controlling the number of wells, well locations, and well discharge. The practical effects of these management criteria, the temporal and spatial trend of recharge, groundwater quality, and seawater intrusion effects are discussed based on long-term monitoring. The efficacy of existing management tools and the development of predictive scenarios to identify the best way to reconcile irrigation and demands for high-quality drinking water have been pursued in a selected area. The Salento peninsula was selected as the Apulian aquifer portion exposed to the highest risk of quality degradation due to seawater intrusion. The capability of large-scale numerical models in groundwater management was tested, particularly for achieving forecast scenarios to evaluate the impacts of climate change on groundwater resources. The results show qualitative and quantitative groundwater trends from 1930 to 2060 and emphasize the substantial decrease of the piezometric level and a serious worsening of groundwater salinization due to seawater intrusion.

  9. Smart Electronic Laboratory Notebooks for the NIST Research Environment.

    Science.gov (United States)

    Gates, Richard S; McLean, Mark J; Osborn, William A

    2015-01-01

    Laboratory notebooks have been a staple of scientific research for centuries for organizing and documenting ideas and experiments. Modern laboratories are increasingly reliant on electronic data collection and analysis, so it seems inevitable that the digital revolution should come to the ordinary laboratory notebook. The most important aspect of this transition is to make the shift as comfortable and intuitive as possible, so that the creative process that is the hallmark of scientific investigation and engineering achievement is maintained, and ideally enhanced. The smart electronic laboratory notebooks described in this paper represent a paradigm shift from the old pen and paper style notebooks and provide a host of powerful operational and documentation capabilities in an intuitive format that is available anywhere at any time.

  10. Electronic Waste: A Growing Concern in Today's Environment

    Directory of Open Access Journals (Sweden)

    M. Khurrum S. Bhutta

    2011-01-01

    Full Text Available Over the recent past, the global market of electrical and electronic equipment (EEE has grown exponentially, while the lifespan of these products has become increasingly shorter. More of these products are ending up in rubbish dumps and recycling centers, posing a new challenge to policy makers. The purpose of this paper is to provide a review of the e-Waste problem and to put forward an estimation technique to calculate the growth of e-Waste.

  11. Secure dissemination of electronic healthcare records in distributed wireless environments.

    Science.gov (United States)

    Belsis, Petros; Vassis, Dimitris; Skourlas, Christos; Pantziou, Grammati

    2008-01-01

    A new networking paradigm has emerged with the appearance of wireless computing. Among else ad-hoc networks, mobile and ubiquitous environments can boost the performance of systems in which they get applied. Among else, medical environments are a convenient example of their applicability. With the utilisation of wireless infrastructures, medical data may be accessible to healthcare practitioners, enabling continuous access to medical data. Due to the critical nature of medical information, the design and implementation of these infrastructures demands special treatment in order to meet specific requirements; among else, special care should be taken in order to manage interoperability, security, and in order to deal with bandwidth and hardware resource constraints that characterize the wireless topology. In this paper we present an architecture that attempts to deal with these issues; moreover, in order to prove the validity of our approach we have also evaluated the performance of our platform through simulation in different operating scenarios.

  12. Developing a Records Management Programme in the Electronic Environment

    CERN Document Server

    Hare, Catherine

    2012-01-01

    A practical approach to developing and operating an effective programme to manage hybrid records within an organization. This title positions records management as an integral business function linked to the organization's business aims and objectives. The authors also address the records requirements of new and significant pieces of legislation, such as data protection and freedom of information, as well as exploring strategies for managing electronic records. Bullet points, checklists and examples assist the reader throughout, making this a one-stop resource for information in this area.

  13. A model for hypermedia learning environments based on electronic books

    Directory of Open Access Journals (Sweden)

    Ignacio Aedo

    1997-12-01

    Full Text Available Current hypermedia learning environments do not have a common development basis. Their designers have often used ad-hoc solutions to solve the learning problems they have encountered. However, hypermedia technology can take advantage of employing a theoretical scheme - a model - which takes into account various kinds of learning activities, and solves some of the problems associated with its use in the learning process. The model can provide designers with the tools for creating a hypermedia learning system, by allowing the elements and functions involved in the definition of a specific application to be formally represented.

  14. Design and Testing of Electronic Devices for Harsh Environments

    CERN Document Server

    Nico, Costantino

    This thesis reports an overview and the main results of the research activity carried out within the PhD programme in Information Engineering of the University of Pisa (2010-2012). The research activity has been focused on different fields, including Automotive and High Energy Physics experiments, according to a common denominator: the development of electroni c devices and systems operating in harsh environments. There are many applications that forc e the adoption of design methodologies and strategies focused on this type of envir onments: military, biom edical, automotive, industrial and space. The development of solutions fulfilling specific operational requirements, therefore represents an interesting field of research. The first research activity has been framed within the ATHENIS project, funded by the CORDIS Commission of the European Community, and aiming at the development of a System-on-Chip, a r egulator for alternators employed on vehicles, presenting both configurability an d t...

  15. Quality Detection of Litchi Stored in Different Environments Using an Electronic Nose

    Directory of Open Access Journals (Sweden)

    Sai Xu

    2016-06-01

    Full Text Available The purpose of this paper was to explore the utility of an electronic nose to detect the quality of litchi fruit stored in different environments. In this study, a PEN3 electronic nose was adopted to test the storage time and hardness of litchi that were stored in three different types of environment (room temperature, refrigerator and controlled-atmosphere. After acquiring data about the hardness of the sample and from the electronic nose, linear discriminant analysis (LDA, canonical correlation analysis (CCA, BP neural network (BPNN and BP neural network-partial least squares regression (BPNN-PLSR, were employed for data processing. The experimental results showed that the hardness of litchi fruits stored in all three environments decreased during storage. The litchi stored at room temperature had the fastest rate of decrease in hardness, followed by those stored in a refrigerator environment and under a controlled-atmosphere. LDA has a poor ability to classify the storage time of the three environments in which litchi was stored. BPNN can effectively recognize the storage time of litchi stored in a refrigerator and a controlled-atmosphere environment. However, the BPNN classification of the effect of room temperature storage on litchi was poor. CCA results show a significant correlation between electronic nose data and hardness data under the room temperature, and the correlation is more obvious for those under the refrigerator environment and controlled-atmosphere environment. The BPNN-PLSR can effectively predict the hardness of litchi under refrigerator storage conditions and a controlled-atmosphere environment. However, the BPNN-PLSR prediction of the effect of room temperature storage on litchi and global environment storage on litchi were poor. Thus, this experiment proved that an electronic nose can detect the quality of litchi under refrigeratored storage and a controlled-atmosphere environment. These results provide a useful

  16. Quality Detection of Litchi Stored in Different Environments Using an Electronic Nose

    Science.gov (United States)

    Xu, Sai; Lü, Enli; Lu, Huazhong; Zhou, Zhiyan; Wang, Yu; Yang, Jing; Wang, Yajuan

    2016-01-01

    The purpose of this paper was to explore the utility of an electronic nose to detect the quality of litchi fruit stored in different environments. In this study, a PEN3 electronic nose was adopted to test the storage time and hardness of litchi that were stored in three different types of environment (room temperature, refrigerator and controlled-atmosphere). After acquiring data about the hardness of the sample and from the electronic nose, linear discriminant analysis (LDA), canonical correlation analysis (CCA), BP neural network (BPNN) and BP neural network-partial least squares regression (BPNN-PLSR), were employed for data processing. The experimental results showed that the hardness of litchi fruits stored in all three environments decreased during storage. The litchi stored at room temperature had the fastest rate of decrease in hardness, followed by those stored in a refrigerator environment and under a controlled-atmosphere. LDA has a poor ability to classify the storage time of the three environments in which litchi was stored. BPNN can effectively recognize the storage time of litchi stored in a refrigerator and a controlled-atmosphere environment. However, the BPNN classification of the effect of room temperature storage on litchi was poor. CCA results show a significant correlation between electronic nose data and hardness data under the room temperature, and the correlation is more obvious for those under the refrigerator environment and controlled-atmosphere environment. The BPNN-PLSR can effectively predict the hardness of litchi under refrigerator storage conditions and a controlled-atmosphere environment. However, the BPNN-PLSR prediction of the effect of room temperature storage on litchi and global environment storage on litchi were poor. Thus, this experiment proved that an electronic nose can detect the quality of litchi under refrigeratored storage and a controlled-atmosphere environment. These results provide a useful reference for future

  17. Adaptations in Electronic Structure Calculations in Heterogeneous Environments

    Energy Technology Data Exchange (ETDEWEB)

    Talamudupula, Sai [Iowa State Univ., Ames, IA (United States)

    2011-01-01

    Modern quantum chemistry deals with electronic structure calculations of unprecedented complexity and accuracy. They demand full power of high-performance computing and must be in tune with the given architecture for superior e ciency. To make such applications resourceaware, it is desirable to enable their static and dynamic adaptations using some external software (middleware), which may monitor both system availability and application needs, rather than mix science with system-related calls inside the application. The present work investigates scienti c application interlinking with middleware based on the example of the computational chemistry package GAMESS and middleware NICAN. The existing synchronous model is limited by the possible delays due to the middleware processing time under the sustainable runtime system conditions. Proposed asynchronous and hybrid models aim at overcoming this limitation. When linked with NICAN, the fragment molecular orbital (FMO) method is capable of adapting statically and dynamically its fragment scheduling policy based on the computing platform conditions. Signi cant execution time and throughput gains have been obtained due to such static adaptations when the compute nodes have very di erent core counts. Dynamic adaptations are based on the main memory availability at run time. NICAN prompts FMO to postpone scheduling certain fragments, if there is not enough memory for their immediate execution. Hence, FMO may be able to complete the calculations whereas without such adaptations it aborts.

  18. Parrot Interpreter: Representation, Extinction and the Electronic Information Environment

    Directory of Open Access Journals (Sweden)

    Paul Carter

    2013-08-01

    Full Text Available Humans, it seems, can’t get enough of parrots. Ethnography, folklore, psychology, and, of course, imaginative literature all offer copious evidence of our fantasy of living with, communicating with and even being parrots. The natural history of parrots and the cultural history of parrots present something of a conundrum: on the one hand, a massive destructiveness (illegal bird and feather trade, environment destruction, scientific collections; on the other, an often erotically inflected sympathetic identification leading to the production of new forms. It’s strange to realise that Europe is infested with a shadow population of captive and inbred budgerigars, whose numbers far exceed those remaining in the wild and who can never return to their origins. If, as our privileged other, our uncanny mimic and double, the parrot still fails to survive, what does this tell us about our economy of desire? It seems that to know is to consume and destroy; and that the apparent contrast between the operations of the rainforest loggers and bird-trappers and the sentimental representations and transformations parrot suffers in human society is overdrawn. How is this contradiction to be explained?

  19. Development of a Conductivity Sensor for Monitoring Groundwater Resources to Optimize Water Management in Smart City Environments.

    Science.gov (United States)

    Parra, Lorena; Sendra, Sandra; Lloret, Jaime; Bosch, Ignacio

    2015-08-26

    The main aim of smart cities is to achieve the sustainable use of resources. In order to make the correct use of resources, an accurate monitoring and management is needed. In some places, like underground aquifers, access for monitoring can be difficult, therefore the use of sensors can be a good solution. Groundwater is very important as a water resource. Just in the USA, aquifers represent the water source for 50% of the population. However, aquifers are endangered due to the contamination. One of the most important parameters to monitor in groundwater is the salinity, as high salinity levels indicate groundwater salinization. In this paper, we present a specific sensor for monitoring groundwater salinization. The sensor is able to measure the electric conductivity of water, which is directly related to the water salinization. The sensor, which is composed of two copper coils, measures the magnetic field alterations due to the presence of electric charges in the water. Different salinities of the water generate different alterations. Our sensor has undergone several tests in order to obtain a conductivity sensor with enough accuracy. First, several prototypes are tested and are compared with the purpose of choosing the best combination of coils. After the best prototype was selected, it was calibrated using up to 30 different samples. Our conductivity sensor presents an operational range from 0.585 mS/cm to 73.8 mS/cm, which is wide enough to cover the typical range of water salinities. With this work, we have demonstrated that it is feasible to measure water conductivity using solenoid coils and that this is a low cost application for groundwater monitoring.

  20. Effect of cluster environment on the electron attachment to 2-nitrophenol*

    Science.gov (United States)

    Kočišek, Jaroslav; Grygoryeva, Kateryna; Lengyel, Jozef; Fárník, Michal; Fedor, Juraj

    2016-04-01

    Effect of cluster environment on the electron attachment to 2-nitrophenol (2NP) is studied in homogeneous 2NP clusters and heterogeneous clusters of 2NP, argon and water. The cluster environment significantly reduces fragmentation of 2NP after electron attachment. Parent cluster anions 2NPn- are primary reaction products in both, homogeneous and heterogeneous clusters. Non-dissociative electron attachment to homogeneous clusters proceeds at low energies web page at http://dx.doi.org/10.1140/epjd/e2016-70074-0

  1. Spacecraft Environments Interactive: Space Radiation and Its Effects on Electronic System

    Science.gov (United States)

    Howard, J. W., Jr.; Hardage, D. M.

    1999-01-01

    The natural space environment is characterized by complex and subtle phenomena hostile to spacecraft. Effects of these phenomena impact spacecraft design, development, and operation. Space systems become increasingly susceptible to the space environment as use of composite materials and smaller, faster electronics increases. This trend makes an understanding of space radiation and its effects on electronic systems essential to accomplish overall mission objectives, especially in the current climate of smaller/better/cheaper faster. This primer outlines the radiation environments encountered in space, discusses regions and types of radiation, applies the information to effects that these environments have on electronic systems, addresses design guidelines and system reliability, and stresses the importance of early involvement of radiation specialists in mission planning, system design, and design review (part-by-part verification).

  2. Groundwater resources of the aquifers of the northern Central African Republic (Ouham Province). First hydrogeological investigations in a changing environment.

    Science.gov (United States)

    Djebebe-Ndjiguim, Chantal; Foto, Eric; Backo, Salé; Nguerekossi, Bruno; Zoudamba, Narcisse; Basse-Keke, Eric; Allahdin, Oscar; Huneau, Frédéric; Garel, Emilie; Celle-Jeanton, Hélène; Mabingui, Joseph

    2017-04-01

    Groundwater is a key factor in the socio-economic development of African societies. This is particularly true for the Lake Chad Basin countries for which groundwater is the main water resource for both drinking water supply for population and agriculture, whether small or large scale. The Central African Republic (CAR) occupies a strategic place in the Lake Chad Basin since most waters feeding the different tributaries of the Chari River, which is the main water source of the Lake Chad, are originating from its territory. Indeed, the Northern CAR and particularly the Ouham Province, at the head of the whole Chad endoreic watershed, benefits from favourable rainfall conditions. Unfortunately, very little hydrological and hydrogeological information is available for this area which has never been investigated in terms of geochemical and isotope characterisation. The only available spares technical and scientific investigations over the area are dating from the 1960's. Unfortunately the Lake Chad basin has undergone strong climatological evolutions since the 1970's and hydrological information needs to be updated. The objectives of this study are to characterise groundwater from the Ouham Province in order to better appreciate the hydrogeological processes taking place in the recharge area of the Southern Lake Chad Basin. Isotope hydrology combined with geochemistry of groundwater has now proven being the best approach in under-documented territories to have a first diagnostic on the dynamics and quality of available resources. In this purpose combined hydrogeochemical and isotopic investigations (18O, 2H and 3H of the water molecule) have been launched to constrain groundwater origin, recharge processes, quality, residence time and anthropogenic fingerprint on aquifers. After two sampling campaigns it was possible to draw a general pattern of the hydrogeological and hydrochemical conditions in the region. The Ouham province is mostly composed of Precambrian

  3. A Combined Hydrological, Geochemical and Geophysical Reconnaissance of Groundwater Contamination In Oilfield Environment (republic of Tatarstan, Russia)

    Science.gov (United States)

    Levitski, A.; Titov, K.; Buès, M.; Ilyin, Yu.; Konosavski, P.; Kharkhordin, I.; Uchaev, V.; Sapozhnikov, B.; Kharkovski, K.

    Numerous brine leakages from production and injection wells and pipelines were ob- served at the site of study situated in Romashkinskoye oilfield. The groundwater flow, which follows the relief, is manifested by five springs. The salinity of these springs significantly increased during 20 years of oil exploitation at the site. The subsurface consists of sandstone, clayey sandstone, siltstone and limestone. Sampling of spring water and soils, as well as geophysical investigations, were carried out to develop the groundwater and contamination flow model of the site. In addition to the traditional bulk soil sampling, the mobile forms of chemical elements were investigated using the diffusion sampling technique (Levitski et al., 1995). The dipole-dipole resistivity and Spontaneous Polarization (SP) maps of the site were obtained. One prospecting bore- hole of 40 m was sunk. Vertical Electrical Sounding (VES) and Time Domain Spec- tral Induced Polarization Sounding (SIP), conducted at several points, were inverted to obtain rock and soil resistivity. The SIP measurements were performed to help geo- logical interpretation of the obtained resistivity cross-sections. The groundwater flow model was developed on the basis of borehole data, debits of the observed springs, and surface geophysical data. The model was calibrated using numerical modelling of SP. The 2D program GWFGEM based on the SillSs approach (1983) was applied. First, the preliminary groundwater flow model was obtained. Based on the coupling flow theory, sources of SP were calculated from water heads. Then, SP was calculated on the basis of SP sources and subsurface resistivity derived from the VES inversion. The above procedure was repeated several times to minimise the discrepancy between the observed and calculated SP. The flow balance for the whole site was obtained. The best indicators of the oil-related contamination at the site were found to be: (1) in groundwater U K, Na and Sr; (2) in bulk soil U Ca

  4. Library usage patterns in the electronic information environment. Electronic journals, Use studies, Libraries, Medical libraries

    Directory of Open Access Journals (Sweden)

    B. Franklin

    2004-01-01

    Full Text Available This paper examines the methodology and results from Web-based surveys of more than 15,000 networked electronic services users in the United States between July 1998 and June 2003 at four academic health sciences libraries and two large main campus libraries serving a variety of disciplines. A statistically valid methodology for administering simultaneous Web-based and print-based surveys using the random moments sampling technique is discussed and implemented. Results from the Web-based surveys showed that at the four academic health sciences libraries, there were approximately four remote networked electronic services users for each in-house user. This ratio was even higher for faculty, staff, and research fellows at the academic health sciences libraries, where more than five remote users for each in-house user were recorded. At the two main libraries, there were approximately 1.3 remote users for each in-house user of electronic information. Sponsored research (grant funded research accounted for approximately 32% of the networked electronic services activity at the health sciences libraries and 16% at the main campus libraries. Sponsored researchers at the health sciences libraries appeared to use networked electronic services most intensively from on-campus, but not from in the library. The purpose of use for networked electronic resources by patrons within the library is different from the purpose of use of those resources by patrons using the resources remotely. The implications of these results on how librarians reach decisions about networked electronic resources and services are discussed.

  5. Electronic Journals in the Digital Environment:Issues and Future Trends

    Institute of Scientific and Technical Information of China (English)

    Jian Wang; Arthur Hendricks

    2004-01-01

    Building and managing electronic journal collections in the digital environment poses many challenges for librarians, as electronic journals exist in a complex and constantly changing state involving different digital formats, new pricing structures, and various access routes. This paper reviews critical issues that North American libraries face in managing electronic journals, including a brief history, the selection criteria, consortia purchasing, licensing, operational costs, providing access, user support, usage statistics,canceling print subscriptions, and electronic journal archives. Future trends discussed include open access e-journals, and the continuing development of e-journal collections and best practices in managing this essential constituent of academic library collections.

  6. Jiangsu Changqiang Steel Mill Groundwater Environment Impact Assessment%江苏长强钢铁厂地下水环境影响评价

    Institute of Scientific and Technical Information of China (English)

    骆祖江; 于丹丹; 刘艳; 廖翔

    2014-01-01

    为正确评价江苏长强钢铁厂拟建项目的建设运行对地下水环境的影响,在合理概化水文地质概念模型的基础上,构建了与之相应的地下水渗流和溶质运移的数值模型。通过对新建厂区运行20年的污染物运移情况进行数值模拟,确定出污染物扩散范围。结果表明,新建厂区周围地下水环境已受到污染,但影响范围及程度有限,平面上仅局限在厂区内,均未超过污染源下游100m;剖面上仅局限在潜水含水层及微承压孔隙含水层内,不涉及承压含水层。%In order to properly evaluate impacts on groundwater environment in the Changqiang Steel Mill from proposed project con-struction and operation, a corresponding groundwater seepage and solute transport numerical model has been modeled on the basis of reasonably generalized hydrogeological conceptual model. Based on the new factory area pollutant migration in 20 years has carried out numerical simulation to identify pollutant spread range. The result has shown that the groundwater environment around the new factory has been polluted, but the impact scope and degree are limited. View from the plane, polluted area is confined within factory area, no more than 100m downstream of the pollution sources;from the profile, polluted area is limited within the phreatic aquifer and slightly confined aquifer, while confined aquifer not involved.

  7. [Effects of canal-lining project on groundwater and ecological environment in Hetao Irrigation District of Inner Mongolia].

    Science.gov (United States)

    Du, Jun; Yang, Pei-Ling; Ren, Shu-Mei; Li, Yun-Kai; Wang, Yong-Zhong; Yuan, Xiao-Qi; Li, Xian-Yue; Du, Jing

    2011-01-01

    The canal-lining project in Hetao Irrigation District (HID) for water-saving irrigation has been implemented for many years. By using statistical method, ordinary Kriging, and software ArcGIS 9.0, this paper analyzed the spatiotemporal variation of groundwater table depth and salinity in HID in September, 2001 and 2009. In the meantime, the vegetation distribution on the both shores of the lining part and non-lining part of Yangjiahe channel was also investigated. After the many years implementation of the project, the water diversion amount in HID in 2009 was reduced to 44.5 x 10(8) m3. The region area of groundwater table with a depth of 2.5-3.0 m was increased from 1.2 x 10(4) hm2 in 2001 to 9.11 x 10(4) hm2 in 2009. The region area of groundwater table with a depth of 2.0-2.5 m in 2009 took 80% of the total area of HID. In the northwestern region of HID, the groundwater salinity had reduced from 5000-10000 mg x L(-1) to 3000-5000 mg x L(-1). In Wulate irrigation region, the areas of salt water belt and half-salt water belt were increasing. After the canal-lining of Yangjiahe channel, the plant species and diversity index on both shores reduced, and some herbaceous plants with shallow roots showed degradation signs. The implementation of the project and the reduction of water diversion for irrigation did not exert negative effects on the maintenance of water surface area of Wuliangsuhai Lake.

  8. Lead isotopes in soils and groundwaters as tracers of the impact of human activities on the surface environment: The Domizio-Flegreo Littoral (Italy) case study

    Science.gov (United States)

    Grezzi, G.; Ayuso, R.A.; de Vivo, B.; Lima, A.; Albanese, S.

    2011-01-01

    The isotopic signature of geogenic and anthropogenic materials, in combination with concentration data for pollutants, can help trace the origin and the extent of contamination in the environment. This approach is particularly effective if naturally occurring and anthropogenically introduced metals have different isotopic ratios. Lead isotope analysis on soils from 7 profiles (1. m depth) and on groundwaters from 8 wells have been used to determine the impact of human activities on the surface environment of Domizio-Flegreo Littoral. Result obtained show that in sub-rural areas the isotopic composition of the samples collected along the soil profiles of Domizio-Flegreo Littoral is likely mostly controlled by the nature of the parent geologic material (natural) while in more urbanized areas (Giugliano) Pb isotopic composition in superficial soils is mostly influenced by anthropic sources such as motor vehicles. Lead isotopic ratios in groundwaters also show that the use of pesticides and, probably, the influence of aerosols and the presence of illegal waste disposal can influence water quality. ?? 2010 Elsevier B.V.

  9. Subsurface aeration of anaerobic groundwater : iron colloid formation and the nitrification process

    NARCIS (Netherlands)

    Wolthoorn, A.

    2003-01-01

    Keywords: Iron, anaerobic groundwater, groundwater purification, heterogeneous oxidation, iron colloid formation, electron microscopy, nitrification In anaerobic groundwater iron and ammonium can be found in relatively high concentrations. These substances need to be removed when groundwater is used

  10. Evolution of chemical and isotopic composition of inorganic carbon in a complex semi-arid zone environment: Consequences for groundwater dating using radiocarbon

    Science.gov (United States)

    Meredith, K. T.; Han, L. F.; Hollins, S. E.; Cendón, D. I.; Jacobsen, G. E.; Baker, A.

    2016-09-01

    Estimating groundwater age is important for any groundwater resource assessment and radiocarbon (14C) dating of dissolved inorganic carbon (DIC) can provide this information. In semi-arid zone (i.e. water-limited environments), there are a multitude of reasons why 14C dating of groundwater and traditional correction models may not be directly transferable. Some include; (1) the complex hydrological responses of these systems that lead to a mixture of different ages in the aquifer(s), (2) the varied sources, origins and ages of organic matter in the unsaturated zone and (3) high evaporation rates. These all influence the evolution of DIC and are not easily accounted for in traditional correction models. In this study, we determined carbon isotope data for; DIC in water, carbonate minerals in the sediments, sediment organic matter, soil gas CO2 from the unsaturated zone, and vegetation samples. The samples were collected after an extended drought, and again after a flood event, to capture the evolution of DIC after varying hydrological regimes. A graphical method (Han et al., 2012) was applied for interpretation of the carbon geochemical and isotopic data. Simple forward mass-balance modelling was carried out on key geochemical processes involving carbon and agreed well with observed data. High values of DIC and δ13CDIC, and low 14CDIC could not be explained by a simple carbonate mineral-CO2 gas dissolution process. Instead it is suggested that during extended drought, water-sediment interaction leads to ion exchange processes within the top ∼10-20 m of the aquifer which promotes greater calcite dissolution in saline groundwater. This process was found to contribute more than half of the DIC, which is from a mostly 'dead' carbon source. DIC is also influenced by carbon exchange between DIC in water and carbonate minerals found in the top 2 m of the unsaturated zone. This process occurs because of repeated dissolution/precipitation of carbonate that is dependent on

  11. Anaerobic arsenite oxidation with an electrode serving as the sole electron acceptor: A novel approach to the bioremediation of arsenic-polluted groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Pous, Narcis [Laboratory of Chemical and Environmental Engineering (LEQUiA), Institute of the Environment, University of Girona, C/Maria Aurèlia Capmany, 69 E-17071 Girona (Spain); Casentini, Barbara; Rossetti, Simona; Fazi, Stefano [Water Research Institute (IRSA-CNR), National Research Council, Via Salaria Km 29.300, 00015 Monterotondo (Italy); Puig, Sebastià [Laboratory of Chemical and Environmental Engineering (LEQUiA), Institute of the Environment, University of Girona, C/Maria Aurèlia Capmany, 69 E-17071 Girona (Spain); Aulenta, Federico, E-mail: aulenta@irsa.cnr.it [Water Research Institute (IRSA-CNR), National Research Council, Via Salaria Km 29.300, 00015 Monterotondo (Italy)

    2015-02-11

    Highlights: • As(III) was oxidized to As(V) in a bioelectrochemical system. • A polarized graphite electrode served as electron acceptor. • Gammaproteobacteria were the dominating organisms at the electrode. - Abstract: Arsenic contamination of soil and groundwater is a serious problem worldwide. Here we show that anaerobic oxidation of As(III) to As(V), a form which is more extensively and stably adsorbed onto metal-oxides, can be achieved by using a polarized (+497 mV vs. SHE) graphite anode serving as terminal electron acceptor in the microbial metabolism. The characterization of the microbial populations at the electrode, by using in situ detection methods, revealed the predominance of gammaproteobacteria. In principle, the proposed bioelectrochemical oxidation process would make it possible to provide As(III)-oxidizing microorganisms with a virtually unlimited, low-cost and low-maintenance electron acceptor as well as with a physical support for microbial attachment.

  12. ELECTRONIC EQUIPMENT TO MONITORIZE SOME BIOLOGICAL PROCESS OF ECONOMIC IMPORTANCE IN HONEYBEE COLONY AND ITS ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    A. SICEANU

    2013-12-01

    Full Text Available The electronic hive is the result of the scientific researches carried out between2003-2006 by a research project funded by MEdC through the National ProgramRELANSIN, being accomplished by Institute for Beekeeping Research andDevelopment –Bucharest in cooperation with the Polytechnics University fromBucharest –The Center for Electronic Technology and Interconnection Techniquesand the Radio Consult CompanyTo achieve the great complexity of the electronic model adapted to the hive –the“smart” hive, it was necessary to establish the all electronic details which to makepossible to monitorize some very important information from the bee colony andits environment with the help of the honeybees and which to eliminate the errorsthat may occur in the information collection process.Thus, the project aimed to conceive the electronic system in order to collectinformation from inside the hive and from environment too, to storage andtransmit it to a data basis by GSM network in order to be analyzed and processedby users.By this complex electronic system, composed by electronic equipment and thehoney bee colony, which is dynamic and strong related with natural evolution ofvegetation correlated with the climate factors, is possible to identify instantaneousor periodically a large palette of aggression factors as well naturals (acids rains,extreme temperatures, calamities as anthropic factors –accidental chemical orbiologic pollution. The obtained data, electronically quantified and taken out intothe data basis, could offer accurate information about the moisturized areas atdifferent time intervals.

  13. Best Practices Regarding the Use of Electronic Environment for Romanian Tourism Development

    OpenAIRE

    Irina Maiorescu; Mihai Teodor Negrea; Dorin Vicențiu Popescu; Gabriel Cristian Sabou

    2016-01-01

    Information and Communication Technology (ICT) plays an important role in all sectors of activity, hence in tourism sector too. Starting from this fact, authors consider as important identifying and implementing best practices in electronic environment for sustainable development of tourism in Romania. Traditional tourism - implying at all stages specialized human support – knows profound modifications. Today, current statistics show that more and more people dive into virtual environment for...

  14. 40 CFR 265.91 - Ground-water monitoring system.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of: (1...

  15. Groundwater contamination in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Tase, Norio [Univ. of Tsukuba, Ibaraki (Japan)

    1992-07-01

    Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed. 9 refs., 3 figs., 4 tabs.

  16. Groundwater contamination in Japan

    Science.gov (United States)

    Tase, Norio

    1992-07-01

    Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed.

  17. An Evaluation of Electronic Product Design Education Using Hypermedia-Resourced Learning Environments

    Science.gov (United States)

    Page, Tom; Thorsteinsson, Gisli

    2006-01-01

    The work outlined here provides a comprehensive report and formative observations of the development and implementation of hypermedia resources for learning and teaching used in conjunction with a managed learning environment (MLE). These resources are used to enhance teaching and learning of an electronics module in product design at final year…

  18. Eavesdropping on Electronic Guidebooks: Observing Learning Resources in Shared Listening Environments.

    Science.gov (United States)

    Woodruff, Allison; Aoki, Paul M.; Grinter, Rebecca E.; Hurst, Amy; Szymanski, Margaret H.; Thornton, James D.

    This paper describes an electronic guidebook, "Sotto Voce," that enables visitors to share audio information by eavesdropping on each others guidebook activity. The first section discusses the design and implementation of the guidebook device, key aspects of its user interface, the design goals for the audio environment, the eavesdropping…

  19. An Electronic Library-Based Learning Environment for Supporting Web-Based Problem-Solving Activities

    Science.gov (United States)

    Tsai, Pei-Shan; Hwang, Gwo-Jen; Tsai, Chin-Chung; Hung, Chun-Ming; Huang, Iwen

    2012-01-01

    This study aims to develop an electronic library-based learning environment to support teachers in developing web-based problem-solving activities and analyzing the online problem-solving behaviors of students. Two experiments were performed in this study. In study 1, an experiment on 103 elementary and high school teachers (the learning activity…

  20. Ab-initio calculations on two-electron ions in strongly coupled plasma environment

    CERN Document Server

    Bhattacharyya, S; Mukherjee, T K

    2015-01-01

    In this work, the controversy between the interpretations of recent measurements on dense aluminum plasma created with Linac coherent light sources (LCLS) X-ray free electron laser (FEL) and Orion laser has been addressed. In both kind of experiments, helium-like and hydrogen-like spectral lines are used for plasma diagnostics . However, there exist no precise theoretical calculations for He-like ions within dense plasma environment. The strong need for an accurate theoretical estimates for spectral properties of He-like ions in strongly coupled plasma environment leads us to perform ab initio calculations in the framework of Rayleigh-Ritz variation principle in Hylleraas coordinates where ion-sphere potential is used. An approach to resolve the long-drawn problem of numerical instability for evaluating two-electron integrals with extended basis inside a finite domain is presented here. The present values of electron densities corresponding to disappearance of different spectral lines obtained within the fram...

  1. Library use and information-seeking behavior of veterinary medical students revisited in the electronic environment.

    Science.gov (United States)

    Pelzer, N L; Wiese, W H; Leysen, J M

    1998-07-01

    Veterinary medical students at Iowa State University were surveyed in January of 1997 to determine their general use of the Veterinary Medical Library and how they sought information in an electronic environment. Comparisons were made between this study and one conducted a decade ago to determine the effect of the growth in electronic resources on student library use and information-seeking behavior. The basic patterns of student activities in the library, resources used to find current information, and resources anticipated for future education needs remained unchanged. The 1997 students used the library most frequently for photocopying, office supplies, and studying coursework; they preferred textbooks and handouts as sources of current information. However, when these students went beyond textbooks and handouts to seek current information, a major shift was seen from the use of print indexes and abstracts in 1987 towards the use of computerized indexes and other electronic resources in 1997. Almost 60% of the students reported using the Internet for locating current information. Overall use of electronic materials was highest among a group of students receiving the problem-based learning method of instruction. Most of the students surveyed in 1997 indicated that electronic resources would have some degree of importance to them for future education needs. The electronic environment has provided new opportunities for information professionals to help prepare future veterinarians, some of whom will be practicing in remote geographical locations, to access the wealth of information and services available on the Internet and Web.

  2. Geochemical controls of groundwaters upwelling in saline environments: Case study the discharge playa of Sidi El Hani (Sahel, Tunisia)

    Science.gov (United States)

    Tagorti, Mohamed Ali; Essefi, Elhoucine; Touir, Jamel; Guellala, Rihab; Yaich, Chokri

    2013-10-01

    Within the discharge playa of Sidi El Hani, the surrounding aquifers converge due to uprising underground waters. The Principal Component Analysis proves that the fluid density is inversely influenced by the rainfall and has a reciprocal effect with evaporation. This parameter is governed by uprising groundwaters and the convergence of waters and inflow in the sabkha result in a geochemical exceptionality. The fluid density maintains high values during the year, the modeling of which shows a third sinusoidal distribution. This model remains stable along a span of time because the surrounding aquifer feeds the discharge playa by a continuous salty water flow. In general, waters in the majority of drills surrounding the discharge playa have the same facies which is mainly made up of water charged with Na+ and Cl-. A sample from the northeast of discharge playa shows a geochemical similarity with two wells located in its vicinity.

  3. Use of groundwater lifetime expectancy for the performance assessment of a deep geologic radioactive waste repository:2. Application to a Canadian Shield environment

    CERN Document Server

    Park, Y -J; Normani, S D; Sykes, J F; Sudicky, E A

    2011-01-01

    Cornaton et al. [2007] introduced the concept of lifetime expectancy as a performance measure of the safety of subsurface repositories, based upon the travel time for contaminants released at a certain point in the subsurface to reach the biosphere or compliance area. The methodologies are applied to a hypothetical but realistic Canadian Shield crystalline rock environment, which is considered to be one of the most geologically stable areas on Earth. In an approximately 10\\times10\\times1.5 km3 hypothetical study area, up to 1000 major and intermediate fracture zones are generated from surface lineament analyses and subsurface surveys. In the study area, mean and probability density of lifetime expectancy are analyzed with realistic geologic and hydrologic shield settings in order to demonstrate the applicability of the theory and the numerical model for optimally locating a deep subsurface repository for the safe storage of spent nuclear fuel. The results demonstrate that, in general, groundwater lifetime exp...

  4. Probing 67P/Churyumov-Gerasimenko's Electron Environment Through Ultraviolet Emission by Rosetta Alice Observations

    Science.gov (United States)

    Schindhelm, Eric; Noonan, John; Keeney, Brian A.; Broiles, Thomas; Bieler, Andre; A'Hearn, Michael F.; Bertaux, Jean-Loup; Feaga, Lori M.; Feldman, Paul D.; Parker, Joel Wm.; Steffl, Andrew Joseph; Stern, S. Alan; Weaver, Harold A.

    2016-10-01

    The Alice Far-Ultraviolet (FUV) Spectrograph onboard ESA's Rosetta spacecraft has observed the coma of comet 67P/Churyumov-Gerasimenko from far approach in summer 2014 until the end of mission in September 2016. We present an overall perspective of the bright FUV emission lines (HI 1026 Å, OI 1302/1305/1306 Å multiplet, OI] 1356 Å, CO 1510 (1-0) Å, and CI 1657 Å) above the sunward hemisphere, detailing their spatial extent and brightness as a function of time and the heliocentric distance of the comet. We compare our observed gas column densities derived using electron temperatures and densities from the Ion Electron Sensor (IES) with those derived using the Inner Coma Environment Simulator (ICES) models in periods when electron-impact excited emission dominates over solar fluorescence emission. The electron population is characterized with 2 three-dimensional kappa functions, one dense and warm, one rarefied and hot.

  5. Electronic Structure Calculations and Adaptation Scheme in Multi-core Computing Environments

    Energy Technology Data Exchange (ETDEWEB)

    Seshagiri, Lakshminarasimhan; Sosonkina, Masha; Zhang, Zhao

    2009-05-20

    Multi-core processing environments have become the norm in the generic computing environment and are being considered for adding an extra dimension to the execution of any application. The T2 Niagara processor is a very unique environment where it consists of eight cores having a capability of running eight threads simultaneously in each of the cores. Applications like General Atomic and Molecular Electronic Structure (GAMESS), used for ab-initio molecular quantum chemistry calculations, can be good indicators of the performance of such machines and would be a guideline for both hardware designers and application programmers. In this paper we try to benchmark the GAMESS performance on a T2 Niagara processor for a couple of molecules. We also show the suitability of using a middleware based adaptation algorithm on GAMESS on such a multi-core environment.

  6. In-Situ Measurements of the Secondary Electron Yield in an Accelerator Environment: Instrumentation and Methods

    CERN Document Server

    Hartung, W H; Conway, J V; Dennett, C A; Greenwald, S; Kim, J -S; Li, Y; Moore, T P; Omanovic, V; Palmer, M A; Strohman, C R

    2014-01-01

    The performance of a particle accelerator can be limited by the build-up of an electron cloud (EC) in the vacuum chamber. Secondary electron emission from the chamber walls can contribute to EC growth. An apparatus for in-situ measurements of the secondary electron yield (SEY) in the Cornell Electron Storage Ring (CESR) was developed in connection with EC studies for the CESR Test Accelerator program. The CESR in-situ system, in operation since 2010, allows for SEY measurements as a function of incident electron energy and angle on samples that are exposed to the accelerator environment, typically 5.3 GeV counter-rotating beams of electrons and positrons. The system was designed for periodic measurements to observe beam conditioning of the SEY with discrimination between exposure to direct photons from synchrotron radiation versus scattered photons and cloud electrons. The samples can be exchanged without venting the CESR vacuum chamber. Measurements have been done on metal surfaces and EC-mitigation coatings...

  7. Average and worst-case specifications of precipitating auroral electron environment

    Science.gov (United States)

    Hardy, D. A.; Burke, W. J.; Gussenhoven, M. S.; Holeman, E.; Yeh, H. C.

    1985-01-01

    The precipitation electrons in the auroral environment are highly variable in their energy and intensity in both space and time. As such they are a source of potential hazard to the operation of the Space Shuttle and other large spacecraft operating in polar orbit. In order to assess these hazards both the average and extreme states of the precipitating electrons must be determined. Work aimed at such a specification is presented. First results of a global study of the average characteristics are presented. In this study the high latitude region was divided into spatial elements in magnetic local time and corrected geomagnetic latitude. The average electron spectrum was then determined in each spatial element for seven different levels of activity as measured by K sub p using an extremely large data set of auroral observations. Second a case study of an extreme auroral electron environment is presented, in which the electrons are accelerated through field aligned potential as high as 30,000 volts and in which the spacecraft is seen to charge negatively to a potential approaching .5 kilovolts.

  8. The Skyrme-TQRPA calculations of electron capture on hot nuclei in pre-supernova environment

    CERN Document Server

    Dzhioev, Alan A; Stoyanov, Ch

    2016-01-01

    We combine the thermal QRPA approach with the Skyrme energy density functional theory (Skyrme-TQRPA) for modelling the process of electron capture on nuclei in supernova environment. For a sample nucleus, $^{56}$Fe, the Skyrme-TQRPA approach is applied to analyze thermal effects on the strength function of GT$_+$ transitions which dominate electron capture at $E_e\\le 30$~MeV. Several Skyrme interactions are used in order to verify the sensitivity of the obtained results to the Skyrme force parameters. Finite-temperature cross sections are calculated and the results are compared with those of the other model calculations.

  9. The Skyrme-TQRPA calculations of electron capture on hot nuclei in pre-supernova environment

    Energy Technology Data Exchange (ETDEWEB)

    Dzhioev, Alan A., E-mail: dzhioev@theor.jinr.ru; Vdovin, A. I., E-mail: vdovin@theor.jinr.ru [JINR, Bogoliubov Laboratory of Theoretical Physics (Russian Federation); Stoyanov, Ch., E-mail: stoyanov@inrne.bas.bg [Bulgarian Academy of Sciences, Institute for Nuclear Research and Nuclear Energy (Bulgaria)

    2016-11-15

    We combine the thermal QRPA approach with the Skyrme energy density functional theory (Skyrme–TQRPA) for modelling the process of electron capture on nuclei in supernova environment. For a sample nucleus, {sup 56}Fe, the Skyrme–TQRPA approach is applied to analyze thermal effects on the strength function of GT{sub +} transitions which dominate electron capture at E{sub e} ≤ 30 MeV. Several Skyrme interactions are used in order to verify the sensitivity of the obtained results to the Skyrme force parameters. Finite-temperature cross sections are calculated and the results are comparedwith those of the other model calculations.

  10. The Skyrme-TQRPA calculations of electron capture on hot nuclei in pre-supernova environment

    Science.gov (United States)

    Dzhioev, Alan A.; Vdovin, A. I.; Stoyanov, Ch.

    2016-11-01

    We combine the thermal QRPA approach with the Skyrme energy density functional theory (Skyrme-TQRPA) for modelling the process of electron capture on nuclei in supernova environment. For a sample nucleus, 56Fe, the Skyrme-TQRPA approach is applied to analyze thermal effects on the strength function of GT+ transitions which dominate electron capture at E e ≤ 30 MeV. Several Skyrme interactions are used in order to verify the sensitivity of the obtained results to the Skyrme force parameters. Finite-temperature cross sections are calculated and the results are comparedwith those of the other model calculations.

  11. INTEGRATIVE PROPERTIES OF LIBRARY FUNCTIONS: IMPLEMENTATION IN THE EDUCATIONAL ELECTRONIC ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Т. Л. Бірюкова

    2017-02-01

    In our opinion, the use of distance education programs primarily to build interaction of educational and library establishments in the electronic environment. To achieve this goal, through the interaction of the system Library Education created and signed to the practice of teaching subjects at the Documentation and information activities department Odessa National Polytechnic University methodological development, there are student groups whose work promotes the assimilation of theoretical material in practice, just in the information institution, adapting to the professional environment, provided the possibility of passing the full production and pre-diploma practice.

  12. Electrochemical Electron Transfer and Proton-Coupled Electron Transfer: Effects of Double Layer and Ionic Environment on Solvent Reorganization Energies

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Soumya; Soudackov, Alexander; Hammes-Schiffer, Sharon

    2016-06-14

    Electron transfer and proton coupled electron transfer (PCET) reactions at electrochemical interfaces play an essential role in a broad range of energy conversion processes. The reorganization energy, which is a measure of the free energy change associated with solute and solvent rearrangements, is a key quantity for calculating rate constants for these reactions. We present a computational method for including the effects of the double layer and ionic environment of the diffuse layer in calculations of electrochemical solvent reorganization energies. This approach incorporates an accurate electronic charge distribution of the solute within a molecular-shaped cavity in conjunction with a dielectric continuum treatment of the solvent, ions, and electrode using the integral equations formalism polarizable continuum model. The molecule-solvent boundary is treated explicitly, but the effects of the electrode-double layer and double layer-diffuse layer boundaries, as well as the effects of the ionic strength of the solvent, are included through an external Green’s function. The calculated total reorganization energies agree well with experimentally measured values for a series of electrochemical systems, and the effects of including both the double layer and ionic environment are found to be very small. This general approach was also extended to electrochemical PCET and produced total reorganization energies in close agreement with experimental values for two experimentally studied PCET systems. This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences.

  13. Quantum dynamics of electronic excitations in biomolecular chromophores: role of the protein environment and solvent

    CERN Document Server

    Gilmore, J; Gilmore, Joel; Kenzie, Ross H. Mc

    2006-01-01

    We consider continuum dielectric models as minimal models to understand the effect of the surrounding protein and solvent on the quantum dynamics of electronic excitations in a biological chromophore. For these models we describe expressions for the frequency dependent spectral density which describes the coupling of the electronic levels in the chromophore to its environment. We find the contributions to the spectral density from each component of the chromophore environment: the bulk solvent, protein, and water bound to the protein. The relative importance of each component is determined by the time scale on which one is considering the quantum dynamics of the chromophore. Our results provide a natural explanation and model for the different time scales observed in the spectral density extracted from the solvation dynamics probed by ultra-fast laser spectroscopy techniques such as the dynamic Stokes shift and three pulse photon echo spectroscopy. Our results can be used to define under what conditions the d...

  14. Pricing and Ordering Strategies of E-Retailers in Electronic Business Environments

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    It is becoming increasingly evident that in the future the Internet will host large numbers of software agents that aid or even act on behalf of companies and consumers to make decisions and carry out transactions. In this paper, we develop different pricing and ordering strategies with limited information requirements for e-retailers under the electronic business environment, and study the dynamics and performance of these strategies through multi-agent simulation. The results not only reproduce some phenomena in former literature, such as the "tacit collusion" and the cyclical price wars,but also generate new findings, for example, the "tacit collusion" does not always exist among hill-climbing e-retailers, and the cyclical price wars will be suppressed when e-retailers consider their competitors'strategies. The results show that in electronic business environments, to test different strategies and evaluate their performance by simulation before they are employed into practice is of great importance.

  15. Exploration Technology Developments Program's Radiation Hardened Electronics for Space Environments (RHESE) Project Overview

    Science.gov (United States)

    Keys, Andrew S.; Adams, James H.; Darty, Ronald C.; Patrick, Marshall C.; Johnson, Michael A.; Cressler, John D.

    2008-01-01

    Primary Objective: 1) A computational tool to accurately predict electronics performance in the presence of space radiation in support of spacecraft design: a) Total dose; b) Single Event Effects; and c) Mean Time Between Failure. (Developed as successor to CR ME96.) Secondary Objectives: 2) To provide a detailed description of the natural radiation environment in support of radiation health and instrument design: a) In deep space; b) Inside the magnetosphere; and c) Behind shielding.

  16. Evaluation of Groundwater Pollution Nitrogen Fertilizer Using Expert System

    OpenAIRE

    Ta-oun, Mongkon; Daud, Mohamed; Bardaie, Mohd Zohadie

    2017-01-01

    An expert system was used to correlate the availability of nitrogen fertilizer with the vulnerability of groundwater to pollution in Peninsula Malaysia to identify potential groundwater quality problems. The expert system could predict the groundwater pollution potential under several conditions of agricultural activities and exiting environments. Four categories of groundwater pollution potential were identified base on an N-fertilizer groundwater pollution potential index. A groundwater pol...

  17. Effects of electron donors on the microbial reductive dechlorination of hexachlorocyclohexane and on the environment.

    Science.gov (United States)

    Cui, Zhaojie; Meng, Fanli; Hong, Jinglan; Li, Xiangzhi; Ren, Xiaohua

    2012-06-01

    The reductive biotransformation of α-, β-, γ-, and δ-hexachlorocyclohexane isomers was investigated using five alternative electron donors (i.e., glucose plus methanol, glucose only, methanol only, acetate, and ethanol) in a batch assay of an HCH-dechlorinating anaerobic culture. In addition, a life cycle assessment was conducted using the IMPACT2002+ method to evaluate the environmental effects of HCH bioremediation with the aforementioned electron donors. Results showed that the electron donors methanol plus glucose, ethanol, glucose, and methanol can significantly enhance the biotransformation of each HCH isomer. However, the amended electron donors and the byproduct of the anoxic/anaerobic systems may negatively affect the environment (e.g., respiratory inorganic, land occupation, global warming, and non-renewable energy categories). These effects are attributed to the electron donor production processes. To avoid secondary pollutants, a linear relationship between the upper bound electron donor applications and HCH concentration was observed from an environmental perspective. Results indicated that the methanol scenario was the most suitable option for the current research.

  18. Nonrelativistic structure calculations of two-electron ions in a strongly coupled plasma environment

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, S.; Saha, J. K.; Mukherjee, T. K.

    2015-04-01

    In this work, the controversy between the interpretations of recent measurements on dense aluminum plasma created with the Linac coherent light source (LCLS) x-ray free electron laser (FEL) and the Orion laser has been addressed. In both kinds of experiments, heliumlike and hydrogenlike spectral lines are used for plasma diagnostics. However, there exist no precise theoretical calculations for He-like ions within a dense plasma environment. The strong need for an accurate theoretical estimate for spectral properties of He-like ions in a strongly coupled plasma environment leads us to perform ab initio calculations in the framework of the Rayleigh-Ritz variation principle in Hylleraas coordinates where an ion-sphere potential is used. An approach to resolve the long-drawn problem of numerical instability for evaluating two-electron integrals with an extended basis inside a finite domain is presented here. The present values of electron densities corresponding to the disappearance of different spectral lines obtained within the framework of an ion-sphere potential show excellent agreement with Orion laser experiments in Al plasma and with recent theories. Moreover, this method is extended to predict the critical plasma densities at which the spectral lines of H-like and He-like carbon and argon ions disappear. Incidental degeneracy and level-crossing phenomena are being reported for two-electron ions embedded in strongly coupled plasma. Thermodynamic pressure experienced by the ions in their respective ground states inside the ion spheres is also reported.

  19. Development of a prediction model on the acceptance of electronic laboratory notebooks in academic environments.

    Science.gov (United States)

    Kloeckner, Frederik; Farkas, Robert; Franken, Tobias; Schmitz-Rode, Thomas

    2014-04-01

    Documentation of research data plays a key role in the biomedical engineering innovation processes. It makes an important contribution to the protection of intellectual property, the traceability of results and fulfilling the regulatory requirement. Because of the increasing digitalization in laboratories, an electronic alternative to the commonly-used paper-bound notebooks could contribute to the production of sophisticated documentation. However, compared to in an industrial environment, the use of electronic laboratory notebooks is not widespread in academic laboratories. Little is known about the acceptance of an electronic documentation system and the underlying reasons for this. Thus, this paper aims to establish a prediction model on the potential preference and acceptance of scientists either for paper-based or electronic documentation. The underlying data for the analysis originate from an online survey of 101 scientists in industrial, academic and clinical environments. Various parameters were analyzed to identify crucial factors for the system preference using binary logistic regression. The analysis showed significant dependency between the documentation system preference and the supposed workload associated with the documentation system (pnotebook before implementation.

  20. An empirical model of the high-energy electron environment at Jupiter

    Science.gov (United States)

    Soria-Santacruz, M.; Garrett, H. B.; Evans, R. W.; Jun, I.; Kim, W.; Paranicas, C.; Drozdov, A.

