WorldWideScience

Sample records for vi design conditions

  1. ALTERATION OF U(VI)-PHASES UNDER OXIDIZING CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    A.P. Deditius; S. Utsunomiya; R.C. Ewing

    2006-02-21

    Uranium-(VI) phases are the primary alteration products of the UO{sub 2} in spent nuclear fuel and the UO{sub 2+x}, in natural uranium deposits. The U(VI)-phases generally form sheet structures of edge-sharing UO{sub 2}{sup 2+} polyhedra. The complexity of these structures offers numerous possibilities for coupled-substitutions of trace metals and radionuclides. The incorporation of radionuclides into U(VI)-structures provides a potential barrier to their release and transport in a geologic repository that experiences oxidizing conditions. In this study, we have used natural samples of UO{sub 2+x}, to study the U(VI)-phases that form during alteration and to determine the fate of the associated trace elements.

  2. Technology-derived storage solutions for stabilizing insulin in extreme weather conditions I: the ViViCap-1 device.

    Science.gov (United States)

    Pfützner, Andreas; Pesach, Gidi; Nagar, Ron

    2017-06-01

    Injectable life-saving drugs should not be exposed to temperatures 30°C/86°F. Frequently, weather conditions exceed these temperature thresholds in many countries. Insulin is to be kept at 4-8°C/~ 39-47°F until use and once opened, is supposed to be stable for up to 31 days at room temperature (exception: 42 days for insulin levemir). Extremely hot or cold external temperature can lead to insulin degradation in a very short time with loss of its glucose-lowering efficacy. Combined chemical and engineering solutions for heat protection are employed in ViViCap-1 for disposable insulin pens. The device works based on vacuum insulation and heat consumption by phase-change material. Laboratory studies with exposure of ViViCap-1 to hot outside conditions were performed to evaluate the device performance. ViViCap-1 keeps insulin at an internal temperature change process and 'recharges' the device for further use. ViViCap-1 performed within its specifications. The small and convenient device maintains the efficacy and safety of using insulin even when carried under hot weather conditions.

  3. Berhting Facilities Development Design for Makassar Main Naval VI Indonesian Navy

    OpenAIRE

    Rachman, Taufiqur

    2016-01-01

    In agenda of preparing Makassar Main Naval Base VI upgrading to be Middle Region Fleet Command and Military Sealift Command Position as homeport for KRI Ahmad Yani class frigate and KRI Makassar class LPD has berthing facilities llimited condition. Therefore, they propose a berthing facilities development program to Naval Headquarters to build a new facilities in Makassar. To get a maximum result from limited site with enviromental design condition, in designing lay out of development, an...

  4. Box-Behnken experimental design for chromium(VI) ions removal by bacterial cellulose-magnetite composites.

    Science.gov (United States)

    Stoica-Guzun, Anicuta; Stroescu, Marta; Jinga, Sorin Ion; Mihalache, Nicoleta; Botez, Adriana; Matei, Cristian; Berger, Daniela; Damian, Celina Maria; Ionita, Valentin

    2016-10-01

    In this study bacterial cellulose-magnetite composites were synthesised for the removal of chromium(VI) from aqueous solutions. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis and X-ray Photoelectron Spectroscopy (XPS) were used to characterize the bacterial cellulose-magnetite composites and to reveal the uniform dispersion of nanomagnetite in the BC matrix. Magnetic properties were also measured to confirm the magnetite immobilization on bacterial cellulose membrane. The effects of initial Cr(VI) concentration, solution pH and solid/liquid ratio upon chromium removal were examined using the statistical Box-Behnken Design. Because of the possibility of magnetite dissolution during chromium(VI) adsorption, the degree of iron leaching was also analysed in the same conditions as Cr(VI) adsorption. From the factors affecting chromium(VI) adsorption the most important was solution pH. The highest Cr(VI) removal efficiency was observed at pH 4, accompanied by the lowest iron leaching in the solution. The adsorption experiments also indicated that the adsorption process of chromium(VI) is well described by Freundlich adsorption model. Our results proved that the BC-magnetite composites could be used for an efficient removal of chromium(VI) from diluted solutions with a minimum magnetite dissolution during operation. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Transitional DDES computations of the NREL Phase-VI rotor in axial flow conditions

    DEFF Research Database (Denmark)

    Sørensen, Niels N.; Schreck, Scott

    2014-01-01

    In the present article we describe CFD simulations of the well known NREL Phase-VI rotor in axial flow conditions using a newly developed technique of combining turbulence modeling by the Delayed Detached Eddy Simulation (DDES) technique with laminar/turbulent transition modeling by a correlation...

  6. Removal of Cr(VI) by surfactant modified Auricularia auricula spent substrate: biosorption condition and mechanism.

    Science.gov (United States)

    Dong, Liying; Jin, Yu; Song, Tao; Liang, Jinsong; Bai, Xin; Yu, Sumei; Teng, Chunying; Wang, Xin; Qu, Juanjuan; Huang, Xiaomei

    2017-07-01

    Auricularia auricula spent substrate (AASS) modified by didodecyldimethylammonium bromide(DDAB) was used as adsorbent to remove Cr(VI) from aqueous solution. Based on a single-factor experiment and response surface methodology, the optimal conditions were adsorbent dosage of 1.5 g/L, pH value of 4.0, initial Cr(VI) concentration of 19 mg/L, temperature of 25 °C, biosorption time of 120 min, rotational speed of 150 r/min, respectively, under which biosorption capacity could reach 12.16 mg/g compared with unmodified AASS (6.058 mg/g). DDAB modification could enlarge the specific surface area and porous diameter of the adsorbents, and supply hydrophilic and hydrophobic groups capable of adsorbing at the interfaces. In addition, DDAB increased ionic exchange and complex formation demonstrated by variations of elemental contents, shifts of carboxyl, amine groups, hydroxyl, alkyl chains, and phosphate groups as well as the crystal structure of the Cr-O compounds. Variations of peaks and energy in XPS analysis also testified the reduction of Cr(VI) to Cr(III).The biosorption behavior of modified AASS was in line with Langmuir and Freundlich isotherm equation. The final regeneration efficiency was 62.33% after three biosorption-desorption cycles. Apparently, DDBA is a eximious modifier and DDBA-modified AASS was very efficient for Cr(VI) removal.

  7. Human factors in organizational design and management VI

    NARCIS (Netherlands)

    Vink, P.; Koningsveld, E.A.P.; Dhondt, S.

    1998-01-01

    This book contains proceedings of the Sixth International Symposium on Human Factors in Organizational Design and Management held in The Hague, The Netherlands, August 19-22, 1998. The Symposium was sponsored jointly by the International Ergonomics Society, the Dutch Ergonomics Society, NIA TNO and

  8. Removal of chromium (VI) by acid-washed zero-valent iron under various groundwater geochemistry conditions.

    Science.gov (United States)

    Lai, Keith C K; Lo, Irene M C

    2008-02-15

    The hexavalent chromium (Cr(VI)) removal capacity of acid-washed zerovalent iron (AW-Fe0) was evaluated under different groundwater geochemistry conditions through column experiments. It was found that each gram of the AW-Fe0 could remove 0.65-1.76 mg of Cr(VI) from synthetic groundwater in the absence of bicarbonate (HCO3-), magnesium and/or calcium ions. Groundwater geochemistry was found to exert various degrees of impact on Cr(VI) removal by the AW-Fe0, in which HCO3- alone gave the mildest impact whereas the copresence of calcium and HCO3- exerted the greatest impact In comparison with the unwashed Fe0, the AW-Fe0 showed a poorer Cr(VI) removal capacity and was also more susceptible to the influence of the dissolved groundwater constituents on Cr(VI) removal,thereby indicating the unsuitability of using AW-Fe0 in permeable reactive barriers for remediation of Cr(VI)-contaminated groundwater. On the AW-Fe0 surface, where the indigenous iron precipitates were almost erased, trivalent chromium including chromium (III) oxides, hydroxides, and oxyhydroxides in irregular strip, chick footmark-liked or boulder-liked forms as well as Cr(III)-Cr(VI) mixed oxides were detected.

  9. Chromium isotopic fractionation during Cr(VI) reduction by Bacillus sp. under aerobic conditions.

    Science.gov (United States)

    Xu, Fen; Ma, Teng; Zhou, Lian; Hu, Zhifang; Shi, Liu

    2015-07-01

    This study investigated the fractionation of chromium isotopes during chromium reduction by Bacillus sp. under aerobic condition, variable carbon source (glucose) concentration (0, 0.1, 1, 2.5 and 10mM), and incubation temperatures (4, 15, 25 and 37°C). The results revealed that the δ(53)Cr values in the residual Cr(VI) increased with the degree of Cr reduction, and followed a Rayleigh fractionation model. The addition of glucose only slightly affected cell-specific Cr(VI) reduction rates (cSRR). However, the value of ε (2.00±0.21‰) in the experiments with different concentrations of glucose (0.1, 1, 2.5 and 10mM) was smaller than that from the experiment without glucose (3.74±0.16‰). The results indicated that the cell-specific reduction rate is not the sole control on the degree of isotopic fractionation, and different metabolic pathways would result in differing degrees of Cr isotopic fractionation. The cSRR decreased with decreasing temperature, showing that the values of ε were 7.62±0.36‰, 4.59±0.28‰, 3.09±0.16‰ and 1.99±0.23‰ at temperatures of 4, 15, 25 and 37°C, respectively. It shown that increasing cSRR linked to decreasing fractionations has been associated with increasing temperatures. Overall, our results revealed that temperature is a primary factor affecting Cr isotopic fractionation under microbial actions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Chromium released from leather - I: exposure conditions that govern the release of chromium(III) and chromium(VI).

    Science.gov (United States)

    Hedberg, Yolanda S; Lidén, Carola; Odnevall Wallinder, Inger

    2015-04-01

    Approximately 1-3% of the adult population in Europe is allergic to chromium (Cr). A new restriction in REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) based on the ISO 17075 standard has recently been adopted in the EU to limit Cr(VI) in consumer and occupational leather products. The aim of this study was to critically assess key experimental parameters in this standard on the release of Cr(III) and Cr(VI) and their relevance for skin exposure. Four differently tanned, unfinished, leather samples were systematically investigated for their release of Cr(III) and Cr(VI) in relation to surface area, key exposure parameters, temperature, ultraviolet irradiation, and time. Although the total release of Cr was largely unaffected by all investigated parameters, except exposure duration and temperature, the Cr oxidation state was highly dynamic, with reduced amounts of released Cr(VI) with time, owing to the simultaneous release of reducing agents from the leather. Significantly more Cr(III) than Cr(VI) was released from the Cr-tanned leather for all conditions tested, and it continued to be released in artificial sweat up to at least 1 week of exposure. Several parameters were identified that influenced the outcome of the ISO 17075 test. © 2015 The Authors. Contact Dermatitis published by John Wiley & Sons Ltd.

  11. Chromium released from leather – I: exposure conditions that govern the release of chromium(III) and chromium(VI)

    Science.gov (United States)

    Hedberg, Yolanda S; Lidén, Carola; Odnevall Wallinder, Inger

    2015-01-01

    Background Approximately 1–3% of the adult population in Europe is allergic to chromium (Cr). A new restriction in REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) based on the ISO 17075 standard has recently been adopted in the EU to limit Cr(VI) in consumer and occupational leather products. Objectives The aim of this study was to critically assess key experimental parameters in this standard on the release of Cr(III) and Cr(VI) and their relevance for skin exposure. Material and methods Four differently tanned, unfinished, leather samples were systematically investigated for their release of Cr(III) and Cr(VI) in relation to surface area, key exposure parameters, temperature, ultraviolet irradiation, and time. Results Although the total release of Cr was largely unaffected by all investigated parameters, except exposure duration and temperature, the Cr oxidation state was highly dynamic, with reduced amounts of released Cr(VI) with time, owing to the simultaneous release of reducing agents from the leather. Significantly more Cr(III) than Cr(VI) was released from the Cr-tanned leather for all conditions tested, and it continued to be released in artificial sweat up to at least 1 week of exposure. Conclusions Several parameters were identified that influenced the outcome of the ISO 17075 test. PMID:25653094

  12. Octarellin VI: using rosetta to design a putative artificial (β/α8 protein.

    Directory of Open Access Journals (Sweden)

    Maximiliano Figueroa

    Full Text Available The computational protein design protocol Rosetta has been applied successfully to a wide variety of protein engineering problems. Here the aim was to test its ability to design de novo a protein adopting the TIM-barrel fold, whose formation requires about twice as many residues as in the largest proteins successfully designed de novo to date. The designed protein, Octarellin VI, contains 216 residues. Its amino acid composition is similar to that of natural TIM-barrel proteins. When produced and purified, it showed a far-UV circular dichroism spectrum characteristic of folded proteins, with α-helical and β-sheet secondary structure. Its stable tertiary structure was confirmed by both tryptophan fluorescence and circular dichroism in the near UV. It proved heat stable up to 70°C. Dynamic light scattering experiments revealed a unique population of particles averaging 4 nm in diameter, in good agreement with our model. Although these data suggest the successful creation of an artificial α/β protein of more than 200 amino acids, Octarellin VI shows an apparent noncooperative chemical unfolding and low solubility.

  13. Cr(VI) transport via a supported ionic liquid membrane containing CYPHOS IL101 as carrier: system analysis and optimization through experimental design strategies.

    Science.gov (United States)

    Rodríguez de San Miguel, Eduardo; Vital, Xóchitl; de Gyves, Josefina

    2014-05-30

    Chromium(VI) transport through a supported liquid membrane (SLM) system containing the commercial ionic liquid CYPHOS IL101 as carrier was studied. A reducing stripping phase was used as a mean to increase recovery and to simultaneously transform Cr(VI) into a less toxic residue for disposal or reuse. General functions which describe the time-depending evolution of the metal fractions in the cell compartments were defined and used in data evaluation. An experimental design strategy, using factorial and central-composite design matrices, was applied to assess the influence of the extractant, NaOH and citrate concentrations in the different phases, while a desirability function scheme allowed the synchronized optimization of depletion and recovery of the analyte. The mechanism for chromium permeation was analyzed and discussed to contribute to the understanding of the transfer process. The influence of metal concentration was evaluated as well. The presence of different interfering ions (Ca(2+), Al(3+), NO3(-), SO4(2-), and Cl(-)) at several Cr(VI): interfering ion ratios was studied through the use of a Plackett and Burman experimental design matrix. Under optimized conditions 90% of recovery was obtained from a feed solution containing 7mgL(-1) of Cr(VI) in 0.01moldm(-3) HCl medium after 5h of pertraction. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Uranium(VI) retention by Ca-bentonite under (hyper)alkaline conditions

    Energy Technology Data Exchange (ETDEWEB)

    Philipp, Thimo; Schmeide, Katja [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

    2017-06-01

    The sorption behavior of U(VI) on Ca-bentonite was studied in saline, (hyper)alkaline solution via batch experiments. At pH 8.5-9.5 sorption is low in the presence of CO{sub 2} due to the formation of weakly sorbing uranyl carbonate species, which have been observed to dominate speciation up to pH 10 by time-resolved laser-induced fluorescence spectroscopy (TRLFS). In the pH region 10-12, U(VI) retention is almost complete. The retention can either be attributed to strongly sorbing uranyl hydroxo complexes or to a partial precipitation of uranium due to an altered solubility of U(VI) induced by ions leached out of the bentonite.

  15. New drainage tunnel of the tunnel Višňové - design and excavation

    Science.gov (United States)

    Jurík, Igor; Grega, Ladislav; Valko, Jozef; Janega, Peter

    2017-09-01

    The actual pilot tunnel dated to the period of geological and hydrogeological survey, is designed as a part of the tunnel Višňové, which is located at the section of the D1 motorway Lietavská Lúčka - Višňové - Dubná Skala in Slovakia. Drainage tunnel will be used for the drainage of the main tunnel tubes, where the maximum inflow from the eastern portal is greater than 250 l.s-1. Overlapping of the initial pilot tunnel with the profile of the southern tunnel tube led to the demolition of the portal sections of the pilot tunnel during the excavation of main tunnel tubes. These sections were replaced by new drainage tunnels, with the lengths of 288.0 meters from west portal and 538.0 meters from eastern portal, to ensure access from both portals. The new drainage tunnel is excavated under the level of the two main tunnel tubes. Drainage pipes with a diameter of 250 mm will be installed from cleaning niches in the main tunnel tubes to the new drainage tunnel.

  16. Cyclopentadienyl molybdenum(II/VI) N-heterocyclic carbene complexes: Synthesis, structure, and reactivity under oxidative conditions

    KAUST Repository

    Li, Shenyu

    2010-04-26

    A series of N-heterocyclic carbene (NHC) complexes CpMo(CO) 2(NHC)X (NHC = IMe = 1,3-dimethylimidazol-2-ylidene, X = Br, 1; NHC = 1,3-dipropylimidazol-2-ylidene, X = Br, 2; NHC = IMes = 1,3-bis(2,4,6- trimethylphenyl)imidazol-2-ylidene, X = Br, 3; NHC = IBz = 1,3-dibenzylimidazol- 2-ylidene, X = Br, 4a, and X = Cl, 4b; NHC = 1-methyl-3-propylimidazol-2- ylidene, X = Br, 5) and [CpMo(CO)2(IMes)(CH3CN)][BF 4] (6) have been synthesized and fully characterized. The stability of metal-NHC ligand bonds in these compounds under oxidative conditions has been investigated. The thermally stable Mo(VI) dioxo NHC complex [CpMoO 2(IMes)][BF4] (9) has been isolated by the oxidation of the ionic complex 6 by TBHP (tert-butyl hydrogen peroxide). Complex 6 can be applied as a very active (TOFs up to 3400 h-1) and selective olefin epoxidation catalyst. While under oxidative conditions (in the presence of TBHP), compounds 1-5 decompose into imidazolium bromide and imidazolium polyoxomolybdate. The formation of polyoxomolybdate as oxidation products had not been observed in a similar epoxidation catalyzed by Mo(II) and Mo(VI) complexes. DFT studies suggest that the presence of Br- destabilizes the CpMo(VI) oxo NHC carbene species, consistent with the experimental observations. © 2010 American Chemical Society.

  17. Understanding the role of clay minerals in the chromium(VI) bioremoval by Pseudomonas aeruginosa CCTCC AB93066 under growth condition: microscopic, spectroscopic and kinetic analysis.

    Science.gov (United States)

    Kang, Chunxi; Wu, Pingxiao; Li, Yuewu; Ruan, Bo; Li, Liping; Tran, Lytuong; Zhu, Nengwu; Dang, Zhi

    2015-11-01

    Laboratory batch experiments were conducted to investigate the role of clay minerals, e.g., kaolinite and vermiculite, in microbial Cr(VI) reduction by Pseudomonas aeruginosa under growth condition in glucose-amended mediums as a method for treating Cr(VI)-contaminated subsurface environment such as soil. Our results indicated that glucose could acted as an essential electron donor, and clay minerals significantly enhanced microbial Cr(VI) reduction rates by improving the consumption rate of glucose and stimulating the growth and propagation of P. aeruginosa. Cr(VI) bioreduction by both free cells and clay minerals-amended cells followed the pseudo-first-order kinetic model, with the latter one fitting better. The mass balance analyses and X-ray photoelectron spectroscopy analysis found that Cr(VI) was reduced to Cr(III) and the adsorption of total chromium on clay minerals-bacteria complex was small, implying that Cr(VI) bioremoval was not mainly due to the adsorption of Cr(VI) onto cells or clay minerals or clay minerals-cells complex but mainly due to the Cr(VI) reduction capacity of P. aeruginosa under the experimental conditions studied (e.g., pH 7). Atomic force microscopy revealed that the addition of clay minerals (e.g. vermiculite) decreased the surface roughness of Cr(VI)-laden cells and changed the cell morphology and dimension. Fourier transform infrared spectroscopy revealed that organic matters such as aliphatic species and/or proteins played an important role in the combination of cells and clay minerals. Scanning electron microscopy confirmed the attachment of cells on the surface of clay minerals, indicating that clay minerals could provide a microenvironment to protect cells from Cr(VI) toxicity and serve as growth-supporting materials. These findings manifested the underlying influence of clay minerals on microbial reduction of Cr(VI) and gave an understanding of the interaction between pollutants, the environment and the biota.

  18. Functionalized Sugarcane Bagasse for U(VI) Adsorption from Acid and Alkaline Conditions.

    Science.gov (United States)

    Su, Shouzheng; Liu, Qi; Liu, Jingyuan; Zhang, Hongsen; Li, Rumin; Jing, Xiaoyan; Wang, Jun

    2018-01-15

    The highly efficient removal of uranium from mine tailings effluent, radioactive wastewater and enrichment from seawater is of great significance for the development of nuclear industry. In this work, we prepared an efficient U(VI) adsorbent by EDTA modified sugarcane bagasse (MESB) with a simple process. The prepared adsorbent preserves high adsorptive capacity for UO 2 2+ (pH 3.0) and uranyl complexes, such as UO 2 (OH) + , (UO 2 ) 2 (OH) 2 2+ and (UO 2 ) 3 (OH) 5 + (pH 4.0 and pH 5.0) and good repeatability in acidic environment. The maximum adsorption capacity for U(VI) at pH 3.0, 4.0 and 5.0 is 578.0, 925.9 and 1394.1 mg/g and the adsorption capacity loss is only 7% after five cycles. With the pH from 3.0 to 5.0, the inhibitive effects of Na + and K + decreased but increased of Mg 2+ and Ca 2+ . MESB also exhibits good adsorption for [UO 2 (CO 3 ) 3 ] 4- at pH 8.3 from 10 mg/L to 3.3 μg/L. Moreover, MESB could effectively extract U(VI) from simulated seawater in the presence of other metals ions. This work provided a general and efficient uranyl enriched material for nuclear industry.

  19. Different biosorption mechanisms of Uranium(VI) by live and heat-killed Saccharomyces cerevisiae under environmentally relevant conditions.

    Science.gov (United States)

    Wang, Tieshan; Zheng, Xinyan; Wang, Xiaoyu; Lu, Xia; Shen, Yanghao

    2017-02-01

    Uranium adsorption mechanisms of live and heat-killed Saccharomyces cerevisiae in different pH values and biomass concentrations were studied under environmentally relevant conditions. Compared with live cells, the adsorption capacity of heat-killed cells is almost one order of magnitude higher in low biomass concentration and highly acidic pH conditions. To explore the mesoscopic surface interactions between uranium and cells, the characteristic of uranium deposition was investigated by SEM-EDX, XPS and FTIR. Biosorption process of live cells was considered to be metabolism-dependent. Under stimulation by uranyl ions, live cells could gradually release phosphorus and reduce uranium from U(VI) to U(IV) to alleviate uranium toxicity. The uranyl-phosphate complexes were formed in scale-like shapes on cell surface. The metabolic detoxification mechanisms such as reduction and "self-protection" are of significance to the migration of radionuclides. In the metabolism-independent biosorption process of heat-killed cells: the cells cytomembrane was damaged by autoclaving which led to the free diffusion of phosphorous from intracellular, and the rough surface and nano-holes indicated that the dead cells provided larger contact area to precipitate U(VI) as spherical nano-particles. The high biosorption capacity of heat-killed cells makes it become a suitable biological adsorbent for uranium removal. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Preparation, characterization, uranium (VI) biosorption models, and conditions optimization by response surface methodology (RSM) for amidoxime-functionalized marine fungus materials

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xuechun; Gao, Yang; Jiang, Min; He, Dianxiong; Liao, Sen; Hou, Dan; Yan, Xueming; Long, Wei; Wu, Yaxin; Tan, Ni [Univ. of South China, Hengyang (China). School of Chemistry and Chemical Engineering

    2017-08-01

    Amidoxime-functionalized marine fungus Fusarium sp. ZZF51 (ZGDA) was synthesized and studied to adsorb uranium (VI) from the aqueous solution. Different instrumental techniques such as FTIR, SEM, and TGA were employed for the characterization of the manufactured materials, and theirs ability of removal uranium (VI) was optimized using RSM. The experimental results showed the maximum adsorption capacity for the synthesized materials was 230.78 mg g{sup -1} at the following optimization conditions: S-L ratio 150 mg L{sup -1}, pH 5.13, uranium (VI) initial concentration 40 mg L{sup -1}, and equilibrium time 122.40 min. More than 85% of the absorbed uranium (VI) could be desorbed by 0.5 or 1.0 mol L{sup -1} HCl, and the modified mycelium could be reused at least five times. The thermodynamic experimental data of adsorption uranium (VI) could fit better with Langmuir and Freundlich isotherms models, and the pseudo-second-order model was better to interpret the kinetics process. The modified fungus materials exhibited the better sorption capacity for uranium (VI) in comparison with raw biomass should be attributed to the strong chelation of amidoxime to uranium (VI) ions.

  1. Hot conditioning equipment conceptual design report

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, F.W., Westinghouse Hanford

    1996-08-06

    This report documents the conceptual design of the Hot Conditioning System Equipment. The Hot conditioning System will consist of two separate designs: the Hot Conditioning System Equipment; and the Hot Conditioning System Annex. The Hot Conditioning System Equipment Design includes the equipment such as ovens, vacuum pumps, inert gas delivery systems, etc.necessary to condition spent nuclear fuel currently in storage in the K Basins of the Hanford Site. The Hot Conditioning System Annex consists of the facility of house the Hot Conditioning System. The Hot Conditioning System will be housed in an annex to the Canister Storage Building. The Hot Conditioning System will consist of pits in the floor which contain ovens in which the spent nuclear will be conditioned prior to interim storage.

  2. A Multilevel Consideration of Service Design Conditions

    DEFF Research Database (Denmark)

    Karpen, Ingo; Gemser, Gerda; Calabretta, Giulia

    2017-01-01

    Purpose: The purpose of this paper is to advance the current understanding of organisational conditions that facilitate service design. Specifically, the focus is on organisational capabilities, interactive practices and individual abilities as units of analysis across service system levels....... Grounded in design principles, the paper conceptualises and delineates illustrative service design conditions and introduces a respective service design capability-practice-ability (CPA) portfolio. In doing so, an emerging microfoundations perspective in the context of service design is advanced. Design....../methodology/approach: Conceptual paper. Findings: This paper identifies and delineates a CPA that contributes to service design and ultimately customer experiences. The service design CPA consists of six illustrative constellations of service design capabilities, practices and abilities, which operate on different organisational...

  3. Designing and implementing a Quality Broker: the GeoViQua experience

    Science.gov (United States)

    Papeschi, Fabrizio; Bigagli, Lorenzo; Masò, Joan; Nativi, Stefano

    2014-05-01

    GeoViQua (QUAlity aware VIsualisation for the Global Earth Observation System of Systems) is an FP7 project aiming at complementing the Global Earth Observation System of Systems (GEOSS) with rigorous data quality specifications and quality-aware capabilities, in order to improve reliability in scientific studies and policy decision-making. GeoViQua main scientific and technical objective is to enhance the GEOSS Common Infrastructure (GCI) providing the user community with innovative quality-aware search and visualization tools, which will be integrated in the GEOPortal, as well as made available to other end-user interfaces. To this end, GeoViQua will promote the extension of the current standard metadata for geographic information with accurate and expressive quality indicators. Employing and extending several ISO standards such as 19115, 19157 and 19139, a common set of data quality indicators has been selected to be used within the project. The resulting work, in the form of a data model, is expressed in XML Schema Language and encoded in XML. Quality information can be stated both by data producers and by data users, actually resulting in two conceptually distinct data models, the Producer Quality model and the User Quality model (or User Feedback model). GeoViQua architecture is built on the brokering approach successfully experimented within the EuroGEOSS project and realized by the GEO DAB (Discovery and Access Broker) which is part of the GCI. The GEO DAB allows for harmonization and distribution in a transparent way for both users and data providers. This way, GeoViQua can effectively complement and extend the GEO DAB obtaining a Quality augmentation Broker (DAB-Q) which plays a central role in ensuring the consistency of the Producer and User quality models. The GeoViQua architecture also includes a Feedback Catalog, a particular service brokered by the DAB-Q which is dedicated to the storage and discovery of user feedbacks. A very important issue

  4. Ethylenediamine grafted to graphene oxide@Fe3O4 for chromium(VI decontamination: Performance, modelling, and fractional factorial design.

    Directory of Open Access Journals (Sweden)

    Xinjiang Hu

    Full Text Available A method for grafting ethylenediamine to a magnetic graphene oxide composite (EDA-GO@Fe3O4 was developed for Cr(VI decontamination. The physicochemical properties of EDA-GO@Fe3O4 were characterized using HRTEM, EDS, FT-IR, TG-DSC, and XPS. The effects of pH, sorbent dose, foreign anions, time, Cr(VI concentration, and temperature on decontamination process were studied. The solution pH can largely affect the decontamination process. The pseudo-second-order model is suitable for being applied to fit the adsorption processes of Cr(VI with GO@Fe3O4 and EDA-GO@Fe3O4. The intra-particle diffusion is not the rate-controlling step. Isotherm experimental data can be described using the Freundlich model. The effects of multiple factors on the Cr(VI decontamination was investigated by a 25-1 fractional factorial design (FFD. The adsorption process can significantly be affected by the main effects of A (pH, B (Cr(VI concentration, and E (Adsorbent dose. The combined factors of AB (pH × Cr(VI concentration, AE (pH × Adsorbent dose, and BC (Cr(VI concentration × Temperature had larger effects than other factors on Cr(VI removal. These results indicated that EDA-GO@Fe3O4 is a potential and suitable candidate for treatment of heavy metal wastewater.

  5. Wind conditions for wind turbine design

    Energy Technology Data Exchange (ETDEWEB)

    Maribo Pedersen, B.

    1999-04-01

    Delegates from Europe and USA attended the meeting and discussed general aspects of wind conditions for wind turbine design. The subjects and the presented papers covered a very broad range of aspects of wind conditions and related influence on the wind turbine. (EHS)

  6. Signal conditioning circuitry design for instrumentation systems.

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Cory A.

    2012-01-01

    This report details the current progress in the design, implementation, and validation of the signal conditioning circuitry used in a measurement instrumentation system. The purpose of this text is to document the current progress of a particular design in signal conditioning circuitry in an instrumentation system. The input of the signal conditioning circuitry comes from a piezoresistive transducer and the output will be fed to a 250 ksps, 12-bit analog-to-digital converter (ADC) with an input range of 0-5 V. It is assumed that the maximum differential voltage amplitude input from the sensor is 20 mV with an unknown, but presumably high, sensor bandwidth. This text focuses on a specific design; however, the theory is presented in such a way that this text can be used as a basis for future designs.

  7. A highly selective sorbent for removal of Cr(VI) from aqueous solutions based on Fe{sub 3}O{sub 4}/poly(methyl methacrylate) grafted Tragacanth gum nanocomposite: Optimization by experimental design

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi, Susan, E-mail: ssadeghi@birjand.ac.ir; Rad, Fatemeh Alavi; Moghaddam, Ali Zeraatkar

    2014-12-01

    In this work, poly(methyl methacrylate) grafted Tragacanth gum modified Fe{sub 3}O{sub 4} magnetic nanoparticles (P(MMA)-g-TG-MNs) were developed for the selective removal of Cr(VI) species from aqueous solutions in the presence of Cr(III). The sorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), a vibrating sample magnetometer (VSM), and thermo-gravimetric analysis (TGA). A screening study on operational variables was performed using a two-level full factorial design. Based on the analysis of variance (ANOVA) with 95% confidence limit, the significant variables were found. The central composite design (CCD) has also been employed for statistical modeling and analysis of the effects and interactions of significant variables dealing with the Cr(VI) uptake process by the developed sorbent. The predicted optimal conditions were situated at a pH of 5.5, contact time of 3.4 h, and 3.0 g L{sup −1} dose. The Langmuir, Freundlich, and Temkin isotherm models were used to describe the equilibrium sorption of Cr(VI) by the absorbent, and the Langmuir isotherm showed the best concordance as an equilibrium model. The adsorption process was followed by a pseudo-second-order kinetic model. Thermodynamic investigations showed that the biosorption process was spontaneous and exothermic. - Highlights: • Fe3O4 nanoparticles were modified with Poly(methyl methacrylate) grafted Tragacanth gum • P(MMA)-g-TG -MNPs can preferentially adsorb Cr(VI) in the presence of Cr(III) • The effects of operational parameters on Cr(VI) removal were evaluated by RSM • Adsorption mechanism, kinetics, and isotherm have been explored • The sorbent was successfully used to remove Cr(VI) from different water samples.

  8. Chromium(VI)-resistant yeast isolated from a sewage treatment plant receiving tannery wastes.

    Science.gov (United States)

    Baldi, F; Vaughan, A M; Olson, G J

    1990-01-01

    A Cr(VI)-resistant yeast, designated strain DBVPG 6502, was isolated from a sewage treatment plant receiving wastes from tannery industries in Italy. The strain was tentatively identified as a species of Candida based on morphological and physiological analyses. This strain was highly resistant to Cr(VI) when compared with eight other yeast species, growing at Cr(VI) concentrations of up to 500 micrograms/ml (10 mM). This resistance was constitutive. The Cr(VI)-resistant yeast did not reduce Cr(VI) to Cr(III) species under aerobic conditions. The yeast showed very little accumulation of Cr(VI). Consequently, the mechanism of resistance of the yeast to Cr(VI) appears to involve reduced accumulation of Cr, as has been shown in Cr(VI)-resistant bacteria. Images PMID:2339879

  9. Estimating the angle of attack from blade pressure measurements on the NREL Phase VI rotor using a free wake vortex model: axial conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sant, Tonio [Delft Univ. of Technology, Faculty of Aerospace Engineering, Delft (Netherlands); Malta Univ., Mechanical Engineering Dept., Msida (Malta); Kuik, Gijs van; Bussel, G.J.W. van [Delft Univ. of Technology, Faculty of Aerospace Engineering, Delft (Netherlands)

    2006-07-01

    Blade element momentum (BEM) methods are still the most common methods used for predicting the aerodynamic loads during the aeroelastic design of wind turbine blades. However, their accuracy is limited by the availability of reliable aerofoil data. Owing to the 3D nature of the flow over wind turbine blades, the aerofoil characteristics will vary considerably from the 2D aerofoil characteristics, especially at the inboard sections of the blades. Detailed surface pressure measurements on the blade surfaces may be used to derive more realistic aerofoil data. However, in doing so, knowledge of the angle of attack distributions is required. This study presents a method in which a free wake vortex model is used to derive such distributions for the NREL Phase VI wind turbine under different operating conditions. The derived free wake geometry solutions are plotted together with the corresponding wake circulation distribution. These plots provide better insight into how circulation formed at the blades is eventually diffused into the wake. The free wake model is described and its numerical behaviour is examined. (Author)

  10. MOOCS AS NEW CONDITIONS FOR INSTRUCTIONAL DESIGN

    DEFF Research Database (Denmark)

    Buhl, Mie; Andreasen, Lars Birch; Karanam, Pushpanadham

    individuals and societies with the skills, perspectives, knowledge and values to live and work. Today, as the world becomes increasingly interconnected, interdependent and globalized, higher education is critical for the achievement of economic, political and social development. Without adequate higher...... education and research institutions and a critical mass of skilled and educated people, no society can ensure genuine sustainable development (UNESCO, 1998). Information and Communication Technologies have entailed changes in the conditions for teaching and learning. New technologies do not in themselves...... of instructional design, educational design, and learning design, which have different roots, but in their current use they may overlap and offer new possibilities of thinking educational development (Mor et al., 2015). The paper will highlight the changing landscape of learning in higher education in Europe...

  11. Rational Ligand Design for U(VI) and Pu(IV)

    Energy Technology Data Exchange (ETDEWEB)

    Szigethy, Geza [Univ. of California, Berkeley, CA (United States)

    2009-08-12

    Nuclear power is an attractive alternative to hydrocarbon-based energy production at a time when moving away from carbon-producing processes is widely accepted as a significant developmental need. Hence, the radioactive actinide power sources for this industry are necessarily becoming more widespread, which is accompanied by the increased risk of exposure to both biological and environmental systems. This, in turn, requires the development of technology designed to remove such radioactive threats efficiently and selectively from contaminated material, whether that be contained nuclear waste streams or the human body. Raymond and coworkers (University of California, Berkeley) have for decades investigated the interaction of biologically-inspired, hard Lewis-base ligands with high-valent, early-actinide cations. It has been established that such ligands bind strongly to the hard Lewis-acidic early actinides, and many poly-bidentate ligands have been developed and shown to be effective chelators of actinide contaminants in vivo. Work reported herein explores the effect of ligand geometry on the linear U(IV) dioxo dication (uranyl, UO2 2+). The goal is to utilize rational ligand design to develop ligands that exhibit shape selectivity towards linear dioxo cations and provides thermodynamically favorable binding interactions. The uranyl complexes with a series of tetradentate 3-hydroxy-pyridin-2-one (3,2-HOPO) ligands were studied in both the crystalline state as well as in solution. Despite significant geometric differences, the uranyl affinities of these ligands vary only slightly but are better than DTPA, the only FDA-approved chelation therapy for actinide contamination. The terepthalamide (TAM) moiety was combined into tris-beidentate ligands with 1,2- and 3,2-HOPO moieties were combined into hexadentate ligands whose structural preferences and solution thermodynamics were measured with the uranyl cation. In addition to achieving coordinative

  12. Display design strategy for condition monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Paulsen, Jette Lundtang

    2002-08-15

    This report describes the development of a strategy for interface design for process plants. The strategy is based on methods from risk analysis to elicit the problems in the plant. In the present work the strategy has been used on a condenser and a high pressure preheater. The test of the strategy in this work focuses on the condition of systems, but could as well focus on functions of the plant. The report further describes from which sources knowledge about the plant can be extracted. A display for supervision of the condenser condition has been tested on a nuclear power plant, a gas fired power plant and the HAMBO simulator(HAMlab BOiling water reactor). A pre-heater display is still under development, but has been tested on a PC display, replaying data collected at the HAMBO simulator. (Author)

  13. U(VI) complexation with selected flavonoids investigated by absorption and emission spectroscopy at light acidic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, Alix; Geipel, Gerhard [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry

    2017-06-01

    Flavonoids are secondary plant compounds and have important properties. Beside their antioxidant activity and effects as enzyme inhibitors, they can bind metals ions. The possible release of flavonoids from the root into the soil can affect the migration of radionuclides in the biological and geological environment. In this work, the complexation behavior of selected flavonols and a flavonol glycoside towards U(VI) were spectroscopically investigated and the corresponding complex stability constants were determined.

  14. Evaluation of the effects of various culture condition on Cr (VI)reduction by Shewanella oneidensis MR-1 in a novel high-throughputmini-bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yinjie J.; Laidlaw, David; Gani, Kishen; Keasling, Jay D.

    2006-03-16

    The growth and Cr(VI) reduction by Shewanella oneidensisMR-1 was examined using a mini-bioreactor system that independentlymonitors and controls pH, dissolved oxygen, and temperature for each ofits 24, 10-mL reactors. Independent monitoring and control of eachreactor in the cassette allows the exploration of a matrix ofenvironmental conditions known to influence S. oneidensis chromiumreduction. S. oneidensis MR-1 grew in minimal medium without amino acidor vitamin supplementation under aerobic conditions but required serineand glycine supplementation under anaerobic conditions. Growth wasinhibited by dissolved oxygen concentrations>80 percent. Lactatetransformation to acetate was enhanced by low concentration of dissolvedoxygen during the logarithmic growth phase. Between 11 and 35oC, thegrowth rate obeyed the Arrhenius reaction rate-temperature relationship,with a maximum growth rate occurring at 35oC. S. oneidensis MR-1 was ableto grow over a wide range of pH (6-9). At neutral pH and temperaturesranging from 30-35oC, S. oneidensis MR-1 reduced 100 mu M Cr(VI) toCr(III) within 20 minutes in the exponential growth phase, and the growthrate was not affected by the addition of chromate; it reduced chromateeven faster at temperatures between 35 and 39oC. At low temperatures(<25oC), acidic (pH<6.5), or alkaline (pH>8.5) conditions, 100mu M Cr(VI) strongly inhibited growth and chromate reduction. Themini-bioreactor system enabled the rapid determination of theseparameters reproducibly and easily by performing very few experiments.Besides its use for examining parameters of interest to environmentalremediation, the device will also allow one to quickly assess parametersfor optimal production of recombinant proteins or secondarymetabolites

  15. LABORATORY STUDY FOR THE REDUCTION OF CHROME (VI) TO CHROME (III) USING SODIUM METABISULFITE UNDER ACIDIC CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAM JB; GUTHRIE MD; LUECK KJ; AVILA M

    2007-07-18

    This report describes the results from RPP-PLAN-32738, 'Test Plan for the Effluent Treatment Facility to Reduce Chrome(VI) to Chrome(I1I) in the Secondary Waste Stream', using sodium metabisulfite. Appendix A presents the report as submitted by the Center for Laboratory Sciences (CLS) to CH2M HILL Hanford Group, Inc. The CLS carried out the laboratory effort under Contract Number 21065, release Number 30. This report extracts the more pertinent aspects of the laboratory effort.

  16. Genetics Home Reference: collagen VI-related myopathy

    Science.gov (United States)

    ... Twitter Home Health Conditions Collagen VI-related myopathy Collagen VI-related myopathy Printable PDF Open All Close ... Javascript to view the expand/collapse boxes. Description Collagen VI-related myopathy is a group of disorders ...

  17. Geometry VI

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 8. Geometry VI - Space-the Final Frontier. Kapil H Paranjape. Series Article Volume 1 Issue 8 August 1996 pp 28-33. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/08/0028-0033 ...

  18. VI KA’

    DEFF Research Database (Denmark)

    Sprogøe, Jonas

    2012-01-01

    Artiklen handler om hvordan man kan bruge et spil til at udvikle og måle kompetencer. Artiklen diskuterer forskellige forståelser kompetencebegrebet og diskuterer hvordan Vi Ka'-spillet bidrager til at indfange den mere aktive forståelse af kompetence, som noget du gør i en bestemt kontekst....

  19. Steps Towards Industrialization of Cu–III–VI2Thin‐Film Solar Cells:Linking Materials/Device Designs to Process Design For Non‐stoichiometric Photovoltaic Materials

    Science.gov (United States)

    Chang, Hsueh‐Hsin; Sharma, Poonam; Letha, Arya Jagadhamma; Shao, Lexi; Zhang, Yafei; Tseng, Bae‐Heng

    2016-01-01

    The concept of in‐line sputtering and selenization become industrial standard for Cu–III–VI2 solar cell fabrication, but still it's very difficult to control and predict the optical and electrical parameters, which are closely related to the chemical composition distribution of the thin film. The present review article addresses onto the material design, device design and process design using parameters closely related to the chemical compositions. Its variation leads to change in the Poisson equation, current equation, and continuity equation governing the device design. To make the device design much realistic and meaningful, we need to build a model that relates the opto‐electrical properties to the chemical composition. The material parameters as well as device structural parameters are loaded into the process simulation to give a complete set of process control parameters. The neutral defect concentrations of non‐stoichiometric CuMSe2 (M = In and Ga) have been calculated under the specific atomic chemical potential conditions using this methodology. The optical and electrical properties have also been investigated for the development of a full‐function analytical solar cell simulator. The future prospects regarding the development of copper–indium–gallium–selenide thin film solar cells have also been discussed. PMID:27840790

  20. The reactivity of Fe(II) associated with goethite formed during short redox cycles toward Cr(VI) reduction under oxic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tomaszewski, Elizabeth J.; Lee, Seungyeol; Rudolph, Jared; Xu, Huifang; Ginder-Vogel, Matthew (UW)

    2017-08-01

    Chromium (Cr) is a toxic metal that causes a myriad of health problems and enters the environment as a result of anthropogenic activities and/or natural processes. The toxicity and solubility of chromium is linked to its oxidation state; Cr(III) is poorly soluble and relatively nontoxic, while Cr(VI) is soluble and a known carcinogen. Solid Fe(II) in iron-bearing minerals, such as pyrite, magnetite, and green rusts, reduce the oxidation state of chromium, reducing its toxicity and mobility. However, these minerals are not the only potential sources of solid-associated Fe(II) available for Cr(VI) reduction. For example, ferric (Fe(III)) (hydr)oxides, such as goethite or hematite, can have Fe(II) in the solid without phase transformation; however, the reactivity of Fe(II) within Fe(III) (hydr)oxides with contaminants, has not been previously investigated. Here, we cyclically react goethite with dissolved Fe(II) followed by dissolved O2, leading to the formation of reactive Fe(II) associated with goethite. In separate reactors, the reactivity of this Fe(II) is probed under oxic conditions, by exposure to chromate (CrO42 -) after either one, two, three or four redox cycles. Cr is not present during redox cycling; rather, it is introduced to a subset of the solid after each oxidation half-cycle. Analysis of X-ray absorption near edge structure (XANES) spectra reveals that the extent of Cr(VI) reduction to Cr(III) depends not only on solid Fe(II) content but also surface area and mean size of ordered crystalline domains, determined by BET surface area analysis and X-ray diffraction (XRD), respectively. Shell-by-shell fitting of the extended X-ray absorption fine structure (EXAFS) spectra demonstrates chromium forms both single and double corner sharing complexes on the surface of goethite, in addition to sorbed Cr(III) species. Finally, transmission electron microscope (TEM) imaging and X-ray energy-dispersive spectroscopy (EDS) illustrate that Cr preferentially

  1. Effects of microbial activity and electron shuttles on the reduction of U(VI) under Fe(III)- and sulfate-reducing conditions

    Science.gov (United States)

    O'Loughlin, E. J.; Boyanov, M.; Kwon, M.; Long, P. E.; Williams, K. H.; Kemner, K. M.

    2009-12-01

    Recent studies suggest that electron shuttles such as low molecular mass quinones and humic substances may play a role in many redox reactions involved in contaminant transformations and the biogeochemical cycling of redox active elements in aquatic and terrestrial environments. In an effort to better define the role(s) of electron shuttles in biogeochemical processes in natural and engineered subsurface environments, we are investigating the effects of 9,10-anthraquinone-2,6-disulfonate (AQDS), a synthetic electron shuttle often used as a surrogate for quinone moieties in humic substances, on transformations of Fe, S, and U under conditions favorable for dissimilatory iron and sulfate reduction. Experiments were conducted in serum bottles containing a defined mineral medium amended with 30 mM Fe(III), 5 mM sulfate, and 10 mM acetate. Duplicate bottles with and without 100 μM AQDS were prepared. Fe(III) was provided as natural sienna, an iron-rich earth consisting primarily of quartz and goethite. The serum bottles were sparged with Ar and inoculated with sediment from the Rifle, CO Integrated Field Research Challenge (IFRC) site and monitored over time for Fe(II) production and sulfate and acetate consumption. After the system reached steady state with respect to Fe(III) and sulfate reduction, aliquots of suspension were collected from each system (i.e., with and without AQDS) for U(VI) reduction experiments. One set from each system was pasteurized at 70 °C for 1 hr; the other set was not pasteurized. The suspensions were spiked with 500 μM U(VI). After 48 h, 100% of the added U was removed from solution in the non-pasteurized AQDS system. However, only 58%, 25%, and 11% of added U was removed in the no AQDS non-pasteurized, AQDS pasteurized, and no AQDS pasteurized systems, respectively. U XANES analysis of the solids in each of these suspensions indicated that, with the exception of the pasteurized system without AQDS, the majority (85-95%) of the U

  2. Designing cellular manufacturing system under risk conditions ...

    African Journals Online (AJOL)

    Thus we propose a mixed integer programming approach to decision making and incorporate subcontracting risk . To control the risk of sub-contracting (cost) , the two popular percentile measures of risk are applied: value-at-risk and conditional value-at-risk. This model is capable of optimizing production cost of parts and ...

  3. Learning to Design Together: Introducing Conditional Design as a Method for Co-design Activities

    DEFF Research Database (Denmark)

    Akoglu, Canan

    2017-01-01

    contribution from each student and an active learning space was provided to the students. Based on the feedbacks, it is possible to foresee that the workshops were positive experiences especially in terms of understanding the importance of collective creativity and beyond the educational purposes...... professional practices. Based on this argument, this paper aims to propose conditional design as a method for co-design activities in design education by promoting the design process as a dynamic system which needs to be designed in itself. For this purpose, two workshops were conducted in Istanbul...

  4. The effect of Si and Al concentrations on the removal of U(VI) in the alkaline conditions created by NH3 gas

    Energy Technology Data Exchange (ETDEWEB)

    Katsenovich, Yelena P.; Cardona, Claudia; Lapierre, Robert; Szecsody, Jim; Lagos, Leonel E.

    2016-10-01

    Remediation of uranium in the deep unsaturated zone is a challenging task, especially in the presence of oxygenated, high-carbonate alkalinity soil and pore water composition typical for arid and semi-arid environments of the western regions of the U.S. This study evaluates the effect of various pore water constituencies on changes of uranium concentrations in alkaline conditions, created in the presence of reactive gases such as NH3 to effectively mitigate uranium contamination in the vadose zone sediments. This contaminant is a potential source for groundwater pollution through slow infiltration of soluble and highly mobile uranium species towards the water table. The objective of this research was to evaluate uranium sequestration efficiencies in the alkaline synthetic pore water solutions prepared in a broad range of Si, Al, and bicarbonate concentrations typically present in field systems of the western U.S. regions and identify solid uranium-bearing phases that result from ammonia gas treatment. In previous studies (Szecsody et al. 2012; Zhong et al. 2015), although uranium mobility was greatly decreased, solid phases could not be identified at the low uranium concentrations in field-contaminated sediments. The chemical composition of the synthetic pore water used in the experiments varied for silica (5–250 mM), Al3+ (2.8 or 5 mM), HCO3- (0–100 mM) and U(VI) (0.0021–0.0084 mM) in the solution mixture. Experiment results suggested that solutions with Si concentrations higher than 50 mM exhibited greater removal efficiencies of U(VI). Solutions with higher concentrations of bicarbonate also exhibited greater removal efficiencies for Si, Al, and U(VI). Overall, the silica polymerization reaction leading to the formation of Si gel correlated with the removal of U(VI), Si, and Al from the solution. If no Si polymerization was observed, there was no U removal from the supernatant solution. Speciation modeling indicated that the dominant uranium species in the

  5. Mucopolysaccharidosis VI

    Science.gov (United States)

    2010-01-01

    Mucopolysaccharidosis VI (MPS VI) is a lysosomal storage disease with progressive multisystem involvement, associated with a deficiency of arylsulfatase B leading to the accumulation of dermatan sulfate. Birth prevalence is between 1 in 43,261 and 1 in 1,505,160 live births. The disorder shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic skeletal dysplasia includes short stature, dysostosis multiplex and degenerative joint disease. Rapidly progressing forms may have onset from birth, elevated urinary glycosaminoglycans (generally >100 μg/mg creatinine), severe dysostosis multiplex, short stature, and death before the 2nd or 3rd decades. A more slowly progressing form has been described as having later onset, mildly elevated glycosaminoglycans (generally sialidosis and mucolipidosis. Before enzyme replacement therapy (ERT) with galsulfase (Naglazyme®), clinical management was limited to supportive care and hematopoietic stem cell transplantation. Galsulfase is now widely available and is a specific therapy providing improved endurance with an acceptable safety profile. Prognosis is variable depending on the age of onset, rate of disease progression, age at initiation of ERT and on the quality of the medical care provided. PMID:20385007

  6. Mucopolysaccharidosis VI

    Directory of Open Access Journals (Sweden)

    Harmatz Paul

    2010-04-01

    Full Text Available Abstract Mucopolysaccharidosis VI (MPS VI is a lysosomal storage disease with progressive multisystem involvement, associated with a deficiency of arylsulfatase B leading to the accumulation of dermatan sulfate. Birth prevalence is between 1 in 43,261 and 1 in 1,505,160 live births. The disorder shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic skeletal dysplasia includes short stature, dysostosis multiplex and degenerative joint disease. Rapidly progressing forms may have onset from birth, elevated urinary glycosaminoglycans (generally >100 μg/mg creatinine, severe dysostosis multiplex, short stature, and death before the 2nd or 3rd decades. A more slowly progressing form has been described as having later onset, mildly elevated glycosaminoglycans (generally ARSB gene, located in chromosome 5 (5q13-5q14. Over 130 ARSB mutations have been reported, causing absent or reduced arylsulfatase B (N-acetylgalactosamine 4-sulfatase activity and interrupted dermatan sulfate and chondroitin sulfate degradation. Diagnosis generally requires evidence of clinical phenotype, arylsulfatase B enzyme activity ®, clinical management was limited to supportive care and hematopoietic stem cell transplantation. Galsulfase is now widely available and is a specific therapy providing improved endurance with an acceptable safety profile. Prognosis is variable depending on the age of onset, rate of disease progression, age at initiation of ERT and on the quality of the medical care provided.

  7. 38 CFR 8.27 - Conditional designation of beneficiary.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Conditional designation of beneficiary. 8.27 Section 8.27 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS NATIONAL SERVICE LIFE INSURANCE Settlement of Insurance Maturing on Or After August 1, 1946 § 8.27 Conditional designation of beneficiary. If the...

  8. Formaldehyde removal from wastewater and air by using UV, ferrate(VI) and UV/ferrate(VI).

    Science.gov (United States)

    Talaiekhozani, Amirreza; Salari, Malihe; Talaei, Mohammad Reza; Bagheri, Marzieh; Eskandari, Zeynab

    2016-12-15

    Formaldehyde removal from an air stream absorbed into a water stream in a packed bed continuously and then removed by employing a combination of UV and ferrate(VI) as a highly-powerful oxidant in a continuous stirred tank. In addition, the removal of formaldehyde from water was investigated in both batch and continuous modes. The results of the study performed on formaldehyde-contaminated water treatment can be used for both air and water treatment process design. The primary objective of this study is to compare the performance of using UV and ferrate(VI) individually with that of using UV/ferrate(VI) simultaneously to remove formaldehyde from both air and water. Moreover, the effects of several factors such as pH, ferrate(VI) concentration and temperature on formaldehyde removal from water using ferrate(VI) method were evaluated. The results of the current study in batch condition showed that the best initial pH and ferrate(VI) concentration to obtain the highest formaldehyde removal are 2 and 1 mg/l, respectively. The results of this part of research also reveal that temperatures rise from 25 °C to 50 °C increases formaldehyde removal from 69% to 97%; however, further increase in temperature has an adverse effect on removal efficiency. The combination of UV and ferrate(VI) enhances formaldehyde removal efficiency to very close to 100% within 35 min. In continuous air stream treatment, maximum formaldehyde removal of 94% was obtained by using a packed bed scrubber with gas over liquid flow rates ratio of 1.28 m(3)/m(3). Although the results of this study shows that ferrate(VI) method for removal of formaldehyde can be considered as a promising alternative for both water and air treatment, further economic studies are required for this process to be commercialized. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Optimal design of multi-conditions for axial flow pump

    Science.gov (United States)

    Shi, L. J.; Tang, F. P.; Liu, C.; Xie, R. S.; Zhang, W. P.

    2016-11-01

    Passage components of the pump device will have a negative flow state when axial pump run off the design condition. Combined with model tests of axial flow pump, this paper use numerical simulation and numerical optimization techniques, and change geometric design parameters of the impeller to optimal design of multi conditions for Axial Flow Pump, in order to improve the efficiency of non-design conditions, broad the high efficient district and reduce operating cost. The results show that, efficiency curve of optimized significantly wider than the initial one without optimization. The efficiency of low flow working point increased by about 2.6%, the designed working point increased by about 0.5%, and the high flow working point increased the most, about 7.4%. The change range of head is small, so all working point can meet the operational requirements. That will greatly reduce operating costs and shorten the period of optimal design. This paper adopted the CFD simulation as the subject analysis, combined with experiment study, instead of artificial way of optimization design with experience, which proves the reliability and efficiency of the optimization design of multi-operation conditions of axial-flow pump device.

  10. Groundwater detection monitoring system design under conditions of uncertainty

    NARCIS (Netherlands)

    Yenigül, N.B.

    2006-01-01

    Landfills represent a wide-spread and significant threat to groundwater quality. In this thesis a methodology was developed for the design of optimal groundwater moni-toring system design at landfill sites under conditions of uncertainty. First a decision analysis approach was presented for optimal

  11. Boundary Conditions for a New Type of Design Task

    DEFF Research Database (Denmark)

    McAloone, Tim C.

    2011-01-01

    -teresting to understand the shifting focus and identification of boundary conditions that manufacturing organisations must undergo, in order to develop just as systematic an approach to the service-related aspects of their business development, as they have in place for their product development. This chapter...... and knowledge associated with the use of the product is increasingly perceived to be the new design object. But how to organise the design of combined products and services, over expanded time domains and new stakeholder boundaries? The design research community is paying increasing attention to this new design...

  12. Cranial mononeuropathy VI

    Science.gov (United States)

    ... Abducens palsy; Lateral rectus palsy; VIth nerve palsy; Cranial nerve VI palsy; Sixth nerve palsy; Neuropathy - sixth nerve ... Cranial mononeuropathy VI is damage to the sixth cranial nerve. This nerve is also called the abducens nerve. ...

  13. Dissimilatory Reduction of Cr(VI), Fe(III), and U(VI) by Cellulomonas Isolates

    Energy Technology Data Exchange (ETDEWEB)

    Smith, William Aaron; Apel, William Arnold; Peyton, B. M.; Petersen, J. N.; Sani, R.

    2002-10-01

    The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain (Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI).

  14. Dissimilatory reduction of Cr(VI), Fe(III), and U(VI) by Cellulomonas isolates.

    Science.gov (United States)

    Sani, R K; Peyton, B M; Smith, W A; Apel, W A; Petersen, J N

    2002-10-01

    The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain ( Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI).

  15. DESIGN a solar hybrid air conditioning compressor system

    Directory of Open Access Journals (Sweden)

    Khalaji Assadi M.

    2016-01-01

    Full Text Available To develop and integrate solar hybrid system into conventional air conditioning system which provides the same cooling load with considerably less electricity demand. Solar evacuated tube and DC compressor are used for compressing the refrigerant in an air conditioning system, thus effectively reducing the air conditioning electricity consumption by up to 45%. For the flow through type selected geometry of the designed evacuated U-tube collector, a three dimensional simulation and analysis of the thermal performance was done, using the solar ray-tracing model provided by the ANSYS-FLUENT software.

  16. Wave Run-up on Slender Piles in Design Conditions

    DEFF Research Database (Denmark)

    Andersen, Thomas Lykke; Frigaard, Peter; Damsgaard, M. L.

    2011-01-01

    in the design of Horns Reef 1. As a consequence damage was observed on the platforms. This has been the situation for several sites and design tools for platform loads are lacking. As a consequence a physical model test study was initiated at Aalborg University to clarify wave run-up on cylindrical piles...... to the pile an empirical factor is included on the velocity head. The evaluation of the calculation model shows that an accurate design rule can be established even in breaking wave conditions. However, calibration of a load model showed that it was necessary to increase the run-up factor on the velocity head...

  17. Design of energy efficient ventilation and air-conditioning systems

    CERN Document Server

    Seppänen, Olli; Bertilsson, Thore; Maripuu, Mari-Liis; Lamy, Hervé; Vanden Borre, Alex

    2012-01-01

    This guidebook covers numerous system components of ventilation and air-conditioning systems and shows how they can be improved by applying the latest technology products. Special attention is paid to details, which are often overlooked in the daily design practice, resulting in poor performance of high quality products once they are installed in the building system.

  18. Design of Multijunction Photovoltaic Cells Optimized for Varied Atmospheric Conditions

    Directory of Open Access Journals (Sweden)

    C. Zhang

    2014-01-01

    Full Text Available Band gap engineering provides an opportunity to not only provide higher overall conversion efficiencies of the reference AM1.5 spectra but also customize PV device design for specific geographic locations and microenvironments based on atmospheric conditions characteristic to that particular location. Indium gallium nitride and other PV materials offer the opportunity for limited bandgap engineering to match spectra. The effects of atmospheric conditions such as aerosols, cloud cover, water vapor, and air mass have been shown to cause variations in spectral radiance that alters PV system performance due to both overrating and underrating. Designing PV devices optimized for spectral radiance of a particular region can result in improved PV system performance. This paper presents a new method for designing geographically optimized PV cells with using a numerical model for bandgap optimization. The geographic microclimate spectrally resolved solar flux for twelve representative atmospheric conditions for the incident radiation angle (zenith angle of 48.1° and fixed array angle of 40° is used to iteratively optimize the band gap for tandem, triple, and quad-layer of InGaN-based multijunction cells. The results of this method are illustrated for the case study of solar farms in the New York region and discussed.

  19. Multifunctional design of footwear for hot environment condition

    Science.gov (United States)

    Dragcevic, Z.; Vujasinovic, E.; Hursa Sajatovic, A.

    2017-10-01

    For some time design of a new product is not connected only with aesthetic, artistic appearance but moreover with functionality and engineering (from rightful selection of materials, construction, and technological concept to prototyping). One good example of this is design of multifunctional footwear as well as hiking footwear, footwear for soldiers, police officers, first responders etc. All mentioned kinds of footwear have lot of specific requirements to fulfil starting from maintaining and enhancing mobility to maximizing protection and eliminating or minimizing the risk for the wearer. Therefore, designing appropriate footwear represents a great challenge not only for designers but for engineers as well. Having that entire in mind few years ago, Faculty of Textile Technology University of Zagreb started the research with the aim to develop 21st century multifunctional footwear for e.g. military, police, first respondents or any special human forces for different weather environment. The paper presents how it was done in the case of boots for hot environment conditions

  20. NOx, NH3, N2O and PN real driving emissions from a Euro VI heavy-duty vehicle. Impact of regulatory on-road test conditions on emissions.

    Science.gov (United States)

    Mendoza-Villafuerte, Pablo; Suarez-Bertoa, Ricardo; Giechaskiel, Barouch; Riccobono, Francesco; Bulgheroni, Claudia; Astorga, Covadonga; Perujo, Adolfo

    2017-12-31

    Euro VI emission standards for heavy-duty vehicles (HDVs) introduced for the first time limits for solid particle number (PN) and NH3 emissions. EU regulation also includes a Portable Emissions Measurement System (PEMS) based test at type approval, followed by in-service conformity (ISC) testing. A comprehensive study on the real-time on-road emissions of NOx, NH3, N2O and PN from a Euro VI HDV equipped with a Diesel Oxidation Catalyst (DOC), a Diesel Particle Filter (DPF), a Selective Catalytic Reduction (SCR) system and an Ammonia Oxidation Catalyst (AMOX) is presented. Our analyses revealed that up to 85% of the NOx emissions measured during the tests performed are not taken into consideration if the boundary conditions for data exclusion set in the current legislation are applied. Moreover, it was found that the highest NOx emissions were measured during urban operation. Analyses show that a large fraction urban of operation is not considered when 20% power threshold as boundary condition is applied. They also show that cold start emissions account for a large fraction of the total NOx emitted. Low emissions of PN (2.8×10(10) to 6.5×10(10)#/kWh) and NH3 (1.0 to 2.2ppm) were obtained during the on-road tests, suggesting effectiveness of the vehicle's after-treatment (DPF and AMOX). Finally, a comparison between speed-based (as currently defined by Euro VI legislation) and land-use-based (using Geographic Information System (GIS)) calculation of shares of operation was performed. Results suggest that using GIS to categorize the shares of operation could result in different interpretations depending on the criteria adopted for their definition. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Adaptation of AASHTO Pavement Design Guide for Local Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hajek, J.J. [Applied Research Associates Inc., Toronto, ON (Canada)

    2001-07-01

    The methodology used to adapt the 1993 AASHTO Guide for Design of Pavement Structures to Ontario conditions was described. The guide expresses the effect of traffic loads on pavement performance using the concept of axle Load Equivalency Factors (LEF). LEF is regarded as a pavement damage factor assigned to each specific load and axle configuration. The size of LEF is related to the damage that is expected to occur from a standard load of 80 kN carried by a single axle with dual tires. The factors are summarized to yield the number of Equivalent Single Axle Loads (ESALs) a pavement is expected to sustain during its life. A summary was also provided of the additional work done to prepare for the transition to the proposed mechanistically-based 2002 AASHTO Guide. The paper focused only on the design of flexible pavements in terms of load characterization using equivalent single axle loads along with axle load spectra, below grade and material characterization, plus initial and terminal serviceability and reliability. The AASHTO Guide uses two parameters to deal with design reliability: design reliability level and overall standard deviation. Data collected on Ontario highway pavements and materials was used for assessing the design inputs. Other data was also collected from research and development studies, laboratory experiments, and from a survey of experienced pavement design engineers. The end result was a new grouping of Ontario soils for pavement design, recommended values for the resilient modulus of below grade soils, recommendations for structural layer coefficients for Ontario pavement materials and recommendations for the initial pavement serviceability based on Ontario smoothness specifications. Results of calibration and verification processes indicate that for new flexible pavements, the AASHTO-Ontario model is in good agreement with the observed results. It was recommended that the calibration and verification of the AASHTO-Ontario model should be a

  2. Improving flight condition situational awareness through Human Centered Design.

    Science.gov (United States)

    Craig, Carol

    2012-01-01

    In aviation, there is currently a lack of accurate and timely situational information, specifically weather data, which is essential when dealing with the unpredictable complexities that can arise while flying. For example, weather conditions that require immediate evasive action by the flight crew, such as isolated heavy rain, micro bursts, and atmospheric turbulence, require that the flight crew receive near real-time and precise information about the type, position, and intensity of those conditions. Human factors issues arise in considering how to display the various sources of weather information to the users of that information and how to integrate this display into the existing environment. In designing weather information display systems, it is necessary to meet the demands of different users, which requires an examination of the way in which the users process and use weather information. Using Human Centered Design methodologies and concepts will result in a safer, more efficient and more intuitive solution. Specific goals of this approach include 1) Enabling better fuel planning; 2) Allowing better divert strategies; 3) Ensuring pilots, navigators, dispatchers and mission planners are referencing weather from the same sources; 4) Improving aircrew awareness of aviation hazards such as turbulence, icing, hail and convective activity; 5) Addressing inconsistent availability of hazard forecasts outside the United States Air Defense Identification Zone (ADIZ); and 6) Promoting goal driven approaches versus event driven (prediction).

  3. High Quality Acquisition of Surface Electromyography - Conditioning Circuit Design

    Science.gov (United States)

    Shobaki, Mohammed M.; Malik, Noreha Abdul; Khan, Sheroz; Nurashikin, Anis; Haider, Samnan; Larbani, Sofiane; Arshad, Atika; Tasnim, Rumana

    2013-12-01

    The acquisition of Surface Electromyography (SEMG) signals is used for many applications including the diagnosis of neuromuscular diseases, and prosthesis control. The diagnostic quality of the SEMG signal is highly dependent on the conditioning circuit of the SEMG acquisition system. This paper presents the design of an SEMG conditioning circuit that can guarantee to collect high quality signal with high SNR such that it is immune to environmental noise. The conditioning circuit consists of four stages; consisting of an instrumentation amplifier that is used with a gain of around 250; 4th order band pass filter in the 20-500Hz frequency range as the two initial stages. The third stage is an amplifier with adjustable gain using a variable resistance; the gain could be changed from 1000 to 50000. In the final stage the signal is translated to meet the input requirements of data acquisition device or the ADC. Acquisition of accurate signals allows it to be analyzed for extracting the required characteristic features for medical and clinical applications. According to the experimental results, the value of SNR for collected signal is 52.4 dB which is higher than the commercial system, the power spectrum density (PSD) graph is also presented and it shows that the filter has eliminated the noise below 20 Hz.

  4. SaVi: satellite constellation visualization

    OpenAIRE

    Wood, Lloyd

    2012-01-01

    SaVi, a program for visualizing satellite orbits, movement, and coverage, is maintained at the University of Surrey. This tool has been used for research in academic papers, and by industry companies designing and intending to deploy satellite constellations. It has also proven useful for demonstrating aspects of satellite constellations and their geometry, coverage and movement for educational and teaching purposes. SaVi is introduced and described briefly here.

  5. Design of a Modular Signal Conditioning Circuit for Biopotential Sensors

    Directory of Open Access Journals (Sweden)

    Winncy Y. DU

    2010-09-01

    Full Text Available Biosignal conditioning (BC is critical in biomedical instruments because it directly affects measurement accuracy, reliability, and repeatability. BC also presents a great challenge due to the small amplitude of biosignals and their ease of corruption with noise and other disturbances. This paper describes a modular BC system developed for biopotential sensors that can preserve useful information while removing unwanted noise and interference components. This BC circuit includes an instrumentation amplifier, an active 1st-order high-pass filter with Sallen-Key configuration, a 5th-order low-pass Bessel filter, and a 2nd-order Twin-T notch filter. The order of these filters and the associated components in each filter can be easily changed to adapt to different biosignals (modular feature. Data acquisition and sampling were performed using a USB6009 module with a built-in A/D converter. Testing of a real electrocardiogram on the designed signal conditioning circuit demonstrated comparable outputs to commercial devices.