    2016-10-01

    We present an empirical model of the energetic electron environment in Jupiter's magnetosphere that we have named the Galileo Interim Radiation Electron Model version-2 (GIRE2) since it is based on Galileo data from the Energetic Particle Detector (EPD). Inside 8RJ, GIRE2 adopts the previously existing model of Divine and Garrett because this region was well sampled by the Pioneer and Voyager spacecraft but poorly covered by Galileo. Outside of 8RJ, the model is based on 10 min averages of Galileo EPD data as well as on measurements from the Geiger Tube Telescope on board the Pioneer spacecraft. In the inner magnetosphere the field configuration is dipolar, while in the outer magnetosphere it presents a disk-like structure. The gradual transition between these two behaviors is centered at about 17RJ. GIRE2 distinguishes between the two different regions characterized by these two magnetic field topologies. Specifically, GIRE2 consists of an inner trapped omnidirectional model between 8 to 17RJ that smoothly joins onto the original Divine and Garrett model inside 8RJ and onto a GIRE2 plasma sheet model at large radial distances. The model provides a complete picture of the high-energy electron environment in the Jovian magnetosphere from ˜1 to 50RJ. The present manuscript describes in great detail the data sets, formulation, and fittings used in the model and provides a discussion of the predicted high-energy electron fluxes as a function of energy and radial distance from the planet.

  1. Submarine groundwater discharge in the Sarasota Bay system: Its assessment and implications for the nearshore coastal environment

    Science.gov (United States)

    Mwashote, B. M.; Murray, M.; Burnett, W. C.; Chanton, J.; Kruse, S.; Forde, A.

    2013-02-01

    A study was conducted from July 2002 through June 2006 in order to assess the significance of submarine groundwater discharge (SGD) to Sarasota Bay (SB), Florida. The assessment approaches used in this study included manual seepage meters, geochemical tracers (radon, 222Rn and methane, CH4), and subseafloor resistivity measurements. The estimated SGD advection rates in the SB system were found to range from 0.7 to 24.0 cm/day, except for some isolated hot spot occurrences where higher rates were observed. In general, SGD estimates were relatively higher (5.9-24.0 cm/day) in the middle and south regions of the bay compared to the north region (0.7-5.9 cm/day). Average dissolved inorganic nutrient concentrations within the SB water column ranged: 0.1-11 μM (NO2+NO3), 0.1-9.1 μM (NH4) and 0.2-1.4 μM (PO4). The average N/P ratio was higher in the north compared to the middle and south regions of the bay. On average, we conservatively estimate that about 27% of the total N in the SB system was derived via SGD. The prevalence of shallow embayed areas in the SB system and the presence of numerous septic tanks in the surrounding settlements enhanced the potential effects of nutrient rich seepages. Statistical comparison of the quantitative approaches revealed a good agreement between SGD estimates from manual seepage meters and those derived from the 222Rn model (p=0.67; α=0.05; n=18). CH4 was found to be useful for qualitative SGD assessments. CH4 and 222Rn were correlated (r2=0.31; α=0.05; n=54). Large scale resistivity surveys showed spatial variability that correlates more clearly with lithology than with SGD patterns.

  2. A harsh environment wireless pressure sensing solution utilizing high temperature electronics.

    Science.gov (United States)

    Yang, Jie

    2013-02-27

    Pressure measurement under harsh environments, especially at high temperatures, is of great interest to many industries. The applicability of current pressure sensing technologies in extreme environments is limited by the embedded electronics which cannot survive beyond 300 °C ambient temperature as of today. In this paper, a pressure signal processing and wireless transmission module based on the cutting-edge Silicon Carbide (SiC) devices is designed and developed, for a commercial piezoresistive MEMS pressure sensor from Kulite Semiconductor Products, Inc. Equipped with this advanced high-temperature SiC electronics, not only the sensor head, but the entire pressure sensor suite is capable of operating at 450 °C. The addition of wireless functionality also makes the pressure sensor more flexible in harsh environments by eliminating the costly and fragile cable connections. The proposed approach was verified through prototype fabrication and high temperature bench testing from room temperature up to 450 °C. This novel high-temperature pressure sensing technology can be applied in real-time health monitoring of many systems involving harsh environments, such as military and commercial turbine engines.

  3. Best Practices Regarding the Use of Electronic Environment for Romanian Tourism Development

    Directory of Open Access Journals (Sweden)

    Irina Maiorescu

    2016-05-01

    Full Text Available Information and Communication Technology (ICT plays an important role in all sectors of activity, hence in tourism sector too. Starting from this fact, authors consider as important identifying and implementing best practices in electronic environment for sustainable development of tourism in Romania. Traditional tourism - implying at all stages specialized human support – knows profound modifications. Today, current statistics show that more and more people dive into virtual environment for visualizing new places and finding out new information, for cross border business meetings, for entertainment as well as for communication. Hence, the current paper – presenting the results of a complex quantitative research, aims to discuss about the influence of virtual environment upon tourism in what concerns informing, planning and organizing a trip. The obtained results led towards recommendations for developing ICT facilities, especially for business tourism, for an extensive use of web-GIS applications during the three phases of travel, for improving infrastructure and mobile applications, especially for young people, as well as for implementing digital systems that investigate tourists’ behaviour and personalize tourism offers. The final purpose of the paper is to contribute to the development of best practices that lead to economic growth in tourism, by quantifying the impact of electronic environment upon visiting experiences.

  4. A Harsh Environment Wireless Pressure Sensing Solution Utilizing High Temperature Electronics

    Directory of Open Access Journals (Sweden)

    Jie Yang

    2013-02-01

    Full Text Available Pressure measurement under harsh environments, especially at high temperatures, is of great interest to many industries. The applicability of current pressure sensing technologies in extreme environments is limited by the embedded electronics which cannot survive beyond 300 °C ambient temperature as of today. In this paper, a pressure signal processing and wireless transmission module based on the cutting-edge Silicon Carbide (SiC devices is designed and developed, for a commercial piezoresistive MEMS pressure sensor from Kulite Semiconductor Products, Inc. Equipped with this advanced high-temperature SiC electronics, not only the sensor head, but the entire pressure sensor suite is capable of operating at 450 °C. The addition of wireless functionality also makes the pressure sensor more flexible in harsh environments by eliminating the costly and fragile cable connections. The proposed approach was verified through prototype fabrication and high temperature bench testing from room temperature up to 450 °C. This novel high-temperature pressure sensing technology can be applied in real-time health monitoring of many systems involving harsh environments, such as military and commercial turbine engines.

  5. Electronic Informational and Educational Environment as a Factor of Competence-Oriented Higher Pedagogical Education in the Sphere of Health, Safety and Environment

    Science.gov (United States)

    Kamerilova, Galina S.; Kartavykh, Marina A.; Ageeva, Elena L.; Veryaskina, Marina A.; Ruban, Elena M.

    2016-01-01

    The authors consider the question of computerisation in health, safety and environment teachers' training in the context of the general approaches and requirements of the Federal National Standard of Higher Education, which is realised through designing of electronic informational and educational environment. The researchers argue indispensability…

  6. Qualification of electronic components and systems in a LHC Tunnel Radiation Environment

    CERN Document Server

    Rausch, R; Wijnands, Thijs

    2002-01-01

    Around 10.200 electronic crates will be installed in the LHC underground areas of which some 4.200 will be connected to the machine control network. Some of the electronic equipment will be housed under the cryostats of the main dipoles inside the tunnel. Other equipment will be placed alongside the tunnel, in the alcoves or in galleries parallel to the machine. In the regular arcs and in the dispersion suppressors areas the expected annual dose is low, i.e. only a few Gy/y. However, preliminary radiation tests showed that electronic equipment fails even at such low dose rates. Since radiation qualification of all tunnel electronics is essential in order to guarantee its reliable operation over the lifetime of the machine, a LHC radiation test facility was commissioned in the North Experimental Area of the SPS accelerator. This paper presents the simulation study concerning the radiation environment of the LHC Radiation Test Facility and gives an overview of the various underground electronic systems as they ...

  7. Chemical changes in groundwater due to flooding of an iron mine in a non-acid producing environment

    OpenAIRE

    Collon, Pauline,; Fabriol, Robert; Bues, Michel

    2002-01-01

    International audience; Mine drainage is one of the mining industry’s undesirable effects on the environment. Mining operations disturb the chemical equilibrium of the surrounding rocks by suddenly exposing them to oxidising conditions. The chemical reactions that take place generate effluents that are usually acidic and contain SO42-, Fe, Mn, etc. After the mines are closed and abandoned, the suspension of dewatering and drainage leads to progressive flooding of the workings. The waters drai...

  8. High-fluoride groundwater.

    Science.gov (United States)

    Rao, N Subba

    2011-05-01

    Fluoride (F(-)) is essential for normal bone growth, but its higher concentration in the drinking water poses great health problems and fluorosis is common in many parts of India. The present paper deals with the aim of establishment of facts of the chemical characteristics responsible for the higher concentration of F(-) in the groundwater, after understanding the chemical behavior of F(-) in relation to pH, total alkalinity (TA), total hardness (TH), carbonate hardness (CH), non-carbonate hardness (NCH), and excess alkalinity (EA) in the groundwater observed from the known areas of endemic fluorosis zones of Andhra Pradesh that have abundant sources of F(-)-bearing minerals of the Precambrians. The chemical data of the groundwater shows that the pH increases with increase F(-); the concentration of TH is more than the concentration of TA at low F(-) groundwater, the resulting water is represented by NCH; the TH has less concentration compared to TA at high F(-) groundwater, causing the water that is characterized by EA; and the water of both low and high concentrations of F(-) has CH. As a result, the F(-) has a positive relation with pH and TA, and a negative relation with TH. The operating mechanism derived from these observations is that the F(-) is released from the source into the groundwater by geochemical reactions and that the groundwater in its flowpath is subjected to evapotranspiration due to the influence of dry climate, which accelerates a precipitation of CaCO(3) and a reduction of TH, and thereby a dissolution of F(-). Furthermore, the EA in the water activates the alkalinity in the areas of alkaline soils, leading to enrichment of F(-). Therefore, the alkaline condition, with high pH and EA, and low TH, is a more conducive environment for the higher concentration of F(-) in the groundwater.

  9. PREFACE: India-Japan Workshop on Biomolecular Electronics & Organic Nanotechnology for Environment Preservation

    Science.gov (United States)

    Onoda, Mitsuyoshi; Malhotra, Bansi D.

    2012-04-01

    The 'India-Japan Workshop on Biomolecular Electronics & Organic Nanotechnology for Environment Preservation' (IJWBME 2011) will be held on 7-10 December 2011 at EGRET Himeji, Himeji, Hyogo, Japan. This workshop was held for the first time on 17-19 December 2009 at NPL, New Delhi. Keeping in mind the importance of organic nanotechnology and biomolecular electronics for environmental preservation and their anticipated impact on the economics of both the developing and the developed world, IJWBME 2009 was jointly organized by the Department of Biological Functions, Graduate School of Life Sciences and Systems Engineering, the Kyushu Institute of Technology (KIT), Kitakyushu, Japan, and the Department of Science & Technology Centre on Biomolecular Electronics (DSTCBE), National Physical Laboratory (NPL). Much progress in the field of biomolecular electronics and organic nanotechnology for environmental preservation is expected for the 21st Century. Organic optoelectronic devices, such as organic electroluminescent devices, organic thin-film transistors, organic sensors, biological systems and so on have especially attracted much attention. The main purpose of this workshop is to provide an opportunity for researchers interested in biomolecular electronics and organic nanotechnology for environmental preservation, to come together in an informal and friendly atmosphere and exchange technical knowledge and experience. We are sure that this workshop will be very useful and fruitful for all participants in summarizing the recent progress in biomolecular electronics and organic nanotechnology for environmental preservation and preparing new ground for the next generation. Many papers have been submitted from India and Japan and more than 30 papers have been accepted for presentation. The main topics of interest are as follows: Bioelectronics Biomolecular Electronics Fabrication Techniques Self-assembled Monolayers Nano-sensors Environmental Monitoring Organic Devices

  10. Electronic waste – an emerging threat to the environment of urban India

    Science.gov (United States)

    2014-01-01

    Electronic waste or e-waste is one of the emerging problems in developed and developing countries worldwide. It comprises of a multitude of components with valuable materials, some containing toxic substances, that can have an adverse impact on human health and the environment. Previous studies show that India has generated 0.4 million tons of e-waste in 2010 which may increase to 0.5 to 0.6 million tons by 2013–2014. Coupled with lack of appropriate infrastructural facilities and procedures for its disposal and recycling have posed significant importance for e-waste management in India. In general, e-waste is generated through recycling of e-waste and also from dumping of these wastes from other countries. More of these wastes are ending up in dumping yards and recycling centers, posing a new challenge to the environment and policy makers as well. In general electronic gadgets are meant to make our lives happier and simpler, but the toxicity it contains, their disposal and recycling becomes a health nightmare. Most of the users are unaware of the potential negative impact of rapidly increasing use of computers, monitors, and televisions. This review article provides a concise overview of India’s current e-waste scenario, namely magnitude of the problem, environmental and health hazards, current disposal, recycling operations and mechanisms to improve the condition for better environment. PMID:24444377

  11. Electronic waste - an emerging threat to the environment of urban India.

    Science.gov (United States)

    Needhidasan, Santhanam; Samuel, Melvin; Chidambaram, Ramalingam

    2014-01-20

    Electronic waste or e-waste is one of the emerging problems in developed and developing countries worldwide. It comprises of a multitude of components with valuable materials, some containing toxic substances, that can have an adverse impact on human health and the environment. Previous studies show that India has generated 0.4 million tons of e-waste in 2010 which may increase to 0.5 to 0.6 million tons by 2013-2014. Coupled with lack of appropriate infrastructural facilities and procedures for its disposal and recycling have posed significant importance for e-waste management in India. In general, e-waste is generated through recycling of e-waste and also from dumping of these wastes from other countries. More of these wastes are ending up in dumping yards and recycling centers, posing a new challenge to the environment and policy makers as well. In general electronic gadgets are meant to make our lives happier and simpler, but the toxicity it contains, their disposal and recycling becomes a health nightmare. Most of the users are unaware of the potential negative impact of rapidly increasing use of computers, monitors, and televisions. This review article provides a concise overview of India's current e-waste scenario, namely magnitude of the problem, environmental and health hazards, current disposal, recycling operations and mechanisms to improve the condition for better environment.

  12. Future groundwater extraction scenarios for an aquifer in a semiarid environment: case study of Guadalupe Valley Aquifer, Baja California, Northwest Mexico.

    Science.gov (United States)

    Campos-Gaytan, Jose Ruben; Kretzschmar, Thomas; Herrera-Oliva, Claudia Soledad

    2014-11-01

    Semiarid northwestern Mexico presents a growing water demand produced by agricultural and domestic requirements during the last two decades. The community of Guadalupe Valley and the city of Ensenada rely on groundwater pumping from the local aquifer as its sole source of water supply. This dependency has resulted in an imbalance between groundwater pumpage and natural recharge. A two-dimensional groundwater flow model was applied to the Guadalupe Valley Aquifer, which was calibrated and validated for the period 1984-2005. The model analysis verified that groundwater levels in the region are subject to steep declines due to decades of intensive groundwater exploitation for agricultural and domestic purposes. The calibrated model was used to assess the effects of different water management scenarios for the period 2007-2025. If the base case (status quo) scenario continues, groundwater levels are in a continuous drawdown trend. Some wells would run dry by August 2017, and water demand may not be met without incurring in an overdraft. The optimistic scenario implies the achievement of the mean groundwater recharge and discharge. Groundwater level depletion could be stopped and restored. The sustainable scenario implies the reduction of current extraction (up to about 50 %), when groundwater level depletion could be stopped. A reduction in current extraction mitigates water stress in the aquifer but cannot solely reverse declining water tables across the region. The combination of reduced current extraction and an implemented alternative solution (such as groundwater artificial recharge), provides the most effective measure to stabilize and reverse declining groundwater levels while meeting water demands in the region.

  13. On the role of the gas environment, electron-dose-rate, and sample on the image resolution in transmission electron microscopy

    DEFF Research Database (Denmark)

    Ek, Martin; Jespersen, Sebastian Pirel Fredsgaard; Damsgaard, Christian Danvad;

    2016-01-01

    The introduction of gaseous atmospheres in transmission electron microscopy offers the possibility of studying materials in situ under chemically relevant environments. The presence of a gas environment can degrade the resolution. Surprisingly, this phenomenon has been shown to depend on the elec...

  14. 40 CFR 257.22 - Ground-water monitoring systems.

    Science.gov (United States)

    2010-07-01

    ... operator. When physical obstacles preclude installation of ground-water monitoring wells at the relevant... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water......

  15. 不同地下水埋深污灌硝态氮对土壤-地下水环境影响试验研究%Research on nitrate to negative effect of soil and groundwater environment at different groundwater depth with sewage irrigation

    Institute of Scientific and Technical Information of China (English)

    刘伟佳; 吴军虎; 彭忠福

    2012-01-01

    Groundwater depth is one of main factors affecting the migration of sewage irrigation pollutants in soil and groundwater system.This paper analyzed the transportation characteristic of nitrate in soil and groundwater under different groundwater depth through laboratory experiments with sewage irrigation.The results indicated that the effects of different groundwater depth on soil and groundwater environment,including the distribution of soil water and migration path of nitrate,were significant.Under the lower groundwater depth,although the higher soil moisture potential energy and denitrification restrict the migration tendency of nitrate in sewage from up to down,the higher soil moisture potential energy and shorter migration path make it easy for the nitrate of soil matrix to be pushed from subsoil to groundwater,then the pollution risk of groundwater increased.%地下水埋深是影响污灌污染物在土壤-地下水系统中运移特性的主要因素之一。通过室内污水入渗试验,研究了不同地下水埋深条件下污灌污染物NO3--N在土壤中的运移特性及对地下水环境的影响。研究结果表明:地下水埋深的不同导致了土壤内水分分布和NO3--N迁移路径的差异,从而影响了NO3--N在土壤-地下水系统中的运移特性。埋深浅,高土水势能和反硝化潜势制约了污水携带NO3--N向下层土壤迁移淋失的趋势,但高土水势能和短迁移路径使下层土壤基质中的NO3--N易被挤入至地下水中,NO3--N污染地下水风险较大。

  16. Electron-induced hydrogen loss in uracil in a water cluster environment

    Energy Technology Data Exchange (ETDEWEB)

    Smyth, M.; Kohanoff, J. [Atomistic Simulation Centre, Queen' s University Belfast, Belfast BT7 1NN, Northern Ireland (United Kingdom); Fabrikant, I. I., E-mail: ifabrikant1@unl.edu [Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588, USA and Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)

    2014-05-14

    Low-energy electron-impact hydrogen loss due to dissociative electron attachment (DEA) to the uracil and thymine molecules in a water cluster environment is investigated theoretically. Only the A{sup ′}-resonance contribution, describing the near-threshold behavior of DEA, is incorporated. Calculations are based on the nonlocal complex potential theory and the multiple scattering theory, and are performed for a model target with basic properties of uracil and thymine, surrounded by five water molecules. The DEA cross section is strongly enhanced when the attaching molecule is embedded in a water cluster. This growth is due to two effects: the increase of the resonance lifetime and the negative shift in the resonance position due to interaction of the intermediate negative ion with the surrounding water molecules. A similar effect was earlier found in DEA to chlorofluorocarbons.

  17. A Problem Solving Environment for Electronic Commerce and Collaborative Work in the Housing Industry of China

    Institute of Scientific and Technical Information of China (English)

    XUJungang; WANGHongan; DAIGuozhong

    2004-01-01

    Currently, the world is in the times that knowledge economy is growing up rapidly. The gathering, sharing, using and spreading of information have become key factors of influencing competition capability of one enterprise; at the same time, information technologies that support distributed computing and information sharing appear one after the other. Therefore, distributed computing will become an inevitable trend of development of enterprise informatization. As one part of the construction industry, the housing industry is emerging as a new application frontier for information technologies. According to the applications of information technologies in the housing industry, this paper puts forth a Problem Solving Environment for electronic commerce and collaborative work, electronic-PSE (e-PSE), which is an Intranet/Internet platform for solving many problems existing in the housing industry, such as building of virtual organization, system integration, development of new Internet/Intranet application and so on. The information infrastructure framework of e-PSE is presented, whichi ncludes two modules: XML-based electronic commerce platform (XECP), XML-based collaborative work platform(XCWP). XECP provides solutions for integration of construction system and electronic commerce system; XCWP provides solutions for building of virtual organization and implementation of collaborative work of partners. At last,conclusions and prospects are presented.

  18. Electronic waste – an emerging threat to the environment of urban India

    OpenAIRE

    Needhidasan, Santhanam; Samuel, Melvin; Chidambaram, Ramalingam

    2014-01-01

    Electronic waste or e-waste is one of the emerging problems in developed and developing countries worldwide. It comprises of a multitude of components with valuable materials, some containing toxic substances, that can have an adverse impact on human health and the environment. Previous studies show that India has generated 0.4 million tons of e-waste in 2010 which may increase to 0.5 to 0.6 million tons by 2013–2014. Coupled with lack of appropriate infrastructural facilities and procedures ...

  19. Determining the most suitable areas for artificial groundwater recharge via an integrated PROMETHEE II-AHP method in GIS environment (case study: Garabaygan Basin, Iran).

    Science.gov (United States)

    Nasiri, Hossein; Boloorani, Ali Darvishi; Sabokbar, Hassan Ali Faraji; Jafari, Hamid Reza; Hamzeh, Mohamad; Rafii, Yusef

    2013-01-01

    Flood spreading is a suitable strategy for controlling and benefiting from floods. Selecting suitable areas for flood spreading and directing the floodwater into permeable formations are amongst the most effective strategies in flood spreading projects. Having combined geographic information systems (GIS) and multi-criteria decision analysis approaches, the present study sought to locate the most suitable areas for flood spreading operation in the Garabaygan Basin of Iran. To this end, the data layers relating to the eight effective factors were prepared in GIS environment. This stage was followed by elimination of the exclusionary areas for flood spreading while determining the potentially suitable ones. Having closely examined the potentially suitable areas using the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) II and analytic hierarchy process (AHP) methods, the land suitability map for flood spreading was produced. The PROMETHEE II and AHP were used for ranking all the alternatives and weighting the criteria involved, respectively. The results of the study showed that most suitable areas for the artificial groundwater recharge are located in Quaternary Q(g) and Q(gsc) geologic units and in geomorphological units of pediment and Alluvial fans with slopes not exceeding 3%. Furthermore, significant correspondence between the produced map and the control areas, where the flood spreading projects were successfully performed, provided further evidence for the acceptable efficiency of the integrated PROMETHEE II-AHP method in locating suitable flood spreading areas.

  20. In situ groundwater bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, Terry C.

    2009-02-01

    In situ groundwater bioremediation of hydrocarbons has been used for more than 40 years. Most strategies involve biostimulation; however, recently bioaugmentation have been used for dehalorespiration. Aquifer and contaminant profiles are critical to determining the feasibility and strategy for in situ groundwater bioremediation. Hydraulic conductivity and redox conditions, including concentrations of terminal electron acceptors are critical to determine the feasibility and strategy for potential bioremediation applications. Conceptual models followed by characterization and subsequent numerical models are critical for efficient and cost effective bioremediation. Critical research needs in this area include better modeling and integration of remediation strategies with natural attenuation.

  1. Effects of Heterogeneous Vadose Zone Thickness on Spatial and Temporal Groundwater Recharge Characteristics in Dune Environments: An Example from the Nebraska Sand Hills

    Science.gov (United States)

    Zlotnik, V. A.; Rossman, N. R.; Rowe, C. M.; Szilagyi, J.

    2013-12-01

    We investigate effects of land surface topography on the spatial and temporal distribution of groundwater recharge (GWR). Such effects are important for groundwater modeling, analysis of climate change impacts, and water resources management. Typically, climate changes are investigated on multi-decadal to centennial time scales. However, travel times of soil moisture across the vadose zone vary broadly, extending to multi-centennial periods in arid and semi-arid environments. For given climatic conditions on the land surface, we evaluate travel times in thick vadose zones and compare with climate change time scales. This comparison allows determination of the land surface areas contributing to GWR changes where travel times are shorter than climate change time scales. In areas with travel times longer than climate change time scales, GWR remains unchanged over the considered period of water resources management. Such analysis allows separating the effect of land surface topography from that of spatial and temporal climate variations. Our travel time calculations, based on vertical velocity of the pressure pulse from the land surface, are equivalent to a kinematic wave approximation of Richards' equation. The underlying assumptions (unit head gradients over the entire soil profile and relatively small magnitude of climate changes on the surface) are supported by observations in the High Plains Aquifer region. The computations require a DEM of land surface topography, mapped water table elevations, mapped climate variables on the land surface (IPCC 2007, CMIP3, hydrologic VIC model outputs), and estimates of vadose zone hydraulic conductivity as a function of soil moisture content from pedotransfer functions. The method to generate future GWR estimates includes 4 steps: (1) GIS analysis of vadose zone thickness using DEM and water table map; (2) evaluation of deep drainage based on difference between precipitation and evapotranspiration rates (PRISM and MODIS

  2. Modeling and sensitivity analysis of electron capacitance for Geobacter in sedimentary environments.

    Science.gov (United States)

    Zhao, Jiao; Fang, Yilin; Scheibe, Timothy D; Lovley, Derek R; Mahadevan, R

    2010-03-01

    In situ stimulation of the metabolic activity of Geobacter species through acetate amendment has been shown to be a promising bioremediation strategy to reduce and immobilize hexavalent uranium [U(VI)] as insoluble U(IV). Although Geobacter species are reducing U(VI), they primarily grow via Fe(III) reduction. Unfortunately, the biogeochemistry and the physiology of simultaneous reduction of multiple metals are still poorly understood. A detailed model is therefore required to better understand the pathways leading to U(VI) and Fe(III) reduction by Geobacter species. Based on recent experimental evidence of temporary electron capacitors in Geobacter we propose a novel kinetic model that physically distinguishes planktonic cells into electron-loaded and -unloaded states. Incorporation of an electron load-unload cycle into the model provides insight into U(VI) reduction efficiency, and elucidates the relationship between U(VI)- and Fe(III)-reducing activity and further explains the correlation of high U(VI) removal with high fractions of planktonic cells in subsurface environments. Global sensitivity analysis was used to determine the level of importance of geochemical and microbial processes controlling Geobacter growth and U(VI) reduction, suggesting that the electron load-unload cycle and the resulting repartition of the microbes between aqueous and attached phases are critical for U(VI) reduction. As compared with conventional Monod modeling approaches without inclusion of the electron capacitance, the new model attempts to incorporate a novel cellular mechanism that has a significant impact on the outcome of in situ bioremediation.

  3. Alpha decay in electron environments of increasing density: From the bare nucleus to compressed matter

    Energy Technology Data Exchange (ETDEWEB)

    Belloni, Fabio [Institute for Transuranium Elements, European Commission, Joint Research Centre, Postfach 2340, Karlsruhe (Germany)

    2016-02-15

    The influence of the electron environment on the α decay is elucidated. Within the frame of a simple model based on the generalized Thomas-Fermi theory of the atom, it is shown that the increase of the electron density around the parent nucleus drives a mechanism which shortens the lifetime. Numerical results are provided for {sup 144}Nd, {sup 154}Yb and {sup 210}Po. Depending on the nuclide, fractional lifetime reduction relative to the bare nucleus is of the order of 0.1-1% in free ions, neutral atoms and ordinary matter, but may reach up to 10% at matter densities as high as 10{sup 4}g/cm{sup 3}, in a high-Z matrix. The effect induced by means of state-of-the-art compression techniques, although much smaller than previously found, would however be measurable. The extent of the effect in ultra-high-density stellar environments might become significant and would deserve further investigation. (orig.)

  4. Power electronics performance in cryogenic environment: evaluation for use in HTS power devices

    Science.gov (United States)

    Pereira, P.; Valtchev, S.; Pina, J.; Gonçalves, A.; Ventim Neves, M.; Rodrigues, A. L.

    2008-02-01

    Power electronics (PE) plays a major role in electrical devices and systems, namely in electromechanical drives, in motor and generator controllers, and in power grids, including high-voltage DC (HVDC) power transmission. PE is also used in devices for the protection against grid disturbances, like voltage sags or power breakdowns. To cope with these disturbances, back-up energy storage devices are used, like uninterruptible power supplies (UPS) and flywheels. Some of these devices may use superconductivity. Commercial PE semiconductor devices (power diodes, power MOSFETs, IGBTs, power Darlington transistors and others) are rarely (or never) experimented for cryogenic temperatures, even when designed for military applications. This means that its integration with HTS power devices is usually done in the hot environment, raising several implementation restrictions. These reasons led to the natural desire of characterising PE under extreme conditions, e. g. at liquid nitrogen temperatures, for use in HTS devices. Some researchers expect that cryogenic temperatures may increase power electronics' performance when compared with room-temperature operation, namely reducing conduction losses and switching time. Also the overall system efficiency may increase due to improved properties of semiconductor materials at low temperatures, reduced losses, and removal of dissipation elements. In this work, steady state operation of commercial PE semiconductors and devices were investigated at liquid nitrogen and room temperatures. Performances in cryogenic and room temperatures are compared. Results help to decide which environment is to be used for different power HTS applications.

  5. ANALYSIS OF DOMESTIC AND INTERNATIONAL APPROACHES TO THE ADVANCED EDUCATIONAL PRACTICES IN THE ELECTRONIC NETWORK ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Tatiana N. Noskova

    2016-12-01

    Full Text Available Introduction: human activities related to the use of information are being transformed under the influence of computer technology. Variable solutions to information problems are emerging; demands and require¬ments for the competence are changing on the labour market. Educational practices are destined to form a new learning behaviour for the 21st century, adopting lifelong learning strategy. The main purpose of the article is to answer the question as to how to transform existing pedagogical theory and practice under current conditions of electronic environment. Publishing of this article is coherent with concept of the journal Integration of Education, analyzing Russian and world experience in the development of education systems. This approach is important for dissemination and implementation in practice. This article explores the challenges of information technology and technical support of the educational process in universities and schools. The study of these issues is in the field of view of the journa l. Materials and Methods: the paper elaborates on the results of domestic and international educational theory and practice, comparison methods, drawing on student’s survey in the framework of international research in the field of e-learning in higher education institutions. Results: the main approaches, applied to the formulation of educational practices in the electronic environ-ment, were analyzed. The most topical national approaches include system, activity, polysubject (dialogical, context, and dialogical ones. Among international approaches self-directed learning, educational communication strategies, experiential learning, training in partnership, collaborative learning, learning in online communities, situational training were analyzed. Specifics of electronic educational interactions with distributed in time and space activities of teachers and students, create the preconditions for the implementation of new educational

  6. Geo-electrical investigation of near surface conductive structures suitable for groundwater accumulation in a resistive crystalline basement environment: A case study of Isuada, southwestern Nigeria

    Science.gov (United States)

    Kayode, J. S.; Adelusi, A. O.; Nawawi, M. N. M.; Bawallah, M.; Olowolafe, T. S.

    2016-07-01

    This paper presents a geophysical surveying for groundwater identification in a resistive crystalline basement hard rock in Isuada area, Southwestern Nigeria. Very low frequency (VLF) electromagnetic and electrical resistivity geophysical techniques combined with well log were used to characterize the concealed near surface conductive structures suitable for groundwater accumulation. Prior to this work; little was known about the groundwater potential of this area. Qualitative and semi-quantitative interpretations of the data collected along eight traverses at 20 m spacing discovered conductive zones suspected to be fractures, faults, and cracks which were further mapped using Vertical Electrical Sounding (VES) technique. Forty VES stations were utilized using Schlumberger configurations with AB/2 varying from 1 to 100 m. Four layers i.e. the top soil, the weathered layer, the partially weathered/fractured basement and the fresh basement were delineated from the interpreted resistivity curves. The weathered layers constitute the major aquifer unit in the area and are characterized by moderately low resistivity values which ranged between about 52 Ωm and 270 Ωm while the thickness varied from 1 to 35 m. The depth to the basement and the permeable nature of the weathered layer obtained from both the borehole and the hand-dug wells was used to categorize the groundwater potential of the study area into high, medium and low ratings. The groundwater potential map revealed that about 45% of the study area falls within the low groundwater potential rating while about 10% constitutes the medium groundwater potential and the remaining 45% constitutes high groundwater potential. The low resistivity, thick overburden, and fractured bedrock constitute the aquifer units and the series of basement depressions identified from the geoelectric sections as potential conductive zones appropriate for groundwater development.

  7. ELECTRONIC TEXTBOOK — SUBJECT INFORMATIONEDUCATIONAL ENVIRONMENT OF INDEPENDENT WORK OF STUDENTS

    Directory of Open Access Journals (Sweden)

    Elena O. Ivanova

    2015-01-01

    Full Text Available The aim of the paper is to consider the characteristics of the electronic textbook as the subject of the information-educational environment, which ensures the unity both of the procedural and substantive aspects of training.Results. The evolution of views on the electronic textbook in the course of the expansion and awareness of the didactic potential of information and communication technologies is shown. The structure of the electronic textbook is presented in the paper. It includes the following modules: information (invariant content of education and the expansion of its variability; organizational and procedural (variable-based assignments aimed at acquiring information, as well as a means of reflection and evaluation of results; personal (information and telecommunication means of organizing own knowledge; communicative (the field of information and assessment of interaction; and pedagogical (monitoring cognitive activity of students. The structure has been developed with due regard to the need of independent work of a student with the content of education in information and educational environment.Scientific novelty. The features of the independent work of the student in terms of abundance of information through information and communication technologies are analyzed. Special attention is paid to the development of independent cognitive activity of students, their subject position in education. On this bases, the key position that should be considered during the development of the electronic textbook are specified: cognitive activity is considered as an active process of constructing students’ new knowledge based on earlier formed personal experience; personal experience arises as a result of intellectual and cognitive activity of the student; cognition of something new requires an activity in the field of social communication; the efficiency of absorption of the content of education depends on the conditions of implementation of each

  8. ELECTRONIC TEXTBOOK — SUBJECT INFORMATIONEDUCATIONAL ENVIRONMENT OF INDEPENDENT WORK OF STUDENTS

    Directory of Open Access Journals (Sweden)

    Elena O. Ivanova

    2015-06-01

    Full Text Available The aim of the paper is to consider the characteristics of the electronic textbook as the subject of the information-educational environment, which ensures the unity both of the procedural and substantive aspects of training.Results. The evolution of views on the electronic textbook in the course of the expansion and awareness of the didactic potential of information and communication technologies is shown. The structure of the electronic textbook is presented in the paper. It includes the following modules: information (invariant content of education and the expansion of its variability; organizational and procedural (variable-based assignments aimed at acquiring information, as well as a means of reflection and evaluation of results; personal (information and telecommunication means of organizing own knowledge; communicative (the field of information and assessment of interaction; and pedagogical (monitoring cognitive activity of students. The structure has been developed with due regard to the need of independent work of a student with the content of education in information and educational environment.Scientific novelty. The features of the independent work of the student in terms of abundance of information through information and communication technologies are analyzed. Special attention is paid to the development of independent cognitive activity of students, their subject position in education. On this bases, the key position that should be considered during the development of the electronic textbook are specified: cognitive activity is considered as an active process of constructing students’ new knowledge based on earlier formed personal experience; personal experience arises as a result of intellectual and cognitive activity of the student; cognition of something new requires an activity in the field of social communication; the efficiency of absorption of the content of education depends on the conditions of implementation of each

  9. The Development of Electronic Educational Environment of the Contemporary Higher Educational Institution within the Context of Teaching Innovations

    Science.gov (United States)

    Khairova, Irina V.; Toktarova, Vera I.

    2016-01-01

    The problem under study is acute due to rampant development of electronic education putting forward new demands to the arrangement of professional education of HEI students. The article makes a review of innovative means and technologies contributing to the perfection of instructional design of new-generation electronic educational environment.…

  10. High Performance Processors for Space Environments: A Subproject of the NASA Exploration Missions Systems Directorate "Radiation Hardened Electronics for Space Environments" Technology Development Program

    Science.gov (United States)

    Johnson, M.; Label, K.; McCabe, J.; Powell, W.; Bolotin, G.; Kolawa, E.; Ng, T.; Hyde, D.

    2007-01-01

    Implementation of challenging Exploration Systems Missions Directorate objectives and strategies can be constrained by onboard computing capabilities and power efficiencies. The Radiation Hardened Electronics for Space Environments (RHESE) High Performance Processors for Space Environments project will address this challenge by significantly advancing the sustained throughput and processing efficiency of high-per$ormance radiation-hardened processors, targeting delivery of products by the end of FY12.

  11. Reverse ion exchange as a major process controlling the groundwater chemistry in an arid environment: a case study from northwestern Saudi Arabia.

    Science.gov (United States)

    Zaidi, Faisal K; Nazzal, Yousef; Jafri, Muhammad Kamran; Naeem, Muhammad; Ahmed, Izrar

    2015-10-01

    Assessment of groundwater quality is of utmost significance in arid regions like Saudi Arabia where the lack of present-day recharge and high evaporation rates coupled with increasing groundwater withdrawal may restrict its usage for domestic or agricultural purposes. In the present study, groundwater samples collected from agricultural farms in Hail (15 samples), Al Jawf (15 samples), and Tabuk (30 samples) regions were analyzed for their major ion concentration. The objective of the study was to determine the groundwater facies, the main hydrochemical process governing the groundwater chemistry, the saturation index with respect to the principal mineral phases, and the suitability of the groundwater for irrigational use. The groundwater samples fall within the Ca-Cl type, mixed Ca-Mg-Cl type, and Na-Cl type. Evaporation and reverse ion exchange appear to be the major processes controlling the groundwater chemistry though reverse ion exchange process is the more dominating factor. The various ionic relationships confirmed the reverse ion exchange process where the Ca and Mg in the aquifer matrix have been replaced by Na at favorable exchange sites. This phenomenon has accounted for the dominance of Ca and Mg ions over Na ion at all the sites. The process of reverse ion exchange was further substantiated by the use of modified Piper diagram (Chadha's classification) and the chloro-alkaline indices. Evaporation as a result of extreme aridity has resulted in the groundwater being oversaturated with aragonite/calcite and dolomite as revealed by the saturation indices. The groundwater samples were classified as safe (less than 10) in terms of sodium adsorption ratio (SAR) values, good (less than 1.25) in terms of residual sodium carbonate (RSC) values, and safe to moderate (between 0 and 3) in terms of Mg hazard for irrigation purposes. Though the high salinity groundwater in the three regions coupled with low SAR values are good for the soil structure, it can have a

  12. Environment

    DEFF Research Database (Denmark)

    Valentini, Chiara

    2017-01-01

    The term environment refers to the internal and external context in which organizations operate. For some scholars, environment is defined as an arrangement of political, economic, social and cultural factors existing in a given context that have an impact on organizational processes and structures....... For others, environment is a generic term describing a large variety of stakeholders and how these interact and act upon organizations. Organizations and their environment are mutually interdependent and organizational communications are highly affected by the environment. This entry examines the origin...... and development of organization-environment interdependence, the nature of the concept of environment and its relevance for communication scholarships and activities....

  13. GROUNDWATER RECHARGE AND CHEMICAL ...

    Science.gov (United States)

    The existing knowledge base regarding the presence and significance of chemicals foreign to the subsurface environment is large and growing -the papers in this volume serving as recent testament. But complex questions with few answers surround the unknowns regarding the potential for environmental or human health effects from trace levels of xenobiotics in groundwater, especially groundwater augmented with treated wastewater. Public acceptance for direct or indirect groundwater recharge using treated municipal wastewater ( especially sewage) spans the spectrum from unquestioned embrace to outright rejection. In this article, I detour around the issues most commonly discussed for groundwater recharge and instead focus on some of the less-recognized issues- those that emanate from the mysteries created at the many literal and virtual interfaces involved with the subsurface world. My major objective is to catalyze discussion that advances our understanding of the barriers to public acceptance of wastewater reuse -with its ultimate culmination in direct reuse for drinking. I pose what could be a key question as to whether much of the public's frustration or ambivalence in its decision making process for accepting or rejecting water reuse (for various purposes including personal use) emanates from fundamental inaccuracies, misrepresentation, or oversimplification of what water 'is' and how it functions in the environment -just what exactly is the 'water cyc

  14. Arsenic Speciation in Groundwater: Role of Thioanions

    Science.gov (United States)

    The behavior of arsenic in groundwater environments is fundamentally linked to its speciation. Understanding arsenic speciation is important because chemical speciation impacts reactivity, bioavailability, toxicity, and transport and fate processes. In aerobic environments arsen...

  15. Probing the local environment of a superconductor-proximitized nanowire using single electron transistors

    Science.gov (United States)

    Pei, Fei; Cassidy, Maja; Plissard, Sebastien; Car, Diana; Bakkers, Erik; Kouwenhoven, Leo

    2014-03-01

    Majorana bound states are predicted to arise in semiconducting nanowires with strong spin-orbit coupling that are proximity-coupled to a s-wave superconductor and exposed to a magnetic field. Recent tunneling spectroscopy experiments have shown signatures of Majorana bound states through the existence of a peak in conductance that remains fixed to zero bias over a wide range in magnetic fields. Observation of the delocalized nature of these states remains an outstanding challenge. Here we present measurements of a InSb nanowire proximitized by a central superconducting contact. Normal metal leads allow tunneling spectroscopy from each end of the wire, while nearby single electron transistors provide simultaneous information on the local environment both within the proximitized wire and at each end.

  16. Electronic desalting for controlling the ionic environment in droplet-based biosensing platforms

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan, Vikhram Vilasur [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Dak, Piyush; Alam, Muhammad A., E-mail: rbashir@illinois.edu, E-mail: alam@purdue.edu [School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Reddy, Bobby; Duarte-Guevara, Carlos; Zhong, Yu [Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Salm, Eric [Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Fischer, Andrew [Abbott Laboratories, 1921 Hurd Drive, Dept. 8482 LC2 M/S 2-33, Irving, Texas 75038 (United States); Liu, Yi-Shao [Taiwan Semiconductor Manufacturing Company, Hsinchu 300-78, Taiwan (China); Bashir, Rashid, E-mail: rbashir@illinois.edu, E-mail: alam@purdue.edu [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

    2015-02-02

    The ability to control the ionic environment in saline waters and aqueous electrolytes is useful for desalination as well as electronic biosensing. We demonstrate a method of electronic desalting at micro-scale through on-chip micro electrodes. We show that, while desalting is limited in bulk solutions with unlimited availability of salts, significant desalting of ≥1 mM solutions can be achieved in sub-nanoliter volume droplets with diameters of ∼250 μm. Within these droplets, by using platinum-black microelectrodes and electrochemical surface treatments, we can enhance the electrode surface area to achieve >99% and 41% salt removal in 1 mM and 10 mM salt concentrations, respectively. Through self-consistent simulations and experimental measurements, we demonstrate that conventional double-layer theory over-predicts the desalting capacity and, hence, cannot be used to model systems that are mass limited or undergoing significant salt removal from the bulk. Our results will provide a better understanding of capacitive desalination, as well as a method for salt manipulation in high-throughput droplet-based microfluidic sensing platforms.

  17. Registering Nursing Interventions in Electronic Environments in Accordance with Nursing Process: an Example from Turkey

    Directory of Open Access Journals (Sweden)

    Fatma Ay

    2013-01-01

    Full Text Available Background: As being a professional occupation, development of nursing is affected by technological advancements in other fields. Aim of nursing is offering a safe, efficient and quality care. In general, lots of data, both quantitive and qualitative, is registered by nurses to the system of health records. Also usage of care plansadapted to computer environment has the benefits like eased risk management and analysis, standardization of given care, establishment of the communication between multi-discipliner care members, eased reading of documents.Aim: To determine the characteristics of electronic records to be able to employ nursing process successfully, a computer software which takes into account and reflects both the thinking process and condition of working places needs to be developed.Results: While computer and care plan usage have many positive ways, generally in Turkey it’s observed that usage of both are not at a desired level in nursing services. The computer software which is used to improve patient care quality must have qualities like being systematic, permanent, enabling diagnosises to be analyzed viadiscussions and to be systematically assessed, and giving guidance to nursing applications.Conclusion: Electronic patient registration system used by nurses should make time-saving possible, be easily used with easy menus, save all applications exactly, have warning and alarm systems, display necessary interventions at appropriate times, be a guide for patient care.

  18. Copper Environment in Artificial Metalloproteins Probed by Electron Paramagnetic Resonance Spectroscopy.

    Science.gov (United States)

    Flores, Marco; Olson, Tien L; Wang, Dong; Edwardraja, Selvakumar; Shinde, Sandip; Williams, JoAnn C; Ghirlanda, Giovanna; Allen, James P

    2015-10-29

    The design of binding sites for divalent metals in artificial proteins is a productive platform for examining the characteristics of metal-ligand interactions. In this report, we investigate the spectroscopic properties of small peptides and four-helix bundles that bind Cu(II). Three small peptides, consisting of 15 amino acid residues, were designed to have two arms, each containing a metal-binding site comprised of different combinations of imidazole and carboxylate side chains. Two four-helix bundles each had a binding site for a central dinuclear metal cofactor, with one design incorporating additional potential metal ligands at two identical sites. The small peptides displayed pH-dependent, metal-induced changes in the circular dichroism spectra, consistent with large changes in the secondary structure upon metal binding, while the spectra of the four-helix bundles showed a predominant α-helix content but only small structural changes upon metal binding. Electron paramagnetic resonance spectra were measured at X-band revealing classic Cu(II) axial patterns with hyperfine coupling peaks for the small peptides and four-helix bundles exhibiting a range of values that were related to the specific chemical natures of the ligands. The variety of electronic structures allow us to define the distinctive environment of each metal-binding site in these artificial systems, including the designed additional binding sites in one of the four-helix bundles.

  19. Energy band alignment and electronic states of amorphous carbon surfaces in vacuo and in aqueous environment

    Energy Technology Data Exchange (ETDEWEB)

    Caro, Miguel A., E-mail: mcaroba@gmail.com [Department of Electrical Engineering and Automation, Aalto University, Espoo (Finland); Department of Applied Physics, COMP Centre of Excellence in Computational Nanoscience, Aalto University, Espoo (Finland); Määttä, Jukka [Department of Chemistry, Aalto University, Espoo (Finland); Lopez-Acevedo, Olga [Department of Applied Physics, COMP Centre of Excellence in Computational Nanoscience, Aalto University, Espoo (Finland); Laurila, Tomi [Department of Electrical Engineering and Automation, Aalto University, Espoo (Finland)

    2015-01-21

    In this paper, we obtain the energy band positions of amorphous carbon (a–C) surfaces in vacuum and in aqueous environment. The calculations are performed using a combination of (i) classical molecular dynamics (MD), (ii) Kohn-Sham density functional theory with the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional, and (iii) the screened-exchange hybrid functional of Heyd, Scuseria, and Ernzerhof (HSE). PBE allows an accurate generation of a-C and the evaluation of the local electrostatic potential in the a-C/water system, HSE yields an improved description of energetic positions which is critical in this case, and classical MD enables a computationally affordable description of water. Our explicit calculation shows that, both in vacuo and in aqueous environment, the a-C electronic states available in the region comprised between the H{sub 2}/H{sub 2}O and O{sub 2}/H{sub 2}O levels of water correspond to both occupied and unoccupied states within the a-C pseudogap region. These are localized states associated to sp{sup 2} sites in a-C. The band realignment induces a shift of approximately 300 meV of the a-C energy band positions with respect to the redox levels of water.

  20. Tehran Groundwater Chemical Pollution

    Directory of Open Access Journals (Sweden)

    M- Shariatpanahi

    1990-06-01

    Full Text Available Seventy eight wells water sample of Tehran plain were examined to determine r its groundwaters chemical pollution. Tehran s groundwaters are slightly acidic and their total dissolved solids are high and are in the hard water category."nThe nitrate concentration of wells water of west region is less than per¬missible level of W.H.O. standard, whereas, the nitrate concentration of some of the other regions wells exceed W.H.O. standard which is indication of pollution"nwith municipal wastewaters. The concentration of toxic elements Cr, Cd, As, Hg and"ni Pb of some of the west, east and south regions wells of Tehran is more than per¬missible level of W.H.O. standard, whereas, the concentration of Cu, Zn,Mn and detergents is below W.H.O. standard."n1"nIn general, the amount of dissolved materials of Tehran s groundwaters and also"ni the potential of their contamination with nitrate is increased as Tehran s ground-"nwaters move further to the south, and even though, Tehran s groundwaters contamination with toxic elements is limited to the industrial west district, industrial-residential east and south districts, but»with regard to the disposal methods of"nt municipal and industrial wastewaters, if Tehran s groundwaters pollution continues,"nlocal contamination of groundwaters is likely to spread. So that finally their quality changes in such a way that this water source may become unfit for most domestic, industrial and agricultural uses. This survey shows the necessity of collection and treatment of Tehran s wastewaters and Prevention of the disposal of untreated wastewaters into the environment.

  1. Reliability of High I/O High Density CCGA Interconnect Electronic Packages under Extreme Thermal Environment

    Science.gov (United States)

    Ramesham, Rajeshuni

    2012-01-01

    This paper provides the experimental test results of advanced CCGA packages tested in extreme temperature thermal environments. Standard optical inspection and x-ray non-destructive inspection tools were used to assess the reliability of high density CCGA packages for deep space extreme temperature missions. Ceramic column grid array (CCGA) packages have been increasing in use based on their advantages such as high interconnect density, very good thermal and electrical performances, compatibility with standard surface-mount packaging assembly processes, and so on. CCGA packages are used in space applications such as in logic and microprocessor functions, telecommunications, payload electronics, and flight avionics. As these packages tend to have less solder joint strain relief than leaded packages or more strain relief over lead-less chip carrier packages, the reliability of CCGA packages is very important for short-term and long-term deep space missions. We have employed high density CCGA 1152 and 1272 daisy chained electronic packages in this preliminary reliability study. Each package is divided into several daisy-chained sections. The physical dimensions of CCGA1152 package is 35 mm x 35 mm with a 34 x 34 array of columns with a 1 mm pitch. The dimension of the CCGA1272 package is 37.5 mm x 37.5 mm with a 36 x 36 array with a 1 mm pitch. The columns are made up of 80% Pb/20%Sn material. CCGA interconnect electronic package printed wiring polyimide boards have been assembled and inspected using non-destructive x-ray imaging techniques. The assembled CCGA boards were subjected to extreme temperature thermal atmospheric cycling to assess their reliability for future deep space missions. The resistance of daisy-chained interconnect sections were monitored continuously during thermal cycling. This paper provides the experimental test results of advanced CCGA packages tested in extreme temperature thermal environments. Standard optical inspection and x-ray non

  2. Reliability of High I/O High Density CCGA Interconnect Electronic Packages under Extreme Thermal Environment

    Science.gov (United States)

    Ramesham, Rajeshuni

    2012-01-01

    This paper provides the experimental test results of advanced CCGA packages tested in extreme temperature thermal environments. Standard optical inspection and x-ray non-destructive inspection tools were used to assess the reliability of high density CCGA packages for deep space extreme temperature missions. Ceramic column grid array (CCGA) packages have been increasing in use based on their advantages such as high interconnect density, very good thermal and electrical performances, compatibility with standard surface-mount packaging assembly processes, and so on. CCGA packages are used in space applications such as in logic and microprocessor functions, telecommunications, payload electronics, and flight avionics. As these packages tend to have less solder joint strain relief than leaded packages or more strain relief over lead-less chip carrier packages, the reliability of CCGA packages is very important for short-term and long-term deep space missions. We have employed high density CCGA 1152 and 1272 daisy chained electronic packages in this preliminary reliability study. Each package is divided into several daisy-chained sections. The physical dimensions of CCGA1152 package is 35 mm x 35 mm with a 34 x 34 array of columns with a 1 mm pitch. The dimension of the CCGA1272 package is 37.5 mm x 37.5 mm with a 36 x 36 array with a 1 mm pitch. The columns are made up of 80% Pb/20%Sn material. CCGA interconnect electronic package printed wiring polyimide boards have been assembled and inspected using non-destructive x-ray imaging techniques. The assembled CCGA boards were subjected to extreme temperature thermal atmospheric cycling to assess their reliability for future deep space missions. The resistance of daisy-chained interconnect sections were monitored continuously during thermal cycling. This paper provides the experimental test results of advanced CCGA packages tested in extreme temperature thermal environments. Standard optical inspection and x-ray non

  3. groundwater contribution to crop water requirement groundwater ...

    African Journals Online (AJOL)

    eobe

    Keywords: Groundwater, water table, capillary rise, soil type, waterleaf, ... GROUNDWATER CONTRIBUTION TO WATERLEAF (TALINUM TRIANGULARE) IN OXISOLS, I. J. ... Nutritionally, ... information to facilitate increased crop production,.

  4. The use of Kriging Techniques with in GIS Environment to Investigate Groundwater Quality in the Amman-Zarqa Basin/Jordan

    Directory of Open Access Journals (Sweden)

    Atef Al-Mashagbah

    2012-02-01

    Full Text Available The Kriging techniques are called the best linear unbiased estimator since it tries to have a mean residual error equal to zero. It aims to minimizing the variance of the errors and hence is a strong advantage over other estimation methods like inverse distance weighting or moving average. In this study, the ordinary kriging techniques were used to estimate groundwater quality parameters (Ca2+, Mg2+, Na+, K+, Cl- and NO3-. It was found that the spatial interpolation of groundwater quality of the study area poses various problems due to the complex impact of cultivation and urbanization systems of the study area. Testing of various methods and parameters, by comparing and ranking their cross-correlation errors, show that ordinary kriging method using the different semivariogram models provides the overall good results. Also, most of the groundwater quality parameters have moderate spatial structure except NO3 and Ca that have a strong spatial structure.

  5. A Motor Drive Electronics Assembly for Mars Curiosity Rover: An Example of Assembly Qualification for Extreme Environments

    Science.gov (United States)

    Kolawa, Elizabeth; Chen, Yuan; Mojarradi, Mohammad M.; Weber, Carissa Tudryn; Hunter, Don J.

    2013-01-01

    This paper describes the technology development and infusion of a motor drive electronics assembly for Mars Curiosity Rover under space extreme environments. The technology evaluation and qualification as well as space qualification of the assembly are detailed and summarized. Because of the uncertainty of the technologies operating under the extreme space environments and that a high level reliability was required for this assembly application, both component and assembly board level qualifications were performed.

  6. Calendar Year 2016 Annual Groundwater Monitoring Report.

    Energy Technology Data Exchange (ETDEWEB)

    Copland, John R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jackson, Timmie Okchumpulla [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Li, Jun [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mitchell, Michael Marquand [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Skelly, Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-06-01

    Sandia National Laboratories, New Mexico (SNL/NM) is a government-owned/contractoroperated laboratory. National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., manages and operates SNL/NM for the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA). The DOE/NNSA Sandia Field Office administers the contract and oversees contractor operations at the site. Two types of groundwater surveillance monitoring are conducted at SNL/NM: (1) on a site-wide basis as part of the SNL/NM Long-Term Stewardship (LTS) Program’s Groundwater Monitoring Program (GMP) Groundwater Surveillance Task and (2) on a site-specific groundwater monitoring at LTS/Environmental Restoration (ER) Operations sites with ongoing groundwater investigations. This Annual Groundwater Monitoring Report summarizes data collected during groundwater monitoring events conducted at GMP locations and at the following SNL/NM sites through December 31, 2016: Burn Site Groundwater Area of Concern (AOC); Chemical Waste Landfill; Mixed Waste Landfill; Technical Area-V Groundwater AOC; and the Tijeras Arroyo Groundwater AOC. Environmental monitoring and surveillance programs are required by the New Mexico Environment Department (NMED) and DOE Order 436.1, Departmental Sustainability, and DOE Order 231.1B, Environment, Safety, and Health Reporting.

  7. Pedagogical Management of Learning Activities of Students in the Electronic Educational Environment of the University: A Differentiated Approach

    Science.gov (United States)

    Toktarova, Vera Ivanovna

    2015-01-01

    The present study considers issues related to the planning and implementation of the system of pedagogical management of learning activities of students in the context of modern electronic educational environment of the higher education institution. As a methodological basis considered a differentiated approach based on flexible individual…

  8. Complex role of secondary electron emissions in dust grain charging in space environments: measurements on Apollo 11 & 17 dust grains

    Science.gov (United States)

    Abbas, Mian; Tankosic, Dragana; Spann, James; Leclair, Andre C.

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, by electron/ion collisions, and sec-ondary electron emissions. Knowledge of the dust grain charges and equilibrium potentials is important for understanding of a variety of physical and dynamical processes in the interstel-lar medium (ISM), and heliospheric, interplanetary, planetary, and lunar environments. The high vacuum environment on the lunar surface leads to some unusual physical and dynam-ical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. It has been well recognized that the charging properties of individual micron/submicron size dust grains are expected to be substantially different from the corresponding values for bulk materials and theoretical models. In this paper we present experimental results on charging of individual dust grains selected from Apollo 11 and Apollo 17 dust samples by exposing them to mono-energetic electron beams in the 10-400 eV energy range. The charging rates of positively and negatively charged particles of 0.2 to 13 µm diam-eters are discussed in terms of the secondary electron emission (SEE) process, which is found to be a complex charging process at electron energies as low as 10-25 eV, with strong parti-cle size dependence. The measurements indicate substantial differences between dust charging properties of individual small size dust grains and of bulk materials.

  9. The dissipation of field emitting carbon nanotubes in an oxygen environment as revealed by in situ transmission electron microscopy.

    Science.gov (United States)

    Koh, Ai Leen; Gidcumb, Emily; Zhou, Otto; Sinclair, Robert

    2016-09-15

    In this work, we report the first direct experimental observations of carbon nanotubes (CNT) field emitting in an oxygen environment, using aberration-corrected environmental transmission electron microscopy in combination with an electrical biasing specimen holder under low-dose, field-free imaging conditions. Our studies show that while the CNTs remain stable during high vacuum field emission, they experience abrupt decreases in length, also termed "burn-back", when field-emitting in an oxygen environment at around 30 Pa pressure. Furthermore, we perform correlative field-free and aberration-corrected, high-resolution transmission electron microscopy imaging to understand how the structure of the CNTs - particularly the opening of the nanotube caps - is influenced by its gas environment during field emission. This work provides significant insight into the mechanism of carbon nanotube behavior under non-ideal field emission conditions.

  10. Electron plasma environment at comet Grigg-Skjellerup: General observations and comparison with the environment at comet Halley

    Science.gov (United States)

    Reme, H.; Mazelle, C.; Sauvaud, J. A.; D'Uston, C.; Froment, F.; Lin, R. P.; Anderson, K. A.; Carlson, C. W.; Larson, D. E.; Korth, A.

    1993-01-01

    The three-dimensional electron spectrometer of the Reme plasma analyzer-complete positive ion, electron and ram negative ion measurements near comet Halley (RPA-COPERNIC) experiment aboard the Giotto spacecraft, although damaged during the comet Halley encounter in March 1986, has provided very new results during the encounter on July 10, 1992, with the weakly active comet Grigg-Skjellerup (G-S). The main characteristic features of the highly structured interaction region extending from approximately 26,500 km inbound to approximately 37,200 km outbound are presented. These results are compared to the results obtained by the same instrument during the Giotto comet Halley fly-by. Despite the large difference in the size of the interaction regions (approximately 60,000 km for G-S, approximately 2000,000 km for Halley) due to 2 orders of magnitude difference in cometary neutral gas production rate, there are striking similarities in the solar wind interactions with the two comets.

  11. Remedies proposed for China's groundwater problems

    Science.gov (United States)

    Loaiciga, Hugo A.

    Groundwater experts and hydrologists from China and 10 other nations recently gathered in Beijing to exchange state-of-the-art scientific and technological knowledge on groundwater hydrology, modeling, remediation, and management. The participants also reviewed groundwater environmental conditions in China, identified key problems, and made recommendations to help guide the nation's groundwater policy.The Regional Workshop on Ground Water Contamination, held from July 31 to August 4, 1995, was the fifth of a series of regional workshops sponsored by the Scientific Committee on Problems of the Environment of the United Nations Environmental Program. Earlier workshops were held in Thailand (1991), Costa Rica (1993), the Czech Republic (1994), and Australia (1994).

  12. Life in the absence of oxygen: alterative electron acceptors for anaerobic microorganisms in a petroleum environment

    NARCIS (Netherlands)

    Balk, M.

    2007-01-01

    Anaerobic microorganisms derive energy by transferring electrons from an external source or donor to an external electron sink or terminal acceptor and often have the capacity to reduce 2 or more terminal electron acceptors. The well-known type of microbial respiration, in which oxygen serves as an

  13. Archetype-based data warehouse environment to enable the reuse of electronic health record data.

    Science.gov (United States)

    Marco-Ruiz, Luis; Moner, David; Maldonado, José A; Kolstrup, Nils; Bellika, Johan G

    2015-09-01

    The reuse of data captured during health care delivery is essential to satisfy the demands of clinical research and clinical decision support systems. A main barrier for the reuse is the existence of legacy formats of data and the high granularity of it when stored in an electronic health record (EHR) system. Thus, we need mechanisms to standardize, aggregate, and query data concealed in the EHRs, to allow their reuse whenever they are needed. To create a data warehouse infrastructure using archetype-based technologies, standards and query languages to enable the interoperability needed for data reuse. The work presented makes use of best of breed archetype-based data transformation and storage technologies to create a workflow for the modeling, extraction, transformation and load of EHR proprietary data into standardized data repositories. We converted legacy data and performed patient-centered aggregations via archetype-based transformations. Later, specific purpose aggregations were performed at a query level for particular use cases. Laboratory test results of a population of 230,000 patients belonging to Troms and Finnmark counties in Norway requested between January 2013 and November 2014 have been standardized. Test records normalization has been performed by defining transformation and aggregation functions between the laboratory records and an archetype. These mappings were used to automatically generate open EHR compliant data. These data were loaded into an archetype-based data warehouse. Once loaded, we defined indicators linked to the data in the warehouse to monitor test activity of Salmonella and Pertussis using the archetype query language. Archetype-based standards and technologies can be used to create a data warehouse environment that enables data from EHR systems to be reused in clinical research and decision support systems. With this approach, existing EHR data becomes available in a standardized and interoperable format, thus opening a world

  14. Groundwater Waters

    Directory of Open Access Journals (Sweden)

    Ramón Llamas

    1999-10-01

    Full Text Available The groundwaters released through springs constituted a basic element for the survival and progressive development of human beings. Man came to learn how to take better advantage of these waters by digging wells, irrigation channels, and galleries. Nevertheless, these activities do not require cooperation nor the collective agreement of relatively large groups of people, as in the case of creating the necessary structures to take advantage of the resources of surfacewaters. The construction and operation of these structures was a powerful factor in the birth of an urban or civil society – the designated water civilizations. The difference between people taking advantage of groundwater, quasi-individually, and those of surface water, where people work in a group, has continued to the present day. Whereas earlier, this difference did not bring about any special problems, the technological advances of this century, especially theturbine pump, have led to a spectacular increase in the use of roundwater. This advance has significantly contributed to reducing hunger in the world and has provided potable water in developing countries. However, the almost generalized lack of planning and control in the exploitation of these groundwaters reflects that they are little or badly understood by the managers of water policy in almost every country. As such, problems have occurred which have often become exaggerated, giving rise to water-myths. These problems, though, should be addressed if the aim is the sustainable usage of surface water as well as groundwater. To counter any misconceptions and to seek solutions to the problems, distinct plans of action can be highlighted: educating the public; fomenting a system of participative management and decisive support for the communities of users of subterranean waters; integrating a sufficient number of experts in hydrology in the various water management organizations;and assuring transparency of the data on

  15. Innovative Methods for Integrating Knowledge for Long-Term Monitoring of Contaminated Groundwater Sites: Understanding Microorganism Communities and their Associated Hydrochemical Environment

    Science.gov (United States)

    Mouser, P. J.; Rizzo, D. M.; Druschel, G.; O'Grady, P.; Stevens, L.

    2005-12-01

    This interdisciplinary study integrates hydrochemical and genome-based data to estimate the redox processes occurring at long-term monitoring sites. Groundwater samples have been collected from a well-characterized landfill-leachate contaminated aquifer in northeastern New York. Primers from the 16S rDNA gene were used to amplify Bacteria and Archaea in groundwater taken from monitoring wells located in clean, fringe, and contaminated locations within the aquifer. PCR-amplified rDNA were digested with restriction enzymes to evaluate terminal restriction fragment length polymorphism (T-RFLP) community profiles. The rDNA was cloned, sequenced, and partial sequences were matched against known organisms using the NCBI Blast database. Phylogenetic trees and bootstrapping were used to identify classifications of organisms and compare the communities from clean, fringe, and contaminated locations. We used Artificial Neural Network (ANN) models to incorporate microbial data with hydrochemical information for improving our understanding of subsurface processes.

  16. 40 CFR 258.51 - Ground-water monitoring systems.

    Science.gov (United States)

    2010-07-01

    ... preclude installation of ground-water monitoring wells at the relevant point of compliance at existing... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water monitoring systems. 258... CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51...

  17. [Construction of groundwater contamination prevention mapping system].

    Science.gov (United States)

    Wang, Jun-Jie; He, Jiang-Tao; Lu, Yan; Liu, Li-Ya; Zhang, Xiao-Liang

    2012-09-01

    Groundwater contamination prevention mapping is an important component of groundwater contamination geological survey and assessment work, which could provide the basis for making and implementing groundwater contamination prevention planning. A groundwater contamination prevention mapping system was constructed in view of the synthetic consideration on nature perspective derived from groundwater contamination sources and aquifer itself, social-economic perspective, policy perspective derived from outside. During the system construction process, analytic hierarchy process and relevant overlaying principles were used to couple groundwater contamination risk assessment, groundwater value as well as wellhead protection area zoning. Data processing and visualization of mapping results were achieved in the GIS environment. The research on groundwater contamination prevention mapping in Beijing Plain indicated that the final groundwater prevention map was in accordance with the actual conditions and well reflected the priorities of groundwater prevention, which could play a guidance role in designing and implementing further practical prevention and supervision measures. Besides, because of the dynamical properties of the system components, it was suggested to analyze the update frequency of the mapping.

  18. Monitoring groundwater drought with GRACE data assimilation

    Science.gov (United States)

    Li, B.; Rodell, M.; Beaudoing, H. K.; Getirana, A.; Zaitchik, B. F.

    2015-12-01

    Groundwater drought is a distinct class of drought, not a sub-class of meteorological, agricultural and hydrological drought and has profound impacts on natural environments and societies. Due to a deficiency of in situ measurements, we developed a groundwater drought indicator using groundwater change estimates derived by assimilating GRACE derived terrestrial water storage (TWS) anomalies into the NASA Catchment land surface model. Data assimilation enables spatial and temporal downscaling of coarse GRACE TWS observations (monthly and ~150,000 km2 effective spatial resolution) and extrapolation to near-real time. In this talk, we will present our latest progress on using GRACE satellite data for groundwater drought monitoring in the U.S. and globally. Characteristics of this groundwater drought indicator will be discussed, including its relationship with other types of drought and how they are influenced by model physics and climate conditions. Results are evaluated using in situ groundwater observations.

  19. Groundwater and security

    NARCIS (Netherlands)

    Conti, K.I.; Kukurić, N.; Gupta, J.; Pahl-Wostl, C.; Bhaduri, A.; Gupta, J.

    2016-01-01

    Humans abstract two hundred times more groundwater than oil, annually. Ironically, the role of groundwater in water management and supply is underappreciated, partially due to its invisibility. By conducting a literature survey and investigating groundwater information databases, this chapter answer

  20. Complex influence of space environment on materials and electronic devices in the conditions of microgravity

    Science.gov (United States)

    Musabayev, T.; Zhantayev, Zh.; Grichshenko, V.

    2016-09-01

    The paper presents a new physical model describing the processes in materials and electronic devices under the influence of cosmic rays in microgravity. The model identifies specific features of formation of the area of radiation defects (ARD) in the electronic materials in microgravity. The mechanism of interaction between the ARD and memory modules in microgravity causing malfunction and failure of onboard electronics is considered. The results of failure of memory modules under real conditions are presented.

  1. The SIRENE facility - an improved method for simulating the charge of dielectrics in a charging electron environment

    Science.gov (United States)

    Dirassen, B.; Levy, L.; Reulet, R.; Payan, D.

    2003-09-01

    Due to their dielectric nature and under the effect of the different forms of radiation encountered in space, dielectrics accumulate electrical charges up to the point where electrostatic discharges may occur. To prevent and avoid harmful interference due to discharges, their behaviour under irradiation must therefore be investigated in the laboratory before they are used in space applications. A current and widely used practice is to submit the tested materials to the bombardment of monoenergetic electron beams. Such a practice ignores the presence in space of a spectrum of electrons with energies reaching several MeV, and leads solely to surface charging and surface potentials generally higher than those really induced in space. The new approach used by "SIRENE" is to build an electron source as similar as possible to the one existing in orbit. This paper describes the SIRENE facility, which was developed for simulating the spatial geo-stationary environment during great geomagnetic activity. The range of available electrons goes from 10 to 400 keV. From a monoenergetic electron beam of 400 keV and thanks to a complex diffusion foil (made of several foils of different thicknesses and surface areas) the quantity of electrons of each energy level present in this particular environment is reproduced. However, it is always possible to work at lower energy levels in the monoenergetic range, for instance to simulate the inverted gradient mode. This paper provides information on the spectrum used for testing materials in the geo-stationary environment, and on the potential for adapting it to other orbits. It also gives the first results demonstrating the interest of this new approach. It also mentions the new instruments used to measure the surface potential as well as the space charge through the complete thickness of the material.

  2. Simulating groundwater-induced sewer flooding

    Science.gov (United States)

    Mijic, A.; Mansour, M.; Stanic, M.; Jackson, C. R.

    2016-12-01

    During the last decade, Chalk catchments of southern England experienced severe groundwater flooding. High groundwater levels resulted in the groundwater ingress into the sewer network that led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. In response to these events the water and sewerage company Thames Water Utilities Ltd (TWUL) had to allocate significant funds to mitigate the impacts. It was estimated that approximately £19m was spent responding to the extreme wet weather of 2013-14, along with the use of a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. This work presents the analysis of the risk of groundwater-induced sewer flooding within the Chalk catchment of the River Lambourn, Berkshire. A spatially distributed groundwater model was used to assess historic groundwater flood risk and the potential impacts of changes in future climate. We then linked this model to an urban groundwater model to enable us to simulate groundwater-sewer interaction in detail. The modelling setup was used to identify relationships between infiltration into sewers and groundwater levels at specific points on TWUL's sewer network, and to estimate historic and future groundwater flood risk, and how this varies across the catchment. The study showed the significance of understanding the impact of groundwater on the urban water systems, and producing information that can inform a water company's response to groundwater flood risk, their decision making process and their asset management planning. However, the knowledge gained through integrated modelling of groundwater-sewer interactions has highlighted limitations of existing approaches for the simulation of these coupled systems. We conclude this work with number of recommendations about how to improve such hydrological/sewer analysis.

  3. Electron attachment properties of c-C4F8O in different environments

    Science.gov (United States)

    Chachereau, A.; Fedor, J.; Janečková, R.; Kočišek, J.; Rabie, M.; Franck, C. M.

    2016-09-01

    The electron attachment properties of octafluorotetrahydrofuran (c-C4F8O) are investigated using two complementary experimental setups. The attachment and ionization cross sections of c-C4F8O are measured using an electron beam experiment. The effective ionization rate coefficient, electron drift velocity and electron diffusion coefficient in c-C4F8O diluted to concentrations lower than 0.6% in the buffer gases N2, CO2 and Ar, are measured using a pulsed Townsend experiment. A kinetic model is proposed, which combines the results of the two experiments.

  4. AUTOMATING GROUNDWATER SAMPLING AT HANFORD

    Energy Technology Data Exchange (ETDEWEB)

    CONNELL CW; HILDEBRAND RD; CONLEY SF; CUNNINGHAM DE

    2009-01-16

    Until this past October, Fluor Hanford managed Hanford's integrated groundwater program for the U.S. Department of Energy (DOE). With the new contract awards at the Site, however, the CH2M HILL Plateau Remediation Company (CHPRC) has assumed responsibility for the groundwater-monitoring programs at the 586-square-mile reservation in southeastern Washington State. These programs are regulated by the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response Compensation and Liability Act (CERCLA). The purpose of monitoring is to track existing groundwater contamination from past practices, as well as other potential contamination that might originate from RCRA treatment, storage, and disposal (TSD) facilities. An integral part of the groundwater-monitoring program involves taking samples of the groundwater and measuring the water levels in wells scattered across the site. More than 1,200 wells are sampled each year. Historically, field personnel or 'samplers' have been issued pre-printed forms that have information about the well(s) for a particular sampling evolution. This information is taken from the Hanford Well Information System (HWIS) and the Hanford Environmental Information System (HEIS)--official electronic databases. The samplers used these hardcopy forms to document the groundwater samples and well water-levels. After recording the entries in the field, the samplers turned the forms in at the end of the day and the collected information was posted onto a spreadsheet that was then printed and included in a log book. The log book was then used to make manual entries of the new information into the software application(s) for the HEIS and HWIS databases. This is a pilot project for automating this tedious process by providing an electronic tool for automating water-level measurements and groundwater field-sampling activities. The automation will eliminate the manual forms and associated data entry, improve the

  5. Degrees of secrecy in an open environment. The case of electronic theses and dissertations

    Directory of Open Access Journals (Sweden)

    Joachim SCHÖPFE

    2013-12-01

    Full Text Available The open access (OA principle requires that scientific information be made widely and readily available to society. Defined in 2003 as a “comprehensive source of human knowledge and cultural heritage that has been approved by the scientific community”, open access implies that content be openly accessible and this needs the active commitment of each and every individual producer of scientific knowledge. Today, the success of the open access initiative cannot be denied. Yet, in spite of the growing success of the open access initiative, a significant part of scientific and technical information remains unavailable on the web or circulates with restrictions. Even in institutional repositories (IR created to provide access to the scientific output of an academic institution and central vector of the so-called green road to open access, more or less important sectors of the scientific production are missing. This is because of lack of awareness, embargo, deposit of metadata without full text, confidential content etc. This problem concerns in particular electronic theses and dissertations (ETDs that are disseminated with different statuses – some are freely available, others are under embargo, confidential, restricted to campus access (encrypted or not or not available at all. While other papers may be available through alternative channels (journals, monographs etc., ETDs most often are not. Our paper describes a new and unexpected effect of the development of digital libraries and open access, as a paradoxical practice of hiding information from the scientific community and society, partly while sharing it with a restricted population (campus. We try to explain these different shades of grey literature in terms of different degrees of secrecy related to intellectual property, legitimate interests, expected exploitation and trade secrets, and suggest some ways of increasing availability of ETDs in an open environment (inter-lending loan and

  6. An Analysis of Electronic Media to Prepare Children for Safe and Ethical Practices in Digital Environments

    Science.gov (United States)

    Berson, Ilene R.; Berson, Michael J.; Desai, Shreya; Falls, Donald; Fenaughty, John

    2008-01-01

    A range of electronic resources, including video-based instruction, are used to promote cybersafety to young people at school. This evaluation analyzed seven distinct programs that use electronic media in Internet safety initiatives in schools. The findings highlight emerging evidence on successful approaches to engage children in assessing risky…

  7. Roles of chemical metrology in electronics industry and associated environment in Korea: a tutorial.

    Science.gov (United States)

    Kang, Namgoo; Kim, Kyung Joong; Kim, Jin Seog; Lee, Joung Hae

    2015-03-01

    Chemical metrology is gaining importance in electronics industry that manufactures semiconductors, electronic displays, and microelectronics. Extensive and growing needs from this industry have raised the significance of accurate measurements of the amount of substances and material properties. For the first time, this paper presents information on how chemical metrology is being applied to meet a variety of needs in the aspects of quality control of electronics products and environmental regulations closely associated with electronics industry. For a better understanding of the roles of the chemical metrology within electronics industry, the recent research activities and results in chemical metrology are presented using typical examples in Korea where electronic industry is leading a national economy. Particular attention is paid to the applications of chemical metrology for advancing emerging electronics technology developments. Such examples are a novel technique for the accurate quantification of gas composition at nano-liter levels within a MEMS package, the surface chemical analysis of a semiconductor device. Typical metrological tools are also presented for the development of certified reference materials for fluorinated greenhouse gases and proficiency testing schemes for heavy metals and chlorinated toxic gas in order to cope properly with environmental issues within electronics industry. In addition, a recent technique is presented for the accurate measurement of the destruction and removal efficiency of a typical greenhouse gas scrubber.

  8. Quantitative and qualitative analysis of groundwater in aguanaval and chupaderos aquifers (Mexico)

    Science.gov (United States)

    Adequate regional groundwater assessment studies are essential for the correct groundwater management by policy/decision makers; increased use of groundwater resources and drought have led to concern about the future availability of groundwater to meet domestic, agricultural, industrial, and environ...

  9. Professional DOC (PDOC): a software environment for authoring and consulting of electronic documentation. INTERACTIVE DIAGNOSIS and THERAPY: a medical application.

    OpenAIRE

    Abbolito, A.; Camici, A.; Spampinato, A.

    1992-01-01

    Professional DOC (PDOC) is a software environment for electronic documentation authoring and consulting based on the Hypermedia technology. It allows to manage different kinds of information (pictures, sounds, texts, graphics, video) organized according to hyperstructures. The user-friendliness and effectiveness of its man-machine interface, and its availability on the most common hardware platforms makes it a suitable product for a very broad category of users. INTERACTIVE DIAGNOSIS AND THER...

  10. An Automated Electronic Tongue for In-Situ Quick Monitoring of Trace Heavy Metals in Water Environment

    Science.gov (United States)

    Cai, Wei; Li, Yi; Gao, Xiaoming; Guo, Hongsun; Zhao, Huixin; Wang, Ping

    2009-05-01

    An automated electronic tongue instrumentation has been developed for in-situ concentration determination of trace heavy metals in water environment. The electronic tongue contains two main parts. The sensor part consists of a silicon-based Hg-coated Au microelectrodes array (MEA) for the detection of Zn(II), Cd(II), Pb(II) and Cu(II) and a multiple light-addressable potentiometric sensor (MLAPS) for the detection of Fe(III) and Cr(VI). The control part employs pumps, valves and tubes to enable the pick-up and pretreatment of aqueous sample. The electronic tongue realized detection of the six metals mentioned above at part-per-billion (ppb) level without manual operation. This instrumentation will have wide application in quick monitoring and prediction the heavy metal pollution in lakes and oceans.

  11. Monolithically integrated AlN/GaN electronics for harsh environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Recently, resonant-tunneling-diode (RTD) based circuits employing monolithically-integrated RTD on high electron mobility (HEMT) structures have been developed in a...

  12. Demonstration of a Passive Thermal Management System for Cooling Electronics in Extreme Environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Extended operation of exploratory systems on the surface of planets like Venus, means that techniques to cool system electronics to essentially room temperature...

  13. Availability, Access, Authenticity, and Persistence: Creating the Environment for Permanent Public Access to Electronic Government Information.

    Science.gov (United States)

    Barnum, George

    2002-01-01

    Discusses efforts by the Federal Depository Library Program to make information accessible more or mostly by electronic means. Topics include Web-based locator tools; collection development; digital archives; bibliographic metadata; and access tools and user interfaces. (Author/LRW)

  14. A Review of NASA's Radiation-Hardened Electronics for Space Environments Project

    Science.gov (United States)

    Keys, Andrew S.; Adams, James H.; Patrick, Marshall C.; Johnson, Michael A.; Cressler, John D.

    2008-01-01

    NASA's Radiation Hardened Electronics for Space Exploration (RHESE) project develops the advanced technologies required to produce radiation hardened electronics, processors, and devices in support of the requirements of NASA's Constellation program. Over the past year, multiple advancements have been made within each of the RHESE technology development tasks that will facilitate the success of the Constellation program elements. This paper provides a brief review of these advancements, discusses their application to Constellation projects, and addresses the plans for the coming year.

  15. Energetic Constraints on H-2-Dependent Terminal Electron Accepting Processes in Anoxic Environments

    DEFF Research Database (Denmark)

    Heimann, Axel Colin; Jakobsen, Rasmus; Blodau, C.

    2010-01-01

    Microbially mediated terminal electron accepting processes (TEAPs) to a large extent control the fate of redox reactive elements and associated reactions in anoxic soils, sediments, and aquifers. This review focuses on thermodynamic controls and regulation of H-2-dependent TEAPs, case studies...... illustrating this concept and the quantitative description of thermodynamic controls in modeling. Other electron transfer processes are considered where appropriate. The work reviewed shows that thermodynamics and microbial kinetics are connected near thermodynamic equilibrium. Free energy thresholds...

  16. 盐碱地下水环境中桩基混凝土耐腐蚀研究%Corrosion research on pile concrete in saline groundwater environments

    Institute of Scientific and Technical Information of China (English)

    丁建彤; 宁逢伟; 王奇

    2015-01-01

    Sulfur resistant cement and ordinary Portland cement used in pile concrete were compared and analysed for the differences of corrosion resistant ability in saline groundwater and sulfate solution with the same sulfate concentration.The differences between doped and non - doped sulfate resistant preservatives in pile concrete were inspected.The results indicate that sulfur resistant cement in both e-rosion compared with ordinary Portland cement behaved better sulfate resistance.Early contact with groundwater sulfur resistant cement compared with ordinary Portland cement had higher resistance to chloride ion intrusion capability.With the proliferation age prolonging, the advantages of sulfur resistant cement were lowed slowly and ultimately inferior to ordinary Portland cement.Compared with the situa-tion of non - doped,sulfate resistant ability of concrete with preservatives is higher in a single sulfate solution,while they are considerable in saline groundwater;concrete using preservatives had lower resistance to chloride ion intrusion capability than that situation of non -doped concrete.%对比分析了抗硫水泥和普硅水泥在盐碱地下水和硫酸盐溶液(同硫酸根浓度)中的差异,考察了掺与不掺抗硫酸盐防腐剂在两种侵蚀溶液中的区别。结果表明:抗硫水泥在两种侵蚀溶液中较普硅水泥具较好的抗硫酸盐侵蚀性能;抗硫水泥接触地下水初期较普硅水泥具较高的抗氯离子侵入能力,优势伴随扩散时间延长逐渐减弱最终不如普硅水泥。与不掺的情况相比,掺防腐剂混凝土在单一的硫酸盐溶液中抗硫酸盐侵蚀能力较强,地下水中区别不大;掺所试验防腐剂抗氯离子侵入能力不如50%掺合料的基准混凝土。

  17. Electronic health record meets digital library: a new environment for achieving an old goal.

    Science.gov (United States)

    Humphreys, B L

    2000-01-01

    Linking the electronic health record to the digital library is a Web-era reformulation of the long-standing informatics goal of seamless integration of automated clinical data and relevant knowledge-based information to support informed decisions. The spread of the Internet, the development of the World Wide Web, and converging format standards for electronic health data and digital publications make effective linking increasingly feasible. Some existing systems link electronic health data and knowledge-based information in limited settings or limited ways. Yet many challenging informatics research problems remain to be solved before flexible and seamless linking becomes a reality and before systems become capable of delivering the specific piece of information needed at the time and place a decision must be made. Connecting the electronic health record to the digital library also requires positive resolution of important policy issues, including health data privacy, government encouragement of high-speed communications, electronic intellectual property rights, and standards for health data and for digital libraries. Both the research problems and the policy issues should be important priorities for the field of medical informatics.

  18. Effects of electron irradiation in space environment on thermal and mechanical properties of carbon fiber/bismaleimide composite

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Qi, E-mail: yuqi1027@126.com [Liaoning Key Laboratory of Advanced Polymer Matrix Composites and Faculty of Aerospace Engineering, Shenyang Aerospace University, Shenyang 110136 (China); Chen, Ping, E-mail: chenping_898@126.com [Liaoning Key Laboratory of Advanced Polymer Matrix Composites and Faculty of Aerospace Engineering, Shenyang Aerospace University, Shenyang 110136 (China); State Key Laboratory of Fine Chemicals and School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China); Gao, Yu; Ma, Keming; Lu, Chun; Xiong, Xuhai [Liaoning Key Laboratory of Advanced Polymer Matrix Composites and Faculty of Aerospace Engineering, Shenyang Aerospace University, Shenyang 110136 (China)

    2014-10-01

    Highlights: •Electron irradiation decreased the storage modulus finally. •T{sub g} decreased first and then increased and finally decreased. •The thermal stability was reduced and then improved and finally decreased. •The changing trend of flexural strength and ILSS are consistent. -- Abstract: The effects of electron irradiation in simulated space environment on thermal and mechanical properties of high performance carbon fiber/bismaleimide composites were investigated. The dynamic mechanical properties of the composites exposed to different fluences of electron irradiation were evaluated by Dynamic mechanical analysis (DMA). Thermogravimetric analysis was applied to investigate the changes in thermal stability of the resin matrix after exposure to electron irradiation. The changes in mechanical properties of the composites were evaluated by flexural strength and interlaminar shear strength (ILSS). The results indicated that electron irradiation in high vacuum had an impact on thermal and mechanical properties of CF/BMI composites, which depends on irradiation fluence. At lower irradiation fluences less than 5 × 10{sup 15} cm{sup −2}, the dynamic storage modulus, cross-linking degree, thermal stability and mechanical properties that were determined by a competing effect between chain scission and cross-linking process, decreased firstly and then increased. While at higher fluences beyond 5 × 10{sup 15} cm{sup −2}, the chain scission process was dominant and thus led to the degradation in thermal and mechanical properties of the composites.

  19. Electronic Scholarly Journals: A Review of Technical Issues in Digital Environment

    Directory of Open Access Journals (Sweden)

    Golnessa Galyani Moghaddam

    2006-12-01

    Full Text Available Scholarly journals are known as the most important medium for scholarly communication since long time back. As technology transforms the flow of information and idea everywhere, it changes the nature of scholarly communications and publishing of scholarly journals as well. The electronic scholarly publishing rapidly produced an expectation, among researchers of the availability of articles at their desktop, rather than the previous scenario of visiting the library to read a print journal issue. There are lots of technological improvements in electronic journals publishing. The present paper looks at some of technical issues in electronic publishing such as DOI, DOI-X, CrossRef, Citation/Reference Linking, OpenURL, SFX and MetaLib which are being used in the World Wide Web.

  20. The near-surface electron radiation environment of Saturn's moon Mimas

    Science.gov (United States)

    Nordheim, Tom; Hand, Kevin P.; Paranicas, Christopher; Howett, Carly; Hendrix, Amanda R.; Jones, Geraint H.; Coates, Andrew

    2016-10-01

    Introduction: Saturn's inner mid-size moons are exposed to a number of external weathering processes, including charged particle bombardment and UV photolysis, as well as deposition of E ring grains and interplanetary dust. While optical remote sensing observations by several instruments onboard the Cassini spacecraft have revealed a number of weathering patterns across the surfaces of these moons, it is currently not entirely clear which external process is responsible for which observed weathering pattern. Here we focus on Saturn's moon Mimas and model the effect of energetic electron bombardment across its surface. Our results are discussed in the context of previously reported Cassini remote sensing observations of Mimas.Methods: To model the access of energetic electrons to different surface locations we used a guiding center, bounce-averaged approach which has previously been employed for the Jovian and Saturnian moons. The electron spectrum at the orbit of Mimas was implemented according to the fit functions provided by, which are based on averaged measurements from the Cassini Magnetospheric Imaging Instrument (MIMI) Low Energy Magnetospheric Measurement System (LEMMS) at a narrow corridor near the orbit of Mimas (~3.08 Rs) during the period 2004-2013. The interaction of electrons with the surface of Mimas was implemented using the PLANETOCOSMICS code, which is based on the Geant4 toolkit.Results: We predict a lens-shaped electron energy deposition pattern which extends down to ~cm depths at low latitudes near the center of the leading hemisphere. These results are consistent with previous remote sensing observations of a lens-shaped color anomaly [4] as well as a thermal inertia anomaly at this location. At the trailing hemisphere, we predict a similar lens-shaped electron energy deposition pattern, which to date has not been observed by the Cassini optical remote sensing instruments. We suggest that no corresponding lens-shaped weathering pattern has been

  1. Recharge sources and hydrogeochemical evolution of groundwater in semiarid and karstic environments: A field study in the Granada Basin (Southern Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Kohfahl, Claus [Freie Universitaet Berlin, Institute of Geological Sciences, Malteserstr. 74-100, D-12249 Berlin (Germany)], E-mail: kohfahl@zedat.fu-berlin.de; Sprenger, Christoph [Freie Universitaet Berlin, Institute of Geological Sciences, Malteserstr. 74-100, D-12249 Berlin (Germany); Herrera, Jose Benavente [Instituto del Agua de la Universidad de Granada, Ramon y Cajal, 4, 18071 Granada (Spain); Meyer, Hanno [Isotope Laboratory of the Alfred Wegener Institute for Polar and Marine Research, Research Unit Potsdam, Telegrafenberg A 43, 14473 Potsdam (Germany); Chacon, Franzisca Fernandez [Dpto. Hidrogeologia y Aguas Subterraneas, Instituto Geologico y Minero de Espana, Oficina de Proyectos, Urb. Alcazar del Genil 4, Edificio Zulema bajo, 18006 Granada (Spain); Pekdeger, Asaf [Freie Universitaet Berlin, Institute of Geological Sciences, Malteserstr. 74-100, D-12249 Berlin (Germany)

    2008-04-15

    The objective of this study is to refine the understanding of recharge processes in watersheds representative for karstic semiarid areas by means of stable isotope analysis and hydrogeochemistry. The study focuses on the Granada aquifer system which is located in an intramontane basin bounded by high mountain ranges providing elevation differences of almost 2900 m. These altitude gradients lead to important temperature and precipitation gradients and provide excellent conditions for the application of stable isotopes of water whose composition depends mainly on temperature. Samples of rain, snow, surface water and groundwater were collected at 154 locations for stable isotope studies ({delta}{sup 18}O, D) and, in the case of ground- and surface waters, also for major and minor ion analysis. Thirty-seven springs were sampled between 2 and 5 times from October 2004 to March 2005 along an altitudinal gradient from 552 masl in the Granada basin to 2156 masl in Sierra Nevada. Nine groundwater samples were taken from the discharge of operating wells in the Granada basin which are all located between 540 and 728 masl. The two main rivers were monitored every 2-3 weeks at three different altitudes. Rainfall being scarce during the sampling period, precipitation could only be sampled during four rainfall events. Calculated recharge altitudes of springs showed that source areas of mainly snowmelt recharge are generally located between 1600 and 2000 masl. The isotope compositions of spring water indicate water sources from the western Mediterranean as well as from the Atlantic without indicating a seasonal trend. The isotope pattern of the Quaternary aquifer reflects the spatial separation of different sources of recharge which occur mainly by bankfiltration of the main rivers. Isotopic signatures in the southeastern part of the aquifer indicate a considerable recharge contribution by subsurface flow discharged from the adjacent carbonate aquifer. No evaporation effects due

  2. Environment-sensitive fluorescent probe: a benzophosphole oxide with an electron-donating substituent.

    Science.gov (United States)

    Yamaguchi, Eriko; Wang, Chenguang; Fukazawa, Aiko; Taki, Masayasu; Sato, Yoshikatsu; Sasaki, Taeko; Ueda, Minako; Sasaki, Narie; Higashiyama, Tetsuya; Yamaguchi, Shigehiro

    2015-04-07

    Electron-donating aryl groups were attached to electron-accepting benzophosphole skeletons. Among several derivatives thus prepared, one benzophosphole oxide was particularly interesting, as it retained high fluorescence quantum yields even in polar and protic solvents. This phosphole-based compound exhibited a drastic color change of its fluorescence spectrum as a function of the solvent polarity, while the absorption spectra remained virtually unchanged. Capitalizing on these features, this phosphole-based compound was used to stain adipocytes, in which the polarity of subcellular compartments could then be discriminated on the basis of the color change of the fluorescence emission.

  3. Monitoring of biological odour filtration in closed environments with olfactometry and an electronic nose

    NARCIS (Netherlands)

    Willers, H.C.; Gijsel, de P.; Ogink, N.W.M.; Amico, D' A.; Martinelli, E.; Natale, Di C.; Ras, van N.; Waarde, van der J.

    2004-01-01

    Air treatment with a compact biological membrane filter, and air quality monitoring with an electronic nose were tested in the laboratory on air from a cage containing six mice. Additional analyses of air to and from the filter were performed using olfactometry and ammonia and hydrogen sulphide gas

  4. Shifts and Dips in Inelastic Electron Tunneling Spectra Due to the Tunnel Junction Environment.

    Science.gov (United States)

    1981-05-27

    biochemistry,7𔄂 9 10 1water polution , electron beam irradiation, UV irradiation 12and lubrication 2 . Particularly promising applications have...partially oxidized the strip in air at 200 0C to form the alumina insulating barrier. Prior to the catalyst metal evaporation we cleaned the slide in

  5. Advantages and Challenges of Teaching in an Electronic Environment: The Accommodate Model

    Science.gov (United States)

    Coyner, Sandy C.; McCann, Peggy L.

    2004-01-01

    The explosion of technology as a tool for teaching and learning has provided many opportunities for educators to participate in web-enhanced and web-based electronic classrooms. Further, distributed learning has provided learners with multiple access to course material in postsecondary education. While effective teaching strategies transfer to an…

  6. The Electronic Documentation Project in the NASA mission control center environment

    Science.gov (United States)

    Wang, Lui; Leigh, Albert

    1994-01-01

    NASA's space programs like many other technical programs of its magnitude is supported by a large volume of technical documents. These documents are not only diverse but also abundant. Management, maintenance, and retrieval of these documents is a challenging problem by itself; but, relating and cross-referencing this wealth of information when it is all on a medium of paper is an even greater challenge. The Electronic Documentation Project (EDP) is to provide an electronic system capable of developing, distributing and controlling changes for crew/ground controller procedures and related documents. There are two primary motives for the solution. The first motive is to reduce the cost of maintaining the current paper based method of operations by replacing paper documents with electronic information storage and retrieval. And, the other is to improve the efficiency and provide enhanced flexibility in document usage. Initially, the current paper based system will be faithfully reproduced in an electronic format to be used in the document viewing system. In addition, this metaphor will have hypertext extensions. Hypertext features support basic functions such as full text searches, key word searches, data retrieval, and traversal between nodes of information as well as speeding up the data access rate. They enable related but separate documents to have relationships, and allow the user to explore information naturally through non-linear link traversals. The basic operational requirements of the document viewing system are to: provide an electronic corollary to the current method of paper based document usage; supplement and ultimately replace paper-based documents; maintain focused toward control center operations such as Flight Data File, Flight Rules and Console Handbook viewing; and be available NASA wide.

  7. Essential perspectives for Design for Environment: Experiences from the electronics industry

    NARCIS (Netherlands)

    Boks, C.B.; Stevels, A.L.N.

    2007-01-01

    Consolidation of knowledge, information and experiences in application of Design for Environment principles is done at various levels, ranging from easy to understand slogans to design guidelines, and even to tailor-made solutions. This brings about that dissemination of this knowledge should be

  8. Four Learning Environments for the Contemporary Art Education Classroom: Studio, Information, Planning, and Electronic

    Science.gov (United States)

    Marschalek, Douglas G.

    2004-01-01

    This article provides an overview of a secondary art education methods course developed in response to a variety of educational directives and movements in the fields of art, education, art education, and design. Within each unit of study in this course, students engage in four learning environments--studio, information design, planning, and…

  9. Animated Pedagogical Agents: A Review of Agent Technology Software in Electronic Learning Environments

    Science.gov (United States)

    Govindasamy, Malliga K.

    2014-01-01

    Agent technology has become one of the dynamic and most interesting areas of computer science in recent years. The dynamism of this technology has resulted in computer generated characters, known as pedagogical agent, entering the digital learning environments in increasing numbers. Commonly deployed in implementing tutoring strategies, these…

  10. Essential perspectives for Design for Environment: Experiences from the electronics industry

    NARCIS (Netherlands)

    Boks, C.B.; Stevels, A.L.N.

    2007-01-01

    Consolidation of knowledge, information and experiences in application of Design for Environment principles is done at various levels, ranging from easy to understand slogans to design guidelines, and even to tailor-made solutions. This brings about that dissemination of this knowledge should be don

  11. Electronic Environments for Reading: An Annotated Bibliography of Pertinent Hardware and Software

    NARCIS (Netherlands)

    Koolen, C.; Garnett, A.; Siemens, R.

    2012-01-01

    In the development of new research environments, hardware has often been neglected. E-readers have (reasonably) successfully been developed for leisurely reading, but reading with the goal of writing demands a different approach. This bibliography has been written to inform the INKE research group

  12. Groundwater sustainability in Asian Mega city

    Science.gov (United States)

    Taniguchi, M.

    2009-12-01

    Population increased in many Asian coastal cities, and increased demand of groundwater as water resources caused many subsurface environments. Subsurface environmental problems such as land subsidence due to excessive pumping, groundwater contamination and subsurface thermal anomaly, have occurred repeatedly in Asian mega cities with a time lag depending on the development stage of urbanization. This study focus on four subjects; urban, water, heat, and material in subsurface environment, and intensive field observations and data collections had been made in the basins including Tokyo, Osaka, Bangkok, Jakarta, Manila, Seoul, and Taipei. The new methods for evaluating the changes in groundwater storage by gravimeter measurements in situ and Satellite GRACE, and residence time evaluation by 85Kr and CFCs, have been developed in this study. The combined effects of heat island and global warming from subsurface temperature in Asian mega cities evaluated the magnitude and timing of the urbanization which were preserved in subsurface thermal environment. The effects of law/institution on change in reliable water resources between groundwater and surface water, have been also investigated. The groundwater is “private water”, on the other hand, the surface water is “public water”. Regulation of groundwater pumping due to serious land subsidence did not work without alternative water resources, and the price of water is another major factor for the change in reliable water resources between groundwater and surface water. Land use/cover changes at three ages (1940’s, 1970’s and 2000’s) have been analyzed based on GIS with 0.5 km grid at seven targeted cities. The development of integrated indicators based on GIS for understanding the relationship between human activities and subsurface environment have been made in this study. Finally, we address the sustainable use of groundwater and subsurface environments for better future development and human well-being.

  13. Catalytic consequences of the structural environment and electronics of Ti in grafted Ti-calixarenes

    Energy Technology Data Exchange (ETDEWEB)

    Notestein, Justin M.; Katz, Alexander; Iglesia, Enrique [University of California, Berkeley, CA (United States). Dept. of Chemical Engineering; Andrini, Leandro R.; Requejo, Felix G. [Universidad Nacional de La Plata (Argentina). Inst. de Fisica; Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina). Facultad de Ciencias Exactas. Dept. de Fisica; Kalchenko, Vitaly I. [National Academy of Sciences (Ukraine). Inst. of Organic Chemistry

    2008-11-15

    Calixarene-metal complexes provide the opportunity for fundamental studies to correlate basic characteristics and properties of molecules and atomic species. In particular because grafted Ti-calixarenes provide Ti centers with varying electron density and coordination but maintain accessible sites (active centers) with uniform structures and unrestricted access to reactants, they allow for a systematic approach to relating oxidation reactivity to Ti 3d occupancy, a descriptor of Lewis acid strength, and Ti coordination. Thus, the relationship between activity, geometry and concepts of electronics in catalysis can be revisited and clarified due to the well-defined nature of these Ti sites, allied to the chemical and local sensitivity of X-ray absorption techniques. (author)

  14. Preliminary design of CERN Future Circular Collider tunnel: first evaluation of the radiation environment in critical areas for electronics

    Science.gov (United States)

    Infantino, Angelo; Alía, Rubén García; Besana, Maria Ilaria; Brugger, Markus; Cerutti, Francesco

    2017-09-01

    As part of its post-LHC high energy physics program, CERN is conducting a study for a new proton-proton collider, called Future Circular Collider (FCC-hh), running at center-of-mass energies of up to 100 TeV in a new 100 km tunnel. The study includes a 90-350 GeV lepton collider (FCC-ee) as well as a lepton-hadron option (FCC-he). In this work, FLUKA Monte Carlo simulation was extensively used to perform a first evaluation of the radiation environment in critical areas for electronics in the FCC-hh tunnel. The model of the tunnel was created based on the original civil engineering studies already performed and further integrated in the existing FLUKA models of the beam line. The radiation levels in critical areas, such as the racks for electronics and cables, power converters, service areas, local tunnel extensions was evaluated.

  15. Helium-Charged Titanium Films Deposited by Pulsed Laser Deposition in an Electron-Cyclotron-Resonance Helium Plasma Environment

    Institute of Scientific and Technical Information of China (English)

    金钦华; 胡佩钢; 凌浩; 吴嘉达; 施立群; 周筑颖

    2003-01-01

    Titanium thin films incorporated with helium are produced by pulsed laser deposition in an electron cyclotron resonance helium plasma environment. Helium is distributed evenly in the film and a relatively high He/Ti atomic ratio (~ 20%) is obtained from the proton backscattering spectroscopy. This high concentration ofhelium leads to a surface blistering which is observed by scanning electron microscopy. Laser repetition rate has little influence on film characters. Substrate bias voltage is also changed for the helium incorporating mechanism study, and this is a helium ion implantation process during the film growth. Choosing suitable substrate bias voltage, one can avoid the damage produced by ion implantation, which is always present in general implantation case.

  16. Extensible and object-oriented system Eos supplies a new environment for image analysis of electron micrographs of macromolecules.

    Science.gov (United States)

    Yasunaga, T; Wakabayashi, T

    1996-01-01

    To study macromolecular structure by electron microscopy, a highly extensible and object-oriented system has been developed for image analysis. This system is named "Eos" (Extensible and object-oriented system). The system described here supplies an environment with four types of supports: (i) a group of small tools for image analysis, (ii) tools for integration of small tools, such as "Display2," (iii) tools for development, such as "maketool," and (iv) object-oriented libraries for development of new tools. Using Eos, electron micrographs can be analyzed by small tools and integration tools. In addition, Eos can be used to develop new tools based on new ideas because development tool and object-oriented libraries are provided. The examples of implemented small tools for image analysis include three-dimensional reconstruction of objects with helical symmetry, cluster analysis, and contour expression.

  17. Effects of electron irradiation in space environment on thermal and mechanical properties of carbon fiber/bismaleimide composite

    Science.gov (United States)

    Yu, Qi; Chen, Ping; Gao, Yu; Ma, Keming; Lu, Chun; Xiong, Xuhai

    2014-10-01

    The effects of electron irradiation in simulated space environment on thermal and mechanical properties of high performance carbon fiber/bismaleimide composites were investigated. The dynamic mechanical properties of the composites exposed to different fluences of electron irradiation were evaluated by Dynamic mechanical analysis (DMA). Thermogravimetric analysis was applied to investigate the changes in thermal stability of the resin matrix after exposure to electron irradiation. The changes in mechanical properties of the composites were evaluated by flexural strength and interlaminar shear strength (ILSS). The results indicated that electron irradiation in high vacuum had an impact on thermal and mechanical properties of CF/BMI composites, which depends on irradiation fluence. At lower irradiation fluences less than 5 × 1015 cm-2, the dynamic storage modulus, cross-linking degree, thermal stability and mechanical properties that were determined by a competing effect between chain scission and cross-linking process, decreased firstly and then increased. While at higher fluences beyond 5 × 1015 cm-2, the chain scission process was dominant and thus led to the degradation in thermal and mechanical properties of the composites.

  18. ScoPe system for electronic learning in the practical community environment

    OpenAIRE

    2012-01-01

    The aim of the paper is the research of the effects of social connection to the process of education and to test the sustainability of the idea about the free exchange of knowledge in the students' population, with the means of development of special system of electronic learning, which is based on the principles of virtual practical communities. Apart from the theoretical analysis of the references about practical communities, in the paper, by the method of case study, the process of develop...

  19. Research of the radiation tolerance in space environment of general electronic devices

    OpenAIRE

    Maeda, Takahiro; Kakimi, Yukitaka; Akashi, Kenji; Oshima, Takeshi; Onoda, Shinobu

    2013-01-01

    In small satellite development, general electronic (COTS) devices are needed to use due to some severe restrictions of resource for installed components. For this reason, it is important to keep reliability for using COTS devices in small satellite development. Therefore, in order to ensure reliability for small satellite, our company has evaluated COTS devices mainly for tolerance of single event at Japan Atomic Energy Agency (JAEA) Takasaki Advanced Radiation Research Institute from fiscal ...

  20. 40 CFR 258.53 - Ground-water sampling and analysis requirements.