  6. Co-extraction and co-stripping of U(VI) and Pu(IV) using tri-iso-amyl phosphate and tri-n-butyl phosphate in n-dodecane from nitric acid media under high loading conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sreenivasulu, Balija; Suresh, Ammath; Sivaraman, Nagarajan; Rao, P.R. Vasudeva [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Chemistry Group

    2016-08-01

    The extraction of Pu(IV) using 1.1 M solution of tri-iso-amyl phosphate (TiAP)/n-dodecane (DD) from plutonium nitrate solutions in nitric acid media was examined as a function of equilibrium aqueous phase metal ion concentration and equilibrium aqueous phase acidity at 303 K. The nitric acid concentration in the organic phase was measured as a function of equilibrium organic phase plutonium concentration. The co-extraction of U(VI) and Pu(IV) was studied using 1.1 M TiAP/DD system as a function of their equilibrium aqueous phase metal ion concentration and compared with 1.1 M tri-n-butyl phosphate (TBP)/n-DD system under identical conditions. Co-extraction and co-stripping of U(VI) and Pu(IV) were studied using 1.1 M TiAP/DD and 1.1 M TBP/DD systems in cross current mode to evaluate the number of stages required for the extraction and stripping of heavy metal ions (uranium and plutonium). The extraction and stripping efficiencies were calculated for both the systems. The saturation limit of the organic phase was also established in these studies.

  7. Vi, de civiliserede

    DEFF Research Database (Denmark)

    Nyemann, Dorthe

    2016-01-01

    Vi har i årtier troet på, at mennesker under de rette omstændigheder kan lykkes med at leve i fred og fordragelighed med hinanden. Skal vi til at erkende, at også vores samfundsstrukturer kun er en tynd fernis ovenpå et utæmmeligt voldspotentiale og egoisme?......Vi har i årtier troet på, at mennesker under de rette omstændigheder kan lykkes med at leve i fred og fordragelighed med hinanden. Skal vi til at erkende, at også vores samfundsstrukturer kun er en tynd fernis ovenpå et utæmmeligt voldspotentiale og egoisme?...

  8. Transportation and kinetic analysis of Mo(VI) ions through a MDLM system containing TNOA as carrier.

    Science.gov (United States)

    Donat, R; Durmaz, Ö; Cetişli, H

    2015-08-30

    In this report, Mo(VI) ions are transported from an aqueous donor phase into an aqueous acceptor phase by a newly designed method called as multi dropped liquid membrane (MDLM) system prepared by dissolving TNOA as carrier in kerosene. During the extraction of Mo(VI) ions by the liquid membrane system; 100ppm Mo(VI) solutions as donor phase, buffer solution(pH:9.5) and Na2CO3 in different concentrations as acceptor phase and TNOA diluted by kerosen as organic phase are used.In our experimental work, the effect of temperature by using buffer solution and Na2CO3 in the acceptor phase and effect of concentration of acceptor phase on the extraction of Mo(VI) ions were investigated. Appropriate conditions for Mo(VI) transportation were as follows: pH of donor phase is 2.00, concentration of TNOA is 0.005M, 1.00M Na2CO3 as acceptor phase, and flux rate is 50mL/min. Besides, Mo(VI) ion transportation is consecutive first order irreversible reaction and the transportation of Mo(VI) ions is diffusion controlled process. The kinetic parameters (k1, k2, Rm(max), tmax, Jd(max), Ja(max)) were calculated for the interface reactions assuming two consecutive, irreversible first-order reactions. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Aqueous Complexation Reactions Governing the Rate and Extent of Biogeochemical U(VI) Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Scott C. Brooks; Wenming Dong; Sue Carroll; James K. Fredrickson; Kenneth M. Kemner; Shelly D. Kelly

    2006-06-01

    The proposed research will elucidate the principal biogeochemical reactions that govern the concentration, chemical speciation, and reactivity of the redox-sensitive contaminant uranium. The results will provide an improved understanding and predictive capability of the mechanisms that govern the biogeochemical reduction of uranium in subsurface environments. In addition, the work plan is designed to: (1) Generate fundamental scientific understanding on the relationship between U(VI) chemical speciation and its susceptibility to biogeochemical reduction reactions. (2) Elucidate the controls on the rate and extent of contaminant reactivity. (3) Provide new insights into the aqueous and solid speciation of U(VI)/U(IV) under representative groundwater conditions.

  10. Aqueous Complexation Reactions Governing the Rate and Extent of Biogeochemical U(VI) Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Scott C. Brooks; Wenming Dong; Sue Carroll; Jim Fredrickson; Ken Kemner; Shelly Kelly

    2006-06-01

    The proposed research will elucidate the principal biogeochemical reactions that govern the concentration, chemical speciation, and reactivity of the redox-sensitive contaminant uranium. The results will provide an improved understanding and predictive capability of the mechanisms that govern the biogeochemical reduction of uranium in subsurface environments. In addition, the work plan is designed to: (1) Generate fundamental scientific understanding on the relationship between U(VI) chemical speciation and its susceptibility to biogeochemical reduction reactions. ? Elucidate the controls on the rate and extent of contaminant reactivity. (2) Provide new insights into the aqueous and solid speciation of U(VI)/U(IV) under representative groundwater conditions.

  11. Matter in Extreme Conditions Instrument - Conceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Boyce, R.F.; Boyce, R.M.; Haller, G.; Hastings, J.B.; Hays, G.; Lee, H.J.; /SLAC; Lee, R.W.; /LLNL, Livermore; Nagler, B.; /Rutherford; Scharfenstein, M.; Marsh, D.; White, W.E.; /SLAC

    2009-12-09

    The SLAC National Accelerator Laboratory (SLAC), in collaboration with Argonne National Laboratory (ANL), Lawrence Livermore National Laboratory (LLNL), and the University of California at Los Angeles (UCLA), is constructing a Free-Electron Laser (FEL) research facility. The FEL has already met its performance goals in the wavelength range 1.5 nm - 0.15 nm. This facility, the Linac Coherent Light Source (LCLS), utilizes the SLAC 2-Mile Linear Accelerator (linac) and will produce sub-picosecond pulses of short wavelength X-rays with very high peak brightness and almost complete transverse coherence. The final one-third of the SLAC linac is used as the source of electrons for the LCLS. The high energy electrons are transported across the SLAC Research Yard, into a tunnel which houses a long undulator. In passing through the undulator, the electrons are bunched by the force of their own synchrotron radiation and produce an intense, monochromatic, spatially coherent beam of X-rays. By varying the electron energy, the FEL X-ray wavelength is tunable from 1.5 nm to 0.15 nm. The LCLS includes two experimental halls as well as X-ray optics and infrastructure necessary to create a facility that can be developed for research in a variety of disciplines such as atomic physics, materials science, plasma physics and biosciences. This Conceptual Design Report, the authors believe, confirms the feasibility of designing and constructing an X-ray instrument in order to exploit the unique scientific capability of LCLS by creating extreme conditions and study the behavior of plasma under those controlled conditions. This instrument will address the Office of Science, Fusion Energy Sciences, mission objective related to study of Plasma and Warm Dense Matter as described in the report titled LCLS, the First Experiments, prepared by the LCLS Scientific Advisory Committee (SAC) in September 2000. The technical objective of the LCLS Matter in Extreme Conditions (MEC) Instrument project is

  12. An Overview on Production and Applications of Ferrate(VI

    Directory of Open Access Journals (Sweden)

    Talaiekhozani

    2016-03-01

    Full Text Available Context Coagulation, chemical oxidation and disinfection are essential processes in water and waste treatment. A chemical that can be applied for all the above mentioned purposes is ferrate(VI. Although there are many studies about ferrate(VI, no comprehensive review paper can be found about ferrate(VI from production to applications. The aim of this study was to review ferrate(VI production, measurement, stability and utilization in water and wastewater treatment. Evidence Acquisition In acidic conditions, the oxidation and reduction capacity of ferrate(VI is superior to all currently utilized oxidizers and disinfectants in water and wastewater treatment. New researches have provided the technology of using ferrate(VI for coagulation, chemical oxidation and disinfection of water and wastewater in a reactor simultaneously, which can reduce the size of water and wastewater treatment plants and increase the treatment efficiency. Results Despite the existence of these technologies, there is no full-scale application of ferrate(VI in the water and wastewater industry which it is due to difficulties associated with I, the lack of adequate researches that have demonstrated its capabilities and advantages over the existing water and wastewater treatment methods; ii, the instability of ferrate(VI depending on its method of preparation, and iii, the relatively low yield of ferrate(VI. Conclusions To solve the above mentioned difficulties, fundamental study most be carried out to discover the novel methods of ferrate(VI production, focusing on increasing the product stability and the production yield.

  13. Biosorption of chromium(VI) using immobilized Bacillius subtilis and ...

    African Journals Online (AJOL)

    Therefore, the batch removal of Cr (VI) from environment water bodies becomes necessary. Its removal from aqueous solution using immobilized Bacillus subtilis (IBBS), Pseudomonas aeruginosa (IPBS), mixed biomass (IMBS) and Alginate alone (IABS) was carried out. The conditions of influence of initial Cr (VI) ...

  14. Dual design resistor for high voltage conditioning and transmission lines

    Science.gov (United States)

    Siggins, Timothy Lynn [Newport News, VA; Murray, Charles W [Hayes, VA; Walker, Richard L [Norfolk, VA

    2007-01-23

    A dual resistor for eliminating the requirement for two different value resistors. The dual resistor includes a conditioning resistor at a high resistance value and a run resistor at a low resistance value. The run resistor can travel inside the conditioning resistor. The run resistor is capable of being advanced by a drive assembly until an electrical path is completed through the run resistor thereby shorting out the conditioning resistor and allowing the lower resistance run resistor to take over as the current carrier.

  15. and dioxouranium(vi)

    African Journals Online (AJOL)

    a

    Thorium(IV) and uranium(VI) with atomic radii of 1.65 and .... to ν(NH) vibrations. Practically no effect on these frequencies after complexation precludes the possibility of metal-coordination at this group. The absorptions at 1600 ... observation suggests involvement of unsaturated nitrogen atoms of the two azomethine groups.

  16. Designing a future Conditions Database based on LHC experience

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00064378; Formica, Andrea; Gallas, Elizabeth; Lehmann Miotto, Giovanna; Pfeiffer, A.; Govi, G.

    2015-01-01

    We describe a proposal for a new Conditions Database infrastructure that ATLAS and CMS (or other) experiments could use starting on the timescale of Run 3. This proposal is based on the experience that both experiments accumulated during Run 1. We will present the identified relevant data flows for conditions data and underline the common use cases that lead to a joint effort for the development of a new system. Conditions data are needed in any scientific experiment. It includes any ancillary data associated with primary data taking such as detector configuration, state or calibration or the environment in which the detector is operating. In any non-trivial experiment, conditions data typically reside outside the primary data store for various reasons (size, complexity or availability) and are best accessed at the point of processing or analysis (including for Monte Carlo simulations). The ability of any experiment to produce correct and timely results depends on the complete and efficient availability of ne...

  17. Designing a future Conditions Database based on LHC experience

    CERN Document Server

    Formica, Andrea; The ATLAS collaboration; Gallas, Elizabeth; Govi, Giacomo; Lehmann Miotto, Giovanna; Pfeiffer, Andreas

    2015-01-01

    The ATLAS and CMS Conditions Database infrastructures have served each of the respective experiments well through LHC Run 1, providing efficient access to a wide variety of conditions information needed in online data taking and offline processing and analysis. During the long shutdown between Run 1 and Run 2, we have taken various measures to improve our systems for Run 2. In some cases, a drastic change was not possible because of the relatively short time scale to prepare for Run 2. In this process, and in the process of comparing to the systems used by other experiments, we realized that for Run 3, we should consider more fundamental changes and possibilities. We seek changes which would streamline conditions data management, improve monitoring tools, better integrate the use of metadata, incorporate analytics to better understand conditions usage, as well as investigate fundamental changes in the storage technology, which might be more efficient while minimizing maintenance of the data as well as simplif...

  18. Operation Design of Wind Turbines in Strong Wind Conditions

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Montes, Melissa Barroso; Odgaard, Peter Fogh

    2012-01-01

    optimally. In order to reduce the possible increased loading, fatigue due to the wind gusts, control strategies have been considered for both constant sped and variable speed pitch regulated wind turbines. The control study shows that the designed controllers can reduce the standard deviations efficiently......In order to reduce the impact on the electrical grid from the shutdown of MW wind turbines at wind speeds higher than the cut-out wind speed of 25 m/s, we propose in this paper to run the turbines at high wind speeds up to 40 m/s. Two different operation designs are made for both constant speed...... and variable speed pitch regulated wind turbines. The variable speed design is more suitable for wind turbines to run at very high wind speeds which can help the turbine braking system to stop the turbine at the new "cut-out" wind speed. Reference power, rotational speed and pitch angle have been designed...

  19. Teacher collaboration in curriculum design teams : Effects, mechanisms and conditions

    NARCIS (Netherlands)

    Voogt, J.M.; Pieters, J.M.; Handelzalts, A.

    2016-01-01

    Collaborative design positively affects both professional development and the implementation of curriculum change, because teachers develop competencies and practice and develop ownership of the change. The current study was aimed to explore what empirical evidence is available about processes that

  20. Teacher collaboration in curriculum design teams : effects, mechanisms, and conditions

    NARCIS (Netherlands)

    Voogt, Joke M.; Pieters, Jules M.; Handelzalts, Adam

    2016-01-01

    Collaborative design positively affects both professional development and the implementation of curriculum change, because teachers develop competencies and practice and develop ownership of the change. The current study was aimed to explore what empirical evidence is available about processes that

  1. Avaliação do perfil de trabalhadores e das condições de trabalho em marcenarias no município de Viçosa-MG Evalution of workers' profile and work conditions joineries in Viçosa, Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Kátia Regina Silva

    2002-11-01

    Full Text Available Esta pesquisa foi desenvolvida nos ambientes de trabalho de marcenarias localizadas no município de Viçosa, Minas Gerais, para realizar o levantamento do perfil dos trabalhadores e das condições de trabalho relacionadas às atividades exercidas em marcenarias, visando a melhoria da saúde, do bem-estar, da segurança, do conforto e da produtividade dos trabalhadores. O levantamento do perfil dos trabalhadores e das condições de trabalho foi realizado por intermédio da aplicação de questionários aos trabalhadores das marcenarias avaliadas e das observações e anotações realizadas durante a coleta dos dados. Pelos resultados obtidos, foram constatados diversos problemas relacionados aos marceneiros, como, por exemplo, cansaço, dores nas pernas e na coluna, alergia devido à utilização de produtos químicos e ao pó da madeira, falta de treinamento para exercer a profissão e praticamente nenhuma noção sobre segurança e higiene no trabalho. A incidência de acidentes relatados foi baixa; as mãos foram as partes mais afetadas por cortes leves, não tendo sido relatado nenhum tipo de acidente grave. Pôde-se constatar também que há necessidade de conscientizar os proprietários das marcenarias sobre a importância e os benefícios da segurança e higiene no trabalho para os seus funcionários.This work was carried out in joineries located in Viçosa, Minas Gerais, Brazil, to survey the profile of workers and work conditions related to the activities performed, aiming to promote health, welfare, safety, comfort and productivity of the workers. This survey was carried out by means of the application of questionnaires to the workers and from observations made during data collection. According to the obtained results, various problems related to the joiners were observed, such as fatigue, pain in legs and spine, allergies due to the use of chemicals and sawdust, lack of training for the work and almost none knowledge about work

  2. II-VI semiconductor compounds

    CERN Document Server

    1993-01-01

    For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.

  3. The Design of Research Laboratories. Part I: A General Assessment. Part II: Air Conditioning and Conditioned Rooms.

    Science.gov (United States)

    Legget, R. F.; Hutcheon, N. B.

    Design factors in the planning of research laboratories are described which include--(1) location, (2) future expansion, (3) internal flexibility, (4) provision of services, (5) laboratory furnishing, (6) internal traffic, (7) space requirements, and (8) building costs. A second part discusses air-conditioning and conditioned rooms--(1)…

  4. Operation Design of Wind Turbines in Strong Wind Conditions

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Montes, Melissa Barroso; Odgaard, Peter Fogh

    2012-01-01

    In order to reduce the impact on the electrical grid from the shutdown of MW wind turbines at wind speeds higher than the cut-out wind speed of 25 m/s, we propose in this paper to run the turbines at high wind speeds up to 40 m/s. Two different operation designs are made for both constant speed...

  5. On the performance of a high head Francis turbine at design and off-design conditions

    Science.gov (United States)

    Aakti, B.; Amstutz, O.; Casartelli, E.; Romanelli, G.; Mangani, L.

    2015-01-01

    In the present paper, fully 360 degrees transient and steady-state simulations of a Francis turbine were performed at three operating conditions, namely at part load (PL), best efficiency point (BEP), and high load (HL), using different numerical approaches for the pressure-velocity coupling. The simulation domain includes the spiral casing with stay and guide vanes, the runner and the draft tube. The main target of the investigations is the numerical prediction of the overall performance of the high head Francis turbine model as well as local and integral quantities of the complete machine in different operating conditions. All results were compared with experimental data published by the workshop organization. All CFD simulations were performed at model scale with a new in-house, 3D, unstructured, object-oriented finite volume code within the framework of the open source OpenFOAM library. The novel fully coupled pressure-based solver is designed to solve the incompressible RANS- Equations and is capable of handling multiple references of frame (MRF). The obtained results show that the overall performance is well captured by the simulations. Regarding the local flow distributions within the inlet section of the draft-tube, the axial velocity is better estimated than the circumferential component.

  6. Removal of toxic Cr(VI) ions from tannery industrial wastewater using a newly designed three-phase three-dimensional electrode reactor

    Science.gov (United States)

    Grace Pavithra, K.; Senthil Kumar, P.; Carolin Christopher, Femina; Saravanan, A.

    2017-11-01

    In this research, the wastewater samples were collected from leather tanning industry at different time intervals. The parameters like pH, electrical conductivity, temperature, turbidity, chromium and chemical oxygen demand (COD) of the samples were analyzed. A three-phase three-dimensional fluidized type electrode reactor (FTER) was newly designed for the effective removal of toxic pollutants from wastewater. The influencing parameters were optimized for the maximum removal of toxic pollutants from wastewater. The optimum condition for the present system was calculated as: contact time of 30 min, applied voltage of 3 V and the particle electrodes of 15 g. The particle electrode was characterized by using FT-IR analysis. Langmuir-Hinshelwood and pseudo-second order kinetic models were fits well with the experimental data. The results showed that the FTER can be successfully employed for the treatment of industrial wastewater.

  7. Rationale and study design of ViPS - variable pressure support for weaning from mechanical ventilation: study protocol for an international multicenter randomized controlled open trial.

    Science.gov (United States)

    Kiss, Thomas; Güldner, Andreas; Bluth, Thomas; Uhlig, Christopher; Spieth, Peter Markus; Markstaller, Klaus; Ullrich, Roman; Jaber, Samir; Santos, Jose Alberto; Mancebo, Jordi; Camporota, Luigi; Beale, Richard; Schettino, Guilherme; Saddy, Felipe; Vallverdú, Immaculada; Wiedemann, Bärbel; Koch, Thea; Schultz, Marcus Josephus; Pelosi, Paolo; de Abreu, Marcelo Gama

    2013-10-31

    In pressure support ventilation (PSV), a non-variable level of pressure support is delivered by the ventilator when triggered by the patient. In contrast, variable PSV delivers a level of pressure support that varies in a random fashion, introducing more physiological variability to the respiratory pattern. Experimental studies show that variable PSV improves gas exchange, reduces lung inflammation and the mean pressure support, compared to non-variable PSV. Thus, it can theoretically shorten weaning from the mechanical ventilator. The ViPS (variable pressure support) trial is an international investigator-initiated multicenter randomized controlled open trial comparing variable vs. non-variable PSV. Adult patients on controlled mechanical ventilation for more than 24 hours who are ready to be weaned are eligible for the study. The randomization sequence is blocked per center and performed using a web-based platform. Patients are randomly assigned to one of the two groups: variable PSV or non-variable PSV. In non-variable PSV, breath-by-breath pressure support is kept constant and targeted to achieve a tidal volume of 6 to 8 ml/kg. In variable PSV, the mean pressure support level over a specific time period is targeted at the same mean tidal volume as non-variable PSV, but individual levels vary randomly breath-by-breath. The primary endpoint of the trial is the time to successful weaning, defined as the time from randomization to successful extubation. ViPS is the first randomized controlled trial investigating whether variable, compared to non-variable PSV, shortens the duration of weaning from mechanical ventilation in a mixed population of critically ill patients. This trial aims to determine the role of variable PSV in the intensive care unit. clinicaltrials.gov NCT01769053.

  8. Design of a Modular Signal Conditioning Circuit for Biopotential Sensors

    OpenAIRE

    Winncy Y. DU; Winston JOSE; Jake ASKELAND

    2010-01-01

    Biosignal conditioning (BC) is critical in biomedical instruments because it directly affects measurement accuracy, reliability, and repeatability. BC also presents a great challenge due to the small amplitude of biosignals and their ease of corruption with noise and other disturbances. This paper describes a modular BC system developed for biopotential sensors that can preserve useful information while removing unwanted noise and interference components. This BC circuit includes an instrumen...

  9. Application of Avatars in Display Design to Support Spatial Awareness under Varying Workload Conditions

    Science.gov (United States)

    2006-09-01

    AVATARS IN DISPLAY DESIGN TO SUPPORT SPATIAL AWARENESS UNDER VARYING WORKLOAD CONDITIONS by Dimitrios Myttas September 2006 Thesis Advisor...Avatars in Display Design to Support Spatial Awareness under Varying Workload Conditions 6. AUTHOR(S) Dimitrios Myttas 5. FUNDING NUMBERS 7...24 5. Human Performance – Workload Measurement ................. 24 III. PROPOSED DISPLAY DESIGN ................................................................... 27

  10. VI Nukitsa konkurss

    Index Scriptorium Estoniae

    2002-01-01

    VI Nukitsa konkursi auhinnad: Kirjanikud: I - Henno Käo ("Kusagil mujal"); II - Aidi Vallik ("Kuidas elad, Ann?"); III - Artur Jurin ("Piletijaht: uued segadused Kilulibeda teel"). Kunstnikud: I - Karel Korp (Leelo Tungla ja Karel Korbi "Tema amet"); II - Edgar Valter ("Kuidas õppida vaatama?"); III - Artur Jurin - ("Piletijaht: uued segadused Kilulibeda teel"). Täiskasvanute küsitluse võitis nii teksti kui piltidega Ene-Maris Tali ja Tarmo Tali "Tähtraamat. Aastaring Maarjamaal"

  11. New design of dynamic orthoses for neurological conditions.

    Science.gov (United States)

    Hoffman, Henry B; Blakey, Glyn L

    2011-01-01

    Repetitive task-specific training appears to improve upper extremity function among individuals with neurological injuries. However, treatment options are limited for neurological patients who cannot effectively incorporate their hand consistently for functional grasp and release/prehension activities. Traditional therapy approaches are not considered to be effective in controlled clinical trials. However, constraint induced movement therapy (CIMT) has shown to be a successful treatment approach for patients who exhibit some wrist and finger extension. The vast majority of stroke survivors, head injury and incomplete spinal cord Injury patients do not exhibit sufficient wrist and/or finger extension to qualify for CIMT. Patients with moderate to severe upper extremity hemiparesis are therefore unable to benefit from the latest advances in neuro-rehabilitation. The SaeboFlex and SaeboReach Functional Dynamic Orthoses have the biomechanical advantage in allowing prehension/grasp and release activities for individuals with moderate to severe hemiparesis. These orthoses are designed to position the neurological wrist and fingers into extension for proper functional training. This article describes Saebo's functional dynamic orthoses--the SaeboFlex, SaeboReach, and the SaeboStretch dynamic resting hand splint for contracture prevention--and summarizes developing evidence for the orthoses in the clinic/rehabilitation environment. This is a review article.

  12. Electrode Induced Removal and Recovery of Uranium (VI) from Acidic Subsurfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gregory, Kelvin [Carnegie Mellon University

    2013-08-12

    The overarching objective of this research is to provide an improved understanding of how aqueous geochemical conditions impact the removal of U and Tc from groundwater and how engineering design may be utilized to optimize removal of these radionuclides. Experiments were designed to address the unique conditions in Area 3 of ORNL while also providing broader insight into the geochemical effectors of the removal rates and extent for U and Tc. The specific tasks of this work were to: 1) quantify the impact of common aqueous geochemical and operational conditions on the rate and extent of U removal and recovery from water, 2) investigate the removal of Tc with polarized graphite electrode, and determine the influence of geochemical and operational conditions on Tc removal and recovery, 3) determine whether U and Tc may be treated simultaneous from Area 3 groundwater, and examine the bench-scale performance of electrode-based treatment, and 4) determine the capacity of graphite electrodes for U(VI) removal and develop a mathematical, kinetic model for the removal of U(VI) from aqueous solution. Overall the body of work suggests that an electrode-based approach for the remediation of acidic subsurface environments, such as those observed in Area 3 of ORNL may be successful for the removal for both U(VI) and Tc. Carbonaceous (graphite) electrode materials are likely to be the least costly means to maximize removal rates and efficiency by maximizing the electrode surface area.

  13. Photocatalytic reduction of Cr(VI) by char/TiO2 composite photocatalyst: optimization and modeling using the response surface methodology (RSM).

    Science.gov (United States)

    Antonopoulou, M; Chondrodimou, I; Bairamis, F; Giannakas, A; Konstantinou, I

    2017-01-01

    The photocatalytic reduction of Cr(VI) using pyrolytic char/TiO2 (PC/TiO2) composite catalyst under simulated solar irradiation was studied. Response surface methodology (RSM) and experimental design were used for modeling the removal kinetics and for the optimization of operational parameters. RSM was developed by considering a central composite design with four input variable, i.e. catalyst concentration, initial concentration of Cr(VI), pH, and % (v/v) methanol concentration for assessing individual and interactive effects. A quadratic model was established as a functional relationship between four independent variables and the removal efficiency of Cr(VI). It was found that all selected variables have significant effect on Cr(VI) removal efficiency; however, the pH, the % concentration of methanol, and their interaction exhibited the major effects. Within the studied experimental ranges, the optimum conditions for maximum Cr(VI) removal efficiency (72.1 %) after 60 min of photocatalytic treatment were: catalyst concentration 55 mg L-1, Cr(VI) concentration 20 mg L-1, pH 4, and 5 % (v/v) methanol concentration. Under optimum conditions, Cr(VI) reductive removal followed pseudo-first-order kinetics, and nearly complete removal took place within 90 min. The results revealed the feasibility and the effectiveness of PC/TiO2 as photocatalyst in reduction reactions due to their ability of e--h+ pair separation increasing the transfer of the photogenerated e- to the catalyst's surface and thus the reduction of Cr(VI).

  14. Fate and transport of uranium (VI) in weathered saprolite.

    Science.gov (United States)

    Kim, Young-Jin; Brooks, Scott C; Zhang, Fan; Parker, Jack C; Moon, Ji-Won; Roh, Yul

    2015-01-01

    Batch and column experiments were conducted to investigate sorption and transport of uranium (U) in the presence of saprolite derived from interbedded shale, limestone, and sandstone sequences. Sorption kinetics were measured at two initial concentrations (C0; 1, 10 μM) and three soil:solution ratios (Rs/w; 0.005, 0.25, 2 kg/L) at pH 4.5 (pH of the saprolite). The rate of U loss from solution (μmole/L/h) increased with increasing Rs/w. Uranium sorption exhibited a fast phase with 80% sorption in the first eight hours for all C0 and Rs/w values and a slow phase during which the reaction slowly approached (pseudo)equilibrium over the next seven days. The pH-dependency of U sorption was apparent in pH sorption edges. U(VI) sorption increased over the pH range 4-6, then decreased sharply at pH > 7.5. U(VI) sorption edges were well described by a surface complexation model using calibrated parameters and the reaction network proposed by Waite et al. (1994). Sorption isotherms measured using the same Rs/w and pH values showed a solids concentration effect where U(VI) sorption capacity and affinity decreased with increasing solids concentration. This effect may have been due to either particle aggregation or competition between U(VI) and exchangeable cations for sorption sites. The surface complexation model with calibrated parameters was able to predict the general sorption behavior relatively well, but failed to reproduce solid concentration effects, implying the importance of appropriate design if batch experiments are to be utilized for dynamic systems. Transport of U(VI) through the packed column was significantly retarded. Transport simulations were conducted using the reactive transport model HydroGeoChem (HGC) v5.0 that incorporated the surface complexation reaction network used to model the batch data. Model parameters reported by Waite et al. (1994) provided a better prediction of U transport than optimized parameters derived from our sorption edges. The

  15. Conditional Allele Mouse Planner (CAMP): software to facilitate the planning and design of breeding strategies involving mice with conditional alleles.

    Science.gov (United States)

    Hoffert, Jason D; Pisitkun, Trairak; Miller, R Lance

    2012-06-01

    Transgenic and conditional knockout mouse models play an important role in biomedical research and their use has grown exponentially in the last 5-10 years. Generating conditional knockouts often requires breeding multiple alleles onto the background of a single mouse or group of mice. Breeding these mice depends on parental genotype, litter size, transmission frequency, and the number of breeding rounds. Therefore, a well planned breeding strategy is critical for keeping costs to a minimum. However, designing a viable breeding strategy can be challenging. With so many different variables this would be an ideal task for a computer program. To facilitate this process, we created a Java-based program called Conditional Allele Mouse Planner (CAMP). CAMP is designed to provide an estimate of the number of breeders, amount of time, and costs associated with generating mice of a particular genotype. We provide a description of CAMP, how to use it, and offer it freely as an application.

  16. Vi tror, vi forstår hinanden, men det gør vi ikke

    DEFF Research Database (Denmark)

    Boysen, Mikkel Snorre Wilms

    2016-01-01

    Vores verdensbillede er baseret på en tro på, at vi forstår hinanden. Men meget tyder på, at denne tro snarere er en illusion. Derfor må vi indstille os på, at der skal en særlig indsats til, hvis vi skal kunne forstå vores omverden og menneskene i den......Vores verdensbillede er baseret på en tro på, at vi forstår hinanden. Men meget tyder på, at denne tro snarere er en illusion. Derfor må vi indstille os på, at der skal en særlig indsats til, hvis vi skal kunne forstå vores omverden og menneskene i den...

  17. Environmental survey of Region VI, Haltenbanken, 2009; Miljoeundersoekelse i Region VI, Haltenbanken, 2009

    Energy Technology Data Exchange (ETDEWEB)

    Holm, May-Helen; Cochrane, Sabine; Mannvik, Hans-Petter; Wasbotten, Ingar Halvorsen

    2010-07-01

    There has been an environmental investigation in Region VI Halten Bank. This report presents the results of the chemical and biological assays performed on samples from a total of 316 stations in 16 fields and 15 regional stations. A status of environmental conditions in the region is given at the end of the report. (AG)

  18. Environmental Survey in Region VI, Haltenbanken, 2009. Summary report; Miljoeundersoekelse i Region VI, Haltenbanken, 2009. Sammendragsrapport

    Energy Technology Data Exchange (ETDEWEB)

    Mannvik, Hans-Petter; Wasbotten, Ingar Halvorsen

    2010-07-01

    An environmental survey of Region VI, Haltenbanken, has been carried out. This report presents the results from the analyses carried out on samples from a total of 316 stations at 16 fields and 15 regional stations. A status of the environmental conditions in the region is given at the end of the report. (Author)

  19. Study on the design schemes of the air-conditioning system in a gymnasium

    Science.gov (United States)

    Zhang, Yujin; Wu, Xinwei; Zhang, Jing; Pan, Zhixin

    2017-08-01

    In view of designing the air conditioning project for a gymnasium successfully, the cooling and heating source schemes are fully studied by analyzing the surrounding environment and energy conditions of the project, as well as the analysis of the initial investment and operating costs, which indicates the air source heat pump air conditioning system is the best choice for the project. The indoor air conditioning schemes are also studied systematically and the optimization of air conditioning schemes is carried out in each area. The principle of operating conditions for the whole year is followed and the quality of indoor air and energy-saving are ensured by the optimized design schemes, which provide references for the air conditioning system design in the same kinds of building.

  20. ADSORPTION OF Cr(VI ON BLACK WATER

    Directory of Open Access Journals (Sweden)

    Rasti Januarita

    2010-06-01

    Full Text Available The effect of initial concentration of Cr(VI on adsorption to black water of Gambut, District of Banjar, South Borneo has been investigated, as well as interaction between Cr(VI species and functional black water organic fraction. The initial work was optimization of Cr(VI determination using UV-Visible Spectrophotometry with diphenylcarbacide as complexing agent and preparation of black water using mixture of 2% HCl and 5% HF with HCl-HF ratio of 1 : 1 (v/v. The quantity of Cr(VI species adsorbed on black water was calculated by determining the amount of Cr(VI species in solution before and after interaction. The functional groups in interaction between Cr(VI species and black water organic fraction was studied qualitatively using infrared spectroscopy. The results showed that optimum condition for Cr(VI species analysis using UV-Visible spectrophotometry with diphenylcarbacide as complexing agent was at wave length of 540 nm, pH 1,5, 15 - 60 minutes at which complex remain stable, and minimum mol ratio of diphenylcarbacide : Cr(VI 45 : 1, and has a sensitivity of 1.134 mg/L and detection limit of 0.00495 mg/L. The analysis was not affected by the presence of Cr(III in concentration less than 40 times of Cr(VI concentration. After treatment with HCl-HF the quantity of black water organic fraction showing humic acid properties decreased 0,1998 percent. Organic fraction of black water used adsorpted Cr(VIwith capacity of 4,050 mg/g.   Keywords: Adsorption, Cr(VI, Black Water

  1. Protostars and Planets VI

    Science.gov (United States)

    Beuther, Henrik; Klessen, Ralf S.; Dullemond, Cornelis P.; Henning, Thomas

    The Protostars and Planets book and conference series has been a long-standing tradition that commenced with the first meeting led by Tom Gehrels and held in Tucson, Arizona, in 1978. The goal then, as it still is today, was to bridge the gap between the fields of star and planet formation as well as the investigation of planetary systems and planets. As Tom Gehrels stated in the preface to the first Protostars and Planets book, "Cross-fertilization of information and understanding is bound to occur when investigators who are familiar with the stellar and interstellar phases meet with those who study the early phases of solar system formation." The central goal remained the same for the subsequent editions of the books and conferences Protostars and Planets II in 1984, Protostars and Planets III in 1990, Protostars and Planets IV in 1998, and Protostars and Planets V in 2005, but has now been greatly expanded by the flood of new discoveries in the field of exoplanet science. The original concept of the Protostars and Planets series also formed the basis for the sixth conference in the series, which took place on July 15-20, 2013. It was held for the first time outside of the United States in the bustling university town of Heidelberg, Germany. The meeting attracted 852 participants from 32 countries, and was centered around 38 review talks and more than 600 posters. The review talks were expanded to form the 38 chapters of this book, written by a total of 250 contributing authors. This Protostars and Planets volume reflects the current state-of-the-art in star and planet formation, and tightly connects the fields with each other. It is structured into four sections covering key aspects of molecular cloud and star formation, disk formation and evolution, planetary systems, and astrophysical conditions for life. All poster presentations from the conference can be found at www.ppvi.org. In the eight years that have passed since the fifth conference and book in the

  2. Investigations on photoelectrocatalytic reduction of Cr(VI) over titanium dioxide anode and metal cathode

    Energy Technology Data Exchange (ETDEWEB)

    Song, Han; Shang, Jing, E-mail: shangjing@pku.edu.cn; Ye, Junhui; Li, Qian

    2014-01-31

    Photocatalytic and photoelectrocatalytic (PEC) reductions of Cr(VI) based on TiO{sub 2} thin films were investigated under various conditions. Photogenerated electrons transferred from TiO{sub 2} thin film to cathode can contribute to PEC reduction of Cr(VI) only when the Fermi level of cathode lies above the chemical potential of Cr(VI), almost independent on the applied voltage of the direct current. In addition, the TiO{sub 2}-coated anode is the major site that accommodates the PEC reduction of Cr(VI) with hole scavenger citric acid, regardless of the Fermi level of the cathode. Although electron transfer from TiO{sub 2} to Cr(VI) is an exothermic process, the photogenerated holes in TiO{sub 2} can markedly hamper Cr(VI) reduction over the TiO{sub 2} thin film by oxidizing the lower-valence Cr back to Cr(VI), which may be counteracted by the citric acid. This research provides some in-depth insights on developing photocatalysts which enable highly efficient PEC reduction of Cr(VI) in the future. - Highlights: • Cr(VI) reduction on TiO{sub 2} photoanode is dominant with the addition of citric acid. • Cr(VI) is reduced on photocathode with Fermi level above Cr(VI) chemical potential. • Photogenerated holes can hamper Cr(VI) photoreduction over TiO{sub 2}.

  3. vi glass

    Science.gov (United States)

    Wiersma, D. S.

    2015-06-01

    Lévy glass is a new material which is obtained by assembly of scattering elements. The result is a bulk material which has different degrees of elasticity (from rigid as window glass to flexible as certain plastics) and which can be shaped into any desired form. In particular, Lévy glasses have special optical properties not present in other materials. The name Lévy glass is based on the fact that under certain conditions light waves perform a Lévy walk inside these materials and the resulting optical transport is superdiffusive. From a structural point of view a Lévy glass is a random fractal. We will review the optical and structural properties of Lévy glasses, their design criteria, as well as their experimental realization. Also we will go into various fundamental aspects of Lévy-type light transport, discussing both superdiffusion as well as interference effects like weak and strong localization.

  4. Assessing the ecological condition of streams in a southeastern Brazilian basin using a probabilistic monitoring design.

    Science.gov (United States)

    Jiménez-Valencia, Juliana; Kaufmann, Philip R; Sattamini, Ana; Mugnai, Riccardo; Baptista, Darcilio Fernandes

    2014-08-01

    Prompt assessment and management actions are required if we are to reduce the current rapid loss of habitat and biodiversity worldwide. Statistically valid quantification of the biota and habitat condition in water bodies are prerequisites for rigorous assessment of aquatic biodiversity and habitat. We assessed the ecological condition of streams in a southeastern Brazilian basin. We quantified the percentage of stream length in good, fair, and poor ecological condition according to benthic macroinvertebrate assemblage. We assessed the risk of finding degraded ecological condition associated with degraded aquatic riparian physical habitat condition, watershed condition, and water quality. We describe field sampling and implementation issues encountered in our survey and discuss design options to remedy them. Survey sample sites were selected using a spatially balanced, stratified random design, which enabled us to put confidence bounds on the ecological condition estimates derived from the stream survey. The benthic condition index indicated that 62 % of stream length in the basin was in poor ecological condition, and 13 % of stream length was in fair condition. The risk of finding degraded biological condition when the riparian vegetation and forests in upstream catchments were degraded was 2.5 and 4 times higher, compared to streams rated as good for the same stressors. We demonstrated that the GRTS statistical sampling method can be used routinely in Brazilian rain forests and other South American regions with similar conditions. This survey establishes an initial baseline for monitoring the condition and trends of streams in the region.

  5. PROBLEMS OF DESIGN AND CONSTRUCTION OF UNDERGROUND AND TRANSPORT FACILITIES IN THE CONDITIONS OF BELARUS

    Directory of Open Access Journals (Sweden)

    V. A. Sernov

    2010-03-01

    Full Text Available The experience of design and erecting of underground and transport structures, fencing deep excavations in cramped urban conditions on the examples of various projects in the Republic of Belarusis presented in the paper.

  6. Determination of the Joint Confidence Region of Optimal Operating Conditions in Robust Design by Bootstrap Technique

    OpenAIRE

    Park, Chanseok

    2012-01-01

    Robust design has been widely recognized as a leading method in reducing variability and improving quality. Most of the engineering statistics literature mainly focuses on finding "point estimates" of the optimum operating conditions for robust design. Various procedures for calculating point estimates of the optimum operating conditions are considered. Although this point estimation procedure is important for continuous quality improvement, the immediate question is "how accurate are these o...

  7. A methodology for model-based greenhouse design: Part 5, greenhouse design optimisation for southern-Spanish and Dutch conditions

    NARCIS (Netherlands)

    Vanthoor, B.H.E.; Stigter, J.D.; Henten, van E.J.; Stanghellini, C.; Visser, de P.H.B.; Hemming, S.

    2012-01-01

    An optimisation algorithm, as an essential part of a model-based method to design greenhouses for a broad range of climatic and economic conditions, was described. This algorithm – a modified controlled random search using parallel computing – maximised the annual Net Financial Return (NFR) for a

  8. Study of seismic design bases and site conditions for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    1980-04-01

    This report presents the results of an investigation of four topics pertinent to the seismic design of nuclear power plants: Design accelerations by regions of the continental United States; review and compilation of design-basis seismic levels and soil conditions for existing nuclear power plants; regional distribution of shear wave velocity of foundation materials at nuclear power plant sites; and technical review of surface-founded seismic analysis versus embedded approaches.

  9. Relaxed formulation of the design conditions for Takagi-Sugeno fuzzy virtual actuators

    Directory of Open Access Journals (Sweden)

    Filasová Anna

    2016-06-01

    Full Text Available The H∞ norm approach to virtual actuators design, intended to Takagi-Sugeno fuzzy continuous-time systems, is presented in the paper. Using the second Ljapunov method, the design conditions are formulated in terms of linear matrix inequalities in adapted bounded real lemma structures. Related to the static output controller, and for systems under influence of single actuator faults, the design steps are revealed for a three-tank system plant.

  10. ViFiLite Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ViFiLite is a wireless infrastructure that utilizes the advantages of a V-band technology in supporting data gathering for structural health monitoring as well as...

  11. Changes in the Kinetics of Uranium(VI) Sorption Reactions to Mineral Surfaces in the Presence of Fulvic Acid

    Science.gov (United States)

    Honeyman, B. D.; Tinnacher, R. M.

    2010-12-01

    the underlying mechanisms of fulvic acid effects on U(VI) sorption behavior depending on the relative concentrations of metals, organic ligands and mineral surface sites. The observed variations in metal sorption kinetics are relevant for lab-scale sorption experiments, which are often designed to determine metal sorption characteristics in the presence and absence of organic matter under equilibrium conditions. Furthermore, in dynamic flow-systems on the field scale, apparent net effects of natural organic matter on metal sorption behavior may in fact be due to a combination of (1) changes in metal sorption affinities and (2) kinetic limitations of metal surface reactions. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  12. Skal vi have flere krondyr?

    DEFF Research Database (Denmark)

    Pedersen, Jens Christian

    2008-01-01

    Vi kunne have væsentligt flere krondyr i den danske natur end vi har i øjeblikket. Den primære årsag er jagt. Det viser en ny undersøgelse fra Danmarks Miljøundersøgelser ved Aarhus Universitet. Bestanden af krondyr er ganske vist steget meget siden 1970, men der er både plads og føde til mange...

  13. Solar Pilot Plant, Phase I. Preliminary design report. Volume VI. Electrical power generation; master control subsystems; balance of plant CDRL item 2

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-05-01

    The Honeywell electrical power generation subsystem centers on a General Electric dual admission, triple extraction turbine generator sized to the output requirements of the Pilot Plant. The turbine receives steam from the receiver subsystem and/or the thermal storage subsystem and supplies those subsystems with feedwater. The turbine condensor is wet cooled. The plant control system consists of a coordinated digital master and subsystem digital/analog controls. The remainder of the plant, work spaces, maintenance areas, roads, and reception area are laid out to provide maximum convenience compatible with utility and safety. Most of the activities are housed in a complex around the base of the receiver tower. This volume contains a description of the relationship of the electrical power generation subsystem to the rest of the plant, the design methodology and evolution, the interface integration and control, and the operation and maintenance procedures.

  14. THERMAL COMFORT STUDY OF AN AIR-CONDITIONED DESIGN STUDIO IN TROPICAL SURABAYA

    Directory of Open Access Journals (Sweden)

    Agus Dwi Hariyanto

    2005-01-01

    Full Text Available This paper evaluates the current thermal comfort condition in an air-conditioned design studio using objective measurement and subjective assessment. Objective measurement is mainly to quantify the air temperature, MRT, relative humidity, and air velocity. Subjective assessment is conducted using a questionnaire to determine the occupants thermal comfort sensations and investigate their perception of the thermal comfort level. A design studio in an academic institution in Surabaya was chosen for the study. Results show that more than 80% of the occupants accepted the indoor thermal conditions even though both the environmental and comfort indices exceeded the limit of the standard (ASHRAE Standard 55 and ISO 7730. In addition, non-uniformity of spatial temperature was present in this studio. Some practical recommendations were made to improve the thermal comfort in the design studio.

  15. Adsorption of Cr(VI) onto Hybrid Membrane of Carboxymethyl Chitosan and Silicon Dioxide

    OpenAIRE

    Yanling Deng; Naoki Kano; Hiroshi Imaizumi

    2017-01-01

    In this study, a new adsorbent material was synthesized by using carboxymethyl chitosan and silicon dioxide. The hybrid membrane was used as an adsorbent for the removal of Cr(VI) from aqueous solutions. The adsorption potential of Cr(VI) by the hybrid materials was investigated by varying experimental conditions such as pH, contact time, and the dosage of the hybrid membrane. Adsorption isotherms of Cr(VI) onto the hybrid membrane were studied with varying initial concentrations under optimu...

  16. Remediation of chromium-slag leakage with electricity cogeneration via a urea-Cr(VI) cell

    OpenAIRE

    Binbin Yu; Huimin Zhang; Wei Xu; Gang Li; Zucheng Wu

    2014-01-01

    Chromium pollution has been historically widespread throughout the world. Most available remediation technologies often require energy consumption. This study is aimed to develop electrochemical remediation for Cr(VI) in chromium-slag leakage with self-generated electricity. Dynamic leaching experiments of chromium-slag samples were conducted to survey the release and leaching behavior of Cr(VI). Based on previous work, a unique urea-Cr(VI) was designed, in which urea was employed as the fuel...

  17. Bundling into the future - Structural conditions for business model design in new ICT services

    DEFF Research Database (Denmark)

    Henten, Anders; Godø, Helge

    Based on a case study of multi-play and mobile voice over IP (MVoIP) in primarily Denmark and Norway, the paper presents an analysis of the structural conditions for the design of business models regarding new information and communication services. Multi-play and MVoIP represent different kinds...... of services in terms of structural conditions market-wise and in regulatory terms. As the two service categories are relatively new on the market, dominating business model designs have not yet settled and the strategic choices of companies are still open. Being on the market, the discussion on the business...

  18. Bundling into the future - Structural conditions for business model design in new ICT services

    OpenAIRE

    Henten, Anders; Godø, Helge

    2008-01-01

    Based on a case study of multi-play and mobile voice over IP (MVoIP) in primarily Denmark and Norway, the paper presents an analysis of the structural conditions for the design of business models regarding new information and communication services. Multi-play and MVoIP represent different kinds of services in terms of structural conditions market-wise and in regulatory terms. As the two service categories are relatively new on the market, dominating business model designs have not yet settle...

  19. Computational Design of Short Pulse Laser Driven Iron Opacity Measurements at Stellar-Relevant Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madison E. [Univ. of Florida, Gainesville, FL (United States)

    2017-05-20

    Opacity is a critical parameter in the simulation of radiation transport in systems such as inertial con nement fusion capsules and stars. The resolution of current disagreements between solar models and helioseismological observations would bene t from experimental validation of theoretical opacity models. Overall, short pulse laser heated iron experiments reaching stellar-relevant conditions have been designed with consideration of minimizing tamper emission and optical depth effects while meeting plasma condition and x-ray emission goals.

  20. Surface pressure characteristics of a highly loaded turbine blade at design and off-design conditions; a CFD methodology

    Science.gov (United States)

    Vakilipour, S.; Habibnia, M.; Sabour, M. H.; Riazi, R.; Mohammadi, M.

    2017-05-01

    The flow field passing through a highly loaded low pressure (LP) turbine cascade is numerically investigated at design and off-design conditions. The Field Operation And Manipulation (OpenFOAM) platform is used as the computational Fluid Dynamics (CFD) tool. In this regard, the influences of grid resolution on the results of k- ɛ, k- ω, and large-eddy simulation (LES) turbulence models are investigated and compared with those of experimental measurements. A numerical pressure undershoot is appeared near the end of blade pressure surface which is sensitive to grid resolution and flow turbulence modeling. The LES model is able to resolve separation on both coarse and fine grid resolutions. In addition, the off-design flow condition is modeled by negative and positive inflow incidence angles. The numerical experiments show that a separation bubble generated on blade pressure side is predicted by LES. The total pressure drop has also been calculated at incidence angles between -20° and +8°. The minimum total pressure drop is obtained by k- ω and LES at design point.

  1. Characterization of Citrobacter sp. line 328 as a source of Vi for a Vi-CRM(197) glycoconjugate vaccine against Salmonella Typhi.

    Science.gov (United States)

    Rondini, Simona; Micoli, Francesca; Lanzilao, Luisa; Pisoni, Ivan; Di Cioccio, Vito; Saul, Allan J; Martin, Laura B

    2012-11-26

    Salmonella enterica serovar Typhi is the causative agent of typhoid fever with over 22 million cases and over 200,000 deaths reported annually. A vaccine is much needed for use in young children and the Novartis Vaccines Institute for Global Health (NVGH) is developing a conjugate vaccine which targets S. Typhi Vi capsular polysaccharide. Here we describe a method suitable for industrial scale production of the Vi antigen based on expression by a Citrobacter line. We optimized the production of Vi by selecting a suitable Citrobacter strain (Citrobacter 328) that yields high and stable expression of Vi in chemically defined medium under industrial-scale fermentation conditions. Vi-CRM197 made using Vi from Citrobacter 328 elicited high anti-Vi antibody levels in mice and rabbits. Citrobacter 328 is a suitable strain for production of Vi for conjugate anti-Typhi vaccines. Being a BSL-1 organism, which grows in defined medium and stably produces high yields of Vi, it offers excellent potential for safe production of inexpensive vaccines for populations at risk of typhoid fever.

  2. Design as a Condition for Prosperity in Czech Businesses - A Comparative Study

    Directory of Open Access Journals (Sweden)

    Kramolis Jan

    2015-12-01

    Full Text Available The purpose of the paper is to comprehensively review the sources of design management, business prosperity and competitiveness. The study shows the current situation in Czech businesses. Furthermore, this paper also attempts to analyze and identify the awareness of companies concerning the relation to design as a condition for business prosperity. The primary aim of the research is to investigate design as a condition of prosperity in Czech businesses. A comprehensive review of the extant literature and journals identified several sources of design approach and various definitions of business prosperity. The research consists of two main parts. Firstly, a method of smart internet questionnaires designed by the author was used. After that, the data were analyzed using mosaic plot and elementary statistics calculations, and seeking mutual dependence, followed by a comparative method. Finally, the findings were processed by comparative study that aims to compare the years 2012 and 2014. The results of the research offer interesting findings. This paper identifies several interesting aspects regarding design within Czech companies, including the mindset of management (the insight gap of Czech businesses regarding design in their business.

  3. Balanced RAP/RAS mix design and performance evaluation for project - specific service conditions.

    Science.gov (United States)

    2013-01-01

    This presentation summarizes Projects 0-6092/0-6614. It includes accomplishments, best practices, field performance data of RAP/RAS test sections, balanced RAP/RAS mix design for project-specific conditions, and approaches for improving RAP/RAS mix p...

  4. Design of the Violence and Stress Assessment (ViStA) study: a randomized controlled trial of care management for PTSD among predominantly Latino patients in safety net health centers.

    Science.gov (United States)

    Meredith, Lisa S; Eisenman, David P; Green, Bonnie L; Kaltman, Stacey; Wong, Eunice C; Han, Bing; Cassells, Andrea; Tobin, Jonathan N

    2014-07-01

    Posttraumatic stress disorder (PTSD) is a common problem in primary care. Although effective treatments are available, little is known about whether such treatments are effective within the context of Federally Qualified Health Centers (FQHCs) that serve as national "safety nets" for providing primary care for low income and underinsured patients. The Violence and Stress Assessment (ViStA) study is the first randomized controlled trial (RCT) to test the impact of a care management intervention for treating PTSD in FQHCs. To develop a PTSD management intervention appropriate for lower resource FQHCs and the predominantly Latino patients they serve, formative work was conducted through a collaborative effort between researchers and an FQHC practice-based research network. This article describes how FQHC stakeholders were convened to review, assess, and prioritize evidence-based strategies for addressing patient, clinician, and system-level barriers to care. This multi-component care management intervention incorporates diagnosis with feedback, patient education and activation; navigation and linkage to community resources; clinician education and medication guidance; and structured cross-disciplinary communication and continuity of care, all facilitated by care managers with FQHC experience. We also describe the evaluation design of this five-year RCT and the characteristics of the 404 English or Spanish speaking patients enrolled in the study and randomized to either the intervention or to usual care. Patients are assessed at baseline, six months, and 12 months to examine intervention effectiveness on PTSD, other mental health symptoms, health-related quality-of-life, health care service use; and perceived barriers to care and satisfaction with care. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Pre-Swirl Stator and Propeller Design for Varying Operating Conditions

    DEFF Research Database (Denmark)

    Saettone, Simone; Regener, Pelle Bo; Andersen, Poul

    2016-01-01

    .To investigate the propeller and stator designs and configurations in different operating conditions, the computationally inexpensive vortex-lattice method is used a sa first step to optimize the geometry in an initial parameter study. Then the flow over hull, stator and propelleris simulated in a CFD......Over the last two decades, an increasing number of studies have been conducted to develop and improve energy saving devices (ESDs) in order to increase the propulsive effciency. One well-known example is the pre-swirlstator (PSS), which consists of an often asymmetric arrangement of fixed stator...... blades ahead of the propeller.This paper describes the hydrodynamic design of apre-swirl stator with radially variable pitch, paired with aconventional propeller. The aim is to achieve the highest possible effciency in various operating conditions, and to avoid effciency penalties in off-design operation...

  6. On the Stark broadening of Cr VI spectral lines in astrophysical plasma

    Science.gov (United States)

    Dimitrijević, M. S.; Simić, Z.; Sahal-Bréchot, S.

    2017-02-01

    Stark broadening parameters for Cr VI lines have been calculated using semiclassical perturbation method for conditions of interest for stellar plasma. Here are presented, as an example of obtained results, Stark broadening parameters for electron- and proton-impact broadening for Cr VI 4s 2S-4p 2P° λ = 1430 Å and Cr VI 4p 2P°-5s 2S λ = 611.8 Å multiplets. The obtained results are used to demonstrate the importance of Stark broadening of Cr VI in DO white dwarf atmospheres. Also the obtained results will enter in STARK-B database which is included in Virtual Atomic and Molecula Data Center - VAMDC.

  7. The Design of Large Geothermally Powered Air-Conditioning Systems Using an Optimal Control Approach

    Science.gov (United States)

    Horowitz, F. G.; O'Bryan, L.

    2010-12-01

    The direct use of geothermal energy from Hot Sedimentary Aquifer (HSA) systems for large scale air-conditioning projects involves many tradeoffs. Aspects contributing towards making design decisions for such systems include: the inadequately known permeability and thermal distributions underground; the combinatorial complexity of selecting pumping and chiller systems to match the underground conditions to the air-conditioning requirements; the future price variations of the electricity market; any uncertainties in future Carbon pricing; and the applicable discount rate for evaluating the financial worth of the project. Expanding upon the previous work of Horowitz and Hornby (2007), we take an optimal control approach to the design of such systems. By building a model of the HSA system, the drilling process, the pumping process, and the chilling operations, along with a specified objective function, we can write a Hamiltonian for the system. Using the standard techniques of optimal control, we use gradients of the Hamiltonian to find the optimal design for any given set of permeabilities, thermal distributions, and the other engineering and financial parameters. By using this approach, optimal system designs could potentially evolve in response to the actual conditions encountered during drilling. Because the granularity of some current models is so coarse, we will be able to compare our optimal control approach to an exhaustive search of parameter space. We will present examples from the conditions appropriate for the Perth Basin of Western Australia, where the WA Geothermal Centre of Excellence is involved with two large air-conditioning projects using geothermal water from deep aquifers at 75 to 95 degrees C.

  8. Magnetic resonance imaging in patients with cardiac pacemakers: era of "MR Conditional" designs

    Directory of Open Access Journals (Sweden)

    Shellock Frank G

    2011-10-01

    Full Text Available Abstract Advances in cardiac device technology have led to the first generation of magnetic resonance imaging (MRI conditional devices, providing more diagnostic imaging options for patients with these devices, but also new controversies. Prior studies of pacemakers in patients undergoing MRI procedures have provided groundwork for design improvements. Factors related to magnetic field interactions and transfer of electromagnetic energy led to specific design changes. Ferromagnetic content was minimized. Reed switches were modified. Leads were redesigned to reduce induced currents/heating. Circuitry filters and shielding were implemented to impede or limit the transfer of certain unwanted electromagnetic effects. Prospective multicenter clinical trials to assess the safety and efficacy of the first generation of MR conditional cardiac pacemakers demonstrated no significant alterations in pacing parameters compared to controls. There were no reported complications through the one month visit including no arrhythmias, electrical reset, inhibition of generator output, or adverse sensations. The safe implementation of these new technologies requires an understanding of the well-defined patient and MR system conditions. Although scanning a patient with an MR conditional device following the strictly defined patient and MR system conditions appears straightforward, issues related to patients with pre-existing devices remain complex. Until MR conditional devices are the routine platform for all of these devices, there will still be challenging decisions regarding imaging patients with pre-existing devices where MRI is required to diagnose and manage a potentially life threatening or serious scenario. A range of other devices including ICDs, biventricular devices, and implantable physiologic monitors as well as guidance of medical procedures using MRI technology will require further biomedical device design changes and testing. The development and

  9. Model Based Optimal Sensor Network Design for Condition Monitoring in an IGCC Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rajeeva; Kumar, Aditya; Dai, Dan; Seenumani, Gayathri; Down, John; Lopez, Rodrigo

    2012-12-31

    This report summarizes the achievements and final results of this program. The objective of this program is to develop a general model-based sensor network design methodology and tools to address key issues in the design of an optimal sensor network configuration: the type, location and number of sensors used in a network, for online condition monitoring. In particular, the focus in this work is to develop software tools for optimal sensor placement (OSP) and use these tools to design optimal sensor network configuration for online condition monitoring of gasifier refractory wear and radiant syngas cooler (RSC) fouling. The methodology developed will be applicable to sensing system design for online condition monitoring for broad range of applications. The overall approach consists of (i) defining condition monitoring requirement in terms of OSP and mapping these requirements in mathematical terms for OSP algorithm, (ii) analyzing trade-off of alternate OSP algorithms, down selecting the most relevant ones and developing them for IGCC applications (iii) enhancing the gasifier and RSC models as required by OSP algorithms, (iv) applying the developed OSP algorithm to design the optimal sensor network required for the condition monitoring of an IGCC gasifier refractory and RSC fouling. Two key requirements for OSP for condition monitoring are desired precision for the monitoring variables (e.g. refractory wear) and reliability of the proposed sensor network in the presence of expected sensor failures. The OSP problem is naturally posed within a Kalman filtering approach as an integer programming problem where the key requirements of precision and reliability are imposed as constraints. The optimization is performed over the overall network cost. Based on extensive literature survey two formulations were identified as being relevant to OSP for condition monitoring; one based on LMI formulation and the other being standard INLP formulation. Various algorithms to solve

  10. a New Active Control Strategy for Wind-Turbine Blades Under Off-Design Conditions

    Science.gov (United States)

    Zhang, Ri-Kui; Wu, Jie-Zhi; Chen, Shi-Yi

    A new active control strategy for wind-turbine blades under off-design conditions has been investigated in this paper. According to our previous work, in comparison with the traditional straight leading-edge blade, a new kind of bionic blades with a sinusoidal leading edge can significantly enhance the turbine's power output at high speed inflows. However, the wavy leading-edge shape is unfavorable under the design operating conditions since an early boundary-layer separation is inevitable for a wind-turbine blade because of the geometric disturbances of the leading-edge tubercles. But for the present active control, the deflect in wavy leading-edge blades can be eliminated by introducing a series of small flat delta wings as the control units, since delta wings can also generate powerful leading-edge vortices. As a preliminary test, our numerical results show that, the shaft-torque fluctuation in the turbine's stall region can be improved from 27.8% for a straight leading-edge blade (no control) to 8.9% for the present active control; and by adjusting the control parameters, the control units nearly have not any negative effect on the blade's shaft torque under the design conditions. We believe that, as an auxiliary tool of the conventional control strategies, the present active control approach may be favorable to generate a more stable and more controllable power output for wind turbines under all operating conditions (even in the yawed inflows).

  11. (VI) from water by micro-alloyed aluminium composite (MAlC)

    African Journals Online (AJOL)

    driniev

    2004-07-03

    Jul 3, 2004 ... Abstract. This paper deals with Cr(VI) ion removal from water, by micro-alloyed aluminium composite (MAlC), under flow conditions. In a water ... Cr(VI) were below the maximal allowed concentrations for drinking water, in all model solutions. ... mucous membrane irritant and some of these hexavalent com-.

  12. Application of response surface methodology and artificial neural network: modeling and optimization of Cr(VI) adsorption process using Dowex 1X8 anion exchange resin.

    Science.gov (United States)

    Harbi, Soumaya; Guesmi, Fatma; Tabassi, Dorra; Hannachi, Chiraz; Hamrouni, Bechir

    2016-01-01

    We report the adsorption efficiency of Cr(VI) on a strong anionic resin Dowex 1X8. The Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis of this adsorbent were investigated. Response surface methodology was applied to evaluate the main effects and interactions among initial pH, initial Cr(VI) concentration, adsorbent dose and temperature. Analysis of variance depicted that resin dose and initial pH were the most significant factors. Desirability function (DF) showed that the maximum Cr(VI) removal of 95.96% was obtained at initial pH 5, initial Cr(VI) concentration of 100 mg/L, resin dose of 2 g and temperature of 283 K. Additionally, a simulated industrial wastewater containing 14.95 mg/L of Cr(VI) was treated successfully by Dowex 1X8 at optimum conditions. Same experimental design was employed to develop the artificial neural network. Both models gave a high correlation coefficient (RRSM(2) = 0.932, RANN(2) = 0.996).

  13. VI Tallinna arhitektuuritriennaal / Leonhard Lapin

    Index Scriptorium Estoniae

    Lapin, Leonhard, 1947-

    2005-01-01

    15.-17. IX Tallinnas Niguliste kirikus toimuval VI Tallinna arhitektuuritriennaalil esinevad inglise arhitektuurikriitik Peter Davey, šveitsi arhitekt Peter Zumthor, soome arhitekt Juha Leviskä, eesti arhitekt Vilen Künnapu, eesti kunstiajaloolane Juhan Maiste jt. Külastatakse KUMU, tutvutab autor Pekka Vapaavuori

  14. (VI) oxide in acetic acid

    African Journals Online (AJOL)

    The oxidation of cyclohexene by chromium (VI) oxide in aqueous and acetic media was studied. The reaction products were analysed using infra red (IR) and gas chromatography coupled with mass (GC/MS) spectroscopy. The major products of the oxidation reaction in acetic acid medium were cyclohexanol, ...

  15. Heating, Ventilation, and Air Conditioning Design Strategy for a Hot-Humid Production Builder

    Energy Technology Data Exchange (ETDEWEB)

    Kerrigan, P. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-03-01

    BSC worked directly with the David Weekley Homes - Houston division to redesign three floor plans in order to locate the HVAC system in conditioned space. The purpose of this project is to develop a cost effective design for moving the HVAC system into conditioned space. In addition, BSC conducted energy analysis to calculate the most economical strategy for increasing the energy performance of future production houses. This is in preparation for the upcoming code changes in 2015. The builder wishes to develop an upgrade package that will allow for a seamless transition to the new code mandate. The following research questions were addressed by this research project: 1. What is the most cost effective, best performing and most easily replicable method of locating ducts inside conditioned space for a hot-humid production home builder that constructs one and two story single family detached residences? 2. What is a cost effective and practical method of achieving 50% source energy savings vs. the 2006 International Energy Conservation Code for a hot-humid production builder? 3. How accurate are the pre-construction whole house cost estimates compared to confirmed post construction actual cost? BSC and the builder developed a duct design strategy that employs a system of dropped ceilings and attic coffers for moving the ductwork from the vented attic to conditioned space. The furnace has been moved to either a mechanical closet in the conditioned living space or a coffered space in the attic.

  16. 15 KJ FLASH LAMP, POWER CONDITIONING UNIT DESIGNED FOR SAFTY, RELIABILITY & MANUFACTURABILITY*

    Energy Technology Data Exchange (ETDEWEB)

    James, G; Merritt, B; Dreifuerst, G; Strickland, S

    2007-08-07

    A 15kJoule, Flash Lamp Power Conditioning Unit has been successfully designed, developed, and deployed in the National Ignition Facility (NIF) Preamplifier Modules (PAM). The primary design philosophy of this power conditioning unit (PCU) is safety, reliability, and manufacturability. Cost reduction over commercially equivalent systems was also achieved through an easily manufactured packaging design optimized to meet NIF requirements. While still maintaining low cost, the PCU design includes a robust control system, fault diagnostic system, and safety features. The pulsed power design includes 6 PFN modules, each including a dual series injection trigger transformer, that drive a total of 12 flash lamp loads. The lamps are individually triggered via a 20kV pulse produced by a 1kV, MCT switched capacitive discharge unit on the primary side of the trigger transformer. The remote control interface includes an embedded controller that captures flash lamp current wave forms and fault status for each shot. The embedded controller provides the flexibility of remotely adjusting both the main drive voltage from 1.6 to 2.5 kV and the trigger voltage from 0 to 20 kV.

  17. Design, construction and conditions of the application of unreinforced concrete final lining in conventionally driven tunnels

    Science.gov (United States)

    Faltýnek, Jan; Hořejší, Jiří; Mařík, Libor; Růžička, Pavel

    2017-09-01

    The way to an economic design in the final lining in conventionally driven tunnels lies in structural analysing based on the actually encountered geotechnical conditions. Regarding reinforced concrete structures, many standards and regulations applicable to designing and building structures and taking them over by the client before their commissioning and before the end of the warranty period respectively exist in the Czech Republic. If the local conditions allow it, it is possible to design the final lining as an unreinforced concrete structure. In such a case it is necessary to take the differences into consideration in the structural design and in the possibilities of the lining behaviour and to set criteria for taking over the lining allowing for its use. Setting too stringent criteria for cracking can lead to an increase in the contract price, either because of the necessity for reinforcing the lining or because of the fact that the contractor reduces the risk by incorporating the assumed cost of repairs into the total cost. The paper describes basic differences in the approach to reinforced concrete and unreinforced concrete linings, the possibilities of limiting formation of cracks by means of the concrete mix design, by selection of the technological procedure of the work and the method of curing after stripping. The text contains a comparison of criteria for assessing the surface of an unreinforced concrete lining with criteria in foreign regulations.

  18. [Optimization of water extraction condition of LiYan granule by Doehlert design].

    Science.gov (United States)

    Tao, Jian-fei; Chen, Li-na; Du, Shu-hu

    2007-11-01

    To study optimal water extraction condition of LiYan granule. HPLC methods were developed for the determination of irisfloremin in LiYan granule. The contents of irisfloremin and extraction rate were selected as assessment indices. Three factors were studied by Doehlert design, including water-adding amount, decoction time and times of decoction. The optimal extracting condition was water consumed as 8 times of curd herb, and 3 times for 2 hours each time. The water extraction process is feasible, and the experiment result can provide basic and instruction data for the ascertainment of water extraction process of LiYan granule.

  19. Vertical flow constructed wetlands for domestic wastewater treatment on tropical conditions: effect of several design parameters

    DEFF Research Database (Denmark)

    Bohorquez, Eliana; Paredes, Diego; Arias, Carlos Alberto

    Vertical flow constructed wetlands (VFWC) design and operation takes into account several variables which affect performance its performance. These aspects had been evaluated and documented among others in countries like USA, Denmark, Austria. In contrast, VFCW had not been studied in tropical...... countries and, specifically in Colombia, design and operation parameters are not defined yet. The objective of this study was evaluate the effects of filter medium, the feeding frequency and Heliconia psittacorum presence, a typical local plant, on the domestic wastewater treatment in tropical conditions....

  20. Electrochemical synthesis of ferrate(VI) using sponge iron anode and oxidative transformations of antibiotic and pesticide.

    Science.gov (United States)

    Sun, Xuhui; Zu, Kexin; Liang, He; Sun, Lin; Zhang, Lingyun; Wang, Chuanyi; Sharma, Virender K

    2017-09-06

    Passivation of anode is a main challenge in the electrochemical synthesis of ferrate(VI) (Fe(VI)O4(2-), Fe(VI)). A series of electrochemical approaches were employed including polarization curve, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS) to analyze the physicochemical processes involved in electrochemical synthesis of Fe(VI) using sponge iron and cast iron anodes. The results demonstrate that the sponge iron anode achieved higher yield of Fe(VI) compared to grey cast iron anode. The optimum condition to generate Fe(VI) using sponge iron was 35-50°C and 30mA/cm(2). Significantly, the sponge iron anode could generate Fe(VI) for a long duration (>10h) under these conditions; possibly suitable for large scale synthesis of Fe(VI). The prepared Fe(VI) solution was used to treat antibiotic (sulfamethoxazole (SMX)) and pesticide (atrazine (ATZ)) in water. At a molar ratio of Fe(VI) to SMX as 20:1 in the pH range from 5.0 to 9.0, almost complete oxidative transformation of SMX could be obtained. Comparatively, oxidative transformation of ATZ was incomplete (∼70%) even when [Fe(VI)]:[ATZ]=87 at pH 5.0-9.0. Fluorescence spectra and cytotoxicity studies suggest that the oxidative transformation products of both SMX and ATZ possess lower toxicity than the parent antibiotic and pesticide, respectively. Copyright © 2017. Published by Elsevier B.V.