    Science.gov (United States)

    2010-07-01

    ....53 Ground-water sampling and analysis requirements. (a) The ground-water monitoring program must... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water sampling and analysis requirements. 258.53 Section 258.53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)...

  1. Avoiding artefacts during electron microscopy of silver nanomaterials exposed to biological environments.

    Science.gov (United States)

    Chen, S; Goode, A E; Skepper, J N; Thorley, A J; Seiffert, J M; Chung, K F; Tetley, T D; Shaffer, M S P; Ryan, M P; Porter, A E

    2016-02-01

    Electron microscopy has been applied widely to study the interaction of nanomaterials with proteins, cells and tissues at nanometre scale. Biological material is most commonly embedded in thermoset resins to make it compatible with the high vacuum in the electron microscope. Room temperature sample preparation protocols developed over decades provide contrast by staining cell organelles, and aim to preserve the native cell structure. However, the effect of these complex protocols on the nanomaterials in the system is seldom considered. Any artefacts generated during sample preparation may ultimately interfere with the accurate prediction of the stability and reactivity of the nanomaterials. As a case study, we review steps in the room temperature preparation of cells exposed to silver nanomaterials (AgNMs) for transmission electron microscopy imaging and analysis. In particular, embedding and staining protocols, which can alter the physicochemical properties of AgNMs and introduce artefacts thereby leading to a misinterpretation of silver bioreactivity, are scrutinized. Recommendations are given for the application of cryogenic sample preparation protocols, which simultaneously fix both particles and diffusible ions. By being aware of the advantages and limitations of different sample preparation methods, compromises or selection of different correlative techniques can be made to draw more accurate conclusions about the data.

  2. Graphical overview and navigation of electronic health records in a prototyping environment using Google Earth and openEHR archetypes.

    Science.gov (United States)

    Sundvall, Erik; Nyström, Mikael; Forss, Mattias; Chen, Rong; Petersson, Håkan; Ahlfeldt, Hans

    2007-01-01

    This paper describes selected earlier approaches to graphically relating events to each other and to time; some new combinations are also suggested. These are then combined into a unified prototyping environment for visualization and navigation of electronic health records. Google Earth (GE) is used for handling display and interaction of clinical information stored using openEHR data structures and 'archetypes'. The strength of the approach comes from GE's sophisticated handling of detail levels, from coarse overviews to fine-grained details that has been combined with linear, polar and region-based views of clinical events related to time. The system should be easy to learn since all the visualization styles can use the same navigation. The structured and multifaceted approach to handling time that is possible with archetyped openEHR data lends itself well to visualizing and integration with openEHR components is provided in the environment.

  3. Nonequilibrium electron transport in a hybrid superconductor-normal metal entangler in a dissipative environment

    Science.gov (United States)

    Bubanja, Vladimir; Yamamoto, Mayumi; Iwabuchi, Shuichi

    2016-11-01

    We consider a three-terminal Cooper-pair splitting device with a superconducting electrode tunnel coupled to two normal metal electrodes. We employ the Nambu-Gor'kov and Schwinger-Keldysh formalisms to describe the nonequilibrium transport properties of the device for arbitrary transmissions of the barriers and for a general electromagnetic environment. We derive the analytic expressions for the current and the nonlocal differential conductance, and analyze the limits of clean and dirty superconductivity.

  4. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2011-01-01

    Most people think of groundwater as a resource, but it is also a useful indicator of climate variability and human impacts on the environment. Groundwater storage varies slowly relative to other non-frozen components of the water cycle, encapsulating long period variations and trends in surface meteorology. On seasonal to interannual timescales, groundwater is as dynamic as soil moisture, and it has been shown that groundwater storage changes have contributed to sea level variations. Groundwater monitoring well measurements are too sporadic and poorly assembled outside of the United States and a few other nations to permit direct global assessment of groundwater variability. However, observational estimates of terrestrial water storage (TWS) variations from the GRACE satellites largely represent groundwater storage variations on an interannual basis, save for high latitude/altitude (dominated by snow and ice) and wet tropical (surface water) regions. A figure maps changes in mean annual TWS from 2009 to 2010, based on GRACE, reflecting hydroclimatic conditions in 2010. Severe droughts impacted Russia and the Amazon, and drier than normal weather also affected the Indochinese peninsula, parts of central and southern Africa, and western Australia. Groundwater depletion continued in northern India, while heavy rains in California helped to replenish aquifers that have been depleted by drought and withdrawals for irrigation, though they are still below normal levels. Droughts in northern Argentina and western China similarly abated. Wet weather raised aquifer levels broadly across western Europe. Rains in eastern Australia caused flooding to the north and helped to mitigate a decade long drought in the south. Significant reductions in TWS seen in the coast of Alaska and the Patagonian Andes represent ongoing glacier melt, not groundwater depletion. Figures plot time series of zonal mean and global GRACE derived non-seasonal TWS anomalies (deviation from the mean of

  5. STRATEGIC ISSUES GROUNDWATER EXTRACTION MANAGEMENT IN RUSSIA

    Directory of Open Access Journals (Sweden)

    Ekaterina I. Golovina

    2017-05-01

    Full Text Available Water is a key component of our environment; it is a renewable, limited and vulnerable natural resource, which provides economic, social, and environmental well-being of the population. The most promising source of drinking water supply is groundwater usage. Drinking and industrial groundwater is one of the most important components of the groundwater mineral resource base in the Russian Federation. Modern system of groundwater extraction management and state regulation is currently imperfect and has definite disadvantages, among them - lack of control over natural resources by the state, an old system of tax rates for the use of groundwater, commercialization stage of licensing, the budget deficit, which is passed on other spheres of the national economy. This article provides general information about the state of groundwater production and supply in Russia, negative trends of groundwater usage, some actions for the improvement in the system of groundwater’s fund management are suggested. The most important amendments of the law “About mineral resources” are overviewed, effects of these changes are revealed and recommendations for future groundwater extraction regulation are given.

  6. RECOGNIZING PERSONAL LEARNING STYLES AND USING LEARNING STRATEGIES WHILE LEARNING ENGLISH IN AN ELECTRONIC ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Jurickova, Radka

    2013-06-01

    Full Text Available This paper describes the development of language skills among academics of VSB-Technical University of Ostrava in an LMS Moodle e-learning environment with regard to individual learning styles and strategies while learning a foreign language. A student’s individual learning style plays an essential role in effective foreign language acquisition, therefore recognizing their own learning style and using the right strategies to reinforce their particular curriculum can lead to effective learning. The Department of Languages at the VSB-Technical University of Ostrava has decided to implement e-learning forms of education into English Language Teaching (ELT in the form of optimized adaptive e-courses. The paper describes the objective of providing an optimized adaptive e-learning environment respecting preferred learning styles with a narrower focus on the perceptual preferences (VAK of the presented curriculum and with regard to recommended learning strategies to be used while learning. This e-learning environment is being developed in accordance with the Common European Framework of References for Languages and its key language competences divided into two main categories: receptive skills and productive skills.

  7. Burn site groundwater interim measures work plan.

    Energy Technology Data Exchange (ETDEWEB)

    Witt, Jonathan L. (North Wind, Inc., Idaho Falls, ID); Hall, Kevin A. (North Wind, Inc., Idaho Falls, ID)

    2005-05-01

    This Work Plan identifies and outlines interim measures to address nitrate contamination in groundwater at the Burn Site, Sandia National Laboratories/New Mexico. The New Mexico Environment Department has required implementation of interim measures for nitrate-contaminated groundwater at the Burn Site. The purpose of interim measures is to prevent human or environmental exposure to nitrate-contaminated groundwater originating from the Burn Site. This Work Plan details a summary of current information about the Burn Site, interim measures activities for stabilization, and project management responsibilities to accomplish this purpose.

  8. Electronic structure of quantum dots: response to the environment and externally applied fields

    OpenAIRE

    Segarra Ortí, Carlos

    2016-01-01

    En esta Tesis Doctoral se han estudiado teóricamente las propiedades electrónicas y ópticas de electrones y huecos confinados en puntos cuánticos semiconductores mediante el uso del método k·p dentro de las aproximaciones de masa efectiva y de función envolvente. Para tal fin, se han desarrollado modelos computacionales capaces de describir adecuadamente la estructura electrónica de las bandas de conducción y valencia de sistemas sometidos a varios fenómenos de interés. En concreto, se ha pre...

  9. Assessment of Accrued Damage and Remaining Useful Life in Leadfree Electronics Subjected to Multiple Thermal Environments of Thermal Aging and Thermal Cycling

    Data.gov (United States)

    National Aeronautics and Space Administration — A method has been developed for prognostication of accrued prior damage in electronics subjected to overlapping sequential environments of thermal aging and thermal...

  10. The Effect of Solvent Environment on Molecular Electronic Transition Moment Directions

    DEFF Research Database (Denmark)

    Langkilde, F. W.; Thulstrup, E. W.; Michl, J.

    1983-01-01

    Measurements of polarized fluorescence and phosphorescence of pyrene, 2‐fluoropyrene, and 2‐methylpyrene in 3‐methylpentane glass at 77 K reveal significant differences among the three molecules. These are interpreted in terms of solvent‐induced mixing of the Lb and La states. It is proposed that...... that such symmetry‐lowering effects of the solvent environment may well be important contributors to the often observed discrepancies between the theoretical limiting values of polarization ratios and the values actually observed....

  11. Groundwater recharge: Accurately representing evapotranspiration

    CSIR Research Space (South Africa)

    Bugan, Richard DH

    2011-09-01

    Full Text Available Groundwater recharge is the basis for accurate estimation of groundwater resources, for determining the modes of water allocation and groundwater resource susceptibility to climate change. Accurate estimations of groundwater recharge with models...

  12. 地下水生态环境与社会经济协调发展定量分析%Quantitative Analysis of Coordination between Groundwater Environment and Socio-Economic Development

    Institute of Scientific and Technical Information of China (English)

    王海宁; 薛惠锋

    2012-01-01

    This paper described the method of minimizing deviation coefficient to establish a quantitative model for evaluation of the coordination between groundwater environment and socio-economic development in the Guanzhong Plain of , Shannxi Province. Result of the evaluation revealed the coordination levels differed from the region to region within the Plain comprising Baoji, Xi'an, Xianyang and Weinan. Since groundwater is the key water resource for all of these regions in terms of both domestic and industrial use, proposals for increasing the carrying capacity, and for efficient utilization of groundwater, are put forward in the paper.%采用离差系数最小化方法建立地下水生态环境与社会经济协调发展定量评价模型.依据协调度的取值范围,将协调发展类型分为30种基本发展类型.在构建地下水生态环境与社会经济协调发展评价指标体系的基础上,文章以关中地区5个行政区为研究载体,分析地下水生态环境与社会经济发展之间的互动关系.评价结果表明:关中地区地下水生态环境与社会经济发展的协调度比较高,但处于生态环境与社会经济发展程度较低状态下的协调发展.其中,宝鸡属于良好协调发展环境滞后型,西安、咸阳、渭南属于中级协调发展经济滞后型,铜川属于初级协调发展经济滞后型.文章对评价结果进行综合诊断,提出促进地下水生态环境与社会经济之间协调发展的对策建议.

  13. Gamow-Teller strength distributions at finite temperatures and electron capture in stellar environments

    CERN Document Server

    Dzhioev, Alan A; Ponomarev, V Yu; Wambach, J; Langanke, K; Martínez-Pinedo, G

    2009-01-01

    We propose a new method to calculate stellar weak-interaction rates. It is based on the Thermo-Field-Dynamics formalism and allows the calculation of the weak-interaction response of nuclei at finite temperatures. The thermal evolution of the GT$_+$ distributions is presented for the sample nuclei $^{54, 56}$Fe and ~$^{76,78,80}$Ge. For Ge we also calculate the strength distribution of first-forbidden transitions. We show that thermal effects shift the GT$_+$ centroid to lower excitation energies and make possible negative- and low-energy transitions. In our model we demonstrate that the unblocking effect for GT$_+$ transitions in neutron-rich nuclei is sensitive to increasing temperature. The results are used to calculate electron capture rates and are compared to those obtained from the shell model.

  14. A Way to Understand Inpatients Based on the Electronic Medical Records in the Big Data Environment

    Directory of Open Access Journals (Sweden)

    Hongyi Mao

    2017-01-01

    Full Text Available In recent decades, information technology in healthcare, such as Electronic Medical Record (EMR system, is potential to improve service quality and cost efficiency of the hospital. The continuous use of EMR systems has generated a great amount of data. However, hospitals tend to use these data to report their operational efficiency rather than to understand their patients. Base on a dataset of inpatients’ medical records from a Chinese general public hospital, this study applies a configuration analysis from a managerial perspective and explains inpatients management in a different way. Four inpatient configurations (valued patients, managed patients, normal patients, and potential patients are identified by the measure of the length of stay and the total hospital cost. The implications of the finding are discussed.

  15. A Way to Understand Inpatients Based on the Electronic Medical Records in the Big Data Environment

    Science.gov (United States)

    2017-01-01

    In recent decades, information technology in healthcare, such as Electronic Medical Record (EMR) system, is potential to improve service quality and cost efficiency of the hospital. The continuous use of EMR systems has generated a great amount of data. However, hospitals tend to use these data to report their operational efficiency rather than to understand their patients. Base on a dataset of inpatients' medical records from a Chinese general public hospital, this study applies a configuration analysis from a managerial perspective and explains inpatients management in a different way. Four inpatient configurations (valued patients, managed patients, normal patients, and potential patients) are identified by the measure of the length of stay and the total hospital cost. The implications of the finding are discussed. PMID:28280506

  16. An Electron Microscope Study on Different Spent Mushroom in a Compost Environment

    Directory of Open Access Journals (Sweden)

    Anlong Zou

    2015-09-01

    Full Text Available In this study, we used Lentinus edodes residues (XG and Pleurotus ostreatus (PG as compost materials and used a high-temperature static aerobic composting system to examine the effects of different treatment. We analyzed changes in temperature and compost structure during the process of composting. The study showed that XG and PG mixed by 1:1 increased the temperature of the compost pile and reached to the environmental temperature more rapidly. Mix treatment had maximum temperature of 71°C, had longest megathermal period continued about 9 days than other groups. Scanning Electron Microscope (SEM showed mix treatment had the best lignin structure variation trend while PG had the worst. Thus, mix treatment significantly increased the composting rate, reaching complete decomposition 10 days before other treatments. These data also suggested that XG as a compost material is better that PG.

  17. Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework

    Energy Technology Data Exchange (ETDEWEB)

    Morzan, Uriel N.; Ramírez, Francisco F.; Scherlis, Damián A., E-mail: damian@qi.fcen.uba.ar, E-mail: mcgl@qb.ffyb.uba.ar [Departamento de Química Inorgánica, Analítica y Química Física/INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. II, Buenos Aires (C1428EHA) (Argentina); Oviedo, M. Belén; Sánchez, Cristián G. [Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba (Argentina); Lebrero, Mariano C. González, E-mail: damian@qi.fcen.uba.ar, E-mail: mcgl@qb.ffyb.uba.ar [Instituto de Química y Fisicoquímica Biológicas, IQUIFIB, CONICET (Argentina)

    2014-04-28

    This article presents a time dependent density functional theory (TDDFT) implementation to propagate the Kohn-Sham equations in real time, including the effects of a molecular environment through a Quantum-Mechanics Molecular-Mechanics (QM-MM) hamiltonian. The code delivers an all-electron description employing Gaussian basis functions, and incorporates the Amber force-field in the QM-MM treatment. The most expensive parts of the computation, comprising the commutators between the hamiltonian and the density matrix—required to propagate the electron dynamics—, and the evaluation of the exchange-correlation energy, were migrated to the CUDA platform to run on graphics processing units, which remarkably accelerates the performance of the code. The method was validated by reproducing linear-response TDDFT results for the absorption spectra of several molecular species. Two different schemes were tested to propagate the quantum dynamics: (i) a leap-frog Verlet algorithm, and (ii) the Magnus expansion to first-order. These two approaches were confronted, to find that the Magnus scheme is more efficient by a factor of six in small molecules. Interestingly, the presence of iron was found to seriously limitate the length of the integration time step, due to the high frequencies associated with the core-electrons. This highlights the importance of pseudopotentials to alleviate the cost of the propagation of the inner states when heavy nuclei are present. Finally, the methodology was applied to investigate the shifts induced by the chemical environment on the most intense UV absorption bands of two model systems of general relevance: the formamide molecule in water solution, and the carboxy-heme group in Flavohemoglobin. In both cases, shifts of several nanometers are observed, consistently with the available experimental data.

  18. Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework.

    Science.gov (United States)

    Morzan, Uriel N; Ramírez, Francisco F; Oviedo, M Belén; Sánchez, Cristián G; Scherlis, Damián A; Lebrero, Mariano C González

    2014-04-28

    This article presents a time dependent density functional theory (TDDFT) implementation to propagate the Kohn-Sham equations in real time, including the effects of a molecular environment through a Quantum-Mechanics Molecular-Mechanics (QM-MM) hamiltonian. The code delivers an all-electron description employing Gaussian basis functions, and incorporates the Amber force-field in the QM-MM treatment. The most expensive parts of the computation, comprising the commutators between the hamiltonian and the density matrix-required to propagate the electron dynamics-, and the evaluation of the exchange-correlation energy, were migrated to the CUDA platform to run on graphics processing units, which remarkably accelerates the performance of the code. The method was validated by reproducing linear-response TDDFT results for the absorption spectra of several molecular species. Two different schemes were tested to propagate the quantum dynamics: (i) a leap-frog Verlet algorithm, and (ii) the Magnus expansion to first-order. These two approaches were confronted, to find that the Magnus scheme is more efficient by a factor of six in small molecules. Interestingly, the presence of iron was found to seriously limitate the length of the integration time step, due to the high frequencies associated with the core-electrons. This highlights the importance of pseudopotentials to alleviate the cost of the propagation of the inner states when heavy nuclei are present. Finally, the methodology was applied to investigate the shifts induced by the chemical environment on the most intense UV absorption bands of two model systems of general relevance: the formamide molecule in water solution, and the carboxy-heme group in Flavohemoglobin. In both cases, shifts of several nanometers are observed, consistently with the available experimental data.

  19. Improving Working Conditions for Astronauts: An Electronic Personal Restraint System for Use in Microgravity Environments

    Directory of Open Access Journals (Sweden)

    Kevin Tait

    2012-01-01

    Full Text Available While in microgravity, astronauts are preoccupied with physical restraint, which takes attention away from the maintenance task or scientific experiment at hand. This may directly lead to safety concerns and increased time for extravehicular activity, as well as potentially inhibit or corrupt data collection. A primary concern is the time it takes to manipulate the current restraint system. The portable foot restraint currently in use by NASA employs a series of pins in order to engage the system or release in an emergency. This requires considerable time for the user to detach, and there is an increased risk of entanglement. If restraint operating time could be reduced by 50%, the astronaut’s assigned experiment time could be increased an average of 100 minutes per mission. Another problem identified by NASA included the inability of the current system to release the user upon failure. Research and design was conducted following the Six-Sigma DMEDI project architecture, and a new form of restraint to replace the existing system was proposed. The research team first studied the customer requirements and relevant standards set by NASA, and with this information they began drafting designs for a solution. This project utilized electromagnetism to restrain a user in microgravity. The proposed system was capable of being manipulated quickly, failing in a manner that released the user, and being electronically controlled. This active electronic control was a new concept in restraint systems, as it enabled an astronaut to effectively “walk” along a surface while remaining restrained to it. With the design prototype and a limited budget, a rudimentary test assembly was built by the team, and most of NASA’s specifications were met. With recommendations from NASA, the research team concluded by developing potential material and design solutions that can be explored in the future by Purdue University or other parties.

  20. Effects of the dielectric environment on the electron transport properties of single-layer MoS2

    Science.gov (United States)

    Bertolazzi, Simone; Allain, Adrien; Lembke, Dominik; Kis, Andras

    2014-03-01

    Two-dimensional materials, such as graphene, boron nitride and transition metal dichalcogenides, offer a wide range of electronic, optical and mechanical properties that can be advantageous for several applications in nanotechnology. Among these materials, single-layer molybdenum disulfide (MoS2) shows great potential for scaling field-effect transistor devices, due to an optimal electrostatic control of the 2D semiconducting sheet, large energy bandgap and minimal leakage currents. However, to fully exploit the potential of this atomically thin semiconductor, additional experimental efforts need to be undertaken to boost the device performance and access the theoretical intrinsic electron mobilities. To pursue this objective, it is mandatory to reduce the density of charged impurities, both in the semiconducting sheet and in its surrounding environment, and to limit carrier scattering induced by polar optical phonons in the dielectric surface. Here we present the results of our recent experimental investigation of the electron transport properties of single-layer MoS2 mechanically exfoliated/transferred onto different substrates, with varying surface chemistry, surface roughness and dielectric permittivity. We will show temperature-dependent four-terminal measurements of the electrical conductivity of single-layer MoS2 in contact with various insulating materials, including 2D sheets of hexagonal boron nitride, organic polymers and metal oxides.

  1. Characterization of attached bacterial populations in deep granitic groundwater from the Stripa research mine by 16S rRNA gene sequencing and scanning electron microscopy.

    Science.gov (United States)

    Ekendahl, S; Arlinger, J; Ståhl, F; Pedersen, K

    1994-07-01

    This paper presents the molecular characterization of attached bacterial populations growing in slowly flowing artesian groundwater from deep crystalline bed-rock of the Stripa mine, south central Sweden. Bacteria grew on glass slides in laminar flow reactors connected to the anoxic groundwater flowing up through tubing from two levels of a borehole, 812-820 m and 970-1240 m. The glass slides were collected, the bacterial DNA was extracted and the 16S rRNA genes were amplified by PCR using primers matching universally conserved positions 519-536 and 1392-1405. The resulting PCR fragments were subsequently cloned and sequenced. The sequences were compared with each other and with 16S rRNA gene sequences in the EMBL database. Three major groups of bacteria were found. Signature bases placed the clones in the appropriate systematic groups. All belonged to the proteobacterial groups beta and gamma. One group was found only at the 812-820 m level, where it constituted 63% of the sequenced clones, whereas the second group existed almost exclusively at the 970-1240 m level, where it constituted 83% of the sequenced clones. The third group was equally distributed between the levels. A few other bacteria were also found. None of the 16S rRNA genes from the dominant bacteria showed more than 88% similarity to any of the others, and none of them resembled anything in the database by more than 96%. Temperature did not seem to have any effect on species composition at the deeper level. SEM images showed rods appearing in microcolonies.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Groundwater Managment Districts

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset outlines the location of the five Groundwater Management Districts in Kansas. GMDs are locally formed and elected boards for regional groundwater...

  3. Geochemical Investigations of Groundwater Stability

    Energy Technology Data Exchange (ETDEWEB)

    Bath, Adrian [Intellisci Ltd., Loughborough (United Kingdom)

    2006-05-15

    groundwaters, and also by stable isotopes and uranium isotopes in secondary minerals. Information on timing of water and solute movements is important because it indicates any correlation with the timing of external events that might have perturbed and destabilised the groundwater system in the past, and allows a timescale to be estimated for the persistence of stable conditions. Data from a number of published site investigation projects and research programmes are reviewed to illustrate the patterns of geochemical data and the relationships between them, and how these are interpreted in terms of hydrodynamic stability. Data from Aespoe and Stripa and from exploratory boreholes at Finnsjoen and other sites in Sweden are compiled and discussed. Preliminary data from SKB's ongoing site investigations at Simpevarp/Laxemar and Forsmark are not considered in detail but their general similarities with Aespoe and Finnsjoen/SFR respectively are introduced into the discussion of geochemical evidence for groundwater stability in inland and coastal areas. Relevant data from Finnish sites including Olkiluoto, from the Whiteshell URL area in Canada, from Sellafield in the UK, and from the Tono area and URL in Japan are also summarised in appendices and discussed because they add further insights into the interpretation of geochemical indicators for a range of geological environments. The compiled data provide only limited scope for comparison of groundwater evolution and stability between inland and coastal areas in Sweden, because of the patchiness of representative data especially from early site studies. The external changes that might have perturbed stable groundwater conditions in the past are glaciation (i.e. melt water, mechanical loading/unloading and permafrost) and varying sea water infiltration at coastal sites due to changes in palaeo-Baltic and isostatic conditions. The present distributions of palaeo-Baltic sea water in groundwaters at coastal sites vary, reflecting

  4. Bioremediation of contaminated groundwater

    Science.gov (United States)

    Hazen, Terry C.; Fliermans, Carl B.

    1995-01-01

    An apparatus and method for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid is selected to stimulate the growth and reproduction of indigenous subsurface microorganisms that are capable of degrading the contaminants; an oxygenated fluid is selected to create a generally aerobic environment for these microorganisms to degrade the contaminants, leaving only pockets that are anaerobic. The nutrient fluid is injected periodically while the oxygenated fluid is injected continuously and both are extracted so that both are drawn across the plume. The nutrient fluid stimulates microbial colony growth; withholding it periodicially forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is reduced to an acceptable, preselected level. The nutrient fluid can be methane and the oxygenated fluid air for stimulating production of methanotrophs to break down chlorohydrocarbons, especially trichloroethylene (TCE) and tetrachloroethylene.

  5. Communication Patterns in the Perioperative Environment During Epic Electronic Health Record System Implementation.

    Science.gov (United States)

    Friend, Tynan H; Jennings, Samantha J; Levine, Wilton C

    2017-02-01

    In April 2016, Massachusetts General Hospital (MGH) went live with the Epic electronic health records (EHR) system, replacing a variety of EHRs that previously existed in different departments throughout the hospital. At the time of implementation, the Vocera® Badge Communication System, a wireless hands-free communication device distributed to perioperative team members, had increased perioperative communication flow and efficiency. As a quality improvement effort to better understand communication patterns during an EHR go-live, we monitored our Vocera call volume and user volume before, during and after our go-live. We noticed that call volume and user volume significantly increased during our immediate go-live period and quickly returned to baseline levels. We also noticed that call volume increased during periods of unplanned EHR downtime long after our immediate go-live period. When planning the implementation of a new EHR, leadership must plan for and support this critical communication need at the time of the go-live and must also be aware of these needs during unplanned downtime.

  6. Electronic Engineering Notebook: A software environment for research execution, documentation and dissemination

    Science.gov (United States)

    Moerder, Dan

    1994-01-01

    The electronic engineering notebook (EEN) consists of a free form research notebook, implemented in a commercial package for distributed hypermedia, which includes utilities for graphics capture, formatting and display of LaTex constructs, and interfaces to the host operating system. The latter capability consists of an information computer-aided software engineering (CASE) tool and a means to associate executable scripts with source objects. The EEN runs on Sun and HP workstations. The EEN, in day-to-day use can be used in much the same manner as the sort of research notes most researchers keep during development of projects. Graphics can be pasted in, equations can be entered via LaTex, etc. In addition, the fact that the EEN is hypermedia permits easy management of 'context', e.g., derivations and data can contain easily formed links to other supporting derivations and data. The CASE tool also permits development and maintenance of source code directly in the notebook, with access to its derivations and data.

  7. Electron capture strength on odd-A nucleus $\\mathbf{^{59}}$Co in explosive astrophysical environment

    CERN Document Server

    Rahman, Muneeb-Ur

    2014-01-01

    The Gamow-Teller (GT) transitions within massive stars play sumptuous role in the dynamics of core collapse supernovae. GT strength distributions and electron capture rates have been calculated for odd-A nucleus $^{59}$Co within the proton-neutron quasiparticles random phase approximation (pn-QRPA) formalism. The pn-QRPA results are compared with other model calculations and (n, p) reaction experiment carried out at TRIUMF charge-exchange facility. The pn-QRPA calculated a total $B(GT_{+})$ strength of 3.3 for $^{59}$Co to be compared with the shell model value of 2.5 and the 1.9 $\\pm$ 0.1 in the (n, p) charge-exchange reaction. Aufderheide et. al. \\cite{Aufderheide93} extracted total strength equaling 2.4 $\\pm$ 0.3. The placement of GT centroid at 5.6 MeV by the pn-QRPA model is in reasonable agreement with the shell model centroid at 5.1 MeV whereas the measured GT centroid was placed at 4.4 $\\pm$ 0.3 MeV in the (n, p) experiment. Fuller, Fowler and Newman (FFN) \\cite{FFN80, FFN82, FFN82b}, placed the GT ce...

  8. Influence of physical factors and geochemical conditions on groundwater acidification during enhanced reductive dechlorination

    Science.gov (United States)

    Brovelli, A.; Barry, D. A.; Robinson, C.; Gerhard, J.

    2010-12-01

    Enhanced reductive dehalogenation is an attractive in situ treatment technology for chlorinated contaminants. The process includes two acid-forming microbial reactions: fermentation of an organic substrate resulting in short-chain fatty acids, and dehalogenation resulting in hydrochloric acid. The accumulation of acids and the resulting drop of groundwater pH are controlled by the mass and distribution of chlorinated solvents in the source zone, type of electron donor, availability of alternative terminal electron acceptors and presence of soil mineral phases able to buffer the pH (such as carbonates). Groundwater acidification may reduce or halt microbial activity, and thus dehalogenation, significantly increasing the time and costs required to remediate the aquifer. For this reason, research in this area is gaining increasing attention. In previous work (Robinson et al., 2009 407:4560, Sci. Tot. Environ, Robinson and Barry, 2009 24:1332, Environ. Model. & Software, Brovelli et al., 2010, submitted), a detailed geochemical and groundwater flow model able to predict the pH change occurring during reductive dehalogenation was developed. The model accounts for the main processes influencing groundwater pH, including the groundwater composition, the electron donor used and soil mineral phase interactions. In this study, the model was applied to investigate how spatial variability occurring at the field scale affects groundwater pH and dechlorination rates. Numerical simulations were conducted to examine the influence of heterogeneous hydraulic conductivity on the distribution of the injected, fermentable substrate and on the accumulation/dilution of the acidic products of reductive dehalogenation. The influence of the geometry of the DNAPL source zone was studied, as well as the spatial distribution of soil minerals. The results of this study showed that the heterogeneous distribution of the soil properties have a potentially large effect on the remediation efficiency

  9. Hydrogeochemical modeling of groundwater chemical environmental evolution in Hebei Plain

    Institute of Scientific and Technical Information of China (English)

    郭永海; 沈照理; 钟佐燊

    1997-01-01

    Using the hydrogeochemical modeling method, the groundwater chemical environmental problems of the Hebei Plain which involve increasing of hardness and total dissolved solids in piedmont area and mixing of saline water with fresh water in middle-eastern area are studied. The water-rock interactions and mass transfer along a ground-water flow path and in mixing processes are calculated. Thus the evolution mechanisms of the groundwater chemical environment are brought to light.

  10. Groundwater in geologic processes, 2nd edition

    Science.gov (United States)

    Ingebritsen, Steven E.; Sanford, Ward E.; Neuzil, Christopher E.

    2006-01-01

    Interest in the role of Groundwater in Geologic Processes has increased steadily over the past few decades. Hydrogeologists and geologists are now actively exploring the role of groundwater and other subsurface fluids in such fundamental geologic processes as crustal heat transfer, ore deposition, hydrocarbon migration, earthquakes, tectonic deformation, diagenesis, and metamorphism.Groundwater in Geologic Processes is the first comprehensive treatment of this body of inquiry. Chapters 1 to 4 develop the basic theories of groundwater motion, hydromechanics, solute transport, and heat transport. Chapter 5 applies these theories to regional groundwater flow systems in a generic sense, and Chapters 6 to 13 focus on particular geologic processes and environments. Relative to the first edition of Groundwater in Geologic Processes , this second edition includes a much more comprehensive treatment of hydromechanics (the coupling of groundwater flow and deformation). It also includes new chapters on "compaction and diagenesis," "metamorphism," and "subsea hydrogeology." Finally, it takes advantage of the substantial body of published research that has appeared since the first edition in 1998. The systematic presentation of theory and application, and the problem sets that conclude each chapter, make this book ideal for undergraduate- and graduate-level geology courses (assuming that the students have some background in calculus and introductory chemistry). It also serves as an invaluable reference for researchers and other professionals in the field

  11. From submarine to lacustrine groundwater discharge

    Science.gov (United States)

    Lewandowski, Jörg; Meinikmann, Karin; Pöschke, Franziska; Nützmann, Gunnar; Rosenberry, Donald O.

    2017-01-01

    Submarine groundwater discharge (SGD) and its role in marine nutrient cycling are well known since the last decade. The freshwater equivalent, lacustrine groundwater discharge (LGD), is often still disregarded, although first reports of LGD are more than 50 years old. We identify nine different reasons why groundwater has long been disregarded in both freshwater and marine environments such as invisibility of groundwater discharge, the size of the interface and its difficult accessibility. Although there are some fundamental differences in the hydrology of SGD and LGD, caused primarily by seawater recirculation that occurs only in cases of SGD, there are also a lot of similarities such as a focusing of discharge to near-shore areas. Nutrient concentrations in groundwater near the groundwater–surface water interface might be anthropogenically enriched. Due to spatial heterogeneity of aquifer characteristics and biogeochemical processes, the quantification of groundwater-borne nutrient loads is challenging. Both nitrogen and phosphorus might be mobile in near-shore aquifers and in a lot of case studies large groundwater-borne nutrient loads have been reported.

  12. δ44/40Ca variability in shallow water carbonates and the impact of submarine groundwater discharge on Ca-cycling in marine environments

    Science.gov (United States)

    Holmden, C.; Papanastassiou, D. A.; Blanchon, P.; Evans, S.

    2012-04-01

    Shallow water carbonates from Florida Bay, the Florida Reef Tract, and a Mexican Caribbean fringing reef at Punta Maroma were studied to determine the range of Ca-isotope variation among a cohort of modern carbonate producers and to look for local-scale Ca-cycling effects. The total range of Ca-isotope fractionation is 0.4‰ at Punta Maroma, yielding an allochem-weighted average δ44/40Ca value of -1.12‰ consistent with bulk sediment from the lagoon with a value of -1.09‰. These values are virtually identical to bulk carbonate sediments from the Florida Reef Tract (-1.11‰) and from one location in Florida Bay (-1.09‰) near a tidal inlet in the Florida Keys. No evidence was found for the ∼0.6‰ fractionation between calcite and aragonite which has been observed in laboratory precipitation experiments. Combining these results with carbonate production modes and δ44/40Ca values for pelagic carbonates taken from the literature, we calculate a weighted average value of -1.12 ± 0.11‰ (2σ) for the global-scale Ca-output flux into carbonate sediments. The δ44/40Ca value of the input Ca-flux from rivers and hydrothermal fluids is -1.01 ± 0.04‰ (2σmean), calculated from literature data that have been corrected for inter-laboratory bias. Assuming that the ocean Ca cycle is in steady state, we calculate a δ44/40Ca value of -1.23 ± 0.23‰ (2σ) for submarine groundwater discharge (SGD) on a global scale. The SGD Ca-flux rivals river flows and mid-ocean ridge hydrothermal vent inputs as a source of Ca to the oceans. It has the potential to differ significantly in its isotopic value from these traditional Ca-inputs in the geological past, and to cause small changes in the δ44/40Ca value of oceans through time. In the innermost water circulation restricted region of northeastern Florida Bay, sediments and waters exhibit a 0.7‰ gradient in δ44/40Ca values decreasing towards the Florida Everglades. This lowering of δ44/40Ca is predominantly caused by

  13. Regional Groundwater Processes and Flow Dynamics from Age Tracer Data

    Science.gov (United States)

    Morgenstern, Uwe; Stewart, Mike K.; Matthews, Abby

    2016-04-01

    Ruahine ranges are accompanied by elevated nitrate concentrations, indicating quick transfer of nitrate from land use activities into the groundwater system. Extremely high recharge rates of >1 m/y for some wells indicate recharge from the river as the main source. Elevated mean rates of oxygen reduction, as deduced from groundwater MRT, may indicate the presence of electron donors in the groundwater system to facilitate microbial reactions and therefore potential for denitrification reactions. Elevated rates of oxygen reduction occur in the upper Manawatu River catchment, consistent with a sample from there having excess nitrogen which is likely to originate from such denitrification reactions.

  14. A New Geochemical Reaction Model for Groundwater Systems

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Through a survey of the literature on geology, hydrogeology and hydrogeochemistry, this paper presents a hydrogeochemical model for the groundwater system in a dross-dumping area of the Shandong Aluminium Plant. It is considered that the groundwater-bearing medium is a mineral aggregate and that the interactions between groundwater and the groundwater-bearing medium can be described as a series of geochemical reactions. On that basis, the principle of minimum energy and the equations of mass balance, electron balance and electric neutrality are applied to construct a linear programming mathematical model for the calculation of mass transfer between water and rock with the simplex method.

  15. Hydrogeology and hydrochemistry of groundwater-dominated lakes

    DEFF Research Database (Denmark)

    Kazmierczak, Jolanta

    and tracking groundwater flow paths and, thus, to determine the source of the water. These observations were confirmed and explained by flow models. The results of the 2D and 3D flow modelling showed that groundwater contribution is 75% of the total water input into the lake, out of which 35% discharges...... is mobilized in the sediments of the old lake/stream bottom due to reductive dissolution of iron hydroxides by organic matter. The process is triggered by the discharge of anoxic groundwater from the deeper parts of the aquifer to the near shore environment. High groundwater seepage rates do not leave enough...

  16. Tapping the Source: A Listing of Groundwater Education Materials Available through the Groundwater Education in Michigan (GEM) Program. Updated.

    Science.gov (United States)

    Michigan State Univ., East Lansing. Inst. of Water Research.

    Established in 1988 through the cooperative efforts of the Institute of Water Research at Michigan State University and the W. K. Kellogg Foundation, the Groundwater Education in Michigan (GEM) program helps people understand the relationship between their actions and the quality of their environment, particularly groundwater. The program has a…

  17. DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

    OpenAIRE

    Hellegers, Petra J.G.J.; Zilberman, David; van Ierland, Ekko C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality.

  18. DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

    OpenAIRE

    Hellegers, Petra J.G.J.; Zilberman, David; van Ierland, Ekko C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality.

  19. Building groundwater modeling capacity in Mongolia

    Science.gov (United States)

    Valder, Joshua F.; Carter, Janet M.; Anderson, Mark T.; Davis, Kyle W.; Haynes, Michelle A.; Dorjsuren Dechinlhundev,

    2016-06-16

    Ulaanbaatar, the capital city of Mongolia (fig. 1), is dependent on groundwater for its municipal and industrial water supply. The population of Mongolia is about 3 million people, with about one-half the population residing in or near Ulaanbaatar (World Population Review, 2016). Groundwater is drawn from a network of shallow wells in an alluvial aquifer along the Tuul River. Evidence indicates that current water use may not be sustainable from existing water sources, especially when factoring the projected water demand from a rapidly growing urban population (Ministry of Environment and Green Development, 2013). In response, the Government of Mongolia Ministry of Environment, Green Development, and Tourism (MEGDT) and the Freshwater Institute, Mongolia, requested technical assistance on groundwater modeling through the U.S. Army Corps of Engineers (USACE) to the U.S. Geological Survey (USGS). Scientists from the USGS and USACE provided two workshops in 2015 to Mongolian hydrology experts on basic principles of groundwater modeling using the USGS groundwater modeling program MODFLOW-2005 (Harbaugh, 2005). The purpose of the workshops was to bring together representatives from the Government of Mongolia, local universities, technical experts, and other key stakeholders to build in-country capacity in hydrogeology and groundwater modeling.A preliminary steady-state groundwater-flow model was developed as part of the workshops to demonstrate groundwater modeling techniques to simulate groundwater conditions in alluvial deposits along the Tuul River in the vicinity of Ulaanbaatar. ModelMuse (Winston, 2009) was used as the graphical user interface for MODFLOW for training purposes during the workshops. Basic and advanced groundwater modeling concepts included in the workshops were groundwater principles; estimating hydraulic properties; developing model grids, data sets, and MODFLOW input files; and viewing and evaluating MODFLOW output files. A key to success was

  20. 40 CFR 264.97 - General ground-water monitoring requirements.

    Science.gov (United States)

    2010-07-01

    ... FACILITIES Releases From Solid Waste Management Units § 264.97 General ground-water monitoring requirements. The owner or operator must comply with the following requirements for any ground-water monitoring... 40 Protection of Environment 25 2010-07-01 2010-07-01 false General ground-water...

  1. Groundwater sustainability strategies

    Science.gov (United States)

    Gleeson, Tom; VanderSteen, Jonathan; Sophocleous, Marios A.; Taniguchi, Makoto; Alley, William M.; Allen, Diana M.; Zhou, Yangxiao

    2010-01-01

    Groundwater extraction has facilitated significant social development and economic growth, enhanced food security and alleviated drought in many farming regions. But groundwater development has also depressed water tables, degraded ecosystems and led to the deterioration of groundwater quality, as well as to conflict among water users. The effects are not evenly spread. In some areas of India, for example, groundwater depletion has preferentially affected the poor. Importantly, groundwater in some aquifers is renewed slowly, over decades to millennia, and coupled climate–aquifer models predict that the flux and/or timing of recharge to many aquifers will change under future climate scenarios. Here we argue that communities need to set multigenerational goals if groundwater is to be managed sustainably.

  2. Characteristics of groundwater recharge on the North China Plain.

    Science.gov (United States)

    Tan, Xiu-Cui; Wu, Jing-Wei; Cai, Shu-Ying; Yang, Jin-Zhong

    2014-01-01

    Groundwater recharge is an important component of the groundwater system. On the North China Plain (NCP), groundwater is the main water supply. Because of large-scale overexploitation, the water table has declined, which has produced severe adverse effects on the environment and ecosystem. In this article, tracer experiment and watershed model were used to calculate and analyze NCP groundwater recharge. In the tracer experiment, average recharge was 108 mm/year and recharge coefficient 0.16. With its improved irrigation, vegetation coverage and evapotranspiration modules, the INFIL3.0 model was used for calculation of groundwater recharge. Regional modeling results showed an average recharge of 102 mm/year and recharge coefficient 0.14, for 2001-2009. These values are very similar to those from the field tracer experiment. Influences in the two methods were analyzed. The results can provide an important reference for NCP groundwater recharge.

  3. Evolution of Quaternary groundwater system in North China Plain

    Institute of Scientific and Technical Information of China (English)

    张宗祜; 施德鸿; 任福弘; 殷正宙; 孙继朝; 张翠云

    1997-01-01

    The Quaternary groundwater system in the North China Plain is formed mainly through the terrestrial water flow action on the united geological and tectonic backgrounds. The analysis of groundwater dynamic field, simulation of groundwater geochemistry, and the 14C dating and extraction of isotope information have provided more evidence for recognizing and assessing the evolution of groundwater circulation system and studying the past global changes. The exploitation and utilization of groundwater on a large scale and overexploitation have given rise to the decline of regional groundwater level, change of flow field, decrease of water resources and downward movement of saline water body. The water environment has entered a new evolution stage in which it is intensely disturbed by the mankind’s activities.

  4. Vulnerability assessment of groundwater-dependent ecosystems based on integrated groundwater flow modell construction

    Science.gov (United States)

    Tóth, Ádám; Simon, Szilvia; Galsa, Attila; Havril, Timea; Monteiro Santos, Fernando A.; Müller, Imre; Mádl-Szőnyi, Judit

    2017-04-01

    Groundwater-dependent ecosystems (GDEs) are highly influenced by the amount of groundwater, seasonal variation of precipitation and consequent water table fluctuation and also the anthropogenic activities. They can be regarded as natural surface manifestations of the flowing groundwater. The preservation of environment and biodiversity of these GDEs is an important issue worldwide, however, the water management policy and action plan could not be constructed in absense of proper hydrogeological knowledge. The concept of gravity-driven regional groundwater flow could aid the understanding of flow pattern and interpretation of environmental processes and conditions. Unless the required well data are available, the geological-hydrogeological numerical model of the study area cannot be constructed based only on borehole information. In this case, spatially continuous geophysical data can support groundwater flow model building: systematically combined geophysical methods can provide model input. Integration of lithostratigraphic, electrostratigraphic and hydrostratigraphic information could aid groundwater flow model construction: hydrostratigraphic units and their hydraulic behaviour, boundaries and geometry can be obtained. Groundwater-related natural manifestations, such as GDEs, can be explained with the help of the revealed flow pattern and field mapping of features. Integrated groundwater flow model construction for assessing the vulnerability of GDEs was presented via the case study of the geologically complex area of Tihany Peninsula, Hungary, with the aims of understanding the background and occurrence of groundwater-related environmental phenomena, surface water-groundwater interaction, and revealing the potential effect of anthropogenic activity and climate change. In spite of its important and protected status, fluid flow model of the area, which could support water management and natural protection policy, had not been constructed previously. The 3D

  5. Characteristics of inferior variation of water environment and regulating capacity of groundwater reservoir in Jinghui Canal Irrigation District of China%泾惠渠灌区水环境劣变特征及地下水调蓄能力分析

    Institute of Scientific and Technical Information of China (English)

    刘燕; 朱红艳

    2011-01-01

    为确保泾惠渠灌区水环境安全及地下水资源的可持续开发利用,该文通过对20世纪80年代以来泾惠渠灌区地表水和地下水环境劣变特征分析,重点指出了灌区地下水环境劣变的严重性,同时也证实了对地下水实施涵养调蓄的必要性.从取水条件、地下库容、蓄水水源和蓄水方式4个方面论证了灌区具备良好地下水调蓄能力,并利用体积疏干法对灌区各测站的地下调蓄库容进行计算,确定出灌区最大调蓄库容达6.46亿m3,年调蓄库容0.281亿m3.提出对灌区春、夏两季适当加大地表灌溉力度,并针对调蓄空间较大的石桥、泾阳等站进行优先调蓄,实现灌区“以井补渠,以渠养井”,即涵养了当地地下水资源,又有利于灌区水资源的可持续利用,最终保障了灌区的生态环境及粮食安全.%To ensure the safety of water environment and sustainable utilization of groundwater resource, the severity of inferior variation in Jinghui Canal Irrigation District was pointed out, and the necessity to carry out regulating capacity of groundwater reservior was confirmed by analyzing characteristics of inferior variation of water environment since 1980s. Irrigation district was verified to possess ability for regulating capacity of groundwater reservior by water intaking condition, groundwater reservior, water source for reserve and reserve pattern. The regulating capacity of groundwater reservoir of each observation station was calculated through capacity drainage method, 6.46 X 108m3 could be regarded as the maximal regulating capacity of groundwater reservoir, 0.281 X 108 m3 regulating capacity of groundwater reservoir per year. The results indicated that utilization of surface water should be intensified in Spring and Summer properly, Shiqiao and Jingyang stations should take precedence to reserve groundwater in view of larger regulating capacity of groundwater reservoir and water supply ability, and

  6. Dynamics of Agricultural Groundwater Extraction

    NARCIS (Netherlands)

    Hellegers, P.J.G.J.; Zilberman, D.; Ierland, van E.C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is

  7. Halon-1301, a new Groundwater Age Tracer

    Science.gov (United States)

    Beyer, Monique; van der Raaij, Rob; Morgenstern, Uwe; Jackson, Bethanna

    2015-04-01

    Groundwater dating is an important tool to assess groundwater resources in regards to direction and time scale of groundwater flow and recharge and to assess contamination risks and manage remediation. To infer groundwater age information, a combination of different environmental tracers, such as tritium and SF6, are commonly used. However ambiguous age interpretations are often faced, due to a limited set of available tracers and limitations of each tracer method when applied alone. There is a need for additional, complementary groundwater age tracers. We recently discovered that Halon-1301, a water soluble and entirely anthropogenic gaseous substance, may be a promising candidate [Beyer et al, 2014]. Halon-1301 can be determined along with SF6, SF5CF3 and CFC-12 in groundwater using a gas chromatography setup with attached electron capture detector developed by Busenberg and Plummer [2008]. Halon-1301 has not been assessed in groundwater. This study assesses the behaviour of Halon-1301 in water and its suitability as a groundwater age tracer. We determined Halon-1301 in 17 groundwater and various modern (river) waters sites located in 3 different groundwater systems in the Wellington Region, New Zealand. These waters have been previously dated with tritium, CFC-12, CFC-11 and SF6 with mean residence times ranging from 0.5 to over 100 years. The waters range from oxic to anoxic and some show evidence of CFC contamination or degradation. This allows us to assess the different properties affecting the suitability of Halon-1301 as groundwater age tracer, such as its conservativeness in water and local contamination potential. The samples are analysed for Halon-1301 and SF6simultaneously, which allows identification of issues commonly faced when using gaseous tracers such as contamination with modern air during sampling. Overall we found in the assessed groundwater samples Halon-1301 is a feasible new groundwater tracer. No sample indicated significantly elevated

  8. 电子商务环境下会计系统的设计与实现%The electronic commerce environment accounting system design and implementation

    Institute of Scientific and Technical Information of China (English)

    杨丹

    2016-01-01

    under the environment of e-commerce development, enterprises need to adapt themselves to the accounting system, the electronic commerce development, electronic books and electronic financial statements, etc, for the development of the enterprise accounting system, a greater role, this paper to electronic commerce environment accounting system design and implementation for research purposes, through the concept of e-commerce, accounting system is analyzed, and it is concluded that the demand of the electronic commerce environment accounting system, and realize the design of the electronic commerce environment accounting system, accounting system is better to help the development of electronic commerce.%在电子商务发展的环境下,企业的会计系统需要与之相适应,电子商务发展下,电子账簿、电子财务报表等产生,对企业会计系统的发展,有较大的推动作用,为此本文以电子商务环境下会计系统的设计与实现为研究目的,通过对电子商务、会计系统相关的概念进行分析,进而得出电子商务环境下会计系统的需求,并实现电子商务环境下会计系统的设计,使得会计系统更好的为电子商务的发展提供帮助。

  9. Potential groundwater age tracer found: Halon-1301 (CF3Br), as previously identified as CFC-13 (CF3Cl)

    Science.gov (United States)

    Beyer, Monique; van der Raaij, Rob; Morgenstern, Uwe; Jackson, Bethanna

    2014-09-01

    Groundwater dating using anthropogenic and natural tracer substances is a powerful tool for understanding groundwater dynamics for improved management of groundwater resources. Due to limitations in individual dating methods, often multiple tracers are used to reduce ambiguities. It is commonly accepted that there is a need for further complementary age tracers, in addition to current ones (e.g., tritium, SF6, and CFCs). We propose a potential new groundwater age tracer, Halon-1301 (CF3Br), which can easily be determined using gas chromatography with an attached electron capture detector (GC/ECD) developed by Busenberg and Plummer (2008). Its peak was noted by Busenberg and Plummer (2008), but they believed it to be CFC-13 (CF3Cl) at that time. We performed rigorous tests on gases containing or excluding Halon-1301 and CFC-13 and modern water samples and concluded that the two compounds have extremely similar retention times. Additionally, we found that the ECD response of CFC-13 is far too low to be detected in groundwater or air using standard volumes and sampling techniques. However, the peak areas and concentrations Busenberg and Plummer (2008) reported are in line with what would be expected for Halon-1301. Thus, we are confident that the peak formerly identified as CFC-13 is actually Halon-1301. Busenberg agrees with our findings. We further suggest that Halon-1301 has potential as a (complementary) age tracer, due to its established atmospheric history, and could hypothetically be used to date groundwater recharged in the 1970s or onward. We discuss known relevant properties, such as solubility and stability of Halon-1301 in the context of how these effect its potential application as a groundwater age tracer. Some open questions remain concerning how conservative Halon-1301 is—is it subject to degradation, retardation, and/or local contamination in groundwater. We are confident that Halon-1301 possesses important tracer relevant properties, but further

  10. GIBBS FREE-ENERGY OF FORMATION OF HALOGENATED AROMATIC-COMPOUNDS AND THEIR POTENTIAL ROLE AS ELECTRON-ACCEPTORS IN ANAEROBIC ENVIRONMENTS

    NARCIS (Netherlands)

    DOLFING, J; HARRISON, BK

    1992-01-01

    The Gibbs free energies of formation of various classes of halogenated aromatic compounds were estimated with Benson's method. The data were used to evaluate the potential of these compounds to serve as electron acceptors in anaerobic environments. The results indicate that for (chloro) benzenes, be

  11. The Effect of a Learning Environment Using an Electronic Health Record (EHR) on Undergraduate Nursing Students' Behaviorial Intention to Use an EHR

    Science.gov (United States)

    Foley, Shawn

    2011-01-01

    The purpose of this study was to explore the effect of a learning environment using an Electronic Health Record (EHR) on undergraduate nursing students' behavioral intention (BI) to use an EHR. BI is defined by Davis (1989) in the Technology Acceptance Model (TAM) as the degree to which a person has formulated conscious plans to perform or not…

  12. The Effect of a Learning Environment Using an Electronic Health Record (EHR) on Undergraduate Nursing Students' Behaviorial Intention to Use an EHR

    Science.gov (United States)

    Foley, Shawn

    2011-01-01

    The purpose of this study was to explore the effect of a learning environment using an Electronic Health Record (EHR) on undergraduate nursing students' behavioral intention (BI) to use an EHR. BI is defined by Davis (1989) in the Technology Acceptance Model (TAM) as the degree to which a person has formulated conscious plans to perform or not…

  13. GIBBS FREE-ENERGY OF FORMATION OF HALOGENATED AROMATIC-COMPOUNDS AND THEIR POTENTIAL ROLE AS ELECTRON-ACCEPTORS IN ANAEROBIC ENVIRONMENTS

    NARCIS (Netherlands)

    DOLFING, J; HARRISON, BK

    1992-01-01

    The Gibbs free energies of formation of various classes of halogenated aromatic compounds were estimated with Benson's method. The data were used to evaluate the potential of these compounds to serve as electron acceptors in anaerobic environments. The results indicate that for (chloro) benzenes,

  14. From Physical Benchmarks to Mental Benchmarks: A Four Dimensions Dynamic Model to Assure the Quality of Instructional Activities in Electronic and Virtual Learning Environments

    Science.gov (United States)

    Ahmed Abdelaziz, Hamdy

    2013-01-01

    The objective of this paper was to develop a four dimensions dynamic model for designing instructional activities appropriate to electronic and virtual learning environments. The suggested model is guided by learning principles of cognitivism, constructivism, and connectivism learning theories in order to help online learners to build and acquire…

  15. Human health and groundwater

    Science.gov (United States)

    The high quality of most groundwaters, consequent upon the self-purification capacity of subsurface strata, has long been a key factor in human health and wellbeing. More than 50% of the world’s population now rely on groundwater for their supply of drinking water – and in most circumstances a prope...

  16. Groundwater and Distribution Workbook.

    Science.gov (United States)

    Ekman, John E.

    Presented is a student manual designed for the Wisconsin Vocational, Technical and Adult Education Groundwater and Distribution Training Course. This program introduces waterworks operators-in-training to basic skills and knowledge required for the operation of a groundwater distribution waterworks facility. Arranged according to the general order…

  17. Trends in groundwater quality in relation to groundwater age

    NARCIS (Netherlands)

    Visser, A.

    2009-01-01

    Groundwater is a valuable natural resource and as such should be protected from chemical pollution. Because of the long travel times of pollutants through groundwater bodies, early detection of groundwater quality deterioration is necessary to efficiently protect groundwater bodies. The aim of this

  18. Trends in groundwater quality in relation to groundwater age

    NARCIS (Netherlands)

    Visser, A.

    2009-01-01

    Groundwater is a valuable natural resource and as such should be protected from chemical pollution. Because of the long travel times of pollutants through groundwater bodies, early detection of groundwater quality deterioration is necessary to efficiently protect groundwater bodies. The aim of this

  19. Groundwater system analysis of south Yishu geosyncline

    Institute of Scientific and Technical Information of China (English)

    DAI Chang-lei; CHI Bao-ming; YI Shu-ping; LI Zhi-jun

    2004-01-01

    South Yishu geosyncline is 50 km southeast of Changchun City of Jilin Province, where an aquifer is thick,surface runoff is abundant and it has potential to develop water resources preferably. By means of system analysis, the authors analyse the structural characteristics, I/O characteristics, function characteristics and boundary and environment characteristics of the groundwater system, so as to search for a way of optimizing water resources arrangement and enhancing water resources'bearing capacity. Based on the analysis results, the authors abstract conceptual model and mathematical model of the groundwater system. The simulation results certify and enrich the knowledge about south Yishu geosyncline.

  20. Classification management plan of groundwater quality in Taiwan

    Science.gov (United States)

    Chen, Chun Ming; Chen, Yu Ying; Pan, Shih Cheng; Li, Hui Jun; Hsiao, Fang Ke

    2017-04-01

    Taiwan Environmental Protection Administration has been monitoring regional water quality for 14 years. Since the beginning of 2002 till now, there are 453 regional groundwater monitoring wells in ten groundwater subregions in Taiwan, and the monitoring of groundwater quality has been carried out for a long time. Currently, water quality monitoring project has reached 50 items, while the number of water quality monitoring data has reached more than 20,000. In order to use the monitoring data efficiently, this study constructed the localized groundwater quality indicators of Taiwan. This indicator takes into account the different users' point of view, incorporating the Taiwan groundwater pollution monitoring standards (Category II), irrigation water quality standard and drinking water source water quality standard. 50 items of water quality monitoring projects were simplified and classified. The groundwater quality parameters were divided into five items, such as potability for drinking water, salting, external influence, health influences and toxicity hazard. The weight of the five items of groundwater was calculated comprehensively, and the groundwater quality of each monitoring well was evaluated with three grades of good, ordinary, and poor. According to the monitoring results of the groundwater monitoring wells in October to December of 2016, about 70% of groundwater quality in Taiwan is in good to ordinary grades. The areas with poor groundwater quality were mostly distributed in coastal, agriculture and part of the urban areas. The conductivity or ammonia nitrogen concentration was higher in those regions, showing that groundwater may be salinized or affected by external influences. Groundwater quality indicators can clearly show the current comprehensive situation of the groundwater environment in Taiwan and can be used as a tool for groundwater quality classification management. The indicators can coordinate with the Taiwan land planning policy in the

  1. Y-12 Groundwater Protection Program Groundwater And Surface Water Sampling And Analysis Plan For Calendar Year 2014

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-09-01

    This plan provides a description of the groundwater and surface water quality monitoring activities planned for calendar year (CY) 2014 at the U.S. Department of Energy (DOE) Y-12 National Security Complex (Y-12) that will be managed by the Y-12 Groundwater Protection Program (GWPP). Groundwater and surface water monitoring is performed by the GWPP during CY 2014 to achieve the following goals: 􀁸 to protect the worker, the public, and the environment; 􀁸 to maintain surveillance of existing and potential groundwater contamination sources; 􀁸 to provide for the early detection of groundwater contamination and determine the quality of groundwater and surface water where contaminants are most likely to migrate beyond the Oak Ridge Reservation property line; 􀁸 to identify and characterize long-term trends in groundwater quality at Y-12; and 􀁸 to provide data to support decisions concerning the management and protection of groundwater resources. Groundwater and surface water monitoring will be performed in three hydrogeologic regimes at Y-12.

  2. Global depletion of groundwater resources

    NARCIS (Netherlands)

    Wada, Y.; Beek, L.P.H. van; van Kempen, C.M.; Reckman, J.W.T.M.; Vasak, S.; Bierkens, M.F.P.

    2010-01-01

    In regions with frequent water stress and large aquifer systems groundwater is often used as an additional water source. If groundwater abstraction exceeds the natural groundwater recharge for extensive areas and long times, overexploitation or persistent groundwater depletion occurs. Here we provid

  3. Regional analysis of groundwater nitrate concentrations and trends in Denmark in regard to agricultural influence

    DEFF Research Database (Denmark)

    Hansen, B.; Dalgaard, Tommy; Thorling, L.

    2012-01-01

    The act of balancing between an intensive agriculture with a high potential for nitrate pollution and a drinking water supply almost entirely based on groundwater is a challenge faced by Denmark and similar regions around the globe. Since the 1980s, regulations implemented by Danish farmers have......, with documented positive effects on nature and the environment in Denmark. In groundwater, the upward trend in nitrate concentrations was reversed around 1980, and a larger number of downward nitrate trends were seen in the youngest groundwater compared with the oldest groundwater. However, on average......, approximately 48% of the oxic monitored groundwater has nitrate concentrations above the groundwater and drinking water standards of 50 mg l−1. Furthermore, trend analyses show that 33% of all the monitored groundwater has upward nitrate trends, while only 18% of the youngest groundwater has upward nitrate...

  4. Precipitation Intensity Effects on Groundwater Recharge in the Southwestern United States

    Directory of Open Access Journals (Sweden)

    Brian F. Thomas

    2016-03-01

    Full Text Available Episodic recharge as a result of infrequent, high intensity precipitation events comprises the bulk of groundwater recharge in arid environments. Climate change and shifts in precipitation intensity will affect groundwater continuity, thus altering groundwater recharge. This study aims to identify changes in the ratio of groundwater recharge and precipitation, the R:P ratio, in the arid southwestern United States to characterize observed changes in groundwater recharge attributed to variations in precipitation intensity. Our precipitation metric, precipitation intensity magnification, was used to investigate the relationship between the R:P ratio and precipitation intensity. Our analysis identified significant changes in the R:P ratio concurrent with decreases in precipitation intensity. The results illustrate the importance of precipitation intensity in relation to groundwater recharge in arid regions and provide further insights for groundwater management in nonrenewable groundwater systems and in a changing climate.

  5. Groundwater data network interoperability

    Science.gov (United States)

    Brodaric, Boyan; Booth, Nathaniel; Boisvert, Eric; Lucido, Jessica M.

    2016-01-01

    Water data networks are increasingly being integrated to answer complex scientific questions that often span large geographical areas and cross political borders. Data heterogeneity is a major obstacle that impedes interoperability within and between such networks. It is resolved here for groundwater data at five levels of interoperability, within a Spatial Data Infrastructure architecture. The result is a pair of distinct national groundwater data networks for the United States and Canada, and a combined data network in which they are interoperable. This combined data network enables, for the first time, transparent public access to harmonized groundwater data from both sides of the shared international border.

  6. Study of "management in the electronic environment of electronic document" approach in Canada%加拿大《在电子工作环境中管理电子文件》办法的研究

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    With the development of modern information technology,the number of electronic document is gradually increasing. In the face of users' information demands,scientifically and effectively saving huge lots of electronic document becomes an important task. Canada formulated the"management in the electronic environment of electronic document" for long-term access and protection problems of electronic document. This approach is rich in content,and is a good example of the government management of the electronic document,which has the certain enlightenment function to electronic document management and legislation in our country.%  随着现代信息技术的发展,电子文件的数量逐渐增多。面对日益增加的用户信息需求,科学有效地保存数量巨大的电子文件成为一个重要课题。加拿大针对电子文件长期存取与保护的问题制定了《在电子工作环境中管理电子文件》办法。这一办法内容比较丰富,并且很好地体现了政府对电子文件的管理,对我国电子文件管理和立法具有一定的启示作用。

  7. Characterizing In Situ Uranium and Groundwater Flux

    Science.gov (United States)

    Cho, J.; Newman, M. A.; Stucker, V.; Peacock, A.; Ranville, J.; Cabaniss, S.; Hatfield, K.; Annable, M. D.; Klammler, H.; Perminova, I. V.

    2010-12-01

    The goal of this project is to develop a new sensor that incorporates the field-tested concepts of the passive flux meter to provide direct in situ measures of uranium and groundwater fluxes. The sensor uses two sorbents and resident tracers to measure uranium flux and specific discharge directly; but, sensor principles and design should also apply to fluxes of other radionuclides. Flux measurements will assist with obtaining field-scale quantification of subsurface processes affecting uranium transport (e.g., advection) and transformation (e.g., uranium attenuation) and further advance conceptual and computational models for field scale simulations. Project efforts will expand our current understanding of how field-scale spatial variations in uranium fluxes and those for salient electron donor/acceptors, and groundwater are coupled to spatial variations in measured microbial biomass/community composition, effective field-scale uranium mass balances, attenuation, and stability. The new sensor uses an anion exchange resin to measure uranium fluxes and activated carbon with resident tracers to measure water fluxes. Several anion-exchange resins including Dowex 21K and 21K XLT, Purolite A500, and Lewatit S6328 were tested as sorbents for capturing uranium on the sensor and Lewatit S6328 was determined to be the most effective over the widest pH range. Four branched alcohols proved useful as resident tracers for measuring groundwater flows using activated carbon for both laboratory and field conditions. The flux sensor was redesigned to prevent the discharge of tracers to the environment, and the new design was tested in laboratory box aquifers and the field. Geochemical modeling of equilibrium speciation using Visual Minteq and an up-to-date thermodynamic data base suggested Ca-tricarbonato-uranyl complexes predominate under field conditions, while calculated uranyl ion activities were sensitive to changes in pH, dissolved inorganic carbon (DIC) and alkaline earth

  8. Global change and the groundwater management challenge

    Science.gov (United States)

    Gorelick, Steven M.; Zheng, Chunmiao

    2015-05-01

    With rivers in critical regions already exploited to capacity throughout the world and groundwater overdraft as well as large-scale contamination occurring in many areas, we have entered an era in which multiple simultaneous stresses will drive water management. Increasingly, groundwater resources are taking a more prominent role in providing freshwater supplies. We discuss the competing fresh groundwater needs for human consumption, food production, energy, and the environment, as well as physical hazards, and conflicts due to transboundary overexploitation. During the past 50 years, groundwater management modeling has focused on combining simulation with optimization methods to inspect important problems ranging from contaminant remediation to agricultural irrigation management. The compound challenges now faced by water planners require a new generation of aquifer management models that address the broad impacts of global change on aquifer storage and depletion trajectory management, land subsidence, groundwater-dependent ecosystems, seawater intrusion, anthropogenic and geogenic contamination, supply vulnerability, and long-term sustainability. The scope of research efforts is only beginning to address complex interactions using multiagent system models that are not readily formulated as optimization problems and that consider a suite of human behavioral responses.

  9. Nitrate contamination of groundwater and its countermeasures

    Energy Technology Data Exchange (ETDEWEB)

    Mitamura, Hisayoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    The inevitable increases of food production and energy consumption with an increase in world population become main causes of an increase of nitrate load to the environment. Although nitrogen is essential for the growth of animal and plant as a constituent element of protein, excessive nitrate load to the environment contaminates groundwater resources used as drinking water and leads to seriously adverse effects on the health of man and livestock. In order to clarify the problem of nitrate contamination of groundwater and search a new trend of technology development from the viewpoint of environment remediation and protection, the present paper has reviewed adverse effects of nitrate on human health, the actual state of nitrogen cycle, several kinds of nitrate sources, measures for reducing nitrate level, etc. (author)

  10. Geophysical logging for groundwater investigations in Southern Thailand

    Directory of Open Access Journals (Sweden)

    Phongpiyah Klinmanee

    2012-09-01

    Full Text Available In Thailand the Department of Groundwater Resources is drilling to find vital aquifers. Sometimes groundwater formations cannot be identified clearly during drilling; therefore, geophysical logging was applied after drilling and before casing.The tool used here is measuring nine parameters in one run, natural gamma ray, spontaneous potential, single point resistance, normal resistivity (AM 8’’, 16’’, 32’’, and 64’’, mud temperature and resistivity. Cutting was used to support the geophysical interpretations. In many cases the groundwater bearing zones could be clearly identified. The combination of andthe possibility choosing from nine parameters measured provided the necessary data base to identify groundwater bearingzones in different environments. It has been demonstrated that in different wells different tools are favorable than others.Based on the conclusions of this study geophysical logging in groundwater exploration is recommended as a normalstandard technique that should be applied in every new well drilled.

  11. Distribution of acidic groundwater around quaternary volcanoes in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Asamori, Koichi; Ishimaru, Tsuneari; Iwatsuki, Teruki [Japan Nuclear Cycle Development Inst., Toki, Gifu (Japan). Tono Geoscience Center

    2002-06-01

    One important key issue in the understanding of the long-term stability of the geological environment is the influence of magmatism. In this study, we examined the general spatial distribution of acidic groundwater around Quaternary volcanoes in Japan using a database of groundwater geochemistry. The results may be summarized as follows: Acidic groundwater with pH < 4.8 mainly occur in present volcanic regions and are distributed from several kilometers to about 20 km from Quaternary volcanoes. The pH value of groundwater tends to decrease with increasing distance from a volcano. However, these results may be affected by inhomogeneity of groundwater data distribution and the characteristic activity of each volcano. In order to assess a specific volcanic region, a detailed analysis that considers volcanic activity, using a data set with high spatial density is necessary. (author)

  12. Canada's groundwater resources

    National Research Council Canada - National Science Library

    Rivera, Alfonso

    2014-01-01

    Groundwater is essential for life in arid and semiarid region. It is also important in humid regions, and is one of the fundamental requirements for the maintenance of natural landscapes and aquatic ecosystem...

  13. Groundwater Capture Zones

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Source water protection areas are delineated for each groundwater-based public water supply system using available geologic and hydrogeologic information to...

  14. 40 CFR 257.23 - Ground-water sampling and analysis requirements.

    Science.gov (United States)

    2010-07-01

    ... and analysis requirements. (a) The ground-water monitoring program must include consistent sampling... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water sampling and analysis requirements. 257.23 Section 257.23 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)...

  15. 40 CFR Table 1 to Subpart A of... - Maximum Concentration of Constituents for Groundwater Protection

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Maximum Concentration of Constituents for Groundwater Protection 1 Table 1 to Subpart A of Part 192 Protection of Environment ENVIRONMENTAL... Concentration of Constituents for Groundwater Protection Constituent concentration 1 Maximum Arsenic 0.05 Barium...

  16. Groundwater Profession in Transition: Discovery toAdaptation

    Energy Technology Data Exchange (ETDEWEB)

    Narasimhan, T.N.

    2005-04-04

    Over the past century and half, groundwater has played an important role in the economic prosperity of the United States. The groundwater profession which has contributed to this prosperity has grown through the contributions of the U.S. and State Geological Surveys,academia, and industry. A century ago, the energies of the profession were channeled towards discovering new sources of groundwater in a largely unexplored land, and exploiting the resources for maximum economic benefit. Experience has since revealed that groundwater systems are finite, and are intimately linked to surface water bodies and the biosphere. A consequence is that aggressive exploitation of groundwater can lead to unacceptable environmental degradation and social cost. At present, the groundwater profession is in a state of transition from one of discovery and exploitation, to one of balancing resource development with avoiding unacceptable damage to the environment. This paper outlines the history of the groundwater profession in the United States since the late nineteenth century, and speculates on what may lie ahead in the near future, as the profession makes the transition from discovering new sources of groundwater to one of better understanding and adapting to nature's constraints.

  17. [Risk assessment of quaternary groundwater contamination in Beijing Plain].

    Science.gov (United States)

    Guo, Gao-Xuan; Li, Yu; Xu, Liang; Li, Zhi-Ping; Yang, Qing; Xu, Miao-Juan

    2014-02-01

    Firstly, advances in investigation and evaluation of groundwater pollution in China in the last decade were presented, and several issues in the field which hinder the development of groundwater environment were pointed out. Then, four key concepts in risk assessment of groundwater pollution were briefly described with more emphasis on the difference between groundwater pollution assessment and groundwater quality assessment in this paper. After that, a method on risk assessment of groundwater pollution which included four indicators, the pollution assessment, the quality assessment, the vulnerability and the pollution load of groundwater, was presented based on the regional characteristics of Beijing Plain. Also, AHP and expert scoring method were applied to determine the weight of the four evaluation factors. Finally, the application of this method in Beijing Plain showed the area with high, relative high, medium, relative low and low risk of groundwater contamination was 1 232.1 km2, 699.3 km2, 1 951.4 km, 2 644 km2, and 133.2 km2, respectively. The study results showed that the higher risk in the western region was likely caused by the higher pollution load and its higher vulnerability, while the relatively high risk in the southeast of Beijing plain area, the Tongzhou District, is mainly caused by historical pollution sources.

  18. The Gibbs free energy of formation of halogenated benzenes, benzoates and phenols and their potential role as electron acceptors in anaerobic environments.

    Science.gov (United States)

    Dolfing, Jan; Novak, Igor

    2015-02-01

    The sequence of redox reactions in the natural environment generally follows the electron affinity of the electron acceptors present and can be rationalized by the redox potentials of the appropriate half-reactions. Answering the question how halogenated aromatics fit into this sequence requires information on their Gibbs free energy of formation values. In 1992 Gibbs free energy data for various classes of halogenated aromatic compounds were systematically explored for the first time based on Benson's group contribution method. Since then more accurate quantum chemical calculation methods have become available. Here we use these methods to estimate enthalpy and Gibbs free energy of formation values of all chlorinated and brominated phenols. These data and similar state-of-the-art datasets for halogenated benzenes and benzoates were then used to calculate two-electron redox potentials of halogenated aromatics for standard conditions and for pH 7. The results underline the need to take speciation into consideration when evaluating redox potentials at pH 7 and highlight the fact that halogenated aromatics are excellent electron acceptors in aqueous environments.

  19. Limits to global groundwater consumption

    Science.gov (United States)

    de Graaf, I.; Van Beek, L. P.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.

    2016-12-01

    Groundwater is the largest accessible freshwater resource worldwide and is of critical importance for irrigation, and so for global food security. For many regions of the world where groundwater abstraction exceeds groundwater recharge, persistent groundwater depletion occurs. A direct consequence of depletion is falling groundwater levels, reducing baseflows to rivers, harming ecosystems. Also, pumping costs increase, wells dry up and land subsidence can occur. Water demands are expected to increase further due to growing population, economic development and climate change, posing the urgent question how sustainable current water abstractions are worldwide and where and when these abstractions approach conceivable limits with all the associated problems. Here, we estimated past and future trends (1960-2050) in groundwater levels resulting from changes in abstractions and climate and predicted when limits of groundwater consumption are reached. We explored these limits by predicting where and when groundwater levels drop that low that groundwater becomes unattainable for abstractions and how river flows are affected. Water availabilities, abstractions, and lateral groundwater flows are simulated (5 arcmin. resolution) using a coupled version of the global hydrological model PCR-GLOBWB and a groundwater model based on MODFLOW. The groundwater model includes a parameterization of the worlds confined and unconfined aquifer systems, needed for a realistic simulation of groundwater head dynamics. Results show that, next to the existing regions experiencing groundwater depletion (like India, Pakistan, Central Valley) new regions will develop, e.g. Southern Europe, the Middle East, and Africa. Using a limit that reflects present-day feasibility of groundwater abstraction, we estimate that in 2050 groundwater becomes unattainable for 20% of the global population, mainly in the developing countries and pumping cost will increase significantly. Largest impacts are found

  20. Analytical electron microscopy study of new class material Cr2AlC for coating applications at high temperature environments

    Science.gov (United States)

    Iskandar, R.

    2017-04-01

    The interactions between electron and specimens produce wide range of secondary signals from the specimen that can be used in analytical electron microscopy. These signals will give us chemical information and electronic structure information of specimen atoms. Two techniques which based on these secondary signals, X-rays energy-dispersive spectroscopy (XEDS) and electron energy-loss spectroscopy (EELS), are very powerful to be used for characterization materials. These two techniques are complementary each on the other. The former is very useful to quantify heavy elements and the other is very suitable to identify light elements as oxygen and carbon. In this report, we demonstrated the capability of these techniques to investigate microstructure evolution during the oxidation process of thin film Cr2AlC at 1320 °C. This thin film belongs to MAX phase, a new class material, and becomes a promising candidate for coating applications since it exhibits a good oxidation resistant.

  1. A Motor Drive Electronics Assembly for Mars Curiosity Rover: An Example of Assembly Qualification for Extreme Environments

    Science.gov (United States)

    Kolawa, Elizabeth; Chen, Yuan; Mojarradi, Mohammad M.; Tudryn Weber, Carissa

    2013-01-01

    In this paper, the technology development and infusion of the motor drive electronics assembly, along with the technology qualification and space qualification, is described and detailed. The process is an example of the qualification methodology for extreme environmen

  2. Assessment of agricultural groundwater users in Iran: a cultural environmental bias

    Science.gov (United States)

    Salehi, Saeid; Chizari, Mohammad; Sadighi, Hassan; Bijani, Masoud

    2017-08-01

    Many environmental problems are rooted in human behavior. This study aimed to explore the causal effect of cultural environmental bias on `sustainable behavior' among agricultural groundwater users in Fars province, Iran, according to Klockner's comprehensive model. A survey-based research project was conducted to gathering data on the paradigm of environmental psychology. The sample included agricultural groundwater users (n = 296) who were selected at random within a structured sampling regime involving study areas that represent three (higher, medium and lower) bounds of the agricultural-groundwater-vulnerability spectrum. Results showed that the "environment as ductile (EnAD)" variable was a strong determinant of sustainable behavior as it related to groundwater use, and that EnAE had the highest causal effect on the behavior of agricultural groundwater users. The adjusted model explained 41% variance of "groundwater sustainable behavior". Based on the results, the groundwater sustainable behaviors of agricultural groundwater users were found to be affected by personal and subjective norm variables and that they are influenced by casual effects of the "environment as ductile (EnAD)" variable. The conclusions reflect the Fars agricultural groundwater users' attitude or worldview on groundwater as an unrecoverable resource; thus, it is necessary that scientific disciplines like hydrogeology and psycho-sociology be considered together in a comprehensive approach for every groundwater study.

  3. Limits to Global Groundwater Consumption

    Science.gov (United States)

    Graaf, I. D.; Van Beek, R.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.

    2015-12-01

    In regions with frequent water stress and large aquifer systems, groundwater is often used as an additional fresh water source. For many regions of the world groundwater abstraction exceeds groundwater recharge and persistent groundwater depletion occurs. The most direct effect of groundwater depletion is declining of water tables, leading to reduced groundwater discharge needed to sustain base-flow to e.g. rivers. Next to that, pumping costs increase, wells dry up and land subsidence occurs. These problems are expected to increase in the near future due to growing population and climate changes. This poses the urgent question of what the limits are of groundwater consumption worldwide. We simulate global water availability (5 arc-minute resolution, for 1960-2050) using the hydrological model PCR-GLOBWB (van Beek et al. 2011), coupled to a groundwater model based on MODFLOW (de Graaf et al. 2015), allowing for groundwater - surface water interactions. The groundwater model includes a parameterization of world's confined and unconfined aquifer systems needed for a realistic simulation of groundwater head dynamics. Water demands are included (from Wada et al. 2014). We study the limits to water consumption, focusing on locally attainable groundwater and groundwater levels critical to rivers to sustain low flows. We show an increasing trend (1960-2050) in groundwater head declines, due to increase in groundwater demand. Also, stream flow will decrease and low flow conditions will occur more frequent and will be longer in duration in the near future, especially for irrigated areas. Next to that, we provide a global overview of the years it takes until groundwater gets unattainable for e.g. a local farmer (100 m below land-surface used as a proxy), and estimate the increase in pumping cost for the near future. The results show where and when limits of groundwater consumption are reached globally.

  4. Hydrogeochemical characteristics of groundwater depression cones in Yinchuan City, Northwest China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Groundwater in Yinchuan City has been heavily over-exploited, thus leading to the formation of depression cones in confined and phreatic groundwater environments. The depression cones have an important influence on the hydrodynamic and hydrochemical fields of groundwaters. The evolution of depression cones was analyzed on the basis of the monitoring data on groundwater level accumulated in the past 14 years. The ratio of rCl-/rCa2+ showed that phreatic water circulation was intensified, and confined groundwater was affected by external factors. Mass balance of Cl- showed confined water mixed with about 11% phreatic water. It is shown that the alternative function of confined water was affected by external factors. At last, the evolution of groundwater hydrochemical field on the basis of groundwater chemical composition showed that phreatic water quality has been improved whereas confined water quality has been deteriorated. Saturation indices of minerals with respect to phreatic and confined waters were calculated by using PHREEQC.

  5. DS796 California Groundwater Units

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The California Groundwater Units dataset classifies and delineates the State into one of three groundwater based polygon units: (1) those areas defined as alluvial...

  6. Establishment and metabolic analysis of a model microbial community for understanding trophic and electron accepting interactions of subsurface anaerobic environments

    Directory of Open Access Journals (Sweden)

    Yang Zamin K

    2010-05-01

    Full Text Available Abstract Background Communities of microorganisms control the rates of key biogeochemical cycles, and are important for biotechnology, bioremediation, and industrial microbiological processes. For this reason, we constructed a model microbial community comprised of three species dependent on trophic interactions. The three species microbial community was comprised of Clostridium cellulolyticum, Desulfovibrio vulgaris Hildenborough, and Geobacter sulfurreducens and was grown under continuous culture conditions. Cellobiose served as the carbon and energy source for C. cellulolyticum, whereas D. vulgaris and G. sulfurreducens derived carbon and energy from the metabolic products of cellobiose fermentation and were provided with sulfate and fumarate respectively as electron acceptors. Results qPCR monitoring of the culture revealed C. cellulolyticum to be dominant as expected and confirmed the presence of D. vulgaris and G. sulfurreducens. Proposed metabolic modeling of carbon and electron flow of the three-species community indicated that the growth of C. cellulolyticum and D. vulgaris were electron donor limited whereas G. sulfurreducens was electron acceptor limited. Conclusions The results demonstrate that C. cellulolyticum, D. vulgaris, and G. sulfurreducens can be grown in coculture in a continuous culture system in which D. vulgaris and G. sulfurreducens are dependent upon the metabolic byproducts of C. cellulolyticum for nutrients. This represents a step towards developing a tractable model ecosystem comprised of members representing the functional groups of a trophic network.

  7. Teaching Sustainable Energy and Power Electronics to Engineering Students in a Laboratory Environment Using Industry-Standard Tools

    Science.gov (United States)

    Ochs, David S.; Miller, Ruth Douglas

    2015-01-01

    Power electronics and renewable energy are two important topics for today's power engineering students. In many cases, the two topics are inextricably intertwined. As the renewable energy sector grows, the need for engineers qualified to design such systems grows as well. In order to train such engineers, new courses are needed that highlight the…

  8. Groundwater: A Community Action Guide.

    Science.gov (United States)

    Boyd, Susan, Ed.; And Others

    Designed to be a guide for community action, this booklet examines issues and trends related to groundwater contamination. Basic concepts about groundwater and information about problems affecting it are covered under the categories of (1) what is groundwater? (2) availability and depletion; (3) quality and contamination; (4) public health…

  9. Groundwater: A Community Action Guide.

    Science.gov (United States)

    Boyd, Susan, Ed.; And Others

    Designed to be a guide for community action, this booklet examines issues and trends related to groundwater contamination. Basic concepts about groundwater and information about problems affecting it are covered under the categories of (1) what is groundwater? (2) availability and depletion; (3) quality and contamination; (4) public health…

  10. Groundwater quality assessment for the Chestnut Ridge Hydrogeologic Regime at the Y-12 Plant. 1991 groundwater quality data and calculated rate of contaminant migration

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    This report contains groundwater quality data obtained during the 1991 calendar year at several hazardous and non-hazardous waste- management facilities associated with the US Department of Energy (DOE) Y-12 Plant (Figure 1). These sites are located south of the Y-12 Plant in the Chestnut Ridge Hydrogeologic Regime (CRHR), which is one of the three regimes defined for the purposes of groundwater quality monitoring and remediation (Figure 2). The Health, Safety, Environment, and Accountability (HSEA) Division of the Y-12 Plant Environmental Management Department manages the groundwater monitoring activities in each regime as part of the Y-12 Plant Groundwater Protection Program (GWPP).

  11. Brookhaven National Laboratory 2008 Site Environment Report Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Brookhaven National Laboratory

    2009-10-01

    Brookhaven National Laboratory (BNL) prepares an annual Site Environmental Report (SER) in accordance with DOE Order 231.1A, Environment, Safety and Health Reporting of the U.S. Department of Energy. The report is written to inform the public, regulators, employees, and other stakeholders of the Laboratory's environmental performance during the calendar year in review. Volume I of the SER summarizes environmental data; environmental management performance; compliance with applicable DOE, federal, state, and local regulations; and performance in restoration and surveillance monitoring programs. BNL has prepared annual SERs since 1971 and has documented nearly all of its environmental history since the Laboratory's inception in 1947. Volume II of the SER, the Groundwater Status Report, also is prepared annually to report on the status of and evaluate the performance of groundwater treatment systems at the Laboratory. Volume II includes detailed technical summaries of groundwater data and its interpretation, and is intended for internal BNL users, regulators, and other technically oriented stakeholders. A brief summary of the information contained in Volume II is included in this volume in Chapter 7, Groundwater Protection. Both reports are available in print and as downloadable files on the BNL web page at http://www.bnl.gov/ewms/ser/. An electronic version on compact disc is distributed with each printed report. In addition, a summary of Volume I is prepared each year to provide a general overview of the report, and is distributed with a compact disc containing the full report.

  12. Natural radioactivity in groundwater--a review.

    Science.gov (United States)

    Dinh Chau, Nguyen; Dulinski, Marek; Jodlowski, Pawel; Nowak, Jakub; Rozanski, Kazimierz; Sleziak, Monika; Wachniew, Przemyslaw

    2011-12-01

    The issue of natural radioactivity in groundwater is reviewed, with emphasis on those radioisotopes which contribute in a significant way to the overall effective dose received by members of the public due to the intake of drinking water originating from groundwater systems. The term 'natural radioactivity' is used in this context to cover all radioactivity present in the environment, including man-made (anthropogenic) radioactivity. Comprehensive discussion of radiological aspects of the presence of natural radionuclides in groundwater, including an overview of current regulations dealing with radioactivity in drinking water, is provided. The presented data indicate that thorough assessments of the committed doses resulting from the presence of natural radioactivity in groundwater are needed, particularly when such water is envisaged for regular intake by infants. They should be based on a precise determination of radioactivity concentration levels of the whole suite of radionuclides, including characterisation of their temporal variability. Equally important is a realistic assessment of water intake values for specific age groups. Only such an evaluation may provide the basis for possible remedial actions.

  13. Eddy correlation measurements of submarine groundwater discharge

    Science.gov (United States)

    Crusius, J.; Berg, P.; Koopmans, D.J.; Erban, L.

    2008-01-01

    This paper presents a new, non-invasive means of quantifying groundwater discharge into marine waters using an eddy correlation approach. The method takes advantage of the fact that, in virtually all aquatic environments, the dominant mode of vertical transport near the sediment-water interface is turbulent mixing. The technique thus relies on measuring simultaneously the fluctuating vertical velocity using an acoustic Doppler velocimeter and the fluctuating salinity and/or temperature using rapid-response conductivity and/or temperature sensors. The measurements are typically done at a height of 5-15??cm above the sediment surface, at a frequency of 16 to 64??Hz, and for a period of 15 to 60??min. If the groundwater salinity and/or temperature differ from that of the water column, the groundwater specific discharge (cm d- 1) can be quantified from either a heat or salt balance. Groundwater discharge was estimated with this new approach in Salt Pond, a small estuary on Cape Cod (MA, USA). Estimates agreed well with previous estimates of discharge measured using seepage meters and 222Rn as a tracer. The eddy correlation technique has several desirable characteristics: 1) discharge is quantified under in-situ hydrodynamic conditions; 2) salinity and temperature can serve as two semi-independent tracers of discharge; 3) discharge can be quantified at high temporal resolution, and 4) long-term records of discharge may be possible, due to the low power requirements of the instrumentation. ?? 2007 Elsevier B.V. All rights reserved.

  14. ELECTRON-CAPTURE AND β-DECAY RATES FOR sd-SHELL NUCLEI IN STELLAR ENVIRONMENTS RELEVANT TO HIGH-DENSITY O–NE–MG CORES

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Toshio [Department of Physics and Graduate School of Integrated Basic Sciences, College of Humanities and Sciences, Nihon University Sakurajosui 3-25-40, Setagaya-ku, Tokyo 156-8550 (Japan); Toki, Hiroshi [Research Center for Nuclear Physics (RCNP), Osaka University, Ibaraki, Osaka 567-0047 (Japan); Nomoto, Ken’ichi, E-mail: suzuki@phys.chs.nihon-u.ac.jp [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, Kashiwa, Chiba 277-8583 (Japan)

    2016-02-01

    Electron-capture and β-decay rates for nuclear pairs in the sd-shell are evaluated at high densities and high temperatures relevant to the final evolution of electron-degenerate O–Ne–Mg cores of stars with initial masses of 8–10 M{sub ⊙}. Electron capture induces a rapid contraction of the electron-degenerate O–Ne–Mg core. The outcome of rapid contraction depends on the evolutionary changes in the central density and temperature, which are determined by the competing processes of contraction, cooling, and heating. The fate of the stars is determined by these competitions, whether they end up with electron-capture supernovae or Fe core-collapse supernovae. Since the competing processes are induced by electron capture and β-decay, the accurate weak rates are crucially important. The rates are obtained for pairs with A = 20, 23, 24, 25, and 27 by shell-model calculations in the sd-shell with the USDB Hamiltonian. Effects of Coulomb corrections on the rates are evaluated. The rates for pairs with A = 23 and 25 are important for nuclear Urca processes that determine the cooling rate of the O–Ne–Mg core, while those for pairs with A = 20 and 24 are important for the core contraction and heat generation rates in the core. We provide these nuclear rates at stellar environments in tables with fine enough meshes at various densities and temperatures for studies of astrophysical processes sensitive to the rates. In particular, the accurate rate tables are crucially important for the final fates of not only O–Ne–Mg cores but also a wider range of stars, such as C–O cores of lower-mass stars.

  15. Nuclear and Non-Ionizing Energy-loss of Electrons with Low and Relativistic Energies in Materials and Space Environment

    CERN Document Server

    Boschini, M.J.

    2012-01-01

    The treatment of the electron-nucleus interaction based on the Mott differential cross section was extended to account for effects due to screened Coulomb potentials, finite sizes and finite rest masses of nuclei for electrons above 200 keV and up to ultra high energies. This treatment allows one to determine both the total and differential cross sections, thus, subsequently to calculate the resulting nuclear and non-ionizing stopping powers. Above a few hundreds of MeV, neglecting the effect due to finite rest masses of recoil nuclei the stopping power and NIEL result to be largely underestimated; while, above a few tens of MeV the finite size of the nuclear target prevents a further large increase of stopping powers which approach almost constant values.

  16. Effects of water-sediment interaction and irrigation practices on iodine enrichment in shallow groundwater

    Science.gov (United States)

    Li, Junxia; Wang, Yanxin; Xie, Xianjun; DePaolo, Donald J.

    2016-12-01

    High iodine concentrations in groundwater have caused serious health problems to the local residents in the Datong basin, northern China. To determine the impact of water-sediment interaction and irrigation practices on iodine mobilization in aquifers, isotope (2H, 18O and 87Sr/86Sr) and hydrogeochemical studies were conducted. The results show that groundwater iodine concentrations vary from 14.4 to 2180 μg/L, and high iodine groundwater (>150 μg/L) mainly occurs in the central area of the Datong basin. Sediment iodine content is between organic matter acts as the main source of groundwater iodine. The 87Sr/86Sr values and groundwater chemistry suggest that aluminosilicate hydrolysis is the dominant process controlling hydrochemical evolution along groundwater flowpath, and the degradation of TOC/iodine-rich sediment mediated by microbes potentially triggers the iodine release from the sediment into groundwater in the discharge area. The vertical stratification of groundwater 18O and 2H isotope reflects the occurrence of a vertical mixing process driven by periodic surface irrigation. The vertical mixing could change the redox potential of shallow groundwater from sub-reducing to oxidizing condition, thereby affecting the iodine mobilization in shallow groundwater. It is postulated that the extra introduction of organic matter and O2/NO3/SO4 could accelerate the microbial activity due to the supplement of high ranking electron acceptors and promote the iodine release from the sediment into shallow groundwater.

  17. Assessment of TVOC and Odor in the Remediation Site of Contaminated Soil and Groundwater Using Electronic Nose%基于电子鼻土壤与地下水污染修复现场TVOC和恶臭的评估

    Institute of Scientific and Technical Information of China (English)

    田秀英; 蔡强; 刘锐; 张永明

    2013-01-01

    According to the conditions of a contaminated soil and groundwater remediation site in Shanghai, the self-built electronic nose was applied to detect VOCs and odor of previously remedied soil and groundwater, remedying soil and groundwater, and the air above and around the site. Combining the formula of TPI and OPI, the value of each point was got and was shown in figures. Results showed:① Comparing the determination results of previously remedied with remedying contaminated soil and groundwater, the concentration of TVOC and odor was overall declined. The result was consistent with the fact. The detection result of electronic nose was proved to be right; ② In the remediation process of soil and groundwater, the volatilization of VOCs and odor was inflected by temperature and works of crushing, adding medicine and turning the soil on time. The concentration showed a trend of overall decline with stage rising, so the electronic noses can be used for dynamic monitoring of the whole remediation process; ③ Combined with the GIS, the electronic noses can preliminary assess space pollution situation caused by the remediation of contaminated soil and groundwater and the influence on the residence in the surrounding region. However, further study on the refined classification of the impact degree is needed.%根据上海某土壤与地下水污染修复现场情况,应用自主研发的电子鼻系统(iSA-M1)分别对未修复及修复过程中的土壤和地下水、修复场地上空及周边空气中的VOCs和恶臭类气体进行检测.结合前期研究所得TPI和OPI公式,求得各点的值,并将其用图表示.结果表明:①修复后TVOC和恶臭的浓度总体呈下降趋势;②在土壤和地下水修复过程中,VOCs和恶臭的挥发受气象要素和作业的影响,其浓度在总体下降的过程中伴随着阶段性上升现象;③结合GIS技术,电子鼻能初步用于评估土壤和地下水修复现场造成的空间污染情况及对周围

  18. Isotopic evidence for a link between agricultural irrigation and high arsenic concentrations in groundwater

    Science.gov (United States)

    Li, M.; Wang, Y.; Shock, E.

    2011-12-01

    An isotope-based survey was carried out in the Datong Basin, northern China to investigate the hydrogeology of groundwater with high arsenic concentrations. Oxygen isotope (δ18O), hydrogen isotope (δD) and radioactive hydrogen isotope (3H) measurements were conducted with the aim of characterizing the groundwater origins and flow dynamics in this arsenic-contaminated groundwater system. Groundwater dating results from 3H measurements show that groundwaters from 20m ~ 70m have a wide range of ages (10a~ 191a), indicating diverse groundwater sources. In contrast, deeper groundwaters (70m ~90m) display a narrower age range (35a ~ 47a). In addition, the shallow-aquifer (70m) possess relatively narrower isotopic ranges and mostly lighter isotopic ratios, from -12.8% to -8.88% and -97.6% to -71.7%, respectively. Comparison with the local meteoric water line shows that groundwater δ18O and δD values plot with a shallower slope, consistent with the arid-semiarid climate of the Datong Basin, as well as a meteoric origin of the groundwater, and points to precipitation as the dominant source of recharge to the deeper aquifers in the study area. Groundwaters with high arsenic concentrations (100μg/L ~ 309μg/L) mainly occur in aquifers at depths between 20m and 70m, while shallower (70m) groundwaters carry relatively lower arsenic concentrations (Science of the Total Environment 407(12): 3823-3835.

  19. Phase-Space Density Analysis of the AE-8 Traped Electron and the AP-8 Trapped Proton Model Environments

    Energy Technology Data Exchange (ETDEWEB)

    Thomas E. Cayton

    2005-08-01

    The AE-8 trapped electron and the AP-8 trapped proton models are used to examine the L-shell variation of phase-space densities for sets of transverse (or 1st) invariants, {mu}, and geometrical invariants, K (related to the first two adiabatic invariants). The motivation for this study is twofold: first, to discover the functional dependence of the phase-space density upon the invariants; and, second, to explore the global structure of the radiation belts within this context. Variation due to particle rest mass is considered as well. The overall goal of this work is to provide a framework for analyzing energetic particle data collected by instruments on Global Positioning System (GPS) spacecraft that fly through the most intense region of the radiation belt. For all considered values of {mu} and K, and for 3.5 R{sub E} < L < 6.5 R{sub E}, the AE-8 electron phase-space density increases with increasing L; this trend--the expected one for a population diffusing inward from an external source--continues to L = 7.5 R{sub E} for both small and large values of K but reverses slightly for intermediate values of K. The AP-8 proton phase-space density exhibits {mu}-dependent local minima around L = 5 R{sub E}. Both AE-8 and AP-8 exhibit critical or cutoff values for the invariants beyond which the flux and therefore the phase-space density vanish. For both electrons and protons, these cutoff values vary systematically with magnetic moment and L-shell and are smaller than those estimated for the atmospheric loss cone. For large magnetic moments, for both electrons and protons, the K-dependence of the phase-space density is exponential, with maxima at the magnetic equator (K = 0) and vanishing beyond a cutoff value, K{sub c}. Such features suggest that momentum-dependent trapping boundaries, perhaps drift-type loss cones, serve as boundary conditions for trapped electrons as well as trapped protons.

  20. Phase-Space Density Analyses of the AE-8 Trapped Electron and the AP-8 Trapped Proton Model Environments

    Energy Technology Data Exchange (ETDEWEB)

    T.E. Cayton

    2005-08-12

    The AE-8 trapped electron and the AP-8 trapped proton models are used to examine the L-shell variation of phase-space densities for sets of transverse (or 1st) invariants, {mu}, and geometrical invariants, K (related to the first two adiabatic invariants). The motivation for this study is twofold: first, to discover the functional dependence of the phase-space density upon the invariants; and, second, to explore the global structure of the radiation belts within this context. Variation due to particle rest mass is considered as well. The overall goal of this work is to provide a framework for analyzing energetic particle data collected by instruments on Global Positioning System (GPS) spacecraft that fly through the most intense region of the radiation belt. For all considered values of {mu} and K, and for 3.5 R{sub E} < L < 6.5 R{sub E}, the AE-8 electron phase-space density increases with increasing L; this trend--the expected one for a population diffusing inward from an external source--continues to L = 7.5 R{sub E} for both small and large values of K but reverses slightly for intermediate values of K. The AP-8 proton phase-space density exhibits {mu}-dependent local minima around L = 5 R{sub E}. Both AE-8 and AP-8 exhibit critical or cutoff values for the invariants beyond which the flux and therefore the phase-space density vanish. For both electrons and protons, these cutoff values vary systematically with magnetic moment and L-shell and are smaller than those estimated for the atmospheric loss cone. For large magnetic moments, for both electrons and protons, the K-dependence of the phase-space density is exponential, with maxima at the magnetic equator (K = 0) and vanishing beyond a cutoff value, K{sub c}. Such features suggest that momentum-dependent trapping boundaries, perhaps drift-type loss cones, serve as boundary conditions for trapped electrons as well as trapped protons.

  1. In vitro growth environment produces lipidomic and electron transport chain abnormalities in mitochondria from non-tumorigenic astrocytes and brain tumours

    Directory of Open Access Journals (Sweden)

    Thomas N Seyfried

    2009-05-01

    Full Text Available The mitochondrial lipidome influences ETC (electron transport chain and cellular bioenergetic efficiency. Brain tumours are largely dependent on glycolysis for energy due to defects in mitochondria and oxidative phosphorylation. In the present study, we used shotgun lipidomics to compare the lipidome in highly purified mitochondria isolated from normal brain, from brain tumour tissue, from cultured tumour cells and from non-tumorigenic astrocytes. The tumours included the CT-2A astrocytoma and an EPEN (ependymoblastoma, both syngeneic with the C57BL/6J (B6 mouse strain. The mitochondrial lipidome in cultured CT-2A and EPEN tumour cells were compared with those in cultured astrocytes and in solid tumours grown in vivo. Major differences were found between normal tissue and tumour tissue and between in vivo and in vitro growth environments for the content or composition of ethanolamine glycerophospholipids, phosphatidylglycerol and cardiolipin. The mitochondrial lipid abnormalities in solid tumours and in cultured cells were associated with reductions in multiple ETC activities, especially Complex I. The in vitro growth environment produced lipid and ETC abnormalities in cultured non-tumorigenic astrocytes that were similar to those associated with tumorigenicity. It appears that the culture environment obscures the boundaries of the Crabtree and the Warburg effects. These results indicate that in vitro growth environments can produce abnormalities in mitochondrial lipids and ETC activities, thus contributing to a dependency on glycolysis for ATP production.

  2. PATHS groundwater hydrologic model

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, R.W.; Schur, J.A.

    1980-04-01

    A preliminary evaluation capability for two-dimensional groundwater pollution problems was developed as part of the Transport Modeling Task for the Waste Isolation Safety Assessment Program (WISAP). Our approach was to use the data limitations as a guide in setting the level of modeling detail. PATHS Groundwater Hydrologic Model is the first level (simplest) idealized hybrid analytical/numerical model for two-dimensional, saturated groundwater flow and single component transport; homogeneous geology. This document consists of the description of the PATHS groundwater hydrologic model. The preliminary evaluation capability prepared for WISAP, including the enhancements that were made because of the authors' experience using the earlier capability is described. Appendixes A through D supplement the report as follows: complete derivations of the background equations are provided in Appendix A. Appendix B is a comprehensive set of instructions for users of PATHS. It is written for users who have little or no experience with computers. Appendix C is for the programmer. It contains information on how input parameters are passed between programs in the system. It also contains program listings and test case listing. Appendix D is a definition of terms.

  3. Regulating groundwater use

    NARCIS (Netherlands)

    Hoogesteger van Dijk, Jaime; Wester, Flip

    2017-01-01

    Around the world it has proven very difficult to develop policies and interventions that ensure socio-environmentally sustainable groundwater use and exploitation. In the state of Guanajuato, Central Mexico, both the national government and the decentralized state government have pursued to regulate

  4. Calculation of electron dose to target cells in a complex environment by Monte Carlo code ''CELLDOSE''

    Energy Technology Data Exchange (ETDEWEB)

    Hindie, Elif; Moretti, Jean-Luc [Hopital Saint-Louis, Service de Medecine Nucleaire, Paris (France)]|[Universite Paris 7, Imagerie Moleculaire Diagnostique et Ciblage Therapeutique, Paris (France); Champion, Christophe [Universite Paul Verlaine, Laboratoire de Physique Moleculaire et des Collisions, Metz Institut de Physique, Metz (France); Zanotti-Fregonara, Paolo; Ravasi, Laura [Commissariat a l' Energie Atomique, DSV/I2BM/SHFJ/LIME, Orsay (France); Rubello, Domenico [Instituto Oncologico Veneto (IOV) - IRCCS, Department of Nuclear Medicine - PET Centre, Rovigo (Italy); Colas-Linhart, Nicole [Faculte de Medecine Xavier Bichat, Laboratoire de Biophysique, Paris (France)

    2009-01-15

    We used the Monte Carlo code ''CELLDOSE'' to assess the dose received by specific target cells from electron emissions in a complex environment. {sup 131}I in a simulated thyroid was used as a model. Thyroid follicles were represented by 170{mu}m diameter spherical units made of a lumen of 150{mu}m diameter containing colloidal matter and a peripheral layer of 10{mu}m thick thyroid cells. Neighbouring follicles are 4{mu}m apart. {sup 131}I was assumed to be homogeneously distributed in the lumen and absent in cells. We firstly assessed electron dose distribution in a single follicle. Then, we expanded the simulation by progressively adding neighbouring layers of follicles, so to reassess the electron dose to this single follicle implemented with the contribution of the added layers. Electron dose gradient around a point source showed that the {sup 131}I electron dose is close to zero after 2,100{mu}m. Therefore, we studied all contributions to the central follicle deriving from follicles within 12 orders of neighbourhood (15,624 follicles surrounding the central follicle). The dose to colloid of the single follicle was twice as high as the dose to thyroid cells. Even when all neighbours were taken into account, the dose in the central follicle remained heterogeneous. For a 1-Gy average dose to tissue, the dose to colloidal matter was 1.168 Gy, the dose to thyroid cells was 0.982 Gy, and the dose to the inter-follicular tissue was 0.895 Gy. Analysis of the different contributions to thyroid cell dose showed that 17.3% of the dose derived from the colloidal matter of their own follicle, while the remaining 82.7% was delivered by the surrounding follicles. On the basis of these data, it is shown that when different follicles contain different concentrations of {sup 131}I, the impact in terms of cell dose heterogeneity can be important. By means of {sup 131}I in the thyroid as a theoretical model, we showed how a Monte Carlo code can be used to map

  5. A Multi-Methodology for improving Adelaide's Groundwater Management

    Science.gov (United States)

    Batelaan, Okke; Banks, Eddie; Batlle-Aguilar, Jordi; Breciani, Etienne; Cook, Peter; Cranswick, Roger; Smith, Stan; Turnadge, Chris; Partington, Daniel; Post, Vincent; Pool Ramirez, Maria; Werner, Adrian; Xie, Yueqing; Yang, Yuting

    2015-04-01

    Groundwater is a strategic and vital resource in South Australia playing a crucial role in sustaining a healthy environment, as well as supporting industries and economic development. In the Adelaide metropolitan region ten different aquifer units have been identified, extending to more than 500 m below sea level. Although salinity within most of these aquifers is variable, water suitable for commercial, irrigation and/or potable use is predominantly found in the deeper Tertiary aquifers. Groundwater currently contributes only 9000 ML/yr of Adelaide's total water consumption of 216,000 ML, while in the Northern Adelaide Plains 17000 ML/yr is used. However, major industries, market gardeners, golf courses, and local councils are highly dependent on this resource. Despite recent rapid expansion in managed aquifer recharge, and the potential for increased extraction of groundwater, particularly for the commercial and irrigation supplies, little is known about the sources and ages of Adelaide's groundwater. The aim of this study is therefore to provide a robust conceptualisation of Adelaide's groundwater system. The study focuses on three important knowledge gaps: 1. Does groundwater flow from the Adelaide Hills into the sedimentary aquifers on the plains? 2. What is the potential for encroachment of seawater if groundwater extraction increases? 3. How isolated are the different aquifers, or does water leak from one to the other? A multi-tool approach has been used to improve the conceptual understanding of groundwater flow processes; including the installation of new groundwater monitoring wells from the hills to the coast, an extensive groundwater sampling campaign of new and existing groundwater wells for chemistry and environmental tracers analysis, and development of a regional scale numerical model rigorously tested under different scenario conditions. The model allows quantification of otherwise hardly quantifiable quantities such as flow across fault zones and

  6. Influence of environment induced correlated fluctuations in electronic coupling on coherent excitation energy transfer dynamics in model photosynthetic systems.