  1. Conceptual Design of Automotive Compressor for Integrated Portable Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Ishak Muhammad Ikman

    2017-01-01

    Full Text Available This study introduces a new concept of portable air conditioner which integrated with some available components in automotive air conditioning system. This new idea intends to solve the storage problems as well as to reduce the price of current portable air conditioner since some devices could directly be used from the automotive air conditioning system. The primary emphasis of this study was on the modification of automotive compressor design so as the system may alternately be operated. The length of conventional compressor shaft is extended to place an additional clutch pulley, a drive plate and a clutch coil. The new concept particularly the shaft and pulley were analysed through slope deflection and computational finite element analyses. The result of engineering analyses exhibited that the new design of compressor shaft and clutch pulleys promote a low risk of failure as the data values recorded are lower than the critical value for each criterion investigated.

  2. 29 CFR 1926.1126 - Chromium (VI).

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Chromium (VI). 1926.1126 Section 1926.1126 Labor... Chromium (VI). (a) Scope. (1) This standard applies to occupational exposures to chromium (VI) in all forms... objective data demonstrating that a material containing chromium or a specific process, operation, or...

  3. 29 CFR 1915.1026 - Chromium (VI).

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Chromium (VI). 1915.1026 Section 1915.1026 Labor... § 1915.1026 Chromium (VI). (a) Scope. (1) This standard applies to occupational exposures to chromium (VI... cement; or (4) Where the employer has objective data demonstrating that a material containing chromium or...

  4. The Role of Biogeochemical Dynamics in the Alteration of Uranium Solid Phases Under Oxic Conditions.

    Science.gov (United States)

    Letain, T. E.; Silva, R. J.; Nitsche, H.; Nitsche, H.; Hazen, T. C.; Clark, S. B.; Douglas, M.; Gillaspie, C.; Knopp, R.; Panak, P. J.

    2001-12-01

    Microbial reduction of uranium has been shown to lower groundwater concentrations of uranium in anoxic systems, but such biological alterations must be considered temporary unless long-term anoxia can be guaranteed. Under oxic conditions, the more soluble higher oxidation state of uranium, e.g. the uranyl cation UO2(2+), is thermodynamically favored. For example, in U ore deposits in which uraninite - consisting of reduced U(IV) as UO(2+x) - is the parent material, exposure to oxidizing conditions results in alteration to U(VI) minerals, with the U(VI)-phosphates frequently defining the boundaries of the ore body. U(VI)-phosphates are of interest because of their relatively low solubilities compared to other U(VI) solid phases. Since microorganisms are undoubtedly present in such ore deposits, they likely play a role in the formation of U(VI)-phosphate solid phases. To assist the U.S. Department of Energy (DOE) with long-term stewardship issues associated with bioremediation of uranium, the overall goal of this project is to work with model biological systems to define the mechanisms by which microorganisms facilitate the formation of U(VI)-phosphate solid phases. This information can then be used by DOE to design remediation systems that stimulate biological activity to favor the formation of U(VI)-phosphate phases. In this project, we are investigating the role of some individual bacterial strains (Bacillus sphaericus and Shewanella putrefaciens) as well as microbial consortia isolated from the NABIR Field Research Center at Oak Ridge National Laboratory on the alteration of U(VI) solid phases. These strains were selected to reflect a variety of subsurface conditions including aerobic, microaerophilic, and episodically anaerobic. These bacteria or similar species are found throughout subsurface environments. They are believed to influence actinide geochemistry through various mechanisms. These mechanisms are not independent of one another, and together they

  5. conditions

    Directory of Open Access Journals (Sweden)

    M. Venkatesulu

    1996-01-01

    Full Text Available Solutions of initial value problems associated with a pair of ordinary differential systems (L1,L2 defined on two adjacent intervals I1 and I2 and satisfying certain interface-spatial conditions at the common end (interface point are studied.

  6. Kinetics and Products of Chromium(VI) Reduction by Iron(II/III)-Bearing Clay Minerals.

    Science.gov (United States)

    Joe-Wong, Claresta; Brown, Gordon E; Maher, Kate

    2017-09-05

    Hexavalent chromium is a water-soluble pollutant, the mobility of which can be controlled by reduction of Cr(VI) to less soluble, environmentally benign Cr(III). Iron(II/III)-bearing clay minerals are widespread potential reductants of Cr(VI), but the kinetics and pathways of Cr(VI) reduction by such clay minerals are poorly understood. We reacted aqueous Cr(VI) with two abiotically reduced clay minerals: an Fe-poor montmorillonite and an Fe-rich nontronite. The effects of ionic strength, pH, total Fe content, and the fraction of reduced structural Fe(II) [Fe(II)/Fe(total)] were examined. The last variable had the largest effect on Cr(VI) reduction kinetics: for both clay minerals, the rate constant of Cr(VI) reduction varies by more than 3 orders of magnitude with Fe(II)/Fe(total) and is described by a linear free energy relationship. Under all conditions examined, Cr and Fe K-edge X-ray absorption near-edge structure spectra show that the main Cr-bearing product is a Cr(III)-hydroxide and that Fe remains in the clay structure after reacting with Cr(VI). This study helps to quantify our understanding of the kinetics of Cr(VI) reduction by Fe(II/III)-bearing clay minerals and may improve predictions of Cr(VI) behavior in subsurface environments.

  7. Improvement of matrix condition of Hybrid, space variant optics by the means of parallel optics design.

    Science.gov (United States)

    Klapp, Iftach; Mendlovic, David

    2009-07-06

    The problem of image restoration of space variant blur is common and important. One of the most useful descriptions of this problem is in its algebraic form I=H*O, where O is the object represented as a column vector, I is the blur image represented as a column vector and H is the PSF matrix that represents the optical system. When inverting the problem to restore the geometric object from the blurred image and the known system matrix, restoration is limited in speed and quality by the system condition. Current optical design methods focus on image quality, therefore if additional image processing is needed the matrix condition is taken "as is". In this paper we would like to present a new optical approach which aims to improve the system condition by proper optical design. In this new method we use Singular Value Decomposition (SVD) to define the weak parts of the matrix condition. We design a second optical system based on those weak SVD parts and then we add the second system parallel to the first one. The original and second systems together work as an improved parallel optics system. Following that, we present a method for designing such a "parallel filter" for systems with a spread SVD pattern. Finally we present a study case in which by using our new method we improve a space variant image system with an initial condition number of 8.76e4, down to a condition number of 2.29e3. We use matrix inversion to simulate image restoration. Results show that the new parallel optics immunity to Additive White Gaussian Noise (AWGN) is much better then that of the original simple lens. Comparing the original and the parallel optics systems, the parallel optics system crosses the MSEIF=0 [db] limit in SNR value which is more than 50db lower then the SNR value in the case of the original simple lens. The new parallel optics system performance is also compared to another method based on the MTF approach.

  8. Isolation of a star-shaped uranium(V/VI) cluster from the anaerobic photochemical reduction of uranyl(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Chatelain, Lucile; White, Sarah; Scopelliti, Rosario; Mazzanti, Marinella [Ecole Polytechnique Federale de Lausanne (EPFL) (Switzerland). Inst. de Sciences et Ingenierie Chimiques

    2016-11-07

    Actinide oxo clusters are an important class of compounds due to their impact on actinide migration in the environment. The photolytic reduction of uranyl(VI) has potential application in catalysis and spent nuclear fuel reprocessing, but the intermediate species involved in this reduction have not yet been elucidated. Here we show that the photolysis of partially hydrated uranyl(VI) in anaerobic conditions leads to the reduction of uranyl(VI), and to the incorporation of the resulting U{sup V} species into the stable mixed-valent star-shaped U{sup VI}/U{sup V} oxo cluster [U(UO{sub 2}){sub 5}(μ{sub 3}-O){sub 5}(PhCOO){sub 5}(Py){sub 7}]. This cluster is only the second example of a U{sup VI}/U{sup V} cluster and the first one associating uranyl groups to a non-uranyl(V) center. The U{sup V} center in 1 is stable, while the reaction of uranyl(V) iodide with potassium benzoate leads to immediate disproportionation and formation of the U{sub 12}{sup IV}U{sub 4}{sup V}O{sub 24} cluster {[K(Py)_2]_2[K(Py)]_2[U_1_6O_2_4(PhCOO)_2_4(Py)_2]}.

  9. Applicability of a submersible microbial fuel cell for Cr(VI) detection in water.

    Science.gov (United States)

    Chung, Hyeonyong; Ju, Won Jung; Jho, Eun Hea; Nam, Kyoungphile

    2016-11-01

    Two-chamber microbial fuel cells (MFCs) were used to study the applicability of MFCs for hexavalent chromium (Cr(VI)) detection in water. The microbial acetate oxidation in the anode and the Cr(VI) reduction in the cathode together generated voltages, which were used to indicate the change in Cr(VI) concentrations of the cathode under varying conditions of pH, ionic strength, co-existing Fe(II) concentration, and organic matter concentration. The MFC-based Cr(VI) detector showed a significant change in voltage with increasing Cr(VI) concentration at pH 1 and 2, but not at higher pH conditions. The detector also successfully measured the changes in Cr(VI) concentration at a range of ionic strength (i.e., 10-300 mM), and in the presence of different concentrations of fulvic acid (0-50 mg/L), which was used as a surrogate of organic matters, without interference. The Cr(VI) detection was not interfered by the presence of Fe(II) at the Cr(VI)/Fe(II) ratio of 1:1 and 1:15, but it was interfered at higher ratios (i.e., 1:164 and 1:848). The detector could measure the Cr(VI) concentration from 0.1 to 15 mg/L at pH 2. Overall, the MFC-based Cr(VI) detector may be applied to meet the growing need of real-time Cr(VI) monitoring in water.

  10. Design and Evaluation of Composite Fuselage Panels Subjected to Combined Loading Conditions

    Science.gov (United States)

    Ambur, Damodar R.; Rouse, Marshall

    1998-01-01

    Methodologies used in industry for designing transport aircraft composite fuselage structures are discussed. Several aspects of the design methodologies are based on assumptions from metallic fuselage technology which requires that full-scale structures be tested with the actual loading conditions to validate the designs. Composite panels which represent crown and side regions of a fuselage structure are designed using this approach and tested in biaxial tension. Descriptions of the state-of-the-art test facilities used for this structural evaluation are presented. These facilities include a pressure-box test machine and a D-box test fixture in a combined loads test machine which are part of a Combined Loads Test System (COLTS). Nonlinear analysis results for a reference shell and a stiffened composite panel tested in the pressure-box test machine with and without damage are presented. The analytical and test results are compared to assess the ability of the pressure-box test machine to simulate a shell stress state with and without damage. A combined loads test machine for testing aircraft primary structures is described. This test machine includes a D-box test fixture to accommodate curved stiffened panels and the design features of this test fixture are presented. Finite element analysis results for a curved panel to be tested in the D-box test fixture are also discussed.

  11. Hvad bruger vi tiden til?

    DEFF Research Database (Denmark)

    Brichet, Nathalia Sofie; Hastrup, Frida

    2016-01-01

    I denne artikel kaster vi et antropologisk blik på samtidsarkæologi ved at diskutere måder, hvorpå antropologiske analyser kan adressere tid, fortidige hændelser og historiske processer. Vi argumenterer for, at en radikal nutidsorientering er en afgørende kvalitet ved det antropologiske feltarbej...... komplicerer en ide om fortidige (gamle eller nyere) objekter som nogle, der kan udgraves......., hvis sigte det er løbende at generere sit materiale nu og her med henblik på at skabe nye forståelser, historier og forslag til mangeartede sammenhænge. En implikation af dette er, at uanset hvor ’historisk’ et antropologisk materiale end måtte være, må det altid ses som samtidigt og ufærdigt, hvilket...

  12. Isolation and characterization of Cr(VI) reducing Cellulomonas spp. from subsurface soils: Implications for long-term chromate reduction

    Energy Technology Data Exchange (ETDEWEB)

    S. Viamajala; W. Smith; R. Sani; W. Apel; J. Petersen; A. Neal; F. Roberto; D. Newby; B. Peyton

    2007-02-01

    Microbial enrichments from Cr(VI) contaminated and uncontaminated US Department of Energy Hanford Site sediments produced Cr(VI) reducing consortia when grown in the presence of Cr(VI) with acetate, D-xylose or glycerol as a carbon and energy source. Eight of the nine isolates from the consortia were Gram positive and four of these were identified by 16S rRNA sequence homology and membrane fatty acid composition as belonging to the genus Cellulomonas. Two strains, ES6 and WS01, were further examined for their ability to reduce Cr(VI) under growth and non-growth conditions. During fermentative growth on D-xylose, ES6 and WS01 decreased aqueous Cr(VI) concentrations from 0.04 mM Cr(VI) to below the detection limit (0.002 mM Cr(VI)) in less than three days and retained their ability to reduce Cr(VI) even after four months of incubation. Washed ES6 and WS01 cells also reduced Cr(VI) under non-growth conditions for over four months, both with and without the presence of an exogenous electron donor. K-edge XANES spectroscopy confirmed the reduction of Cr(VI) to Cr(III). The ability to reduce Cr(VI) after growth had stopped and in the absence of an external electron donor, suggests that stimulation of these types of organisms may lead to effective long-term, in situ passive reactive barriers for Cr(VI) removal. Our results indicate that Cr(VI) reduction by indigenous Cellulomonas spp. may be a potential method of in situ bioremediation of Cr(VI) contaminated sediment and groundwater.

  13. Isolation and characterization of Cr(VI) reducing Cellulomonas spp. from subsurface soils: implications for long-term chromate reduction.

    Science.gov (United States)

    Viamajala, Sridhar; Smith, William A; Sani, Rajesh K; Apel, William A; Petersen, James N; Neal, Andrew L; Roberto, F F; Newby, D T; Peyton, Brent M

    2007-02-01

    Microbial enrichments from Cr(VI) contaminated and uncontaminated US Department of Energy Hanford Site sediments produced Cr(VI) reducing consortia when grown in the presence of Cr(VI) with acetate, D-xylose or glycerol as a carbon and energy source. Eight of the nine isolates from the consortia were Gram positive and four of these were identified by 16S rRNA sequence homology and membrane fatty acid composition as belonging to the genus Cellulomonas. Two strains, ES6 and WS01, were further examined for their ability to reduce Cr(VI) under growth and non-growth conditions. During fermentative growth on D-xylose, ES6 and WS01 decreased aqueous Cr(VI) concentrations from 0.04 mM Cr(VI) to below the detection limit (0.002 mM Cr(VI)) in less than three days and retained their ability to reduce Cr(VI) even after four months of incubation. Washed ES6 and WS01 cells also reduced Cr(VI) under non-growth conditions for over four months, both with and without the presence of an exogenous electron donor. K-edge XANES spectroscopy confirmed the reduction of Cr(VI) to Cr(III). The ability to reduce Cr(VI) after growth had stopped and in the absence of an external electron donor, suggests that stimulation of these types of organisms may lead to effective long-term, in situ passive reactive barriers for Cr(VI) removal. Our results indicate that Cr(VI) reduction by indigenous Cellulomonas spp. may be a potential method of in situ bioremediation of Cr(VI) contaminated sediment and groundwater.

  14. The influence of kinematic conditions and design on the wear of patella-femoral replacements.

    Science.gov (United States)

    Maiti, Raman; Fisher, John; Rowley, Liam; Jennings, Louise M

    2014-02-01

    The success rate of patella-femoral arthroplasty varies between 44% and 90% in 17 years of follow-up. Several studies have been performed previously for assessing the surface wear in the patella-femoral joint. However, they have not included all six degrees of freedom. The aim of this study was to develop a six-axis patella-femoral joint simulator to assess the wear rate for two patellae designs (round and oval dome) at different kinematic conditions. An increase in patellar rotation from 1° to 4° led to a significantly (p0.08). The increase in wear rate was likely due to the higher cross shear. A decrease in patellar medial lateral displacement from passive to constrained resulted in a nonsignificant reduction in wear (p>0.06). There was no significant difference in wear rate between the two patellae designs (p>0.28). The volumetric wear under all conditions was positively correlated with the level of passive patellar tilt (rho>0.8). This is the first report of preclinical wear simulation of patella-femoral joint in a six-axis simulator under different kinematic conditions.

  15. Numerical Approach for Goaf-Side Entry Layout and Yield Pillar Design in Fractured Ground Conditions

    Science.gov (United States)

    Jiang, Lishuai; Zhang, Peipeng; Chen, Lianjun; Hao, Zhen; Sainoki, Atsushi; Mitri, Hani S.; Wang, Qingbiao

    2017-11-01

    Entry driven along goaf-side (EDG), which is the development of an entry of the next longwall panel along the goaf-side and the isolation of the entry from the goaf with a small-width yield pillar, has been widely employed in China over the past several decades . The width of such a yield pillar has a crucial effect on EDG layout in terms of the ground control, isolation effect and resource recovery rate. Based on a case study, this paper presents an approach for evaluating, designing and optimizing EDG and yield pillar by considering the results from numerical simulations and field practice. To rigorously analyze the ground stability, the numerical study begins with the simulation of goaf-side stress and ground conditions. Four global models with identical conditions, except for the width of the yield pillar, are built, and the effect of pillar width on ground stability is investigated by comparing aspects of stress distribution, failure propagation, and displacement evolution during the entire service life of the entry. Based on simulation results, the isolation effect of the pillar acquired from field practice is also considered. The suggested optimal yield pillar design is validated using a field test in the same mine. Thus, the presented numerical approach provides references and can be utilized for the evaluation, design and optimization of EDG and yield pillars under similar geological and geotechnical circumstances.

  16. “Stereoscopic” 2D super-microporous phosphazene-based covalent organic framework: Design, synthesis and selective sorption towards uranium at high acidic condition

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Shuang; Zhao, Xiaosheng; Li, Bo; Bai, Chiyao; Li, Yang; Wang, Lei; Wen, Rui; Zhang, Meicheng; Ma, Lijian; Li, Shoujian, E-mail: sjli000616@scu.edu.cn

    2016-08-15

    Highlights: • Phosphorus element was first introduced into covalent organic frameworks (COFs). • Monomer in C{sub 3}-like spatial configuration was first used to construct COF materials. • A new 2D super-microporous phosphazene-based sorbent (MPCOF) was synthesized. • Separation of U (VI) by MPCOF at high acidic media (up to 1M HNO{sub 3}) was achieved. • Selectivity for U (VI) separation from multi-ion solution can reach unreported 92%. - Abstract: So far, only five primary elements (C, H, O, N and B) and two types of spatial configuration (C{sub 2}–C{sub 4}, C{sub 6} and T{sub d}) are reported to build the monomers for synthesis of covalent organic frameworks (COFs), which have partially limited the route selection for accessing COFs with new topological structure and novel properties. Here, we reported the design and synthesis of a new “stereoscopic” 2D super-microporous phosphazene-based covalent organic framework (MPCOF) by using hexachorocyclotriphosphazene (a P-containing monomer in a C{sub 3}-like spatial configuration) and p-phenylenediamine (a linker). The as-synthesized MPCOF shows high crystallinity, relatively high heat and acid stability and distinctive super-microporous structure with narrow pore-size distributions ranging from 1.0–2.1 nm. The results of batch sorption experiments with a multi-ion solution containing 12 co-existing cations show that in the pH range of 1–2.5, MPCOF exhibits excellent separation efficiency for uranium with adsorption capacity more than 71 mg/g and selectivity up to record-breaking 92%, and furthermore, an unreported sorption capacity (>50 mg/g) and selectivity (>60%) were obtained under strong acidic condition (1 M HNO{sub 3}). Studies on sorption mechanism indicate that the uranium separation by MPCOF in acidic solution is realized mainly through both intra-particle diffusion and size-sieving effect.

  17. Heating, Ventilation, and Air Conditioning Design Strategy for a Hot-Humid Production Builder

    Energy Technology Data Exchange (ETDEWEB)

    Kerrigan, P. [Building Science Corporation, Somerville, MA (United States)

    2014-03-01

    Building Science Corporation (BSC) worked directly with the David Weekley Homes - Houston division to develop a cost-effective design for moving the HVAC system into conditioned space. In addition, BSC conducted energy analysis to calculate the most economical strategy for increasing the energy performance of future production houses in preparation for the upcoming code changes in 2015. This research project addressed the following questions: 1. What is the most cost effective, best performing and most easily replicable method of locating ducts inside conditioned space for a hot-humid production home builder that constructs one and two story single family detached residences? 2. What is a cost effective and practical method of achieving 50% source energy savings vs. the 2006 International Energy Conservation Code for a hot-humid production builder? 3. How accurate are the pre-construction whole house cost estimates compared to confirmed post construction actual cost?

  18. Identifying Personal Goals of Patients With Long Term Condition: A Service Design Thinking Approach.

    Science.gov (United States)

    Lee, Eunji; Gammon, Deede

    2017-01-01

    Care for patients with long term conditions is often characterized as fragmented and ineffective, and fails to engage the resources of patients and their families in the care process. Information and communication technology can potentially help bridge the gap between patients' lives and resources and services provided by professionals. However, there is little attention on how to identify and incorporate the patients' individual needs, values, preferences and care goals into the digitally driven care settings. We conducted a case study with healthcare professionals and patients participated applying a service design thinking approach. The participants could elaborate some personal goals of patients with long term condition which can potentially be incorporated in digitally driven care plans using examples from their own experiences.

  19. LHC Beam Dump Design Study - Part III : Off-normal operating conditions

    CERN Document Server

    Bruno, L; Ross, M; Sala, P

    2000-01-01

    The LHC beam dump design study has been preliminarily substantiated by energy deposition simulations (Part I) and heat transfer analyses (Part II). The present report is devoted to the abnormal operating conditions induced by a malfunction of the beam diluters. A general approach to the analysis of off-normal operation is presented, which is derived from standard design norms adopted in the nuclear industry. Attention is focused mainly on the carbon core, which is longitudinally split into segments of different density in order to better distribute the deposited energy. The maximum energy density it absorbs decreases by at least 33%, compared to a uniform standard density carbon core. This structure may sustain any partial sweep failure without major damage, up to the ultimate beam intensity and energy. To minimise the risks inherent in a fully unswept beam, a sacrificial graphite mandrel will be placed on the core axis, surrounded by a thick high strength carbon-carbon composite tube. With this arrangement, ...

  20. Condition Monitoring System Designing of GIS Based on Trip/close Coil Current

    Science.gov (United States)

    Wei, Dongliang; Wang, Zhi; Xue, Feng; Li, Haitao

    2017-05-01

    In this article, the types and characteristics of the faults from GIS were analyzed that the major failures were caused by its operating mechanism and auxiliary control circuits. While a useful parameter to effectively diagnose the mechanical failures of GIS is the trip/close coil current which is accessible and easy-to-measure. A portable system has been design to monitor the condition of GIS by detecting the coil current. This system was fulfilled with functions like signal sampling, processing, transmitting and performing. DSP and ARM11 carrying WINCE 6.0 have been used to construct the system. The feasibility and reliability were validated through several repeated experiments.

  1. A design proposal of real-time monitoring stations: implementation and performance in contrasting environmental conditions

    Directory of Open Access Journals (Sweden)

    Jose González

    2012-09-01

    Full Text Available With the aim of creating a real-time monitoring network for both oceanographic and meteorological data, a monitoring station conceptual design was developed. A common framework for software and electronics was adapted to different environmental conditions using two buoy approaches: one intended for oceanic waters, to be moored up to 30-40 m depth, where waves are the critical design factor, and one for continental waters (rivers, lakes and the inner part of estuaries, where currents are the critical design factor. When structures such as bridges are present in the area, the monitoring station can be installed on these structures, thus reducing its impact and increasing safety. In this paper, the design, implementation, operation and performance of these stations are described. A reliability index is calculated for the longest time series of the three related deployment options on the Galician coast: Cíes (oceanic buoy in front of the Ría de Vigo, Catoira (continental buoy in the Ulla river and Cortegada (installation in a bed in the Ría de Arousa.

  2. Identifying Watershed, Landscape, and Engineering Design Factors that Influence the Biotic Condition of Restored Streams

    Directory of Open Access Journals (Sweden)

    Barbara Doll

    2016-04-01

    Full Text Available Restored stream reaches at 79 sites across North Carolina were sampled for aquatic macroinvertebrates using a rapid bioassessment protocol. Morphological design parameters and geographic factors, including watershed and landscape parameters (e.g., valley slope, substrate, were also compiled for these streams. Principal component regression analyses revealed correlations between design and landscape variables with macroinvertebrate metrics. The correlations were strengthened by adding watershed variables. Ridge regression was used to find the best-fit model for predicting dominant taxa from the “pollution sensitive” orders of Ephemeroptera (mayflies, Plecoptera (stoneflies, and Trichoptera (caddisflies, or EPT taxa, resulting in coefficient weights that were most interpretable relative to site selection and design parameters. Results indicate that larger (wider streams located in the mountains and foothills where there are steeper valleys, larger substrate, and undeveloped watersheds are expected to have higher numbers of dominant EPT taxa. In addition, EPT taxa numbers are positively correlated with accessible floodplain width and negatively correlated with width-to-depth ratio and sinuosity. This study indicates that both site selection and design should be carefully considered in order to maximize the resulting biotic condition and associated potential ecological uplift of the stream.

  3. Perfect Reconstruction Conditions and Design of Oversampled DFT-Modulated Transmultiplexers

    Directory of Open Access Journals (Sweden)

    Siohan Pierre

    2006-01-01

    Full Text Available This paper presents a theoretical analysis of oversampled complex modulated transmultiplexers. The perfect reconstruction (PR conditions are established in the polyphase domain for a pair of biorthogonal prototype filters. A decomposition theorem is proposed that allows it to split the initial system of PR equations, that can be huge, into small independent subsystems of equations. In the orthogonal case, it is shown that these subsystems can be solved thanks to an appropriate angular parametrization. This parametrization is efficiently exploited afterwards, using the compact representation we recently introduced for critically decimated modulated filter banks. Two design criteria, the out-of-band energy minimization and the time-frequency localization maximization, are examined. It is shown, with various design examples, that this approach allows the design of oversampled modulated transmultiplexers, or filter banks with a thousand carriers, or subbands, for rational oversampling ratios corresponding to low redundancies. Some simulation results, obtained for a transmission over a flat fading channel, also show that, compared to the conventional OFDM, these designs may reduce the mean square error.

  4. Design Criteria, Operating Conditions, and Nickel-Iron Hydroxide Catalyst Materials for Selective Seawater Electrolysis.

    Science.gov (United States)

    Dionigi, Fabio; Reier, Tobias; Pawolek, Zarina; Gliech, Manuel; Strasser, Peter

    2016-05-10

    Seawater is an abundant water resource on our planet and its direct electrolysis has the advantage that it would not compete with activities demanding fresh water. Oxygen selectivity is challenging when performing seawater electrolysis owing to competing chloride oxidation reactions. In this work we propose a design criterion based on thermodynamic and kinetic considerations that identifies alkaline conditions as preferable to obtain high selectivity for the oxygen evolution reaction. The criterion states that catalysts sustaining the desired operating current with an overpotential <480 mV in alkaline pH possess the best chance to achieve 100 % oxygen/hydrogen selectivity. NiFe layered double hydroxide is shown to satisfy this criterion at pH 13 in seawater-mimicking electrolyte. The catalyst was synthesized by a solvothermal method and the activity, surface redox chemistry, and stability were tested electrochemically in alkaline and near-neutral conditions (borate buffer at pH 9.2) and under both fresh seawater conditions. The Tafel slope at low current densities is not influenced by pH or presence of chloride. On the other hand, the addition of chloride ions has an influence in the temporal evolution of the nickel reduction peak and on both the activity and stability at high current densities at pH 9.2. Faradaic efficiency close to 100 % under the operating conditions predicted by our design criteria was proven using in situ electrochemical mass spectrometry. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The Ability of Benzoic Acid to Reduce Cr(VI Heavy Metal Content in Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Anugrah Windy Mustikarini

    2015-12-01

    Full Text Available Chromium (VI is an ionic heavy metal which has to be handled properly when dissolved in water due to its toxicity, corosive, carsinogenic activity.. According to the State Minister for Population and Environment’s regulation, the quality standards of waste water, which is allowed to be discharge on surface water contains Cr(VI is 0.05-1 mg/L. This research used benzoic acid which is a kind of organic acid to reduce Cr(VI content in water. Benzoic acid has an active carboxyl group which interact this metal. This paper, the elimination of Cr(VI using benzoic acid is undertaken through pH adjustment by regulating with phosphoric acid. The result showed the best condition to reducing Cr(VI content 41.99% when 400 ppm of benzoic acid and pH 7 was applied, respectively.

  6. Performance of R-410A Alternative Refrigerants in a Reciprocating Compressor Designed for Air Conditioning Applications

    Energy Technology Data Exchange (ETDEWEB)

    Shrestha, Som S [ORNL; Vineyard, Edward Allan [ORNL; Mumpower, Kevin [Bristol Compressors International, Inc.

    2016-01-01

    In response to environmental concerns raised by the use of refrigerants with high Global Warming Potential (GWP), the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) has launched an industry-wide cooperative research program, referred to as the Low-GWP Alternative Refrigerants Evaluation Program (AREP), to identify and evaluate promising alternative refrigerants for major product categories. After successfully completing the first phase of the program in December 2013, AHRI launched a second phase of the Low-GWP AREP in 2014 to continue research in areas that were not previously addressed, including refrigerants in high ambient conditions, refrigerants in applications not tested in the first phase, and new refrigerants identified since testing for the program began. Although the Ozone Depletion Potential of R-410A is zero, this refrigerant is under scrutiny due to its high GWP. Several candidate alternative refrigerants have already demonstrated low global warming potential. Performance of these low-GWP alternative refrigerants is being evaluated for Air conditioning and heat pump applications to ensure acceptable system capacity and efficiency. This paper reports the results of a series of compressor calorimeter tests conducted for the second phase of the AREP to evaluate the performance of R-410A alternative refrigerants in a reciprocating compressor designed for air conditioning systems. It compares performance of alternative refrigerants ARM-71A, L41-1, DR-5A, D2Y-60, and R-32 to that of R-410A over a wide range of operating conditions. The tests showed that, in general, cooling capacities were slightly lower (except for the R-32), but energy efficiency ratios (EER) of the alternative refrigerants were comparable to that of R-410A.

  7. Failed engine designs - unsuitable designs or changing boundary conditions?; Gescheiterte Motorkonzeptionen - ungeeignete Konstruktionen oder Wandel der Randbedingungen?

    Energy Technology Data Exchange (ETDEWEB)

    Zima, S. [Fachhochschule Giessen-Friedberg (Germany). Fachbereich Maschinenbau, Giessereitechnik und Werkstofftechnologie

    1997-11-01

    In the history of engine development many different types of engine design have appeared. This constructional diversity is the result of complex interdependencies and the aims, influences and boundary conditions pertaining at the time. Since nowadays only single acting engines with crankshaft assembly and poppet valve mechanism are built - with four or two strokes - it is interesting to examine the reasons for the failure of earlier engine concepts. A review of these engines not only provides information on their cinematic, constructional and functional peculiarities, but also gives an insight into the appearance and disappearance, success and failure of technical concepts. (orig.) [Deutsch] Im Verlauf der Motorenentwicklung sind viele Bauarten entstanden. Diese konstruktive Vielfalt ist das Ergebnis komplexer Zusammenhaenge von Zielvorgaben, Randbedingungen und anderen Einfluessen. Da heute nur noch einfachwirkende Motoren mit Kurbeltrieb und Ventilsteuerung - nach dem Vier- oder Zweitaktprinzip arbeitend - gebaut werden, stellt sich die Frage nach den Gruenden fuer das Scheitern frueherer Motorkonzepte. Ein Rueckblick auf solche Motoren zeigt nicht nur nicht ihre kinematischen, konstruktiven und betriebsmaessigen Besonderheiten, sondern vermittelt auch Einblicke in Entstehen und Verschwinden, Erfolg und Misserfolg von technischen Loesungen. (orig.)

  8. Iterative Design and Usability Testing of the Imhere System for Managing Chronic Conditions and Disability

    Science.gov (United States)

    FAIRMAN, ANDREA D.; YIH, ERIKA T.; MCCOY, DANIEL F.; LOPRESTI, EDMUND F.; MCCUE, MICHAEL P.; PARMANTO, BAMBANG; DICIANNO, BRAD E.

    2016-01-01

    A novel mobile health platform, Interactive Mobile Health and Rehabilitation (iMHere), is being developed to support wellness and self-management among people with chronic disabilities. The iMHere system currently includes a smartphone app with six modules for use by persons with disabilities and a web portal for use by medical and rehabilitation professionals or other support personnel. Our initial clinical research applying use of this system provides insight into the feasibility of employing iMHere in the development of self-management skills in young adults (ages 18–40 years) with spina bifida (SB) (Dicianno, Fairman, et al., 2015). This article describes the iterative design of the iMHere system including usability testing of both the app modules and clinician portal. Our pilot population of persons with SB fostered the creation of a system appropriate for people with a wide variety of functional abilities and needs. As a result, the system is appropriate for use by persons with various disabilities and chronic conditions, not only SB. In addition, the diversity of professionals and support personnel involved in the care of persons with SB also enabled the design and implementation of the iMHere system to meet the needs of an interdisciplinary team of providers who treat various conditions. The iMHere system has the potential to foster communication and collaboration among members of an interdisciplinary healthcare team, including individuals with chronic conditions and disabilities, for a client-centered approach to support self-management skills. PMID:27563387

  9. Preliminary Two-Phase Terry Turbine Nozzle Models for RCIC Off-Design Operation Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Haihua [Idaho National Lab. (INL), Idaho Falls, ID (United States); O' Brien, James [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-06-12

    This report presents the effort to extend the single-phase analytical Terry turbine model to cover two-phase off-design conditions. The work includes: (1) adding well-established two-phase choking models – the Isentropic Homogenous Equilibrium Model (IHEM) and Moody’s model, and (2) theoretical development and implementation of a two-phase nozzle expansion model. The two choking models provide bounding cases for the two-phase choking mass flow rate. The new two-phase Terry turbine model uses the choking models to calculate the mass flow rate, the critical pressure at the nozzle throat, and steam quality. In the divergent stage, we only consider the vapor phase with a similar model for the single-phase case by assuming that the liquid phase would slip along the wall with a much slower speed and will not contribute the impulse on the rotor. We also modify the stagnation conditions according to two-phase choking conditions at the throat and the cross-section areas for steam flow at the nozzle throat and at the nozzle exit. The new two-phase Terry turbine model was benchmarked with the same steam nozzle test as for the single-phase model. Better agreement with the experimental data is observed than from the single-phase model. We also repeated the Terry turbine nozzle benchmark work against the Sandia CFD simulation results with the two-phase model for the pure steam inlet nozzle case. The RCIC start-up tests were simulated and compared with the single-phase model. Similar results are obtained. Finally, we designed a new RCIC system test case to simulate the self-regulated Terry turbine behavior observed in Fukushima accidents. In this test, a period inlet condition for the steam quality varying from 1 to 0 is applied. For the high quality inlet period, the RCIC system behaves just like the normal operation condition with a high pump injection flow rate and a nominal steam release rate through the turbine, with the net addition of water to the primary system; for

  10. OPTIMIZATION OF SESAME SEEDS OIL EXTRACTION OPERATING CONDITIONS USING THE RESPONSE SURFACE DESIGN METHODOLOGY

    Directory of Open Access Journals (Sweden)

    HAITHAM OSMAN

    2016-12-01

    Full Text Available This paper applies Response Surface Design (RSD to model the experimental data obtained from the extraction of sesame seeds oil using n-hexane, chloroform and acetone as solvents under different operating conditions. The results obtained revealed that n-hexane outperformed the extraction obtained using chloroform and acetone. The developed model predicted that n-hexane with a rotational speed of 547 rpm and a contact time between the solvent and seeds of 19.46 hours with solvent: seeds ratio of 4.93, yields the optimum oil extracted of 37.03 %, outperforming chloroform and acetone models that gave prediction for 4.75 and 4.21 respectively. While the maximum predictions yield for chloroform is 6.73 %, under the operating conditions of 602 rpm, and 24 hours contact time, with a ratio of solvent: seeds of 1.74. On the other hand the acetone maximum prediction is only 4.37 %, with operational conditions of 467 rpm, and 6.00 hours contact time, with a ratio of solvent: seeds of 1. It is has been found that the maximum oil extraction yield obtained from the chloroform (6.73 % and Acetone (4.37 % is much lower than that predicted by n-hexane 37.03 %.

  11. Large-eddy simulations of a mixed-flow pump at off-design conditions

    Science.gov (United States)

    Posa, Antonio; Lippolis, Antonio; Balaras, Elias

    2014-11-01

    Reduced flow-rates in turbopumps produce significant unsteady phenomena, characterized by separation and back-flow. In this study an LES approach coupled with an immersed-boundary methodology is utilized to investigate the changes in the flow physics, when compared to nominal flow-rates. The present methodology has been already validated for the design case through comparison with PIV experiments in the literature. It will be shown that for a reduced flow rate (40% of the design one) separation phenomena are generated on the suction side of the rotor blades and on the pressure side of the stator ones. Significant spanwise non-uniformity is produced in the diffuser channels, with a displacement of the flow towards the hub side and back-flow on the shroud side. The values of turbulent kinetic energy are increased by an order of magnitude at off-design conditions and the main source of turbulence is not anymore the flow from the suction side and the trailing edge of the rotor blades: most turbulence is generated now at the leading edge of the diffuser blades. The increased interaction between rotating and stationary parts implies also a stronger dependence of the flow features on the relative position between impeller and diffuser blades.

  12. [Simultaneous remediation of Cr (VI) and p-NCB by nanosacle iron].

    Science.gov (United States)

    Niu, Shao-feng; Li, Chun-hui; Lou, Zhang-hua; Xu, Yue-ping

    2009-01-01

    Nanoscale Fe and Ni/Fe, which were prepared by chemical deposition, were utilized as catalyst for remediation of Cr(VI) and pNCB in contaminated water. The interactions between Cr( VI) and p-NCB in contaminated water during the simultaneous remediation process were analyzed. It is demonstrated from the experiment that p-NCB can be degradated into p-CAN by nanoscale iron, but cannot exhibit the effect of dechlorination, and that there is a competitive relationship between Cr( VI) and p-NCB in the remediation process. The nanoscale Nil Fe bimetals could be applied in simultaneous remediation of p-NCB with Cr( VI) and give rise to a good remediation efficiency, where the products are only Cr(III) and p-CAN without any intermediate products. It was found that the conditions of higher Ni(II) concentration can promote the degradation rate of p-NCB. The optimum Ni/Fe ratio is 1:50. Whereas, the higher concentrations of Cr(VI) and p-NCB will lead to the lower degradation rate. Under the condition that concentration of Cr (VI) was 20 mg/L, the corresponding maximum dechlorination of p-NCB was 43.0%; under the condition that concentration of p-NCB was 40 mg/L, the corresponding maximum removal efficiency of Cr(VI) was 71.4%.

  13. Nitrate Enhanced Microbial Cr(VI) Reduction-Final Report

    Energy Technology Data Exchange (ETDEWEB)

    John F. Stolz

    2011-06-15

    donors are possible. Although the version of the Phylochip used for monitoring the microbial community at the Hanford site did not include S. barnesii it did have probes for detecting other Sulfurospirillum species (e.g., S. multivorans, S. halorespirans). For D. desulfuricans, again, redox active proteins such as dissimilatory nitrite reductase and dissimilary sulfite reductase are effectively oxidized by Cr(VI) thus inhibiting their reductive potential. More physiological and biochemical data are needed before a possible strategy can be designed and assessed.

  14. Har vi brug for hovedregning?

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye

    2015-01-01

    Hvor ofte har vi brug for at regne noget i hoved? Har de fleste af os ikke altid et elektronisk hjælpemiddel ved hånden enten som en lille lommeregner eller telefonen? Selvom det umiddelbart kan synes unødvendigt at træne hovedregning, viser det sig, at netop træning af hovedregning støtter...... udvikling af hurtige regnestrategier, hvorfor det faktisk er en god ide at investere tid og energi i at træne netop dette....

  15. Design, development and test of the gearbox condition monitoring system using sound signal processing

    Directory of Open Access Journals (Sweden)

    M Zamani

    2016-09-01

    Full Text Available Introduction One of the ways used for minimizing the cost of maintenance and repairs of rotating industrial equipment is condition monitoring using acoustic analysis. One of the most important problems which always have been under consideration in industrial equipment application is confidence possibility. Each dynamic, electrical, hydraulic or thermal system has certain characteristics which show the normal condition of the machine during function. Any changes of the characteristics can be a signal of a problem in the machine. The aim of condition monitoring is system condition determination using measurements of the signals of characteristics and using this information for system impairment prognostication. There are a lot of ways for condition monitoring of different systems, but sound analysis is accepted and used extensively as a method for condition investigation of rotating machines. The aim of this research is the design and construction of considered gearbox and using of obtaining data in frequency and time spectrum in order to analyze the sound and diagnosis. Materials and Methods This research was conducted at the department of mechanical biosystem workshop at Aboureihan College at Tehran University in February 15th.2015. In this research, in order to investigate the trend of diagnosis and gearbox condition, a system was designed and then constructed. The sound of correct and damaged gearbox was investigated by audiometer and stored in computer for data analysis. Sound measurement was done in three pinions speed of 749, 1050 and 1496 rpm and for correct gearboxes, damage of the fracture of a tooth and a tooth wear. Gearbox design and construction: In order to conduct the research, a gearbox with simple gearwheels was designed according to current needs. Then mentioned gearbox and its accessories were modeled in CATIA V5-R20 software and then the system was constructed. Gearbox is a machine that is used for mechanical power transition

  16. Design of a leaching test framework for coal fly ash accounting for environmental conditions.

    Science.gov (United States)

    Zandi, Mohammad; Russell, Nigel V

    2007-08-01

    Fly ash from coal combustion contains trace elements which, on disposal or utilisation, may leach out, and therefore be a potential environmental hazard. Environmental conditions have a great impact on the mobility of fly ash constituents as well as the physical and chemical properties of the fly ash. Existing standard leaching methods have been shown to be inadequate by not representing possible disposal or utilisation scenarios. These tests are often criticised on the grounds that the results estimated are not reliable as they are not able to be extrapolated to the application scenario. In order to simulate leaching behaviour of fly ash in different environmental conditions and to reduce deviation between measurements in the fields and the laboratories, it is vital to study sensitivity of the fly ash constituents of interest to major factors controlling leachability. pH, liquid-to-solid ratio, leaching time, leachant type and redox potential are parameters affecting stability of elements in the fly ash. Sensitivity of trace elements to pH and liquid to solid ratio (as two major overriding factors) has been examined. Elements have been classified on the basis of their leaching behaviour under different conditions. Results from this study have been used to identify leaching mechanisms. Also the fly ash has been examined under different standard batch leaching tests in order to evaluate and to compare these tests. A Leaching Test Framework has been devised for assessing the stability of trace elements from fly ashes in different environments. This Framework assists in designing more realistic batch leaching tests appropriate to field conditions and can support the development of regulations and protocols for the management and disposal of coal combustion by-products or other solid wastes of environmental concern.

  17. Aesthetic and energy consequences of air conditioning systems in building design integration

    Directory of Open Access Journals (Sweden)

    Pucar Mila

    2009-01-01

    Full Text Available Buildings are among the top of energy consumers. It is estimated that over 50% of the overall produced energy is consumed in buildings, mainly on heating and cooling. Application of air conditioning systems saw an important expansion in the past decade. These systems are used, not only for cooling but for heating, or supplemental heating, as well (as heat pumps. While there is virtually no alternative to their usage as cooling systems, heating applications should be reconsidered in a more subtle manner to maintain the principles of energy efficiency. Mass consumption of air conditioners has as an effect a significant rise in consumption of energy, mainly during the summer. Aesthetic consequences are another important problem. Since the placement of these appliances is not regulated by law, and left to the citizens they are commonly self-initiated and misaligned which undermines aesthetic values. Additional problem is placement of air conditioning systems on protected objects (religious institutions, object under protection which undermines not only aesthetic, but historical value as well. On the other hand, many new buildings represent a positive example, since this problem is adhered from the very start of conceptual design, and these appliances are covered with adequate architectural solutions. This paper will try to cover positive and negative examples of Serbia, Montenegro, and some other Balkan and Western Europe's countries. It will also give recommendations in solving the negative energy and aesthetic consequences of these problems. Non-controlled application of air conditioning systems is becoming a health problem. Large differences between the interior and exterior temperature leads to an array of health problems registered by many medical reports. Improper maintenance of air conditioning systems could lead to bacterial propagation which could seriously damage health.

  18. Hydrological conditions of the Pietraszki water reservoir designed for the River Sufraganiec (Kielce

    Directory of Open Access Journals (Sweden)

    Ciupa Tadeusz

    2015-12-01

    Full Text Available The Pietraszki water reservoir is designed for the lower part of the River Sufraganiec catchment (61.43 sq km, in the area of Kielce. In those conditions water volume is designed to be about 1.4 hm3, and the reservoir’s maximum depth, 4.2 m. The hydrological characteristics of the ungauged catchment of the River Sufraganiec are based upon the results of stationary field observations held in the cross-section located in the same place as the designed dam head. In the present analysis GIS techniques were also used, based on data obtained from the city’s Spatial Information System and WIOŚ in Kielce. Based on the Digital Elevation Model done with Airborne Laser Scanning, the reservoir area has been designated and its bathymetric and volume curves calculated. The mean annual values of specific runoff (8.8 l s-1 km-2, runoff coefficient (39%, runoff volume (17.2 hm3, specific discharge and the filling time have been determined. The analysis also took into account the annual cycle characteristics including minimum in-stream flow calculated with the use of a number of methods. The performed analysis shows that the River Sufraganiec water resources are enough for the fast filling of the Pietraszki reservoir (depending on the season - from 22 to 114 days, even when applying the most restrictive criteria in minimum in-stream flow calculations. The ecological quality of the River Sufraganiec water in 2014 did show any significant environmental threats. The analysis shows that the quantity and quality of the River Sufraganiec water is enough for the proper functioning of the planned reservoir.

  19. The role of iron chelators and oxygen in the reduced nicotinamide adenine dinucleotide phosphate-cytochrome P450 oxidoreductase-dependent chromium(VI) reduction.

    Science.gov (United States)

    Mikalsen, A; Capellmann, M; Alexander, J

    1995-03-01

    Chromium(VI) reduction was studied in a system composed of reduced nicotinamide adenine dinucleotide phosphate-cytochrome P450 oxidoreductase (NADPH-P450 reductase) and different iron chelators and iron sources. In an aerobic phosphate buffer containing iron(II), chromium(VI) was not reduced by the Fe2+ probably because of spontaneous autoxidation of Fe2+, but freshly made Fe2+, added directly to a CrVI-containing buffer, reduced CrVI. Under anaerobic conditions, iron(II) reduced chromium(VI) stoichiometrically. A systemic containing ethylenediaminetetraacetic acid (EDTA)-Fe3+, NADPH-P450 reductase and NADPH effectively reduced chromium(VI) anaerobically. Under aerobic conditions this reaction was inhibited by about 45%. Adenosine diphosphate (ADP)-Fe3+, which is a poor acceptor of electrons from NADPH-P450 reductase, reduced chromium(VI) only marginally, Mannitol slightly increased the aerobic CrVI reduction. Addition of superoxide dismutase and catalase, which both regenerate some O2, led to inhibition of CrVI reduction. Ferritin, NADPH-P450 reductase and the iron chelators, EDTA and citrate, reduced CrVI, indicating mobilization of Fe2+ from ferritin. Low levels of EDTA (55 mumol l-1) and citrate (100 mumol l-1) in contrast to high levels (5 mmol l-1) did not increase CrVI reduction in microsomes. Using 4-(2-hydroxyethyl)-1-piperazineethane sulfonic acid buffer instead of phosphate buffer, the CrVI-reducing activity was increased.

  20. Microclimate design methods for energy-saving houses on various site conditions in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Kyeong

    2008-07-09

    A small area can have several different microclimates depending on how much sunlight, shade or wind are exposed on the area. Microclimate can be influenced by inclined terrain, surfaces, and 3-dimensionally geometry such as combinations of architectural elements and annex buildings. This study investigates microclimate modification for energy-saving using design elements of Korean traditional and passive house. Microclimate analysis method in this study enables to predict temporal and spatial variances in the building geometry. A combination of passive solar heating, cold wind blocking, indoor air circulation, natural ventilation cooling and shading etc, seasonally help to form a comfort condition with less energy consumption. The passive heating and cooling controls with microclimate modification are efficient to accomplish the energy efficiency in the building. This work includes the microclimate modifications of the high-performance designs, microclimate energy-saving methods, Passive House design methods, and common physical bases in energy simulation methods. For hot and humid summer in Korea, ventilation is beneficial for convective or evaporative cooling. The air flow through a building geometry is generated by differences in air temperature and pressure. The layout of surrounding buildings acts as barriers and diverts the flow into narrower. The resulted patterns of airflow are affected more by building geometry and orientation than by air speed. A novel simulation method combining multi-zone and CFD energy simulations is used to analyze energy-saving aspects in passive and microclimate design elements. EnergyPlus is a multi-zone energy simulation tool that uses a parameterization to simplify the energy-saving problem for each zone. However, the model is not appropriate to handle variations in the building geometry since it estimates only the average value for each volume. On the contrary, CFD method with subdivided grid units is more suitable to estimate

  1. Design and validation of an MR-conditional robot for transcranial focused ultrasound surgery in infants.

    Science.gov (United States)

    Price, Karl D; Sin, Vivian W; Mougenot, Charles; Pichardo, Samuel; Looi, Thomas; Waspe, Adam C; Drake, James M

    2016-09-01

    Current treatment of intraventricular hemorrhage (IVH) involves cerebral shunt placement or an invasive brain surgery. Magnetic resonance-guided focused ultrasound (MRgFUS) applied to the brains of pediatric patients presents an opportunity to treat IVH in a noninvasive manner, termed "incision-less surgery." Current clinical and research focused ultrasound systems lack the capability to perform neonatal transcranial surgeries due to either range of motion or dexterity requirements. A novel robotic system is proposed to position a focused ultrasound transducer accurately above the head of a neonatal patient inside an MRI machine to deliver the therapy. A clinical Philips Sonalleve MRgFUS system was expanded to perform transcranial treatment. A five degree-of-freedom MR-conditional robot was designed and manufactured using MR compatible materials. The robot electronics and control were integrated into existing Philips electronics and software interfaces. The user commands the position of the robot with a graphical user interface, and is presented with real-time MR imaging of the patient throughout the surgery. The robot is validated through a series of experiments that characterize accuracy, signal-to-noise ratio degeneration of an MR image as a result of the robot, MR imaging artifacts generated by the robot, and the robot's ability to operate in a representative surgical environment inside an MR machine. Experimental results show the robot responds reliably within an MR environment, has achieved 0.59 ± 0.25 mm accuracy, does not produce severe MR-imaging artifacts, has a workspace providing sufficient coverage of a neonatal brain, and can manipulate a 5 kg payload. A full system demonstration shows these characteristics apply in an application environment. This paper presents a comprehensive look at the process of designing and validating a new robot from concept to implementation for use in an MR environment. An MR conditional robot has been designed and

  2. Applied Orthogonal Experiment Design for the Optimum Microwave-Assisted Extraction Conditions of Polysaccharides from Rhodiolae Radix

    OpenAIRE

    Li, Fenglin; Xiao, Furen; Gong, Jingli; Yu, Tian

    2013-01-01

    An experiment on polysaccharides from Rhodiolae Radix (PRR) extraction was carried out using microwave-assisted extraction (MAE) method with an objective to establishing the optimum MAE conditions of PRR. Single factor experiments were performed to determine the appropriate range of extraction conditions, and the optimum conditions were obtained using orthogonal experiment design. The results showed that the optimum MAE conditions of PRR were as follows: solid-liquid ratio of 1:45 g/mL, irrad...

  3. Voltage controller design for air conditioning; Diseno de controlador de voltaje para aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Andrade, R; Lopez Villalobos, J.J; Valderrama Chairez, J; Ramirez, R.L. [Instituto Tecnologico de Nuevo Leon, Guadalupe, Nuevo Leon (Mexico)]. E-mails: roxana_garciaandrade@yahoo.com; xe2n@yahoo.com.mx; jose.valderrama@ieee.org

    2013-03-15

    This paper discusses the design of a voltage controller for an air conditioning system in order to generate additional power in activation or startup of the system, for which as a first stage is presented the modeling power generation of electric current through alternative means, such as solar energy. The results of this study will be the basis for development of the physical prototype of this system controller. [Spanish] El presente trabajo trata sobre el diseno de un controlador de voltaje para un sistema de aire acondicionado con el fin de generar energia adicional en la activacion o arranque de dicho sistema, para lo cual como primer fase se presenta el modelado de la generacion de corriente electrica mediante medios alternos, como lo es la energia solar. Los resultados de este trabajo seran la base para desarrollo del prototipo fisico de este sistema controlador.

  4. Thermal design of a modern, air-conditioned, single-floor, solar-powered desert house

    KAUST Repository

    Serag-Eldin, M. A.

    2011-12-01

    The paper presents a thermal analysis of a single-floor, solar-powered desert house. The house is air-conditioned and provides all modern comforts and facilities. Electrical power, which drives the entire energy system, is generated by roof-mounted photovoltaic modules. The modules are fixed on special cradles which fold at night to expose the roof to the night sky, thereby enhancing night-time cooling, which is substantial in the desert environment. A detailed dynamic heat transfer analysis is conducted for the building envelope, coupled with a solar radiation model. Application to a typical Middle-Eastern desert site reveals that indeed such a design is feasible with present-day technology; and should be even more attractive with future advances in technology. © 2011 Copyright Taylor and Francis Group, LLC.

  5. Wind tunnel testing of the DeepWind demonstrator in design and tilted operating conditions

    DEFF Research Database (Denmark)

    Battistia, L.; Benini, E.; Brighenti, A.

    2016-01-01

    The DeepWind Project aims at investigating the feasibility of a new floating vertical-axis wind turbine (VAWT) concept, whose purpose is to exploit wind resources at deep-water offshore sites. The results of an extensive experimental campaign on the DeepWind reduced scale demonstrator are here...... was installed on a high precision test bench, whose axis was suitable to be inclined up to 15° with respect to the design (i.e. upright) operating condition. The experiments were performed at the large scale, high speed wind tunnel of the Politecnico di Milano (Italy), using a “free jet” (open channel...... presented for different wind speeds and rotor angular velocities, including also skewed flow operation due to a tilted rotor arrangement. To accomplish this, after being instrumented to measure aerodynamic power and thrust (both in streamwise and transversal directions), a troposkien three-bladed rotor...

  6. Soty-Segment: Robust Color Patch Design to Lighting Condition Variation

    Science.gov (United States)

    Choi, Seung-Hwan; Han, Seungbeom; Kim, Jong-Hwan

    Significant developments have been seen over the last few years in the robot soccer domain. Considerable improvements have been made in the areas of robot control, strategy generation, vision processing, etc. In particular, in the vision area, there have been many researches aimed at decreasing processing time. However, many other issues remain in the development of ideal vision system. Despite MiroSot being a well established competition, development of a vision system is still considered as a difficult task. In global vision systems, the development of insensitive system to lighting condition variation is an important issue. This paper proposes a novel color patch design which possesses some advantages from the vision processing viewpoint. It is insensitive to lighting variation, greatly reducing vision setting time as well as providing improved recognition. The effectiveness of the proposed Soty-Segment color patch is demonstrated through real experiments.

  7. Chemistry of the Colloidal Group II-VI Nanocrystal Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Haitao [Univ. of California, Berkeley, CA (United States)

    2007-05-17

    In the last two decades, the field of nanoscience andnanotechnology has witnessed tremendous advancement in the synthesis andapplication of group II-VI colloidal nanocrystals. The synthesis based onhigh temperature decomposition of organometallic precursors has becomeone of the most successful methods of making group II-VI colloidalnanocrystals. This methodis first demonstrated by Bawendi and coworkersin 1993 to prepare cadmium chalcogenide colloidal quantum dots and laterextended by others to prepare other group II-VI quantum dots as well asanisotropic shaped colloidal nanocrystals, such as nanorod and tetrapod.This dissertation focuses on the chemistry of this type of nanocrystalsynthesis. The synthesis of group II-VI nanocrystals was studied bycharacterizing the molecular structures of the precursors and productsand following their time evolution in the synthesis. Based on theseresults, a mechanism was proposed to account for the 2 reaction betweenthe precursors that presumably produces monomer for the growth ofnanocrystals. Theoretical study based on density functional theorycalculations revealed the detailed free energy landscape of the precursordecomposition and monomerformation pathway. Based on the proposedreaction mechanism, a new synthetic method was designed that uses wateras a novel reagent to control the diameter and the aspect ratio of CdSeand CdS nanorods.

  8. Data summary report for fission product release test VI-5

    Energy Technology Data Exchange (ETDEWEB)

    Osborne, M.F.; Lorenz, R.A.; Travis, J.R.; Webster, C.S.; Collins, J.L. (Oak Ridge National Lab., TN (United States))

    1991-10-01

    Test VI-5, the fifth in a series of high-temperature fission product release tests in a vertical test apparatus, was conducted in a flowing mixture of hydrogen and helium. The test specimen was a 15.2-cm-long section of a fuel rod from the BR3 reactor in Belgium which had been irradiated to a burnup of {approximately}42 MWd/kg. Using a hot cell-mounted test apparatus, the fuel rod was heated in an induction furnace under simulated LWR accident conditions to two test temperatures, 2000 K for 20 min and then 2700 K for an additional 20 min. The released fission products were collected in three sequentially operated collection trains on components designed to measure fission product transport characteristics and facilitate sampling and analysis. The results from this test were compared with those obtained in previous tests in this series and with the CORSOR-M and ORNL diffusion release models for fission product release. 21 refs., 19 figs., 12 tabs.

  9. Experimentally designed optimized conditions for catalytic performance of nanostructured RuO2 in Biginelli reaction

    Directory of Open Access Journals (Sweden)

    F. Soleimani

    2015-10-01

    Full Text Available Nanostructured RuO2 powders were synthesized via a hydrothermal method at 180 °C for 12 h using 1 and 2 M NaOH aqueous solutions. The structure of the obtained nanomaterials was investigated by powder X-ray diffraction (PXRD technique. The morphology the obtained materials were studied by field emission scanning electron microscope (FESEM. The technique showed that with changing the reaction rout, the homogeneity of the size and morphology of the synthesized nanomaterials were changed. It was found that the morphology of the obtained materials were spherical particles using 2 M NaOH aqueous solution. Catalytic performance of the synthesized nanomaterials was investigated in Biginelli reactions for the one-pot synthesis of 3,4-dihydropyrimidin-2(1H-ones (DHPMs using Benzaldehyde derivatives, urea and ethylacetoacetate as raw materials. Experimental design method was used to obtain optimized reaction conditions. It was found that the optimized conditions were 0.028 g of catalyst, 110 °C reaction temperature and 66 min reaction time.

  10. Impact of climatic conditions on the design of a water treatment plant

    Science.gov (United States)

    Arregoitia, C.; Mesa, M. P.

    2012-04-01

    The abundance or scarcity of resources causes enormous problems for populations and societies. They mark the direction of the development that a society will take. Water imbalances, may distort optimal environmental and socioeconomic conditions of the food production. Water scarcity may limit food production and supply, putting pressure on food prices and increasing countries' dependence on food imports. Rising demand for food caused by growing populations and shifting diets, production shortfall in some countries, increased costs for key agricultural inputs and meat supply (driven in turn by energy costs), bioenergy-related incentives in some countries and possible financial speculation have all contributed to the steep rises in food prices. According to United Nations Over the past century world water withdrawals increased almost twice as fast as population growth and an increasing number of regions are chronically water short. Climate change has been defined as a change in the statistical properties of the climate system when considered over long periods of time, regardless of cause. Different factors can shape the climate forces or mechanisms and impact the food production system such as the cattle production field. This paper considers the step by step design and implementation of a water treatment plant of a community cattle farm located in Jadacaquiva under changing climatic conditions. The byproducts of the cattle, as well as the community can also have an impact depending on the decisions taken for the plant. Keywords: water, climate change, treatment plant, food scarcity

  11. Six-fold Coordinated Carbon Dioxide VI

    Energy Technology Data Exchange (ETDEWEB)

    Iota, V; Yoo, C; Klepeis, J; Jenei, Z

    2006-03-01

    Under standard conditions, carbon dioxide (CO{sub 2}) is a simple molecular gas and an important atmospheric constituent while silicon dioxide (SiO{sub 2}) is a covalent solid, and represents one of the fundamental minerals of the planet. The remarkable dissimilarity between these two group IV oxides is diminished at higher pressures and temperatures as CO{sub 2} transforms to a series of solid phases, from simple molecular to a fully covalent extended-solid V, structurally analogous to SiO{sub 2} tridymite. Here, we present the discovery of a new extended-solid phase of carbon dioxide (CO{sub 2}): a six-fold coordinated stishovite-like phase VI, obtained by isothermal compression of associated CO{sub 2}-II above 50GPa at 530-650K. Together with the previously reported CO{sub 2}-V and a-carbonia, this new extended phase indicates a fundamental similarity between CO{sub 2}--a prototypical molecular solid, and SiO{sub 2}--one of Earth's fundamental building blocks. The phase diagram suggests a limited stability domain for molecular CO{sub 2}-I, and proposes that the conversion to extended-network solids above 40-50 GPa occurs via intermediate phases II, III, and IV. The crystal structure of phase VI suggests strong disorder along the caxis in stishovite-like P4{sub 2}/mnm, with carbon atoms manifesting an average six-fold coordination within the framework of sp{sup 3} hybridization.

  12. Biogenic sulfides for sequestration of Cr (VI, COD and sulfate from synthetic wastewater

    Directory of Open Access Journals (Sweden)

    Anamika Verma

    2015-04-01

    Full Text Available The aim of this work is to explore the possibility of using mixed culture of mesophilic sulfate-reducing bacteria (SRB for retrieval of toxic and carcinogenic Cr (VI from synthetic solution. In order to treat Cr (VI containing wastewater effectively, SRB culture was adapted to 50 mg/L Cr (VI and maintained through repeated sub-culturing to enhance the growth and activity of SRB. Batch biosorption experiments were carried out in glass serum vials by cultured SRB, accomplishing the removal of 82.1% Cr (VI, 76.9% sulfate, 85.7% COD under the following optimized conditions: pH 7, hydraulic retention time (HRT 7 days, temperature 37 °C and initial Cr (VI concentration of 50 mg/L. Further sorption experiments were conducted on synthetic wastewater under optimal operational conditions and resulted in 89.2% Cr (VI, 81.9% COD and 95.3% sulfate reduction from simulated wastewater. The results of this work contributed to a better understanding of metal uptake by biogenic sulfides and would be beneficial in the development of potential biosorbents that possess high capacities for Cr (VI uptake from aqueous environments.

  13. Vi tror ikke noget, vi undersøger det

    DEFF Research Database (Denmark)

    Hansen, Gitte Riis; Winther Johannsen, Inger

    2017-01-01

    I diskussionerne om, hvad der kan betegnes som god viden i forhold til udvikling af pædagogisk ud-vikling og kvalitet, er yderpunkterne kridtet op. Begreber som ”evidensbaseret” og ”datainformeret” synes at udfordre det pædagogiske felts egen forståelse af faglighed og pædagogisk kvalitet. I proj...... tager afsæt i det konkrete projekt og samarbejdet med døgntilbuddene. Vi viser, at arbejdet med datainformeret metode på denne måde ikke er en udradering af pædagogisk faglighed knyttet til fagprofessionel dømmekraft – snarere tværtimod...

  14. Chromium (VI) biosorption and removal of chemical oxygen demand by Spirulina platensis from wastewater-supplemented culture medium.

    Science.gov (United States)

    Magro, Clinei D; Deon, Maitê C; De Rossi, Andreia; Reinehr, Christian O; Hemkemeier, Marcelo; Colla, Luciane M

    2012-01-01

    The inappropriate discharge of wastewater containing high concentrations of toxic metals is a serious threat to the environment. Given that the microalga Spirulina platensis has demonstrated a capacity for chromium VI (Cr (VI) biosorption, we assessed the ideal concentration of chromium-containing wastewater required for maximum removal of Cr (VI) and chemical oxygen demand (COD) from the environment by using this microalga. The Paracas and Leb-52 strains of S. platensis, with initial wastewater concentrations of 0%, 12.5%, 25%, and 50%, were cultured in Zarrouk medium diluted to 50% under controlled air, temperature, and lighting conditions. The cultures were maintained for 28 days, and pH, biomass growth, COD, and Cr (VI) were assessed. The wastewater concentration influenced microalgal growth, especially at high concentrations. Removal of 82.19% COD and 60.92% Cr (VI) was obtained, but the COD removal was greater than the Cr (VI) removal in both strains of S. platensis.

  15. One-step solvothermal synthesis of TiO2-reduced graphene oxide nanocomposites with enhanced visible light photoreduction of Cr(VI)

    Science.gov (United States)

    Shaikh, Aasiya; Mishra, Shailendra Prasad; Mohapatra, Priyabrata; Parida, Smrutiranjan

    2017-06-01

    Hexavalent chromium, Cr(VI), is a mutagenic and carcinogenic heavy metal environmental pollutant. Photoreduction is one of the remediation methods of the hexavalent chromium Cr(VI), which necessitates design of an efficient catalyst for visible light performance. Here, we report a one-step solvothermal synthesis of TiO2-reduced graphene oxide (TiO2- xRGO) composite catalysts using a mild reducing agent, dimethylformamide (DMF). Nanoscale TiO2 particles in the size range of 4-9 nm were formed on the reduced graphene sheets. The formation of the composite catalysts was accompanied by the appearance of a large fluorescence quenching, which indicates an efficient separation of photogenerated electrons and holes. The composites displayed excellent photoreduction of Cr(VI) in the visible light, which was found to be a function of the weight percentage of RGO in the composite. At the optimum composition of TiO2- xRGO, a maximum removal rate of 96% was recorded, which was higher than that of the pristine TiO2, which showed no appreciable catalytic activity under the same condition. The performance degraded with increasing RGO content in the composite, which can be attributed to the higher electron-hole recombination on the RGO surface. The Cr(VI) photoreduction also exhibited a pH dependence. The highest removal rate was observed in the acidic medium.

  16. BIOADSORPTION USING COMPOST: AN ALTERNATIVE FOR REMOVAL OF CHROMIUM (VI) FROM AQUEOUS SOLUTIONS

    OpenAIRE

    Claudia Vargas; Pedro F. B. Brandão,; Jesús Ágreda,; Elianna Castillo

    2012-01-01

    The removal of Cr(VI) from aqueous solutions was studied using a compost generated from carnation flowers waste. The highest percentage of removal achieved (ca. 99 %) was obtained at pH 2.0, using a 10 mg L-1 of Cr(VI) solution, a dose of 10 g L-1 of compost, and with an equilibrium time of 3 hours. Under these conditions, the kinetics and adsorption isotherm were examined varying the initial Cr(VI) concentration from 15 to 200 mg L-1. The maximum sorption capacity at equilibrium (Qm), from t...

  17. A simple Cr(VI)–S(IV)–O{sub 2} system for rapid and simultaneous reduction of Cr(VI) and oxidative degradation of organic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Yanan; Yang, Shaojie [Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, 430079 (China); Zhou, Danna, E-mail: zdncug@163.com [Faculty of Material Science and Chemistry, China University of Geosciences, Wuhan 430074 (China); Wu, Feng [Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, 430079 (China)

    2016-04-15

    Highlights: • Rapid and simultaneous reduction of Cr(VI) and degradation of organic pollutants occur. • Oxysulfur radicals generated in Cr(VI)–S(IV)–O{sub 2} system oxidize the organic pollutants. • Acidic pH facilitates the reactions from both directions of reduction and oxidation. • Degradation potential of aromatic amines depends on the substituted groups. • Cr(VI)–S(IV)–O{sub 2} system is promising for “waste control by waste”. - Abstract: Hexavalent chromium (Cr(VI)), a heavy-metal contaminant, can be easily reduced to less toxic trivalent chromium (Cr(III)) by sulfite ions (S(IV)). However, S(IV) has not drawn as much attention as the ferrous ion has. We report herein a novel Cr(VI)–S(IV)–O{sub 2} system containing sulfite ions that rapidly and simultaneously reduces Cr(VI) and oxidize organic pollutants in the presence of oxygen in aqueous solutions. This Cr(VI)–S(IV)-O{sub 2} system contains the initiator Cr(VI), the reductant S(IV), and the oxidant O{sub 2}, which produce oxysulfur radicals (mainly SO{sub 4}·{sup −} and SO{sub 5}·{sup −}) and hydroxyl radicals (OH·). The Cr(VI)/S(IV) molar ratio, pH, and oxygen content play important roles in the entire reaction system. Acidic conditions (pH 3.0) facilitated degradation of organic compounds and reduction of Cr(VI) as well. In addition, experiments of rapid degradation of several kinds of organic pollutants such as azo dye (acid orange 7, AO7), aniline, phenol, bisphenol A etc were also conducted. Preliminary results show that the removal rates of the analogs of phenols or aromatic amines in this Cr(VI)–S(IV)–O{sub 2} system have a relationship with the electronic parameters (Hammett constant, σ) of the substituted groups. Thus, the Cr(VI)–S(IV)–O{sub 2} system, provides an excellent strategy of “waste control by waste” for removing multiple industrial contaminants.