    Science.gov (United States)

    Huo, Pengfei; Coker, David F

    2012-03-21

    Two-dimensional photon-echo experiments indicate that excitation energy transfer between chromophores near the reaction center of the photosynthetic purple bacterium Rhodobacter sphaeroides occurs coherently with decoherence times of hundreds of femtoseconds, comparable to the energy transfer time scale in these systems. The original explanation of this observation suggested that correlated fluctuations in chromophore excitation energies, driven by large scale protein motions could result in long lived coherent energy transfer dynamics. However, no significant site energy correlation has been found in recent molecular dynamics simulations of several model light harvesting systems. Instead, there is evidence of correlated fluctuations in site energy-electronic coupling and electronic coupling-electronic coupling. The roles of these different types of correlations in excitation energy transfer dynamics are not yet thoroughly understood, though the effects of site energy correlations have been well studied. In this paper, we introduce several general models that can realistically describe the effects of various types of correlated fluctuations in chromophore properties and systematically study the behavior of these models using general methods for treating dissipative quantum dynamics in complex multi-chromophore systems. The effects of correlation between site energy and inter-site electronic couplings are explored in a two state model of excitation energy transfer between the accessory bacteriochlorophyll and bacteriopheophytin in a reaction center system and we find that these types of correlated fluctuations can enhance or suppress coherence and transfer rate simultaneously. In contrast, models for correlated fluctuations in chromophore excitation energies show enhanced coherent dynamics but necessarily show decrease in excitation energy transfer rate accompanying such coherence enhancement. Finally, for a three state model of the Fenna-Matthews-Olsen light

  7. Waste Isolation Pilot Plant Groundwater Protection Management Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    The DOE has mandated in DOE Order 5400.1 that its operations will be conducted in an environmentally safe manner. The Waste Isolation Pilot Plant (WIPP) will comply with DOE Order 5400.1 and will conduct its operations in a manner that ensures the safety of the environment and the public. This document outlines how the WIPP will protect and preserve groundwater within and surrounding the WIPP facility. Groundwater protection is just one aspect of the WIPP environmental protection effort. The WIPP groundwater surveillance program is designed to determine statistically if any changes are occurring in groundwater characteristics within and surrounding the WIPP facility. If a change is noted, the cause will be determined and appropriate corrective action initiated.

  8. Using groundwater age to understand sources and dynamics of nutrient contamination through the catchment into Lake Rotorua, New Zealand

    Science.gov (United States)

    Morgenstern, U.; Daughney, C. J.; Leonard, G.; Gordon, D.; Donath, F. M.; Reeves, R.

    2014-08-01

    The water quality of Lake Rotorua has declined continuously over the past 50 yr despite mitigation efforts over recent decades. Delayed response of the groundwater discharges to historic land-use intensification 50 yr ago was the reason suggested by early tritium measurements, which indicated large transit times through the groundwater system. We use the isotopic and chemistry signature of the groundwater for detailed understanding of the origin, fate, flow pathways, lag times, and future loads of contaminants. A unique set of high-quality tritium data over more than four decades, encompassing the time when the tritium spike from nuclear weapons testing moved through the groundwater system, allows us to determine detailed age distribution parameters of the water discharging into Lake Rotorua. The Rotorua volcanic groundwater system is complicated due to the highly complex geology that has evolved through volcanic activity. Vertical and steeply-inclined geological contacts preclude a simple flow model. The extent of the Lake Rotorua groundwater catchment is difficult to establish due to the deep water table in large areas, combined with inhomogeneous groundwater flow patterns. Hierarchical cluster analysis of the water chemistry parameters provided evidence of the recharge source of the large springs near the lake shore, with discharge from the Mamaku ignimbrite through lake sediment layers. Groundwater chemistry and age data show clearly the source of nutrients that cause lake eutrophication, nitrate from agricultural activities and phosphate from geologic sources. With a naturally high phosphate load reaching the lake continuously via all streams, the only effective way to limit algae blooms and improve lake water quality in such environments is by limiting the nitrate load. The groundwater in the Rotorua catchment, once it has passed through the soil zone, shows no further decrease in dissolved oxygen, indicating absence of electron donors in the aquifer that

  9. 21 October 2008 - LHC Inauguration - Deputy Minister for Environment, Physical Planning and Public Works T. Xanthopulos welcomed by CERN Director-General R. Aymar, visiting the ATLAS cavern and LHC tunnel and signing the electronic guest book with E. Tsesmelis.

    CERN Multimedia

    CERN Photo Service

    2008-01-01

    21 October 2008 - LHC Inauguration - Deputy Minister for Environment, Physical Planning and Public Works T. Xanthopulos welcomed by CERN Director-General R. Aymar, visiting the ATLAS cavern and LHC tunnel and signing the electronic guest book with E. Tsesmelis.

  10. Electronic structure of {alpha}-Al{sub 2}O{sub 3} slabs: A local environment study

    Energy Technology Data Exchange (ETDEWEB)

    Darriba, German N., E-mail: darriba@fisica.unlp.edu.ar [Departamento de Fisica and Instituto de Fisica La Plata (IFLP, CONICET La Plata), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 67, 1900 La Plata (Argentina); Faccio, Ricardo [Crystallography, Solid State and Materials Laboratory (Cryssmat-Lab), DETEMA, Facultad de Quimica, Universidad de la Republica, Gral. Flores 2124, P.O. Box 1157, Montevideo (Uruguay); Centro NanoMat, Polo Tecnologico de Pando, Facultad de Quimica, Universidad de la Republica, Cno. Aparicio Saravia s/n, 91000, Pando, Canelones (Uruguay); Renteria, Mario [Departamento de Fisica and Instituto de Fisica La Plata (IFLP, CONICET La Plata), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 67, 1900 La Plata (Argentina)

    2012-08-15

    In this work we performed an ab initio/Density Functional Theory (DFT) study of structural and electronic properties of the (0 0 1) {alpha}-Al{sub 2}O{sub 3} surface. For this study we used two methods with different basis set: the Full-Potential Augmented Plane Wave plus local orbital (FP-APW+lo) and a linear combination of numerical localized atomic orbital basis sets, employing the WIEN2k code and the SIESTA code, respectively. In order to calculate the structural and electronic properties of the reconstructed surface, we calculated the final equilibrium atomic position with the SIESTA code and then the electric-field gradient (EFG) at Al sites was calculated with the FP-APW+lo code using the optimized positions. Using this procedure we found equilibrium structures with comparative lower energy than those obtained using only the FP-APW+lo method. The EFG tensor and the local structure for Al were studied as a function of the depth from the surface for the relaxed structures. We found that distances down to 6 A from the surface are sufficient to converge the EFG and the Al-O distances to bulk values. The predicted bulk EFG at the Al site is in good agreement with available experimental values. These results can be used for local probes purposes, e.g., in the case of doping, with important sensitivity for probes located close to the top of the surface, in particular for distances smaller than 6 A.

  11. 40 CFR Appendix Ix to Part 264 - Ground-Water Monitoring List

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-Water Monitoring List IX... Pt. 264, App. IX Appendix IX to Part 264—Ground-Water Monitoring List Ground-Water Monitoring List... species in the ground water that contain this element are included. 3 CAS index names are those used in...

  12. In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Xianjun, E-mail: xjxie@cug.edu.cn [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Wang, Yanxin, E-mail: yx.wang@cug.edu.cn [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Pi, Kunfu [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Liu, Chongxuan [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Pacific Northwest National Laboratory, Richland, WA 99354 (United States); Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China)

    2015-09-15

    In situ arsenic removal from groundwater by an aquifer iron coating method has great potential to be a cost effective and simple groundwater remediation technology, especially in rural and remote areas where groundwater is used as the main water source for drinking. The in situ arsenic removal technology was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions. The effectiveness was then evaluated in an actual high-arsenic groundwater environment. The arsenic removal mechanism by the coated iron oxide/hydroxide was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, electron probe microanalysis, and Fourier transformation infrared spectroscopy. Aquifer iron coating method was developed via a 4-step alternating injection of oxidant, iron salt and oxygen-free water. A continuous injection of 5.0 mmol/L FeSO{sub 4} and 2.5 mmol/L NaClO for 96 h can form a uniform goethite coating on the surface of quartz sand without causing clogging. At a flow rate of 7.2 mL/min of the injection reagents, arsenic (as Na{sub 2}HAsO{sub 4}) and tracer fluorescein sodium to pass through the iron-coated quartz sand column were approximately at 126 and 7 column pore volumes, respectively. The retardation factor of arsenic was 23.0, and the adsorption capacity was 0.11 mol As per mol Fe. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As(V) and Fe(II) reagents. Arsenic fixation resulted from a process of adsorption/co-precipitation with fine goethite particles by way of bidentate binuclear complexes. Therefore, the study results indicate that the high arsenic removal efficiency of the in situ aquifer iron coating technology likely resulted from the expanded specific surface area of the small goethite particles, which enhanced arsenic sorption capability and/or from co-precipitation of arsenic on the surface of goethite particles

  13. Quantifying shallow and deep groundwater inputs to rivers with groundwater dating in hydrological observatories.

    Science.gov (United States)

    Aquilina, Luc; Marçais, Jean; Gauvain, Alexandre; Kolbe, Tamara; de Dreuzy, Jean-Raynald; Labasque, Thierry; Abbott, Benjamin W.; Vergnaud, Virginie; Chatton, Eliot; Thomas, Zahra; Ruiz, Laurent; Bour, Olivier; Pinay, Gilles

    2017-04-01

    river from the groundwater age deduced from a deterministic model of the aquifer (Kolbe et al., 2016). The relationship between silica concentration determined with anthropogenic gases and observed silica concentration was strong (R2= 0.54-0.92), indicating that silica was a reliable geochemical chronometer, though it systematically underestimated anthropogenic gas age estimates. The difference could be accounted for by the very young water contribution : approximately 20 - 40% of overall discharge. Both approaches indicated that very young water is particularly important during winter and that deep groundwater contributes at least a third of the river discharge throughout the year. This last result has implications for river nitrate dynamics and understanding the potential limits of catchment management interventions which only reduce nitrate dynamics in shallow groundwater on decadal timescales. Aquilina L. et al., 2012 - Nitrate dynamics in agricultural catchments deduced from groundwater dating and long-term nitrate monitoring in surface- and groundwaters. Sci of the total Environment 435, 167-178. Kolbe et al., 2016 - Coupling 3D groundwater modeling with CFC-based age dating to classify local groundwater circulation in an unconfined crystalline aquifer. J. of Hydrology DOI: 10.1016/j.jhydrol.2016.05.020

  14. MAAC: a software tool for user authentication and access control to the electronic patient record in an open distributed environment

    Science.gov (United States)

    Motta, Gustavo H.; Furuie, Sergio S.

    2004-04-01

    Designing proper models for authorization and access control for the electronic patient record (EPR) is essential to wide scale use of the EPR in large health organizations. This work presents MAAC (Middleware for Authentication and Access Control), a tool that implements a contextual role-based access control (RBAC) authorization model. RBAC regulates user"s access to computers resources based on their organizational roles. A contextual authorization uses environmental information available at access-request time, like user/patient relationship, in order to decide whether a user has the right to access an EPR resource. The software architecture where MAAC is implemented uses Lightweight Directory Access Protocol, Java programming language and the CORBA/OMG standards CORBA Security Service and Resource Access Decision Facility. With those open and distributed standards, heterogeneous EPR components can request user authentication and access authorization services in a unified and consistent fashion across multiple platforms.

  15. The electronic nature of the 1,4-β-glycosidic bond and its chemical environment: DFT insights into cellulose chemistry.

    Science.gov (United States)

    Loerbroks, Claudia; Rinaldi, Roberto; Thiel, Walter

    2013-11-25

    The molecular understanding of the chemistry of 1,4-β-glucans is essential for designing new approaches to the conversion of cellulose into platform chemicals and biofuels. In this endeavor, much attention has been paid to the role of hydrogen bonding occurring in the cellulose structure. So far, however, there has been little discussion about the implications of the electronic nature of the 1,4-β-glycosidic bond and its chemical environment for the activation of 1,4-β-glucans toward acid-catalyzed hydrolysis. This report sheds light on these central issues and addresses their influence on the acid hydrolysis of cellobiose and, by analogy, cellulose. The electronic structure of cellobiose was explored by DFT at the BB1 K/6-31++G(d,p) level. Natural bond orbital (NBO) analysis was performed to grasp the key bonding concepts. Conformations, protonation sites, and hydrolysis mechanisms were examined. The results for cellobiose indicate that cellulose is protected against hydrolysis not only by its supramolecular structure, as currently accepted, but also by its electronic structure, in which the anomeric effect plays a key role.

  16. Feasibility of electronic peer mentoring for transition-age youth and young adults with intellectual and developmental disabilities: Project Teens making Environment and Activity Modifications.

    Science.gov (United States)

    Kramer, Jessica M; Ryan, Cathryn T; Moore, Rachel; Schwartz, Ariel

    2017-03-01

    There is a need for mentoring interventions in which transition-age youth and young adults with intellectual and/or developmental disabilities (I/DD) participate as both mentors and mentees. Project TEAM (Teens making Environment and Activity Modifications) is a problem-solving intervention that includes an electronic peer-mentoring component. Forty-two mentees and nine mentors with I/DD participated. The present authors analysed recorded peer-mentoring calls and field notes for mentee engagement, mentor achievement of objectives and supports needed to implement peer mentoring. Overall, mentees attended 87% of scheduled calls and actively engaged during 94% of call objectives. Across all mentoring dyads, mentors achieved 87% of objectives and there was a significant relationship between the use of supports (mentoring script, direct supervision) and fidelity. Transition-age mentees with I/DD can engage in electronic peer mentoring to further practice problem-solving skills. Mentors with I/DD can implement electronic peer mentoring when trained personnel provide supports and individualized job accommodations. © 2017 John Wiley & Sons Ltd.

  17. Manipulation of electronic structure via alteration of local orbital environment in [(SrIrO3)m,(SrTi O3)] (m =1 ,2 ,and ∞ ) superlattices

    Science.gov (United States)

    Kim, So Yeun; Kim, Choong H.; Sandilands, L. J.; Sohn, C. H.; Matsuno, J.; Takagi, H.; Kim, K. W.; Lee, Y. S.; Moon, S. J.; Noh, T. W.

    2016-12-01

    We investigated the electronic structure of [(SrIrO3)m,(SrTi O3)] (m =1 ,2 ,and ∞ ) superlattice (SL) thin films with optical spectroscopy and first principles calculations. Our optical results confirmed the existence of the Jeff= 1 /2 states in SL samples, similar to the bulk Ruddlesden-Popper series S rn+1I rnO3 n +1 iridates. Apart from this similarity, in the SL samples, we observed red shifts of the characteristic optical excitations in the Jeff= 1 /2 state and an enhancement of the low-energy spectral weight, which implies a reduction in the effective electron correlation for bands near the Fermi energy. The density functional theory plus Coulomb interactions (DFT +U ) calculations suggested that the SrTi O3 layer intervened between SrIr O3 layers in the SLs activated additional hopping channels between the Ir ions, thus increasing the bandwidth and reducing the effective strength of the correlations. This paper demonstrates that fabrication of iridium-based heterostructures can be used to finely tune electronic structures via alteration of their local orbital environments.

  18. Groundwater Quality Assessment Based on Geographical Information System and Groundwater Quality Index

    Directory of Open Access Journals (Sweden)

    Zahra Derakhshan

    2015-06-01

    Full Text Available Iran is located in an arid and semi-arid part of the world. Accordingly, the management of the water resources in the country is a priority. In this regard, determining the quality and pollution of surface water and groundwater is very important, especially in areas where groundwater resources are used for drinking. Groundwater quality index (GQI checks the components of the available water with various quality levels. To assess the quality of drinking groundwater of Yazd-Ardakan plain according to GQI in geographical information system (GIS environment, the electrical conductivity, sodium, calcium, magnesium, chlorine, pH, sodium adsorption ratio, bicarbonate, sulfate, potassium, water hardness, and all substances dissolved in the waters of 80 wells were determined. The samples were obtained from Yazd Regional Water Organization from 2005 to 2014. Using this data, the map components were plotted by Kriging geostatistical method. Then, the map of GQI was prepared after normalizing each map component, switching to a rating map, and extracting the weight of each component from the rating map. Based on the GQI index map, the index point which was 87 in 2005 has increased to 81 in 2014. These maps show a decline in groundwater quality from west to the east region. This decline in groundwater quality is due to the existence of Neogene Organizations in the east and geomorphologic unit of the bare epandage pediment in the west. The map removal and single-parameter sensitivity analysis showed that GQI index in Yazd-Ardakan plain is more sensitive to the components of electrical conductivity (EC, total dissolved solids (TDS, and total hardness (TH. Therefore, these components should be monitored more carefully and repeatedly.

  19. Review of emerging organic pollutants in groundwater in Slovenia

    Directory of Open Access Journals (Sweden)

    Anja Koroša

    2012-12-01

    Full Text Available Emerging organic compounds EOC are substances which have been only recently determined as pollutants,and substances which have been newly developed or discovered in the environment. EOC in groundwater cancause adverse effects on the environment and human health. They enter into the natural environment as a resultof various anthropogenic activities. The article provides an overview of emerging organic pollutants that occur ingroundwater. These compounds are drug residues, substances originating from personal care products, pesticides,veterinary products, food additives, nanomaterials, industrial and other compounds found in wastewater. Thearticle describes the main sources and the presence of EOC in groundwater, pathways and potential impacts(risks. An overview of EOC detection research in the world is presented. Within the review of Slovenian studiesthe investigations dealing with the determination of wide spectrum of EOC presence in groundwater, with drugresidues in groundwater and waste water, or with the development of analytical methods for these substanceswere analyzed. From the entire analysis we inferred that we must be aware of the possible presence of EOC riskin groundwatereven in small concentrations. To reduce the yet extent unknown risks, it is necessary to determineEOC threshold values in groundwater and their impact. In the future it will be necessary to identify new pollutants,to develop new analytical methods to determine their sources and routes, and in particular, to establishmonitoring for these substances.

  20. Patterns in groundwater chemistry resulting from groundwater flow

    Science.gov (United States)

    Stuyfzand, Pieter J.

    Groundwater flow influences hydrochemical patterns because flow reduces mixing by diffusion, carries the chemical imprints of biological and anthropogenic changes in the recharge area, and leaches the aquifer system. Global patterns are mainly dictated by differences in the flux of meteoric water passing through the subsoil. Within individual hydrosomes (water bodies with a specific origin), the following prograde evolution lines (facies sequence) normally develop in the direction of groundwater flow: from strong to no fluctuations in water quality, from polluted to unpolluted, from acidic to basic, from oxic to anoxic-methanogenic, from no to significant base exchange, and from fresh to brackish. This is demonstrated for fresh coastal-dune groundwater in the Netherlands. In this hydrosome, the leaching of calcium carbonate as much as 15m and of adsorbed marine cations (Na+, K+, and Mg2+) as much as 2500m in the flow direction is shown to correspond with about 5000yr of flushing since the beach barrier with dunes developed. Recharge focus areas in the dunes are evidenced by groundwater displaying a lower prograde quality evolution than the surrounding dune groundwater. Artificially recharged Rhine River water in the dunes provides distinct hydrochemical patterns, which display groundwater flow, mixing, and groundwater ages. Résumé Les écoulements souterrains influencent les différents types hydrochimiques, parce que l'écoulement réduit le mélange par diffusion, porte les marques chimiques de changements biologiques et anthropiques dans la zone d'alimentation et lessive le système aquifère. Ces types dans leur ensemble sont surtout déterminés par des différences dans le flux d'eau météorique traversant le sous-sol. Dans les "hydrosomes" (masses d'eau d'origine déterminée), les lignes marquant une évolution prograde (séquence de faciès) se développent normalement dans la direction de l'écoulement souterrain : depuis des fluctuations fortes de la

  1. Case studies illustrating in-situ remediation methods for soil and groundwater contaminated with petrochemicals

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, Robert A.; Lance, P.E.; Downs, A.; Kier, Brian P. [EMCON Northwest Inc., Portland, OR (United States)

    1993-12-31

    Four case studies of successful in-situ remediation are summarized illustrating cost-effective methods to remediate soil and groundwater contaminated with volatile and non-volatile petrochemicals. Each site is in a different geologic environment with varying soil types and with and without groundwater impact. The methods described include vadose zone vapor extraction, high-vacuum vapor extraction combined with groundwater tab.le depression, air sparging with groundwater recovery and vapor extraction, and bio remediation of saturated zone soils using inorganic nutrient and oxygen addition

  2. Groundwater hydrology instructional system

    Science.gov (United States)

    Schmidt, Ronald G.

    Wright State University, Dayton, Ohio, is preparing for its third cycle of the Interactive Remote Instructional System (IRIS) in groundwater hydrology, beginning January 15, 1986. The first cycle finished with an impressive completion ratio for registered participants, and the second cycle has currently been underway since July. This comprehensive hydrogeology program was originally developed for the Soil Conservation Service (of the U.S. Department of Agriculture) to prepare their personnel for professional practice work. Since its evolution into IRIS, an 80% participant completion rate has been recorded for the first cycle, which is a significant departure from success rates traditionally recorded by correspondence courses. This excellent rate of success is the result of 2 years of refinement and demonstrates the progressive nature of the program. IRIS has met the needs of participants by developing a curriculum that reflects current trends in the groundwater industry and has provided a unique educational approach that ensures maximum interaction between the instructional staff and participants.

  3. Contain contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Mutch, R.D. Jr.; Caputi, J.R. [Eckenfelder, Inc., Mahwah, NJ (United States); Ash, R.E. IV [Eckenfelder Inc., Nashville, TN (United States)

    1997-05-01

    Despite recent progress in innovative treatment technologies, many problems with contaminated groundwater still require the use of barrier walls, typically in combination with extraction and treatment systems. New technologies for subsurface barrier walls, mostly based on geomembranes, advancements in self-hardening slurries and permeation grouts with materials such as colloidal silica gel and montan wax emulsions, are being developed at an unprecedented pace. The paper discusses deep soil mixing, jet grouting, slurry trenches, and permeation grouting.

  4. Encapsulation of Prodan in beta-cyclodextrin environments: A critical study via electronic spectroscopy and molecular mechanics

    Science.gov (United States)

    Banerjee, Anwesha; Sengupta, Bidisa; Chaudhuri, Sudip; Basu, Kaushik; Sengupta, Pradeep K.

    2006-08-01

    We present a detailed study on the binding of the naphthalene based fluorescence probe Prodan with two cyclic oligosachharides namely, natural beta-cyclodextrin (β-CD) and its synthetic derivative, succinyl-2-hydroxypropyl beta-cyclodextrin (SHPβ-CD) using electronic absorption and fluorescence spectroscopy along with theoretical techniques. The encapsulation of Prodan inside the β-CD cavities leads to pronounced changes in its emission characteristics, including dramatic blue shifts (27 nm in 10 mM SHPβ-CD and 19 nm in 10 mM β-CD) in the emission maximum accompanied by increase in the emission yield, fluorescence anisotropy and lifetime values. Detailed analyses of the fluorescence along with relevant absorption spectroscopic data indicate that Prodan readily enters the doughnut-shaped hydrophobic cavities of the β-CDs and forms 1:1 inclusion complexes, the binding affinity being significantly higher in case of SHPβ-CD. Furthermore, docking studies performed via molecular mechanics methods (MM+) indicate that the dimethylamino group of Prodan is most likely to be oriented towards the wider rim of the cyclodextrin cavity. Quantum mechanical calculations reveal that incorporation of Prodan into the β-CD cavities, results in the formation of a N-TICT (dimethylamino twisted intramolecular charge transfer) state.

  5. A Holistic Assessment of the Sustainability of Groundwater Resources in the North China Plain

    Science.gov (United States)

    Cao, G.; Zheng, C.; Liu, J.; Li, W.

    2010-12-01

    The North China Plain (NCP) is one of the most important agricultural and economic regions of China and also one of the most densely populated in the world (~ 900 people/km2). In recent years, groundwater provides ~ 70% of the total water supply to support grain production, rapid economic development and population growth. Analysis of historical groundwater level contour maps and more than 230 monitoring well time series across the NCP shows a general long-term trend of depletion in groundwater storage in both shallow unconfined and deep confined aquifer zones. Groundwater depletion in the NCP has adversely affected the environment and ecosystems, including drying-up of rivers, land subsidence, seawater intrusion, and groundwater quality deterioration. The volume of groundwater depleted from the aquifer has been estimated from groundwater level fluctuation data by directly integrating the groundwater level change and specific yield across the NCP. The estimated amount of annual groundwater storage change based on this method is ~4 billion m3. A numerical groundwater flow model has been developed for the entire Quaternary aquifer of the NCP and is reasonably well calibrated for both the predevelopment period (1960s) and post-development conditions over the past 40 years. The output of the groundwater model provides estimates of groundwater depletion rates over the post-development period, and the model-calculated storage variation is consistent with the amount determined from groundwater level fluctuation data independent of the model. Moreover, the mean annual total recharge calibrated through the groundwater model is ~120 mm, which is in reasonable agreement with previously reported values based on the water balance method. The groundwater storage depletion derived either from the groundwater level fluctuation data or from the numerical simulation model is highly correlated with spatially averaged precipitation. The model simulations indicate that a decrease in

  6. The role of local environment on the electronic properties of a novel blue-emitting donor-acceptor compound

    Science.gov (United States)

    Legaspi, Christian M.; Stubbs, Regan E.; Yaron, David J.; Peteanu, Linda A.; Kemboi, Abraham; Picker, Jesse; Fossum, Eric

    2016-09-01

    With the rising popularity of organic light-emitting diodes (OLEDs) in display applications, demand for more efficient blue emitters has increased. We have recently synthesized a novel blue-emitting, donor-acceptor system employing carbazole as the donor and a benzothiazole derivative as the acceptor, BTZ-CBZ. We find that the solution-phase emission of BTZ-CBZ is highly dependent on solvent polarity, both in lineshape and emission maximum, showing a Stokes shift of 50 nm in methylcyclohexane and 150 nm in acetonitrile. This is expected behavior for donor-acceptor compounds due to the presence of a charge-transfer excited state. However, the solid state properties are more important for OLED devices. Using time-dependent density functional theory calculations employing the linear-response (LR) and state-specific (SS) polarizable continuum model (PCM), we explore the effects of solvent reorganization on the emission properties of BTZ-CBZ. SS-PCM reproduces the solvatochromism behavior of BTZ-CBZ in solution, but LR-PCM shows effectively no shift with solvent polarity. We surmise that this is because solvent reorganization is necessary for the solvatochromic effect to occur. The effect of rigid matrices on the emission of BTZ-CBZ has direct implications on its viability as a blue emitter in solid-state OLEDs and which molecular environments will be ideal for devices.

  7. Modelling groundwater over-extraction in the southern Jordan Valley with scarce data

    Science.gov (United States)

    Alfaro, Paulina; Liesch, Tanja; Goldscheider, Nico

    2017-08-01

    To deal with the challenge of groundwater over-extraction in arid and semi-arid environments, it is necessary to establish management strategies based on the knowledge of hydrogeological conditions, which can be difficult in places where hydrogeological data are dispersed, scarce or present potential misinformation. Groundwater levels in the southern Jordan Valley (Jordan) have decreased drastically in the last three decades, caused by over-extraction of groundwater for irrigation purposes. This study presents a local, two-dimensional and transient numerical groundwater model, using MODFLOW, to characterise the groundwater system and the water balance in the southern Jordan Valley. Furthermore, scenarios are simulated regarding hydrological conditions and management options, like extension of arable land and closure of illegal wells, influencing the projection of groundwater extraction. A limited dataset, literature values, field surveys, and the `crop water-requirement method' are combined to determine boundary conditions, aquifer parameters, and sources and sinks. The model results show good agreement between predicted and observed values; groundwater-level contours agree with the conceptual model and expected flow direction, and, in terms of water balance, flow volumes are in accordance with literature values. Average annual water consumption for irrigation is estimated to be 29 million m3 and simulation results show that a reduction of groundwater pumping by 40% could recover groundwater heads, reducing the water taken from storage. This study presents an example of how to develop a local numerical groundwater model to support management strategies under the condition of data scarcity.

  8. GROUNDWATER PROTECTION MANAGEMENT PROGRAM DESCRIPTION.

    Energy Technology Data Exchange (ETDEWEB)

    PAQUETTE,D.E.; BENNETT,D.B.; DORSCH,W.R.; GOODE,G.A.; LEE,R.J.; KLAUS,K.; HOWE,R.F.; GEIGER,K.

    2002-05-31

    THE DEPARTMENT OF ENERGY ORDER 5400.1, GENERAL ENVIRONMENTAL PROTECTION PROGRAM, REQUIRES THE DEVELOPMENT AND IMPLEMENTATION OF A GROUNDWATER PROTECTION PROGRAM. THE BNL GROUNDWATER PROTECTION MANAGEMENT PROGRAM DESCRIPTION PROVIDES AN OVERVIEW OF HOW THE LABORATORY ENSURES THAT PLANS FOR GROUNDWATER PROTECTION, MONITORING, AND RESTORATION ARE FULLY DEFINED, INTEGRATED, AND MANAGED IN A COST EFFECTIVE MANNER THAT IS CONSISTENT WITH FEDERAL, STATE, AND LOCAL REGULATIONS.

  9. Groundwater types in Southeast Srem

    Directory of Open Access Journals (Sweden)

    Gregorić Enike

    2009-01-01

    Full Text Available The region of Southeast Srem is rich in ground waters, which is of great significance to agricultural production. The objective of this paper was to designate the zones of different groundwater types from the aspect of recharge, based on the analysis of groundwater regimes in the study area. A very complex groundwater regime in Southeast Srem, which depends on a great number of natural and some anthropogenic factors, makes it difficult to designate clearly the zones of the three main types of groundwater regime. Still, the boundaries of the zones of groundwater regime types were defined based on the results of correlation analysis of the basic factors affecting the groundwater regime. Zone I includes the climatic type of groundwater. Its fluctuation corresponds to the vertical factors of water balance (precipitation and evaporation and it is not affected by the river water level. This zone extends North and East of the line Putinci, Golubinci, Stara Pazova, Batajnica, Dobanovci, mainly in the area of the loess plateau. Within the zone, groundwater is at a relatively great depth. Only exceptionally, in the valleys, it appears almost on the surface. Zone II includes the climatic-hydrological groundwater type, which is the transition between the climatic type and the hydrological type. The fluctuation of groundwater regime is affected both by the effect of vertical balance factors, and by the effect of watercourses. Climatic-hydrological groundwater type covers the central and the lowest part of the study area and the South part of the middle terrace. Zone III is classified as the hydrological groundwater type and it covers the riparian areas along the Sava and the Danube. The aquifer is hydraulically connected with the river Sava.

  10. SPECIFIC SOLUTIONS GROUNDWATER FLOW EQUATION

    OpenAIRE

    Syahruddin, Muhammad Hamzah

    2014-01-01

    Geophysic publication Groundwater flow under surface, its usually slow moving, so that in laminer flow condition can find analisys using the Darcy???s law. The combination between Darcy law and continuity equation can find differential Laplace equation as general equation groundwater flow in sub surface. Based on Differential Laplace Equation is the equation that can be used to describe hydraulic head and velocity flow distribution in porous media as groundwater. In the modeling Laplace e...

  11. Teamwork and Electronic Health Record Implementation: A Case Study of Preserving Effective Communication and Mutual Trust in a Changing Environment.

    Science.gov (United States)

    Gross, Anne H; Leib, Ryan K; Tonachel, Anne; Tonachel, Richard; Bowers, Danielle M; Burnard, Rachel A; Rhinehart, Catherine A; Valentim, Rahila; Bunnell, Craig A

    2016-11-01

    This article describes how trust among team members and in the technology supporting them was eroded during implementation of an electronic health record (EHR) in an adult outpatient oncology practice at a comprehensive cancer center. Delays in care of a 38-year-old woman with high-risk breast cancer occurred because of ineffective team communication and are illustrated in a case study. The case explores how the patient's trust and mutual trust between team members were disrupted because of inaccurate assumptions about the functionality of the EHR's communication tool, resultant miscommunications between team members and the patient, and the eventual recognition that care was not being effectively coordinated, as it had been previously. Despite a well-established, team-based culture and significant preparation for the EHR implementation, the challenges that occurred point to underlying human and system failures from which other organizations going through a similar process may learn. Through an analysis and evaluation of events that transpired before and during the EHR rollout, suggested interventions for preventing this experience are offered, which include: a thorough crosswalk between old and new communication mechanisms before implementation; understanding and mitigation of gaps in the communication tool's functionality; more robust training for staff, clinicians, and patients; greater consideration given to the pace of change expected of individuals; and development of models of collaboration between EHR users and vendors in developing products that support high-quality, team-based care in the oncology setting. These interventions are transferable to any organizational or system change that threatens mutual trust and effective communication.

  12. Fresh groundwater resources in a large sand replenishment

    Science.gov (United States)

    Huizer, Sebastian; Oude Essink, Gualbert H. P.; Bierkens, Marc F. P.

    2016-08-01

    The anticipation of sea-level rise and increases in extreme weather conditions has led to the initiation of an innovative coastal management project called the Sand Engine. In this pilot project a large volume of sand (21.5 million m3) - also called sand replenishment or nourishment - was placed on the Dutch coast. The intention is that the sand is redistributed by wind, current, and tide, reinforcing local coastal defence structures and leading to a unique, dynamic environment. In this study we investigated the potential effect of the long-term morphological evolution of the large sand replenishment and climate change on fresh groundwater resources. The potential effects on the local groundwater system were quantified with a calibrated three-dimensional (3-D) groundwater model, in which both variable-density groundwater flow and salt transport were simulated. Model simulations showed that the long-term morphological evolution of the Sand Engine results in a substantial growth of fresh groundwater resources, in all adopted climate change scenarios. Thus, the application of a local sand replenishment could provide coastal areas the opportunity to combine coastal protection with an increase of the local fresh groundwater availability.

  13. Predicting geogenic arsenic contamination in shallow groundwater of south Louisiana, United States.

    Science.gov (United States)

    Yang, Ningfang; Winkel, Lenny H E; Johannesson, Karen H

    2014-05-20

    Groundwater contaminated with arsenic (As) threatens the health of more than 140 million people worldwide. Previous studies indicate that geology and sedimentary depositional environments are important factors controlling groundwater As contamination. The Mississippi River delta has broadly similar geology and sedimentary depositional environments to the large deltas in South and Southeast Asia, which are severely affected by geogenic As contamination and therefore may also be vulnerable to groundwater As contamination. In this study, logistic regression is used to develop a probability model based on surface hydrology, soil properties, geology, and sedimentary depositional environments. The model is calibrated using 3286 aggregated and binary-coded groundwater As concentration measurements from Bangladesh and verified using 78 As measurements from south Louisiana. The model's predictions are in good agreement with the known spatial distribution of groundwater As contamination of Bangladesh, and the predictions also indicate high risk of As contamination in shallow groundwater from Holocene sediments of south Louisiana. Furthermore, the model correctly predicted 79% of the existing shallow groundwater As measurements in the study region, indicating good performance of the model in predicting groundwater As contamination in shallow aquifers of south Louisiana.

  14. Rapid, cost-effective estimation of groundwater age based on hydrochemistry

    Science.gov (United States)

    Beyer, M.; Morgenstern, U.; Jackson, B. M.; Daughney, C.

    2013-12-01

    In order to manage and protect groundwater resources, the complex and diverse recharge, mixing and flow processes occurring in groundwater systems need to be better understood. Groundwater age information can give valuable information on groundwater flow, recharge sources, and aquifer volumes. However current groundwater dating techniques, for example tracers such as tritium or CFCs, or hydrological models, have limitations and method specific application ranges and uncertainties. Due to this, ambiguous age interpretation is a problem. New technique(s) are essential to overcome limitations and complement existing methods. The aim of this study is to advance the use of hydrochemistry for groundwater dating. To date, hydrochemistry has only been applied sparsely to support groundwater age determination, despite its wide availability from national groundwater monitoring programs. This is due to the lack of any established distinct relationships between hydrochemistry and groundwater age. Establishing these is complex, since hydrochemistry is influenced by complex interrelationships of aquifer specific processes. Therefore underlying processes, such as mineral weathering and redox reactions, and diverse reactions, such as quartz dissolution, are not directly interpretable from hydrochemistry data. Additionally reaction kinetics (of e.g. quartz dissolution) are often aquifer specific, and field data are sparse; furthermore data gained in laboratory environments are difficult to relate back to field situations as comparative studies have found lab and field measurements can differ by orders of magnitude. We wish to establish relationships between hydrochemistry and groundwater age, to allow hydrochemical data to better inform groundwater dating through two separate approaches. Firstly relationships between groundwater age (determined by state of the art dating techniques) and single hydrochemistry parameters, such as silica concentration, can be established in a given

  15. Artificial recharge of groundwater: hydrogeology and engineering

    Science.gov (United States)

    Bouwer, Herman

    2002-02-01

    Artificial recharge of groundwater is achieved by putting surface water in basins, furrows, ditches, or other facilities where it infiltrates into the soil and moves downward to recharge aquifers. Artificial recharge is increasingly used for short- or long-term underground storage, where it has several advantages over surface storage, and in water reuse. Artificial recharge requires permeable surface soils. Where these are not available, trenches or shafts in the unsaturated zone can be used, or water can be directly injected into aquifers through wells. To design a system for artificial recharge of groundwater, infiltration rates of the soil must be determined and the unsaturated zone between land surface and the aquifer must be checked for adequate permeability and absence of polluted areas. The aquifer should be sufficiently transmissive to avoid excessive buildup of groundwater mounds. Knowledge of these conditions requires field investigations and, if no fatal flaws are detected, test basins to predict system performance. Water-quality issues must be evaluated, especially with respect to formation of clogging layers on basin bottoms or other infiltration surfaces, and to geochemical reactions in the aquifer. Clogging layers are managed by desilting or other pretreatment of the water, and by remedial techniques in the infiltration system, such as drying, scraping, disking, ripping, or other tillage. Recharge wells should be pumped periodically to backwash clogging layers. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s10040-001-0182-4.

  16. Gas desorption and up-scaling errors in CBM groundwater impact simulations

    Science.gov (United States)

    Herckenrath, D.; Doherty, J.

    2013-12-01

    Coalbed Methane (CBM) is a major energy resource in Australia. Production of CBM requires the extraction of large amounts of groundwater to enable gas desorption from the coalbeds. As CBM raises concerns regarding its impact on adjacent aquifer systems, groundwater models are often required for groundwater impact assessment. Questions arise about the suitability of traditional groundwater flow simulators for CBM groundwater impact quantification as 1) the gas phase is not simulated and 2) up-scaled properties are used that might not reflect coalbed properties appropriately. First, this study aims to quantify the errors incurred by neglecting gas desorption by comparing a CBM reservoir simulator (Eclipse) with an equivalent groundwater flow model (MODFLOW-USG) for a single 1m coal seam. Simulations show the groundwater model significantly overestimates drawdowns during the CBM production stage, as the desorbed gas volume is not accounted for, which impacts storage and the relative permeability of water that are assumed to be constant in the groundwater model. To improve the match between the groundwater model and CBM reservoir simulations, MODFLOW-USG was configured to implement a relationship that was obtained using a pseudo steady-state relationship between drawdown and desaturation derived from Eclipse simulations. A second set of simulations for a sequence of coalbeds was performed to quantify the impact of up-scaling on predicting drawdowns and to validate whether relative permeability curves in the CBM reservoir simulator still have integrity in an up-scaled context. These simulations will help understand how physically representative different up-scaled models are, what errors could be made when regional groundwater modelling is undertaken in a CBM environment and ultimately help decide whether a groundwater flow simulator can be used for CBM groundwater impact assessments. Key words: Coalbed Methane, Up-scaling, Reservoir model, Groundwater model, Dual

  17. The groundwater subsidy to vegetation: groundwater exchanges between landcover patches

    Science.gov (United States)

    Steven, L. I.; Gimenez, R.; Jobbagy, E. G.

    2015-12-01

    The Gran Chaco is a hot, dry plain, that spans over 60 million hectares across Bolivia, Paraguay, Brazil and Argentina. It supports high biodiversity in its dry forest and savannahs, but is rapidly being converted to agriculture in response to growing soy demand and technology including genetic modification and zero-till, that has made cultivation in drier landscapes more viable. Under natural conditions, the deep-rooted, native vegetation of the Chaco effectively captured all rainfall for evapotranspiration resulting in near zero groundwater recharge under the dry forest. Conversion to shallower rooted soy and corn, combined with the fallow period prior to the growing season, reduces evapotranspiration and allows some water to percolate through the root zone and recharge the groundwater system. When this groundwater recharge occurs, it creates groundwater mounding and a hydraulic gradient that drives flow to adjacent landcover patches where recharge does not occur. As the watertable rises, groundwater becomes available to the deep-rooted, dry forest vegetation. We develop a soil and groundwater flow model to simulate infiltration, percolation, evaporation, rootwater uptake, groundwater recharge and the lateral transfer of water between adjacent landcover patches to quantify this groundwater subsidy from converted agricultural lands to remnant patches of dry forest.

  18. Assessment of Hydrochemistry for Use as Groundwater Age Proxy

    Science.gov (United States)

    Beyer, Monique; Daughney, Chris; Jackson, Bethanna; Morgenstern, Uwe

    2015-04-01

    Groundwater dating can aid groundwater management by providing information on groundwater flow, mixing and residence-, storage- and exposure-time of groundwater in the subsurface. Groundwater age can be inferred from environmental tracers, such as tritium, SF6 and CFCs (CFC-12, -11 and -113). These tracers often need to be applied complementarily, since they have a restricted application range and ambiguous age interpretations can be obtained. Some tracers, such as the CFCs, will become of limited use in near future, due their fading out atmospheric concentration. As a consequence of these limitations, there is a need for additional, complementary tracers to ensure groundwater dating in future. Hydrochemistry parameters, such as the concentrations and ratios of major ions, appear to be promising candidates. Hydro-chemistry data at various spatial and temporal scales are widely available through local, regional and national groundwater monitoring programmes. Promising relationships between hydrochemistry parameters and groundwater residence time or aquifer depth have been found in near piston flow environments. However, most groundwater samples contain proportions of different aged water, due to mixing of water emerging from different flow lines during sampling or discharge, which complicates the establishment of hydrochemistry-time relationships in these environments. In this study, we establish a framework to infer hydrochemistry - (residence) time relationships in non-piston flow environments by using age information inferred from environmental tracer data and lumped parameter models (LPMs). The approach involves the generation of major element concentrations by 'classic' Monte Carlo simulation and subsequent comparison of simulated and observed element concentrations by means of an objective function to establish hydrochemistry-time relationships. The framework also allows for assessment of the hydrochemistry-time relationships with regards to their potential to

  19. Multiphase groundwater flow near cooling plutons

    Science.gov (United States)

    Hayba, D.O.; Ingebritsen, S.E.

    1997-01-01

    We investigate groundwater flow near cooling plutons with a computer program that can model multiphase flow, temperatures up to 1200??C, thermal pressurization, and temperature-dependent rock properties. A series of experiments examines the effects of host-rock permeability, size and depth of pluton emplacement, single versus multiple intrusions, the influence of a caprock, and the impact of topographically driven groundwater flow. We also reproduce and evaluate some of the pioneering numerical experiments on flow around plutons. Host-rock permeability is the principal factor influencing fluid circulation and heat transfer in hydrothermal systems. The hottest and most steam-rich systems develop where permeability is of the order of 10-15 m2. Temperatures and life spans of systems decrease with increasing permeability. Conduction-dominated systems, in which permeabilities are ???10-16m2, persist longer but exhibit relatively modest increases in near-surface temperatures relative to ambient conditions. Pluton size, emplacement depth, and initial thermal conditions have less influence on hydrothermal circulation patterns but affect the extent of boiling and duration of hydrothermal systems. Topographically driven groundwater flow can significantly alter hydrothermal circulation; however, a low-permeability caprock effectively decouples the topographically and density-driven systems and stabilizes the mixing interface between them thereby defining a likely ore-forming environment.

  20. Selection of Dispersivity in Groundwater Risk Assessment

    Institute of Scientific and Technical Information of China (English)

    武晓峰; 唐杰

    2004-01-01

    The Domenico model is used in combination with ASTM E 1739 in a Tier 2 risk assessment of chlorinated organic solvents contaminated groundwater sites to predict potential contaminant concentration in groundwater down-gradient from the point of exposure (POE). A knowledge of the dispersivity parameters is necessary for carrying out this calculation. A constant longitudinal dispersivity of 10 m is often used in analytical and numerical calculation. However, because of the scale effect of dispersion, two other main approaches are currently often used. From the viewpoint of conservative principle in risk assessment, it is necessary to determine which dispersivity data will give a higher predicted concentration, corresponding to a more conservative risk calculation. Generally, it is considered that a smaller dispersivity leads to a higher predicted concentration. This assumption is correct when dispersion is the only natural attenuation factor. However, degradation of commonly encountered chlorinated organic solvents in environment under natural condition has been widely reported. Calculations given in this paper of several representative cases show that a general consideration of the influence of dispersivity on concentration prediction is not always correct when a degradation term is included in the calculation. To give a conservative risk calculation, the scale effect of dispersion is considered. Calculations also show that the dispersivity parameters need to be determined by considering the POE distance from the source, the groundwater velocity, and the degradation rate of the contaminant.

  1. Radiogenic and Stable Isotope and Hydrogeochemical Investigation of Groundwater, Pajarito Plateau and Surrounding Areas, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Patrick Longmire, Michael Dale, Dale Counce, Andrew Manning, Toti Larson, Kim Granzow, Robert Gray, and Brent Newman

    2007-07-15

    From October 2004 through February 2006, Los Alamos National Laboratory, the New Mexico Environment Department-Department of Energy Oversight Bureau, and the United States Geological Survey conducted a hydrochemical investigation. The purpose of the investigation was to evaluate groundwater flow paths and determine groundwater ages using tritium/helium-3 and carbon-14 along with aqueous inorganic chemistry. Knowledge of groundwater age and flow paths provides a technical basis for selecting wells and springs for monitoring. Groundwater dating is also relevant to groundwater resource management, including aquifer sustainability, especially during periods of long-term drought. At Los Alamos, New Mexico, groundwater is either modern (post-1943), submodern (pre-1943), or mixed (containing both pre- and post-1943 components). The regional aquifer primarily consists of submodern groundwater. Mixed-age groundwater results from initial infiltration of surface water, followed by mixing with perched alluvial and intermediate-depth groundwater and the regional aquifer. No groundwater investigation is complete without using tritium/helium-3 and carbon-14 dating methods to quantify amounts of modern, mixed, and/or submodern components present in samples. Computer models of groundwater flow and transport at Los Alamos should be calibrated to groundwater ages for perched intermediate zones and the regional aquifer determined from this investigation. Results of this study clearly demonstrate the occurrence of multiple flow paths and groundwater ages occurring within the Sierra de los Valles, beneath the Pajarito Plateau, and at the White Rock Canyon springs. Localized groundwater recharge occurs within several canyons dissecting the Pajarito Plateau. Perched intermediate-depth groundwater and the regional aquifer beneath Pueblo Canyon, Los Alamos Canyon, Sandia Canyon, Mortandad Canyon, Pajarito Canyon, and Canon de Valle contain a modern component. This modern component consists

  2. The influence of leaf anatomy on the internal light environment and photosynthetic electron transport rate: exploration with a new leaf ray tracing model.

    Science.gov (United States)

    Xiao, Yi; Tholen, Danny; Zhu, Xin-Guang

    2016-11-01

    Leaf photosynthesis is determined by biochemical properties and anatomical features. Here we developed a three-dimensional leaf model that can be used to evaluate the internal light environment of a leaf and its implications for whole-leaf electron transport rates (J). This model includes (i) the basic components of a leaf, such as the epidermis, palisade and spongy tissues, as well as the physical dimensions and arrangements of cell walls, vacuoles and chloroplasts; and (ii) an efficient forward ray-tracing algorithm, predicting the internal light environment for light of wavelengths between 400 and 2500nm. We studied the influence of leaf anatomy and ambient light on internal light conditions and J The results show that (i) different chloroplasts can experience drastically different light conditions, even when they are located at the same distance from the leaf surface; (ii) bundle sheath extensions, which are strips of parenchyma, collenchyma or sclerenchyma cells connecting the vascular bundles with the epidermis, can influence photosynthetic light-use efficiency of leaves; and (iii) chloroplast positioning can also influence the light-use efficiency of leaves. Mechanisms underlying leaf internal light heterogeneity and implications of the heterogeneity for photoprotection and for the convexity of the light response curves are discussed.

  3. Biological Treatment of Groundwater Contaminated with Mixtures of Aromatic Compounds

    Science.gov (United States)

    1993-03-01

    aquitard. Localized high points in the Navarro clay topography, sometimes restrict lateral flow of the groundwater and dry zones associated with this...Portier, R.J., Hoover, D.G., Friday, D.O. and Sicard , J.L., "Biodegradation of Chlorinated Hydrocarbons in an Immobilized Bed Reactor," Environ. Progress 9

  4. Implications of groundwater quality to corrosion problem and urban ...

    African Journals Online (AJOL)

    Bheema

    interaction with subsurface water. Being the major ... dealt with hydrogeochemistry but none on the impact of water quality on water pipes and ...... contamination of surface and subsurface water and saline residues in soils. ... for water supply(lifting, transportation and distribution). ..... Groundwater in the Urban Environment.

  5. Biogeochemical dynamics of pollutants in Insitu groundwater remediation systems

    Science.gov (United States)

    Kumar, N.; Millot, R.; Rose, J.; Négrel, P.; Battaglia-Brunnet, F.; Diels, L.

    2010-12-01

    Insitu (bio) remediation of groundwater contaminants has been area of potential research interest in last few decades as the nature of contaminant encountered has also changed drastically. This gives tough challenge to researchers in finding a common solution for all contaminants together in one plume. Redox processes play significant role in pollutant dynamics and mobility in such systems. Arsenic particularly in reduced environments can get transformed into its reduced form (As3+), which is apparently more mobile and highly toxic. Also parallel sulfate reduction can lead to sulfide production and formation of thioarsenic species. On the other hand heavy metals (Zn, Fe, and Cd) in similar conditions will favour more stable metal sulfide precipitation. In the present work, we tested Zero Valent Iron (ZVI) in handling such issues and found promising results. Although it has been well known for contaminants like arsenic and chlorinated compounds but not much explored for heavy metals. Its high available surface area supports precipitation and co -precipitation of contaminants and its highly oxidizing nature and water born hydrogen production helps in stimulation of microbial activities in sediment and groundwater. These sulfate and Iron reducing bacteria can further fix heavy metals as stable metal sulfides by using hydrogen as potential electron donor. In the present study flow through columns (biotic and control) were set up in laboratory to understand the behaviour of contaminants in subsurface environments, also the impact of microbiology on performance of ZVI was studied. These glass columns (30 x 4cm) with intermediate sampling points were monitored over constant temperature (20°C) and continuous groundwater (up)flow at ~1ml/hr throughout the experiment. Simulated groundwater was prepared in laboratory containing sulfate, metals (Zn,Cd) and arsenic (AsV). While chemical and microbial parameters were followed regularly over time, solid phase has been

  6. Groundwater ages from the freshwater zone of the Edwards aquifer, Uvalde County, Texas—Insights into groundwater flow and recharge

    Science.gov (United States)

    Hunt, Andrew G.; Landis, Gary P.; Faith, Jason R.

    2016-02-23

    Tritium–helium-3 groundwater ages of the Edwards aquifer in south-central Texas were determined as part of a long-term study of groundwater flow and recharge in the Edwards and Trinity aquifers. These ages help to define groundwater residence times and to provide constraints for calibration of groundwater flow models. A suite of 17 samples from public and private supply wells within Uvalde County were collected for active and noble gases, and for tritium–helium-3 analyses from the confined and unconfined parts of the Edwards aquifer. Samples were collected from monitoring wells at discrete depths in open boreholes as well as from integrated pumped well-head samples. The data indicate a fairly uniform groundwater flow system within an otherwise structurally complex geologic environment comprised of regionally and locally faulted rock units, igneous intrusions, and karst features within carbonate rocks. Apparent ages show moderate, downward average, linear velocities in the Uvalde area with increasing age to the east along a regional groundwater flow path. Though the apparent age data show a fairly consistent distribution across the study area, many apparent ages indicate mixing of both modern (less than 60 years) and premodern (greater than 60 years) waters. This mixing is most evident along the “bad water” line, an arbitrary delineation of 1,000 milligrams per liter dissolved solids that separates the freshwater zone of the Edwards aquifer from the downdip saline water zone. Mixing of modern and premodern waters also is indicated within the unconfined zone of the aquifer by high excess helium concentrations in young waters. Excess helium anomalies in the unconfined aquifer are consistent with possible subsurface discharge of premodern groundwater from the underlying Trinity aquifer into the younger groundwater of the Edwards aquifer.

  7. Solutions Remediate Contaminated Groundwater

    Science.gov (United States)

    2010-01-01

    During the Apollo Program, NASA workers used chlorinated solvents to clean rocket engine components at launch sites. These solvents, known as dense non-aqueous phase liquids, had contaminated launch facilities to the point of near-irreparability. Dr. Jacqueline Quinn and Dr. Kathleen Brooks Loftin of Kennedy Space Center partnered with researchers from the University of Central Florida's chemistry and engineering programs to develop technology capable of remediating the area without great cost or further environmental damage. They called the new invention Emulsified Zero-Valent Iron (EZVI). The groundwater remediation compound is cleaning up polluted areas all around the world and is, to date, NASA's most licensed technology.

  8. Tracer attenuation in groundwater

    Science.gov (United States)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  9. Nature's Helpers: Using Microorganisms to Remove Trichloroethene (TCE) from Groundwater

    Science.gov (United States)

    Delgado, A. G.; Krajmlanik-Brown, R.; Fajardo-Williams, D.; Halloum, I.

    2015-12-01

    Organic chlorinated solvents, such as perchloroethene (PCE) and trichloroethene (TCE), are toxic pollutants threatening ground water quality worldwide and present at many superfund sites. Bioremediation using microorganisms is a promising, green, efficient, and sustainable approach to remove PCE and TCE contamination from soil and groundwater. Under anaerobic conditions, specialized microorganisms (dechlorinators) can reduce these chlorinated ethenes to ethene, an innocuous product, and gain energy for growth by a process known as reductive dechlorination. Dechlorinators are most often present in the environment and in dechlorinating cultures alongside other microbes such as fermenters, methanogens, and acetogens. Fermenters, methanogens, and acetogens syntrophically provide essential nutrients and growth factors to dechlorinators, most specifically to the only members able to reduce TCE all the way to ethene: Dehalococcoides; unfortunately, they also compete with dechlorinators for electron donors. My laboratory devises reductive chlorination platforms to study competition and syntrophy among Dehalococcoides, and other microbes to optimize remediation reactions and transport in the subsurface. We look at competing processes present as part of the natural soil chemistry and microbiology and address these challenges through a combination of enrichment techniques, molecular microbial ecology (deep sequencing), water chemistry, and electron balances. We have applied knowledge gathered in my laboratory to: 1) enrich microbial dechlorinating cultures capable of some of the fastest rates of TCE to ethene dechlorination ever reported, and 2) successfully design and operate three different continuous dechlorinating reactor types. We attribute our successful reactor operations to our multidisciplinary approach which links microbiology and engineering. Our reactors produce robust dechlorinating cultures used for in-situ bioaugmentation of PCE and TCE at contaminated sites

  10. Survey of chemical constituents of Tehran's groundwater.

    Science.gov (United States)

    Shariatpanahi, M; Anderson, A C

    1987-12-01

    One hundred and forty wells throughout the City of Tehran and its environs were sampled to determine the chemical quality of the groundwater. Total alkalinity, pH, conductivity, total dissolved solids, hardness and detergent concentrations were determined as well as levels of bicarbonate, calcium, magnesium, sulphate, chloride, sodium, potassium, fluoride, iodide and nitrate. Generally, chemical pollution of the water supplies was low. There were, however, regional elevations in nitrate, chloride and fluoride. Elevated fluoride levels were primarily in the northern regions of the city while high nitrates and chlorides were found primariiy in industrial areas. The health implications of chemical constituents in drinking water are discussed.

  11. Sustainable groundwater management in California

    Science.gov (United States)

    Phillips, Steven P.; Rogers, Laurel Lynn; Faunt, Claudia

    2015-12-01

    The U.S. Geological Survey (USGS) uses data collection, modeling tools, and scientific analysis to help water managers plan for, and assess, hydrologic issues that can cause “undesirable results” associated with groundwater use. This information helps managers understand trends and investigate and predict effects of different groundwater-management strategies.

  12. Promoting local management in groundwater

    Science.gov (United States)

    van Steenbergen, Frank

    2006-03-01

    There is a strong case for making greater effort to promote local groundwater management—in addition to other measures that regulate groundwater use. Though scattered, there are several examples—from India, Pakistan, Yemen and Egypt—where groundwater users effectively self-imposed restrictions on the use of groundwater. There are a number of recurrent themes in such spontaneously-developed examples of local regulation: the importance of not excluding potential users; the importance of simple, low transaction cost rules; the power of correct and accessible hydrogeological information; the possibility of making more use of demand and supply management strategies; and the important supportive role of local governments. The case is made, using examples, for actively promoting local groundwater management as an important element in balancing groundwater uses. Two programmes for promoting local groundwater management in South India are described—one focussing on participatory hydrological monitoring, and one focussing on micro-resource planning and training. In both cases the response was very positive and the conclusion is that promoting local groundwater regulation is not difficult, costly or sensitive and can reach the necessary scale quickly.

  13. Multimedia Environmental Pollutant Assessment System (MEPAS{reg_sign}): Groundwater pathway formulations

    Energy Technology Data Exchange (ETDEWEB)

    Whelan, G.; McDonald, J.P. [Pacific Northwest National Lab., Richland, WA (United States); Sato, C. [Idaho State Univ., Pocatello, ID (United States)

    1996-06-01

    This report describes the mathematical formulations used for contaminant fate and transport in the groundwater pathway of the Multimedia Environmental Pollutant Assessment System (MEPAS). It is one in a series of reports that collectively describe the components of MEPAS. The groundwater component of the MEPAS methodology models solute transport through the groundwater environment (i.e., partially saturated and saturated zones). Specifically, this component provides estimates of groundwater contaminant fluxes at various transporting medium interfaces (e.g., water table or aquifer/river interface) and contaminant concentrations at withdrawal wells. Contaminant fluxes at transporting medium interfaces represent boundary conditions for the next medium in which contaminant migration and fate is to be simulated (e.g., groundwater contamination entering a surface-water environment). Contaminant concentrations at withdrawal wells provide contaminant levels for the exposure assessment component of MEPAS. A schematic diagram illustrating the groundwater environment is presented. The migration and fate of contaminants through the groundwater environment are described by the three-dimensional, advective-dispersive equation for solute transport. The results are based on semianalytical solutions (i.e., solutions that require numerical integration) that are well established in the scientific literature. To increase computational efficiency, limits of integration are also identified.

  14. Decadal variations in groundwater quality

    DEFF Research Database (Denmark)

    Jessen, Søren; Postma, Dieke; Thorling, Lærke

    2017-01-01

    Twenty-five years of groundwater quality monitoring in a sandy aquifer beneath agricultural fields showed large temporal and spatial variations in major ion groundwater chemistry, which were linked closely to the nitrate (NO3) content of agricultural recharge. Between 1988 and 2013, the NO3 content...... loading. Agriculture thus is an important determinant of major ion groundwater chemistry. Temporal and spatial variations in the groundwater quality were simulated using a 2D reactive transport model, which combined effects of the historical NO3 leaching and denitrification, with dispersive mixing...... into the pristine groundwater residing deeper in the aquifer. Reactant-to-product ratios across reaction fronts are altered by dispersive mixing and transience in reactant input functions. Modelling therefore allowed a direct comparison of observed and simulated ratios of concentrations of NO3 (reactant...

  15. The Maryland Coastal Plain Aquifer Information System: A GIS-based tool for assessing groundwater resources

    Science.gov (United States)

    Andreasen, David C.; Nardi, Mark R.; Staley, Andrew W.; Achmad, Grufron; Grace, John W.

    2016-01-01

    Groundwater is the source of drinking water for ∼1.4 million people in the Coastal Plain Province of Maryland (USA). In addition, groundwater is essential for commercial, industrial, and agricultural uses. Approximately 0.757 × 109 L d–1 (200 million gallons/d) were withdrawn in 2010. As a result of decades of withdrawals from the coastal plain confined aquifers, groundwater levels have declined by as much as 70 m (230 ft) from estimated prepumping levels. Other issues posing challenges to long-term groundwater sustainability include degraded water quality from both man-made and natural sources, reduced stream base flow, land subsidence, and changing recharge patterns (drought) caused by climate change. In Maryland, groundwater supply is managed primarily by the Maryland Department of the Environment, which seeks to balance reasonable use of the resource with long-term sustainability. The chief goal of groundwater management in Maryland is to ensure safe and adequate supplies for all current and future users through the implementation of appropriate usage, planning, and conservation policies. To assist in that effort, the geographic information system (GIS)–based Maryland Coastal Plain Aquifer Information System was developed as a tool to help water managers access and visualize groundwater data for use in the evaluation of groundwater allocation and use permits. The system, contained within an ESRI ArcMap desktop environment, includes both interpreted and basic data for 16 aquifers and 14 confining units. Data map layers include aquifer and ­confining unit layer surfaces, aquifer extents, borehole information, hydraulic properties, time-series groundwater-level data, well records, and geophysical and lithologic logs. The aquifer and confining unit layer surfaces were generated specifically for the GIS system. The system also contains select groundwater-quality data and map layers that quantify groundwater and surface-water withdrawals. The aquifer

  16. Artificial recharge of groundwater

    Science.gov (United States)

    The Task Committee on Guidelines for Artificial Recharge of Groundwater, of the American Society of Civil Engineers' (ASCE) Irrigation and Drainage Division, sponsored an International Symposium on Artificial Recharge of Groundwater at the Inn-at-the-Park Hotel in Anaheim, Calif., August 23-27, 1988. Cosponsors were the U.S. Geological Survey, California Department of Water Resources, University of California Water Resources Center, Metropolitan Water District of Southern California, with cooperation from the U.S. Bureau of Reclamation, International Association of Hydrological Sciences, American Water Resources Association, U.S. Agency for International Development, World Bank, United Nations Department of Technical Cooperation for Development, and a number of local and state organizations.Because of the worldwide interest in artificial recharge and the need to develop efficient recharge facilities, the Anaheim symposium brought together an interdisciplinary group of engineers and scientists to provide a forum for many professional disciplines to exchange experiences and findings related to various types of artificial recharge; learn from both successful and unsuccessful case histories; promote technology transfer between the various disciplines; provide an education resource for communication with those who are not water scientists, such as planners, lawyers, regulators, and the public in general; and indicate directions by which cities or other entities can save funds by having reasonable technical guidelines for implementation of a recharge project.

  17. Annual Report of Groundwater Monitoring at Centralia, Kansas, in 2012

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, Lorraine M. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-06-01

    Periodic sampling is performed at Centralia, Kansas, on behalf of the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) by Argonne National Laboratory. The sampling is currently (2009-2012) conducted in accord with a monitoring program approved by the Kansas Department of Health and Environment (KDHE 2009). The objective is to monitor levels of carbon tetrachloride contamination identified in the groundwater sitewide (Argonne 2003, 2004, 2005a), as well as the response to the interim measure (IM) pilot test that is in progress (Argonne 2007b). This report provides a summary of the findings for groundwater inspection in Centralia.

  18. [Physical process based risk assessment of groundwater pollution in the mining area].

    Science.gov (United States)

    Sun, Fa-Sheng; Cheng, Pin; Zhang, Bo

    2014-04-01

    Case studies of groundwater pollution risk assessment at home and abroad generally start from groundwater vulnerability, without considering the influence of characteristic pollutants on the consequences of pollution too much. Vulnerability is the natural sensitivity of the environment to pollutants. Risk assessment of groundwater pollution should reflect the movement and distribution of pollutants in groundwater. In order to improve the risk assessment theory and method of groundwater pollution, a physical process based risk assessment methodology for groundwater pollution was proposed in a mining area. According to the sensitivity of the economic and social conditions and the possible distribution of pollutants in the future, the spatial distribution of risk levels in aquifer was ranged before hand, and the pollutant source intensity corresponding to each risk level was deduced accordingly. By taking it as the criterion for the classification of groundwater pollution risk assessment, the groundwater pollution risk in the mining area was evaluated by simulating the migration of pollutants in the vadose zone and aquifer. The result show that the risk assessment method of groundwater pollution based on physical process can give the concentration distribution of pollutants and the risk level in the spatial and temporal. For single punctuate polluted area, it gives detailed risk characterization, which is better than the risk assessment method that based on aquifer intrinsic vulnerability index, and it is applicable to the risk assessment of existing polluted sites, optimizing the future sites and providing design parameters for the site construction.

  19. Microbial community in high arsenic shallow groundwater aquifers in Hetao Basin of Inner Mongolia, China.

    Science.gov (United States)

    Li, Ping; Wang, Yanhong; Dai, Xinyue; Zhang, Rui; Jiang, Zhou; Jiang, Dawei; Wang, Shang; Jiang, Hongchen; Wang, Yanxin; Dong, Hailiang

    2015-01-01

    A survey was carried out on the microbial community of 20 groundwater samples (4 low and 16 high arsenic groundwater) and 19 sediments from three boreholes (two high arsenic and one low arsenic boreholes) in a high arsenic groundwater system located in Hetao Basin, Inner Mongolia, using the 454 pyrosequencing approach. A total of 233,704 sequence reads were obtained and classified into 12-267 operational taxonomic units (OTUs). Groundwater and sediment samples were divided into low and high arsenic groups based on measured geochemical parameters and microbial communities, by hierarchical clustering and principal coordinates analysis. Richness and diversity of the microbial communities in high arsenic sediments are higher than those in high arsenic groundwater. Microbial community structure was significantly different either between low and high arsenic samples or between groundwater and sediments. Acinetobacter, Pseudomonas, Psychrobacter and Alishewanella were the top four genera in high arsenic groundwater, while Thiobacillus, Pseudomonas, Hydrogenophaga, Enterobacteriaceae, Sulfuricurvum and Arthrobacter dominated high arsenic sediments. Archaeal sequences in high arsenic groundwater were mostly related to methanogens. Biota-environment matching and co-inertia analyses showed that arsenic, total organic carbon, SO4(2-), SO4(2-)/total sulfur ratio, and Fe(2+) were important environmental factors shaping the observed microbial communities. The results of this study expand our current understanding of microbial ecology in high arsenic groundwater aquifers and emphasize the potential importance of microbes in arsenic transformation in the Hetao Basin, Inner Mongolia.

  20. Microbial community in high arsenic shallow groundwater aquifers in Hetao Basin of Inner Mongolia, China.

    Directory of Open Access Journals (Sweden)

    Ping Li

    Full Text Available A survey was carried out on the microbial community of 20 groundwater samples (4 low and 16 high arsenic groundwater and 19 sediments from three boreholes (two high arsenic and one low arsenic boreholes in a high arsenic groundwater system located in Hetao Basin, Inner Mongolia, using the 454 pyrosequencing approach. A total of 233,704 sequence reads were obtained and classified into 12-267 operational taxonomic units (OTUs. Groundwater and sediment samples were divided into low and high arsenic groups based on measured geochemical parameters and microbial communities, by hierarchical clustering and principal coordinates analysis. Richness and diversity of the microbial communities in high arsenic sediments are higher than those in high arsenic groundwater. Microbial community structure was significantly different either between low and high arsenic samples or between groundwater and sediments. Acinetobacter, Pseudomonas, Psychrobacter and Alishewanella were the top four genera in high arsenic groundwater, while Thiobacillus, Pseudomonas, Hydrogenophaga, Enterobacteriaceae, Sulfuricurvum and Arthrobacter dominated high arsenic sediments. Archaeal sequences in high arsenic groundwater were mostly related to methanogens. Biota-environment matching and co-inertia analyses showed that arsenic, total organic carbon, SO4(2-, SO4(2-/total sulfur ratio, and Fe(2+ were important environmental factors shaping the observed microbial communities. The results of this study expand our current understanding of microbial ecology in high arsenic groundwater aquifers and emphasize the potential importance of microbes in arsenic transformation in the Hetao Basin, Inner Mongolia.

  1. The occurrence of groundwater in the Lower Palaeozoic rocks of upland Central Wales

    Directory of Open Access Journals (Sweden)

    C. Neal

    1997-01-01

    Full Text Available A series of boreholes of up to 50 m depth, drilled into Lower Palaeozoic mudstone, shale and greywacke bedrock in the headwater catchment areas of the River Severn at Plynlimon in Central Wales, shows an extensive chemically- and hydrologically-active shallow groundwater fracture flow system. Groundwater chemistry varies in space and time with lowest water levels and highest alkalinities occurring during the drier summer months. The groundwaters are enriched in base cations, silica, sulphate and alkalinity relative to surface waters indicating significant silicate weathering sources and sulphide oxidation. These sources provide important contributions to both stream water quality and flow. At one site, the introduction of a borehole near to the main river opened bedrock fractures which increased the amount of groundwater entering the river. This had a profound effect on the river water quality by increasing the pH, alkalinity and calcium concentrations. As well as pointing to the possibility of the wider availability of groundwater resources in upland areas, the results highlight (a the potential value of groundwater as a acid neutralizing resource, (b the importance of weathering processes and flow routing within the groundwater environment for stream water chemistry, (c the potential for altering stream water quality by manipulation of groundwater routing and (d the need to include groundwater characteristics in hydrochemical management models of surface water acidification.

  2. Reconstruction of groundwater depletion using a global scale groundwater model

    Science.gov (United States)

    de Graaf, Inge; van Beek, Rens; Sutanudjaja, Edwin; Wada, Yoshi; Bierkens, Marc

    2015-04-01

    Groundwater forms an integral part of the global hydrological cycle and is the world's largest accessible source of fresh water to satisfy human water needs. It buffers variable recharge rates over time, thereby effectively sustaining river flows in times of drought as well as evaporation in areas with shallow water tables. Moreover, although lateral groundwater flows are often slow, they cross topographic and administrative boundaries at appreciable rates. Despite the importance of groundwater, most global scale hydrological models do not consider surface water-groundwater interactions or include a lateral groundwater flow component. The main reason of this omission is the lack of consistent global-scale hydrogeological information needed to arrive at a more realistic representation of the groundwater system, i.e. including information on aquifer depths and the presence of confining layers. The latter holds vital information on the accessibility and quality of the global groundwater resource. In this study we developed a high resolution (5 arc-minutes) global scale transient groundwater model comprising confined and unconfined aquifers. This model is based on MODFLOW (McDonald and Harbaugh, 1988) and coupled with the land-surface model PCR GLOBWB (van Beek et al., 2011) via recharge and surface water levels. Aquifers properties were based on newly derived estimates of aquifer depths (de Graaf et al., 2014b) and thickness of confining layers from an integration of lithological and topographical information. They were further parameterized using available global datasets on lithology (Hartmann and Moosdorf, 2011) and permeability (Gleeson et al., 2014). In a sensitivity analysis the model was run with various hydrogeological parameter settings, under natural recharge only. Scenarios of past groundwater abstractions and corresponding recharge (Wada et al., 2012, de Graaf et al. 2014a) were evaluated. The resulting estimates of groundwater depletion are lower than

  3. Factors controlling groundwater salinization and hydrogeochemical processes in coastal aquifers from southern Spain.

    Science.gov (United States)

    Argamasilla, M; Barberá, J A; Andreo, B

    2017-02-15

    In detrital coastal aquifers, seawater and surface water may interact with groundwater in multiple ways. Understanding the interference of water fluxes in this type of environment is essential to effectively manage the groundwater resources in water-stressed regions, such as the Mediterranean coastal fringe. In this research, the characterization of the main hydrogeochemical processes and the interaction between surface water and groundwater in the Marbella-Estepona coastal aquifers (southern Spain) have been carried out by means of the combined use of different hydrogeochemical indicators along with isotope data. The results show that the diversity of source lithologies (peridotite, carbonate and/or metapelitic) substantially conditions the groundwater geochemistry. The analysis of ionic deltas made it possible a preliminary screening of the geochemical reactions that occur in the Marbella-Estepona aquifers, while the Discriminant Analysis allowed for a consistent classification of sampled groundwater types. The dissolution of calcite and dolomite determines the chemical composition of the groundwater from the eastern sector that are more conditioned by the rainwater infiltration. The dissolution of magnesium-bearing minerals (predominantly forming peridotite rocks) is observed in groundwater samples from the western and central sectors, whose chemical composition showed a greater influence of surface water. The spatial analysis of rCl(-)/Br(-) in groundwater has permitted to corroborate that saline intrusion is negligible, hardly affecting to its original water quality. The irregularly distributed recharge by precipitation (seasonal effect) and the atmospheric circulation of cloud fronts (coastal/continental effect) explains why most of groundwater sampled is isotopically impoverished with respect to the rainfall signature. The isotope approach also suggests the hydraulic relationship between surface water and groundwater in the study site. A deeper knowledge of

  4. Microbial fouling and corrosion of carbon steel in deep anoxic alkaline groundwater.

    Science.gov (United States)

    Rajala, Pauliina; Bomberg, Malin; Vepsäläinen, Mikko; Carpén, Leena

    2017-02-01

    Understanding the corrosion of carbon steel materials of low and intermediate level radioactive waste under repository conditions is crucial to ensure the safe storage of radioactive contaminated materials. The waste will be in contact with the concrete of repository silos and storage containers, and eventually with groundwater. In this study, the corrosion of carbon steel under repository conditions as well as the microbial community forming biofilm on the carbon steel samples, consisting of bacteria, archaea, and fungi, was studied over a period of three years in a groundwater environment with and without inserted concrete. The number of biofilm forming bacteria and archaea was 1,000-fold lower, with corrosion rates 620-times lower in the presence of concrete compared to the natural groundwater environment. However, localized corrosion was detected in the concrete-groundwater environment indicating the presence of local microenvironments where the conditions for pitting corrosion were favorable.

  5. Groundwater quality assessment for the Bear Creek Hydrogeologic Regime at the Y-12 Plant: 1991 groundwater quality data and calculated rate of contaminant migration

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    The report contains groundwater and surface water quality data obtained during the 1991 calendar year at several hazardous and non- hazardous waste management facilities associated with the US Department of Energy (DOE) Y-12 Plant (Figure 1). These sites are southwest of the Y-12 Plant complex within the Bear Creek Hydrogeologic Regime (BCHR), which is one of three regimes defined for the purposes of groundwater and surface-water quality monitoring and remediation (Figure 2). The Environmental Management Department of the Y-12 Plant Health, Safety, Environment, and Accountability (HSEA) Division manages the monitoring activities in each regime as part of the Y-12 Plant Groundwater Protection Program (GWPP).

  6. Groundwater Pollution and Vulnerability Assessment.

    Science.gov (United States)

    Kurwadkar, Sudarshan

    2017-10-01

    Groundwater is a critical resource that serve as a source of drinking water to large human population and, provide long-term water for irrigation purposes. In recent years; however, this precious resource being increasingly threatened, due to natural and anthropogenic activities. A variety of contaminants of emerging concern such as pharmaceuticals and personal care products, perfluorinated compounds, endocrine disruptors, and biological agents detected in the groundwater sources of both developing and developed nations. In this review paper, various studies have been included that documented instances of groundwater pollution and vulnerability to emerging contaminants of concern, pesticides, heavy metals, and leaching potential of various organic and inorganic contaminants from poorly managed residual waste products (biosolids, landfills, latrines, and septic tanks etc.). Understanding vulnerability of groundwater to pollution is critical to maintain the integrity of groundwater. A section on managed artificial recharge studies is included to highlight the sustainable approaches to groundwater conservation, replenishment and sustainability. This review paper is the synthesis of studies published in last one year that either documented the pollution problems or evaluated the vulnerability of groundwater pollution.

  7. An examination of electronic file transfer between host and microcomputers for the AMPMODNET/AIMNET (Army Material Plan Modernization Network/Acquisition Information Management Network) classified network environment

    Energy Technology Data Exchange (ETDEWEB)

    Hake, K.A.

    1990-11-01

    This report presents the results of investigation and testing conducted by Oak Ridge National Laboratory (ORNL) for the Project Manager -- Acquisition Information Management (PM-AIM), and the United States Army Materiel Command Headquarters (HQ-AMC). It concerns the establishment of file transfer capabilities on the Army Materiel Plan Modernization (AMPMOD) classified computer system. The discussion provides a general context for micro-to-mainframe connectivity and focuses specifically upon two possible solutions for file transfer capabilities. The second section of this report contains a statement of the problem to be examined, a brief description of the institutional setting of the investigation, and a concise declaration of purpose. The third section lays a conceptual foundation for micro-to-mainframe connectivity and provides a more detailed description of the AMPMOD computing environment. It gives emphasis to the generalized International Business Machines, Inc. (IBM) standard of connectivity because of the predominance of this vendor in the AMPMOD computing environment. The fourth section discusses two test cases as possible solutions for file transfer. The first solution used is the IBM 3270 Control Program telecommunications and terminal emulation software. A version of this software was available on all the IBM Tempest Personal Computer 3s. The second solution used is Distributed Office Support System host electronic mail software with Personal Services/Personal Computer microcomputer e-mail software running with IBM 3270 Workstation Program for terminal emulation. Test conditions and results are presented for both test cases. The fifth section provides a summary of findings for the two possible solutions tested for AMPMOD file transfer. The report concludes with observations on current AMPMOD understanding of file transfer and includes recommendations for future consideration by the sponsor.

  8. Functionalized magnetic mesoporous silica nanoparticles for U removal from low and high pH groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Li, Dien, E-mail: dien.li@srs.gov [Savannah River National Laboratory, Aiken, SC 29808 (United States); Egodawatte, Shani [Department of Chemistry, University of Iowa, Iowa City, IA 52242 (United States); Kaplan, Daniel I. [Savannah River National Laboratory, Aiken, SC 29808 (United States); Larsen, Sarah C. [Department of Chemistry, University of Iowa, Iowa City, IA 52242 (United States); Serkiz, Steven M. [Savannah River National Laboratory, Aiken, SC 29808 (United States); Department of Physics and Astronomy, Clemson University, Clemson, SC 29634 (United States); Seaman, John C. [Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802 (United States)

    2016-11-05

    Highlights: • Magnetic mesoporous silica nanoparticles were functionalized with organic molecules. • The functionalized nanoparticles had high surface areas and consistent pore sizes. • The functionalized nanoparticles were easily separated due to their magnetism. • They exhibited high capacity for uranium removal from low- or high-pH groundwater. - Abstract: U(VI) species display limited adsorption onto sediment minerals and synthetic sorbents in pH <4 or pH >8 groundwater. In this work, magnetic mesoporous silica nanoparticles (MMSNs) with magnetite nanoparticle cores were functionalized with various organic molecules using post-synthetic methods. The functionalized MMSNs were characterized using N{sub 2} adsorption-desorption isotherms, thermogravimetric analysis (TGA), transmission electron microscopy (TEM), {sup 13}C cross polarization and magic angle spinning (CPMAS) nuclear magnetic resonance (NMR) spectroscopy, and powder X-ray diffraction (XRD), which indicated that mesoporous silica (MCM-41) particles of 100–200 nm formed around a core of magnetic iron oxide, and the functional groups were primarily grafted into the mesopores of ∼3.0 nm in size. The functionalized MMSNs were effective for U removal from pH 3.5 and 9.6 artificial groundwater (AGW). Functionalized MMSNs removed U from the pH 3.5 AGW by as much as 6 orders of magnitude more than unfunctionalized nanoparticles or silica and had adsorption capacities as high as 38 mg/g. They removed U from the pH 9.6 AGW as much as 4 orders of magnitude greater than silica and 2 orders of magnitude greater than the unfunctionalized nanoparticles with adsorption capacities as high as 133 mg/g. These results provide an applied solution for treating U contamination that occurs at extreme pH environments and a scientific foundation for solving critical industrial issues related to environmental stewardship and nuclear power production.

  9. Distributed models coupling soakaways, urban drainage and groundwater

    DEFF Research Database (Denmark)

    Roldin, Maria Kerstin

    , and how these can be modeled in an integrated environment with distributed urban drainage and groundwater flow models. The thesis: 1. Identifies appropriate models of soakaways for use in an integrated and distributed urban water and groundwater modeling system 2. Develops a modeling concept that is able...... of the literature and on modeling studies, a new modeling concept is proposed which fulfills the need for integrated models coupling distributed urban drainage with groundwater. The suggested solution consists of a base equation for soakaway infiltration and additional components for clogging, upscaling......Alternative methods for stormwater management in urban areas, also called Water Sensitive Urban Design (WSUD) methods, have become increasingly important for the mitigation of urban stormwater management problems such as high runoff volumes, combined sewage overflows, poor water quality...

  10. Development of Groundwater Modeling Capacity in Mongolia: Keys to Success

    Science.gov (United States)

    Anderson, M. T.; Valder, J. F.; Carter, J. M.

    2015-12-01

    Ulaanbaatar, the capital city of Mongolia, is totally dependent on groundwater for its municipal and industrial water supply. Water is drawn from a network of shallow wells in an alluvial aquifer along the Tuul River. Evidence, however, suggests that current water use and especially the projected water demand from a rapidly growing urban population, is not sustainable from existing water sources. In response, the Mongolia Ministry of Environment and the Mongolian Fresh Water Institute requested technical assistance on groundwater modeling through the U.S. Army Corps of Engineers to the U.S. Geological Survey (USGS). Scientists from the USGS-SD Water Science Center provided a workshop to Mongolian water experts on basic principles of groundwater modeling using MODFLOW. The purpose of the workshop was to bring together representatives from the Government of Mongolia, local universities, technical experts, and other key stakeholders to build in-country capacity in hydrogeology and groundwater modeling. A preliminary steady-state groundwater flow model was developed to simulate groundwater conditions in the Tuul River Basin and for use in water use decision-making. The model consisted of 2 layers, 226 rows, and 260 columns with uniform 500 meter grid spacing. The upper model layer represented the alluvial aquifer and the lower layer represented the underlying bedrock, which includes areas characterized by permafrost. Estimated groundwater withdrawal was 180 m3/day, and estimated recharge was 114 mm/yr. The model will be modified and updated by Mongolian scientists as more data are available. Ultimately the model will be used to assist managers in developing a sustainable water supply, for current use and changing climate scenarios. A key to success was developing in-country technical capacity and partnerships with the Mongolian University of Science and Technology, Mongolian Freshwater Institute, a non-profit organization, UNESCO, and the government of Mongolia.

  11. Inner Radiation Belt Representation of the Energetic Electron Environment: Model and Data Synthesis Using the Salammbo Radiation Belt Transport Code and Los Alamos Geosynchronous and GPS Energetic Particle Data

    Science.gov (United States)

    Friedel, R. H. W.; Bourdarie, S.; Fennell, J.; Kanekal, S.; Cayton, T. E.

    2004-01-01

    The highly energetic electron environment in the inner magnetosphere (GEO inward) has received a lot of research attention in resent years, as the dynamics of relativistic electron acceleration and transport are not yet fully understood. These electrons can cause deep dielectric charging in any space hardware in the MEO to GEO region. We use a new and novel approach to obtain a global representation of the inner magnetospheric energetic electron environment, which can reproduce the absolute environment (flux) for any spacecraft orbit in that region to within a factor of 2 for the energy range of 100 KeV to 5 MeV electrons, for any levels of magnetospheric activity. We combine the extensive set of inner magnetospheric energetic electron observations available at Los Alamos with the physics based Salammbo transport code, using the data assimilation technique of "nudging". This in effect input in-situ data into the code and allows the diffusion mechanisms in the code to interpolate the data into regions and times of no data availability. We present here details of the methods used, both in the data assimilation process and in the necessary inter-calibration of the input data used. We will present sample runs of the model/data code and compare the results to test spacecraft data not used in the data assimilation process.

  12. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2012-01-01

    Groundwater is a vital resource and also a dynamic component of the water cycle. Unconfined aquifer storage is less responsive to short term weather conditions than the near surface terrestrial water storage (TWS) components (soil moisture, surface water, and snow). However, save for the permanently frozen regions, it typically exhibits a larger range of variability over multi-annual periods than the other components. Groundwater is poorly monitored at the global scale, but terrestrial water storage (TWS) change data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are a reasonable proxy for unconfined groundwater at climatic scales.

  13. Using groundwater age and hydrochemistry to understand sources and dynamics of nutrient contamination through the catchment into Lake Rotorua, New Zealand

    Science.gov (United States)

    Morgenstern, U.; Daughney, C. J.; Leonard, G.; Gordon, D.; Donath, F. M.; Reeves, R.

    2015-02-01

    The water quality of Lake Rotorua has steadily declined over the past 50 years despite mitigation efforts over recent decades. Delayed response of the groundwater discharges to historic land-use intensification 50 years ago was the reason suggested by early tritium measurements, which indicated large transit times through the groundwater system. We use the isotopic and chemistry signature of the groundwater for detailed understanding of the origin, fate, flow pathways, lag times and future loads of contaminants. A unique set of high-quality tritium data over more than four decades, encompassing the time when the tritium spike from nuclear weapons testing moved through the groundwater system, allows us to determine detailed age distribution parameters of the water discharging into Lake Rotorua. The Rotorua volcanic groundwater system is complicated due to the highly complex geology that has evolved through volcanic activity. Vertical and steeply inclined geological contacts preclude a simple flow model. The extent of the Lake Rotorua groundwater catchment is difficult to establish due to the deep water table in large areas, combined with inhomogeneous groundwater flow patterns. Hierarchical cluster analysis of the water chemistry parameters provided evidence of the recharge source of the large springs near the lake shore, with discharge from the Mamaku ignimbrite through lake sediment layers. Groundwater chemistry and age data show clearly the source of nutrients that cause lake eutrophication, nitrate from agricultural activities and phosphate from geologic sources. With a naturally high phosphate load reaching the lake continuously via all streams, the only effective way to limit algae blooms and improve lake water quality in such environments is by limiting the nitrate load. The groundwater in the Rotorua catchment, once it has passed through the soil zone, shows no further decrease in dissolved oxygen, indicating an absence of bioavailable electron donors along

  14. Y-12 Groundwater Protection Program Groundwater and Surface Water Sampling and Analysis Plan For Calendar Year 2009

    Energy Technology Data Exchange (ETDEWEB)

    Elvado Environmental LLC

    2008-12-01

    This plan provides a description of the groundwater and surface water quality monitoring activities planned for calendar year (CY) 2009 at the U.S. Department of Energy (DOE) Y-12 National Security Complex (Y-12) that will be managed by the Y-12 Groundwater Protection Program (GWPP). Groundwater and surface water monitoring performed by the GWPP during CY 2009 will be in accordance with DOE Order 540.1 requirements and the following goals: (1) to protect the worker, the public, and the environment; (2) to maintain surveillance of existing and potential groundwater contamination sources; (3) to provide for the early detection of groundwater contamination and determine the quality of groundwater and surface water where contaminants are most likely to migrate beyond the Oak Ridge Reservation property line; (4) to identify and characterize long-term trends in groundwater quality at Y-12; and (5) to provide data to support decisions concerning the management and protection of groundwater resources. Groundwater and surface water monitoring during CY 2009 will be performed primarily in three hydrogeologic regimes at Y-12: the Bear Creek Hydrogeologic Regime (Bear Creek Regime), the Upper East Fork Poplar Creek Hydrogeologic Regime (East Fork Regime), and the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime). The Bear Creek and East Fork regimes are located in Bear Creek Valley, and the Chestnut Ridge Regime is located south of Y-12 (Figure A.1). Additional surface water monitoring will be performed north of Pine Ridge, along the boundary of the Oak Ridge Reservation. Modifications to the CY 2009 monitoring program may be necessary during implementation. Changes in programmatic requirements may alter the analytes specified for selected monitoring wells or may add or remove wells from the planned monitoring network. All modifications to the monitoring program will be approved by the Y-12 GWPP manager and documented as addenda to this sampling and analysis plan

  15. Development of the control system of the ALICE transition radiation detector and of a test environment for quality-assurance of its front-end electronics

    Energy Technology Data Exchange (ETDEWEB)

    Mercado Perez, Jorge

    2008-11-10

    Within this thesis, the detector control system (DCS) for the Transition Radiation Detector (TRD) of the ALICE experiment at the Large Hadron Collider has been developed. The TRD DCS is fully implemented as a detector oriented hierarchy of objects behaving as finite state machines. It controls and monitors over 65 thousand front-end electronics (FEE) units, a few hundred low voltage and one thousand high voltage channels, and other sub-systems such as cooling and gas. Commissioning of the TRD DCS took place during several runs with ALICE using cosmic events. Another part of this thesis describes the development of a test environment for large-scale production quality-assurance of over 4 thousand FEE read-out boards containing in total about 1.2 million read-out channels. The hardware and software components are described in detail. Additionally, a series of performance studies were carried out earlier including radiation tolerance tests of the TRAP chip which is the core component of the TRD FEE. (orig.)

  16. FROM PHYSICAL BENCHMARKS TO MENTAL BENCHMARKS: A Four Dimensions Dynamic Model to Assure the Quality of Instructional Activities in Electronic and Virtual Learning Environments

    Directory of Open Access Journals (Sweden)

    Hamdy AHMED ABDELAZIZ

    2013-04-01

    Full Text Available The objective of this paper was to develop a four dimensions dynamic model for designing instructional activities appropriate to electronic and virtual learning environments. The suggested model is guided by learning principles of cognitivism, constructivism, and connectivism learning theories in order to help online learners to build and acquire meaningful knowledge and experiences. The proposed model consists of four dynamic dimensions: Ø Cognitive presence activities; Ø Psychological presence activities; Ø Social presence activities; and Ø Mental presence activities. Cognitive presence activities refer to learner’s ability to emerge a cognitive vision regarding the content of learning. The cognitive vision will be the starting point to construct meaningful understanding. Psychological presence activities refer to the learner’s ability to construct self awareness and trustworthiness. It will work as psychological schema to decrease the load of learning at distance. Social presence activities refer to the learner’s ability to share knowledge with others in a way to construct a community of practice and assure global understanding of learning. Finally, mental presence activities refer to learner’s ability to construct mental models that represent knowledge creation. It will help learners to make learning outcomes and experiences transferable. Applying the proposed model will improve the process of developing e-based activities throughout a set of adaptive and dynamic frameworks and guidelines to meet online learner’s cognitive, psychological, social and mental presence.

  17. 电子商务环境下的消费者行为态度研究%Research of consumer behavior under the environment of electronic commerce

    Institute of Scientific and Technical Information of China (English)

    殷锋社

    2012-01-01

    In view of consumer involvement degree high computer products, through the design of the questionnaire to obtain statistical data to build consumer behavior model, the model to test the hypothesis that further information in the B2C under the electronic commerce environment, attitude and behavior theory and technical innovation diffusion theory is still valid, online consumer computer behavior intention and attitude have significant correlation. For the rest of the consumers' disposable income accounted for a large proportion of the goods and services, the model still has a high application value.%针对消费者涉入程度高的计算机产品,通过问卷设计获得统计数据建立消费者行为态度模型,通过对模型的假设检验进一步说明在B2C电子商务环境下,态度行为理论和技术创新扩散理论仍然有效,消费者网上购买计算机的行为意图和态度之间存在显著的相关性。对于其余占消费者可支配收入比例大的商品与服务,模型仍然具有较高的应用价值。

  18. Hydrochemistry of groundwater from Sarabanga Minor Basin, Tamilnadu, India

    Directory of Open Access Journals (Sweden)

    K.Srinivasamoorthy

    2012-09-01

    Full Text Available The study area Sarabanga, forms an important Minor river basin of river Cauvery, situated in Salem district. The study area being a hard rock terrain with minimal rainfall and large extraction of groundwater for domestic, irrigational and industrial purposes have threatened the groundwater environment both in the terms of quality and quantity. Hence an attempt has been made to identify the major geochemical process activated for controlling the ground water chemistry. Groundwater was generally alkaline with higher EC values. The dominance of anions and cations were of the order of Cl > HCO3 > SO4 > NO3 > PO4 and Na > Ca > Mg > K. The plot for Na/Cl to EC indicates Na released from silicate weathering and Cl from anthropogenic activities. The plot for Ca+Mg to SO4+HCO3, indicates ion exchange process. The plot of Na-Cl to Ca+Mg-HCO3-SO4 confirms that Ca, Mg and Na concentrations in groundwater are derived from aquifer materials. Thermodynamic plot indicates that groundwater is in equilibrium with kaolinite, muscovite and chloride minerals. In general, water chemistry is guided by complex weathering process, ion exchange along with influence of Cl ions from anthropogenic impact.

  19. GWVis: A tool for comparative ground-water data visualization

    Science.gov (United States)

    Best, Daniel M.; Lewis, Robert R.

    2010-11-01

    The Ground-Water Visualization application ( GWVis) presents ground-water data visually in order to educate the public on ground-water issues. It is also intended for presentations to government and other funding agencies. GWVis works with ground-water level elevation data collected or modeled over a given time span, together with a matching fixed underlying terrain. GWVis was developed using the Python programming language in conjunction with associated extension packages and application program interfaces such as OpenGLTM to improve performance and allow us fine control of attributes of the model such as lighting, material properties, transformations, and interpolation. There are currently several systems available for visualizing ground-water data. We classify these into two categories: research-oriented models and static presentation-based models. While both of them have their strengths, we find the former overly complex and non-intuitive and the latter not engaging and presenting problems showing multiple data dimensions. GWVis bridges the gap between static and research based visualizations by providing an intuitive, interactive design that allows participants to view the model from different perspectives, infer information about simulations, and view a comparison of two datasets. By incorporating scientific data in an environment that can be easily understood, GWVis allows that information to be presented to a large audience base.

  20. 鲁西北平原区地热资源开发对地下水环境的影响%Effect of Geothermal Resources Exploitation to Groundwater Environment in Northwestern Plain in Shandong Province

    Institute of Scientific and Technical Information of China (English)

    王浩; 赵季初

    2015-01-01

    Geothermal resources is a new type energy which collect heat,water and mineral resource as a whole.It has the characteristics of small pollution,easy exploration,small investment and environmental protection.In the plain areas in northwestern Shandong province,geothermal wells are concentrated in ur-ban areas.Water intaking sections of geothermal wells in the same area ares are basically the same,devel-opment and utilization mode is single.There are no perfect recharge countermeasures,and tail water treat-ment process is simple,and sometimes geothermal water are even directly discharged.It has caused re-gional soil and water pollution in geothermal resources mining areas and discharging areas.In this paper, on the basis of surveying present condition of development and utilization of geothermal resources in the area,groundwater pollution situation in shallow and deep parts which may be caused in the process of de-velopment and utilization have been analyzed,and some prevention countermeasures and suggestions have been put forward as well.%地热资源是集热、水、矿为一体的新型能源,具有污染小、易开发、投资小和环保的特点。在鲁西北平原区地热井多集中分布在城区内,且同一地区地热井的取水区段基本一致,开发利用方式单一,没有较为完善的回灌措施,且尾水处理工艺简陋甚至直接排放,造成了地热资源开采区及排放流经区域水土污染,该文在对区内地热资源开发利用现状调查的基础上,对开发利用过程中可能引起的浅层及深层地下水污染情况进行了分析,并提出了一些防治措施与建议。

  1. An approach to managing cumulative effects to groundwater resources in the Alberta oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Fennell, J.; Forrest, Francine [WorleyParsons Canada, Infrastructure and Environment (Canada); Klebek, Margaret [Alberta Environment, Clean Energy Policy Branch (Canada)

    2011-07-01

    In the Athabasca region of Northern Alberta, oil sands activity has raised many concerns over how mining and extracting processes might affect groundwater quality and quantity. The groundwater management framework was developed by Alberta Environment to address these concerns by identifying and managing the potential environmental effects of oil sands activity on groundwater in a science-based manner. This paper develops the framework using risk identification and performance monitoring. The decision-making approach was conducted using decision support tools such as modeling, monitoring and management. Results showed the complexity and variability of groundwater conditions in the Athabasca region and pointed out that knowledge in this area is still developing. This paper presented how the groundwater management framework was developed and pointed out that it will have to be updated as new information arrives.

  2. GROUNDWATER HYDROCHEMISTRY EVALUATION IN RURAL ...

    African Journals Online (AJOL)

    Osondu

    2012-10-09

    Oct 9, 2012 ... the quality of groundwater from domestic water supply boreholes across rural Botswana. Ionic ... quality limits the supply of potable fresh water. To utilize and protect valuable water ..... prescribed specification of World Health.

  3. Groundwater Vulnerability Regions of Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The regions onThis map represent areas with similar hydrogeologic characteristics thought to represent similar potentials for contamination of groundwater and/or...

  4. Optimal and Sustainable Groundwater Extraction

    Directory of Open Access Journals (Sweden)

    Christopher A. Wada

    2010-08-01

    Full Text Available With climate change exacerbating over-exploitation, groundwater scarcity looms as an increasingly critical issue worldwide. Minimizing the adverse effects of scarcity requires optimal as well as sustainable patterns of groundwater management. We review the many sustainable paths for groundwater extraction from a coastal aquifer and show how to find the particular sustainable path that is welfare maximizing. In some cases the optimal path converges to the maximum sustainable yield. For sufficiently convex extraction costs, the extraction path converges to an internal steady state above the level of maximum sustainable yield. We describe the challenges facing groundwater managers faced with multiple aquifers, the prospect of using recycled water, and the interdependence with watershed management. The integrated water management thus described results in less water scarcity and higher total welfare gains from groundwater use. The framework also can be applied to climate-change specifications about the frequency, duration, and intensity of precipitation by comparing before and after optimal management. For the case of South Oahu in Hawaii, the prospect of climate change increases the gains of integrated groundwater management.

  5. Review of risk from potential emerging contaminants in UK groundwater.

    Science.gov (United States)

    Stuart, Marianne; Lapworth, Dan; Crane, Emily; Hart, Alwyn

    2012-02-01

    This paper provides a review of the types of emerging organic groundwater contaminants (EGCs) which are beginning to be found in the UK. EGCs are compounds being found in groundwater that were previously not detectable or known to be significant and can come from agricultural, urban and rural point sources. EGCs include nanomaterials, pesticides, pharmaceuticals, industrial compounds, personal care products, fragrances, water treatment by-products, flame retardants and surfactants, as well as caffeine and nicotine. Many are relatively small polar molecules which may not be effectively removed by drinking water treatment. Data from the UK Environment Agency's groundwater screening programme for organic pollutants found within the 30 most frequently detected compounds a number of EGCs such as pesticide metabolites, caffeine and DEET. Specific determinands frequently detected include pesticides metabolites, pharmaceuticals including carbamazepine and triclosan, nicotine, food additives and alkyl phosphates. This paper discusses the routes by which these compounds enter groundwater, their toxicity and potential risks to drinking water and the environment. It identifies challenges that need to be met to minimise risk to drinking water and ecosystems. Copyright © 2012. Published by Elsevier B.V.

  6. Influence of upwelling saline groundwater on iron and manganese cycling in the Rio Grande floodplain aquifer

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, Matthew F. [Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131 (United States)], E-mail: matthew.f.kirk@gmail.com; Crossey, Laura J. [Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131 (United States); Takacs-Vesbach, Cristina [Department of Biology, University of New Mexico, Albuquerque, NM 87131 (United States); Newell, Dennis L. [Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131 (United States); Bowman, Robert S. [Department of Earth and Environmental Science, New Mexico Tech, Socorro, NM 87801 (United States)

    2009-03-15

    Salinity contributions from upwelling groundwater significantly degrade water quality in the Rio Grande, a major source of water for the southwestern USA. This study considers the influence of this upwelling water on the geochemistry and microbiology of the Rio Grande floodplain alluvial aquifer. The composition of surface water, groundwater, and floodplain sediment samples collected from three transects in the Socorro Basin was examined. Terminal-restriction fragment length polymorphism (T-RFLP) was also used to examine microbial biomass samples. The distribution of salinity in the floodplain groundwater largely reflects the configuration of local groundwater flow and mixing of two major water sources, deeply-sourced saline groundwater and river water. Microbial populations in the shallow aquifer consume O{sub 2} and NO{sub 3}{sup -} and serve to redistribute metal oxides from the saturated zone to locations of groundwater discharge at the surface and possibly near the water table. The upwelling saline groundwater affects floodplain microbial processes by transporting reduced metals and organic electron donors to the alluvial aquifer system. This enhances metal reduction in the saturated zone and ultimately metal oxidation at or near the surface. Geochemical modeling suggests that mixing of the saline groundwater with more dilute water in the floodplain creates conditions more favorable for metal oxidation to occur and thereby influences the distribution of metal oxides.