  18. EXTRACTION DU Cr(VI PAR MEMBRANE POLYMERE A INCLUSION

    Directory of Open Access Journals (Sweden)

    O KEBICHE SENHADJI

    2008-06-01

    Le pH de la solution aqueuse constituant la phase source est un paramètre clé dans l’opération de transport du Cr(VI à travers les MPIs étudiées. Un pH de 1,2 est recommandé pour la réalisation de l’extraction dans les conditions optimales déterminées.

  19. Mens vi venter på finansloven ..

    DEFF Research Database (Denmark)

    Madsen, Mogens Ove

    2011-01-01

    Vi må dog lufte en forsigtig optimisme over, at der kom signaler om opgør med detailstyring og knopskydningen af øremærket forskning.......Vi må dog lufte en forsigtig optimisme over, at der kom signaler om opgør med detailstyring og knopskydningen af øremærket forskning....

  20. Når vi taler om 68

    DEFF Research Database (Denmark)

    Jensen, Henrik; Metz, Georg

    Når vi taler om 68 er en intellektuel samtale mellem to ligeværdige gentlemen og skallesmækkere. En essayistisk dyst om porno, RAF, Pittelkow og livsfilosofi......Når vi taler om 68 er en intellektuel samtale mellem to ligeværdige gentlemen og skallesmækkere. En essayistisk dyst om porno, RAF, Pittelkow og livsfilosofi...

  1. MURALS WITH A ViBe

    National Research Council Canada - National Science Library

    Drake, Leigh

    2017-01-01

    The ViBe District in Virginia Beach is a hub for the local arts community. There is a fenced area in the ViBe District that features a whole row of murals created by professional artists, amateurs, and student groups from all over...

  2. U(VI) biosorption by bi-functionalized Pseudomonas putida @ chitosan bead: Modeling and optimization using RSM.

    Science.gov (United States)

    Sohbatzadeh, Hozhabr; Keshtkar, Ali Reza; Safdari, Jaber; Fatemi, Faezeh

    2016-08-01

    In this work, Pseudomonas putida cells immobilized into chitosan beads (PICB) were synthesized to investigate the impact of microorganism entrapment on biosorption capacity of prepared biosorbent for U(VI) biosorption from aqueous solutions. Response Surface Methodology (RSM) based on Central Composite Design (CCD) was utilized to evaluate the performance of the PICB in comparison with chitosan beads (CB) under batch mode. Performing experiments under optimal condition sets viz. pH 5, initial U(VI) concentration 500mg/L, biosorbent dosage 0.4g/L and 20wt.% bacterial cells showed that the observed biosorption capacity enhanced by 1.27 times from 398mg/g (CB) to 504mg/g (PICB) that confirmed the effectiveness of cells immobilization process. FTIR and potentiometric titration were then utilized to characterize the prepared biosorbents. While the dominant functional group in the binding process was NH3(+) (4.78meq/g) in the CB, the functional groups of NH3(+), NH2, OH, COOH (6.00meq/g) were responsible for the PICB. The equilibrium and kinetic studies revealed that the Langmuir isotherm model and the pseudo-second-order kinetic model were in better fitness with the CB and PICB experimental data. In conclusion, the present study indicated that the PICB could be a suitable biosorbent for uranium (VI) biosorption from aqueous solutions. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Box-Behnken methodology for Cr (VI) and leather dyes removal by an eco-friendly biosorbent: F. vesiculosus.

    Science.gov (United States)

    Cobas, M; Sanromán, M A; Pazos, M

    2014-05-01

    This study focused on leather industrial effluents treatment by biosorption using Fucus vesiculosus as low-cost adsorbent. These effluents are yellowish-brown color and high concentration of Cr (VI). Therefore, biosorption process was optimized using response surface methodology based on Box-Behnken design operating with a simulated leather effluent obtained by mixture of Cr (VI) solution and four leather dyes. The key variables selected were initial solution pH, biomass dosage and CaCl2 concentration in the pretreatment stage. The statistical analysis shows that pH has a negligible effect, being the biomass dosage and CaCl2 concentration the most significant variables. At optimal conditions, 98% of Cr (VI) and 88% of dyes removal can be achieved. Freundlich fitted better to the obtained equilibrium data for all studied systems than Temkin, Langmuir or D-R models. In addition, the use of the final biosorbent as support-substrate to grown of enzyme producer fungi, Pleurotus ostreatus, was also demonstrated. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Simultaneously photocatalytic treatment of hexavalent chromium (Cr(VI)) and endocrine disrupting compounds (EDCs) using rotating reactor under solar irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Youngji [Korea Institute of Energy Research, New and Renewable Energy Research Division, Hydrogen Laboratory, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Yonsei University, Department of Chemical and Biomolecular Engineering, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Joo, Hyunku [Korea Institute of Energy Research, New and Renewable Energy Research Division, Hydrogen Laboratory, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Her, Namguk [Korea Army Academy at Young-Cheon, Department of Chemistry and Environmental Science, 135-1 Changhari, Kokyungmeon, Young-cheon, Gyeongbuk 770-849 (Korea, Republic of); Yoon, Yeomin [University of South Carolina, Department of Civil and Environmental Engineering, Columbia, SC 29208 (United States); Sohn, Jinsik [Kookmin University, School of Civil and Environmental Engineering, 77 Jeongneung-ro, Seongbuk-gu, Seoul 136-702 (Korea, Republic of); Kim, Sungpyo [Korea University, Department of Environmental Engineering, Sejong 339-700 (Korea, Republic of); Yoon, Jaekyung, E-mail: jyoon@kier.re.kr [Korea Institute of Energy Research, New and Renewable Energy Research Division, Hydrogen Laboratory, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of)

    2015-05-15

    Highlights: • Self-rotating reactor including TiO{sub 2} NTs is applied under solar irradiation. • Simultaneously photocatalysis of Cr(VI) and EDCs is observed to be up to 95%. • Photocatalytic reactions of Cr(VI) and EDCs are favorable under acidic pH. • Charge interaction and hole scavenge between TiO{sub 2} and pollutants are synergy factors. - Abstract: In this study, simultaneous treatments, reduction of hexavalent chromium (Cr(VI)) and oxidation of endocrine disrupting compounds (EDCs), such as bisphenol A (BPA), 17α-ethinyl estradiol (EE2) and 17β-estradiol (E2), were investigated with a rotating photocatalytic reactor including TiO{sub 2} nanotubes formed on titanium mesh substrates under solar UV irradiation. In the laboratory tests with a rotating type I reactor, synergy effects of the simultaneous photocatalytic reduction and oxidation of inorganic (Cr(VI)) and organic (BPA) pollutants were achieved. Particularly, the concurrent photocatalytic reduction of Cr(VI) and oxidation of BPA was higher under acidic conditions. The enhanced reaction efficiency of both pollutants was attributed to a stronger charge interaction between TiO{sub 2} nanotubes (positive charge) and the anionic form of Cr(VI) (negative charge), which are prevented recombination (electron–hole pair) by the hole scavenging effect of BPA. In the extended outdoor tests with a rotating type II reactor under solar irradiation, the experiment was extended to examine the simultaneous reduction of Cr(VI) in the presence of additional EDCs, such as EE2 and E2 as well as BPA. The findings showed that synergic effect of both photocatalytic reduction and oxidation was confirmed with single-component (Cr(VI) only), two-components (Cr(VI)/BPA, Cr(VI)/EE2, and Cr(VI)/E2), and four-components (Cr(VI)/BPA/EE2/E2) under various solar irradiation conditions.

  5. Interaction of aerobic soil bacteria with plutonium(VI)

    Energy Technology Data Exchange (ETDEWEB)

    Panak, P.J. [Lawrence Berkeley National Lab., Berkeley, CA (United States). Chemical Sciences Div.; Nitsche, H. [Lawrence Berkeley National Lab., Berkeley, CA (United States). Chemical Sciences Div.; California Univ., Berkeley, CA (United States). Dept. of Chemistry

    2001-07-01

    We studied the interaction of Pu(VI) with Pseudomonas stutzeri ATCC 17588 and Bacillus sphaericus ATCC 14577, representatives of the main aerobic groups of soil bacteria present in the upper soil layers. The biosorption studies have shown that these soil bacteria accumulate high amounts of Pu(VI). The relative sorption efficiency toward Pu(VI) related to the amount of biomass used decreased with increasing biomass concentration due to increased agglomeration of the bacteria resulting in a decrease of the number of available complexing groups. Spores of Bacillus sphaericus showed a higher biosorption than the vegetative cells at low biomass concentration which decreased significantly with increasing biomass concentration. At higher biomass concentrations (> 0.7 g/L), the vegetative cells of both strains and the spores of B. sphaericus showed comparable sorption efficiencies. Investigations on the pH dependency of the biosorption and extraction studies with 0.01 M EDTA solution have shown that the biosorption of plutonium is a reversible process and the plutonium is bound by surface complexation. Optical absorption spectroscopy showed that one third of the initially present Pu(VI) was reduced to Pu(V) after 24 hours. Kinetic studies and solvent extraction to separate different oxidation states of Pu after contact with the biomass provided further information on the yield and the kinetics of the bacteria-mediated reduction. Long-term studies showed that also 16% of Pu(IV) was formed after one month. The slow kinetics of this process indicate that under our experimental conditions the Pu(IV) was not a produced by microbial reduction but seemed to be rather the result of the disproportionation of the formed Pu(V) or autoreduction of Pu(VI). (orig.)

  6. Econophys-Kolkata VI Conference

    CERN Document Server

    Chakrabarti, Bikas; Chakraborti, Anirban; Ghosh, Asim

    2013-01-01

    The primary goal of the book is to present the ideas and research findings of active researchers such as physicists, economists, mathematicians and financial engineers working in the field of “Econophysics,” who have undertaken the task of modeling and analyzing systemic risk, network dynamics and other topics. Of primary interest in these studies is the aspect of systemic risk, which has long been identified as a potential scenario in which financial institutions trigger a dangerous contagion mechanism, spreading from the financial economy to the real economy. This type of risk, long confined to the monetary market, has spread considerably in the recent past, culminating in the subprime crisis of 2008. As such, understanding and controlling systemic risk has become an extremely important societal and economic challenge. The Econophys-Kolkata VI conference proceedings are dedicated to addressing a number of key issues involved. Several leading researchers in these fields report on their recent work and al...

  7. Removal of Cr(VI) from Aqueous Environments Using Micelle-Clay Adsorption

    Science.gov (United States)

    Qurie, Mohannad; Khamis, Mustafa; Manassra, Adnan; Ayyad, Ibrahim; Nir, Shlomo; Scrano, Laura; Bufo, Sabino A.; Karaman, Rafik

    2013-01-01

    Removal of Cr(VI) from aqueous solutions under different conditions was investigated using either clay (montmorillonite) or micelle-clay complex, the last obtained by adsorbing critical micelle concentration of octadecyltrimethylammonium ions onto montmorillonite. Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI) from aqueous solutions. Langmuir adsorption isotherm fitted the experimental data giving significant results. Filtration experiments using columns filled with micelle-clay complex mixed with sand were performed to assess Cr(VI) removal efficiency under continuous flow at different pH values. The micelle-clay complex used in this study was capable of removing Cr(VI) from aqueous solutions without any prior acidification of the sample. Results demonstrated that the removal effectiveness reached nearly 100% when using optimal conditions for both batch and continuous flow techniques. PMID:24222757

  8. Removal of Cr(VI from Aqueous Environments Using Micelle-Clay Adsorption

    Directory of Open Access Journals (Sweden)

    Mohannad Qurie

    2013-01-01

    Full Text Available Removal of Cr(VI from aqueous solutions under different conditions was investigated using either clay (montmorillonite or micelle-clay complex, the last obtained by adsorbing critical micelle concentration of octadecyltrimethylammonium ions onto montmorillonite. Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI from aqueous solutions. Langmuir adsorption isotherm fitted the experimental data giving significant results. Filtration experiments using columns filled with micelle-clay complex mixed with sand were performed to assess Cr(VI removal efficiency under continuous flow at different pH values. The micelle-clay complex used in this study was capable of removing Cr(VI from aqueous solutions without any prior acidification of the sample. Results demonstrated that the removal effectiveness reached nearly 100% when using optimal conditions for both batch and continuous flow techniques.

  9. Reduction of U(VI) by Fe(II) in the presence of hydrous ferric oxide and hematite: effects of solid transformation, surface coverage, and humic acid.

    Science.gov (United States)

    Jang, Je-Hun; Dempsey, Brian A; Burgos, William D

    2008-04-01

    Fe(II) was added to U(VI)-spiked suspensions of hydrous ferric oxide (HFO) or hematite to compare the redox behaviors of uranium in the presence of two different Fe(III) (oxyhydr)oxides. Experiments were conducted with low or high initial sorption density of U(VI) and in the presence or absence of humic acid (HA). About 80% of U(VI) was reduced within 3 days for low sorbed U(VI) conditions, with either hematite or HFO. The {Fe(3+)} in the low U(VI) experiments at 3 days, based on measured Fe(II) and U(VI) and the assumed presence of amorphous UO(2(s)), was consistent with control by HFO for either initial Fe(III) (oxyhydr)oxide. After about 1 day, partial re-oxidation to U(VI) was observed in the low sorbed U(VI) experiments in the absence of HA, without equivalent increase of dissolved U(VI). No reduction of U(VI) was observed in the high sorbed U(VI) experiments; it was hypothesized that the reduction required sorption proximity of U(VI) and Fe(II). Addition of 5mg/L HA slowed the reduction with HFO and had less effect with hematite. Mössbauer spectroscopy (MBS) of (57)Fe(II)-enriched samples identified the formation of goethite, hematite, and non-stoichiometric magnetite from HFO, and the formation of HFO, hydrated hematite, and non-stoichiometric magnetite from hematite.

  10. Finite difference simulation of biological chromium (VI) reduction in ...

    African Journals Online (AJOL)

    (VI) concentration profiles inside porous aquifer media columns. The model was thereafter used to calculate Cr(VI) removal rate for a range of Cr(VI) loadings. Internal concentration profiles were modelled against data collected from ...

  11. Optimization of Design Parameters and Operating Conditions of Electrochemical Capacitors for High Energy and Power Performance

    Science.gov (United States)

    Ike, Innocent S.; Sigalas, Iakovos; Iyuke, Sunny E.

    2017-03-01

    Theoretical expressions for performance parameters of different electrochemical capacitors (ECs) have been optimized by solving them using MATLAB scripts as well as via the MATLAB R2014a optimization toolbox. The performance of the different kinds of ECs under given conditions was compared using theoretical equations and simulations of various models based on the conditions of device components, using optimal values for the coefficient associated with the battery-kind material ( K BMopt) and the constant associated with the electrolyte material ( K Eopt), as well as our symmetric electric double-layer capacitor (EDLC) experimental data. Estimation of performance parameters was possible based on values for the mass ratio of electrodes, operating potential range ratio, and specific capacitance of electrolyte. The performance of asymmetric ECs with suitable electrode mass and operating potential range ratios using aqueous or organic electrolyte at appropriate operating potential range and specific capacitance was 2.2 and 5.56 times greater, respectively, than for the symmetric EDLC and asymmetric EC using the same aqueous electrolyte, respectively. This enhancement was accompanied by reduced cell mass and volume. Also, the storable and deliverable energies of the asymmetric EC with suitable electrode mass and operating potential range ratios using the proper organic electrolyte were 12.9 times greater than those of the symmetric EDLC using aqueous electrolyte, again with reduced cell mass and volume. The storable energy, energy density, and power density of the asymmetric EDLC with suitable electrode mass and operating potential range ratios using the proper organic electrolyte were 5.56 times higher than for a similar symmetric EDLC using aqueous electrolyte, with cell mass and volume reduced by a factor of 1.77. Also, the asymmetric EDLC with the same type of electrode and suitable electrode mass ratio, working potential range ratio, and proper organic electrolyte

  12. Computational Design of Novel Compounds and Room-temperature Superconductors at High Pressure Conditions

    Science.gov (United States)

    Ma, Yanming

    Pressure, which is a fundamental thermodynamic control on materials' properties, reduces inter-atomic distances and profoundly modifies electronic orbitals and bonding patterns. High pressure has been a versatile tool for creating exotic materials that are not accessible at ambient conditions. Recently, crystal structure prediction has played a leading role in major high-pressure discoveries. Among various structure prediction methods, CALYPSO method (http://www.calypso.cn) is developed on top of swarm-intelligence algorithms by taking the advantage of swarm structures smart learning. Application of CALYPSO into prediction of high-pressure structures has generated a number of exciting discoveries. Examples point to the predicted chemical reactions of Fe/Ni-Xe and Au-Li at high pressures with the formation of unusual compounds Fe3/Ni3Xe and AuLi4/Li5, respectively. Motivated by our theory, the Fe3/Ni3Xe compounds were recently experimentally synthesized, providing a possible solution on ``missing Xe paradox'' towards to Xe storage inside Earth core. Here, Au loses its chemical identity, and acts as a 6p element by achieving high negative oxidation state (>=-2). Our prediction of high-Tc superconductivity on highly compressed H2S initiated the recent experimental observation of record high 200 K superconductivity in H3S. Perspective towards to the design of room-T superconductors in compressed H-rich materials will be presented, including design of high Tc (>100 K) superconductor of TeH4, the highest H-content superconductor in chalcogen hydrides.

  13. Conditions of contract for construction for building and engineering works designed by the employer : general conditions : guidance for the preparation of particular conditions forms of letter of tender, contract agreement and dispute adjudication agreement

    CERN Document Server

    1999-01-01

    Conditions of Contract for Construction, which are recommended for building or engineering works designed by the Employer or by his representative, the Engineer. Under the usual arrangements for this type of contract, the Contractor constructs the works in accordance with a design provided by the Employer. However, the works may include some elements of Contractor-designed civil, mechanical, electrical and/or construction works.

  14. The effect of process conditions on the alpha-amylolytic hydrolysis of amylopectin potato starch : an experimental design approach

    NARCIS (Netherlands)

    Marchal, L.M.; Jonkers, J.; Franke, G.T.; Goooijer, de C.D.; Tramper, J.

    1999-01-01

    The hydrolysis of amylopectin potato starch with Bacillus licheniformis α-amylase (Maxamyl) was studied under industrially relevant conditions (i.e. high dry-weight concentrations). The following ranges of process conditions were chosen and investigated by means of an experimental design: pH [5.6-

  15. Improved signal conditioning circuit design for ionic polymer transducers as sensors

    Science.gov (United States)

    Akle, Barbar J.; Zahi, Nakad

    2009-03-01

    Several researchers are actively studying Ionomeric polymer transducers (IPT) as a large strain low voltage Electro- Active Polymer (EAP) actuator. EAPs are devices that do not contain any moving parts leading to a potential large life time. Furthermore, they are light weight and flexible. IPT have the ability to generate bending strains on the order 5% when +2V potential is applied across its thickness. As sensors however, IPTs are proven to be superior compared to any other EAP material when a charge amplifier is used as a signal conditioner. Furthermore, researchers has developed miniature sensors from IPTs that could be flush mounted to a surface and measure shear stresses due to fluid flow at even low Reynolds numbers. Sensor resolution is on the order of 10 mPa enables it to be useful as a wall shear stress sensor for several aero/hydrodynamic and biomedical applications. In this paper a new signal conditioning circuit is designed with superior sensing capabilities compared to the old circuit. In the new circuit the IPT is biased with a small voltage on the order of 5mV to 25 mV. Initial experimental results demonstrated 30% enhancement in signal to noise ratio compared to the old circuit. Furthermore, this circuit enables the use of IPT polymers with larger capacitance compared to the previous circuits. Akle et al. demonstrated that the capacitance of an ionic polymer transducer is proportional to transducer performance. Ionic polymers are generally made of an ion exchange membrane, typically Nafion, coated with a flexible electrode. In this study the Direct Assembly Process (DAP) is used for the fabrication of IPT. The DAP consists of mixing a metal particulate with an ionomer solution and spraying it directly on a diluent saturated ion conducting membrane. The thickness of the electrode is controlled by altering the amount of the ionomer/metal mix sprayed on the membrane. Thicker electrodes provide IPT with a larger capacitance, and hence larger

  16. Adsorption Properties of Bentonite with In Situ Immobilized Polyaniline Towards Anionic Forms of Cr(VI, Mo(VI, W(VI, V(V

    Directory of Open Access Journals (Sweden)

    Kateryna RYABCHENKO

    2016-05-01

    Full Text Available A new composite material bentonite-PANI was synthesized by in situ immobilization of polyaniline (PANI on the surface of natural mineral bentonite. It was established as a result of the modification of bentonite a surface area and an interlayer distance of mineral decrease and particles of bentonite transformed of irregular shape with different porosity on irregularly shaped particles of smaller size. It has been found that the total Cr(VI ions extraction took place under the acid conditions (pH=1 – 2 and W(VI ions have been well adsorbed in the pH range from 1 to 8 by the composite bentonite-PANI unlike the initial mineral. Whereas adsorption of oxo anions of V(V and Mo(VI made up some 50%. It is proved that the in situ immobilization of bentonite by polyaniline leads to increasing the value of adsorption capacity towards the investigated ions compared with the initial mineral. It was established that the adsorption properties of the synthesized composite with respect to the studied oxo ions were worse than the adsorption properties of composite vermiculite-PANI, similar to the composite Sokyryntsyy clinoptilolite-PANI and better than composites of polyaniline with Podilskyy saponite and Karelian shungite.DOI: http://dx.doi.org/10.5755/j01.ms.22.2.6976

  17. Optimization of cardiovascular stent against restenosis: factorial design-based statistical analysis of polymer coating conditions.

    Directory of Open Access Journals (Sweden)

    Gayathri Acharya

    Full Text Available The objective of this study was to optimize the physicodynamic conditions of polymeric system as a coating substrate for drug eluting stents against restenosis. As Nitric Oxide (NO has multifunctional activities, such as regulating blood flow and pressure, and influencing thrombus formation, a continuous and spatiotemporal delivery of NO loaded in the polymer based nanoparticles could be a viable option to reduce and prevent restenosis. To identify the most suitable carrier for S-Nitrosoglutathione (GSNO, a NO prodrug, stents were coated with various polymers, such as poly (lactic-co-glycolic acid (PLGA, polyethylene glycol (PEG and polycaprolactone (PCL, using solvent evaporation technique. Full factorial design was used to evaluate the effects of the formulation variables in polymer-based stent coatings on the GSNO release rate and weight loss rate. The least square regression model was used for data analysis in the optimization process. The polymer-coated stents were further assessed with Differential scanning calorimetry (DSC, Fourier transform infrared spectroscopy analysis (FTIR, Scanning electron microscopy (SEM images and platelet adhesion studies. Stents coated with PCL matrix displayed more sustained and controlled drug release profiles than those coated with PLGA and PEG. Stents coated with PCL matrix showed the least platelet adhesion rate. Subsequently, stents coated with PCL matrix were subjected to the further optimization processes for improvement of surface morphology and enhancement of the drug release duration. The results of this study demonstrated that PCL matrix containing GSNO is a promising system for stent surface coating against restenosis.

  18. Preliminary experiment design of graphite dust emission measurement under accident conditions for HTGR

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Wei, E-mail: pengwei@tsinghua.edu.cn [Institute of Nuclear and New Energy Technology of Tsinghua University, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 100084 (China); Chen, Tao; Sun, Qi; Wang, Jie [Institute of Nuclear and New Energy Technology of Tsinghua University, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 100084 (China); Yu, Suyuan, E-mail: suyuan@tsinghua.edu.cn [Center for Combustion Energy, The Key Laboratory for Thermal Science and Power Engineering, Ministry of Education, Tsinghua University, Beijing 100084 (China)

    2017-05-15

    Highlights: • A theoretical analysis is used to predict the total graphite dust release for an AVR LOCA. • Similarity criteria must be satisfied between the experiment and the actual HTGR system. • Model experiments should be conducted to predict the graphite dust resuspension rate. - Abstract: The graphite dust movement behavior is significant for the safety analyses of high-temperature gas cooled reactor (HTGR). The graphite dust release for accident conditions is an important source term for HTGR safety analyses. Depressurization release tests are not practical in HTGR because of a radioactivity release to the environment. Thus, a theoretical analysis and similarity principles were used to design a group of modeling experiments. Modeling experiments for fan start-up and depressurization process and actual experiments of helium circulator start-up in an HTGR were used to predict the rate of graphite dust resuspension and the graphite dust concentration, which can be used to predict the graphite dust release during accidents. The modeling experiments are easy to realize and the helium circulator start-up test does not harm the reactor system or the environment, so this experiment program is easily achieved. The revised Rock’n’Roll model was then used to calculate the AVR reactor release. The calculation results indicate that the total graphite dust releases during a LOCA will be about 0.65 g in AVR.

  19. Optimization of Cardiovascular Stent against Restenosis: Factorial Design-Based Statistical Analysis of Polymer Coating Conditions

    Science.gov (United States)

    Acharya, Gayathri

    2012-01-01

    The objective of this study was to optimize the physicodynamic conditions of polymeric system as a coating substrate for drug eluting stents against restenosis. As Nitric Oxide (NO) has multifunctional activities, such as regulating blood flow and pressure, and influencing thrombus formation, a continuous and spatiotemporal delivery of NO loaded in the polymer based nanoparticles could be a viable option to reduce and prevent restenosis. To identify the most suitable carrier for S-Nitrosoglutathione (GSNO), a NO prodrug, stents were coated with various polymers, such as poly (lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG) and polycaprolactone (PCL), using solvent evaporation technique. Full factorial design was used to evaluate the effects of the formulation variables in polymer-based stent coatings on the GSNO release rate and weight loss rate. The least square regression model was used for data analysis in the optimization process. The polymer-coated stents were further assessed with Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy analysis (FTIR), Scanning electron microscopy (SEM) images and platelet adhesion studies. Stents coated with PCL matrix displayed more sustained and controlled drug release profiles than those coated with PLGA and PEG. Stents coated with PCL matrix showed the least platelet adhesion rate. Subsequently, stents coated with PCL matrix were subjected to the further optimization processes for improvement of surface morphology and enhancement of the drug release duration. The results of this study demonstrated that PCL matrix containing GSNO is a promising system for stent surface coating against restenosis. PMID:22937015

  20. Seismic Design Value Evaluation Based on Checking Records and Site Geological Conditions Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Tienfuan Kerh

    2013-01-01

    Full Text Available This study proposes an improved computational neural network model that uses three seismic parameters (i.e., local magnitude, epicentral distance, and epicenter depth and two geological conditions (i.e., shear wave velocity and standard penetration test value as the inputs for predicting peak ground acceleration—the key element for evaluating earthquake response. Initial comparison results show that a neural network model with three neurons in the hidden layer can achieve relatively better performance based on the evaluation index of correlation coefficient or mean square error. This study further develops a new weight-based neural network model for estimating peak ground acceleration at unchecked sites. Four locations identified to have higher estimated peak ground accelerations than that of the seismic design value in the 24 subdivision zones are investigated in Taiwan. Finally, this study develops a new equation for the relationship of horizontal peak ground acceleration and focal distance by the curve fitting method. This equation represents seismic characteristics in Taiwan region more reliably and reasonably. The results of this study provide an insight into this type of nonlinear problem, and the proposed method may be applicable to other areas of interest around the world.

  1. Performance of Metal and Polymeric O-Ring Seals during Beyond-Design-Basis Thermal Conditions.

    Science.gov (United States)

    Yang, Jiann C; Hnetkovsky, Edward; Rinehart, Doris; Fernandez, Marco; Gonzalez, Felix; Borowsky, Joseph

    2017-04-01

    This paper summarizes the small scale thermal exposure test results of the performance of metallic and polymeric O-ring seals typically used in radioactive material transportation packages. Five different O-ring materials were evaluated: Inconel/silver, ethylene-propylene diene monomer (EPDM), polytetrafluoroethylene (PTFE), silicone, butyl, and Viton. The overall objective of this study is to provide test data and insights to the performance of these Oring seals when exposed to beyond-design-basis temperature conditions due to a severe fire. Tests were conducted using a small-scale stainless steel pressure vessel pressurized with helium to 2 bar or 5 bar at room temperature. The vessel was then heated in an electric furnace to temperatures up to 900 °C for a pre-determined period (typically 8 h to 9 h). The pressure drop technique was used to determine if leakage occurred during thermal exposure. Out of a total of 46 tests performed, leakage (loss of vessel pressure) was detected in 13 tests.

  2. Enabling electrochemical reduction of nitrogen to ammonia at ambient conditions through rational catalyst design.

    Science.gov (United States)

    Abghoui, Younes; Garden, Anna L; Hlynsson, Valtýr Freyr; Björgvinsdóttir, Snædís; Ólafsdóttir, Hrefna; Skúlason, Egill

    2015-02-21

    Commercial design of a sustainable route for on-site production of ammonia represents a potential economic and environmental breakthrough. In an analogous process to the naturally occurring enzymatic mechanism, synthesis of ammonia could be achieved in an electrochemical cell, in which electricity would be used to reduce atmospheric nitrogen and water into ammonia at ambient conditions. To date, such a process has not been realized due to slow kinetics and low faradaic efficiencies. Although progress has been made in this regard, at present there exists no device that can produce ammonia efficiently from air and water at room temperature and ambient pressure. In this work, a scheme is presented in which electronic structure calculations are used to screen for catalysts that are stable, active and selective towards N2 electro-reduction to ammonia, while at the same time suppressing the competing H2 evolution reaction. The scheme is applied to transition metal nitride catalysts. The most promising candidates are the (100) facets of the rocksalt structures of VN and ZrN, which show promise of producing ammonia in high yield at low onset potentials.

  3. Sorption of uranium(VI) using oxime-grafted ordered mesoporous carbon CMK-5

    Energy Technology Data Exchange (ETDEWEB)

    Tian Gan; Geng Junxia; Jin Yongdong; Wang Chunli; Li Shuqiong; Chen Zhen; Wang Hang; Zhao Yongsheng [College of Chemistry, Sichuan University, Chengdu 610064 (China); Li Shoujian, E-mail: sjli000616@scu.edu.cn [College of Chemistry, Sichuan University, Chengdu 610064 (China)

    2011-06-15

    A new sorbent for uranium(VI) has been developed by functionalizing ordered mesoporous carbon CMK-5 with 4-acetophenone oxime via thermally initiated diazotization. The sorption of U(VI) ions onto the functionalized CMK-5 (Oxime-CMK-5) was investigated as a function of sorbent dosage, pH value, contact time, ionic strength and temperature using batch sorption techniques. The results showed that U(VI) sorption onto Oxime-CMK-5 was strongly dependent on pH, but to a lesser extent, on ionic strength. Kinetic studies revealed that the sorption process achieved equilibrium within 30 min and followed a pseudo-first-order rate equation. The isothermal data correlated with the Langmuir model better than the Freundlich model. Thermodynamic data indicated the spontaneous and endothermic nature of the process. Under current experimental conditions, a maximum U(VI) sorption capacity was found to be 65.18 mg/g. Quantitative recovery of uranium was achieved by desorbing the U(VI)-loaded Oxime-CMK-5 with 1.0 mol/L HCl and no significant decrease in U(VI) sorption capability of Oxime-CMK-5 was observed after five consecutive sorption-desorption cycles. The sorption study performed in a simulated nuclear industry effluent demonstrated that the new sorbent showed a desirable selectivity for U(VI) ions over a range of competing metal ions.

  4. Photocatalytic reduction of Cr(VI) by citric and oxalic acids over biogenetic jarosite.

    Science.gov (United States)

    Xu, Zhihui; Bai, Shuangyou; Liang, Jianru; Zhou, Lixiang; Lan, Yeqing

    2013-05-01

    In this study, a series of bath experiments were carried out to investigate the photoreduction of Cr(VI) by small molecular weight organic acids (SOAs) over jarosite, a mineral found in acid mine drainage (AMD). The results demonstrated that jarosite or SOAs alone was unable to effectively transform Cr(VI) to Cr(III) even if exposed to an illumination of mimic solar light. However, an addition of jarosite significantly enhanced the reduction of Cr(VI) by SOAs under the same condition. The photocatalytic reduction of Cr(VI) was strongly influenced by pH, the initial concentrations and the structures of SOAs. Of the tested two SOAs, the reaction rates of photocatalytic reduction of Cr(VI) were in the order of oxalic acid>citric acid. The reaction obeyed to zero-order kinetics with respect to Cr(VI) with excess SOAs. A possible mechanism for photoreduction of Cr(VI) by SOAs over jarosite was proposed. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Turning up the heat on aircraft structures. [design and analysis for high-temperature conditions

    Science.gov (United States)

    Dobyns, Alan; Saff, Charles; Johns, Robert

    1992-01-01

    An overview is presented of the current effort in design and development of aircraft structures to achieve the lowest cost for best performance. Enhancements in this area are focused on integrated design, improved design analysis tools, low-cost fabrication techniques, and more sophisticated test methods. 3D CAD/CAM data are becoming the method through which design, manufacturing, and engineering communicate.

  6. Emissions of chromium (VI) from arc welding.

    Science.gov (United States)

    Heung, William; Yun, Myoung-Jin; Chang, Daniel P Y; Green, Peter G; Halm, Chris

    2007-02-01

    The presence of Cr in the +6 oxidation state (Cr[VI]) is still observed in ambient air samples in California despite steps taken to reduce emissions from plating operations. One known source of emission of Cr(VI) is welding, especially with high Cr-content materials, such as stainless steels. An experimental effort was undertaken to expand and update Cr(VI) emission factors by conducting tests on four types of arc-welding operations: gas-metal arc welding (GMAW), shielded metal arc welding (SMAW), fluxcore arc welding, and pulsed GMAW. Standard American Welding Society hood results were compared with a total enclosure method that permitted isokinetic sampling for particle size-cut measurement, as well as total collection of the aerosol. The fraction of Cr(VI) emitted per unit mass of Cr electrode consumed was determined. Consistent with AP-42 data, initial results indicate that a significant fraction of the total Cr in the aerosol is in the +6 oxidation state. The fraction of Cr(VI) and total aerosol mass produced by the different arc welding methods varies with the type of welding process used. Self-shielded electrodes that do not use a shield gas, for example, SMAW, produce greater amounts of Cr(VI) per unit mass of electrode consumed. The formation of Cr(VI) from standard electrode wires used for welding mild steel was below the method detection limit after eliminating an artifact in the analytical method used.

  7. Anaerobic bio-removal of uranium (VI) and chromium (VI): Comparison of microbial community structure

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Monica [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB - Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande 1749-016 Lisboa (Portugal); Santos, Erika [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, Maria Clara, E-mail: mcorada@ualg.pt [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2010-04-15

    Several microbial communities, obtained from uranium contaminated and non-contaminated samples, were investigated for their ability to remove uranium (VI) and the cultures capable for this removal were further assessed on their efficiency for chromium (VI) removal. The highest efficiency for removal of both metals was observed on a consortium from a non-contaminated soil collected in Monchique thermal place, which was capable to remove 91% of 22 mg L{sup -1} U(VI) and 99% of 13 mg L{sup -1} Cr(VI). This study revealed that uranium (VI) removing communities have also ability to remove chromium (VI), but when uranium (VI) was replaced by chromium (VI) several differences in the structure of all bacterial communities were observed. TGGE and phylogenetic analysis of 16S rRNA gene showed that the uranium (VI) removing bacterial consortia are mainly composed by members of Rhodocyclaceae family and Clostridium genus. On the other hand, bacteria from Enterobacteriaceae family were detected in the community with ability for chromium (VI) removal. The existence of members of Enterobacteriaceae and Rhodocyclaceae families never reported as chromium or uranium removing bacteria, respectively, is also a relevant finding, encouraging the exploitation of microorganisms with new abilities that can be useful for bioremediation.

  8. Implementation of MP_Lite for the VI Architecture

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Weiyi [Iowa State Univ., Ames, IA (United States)

    2001-01-01

    MP_Lite is a light weight message-passing library designed to deliver the maximum performance to applications in a portable and user friendly manner. The Virtual Interface (VI) architecture is a user-level communication protocol that bypasses the operating system to provide much better performance than traditional network architectures. By combining the high efficiency of MP_Lite and high performance of the VI architecture, they are able to implement a high performance message-passing library that has much lower latency and better throughput. The design and implementation of MP_Lite for M-VIA, which is a modular implementation of the VI architecture on Linux, is discussed in this thesis. By using the eager protocol for sending short messages, MP_Lite M-VIA has much lower latency on both Fast Ethernet and Gigabit Ethernet. The handshake protocol and RDMA mechanism provides double the throughput that MPICH can deliver for long messages. MP_Lite M-VIA also has the ability to channel-bonding multiple network interface cards to increase the potential bandwidth between nodes. Using multiple Fast Ethernet cards can double or even triple the maximum throughput without increasing the cost of a PC cluster greatly.

  9. Expedited Programs for Serious Conditions: An Update on Breakthrough Therapy Designation.

    Science.gov (United States)

    Kwok, Martin; Foster, Theresa; Steinberg, Michael

    2015-09-01

    Our aim was to describe the regulatory pathways made available by the US Food and Drug Administration (FDA) to expedite the drug development and approval process, with a focus on the benefits and limitations of the Breakthrough Therapy Designation (BTD) pathway. Published materials consisting of journal articles, press releases, government documents, and news articles from pharmaceutical publishers were identified through online databases (ie, Medline and Scopus), the FDA website, and Internet search engines (eg, Google). To encourage pharmaceutical innovation and increase the number of products being approved each year, the FDA has introduced 4 expedited regulatory pathways to accelerate the drug development and approval process. The most recent program, enacted in July 2012, was BTD that is given to drugs that treat a serious or life-threatening disease or condition; and preliminary clinical evidence suggests the potential for these drugs to provide a substantial improvement over the current standard of care. The primary basis for the creation of BTD is to provide patients with serious conditions with earlier access to FDA-approved medications. In 2014, 22% of the new molecular entities approved within the Center for Drug Evaluation and Research had BTD status, as opposed to only 11% in 2013, which indicates both the popularity and success of this expedited pathway. Additionally, the creation of BTD has produced a more collaborative working relationship between the pharmaceutical industry and the FDA because both parties have a vested interest in the drug's success. Some of the more notable concerns surrounding these approved breakthrough therapies have been the abbreviated tolerability and efficacy evidence available from accelerated clinical development programs, ensuring the manufacturing aspects keep pace with these accelerated clinical programs, and finally, managing the strain on resources for both the pharmaceutical companies and the FDA. BTD has already

  10. Learning the vi and Vim Editor

    CERN Document Server

    Robbins, Arnold; Hannah, Elbert

    2008-01-01

    There's nothing that hard-core Unix and Linux users are more fanatical about than their text editor. Editors are the subject of adoration and worship, or of scorn and ridicule, depending upon whether the topic of discussion is your editor or someone else's. vi has been the standard editor for close to 30 years. Popular on Unix and Linux, it has a growing following on Windows systems, too. Most experienced system administrators cite vi as their tool of choice. And since 1986, this book has been the guide for vi. However, Unix systems are not what they were 30 years ago, and neither is this

  11. Mucopolissacaridose tipo VI: relato de caso

    OpenAIRE

    Lais Orosco Bialon Santana; Carolina Ando Matsuno; Marta Wey Vieira

    2014-01-01

    Introdução: As mucopolissacaridoses são erros inatos do metabolismo de depósito lisossomal subclassificadas segundo a enzima deficiente. A arilsulfatase B (ARSB), responsável por degradar os glicosaminoglicanos (GAGs), que atuam no tecido conjuntivo, é deficiente na mucopolissacaridose tipo VI (MP VI). A MP VI tem clínica variável, sem anormalidades ao nascimento, evidenciando-se progressivamente ao acúmulo de GAGs. O diagnóstico se faz pela redução da atividade da ARSB ou da mutação genética...

  12. Photocatalytic reduction of Cr(VI) by small molecular weight organic acids over schwertmannite.

    Science.gov (United States)

    Jiang, Danjun; Li, Ying; Wu, Yong; Zhou, Pei; Lan, Yeqing; Zhou, Lixiang

    2012-10-01

    In this study, a series of bath experiments was carried out to investigate the photoreduction of Cr(VI) by small molecular weight organic acids (SOAs) over schwertmannite, a mineral found in acid mine drainage (AMD). The results demonstrated that schwertmannite or SOAs alone was unable to effectively transform Cr(VI) to Cr(III) even if exposed to an illumination of mimic solar light. However, an addition of schwertmannite significantly enhanced the reduction of Cr(VI) by SOAs under the same condition. For example, 100μM Cr(VI) was almost completely removed within 50min in the presence of both schwertmannite (0.6gL(-1)) and oxalic acid (300μM) at pH 3.0. The photocatalytic reduction of Cr(VI) was strongly influenced by pH, the initial concentrations and the structures of SOAs. Of the tested three SOAs, the reaction rates of photocatalytic reduction of Cr(VI) were in the order of oxalic acid>citric acid>tartaric acid. The reaction obeyed to zero-order kinetics with respect to Cr(VI) with excess SOAs. A possible mechanism for photoreduction of Cr(VI) by SOAs over schwertmannite was proposed. Fe(III) on the surface of schwertmannite was dissolved by SOAs, and then Fe(III)-SOA complexes with high photochemical activity formed. Further, Fe(II) together with organic acid radicals, CO(2)(-) and O(2)(-), was generated through a metal-ligand-charge-transfer pathway (MLCT), leading to a rapid reduction of Cr(VI). Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Bromide oxidation by ferrate(VI): The formation of active bromine and bromate.

    Science.gov (United States)

    Jiang, Yanjun; Goodwill, Joseph E; Tobiason, John E; Reckhow, David A

    2016-06-01

    Ferrate (VI) (abbreviated as Fe(VI)) has long been considered as a green oxidant that does not produce any known hazardous byproducts. However, this work shows that Fe(VI) can slowly oxidize bromide forming active bromine (HOBr/OBr(-)) and bromate, and in natural waters total organic bromine (TOBr) can also be detected. Results showed that the highest levels of active bromine and bromate were formed at lower pHs and in the absence of phosphate. Hydrogen peroxide, which forms from the reaction of Fe(VI) and water, plays an essential role in suppressing bromate formation by reducing active bromine back to bromide. Fe(VI) decomposition products (assumed to be particulate phase Fe(III)) can catalyze the decomposition of hydrogen peroxide by Fe(VI). Phosphate had a substantial inhibiting effect on the formation of active bromine, but less so on bromate formation. The presence of the raw water matrix in natural water suppressed bromate formation. For a natural water spiked with 0.1 mg/L of bromide, the bromate and TOBr concentrations after Fe(VI) oxidation were below 3.0 and 15 μg/L, respectively. No consistent trend regarding the effect of pH or buffer ions on TOBr formation was observed due to the competition between Fe(VI), hydrogen peroxide, and natural organic matter (NOM) for reaction with active bromine. Under environmentally relevant conditions, the formation of bromate and TOBr would not be a problem for Fe(VI) application as their concentration levels are quite low. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Ex-situ bioremediation of U(VI from contaminated mine water using Acidithiobacillus ferrooxidans strains

    Directory of Open Access Journals (Sweden)

    Maria eRomero-Gonzalez

    2016-05-01

    Full Text Available The ex-situ bioremoval of U(VI from contaminated water using Acidithiobacillus ferrooxidans strain 8455 and 13538 was studied under a range of pH and uranium concentrations. The effect of pH on the growth of bacteria was evaluated across the range 1.5 – 4.5 pH units. The respiration rate of At. ferrooxidans at different U(VI concentrations was quantified as a measure of the rate of metabolic activity over time using an oxygen electrode. The biosorption process was quantified using a uranyl nitrate solution, U-spiked growth media and U-contaminated mine water. The results showed that both strains of At. ferrooxidans are able to remove U(VI from solution at pH 2.5 – 4.5, exhibiting a buffering capacity at pH 3.5. The respiration rate of the micro-organism was affected at U(VI concentration of 30 mg L-1. The kinetics of the sorption fitted a pseudo-first order equation, and depended on the concentration of U(VI. The KD obtained from the biosorption experiments indicated that strain 8455 is more efficient for the removal of U(VI. A bioreactor designed to treat a solution of 100 mg U(VI L-1 removed at least 50% of the U(VI in water. The study demonstrated that At. ferrooxidans can be used for the ex-situ bioremediation of U(VI contaminated mine water.

  15. Adequacy of different experimental designs for eucalyptus spacing trials in Portuguese environmental conditions

    Science.gov (United States)

    Paula Soares; Margarida Tome

    2000-01-01

    In Portugal, several eucalyptus spacing trials cover a relatively broad range of experimental designs: trials with a non-randomized block design with plots of different size and number of trees per plot; trials based on a non-systematic design in which spacings were randomized resulting in a factorial arrangement with plots of different size and shape and equal number...

  16. The new geographic information system in ETVA VI.PE.

    Science.gov (United States)

    Xagoraris, Zafiris; Soulis, George

    2016-08-01

    ETVA VI.PE. S.A. is a member of the Piraeus Bank Group of Companies and its activities include designing, developing, exploiting and managing Industrial Areas throughout Greece. Inside ETVA VI.PE.'s thirty-one Industrial Parks there are currently 2,500 manufacturing companies established, with 40,000 employees and € 2.5 billion of invested funds. In each one of the industrial areas ETVA VI.PE guarantees the companies industrial lots of land (sites) with propitious building codes and complete infrastructure networks of water supply, sewerage, paved roads, power supply, communications, cleansing services, etc. The development of Geographical Information System for ETVA VI.PE.'s Industrial Parks started at the beginning of 1992 and consists of three subsystems: Cadastre, that manages the information for the land acquisition of Industrial Areas; Street Layout - Sites, that manages the sites sold to manufacturing companies; Networks, that manages the infrastructure networks (roads, water supply, sewerage etc). The mapping of each Industrial Park is made incorporating state-of-the-art photogrammetric, cartographic and surveying methods and techniques. Passing through the phases of initial design (hybrid GIS) and system upgrade (integrated Gis solution with spatial database), the system is currently operating on a new upgrade (integrated gIS solution with spatial database) that includes redesigning and merging the system's database schemas, along with the creation of central security policies, and the development of a new web GIS application for advanced data entry, highly customisable and standard reports, and dynamic interactive maps. The new GIS bring the company to advanced levels of productivity and introduce the new era for decision making and business management.

  17. Response surface methodological approach for the optimization of adsorption process in the removal of Cr(VI) ions by Cu2(OH)2CO3 nanoparticles

    Science.gov (United States)

    Srivastava, Varsha; Sharma, Y. C.; Sillanpää, Mika

    2015-01-01

    Cu2(OH)2CO3 nanoparticles were synthesized and characterized by XRD, TEM, SEM and ATR-FTIR. SEM suggested the porous nature of nanoparticles. BET surface area of nanoparticles was measured to be 87 m2 g-1. Cu2(OH)2CO3 nanoparticles were used as adsorbent for the removal of Cr(VI) ions from aqueous solutions and wastewater of the printing press. The central composite design (CCD) of the response surface methodology was employed to optimize important adsorption parameters viz. initial Cr(VI) concentration, pH and dose. Analysis of variance (ANOVA) of the quadratic model suggested that experimental data were excellently fitted to the quadratic model. Optimum conditions for approximately 99% removal of Cr(VI) from synthetic wastewater were determined to be pH 6.5, initial concentration of 550 mg/L, adsorbent dose 0.69 g. The kinetic data for Cr(VI) adsorption were best fitted to the pseudo second order model. The Langmuir adsorption capacity of the adsorbent was determined as 87.72 mg/g. Thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic. Desorption study confirms its reusability up to four adsorption-desorption cycles. Cu2(OH)2CO3 nanoparticles also showed efficient removal in presence of anions like SO42-, PO43-, NO32- and Cl-. Findings of the present study suggest that Cu2(OH)2CO3 is a suitable adsorbent material for the removal of Cr(VI) from aqueous solutions and wastewater.

  18. Reasoning in Design: Idea Generation Condition Effects on Reasoning Processes and Evaluation of Ideas

    DEFF Research Database (Denmark)

    Cramer-Petersen, Claus Lundgaard; Ahmed-Kristensen, Saeema

    2015-01-01

    Reasoning is at the core of design activity and thinking. Thus, understanding and explaining reasoning in design is fundamental to understand and support design practice. This paper investigates reasoning in design and its relationship to varying foci at the stage of idea generation and subsequent...... performance of ideas developed. Understanding reasoning in design and its relationship to the performance of ideas generated is important to understand design activity, which can be used to develop tools or methods that can improve the effectiveness of design teams. Protocol analyses were conducted...... to investigate idea generation sessions of two industry cases. Reasoning was found to appear in sequences of alternating reasoning types where the initiating reasoning type was decisive. The study found that abductive reasoning led to more radical ideas, whereas deductive reasoning led to ideas being for project...

  19. AR4VI: AR as an Accessibility Tool for People with Visual Impairments

    Science.gov (United States)

    Coughlan, James M.; Miele, Joshua

    2017-01-01

    Although AR technology has been largely dominated by visual media, a number of AR tools using both visual and auditory feedback have been developed specifically to assist people with low vision or blindness – an application domain that we term Augmented Reality for Visual Impairment (AR4VI). We describe two AR4VI tools developed at Smith-Kettlewell, as well as a number of pre-existing examples. We emphasize that AR4VI is a powerful tool with the potential to remove or significantly reduce a range of accessibility barriers. Rather than being restricted to use by people with visual impairments, AR4VI is a compelling universal design approach offering benefits for mainstream applications as well. PMID:29303163

  20. Study on the DNA-protein crosslinks induced by chromium (VI) in SPC-A1

    Science.gov (United States)

    Liu, Yanqun; Ding, Jianjun; Lu, Xiongbing; You, Hao

    2018-01-01

    Objective: This study was designed to investigate the effect of chromium (VI) on DNA-protein crosslinks (DPC) of SPC-A1 cells. Methods: We exposed SPC-A1 cells were cultured in 1640 medium and treated with the SPC-A1 cells in vitro to different concentrations of Hexavalent chromium Cr(VI) for 2h, the KC1-SDS precipitation assay were used to measure the DNA-protein cross-linking effect. Results: All the different concentrations of Cr(VI) could cause the increase of DPC coefficient in SPC-A1 cells. But this effect was not significant (P>0.05) at low concentrations; while in high concentration Cr(VI) induced SPC-A1 cells could produce DNA-protein cross-linking effect significantly (PDNA-protein crosslink.

  1. AR4VI: AR as an Accessibility Tool for People with Visual Impairments.

    Science.gov (United States)

    Coughlan, James M; Miele, Joshua

    2017-10-01

    Although AR technology has been largely dominated by visual media, a number of AR tools using both visual and auditory feedback have been developed specifically to assist people with low vision or blindness - an application domain that we term Augmented Reality for Visual Impairment (AR4VI). We describe two AR4VI tools developed at Smith-Kettlewell, as well as a number of pre-existing examples. We emphasize that AR4VI is a powerful tool with the potential to remove or significantly reduce a range of accessibility barriers. Rather than being restricted to use by people with visual impairments, AR4VI is a compelling universal design approach offering benefits for mainstream applications as well.

  2. Removal of Cr(VI ions from waste water by electrocoagulation using iron electrode

    Directory of Open Access Journals (Sweden)

    Yehia A. El-Taweel

    2015-06-01

    Full Text Available The performance of electrocoagulation using iron electrodes for the treatment of aqueous solutions containing chromium hexavalent ions using fixed bed electrochemical batch reactor was studied. A new anode design consisting of hex nuts was connected together with a thin rode of iron. The helical shape in the nuts increases the anode surface area allowing high chromium removal rate within very short coagulation time. The effect of different parameters affecting the electrocoagulation process, such as initial hexavalent chromium concentration, applied current, electrolyte type [sodium chloride and sodium sulfate] concentration and initial pH of the solution was investigated. The optimum conditions for the EC process by using the present cell based on minimum initial hexavalent chromium concentration, energy consumption and operating cost were 100 mg of Cr(VI/l, 0.55 A, 1.5 g of sodium chloride/land pH of 1.

  3. Polarized emission in II–VI and perovskite colloidal quantum dots

    Science.gov (United States)

    Isarov, Maya; Tan, Liang Z.; Tilchin, Jenya; Rabouw, Freddy T.; Bodnarchuk, Maryna I.; van Dijk-Moes, Relinde J. A.; Carmi, Rotem; Barak, Yahel; Kostadinov, Alyssa; Meir, Itay; Vanmaekelbergh, Daniel; Kovalenko, Maksym V.; Rappe, Andrew M.; Lifshitz, Efrat

    2017-11-01

    The polarized emission of colloidal quantum dots from II–VI and perovskite semiconductors were investigated thoroughly, revealing information about the optical transitions in these materials and their potential use in various opto-electronic or spintronic applications. The studies included recording of the micro-photoluminescence of individual nanostructures at cryogenic temperatures, with or without the influence of an external magnetic field. The experimental conditions enabled detection of circular and/or linear polarized emission to elucidate the exciton manifolds, angular momentum of the emitting states, Landé g-factors, single exciton and bi-exciton binding energies, the excitons’ effective Bohr radii, and the unique influence of the Rashba effect. The study advances the understanding of other phenomena such as electron–hole dissociation, long diffusion lengths, and spin coherence, facilitating appropriate design of optical and spin-based devices.

  4. Adsorption of Cr(VI onto Hybrid Membrane of Carboxymethyl Chitosan and Silicon Dioxide

    Directory of Open Access Journals (Sweden)

    Yanling Deng

    2017-01-01

    Full Text Available In this study, a new adsorbent material was synthesized by using carboxymethyl chitosan and silicon dioxide. The hybrid membrane was used as an adsorbent for the removal of Cr(VI from aqueous solutions. The adsorption potential of Cr(VI by the hybrid materials was investigated by varying experimental conditions such as pH, contact time, and the dosage of the hybrid membrane. Adsorption isotherms of Cr(VI onto the hybrid membrane were studied with varying initial concentrations under optimum experiment conditions. The surface property of the hybrid membrane was characterized by SEM (scanning electron microscope and Fourier transform infrared spectrometer (FTIR. The concentrations of Cr(VI in solution are determined by ICP-AES (inductively coupled plasma atomic emission spectrometry. The present study investigates the adsorption mechanisms of Cr(VI onto the hybrid membrane. The results provide new insight, demonstrating that the modified hybrid membrane can be an efficient adsorbent for Cr(VI from the aqueous solution.

  5. ViSIT: Visitor Survey Information Tool

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — ViSIT is an interactive web tool created by USGS to visualize the data collected as part of the National Wildlife Refuge Visitor Survey. The national survey was...

  6. Uranium(VI) sorption complexes on silica in the presence of calcium and carbonate.

    Science.gov (United States)

    Saleh, Alaaeldine Sh; Lee, Jun-Yeop; Jo, Yongheum; Yun, Jong-Il

    2018-02-01

    Uranium sorption on minerals and related solids depends to a large degree on its aqueous speciation. The present work attempts to understand the U(VI) sorption behavior on silica under environmentally relevant conditions, i.e. at neutral to weakly alkaline pH and in the presence of dissolved calcium and carbonate. Under these conditions, Ca(UO2)(CO3)32- and Ca2(UO2)(CO3)3(aq) complexes emerge as the dominant aqueous U(VI) species. The U(VI) sorption affinity was measured as a function of contact time, solution pH, and humic acid. The U(VI) sorption decreased with increase of pH and was not affected by the addition of 50 mg/L humic acid. On the other hand, nitric acid was more effective than EDTA and carbonate at desorbing U(VI). Generally, the U(VI) sorbed on silica at neutral pH was less readily desorbed than that sorbed at higher pH values. Therefore, the U(VI) complex favorably sorbed on silica at the neutral pH is more strongly bound to the silica surface than that sorbed at higher pH values. Time-resolved laser fluorescence spectroscopy confirmed the results of the batch sorption experiments and revealed the presence of two surface U(VI) complexes with fluorescence lifetimes 251 ± 8 μs and 807 ± 24 μs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Applications of Ferrate(VI) to Wastewater Reclamation and Water Treatment

    Science.gov (United States)

    Kim, H.; Choi, H.; Lee, K.; Nam, J.; Kim, I.

    2010-12-01

    The estimated amount of water resources is about 63 billion cubic meters in Korea. However, due to the lack of precipitation during the dry season, natural flows are not enough for the water supply. In addition, since the lack of water affects water quality, environmental problems are occurred in natural and social systems. In this study, we investigated the application feasibility of ferrate(VI) systems to water and wastewater treatment. And we'd like to suggest an alternative solution for conservation and efficient reuse of the limited water resources. In the research area of environmental applications, a primary interest has been focused to the power of ferrate(VI) systems in the decomposition of pollutants in wastewater and industrial effluents due to its potential use as a strong, relatively non-toxic, and oxidizing agent for diverse environmental contaminants. Also ferrate(VI) has additional advantages as a very efficient coagulant and a sorbent of pollutants. We have analysed and compared several ferrate(VI) manufacturing processes, especially focused on the electro chemical methods(Fig. 1). And we have investigated the applications of the manufactured ferrate(VI) in our own laboratory and the commercial ferrate(VI) to decomposition of persistent organic pollutants in water. Under optimal conditions, the removal efficiencies of 2-chlorophenol and benzothiophene were above 90%(Fig. 2). The ferrate system(VI) is promising and can be one of the most efficient alternatives among the advanced oxidation processes(AOPs) for degradation of persistent organic pollutants, and is an innovative technology for the wastewater reclamation, water reusing systems, and water treatment systems. Fig 1. Comparison of Electro-Chemical Ferrate(VI) manufacturing Processes Fig 2. Degradation of 2-Chlorophenol and Bezothiophene by Ferrate. (Experimental Conditions : 2-CP = 3ppm, BT = 5ppm, NaClO4 = 0.05M)

  8. Derfor elsker og hader vi positiv psykologi

    DEFF Research Database (Denmark)

    Mehlsen, Camilla

    2010-01-01

    Hvorfor er positiv psykologi så populært? Er positiv psykologi ved at blive en religion? Asterisk har mødt tre fremtrædende forskere, der forklarer, hvorfor vi elsker og hader positiv psykolog.......Hvorfor er positiv psykologi så populært? Er positiv psykologi ved at blive en religion? Asterisk har mødt tre fremtrædende forskere, der forklarer, hvorfor vi elsker og hader positiv psykolog....

  9. Kan vi forebygge en kompliceret sorgreaktion?

    DEFF Research Database (Denmark)

    Nielsen, Mette Kjærgaard; Guldin, Mai-Britt

    2017-01-01

    Pårørende til alvorligt syge patienter er i en sårbar situation og risikerer selv at blive syge. Som sundhedsprofessionelle har vi mulighed for at støtte pårørende i palliative forløb, og vi vil i denne artikel beskrive mulige prædiktorer for kompliceret sorg og depression hos den pårørende efter...

  10. Hvad skal vi med Trump-satire?

    DEFF Research Database (Denmark)

    Møller, Mette

    2017-01-01

    Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til? Link: http://videnskab.dk/kultur-samfund/hvad-skal-vi-med-trump-satire...

  11. CIRCUIT-DESIGN SOLUTIONS AND INFORMATION SUPPORT OF CITY ELECTRIC NETWORKS IN THE CONDITIONS OF THE SMART GRID

    OpenAIRE

    M. I. Fursanov

    2017-01-01

    The structure, circuit-design solutions and information support of the city electric networks in the conditions of the SMART GRID have been analyzed. It is demonstrated that the new conditions of functioning of electric power engineering, increasing demands for its technological state and reliability in most countries determined the transition to a restructuring of electrical networks to be based on the SMART GRID (intelligent power networks) innovative new structure. The definitions of the S...

  12. Conditions for the Successful Implementation of Teacher Educator Design Teams for ICT Integration: A Delphi Study

    Science.gov (United States)

    Becuwe, Heleen; Roblin, Natalie Pareja; Tondeur, Jo; Thys, Jeroen; Castelein, Els; Voogt, Joke

    2017-01-01

    Teacher educators often struggle to model effective integration of technology. Several studies suggest that the involvement of teacher educators in collaborative design is effective in developing the competences necessary for integrating information and communication technology (ICT) in teaching. In a teacher educator design team (TeDT), two or…

  13. DESIGN GUIDELINES FOR GOOD HEARING CONDITIONS AND EFFECTIVE NOISE CONTROL IN SCHOOL CLASSROOMS.

    Science.gov (United States)

    KINGSBURY, H.F.; TAYLOR, D.W.

    TWO OF THE MOST IMPORTANT OPERATIVE DESIGN FACTORS GOVERNING SPEECH PERCEPTION IN CLASSROOMS HAVE BEEN EXAMINED AND GUIDELINES IN THE FORM OF GRAPHS, ETC. CONSTRUCTED THAT SHOULD BE UNDERSTANDABLE TO AND USABLE BY THOSE ASSOCIATED WITH SCHOOL PLANNING AND DESIGN. THE TWO FACTORS CONSIDERED ARE--(1) PROVISION FOR OPTIMUM REVERBERATION TIME, AND (2)…

  14. Test Equating under the NEAT Design: A Necessary Condition for Anchor Items

    Science.gov (United States)

    Raykov, Tenko

    2010-01-01

    Mroch, Suh, Kane, & Ripkey (2009); Suh, Mroch, Kane, & Ripkey (2009); and Kane, Mroch, Suh, & Ripkey (2009) provided elucidating discussions on critical properties of linear equating methods under the nonequivalent groups with anchor test (NEAT) design. In this popular equating design, two test forms are administered to different…

  15. Wanting to Learn: A Necessary Condition for the Effectiveness of Instructional Design

    Science.gov (United States)

    Gropper, George L.

    2015-01-01

    There are inevitable challenges standing in the way of the success of any approach to Instructional Design. Some are being faced up to. Some are not. Not least among them is the absence of empirically established principles undergirding Instructional Design prescriptions. The challenge it poses is to their reliability and validity. Nothing that…

  16. CONDITIONS AND ORGANIZATION OF THE TRANSITION TO BASIC TECHNOLOGIES OF A NEW TECHNOLOGICAL STRUCTURE

    Directory of Open Access Journals (Sweden)

    B. L. Bourov

    2011-01-01

    Full Text Available With due account for the coming new (VI-th world technological structure, future creation of new types of industrial production is both possible and necessary. Economic environment conditions favorable for such development are designated. In reference to Russian technological environment particulars, self-developing economic-technological microenvironment of a new quality level should be created in zones where controlled «technological chains» function. Possibilities of creation of the VI-th technological structure level basic technologies are shown for industrial and household waste processing techniques as an example.

  17. CONDITIONS AND ORGANIZATION OF THE TRANSITION TO BASIC TECHNOLOGIES OF A NEW TECHNOLOGICAL STRUCTURE

    Directory of Open Access Journals (Sweden)

    B. L. Bourov

    2012-01-01

    Full Text Available With due account for the coming new (VI-th world technological structure, future creation of new types of industrial production is both possible and necessary. Economic environment conditions favorable for such development are designated. In reference to Russian technologicalenvironment particulars, self-developing economic-technological microenvironment of a new quality level should be created in zones where controlled «technological chains» function. Possibilities of creation of the VI-th technological structure level basic technologies are shown for industrial and household waste processing techniques as an example.

  18. Design and Analysis of Financial Condition Local Government Java and Bali (2013-2014

    Directory of Open Access Journals (Sweden)

    Natrini Nur Dewi

    2017-01-01

    Full Text Available This research aims to identify financial condition of local government in Java and Bali year 2013-2014. It is due to government financial condition, according to several researchers, provides an image on the ability of a government in fulfilling their obligations whether in the form of debt or service fulfillment in timely manner. According to assessment upon financial condition, local government is able to identify how to fulfill public needs, how to utilize resources and how to proceed resources so that it can be more productive. As for the measurement method of financial condition itself, the standard method cannot be determined. Therefore, indicator used for measuring local government financial condition is Brown's (1993[2] indicator development adjusted to Indonesian government. In order to develop the indicator, this research employs qualitative method by comparing GASB No.34, SAP Government Regulation (“Peraturan Pemerintah” - PP 71 Year 2010, SAP PP 24 year 2005 and literature studies and expert validation. In order to obtain a balanced comparison, this research also employs clusters developed by Baidori (2015[1] for government in Java and Bali. Results of this research showed that among 7 analyzed clusters, there are variations of results, even though each cluster has similar socioeconomic condition to each other. This variation upon Indonesian local government financial condition is caused by regional autonomy.

  19. Adsorption Process and Mechanism of Cd(Ii and Cr(Vi Removal from Aqueous Solution by Waste Marigold Flowers

    Directory of Open Access Journals (Sweden)

    Monoj Kumar Mondal

    2015-12-01

    Full Text Available In this work, waste marigold flowers from Temple were used as adsorbent to remove cadmium (II and chromium (VI ions from aqueous solutions. Influences of initial heavy metal concentrations, contact time, adsorbent dose, temperature and initial pH on removal of cadmium (II and chromium (VI ions were studied under batch mode of operation. Both the adsorption process of cadmium (II and chromium (VI followed pseudo-second order kinetics. Adsorption isotherm parameters of cadmium (II and chromium (VI on dried marigold flower were determined using Langmuir and Freundlich models. Thermodynamic parameters depicted that the process was spontaneous and exothermic under experimental conditions. The maximum removal efficiency of cadmium (II was obtained as 83% at contact time 75 min and pH 5. The maximum removal efficiency of chromium (VI was found as 96% at contact time 105 min and pH 3. Dried marigold flower showed active reusability characteristics upto three consecutive adsorption-desorption cycles.

  20. Application of plasma electrolysis method for simultaneous phenol and Cr(VI) wastewater degradation using Na2SO4 electrolyte

    Science.gov (United States)

    Harianti, Aulia Rahmi; Saksono, Nelson

    2017-11-01

    Phenol and Cr (VI) are two types of wastewater known as dangerous and difficult to degrade. Through this study, phenol and Cr (VI) metal wastewater were degraded simultaneously using plasma electrolysis method by reactive species, •OH and H•. The variation of anode depth and position of plasma formation as independent variables correlated with yield of hydroxyl radical, percentage of phenol and Cr (VI) degradation, and specific energy. Within 30 minutes, phenol was degraded to 98.4% and Cr (VI) was degraded to 93.35% with 171.05 kJ/mmol in specific energy, and 174.53 ppm in COD. The optimum condition was obtained in anodic plasma and 1.5 cm in anode depth. The highest degradation percentage of phenol and Cr (VI) were 99.79% and 97.33% achieved during 180 minutes of plasma electrolysis process.

  1. Heating, Ventilation and Air-Conditioning Systems, Part of Indoor Air Quality Design Tools for Schools

    Science.gov (United States)

    The main purposes of a Heating, Ventilation, and Air-Conditioning system are to help maintain good indoor air quality through adequate ventilation with filtration and provide thermal comfort. HVAC systems are among the largest energy consumers in schools.

  2. Design of Controlled Processing Conditions for Drop Forgings Made of Microalloy Steel Grades for Mining Industry

    National Research Council Canada - National Science Library

    P. Skubisz; A. Żak; M. Burdek; Ł. Lisiecki; P. Micek

    2015-01-01

    .... The goal of the work is producing microstructure condition, which after controlled hot forging and direct heat treatment, involving quenching and self-tempering, are meant to provide good combination...

  3. BLAME IT ON THE WEATHER: COST AND DESIGN OF MANURE MANAGEMENT UNDER EXTREME WEATHER CONDITIONS ON NORTH CAROLINA SWINE FARMS

    OpenAIRE

    Chvosta, Jan; Zering, Kelly D.; Norwood, F. Bailey

    2004-01-01

    The majority of pig farms in North Carolina use a lagoon-sprayfield system to manage manure. Although economical, the lagoon-sprayfield system is sensitive to weather conditions. This study examines the cost of manure management under extreme weather and scrutinizes National Resource Conservation Service (NRCS) design criteria and regulations.

  4. Seismic site coefficients and acceleration design response spectra based on conditions in South Carolina : final report.

    Science.gov (United States)

    2014-11-15

    The simplified procedure in design codes for determining earthquake response spectra involves : estimating site coefficients to adjust available rock accelerations to site accelerations. Several : investigators have noted concerns with the site coeff...

  5. Studies on Cr(VI) removal from aqueous solutions by nanotitania ...

    Indian Academy of Sciences (India)

    The current study deals with Cr(VI) removal by nanotitania under fluorescent light and dark conditions. The equilibrium removal capacities, ... both the conditions, the equilibrium removal data fitted well with the Langmuir isotherm model. ... state posing serious threats to the human being. Hexavalent chromium has proved to ...

  6. Effect of thiols enrichment on Cr(VI) photo-reduction by natural organic matter (NOM).

    Science.gov (United States)

    Luo, Hong-Wei

    2016-05-01

    Photochemical redox transformation of Cr(VI)-NOM complexes substantially affects transport and speciation of less toxic Cr(III) in natural waters. However, the underlying mechanisms remain unclear. This study reported photochemical reactions of Cr(VI) with thiol-enriched NOM under acidic condition. More effective thiols enrichment in humic acid (HA) was observed than that in fulvic acid (FA), thereby resulting in a higher reduction capacity and faster rate of Cr(VI) photo-reduction. Chemical addition of sulfide to HA formed a large number of S-containing molecular formulae, which subsequently disappeared following reactions with Cr(VI) under solar irradiation. Cr(VI) photo-reduction in thiol-enriched HA consumed more S-containing formulae. Solar irradiation caused a rapid loss of the reduction capacities and thiol contents in HA and FA. All these findings can provide useful information for understanding the biogeochemical cycles of chromium and sulfur, and are also of environmental significance because they may partially account for photo-transformation of Cr(VI) when chromium enters into the aquatic environment as acidic industrial effluents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Chromium(VI) removal via reduction-sorption on bi-functional silica adsorbents.

    Science.gov (United States)

    Zaitseva, Nataliya; Zaitsev, Vladimir; Walcarius, Alain

    2013-04-15

    Organically-modified silica gels bearing mercaptopropyl and ethylenediaminetriacetate groups (SiO2-SH/ED3A) have been used for reduction and subsequent sequestration of Cr(VI) species. The uptake mechanism involves Cr(VI) reduction by thiol groups (SH) and further immobilization of the so-generated Cr(III) species via complexation to the ethylenediaminetriacetate moieties (ED3A). The most appropriate pH range (1-3) for complete Cr(VI) reduction-sorption by SiO2-SH/ED3A originates from the balance between full reduction of Cr(VI) by SH, requiring low pH values, and quantitative complexation of Cr(III) by ED3A, which is favored in less acidic media. Such bi-functional adsorbents are considerably more effective at removal of Cr(VI) than those simply modified with thiol groups alone. The whole reduction-sorption process was characterized by fast kinetics, thus permitting efficient use of the SiO2-SH/ED3A adsorbent in dynamic conditions (column experiments). Monitoring the amount of immobilized chromium species on the solid was achieved using X-ray fluorescence spectroscopy and UV-vis spectroscopy. Studying the influence of ionic strength and presence of heavy metals revealed few interference on Cr(VI) removal. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Interface control of electronic and optical properties in IV-VI and II-VI core/shell colloidal quantum dots: a review.

    Science.gov (United States)

    Jang, Youngjin; Shapiro, Arthur; Isarov, Maya; Rubin-Brusilovski, Anna; Safran, Aron; Budniak, Adam K; Horani, Faris; Dehnel, Joanna; Sashchiuk, Aldona; Lifshitz, Efrat

    2017-01-17

    Semiconductor colloidal quantum dots (CQDs) have attracted vast scientific and technological interest throughout the past three decades, due to the unique tuneability of their optoelectronic properties by variation of size and composition. However, the nanoscale size brings about a large surface-to-bulk volume ratio, where exterior surfaces have a pronounced influence on the chemical stability and on the physical properties of the semiconductor. Therefore, numerous approaches have been developed to gain efficient surface passivation, including a coverage by organic or inorganic molecular surfactants as well as the formation of core/shell heterostructures (a semiconductor core epitaxially covered by another semiconductor shell). This review focuses on special designs of core/shell heterostructures from the IV-VI and II-VI semiconductor compounds, and on synthetic approaches and characterization of the optical properties. Experimental observations revealed the formation of core/shell structures with type-I or quasi-type-II band alignment between the core and shell constituents. Theoretical calculations of the electronic band structures, which were also confirmed by experimental work, exposed surplus electronic tuning (beyond the radial diameter) with adaptation of the composition and control of the interface properties. The studies also considered strain effects that are created between two different semiconductors. It was disclosed experimentally and theoretically that the strain can be released via the formation of alloys at the core-shell interface. Overall, the core/shell and core/alloyed-shell heterostructures showed enhancement in luminescence quantum efficiency with respect to that of pure cores, extended lifetime, uniformity in size and in many cases good chemical sustainability under ambient conditions.

  9. Determination of Cr(III, Cr(VI and total chromium in atmospheric aerosol samples

    Directory of Open Access Journals (Sweden)

    Catrambone M.

    2013-04-01

    Full Text Available This study addresses the optimization and validation of an analytical method based on the ultrasound-assisted extraction of soluble Cr from atmospheric particulate matter (PM and subsequent determination of Cr(III and Cr(VI by catalytic adsorptive stripping voltammetry (CAdSV by using diethylenetriammino pentaacetic acid (DTPA as complexing agent in the presence of nitrate. We evaluated the influence of various filter materials and of extracting conditions and validated the method on both reference material and real PM10 samples. The accuracy of total extractable Cr determination was checked by parallel ICP-OES measurements. The determination of total chromium was performed by ED-XRF. Results of field campaigns carried out in two industrial areas (North Italy and Tunis and at a peri-urban site near Rome are reported. At the peri-urban site, the total Cr concentration in PM10 ranged from 2 to 5 ng/m3, with a soluble fraction of 5-13%, and Cr(VI concentration was always below the detection limits (50 pg/m3. In the industrial area of Northern Italy, total Cr concentration ranged between 6 and 11 ng/m3, the soluble fraction was about 11-28% and detectable amounts of Cr(VI were found, with a Cr(VI/Cr(III ratio ranging from 0.5 to 2.5. A further increase of Cr(VI concentration was evidenced at the industrial site of Tunis, where the total Cr concentration ranged from 6 to 26 ng/m3, with a soluble fraction accounting for about 8-44% and a Cr(VI/Cr(III ranging from 1.6 to 3.6. The results of size-segregated samples, collected in Northen Italy by a 10-stage cascade impactor, indicate a relevant fine fraction of Cr(VI, with Cr(VI/Cr(III ratios increasing with the decrease of particle size.

  10. Adsorption behavior of carboxylated cellulose nanocrystal-polyethyleneimine composite for removal of Cr(VI) ions

    Science.gov (United States)

    Liu, Chao; Jin, Ru-Na; Ouyang, Xiao-kun; Wang, Yang-Guang

    2017-06-01

    In this study, a composite adsorbent (CCN-PEI) composed of carboxylated cellulose nanocrystals (CCN) and polyethyleneimine (PEI) was prepared through an amidation reaction between the carboxyl groups of the CCN and the amine groups of the PEI. The adsorption performance of the CCN-PEI was tested by removing Cr(VI) ions from aqueous solutions. The physicochemical properties of the CCN and the Cr(VI) ion-loaded CCN-PEI were studied using scanning electron microscopy (SEM), transmission electron microscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. To investigate the adsorption kinetics of Cr(VI) ions onto this newly developed CCN-PEI, we performed experiments under different adsorption conditions, by varying the contact time, solution pH, initial Cr(VI) ion concentration, and adsorption temperature. The prepared CCN-PEI exhibited an encouraging uptake capacity of 358.42 mg × g-1. The adsorption process was fast: within the first 100 min, Cr(VI) ion adsorption onto the CCN-PEI was about 65%, and the adsorption equilibrium was reached within 250 min. Kinetics experiments indicated that the adsorption process could be described by a pseudo-second-order kinetic model. Furthermore, our adsorption equilibrium data fit the Langmuir isotherms well. The calculated thermodynamic parameters, such as the free energy change (ΔG = -2.93 kJ × mol-1), enthalpy change (ΔH = -5.69 kJ × mol-1), and entropy change (ΔS = -9.14 kJ × mol-1), indicate that the adsorption of Cr(VI) ions onto CCN-PEI was a spontaneous exothermic process. Regeneration tests indicated that CCN-PEI showed good durability and good efficiency for repeated Cr(VI) adsorptions. Based on the results obtained in this work, it can be concluded that CCN-PEI is a potentially effective adsorbent for removing Cr(VI) ions from aqueous solutions.

  11. Analytical display design for flight tasks conducted under instrument meteorological conditions

    Science.gov (United States)

    Hess, R. A.

    1977-01-01

    A relatively straightforward, nearly algorithmic procedure for deriving model-based pilot-centered display requirements is presented. A pilot model based on modern control theory serves as the backbone of the design methodology, which is specifically directed toward the synthesis of head-down, electronic cockpit display formats. Some novel applications of the optimal pilot model are discussed, including the generation of vehicle-handling-qualities levels via numerical pilot-opinion ratings. An analytical design example is offered which aids in the definition of a format for the electronic display to be used in a UH-1H helicopter in a landing-approach task involving longitudinal and lateral degrees of freedom. It is proposed that the design procedure offers a systematic means for generating candidate display formats and flight-director laws for simulator evaluation.

  12. Design and Realization of a Condition Management System for the Gateway Electrical Energy Metering Device

    Directory of Open Access Journals (Sweden)

    Chao Tang

    2013-12-01

    Full Text Available With the construction of firm and intelligent power grid in China, it is difficult for the traditional management method of electrical energy metering device to meet the prospecting requirements. Using the computer and internet techniques to realize the information and intelligentization of the electrical energy metering management has become a necessary guarantee of improving power supply ability, marketing control, and customer service. This paper introduced a kind of large and intelligent condition management system of the gateway electrical energy metering device. The key technologies and realize process were analyzed. Moreover, a detailed description of the application modules such as the GIS smart display of metering point, the condition management of metering devices and the visual monitoring of metering point was presented. The trial operation in the selected transformer substations and the power stations of Chongqing Power Electrical Corp. indicated that, the condition management system is very open, safety and efficient. According to the data exchange with the production and scheduling platform, the system improved the efficient operation of the electrical energy metering devices. Meanwhile, combined with the real-time visual monitoring, the condition management system improved the prevention ability of electricity filching, realized the unified automatic large-scale management of electrical energy metering devices.

  13. Testing facility for hydrogen storage materials designed to simulate application based conditions

    NARCIS (Netherlands)

    Westerwaal, R.J.; Nyqvist, R.G.; Haije, W.G.

    2011-01-01

    For the daily use of hydrogen storage materials, not only their intrinsic storage properties are important, but also equally important is the performance under practical conditions. Besides the techniques already available for the fundamental characterization of storage materials, there is a growing

  14. 76 FR 31454 - Special Conditions: Gulfstream Model GVI Airplane; Automatic Speed Protection for Design Dive Speed

    Science.gov (United States)

    2011-06-01

    ... flight at V C /M C , the airplane is upset so as to take up a new flight path 7.5 degrees below the.... Twenty seconds after initiating the upset, manual recovery is made at a load factor of 1.5 g (0.5... Federal Aviation Administration 14 CFR Part 25 Special Conditions: Gulfstream Model GVI Airplane...

  15. Clustering Words to Match Conditions: An Algorithm for Stimuli Selection in Factorial Designs

    Science.gov (United States)

    Guasch, Marc; Haro, Juan; Boada, Roger

    2017-01-01

    With the increasing refinement of language processing models and the new discoveries about which variables can modulate these processes, stimuli selection for experiments with a factorial design is becoming a tough task. Selecting sets of words that differ in one variable, while matching these same words into dozens of other confounding variables…

  16. Investigation of an experimental ejector refrigeration machine operating with refrigerant R245fa at design and off-design working conditions. Part 1. Theoretical analysis

    KAUST Repository

    Shestopalov, K.O.

    2015-07-01

    © 2015 Elsevier Ltd and IIR.All rights reserved. The ejector refrigeration machine (ERM) offers several advantages over other heat-driven refrigeration machine, including simplicity in design and operation, high reliability and low installation cost, which enable its wide application in the production of cooling. In this paper the theoretical analysis of ejector design and ejector refrigeration cycle performance is presented. It is shown that ERM performance characteristics depend strongly on the operating conditions, the efficiency of the ejector used, and the thermodynamic properties of the refrigerant used. A 1-D model for the prediction of the entrainment ratio ω, and an optimal design for ejectors with cylindrical and conical-cylindrical mixing chambers are presented in this paper. In order to increase ERM performance values, it is necessary first of all to improve the performance of the ejector.

  17. Virtual phantom magnetic resonance imaging (ViP MRI) on a clinical MRI platform.

    Science.gov (United States)

    Saint-Jalmes, Hervé; Bordelois, Alejandro; Gambarota, Giulio

    2018-01-01

    The purpose of this study was to implement Virtual Phantom Magnetic Resonance Imaging (ViP MRI), a technique that allows for generating reference signals in MR images using radiofrequency (RF) signals, on a clinical MR system and to test newly designed virtual phantoms. MRI experiments were conducted on a 1.5 T MRI scanner. Electromagnetic modelling of the ViP system was done using the principle of reciprocity. The ViP RF signals were generated using a compact waveform generator (dimensions of 26 cm × 18 cm × 16 cm), connected to a homebuilt 25 mm-diameter RF coil. The ViP RF signals were transmitted to the MRI scanner bore, simultaneously with the acquisition of the signal from the object of interest. Different types of MRI data acquisition (2D and 3D gradient-echo) as well as different phantoms, including the Shepp-Logan phantom, were tested. Furthermore, a uniquely designed virtual phantom - in the shape of a grid - was generated; this newly proposed phantom allows for the investigations of the vendor distortion correction field. High quality MR images of virtual phantoms were obtained. An excellent agreement was found between the experimental data and the inverse cube law, which was the expected functional dependence obtained from the electromagnetic modelling of the ViP system. Short-term time stability measurements yielded a coefficient of variation in the signal intensity over time equal to 0.23% and 0.13% for virtual and physical phantom, respectively. MR images of the virtual grid-shaped phantom were reconstructed with the vendor distortion correction; this allowed for a direct visualization of the vendor distortion correction field. Furthermore, as expected from the electromagnetic modelling of the ViP system, a very compact coil (diameter ~ cm) and very small currents (intensity ~ mA) were sufficient to generate a signal comparable to that of physical phantoms in MRI experiments. The ViP MRI technique was successfully implemented on a clinical MR

  18. Classroom acoustics design guidelines based on the optimization of speaker conditions

    DEFF Research Database (Denmark)

    Pelegrin Garcia, David; Brunskog, Jonas

    2012-01-01

    are suggested in order to optimize the vocal comfort and the vocal load experienced by speakers. Theoretical prediction models of room-averaged speaker-oriented parameters like voice support or reverberation time derived from an oral-binaural impulse response are combined with empirical models of actual voice....... These conditions, which are independent on the position of the speaker, cannot be optimum for more than 50 students. For classrooms with 10 students, the reverberation time in occupied conditions shall be between 0.5 and 0.65 s, and the volume between 60 and 170 m3. For classrooms with 40 students......, the reverberation times shall be between 0.7 and 0.75 s and the volume between 240 and 280 m3....

  19. Design of generated axial force measurement tester for tripod constant velocity joints under shudder condition

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kwang Hee; Lee, Deuk Won; Chung, Jin Ho; Lee, Chul Hee [Inha University, Incheon (Korea, Republic of); Cho, Won Oh [ChangAm LS, Asan (Korea, Republic of)

    2014-10-15

    Generated axial force (GAF) induced by internal friction in a tripod constant velocity (CV) joint causes shudder, which is related to lateral vibration in a vehicle. GAF is produced by tripod dynamics in the CV joint, and its magnitude is related to an applied torque and articulation angle. GAF provides periodic frictional force, owing to its kinematics, and causes take-off shudder that occurs when a vehicle abruptly accelerates from a stop position. Therefore, accurately estimating the GAF in a CV joint is necessary. A non-rotating type GAF measurement tester is developed to measure GAF more accurately, considering the shudder condition. Results of GAF measurements are compared with those obtained using an existing rotating-type tester. The developed tester provides linear results regardless of test conditions; thus, it can be used to estimate the magnitude of GAF and evaluate the friction performance of grease.

  20. Conditional Mean Values of Slightly Non-Gaussian processes with Application to design Wave-Loads

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    1996-01-01

    Recently, conditional mean wave kinematics have been derived for slightly non-Gaussian waves. The result includes cumulants up to third order and thus the lowest order of the non-Gaussian contribution. This is consistent with application of second order Stokes waves. Here theanalysis is extended...... to include all cumulants and can then be applied if these cumulants are known from a higher order wave theory or frommeasurements....

  1. ConCap: Designing to Empower Individual Reflection on Chronic Conditions using Mobile Apps

    OpenAIRE

    Owen, T.; Pearson, J.; Thimbleby, H. W.; Buchanan, G.

    2015-01-01

    The world is faced with a growing number of people who live with chronic medical conditions. There have been numerous digital interventions into personal management of these diseases in recent years, yet gaps remain in the HCI literature. In particular, we lack a systematic understanding of user requirements in tools that support independent management while away from external influences. This paper presents a first investigation into low-intervention support for self-management. A mobile app...

  2. Optimization of Cardiovascular Stent against Restenosis: Factorial Design-Based Statistical Analysis of Polymer Coating Conditions

    OpenAIRE

    Gayathri Acharya; Lee, Chi H.; Yugyung Lee

    2012-01-01

    The objective of this study was to optimize the physicodynamic conditions of polymeric system as a coating substrate for drug eluting stents against restenosis. As Nitric Oxide (NO) has multifunctional activities, such as regulating blood flow and pressure, and influencing thrombus formation, a continuous and spatiotemporal delivery of NO loaded in the polymer based nanoparticles could be a viable option to reduce and prevent restenosis. To identify the most suitable carrier for S-Nitrosoglut...

  3. Improve Shielding Effectiveness with Suitable Designing Apertures for Air Conditions in Antenna and EMC Laboratory

    OpenAIRE

    Kasra Pahlavan; M. R. Moniri

    2014-01-01

    This paper presents the electromagnetic interference shielding impact due to air vent holes on electronic systems chassis .In designing and building EMC labs one of the important factors is S.E (shielding effectiveness), if this parameter improves shielding performance of enclosure will be better and leakage of energy will reduce. If the vent hole size become larger much more air can come to the room and electronic instruments become cooler, button the other hand with growing of the size of t...

  4. Pedagogical conditions of designing regional portal of the development of students’ logical thinking and logical reflection

    OpenAIRE

    Elena Morozova

    2014-01-01

    The paper deals with the problem of designing the local information and educational space for the development of students’ logical thinking and logical reflection during the educational process. The successful use of regional portal in the educational process is determined by its structural basis and educational support, which determine the possibility of implementing pedagogical potential of the portal in the educational process and students’ logic thinking development.

  5. Design, implementation and evalution of a central unit for controlling climatic conditions in the greenhouse

    OpenAIRE

    Gh. Zarei; Azizi, A.

    2016-01-01

    In greenhouse culture, in addition to increasing the quantity and quality of crop production in comparison with traditional methods, the agricultural inputs are saved, too. Recently, using new methods, designs and materials, and higher automation in greenhouses, better management has become possible for enhancing yield and improving the quality of greenhouse crops. The constructed and evaluated central controller unit (CCU) is a central controller system and computerized monitoring unit for g...

  6. THE APPLICATION OF COMPOSITE MATERIALS IN MODERN AVIATION AND CONTROL OF ITS CONDITION DURING DESIGN SERVICE GOAL

    Directory of Open Access Journals (Sweden)

    A. V. Zibitsky

    2014-01-01

    Full Text Available This article has a purpose to give a brief review of usage of composite materials in the structure of modern civil aircraft. The current condition of civil aviation was analyzed, serious problems were determined and possible achievements in the future were discussed. Advantages and disadvantages of composite materials were analyzed, non-destructive methods of control were reviewed and the necessity to design new method, which allows to control the integrity of structure in real time during design service goal of the aircraft (the concept of “clever material” was shown.

  7. The roles of polycarboxylates in Cr(VI)/sulfite reaction system: Involvement of reactive oxygen species and intramolecular electron transfer

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Bo, E-mail: bjiang86upc@163.com [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, Shandong (China); School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033 (China); Wang, Xianli; Liu, Yukun [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, Shandong (China); Wang, Zhaohui [College of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China); Southern Cross GeoScience, Southern Cross University, Lismore, NSW 2480 (Australia); Zheng, Jingtang, E-mail: jtzheng03@163.com [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, Shandong (China); Wu, Mingbo, E-mail: wumb@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, Shandong (China)

    2016-03-05

    Highlights: • The formations of SO{sub 4}·{sup −} and OH·, involve in Cr(VI) reduction induced by S(IV). • Affinity of polycarboxylate to Cr(VI) accelerates Cr(VI) reduction rate. • Polycarboxylates can act as electron donors for Cr(VI) reduction retrenching S(IV). • Only oxalate can enhance the formations of SO{sub 4}·{sup −} and OH· in Cr(VI)/S(IV) system. - Abstract: In this study, the effects of polycarboxylates on both Cr(VI) reduction and S(IV) consumption in Cr(VI)/S(IV) system was investigated in acidic solution. Under aerobic condition, the productions of reactive oxygen species (ROS), i.e., SO{sub 4}·{sup −} and OH·, have been confirmed in S(IV) reducing Cr(VI) process by using electron spin resonance and fluorescence spectrum techniques, leading to the excess consumption of S(IV). However, when polycarboxylates (oxalic, citric, malic and tartaric acid) were present in Cr(VI)/S(IV) system, the affinity of polycarboxylates to CrSO{sub 6}{sup 2−} can greatly promote the reduction of Cr(VI) via expanding the coordination of Cr(VI) species from tetrahedron to hexahedron. Besides, as alternatives to S(IV), these polycarboxylates can also act as electron donors for Cr(VI) reduction via intramolecular electron transfer reaction, which is dependent on the energies of the highest occupied molecular orbital of these polycarboxylates. Notably, the variant electron donating capacity of these polycarboxylates resulted in different yield of ROS and therefore the oxidation efficiencies of other pollutants, e.g., rhodamine B and As(III). Generally, this study does not only shed light on the mechanism of S(IV) reducing Cr(VI) process mediated by polycarboxylates, but also provides an escalated, cost-effective and green strategy for the remediation of Cr(VI) using sulfite as a reductant.

  8. Vi overser hjertepatienter med ondt i livet

    DEFF Research Database (Denmark)

    Ørsted-Rasmussen, Morten; Pedersen, Susanne S.; Zwisler, Ann Dorthe Olsen

    2017-01-01

    Sundhedsvæsenet har ved en målrettet indsats sikret markant øget overlevelse efter blodprop i hjertet. Men vi risikerer at skylle det hele ud med badevandet, hvis der ikke bliver taget hånd om de psykiske følger i den kroniske fase af sygdommen......Sundhedsvæsenet har ved en målrettet indsats sikret markant øget overlevelse efter blodprop i hjertet. Men vi risikerer at skylle det hele ud med badevandet, hvis der ikke bliver taget hånd om de psykiske følger i den kroniske fase af sygdommen...

  9. Investigation of the removal of chromium (VI by Nanocomposites Chitosan-tragacanth solution from aqueous solution

    Directory of Open Access Journals (Sweden)

    Adel Almasi Nahnaji

    2016-03-01

    Full Text Available Background: The aim of this study was to investigate the removal of chromium (VI by Nanocomposites Chitosan-tragacanth solution from aqueous solution. Methods: In this study, chitosan-tragacanth nanocomposites were synthesized and analyzed by electron microscopy (SEM, (TEM and Fourier transform spectroscopy (FT-IR for the size and shape of the surface. The nano-composite of chitosan-tragacanth, for the adsorption of chromium (VI in aqueous solution was used as adsorbent. Results: The optimum conditions with multiple experiments to enhance the absorption were evaluated. The highest absorption of Cr (VI was occurred in the adsorbent dosage of 0.2 g, 8 ppm concentration of chromium ions, the pH=6 and also retention time of 50 min; in 298 ˚K temperature. After determining optimal conditions of adsorption, isotherms equations and study and thermodynamic parameters were applied. Adsorption process of chromium (VI on nano-composite chitosan - Tragacanth was conformed with Temkin isotherm. Conclusion: The thermodynamic parameters such as standard Gibbs free energy changes, changes in enthalpy and entropy changes in the standard showed that the adsorption process of Cr (VI is spontaneous and heating, and kinetics studies of models Lagergren, Ho , Alovich and intraparticle is used, the results show that the adsorption kinetics follows the pseudo-second order.

  10. Designing of Competitive Logistics Network for Liquefied Petroleum Gas in Conditions of Imperfect Competition

    Directory of Open Access Journals (Sweden)

    Boris Aržek

    2007-07-01

    Full Text Available The existing network for liquefied gas in the Republic ofCroatia is characterized by numerous weaknesses, led by lackof investment into LPG branch that has been going on foryears, i. e. outdated equipment and apparatuses, insufficientstorage space, outdated vehicles. The existing LPG logisticsnetwork has the following drawbacks: LPG market withoutcompetition, outdated legislative that imposes restrictions onimporters, lack of marketing know-how, insufficient investmentsfunding ( .. . Since foreign investors have been showingincreased interest in entering the Croatian LPG market, itseemed appropriate to investigate and elaborate decisive factorsand effects of constructing a new competitive logistics networkin conditions of imperfect competition.

  11. A new method for separation and determination of Cr(III) and Cr(VI) in water samples by high-performance liquid chromatography based on anion exchange stationary phase of ionic liquid modified silica.

    Science.gov (United States)

    Sadeghi, Susan; Moghaddam, Ali Zeraatkar

    2015-12-01

    In this work, N-methylimidazolium-chloride ionic liquid functionalized silica was prepared and used as an anion-exchange stationary phase for separation of chromium species by high-performance liquid chromatography (HPLC) with UV detection at 200 nm. The Cr(VI) as HCr2O7(-) and chelated Cr(III) with potassium hydrogen phthalate (PHP) as Cr(PHP)2 (-) was retained on the prepared column and separated using a mobile phase composed of 5% methanol in 25 mM phosphate buffer at pH 6.5. Several variables affecting the chelation/separation steps were modeled by response surface methodology (RSM) using Box-Behnken (BBD) design. The significance of the independent variables and their interactions were tested by the analysis of variances (ANOVA) with 95% confidence limit. Under the optimized conditions, the Cr(III) and Cr(VI) anionic species were well separated with a single peak for each Cr species at retention times of 2.3 and 4.3 min, respectively. The relationship between the peak area and concentration was linear in the range of 0.025-30 for Cr(III) and 0.5-20 mg L(-1) for Cr(VI) with detection limits of 0.010 and 0.210 mg L(-1) for Cr(III) and Cr(VI), respectively. The proposed method was validated by simultaneous separation and determination of the Cr species in tap and underground water samples without impose to any pretreatment.

  12. Flow-through Column Experiments and Modeling of Microbially Mediated Cr(VI) Reduction at Hanford 100H

    Science.gov (United States)

    Yang, L.; Molins, S.; Beller, H. R.; Brodie, E. L.; Steefel, C.; Nico, P. S.; Han, R.

    2010-12-01

    Microbially mediated Cr(VI) reduction at the Hanford 100H area was investigated by flow-through column experiments. Three separate experiments were conducted to promote microbial activities associated with denitrification, iron and sulfate reduction, respectively. Replicate columns packed with natural sediments from the site under anaerobic environment were injected with 5mM Lactate as the electron donor and 5 μM Cr(VI) in all experiments. Sulfate and nitrate solutions were added to act as the main electron acceptors in the respective experiments, while iron columns relied on the indigenous sediment iron (and manganese) oxides as electron acceptors. Column effluent solutions were analyzed by IC and ICP-MS to monitor the microbial consumption/conversion of lactate and the associated Cr(VI) reduction. Biogeochemical reactive transport modeling was performed to gain further insights into the reaction mechanisms and Cr(VI) bioreduction rates. All experimental columns showed a reduction of the injected Cr(VI). Columns under denitrifying conditions showed the least Cr(VI) reduction at early stages (adverse effect on Cr(VI) reduction rates. Reactive transport simulations indicated that biomass growth completely depleted influent ammonium, and called for an additional source of N to account for the measured reduction rates. Iron columns were the least active with undetectable consumption of the injected lactate, slowest cell growth, and the smallest change in Cr(VI) concentrations during the course of the experiment. In contrast, columns under sulfate-reducing/fermentative conditions exhibited the greatest Cr(VI) reduction capacity. Two sulfate columns evolved to complete lactate fermentation with acetate and propionate produced in the column effluent after 40 days of experiments. These fermenting columns showed a complete removal of injected Cr(VI), visible precipitation of sulfide minerals, and a significant increase in effluent Fe and Mn concentrations. Reactive

  13. Numerical simulation of hydrodynamics in a pump-turbine at off-design operating conditions in turbine mode

    Science.gov (United States)

    Yan, J. P.; Seidel, U.; Koutnik, J.

    2012-11-01

    The hydrodynamics of a reduced-scaled model of a radial pump-turbine is investigated under off-design operating conditions, involving runaway and "S-shape" turbine brake curve at low positive discharge. It is a low specific speed pump-turbine machine of Francis type with 9 impeller blades and 20 stay vanes as well as 20 guide vanes. The computational domain includes the entire water passage from the spiral casing inlet to the draft tube outlet. Completely structured hexahedral meshes generated by the commercial software ANSYS-ICEM are employed. The unsteady incompressible simulations are performed using the commercial code ANSYS-CFX13. For turbulence modeling the standard k-ε model is applied. The numerical results at different operating points are compared to the experimental results. The predicted pressure amplitude is in good agreement with the experimental data and the amplitude of normal force on impeller is in reasonable range. The detailed analysis reveals the onset of the flow instabilities when the machine is brought from a regular operating condition to runaway and turbine break mode. Furthermore, the rotating stall phenomena are well captured at runaway condition as well as low discharge operating condition with one stall cell rotating inside and around the impeller with about 70% of its frequency. Moreover, the rotating stall is found to be the effect of rotating flow separations developed in several consecutive impeller channels which lead to their blockage. The reliable simulation of S-curve characteristics in pump-turbines is a basic requirement for design and optimization at off-design operating conditions.

  14. Sufficient Condition for Estimation in Designing H∞ Filter-Based SLAM

    Directory of Open Access Journals (Sweden)

    Nur Aqilah Othman

    2015-01-01

    Full Text Available Extended Kalman filter (EKF is often employed in determining the position of mobile robot and landmarks in simultaneous localization and mapping (SLAM. Nonetheless, there are some disadvantages of using EKF, namely, the requirement of Gaussian distribution for the state and noises, as well as the fact that it requires the smallest possible initial state covariance. This has led researchers to find alternative ways to mitigate the aforementioned shortcomings. Therefore, this study is conducted to propose an alternative technique by implementing H∞ filter in SLAM instead of EKF. In implementing H∞ filter in SLAM, the parameters of the filter especially γ need to be properly defined to prevent finite escape time problem. Hence, this study proposes a sufficient condition for the estimation purposes. Two distinct cases of initial state covariance are analysed considering an indoor environment to ensure the best solution for SLAM problem exists along with considerations of process and measurement noises statistical behaviour. If the prescribed conditions are not satisfied, then the estimation would exhibit unbounded uncertainties and consequently results in erroneous inference about the robot and landmarks estimation. The simulation results have shown the reliability and consistency as suggested by the theoretical analysis and our previous findings.

  15. Evaluation of fracture resistance of ceramic veneers with different preparation designs and loading conditions: An in vitro study.

    Science.gov (United States)

    Arora, Aman; Upadhyaya, Viram; Arora, Sheen J; Jain, Prachi; Yadav, Avneet

    2017-01-01

    The purpose of this study was to evaluate the effect of incisal butt joint and incisal overlap design on the fracture resistance of ceramic veneers under two different loading conditions, i.e., 125° and 60° representing protrusive and intercuspal movements, respectively. Thirty-two maxillary central incisors were divided into two groups of sixteen specimens each and were prepared with incisal butt joint and incisal overlap design. Ceramic veneers were fabricated and cemented. Both the groups were further divided and mechanical testing to evaluate the fracture resistance were done using the universal testing machine. The values were recorded in Newton along with the assessment of the failure mode of both veneer and the tooth. Unpaired t-test showed a significant difference (P veneers with butt joint design; however, there was no significant difference (P > 0.05). Failure mode of teeth showed more number of coronal fracture followed by cervical fracture and root fracture, but there was no significant difference between the two groups (P > 0.05). Butt joint design had higher fracture resistance than palatal overlap design. Under functional loads for both designs, fracture resistance was higher at 125° than at 60° angle.

  16. Reduction in Design Stability Number of Monolayer Armour Units for Singular Conditions of Projects in Rubble Mound Breakwaters

    Directory of Open Access Journals (Sweden)

    Hugo Juan Donini

    2015-07-01

    Full Text Available The evaluation of concrete single layer of breakwaters is based on the application of design coefficients obtained in laboratory tests, primarily two-dimensional and under controlled conditions. With the experience of more than 30 years in structures of this type in the world, it is important to compare the values of stability numbers used in the design with those who are in breakwaters as built. In this paper, update and increase the data collected with respect to previous publications, developing an analysis of particular situations in which the amour layer stability coefficients are reduced. A series of Accropode® and Core-LocTM recommendations concerning the design elements is also made. Also there are conclusions related to increases in the volume and the reduction in the number of blocks needed for different numbers of stability proposed.

  17. A MATLAB Graphical User Interface Dedicated to the Optimal Design of the High Power Induction Motor with Heavy Starting Conditions

    Directory of Open Access Journals (Sweden)

    Maria Brojboiu

    2014-09-01

    Full Text Available In this paper, a Matlab graphical user interface dedicated to the optimal design of the high power induction motor with heavy starting conditions is presented. This graphical user interface allows to input the rated parameters, the selection of the induction motor type and the optimization criterion of the induction motor design also. For the squirrel cage induction motor the graphical user interface allows the selection of the rotor bar geometry, the material of the rotor bar as well as the fastening technology of the shorting ring on the rotor bar. The Matlab graphical user interface is developed and applied to the general optimal design program of the induction motor described in [1], [2].

  18. Experimental design strategies in the optimization and robustness testing of adsorptive stripping voltammetric conditions for kynurenic acid determination.

    Science.gov (United States)

    Furlanetto, S; Pinzauti, S; Gratteri, P; La Porta, E; Calzeroni, G

    1997-06-01

    Experimental design was used for the optimization and robustness testing of an adsorptive stripping voltammetric procedure for kynurenic acid determination. The optimization of the peak height response proceeded through a screening phase (D-optimal design strategy) followed by a response surface study (Doehlert design) applied to the variables pH, pulse amplitude and stirring rate. An interaction between pH and stirring rate was pointed out. The optimized method was validated and the variation of factors that was expected to occur in practice was simulated in a robustness test. A composite fractional matrix for the evaluation of method robustness was used and pH emerged as the only critical factor. The linear range found applying the optimized conditions was 2.5 x 10(-9) to 2.5 x 10(-7) M and the calculated limit of detection was 1.72 x 10(-9) M.

  19. Optimizing conditions for the development process of the sponge liquid bread mold through a factorial design

    Directory of Open Access Journals (Sweden)

    Claudia Marcela Quintero Gil

    2008-06-01

    Full Text Available The bread in its many forms is one of the oldest and most widely food consumed by humanity, its appearance is not known for sure, but it is presumed that he was in the Middle East, where he began to cultivate wheat. Due to its development in different cultures have been many developments in technology and industry, however all the processes that are designed to make bread have had a common purpose and simple, the conversion of wheat four in a food spongy and appetizing. This objective has been achieved through a series of stages are common as the mixture of water and four with yeast, salt and other ingredients individuals in appropriate proportions; the generation of specific aroma and favor through fermentation and the development a structure of gluten in combination with the application of mechanical energy during the kneading and the subsequent acquisition of a fixed and final structure consistent with a nice color through the baking.To achieve this goal which is based on the fermentation of the baking industry has created the term to refer to a sponge pre whose primary function is precisely to change the favor and aroma and contribute to the development of the mass through changes in the properties rheological properties of the mixture. Among the ingredients of the sponge is drawn to the food for yeast known as (APL that has the primary role of regulating the fermentation through the right mix of ingredients both qualitatively and quantitatively.The study of this combination was raised in this paper using a factorial design of experiments with statistical treatment looking to evaluate the effects of the formulation in combination with the temperature on a response variable called gasification power which indirectly measured the development of the fermentation Liquid sponges that serve as a basis for the preparation of bread mold. The results made it possible to defne a design and the apl an optimum temperature at which the variable response

  20. Design of Controlled Processing Conditions for Drop Forgings Made of Microalloy Steel Grades for Mining Industry

    Directory of Open Access Journals (Sweden)

    Skubisz P.

    2015-04-01

    Full Text Available Effect of plastic processing and controlled cooling on microstructure and mechanical properties of experimental steel grades with microalloyed with Ti, V and/or Nb, varying in the content of Mo is presented as an offer for mining industry for replacement traditionally heat-treatable hardenability grades. The goal of the work is producing microstructure condition, which after controlled hot forging and direct heat treatment, involving quenching and self-tempering, are meant to provide good combination of mechanical properties, such as TYS 800 MPa, UTS 1050 MPa, elongation to fracture at least A5 15% and/or impact strength at room temperature KCV 60 J/cm2. Hardenability assessment and dilatometric examination allowed formulation of direct heat treatment guidelines, taking into consideration fields of temperature and strain in a typical hot forging process, estimated numerically, with the use of plastometric tests results, as well as the use of unique cooling cycles after forging.

  1. Mechanical Safety Subcommittee Guideline for Design of Thin Windows Regarding Roark’s Edge Condition Coefficient

    Energy Technology Data Exchange (ETDEWEB)

    Ader, C. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Voirin, E. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); McGee, M. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Nobrega, L. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2017-06-15

    An error was found in an edge stress coefficient used to calculate stresses in thin windows. This error is present in “Roark’s Formulas for Stress and Strain” 7th and 8th Edition. The 6th Edition is correct. This guideline specially discusses a major difference in regards to a coefficient used in calculating the edge stress in “Roark’s Formulas for Stress and Strain” 6th Edition compared to the 7th and 8th Editions. In Chapter 10: Flat Plates under “Circular plates under distributed load producing large deflections,” Case 3, which is “Fixed and held. Uniform pressure q over entire plate.” The coefficient for a fixed edge condition in the 6th Edition1 K4 = 0.476 while in the 7th and 8th Edition2, the coefficient is 1.73 which is significant difference.

  2. Improving conditions for reuse of design solutions - by means of a context based solution library

    DEFF Research Database (Denmark)

    Mortensen, Niels Henrik; Grothe-Møller, Thorkild; Andreasen, Mogens Myrup

    1997-01-01

    Among the most important reasoning mechanisms in design is reasoning by analogy. One precondition for being able to reason about the properties and functionalitues of a product or subsystem is that the context of the solution is known. This paper presents a computer based solution library where...... solutions have context. The library has aluminium technology as application area and has been developed in co-operation between the Technical University of Denmark, SkanAluminium and leading aluminium companies within Scandinavia. The library has been tested in a number of companies and good results have...... been obtained. So fare more than 400 companies, universities and engineering academies have decided to utilise the solution library...

  3. Thermal Analysis of the Vulnerability of the Spacesuit Battery Design to Short-Circuit Conditions (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, G. H.; Chaney, L.; Smith, K.; Pesaran, A.; Darcy, E.

    2010-04-22

    NREL researchers created a mathematical model of a full 16p-5s spacesuit battery for NASA that captures electrical/thermal behavior during shorts to assess the vulnerability of the battery to pack-internal (cell-external) shorts. They found that relocating the short from battery pack-external (experimental validation) to pack-internal (modeling study) causes substantial additional heating of cells, which can lead to cell thermal runaway. All three layers of the bank-to-bank separator must fail for the pack-internal short scenario to occur. This finding emphasizes the imperative of battery pack assembly cleanliness. The design is tolerant to pack-internal shorts when stored at 0% state of charge.

  4. Implementation of Forest Condition Index (FCI as an input for the design of forest public policies in Mexico

    Directory of Open Access Journals (Sweden)

    Neyra Sosa Gutierrez

    2017-03-01

    Full Text Available Public policies (PP are defined as actions designed, implemented and evaluated by governments operating through programs, with the ultimate goal to improve and solve social problems in the short and long term. I theory, PP should be designed considering, among other things, basic social, economic and environmental information of the areas where such programs derived. However, a common deficiency in the design of public policies for the management of forest resources in Mexico is the lack of analysis in the complexity of a territorial context, which directly affects the results of the PP. This variable is relevant in Mexico, due to the great heterogeneity of the territory, so the results in the implementation of programs and projects arising from forest PP, usually lacks of a fundamental theoretical basis for obtaining better results. Thus, the objective of this study is the development of a methodological framework that incorporates the spatial variable to improve the design of forest PP ad hoc to each territory. The Forest Condition Index (FCI was designed and implemented as an instrument to provide a robust spatial reference by assessing forest condition in contrast to the degree of marginalization of municipal entities. The inputs for the FCI describes the dynamics of the degree of marginalization and the dynamics of plant cover during the period 2000-2010 of all municipalities in the state of Michoacan, used as a study case. The application of the FCI to the 113 municipalities in the state, results in the categorization of municipalities in 4 classes, depicting possible trends between marginalization and forest cover. The largest number of municipalities (31, which represents 35.78% of the state's land, were grouped in class IV, indicating a trend in the increase the index of marginalization and the decrease in forest cover. Only 26 municipalities were located in Class I, revealed a favorable trend with a decreasing rate of marginalization

  5. BIOSORPTION OF CHROMIUM (VI) USING IMMOBILIZED ...

    African Journals Online (AJOL)

    USER

    2016-05-20

    May 20, 2016 ... water and air. It affects the growth of flora and fauna which in turn affect human health negatively. Chromium could also bio-accumulate in plants and animals and this becomes ... The sorption kinetic models of Cr (VI) onto the biosorbents were examined with ... bulk density, moisture and ash contents.

  6. 76 FR 60593 - Title VI; Proposed Circular

    Science.gov (United States)

    2011-09-29

    ... for FTA staff to make oral presentations about the two proposed Circulars and allow attendees an... proposed Circular would incorporate lessons learned from triennial reviews, discretionary Title VI... Implementation Plan for Limited English Proficient (LEP) persons now contains a summary of the DOT LEP guidance...

  7. Prospek pengembangan industri perkulitan pada pelita VI

    OpenAIRE

    D. Karyadi

    1995-01-01

    The leather industry is one of the strong competitive industry, as it comes from renewable natural resources. Therefore, the leather industry has good prospect to develop at the Pelita VI to be the industrial products export competitive. To develop leather industry and leather products should be given closed attention and well managed, especially concerning raw material supply, quality and leather waste treatment.

  8. Resúmenes Presentaciones Orales VI ECAP

    OpenAIRE

    Vargas Arana, Editor Gabriel

    2016-01-01

    En este artículo se pueden encontrar los resúmenes de las presentaciones orales del VI Ecuentro Científico de la Amazonía Peruana, desarrollado el 27 y 28 de cotubre de 2015 en la ciudad de Iquitos, Perú.

  9. Vi har selv designet naturens love

    DEFF Research Database (Denmark)

    Bentzen, Martin Mose

    2014-01-01

    ForskerZonenNaturlovene er universelt gyldige i de flestes øjne. De gælder altid, uanset hvad vi tænker. Men dette billede står ikke uimodsagt i videnskabsfilosofien, og der er meget, der tyder på, at det ikke er specielt empirisk korrekt...

  10. Chromium(VI) bioremediation by probiotics.

    Science.gov (United States)

    Younan, Soraia; Sakita, Gabriel Z; Albuquerque, Talita R; Keller, Rogéria; Bremer-Neto, Hermann

    2016-09-01

    Chromium is a common mineral in the earth's crust and can be released into the environment from anthropogenic sources. Intake of hexavalent chromium (Cr(VI)) through drinking water and food causes toxic effects, leading to serious diseases, and is a commonly reported environmental problem. Microorganisms can mitigate or prevent the toxic effects caused by heavy metals in addition to having effective resistance mechanisms to prevent cell damage and bind to these metals, sequestering them from the cell surface and removing them from the body. Species of Lactobacillus, Streptococcus, Bacillus and Bifidobacterium present in the human mouth and gut and in fermented foods have the ability to bind and detoxify some of these substances. This review address the primary topics related to Cr(VI) poisoning in animals and humans and the use of probiotics as a way to mitigate or prevent the toxic effects caused by Cr(VI). Further advances in the genetic knowledge of such microorganisms may lead to discoveries which will clarify the most active microorganisms that act as bioprotectants in bodies exposed to Cr(VI) and are an affordable option for people and animals intoxicated by the oral route. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. 77 FR 52116 - Title VI; Final Circular

    Science.gov (United States)

    2012-08-28

    ... enforcement of Title VI disparate impact regulations, it did not undermine the validity of those regulations... streamlined this process. We have modified the definition of ``disparate impact'' for clarity. We decline to... process reengineering. In response, FTA will review the public engagement plan and its implementation when...

  12. Hvem er vi? Hvem er de?

    DEFF Research Database (Denmark)

    Kryger, Niels

    2016-01-01

    Kommentaren tager afsæt i initiativer i de pædagogiske faglige foreninger i Europa EERA) og i Norden (NERA) og argumenterer for at det er forpligtelse for os som nordiske og europæiske pædagogiske forskere at gå op imod de stadigt mere ekskluderende vi-konstruktioner, som er blevet formuleret i for...

  13. Influence of preparation design and existing condition of tooth structure on load to failure of ceramic laminate veneers.

    Science.gov (United States)

    Schmidt, Kyle K; Chiayabutr, Yada; Phillips, Keith M; Kois, John C

    2011-06-01

    Although investigators have evaluated the effect of ceramic veneer preparation design, limited information is available regarding preparation design in association with the condition of existing tooth structure. The purpose of this in vitro study was to evaluate the effect of preparation design and the amount of existing tooth structure on the fracture resistance of pressable ceramic laminate veneers. Thirty-two extracted human maxillary central incisors were allocated into 4 groups (n=8) to test for 2 variables: (1) the preparation design (a 2 mm incisal reduction shoulder finish line with or without palatal chamfer) and (2) the existing amount of tooth structure (non-worn tooth or worn tooth). Measurement of the remaining enamel thickness on the inciso-occlusal surface was made after the tooth was prepared. All prepared teeth were restored with pressable ceramic (IPS Empress) veneers, and the veneers were luted with resin cement (Rely-X Veneer). These luted specimens were loaded to failure in a universal testing machine, in the compression mode, with a crosshead speed of 0.05 mm/min. The data were analyzed using a 2-way ANOVA and Tukey's HSD multiple comparison test (α=.05) Preparation design and the amount of existing tooth structure had a significant effect on the load to failure value (Ppreparation design and existing amount of tooth structure was not significant (P=.702). Mean (SD) load to failure values were as follows: a preparation design with a palatal chamfer margin with a non-worn tooth (166.67 N (28.89)) revealed a significantly higher failure load than the group with a shoulder finish line alone (131.84 N (18.88)) (Ppreparation design with a palatal chamfer margin for worn teeth (119.56 N (23.88)) revealed a significantly higher failure load than a shoulder finish line design alone (90.56 N (9.32)) (Ppreparation design with a shoulder finish line for worn teeth had a significantly lower failure load than those on non-worn teeth (PPreparation design

  14. Chromium(III) and chromium(VI) release from leather during 8 months of simulated use.

    Science.gov (United States)

    Hedberg, Yolanda S; Lidén, Carola

    2016-08-01

    Chromium (Cr) release from Cr-tanned leather articles is a major cause of Cr contact dermatitis. It has been suggested that Cr(VI) release from leather is not necessarily an intrinsic property of the leather, but is strongly dependent on environmental conditions. To test this hypothesis for long-term (8 months) simulated use. The release of total Cr and Cr(VI) from Cr-tanned, unfinished leather was analysed in subsequent phosphate buffer (pH 8.0) immersions for a period of 7.5 months. The effect of combined ultraviolet treatment and alkaline solution (pH 12.1) was tested. Dry storage [20% relative humidity (RH)] was maintained between immersions. Atomic absorption spectroscopy, X-ray fluorescence and diphenylcarbazide tests were used. Cr(VI) release was dependent on previous dry storage or alkaline treatment, but not on duration or number of previous immersions. Cr(III) release decreased with time. Fifty-two percent of the total Cr released during the last immersion period was Cr(VI). Cr(VI) release exceeded 9 mg/kg in all immersion periods except in the first 10-day immersion (2.6 mg/kg). Cr(VI) release is primarily determined by environmental factors (RH prior to immersion, solution pH, and antioxidant content). The RH should be kept low prior to testing Cr(VI) release from leather. © 2016 The Authors. Contact Dermatitis published by John Wiley & Sons Ltd.

  15. Distinguished Cr(VI) capture with rapid and superior capability using polydopamine microsphere: Behavior and mechanism.

    Science.gov (United States)

    Zhang, Qingrui; Li, Yixuan; Yang, Qinggang; Chen, He; Chen, Xinqing; Jiao, Tifeng; Peng, Qiuming

    2018-01-15

    Toxic heavy metal containing Cr(VI) species is a serious threat for ecological environment and human beings. In this work, a new mussel-inspired polydopamine microsphere (PDA-sphere) is prepared through in situ oxidative polymerization at air condition with controllable sizes. The adsorption of Cr(VI) ions onto PDA-sphere is highly pH dependent with the optimal pH ranging from 2.5 to 3.8. A rapid Cr(VI) removal can approach in 8min for equilibrium. More importantly, the prepared materials exhibit a remarkable sorption selectivity, coexisting SO42-, NO3- and Cl- ions at high levels; The applicability model further proves its effective performances with treated capacity of 42,000kg/kg sorbent, and the effluent can be reduced from 2000ppb to below 50ppb, which meets the drinking water criterions recommended by WHO. 1kg sorbent can also purify approximately 100t Cr(VI) contaminated wastewaters basing on the wastewater discharges of China. Such capacity for application ranks the top level for Cr(VI) removal. Additionally, the exhausted materials can be well regenerated by binary alkaline and salts mixtures. Such efficient adsorption can be ascribed to the well-dispersed morphology as well as the strong affinity between Cr(VI) and catechol or amine groups by XPS investigation. All the results suggest that polydopamine microspheres may be ideal materials for Cr(VI) treatment in waters. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Designing and implementing a longitudinal study of children with neurological, genetic or metabolic conditions: charting the territory

    Directory of Open Access Journals (Sweden)

    Davies Betty

    2010-09-01

    Full Text Available Abstract Background Children with progressive metabolic, neurological, or chromosomal conditions and their families anticipate an unknown lifespan, endure unstable and often painful symptoms, and cope with erratic emotional and spiritual crises as the condition progresses along an uncertain trajectory towards death. Much is known about the genetics and pathophysiology of these diseases, but very little has been documented about the trajectory of symptoms for children with these conditions or the associated experience of their families. A longitudinal study design will help to close this gap in knowledge. Methods/Design Charting the Territory is a longitudinal descriptive, correlational study currently underway with children 0-19 years who are diagnosed with progressive neurological, metabolic, or chromosomal conditions and their families. The purpose of the study is to determine and document the clinical progression of the condition and the associated bio-psychosocial-spiritual experiences of the parents and siblings age 7-18 years. Approximately 300 families, both newly diagnosed children and those with established conditions, are being recruited in six Canadian cities. Children and their families are being followed for a minimum of 18 months, depending on when they enroll in the study. Family data collection will continue after the child's death if the child dies during the study period. Data collection includes monthly parental assessment of the child's symptoms; an annual functional assessment of the child; and completion of established instruments every 6 months by parents to assess family functioning, marital satisfaction, health status, anxiety, depression, stress, burden, grief, spirituality, and growth, and by siblings to assess coping and health. Impact of participation on parents is assessed after 1 year and at the end of the study. Chart reviews are conducted at enrollment and at the conclusion of the study or at the time of the

  17. Characterization of multifarious plant growth promoting traits of rhizobacterial strain AR6 under Chromium (VI) stress.

    Science.gov (United States)

    Karthik, Chinnannan; Elangovan, Namasivayam; Kumar, Thamilarasan Senthil; Govindharaju, Subramani; Barathi, Selvaraj; Oves, Mohammad; Arulselvi, Padikasan Indra

    2017-11-01

    Plant growth promoting rhizobacteria (PGPR) can increase the host plant tolerance to cope up with heavy metal induced stress, which can be improve plant growth. Thus, the present study was designed to isolate Cr(VI) tolerant PGPR strain and evaluate its plant growth promoting (PGP) properties under Cr(VI) stress. Rhizobacterial strain AR6 was isolated from the rhizosphere of Phaseolus vulgaris L. and showed 99% homology with Cellulosimicrobium funkei (KM032184) in BLASTn analysis. Strain AR6 was specifically selected due to its high Cr(VI) tolerance (1200μg/ml) and substantial production of PGP substances. Strain AR6 produced 36.75μg/ml of indole acetic acid (IAA), 60.40μg/ml of ammonia and 14.23μg/ml of exopolysaccharide (EPS). Moreover, strain AR6 showed positive results for catalase, protease, amylase, lipase production and phosphate solubilization. A trend of Cr(VI) concentration dependent progressive decline for PGP traits of strain AR6 was observed excluding EPS which was regularly increased on increasing concentrations of Cr(VI). Among the four tested Cr(VI) concentrations, 250μg/ml showed the maximum toxicity to PGP activities of strain AR6. Inoculation of rhizobacterial strain AR6 significantly increased the root length of test crops in the presence of Cr(VI) and produced a considerable number of colonizes on the root of versatile dicot and monocot plants. Moreover, strain AR6 exhibited strong antagonistic activity against phytopathogen Aspergillus niger. Thus, the present study suggests that metal tolerant and PGP activities of the rhizobacterial strain AR6 could be exploited for environmental and agricultural issues. Copyright © 2017 Elsevier GmbH. All rights reserved.

  18. Conditioning of red mud for subsequent titanium and scandium recovery. A conceptual design study

    Energy Technology Data Exchange (ETDEWEB)

    Alkan, G.; Xakalashe, B.; Kaussen, F.; Friedrich, Bernd [RWTH Aachen Univ. (Germany). IME Inst. of Process Metallurgy and Metal Recycling; Yagmurlu, B. [RWTH Aachen Univ. (Germany). IME Inst. of Process Metallurgy and Metal Recycling; MEAB Chemie Technik GmbH, Aachen (Germany)

    2017-03-15

    Leaching experiments were undertaken on red mud materials (red mud and red mud slag). The red mud slag was produced via the carbothermic reduction of red mud at high temperatures (T > 1500 C) via SAF treatment. Furthermore, iron was recovered in the smelting step to the metal phase. Ti and Sc were successfully recovered from the red mud materials by hydrometallurgical treatment. For both critical metals, it was found that sulfuric acid was the best mineral acid among others. Since direct red mud leaching had some shortcomings, a route designed to overcome them is proposed. For optimal Ti and Sc recovery from red mud a promising process flowsheet combining pyrometallurgical and hydrometallurgical treatment is proposed as follows: pyrometallurgical processing (fluxed smelting to produce calcium oxide based slag phases and controlled cooling for crystalline and glassy slags), leaching for maximized Ti- and Sc extraction and followed by a multistage precipitation (for metal recovery and solution purification). Initial trial results showed that the proposed process is promising.

  19. Design and Application of a High Sensitivity Piezoresistive Pressure Sensor for Low Pressure Conditions

    Directory of Open Access Journals (Sweden)

    Huiyang Yu

    2015-09-01

    Full Text Available In this paper, a pressure sensor for low pressure detection (0.5 kPa–40 kPa is proposed. In one structure (No. 1, the silicon membrane is partly etched to form a crossed beam on its top for stress concentration. An aluminum layer is also deposited as part of the beam. Four piezoresistors are fabricated. Two are located at the two ends of the beam. The other two are located at the membrane periphery. Four piezoresistors connect into a Wheatstone bridge. To demonstrate the stress concentrate effect of this structure, two other structures were designed and fabricated. One is a flat membrane structure (No. 2, the other is a structure with the aluminum beam, but without etched silicon (No. 3. The measurement results of these three structures show that the No.1 structure has the highest sensitivity, which is about 3.8 times that of the No. 2 structure and 2.7 times that of the No. 3 structure. They also show that the residual stress in the beam has some backside effect on the sensor performance.

  20. Design and Application of a High Sensitivity Piezoresistive Pressure Sensor for Low Pressure Conditions.

    Science.gov (United States)

    Yu, Huiyang; Huang, Jianqiu

    2015-09-08

    In this paper, a pressure sensor for low pressure detection (0.5 kPa-40 kPa) is proposed. In one structure (No. 1), the silicon membrane is partly etched to form a crossed beam on its top for stress concentration. An aluminum layer is also deposited as part of the beam. Four piezoresistors are fabricated. Two are located at the two ends of the beam. The other two are located at the membrane periphery. Four piezoresistors connect into a Wheatstone bridge. To demonstrate the stress concentrate effect of this structure, two other structures were designed and fabricated. One is a flat membrane structure (No. 2), the other is a structure with the aluminum beam, but without etched silicon (No. 3). The measurement results of these three structures show that the No.1 structure has the highest sensitivity, which is about 3.8 times that of the No. 2 structure and 2.7 times that of the No. 3 structure. They also show that the residual stress in the beam has some backside effect on the sensor performance.

  1. Permeable Reactive Barriers Designed To Mitigate Eutrophication Alter Bacterial Community Composition and Aquifer Redox Conditions

    Science.gov (United States)

    Hiller, Kenly A.; Foreman, Kenneth H.; Weisman, David

    2015-01-01

    Permeable reactive barriers (PRBs) consist of a labile carbon source that is positioned to intercept nitrate-laden groundwater to prevent eutrophication. Decomposition of carbon in the PRB drives groundwater anoxic, fostering microbial denitrification. Such PRBs are an ideal habitat to examine microbial community structure under high-nitrate, carbon-replete conditions in coastal aquifers. We examined a PRB installed at the Waquoit Bay National Estuarine Research Reserve in Falmouth, MA. Groundwater within and below the PRB was depleted in oxygen compared to groundwater at sites upgradient and at adjacent reference sites. Nitrate concentrations declined from a high of 25 μM upgradient and adjacent to the barrier to <0.1 μM within the PRB. We analyzed the total and active bacterial communities filtered from groundwater flowing through the PRB using amplicons of 16S rRNA and of the 16S rRNA genes. Analysis of the 16S rRNA genes collected from the PRB showed that the total bacterial community had high relative abundances of bacteria thought to have alternative metabolisms, such as fermentation, including candidate phyla OD1, OP3, TM7, and GN02. In contrast, the active bacteria had lower abundances of many of these bacteria, suggesting that the bacterial taxa that differentiate the PRB groundwater community were not actively growing. Among the environmental variables analyzed, dissolved oxygen concentration explained the largest proportion of total community structure. There was, however, no significant correlation between measured environmental parameters and the active microbial community, suggesting that controls on the active portion may differ from the community as a whole. PMID:26231655

  2. SMALL SAMPLE SIZE IN 2X2 CROSS OVER DESIGNS: CONDITIONS OF DETERMINATION

    Directory of Open Access Journals (Sweden)

    B SOLEYMANI

    2001-09-01

    Full Text Available Introduction. Determination of small sample size in some clinical trials is a matter of importance. In cross-over studies which are one types of clinical trials, the matter is more significant. In this article, the conditions in which determination of small sample size in cross-over studies are possible were considered, and the effect of deviation from normality on the matter has been shown. Methods. The present study has been done on such 2x2 cross-over studies that variable of interest is quantitative one and is measurable by ratio or interval scale. The method of consideration is based on use of variable and sample mean"s distributions, central limit theorem, method of sample size determination in two groups, and cumulant or moment generating function. Results. In normal variables or transferable to normal variables, there is no restricting factors other than significant level and power of the test for determination of sample size, but in the case of non-normal variables, it should be determined such large that guarantee the normality of sample mean"s distribution. Discussion. In such cross over studies that because of existence of theoretical base, few samples can be computed, one should not do it without taking applied worth of results into consideration. While determining sample size, in addition to variance, it is necessary to consider distribution of variable, particularly through its skewness and kurtosis coefficients. the more deviation from normality, the more need of samples. Since in medical studies most of the continuous variables are closed to normal distribution, a few number of samples often seems to be adequate for convergence of sample mean to normal distribution.

  3. Influence of operational parameters and kinetics analysis on the photocatalytic reduction of Cr(VI) by immobilized ZnO.

    Science.gov (United States)

    Behnajady, Mohammad A; Mansoriieh, Nafiseh; Modirshahla, Nasser; Shokri, Mohammad

    2012-01-01

    In the present work the performance of immobilized ZnO on a glass plate with the heat attachment method has been described for photoreduction of Cr(VI) to the less harmful Cr(III) at different operational parameters. The photoreduction of Cr(VI) on the surface of the immobilized ZnO catalyst was studied as a function of the pH of solution, initial Cr(VI) concentration and ultraviolet (UV) light intensity. Results indicated that the reduction rate decreases with increasing initial concentration of Cr(VI) and initial pH of solution, whereas it increases with increasing UV light intensity. The photoreduction rate of Cr(VI) on the surface of the immobilized ZnO in the presence of O2 as mobile gas is more than Ar and N2. The reduction process of Cr(VI) by immobilized ZnO also could be done under visible light irradiation. Pseudo first-order kinetics were observed for the photoreduction of Cr(VI) at different operational conditions. With non-linear regression analysis a mathematical kinetics model was developed for the pseudo first-order constant (k(ap)) as a function of operational parameters.

  4. Study of the involved sorption mechanisms of Cr(VI) and Cr(III) species onto dried Salvinia auriculata biomass.

    Science.gov (United States)

    Módenes, Aparecido Nivaldo; de Oliveira, Ana Paula; Espinoza-Quiñones, Fernando R; Trigueros, Daniela Estelita Goes; Kroumov, Alexander Dimitrov; Bergamasco, Rosângela

    2017-04-01

    Removal of Cr(VI) species by dried biomass of the aquatic macrophyte Salvinia auriculata was studied in order to understand the involved sorption mechanisms. Kinetic tests were carried out under the conditions such as concentration range of Cr(VI) from 50 to 250 mg L-1 and a temperature of 30 °C. Modification of the biosorbent by the presence of Cr(VI) species was assessed by analysis of its porosity, density and infrared molecular absorption spectrum. A series of experimental approaches involving directed chemical modifications on the biosorbent surface was performed. The main functional groups involved in the sorption mechanisms were identified. The gas sorption analyser was applied and proved that a strong chemical effect of Cr(VI) species on the surface took place, resulting in a leaching organic matter with an obvious and significant increase in the porosity parameters. The intra-particle diffusion model revealed different mass transfer zones into the adsorbent during Cr(VI) removal. New combined Langmuir and Dubinin-Radushkevich isotherm was the best to fit the equilibrium data of Cr(VI) species removal. Finally, Cr(VI) removal was mainly mediated by a redox process where Cr(III) species were formed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Single and combined removal of Cr(VI) and Cd(II) by nanoscale zero-valent iron in the absence and presence of EDDS.

    Science.gov (United States)

    Dong, Haoran; Zeng, Yalan; Xie, Yankai; He, Qi; Zhao, Feng; Wang, Yang; Zeng, Guangming

    2017-09-01

    This study examined the feasibility of nanoscale zero-valent iron (nZVI) for the single and combined removal of Cr(VI) and Cd(II) with or without ethylene diamine disuccinic acid (EDDS). The effects of pH and dissolved oxygen (DO) on the removal process were investigated. Results show that the single removal of either Cr(VI) or Cd(II) by nZVI was pH dependent, where the higher Cr(VI) removal was achieved under acidic conditions, whereas the higher Cd(II) removal was achieved under alkaline conditions. The presence of DO enhanced Cd(II) removal but inhibited Cr(VI) removal under alkaline conditions. In the co-existence of Cr(VI) and Cd(II), it was found that Cd(II) exerted insignificant effect on Cr(VI) removal, while the presence of Cr(VI) remarkably enhanced the Cd(II) removal. The addition of EDDS exhibited different influences on Cr(VI) and Cd(II) removal, which were associated with pH and DO. The EDDS enhanced Cr(VI) removal at pH 5.6-9.0 in the absence of DO, but decreased Cr(VI) removal at pH 9.0 in the presence of DO. For the removal of Cd(II) at pH 5.6-7.0, either facilitation or inhibition effect of EDDS was observed, depending on EDDS concentration and the co-existence of Cr(VI). However, Cd(II) removal was always significantly inhibited by EDDS at pH 9.0.

  6. USE OF MICRO X-RAY ABSORPTION SPECTROSCOPY AND DIFFRACTION TO DELINEATE Cr(VI) SPECIATION IN COPR

    Energy Technology Data Exchange (ETDEWEB)

    CHRYSOCHOOU, M.; MOON, D. H.; FAKRA, S.; MARCUS, M.; DERMATAS, D.; CHRISTODOULATOS, C.

    2010-06-22

    The speciation of Cr(VI) in Cromite Ore Processing Residue was investigated by means of bulk XRD, and a combination of micro-XRF, -XAS and -XRD at the Advanced Light Source (ALS), Berkeley, CA, U.S.A.. Bulk XRD yielded one group of phases that contained explicitly Cr(VI) in their structure, Calcium Aluminum Chromium Oxide Hydrates, accounting for 60% of the total Cr(VI). Micro-analyses at ALS yielded complimentary information, confirming that hydrogarnets and hydrotalcites, two mineral groups that can host Cr(VI) in their structure by substitution, were indeed Cr(VI) sinks. Chromatite (CaCrO4) was also identified by micro-XRD, which was not possible with bulk methods due to its low content. The acquisition of micro-XRF elemental maps enabled not only the identification of Cr(VI)-binding phases, but also the understanding of their location within the matrix. This information is invaluable when designing Cr(VI) treatment, to optimize release and availability for reduction.

  7. Cloning and expression of a Vi mimotope of Salmonella enterica ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-15

    Sep 15, 2009 ... A recombinant His-Vi protein of Salmonella enterica serovar Typhi was successfully constructed and cloned into an expression vector ... recombinant protein can be used to detect specific anti-Vi antibody produced by typhoid patients. Overall, the His-Vi ... E-mail: khchua@um.edu.my. Tel.:603-. 79676607.

  8. Bioreduction of Cr (VI) by potent novel chromate resistant alkaliphilic ...

    African Journals Online (AJOL)

    Isolation of Cr (VI) resistant alkaliphilic bacteria from sediment and water samples collected from Wadi Natrun hypersaline Soda lakes (located in northern Egypt), resulted in isolation of several alkaliphilic bacterial strains that can tolerate up to 2.94 g/l of Cr (VI) in alkaline medium. However, with increasing Cr (VI) ...

  9. (VI) from water by micro-alloyed aluminium composite (MAlC)

    African Journals Online (AJOL)

    driniev

    2004-07-03

    Jul 3, 2004 ... This paper deals with Cr(VI) ion removal from water, by micro-alloyed aluminium composite (MAlC), under flow conditions. In a water environment the MAlC acts as a strong reducing agent. Dissolving it in water is accompanied by the generation of Al(III) ions and reduction of water to H2, with OH– ions.

  10. The Reaction between Iron(II) Iodide and Potassium Dichromate(VI) in Acidified Aqueous Solution

    Science.gov (United States)

    Talbot, Christopher

    2013-01-01

    This "Science note" teaching lesson explores the possible reaction between the ions in a reaction mixture consisting of iron(II) iodide and potassium dichromate(VI) in acidified aqueous solution. The electrode potentials will be used to deduce any spontaneous reactions under standard thermodynamic conditions (298 K, 1 bar (approximately…

  11. Adsorption of Cu(II) and Cr(VI) ions by chitosan: Kinetics and ...

    African Journals Online (AJOL)

    drinie

    2001-01-01

    Jan 1, 2001 ... Current treatment for the removal of Cr. (VI) involves acid catalysed chemical reduction to Cr3+. The Cr3+ is then precipitated as hydroxide at alkaline conditions using either caustic or lime (Udaybhaskar et al., 1990). The presence of Cu (II) in wastewater is also a problem. Copper is used extensively by.

  12. Exon skipping mutations in collagen VI are common and are predictive for severity and inheritance

    NARCIS (Netherlands)

    Lampe, A.K.; Zou, Y.; Sudano, D.; O'Brien, K.K.; Hicks, D.; Laval, S.H.; Charlton, R.; Jimenez-Mallebrera, C.; Zhang, R.Z.; Finkel, R.S.; Tennekoon, G.; Schreiber, G.; van der Knaap, M.S.; Marks, H.; Straub, V.; Flanigan, K.M.; Chu, M.L.; Muntoni, F.; Bushby, K.M.D.; Bonnemann, c.g.

    2008-01-01

    Mutations in the genes encoding collagen VI (COL6A1, COL6A2, and COL6A3) cause Bethlem myopathy (BM) and Ullrich congenital muscular dystrophy (UCMD), two related conditions of differing severity. BM is a relatively mild dominantly inherited disorder characterized by proximal weakness and distal

  13. Investigation of unsteady flow-induced impeller oscillations of a single-blade pump under off-design conditions

    Science.gov (United States)

    Pei, J.; Dohmen, H. J.; Yuan, S. Q.; Benra, F.-K.

    2012-11-01

    The periodically unsteady flow-induced impeller oscillations for a single-blade pump are investigated both numerically and experimentally under off-design conditions. A partitioned strategy with load transfer method is selected for achieving successful fluid-structure interaction (FSI) simulations with strong two-way coupling. Three-dimensional, unsteady Reynolds-averaged Navier-Stokes equations are solved with a shear stress transport turbulence model for the fluid side, while a transient structure dynamic analysis with the finite element method is employed for the structure side. Radial deflections of the pump impeller are successfully measured using proximity sensors to validate the FSI results. The comparison of the deflection results focuses on both phase and amplitude aspects under different operational conditions. The FSI calculation results are confirmed by the experiment, but deviations are still observed for about half of an impeller rotation. Therefore, a rigorous analysis of the comparison between the angles of the obtained x and y components is carried out to understand the cause of the deviation. Meanwhile, the transient pressure measured at the casing by both computational fluid dynamics and experimental methods is qualitatively analyzed. Furthermore, hydrodynamic forces are also analyzed considering a strong FSI effect in both the rotating and stationary coordinate frame under off-design conditions to understand the behavior of the transient excitation forces, which directly lead to the rotor deflection.