  7. Groundwater Temperature in the Limmat Valley Aquifer, Zurich

    Science.gov (United States)

    Jung, Martin; Rivera, Jaime; Blum, Philipp; Bayer, Peter

    2014-05-01

    In metropolitan areas, the thermal environment is strongly influenced by the effects of urbanization. Urban climate is often described by Urban Heat Islands (UHIs), which are also observed in the shallow subsurface. On the one hand, these temperature anomalies may put sustainable development of urban ground at a risk, but on the other hand, enhanced ground temperatures represent potential energy reservoirs. In this contribution, we focus on the role of hydrogeological conditions for the development subsurface UHIs. As a study case, the Limmat valley forming the city center of Zurich is chosen. The Limmat valley is filled with widely heterogeneous, high-conductive moraine deposits, which host groundwater reaching close to the urban surface. By rigorous temperature-depth metering of the Limmat valley aquifer since the summer of 2013, and by compiling previously measured data, the intensity of Zurich's subsurface UHI is examined. This is done with respect to its special hydrogeology, which is dominated by large-scale infiltrations from the rivers Limmat and Sihl. These generate seasonal temperature variations in the groundwater, with increasing amplitudes in the vicinity of the rivers. The seasonal groundwater temperature changes in the Limmat valley are assessed by complementing measurements from summer and winter. The measurements reveal that groundwater temperatures in Zurich are generally high. Across the Limmat valley, values of beyond 13°C are regionally observed, which is around 4 K higher than annual surface air temperature and around 3 K higher than groundwater temperature in the rural surrounding. Though, urbanization is interpreted as a secondary factor (1-1.5K), as the river infiltration naturally causes high groundwater temperatures in the Limmat valley. In the permeable gravel, the temperature-depth-profiles measured in city wells often show little fluctuation. This may be due to horizontal and vertical mixing of the groundwater, and reflects the

  8. Environmental Effects of Groundwater Development in Xuzhou City, China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Xuzhou City is located in the most northwestern portion of Jiangsu Province, P. R. China. Karst groundwater in the Ordovician and Cambrian Limestone aquifers is the main source of water supply. There are 527 wells in urban areas to exploit the karst groundwater, yielding up to 35 000 m3 per day. After 1978, urbanization and industrialization of Xuzhou City have continued at a greatly accelerated pace; the population increased from 670 700 (1978) to 1 645 500 (2002), its GDP from 0.71 × 109$ to 42.7×109$ and the urban area from 184 km2 to 1,038 km2 (built-up city area from 41.3 km2 to 81.9 km2). The volume of karst groundwater withdrawal increased yearly before the operation of a supply plant of surface water in 1992, from 3.85×107 m3 (1978) to 1.34×108 m3 (1991) and now maintained at 0.1×109 m3 (2002). Intensive overexploitation of karst groundwater has caused a continuous descending of the piezometric level and the area of the depression cone increases year after year. These changes have increased the vulnerability of the karst groundwater system and have induced environmental problems such as depletion of water resources, water quality deterioration, groundwater contamination and karst collapse. The largest buried depth of karst groundwater is up to 100 m in the dry season in some areas, while 66 exhausted wells have been abandoned. A change in the thickness of the unsaturated zone due to the drawdown of the piezometric level has caused a change of the chemical environment which has an impact on the physical state and major chemical compositions in groundwater. The contents of Ca2+, Mg2+, NO3-, SO42- and Cl- in karst groundwater has increased significantly, total hardness (CaCO3 content) rises annually in most pumping wells and exceeds the Standard of Drinking Water of P.R. China. Point source pollution and belt-like pollution along the rivers has caused water quality deterioration. The sudden loss of buoyant support due to rapid drawdown of the

  9. Limitations of fibre optic distributed temperature sensing for quantifying surface water groundwater interactions

    Directory of Open Access Journals (Sweden)

    H. Roshan

    2014-07-01

    Full Text Available Studies of surface water–groundwater interactions using fiber optic distributed temperature sensing (FO-DTS has increased in recent years. However, only a few studies to date have explored the limitations of FO-DTS in detecting groundwater discharge to streams. A FO_DTS system was therefore tested in a flume under controlled laboratory conditions for its ability to accurately measure the discharge of hot or cold groundwater into a simulated surface water flow. In the experiment the surface water (SW and groundwater (GW velocities, expressed as ratios (vgw/vsw, were varied from 0.21% to 61.7%; temperature difference between SW-GW were varied from 2 to 10 °C; the direction of temperature gradient were varied with both cold and-hot water injection; and two different bed materials were used to investigate their effects on FO_DTS's detection limit of groundwater discharge. The ability of the FO_DTS system to detect the discharge of groundwater of a different temperature in the laboratory environment was found to be mainly dependent upon the surface and groundwater flow velocities and their temperature difference. A correlation was proposed to estimate the groundwater discharge from temperature. The correlation is valid when the ratio of the apparent temperature response to the source temperature difference is above 0.02.

  10. Will Jakarta Be The Next Atlantis? Excessive Groundwater Use Resulting From A Failing Piped Water Network

    Directory of Open Access Journals (Sweden)

    Nicola Colbran

    2009-06-01

    Full Text Available This article examines the connection between a failing piped water network and excessive groundwater use in Jakarta. It discusses the political history of the city's piped water network, which was privatised in 1998, and how privatisation was intended to increase access to clean, safe water for its residents. The article asserts that this has not eventuated, and that tap water remains costly, unreliable and does not provide noticeable benefits when compared with groundwater. The result is that households, industry, businesses, luxury apartment complexes and hotels choose alternative water sources and distribution methods, in particular groundwater. This is having an unsustainable impact on groundwater levels and Jakarta 's natural environment, causing significant land subsidence, pollution and salinisation of aquifers, and increased levels of flooding. The effect is so severe that the World Bank has predicted much of Jakarta will be inundated by seawater in 2025, rendering one third of the city uninhabitable and displacing millions. The article concludes by discussing and assessing the steps the government has taken to address excessive and unlicensed groundwater use. These steps include new regulations on groundwater, a public awareness campaign on the importance of groundwater and a commitment to improve the raw water supplied to the piped water network. However, the article observes that the government is yet to develop long term policies for improvement of the network itself. The question therefore remains, has the government done enough, or will groundwater use continue unabated making Jakarta the next lost city of Atlantis?

  11. A novel approach for direct estimation of fresh groundwater discharge to an estuary

    Science.gov (United States)

    Ganju, Neil K.

    2011-01-01

    Coastal groundwater discharge is an important source of freshwater and nutrients to coastal and estuarine systems. Directly quantifying the spatially integrated discharge of fresh groundwater over a coastline is difficult due to spatial variability and limited observational methods. In this study, I applied a novel approach to estimate net freshwater discharge from a groundwater-fed tidal creek over a spring-neap cycle, with high temporal resolution. Acoustic velocity instruments measured tidal water fluxes while other sensors measured vertical and lateral salinity to estimate cross-sectionally averaged salinity. These measurements were used in a time-dependent version of Knudsen's salt balance calculation to estimate the fresh groundwater contribution to the tidal creek. The time-series of fresh groundwater discharge shows the dependence of fresh groundwater discharge on tidal pumping, and the large difference between monthly mean discharge and instantaneous discharge over shorter timescales. The approach developed here can be implemented over timescales from days to years, in any size estuary with dominant groundwater inputs and well-defined cross-sections. The approach also directly links delivery of groundwater from the watershed with fluxes to the coastal environment. Copyright. Published in 2011 by the American Geophysical Union.

  12. Identification of nitrate sources in groundwater using a stable isotope and 3DEEM in a landfill in Northeast China

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhifei [School of Environment, Beijing Normal University, Beijing 100875 (China); State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Yang, Yu; Lian, Xinying [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Jiang, Yonghai, E-mail: jyhai203@126.com [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Xi, Beidou [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Lanzhou Jiaotong University, Gansu 730070 (China); Peng, Xing [School of Environment, Beijing Normal University, Beijing 100875 (China); State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); and others

    2016-09-01

    The groundwater was sampled in a typical landfill area of the Northeast China. Coupled stable isotope and three dimensional excitation–emission matrix (3DEEM) were applied to dentify diffused NO{sub 3}{sup −} inputs in the groundwater in this area. The results indicated that combined with the feature of groundwater hydrochemistry and three-dimensional fluorescence technology can effectively identify the nitrate pollution sources. The nitrate was derived from manure and sewage by δ{sup 15}N and δ{sup 18}O–NO{sub 3}{sup −} values of groundwater in the different periods. The excitation–emission matrix fluorescence spectroscopy was further evidence of groundwater DOM mainly which comes from the landfill. The protein-like was very significant at the sampling points near the landfill (SPNL), but only fulvic acid-like appeared at downstream of the landfill groundwater sampling points (DLGSP) in the study area. Partial denitrification processes helped to attenuate nitrate concentration in anaerobic environment. - Highlights: • We used stable isotope and 3DEEM to evaluate of nitrate sources. • Groundwater hydrochemistry was used to assess groundwater recharge. • The degradation process of organic matters was assessed using 3DEEM in groundwater. • This approach is a effective tool for trace to the nitrate sources in groundwater.

  13. The Electronic Forensics Process under Cloud Environment%云环境下电子取证方式与流程

    Institute of Scientific and Technical Information of China (English)

    骆智森

    2015-01-01

    in recent years, with the continuous development of cloud computing technology, our life also because cloud computing function has been a lot of convenience, convenient our daily some important information preservation. But the network also ap⁃peared a lot of for cloud computing or cloud computing to steal the target of cyber crime, both at the technical level or in law, cloud computing is gaining achievements is still not big enough, it also gives the cloud computing network security left a loophole. Rising trend of cyber crime, for a criminal record has been unable to use traditional methods of electronic evidence for forensic evidence, which for the evidence is a difficult challenge. Therefore, this paper will be electronic evidence of cloud computing research and analysis. At first, this paper analyzes the difficulty of obtaining evidence under the environment of cloud computing, then pointed out that the cloud computing environment of the primary collection objects, in the end, this article presents a new kind of cloud fo⁃rensics forensic methods. The final result of this article will evidence to bring a lot of convenience, can also provide some reference for the cloud forensics forensic investigators.%近年来,随着云计算技术的不断发展,我们的生活也因为云计算功能得到了很多的便利,方便我们日常的一些重要信息保存。可是网络上也出现了大量的针对云计算或以云计算为窃取目标的网络犯罪,无论是在技术层面还是在法律方面,云计算取得的成就还是不够大,这也给云计算的网络安全留下了一个漏洞。网络犯罪的趋势不断上涨,对犯罪记录进行取证的人员已经无法用传统的电子取证方法为案件取证,这对取证人员来说,是一个困难的挑战。因此,该文将会对云计算的电子取证进行探究和分析。该文首先分析了云计算环境下取证的困难,之后便点明了云计算环境下的

  14. Evaluation of the risk of diffuse pollution of groundwater by nitrogen substances from agricultural land use as background for allocation of effective measures

    Directory of Open Access Journals (Sweden)

    Bujnovský Radoslav

    2016-03-01

    Full Text Available The risk of diffuse pollution of groundwater by nitrogen substances from agricultural land is perceived as a result of the interaction of groundwater vulnerability (determined by the characteristics of the environment overlying groundwater in relation to water transport or soil solution and loading of overlying environment by nitrogen. Index of groundwater vulnerability was assessed on the basis of four parameters, namely, the amount of effective rainfall in the period from October to March, the capacity of soil to accumulate water, the average depth of the groundwater table and the permeability of the rock environment. Assessment of the index of loading of overlying environment by nitrogen was based on two parameters, namely, nitrogen balance and crop cover on agricultural land in the winter half on districts level in 2012, which corresponds with current state of the load. The resulting risk of groundwater pollution by nitrogen was expressed by the formula counting with the transformed values of groundwater vulnerability index and the index of loading of overlying environment by nitrogen. From practical point of view, the above mentioned indexes, as well as the subsequent risk of diffuse groundwater pollution, were spatially expressed via three associated categories. Based on the evaluation of relevant parameters, 5.18% of agricultural land falls into the category of very high and high risk, 42.20% in the medium risk category and 52.62% in the category of low and very low risk of diffuse pollution of groundwater by nitrogen from agricultural land.

  15. Nitrogen and phosphorus budgets for the Yucatán littoral: An approach for groundwater management.

    Science.gov (United States)

    Arandacirerol, Nancy; Comín, Francisco; Herrera-Silveira, Jorge

    2011-01-01

    Human activities have altered the balance of ecosystems to the detriment of natural environments. Eutrophication is a serious risk in Yucatán, a state in the eastern peninsula of México where groundwater supplies the only freshwater to a karst shelf environment. While economic development in Yucatán is increasing, environmental awareness is lagging, and efficient waste treatment systems are lacking. To assess potential nitrogen and phosphorus inputs into the coastal zone of Yucatán, we analyzed government reports and the chemical composition of groundwater and aquaculture wastewater. Swine, poultry, and tourism are revealed as the main continental nutrient sources, while groundwater with high nitrate concentrations is the principal coastal nutrient source, a pattern similar to other river discharges around the world. This study demonstrates that environmental risk management practices must be implemented in the Yucatán region to protect groundwater quality.

  16. Temporal variations of groundwater salinity and temperature in a tidal flat in front of a tide pool

    Science.gov (United States)

    Nakashita, Shinya; Hibino, Tadashi; Komai, Katsuaki; Narong, Touch

    2016-07-01

    of groundwater salinity were caused by water discharge from the tide pool, and that the groundwater salinity was increased by groundwater discharge during a flood event. We expect the groundwater flow around masonry revetment has important roles of substance transportation and formation of tidal flat environment. The consideration of this phenomenon will be important for construction of artificial tidal flat and improvement of tidal flat environment.

  17. Evaluation of Potential for Monitored Natural Attenuation of Perchlorate in Groundwater

    Science.gov (United States)

    2010-09-01

    Perchlorate-Impacted Groundwater for Base Case 8-4 Cost Components for Extraction and Treatment of Perchlorate-Impacted Groundwater for Base Case 8-5...consumed, increasing the likelihood of perchlorate biodegradation in the natural environment (Coates and Jackson, 2009). Trace amounts of molybdenum are...chlorinated solvents (USEPA, 1998) have been in use for many years. These documents describe systematic steps for delineating contaminant plumes

  18. Development and Evaluation of an Ultrasonic Groundwater Seepage Meter

    Science.gov (United States)

    Paulsen, R. J.; Smith, C. F.; O'Rourke, D.; Wong, T.; Bokuniewicz, H.

    2001-05-01

    Submarine groundwater discharge can influence significantly the near-shore transport and flux of chemicals into the oceans. Quantification of the sources and rates of such discharge requires a groundwater seepage meter that provides continuous measurements at high resolution over an extended period of time. An ultrasonic flow meter has been adapted for such measurements in the submarine environment. Connected to a steel collection funnel, the meter houses two piezoelectric transducers mounted at opposite ends of a cylindrical flow tube. By monitoring the perturbations of fluid flow on the propagation of sound waves inside the flow tube, the ultrasonic meter can measure both forward and reverse fluid flows in real time. Laboratory and field calibrations show that the ultrasonic meter can resolve groundwater discharges on the order of 0.1 μ m/s, and it is sufficiently robust for deployment in the field for several days. Data from West Neck Bay, Shelter Island, New York elucidate the temporal and spatial heterogeneity of submarine groundwater discharge and its interplay with tidal loading. A negative correlation between the discharge and tidal elevation was generally observed. A methodology was also developed whereby data for the sound velocity as a function of temperature can be used to infer the salinity and source of the submarine discharge. Independent measurements of electrical conductance were performed to validate this methodology. This meter has also been deployed as part of an international groundwater seepage intercomparison experiment with Scientific Committee on Oceanic Research (SCOR) / Land-Ocean Interaction in the Coastal Zone (LOICZ) Working Group 112. Results are in good agreement with other methodologies developed to quantify submarine groundwater discharge.

  19. Outline of the integrated simulation system (GEOMASS system) to evaluate groundwater flow and application to groundwater simulation in the Tono area

    Energy Technology Data Exchange (ETDEWEB)

    Inaba, Kaoru; Saegusa, Hiromitsu [Japan Nuclear Cycle Development Inst., Toki, Gifu (Japan). Tono Geoscience Center

    2003-03-01

    The Tono Geoscience Center (TGC) has been developing the GEOMASS system since 1997 to evaluate the groundwater flow at depth in a rock mass. The system provides an integrated simulation system environment for both model development and groundwater flow simulations. The integrated simulation system allows users to use resources efficiently. The system also allows users to make rapid improvement of their models as data increases. Also, it is possible to perform more realistic groundwater flow simulations due to the capability of modeling the rock mass as a continuum with discrete hydro-structural features in the rock. TGC tested the operation and usefulness of the GEOMASS system by applying to groundwater flow simulations in the Tono area, Gifu Prefecture. TGC confirmed that the system is very useful for complex geological models and multiple modeling. (author)

  20. Remediation of TCE-contaminated groundwater using nanocatalyst and bacteria.

    Science.gov (United States)

    Kang, Ser Ku; Seo, Hyunhee; Sun, Eunyoung; Kim, Inseon; Roh, Yul

    2011-08-01

    The objective of this study was to develop and evaluate the remediation of trichloroethene (TCE)-contaminated groundwater using both a nanocatalyst (bio-Zn-magnetite) and bacterium (similar to Clostridium quinii) in anoxic environments. Of the 7 nanocatalysts tested, bio-Zn-magnetite showed the highest TCE dechlorination efficiency, with an average of ca. 90% within 8 days in a batch experiment. The column tests confirmed that the application of bio-Zn-magnetite in combination with the bacterium achieved high degradation efficiency (ca. 90%) of TCE within 5 days compared to the nanocatalyst only, which degraded only 30% of the TCE. These results suggest that the application of a nanocatalyst and the bacterium have potential for the remediation of TCE-contaminated groundwater in subsurface environments.

  1. Groundwater recharge and agricultural contamination

    Science.gov (United States)

    Böhlke, J.K.

    2002-01-01

    Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water-rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agrilcultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3-, N2, Cl, SO42-, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3-, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.

  2. Geospatial Data Management Platform for Urban Groundwater

    Science.gov (United States)

    Gaitanaru, D.; Priceputu, A.; Gogu, C. R.

    2012-04-01

    Due to the large amount of civil work projects and research studies, large quantities of geo-data are produced for the urban environments. These data are usually redundant as well as they are spread in different institutions or private companies. Time consuming operations like data processing and information harmonisation represents the main reason to systematically avoid the re-use of data. The urban groundwater data shows the same complex situation. The underground structures (subway lines, deep foundations, underground parkings, and others), the urban facility networks (sewer systems, water supply networks, heating conduits, etc), the drainage systems, the surface water works and many others modify continuously. As consequence, their influence on groundwater changes systematically. However, these activities provide a large quantity of data, aquifers modelling and then behaviour prediction can be done using monitored quantitative and qualitative parameters. Due to the rapid evolution of technology in the past few years, transferring large amounts of information through internet has now become a feasible solution for sharing geoscience data. Furthermore, standard platform-independent means to do this have been developed (specific mark-up languages like: GML, GeoSciML, WaterML, GWML, CityML). They allow easily large geospatial databases updating and sharing through internet, even between different companies or between research centres that do not necessarily use the same database structures. For Bucharest City (Romania) an integrated platform for groundwater geospatial data management is developed under the framework of a national research project - "Sedimentary media modeling platform for groundwater management in urban areas" (SIMPA) financed by the National Authority for Scientific Research of Romania. The platform architecture is based on three components: a geospatial database, a desktop application (a complex set of hydrogeological and geological analysis

  3. Groundwater Annual Status Report for Fiscal Year 1998

    Energy Technology Data Exchange (ETDEWEB)

    A. K. Stoker; A. S. Johnson; B. D. Newman; B. M. Gallaher; C. L. Nylander; D. B. Rogers; D. E. Broxton; D. Katzman; E. H. Keating; G. L. Cole; K. A. Bitner; K. I. Mullen; P. Longmire; S. G. McLin; W. J. Stone

    1999-04-01

    Groundwater protection activities and hydrogeologic characterization studies are conducted at LANL annually. A summary of fiscal year 1998 results and findings shows increased understanding of the hydrogeologic environment beneath the Pajarito Plateau and significant refinement to elements of the LANL Hydrogeologic Conceptual Model pertaining to areas and sources of recharge to the regional aquifer. Modeling, drilling, monitoring, and data collection activities are proposed for fiscal year 1999.

  4. Managing Groundwater Radioactive Contamination at the Daiichi Nuclear Plant

    OpenAIRE

    Atsunao Marui; Adrian H. Gallardo

    2015-01-01

    The Great East Japan Earthquake and tsunami of March 2011 severely damagedthree reactors at the Fukushima Daiichi nuclear power station, leading to a major release of radiation into the environment. Groundwater flow through these crippled reactors continues to be one of the main causes of contamination and associated transport of radionuclides into the Pacific Ocean. In this context, a number of strategies are being implemented to manage radioactive pollution of the water resources at the nuc...

  5. Groundwater Annual Status Report for Fiscal Year 1999

    Energy Technology Data Exchange (ETDEWEB)

    C. L. Nylander; K. A. Bitner; K. Henning; A. S. Johnson; E. H. Keating; P. Longmire; B. D. Newman; B. Robinson; D. B. Rogers; W. J. Stone; D. Vaniman

    2000-03-01

    Groundwater protection activities and hydrogeologic characterization studies are conducted at Los Alamos National Laboratory annually. A summary of fiscal year 1999 results and findings shows increased understanding of the hydrogeologic environment beneath the Pajarito Plateau and significant refinement to elements of the LANL. Hydrogeologic Conceptual Model pertaining to areas and sources of recharge to the regional aquifer. Modeling, drilling, monitoring, and data collection activities are proposed for fiscal year 2000.

  6. Environmental and ground-water surveillance at Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Dirkes, R.L.; Luttrell, S.P.

    1995-06-01

    Environmental and ground-water surveillance of the Hanford Site and surrounding region is conducted to demonstrate compliance with environmental regulations, confirm adherence to DOE environmental protection policies, support DOE environmental management decisions, and provide information to the public. Environmental surveillance encompasses sampling and analyzing for potential radiological and nonradiological chemical contaminants on and off the Hanford Site. Emphasis is placed on surveillance of exposure pathways and chemical constituents that pose the greatest risk to human health and the environment.

  7. “互联网+”环境下的电子文件信息安全风险的界定%Definition of Information Security Risks of Electronic Records under"Internet+"Environment

    Institute of Scientific and Technical Information of China (English)

    史杰

    2016-01-01

    This article is started with the concept of the information security, information security risks, information se-curity of electronic records, electronic records of information security risks, discussed the information security of elec-tronic records and electronic records information security risks difference and relationship. Summarized the"Internet+"form of electronic records information security risks environment, put forward the concept of"protogenous risks","asso-ciated risks","congenital risks", and"posteriority risks". and pointed out in the"Internet+"environment, identifying information security risks elements of electronic records, under the"Internet+"environment of information security risks assessment and control, it possesses important practical significance.%文章从信息安全、信息安全风险、电子文件信息安全、电子文件信息安全风险的概念入手,讨论了电子文件信息安全与电子文件信息安全风险的区别与关系。归纳了“互联网+”环境下电子文件信息安全风险的表现形式,提出了“原生风险”、“伴生风险”、”先天风险“、”后天风险“的概念。指出在“互联网+”环境下,理清电子文件信息安全风险要素,对“互联网+”环境下电子文件信息安全风险进行评估与控制,具有重要的现实意义。

  8. Groundwater resource-directed measures software

    African Journals Online (AJOL)

    2006-07-21

    Jul 21, 2006 ... 1Institute for Groundwater Studies, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa ... In this paper the methods developed for the GRDM .... The geothermal gradient for groundwater, that is, the.

  9. ASSESSMENT OF GROUNDWATER QUALITY IN SHALLOW ...

    African Journals Online (AJOL)

    development of human societies. In Okrika Island ... abstraction of groundwater due to population increase in Port ... 298. Nwankwoala and Walter: Assessment of Groundwater Quality in Shallow Coastal Aquifers ..... and Tai-Eleme areas.

  10. Future research needs involving pathogens in groundwater

    Science.gov (United States)

    Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important barriers to preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to ...

  11. Valuing groundwater: A practical approach for integrating ...

    African Journals Online (AJOL)

    groundwater economic values into decision making ... The methodology incorporates a 2-tiered valuation approach. .... groundwater systems in Botswana (SADC, 2010). .... tion) can be investigated to support water resource management.

  12. INTEC Groundwater Monitoring Report 2006

    Energy Technology Data Exchange (ETDEWEB)

    J. R. Forbes

    2007-02-01

    This report summarizes 2006 perched water and groundwater monitoring activities at the Idaho Nuclear Technology and Engineering Center (INTEC) located at the Idaho National Laboratory (INL). During 2006, groundwater samples were collected from a total of 22 Snake River Plain Aquifer (SRPA) monitoring wells, plus six aquifer wells sampled for the Idaho CERCLA Disposal Facility (ICDF) monitoring program. In addition, perched water samples were collected from 21 perched wells and 19 suction lysimeters. Groundwater and perched water samples were analyzed for a suite of radionuclides and inorganic constituents. Laboratory results in this report are compared to drinking water maximum contaminant levels (MCLs). Such comparison is for reference only and it should be noted that the Operable Unit 3-13 Record of Decision does not require that perched water comply with drinking water standards.

  13. Groundwater arsenic contamination throughout China.

    Science.gov (United States)

    Rodríguez-Lado, Luis; Sun, Guifan; Berg, Michael; Zhang, Qiang; Xue, Hanbin; Zheng, Quanmei; Johnson, C Annette

    2013-08-23

    Arsenic-contaminated groundwater used for drinking in China is a health threat that was first recognized in the 1960s. However, because of the sheer size of the country, millions of groundwater wells remain to be tested in order to determine the magnitude of the problem. We developed a statistical risk model that classifies safe and unsafe areas with respect to geogenic arsenic contamination in China, using the threshold of 10 micrograms per liter, the World Health Organization guideline and current Chinese standard for drinking water. We estimate that 19.6 million people are at risk of being affected by the consumption of arsenic-contaminated groundwater. Although the results must be confirmed with additional field measurements, our risk model identifies numerous arsenic-affected areas and highlights the potential magnitude of this health threat in China.

  14. Electronic Photography

    Science.gov (United States)

    Payne, Meredith Lindsay

    1995-01-01

    The main objective was to assist in the production of electronic images in the Electronic Photography Lab (EPL). The EPL is a new facility serving the electronic photographic needs of the Langley community. The purpose of the Electronic Photography lab is to provide Langley with access to digital imaging technology. Although the EPL has been in operation for less than one year, almost 1,000 images have been produced. The decision to establish the lab was made after careful determination of the centers needs for electronic photography. The LaRC community requires electronic photography for the production of electronic printing, Web sites, desktop publications, and its increased enhancement capabilities. In addition to general use, other considerations went into the planning of the EPL. For example, electronic photography is much less of a burden on the environment compared to conventional photography. Also, the possibilities of an on-line database and retrieval system could make locating past work more efficient. Finally, information in an electronic image is quantified, making measurements and calculations easier for the researcher.

  15. A GIS-Enabled, Michigan-Specific, Hierarchical Groundwater Modeling and Visualization System

    Science.gov (United States)

    Liu, Q.; Li, S.; Mandle, R.; Simard, A.; Fisher, B.; Brown, E.; Ross, S.

    2005-12-01

    Efficient management of groundwater resources relies on a comprehensive database that represents the characteristics of the natural groundwater system as well as analysis and modeling tools to describe the impacts of decision alternatives. Many agencies in Michigan have spent several years compiling expensive and comprehensive surface water and groundwater inventories and other related spatial data that describe their respective areas of responsibility. However, most often this wealth of descriptive data has only been utilized for basic mapping purposes. The benefits from analyzing these data, using GIS analysis functions or externally developed analysis models or programs, has yet to be systematically realized. In this talk, we present a comprehensive software environment that allows Michigan groundwater resources managers and frontline professionals to make more effective use of the available data and improve their ability to manage and protect groundwater resources, address potential conflicts, design cleanup schemes, and prioritize investigation activities. In particular, we take advantage of the Interactive Ground Water (IGW) modeling system and convert it to a customized software environment specifically for analyzing, modeling, and visualizing the Michigan statewide groundwater database. The resulting Michigan IGW modeling system (IGW-M) is completely window-based, fully interactive, and seamlessly integrated with a GIS mapping engine. The system operates in real-time (on the fly) providing dynamic, hierarchical mapping, modeling, spatial analysis, and visualization. Specifically, IGW-M allows water resources and environmental professionals in Michigan to: * Access and utilize the extensive data from the statewide groundwater database, interactively manipulate GIS objects, and display and query the associated data and attributes; * Analyze and model the statewide groundwater database, interactively convert GIS objects into numerical model features

  16. Mercury speciation and transport via submarine groundwater discharge at a southern California coastal lagoon system

    Science.gov (United States)

    Ganguli, P.M.; Conaway, C.H.; Swarzenski, P.W.; Izbicki, J.A.; Flegal, A.R.

    2012-01-01

    We measured total mercury (Hg T) and monomethylmercury (MMHg) concentrations in coastal groundwater and seawater over a range of tidal conditions near Malibu Lagoon, California, and used 222Rn-derived estimates of submarine groundwater discharge (SGD) to assess the flux of mercury species to nearshore seawater. We infer a groundwater-seawater mixing scenario based on salinity and temperature trends and suggest that increased groundwater discharge to the ocean during low tide transported mercury offshore. Unfiltered Hg T (U-Hg T) concentrations in groundwater (2.2-5.9 pM) and seawater (3.3-5.2 pM) decreased during a falling tide, with groundwater U-Hg T concentrations typically lower than seawater concentrations. Despite the low Hg T in groundwater, bioaccumulative MMHg was produced in onshore sediment as evidenced by elevated MMHg concentrations in groundwater (0.2-1 pM) relative to seawater (???0.1 pM) throughout most of the tidal cycle. During low tide, groundwater appeared to transport MMHg to the coast, resulting in a 5-fold increase in seawater MMHg (from 0.1 to 0.5 pM). Similarly, filtered Hg T (F-Hg T) concentrations in seawater increased approximately 7-fold during low tide (from 0.5 to 3.6 pM). These elevated seawater F-Hg T concentrations exceeded those in filtered and unfiltered groundwater during low tide, but were similar to seawater U-Hg T concentrations, suggesting that enhanced SGD altered mercury partitioning and/or solubilization dynamics in coastal waters. Finally, we estimate that the SGD Hg T and MMHg fluxes to seawater were 0.41 and 0.15 nmol m -2 d -1, respectively - comparable in magnitude to atmospheric and benthic fluxes in similar environments. ?? 2012 American Chemical Society.

  17. Characteristics of high arsenic groundwater in Hetao Basin, Inner Mongolia, northern China

    Institute of Scientific and Technical Information of China (English)

    YangChun Zhu; XueYong Zhao; Min Chen; YongQing Luo; Xin Zhou

    2015-01-01

    It is well known that the Hetao Basin is one of the most seriously arsenic-affected groundwater areas in China. In order to understand the characteristics of high arsenic (As) groundwater in the Basin, a brief overview of arsenic in groundwater follows. High arsenic in the Basin commonly occurs in shallow groundwater and the total arsenic concentrations range from 0.58 to 572 µg/L (average 99.73 µg/L), exceeding the maximum mandated value of 10 µg/L for drinking water in China;As(Ш) is the predominant species. The regional distribution pattern of arsenic in the groundwater increases from south/southeast to north/northwest. Hangjinhouqi and Wuyuan counties are considered as the most seriously affected areas, with high incidences of endemic arsenicosic diseases in the Hetao Basin. High groundwater arsenic correlates with the increase of well depth. Previous studies proposed that groundwater arsenic in the Basin is mainly originated from desorption of some natural solid materials in the sediments, under reducing condition. Generally, reducing condition is believed to be the primary factor for arsenic releasing from the sediment to groundwater in the region. Under inorganic or bacterial processes, Fe2O3 changes to FeS and arsenic adsorbed to Fe(OH)3 dissolves into groundwater, and As(V) is re-duced to As(Ш). Besides, reducing environments, groundwater hydraulic gradients, organic matter, pH, evapotranspiration, and soil texture are presumed to be the predominant factors that control arsenic mobilization.

  18. Identification of Green Rust in Groundwater

    DEFF Research Database (Denmark)

    Christiansen, Bo C.; Balic Zunic, Tonci; Dideriksen, Knud

    2009-01-01

    Green rust, a family of Fe(II),Fe(III) layered double hydroxides, is believed to be present in environments close to the Fe(II)/Fe(III) transition zone. Attempts to identify members of this family in nature have proven difficult because the material is oxidized after only a few minutes exposure...... of synthetic GRCO3, the green rust familymemberwherecarbonate and water occupy the interlayer between the iron-hydroxide layers. The method was then tested on samples taken from an artesian well and a deep underground experimental station, both within the Fe(II)/Fe(III) redox zone. In both cases, GRCO3 could...... be identified. Currently, transport models for predicting the behavior of contaminants in groundwater do not include parameters for green rust. This work demonstrates they should....

  19. Food supply reliance on groundwater

    Science.gov (United States)

    Dalin, Carole; Puma, Michael; Wada, Yoshihide; Kastner, Thomas

    2016-04-01

    Water resources, essential to sustain human life, livelihoods and ecosystems, are under increasing pressure from population growth, socio-economic development and global climate change. As the largest freshwater resource on Earth, groundwater is key for human development and food security. Yet, excessive abstraction of groundwater for irrigation, driven by an increasing demand for food in recent decades, is leading to fast exhaustion of groundwater reserves in major agricultural areas of the world. Some of the highest depletion rates are observed in Pakistan, India, California Central Valley and the North China Plain aquifers. In addition, the growing economy and population of several countries, such as India and China, makes prospects of future available water and food worrisome. In this context, it is becoming particularly challenging to sustainably feed the world population, without exhausting our water resources. Besides, food production and consumption across the globe have become increasingly interconnected, with many areas' agricultural production destined to remote consumers. In this globalisation era, trade is crucial to the world's food system. As a transfer of water-intensive goods, across regions with varying levels of water productivity, food trade can save significant volumes of water resources globally. This situation makes it essential to address the issue of groundwater overuse for global food supply, accounting for international food trade. To do so, we quantify the current, global use of non-renewable groundwater for major crops, accounting for various water productivity and trade flows. This will highlight areas requiring quickest attention, exposing major exporters and importers of non-renewable groundwater, and thus help explore solutions to improve the sustainability of global food supply.

  20. Groundwater and climate change research scoping study

    OpenAIRE

    Jackson, C. R.; Cheetham, M.; Guha, P

    2006-01-01

    This scoping study has reviewed much of the published literature in the field of climate change and groundwater research. Whilst it is not exhaustive with regard to groundwater quality issues, most of the published literature relating to climate change and groundwater resources, particularly in the UK, is covered. Further work is required to identify current research needs relating to the effects of climate change on groundwater quality. The study of the effects of climate chan...

  1. Risk assessment of groundwater level variability using variable Kriging methods

    Science.gov (United States)

    Spanoudaki, Katerina; Kampanis, Nikolaos A.

    2015-04-01

    Assessment of the water table level spatial variability in aquifers provides useful information regarding optimal groundwater management. This information becomes more important in basins where the water table level has fallen significantly. The spatial variability of the water table level in this work is estimated based on hydraulic head measured during the wet period of the hydrological year 2007-2008, in a sparsely monitored basin in Crete, Greece, which is of high socioeconomic and agricultural interest. Three Kriging-based methodologies are elaborated in Matlab environment to estimate the spatial variability of the water table level in the basin. The first methodology is based on the Ordinary Kriging approach, the second involves auxiliary information from a Digital Elevation Model in terms of Residual Kriging and the third methodology calculates the probability of the groundwater level to fall below a predefined minimum value that could cause significant problems in groundwater resources availability, by means of Indicator Kriging. The Box-Cox methodology is applied to normalize both the data and the residuals for improved prediction results. In addition, various classical variogram models are applied to determine the spatial dependence of the measurements. The Matérn model proves to be the optimal, which in combination with Kriging methodologies provides the most accurate cross validation estimations. Groundwater level and probability maps are constructed to examine the spatial variability of the groundwater level in the basin and the associated risk that certain locations exhibit regarding a predefined minimum value that has been set for the sustainability of the basin's groundwater resources. Acknowledgement The work presented in this paper has been funded by the Greek State Scholarships Foundation (IKY), Fellowships of Excellence for Postdoctoral Studies (Siemens Program), 'A simulation-optimization model for assessing the best practices for the

  2. Groundwater flow and sorption processes in fractured rocks (I)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Young; Woo, Nam Chul; Yum, Byoung Woo; Choi, Young Sub; Chae, Byoung Kon; Kim, Jung Yul; Kim, Yoo Sung; Hyun, Hye Ja; Lee, Kil Yong; Lee, Seung Gu; Youn, Youn Yul; Choon, Sang Ki [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    This study is objected to characterize groundwater flow and sorption processes of the contaminants (ground-water solutes) along the fractured crystalline rocks in Korea. Considering that crystalline rock mass is an essential condition for using underground space cannot be overemphasized the significance of the characterizing fractured crystalline rocks. the behavior of the groundwater contaminants is studied in related to the subsurface structure, and eventually a quantitative technique will be developed to evaluate the impacts of the contaminants on the subsurface environments. The study has been carried at the Samkwang mine area in the Chung-Nam Province. The site has Pre-Cambrian crystalline gneiss as a bedrock and the groundwater flow system through the bedrock fractures seemed to be understandable with the study on the subsurface geologic structure through the mining tunnels. Borehole tests included core logging, televiewer logging, constant pressure fixed interval length tests and tracer tests. The results is summarized as follows; 1) To determine the hydraulic parameters of the fractured rock, the transient flow analysis produce better results than the steady - state flow analysis. 2) Based on the relationship between fracture distribution and transmissivities measured, the shallow part of the system could be considered as a porous and continuous medium due to the well developed fractures and weathering. However, the deeper part shows flow characteristics of the fracture dominant system, satisfying the assumptions of the Cubic law. 3) Transmissivities from the FIL test were averaged to be 6.12 x 10{sup -7}{sub m}{sup 2}{sub /s}. 4) Tracer tests result indicates groundwater flow in the study area is controlled by the connection, extension and geometry of fractures in the bedrock. 5) Hydraulic conductivity of the tracer-test interval was in maximum of 7.2 x 10{sup -6}{sub m/sec}, and the effective porosity of 1.8 %. 6) Composition of the groundwater varies

  3. Integrated groundwater management: An overview of concepts and challenges

    Science.gov (United States)

    Jakeman, Anthony J.; Barreteau, Olivier; Hunt, Randall J.; Rinaudo, Jean-Daniel; Ross, Andrew; Jakeman, Anthony J.; Barreteau, Olivier; Hunt, Randall J.; Rinaudo, Jean-Daniel; Ross, Andrew

    2016-01-01

    Managing water is a grand challenge problem and has become one of humanity’s foremost priorities. Surface water resources are typically societally managed and relatively well understood; groundwater resources, however, are often hidden and more difficult to conceptualize. Replenishment rates of groundwater cannot match past and current rates of depletion in many parts of the world. In addition, declining quality of the remaining groundwater commonly cannot support all agricultural, industrial and urban demands and ecosystem functioning, especially in the developed world. In the developing world, it can fail to even meet essential human needs. The issue is: how do we manage this crucial resource in an acceptable way, one that considers the sustainability of the resource for future generations and the socioeconomic and environmental impacts? In many cases this means restoring aquifers of concern to some sustainable equilibrium over a negotiated period of time, and seeking opportunities for better managing groundwater conjunctively with surface water and other resource uses. However, there are many, often-interrelated, dimensions to managing groundwater effectively. Effective groundwater management is underpinned by sound science (biophysical and social) that actively engages the wider community and relevant stakeholders in the decision making process. Generally, an integrated approach will mean “thinking beyond the aquifer”, a view which considers the wider context of surface water links, catchment management and cross-sectoral issues with economics, energy, climate, agriculture and the environment. The aim of the book is to document for the first time the dimensions and requirements of sound integrated groundwater management (IGM). The primary focus is on groundwater management within its system, but integrates linkages beyond the aquifer. The book provides an encompassing synthesis for researchers, practitioners and water resource managers on the concepts and

  4. Groundwater flow and sorption processes in fractured rocks (I)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Young; Woo, Nam Chul; Yum, Byoung Woo; Choi, Young Sub; Chae, Byoung Kon; Kim, Jung Yul; Kim, Yoo Sung; Hyun, Hye Ja; Lee, Kil Yong; Lee, Seung Gu; Youn, Youn Yul; Choon, Sang Ki [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    This study is objected to characterize groundwater flow and sorption processes of the contaminants (ground-water solutes) along the fractured crystalline rocks in Korea. Considering that crystalline rock mass is an essential condition for using underground space cannot be overemphasized the significance of the characterizing fractured crystalline rocks. the behavior of the groundwater contaminants is studied in related to the subsurface structure, and eventually a quantitative technique will be developed to evaluate the impacts of the contaminants on the subsurface environments. The study has been carried at the Samkwang mine area in the Chung-Nam Province. The site has Pre-Cambrian crystalline gneiss as a bedrock and the groundwater flow system through the bedrock fractures seemed to be understandable with the study on the subsurface geologic structure through the mining tunnels. Borehole tests included core logging, televiewer logging, constant pressure fixed interval length tests and tracer tests. The results is summarized as follows; 1) To determine the hydraulic parameters of the fractured rock, the transient flow analysis produce better results than the steady - state flow analysis. 2) Based on the relationship between fracture distribution and transmissivities measured, the shallow part of the system could be considered as a porous and continuous medium due to the well developed fractures and weathering. However, the deeper part shows flow characteristics of the fracture dominant system, satisfying the assumptions of the Cubic law. 3) Transmissivities from the FIL test were averaged to be 6.12 x 10{sup -7}{sub m}{sup 2}{sub /s}. 4) Tracer tests result indicates groundwater flow in the study area is controlled by the connection, extension and geometry of fractures in the bedrock. 5) Hydraulic conductivity of the tracer-test interval was in maximum of 7.2 x 10{sup -6}{sub m/sec}, and the effective porosity of 1.8 %. 6) Composition of the groundwater varies

  5. Complexed iron removal from groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Munter, R.; Ojaste, H.; Sutt, J. [Tallinn Technical University, Tallinn (Estonia). Dept. of Environmental & Chemical Technology

    2005-07-01

    The paper demonstrates an intensive work carried out and results obtained on the pilot plant of the City of Kogalym Water Treatment Station (Tjumen, Siberia, Russian Federation) to elaborate on a contemporary nonreagent treatment technology for the local iron-rich groundwater. Several filter materials (Birm, Pyrolox, hydroanthracite, Everzit, granulated activated carbon) and chemical oxidants (ozone, chlorine, hydrogen peroxide, oxygen, and potassium permanganate) were tested to solve the problem with complexed iron removal from groundwater. The final elaborated technology consists of raw water intensive aeration in the gas-degas treatment unit followed by sequential filtration through hydroanthracite and the special anthracite Everzit.

  6. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2014-01-01

    Terrestrial water storage (TWS) comprises groundwater, soil moisture, surface water, snow,and ice. Groundwater typically varies more slowly than the other TWS components because itis not in direct contact with the atmosphere, but often it has a larger range of variability onmultiannual timescales (Rodell and Famiglietti, 2001; Alley et al., 2002). In situ groundwaterdata are only archived and made available by a few countries. However, monthly TWSvariations observed by the Gravity Recovery and Climate Experiment (GRACE; Tapley et al.,2004) satellite mission, which launched in 2002, are a reasonable proxy for unconfinedgroundwater at climatic scales.

  7. Groundwater vulnerability mapping in Guadalajara aquifers system (Western Mexico)

    Science.gov (United States)

    Rizo-Decelis, L. David; Marín, Ana I.; Andreo, Bartolomé

    2016-04-01

    some monitoring wells, which have been related to anthropogenic activity. Vulnerability maps were produced using different parametric methods (e.g.: DRASTIC, GOD, DISCO, AVI), then the results are compared and assessed. Since each one of these methods use different number of parameters and weights, relatively different results were obtained, although the results have been evaluated with common cartographic inputs. The comparison between selected methods shows that the GOD method results are more correlated with the other methods and produces vulnerability maps comparable with them. Even though groundwater vulnerability is a critical issue around the world, no protection zones have been delineated in Guadalajara city, one of the biggest in Latin America. The groundwater contamination in the study area poses a serious risk for a large population and the environment. This work aims to propose an approach for groundwater protection cartography, based on the application and the comparison of results from different contamination vulnerability methods. These outcomes may assist water authorities to identify the higher vulnerable zones of the aquifers, in order to improving and adapting the land planning and management according to the protection of the own water resources.

  8. Mapping groundwater quality in the Netherlands

    NARCIS (Netherlands)

    Pebesma, Edzer Jan

    2001-01-01

    Groundwater quality is the suitability of groundwater for a certain purpose (e.g. for human consumption), and is mostly determined by its chemical composition. Pollution from agricultural and industrial origin threatens the groundwater quality in the Netherlands. Locally, this pollution is me

  9. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    Science.gov (United States)

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  10. Geochemical modelling baseline compositions of groundwater

    DEFF Research Database (Denmark)

    Postma, Diederik Jan; Kjøller, Claus; Andersen, Martin Søgaard

    2008-01-01

    Reactive transport models, were developed to explore the evolution in groundwater chemistry along the flow path in three aquifers; the Triassic East Midland aquifer (UK), the Miocene aquifer at Valreas (F) and the Cretaceous aquifer near Aveiro (P). All three aquifers contain very old groundwaters...... of the evolution in natural baseline properties in groundwater....

  11. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    Science.gov (United States)

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  12. Detection and Remediation of Groundwater Pollution

    Institute of Scientific and Technical Information of China (English)

    王杰

    2016-01-01

    Groundwater is an important part of the water cycle and is also widely used as sources of drinking water. With the increasing de?velopment of groundwater exploitation, the pollution is becoming more and more serious. This paper talks about the main research direc?tions of groundwater pollution, the detection, the remediation and some conclusions.

  13. Groundwater and geothermal: urban district heating applications

    Energy Technology Data Exchange (ETDEWEB)

    Mounts, R.; Frazier, A.; Wood, E.; Pyles, O.

    1982-01-01

    This report describes how several cities use groundwater and geothermal energy in district heating systems. It begins with groundwater, introducing the basic technology and techniques of development, and describing two case studies of cities with groundwater-based district heating systems. The second half of the report consists of three case studies of cities with district heating systems using higher temperature geothermal resources.

  14. State space modeling of groundwater fluctuations

    NARCIS (Netherlands)

    Berendrecht, W.L.

    2004-01-01

    Groundwater plays an important role in both urban and rural areas. It is therefore essential to monitor groundwater fluctuations. However, data that becomes available need to be analyzed further in order to extract specific information on the groundwater system. Until recently, simple linear time se

  15. Modification of spacecraft charging and the near-plasma environment caused by the interaction of an artificial electron beam with the earth's upper atmosphere

    DEFF Research Database (Denmark)

    Neubert, Torsten; Banks, P. M.; Gilchrist, B.E.

    1991-01-01

    The Beam-Atmosphere Interaction (BAI) involves the ionization created in the earth's upper atmosphere by electron beams emitted from a low altitude spacecraft. This process is described by two coupled non-linear differential electron transport equations for the up-going (along magnetic field line...

  16. U.S. Geological Survey groundwater toolbox, a graphical and mapping interface for analysis of hydrologic data (version 1.0): user guide for estimation of base flow, runoff, and groundwater recharge from streamflow data

    Science.gov (United States)

    Barlow, Paul M.; Cunningham, William L.; Zhai, Tong; Gray, Mark

    2015-01-01

    This report is a user guide for the streamflow-hydrograph analysis methods provided with version 1.0 of the U.S. Geological Survey (USGS) Groundwater Toolbox computer program. These include six hydrograph-separation methods to determine the groundwater-discharge (base-flow) and surface-runoff components of streamflow—the Base-Flow Index (BFI; Standard and Modified), HYSEP (Fixed Interval, Sliding Interval, and Local Minimum), and PART methods—and the RORA recession-curve displacement method and associated RECESS program to estimate groundwater recharge from streamflow data. The Groundwater Toolbox is a customized interface built on the nonproprietary, open source MapWindow geographic information system software. The program provides graphing, mapping, and analysis capabilities in a Microsoft Windows computing environment. In addition to the four hydrograph-analysis methods, the Groundwater Toolbox allows for the retrieval of hydrologic time-series data (streamflow, groundwater levels, and precipitation) from the USGS National Water Information System, downloading of a suite of preprocessed geographic information system coverages and meteorological data from the National Oceanic and Atmospheric Administration National Climatic Data Center, and analysis of data with several preprocessing and postprocessing utilities. With its data retrieval and analysis tools, the Groundwater Toolbox provides methods to estimate many of the components of the water budget for a hydrologic basin, including precipitation; streamflow; base flow; runoff; groundwater recharge; and total, groundwater, and near-surface evapotranspiration.

  17. Calendar year 1993 groundwater quality report for the Chestnut Ridge Hydrogeologic Regime, Y-12 Plant, Oak Ridge, Tennessee. 1993 groundwater quality data and calculated rate of contaminant migration, Part 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This annual groundwater report contains groundwater quality data obtained during the 1993 calendar year (CY) at several hazardous and non-hazardous waste-management facilities associated with the US Department of Energy (DOE) Y-12 Plant located on the DOE Oak Ridge Reservation (ORR) southeast of Oak Ridge, Tennessee. These sites are located south of the Y-12 Plant in the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime), which is one of three regimes defined for the purposes of groundwater quality monitoring at the Y-12 Plant. The Environmental Management Department of the Y-12 Plant Health, Safety, Environment, and Accountability Organization manages the groundwater monitoring activities in each regime as part of the Y-12 Plant Groundwater Protection Program (GWPP). The annual groundwater report for the Chestnut Ridge Regime is completed in two-parts; Part 1 (this report) containing the groundwater quality data and Part 2 containing a detailed evaluation of the data. The primary purpose of this report is to serve as a reference for the groundwater quality data obtained each year under the lead of the Y-12 Plant GWPP. However, because it contains information needed to comply with Resource Conservation and Recovery Act (RCRA) interim status assessment monitoring and reporting requirements, this report is submitted to the Tennessee Department of Health and Environment (TDEC) by the RCRA reporting deadline.

  18. ANALYTICAL SOLUTION OF GROUNDWATER FLUCTUATIONS IN ESTUARINE AQUIFER

    Institute of Scientific and Technical Information of China (English)

    CHEN Jing; ZHOU Zhi-fang; JIA Suo-bao

    2005-01-01

    As a basic factor in the environment of estuary, tidal effects in the coastal aquifer have recently attracted much attention because tidal dynamic also greatly influences the solute transport in the coastal aquifer. Previous studies on tidal dynamic of coastal aquifers have focused on the inland propagation of oceanic tides in the cross-shore direction, a configuration that is essentially one-dimensional. Two-dimensional analytical solutions for groundwater level fluctuation in recent papers are localized in presenting the effect of both oceanic tides and estuarine tides in quadrantal aquifer. A two-dimensional model of groundwater fluctuations in estuarine zone in proposed in this paper. Using complex transform, the two-dimensional flow equation subject to periodic boundary condition is changed into time-independent elliptic problem. Based on Green function method, an analytical solution for groundwater fluctuations in fan-shaped aquifer is derived. The response to of groundwater tidal loading in an estuary and ocean is discussed. The result show that its more extensive application than recent studies.

  19. Long-term forecast: key to groundwater protection.

    Science.gov (United States)

    Gerth, Joachim; Förstner, Ulrich

    2004-01-01

    Groundwater resources are at risk from pollution, climate change and land-management practices. Long-term forecast is a tool to demonstrate future development and to support decisions on measures which can be implemented, controlled and eventually corrected. As the basis for preventive action, a forecast can be viewed as a key to groundwater protection. The soil zone plays a vital role in groundwater protection. Research on soil and groundwater trends, as affected by change of climate and/or land-management practices, is on the agenda. Integrated research is necessary to develop numerical soil-water system models reflecting all relevant transport processes at various scales. Even relatively simple problems like forecasting pollutant release from contaminated materials are difficult to resolve. Batch tests may be sufficient in low-risk cases. At higher risk when contaminated substrates are chosen for deposition on a large scale, a thorough characterization of the materials is necessary covering all aspects of stability and possible changes of the environment.

  20. Thermal footprints in groundwater of central European cities

    Science.gov (United States)

    Bayer, P.; Menberg, K.; Blum, P.

    2014-12-01

    Atmospheric thermal pollution in densely populated areas is recognized as a severe problem with consequences for human health, and considerable efforts are being taken to mitigate heat stress in cities. However, anthropogenic activities also influence the thermal environment beneath the ground level, with commonly growing temperatures that affect groundwater ecology and geothermal use efficiency. In our work, we identify the controlling mechanisms for the long-term evolution of such urban heat islands. The shallow groundwater temperatures in several central European cities such as Cologne, Karlsruhe, Munich, Berlin and Zurich were mapped at high spatial and temporal resolution. Thermal anomalies were found to be highly heterogeneous with local hot spots showing temperatures of more than 20°C. Accordingly, these urban regions show a considerable groundwater warming in comparison to undisturbed temperatures of 8-11°C. Examination of potential heat sources by analytical modelling reveals that increased ground surface temperatures and basements of buildings act as dominant drivers for the anthropogenic heat input into the groundwater. The factors are revealed to be case-specific and they may have pronounced local or regional effects. Typical local factors are for example buried district heating networks. In selected cities we find that the average urban heat flux is around one order of magnitude higher than the elevated ground heat flux due to recent climate change. Additionally, such as observed in Zurich, naturally controlled temperature variations can be substantial and they are shown to wash out anthropogenic thermal footprints.