  14. Offshore Resource Assessment and Design Conditions: A Data Requirements and Gaps Analysis for Offshore Renewable Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Dennis [National Renewable Energy Lab. (NREL), Golden, CO (United States); Frame, Caitlin [National Oceanic and Atmospheric Administration (NOAA), Washington, DC (United States); Gill, Carrie [National Oceanic and Atmospheric Administration (NOAA), Washington, DC (United States); Hanson, Howard [Florida Atlantic Univ., Boca Raton, FL (United States); Moriarty, Patrick [National Renewable Energy Lab. (NREL), Golden, CO (United States); Powell, Mark [National Oceanic and Atmospheric Administration (NOAA), Washington, DC (United States); Shaw, William J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wilczak, Jim [National Oceanic and Atmospheric Administration (NOAA), Washington, DC (United States); Wynne, Jason [Energetics, Columbia, MD (United States)

    2012-03-01

    The offshore renewable energy industry requires accurate meteorological and oceanographic (“metocean”) data for evaluating the energy potential, economic viability, and engineering requirements of offshore renewable energy projects. It is generally recognized that currently available metocean data, instrumentation, and models are not adequate to meet all of the stakeholder needs on a national scale. Conducting wind and wave resource assessments and establishing load design conditions requires both interagency collaboration as well as valuable input from experts in industry and academia. Under the Department of Energy and Department of Interior Memorandum of Understanding, the Resource Assessment and Design Condition initiative supports collaborative national efforts by adding to core atmospheric and marine science knowledge relevant to offshore energy development. Such efforts include a more thorough understanding and data collection of key metocean phenomena such as wind velocity and shear; low-level jets; ocean, tidal, and current velocities; wave characteristics; geotechnical data relating to surface and subsurface characteristics; seasonal and diurnal variations; and the interaction among these conditions. Figure 1 presents a graphical representation of some metocean phenomena that can impact offshore energy systems. This document outlines the metocean observations currently available; those that are not available; and those that require additional temporal-spatial coverage, resolution, or processing for offshore energy in an effort to gather agreed-upon, needed observations.

  15. Reading and reacting: from the research of border conditions to experimental methods in architectural and urban design

    Directory of Open Access Journals (Sweden)

    Marc Schoonderbeek

    2014-07-01

    Full Text Available It is in marginal urban areas, borders of states, territories and cities, that marginal urban practices tend to take place. Limits of “normal” behaviour are transgressed and social and political differences become apparent. Such sites, where “other” spatial conditions have emerged, and that are “teeming with suggestive meanings and unexpected potential” (Schoonderbeek 2010, have hardly been analysed and discussed within the contemporary architectural discourse. This paper addresses such marginal urban conditions from an experimental approach to urban analysis and architectural design.  Methods such as mapping, navigation, and literary techniques such as character and scenario are brought into play in the analysis of urban fringes, and in the speculative design of alternative urban realities. With this experimental approach comes as well a certain understanding and appreciation of the border as a space of simultaneity, much like the Aleph of Borges. Drawing on this literary connection, the last part of the text proposes a method for border analysis and design by means of seeking the borders between architecture and literature.

  16. Prevention of Cyberbullying and Cyber Victimization: Evaluation of the ViSC Social Competence Program

    Science.gov (United States)

    Gradinger, Petra; Yanagida, Takuya; Strohmeier, Dagmar; Spiel, Christiane

    2015-01-01

    It is well-documented that cyberbullying and victimization co-occur with traditional forms indicating that they share similar mechanisms. Therefore, it was hypothesized that the general antibullying program ViSC might also be effective in tackling these new forms of bullying. A longitudinal randomized control group design has been applied to…

  17. Inclusion of Indigenous Peoples in CONFINTEA VI and Follow-Up Processes

    Science.gov (United States)

    Morrison, Sandra L.; Vaioleti, Timote M.

    2011-01-01

    This paper discusses key issues raised by indigenous peoples during CONFINTEA VI and proposes strategies to enable them to participate in ongoing processes. Indigenous peoples are not involved in the design, implementation and monitoring of adult education programmes, and this often results in a "one-size-fits-all" model. This article…

  18. Biosorbent encapsulation in calcium alginate: Effects of process variables on Cr(VI) removal from solutions.

    Science.gov (United States)

    Šillerová, Hana; Komárek, Michael; Liu, Chang; Poch, Jordi; Villaescusa, Isabel

    2015-09-01

    Selected biosorbents, brewers draff and grape waste, have been encapsulated in calcium alginate beads and used for the removal of Cr(VI) from aqueous solutions. The effects of encapsulation variables, including the type of waste, the percentage of waste in the beads and the curing time of the beads in CaCl2, on the diameters of the beads and Cr(VI) sorption kinetics have been evaluated. In total, 21 different types of beads were produced. The diameters of the beads increased with increasing amounts of encapsulated biomaterial. Beads that contained grape waste were larger than those containing brewers draff. The most efficient beads for Cr(VI) removal were beads that contained 4% (w/w) of grape waste. No significant differences in the kinetics of Cr(VI) sorption were found with respect to the curing time variable in the case of grape waste calcium alginate beads. Statistical analysis confirmed that the type and percentage of waste are the critical parameters influencing the diameters of the beads and Cr(VI) removal. It was proven that the sorption efficiencies of the beads containing draff and grape waste encapsulated under the optimum conditions were much higher than the efficiencies obtained when using both wastes in their native states. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Biosorption of Cr(VI from Aqueous Solutions Using Trametes Versicolor Polyporus Fungi

    Directory of Open Access Journals (Sweden)

    M. Venkata Subbaiah

    2008-01-01

    Full Text Available Removal of chromium(VI from aqueous solution was studied using abundantly available trametes versicolor polyporus fungi as biosorbing medium under equilibrium and column flow conditions. Various sorption parameters such as contact time, effect of pH, concentration of Cr(VI and amount of biomass on the adsorption capacity of the biosorbent were studied. The equilibrium adsorption data were fitted to Freundlich and Langmuir adsorption isotherm models and the model parameters are evaluated. In addition, the data were used to predict the kinetics of adsorption. The results indicated that the adsorption of Cr(VI on fungi followed second order kinetics. The column flow adsorption data were used to predict break through curves. The fungi loaded with Cr(VI was regenerated with 0.1 M NaOH solution and the regenerated biomass was used in the subsequent adsorptiondesorption cycles. The experimental results demonstrated that the trametes versicolor polyporus fungi could be used as sorbent for immobilizing Cr(VI.

  20. Pneumothoraces in collagen VI-related dystrophy: a case series and recommendations for management

    Directory of Open Access Journals (Sweden)

    Kristin L. Fraser

    2017-06-01

    Full Text Available Collagen VI-related dystrophy (collagen VI-RD is a rare neuromuscular condition caused by mutations in the COL6A1, COL6A2 or COL6A3 genes. The phenotypic spectrum includes early-onset Ullrich congenital muscular dystrophy, adult-onset Bethlem myopathy and an intermediate phenotype. The disorder is characterised by distal hyperlaxity and progressive muscle weakness, joint contractures and respiratory insufficiency. Respiratory insufficiency is attributed to chest wall contractures, scoliosis, impaired diaphragmatic function and intercostal muscle weakness. To date, intrinsic parenchymal lung disease has not been implicated in the inevitable respiratory decline of these patients. This series focuses on pneumothorax, an important but previously under-recognised disease manifestation of collagen VI-RD. We describe two distinct clinical presentations within collagen VI-RD patients with pneumothorax. The first cohort consists of neonates and children with a single pneumothorax in the setting of large intrathoracic pressure changes. The second group is made up of adult patients with recurrent pneumothoraces, associated with chest computed tomography scan evidence of parenchymal lung disease. We describe treatment challenges in this unique population with respect to expectant observation, tube thoracostomy and open pleurodesis. Based on this experience, we offer recommendations for early identification of lung disease in collagen VI-RD and definitive intervention.

  1. Reactive transport modeling of chromium isotope fractionation during Cr(VI) reduction.

    Science.gov (United States)

    Jamieson-Hanes, Julia H; Amos, Richard T; Blowes, David W

    2012-12-18

    Chromium isotope fractionation is indicative of mass-transfer processes, such as reduction of Cr(VI) to Cr(III) during groundwater remediation. Laboratory experiments comparing batch and column treatment of Cr(VI) using organic carbon suggest that the associated isotope fractionation may be influenced by solute-transport mechanisms. These batch and column experiments were simulated using the reactive transport model MIN3P to further evaluate the effects of Cr reduction and transport on isotope fractionation under saturated flow conditions. Simulation of the batch experiment provided a good fit to the experimental data, where a fractionation factor (α₅₃) of 0.9965 was attributed to a single, dominant Cr(VI) removal mechanism. Calibration of the column simulations to the experimental results suggested the presence of a second, more rapid Cr(VI) removal mechanism with α₅₃ = 0.9992. Results from this study demonstrate that the interpretation of Cr isotope fractionation during reduction can be complex, particularly where multiple removal mechanisms are evident. Reactive transport modeling of Cr isotope fractionation can provide a quantitative assessment of the contaminant removal mechanisms, thus improving the application of Cr isotope measurements as a tool to track Cr(VI) migration and attenuation in groundwater.

  2. Central receiver solar thermal power system, Phase 1. CDRL item 2. Pilot plant preliminary design report. Volume VI. Electrical power generation and master control subsystems and balance of plant

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-10-01

    The requirements, performance, and subsystem configuration for both the Commercial and Pilot Plant electrical power generation subsystems (EPGS) and balance of plants are presented. The EPGS for both the Commercial Plant and Pilot Plant make use of conventional, proven equipment consistent with good power plant design practices in order to minimize risk and maximize reliability. The basic EPGS cycle selected is a regenerative cycle that uses a single automatic admission, condensing, tandem-compound double-flow turbine. Specifications, performance data, drawings, and schematics are included. (WHK)

  3. Screen-printed sensor for batch and flow injection potentiometric chromium(VI) monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Moreno, Raul A.; Gismera, M.J.; Sevilla, M.T.; Procopio, Jesus R. [Facultad de Ciencias, Universidad Autonoma de Madrid, Departamento de Quimica Analitica y Analisis Instrumental, Madrid (Spain)

    2010-05-15

    A disposable screen-printed electrode was designed and evaluated for direct detection of chromium(VI) in batch and flow analysis. The carbon screen-printed electrode was modified with a graphite-epoxy composite. The optimal graphite-epoxy matrix contains 37.5% graphite powder, 12.5% diphenylcarbohydrazide, a selective compound for chromium(VI), and 50% epoxy resin. The principal analytical parameters of the potentiometric response in batch and flow analysis were optimized and calculated. The screen-printed sensor exhibits a response time of 20 {+-} 1 s. In flow analysis, the analytical frequency of sampling is 70 injections per hour using 0.1 M NaNO{sub 3} solution at pH 3 as the carrier, a flow rate of 2.5 mL.min{sup -1}, and an injection sample volume of 0.50 mL. The sensor shows potentiometric responses that are very selective for chromium(VI) ions and optimal detection limits in both static mode (2.1 x 10{sup -7} M) and online analysis (9.4 x 10{sup -7} M). The disposable potentiometric sensor was employed to determine toxicity levels of chromium(VI) in mineral, tap, and river waters by flow-injection potentiometry and batch potentiometry. Chromium(VI) determination was also carried out with successful results in leachates from municipal solid waste landfills. (orig.)

  4. Reduction of chromium (VI) from aqueous solution by biomass of Cladosporium cladosporioides.

    Science.gov (United States)

    Garza-González, María Teresa; Ramírez-Vázquez, Jonathan Eduardo; García-Hernández, María de Los Ángeles; Cantú-Cárdenas, María Elena; Liñan-Montes, Adriana; Villarreal-Chiu, Juan Francisco

    2017-11-01

    The capacity of Cladosporium cladosporioides biomass for removal of Cr(VI) in aqueous solutions was evaluated. A 2 × 2 factorial experiment design was used to study the effects of pH and biomass doses. Lower pH values and larger biomass doses increased the capacity of C. cladosporioides biomass for removal of Cr(VI), reaching a reduction capacity of 492.85 mg g(-1), a significantly higher value compared to other biomass reported. Cr(VI) removal kinetic rates followed a pseudo-second order model, like other fungal biomass reported previously. The apparent adsorption process was described well by the Freundlich isothermal model. However, determination of total chromium indicated that adsorption of Cr(VI) was followed by a redox reaction that released proportional quantities of Cr(III) into the experimental supernatant, suggesting a parallel adsorption-reduction process. Comparison of Fourier transform infrared spectroscopy spectra of C. cladosporioides biomass before and after the reduction process demonstrated the involvement of positively charged amino groups in the Cr(VI) adsorption-reduction process.

  5. Validation of the Preverbal Visual Assessment (PreViAs) questionnaire.

    Science.gov (United States)

    García-Ormaechea, Inés; González, Inmaculada; Duplá, María; Andres, Eva; Pueyo, Victoria

    2014-10-01

    Visual cognitive integrative functions need to be evaluated by a behavioral assessment, which requires an experienced evaluator. The Preverbal Visual Assessment (PreViAs) questionnaire was designed to evaluate these functions, both in general pediatric population or in children with high risk of visual cognitive problems, through primary caregivers' answers. We aimed to validate the PreViAs questionnaire by comparing caregiver reports with results from a comprehensive clinical protocol. A total of 220 infants (visual development, as determined by the clinical protocol. Their primary caregivers completed the PreViAs questionnaire, which consists of 30 questions related to one or more visual domains: visual attention, visual communication, visual-motor coordination, and visual processing. Questionnaire answers were compared with results of behavioral assessments performed by three pediatric ophthalmologists. Results of the clinical protocol classified 128 infants as having normal visual maturation, and 92 as having abnormal visual maturation. The specificity of PreViAs questionnaire was >80%, and sensitivity was 64%-79%. More than 80% of the infants were correctly classified, and test-retest reliability exceeded 0.9 for all domains. The PreViAs questionnaire is useful to detect abnormal visual maturation in infants from birth to 24months of age. It improves the anamnesis process in infants at risk of visual dysfunctions. Copyright © 2014. Published by Elsevier Ireland Ltd.

  6. Aqueous U(VI) interaction with magnetite nanoparticles in a mixed flow reactor system: HR-XANES study

    Science.gov (United States)

    Pidchenko, I.; Heberling, F.; Kvashnina, KO; Finck, N.; Schild, D.; Bohnert, E.; Schäfer, T.; Rothe, J.; Geckeis, H.; Vitova, T.

    2016-05-01

    The redox variations and changes in local atomic environment of uranium (U) interacted with the magnetite nanoparticles were studied in a proof of principle experiment by the U L3 and M4 edges high energy resolution X-ray absorption near edge structure (HR-XANES) technique. We designed and applied a mixed flow reactor (MFR) set-up to maintain dynamic flow conditions during U-magnetite interactions. Formation of hydrolyzed, bi- and poly-nuclear U species were excluded by slow continuous injection of U(VI) (10-6 M) and pH control integrated in the MFR set-up. The applied U HR-XANES technique is more sensitive to minor changes in the U redox states and bonding compared to the conventional XANES method. Major U(VI) contribution in uranyl type of bonding is found in the magnetite nanoparticles after three days operation time of the MFR. Indications for shortening of the U-Oaxial bond length for the magnetite compared to the maghemite system are present too.

  7. Stability of uranium(VI) doped CSH phases in high saline water

    Energy Technology Data Exchange (ETDEWEB)

    Wolter, Jan-Martin; Schmeide, Katja [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

    2017-06-01

    To evaluate the long-term stability of U(VI) doped calcium silicate hydrate (CSH) phases at high saline conditions, leaching experiments with NaCl, NaCl/Na{sub 2}SO{sub 4} and NaCl/NaHCO{sub 3} containing solutions were performed. Time-resolved laser-induced fluorescence spectroscopy (TRLFS), infrared spectroscopy (IR) and X-ray powder diffraction (XRD) were applied to study the U(VI) binding onto the CSH phases and to get a deeper understanding of structural changes due to leaching. Results indicate that neither NaCl nor Na{sub 2}SO{sub 4} affect the structural stability of CSH phases and their retention potential for U(VI). However, carbonate containing solutions lead to a decomposition of CSH phases and thus, to a release of incorporated uranium.

  8. Bullying prevention in schools by targeting cognitions, emotions, and behavior: Evaluating the effectiveness of the REBE-ViSC program.

    Science.gov (United States)

    Trip, Simona; Bora, Carmen; Sipos-Gug, Sebastian; Tocai, Ioana; Gradinger, Petra; Yanagida, Takuya; Strohmeier, Dagmar

    2015-10-01

    The effectiveness of a class-based antibullying prevention program on cognitions, emotions, and behaviors was investigated. The program consists of a cognitive-behavioral (Rational Emotive Behavioral Education; REBE) and a behavioral (Viennese Social Competence; ViSC) component. The REBE program is based on rational emotive behavioral theory and contains 9 student lessons. The ViSC program is based on social learning theory and comprises 10 student lessons. The order of the programs was experimentally manipulated. The REBE-ViSC program was implemented in 5 schools (14 classes), the ViSC-REBE program was implemented in 3 schools (9 classes), and 3 schools (11 classes) served as an untreated control group. Data were collected during 1 school year at pretest, midpoint, and posttest. Emotions (overt and internalizing anger), cognitions (learning and entitlement), and behaviors (bullying perpetration and bullying victimization) were measured with self-assessments. To examine the effectiveness of the REBE-ViSC/ViSC-REBE program, multilevel growth models were applied (time points at Level 1, individuals at Level 2, and classes at Level 3). The analyses revealed that the program effects differed depending on the order of the programs. The REBE-ViSC condition was more effective in changing negative emotions than the ViSC-REBE condition; both experimental conditions were effective in reducing dysfunctional cognitions, whereas no behavioral change was found in the 2 experimental groups when compared with the control group. To improve program effectiveness regarding behavioral changes, a multilevel whole-school approach including a teacher component is recommended. (c) 2015 APA, all rights reserved).

  9. CIRCUIT-DESIGN SOLUTIONS AND INFORMATION SUPPORT OF CITY ELECTRIC NETWORKS IN THE CONDITIONS OF THE SMART GRID

    Directory of Open Access Journals (Sweden)

    M. I. Fursanov

    2017-01-01

    Full Text Available The structure, circuit-design solutions and information support of the city electric networks in the conditions of the SMART GRID have been analyzed. It is demonstrated that the new conditions of functioning of electric power engineering, increasing demands for its technological state and reliability in most countries determined the transition to a restructuring of electrical networks to be based on the SMART GRID (intelligent power networks innovative new structure. The definitions of the SMART GRID, its various attributes and characteristics in most developed countries including Belarus are presented. It is revealed that the existing and future circuit and constructive solutions that can automate the process of managing modes of urban electric networks under the SMART GRID conditions are manifold. At present, the most common in distribution networks are the sources of distributed generation (combustion turbines, wind turbines, photovoltaic installations, mini-hydro, etc.. The patterns and problems of information traceability of a traditional urban networks of the unified energy system of Belarus have been analyzed, and it is demonstrated that in the conditions of the SMART GRID most of the problems of the control mode that are characteristic for traditional distribution networks 6–10 kV and 0.38 kV, lose their relevance. Therefore, the present article presents and features the main directions of development of automatic control modes of the SMART GRID.

  10. The stability of four designer drugs: MDPV, mephedrone, BZP and TFMPP in three biological matrices under various storage conditions.

    Science.gov (United States)

    Johnson, Robert D; Botch-Jones, Sabra R

    2013-03-01

    The analysis of designer drugs, including those in the synthetic cathinone and piperazine classes, may be complicated by the poor stability of these compounds in biological specimens. The stability of four of these compounds was investigated: 3,4-methylenedioxypyrovalerone, 4-methyl-N-methylcathinone (mephedrone), N-benzylpiperazine and 1-[3-(trifluoromethyl)phenyl]piperazine. Compound stability was monitored in three different biological matrices when each matrix was stored under three different conditions. These matrices and conditions included human whole blood, human serum and human urine, each stored at -20, 4 and 22°C for a period of 14 days in the dark in a sealed glass container. Analysis by liquid chromatography-tandem mass spectrometry was performed on Day 1 to establish the initial concentration for each drug in each specimen type, and then the samples were divided into three parts for storage under the various conditions. Analysis was performed in triplicate on Days 2, 4, 7 and 14 for each specimen type under each storage condition and the results were compared to those obtained on Day 1. Following analysis of the data, it became clear that mephedrone was not stable, and that care must be taken following specimen receipt to ensure minimal degradation.

  11. System design and analysis of the trans-critical carbon-dioxide automotive air-conditioning system.

    Science.gov (United States)

    Mu, Jing-Yang; Chen, Jiang-Ping; Chen, Zhi-Jiu

    2003-01-01

    As an environmentally harmless and feasible alternate refrigerant, CO2 has attracted worldwide attention, especially in the area of automobile air-conditioning (AAC). The thermal property of CO2 and its trans-critical refrigeration cycle is very different from that of the traditional CFC or HCFC system. The detailed process of CO2 system thermal cycle design and optimization is described in this paper. System prototype and performance test bench were developed to analyze the performance of the CO2 AAC system.

  12. Flow Components in a NaK Test Loop Designed to Simulate Conditions in a Nuclear Surface Power Reactor

    Science.gov (United States)

    Polzin, Kurt A.; Godfroy, Thomas J.

    2008-01-01

    A test loop using NaK as the working fluid is presently in use to study material compatibility effects on various components that comprise a possible nuclear reactor design for use on the lunar surface. A DC electromagnetic (EM) pump has been designed and implemented as a means of actively controlling the NaK flow rate through the system and an EM flow sensor is employed to monitor the developed flow rate. These components allow for the matching of the flow rate conditions in test loops with those that would be found in a full-scale surface-power reactor. The design and operating characteristics of the EM pump and flow sensor are presented. In the EM pump, current is applied to a set of electrodes to produce a Lorentz body force in the fluid. A measurement of the induced voltage (back-EMF) in the flow sensor provides the means of monitoring flow rate. Both components are compact, employing high magnetic field strength neodymium magnets thermally coupled to a water-cooled housing. A vacuum gap limits the heat transferred from the high temperature NaK tube to the magnets and a magnetically-permeable material completes the magnetic circuit. The pump is designed to produce a pressure rise of 5 psi, and the flow sensor's predicted output is roughly 20 mV at the loop's nominal flow rate of 0.5 GPM.

  13. Methodical approaches in town-planning design of street circuits in the conditions of sustainable development of the city

    Science.gov (United States)

    Ivanova, Nina; Ganzha, Olga

    2017-10-01

    In article the technique of adoption of the design decision on placement of eco-friendly routes for the purpose of use is proved by steady transport, the technique of the choice of the optimal solution of development of local bicycle network of routes is offered and developed structural model of the choice of options of placement of cycle routes in system of street road system and recreational zones in the conditions of sustainable development of the city. The theoretical and practical experience of construction of cycle routes in Russia and abroad is generalized; the method of the analysis of hierarchies which allows to carry out the choice of the design decision taking into account different groups of factors is used; the structural model at the choice of options of placement of bicycle tracks on the example of linear structure of the coastal city is developed; experimental design in the territory of streets of Volgograd is executed. The offered structural model is used in development of design offers of construction of bicycle tracks for the streets of Volgograd providing to inhabitants and city visitors more attractive, healthy and cheap option of movement to place of work, training, rest and entertainments.

  14. Designing, Implementing, and Evaluating Mobile Health Technologies for Managing Chronic Conditions in Older Adults: A Scoping Review

    Science.gov (United States)

    Harris, Lauren; Ploeg, Jenny; Markle-Reid, Maureen; Valaitis, Ruta; Ibrahim, Sarah; Gafni, Amiram; Isaacs, Sandra

    2016-01-01

    Background The current landscape of a rapidly aging population accompanied by multiple chronic conditions presents numerous challenges to optimally support the complex needs of this group. Mobile health (mHealth) technologies have shown promise in supporting older persons to manage chronic conditions; however, there remains a dearth of evidence-informed guidance to develop such innovations. Objectives The purpose of this study was to conduct a scoping review of current practices and recommendations for designing, implementing, and evaluating mHealth technologies to support the management of chronic conditions in community-dwelling older adults. Methods A 5-stage scoping review methodology was used to map the relevant literature published between January 2005 and March 2015 as follows: (1) identified the research question, (2) identified relevant studies, (3) selected relevant studies for review, (4) charted data from selected literature, and (5) summarized and reported results. Electronic searches were conducted in 5 databases. In addition, hand searches of reference lists and a key journal were completed. Inclusion criteria were research and nonresearch papers focused on mHealth technologies designed for use by community-living older adults with at least one chronic condition, or health care providers or informal caregivers providing care in the home and community setting. Two reviewers independently identified articles for review and extracted data. Results We identified 42 articles that met the inclusion criteria. Of these, described innovations focused on older adults with specific chronic conditions (n=17), chronic conditions in general (n=6), or older adults in general or those receiving homecare services (n=18). Most of the mHealth solutions described were designed for use by both patients and health care providers or health care providers only. Thematic categories identified included the following: (1) practices and considerations when designing m

  15. Chromium isotope inventory of Cr(VI)-polluted groundwaters at four industrial sites in Central Europe

    Science.gov (United States)

    Novak, Martin; Martinkova, Eva; Chrastny, Vladislav; Stepanova, Marketa; Curik, Jan; Szurmanova, Zdenka; Cron, Marcel; Tylcer, Jiri; Sebek, Ondrej

    2016-04-01

    Chromium is one of the most toxic elements, especially in its dissolved Cr(VI) form. In the Czech Republic (Central Europe), massive contamination of groundwater has been reported at more than 200 industrial operations. Under suitable conditions, i.e., low Eh, and high availability of reductive agents, Cr(VI) in groundwater may be spontaneously reduced to solid, largely non-toxic Cr(III). This process is associated with a Cr isotope fractionation, with the residual liquid Cr(VI) becoming enriched in the heavier isotope 53Cr. At industrial operations that have been closed and/or where no further leakage of Cr(VI) occurs, the contaminated groundwater plume may be viewed as a closed system. At such sites, an increasing degree of Cr(VI) reduction should result in an increasing del53/52Cr value of the residual liquid. Here we present del53/52Cr systematics at four contaminated Czech sites, focusing on groundwaters. At two of the four sites (Zlate Hory, Loucna) we were also able to analyze the source of contamination. Chromium in the electroplating solutes was isotopically relatively light, with del53/52Cr values VI) reduction may proceed at Zlate Hory and Loucna, where del53/52Cr(VI) values in groundwater were on average higher than those of the contamination source. At these two sites, our Cr isotope data are not consistent with the existing estimates of the amount of dissolved and precipitated Cr: The pool size of solid Cr(III) in the soil was estimated at 6600 and 500 kg at Zlate Hory and Loucna, respectively. At the same time, the pool size of dissolved Cr(VI) was estimated at 50 and 1.2 kg at Zlate Hory and Loucna, respectively. It follows that, at both sites, less than 1 % of the entire Cr that had leaked into the aquifer an a liquid form remained in the liquid form. If, indeed, most solid Cr now present in the saturated zone had undergone anaerobic reduction, we would expect much higher del53/52Cr values of the residual liquid Cr(VI) than those actually observed

  16. Adsorption behavior of carboxylated cellulose nanocrystal—polyethyleneimine composite for removal of Cr(VI) ions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chao; Jin, Ru-Na; Ouyang, Xiao-kun, E-mail: xkouyang@zjou.edu.cn; Wang, Yang-Guang

    2017-06-30

    Highlights: • A carboxylated cellulose nanocrystal-polyethyleneimine composite (CCN-PEI) was prepared. • The as-prepared CCN-PEI was characterized by SEM, TEM, FT-IR, and XPS. • Results suggested that the reusable CCN-PEI could remove Cr(VI) from aqueous solutions with a high adsorption capacity. • The adsorption isotherm, thermodynamics, and kinetics of the adsorption process are also discussed. - Abstract: In this study, a composite adsorbent (CCN-PEI) composed of carboxylated cellulose nanocrystals (CCN) and polyethyleneimine (PEI) was prepared through an amidation reaction between the carboxyl groups of the CCN and the amine groups of the PEI. The adsorption performance of the CCN-PEI was tested by removing Cr(VI) ions from aqueous solutions. The physicochemical properties of the CCN and the Cr(VI) ion-loaded CCN-PEI were studied using scanning electron microscopy (SEM), transmission electron microscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. To investigate the adsorption kinetics of Cr(VI) ions onto this newly developed CCN-PEI, we performed experiments under different adsorption conditions, by varying the contact time, solution pH, initial Cr(VI) ion concentration, and adsorption temperature. The prepared CCN-PEI exhibited an encouraging uptake capacity of 358.42 mg × g{sup −1}. The adsorption process was fast: within the first 100 min, Cr(VI) ion adsorption onto the CCN-PEI was about 65%, and the adsorption equilibrium was reached within 250 min. Kinetics experiments indicated that the adsorption process could be described by a pseudo-second-order kinetic model. Furthermore, our adsorption equilibrium data fit the Langmuir isotherms well. The calculated thermodynamic parameters, such as the free energy change (ΔG = −2.93 kJ × mol{sup −1}), enthalpy change (ΔH = −5.69 kJ × mol{sup −1}), and entropy change (ΔS = −9.14 kJ × mol{sup −1}), indicate that the adsorption of Cr(VI) ions onto CCN

  17. Biosorption of Cr (VI) from aqueous solution by Rhizopus nigricans.

    Science.gov (United States)

    S Bai, R; Abraham, T E

    2001-08-01

    The study was aimed to quantify the Cr sorption ability of powdered biomass of Rhizopus nigricans at the best operating conditions. The influence of solution pH, agitation, Cr (VI) concentration, biomass dosage, contact time, biomass particle size and temperature were studied. The optimum pH for biosorption of Cr (VI) was found to be 2.0. Higher adsorption percentage was noted at lower initial concentrations of Cr ions, while the adsorption capacity of the biomass increased with increasing concentration of ions. Optimum biomass dosage was observed as 0.5% (w/v). More than 75% of the ions were removed within 30 min of contact and maximum removal was obtained after 8 h. Biomass particles of smaller size (90 microm) gave maximum adsorption (99.2%) at 100 mg/l concentration. The adsorption capacity increased with increase in temperature and agitation speed and the optimum were determined as 45 degrees C at 120 rpm. Freundlich and Langmuir isotherms were used to evaluate the data and the regression constants were derived. The adsorption rate constant values (Kad) were calculated for different initial concentration of Cr ions and the sorption was found to be higher at lower concentration (100 mg/l) of metal ion.

  18. Immobilization of Cr(Vi) as a contaminant from soil by iron compounds; Inmovilizacion de Cr(VI) como contaminante del suelo por compuestos de hierro

    Energy Technology Data Exchange (ETDEWEB)

    Marin A, M. de J.; Romero G, E. T. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Reyes G, L. R. [Universidad Autonoma del Estado de Hidalgo, Centro de Investigacion en Ciencias de la Tierra, Carretera Pachuca-Tulancingo Km. 4.5, Pachuca 42184, Hidalgo (Mexico)], e-mail: elizabeth.romero@inin.gob.mx

    2008-07-01

    The objective of this research was to determine the physicochemical and surface properties of Fe{sup 0} and FeS to select the appropriate radioactive material for use in the design of artificial barriers or walls and remove Cr (Vi). The physicochemical characterization was carried out of iron: Fe{sup 0} and FeS, using scanning electron microscopy of high vacuum, X-ray diffraction and thermal gravimetric analysis techniques. As for the characterization of the surface, was used to determine the surface area, point of zero charge, density of active sites and kinetics of moisture. We obtained a solution of Cr (Vi) by elution of deionized water on the pollution land of Buenavista, Guanajuato. The concentration of Cr (Vi) from a stock solution was 55.56 mg / L determined by UV-Vis spectrophotometry. Stripping or maximum immobilization of Cr (Vi) with Fe{sup 0} (material chosen by their physicochemical and surface properties) was 68.25% using Fe{sup 0}, at a concentration less than 0.1, ph equal to 3 and a contact time of 24 hours. (Author)

  19. Noget vi kan tro på

    DEFF Research Database (Denmark)

    Olsen, Jan Brødslev

    2016-01-01

    Situationen er alvorlig. Verden står over for enorme udfordringer med pres på naturressourcer, klima, befolkningsvækst, flygtninge og konflikter. Det er svært at se, hvordan disse problemer kan håndteres inden for den nuværende menneskelige bevidstheds rammer. Vi må derfor foretage et bevidstheds......Situationen er alvorlig. Verden står over for enorme udfordringer med pres på naturressourcer, klima, befolkningsvækst, flygtninge og konflikter. Det er svært at se, hvordan disse problemer kan håndteres inden for den nuværende menneskelige bevidstheds rammer. Vi må derfor foretage et...

  20. Hvad skal vi med Trump-satire?

    DEFF Research Database (Denmark)

    Møller, Mette

    2017-01-01

    Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til?......Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til?...

  1. CPE OF URANIUM (VI USING IONIC LIQUID

    Directory of Open Access Journals (Sweden)

    SANAA NAÏT-TAHAR

    2016-07-01

    Full Text Available Cloud point extraction (CPE was used to extract uranium (VI from an aqueous solution in acetate media. The methodology used is based on the formation of uranyl-ionic liquid (I complexes and uranyl-D2EHPA soluble in a micellar phase of non-ionic surfactant (Triton X-100. The uranium (VI complexes are then extracted into the surfactant-rich phase at ambient temperature. The ionic liquid (IL used as a chelating agent was synthesized and characterized in this study. It is composed of N-butyl N’-triethoxy methyl imidazolium cation and diethylhexylphosphate (D2EHPA-H as anion. The effect of the IL on the extraction efficiency was studied in presence and in absence of IL’s cation in acetate medium.

  2. Upscaling of U(VI) Desorption and Transport from Decimeter-Scale Heterogeneity to Plume-Scale Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Gary P. [U.S. Geological Survey, Menlo Park, CA (United States); Kohler, Matthias [U.S. Geological Survey, Menlo Park, CA (United States); Kannappan, Ramakrishnan [U.S. Geological Survey, Menlo Park, CA (United States); Briggs, Martin [U.S. Geological Survey, Menlo Park, CA (United States); Day-Lewis, Fred [U.S. Geological Survey, Menlo Park, CA (United States)

    2015-02-24

    Scientifically defensible predictions of field scale U(VI) transport in groundwater requires an understanding of key processes at multiple scales. These scales range from smaller than the sediment grain scale (less than 10 μm) to as large as the field scale which can extend over several kilometers. The key processes that need to be considered include both geochemical reactions in solution and at sediment surfaces as well as physical transport processes including advection, dispersion, and pore-scale diffusion. The research summarized in this report includes both experimental and modeling results in batch, column and tracer tests. The objectives of this research were to: (1) quantify the rates of U(VI) desorption from sediments acquired from a uranium contaminated aquifer in batch experiments;(2) quantify rates of U(VI) desorption in column experiments with variable chemical conditions, and(3) quantify nonreactive tracer and U(VI) transport in field tests.

  3. Corneal hysteresis in mucopolysaccharidosis I and VI.

    Science.gov (United States)

    Fahnehjelm, Kristina Teär; Chen, Enping; Winiarski, Jacek

    2012-08-01

    High intraocular pressure (IOP) and glaucoma are often suspected in patients with mucopolysaccharidosis (MPS). To determine corneal hysteresis (CH) and IOP in children with mucopolysaccharidosis I-Hurler (MPS I-H) and MPS VI. Clinical measurements with ocular response analyzer (ORA). In seven patients, five with MPS I-H treated with stem cell transplantation (SCT), and two with MPS VI, one treated with SCT and the other with enzyme therapy, the IOP was examined with ORA. Ocular response analyzer measurements were made at a median age of 8.7 years in the patients with MPS I-H and at a median age of 9.3 years in the patients with MPS VI. Earlier measurements had raised suspicion of high IOP in one patient. The ORA showed an increased CH and a falsely high IOP values in all 14 eyes. The recalculated IOPs were normal in all 14 eyes. Mild to severe corneal opacities were present in all 14 eyes. Optic disc areas, borders and cupping were clinically normal in the 12 of 14 eyes that were possible to examine. Severe corneal opacities hampered optic disc evaluation in the older patient with MPS VI. Three eyes in two patients had normal thickness of the retinal nerve fibre layer measured with scanning laser polarimetry with corneal compensation (GDx VCC). No patient was diagnosed or treated for glaucoma. The IOPs are often falsely high because of an increased resistance of the cornea and correlate to the extent of corneal clouding. In this small, cross-sectional study, it appears that corneal resistance is directly correlated with corneal clouding, although a longitudinal study that evaluates resistance as the cornea clears with treatment would provide more direct evidence that corneal deposits are directly related to resistance. A correct measured IOP can avoid unnecessary medical or surgical hypotensive treatment. © 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.

  4. Prospek pengembangan industri perkulitan pada pelita VI

    Directory of Open Access Journals (Sweden)

    D Karyadi

    1995-06-01

    Full Text Available The leather industry is one of the strong competitive industry, as it comes from renewable natural resources. Therefore, the leather industry has good prospect to develop at the Pelita VI to be the industrial products export competitive. To develop leather industry and leather products should be given closed attention and well managed, especially concerning raw material supply, quality and leather waste treatment.

  5. Design and experimental study of a mixed energy recovery system, heat pipes and indirect evaporative equipment for air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Francisco Javier Rey; Gomez, Eloy Velasco; Diez, Fernando Varela; Martin, Ruth Herrero [Valladolid Univ., Dept. of Energy Engineering aand Fluid Mechanics, Valladolid (Spain); Plasencia, Mario Antonio Alvarez-Guerra [Cienfuegos Univ., Faculty of Computer Engineering, Cienfuegos (Spain)

    2003-11-01

    Current difficulties surrounding air conditioning systems involve an increase in input air aimed at improving indoor air quality (IAQ), the financial costs arising from energy consumption and external environmental impact, linked to the greenhouse effect (GWP) and the destruction of the ozone layer (ODP). One alternative technique which offers an adequate combination of IAQ and acceptable energy saving is the introduction of energy recovery systems using air extracted from air-conditioned premises. We have designed a mixed air-energy recovery system, consisting of two heat pipes and indirect evaporative recuperators. The experimental set-up used is described and the proposed energy recovery system is characterised. A staggered set-up has been chosen for the input air pipe and a parallel one for the extracted air for variable recirculation. By means of the trace gas method and photoacoustic spectroscopy (PAS) the amount of exfiltrated flow in the installation is measured. The energy characterisation of the mixed energy recovery system was performed by means of the experimental design technique. An analysis was carried out of the influence of factors such as temperature, flow, relative humidity, water flow, etc. on the basic characteristics defined by the mixed system: heat flow, heat efficiency and COP. (Author)

  6. Compositional Modeling for Optimum Design of Water-Alternating CO2-LPG EOR under Complicated Wettability Conditions

    Directory of Open Access Journals (Sweden)

    Jinhyung Cho

    2015-01-01

    Full Text Available The addition of LPG to the CO2 stream leads to minimum miscible pressure (MMP reduction that causes more oil swelling and interfacial tension reduction compared to CO2 EOR, resulting in improved oil recovery. Numerical study based on compositional simulation has been performed to examine the injectivity efficiency and transport behavior of water-alternating CO2-LPG EOR. Based on oil, CO2, and LPG prices, optimum LPG concentration and composition were designed for different wettability conditions. Results from this study indicate how injected LPG mole fraction and butane content in LPG affect lowering of interfacial tension. Interfacial tension reduction by supplement of LPG components leads to miscible condition causing more enhanced oil recovery. The maximum enhancement of oil recovery for oil-wet reservoir is 50% which is greater than 22% for water-wet reservoir. According to the result of net present value (NPV analysis at designated oil, CO2, propane, and butane prices, the optimal injected LPG mole fraction and composition exist for maximum NPV. At the case of maximum NPV for oil-wet reservoir, the LPG fraction is about 25% in which compositions of propane and butane are 37% and 63%, respectively. For water-wet reservoir, the LPG fraction is 20% and compositions of propane and butane are 0% and 100%.

  7. Selective Reduction of Cr(VI in Chromium, Copper and Arsenic (CCA Mixed Waste Streams Using UV/TiO2 Photocatalysis

    Directory of Open Access Journals (Sweden)

    Shan Zheng

    2015-02-01

    Full Text Available The highly toxic Cr(VI is a critical component in the Chromated Copper Arsenate (CCA formulations extensively employed as wood preservatives. Remediation of CCA mixed waste and discarded treated wood products is a significant challenge. We demonstrate that UV/TiO2 photocatalysis effectively reduces Cr(VI to less toxic Cr(III in the presence of arsenate, As(V, and copper, Cu(II. The rapid conversion of Cr(VI to Cr(III during UV/TiO2 photocatalysis occurs over a range of concentrations, solution pH and at different Cr:As:Cu ratios. The reduction follows pseudo-first order kinetics and increases with decreasing solution pH. Saturation of the reaction solution with argon during UV/TiO2 photocatalysis had no significant effect on the Cr(VI reduction demonstrating the reduction of Cr(VI is independent of dissolved oxygen. Reduction of Cu(II and As(V does not occur under the photocatalytic conditions employed herein and the presence of these two in the tertiary mixtures had a minimal effect on Cr(VI reduction. The Cr(VI reduction was however, significantly enhanced by the addition of formic acid, which can act as a hole scavenger and enhance the reduction processes initiated by the conduction band electron. Our results demonstrate UV/TiO2 photocatalysis effectively reduces Cr(VI in mixed waste streams under a variety of conditions.

  8. Selective reduction of Cr(VI) in chromium, copper and arsenic (CCA) mixed waste streams using UV/TiO2 photocatalysis.

    Science.gov (United States)

    Zheng, Shan; Jiang, Wenjun; Rashid, Mamun; Cai, Yong; Dionysiou, Dionysios D; O'Shea, Kevin E

    2015-02-03

    The highly toxic Cr(VI) is a critical component in the Chromated Copper Arsenate (CCA) formulations extensively employed as wood preservatives. Remediation of CCA mixed waste and discarded treated wood products is a significant challenge. We demonstrate that UV/TiO2 photocatalysis effectively reduces Cr(VI) to less toxic Cr(III) in the presence of arsenate, As(V), and copper, Cu(II). The rapid conversion of Cr(VI) to Cr(III) during UV/TiO2 photocatalysis occurs over a range of concentrations, solution pH and at different Cr:As:Cu ratios. The reduction follows pseudo-first order kinetics and increases with decreasing solution pH. Saturation of the reaction solution with argon during UV/TiO2 photocatalysis had no significant effect on the Cr(VI) reduction demonstrating the reduction of Cr(VI) is independent of dissolved oxygen. Reduction of Cu(II) and As(V) does not occur under the photocatalytic conditions employed herein and the presence of these two in the tertiary mixtures had a minimal effect on Cr(VI) reduction. The Cr(VI) reduction was however, significantly enhanced by the addition of formic acid, which can act as a hole scavenger and enhance the reduction processes initiated by the conduction band electron. Our results demonstrate UV/TiO2 photocatalysis effectively reduces Cr(VI) in mixed waste streams under a variety of conditions.

  9. Iterative Design and Usability Testing of the iMHere System for Managing Chronic Conditions and Disability

    Directory of Open Access Journals (Sweden)

    Andrea D. Fairman

    2016-07-01

    Full Text Available A novel mobile health platform, Interactive Mobile Health and Rehabilitation (iMHere, is being developed to support wellness and self-management among people with chronic disabilities. The iMHere system currently includes a smartphone app with six modules for use by persons with disabilities and a web portal for use by medical and rehabilitation professionals or other support personnel. Our initial clinical research applying use of this system provides insight into the feasibility of employing iMHere in the development of self-management skills in young adults (ages 18-40 years with spina bifida (Dicianno, Fairman, McCue, Parmanto, Yih, et al., 2015. This article is focused on describing the iterative design of the iMHere system including usability testing of both the app modules and clinician portal. Our pilot population of persons with spina bifida fostered the creation of a system appropriate for people with a wide variety of functional abilities and needs. As a result, the system is appropriate for use by persons with various disabilities and chronic conditions, not only spina bifida. In addition, the diversity of professionals and support personnel involved in the care of persons with spina bifida (SB also enabled the design and implementation of the iMHere system to meet the needs of an interdisciplinary team of providers who treat various conditions. The iMHere system has the potential to foster communication and collaboration among members of an interdisciplinary healthcare team, including individuals with chronic conditions and disabilities, for client-centered approach to support self-management skills.

  10. Sphingosine-1-phosphate promotes the differentiation of human umbilical cord mesenchymal stem cells into cardiomyocytes under the designated culturing conditions

    Directory of Open Access Journals (Sweden)

    Zhang Henggui

    2011-06-01

    Full Text Available Abstract Background It is of growing interest to develop novel approaches to initiate differentiation of mesenchymal stem cells (MSCs into cardiomyocytes. The purpose of this investigation was to determine if Sphingosine-1-phosphate (S1P, a native circulating bioactive lipid metabolite, plays a role in differentiation of human umbilical cord mesenchymal stem cells (HUMSCs into cardiomyocytes. We also developed an engineered cell sheet from these HUMSCs derived cardiomyocytes by using a temperature-responsive polymer, poly(N-isopropylacrylamide (PIPAAm cell sheet technology. Methods Cardiomyogenic differentiation of HUMSCs was performed by culturing these cells with either designated cardiomyocytes conditioned medium (CMCM alone, or with 1 μM S1P; or DMEM with 10% FBS + 1 μM S1P. Cardiomyogenic differentiation was determined by immunocytochemical analysis of expression of cardiomyocyte markers and patch clamping recording of the action potential. Results A cardiomyocyte-like morphology and the expression of α-actinin and myosin heavy chain (MHC proteins can be observed in both CMCM culturing or CMCM+S1P culturing groups after 5 days' culturing, however, only the cells in CMCM+S1P culture condition present cardiomyocyte-like action potential and voltage gated currents. A new approach was used to form PIPAAm based temperature-responsive culture surfaces and this successfully produced cell sheets from HUMSCs derived cardiomyocytes. Conclusions This study for the first time demonstrates that S1P potentiates differentiation of HUMSCs towards functional cardiomyocytes under the designated culture conditions. Our engineered cell sheets may provide a potential for clinically applicable myocardial tissues should promote cardiac tissue engineering research.

  11. Impaired Behavior Regulation under Conditions of Concurrent Variable Schedules of Reinforcement in Children with ADHD

    Science.gov (United States)

    Taylor, David; Lincoln, Alan J.; Foster, Sharon L.

    2010-01-01

    Objective: To bridge theory of response inhibition and learning in children with ADHD. Method: Thirty ADHD and 30 non-ADHD children (ages 9-12) were compared under concurrent variable interval (VI-15 sec., VI-30 sec. and VI- 45 sec.) reinforcement schedules that required the child to switch between the three schedules under conditions of…

  12. Cr(VI) removal from aqueous systems using pyrite as the reducing agent: batch, spectroscopic and column experiments.

    Science.gov (United States)

    Kantar, Cetin; Ari, Cihan; Keskin, Selda; Dogaroglu, Zeynep Gorkem; Karadeniz, Aykut; Alten, Akin

    2015-03-01

    Laboratory batch and column experiments, in conjunction with geochemical calculations and spectroscopic analysis, were performed to better understand reaction mechanisms and kinetics associated with Cr(VI) removal from aqueous systems using pyrite as the reactive material under both static and dynamic flow conditions similar to those observed in in situ permeable reactive barriers (PRBs). The X-ray photoelectron spectroscopy (XPS) and geochemical calculations suggest that the Cr(VI) removal by pyrite occurred due to the reduction of Cr(VI) to Cr(III), coupled with the oxidation of Fe(II) to Fe(III) and S2(2-) to SO4(2-) at the pyrite surface. Zeta potential measurements indicate that although the pyrite surface was negatively charged under a wide pH range in the absence of Cr(VI), it behaved more like a "metal oxide" surface with the surface potential shifting from positive to negative values at pH values >pH 6 in the presence of Cr(VI). Batch experiments show that increasing solution pH led to a significant decrease in Cr(VI) removal. The decrease in Cr(VI) removal at high Cr(VI) concentrations and pH values can be explained through the precipitation of sparingly soluble Cr(OH)(3(s)), Fe(OH)(3(s)) and Fe(III)-Cr(III) (oxy) hydroxides onto pyrite surface which may, then, lead to surface passivation for further Cr(VI) reduction. Batch results also suggest that the reaction kinetics follow a first order model with rate constants decreasing with increasing solution pH, indicating proton consumption during Cr(VI) reduction by pyrite. Column experiments indicate that nearly 100% of total Fe in the column effluent was in the form of Fe(II) species with a [SO4(2-)]/[Fe(2+)] stoichiometric ratio of 2.04, indicating that the reduction of Cr(VI) by pyrite produced about 2 mol of sulfate per mole of Fe (II) release under excess surface sites relative to Cr(VI) concentration. Column experiments provide further evidence on the accumulation of oxidation products which

  13. Cr(VI) removal from aqueous systems using pyrite as the reducing agent: Batch, spectroscopic and column experiments

    Science.gov (United States)

    Kantar, Cetin; Ari, Cihan; Keskin, Selda; Dogaroglu, Zeynep Gorkem; Karadeniz, Aykut; Alten, Akin

    2015-03-01

    Laboratory batch and column experiments, in conjunction with geochemical calculations and spectroscopic analysis, were performed to better understand reaction mechanisms and kinetics associated with Cr(VI) removal from aqueous systems using pyrite as the reactive material under both static and dynamic flow conditions similar to those observed in in situ permeable reactive barriers (PRBs). The X-ray photoelectron spectroscopy (XPS) and geochemical calculations suggest that the Cr(VI) removal by pyrite occurred due to the reduction of Cr(VI) to Cr(III), coupled with the oxidation of Fe(II) to Fe(III) and S22 - to SO42 - at the pyrite surface. Zeta potential measurements indicate that although the pyrite surface was negatively charged under a wide pH range in the absence of Cr(VI), it behaved more like a "metal oxide" surface with the surface potential shifting from positive to negative values at pH values > pH 6 in the presence of Cr(VI). Batch experiments show that increasing solution pH led to a significant decrease in Cr(VI) removal. The decrease in Cr(VI) removal at high Cr(VI) concentrations and pH values can be explained through the precipitation of sparingly soluble Cr(OH)3(s), Fe(OH)3(s) and Fe(III)-Cr(III) (oxy) hydroxides onto pyrite surface which may, then, lead to surface passivation for further Cr(VI) reduction. Batch results also suggest that the reaction kinetics follow a first order model with rate constants decreasing with increasing solution pH, indicating proton consumption during Cr(VI) reduction by pyrite. Column experiments indicate that nearly 100% of total Fe in the column effluent was in the form of Fe(II) species with a [SO42 -]/[Fe2 +] stoichiometric ratio of 2.04, indicating that the reduction of Cr(VI) by pyrite produced about 2 mol of sulfate per mole of Fe (II) release under excess surface sites relative to Cr(VI) concentration. Column experiments provide further evidence on the accumulation of oxidation products which consequently led

  14. Modacrylic anion-exchange fibers for Cr(VI) removal from chromium-plating rinse water in batch and flow-through column experiments.

    Science.gov (United States)

    Lee, Seung-Chan; Kang, Jin-Kyu; Sim, Eun-Hye; Choi, Nag-Choul; Kim, Song-Bae

    2017-11-10

    The aim of this study was to investigate Cr(VI) removal from chromium-plating rinse water using modacrylic anion-exchange fibers (KaracaronTM KC31). Batch experiments were performed with synthetic Cr(VI) solutions to characterize the KC31 fibers in Cr(VI) removal. Cr(VI) removal by the fibers was affected by solution pH; the Cr(VI) removal capacity was the highest at pH 2 and decreased gradually with a pH increase from 2 to 12. In regeneration and reuse experiments, the Cr(VI) removal capacity remained above 37.0 mg g(-1) over five adsorption-desorption cycles, demonstrating that the fibers could be successfully regenerated with NaCl solution and reused. The maximum Cr(VI) removal capacity was determined to be 250.3 mg g(-1) from the Langmuir model. In Fourier-transform infrared spectra, a Cr = O peak newly appeared at 897 cm(-1) after Cr(VI) removal, whereas a Cr-O peak was detected at 772 cm(-1) due to the association of Cr(VI) ions with ion-exchange sites. X-ray photoelectron spectroscopy analyses demonstrated that Cr(VI) was partially reduced to Cr(III) after the ion exchange on the surfaces of the fibers. Batch experiments with chromium-plating rinse water (Cr(VI) concentration = 1178.8 mg L(-1)) showed that the fibers had a Cr(VI) removal capacity of 28.1-186.4 mg g(-1) under the given conditions (fiber dose = 1-10 g L(-1)). Column experiments (column length = 10 cm, inner diameter = 2.5 cm) were conducted to examine Cr(VI) removal from chromium-plating rinse water by the fibers under flow-through column conditions. The Cr(VI) removal capacities for the fibers at flow rates of 0.5 and 1.0 mL min(-1) were 214.8 and 171.5 mg g(-1), respectively. This study demonstrates that KC31 fibers are effective in the removal of Cr(VI) ions from chromium-plating rinse water.

  15. Optimization of the condition for adsorption of gallic acid by Aspergillus oryzae mycelia using Box-Behnken design.

    Science.gov (United States)

    Zhang, Zhicai; Pang, Qiaoxia; Li, Min; Zheng, Huihua; Chen, Hui; Chen, Keping

    2015-01-01

    Fresh biomass of Aspergillus oryzae (A. oryzae) CGMCC5992 can effectively remove gallic acid from aqueous solution. To improve the removal rate of gallic acid, this study first identified the important factors affecting the removal rate of gallic acid with univariate analysis, and then used four-factor and three-level Box-Behnken design (BBD) with the removal rate of gallic acid as response value, to obtain the optimum conditions for the removal of gallic acid as follows: 6.95 h treatment time, pH 3.70, 7.07 g/L mycelium volume, and 120.64 mg/L initial concentration of gallic acid. Under such optimized condition, the removal rate of gallic acid approached 99.21 %. HPLC-MS analysis proved that the gallic acid in aqueous solution was completely removed by A. oryzae, rather than being metabolized into its derivatives. Scanning electron microscopy (SEM) indicated that the biomass morphology and surface structure of A. oryzae changed after the adsorption of gallic acid. Thus, the present study has provided an optimal condition for A. oryzae removal of gallic acid in water.

  16. 20 CFR 662.430 - Under what conditions may One-Stop operators designated to operate in a One-Stop delivery system...

    Science.gov (United States)

    2010-04-01

    ... designated to operate in a One-Stop delivery system established prior to the enactment of WIA be designated... DESCRIPTION OF THE ONE-STOP SYSTEM UNDER TITLE I OF THE WORKFORCE INVESTMENT ACT One-Stop Operators § 662.430 Under what conditions may One-Stop operators designated to operate in a One-Stop delivery system...

  17. Mucopolissacaridose tipo VI: relato de caso

    Directory of Open Access Journals (Sweden)

    Lais Orosco Bialon Santana

    2014-10-01

    Full Text Available Introdução: As mucopolissacaridoses são erros inatos do metabolismo de depósito lisossomal subclassificadas segundo a enzima deficiente. A arilsulfatase B (ARSB, responsável por degradar os glicosaminoglicanos (GAGs, que atuam no tecido conjuntivo, é deficiente na mucopolissacaridose tipo VI (MP VI. A MP VI tem clínica variável, sem anormalidades ao nascimento, evidenciando-se progressivamente ao acúmulo de GAGs. O diagnóstico se faz pela redução da atividade da ARSB ou da mutação genética. A principal causa de óbito é insuficiência cardíaca, ocorrendo na segunda ou terceira década de vida. Relato de Caso: Masculino, 4 anos, portador de MP VI, há 3 dias com febre e sinais flogísticos em sítio de acesso central, colocado para reposição enzimática, com flutuação e saída de material purulento. Ultrassom evidenciou coleção laminar e borramento de planos gordurosos. Ecocardiograma demonstra hipertensão pulmonar discreta decorrente de prolapso valvar mitral com refluxo discreto, além de endocardite da valva mitral. Optou-se por retirada cirúrgica do dispositivo e administração de vancomicina e amicacina. Durante internação, evoluiu bem, sem complicações pós operatórias. Conclusão: A MP VI têm inteligência preservada, baixa estatura e alterações osteomusculares, como no caso relatado. Não há correlação entre a gravidade clínica e a atividade residual enzimática. Dificuldade respiratória pode levar a hipóxia crônica, hipertensão pulmonar e insuficiência cardíaca congestiva. Das alterações cardíacas, encontramos valvulopatias, insuficiência cardíaca e hipertensão pulmonar, observadas no caso. O tratamento se faz com transplante de células-tronco hematopoiéticas e terapia de reposição enzimática.

  18. Integrating legacy soil information in a Digital Soil Mapping approach based on a modified conditioned Latin Hypercube Sampling design

    Science.gov (United States)

    Stumpf, Felix; Schmidt, Karsten; Behrens, Thorsten; Schoenbrodt-Stitt, Sarah; Scholten, Thomas

    2014-05-01

    One crucial component of a Digital Soil Mapping (DSM) framework is outlined by geo-referenced soil observations. Nevertheless, highly informative legacy soil information, acquired by traditional soil surveys, is often neglected due to lacking accordance with specific statistical DSM designs. The focus of this study is to integrate legacy data into a state-of-the-art DSM approach, based on a modified conditioned Latin Hypercube Sampling (cLHS) design and Random Forest. Furthermore, by means of the cLHS modification the scope of actually unique cLHS sampling locations is widened in order to compensate limited accessability in the field. As well, the maximally stratified cLHS design is not diluted by the modification. Exemplarily the target variables of the modelling are represented by sand and clay fractions. The study site is a small mountainous hydrological catchment of 4.2 km² in the reservoir of the Three Gorges Dam in Central China. The modification is accomplished by demarcating the histogram borders of each cLHS stratum, which are based on the multivariate cLHS feature space. Thereby, all potential sample locations per stratum are identified. This provides a possibility to integrate legacy data samples that match one of the newly created sample locations, and flexibility with respect to field accessibility. Consequently, six legacy data samples, taken from a total sample size of n = 30 were integrated into the sampling design and for all strata several potential sample locations are identified. The comparability of the modified and standard cLHS data sets is approved by (i) identifying their feature space coverage with respect to the cLHS stratifying variables, and (ii) by assessing the Random Forest accuracy estimates.

  19. Modeling and optimization of energy generation and storage systems for thermal conditioning of buildings targeting conceptual building design

    Energy Technology Data Exchange (ETDEWEB)

    Grahovac, Milica

    2012-11-29

    The thermal conditioning systems are responsible for almost half of the energy consump-tion by commercial buildings. In many European countries and in the USA, buildings account for around 40% of primary energy consumption and it is therefore vital to explore further ways to reduce the HVAC (Heating, Ventilation and Air Conditioning) system energy consumption. This thesis investigates the relationship between the energy genera-tion and storage systems for thermal conditioning of buildings (shorter: primary HVAC systems) and the conceptual building design. Certain building design decisions irreversibly influence a building's energy performance and, conversely, many generation and storage components impose restrictions on building design and, by their nature, cannot be introduced at a later design stage. The objective is, firstly, to develop a method to quantify this influence, in terms of primary HVAC system dimensions, its cost, emissions and energy consumption and, secondly, to enable the use of the developed method by architects during the conceptual design. In order to account for the non-stationary effects of the intermittent renewable energy sources (RES), thermal storage and for the component part load efficiencies, a time domain system simulation is required. An abstract system simulation method is proposed based on seven pre-configured primary HVAC system models, including components such as boil-ers, chillers and cooling towers, thermal storage, solar thermal collectors, and photovoltaic modules. A control strategy is developed for each of the models and their annual quasi-stationary simulation is performed. The performance profiles obtained are then used to calculate the energy consumption, carbon emissions and costs. The annuity method has been employed to calculate the cost. Optimization is used to automatically size the HVAC systems, based on their simulation performance. Its purpose is to identify the system component dimensions that provide

  20. Biomineralization of U(VI) phosphate promoted by microbially-mediated phytate hydrolysis in contaminated soils

    Science.gov (United States)

    Salome, Kathleen R.; Beazley, Melanie J.; Webb, Samuel M.; Sobecky, Patricia A.; Taillefert, Martial

    2017-01-01

    The bioreduction of uranium may immobilize a significant fraction of this toxic contaminant in reduced environments at circumneutral pH. In oxic and low pH environments, however, the low solubility of U(VI)-phosphate minerals also makes them good candidates for the immobilization of U(VI) in the solid phase. As inorganic phosphate is generally scarce in soils, the biomineralization of U(VI)-phosphate minerals via microbially-mediated organophosphate hydrolysis may represent the main immobilization process of uranium in these environments. In this study, contaminated sediments were incubated aerobically in two pH conditions to examine whether phytate, a naturally-occurring and abundant organophosphate in soils, could represent a potential phosphorous source to promote U(VI)-phosphate biomineralization by natural microbial communities. While phytate hydrolysis was not evident at pH 7.0, nearly complete hydrolysis was observed both with and without electron donor at pH 5.5, suggesting indigenous microorganisms express acidic phytases in these sediments. While the rate of hydrolysis of phytate generally increased in the presence of uranium, the net rate of inorganic phosphate production in solution was decreased and inositol phosphate intermediates were generated in contrast to similar incubations conducted without uranium. These findings suggest uranium stress enhanced the phytate-metabolism of the microbial community, while simultaneously inhibiting phosphatase production and/or activity by the indigenous population. Finally, phytate hydrolysis drastically decreased uranium solubility, likely due to formation of ternary sorption complexes, U(VI)-phytate precipitates, and U(VI)-phosphate minerals. Overall, the results of this study provide evidence for the ability of natural microbial communities to liberate phosphate from phytate in acidic sediments, possibly as a detoxification mechanism, and demonstrate the potential utility of phytate-promoted uranium

  1. Uranium(VI) Binding Forms in Selected Human Body Fluids: Thermodynamic Calculations versus Spectroscopic Measurements.

    Science.gov (United States)

    Osman, Alfatih A A; Geipel, Gerhard; Barkleit, Astrid; Bernhard, Gert

    2015-02-16

    Human exposure to uranium increasingly becomes a subject of interest in many scientific disciplines such as environmental medicine, toxicology, and radiation protection. Knowledge about uranium chemical binding forms(speciation) in human body fluids can be of great importance to understand not only its biokinetics but also its relevance in risk assessment and in designing decorporation therapy in the case of accidental overexposure. In this study, thermodynamic calculations of uranium speciation in relevant simulated and original body fluids were compared with spectroscopic data after ex-situ uranium addition. For the first time, experimental data on U(VI) speciation in body fluids (saliva, sweat, urine) was obtained by means of cryogenic time-resolved laser-induced fluorescence spectroscopy (cryo-TRLFS) at 153 K. By using the time dependency of fluorescence decay and the band positions of the emission spectra, various uranyl complexes were demonstrated in the studied samples. The variations of the body fluids in terms of chemical composition, pH, and ionic strength resulted in different binding forms of U(VI). The speciation of U(VI) in saliva and in urine was affected by the presence of bioorganic ligands, whereas in sweat, the distribution depends mainly on inorganic ligands. We also elucidated the role of biological buffers, i.e., phosphate (H(2)PO(4−)/HPO(4)(2−)) on U(VI) distribution, and the system Ca(2+)/UO(2)(2+)/PO(4)(3−) was discussed in detail in both saliva and urine. The theoretical speciation calculations of the main U(VI) species in the investigated body fluids were significantly consistent with the spectroscopic data. Laser fluorescence spectroscopy showed success and reliability for direct determination of U(VI) in such biological matrices with the possibility for further improvement.

  2. High efficiency green LEDs using II-VI color converters

    Science.gov (United States)

    Miller, Thomas J.; Haase, Michael A.; Sun, Xiaoguang; Hao, Bing; Zhang, Junying; Smith, Terry L.; Ballen, Todd; Xie, Junqing; Barnes, Amy S.; Kecman, Fedja; Yang, Joseph; Thielen, James; Leatherdale, Catherine A.; Wirth, Ralph; Biebersdorf, Andreas; Engl, Karl; Groetsch, Stefan

    2010-02-01

    II-VI semiconductors can exhibit strong photoluminescence throughout the visible spectrum and are excellent candidates for filling the so-called "green gap". We report on the performance of green color-converted LEDs fabricated by bonding CdMgZnSe multiple quantum well structures to high-efficiency blue-emitting GaInN LEDs. A device efficacy of 181 lm/W at 537 nm (dominant) is measured under room temperature, 350 mA/mm2 quasi-cw conditions, more than twice as efficient as typical commercial green LEDs today. The thermal roll-off is shown to be comparable to that of typical green GaInN LEDs. Finally, the implications of the availability of high-efficiency, narrow-band, green and yellow emitters in display applications will be discussed.

  3. Guide for Operational Configuration Management Program including the adjunct programs of design reconstitution and material condition and aging management. Part 2

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    This standard presents program criteria and implementation guidance for an operational configuration management program for DOE nuclear and non-nuclear facilities. This Part 2 includes chapters on implementation guidance for operational configuration management, implementation guidance for design reconstitution, and implementation guidance for material condition and aging management. Appendices are included on design control, examples of design information, conduct of walkdowns, and content of design information summaries.

  4. Design and methods in a survey of living conditions in the Arctic – the SLiCA study

    Directory of Open Access Journals (Sweden)

    Bent-Martin Eliassen

    2012-03-01

    Full Text Available Objectives: The main objective of this study is to describe the methods and design of the survey of living conditions in the Arctic (SLiCA, relevant participation rates and the distribution of participants, as applicable to the survey data in Alaska, Greenland and Norway. This article briefly addresses possible selection bias in the data and also the ways to tackle it in future studies. Study design: Population-based cross-sectional survey. Methods: Indigenous individuals aged 16 years and older, living in Greenland, Alaska and in traditional settlement areas in Norway, were invited to participate. Random sampling methods were applied in Alaska and Greenland, while non-probability sampling methods were applied in Norway. Data were collected in 3 periods: in Alaska, from January 2002 to February 2003; in Greenland, from December 2003 to August 2006; and in Norway, in 2003 and from June 2006 to June 2008. The principal method in SLiCA was standardised face-to-face interviews using a questionnaire. Results: A total of 663, 1,197 and 445 individuals were interviewed in Alaska, Greenland and Norway, respectively. Very high overall participation rates of 83% were obtained in Greenland and Alaska, while a more conventional rate of 57% was achieved in Norway. A predominance of female respondents was obtained in Alaska. Overall, the Sami cohort is older than the cohorts from Greenland and Alaska. Conclusions: Preliminary assessments suggest that selection bias in the Sami sample is plausible but not a major threat. Few or no threats to validity are detected in the data from Alaska and Greenland. Despite different sampling and recruitment methods, and sociocultural differences, a unique database has been generated, which shall be used to explore relationships between health and other living conditions variables.

  5. Can iron oxides remove Cr(VI) from drinking water at sub-ppb levels?

    Science.gov (United States)

    Kaprara, Efthymia; Simeonidis, Konstantinos; Samaras, Petros; Zouboulis, Anastasios; Mitrakas, Manassis

    2013-04-01

    show any promising results. However, under rapid small scale column conditions, magnetite presented an ability to decrease residual chromium concentration at sub-ppb levels for a satisfactory period of time. Additionally, in regard to the current regulation limit for chromium in drinking water (50μg/L), magnetite's adsorption capacity was greater than 5mg Cr(VI)/gads. Such results encourage further investigation regarding the parameters influencing magnetite's ability to absorb Cr(VI) i.e. the method of its synthesis and particle size. The research Project is co-financed by the European Union - European Social Fund (ESF) & National Sources, in the framework of the program "THALIS" of the "Operational Program Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) 2007-2013.

  6. Optimization of the marinating conditions of cassava fish (Pseudotolithus sp.) fillet for Lanhouin production through application of Doehlert experimental design.

    Science.gov (United States)

    Kindossi, Janvier Mêlégnonfan; Anihouvi, Victor Bienvenu; Vieira-Dalodé, Générose; Akissoé, Noël Houédougbé; Hounhouigan, Djidjoho Joseph

    2016-03-01

    Lanhouin is a traditional fermented salted fish made from the spontaneous and uncontrolled fermentation of whole salted cassava fish (Pseudotolithus senegalensis) mainly produced in the coastal regions of West Africa. The combined effects of NaCl, citric acid concentration, and marination time on the physicochemical and microbiological characteristics of the fish fillet used for Lanhouin production were studied using a Doehlert experimental design with the objective of preserving its quality and safety. The marination time has significant effects on total viable and lactic acid bacteria counts, and NaCl content of the marinated fish fillet while the pH was significantly affected by citric acid concentration and marination duration with high regression coefficient R (2) of 0.83. The experiment showed that the best conditions for marination process of fish fillet were salt ratio 10 g/100 g, acid citric concentration 2.5 g/100 g, and marination time 6 h. These optimum marinating conditions obtained present the best quality of marinated flesh fish leading to the safety of the final fermented product. This pretreatment is necessary in Lanhouin production processes to ensure its safety quality.

  7. Study of the liquid-film-forming apparatus as an alternative aeration system: design criteria and operating condition.

    Science.gov (United States)

    Hongprasith, Narapong; Imai, Tsuyoshi; Painmanakul, Pisut

    2017-06-01

    Aeration is an important factor in aquaculture systems because it is a vital condition for all organisms that live in water and respire aerobically. Generally, mechanical surface aerators are widely used in Thailand due to their advantage for increasing dissolved oxygen (DO) and for their horizontal mixing of aquaculture ponds with large surface areas. However, these systems still have some drawbacks, primarily the low oxygen transfer efficiency (OTE) and energy. Regarding this issue, alternative aeration systems should be studied and applied. Therefore, this research aims to study the aeration mechanism obtained by the diffused-air aeration combined with a liquid-film-forming apparatus (LFFA). The effect of gas flow rates, types, and patterns of aerator installation were investigated in an aquaculture pond of 10 m × 10 m × 1.5 m. The analytical parameters were volumetric mass transfer coefficient (kLa), OTE, and aeration efficiency (AE). From the results, the '4-D' with partitions was proposed as the suitable pattern for the LFFA installation. The advantage could be obtained from high energy performance with 1.2 kg/kW h of AE. Then, the operation conditions can be applied as a design guideline for this alternative aeration system in the aquaculture ponds.

  8. Study on a method to set design hydrographic conditions; Sekkei kaisho no setteiho ni kansuru kenkyu. 2

    Energy Technology Data Exchange (ETDEWEB)

    Toki, N. [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)

    1996-10-01

    Analyses were performed recently on results of observations having been carried out by the U.S. National Oceanic and Atmospheric Administration (NOAA) and the Japanese Meteorological Agency by using wave observation buoys. Wave observation database with high reliability has become publicized in the same format as the conventional wave generation frequency data. In order to obtain rational base for a method to set hazardous sea areas, the present study has attempted to express as a function of the average wave cycle a maximum value of significant wave heights which can be generated based on these data. What were derived include observations by the NOAA over large areas, such as Alaskan coasts, Mexico Bay and Five Great Lakes, the results of discussions by the Meteorological Agency on data including wave observations at five locations in neighboring waters in Japan, and the relationship between the maximum value of significant wave heights that can be generated and the average cycle. Deriving the standard deviation per unit wave height by computing short time estimation from the above data, and deriving combination of the average cycle with angles of encounter can present the design hydrographic conditions (hazardous hydrographic conditions). The future would require not only investigations and discussions from the viewpoint of the maximum value that can occur, but also from the viewpoint of determination of limitations of vessel operations. 5 refs., 5 figs.

  9. Design, simulations, and conditioning of 500 kW fundamental power couplers for a superconducting rf gun

    Directory of Open Access Journals (Sweden)

    Wencan Xu

    2012-07-01

    Full Text Available A half-cell superconducting rf electron gun is designed to provide 0.5 A, 2 MeV beam for the Brookhaven National Laboratory R&D Energy Recovery Linac. Total rf power of 1 MW must be delivered to beam to meet the beam current and energy specifications, resulting in very strong coupling. Two opposing fundamental power couplers (FPCs are employed to minimize the transverse kick to beam traversing the structure and to halve the power through the coupler. A single-window coaxial coupler has been designed to meet the average power and rf coupling requirements. The coupler features a planar beryllia rf window for better handling high thermal stresses and a “pringle”-shaped tip of the antenna for enhancing rf coupling. Two FPCs have been fabricated and tested in preparation for the gun cryomodule assembly. A room-temperature test stand was used for conditioning couplers in full reflection regime with variable phase of the reflecting wave. The couplers were tested up to 250 kW in pulse mode and 125 kW in cw mode at different settings of the reflecting wave phase to expose all rf surfaces along the couplers to high fields. Several multipacting barriers were encountered and successfully processed away. The rf power levels, at which multipacting was found, match well those found in computer simulations.

  10. Higher adsorption capacity of Spirulina platensis alga for Cr(VI) ions removal: parameter optimisation, equilibrium, kinetic and thermodynamic predictions.

    Science.gov (United States)

    Gunasundari, Elumalai; Senthil Kumar, Ponnusamy

    2017-04-01

    This study discusses about the biosorption of Cr(VI) ion from aqueous solution using ultrasonic assisted Spirulina platensis (UASP). The prepared UASP biosorbent was characterised by Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer-Emmet-Teller, scanning electron spectroscopy and energy dispersive X-ray and thermogravimetric analyses. The optimum condition for the maximum removal of Cr(VI) ions for an initial concentration of 50 mg/l by UASP was measured as: adsorbent dose of 1 g/l, pH of 3.0, contact time of 30 min and temperature of 303 K. Adsorption isotherm, kinetics and thermodynamic parameters were calculated. Freundlich model provided the best results for the removal of Cr(VI) ions by UASP. The adsorption kinetics of Cr(VI) ions onto UASP showed that the pseudo-first-order model was well in line with the experimental data. In the thermodynamic study, the parameters like Gibb's free energy, enthalpy and entropy changes were evaluated. This result explains that the adsorption of Cr(VI) ions onto the UASP was exothermic and spontaneous in nature. Desorption of the biosorbent was done using different desorbing agents in which NaOH gave the best result. The prepared material showed higher affinity for the removal of Cr(VI) ions and this may be an alternative material to the existing commercial adsorbents.

  11. Cr(VI) removal from wastewater using low cost sorbent materials: roots of Typha latifolia and ashes.

    Science.gov (United States)

    Barrera-Díaz, C; Colín-Cruz, A; Ureña-Nuñez, F; Romero-Romo, M; Palomar-Pardavé, M

    2004-08-01

    This work presents conditions for hexavalent chromium (Cr(VI)) removal from aqueous solution using different sorbent materials, namely: pyrolytic ashes of an industrial sludge from wastewater treatment and roots of Typha latifolia. The sorbent materials were characterized using scanning electron microscopy (SEM) and surface area using the Brunauer-Emmett-Teller (BET) technique, before and after the contact with the chromium-containing aqueous media. An overall Cr(VI) concentration reduction of 45% was achieved using the roots of Typha latifolia whereas in the case of pyrolytic ashes a 60% removal was observed. The percentage removal was found to depend on the initial Cr(VI) concentration in aqueous solution, pH and temperature. The Cr(VI) uptake process was maximum at pH 2 and a temperature of 40 degrees C for both sorbents. These materials showed a Cr(VI) adsorption capacity that was adequately described by the Langmuir adsorption isotherm. It was demonstrated that the use of waste materials for the treatment of Cr(VI)-containing wastewater is an effective and economical alternative method.

  12. An organic-reagent-free method for determination of chromium(VI) in steel alloys, sewage sludge and wastewater.

    Science.gov (United States)

    Fan, Jing; Sun, Yuping; Wang, Jianji; Fan, Maohong

    2009-04-27

    One of the active areas of green chemistry research and development is in the development of new analytical methods and techniques that reduce and eliminate the use and generation of hazardous substances. In this work, a rapid and organic-reagent-free method was developed for the determination of chromium(VI) by sequential injection analysis (SIA). The method was based on the detection of a blue unstable intermediate compound resulting from the reaction of Cr(VI) with hydrogen peroxide (H(2)O(2)) in acidic medium. H(2)O(2) and its reaction products were environmentally friendly, and chromogenic reagents and organic solvents were not used in the proposed method. Different SIA parameters have been optimized and used to obtain the analytical figures of merit. Under the optimum experimental conditions, the linear range for Cr(VI) was 0.5-100.0 microg mL(-1), and the detection limit was 0.16 microg mL(-1). The sample throughput was 80 h(-1), and the total volume of only 145 microL was consumed in each determination of Cr(VI). The method was applied for the determination of Cr(VI) in seven real samples, including alloy steel, sewage sludge and wastewater samples, and the results were compared with those obtained by atomic absorption spectrometry as well as with the certified value of Cr(VI) in standard reference material. Statistical analysis revealed that there was no significant difference at 95% confidence level.

  13. Treatment of Cr(VI)-containing wastewaters with exopolysaccharide-producing cyanobacteria in pilot flow through and batch systems

    Energy Technology Data Exchange (ETDEWEB)

    Colica, Giovanni; Mecarozzi, Pier Cesare; De Philippis, Roberto [Florence Univ., Firenze (Italy). Dept. of Agricultural Biotechnology

    2010-08-15

    Seven exopolysaccharide-producing cyanobacteria were tested with regard to their capability to remove Cr(VI) from the wastewater of a plating industry. The cyanobacterium which showed, under lab conditions, the most promising features with regard to both Cr(VI) removal (about 12 mg of Cr(VI) removed per gram of dry biomass) and growth characteristics (highest growth rate and simplest culture medium) was Nostoc PCC7936. Furthermore, in lab experiments, it was also found that a HCl pretreatment is essential to abate the concentration of Cr(VI) in solution and that the viability of the biomass is not necessary. Subsequently, three pilot devices were tested, one batch (a dialysis cell) and two flow-through systems (a filter press and a column filled with quartz grain). The best performances were obtained with the filter press, where it was observed a sharp decrease in the concentration of Cr(VI), partly due to the adsorption of the metal by the biomass (about 50%) and partly due to its reduction to Cr(III). The results are discussed in terms of the role played by the different components (biomass and polysaccharide) of the cyanobacterial cultures in the removal of Cr(VI). (orig.)

  14. Influence of nickel (II) and chromium (VI) on the laboratory scale rotating biological contactor.

    Science.gov (United States)

    Taşeli, B K; Gökçay, C F; Gürol, A

    2008-09-01

    High concentration of heavy metals is toxic for most microorganisms and cause strict damage in wastewater treatment operations and often a physico-chemical pretreatment prior to biological treatment is considered necessary. However, in this study it has been shown that biological systems can adapt to Ni (II) and Cr (VI) when their concentration is below 10 and 20 mg/L, respectively. The aim of this study was to evaluate the effect of Ni (II) and Cr (VI) on the lab-scale rotating biological contactor process. It was found that, addition of Ni (II) up to 10 mg/L did not reduce the chemical oxygen demand removal efficiency and on the contrary concentrations below 10 mg/L improved the performance. The influent Ni (II) concentration of 1 mg/L was the concentration where the treatment efficiency produced a maximum COD removal of 86.5%. Moreover, Ni (II) concentration above 10 mg/L was relatively toxic to the system and produced lower treatment efficiencies than the baseline study without Ni (II). Turbidity and suspended solids removals were not stimulated to a great extent with nickel. Addition of Ni (II) did not seem to affect the pH of the system during treatment. The dissolved oxygen concentration did not drop below 4 mg/L at all concentrations of Ni (II) indicating aerobic conditions prevailed in the system. Experiments conducted with Cr (VI) revealed that addition of Cr (VI) up to 20 mg/L did not reduce the COD removal efficiency and on the contrary concentrations below 20 mg/L improved the performance. The influent Cr (VI) concentration of 1 mg/L was the concentration where the treatment efficiency produced a maximum COD removal of 88%. Turbidity and SS removals were more efficient at 5 mg/L Cr (VI) concentration, rather than 1 mg/L, which lead to the conclusion that 5 mg/L Cr (VI) concentration is the optimum concentration, in terms of COD, turbidity and SS removals. Similar with Ni (II) experiments, addition of Cr (VI) did not significantly affect the pH value of

  15. Advanced oxidation process based on the Cr(III)/Cr(VI) redox cycle.

    Science.gov (United States)

    Bokare, Alok D; Choi, Wonyong

    2011-11-01

    Oxidative degradation of aqueous organic pollutants, using 4-chlorophenol (4-CP) as a main model substrate, was achieved with the concurrent H(2)O(2)-mediated transformation of Cr(III) to Cr(VI). The Fenton-like oxidation of 4-CP is initiated by the reaction between the aquo-complex of Cr(III) and H(2)O(2), which generates HO(•) along with the stepwise oxidation of Cr(III) to Cr(VI). The Cr(III)/H(2)O(2) system is inactive in acidic condition, but exhibits maximum oxidative capacity at neutral and near-alkaline pH. Since we previously reported that Cr(VI) can also activate H(2)O(2) to efficiently generate HO(•), the dual role of H(2)O(2) as an oxidant of Cr(III) and a reductant of Cr(VI) can be utilized to establish a redox cycle of Cr(III)-Cr(VI)-Cr(III). As a result, HO(•) can be generated using both Cr(III)/H(2)O(2) and Cr(VI)/H(2)O(2) reactions, either concurrently or sequentially. The formation of HO(•) was confirmed by monitoring the production of p-hydroxybenzoic acid from [benzoic acid + HO(•)] as a probe reaction and by quenching the degradation of 4-CP in the presence of methanol as a HO(•) scavenger. The oxidation rate of 4-CP in the Cr(III)/H(2)O(2) solution was highly influenced by pH, which is ascribed to the hydrolysis of Cr(III)(H(2)O)(n) into Cr(III)(H(2)O)(n-m)(OH)(m) and the subsequent condensation to oligomers. The present study proposes that the Cr(III)/H(2)O(2) combined with Cr(VI)/H(2)O(2) process is a viable advanced oxidation process that operates over a wide pH range using the reusable redox cycle of Cr(III) and Cr(VI).

  16. Design of Organic Transformations at Ambient Conditions: Our Sincere Efforts to the Cause of Green Chemistry Practice.

    Science.gov (United States)

    Brahmachari, Goutam

    2016-02-01

    This account summarizes our recent efforts in designing a good number of important organic transformations leading to the synthesis of biologically relevant compounds at room temperature and pressure. Currently, the concept of green chemistry is globally acclaimed and has already advanced quite significantly to emerge as a distinct branch of chemical sciences. Among the principles of green chemistry, one principle is dedicated to the "design of energy efficiency" - that is, to develop synthetic strategies that require less or the minimum amount of energy to carry out a specific reaction with optimum productivity - and the most effective way to save energy is to develop strategies/protocols that are capable enough to carry out the transformations at ambient temperature! As part of on-going developments in green synthetic strategies, the design of reactions under ambient conditions coupled with other green aspects is, thus, an area of current interest. The concept of developing reaction strategies at room temperature and pressure is now an emerging field of research in organic chemistry and is progressing steadily. This account is aimed to offer an overview of our recent research works directly related to this particular field of interest, and highlights the green chemistry practice leading to carbon-carbon and carbon-heteroatom bond-forming reactions of topical significance. Green synthetic routes to a variety of biologically relevant organic molecules (heterocyclic, heteroaromatic, alicyclic, acyclic, etc.) at room temperature and pressure are discussed. © 2015 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. A Comparison of Naturally-Occurring and Artificially Stimulated Uranium(VI) Bioreduction in Sediment from a Field-scale Experiment in Rifle, CO

    Science.gov (United States)

    Campbell, K. M.; Williams, K. H.; Lesher, E.; Davis, J. A.; Long, P. E.

    2007-12-01

    Long-term remediation of uranium (U)-contaminated groundwater poses one of the greatest challenges in the clean-up of impacted sites. One solution is to reduce dissolved U(VI) to insoluble U(IV) precipitates by stimulating indigenous metal reducing bacterial populations in situ. Contamination from a former U mine tailings repository (Rifle, CO) provides a research site to study the efficacy of biostimulated U(VI) reduction at the field scale. Several cores were drilled in June 2007 across a region of naturally-occurring U(VI) bioreduction. The cores represent a cross section of sediment that ranges from minimally reducing to highly reducing. Anaerobic sediment samples from the cores were analyzed for labile U(VI) content by carbonate extraction in anoxic conditions (pH 9.4, 14 mM NaHCO3, 2.8 mM Na2CO¬3). A subset of the same core sections were dried and oxidized by exposure to air for 2 weeks. The carbonate extraction was repeated, and the amount of U(IV) present in the anaerobic sample was calculated by difference between the anoxic and oxidized extractions. An acid extraction was also performed on the oxidized sediments to compare the carbonate extractable and the acid extractable U fractions. The highest U concentrations were found in the highly bioreduced sediment, with the majority of U present as U(IV) (66-92%). The regions of highest bioreduction also correspond to elevated concentrations of solid phase organic carbon, suggesting that natural bioreduction is stimulated by zones of increased organic carbon content. The same field site was then used for an artificially stimulated bioreduction experiment, where the indigenous bacterial community was stimulated by injecting acetate upgradient of the core collection location. Carbonate and acid extractions were performed on core samples taken after the completion of the acetate injection. This work evaluates the composition of the sediment before and after biostimulation as a way of directly comparing the extent

  18. Exploratory results from a new rotary shear designed to reproduce the extreme deformation conditions of crustal earthquakes

    Science.gov (United States)

    Di Toro, G.; Nielsen, S. B.; Spagnuolo, E.; Smith, S.; Violay, M. E.; Niemeijer, A. R.; Di Felice, F.; Di Stefano, G.; Romeo, G.; Scarlato, P.

    2011-12-01

    A challenging goal in experimental rock deformation is to reproduce the extreme deformation conditions typical of coseismic slip in crustal earthquakes: large slip (up to 50 m), slip rates (0.1-10 m/s), accelerations (> 10 m/s2) and normal stress (> 50 MPa). Moreover, fault zones usually contain non-cohesive rocks (gouges) and fluids. The integration of all these deformation conditions is such a technical challenge that there is currently no apparatus in the world that can reproduce seismic slip. Yet, the determination of rock friction at seismic slip rates remains one of the main unknowns in earthquake physics, as it cannot be determined (or very approximately) by seismic wave inversion analysis. In the last thirty years, rotary shear apparatus were designed that combine large normal stresses and slip but low slip rates (high-pressure rotary shears first designed by Tullis) or low normal stresses but large slip rates and slip (rotary shears first designed by Shimamoto). Here we present the results of experiments using a newly-constructed Slow to HIgh Velocity Apparatus (SHIVA), installed at INGV in Rome, which extends the combination of normal stress, slip and slip rate achieved by previous apparatus and reproduces the conditions likely to occur during an earthquake in the shallow crust. SHIVA uses two brushless engines (max power 300 kW, max torque 930 Nm) and an air actuator (thrust 5 tons) in a rotary shear configuration (nominally infinite displacement) to slide hollow rock cylinders (30/50 mm int./ext. diameter) at slip rates ranging from 10 micron/s up to 6.5 m/s, accelerations up to 80 m/s2 and normal stresses up to 50 MPa. SHIVA can also perform experiments in which the torque on the sample (rather than the slip rate) is progressively increased until spontaneous failure occurs: this experimental capability should better reproduce natural conditions. The apparatus is equipped with a sample chamber to carry out experiments in the presence of fluids (up to 15

  19. Farvel til globaliseringen som vi kendte den

    DEFF Research Database (Denmark)

    Böss, Michael

    2009-01-01

    Vi er endt med en krise, som rækker langt ud over det globale monetære system, fordi den ideologiske ortodoksi, der skabte den, har ført til udflytning af millioner af arbejdspladser, tæring af nationalstaternes sammenhængskraft og overgreb på naturen. Kronikken refererer bl.a. til John Maynard...... Keynes og en artikel af økonomen Robert Skidelsky i The American Prospect. Udgivelsesdato: 12. januar 2009...

  20. "LICENS ER NOGET VI GIVER TIL HINANDEN"

    OpenAIRE

    Svendsen, Nana Lysbo; Birksholm, Sarah Schlander; Rosendahl, Rasmus; Albrechtsen, Nadja Loran

    2013-01-01

    This study consists of a rhetorical analysis of how the Danish Broadcasting Corporation argues for the compulsory license fee in their campaign video: ’Licens er noget vi giver til hinanden’. On the assumption that a visual product can argue on equal terms with the spoken language, the paper will look at the specific visual tools that are used in the argumentation and the portrayal of the concept of public service and the license fee. In extension to this the paper will examine if the vid...

  1. A field-scale reactive transport model for U(VI) migration influenced by coupled multirate mass transfer and surface complexation reactions

    Science.gov (United States)

    Ma, R.; Zheng, C.; Prommer, H.; Greskowiak, J.; Liu, C.; Zachara, J.; Rockhold, M.

    2010-05-01

    This study explores field-scale modeling of U(VI) reactive transport through incorporation of laboratory and field data. A field-scale reactive transport model was developed on the basis of laboratory-characterized U(VI) surface complexation reactions (SCRs) and multirate mass transfer processes, as well as field-measured hydrogeochemical conditions at the U.S. Department of Energy, Hanford 300 Area (300 A), Washington. The model was used to assess the importance of multirate mass transfer processes on U(VI) reactive transport and to evaluate the effect of variable geochemical conditions caused by dynamic river water-groundwater interactions on U(VI) plume migration. Model simulations revealed complex spatiotemporal relationships between groundwater composition and U(VI) speciation, adsorption, and plume migration. In general, river water intrusion enhances uranium adsorption and lowers aqueous uranium concentration because river water dilution increases pH and decreases aqueous bicarbonate concentration, leading to overall enhanced U(VI) surface complexation. Strong U(VI) retardation was computed for the field-measured hydrogeochemical conditions, suggesting a slow dissipation of the U(VI) plume, a phenomenon consistent with field observations. The simulations also showed that SCR-retarded U(VI) migration becomes more dynamic and synchronous with the groundwater flow field when multirate mass transfer processes are involved. Breakthrough curves at selected locations and the temporal changes in the calculated mass during the 20 year simulation period indicated that uranium adsorption/desorption never attained steady state because of the dynamic flow field and groundwater composition variations caused by river water intrusion. Thus, the multirate SCR model appears to be a crucial consideration for future reactive transport simulations of uranium contaminants at the Hanford 300 A site and elsewhere under similar hydrogeochemical conditions.

  2. Oral–Facial–Digital Syndrome type VI with self mutilations

    Directory of Open Access Journals (Sweden)

    Rabah M. Shawky

    2014-10-01

    Full Text Available We report the case of a 2.5 year old female, 2nd in order of birth of 1st cousin consanguineous marriage, with the typical features of Oral–Facial–Digital Syndrome type VI (OFDS VI including midline pseudo cleft upper lip, sublingual nodule, molar tooth sign by MRI brain, bilateral mesoaxial polydactyly (hexadactyly, and developmental delay. The patient had self mutilations which was not reported before in OFDS VI except once.

  3. Model parameters conditioning on regional hydrologic signatures for process-based design flood estimation in ungauged basins.

    Science.gov (United States)

    Biondi, Daniela; De Luca, Davide Luciano

    2015-04-01

    making and in hydraulic design. The obtained results highlight the relevant impact of uncertainty in regional estimates of hydrological signatures on posterior parameters distribution and on uncertainty bounds of simulated peak discharges. The results of the continuous simulation, generally, better matched those of the statistical flood frequency analysis, thus this approach is recommended for the flood frequency analysis in the study area. REFERENCES Biondi D, Claps P, Cruscomagno F, De Luca DL, Fiorentino M, Ganora D, Gioia A, Iacobellis V, Laio F, Manfreda S, Versace P (2012). Dopo il VAPI: la valutazione delle massime portate al colmo di piena nell'esperienza del POR Calabria (in Italian). Proceedings of XXXIII Italian National Conference on Hydraulics and Hydraulic Engineering, Brescia - Italy, 10-15 September 2012. Bulygina N, McIntyre N, Wheater HS (2009). Conditioning rainfall- runoff model parameters for ungauged catchments and land management impacts analysis. Hydrol Earth Syst Sci 13:893-904. doi:10.5194/hess-13-893-2009. Bulygina N, McIntyre N, Wheater H (2011). Bayesian conditioning of a rainfall-runoff model for predicting flows in ungauged catchments and under land use changes. Water Resour Res 47: W02503. doi:10.1029/2010WR009240. Gupta HV, Wagener T, Liu Y (2008). Reconciling theory with observations: elements of a diagnostic approach to model evaluation. Hydrol Process 22: 3802-3813. doi:10.1002/hyp.6989. Laio F, Ganora D, Claps P, Galeati G (2011). Spatially smooth regional estimation of the flood frequency curve (with uncertainty). J Hydrol 408: 67-77.

  4. Fremtidens lavenergibyggeri - kan vi gøre som vi plejer?

    DEFF Research Database (Denmark)

    Larsen, Tine Steen

    2011-01-01

    Stramninger af kravene til energiforbruget i vores boliger medfører stor fokus på energiberegningen, men erfaringer fra lavenergiboliger opført i dag viser, at vi, for at sikre succes for fremtidens boliger, også skal inddrage dokumentation af indeklimaet og forbedre samarbejdet mellem arkitekter...

  5. Vi lider af prætraumatisk stress

    DEFF Research Database (Denmark)

    Hansen, Brian Benjamin

    2009-01-01

    Vi lider af prætraumatisk stress. Vi vil nemlig nå det hele og presser konstant nye aftaler ind i vores kalender. Det eneste, der hjælper, er at ’gøre intet’ – men kan man overhovedet det? Udgivelsesdato: 30.09.09......Vi lider af prætraumatisk stress. Vi vil nemlig nå det hele og presser konstant nye aftaler ind i vores kalender. Det eneste, der hjælper, er at ’gøre intet’ – men kan man overhovedet det? Udgivelsesdato: 30.09.09...

  6. Behaviour of chromium(VI) in stormwater soil infiltration systems

    DEFF Research Database (Denmark)

    Cederkvist, Karin; Ingvertsen, Simon T.; Jensen, Marina B.

    2013-01-01

    The ability of stormwater infiltration systems to retain Cr(VI) was tested by applying a synthetic stormwater runoff solution with a neutral pH and high Cr(VI) concentrations to four intact soil columns excavated from two roadside infiltration swales in Germany. Inlet flow rates mimicked normal (10......, while under extreme rain events approximately 20% of Cr(VI) was retained. In both cases effluent concentrations of Cr(VI) would exceed the threshold value of 3.4 mu g/L if the infiltrated water were introduced to freshwater environments. More knowledge on the composition of the stormwater runoff...

  7. Remediation of Cr(VI) in solution using vitamin C*

    OpenAIRE

    LIU, Yong; Xu, Xin-hua; He, Ping

    2005-01-01

    The effectiveness of vitamin C in treating Cr(VI)-contaminated water is being evaluated. Cr(VI) is an identified pollutant of some soils and groundwater. Vitamin C, an important biological reductant in humans and animals, can be used to transform Cr(VI) to essentially nontoxic Cr(III). The removal efficiency was 89% when the mass concentration of vitamin C was 80 mg/L in 60 min, and nearly 100% Cr(VI) was removed when the mass concentration was 100 mg/L. Our data demonstrated that the removal...

  8. Heterogeneity of collagens in rabbit cornea: type VI collagen

    National Research Council Canada - National Science Library

    Cintron, C; Hong, BS

    1988-01-01

    .... These physical characteristics, together with the susceptibility of these polypeptides to collagenase and their amino acid composition, identified the high molecular weight aggregate as type VI collagen...

  9. Late Neanderthals at Jarama VI (central Iberia)?

    Science.gov (United States)

    Kehl, Martin; Burow, Christoph; Hilgers, Alexandra; Navazo, Marta; Pastoors, Andreas; Weniger, Gerd-Christian; Wood, Rachel; Jordá Pardo, Jesús F.

    2013-09-01

    Previous geochronological and archaeological studies on the rock shelter Jarama VI suggested a late survival of Neanderthals in central Iberia and the presence of lithic assemblages of Early Upper Paleolithic affinity. New data on granulometry, mineralogical composition, geochemical fingerprints and micromorphology of the sequence corroborate the previous notion that the archaeological units JVI.2.1 to JVI.2.3 are slackwater deposits of superfloods, which did not experience significant post-depositional changes, whereas the artifact-rich units JVI.3 and JVI.1 mainly received sediment inputs by sheetwash and cave spall. New AMS radiocarbon measurements on three samples of cut-marked bone using the ultrafiltration technique yielded ages close to, or beyond, the limit of radiocarbon dating at ca. 50 14C ka BP, and hence suggest much higher antiquity than assumed previously. Furthermore, elevated temperature post-IR IRSL luminescence measurements on K feldspars yielded burial ages for subunits JVI.2.2 and JVI.2.3 between 50 and 60 ka. Finally, our reappraisal of the stone industry strongly suggests that the whole sequence is of Mousterian affinity. In conclusion, Jarama VI most probably does not document a late survival of Neanderthals nor an Early Upper Paleolithic occupation in central Iberia, but rather indicates an occupation breakdown after the Middle Paleolithic.

  10. Investigation of uranium (VI) adsorption by polypyrrole.

    Science.gov (United States)

    Abdi, S; Nasiri, M; Mesbahi, A; Khani, M H

    2017-06-15

    The purpose of this study was to investigate the adsorption of uranium (VI) ions on the polypyrrole adsorbent. Polypyrrole was synthesized by a chemical method using polyethylene glycol, sodium dodecylbenzenesulfonate, and cetyltrimethylammonium bromide as the surfactant and iron (III) chloride as an oxidant in the aqueous solution. The effect of various surfactants on the synthesized polymers and their performance as the uranium adsorbent were investigated. Adsorbent properties were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The effect of different parameters such as pH, contact time, initial metal ion concentrations, adsorbent dose, and the temperature was investigated in the batch system for uranium adsorption process. It has been illustrated that the adsorption equilibrium time is 7min. The results showed that the Freundlich model had the best agreement and the maximum adsorption capacity of polypyrrole for uranium (VI) was determined 87.72mg/g from Langmuir isotherm. In addition, the mentioned adsorption process was fast and the kinetic data were fitted to the Pseudo first and second order models. The adsorption kinetic data followed the pseudo-second-order kinetic model. Moreover, the thermodynamic parameters ΔG(0), ΔH(0) and ΔS(0) showed that the uranium adsorption process by polypyrrole was endothermic and spontaneous. Copyright © 2017. Published by Elsevier B.V.

  11. AFS-2 FLOWSHEET MODIFICATIONS TO ADDRESS THE INGROWTH OF PU(VI) DURING METAL DISSOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Crapse, K.; Rudisill, T.; O' Rourke, P.; Kyser, E.

    2014-07-02

    In support of the Alternate Feed Stock Two (AFS-2) PuO{sub 2} production campaign, Savannah River National Laboratory (SRNL) conducted a series of experiments concluding that dissolving Pu metal at 95°C using a 6–10 M HNO{sub 3} solution containing 0.05–0.2 M KF and 0–2 g/L B could reduce the oxidation of Pu(IV) to Pu(VI) as compared to dissolving Pu metal under the same conditions but at or near the boiling temperature. This flowsheet was demonstrated by conducting Pu metal dissolutions at 95°C to ensure that PuO{sub 2} solids were not formed during the dissolution. These dissolution parameters can be used for dissolving both Aqueous Polishing (AP) and MOX Process (MP) specification materials. Preceding the studies reported herein, two batches of Pu metal were dissolved in the H-Canyon 6.1D dissolver to prepare feed solution for the AFS-2 PuO{sub 2} production campaign. While in storage, UV-visible spectra obtained from an at-line spectrophotometer indicated the presence of Pu(VI). Analysis of the solutions also showed the presence of Fe, Ni, and Cr. Oxidation of Pu(IV) produced during metal dissolution to Pu(VI) is a concern for anion exchange purification. Anion exchange requires Pu in the +4 oxidation state for formation of the anionic plutonium(IV) hexanitrato complex which absorbs onto the resin. The presence of Pu(VI) in the anion feed solution would require a valence adjustment step to prevent losses. In addition, the presence of Cr(VI) would result in absorption of chromate ion onto the resin and could limit the purification of Pu from Cr which may challenge the purity specification of the final PuO{sub 2} product. Initial experiments were performed to quantify the rate of oxidation of Pu(IV) to Pu(VI) (presumed to be facilitated by Cr(VI)) as functions of the HNO{sub 3} concentration and temperature in simulated dissolution solutions containing Cr, Fe, and Ni. In these simulated Pu dissolutions studies, lowering the temperature from near boiling

  12. Dispersion-free solvent extraction of Cr(VI) from acidic solutions using hollow fiber contactor.

    Science.gov (United States)

    Alguacil, Francisco J; Alonso, Manuel; Lopez, Félix A; Lopez-Delgado, Aurora; Padilla, Isabel

    2009-10-15

    The use of dispersión-free solvent extraction, through microporous hydrophobic membrane has been investigated. The hollow fiber contactor, with surface area of 1.4 m2 was used to extract Cr(VI) (0.005-0.12 g/L from aqueous sulphuric acidic media (pH 2.5-4.2 +/- 0.05). Several parameters such as extractant concentration, feed acidity and metal concentration in the initial aqueous solution were investigated. Results revealed that 15% v/v Cyanex 923 in Exxsol D-100 as organic phase and feed in the 2.5 pH range, gave optimum extraction (exceeding 95%) of Cr(VI) and it was possible to strip using 10 g/L hydrazine sulfate (also with recoveries exceeding 95%). In this step, Cr(VI) is immediately reduced to the less hazardous Cr(III) state. Results also showed that under the various experimental conditions, chromium(VI) extraction was rate-controlled by the interfacial reaction on the membrane surface. Typical overall mass transfer coefficients values are 4.2 x 10(-5) and 3.6 x 10(-6) cm/s for extraction and stripping operations, respectively.

  13. One-way ViSP (Visually Servoed Paired structured light system) for structural displacement monitoring

    Science.gov (United States)

    Jeon, H.; Kim, Y. J.; Myeong, W.; Myung, H.

    2017-08-01

    Nowadays, the evaluation of structural safety and serviceability is becoming more essential due to the deterioration of civil infrastructures. In particular, the structural displacement which provides important information on structural conditions is considered one of the important indicators for the health monitoring of structures. To estimate the structural displacement, this paper proposes a one-way projection-type six degree-of-freedom (DOF) displacement measurement system based on vision and laser sensors, named one-way ViSP (Visually Servoed Paired structured light system). The system is composed of a transmitter and a receiver, which are facing to each other. The transmitter consists of a 1D laser range finder, two lasers, and a 2-DOF manipulator, while the receiver consists of a screen and a camera. The one-way ViSP estimates relative displacements between a transmitter and receiver by measuring the coordinates of three projected beam spots and a distance. Besides the advantages such as high accuracy in 6-DOF displacement measurement, low cost, and real-time monitoring possibilities, the one-way ViSP can cover large areas such as dams and inclined planes by using multiple receivers. Through various simulations and experiments, it is shown that the one-way ViSP has high accuracy in 6-DOF displacement estimation.

  14. Reduction and Removal of Chromium VI in Water by Powdered Activated Carbon

    Directory of Open Access Journals (Sweden)

    Yanan Chen

    2018-02-01

    Full Text Available Cr adsorption on wood-based powdered activated carbon (WPAC was characterized by scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS. The highest Cr(VI adsorption (40.04% was obtained under acidic conditions (pH 3, whereas Cr removal at pH 10 was only 0.34%. The mechanism of Cr(VI removal from aqueous solutions by WPAC was based on the reduction of Cr(VI to Cr(III with the concomitant oxidation of C-H and C-OH to C-OH and C=O, respectively, on the surface of WPAC, followed by Cr(III adsorption. Raman spectroscopy revealed a change in the WPAC structure in terms of the D/G band intensity ratio after Cr(VI adsorption. SEM-EDS analysis showed that the oxygen/carbon ratio on the WPAC surface increased from 9.85% to 17.74%. This result was confirmed by XPS measurements, which showed that 78.8% of Cr adsorbed on the WPAC surface was in the trivalent state. The amount of oxygen-containing functional groups on the surface increased due to the oxidation of graphitic carbons to C-OH and C=O groups.

  15. Injury Risk Assessment of Extravehicular Mobility Unit (EMU) Phase VI and Series 4000 Gloves During Extravehicular Activity (EVA) Hand Manipulation Tasks

    Science.gov (United States)

    Kilby, Melissa

    2015-01-01

    Functional Extravehicular Mobility Units (EMUs) with high precision gloves are essential for the success of Extravehicular Activity (EVA). Previous research done at NASA has shown that total strength capabilities and performance are reduced when wearing a pressurized EMU. The goal of this project was to characterize the human-space suit glove interaction and assess the risk of injury during common EVA hand manipulation tasks, including pushing, pinching and gripping objects. A custom third generation sensor garment was designed to incorporate a combination of sensors, including force sensitive resistors, strain gauge sensors, and shear force sensors. The combination of sensors was used to measure the forces acting on the finger nails, finger pads, finger tips, as well as the knuckle joints. In addition to measuring the forces, data was collected on the temperature, humidity, skin conductance, and blood perfusion of the hands. Testing compared both the Phase VI and Series 4000 glove against an ungloved condition. The ungloved test was performed wearing the sensor garment only. The project outcomes identified critical landmarks that experienced higher workloads and are more likely to suffer injuries. These critical landmarks varied as a function of space suit glove and task performed. The results showed that less forces were acting on the hands while wearing the Phase VI glove as compared to wearing the Series 4000 glove. Based on our findings, the engineering division can utilize these methods for optimizing the current space suit glove and designing next generation gloves to prevent injuries and optimize hand mobility and comfort.

  16. Dom João VI's death: convulsions and coma Morte de Dom João VI: convulsões e coma

    Directory of Open Access Journals (Sweden)

    Marleide da Mota Gomes

    2007-12-01

    Full Text Available Dom João VI's death occurred in adverse political conditions that led to the regicide hypothesis. The main aim of this paper is to mention life style and conditions of the death of the king by means of narrative review based on primary and secondary sources. Dom João VI died in the way of convulsions and gastrointestinal symptoms. This could be the result of the pathological chain of genetic determination, accentuated by the inappropriate life style, obesity and sedentary habits, and/or poisoning. The finding of arsenic in high doses in his viscera favors the last hypothesis as the basic cause of death, but one can not discard the atherosclerosis predisposing risk factors for a final stroke.A morte de Dom João VI aconteceu em condições políticas adversas que conduziram à hipótese de regicídio. O objetivo principal deste artigo é mencionar o estilo de vida e condições da morte do rei por meio de revisão narrativa baseada em fontes primárias e secundárias. Dom João VI morreu apresentando convulsões e sintomas gastrointestinais. Esse poderia ser o resultado da cadeia patológica de determinação genética, acentuada pelo estilo de vida inapropriado, obesidade e/ou envenenamento. O achado de arsênico em doses altas nas suas vísceras aponta a última hipótese como a causa básica da morte, mas não se pode descartar a aterosclerose como fator de risco predisponente para um acidente vascular cerebral final.

  17. Interaction of monosaccharides and related compounds with oxocations of Mo(VI), W(VI) and U(VI) studied by NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Geraldes, C.F.G.C.; Castro, M.M.C.A.; Saraiva, M.E.; Aureliano, M.; Dias, B.A.

    1988-05-01

    Proton, /sup 13/C and /sup 31/P nuclear magnetic resonance spectroscopy has been used to study the complexation of Mo(VI), W(VI) and U(VI) oxocations with various aldoses, cyclic polyols and ribose-5-phosphate in aqueous solution. The aldoses D-mannose, D-lyxose and D-ribose form tridentate complexes with Mo(VI) and W(VI) at pH similarly ordered 5, via the 1,2,3-hydroxyl groups, which are cis to each other in these sugars. Other aldoses, like D-arabinose, D-glucose, D-xylose and D-galactose form weaker bidentate complexes with those ions because they can only use the 1 and 3-cis hydroxyl groups in metal binding. These bidentate interactions also take place in the binding of U(VI) to D-mannose and D-ribose, at pH similarly ordered 10. However, sugars having 1,3,5-hydroxyl groups in the cis position do not form stable chelates with these oxocations, possibly due to steric crowding. In the case of ribose-5-phosphate, the phosphate group is the exclusive binding site for the three oxocations, except for U(VI) at very basic pH (pH > 10), where the hydroxyl groups also interact with UO/sub 2//sup 2 +/.

  18. The ternary system U(VI) / humic acid / Opalinus Clay

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Claudia

    2013-07-23

    , where the geochemical interaction with uranium contaminated water plays a role. Concerning the suitability of Opalinus Clay as host rock for a nuclear waste repository, it can be concluded, that Opalinus Clay has a relatively high retardation potential for U(VI). In case of water ingress U(VI) as part of the nuclear waste is released into the clay formation. Under near-neutral pH conditions, it will be complexed by calcium and carbonate ions leached out from Opalinus Clay, whereby Ca{sub 2}UO{sub 2}(CO{sub 3}){sub 3}(aq) is formed. This complex is only weakly retarded by sorption onto the clay, which can contribute to an enhanced mobility of U(VI) in the host rock. However, the U(VI) migration through the clay rock is governed by molecular diffusion. This decelerates the migration of Ca{sub 2}UO{sub 2}(CO{sub 3}){sub 3}(aq) through Opalinus Clay and thus it represents the decisive retardation process in the investigated system.

  19. Optimization of culture conditions and medium composition for the marine algicidal bacterium Alteromonas sp. DH46 by uniform design

    Science.gov (United States)

    Lin, Jing; Zheng, Wei; Tian, Yun; Wang, Guizhong; Zheng, Tianling

    2013-09-01

    Harmful algal blooms (HABs) have led to extensive ecological and environmental issues and huge economic losses. Various HAB control techniques have been developed, and biological methods have been paid more attention. Algicidal bacteria is a general designation for bacteria which inhibit algal growth in a direct or indirect manner, and kill or damage the algal cells. A metabolite which is strongly toxic to the dinoflagellate Alexandrium tamarense was produced by strain DH46 of the alga-lysing bacterium Alteromonas sp. The culture conditions were optimized using a single-factor test method. Factors including carbon source, nitrogen source, temperature, initial pH value, rotational speed and salinity were studied. The results showed that the cultivation of the bacteria at 28°C and 180 r min-1 with initial pH 7 and 30 salt contcentration favored both the cell growth and the lysing effect of strain DH46. The optimal medium composition for strain DH46 was determined by means of uniform design experimentation, and the most important components influencing the cell density were tryptone, yeast extract, soluble starch, NaNO3 and MgSO4. When the following culture medium was used (tryptone 14.0g, yeast extract 1.63g, soluble starch 5.0 g, NaNO3 1.6 g, MgSO4 2.3 g in 1L), the largest bacterial dry weight (7.36 g L-1) was obtained, which was an enhancement of 107% compared to the initial medium; and the algal lysis rate was as high as 98.4% which increased nearly 10% after optimization.

  20. Surface complexation modeling of U(VI) adsorption by aquifer sediments from a former mill tailings site at Rifle, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, S. P.; Fox, Patricia M.; Davis, James A.; Campbell, Kate M.; Hayes, Kim F.; Long, Philip E.

    2009-12-15

    U(VI) adsorption by two aquifer sediment samples was studied under oxic conditions as a function of pH, U(VI), Ca, and dissolved carbonate concentration. Background-A (BKG-A) sediment was collected upstream of a former uranium mill-tailings site at Rifle, Colorado, and Little Rusty Composite (LRC) was collected on site but with low U contamination. Batch adsorption experiments were performed using artificial groundwater solutions prepared to simulate the field groundwater composition in equilibrium with specific partial pressures of carbon dioxide. To encompass the geochemical conditions of the alluvial aquifer at the site, the experimental conditions ranged from 6.8×10-8 to 10-5 M in [U(VI)]tot, 7.2 to 8.0 in pH, 3.0×10-3 to 6.0×10-3 M in [Ca2+], and 0.05 to 2.6% in partial pressure of carbon dioxide. The sediment was extracted with a dilute bicarbonate/carbonate solution to determine the background labile U(VI) already present in the sediment. A semi-empirical surface complexation model was developed to describe U(VI) adsorption using FITEQL4. The non-electrostatic, generalized composite surface complexation model successfully simulated U(VI) adsorption over the range of groundwater conditions at the Old Rifle site, using a two-site, two-reaction fitting scheme. The sensitivity of model parameters to background U(VI) concentration on the two samples was evaluated. U(VI) adsorption experiments were also performed using a sand fraction of BKG-A separated through repeated sonication and wet-sieving. Surface area normalized Kd for the bulk and sand fraction indicated similar reactivity for both. The surface complexation model developed in this work is expected to contribute to the prediction of fate and transport of U(VI) in the alluvial aquifer at the Old Rifle site, and to assist in the simulation of biostimulation field experiments performed at the site.

  1. Influence of (calcium-)uranyl-carbonate complexation on U(VI) sorption on Ca- and Na-bentonites.

    Science.gov (United States)

    Meleshyn, A; Azeroual, M; Reeck, T; Houben, G; Riebe, B; Bunnenberg, C

    2009-07-01

    The influence of uranyl-carbonate and calcium-uranyl-carbonate complexations on the kinetics of U(VI) (approximately 3.4 x 10(-3) mol L(-1)) sorption from NaNO3 and Ca(NO3)2 solutions on Na- and Ca-bentonites at circumneutral ambient conditions was investigated. Complexation of U(VI) in Ca2UO2(CO3)3(aq) aqueous species, dominating the U(VI) speciation in Ca(NO3)2 solution, reduces its adsorption on bentonite by a factor of 2-3 in comparison with that in (UO2)2CO3(OH)3- species, dominating in NaNO3 solution, within the studied period of time (21 days). As a result of the dissolution of accessory calcite, Ca2UO2(CO3)3(aq) can be formed in the initially Ca-free solution in contact with either Na- or Ca-bentonite. U(VI) adsorption on Na-bentonite is a factor of approximately 2 higher than that on Ca-bentonite for solutions with the Ca2UO2(CO3)3(aq) complex dominating aqueous U(VI) speciation. This favors use of Na-bentonite over that of Ca-bentonite in final disposal of radioactive waste. Furthermore, the observed strong correlation between U(VI) adsorption and Mg release as a result of montmorillonite dissolution indicates in agreement with previous findings that under the applied conditions U(VI) is adsorbed on the edge surface of montmorillonite, which is a major mineral phase of the studied clays.

  2. Design

    DEFF Research Database (Denmark)

    Volf, Mette

    This publication is unique in its demystification and operationalization of the complex and elusive nature of the design process. The publication portrays the designer’s daily work and the creative process, which the designer is a part of. Apart from displaying the designer’s work methods...... and design parameters, the publication shows examples from renowned Danish design firms. Through these examples the reader gets an insight into the designer’s reality....

  3. Evaluation of activated carbon fiber supported nanoscale zero-valent iron for chromium (VI) removal from groundwater in a permeable reactive column.

    Science.gov (United States)

    Qu, Guangzhou; Kou, Liqing; Wang, Tiecheng; Liang, Dongli; Hu, Shibin

    2017-10-01

    An activated carbon fiber supported nanoscale zero-valent iron (ACF-nZVI) composite for Cr(VI) removal from groundwater was synthesized according to the liquid phase reduction method. The techniques of N 2 adsorption/desorption, FESEM, EDX, XRD and XPS were used to characterize the ACF-nZVI composite and the interaction between the ACF-nZVI composite and Cr(VI) ions. Batch experiments were conducted to evaluate the effects of several factors, including the amount of nZVI on activated carbon fiber (ACF), pH value, initial Cr(VI) concentration, and co-existing ions on Cr(VI) removal. The results indicate that presence of ACF can inhibit the aggregation of nanoscale zero-valent iron (nZVI) particles and increase its reactivity, and the Cr(VI) removal efficiency increases with increasing amounts of nZVI on ACF and a decrease in the initial Cr(VI) concentration. In acidic conditions, almost 100% of Cr(VI) in solution can be removed after 60 min of reaction, and the removal efficiency decreases with increasing initial pH values. The Cr(VI) removal is also dependent on the co-existing ions. Reusability experiments on ACF-nZVI demonstrate that the ACF-nZVI composite can keep a high reactivity after five successive reduction cycles. The removal mechanisms are proposed as a two-step interaction including the physical adsorption of Cr(VI) on the surface or inner layers of the ACF-nZVI composite and the subsequent reduction of Cr(VI) to Cr(III) by nZVI. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Bringing High-Rate, CO2-Based Microbial Electrosynthesis Closer to Practical Implementation through Improved Electrode Design and Operating Conditions.

    Science.gov (United States)

    Jourdin, Ludovic; Freguia, Stefano; Flexer, Victoria; Keller, Jurg

    2016-02-16

    The enhancement of microbial electrosynthesis (MES) of acetate from CO2 to performance levels that could potentially support practical implementations of the technology must go through the optimization of key design and operating conditions. We report that higher proton availability drastically increases the acetate production rate, with pH 5.2 found to be optimal, which will likely suppress methanogenic activity without inhibitor addition. Applied cathode potential as low as -1.1 V versus SHE still achieved 99% of electron recovery in the form of acetate at a current density of around -200 A m(-2). These current densities are leading to an exceptional acetate production rate of up to 1330 g m(-2) day(-1) at pH 6.7. Using highly open macroporous reticulated vitreous carbon electrodes with macropore sizes of about 0.6 mm in diameter was found to be optimal for achieving a good balance between total surface area available for biofilm formation and effective mass transfer between the bulk liquid and the electrode and biofilm surface. Furthermore, we also successfully demonstrated the use of a synthetic biogas mixture as carbon dioxide source, yielding similarly high MES performance as pure CO2. This would allow this process to be used effectively for both biogas quality improvement and conversion of the available CO2 to acetate.

  5. Operant conditioning: a minimal components requirement in artificial spiking neurons designed for bio-inspired robot's controller.

    Science.gov (United States)

    Cyr, André; Boukadoum, Mounir; Thériault, Frédéric

    2014-01-01

    In this paper, we investigate the operant conditioning (OC) learning process within a bio-inspired paradigm, using artificial spiking neural networks (ASNN) to act as robot brain controllers. In biological agents, OC results in behavioral changes learned from the consequences of previous actions, based on progressive prediction adjustment from rewarding or punishing signals. In a neurorobotics context, virtual and physical autonomous robots may benefit from a similar learning skill when facing unknown and unsupervised environments. In this work, we demonstrate that a simple invariant micro-circuit can sustain OC in multiple learning scenarios. The motivation for this new OC implementation model stems from the relatively complex alternatives that have been described in the computational literature and recent advances in neurobiology. Our elementary kernel includes only a few crucial neurons, synaptic links and originally from the integration of habituation and spike-timing dependent plasticity as learning rules. Using several tasks of incremental complexity, our results show that a minimal neural component set is sufficient to realize many OC procedures. Hence, with the proposed OC module, designing learning tasks with an ASNN and a bio-inspired robot context leads to simpler neural architectures for achieving complex behaviors.

  6. Optimization of freeze-drying condition of amikacin solid lipid nanoparticles using D-optimal experimental design.

    Science.gov (United States)

    Varshosaz, Jaleh; Ghaffari, Solmaz; Khoshayand, Mohammad Reza; Atyabi, Fatemeh; Dehkordi, Abbas Jafarian; Kobarfard, Farzad

    2012-01-01

    Amikacin as an aminoglycoside antibiotic was chosen to be loaded in a cholesterol carrier with nanoparticle size and sustained release profile to increase the dose interval of amikacin and reduce side-effects. To support the stability of solid lipid nanoparticles (SLNs), freeze-drying was suggested. Factors affecting the freeze-drying process in the present study included the type and concentration of cryoprotectants. Pre-freezing temperature effects were also studied on particle size of SLNs of amikacin. In some preliminary experiments, important factors which influenced the particle size of SLNs after lyophilization were selected and a D-optimal design was applied to optimize the freeze-drying conditions in the production of SLNs with minimum particle size growth after freeze-drying. Zeta potential, DSC thermograms, release profiles and morphology of the optimized particles were studied before and after freeze-drying. Results showed sucrose changed the particle size of SLNs of amikacin from 149 ± 4 nm to 23.9 ± 16.7 nm; in that situation, the absolute value of zeta potential changed from 1 ± 0.7 mV to 13 ± 4 mV. The release profiles showed a sustained release behavior of the loaded drug that did not change significantly before and after freeze-drying, but a burst effect was seen after it in the first 2 h. DSC analysis showed chemical interaction between amikacin and cholesterol. © 2012 Informa Healthcare USA, Inc.

  7. Removal of chromium (VI) from water by micro-alloyed aluminium ...

    African Journals Online (AJOL)

    This paper deals with Cr(VI) ion removal from water, by micro-alloyed aluminium composite (MAlC), under flow conditions. In a water environment the MAlC acts as a strong reducing agent. Dissolving it in water is accompanied by the generation of Al(III) ions and reduction of water to H2, with OH- ions. The final product is ...

  8. Hvad skal vi med skønlitteraturen?

    DEFF Research Database (Denmark)

    Bundsgaard, Jeppe; Oksbjerg, Marianne

    2012-01-01

    didaktiske læremidler, der produceres i disse år, lægges der ikke op til en udnyttelse af skønlitteraturens potentiale for at danne eleverne til demokratiske borgere. I denne artikel beskriver vi, hvad der er galt med læremidlerne. Desuden skitserer vi kriterier for formulering af elevopgaver, der lægger op...

  9. Detoxification of chromium (VI) in coastal water using lignocellulosic ...

    African Journals Online (AJOL)

    In the present study, attempts have been made to harness lignocellulosic agricultural waste material (bagasse) for the removal of chromium (VI) from highly saline coastal water used for aquacultural practices using brackish water. Five different products prepared from bagasse were evaluated for the detoxification of Cr(VI) ...

  10. Predicting chromium (VI) adsorption rate in the treatment of liquid ...

    African Journals Online (AJOL)

    The adsorption rate of chromium (VI) on commercial activated carbon during the treatment of the flocculation effluent of liquid-phase oil-based drill-cuttings has been investigated in terms of contact time and initial chromium (VI) ion concentration. Homogenizing 1 g of the activated carbon with 100 ml of the flocculation ...

  11. Moderate selenium dosing inhibited chromium (VI) toxicity in chicken liver.

    Science.gov (United States)

    Wang, Yang; Liu, Yongxia; Wan, Huiyu; Zhu, Yiran; Chen, Peng; Hao, Pan; Cheng, Ziqiang; Liu, Jianzhu

    2017-08-01

    This study aimed to clarify the effect of selenium (Se) on chromium (VI) [Cr(VI)]-induced damage in chicken liver. A total of 105 chickens were randomly divided into seven groups of 15. Group I received deionized water; group II received Cr(VI) (7.83 mg/kg/d) alone; and other groups orally received both Cr(VI) (7.83 mg/kg/d) and Se of different doses (0.14, 0.29, 0.57, 1.14, and 2.28 mg/kg/d). The levels of superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), Ca2+ -ATPase, and mitochondrial membrane potential (MMP) were measured. Results showed that Cr(VI) increased MDA content and decreased GSH content, T-SOD activity, Ca2+ -ATPase activity, and MMP level. Meanwhile, Se co-treatment (0.14, 0.29, and 0.57 mg/kg/d) increased the viability of the above indicators compared with Cr(VI)-treatment alone. In addition, histopathologic examination revealed that Cr(VI) can cause liver damage, whereas Se supplementation of moderate dose inhibited this damage. This study confirmed that Se exerted protective effect against Cr(VI)-induced liver damage. © 2017 Wiley Periodicals, Inc.

  12. Kandinsky's "Composition VI": Heideggerian Poetry in Noah's Ark

    Science.gov (United States)

    Hall, Joshua M.

    2012-01-01

    The author will begin his investigation of Wassily Kandinsky's painting "Composition VI" with Kandinsky's own commentary on the painting. He will then turn to the analysis of Kandinsky and the "Compositions" in John Sallis's book "Shades." Using this analysis as his point of departure, the author will consider how "Composition VI" resonates with…

  13. Altered corneal stromal matrix organization is associated with mucopolysaccharidosis I, III and VI.

    Science.gov (United States)

    Alroy, J; Haskins, M; Birk, D E

    1999-05-01

    The presence of cloudy corneas is a prominent feature of mucopolysaccharidosis (MPS) types I and VI, but not MPS IIIA or IIIB. The cause of corneal cloudiness in MPS I and VI is speculative. Transparency of the cornea is dependent on the uniform diameter and the regular spacing and arrangement of the collagen fibrils within the stroma. Alterations in the spacing of collagen fibrils in a variety of conditions including corneal edema, scars, and macular corneal dystrophy is clinically manifested as corneal opacity. The purpose of this study was to compare the structural organization of the stromal extracellular matrix of normal corneas with that of MPS corneas. The size and arrangement of collagen fibrils in cloudy corneas from patients with MPS I were examined. The alterations observed were an increased mean fibril diameter with a broader distribution in the MPS corneas. The MPS I corneas also had altered fibril spacing and more irregular packing compared with normal control corneas. The clear corneas of patients with MPS IIIA and IIIB also showed increases in mean fibril diameter and fibril spacing. However, there was less variation indicating more regularity than seen in MPS I. In addition, corneas from cat models of certain MPS were compared to the human corneas. Cats with MPS I and VI, as well as normal control cats, were examined. Structural alterations comparable to those seen in human MPS corneas were seen in MPS I and VI cats relative to normal clear corneas. The findings suggest that cloudy corneas in MPS I and VI are in part a consequence of structural alterations in the corneal stroma, including abnormal spacing, size, and arrangement of collagen fibrils. Copyright 1999 Academic Press.

  14. Ferrrate(VI) and freeze-thaw treatment for oxidation of hormones and inactivation of fecal coliforms in sludge.

    Science.gov (United States)

    Diak, James; Örmeci, Banu

    2017-04-01

    This study examined the individual and combined effects of potassium ferrate(VI) additions and freeze-thaw conditioning for the treatment and dewatering of wastewater sludge in cold climates, with particular focus on the inactivation of fecal coliforms and oxidation of estrogens, androgens, and progestogens. The first phase of the study evaluated the effects of potassium ferrate(VI) pre-treatment followed by freeze-thaw at -20 °C using a low (0.5 g/L) and high (5.0 g/L) dose of potassium ferrate(VI). The results showed that pre-treatment of anaerobically digested sludge with 5 g/L of potassium ferrate(VI) reduced the concentration of fecal coliforms in the sludge cake to below 100 MPN/g DS. The second phase evaluated the ability of ferrate(VI) to oxidise selected hormones in sludge. Anaerobically digested sludge samples were spiked with 10 different hormones: estrone (E1), 17α-estradiol, 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), equilin, mestranol, testosterone, norethindrone and norgestrel in two groups of low (3-75 ng/mL) and high (12-300 ng/L) concentration ranges of hormones. The samples were treated with either 0.5 or 1.0 g/L of potassium ferrate(VI), and hormone concentrations were measured again after treatment. Potassium ferrate(VI) additions as low as 1.0 g/L reduced the concentration of estrogens in sludge. Potassium ferrate(VI) additions of 0.5 and 1.0 g/L were less effective at reducing the concentrations of androgens and progestogens. Increasing ferrate(VI) dose would likely result in more substantial decreases in the concentrations of fecal coliforms and hormones. The results of this study indicate that the combined use of freeze-thaw and ferrate(VI) has the potential to provide a complete sludge treatment solution in cold regions.

  15. Museo del oro: viñetas

    Directory of Open Access Journals (Sweden)

    Les Field

    2013-01-01

    Full Text Available En enero de 2011 convocamos a un grupo internacional de académicos/activistas para discutir en Colombia las complejidades de la relación entre arqueología, excavaciones “ilícitas”, museos y comunidades indígenas desde una mirada comparativa. El taller de tres días tuvo lugar en Bogotá y Villa de Leyva. Uno de los eventos programados durante los dos días de la parte bogotana del taller fue una visita al Museo del Oro. En el restaurante del museo conversamos sobre lo que acabábamos de ver, sentir y pensar, y surgieron estas impresiones en las que el estupor convive con un fuerte deseo por decir algo. En Villa de Leyva nació la idea de que cada uno de nosotros transcribiera sus emociones en formato de viñeta.

  16. A Video Tour through ViSta 6.4

    Directory of Open Access Journals (Sweden)

    J. Gabriel Molina

    2004-12-01

    Full Text Available This paper offers a visual tour throughout ViSta 6.4, a freeware statistical program based on Lisp-Stat and focused on techniques for statistical visualization (Young 2004. This travel around ViSta is based on screen recordings that illustrate the main features of the program in action. The following aspects of ViSta 6.4 are displayed: the program's interface (ViSta's desktop, menubar and pop-up menus, help system; its data management capabilities (data input and editing, data transformations; features associated to data analysis (data description, statistical modeling; and the options for Lisp-Stat development in ViSta. The video recordings associated to this tour (.wmv files can be visualized at http://www.jstatsoft.org/v13/i08/ using the Internet Explorer navigator, or by clicking on the figures in the paper.

  17. Biosorption of uranium (VI) by immobilized Aspergillus fumigatus beads

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jingsong, E-mail: xhwjs@163.co [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China) and Hunan Key Laboratory of Pollution Control and Resource Reuse, University of South China, Henyang, Hunan 421001 (China); Hu Xinjiang [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China); College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Liu Yunguo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Xie Shuibo [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China); Hunan Key Laboratory of Pollution Control and Resource Reuse, University of South China, Henyang, Hunan 421001 (China); Bao Zhenglei [School of Urban Construction, University of South China, 28 West Changsheng Road, Hengyang, Hunan 421001 (China)

    2010-06-15

    Biosorption of uranium (VI) ions by immobilized Aspergillus fumigatus beads was investigated in a batch system. The influences of solution pH, biosorbent dose, U (VI) concentration, and contact time on U (VI) biosorption were studied. The results indicated that the adsorption capacity was strongly affected by the solution pH, the biosorbent dose and initial U (VI) concentration. Optimum biosorption was observed at pH 5.0, biosrobent dose (w/v) 2.5%, initial U (VI) concentration 60 mg L{sup -1}. Biosorption equilibrium was established in 120 min. The adsorption process conformed to the Freunlich and Temkin isothermal adsorption models. The dynamic adsorption model conformed to pseudo-second order model.

  18. Application of computational fluid dynamics and pedestrian-behavior simulations to the design of task-ambient air-conditioning systems of a subway station

    Energy Technology Data Exchange (ETDEWEB)

    Fukuyo, Kazuhiro [Graduate School of Innovation and Technology Management, Faculty of Engineering, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi 755-8611 (Japan)

    2006-04-15

    The effects of task-ambient (TA) air-conditioning systems on the air-conditioning loads in a subway station and the thermal comfort of passengers were studied using computational fluid dynamics (CFD) and pedestrian-behavior simulations. The pedestrian-behavior model was applied to a standard subway station. Task areas were set up to match with crowdedness as predicted by the pedestrian-behavior simulations. Subsequently, a variety of TA air-conditioning systems were designed to selectively control the microclimate of the task areas. Their effects on the thermal environment in the station in winter were predicted by CFD. The results were compared with those of a conventional air-conditioning system and evaluated in relation to the thermal comfort of subway users and the air-conditioning loads. The comparison showed that TA air-conditioning systems improved thermal comfort and decreased air-conditioning loads. (author)

  19. Investigation of uranium (VI) adsorption by polypyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Abdi, S. [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Nasiri, M., E-mail: mnasiri@semnan.ac.ir [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Mesbahi, A. [Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Khani, M.H. [Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, 14395-836 (Iran, Islamic Republic of)

    2017-06-15

    Highlights: • The adsorbent (polypyrrole) was synthesized by a chemical method using PEG, DBSNa and CTAB as the surfactant. • The solution pH was one of the most important parameters affecting the adsorption of uranium. • The CTAB provided higher removal percentage compared with the other surfactants. • The maximum adsorption capacity obtained from Langmuir isotherm was 87.72 mg/g. • The pseudo second-order model fitted well with the adsorption kinetic of polypyrrole to uranium. - Abstract: The purpose of this study was to investigate the adsorption of uranium (VI) ions on the polypyrrole adsorbent. Polypyrrole was synthesized by a chemical method using polyethylene glycol, sodium dodecylbenzenesulfonate, and cetyltrimethylammonium bromide as the surfactant and iron (III) chloride as an oxidant in the aqueous solution. The effect of various surfactants on the synthesized polymers and their performance as the uranium adsorbent were investigated. Adsorbent properties were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The effect of different parameters such as pH, contact time, initial metal ion concentrations, adsorbent dose, and the temperature was investigated in the batch system for uranium adsorption process. It has been illustrated that the adsorption equilibrium time is 7 min. The results showed that the Freundlich model had the best agreement and the maximum adsorption capacity of polypyrrole for uranium (VI) was determined 87.72 mg/g from Langmuir isotherm. In addition, the mentioned adsorption process was fast and the kinetic data were fitted to the Pseudo first and second order models. The adsorption kinetic data followed the pseudo-second-order kinetic model. Moreover, the thermodynamic parameters ΔG{sup 0}, ΔH{sup 0} and ΔS{sup 0} showed that the uranium adsorption process by polypyrrole was endothermic and spontaneous.

  20. Plutonium(V/VI) Reduction by the Metal-Reducing Bacteria Geobacter metallireducens GS-15 and Shewanella oneidensis MR-1▿

    Science.gov (United States)

    Icopini, Gary A.; Lack, Joe G.; Hersman, Larry E.; Neu, Mary P.; Boukhalfa, Hakim

    2009-01-01

    We examined the ability of the metal-reducing bacteria Geobacter metallireducens GS-15 and Shewanella oneidensis MR-1 to reduce Pu(VI) and Pu(V). Cell suspensions of both bacteria reduced oxidized Pu [a mixture of Pu(VI) and Pu(V)] to Pu(IV). The rate of plutonium reduction was similar to the rate of U(VI) reduction obtained under similar conditions for each bacteria. The rates of Pu(VI) and U(VI) reduction by cell suspensions of S. oneidensis were slightly higher than the rates observed with G. metallireducens. The reduced form of Pu was characterized as aggregates of nanoparticulates of Pu(IV). Transmission electron microscopy images of the solids obtained from the cultures after the reduction of Pu(VI) and Pu(V) by S. oneidensis show that the Pu precipitates have a crystalline structure. The nanoparticulates of Pu(IV) were precipitated on the surface of or within the cell walls of the bacteria. The production of Pu(III) was not observed, which indicates that Pu(IV) was the stable form of reduced Pu under these experimental conditions. Experiments examining the ability of these bacteria to use Pu(VI) as a terminal electron acceptor for growth were inconclusive. A slight increase in cell density was observed for both G. metallireducens and S. oneidensis when Pu(VI) was provided as the sole electron acceptor; however, Pu(VI) concentrations decreased similarly in both the experimental and control cultures. PMID:19363069

  1. Ultra-trace recognition and removal of toxic chromium (VI) ions from water using visual mesocaptor.

    Science.gov (United States)

    Shenashen, Md A; Shahat, A; El-Safty, Sherif A

    2013-01-15

    The key to designing optical mesocaptors is to construct a chromogenic receptor, namely, diphenylcarbazide (DPC), as a nanoscale platform scavenger with different functional characteristics, such as density, accessibility, and intrinsic mobility. Engineering of optical captors allows facile and reliable signaling in continuous monitoring modes, and enables simple and high-speed removal of toxic chromium (VI) ions. Mesoporous aluminosilica monoliths, with unique morphologies, active surface sites, and physical properties, enhance sensing/removal characteristics in terms of sensitivity, selectivity, and response time. The systematic design of optical mesocaptor is based on a densely patterned selective binding site (DPC) in engineered mesocylinder carriers that have multidirectional pores and microsized particle-like monoliths to control the adsorption/detection assays of Cr(VI) ions. Synthetic mesocaptor can be used for visual removal of Cr(VI) ions even at low concentration levels of 10(-10)M (i.e., 0.07 ppb) with rapid response time in minutes. Moreover, these new classes of design-made hybrid mesocaptor exhibit long-term signaling stability and recognition functionalities that provided extraordinary sensitivity, selectivity, reusability, and fast kinetic detection and quantification of various deleterious metal ions in the environment. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Design, installation, and condition assessment of a concrete bridge deck constructed with ASTM A1035 CS no. 4 bars.

    Science.gov (United States)

    2017-06-01

    Recently developed corrosion-resistant reinforcing structural design guidelines were used to design, construct, and : assess a reinforced concrete bridge deck with high-strength ASTM A1035 CS steel bars. The bridge replacement is located : along the ...

  3. Vertical flow-constructed wetlands for domestic wastewater treatment under tropical conditions: effect of different design and operational parameters.

    Science.gov (United States)

    Bohórquez, Eliana; Paredes, Diego; Arias, Carlos Alberto

    2017-01-01

    This study assessed the treatment of domestic wastewater to find the optimum vertical flow-constructed wetland (VFCW) configuration under tropical conditions. Eight pilot-scale configurations units were studied to compare between fine sand and medium gravel used as substrate, two feeding frequencies (20 pulses d-1 and 10 pulses d-1), and the presence or absence of tropical plants (Heliconia psittacorum). The results showed that the sand beds were significantly more efficient in the removal of organic matter, ammonia nitrogen, and total suspended solids than gravel beds, presenting average removal rates of 48 and 24 g m-2 d-1 of COD; 35 and 16 g m-2 d-1 of BOD5; 7 and 4 g m-2 d-1 of [Formula: see text]; 9 and 0 g m-2 d-1 for sand and gravel, respectively. The oxygen consumption rates were calculated and a value of 65 g m-2 d-1 was obtained for sand beds while for the gravel beds the consumption rate was 30 g m-2 d-1. The assessment of different kinds of nitrogen showed interesting dynamics in the nitrification processes. The presence of H. psittacorum showed positive effects in the total nitrogen (TN) removal. The different loading frequencies applied did not show significant statistical differences in the removal of the tested contaminants. Preliminary results were found in the pathogen removal, where the sand is favorable as the substrate. This work represents the first step in the research of optimum VFWC design and operation parameters for Colombia as well as the use of plants of the genus Heliconia.

  4. Design of a Fractional Order Phase Shaper for Iso-Damped Control of a PHWR Under Step-Back Condition

    Science.gov (United States)

    Saha, Suman; Das, Saptarshi; Ghosh, Ratna; Goswami, Bhaswati; Balasubramanian, R.; Chandra, A. K.; Das, Shantanu; Gupta, Amitava

    2010-06-01

    Phase shaping using fractional order (FO) phase shapers has been proposed by many contemporary researchers as a means of producing systems with iso-damped closed loop response due to a stepped variation in input. Such systems, with the closed loop damping remaining invariant to gain changes can be used to produce dead-beat step response with only rise time varying with gain. This technique is used to achieve an active step-back in a Pressurized Heavy Water Reactor (PHWR) where it is desired to change the reactor power to a pre-determined value within a short interval keeping the power undershoot as low as possible. This paper puts forward an approach as an alternative for the present day practice of a passive step-back mechanism where the control rods are allowed to drop during a step-back action by gravity, with release of electromagnetic clutches. The reactor under a step-back condition is identified as a system using practical test data and a suitable Proportional plus Integral plus Derivative (PID) controller is designed for it. Then the combined plant is augmented with a phase shaper to achieve a dead-beat response in terms of power drop. The fact that the identified static gain of the system depends on the initial power level at which a step-back is initiated, makes this application particularly suited for using a FO phase shaper. In this paper, a model of a nuclear reactor is developed for a control rod drop scenario involving rapid power reduction in a 500 MWe Canadian Deuterium Uranium (CANDU) reactor using AutoRegressive Exogenous (ARX) algorithm. The system identification and reduced order modeling are developed from practical test data. For closed loop active control of the identified reactor model, the fractional order phase shaper along with a PID controller is shown to perform better than the present Reactor Regulating System (RRS) due to its iso-damped nature.

  5. Biosorption of Cr(VI) and As(V) at high concentrations by organic and inorganic wastes

    Science.gov (United States)

    María Rivas Pérez, Ivana; Paradelo Núñez, Remigio; Nóvoa Muñoz, Juan Carlos; Arias Estévez, Manuel; José Fernández Sanjurjo, María; Álvarez Rodríguez, Esperanza; Núñez Delgado, Avelino

    2016-04-01

    The potential reutilization of several wastes as biosorbents for As(V) and Cr(VI) has been assessed in batch-type experiments. The materials studied were one inorganic: mussel shell, and three organic: pine bark, oak ash and hemp waste. Batch experiments were performed in order to determine the removal capacity of the wastes under conditions of high As(V) and Cr(VI) loads. For this, 3 g of each waste material were added with 30 mL NaNO3 0.01 M dissolutions containing 0, 0.5, 1.5, 3 and 6 mmol As(V) L-1 or Cr(VI) L-1, prepared from analytical grade Na2HAsO4 or K2Cr2O7. The resulting suspensions were shaken for 24 h, centrifuged and filtered. Once each batch experiment corresponding to the sorption trials ended, each individual sample was added with 30 mL of NaNO3 0.01 M to desorb As(V) or Cr(VI), shaken for 24 h, centrifuged and filtered as in the sorption trials. Oak ash showed high sorption (>76%) and low desorption (hemp waste (98%) with very low desorption (hemp waste and mussel shell, that presented very low Cr(VI) sorption (<10%). Sorption data for both elements were better described by the Freundlich than by the Langmuir model. The variable results obtained for the removal of the two anionic contaminants for a given sorbent suggest that different mechanisms govern removal from the solution in each case. In summary, oak ash would be an efficient sorbent material for As(V), but not for Cr(VI), while pine bark would be the best sorbent for Cr(VI) removal.

  6. Surface complexation modeling of U(VI) adsorption by aquifer sediments from a former mill tailings site at Rifle, Colorado

    Science.gov (United States)

    Hyun, S.P.; Fox, P.M.; Davis, J.A.; Campbell, K.M.; Hayes, K.F.; Long, P.E.

    2009-01-01

    A study of U(VI) adsorption by aquifer sediment samples from a former uranium mill tailings site at Rifle, Colorado, was conducted under oxic conditions as a function of pH, U(VI), Ca, and dissolved carbonate concentration. Batch adsorption experiments were performed using <2mm size sediment fractions, a sand-sized fraction, and artificial groundwater solutions prepared to simulate the field groundwater composition. To encompass the geochemical conditions of the alluvial aquifer at the site, the experimental conditions ranged from 6.8 ?? 10-8 to 10-5 M in [U(VI)]tot, 7.2 to 8.0 in pH, 3.0 ?? 10-3 to 6.0 ?? 10 -3 M in [Ca2+], and 0.05 to 2.6% in partial pressure of carbon dioxide. Surface area normalized U(VI) adsorption Kd values for the sand and <2 mm sediment fraction were similar, suggesting a similar reactive surface coating on both fractions. A two-site two-reaction, nonelectrostatic generalized composite surface complexation model was developed and successfully simulated the U(VI) adsorption data. The model successfully predicted U(VI) adsorption observed from a multilevel sampling well installed at the site. A comparison of the model with the one developed previously for a uranium mill tailings site at Naturita, Colorado, indicated that possible calcite nonequilibrium of dissolved calcium concentration should be evaluated. The modeling results also illustrate the importance of the range of data used in deriving the best fit model parameters. ?? 2009 American Chemical Society.

  7. Analytical display design for flight tasks conducted under instrument meteorological conditions. [human factors engineering of pilot performance for display device design in instrument landing systems

    Science.gov (United States)

    Hess, R. A.

    1976-01-01

    Paramount to proper utilization of electronic displays is a method for determining pilot-centered display requirements. Display design should be viewed fundamentally as a guidance and control problem which has interactions with the designer's knowledge of human psychomotor activity. From this standpoint, reliable analytical models of human pilots as information processors and controllers can provide valuable insight into the display design process. A relatively straightforward, nearly algorithmic procedure for deriving model-based, pilot-centered display requirements was developed and is presented. The optimal or control theoretic pilot model serves as the backbone of the design methodology, which is specifically directed toward the synthesis of head-down, electronic, cockpit display formats. Some novel applications of the optimal pilot model are discussed. An analytical design example is offered which defines a format for the electronic display to be used in a UH-1H helicopter in a landing approach task involving longitudinal and lateral degrees of freedom.

  8. The FUSE Survey of 0 VI in the Galactic Halo

    Science.gov (United States)

    Sonneborn, George; Savage, B. D.; Wakker, B. P.; Sembach, K. R.; Jenkins, E. B.; Moos, H. W.; Shull, J. M.

    2003-01-01

    This paper summarizes the results of the Far-Ultraviolet Spectroscopic Explorer (FUSE) program to study 0 VI in the Milky Way halo. Spectra of 100 extragalactic objects and two distant halo stars are analyzed to obtain measures of O VI absorption along paths through the Milky Way thick disk/halo. Strong O VI absorption over the velocity range from -100 to 100 km/s reveals a widespread but highly irregular distribution of O VI, implying the existence of substantial amounts of hot gas with T approx. 3 x 10(exp 5) K in the Milky Way thick disk/halo. The overall distribution of O VI is not well described by a symmetrical plane-parallel layer of patchy O VI absorption. The simplest departure from such a model that provides a reasonable fit to the observations is a plane-parallel patchy absorbing layer with an average O VI mid-plane density of n(sub 0)(O VI) = 1.7 x 10(exp -2)/cu cm, a scale height of approx. 2.3 kpc, and a approx. 0.25 dex excess of O VI in the northern Galactic polar region. The distribution of O VI over the sky is poorly correlated with other tracers of gas in the halo, including low and intermediate velocity H I, Ha emission from the warm ionized gas at approx. l0(exp 4) K, and hot X-ray emitting gas at approx. l0(exp 6) K . The O VI has an average velocity dispersion, b approx. 60 km/s and standard deviation of 15 km/s. Thermal broadening alone cannot explain the large observed profile widths. A combination of models involving the radiative cooling of hot fountain gas, the cooling of supernova bubbles in the halo, and the turbulent mixing of warm and hot halo gases is required to explain the presence of O VI and other highly ionized atoms found in the halo. The preferential venting of hot gas from local bubbles and superbubbles into the northern Galactic polar region may explain the enhancement of O VI in the North.

  9. IN VITRO Cr(VI SPECIATION IN SYNTHETIC SALIVA AFTER RELEASING FROM ORTHODONTIC BRACKETS USING SILICA-APTES SEPARATION AND GF AAS DETERMINATION

    Directory of Open Access Journals (Sweden)

    Maciel S. Luz

    Full Text Available A method for Cr(VI speciation in synthetic saliva after releasing from orthodontic brackets, using silica nanoparticles organofunctionalized with (3-aminopropyltriethoxysilane (APTES for Cr(III/Cr(VI separation and GF AAS determination is proposed. Under the optimized conditions, Cr(VI speciation was performed using 150 mg of silica organofunctionalized with 2.0% (v v-1 of APTES at pH 8. It was observed different sensitivity when calibrations of GF AAS were performed using Cr(III or Cr(VI as standard solutions. Consequently, calibrations using stoichiometric mixtures (Cr(III + Cr(VI were used for total Cr determination and calibration using Cr(VI was used only for the determination of this specie. The reliability of the proposed silica-APTES separation procedure and GF AAS determination was checked by addition of both species in synthetic saliva. Recoveries ranging from 97 to 110% were obtained. The repeatability, based on the relative standard deviation (RSD inter days was less than 6%. A corrosion test was carried out on 20 orthodontic brackets from two different models, after immersion in synthetic saliva (pH=6.0 at 37 °C with agitation (125 rpm for 24 h. It was observed that about 40% of the total chromium released from the analyzed orthodontic brackets was Cr(VI.

  10. Phosphate solubilization and chromium (VI) remediation potential of Klebsiella sp. strain CPSB4 isolated from the chromium contaminated agricultural soil.

    Science.gov (United States)

    Gupta, Pratishtha; Kumar, Vipin; Usmani, Zeba; Rani, Rupa; Chandra, Avantika

    2018-02-01

    In this study, an effort was made to identify an efficient phosphate solubilizing bacterial strain from chromium contaminated agricultural soils. Based on the formation of a solubilized halo around the colonies on Pikovskaya's agar amended with chromium (VI), 10 strains were initially screened out. Out of 10, strain CPSB4, which showed significantly high solubilization zone at different chromium concentrations, was selected for further study. The strain CPSB4 showed significant plant growth promotion traits with chromium (VI) stress under in-vitro conditions in broth. The plant growth promotion activities of the strain decreased regularly, but were not completely lost with the increase in concentration of chromium up to 200 mg L(-1). On subjected to FT-IR analysis, the presence of the functional group, indicating the organic acid aiding in phosphate solubilization was identified. At an optimal temperature of 30 (°)C and pH 7.0, the strain showed around 93% chromium (VI) reduction under in-vitro conditions in broth study. In soil condition, the maximum chromium (VI) reduction obtained was 95% under in-vitro conditions. The strain CPSB4 was identified as Klebsiella sp. on the basis of morphological, biochemical and 16S rRNA gene sequencing. This study shows that the diverse role of the bacterial strain CPSB4 would be useful in the chromium contaminated soil as a good bioremediation and plant growth promoting agent as well. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. 78 FR 27982 - U.S. Flag Compliance With MARPOL Annex VI International Energy Efficiency (IEE) Requirements

    Science.gov (United States)

    2013-05-13

    ... SECURITY Coast Guard U.S. Flag Compliance With MARPOL Annex VI International Energy Efficiency (IEE... issuance of an International Energy Efficiency Certificate and the preparation of a Ship Energy Efficiency... Energy Efficiency Design Index. These requirements apply to all U.S. flag ships 400 gross tonnage and...

  12. Investigation on Microbial Dissolution of Uranium (VI) from Autunite Mineral - 13421

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda, Paola; Katsenovich, Yelena; Lagos, Leonel [Applied Research Center, Florida International University. 10555 West Flagler St. Suite 2100, Miami Fl 33175 (United States)

    2013-07-01

    Precipitating autunite minerals by polyphosphate injection was identified as a feasible remediation strategy for sequestering uranium in contaminated groundwater and soil in situ at the Hanford Site. Autunite stability under vadose and saturated zone environmental conditions can help to determine the long-term effectiveness of this remediation strategy. The Arthrobacter bacteria are one of the most common groups in soils and are found in large numbers in Hanford soil as well as other subsurface environments contaminated with radionuclides. Ubiquitous in subsurface microbial communities, these bacteria can play a significant role in the dissolution of minerals and the formation of secondary minerals. The main objective of this investigation was to study the bacterial interactions under oxidizing conditions with uranium (VI); study the potential role of bicarbonate, which is an integral complexing ligand for U(VI) and a major ion in groundwater compositions; and present data from autunite dissolution experiments using Arthrobacter strain G968, a less U(VI)-tolerant strain. Sterile 100 mL glass mixed reactors served as the major bioreactor for initial experimentation. These autunite-containing bioreactors were injected with bacterial cells after the autunite equilibrated with the media solution amended with 0 mM, 3 mM 5 mM and 10 mM concentrations of bicarbonate. G968 Arthrobacter cells in the amount of 10{sup 6} cells/mL were injected into the reactors after 27 days, giving time for the autunite to reach steady state. Abiotic non-carbonate controls were kept without bacterial inoculation to provide a control for the biotic samples. Samples of the solution were analyzed for dissolved U(VI) by means of kinetic phosphorescence analyzer KPA-11 (Chemcheck Instruments, Richland, WA). Analysis showed that as [HCO{sub 3}{sup -}] increases, a diminishing trend on the effect of bacteria on autunite leaching is observed. Viability of cells was conducted after 24 hours of cell

  13. Melanin-embedded materials effectively remove hexavalent chromium (CrVI) from aqueous solution.

    Science.gov (United States)

    Cuong, An Manh; Le Na, Nguyen Thi; Thang, Pham Nhat; Diep, Trinh Ngoc; Thuy, Ly Bich; Thanh, Nguyen Lai; Thang, Nguyen Dinh

    2018-02-23

    Currently, it is recognized that water polluted with toxic heavy metal ions may cause serious effects on human health. Therefore, the development of new materials for effective removal of heavy metal ions from water is still a widely important area. Melanin is being considered as a potential material for removal of heavy metal from water. In this study, we synthesized two melanin-embedded beads from two different melanin powder sources and named IMB (Isolated Melanin Bead originated from squid ink sac) and CMB (Commercial Melanin Bead originated from sesame seeds). These beads were of globular shape and 2-3 mm in diameter. We investigated and compared the sorption abilities of these two bead materials toward hexavalent-chromium (Cr VI ) in water. The isotherm sorption curves were established using Langmuir and Freundlich models in the optimized conditions of pH, sorption time, solid/liquid ratio, and initial concentration of Cr VI . The FITR analysis was also carried out to show the differences in surface properties of these two beads. The optimized conditions for isotherm sorption of Cr VI on IMB/CMB were set at pH values of 2/2, sorption times of 90/300 min, and solid-liquid ratios of 10/20 mg/mL. The maximum sorption capacities calculated based on the Langmuir model were 19.60 and 6.24 for IMB and CMB, respectively. However, the adsorption kinetic of Cr VI on the beads fitted the Freundlich model with R 2 values of 0.992 for IMB and 0.989 for CMB. The deduced Freundlich constant, 1/n, in the range of 0.2-0.8 indicated that these beads are good adsorption materials. In addition, structure analysis data revealed great differences in physical and chemical properties between IMB and CMB. Interestingly, FTIR analysis results showed strong signals of -OH (3295.35 cm - 1 ) and -C=O (1608.63 cm - 1 ) groups harboring on the IMB but not CMB. Moreover, loading of Cr VI on the IMB caused a shift of broad peaks from 3295.35 cm - 1 and 1608.63 cm - 1 to 3354

  14. Removal of chromium from Cr(VI) polluted wastewaters by reduction with scrap iron and subsequent precipitation of resulted cations.

    Science.gov (United States)

    Gheju, M; Balcu, I

    2011-11-30

    This work presents investigations on the total removal of chromium from Cr(VI) aqueous solutions by reduction with scrap iron and subsequent precipitation of the resulted cations with NaOH. The process was detrimentally affected by a compactly passivation film occurred at scrap iron surface, mainly composed of Cr(III) and Fe(III). Maximum removal efficiency of the Cr(total) and Fe(total) achieved in the clarifier under circumneutral and alkaline (pH 9.1) conditions was 98.5% and 100%, respectively. The optimum precipitation pH range which resulted from this study is 7.6-8.0. Fe(total) and Cr(total) were almost entirely removed in the clarifier as Fe(III) and Cr(III) species; however, after Cr(VI) breakthrough in column effluent, chromium was partially removed in the clarifier also as Cr(VI), by coprecipitation with cationic species. As long the column effluent was free of Cr(VI), the average Cr(total) removal efficiency of the packed column and clarifier was 10.8% and 78.8%, respectively. Our results clearly indicated that Cr(VI) contaminated wastewater can be successfully treated by combining reduction with scrap iron and chemical precipitation with NaOH. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Evaluation of the bioremoval of Cr(VI) and TOC in biofilters under continuous operation using response surface methodology.

    Science.gov (United States)

    Leles, Daniela M A; Lemos, Diego A; Filho, Ubirajara C; Romanielo, Lucienne L; de Resende, Miriam M; Cardoso, Vicelma L

    2012-06-01

    In the present study, the bioremoval of Cr(VI) and the removal of total organic carbon (TOC) were achieved with a system composed by an anaerobic filter and a submerged biofilter with intermittent aeration using a mixed culture of microorganisms originating from contaminated sludge. In the aforementioned biofilters, the concentrations of chromium, carbon, and nitrogen were optimized according to response surface methodology. The initial concentration of Cr(VI) was 137.35 mg l(-1), and a bioremoval of 85.23% was attained. The optimal conditions for the removal of TOC were 4 to 8 g l(-1) of sodium acetate, >0.8 g l(-1) of ammonium chloride and 60 to 100 mg l(-1) of Cr(VI). The results revealed that ammonium chloride had the strongest effect on the TOC removal, and 120 mg l(-1) of Cr(VI) could be removed after 156 h of operation. Moreover, 100% of the Cr(VI) and the total chromium content of the aerobic reactor output were removed, and TOC removals of 80 and 87% were attained after operating the anaerobic and aerobic reactors for 130 and 142 h, respectively. The concentrations of cells in both reactors remained nearly constant over time. The residence time distribution was obtained to evaluate the flow through the bioreactors.

  16. Removal of chromium (VI) ions from aqueous solution by adsorption onto two marine isolates of Yarrowia lipolytica

    Energy Technology Data Exchange (ETDEWEB)

    Bankar, Ashok V.; Kumar, Ameeta R. [Institute of Bioinformatics and Biotechnology, University of Pune, Pune 411 007 (India); Zinjarde, Smita S., E-mail: smita@unipune.ernet.in [Institute of Bioinformatics and Biotechnology, University of Pune, Pune 411 007 (India)

    2009-10-15

    The removal of chromium (VI) ions from aqueous solutions by the biomass of two marine strains of Yarrowia lipolytica (NCIM 3589 and 3590) was studied with respect to pH, temperature, biomass, sea salt concentration, agitation speed, contact time and initial concentration of chromium (VI) ions. Maximum biosorption was observed at pH 1.0 and at a temperature of 35 deg. C. Increase in biomass and sea salts resulted in a decreased metal uptake. With an agitation speed of 130 rpm, equilibrium was attained within 2 h. Under optimum conditions, biosorption was enhanced with increasing concentrations of Cr (VI) ions. NCIM 3589 and 3590 displayed a specific uptake of Cr (VI) ions of 63.73 {+-} 1.3 mg g{sup -1} at a concentration of 950 ppm and 46.09 {+-} 0.23 mg g{sup -1} at 955 ppm, respectively. Scatchard plot analysis revealed a straight line allowing the data to be fitted in the Langmuir model. The adsorption data obtained also fitted well to the Freundlich isotherm. The surface sequestration of Cr (VI) by Y. lipolytica was investigated with a scanning electron microscope equipped with an energy dispersive spectrometer (SEM-EDS) as well as with ED-X-ray fluorescence (ED-XRF). Fourier transform infrared (FTIR) spectroscopy revealed the involvement of carboxyl, hydroxyl and amide groups on the cell surfaces in chromium binding.

  17. Factors influencing U(VI adsorption onto soil from a candidate very low level radioactive waste disposal site in China

    Directory of Open Access Journals (Sweden)

    Zuo Rui

    2016-01-01

    Full Text Available The properties of soil at disposal sites are very important for geological disposal of very low level radioactive waste in terms of U(VI. In this study, soil from a candidate very low level radioactive waste disposal site in China was evaluated for its capacity on uranium sorption. Specifically, the equilibrium time, initial concentration, soil particle, pH, temperature, and carbonate were evaluated. The results indicated that after 15-20 days of sorption, the Kd value fluctuated and stabilized at 355-360 mL/g. The adsorptive capacity of uranium was increased as the initial uranium concentration increased, while it decreased as the soil particle size increased. The pH value played an important role in the U(VI sorption onto soil, especially under alkaline conditions, and had a great effect on the sorption capacity of soil for uranium. Moreover, the presence of carbonate decreased the sorption of U(VI onto soil because of the role of the strong complexation of carbonate with U(VI in the groundwater. Overall, this study assessed the behavior of U(VI sorption onto natural soil, which would be an important factor in the geological barrier of the repository, has contribution on mastering the characteristic of the adsorption of uranium in the particular soil media for the process of very low level radioactive waste disposal.

  18. Neptunium(V) and neptunium(VI) solubilities in synthetic brines of interest to the Waste Isolation Pilot Plant (WIPP)

    Energy Technology Data Exchange (ETDEWEB)

    Novak, C.F. [Sandia National Labs., Albuquerque, NM (United States); Nitsche, H. [Lawrence Berkeley National Lab., CA (United States). Earth Sciences Div.]|[Forschungszentrum Rossendorf e.V., Dresden (Germany). Inst. fuer Radiochemie; Silber, H.B. [Lawrence Berkeley National Lab., CA (United States). Earth Sciences Div.]|[San Jose State Univ., CA (United States). Chemistry Dept.] [and others

    1996-12-31

    The solubility of Np(V) and Np(VI) has been measured in three synthetic Na-K-Mg-Cl brines in the presence of CO{sub 2}(g). Experiments were prepared from oversaturation by adding an excess of NpO{sub 2}{sup +} or NpO{sub 2}{sup 2+} to the brines and allowing the neptunium solids to precipitate. Vessels were maintained in contact with fixed CO{sub 2}(g) partial pressures at constant pH and 24 {+-} 1 C. Dissolved Np(V) concentrations decreased several orders of magnitude within the first 100 days of the experiment, while dissolved Np(VI) concentrations decreased initially but then remained relatively constant for more than 400 days. The solid phases formed in all experiments were identified by X-ray powder diffraction as KNpO{sub 2}CO{sub 3}{center_dot}xH{sub 2}O(s). Steady state concentrations for Np(V) are similar to those observed for Pu(V) in the same brines under the same conditions, where Pu occurs predominantly as Pu(V). Similarly, steady state concentrations for Np(VI), which was not reduced over a two year period, compare well with measured Pu(VI) concentrations in the same brines before the Pu(VI) was reduced to Pu(V).

  19. The WMO RA VI Regional Climate Centre Network - a support to users in Europe

    Science.gov (United States)

    Rösner, S.

    2012-04-01

    deliver better climate services to national users. On 1 June 2009 the WMO RA VI Pilot RCC-Network started its pilot phase to demonstrate its capability to provide, on an operational day-to-day basis, the products agreed upon by the member countries of RA VI. On 5 October 2011 the process to become formally designated WMO RA VI RCC-Network was initiated, and it is expected that the designation will happen mid to end 2012. The presentation will describe the global and regional activities related to RCCs and explain in more details the situation in WMO RA VI (Europe).

  20. Investigation of run-off and stability conditions and design of mitigation measures in Kittelfjøll, Sweden

    Science.gov (United States)

    Lundström, K.; Fallsvik, J.; Andersson, M.

    2009-04-01

    during heavy summer storms and that the meadows below the slopes are built-up by alluvial masses. During the latest large incident, which happened in 1912, according to local people the local main-road was cut-off and huge amount of material was transported and spread far and wide over the meadows. In that time, however, only handful minor farms existed in the area. The field investigation in 2008 included investigation of the brooks, investigations of wet sections, traces from earlier events, the amount of transportable material available to be carried by debris flows, run-out lengths and assessment of catchment areas and run-off conditions. Based on the field investigation and determination of design precipitation, hazard maps were constructed, preventive measures were suggested and restrictions were given. The preventive measures compile construction of sedimentation dams in the top of the alluvial fans and canalisation of the creeks below. The restrictions consist of buffer zones along the brooks, areas where dwellings should be avoided and forest control plans and yearly erosion inspections. This type of investigation had only been performed once earlier in Sweden which was done by SGI in Åre in 2003.

  1. Optimal experimental design for improving the estimation of growth parameters of Lactobacillus viridescens from data under non-isothermal conditions.

    Science.gov (United States)

    Longhi, Daniel Angelo; Martins, Wiaslan Figueiredo; da Silva, Nathália Buss; Carciofi, Bruno Augusto Mattar; de Aragão, Gláucia Maria Falcão; Laurindo, João Borges

    2017-01-02

    In predictive microbiology, the model parameters have been estimated using the sequential two-step modeling (TSM) approach, in which primary models are fitted to the microbial growth data, and then secondary models are fitted to the primary model parameters to represent their dependence with the environmental variables (e.g., temperature). The Optimal Experimental Design (OED) approach allows reducing the experimental workload and costs, and the improvement of model identifiability because primary and secondary models are fitted simultaneously from non-isothermal data. Lactobacillus viridescens was selected to this study because it is a lactic acid bacterium of great interest to meat products preservation. The objectives of this study were to estimate the growth parameters of L. viridescens in culture medium from TSM and OED approaches and to evaluate both the number of experimental data and the time needed in each approach and the confidence intervals of the model parameters. Experimental data for estimating the model parameters with TSM approach were obtained at six temperatures (total experimental time of 3540h and 196 experimental data of microbial growth). Data for OED approach were obtained from four optimal non-isothermal profiles (total experimental time of 588h and 60 experimental data of microbial growth), two profiles with increasing temperatures (IT) and two with decreasing temperatures (DT). The Baranyi and Roberts primary model and the square root secondary model were used to describe the microbial growth, in which the parameters b and Tmin (±95% confidence interval) were estimated from the experimental data. The parameters obtained from TSM approach were b=0.0290 (±0.0020) [1/(h(0.5)°C)] and Tmin=-1.33 (±1.26) [°C], with R(2)=0.986 and RMSE=0.581, and the parameters obtained with the OED approach were b=0.0316 (±0.0013) [1/(h(0.5)°C)] and Tmin=-0.24 (±0.55) [°C], with R(2)=0.990 and RMSE=0.436. The parameters obtained from OED approach

  2. Molecular modeling of directed self-assembly of block copolymers: Fundamental studies of processing conditions and evolutionary pattern design

    Science.gov (United States)

    Khaira, Gurdaman Singh

    Rapid progress in the semi-conductor industry has pushed for smaller feature sizes on integrated electronic circuits. Current photo-lithographic techniques for nanofabrication have reached their technical limit and are problematic when printing features small enough to meet future industrial requirements. "Bottom-up'' techniques, such as the directed self-assembly (DSA) of block copolymers (BCP), are the primary contenders to compliment current "top-down'' photo-lithography ones. For industrial requirements, the defect density from DSA needs to be less than 1 defect per 10 cm by 10 cm. Knowledge of both material synthesis and the thermodynamics of the self-assembly process are required before optimal operating conditions can be found to produce results adequate for industry. The work present in this thesis is divided into three chapters, each discussing various aspects of DSA as studied via a molecular model that contains the essential physics of BCP self-assembly. Though there are various types of guiding fields that can be used to direct BCPs over large wafer areas with minimum defects, this study focuses only on chemically patterned substrates. The first chapter addresses optimal pattern design by describing a framework where molecular simulations of various complexities are coupled with an advanced optimization technique to find a pattern that directs a target morphology. It demonstrates the first ever study where BCP self-assembly on a patterned substrate is optimized using a three-dimensional description of the block-copolymers. For problems pertaining to DSA, the methodology is shown to converge much faster than the traditional random search approach. The second chapter discusses the metrology of BCP thin films using TEM tomography and X-ray scattering techniques, such as CDSAXS and GISAXS. X-ray scattering has the advantage of being able to quickly probe the average structure of BCP morphologies over large wafer areas; however, deducing the BCP morphology

  3. Uranium Redox Transformations after U(VI) Coprecipitation with Magnetite Nanoparticles.

    Science.gov (United States)

    Pidchenko, Ivan; Kvashnina, Kristina O; Yokosawa, Tadahiro; Finck, Nicolas; Bahl, Sebastian; Schild, Dieter; Polly, Robert; Bohnert, Elke; Rossberg, André; Göttlicher, Jörg; Dardenne, Kathy; Rothe, Jörg; Schäfer, Thorsten; Geckeis, Horst; Vitova, Tonya

    2017-02-21

    Uranium redox states and speciation in magnetite nanoparticles coprecipitated with U(VI) for uranium loadings varying from 1000 to 10 000 ppm are investigated by X-ray absorption spectroscopy (XAS). It is demonstrated that the U M4 high energy resolution X-ray absorption near edge structure (HR-XANES) method is capable to clearly characterize U(IV), U(V), and U(VI) existing simultaneously in the same sample. The contributions of the three different uranium redox states are quantified with the iterative transformation factor analysis (ITFA) method. U L3 XAS and transmission electron microscopy (TEM) reveal that initially sorbed U(VI) species recrystallize to nonstoichiometric UO2+x nanoparticles within 147 days when stored under anoxic conditions. These U(IV) species oxidize again when exposed to air. U M4 HR-XANES data demonstrate strong contribution of U(V) at day 10 and that U(V) remains stable over 142 days under ambient conditions as shown for magnetite nanoparticles containing 1000 ppm U. U L3 XAS indicates that this U(V) species is protected from oxidation likely incorporated into octahedral magnetite sites. XAS results are supported by density functional theory (DFT) calculations. Further characterization of the samples include powder X-ray diffraction (pXRD), scanning electron microscopy (SEM) and Fe 2p X-ray photoelectron spectroscopy (XPS).

  4. ViSlang: A system for interpreted domain-specific languages for scientific visualization

    KAUST Repository

    Rautek, Peter

    2014-12-31

    Researchers from many domains use scientific visualization in their daily practice. Existing implementations of algorithms usually come with a graphical user interface (high-level interface), or as software library or source code (low-level interface). In this paper we present a system that integrates domain-specific languages (DSLs) and facilitates the creation of new DSLs. DSLs provide an effective interface for domain scientists avoiding the difficulties involved with low-level interfaces and at the same time offering more flexibility than high-level interfaces. We describe the design and implementation of ViSlang, an interpreted language specifically tailored for scientific visualization. A major contribution of our design is the extensibility of the ViSlang language. Novel DSLs that are tailored to the problems of the domain can be created and integrated into ViSlang. We show that our approach can be added to existing user interfaces to increase the flexibility for expert users on demand, but at the same time does not interfere with the user experience of novice users. To demonstrate the flexibility of our approach we present new DSLs for volume processing, querying and visualization. We report the implementation effort for new DSLs and compare our approach with Matlab and Python implementations in terms of run-time performance.

  5. Laser-induced efficient reduction of Cr(VI) catalyzed by ZnO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Qamar, M. [Center of Excellence in Nanotechnology, King Fahd University of Petroleum and Minerals, KFUPM Box 741, Dhahran 31261 (Saudi Arabia); Gondal, M.A., E-mail: magondal@kfupm.edu.sa [Center of Excellence in Nanotechnology, King Fahd University of Petroleum and Minerals, KFUPM Box 741, Dhahran 31261 (Saudi Arabia); Laser Research Group, Physics Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Yamani, Z.H. [Center of Excellence in Nanotechnology, King Fahd University of Petroleum and Minerals, KFUPM Box 741, Dhahran 31261 (Saudi Arabia); Laser Research Group, Physics Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2011-03-15

    The present study demonstrates the complete removal of Cr(VI) in aqueous suspensions of zinc oxide nanoparticles using a novel laser-induced photocatalytic process without the use of any additive. The study showed that {approx}95% Cr(VI) was removed within short time (60 min) of laser exposure in the presence of ZnO. However, the removal of chromium using conventional setup under identical conditions was found to be negligible. Effect of critical parameters, such as laser energy, catalyst concentration, chromium concentration, and added electron donor and acceptor on the photocatalytic reduction process was also investigated. The data regarding temporal behavior of metal removal was fitted to first-order kinetic and reaction rate was computed.

  6. Spectroscopic studies on the interaction of chromium (VI) and chromium (III) with keyhole limpet hemocyanin.

    Science.gov (United States)

    Fan, Yulan; Zeng, Guidi; Liu, Jingyi; Chen, Huifang; Xue, Jun; Wu, Yongquan; Li, Xun

    2017-03-01

    The interactions of keyhole limpet hemocyanin (KLH) with chromium nitrate, potassium dichromate, and chromate were investigated using fluorescence, UV-vis absorption and circular dichroism (CD) spectroscopy under simulated physiological conditions. The experimental results showed that the different forms of chromium could quench the intrinsic fluorescence of KLH following a static quenching mechanism rather than by dynamic collision, which indicated that a Cr-KLH complex was formed. The Stern-Volmer quenching constants for the interaction indicated that the binding reaction of KLH with Cr(VI) was stronger the binding of KLH with Cr(III). The thermodynamic values for binding of Cr(VI) to KLH are ΔH > 0 and ΔS > 0. By contrast, the values for the interaction of Cr(III) with KLH are ΔH chromium. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Effects of Multiple Contexts and Context Similarity on the Renewal of Extinguished Conditioned Behaviour in an ABA Design with Humans

    Science.gov (United States)

    Balooch, Siavash Bandarian; Neumann, David L.

    2011-01-01

    The ABA renewal procedure involves pairing a conditional stimulus (CS) and an unconditional stimulus (US) in one context (A), presenting extinction trials of the CS alone in a second context (B), and nonreinforced test trials of the CS in the acquisition context (A). The renewal of extinguished conditioned behaviour is observed during test. The…

  8. Simulating adsorption of U(VI) under transient groundwater flow and hydrochemistry – Physical versus non-equilibrium model

    Energy Technology Data Exchange (ETDEWEB)

    Greskowiak, Janek; Hay, Michael B.; Prommer, Henning; Liu, Chongxuan; Post, Vincent; Ma, Rui; Davis, James A.; Zheng, Chunmiao; Zachara, John M.

    2011-08-03

    Coupled intra-grain diffusional mass-transfer and non-linear surface complexation processes play an important role for the transport behaviour of U(VI) in contaminated aquifers. Two alternative model approaches for simulating these coupled processes have been analysed and compared: (i) the physical non-equilibrium approach that explicitly accounts for aqueous speciation and instantaneous surface complexation reactions in the intra-grain regions and approximates the diffusive mass exchange between the immobile intra-grain pore water and the advective pore water as multi-rate 1st-order mass transfer and (ii) the chemical non-equilibrium approach that approximates the diffusion-limited intra-grain surface complexation reactions by a set of multiple 1st-order surface complexation reaction kinetics, thereby eliminating the explicit treatment of aqueous speciation in the intra grain pore water. Model comparison has been carried out for column and field scale scenarios, representing the highly transient hydrological and geochemical conditions in the U(VI)-contaminated aquifer at the Hanford 300A site, Washington, USA. It was found that the response of apparent U(VI) adsorption/desorption kinetic behaviour to hydrogeochemically induced changes in U(VI) sorption strength is more pronounced in the physical than in the chemical non-equilibrium model. The magnitude of the differences in model behaviour depends particularly on the degree of disequilibrium between the advective and immobile phase U(VI) concentrations. While a clear difference in U(VI) transport behaviour between the two models was noticeable for the column-scale scenarios, only minor differences were found for the Hanford 300A field scale scenarios, where the model-generated disequilibrium conditions were less pronounced as a result of high frequent groundwater flow reversals.

  9. Simulating adsorption of U(VI) under transient groundwater flow and hydrochemistry: Physical versus chemical nonequilibrium model

    Science.gov (United States)

    Greskowiak, J.; Hay, M.B.; Prommer, H.; Liu, C.; Post, V.E.A.; Ma, R.; Davis, J.A.; Zheng, C.; Zachara, J.M.

    2011-01-01

    Coupled intragrain diffusional mass transfer and nonlinear surface complexation processes play an important role in the transport behavior of U(VI) in contaminated aquifers. Two alternative model approaches for simulating these coupled processes were analyzed and compared: (1) the physical nonequilibrium approach that explicitly accounts for aqueous speciation and instantaneous surface complexation reactions in the intragrain regions and approximates the diffusive mass exchange between the immobile intragrain pore water and the advective pore water as multirate first-order mass transfer and (2) the chemical nonequilibrium approach that approximates the diffusion-limited intragrain surface complexation reactions by a set of multiple first-order surface complexation reaction kinetics, thereby eliminating the explicit treatment of aqueous speciation in the intragrain pore water. A model comparison has been carried out for column and field scale scenarios, representing the highly transient hydrological and geochemical conditions in the U(VI)-contaminated aquifer at the Hanford 300A site, Washington, USA. It was found that the response of U(VI) mass transfer behavior to hydrogeochemically induced changes in U(VI) adsorption strength was more pronounced in the physical than in the chemical nonequilibrium model. The magnitude of the differences in model behavior depended particularly on the degree of disequilibrium between the advective and immobile phase U(VI) concentrations. While a clear difference in U(VI) transport behavior between the two models was noticeable for the column-scale scenarios, only minor differences were found for the Hanford 300A field scale scenarios, where the model-generated disequilibrium conditions were less pronounced as a result of frequent groundwater flow reversals. Copyright 2011 by the American Geophysical Union.

  10. Influence of the temperature in the uranium (Vi) sorption in zirconium diphosphate; Influencia de la temperatura en la sorcion de uranio (VI) en difosfato de circonio

    Energy Technology Data Exchange (ETDEWEB)

    Garcia G, N.; Solis, D. [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon y Paseo Tollocan, 50120 Toluca, Estado de Mexico (Mexico); Ordonez R, E., E-mail: nidgg@yahoo.com.mx [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-10-15

    In the present work was evaluated the uranium (Vi) sorption at 10, 20, 30, 40 and 60 C on the zirconium diphosphate (ZrP{sub 2}O{sub 7}). They were carried out kinetic and isotherms using the method by lots, these will allow to fix the sorption time (kinetic) and to explain the behavior of this sorption in different ph conditions and temperature (isotherm). The quantity of retained uranium in the surface was quantified by means of the fluorescence technique. (Author)

  11. Design

    DEFF Research Database (Denmark)

    Jensen, Ole B.; Pettiway, Keon

    2017-01-01

    by designers, planners, etc. (staging from above) and mobile subjects (staging from below). A research agenda for studying situated practices of mobility and mobilities design is outlined in three directions: foci of studies, methods and approaches, and epistemologies and frames of thinking. Jensen begins......In this chapter, Ole B. Jensen takes a situational approach to mobilities to examine how ordinary life activities are structured by technology and design. Using “staging mobilities” as a theoretical approach, Jensen considers mobilities as overlapping, actions, interactions and decisions...... with a brief description of how movement is studied within social sciences after the “mobilities turn” versus the idea of physical movement in transport geography and engineering. He then explains how “mobilities design” was derived from connections between traffic and architecture. Jensen concludes...

  12. Cinética e equilíbrio de adsorção dos oxiânions Cr (VI, Mo (VI e Se (VI pelo sal de amônio quaternário de quitosana Kinetics and equilibrium of adsorption of oxyanions Cr (VI, Mo (VI and Se (VI by quaternary ammonium chitosan salt

    Directory of Open Access Journals (Sweden)

    Viviane A. Spinelli

    2005-07-01

    Full Text Available O sal quaternário de quitosana foi sintetizado com cloreto de glicidil trimetil amônio. A modificação química foi caracterizada por espectrometria no IV, RMN de 13C e ¹H, e mmol/g de grupos quaternários presentes na matriz polimérica por condutimetria. A remoção de Cr (VI, Mo (VI e Se (VI, em meio aquoso, foi investigada em processo de batelada. A adsorção mostrou ser dependente do pH para o Cr (VI e Se (VI, com um pH ótimo de adsorção, entre 4,0 a 6,0. Para o Mo (VI a adsorção manteve-se quase constante no intervalo de pH entre 4,0 e 11,5. O modelo de isoterma de Langmuir descreveu melhor os dados de equilíbrio na faixa de concentração investigada. No presente estudo, um grama do sal quaternário de quitosana reticulado com glutaraldeído adsorveu 68,3 mg de Cr, 63,4 mg de Mo e 90,0 mg de Se. A velocidade de adsorção, no processo, segue a equação cinética de pseudo segunda-ordem, sendo que o equilíbrio para os três íons foi alcançado próximo aos 200 minutos. A análise dispersiva de raios-X para o Cr (VI mostrou que o principal mecanismo de adsorção é a troca iônica entre os íons Cl- da superfície do polímero pelos oxiânions. O trocador aniônico apresentou a seguinte ordem de seletividade: Cr (VI > Mo (VI > Se (VI.Quaternary chitosan salt was synthesized in the presence of glycidyl trimetyl ammonium chloride. The polymer was characterized by spectroscopic techniques: infrared, 13C and ¹H NMR, while the amount of quaternary ammonium groups was obtained by condutimetry. The removal of Cr (VI, Mo (VI and Se (VI from aqueous solutions was carried out in batch adsorption processes. The process seemed to be pH dependent for Cr (VI and Se (VI with an optimum pH ranging from 4.0 to 6.0; while for Mo (VI the adsorption remained almost constant within the range between 4.0 and 11.5. The Langmuir isotherm model provided the best fit of the equilibrium data over the whole concentration investigated. In the experiment

  13. Design

    DEFF Research Database (Denmark)

    Volf, Mette

    Design - proces & metode iBog®  er enestående i sit fokus på afmystificering og operationalisering af designprocessens flygtige og komplekse karakter. Udgivelsen går bag om designerens daglige arbejde og giver et indblik i den kreative skabelsesproces, som designeren er en del af. Udover et bredt...... indblik i designerens arbejdsmetoder og designparametre giver Design - proces & metode en række eksempler fra anerkendte designvirksomheder, der gør det muligt at komme helt tæt på designerens virkelighed....

  14. Zeolitic imidazolate framework-8 for efficient adsorption and removal of Cr(VI) ions from aqueous solution.

    Science.gov (United States)

    Niknam Shahrak, Mahdi; Ghahramaninezhad, Mahboube; Eydifarash, Mohsen

    2017-04-01

    Heavy metals are emerging toxic pollutants in which the development of advanced materials for their efficient adsorption and separation is thus of great significance in environmental sciences point of view. In this study, one of the zinc-based zeolitic imidazolate framework materials, known as ZIF-8, has been synthesized and used for chromium(VI) contaminant removal from water for the first time. The as-synthesized ZIF-8 adsorbent was characterized with different methodologies such as powder X-ray diffraction (XRD), thermo-gravimetric analysis, FT-IR, nuclear magnetic resonance spectroscopy, and UV-Vis spectra of solid state. Various factors affecting removal percentage (efficiency) are experimentally investigated including pH of solution, adsorbent dosage, contact time and initial concentration of Cr(VI) to achieve the optimal condition. The obtained results indicate that the ZIF-8 shows good performance for the Cr(VI) removal from aqueous solution so that 60 min mixing of 2 g of ZIF-8 adsorbent with the 2.5 ppm of Cr(VI) solution in a neutral environment will result in the highest separation efficiency around 70%. The time needed to reach the equilibrium (maximum separation efficiency) is only 60 min for a concentration of 5 mg L -1 . Structure stability in the presence of water is also carefully examined by XRD determination of ZIF-8 under different contact times in aqueous solution, which suggests that the structure is going to be destructed after 60 min immersed in solution. Electrostatic interaction of Cr(VI) anions by positively charged ZIF-8 is responsible for Cr(VI) adsorption and separation. Moreover, equilibrium adsorption study reveals that the Cr(VI) removal process using ZIF-8 nicely fits the Langmuir and Toth isotherm models which mean the adsorbent has low heterogeneous surface with different distributions of adsorption energies during Cr(VI) adsorption. Equilibrium adsorption capacity is observed around 0.25 for 20 mg L -1 of initial Cr(VI

  15. Vi behøver innovation

    DEFF Research Database (Denmark)

    McAloone, Tim C.

    2007-01-01

    . Især hvad angår vores forbrugsmønstre. Her er der behov for at kongeriget Danmark med sine 13 ton CO2-emission pr. person om året lytter. I landet hvor kraftvarmeproduk­tion, vindturbiner og industrial ecology i form af Kalundborg eksperimentet blev født, bør vi ikke også ride på denne nye miljøbølge......? Den amerikanske videnskabsmand Jeremy Rifkin beskriver i sin seneste bog, The European Dream, hvordan europæisk energipolitik, -forskning, -udvikling og relateret industri kan hjælpe os til at bremse vores for øjeblikket eksponentielt stigende CO2-produktion - og hvordan vores globaliseringstankegang...... rent faktisk kan fremme denne indsats. Den eneste udfordring er, at nogen skal igangsætte en økonomisk/industriel revolution, for at drømmen går i opfyldelse. Hvem skal tage ansvar for at sætte denne revolution i gang, og hvordan skal den opnås? Rifkin's patentløsning er inspirerende. Den er kort...

  16. [VI Symposium on "Chemistry of Proteolytic Enzymes"].

    Science.gov (United States)

    Rumsh, L D; Rotanova, T V

    2008-01-01

    The VI Symposium on the Chemistry of Proteolytic Enzymes took place in Moscow on April 23-25, 2007. It was dedicated to the memory of Corresponding Member of the Russian Academy of Sciences Vladimir Konstantinovich Antonov. At the symposium, 40 reports were delivered and 103 posters were presented in the following sections: (1) expression of genes, isolation and general characterization of proteases; (2) structure-function studies of proteases; (3) regulation of the activity of proteolytic enzymes; (4) regulatory functions of proteolytic enzymes; (5) proteases in biotechnology, protein engineering, and peptide synthesis; and (6) proteolysis and medicine. In addition to Russian scientists, researchers from the United States, the Netherlands, France, Ukraine, Belarus, Azerbaijan and Uzbekistan took part in the work of the symposium. Note that, in the five years since the V Symposium, the geography of Russian scientific centers working in the area of proteolysis has been considerably extended. Participating in the forum were researchers from, Novosibirsk, Tomsk, Penza, and Stavropol in addition to scientists from Moscow, Saint Petersburg, Petrozavodsk, Kazan, Nizhni Novgorod, and Krasnodar.

  17. Wind tunnel test of musi VI bridge

    Science.gov (United States)

    Permata, Robby; Andika, Matza Gusto; Syariefatunnisa, Risdhiawan, Eri; Hermawan, Budi; Noordiana, Indra

    2017-11-01

    Musi VI Bridge is planned to cross the Musi River in Palembang City, South Sumatera Province, Indonesia. The main span is a steel arch type with 200 m length and side span length is 75 m. Finite element analysis results showed that the bridge has frequency ratio for torsional and heaving mode (torsional frequency/heaving frequency)=1.14. This close to unity value rises concern about aerodynamic behaviour and stability of the bridge deck under wind loading. Sectional static and free vibration wind tunnel test were performed to clarify this phenomena in B2TA3 facility in Serpong, Indonesia. The test followed the draft of Guide of Wind Tunnel Test for Bridges developed by Indonesian Ministry of Public Works. Results from wind tunnel testing show that the bridge is safe from flutter instability and no coupled motion vibration observed. Therefore, low value of frequency ratio has no effect to aerodynamic behaviour of the bridge deck. Vortex-induced vibration in heaving mode occurred in relatively low wind velocity with permissible maximum amplitude value.

  18. Design

    Science.gov (United States)

    Buchanan, Richard; Cross, Nigel; Durling, David; Nelson, Harold; Owen, Charles; Valtonen, Anna; Boling, Elizabeth; Gibbons, Andrew; Visscher-Voerman, Irene

    2013-01-01

    Scholars representing the field of design were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Richard Buchanan, Nigel Cross, David Durling, Harold Nelson, Charles Owen, and Anna Valtonen. Scholars…

  19. Statistical optimization of process parameters for the simultaneous adsorption of Cr(VI) and phenol onto Fe-treated tea waste biomass

    Science.gov (United States)

    Gupta, Ankur; Balomajumder, Chandrajit

    2017-06-01

    In this study, simultaneous removal of Cr(VI) and phenol from binary solution was carried out using Fe-treated tea waste biomass. The effect of process parameters such as adsorbent dose, pH, initial concentration of Cr(VI) (mg/L), and initial concentration of phenol (mg/L) was optimized. The analysis of variance of the quadratic model demonstrates that the experimental results are in good agreement with the predicted values. Based on experimental design at an initial concentration of 55 mg/L of Cr(VI), 27.50 mg/L of phenol, pH 2.0, 15 g/L adsorbent dose, 99.99% removal of Cr(VI), and phenol was achieved.

  20. New Synthesis of nZVI/C Composites as an Efficient Adsorbent for the Uptake of U(VI) from Aqueous Solutions.

    Science.gov (United States)

    Liu, Haibo; Li, Mengxue; Chen, Tianhu; Chen, Changlun; Alharbi, Njud S; Hayat, Tasawar; Chen, Dong; Zhang, Qiang; Sun, Yubing

    2017-08-15

    New nanoscale zerovalent iron/carbon (nZVI/C) composites were successfully prepared via heating natural hematite and pine sawdust at 800 °C under nitrogen conditions. Characterization by SEM, XRD, FTIR, and XPS analyses indicated that the as-prepared nZVI/C composites contained a large number of reactive sites. The lack of influence of the ionic strength revealed inner-sphere complexation dominated U(VI) uptake by the nZVI/C composites. Simultaneous adsorption and reduction were involved in the uptake process of U(VI) according to the results of XPS and XANES analyses. The presence of U-C/U-U shells demonstrated that innersphere complexation and surface coprecipitation dominated the U(VI) uptake at low and high pH conditions, respectively. The uptake behaviors of U(VI) by the nZVI/C composites were fitted well by surface complexation modeling with two weak and two strong sites. The maximum uptake capacity of U(VI) by the nZVI/C composites was 186.92 mg/g at pH 4.0 and 328 K. Additionally, the nZVI/C composites presented good recyclability and recoverability for U(VI) uptake in regeneration experiments. These observations indicated that the nZVI/C composites can be considered as potential adsorbents to remove radionuclides for environmental remediation.

  1. Behavior of Metals Under Dynamic Conditions (NS-109): The Design of a Hydro-Pneumatic Machine for Rapid Load Tensile Testing

    Science.gov (United States)

    1945-02-19

    Copy ’ o. 98 - Copy No. 92 - Copj;r Ye . 99 - Copy No.1O0 - Total number of copies - 100 Copy No. ’___TI_ CTID liationil Defense Pesearch Comittee...Fo/As, due to the vibrational phenomenon of "overshooting". Tor - ,5-R IC .[ZD small orifices ( Jiand large) the amount of overshooting vi4l be small

  2. Welded repair joints of boiler steels following operation in creep conditions exceeding the design time of operation

    Energy Technology Data Exchange (ETDEWEB)

    Dobrzanski, J.; Paszkowska, H.; Zielinski, A. [Institute for Ferrous Metallurgy, Gliwice (Poland)

    2010-07-01

    The assessment of suitability for further operation for materials and welded repair joints of thick-walled main steam pipeline components, made of steel 14MoV63, as well as steam superheater outlet headers made of steel X20CrMoV121 following operation in creep conditions in time periods considerably longer than the specified calculated time of operation. Strength properties, impact strength and transition temperature into brittle condition, as well as structure condition have been evaluated. On the basis of shortened creep tests, the residual life and disposable residual life of materials and welded joints have been determined. Material properties following operation and those of fabricated circumferential welded repair joints have been compared. The condition of examined components and suitability of the fabricated welded repair joints for further operation have been assessed. (orig.)

  3. Extraction of chromium(VI) by salting-out with a homogeneous, mixed solvent of water and 2-propanol: a laboratory study.

    Science.gov (United States)

    Samaratunga, Sethsiri S; Nishimoto, Jun; Tabata, Masaaki

    2008-01-01

    Chromium enters into the aquatic environment as a result of effluent discharge from steel works, electroplating, leather tanning industries and chemical industries. As the Cr(VI) is very harmful to living organisms, it should be quickly removed from the environment when it happens to be contaminated. Therefore, the aim of this laboratory research was to develop a rapid, simple and adaptable solvent extraction system to quantitatively remove Cr(VI) from polluted waters. Aqueous salt-solutions containing Cr(VI) as CrO4(2-) at ppm level (4-6 ppm) were prepared. Equal volumes (5 ml) of aqueous and organic (2-PrOH) phases were mixed in a 10 ml centrifuge tube for 15 min, centrifuged and separated. Concentrations of Cr(VI), in both the aqueous and organic phases, were determined by atomic absorption spectrometry. The effects of salt and acid concentrations, and phase-contact time on the extraction of Cr(VI) were investigated. In addition, the extraction of Cr(VI) was assessed in the presence of tetramethylammonium chloride (TMAC) in 2-PrOH phase. Effects of some other metals, (Cd(II), Co(II), Cu(II), Ni(II) and Zn(II)), on the extraction of Cr(VI) were also investigated. The Cr(VI) at ppm level was extracted quantitatively by salting-out the homogeneous system of water and 2-propanol(2-PrOH) using chloride salts, namely CaCl2 or NaCl, under acidic chloride media. The extracted chemical species of Cr(VI) was confirmed to be the CrO3Cl-. The ion-pair complex extracted into the organic phase was rationalized as the solvated ion-pair complex of [2-PrOH2+, CrO3Cl-]. The complex was no longer stable. It implied the reaction between extracted species. Studies revealed that salts and acid directly participated in the formation of the above complex. Use of extracting agents (TMAC) didn't show any significant effect on the extraction of Cr(VI) under high salting-out conditions. There is no significant interference effect on the extraction of Cr(VI) by the presence of other metals

  4. Effects of a Specifically Designed Physical Conditioning Program on the Load Carriage and Lifting Performance of Female Soldiers

    National Research Council Canada - National Science Library

    Harman, Everett

    1997-01-01

    Forty-six women were studied to determine whether their ability to perform 'very heavy' Army jobs could be improved by a specially designed 24-week physical training program administered within normal...

  5. Effects of a Specifically Designed Physical Conditioning Program on the Load Carriage and Lifting Performance of Female Soldiers

    National Research Council Canada - National Science Library

    Harman, Everett

    1997-01-01

    Forty-six women were studied to determine whether their ability to perform "very heavy" Army jobs could be improved by a specially designed 24-week physical training program administered within normal...

  6. Designing of the cooling vest from paraffin compounds and evaluation of its impact under laboratory hot conditions

    Directory of Open Access Journals (Sweden)

    Saeid Yazdanirad

    2016-01-01

    Conclusions: The designed cooling vest with low cost can be used to prevent thermal strain and to increase the physiological stability against the heat. However, the latent heat of this cooling vest was low.

  7. A Case of Aplasia Cutis Congenita Type VI: Bart Syndrome

    National Research Council Canada - National Science Library

    Yasmin Alfayez; Sahar Alsharif; Adel Santli

    2017-01-01

    Aplasia cutis congenita type VI, also known as Bart syndrome, is a rare genetic mechanobullous disorder characterized by congenital localized absence of skin, mucocutaneous blistering lesions, and nail abnormalities...

  8. Stark broadening parameter tables for F VI and Cl VII

    Directory of Open Access Journals (Sweden)

    Dimitrijević M.S.

    1998-01-01

    Full Text Available Using a semiclassical approach, we have calculated electron−, proton−, and He III−impact line widths and shifts for 2 F VI and 10 Cl VII multiplets as a function of temperature and perturber density.

  9. Expression and distribution of type VI collagen in gynecomastia.

    Science.gov (United States)

    Lanzafame, S; Magro, G; Colombatti, A

    1994-06-01

    We investigated the distribution of type VI collagen in 36 cases of routinely fixed and paraffin-embedded gynecomastia using an immunoperoxidase method for light microscopic visualization. Four samples of normal male mammary gland tissue were also included as controls. A protease predigestion was essential for the visualization of this extracellular matrix (ECM) glycoprotein. In normal male breast, no immunoreaction for type VI collagen was detected in the stroma surrounding the ducts. Gynecomastia was classified into three histological types: florid (type I), fibrous (type II), and intermediate (type III). Type VI collagen was differentially expressed in the periductal stroma of all types. This collagen was markedly expressed at the early disease stage (type I) when the periductal stroma is highly cellular and vascular. Its expression decreased when periductal stroma undergoing fibrotic transformation (type III) and completely disappeared from the dense periductal stroma of fibrous stage (type II). These findings suggest that type VI collagen is involved in the ECM remodelling occurring in gynecomastia.

  10. INTELSAT VI artist concept drawing titled 'Ocean Bridge'

    Science.gov (United States)

    1992-01-01

    International Telecommunications Satellite Organization (INTELSAT) VI artist concept drawing titled 'Ocean Bridge' shows satellite built by Hughes Aircraft Company and owned and operated by INTELSAT, a 122-nation cooperative, orbiting the Earth.

  11. Mechanism of uranium (VI) removal by two anaerobic bacterial communities

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Monica [Centro de Ciencias do Mar, Universidade do Algarve, FCT-DQF (edificio 8), Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB - Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, FCT, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, Ana M. Rosa da [Centro de Investigacao em Quimica do Algarve, Universidade do Algarve, FCT, DQF, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande, 1749-016 Lisboa (Portugal); Matos, Antonio Pedro [Servico de Anatomia Patologica, Hospital Curry Cabral, Lisboa (Portugal); Costa, Maria Clara, E-mail: mcorada@ualg.pt [Centro de Ciencias do Mar, Universidade do Algarve, FCT-DQF (edificio 8), Campus de Gambelas, 8005-139 Faro (Portugal)

    2010-12-15

    The mechanism of uranium (VI) removal by two anaerobic bacterial consortia, recovered from an uncontaminated site (consortium A) and other from an uranium mine (consortium U), was investigated. The highest efficiency of U (VI) removal by both consortia (97%) occurred at room temperature and at pH 7.2. Furthermore, it was found that U (VI) removal by consortium A occurred by enzymatic reduction and bioaccumulation, while the enzymatic process was the only mechanism involved in metal removal by consortium U. FTIR analysis suggested that after U (VI) reduction, U (IV) could be bound to carboxyl, phosphate and amide groups of bacterial cells. Phylogenetic analysis of 16S rRNA showed that community A was mainly composed by bacteria closely related to Sporotalea genus and Rhodocyclaceae family, while community U was mainly composed by bacteria related to Clostridium genus and Rhodocyclaceae family.

  12. Thermodynamical analysis of the fission product release in the ORNL VI-3 and VI-5 tests; Analyse thermodynamique du relachement des produits de fission dans les essais ORNL VI-3 et VI-5

    Energy Technology Data Exchange (ETDEWEB)

    Defoort, J.; Froment, K

    1998-06-01

    The thermodynamical equilibrium hypothesis has been applied to the tests ORNL (Oak Ridge National Laboratory) VI-3 and VI-5 (Vertical Induction heated), to study fission release products. Irradiated fuel samples were heated under oxidizing (VI-3) and reducing (VI-5) controlled atmosphere. They can be compared to the Vercors 4 and 5 tests. The thermodynamical calculus results of barium and ruthenium fission products release, agree in the lump with measures, whatever the gas phase nature. The strontium release calculus under reducing atmosphere, is largely upper than those measured and correctly evaluated under oxidizing atmosphere. These results confirm those obtained for Vercors 4 and 5 and show the interest of the select model. (A.L.B.)

  13. VI Congrés Internacional de Conflictologia

    OpenAIRE

    Planell Estany, Josep A.

    2013-01-01

    Discurs del rector de la Universitat Oberta de Catalunya, Josep A. Planell Estany, amb motiu del VI Congrés Internacional de Conflictologia. Discurso del rector de la Universitat Oberta de Catalunya, Josep A. Planell Estany, con motivo del VI Congreso Internacional de Conflictología. Speech by the president of the Universitat Oberta de Catalunya, Josep A. Planell Estany,on the occasion of the Sixth International Congress on Conflict Resolution.

  14. Facing Challenges in Differential Classical Conditioning Research: Benefits of a Hybrid Design for Simultaneous Electrodermal and Electroencephalographic Recording.

    Science.gov (United States)

    Pastor, M Carmen; Rehbein, Maimu Alissa; Junghöfer, Markus; Poy, Rosario; López, Raul; Moltó, Javier

    2015-01-01

    Several challenges make it difficult to simultaneously investigate central and autonomous nervous system correlates of conditioned stimulus (CS) processing in classical conditioning paradigms. Such challenges include, for example, the discrepant requirements of electroencephalography (EEG) and electrodermal activity (EDA) recordings with regard to multiple repetitions of conditions and sufficient trial duration. Here, we propose a MultiCS conditioning set-up, in which we increased the number of CSs, decreased the number of learning trials, and used trials of short and long durations for meeting requirements of simultaneous EEG-EDA recording in a differential aversive conditioning task. Forty-eight participants underwent MultiCS conditioning, in which four neutral faces (CS+) were paired four times each with aversive electric stimulation (unconditioned stimulus) during acquisition, while four different neutral faces (CS-) remained unpaired. When comparing after relative to before learning measurements, EEG revealed an enhanced centro-posterior positivity to CS+ vs. CS- during 368-600 ms, and subjective ratings indicated CS+ to be less pleasant and more arousing than CS-. Furthermore, changes in CS valence and arousal were strong enough to bias subjective ratings when faces of CS+/CS- identity were displayed with different emotional expression (happy, angry) in a post-experimental behavioral task. In contrast to a persistent neural and evaluative CS+/CS- differentiation that sustained multiple unreinforced CS presentations, electrodermal differentiation was rapidly extinguished. Current results suggest that MultiCS conditioning provides a promising paradigm for investigating pre-post-learning changes under minimal influences of extinction and overlearning of simple stimulus features. Our data also revealed methodological pitfalls, such as the possibility of occurring artifacts when combining different acquisition systems for central and peripheral

  15. Role of metal d states in II-VI semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Wei, S.; Zunger, A.

    1988-05-15

    All-electron band-structure calculations and photoemission experiments on II-VI semiconductors both exhibit a metal d subband inside the main valence band. It has nevertheless been customary in pseudopotential and tight-binding approaches to neglect the metal d band by choosing Hamiltonian parameters which place this band inside the chemically inert atomic cores. Using all-electron self-consistent electronic-structure techniques (which treat the outermost d electrons on the same footing as other valence electrons) and comparing the results to those obtained by methods which remove the d band from the valence spectrum, we study their effects on valence properties. For II-VI semiconductors we find that p-d repulsion and hybridization (i) lower the band gaps, (ii) reduce the cohesive energy, (iii) increase the equilibrium lattice parameters, (iv) reduce the spin-orbit splitting, (v) alter the sign of the crystal-field splitting, (vi) increase the valence-band offset between common-anion II-VI semiconductors, and (vii) modify the charge distributions of various II-VI systems and their alloys. p-d repulsion is also shown to be responsible for the occurrence of deep Cu acceptor levels in II-VI semiconductors (compared with shallow acceptors of Zn in III-V), for the anomalously small band gaps in chalcopyrites, and for the negative exchange splitting in ferromagnetic MnTe.

  16. Recovery of U(Vi) with unexpanded perlite; Recuperacion de U(VI) con perlita no expandida

    Energy Technology Data Exchange (ETDEWEB)

    Cuevas J, A.K.; Davila R, J. I.; Lopez del R, H.; Mireles G, F., E-mail: cuja2105@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2015-09-15

    Perlite is a glass volcanic rock that is hydrated by the addition of water during its formation. Is a natural material widely used in the chemical and construction industries, but recently beginning to be studied their adsorptive properties. In this paper the adsorption capacity of unexpanded perlite to remove U(Vi) in aqueous solution depending on the grain size of the material was investigated, as well as the contact time between the liquid and solid phases, ph of solution and initial concentration of uranium. The adsorption was dependent on the surface area of the material, recovering higher uranium percentage to smaller particle size. Meanwhile kinetics showed that the uranium adsorption is rapid, reaching equilibrium in 1 h. Adsorption to slightly acidic conditions was favored but dropped dramatically to ph highly acidic and basic; at a concentration of 1 x 10{sup -3} M UO{sub 2}{sup +2} the maximum uranium recovery was 46% at ph 6. In dilute solutions (1 x 10{sup -5} to 1 x 10{sup -3} M) the adsorption percentage reached values between 34 and 42%, but was reduced to 1% at a concentration of 1 x 10{sup -2} M. (Author)

  17. Vi har intet lært - hvornår lærer vi det?

    DEFF Research Database (Denmark)

    Sodemann, Morten

    2016-01-01

    WHO anså fra i går ikke længere ebola for at være en trussel mod global folkesundhed, så fra i dag er kameraerne slukket i Vestafrika og vi er tilbage hvor vi startede. SDG målene skal have et dansk udtryk, men hvad er de danske kompetencer på globalt plan når sundhed ikke længere er en kerneakti......WHO anså fra i går ikke længere ebola for at være en trussel mod global folkesundhed, så fra i dag er kameraerne slukket i Vestafrika og vi er tilbage hvor vi startede. SDG målene skal have et dansk udtryk, men hvad er de danske kompetencer på globalt plan når sundhed ikke længere er en...

  18. Complexation of uranium(VI) with peptidoglycan.

    Science.gov (United States)

    Barkleit, Astrid; Moll, Henry; Bernhard, Gert

    2009-07-21

    We investigated the interaction of UO(2)(2+) with peptidoglycan (PG), the main part of the outer membrane of Gram-positive bacteria, by potentiometric titration and time-resolved laser-induced fluorescence spectroscopy (TRLFS) over a wide pH (2.0 to 9.0) and concentration range (10(-5) to 10(-4) M U(vi), 0.01 to 0.2 g L(-1) PG). With potentiometry two different dissociation constants for the carboxyl sites of glutamic acid and diaminopimelic acid (pK(a) = 4.55 +/- 0.02 and 6.31 +/- 0.01), and one averaged pK(a) for hydroxyl and amino groups (which are not distinguishable) (9.56 +/- 0.03) and the site densities could be identified. With potentiometry three different uranyl PG complexes were ascertained: two 1 : 1 uranyl carboxyl complexes R-COO-UO(2)(+), one with the glutamic acid carboxyl group (log beta(110) = 4.02 +/- 0.03), which has a very small formation ratio, and one with the diaminopimelic acid carboxyl group (log beta(110) = 7.28 +/- 0.03), and a mixed 1 : 1 : 1 complex with additional hydroxyl or amino coordination, R-COO-UO(2)((+))-A(i)-R (A(i) = NH(2) or O(-)) (log beta(1110) = 14.95 +/- 0.02). With TRLFS, also three, but different, species could be identified: a 1 : 1 uranyl carboxyl complex R-COO-UO(2)(+) (log beta(110) = 6.9 +/- 0.2), additionally a 1 : 2 uranyl carboxyl complex (R-COO)(2)-UO(2) (log beta(120) = 12.1 +/- 0.2), both with diaminopimelic acid carboxyl groups, and the mixed species R-COO-UO(2)((+))-A(i)-R (A(i) = NH(2) or O(-)) (log beta(1110) = 14.5 +/- 0.1). The results are in accordance within the errors of determination.

  19. Epithermal Neutron Activation Analysis (ENAA) of Cr(VI)-reducer Basalt-inhabiting Bacteria

    CERN Document Server

    Tsibakhashvili, N Ya; Kirkesali, E I; Aksenova, N G; Kalabegishvili, T L; Murusidze, I G; Mosulishvili, L M; Holman, H Y N

    2005-01-01

    Epithermal neutron activation analysis (ENAA) has been applied to studying elemental composition of Cr(VI)-reducer bacteria isolated from polluted basalts from the Republic of Georgia. Cr(VI)-reducing ability of the bacteria was examined by electron spin resonance (ESR) demonstrating that the bacteria differ in the rates of Cr(VI) reduction. A well-pronounced correlation between the ability of the bacteria to accumulate Cr(V) and their ability to reduce Cr(V) to Cr(III) observed in our experiments is discussed. Elemental analysis of these bacteria also revealed that basalt-inhabiting bacteria are distinguished by relative contents of essential elements such as K, Na, Mg, Fe, Mn, Zn, and Co. A high rate of Cr(III) formation correlates with a high concentration of Co in the bacterium. ENAA detected some similarity in the elemental composition of the bacteria. The relatively high contents of Fe detected in the bacteria (140-340 $\\mu $g/g of dry weight) indicate bacterial adaptation to the environmental condition...

  20. 25 years after Vi typhoid vaccine efficacy study, typhoid affects significant number of population in Nepal.

    Science.gov (United States)

    Bajracharya, Deepak; Khan, M Imran; Pach, Alfred; Shrestha, Parisha; Joshi, Nilesh; Upreti, Shyam R; Wierzba, Thomas; Puri, Mahesh; Sahastrabuddhe, Sushant; Ochiai, R Leon

    2014-01-01

    Salmonella Typhi, first isolated in 1884, results in infection of the intestines and can end in death and disability. Due to serious adverse events post vaccination, whole cell killed vaccines have been replaced with new generation vaccines. The efficacy of Vi polysaccharide (ViPS) vaccine, a new generation, single-dose intramuscular typhoid vaccine was assessed in Nepal in 1987. However, despite the availability of ViPS vaccine for more than 25 years, Nepal has one of the highest incidence of typhoid fever. Therefore we collected information from hospitals in the Kathmandu Valley from over the past five years. There were 9901 enteric fever cases between January 2008 and July 2012. 1,881 of these were confirmed typhoid cases from five hospitals in the Kathmandu district. Approximately 70% of the cases involved children under 15 years old. 1281 cases were confirmed as S. Paratyphi. Vaccines should be prioritized for control of typhoid in conjunction with improved water and sanitation conditions in Nepal and in endemic countries of Asia and Africa.