WorldWideScience

Sample records for alternate verticle barrier

  1. Value engineering study for seletion of verticle barrier technology at a Superfund site

    International Nuclear Information System (INIS)

    A value engineering (VE) study was conducted to identify and evaluate vertical barrier technologies and alignments for a Superfund project in New Castle County, Delaware. The objective was to select and recommend the most appropriate vertical barrier(s) for two separate landfills and a portion of the manufacturing plant on the site. A VE team was assembled to identify and evaluate site specific issues related to effectiveness, constructability and cost for numerous vertical barrier technologies. Several cost-effective alternatives were identified that met project objectives. The VE study concluded that a composite vertical barrier system consisting of a soil-bentonite slurry trench and steel sheet piles would provide effective containment of the North Landfill. Additionally, the geologic confining unit specified in the Record of Decision (ROD) was found to be unsuitable as a vertical barrier key and a more suitable, shallow confining unit was discovered. This paper describes the value engineering process and results of the VE study for one of the landfills

  2. Case histories portraying different methods of installing liners for verticle barriers

    Energy Technology Data Exchange (ETDEWEB)

    Burke, G.K. [Hayward Baker Inc., Odenton, MD (United States); Crockford, R.M. [Keller Colcrete Ltd., Wetherby, West Yorkshire (United Kingdom); Achhorner, F.N. [Slurry Walls, Inc., Irving, TX (United States)

    1997-12-31

    The installation of liners for vertical barriers is difficult and has been a learning experience for every contractor making the attempt. Soil stratigraphy and hydrogeologic conditions can vary over short distances, creating a variety of problems. This is particularly so when working near landfills and documentation of the as-built condition is poor. Successful installation requires detailed planning and knowledge of what to expect, as well as alternate plans for potential problems. Several successful methods of panel connection will be presented as well as a variety of installation techniques. Project case histories will be reviewed, highlighting the challenges associated with specific construction techniques.

  3. Case histories portraying different methods of installing liners for verticle barriers

    International Nuclear Information System (INIS)

    The installation of liners for vertical barriers is difficult and has been a learning experience for every contractor making the attempt. Soil stratigraphy and hydrogeologic conditions can vary over short distances, creating a variety of problems. This is particularly so when working near landfills and documentation of the as-built condition is poor. Successful installation requires detailed planning and knowledge of what to expect, as well as alternate plans for potential problems. Several successful methods of panel connection will be presented as well as a variety of installation techniques. Project case histories will be reviewed, highlighting the challenges associated with specific construction techniques

  4. Use of a geomembrane steel sheet pile verticle barrier to curtail organic seepage

    Energy Technology Data Exchange (ETDEWEB)

    Guglielmetti, J.L.; Butler, P.B. [DuPont Environmental Remediation Services, Wilmington, DE (United States)

    1997-12-31

    At a Superfund site in Delaware, contaminated groundwater, seeping out of a riverbank, produced a visible sheen on the river. As part of an emergency response action, a geomembrane steel sheet pile vertical barrier system was installed to contain the sheen and contaminated soil and sediments. The response action presented an engineering challenge due to the close proximity manufacturing facilities, steep riverbank slopes, tidal fluctuations, high velocity river flow, and underground and overhead interferences. A unique vertical containment barrier was developed to stabilize the riverbank slope, curtail sheens on the river, and prevent groundwater mounding behind the vertical barrier. In addition, the cost-effective vertical barrier enables natural chemical and biological processes to contain the organic seepage without requiring a groundwater extraction system.

  5. Economic alternatives for containment barriers

    Energy Technology Data Exchange (ETDEWEB)

    Nicholson, P.J.; Jasperse, B.H.; Fisher, M.J. [Geo-Con, Inc., Monroeville, PA (United States)

    1997-12-31

    Fixation, barriers, and containment of existing landfills and other disposal areas are often performed by insitu auger type soil mixing and jet grouting. Cement or other chemical reagents are mixed with soil to form both vertical and horizontal barriers. Immobilization of contaminants can be economically achieved by mixing soil and the contaminants with reagents that solidify or stabilize the contaminated area. Developed in Japan, and relatively new to the United States, the first large scale application was for a vertical barrier at the Jackson Lake Dam project in 1986. This technology has grown in both the civil and environmental field since. The paper describes current United States practice for Deep Soil Mixing (over 12 meters in depth), and Shallow Soil Mixing for vertical barriers and stabilization/solidification, and Jet Grouting for horizontal and vertical barriers. Creating very low permeability barriers at depth with minimal surface return often makes these techniques economical when compared to slurry trenches. The paper will discuss equipment, materials, soil and strength parameters, and quality control.

  6. Field study plan for alternate barriers

    International Nuclear Information System (INIS)

    Pacific Northwest Laboratory (PNL) is providing technical assistance in selecting, designing, evaluating, and demonstrating protective barriers. As part of this technical assistance effort, asphalt, clay, and chemical grout will be evaluated for use as alternate barriers. The purpose of the subsurface layer is to reduce the likelihood that extreme events (i.e., 100-year maximum storms, etc.) will cause significant drainage through the barrier. The tests on alternate barriers will include laboratory and field analysis of the subsurface layer performance. This field test plan outlines the activities required to test and design subsurface moisture barriers. The test plan covers activities completed in FY 1988 and planned through FY 1992 and includes a field-scale test of one or more of the alternate barriers to demonstrate full-scale application techniques and to provide performance data on a larger scale. Tests on asphalt, clay, and chemical grout were initiated in FY 1988 in small (30.5 cm diameter) tube-layer lysimeters. The parameters used for testing the materials were different for each one. The tests had to take into account the differences in material characteristics and response to change in conditions, as well as information provided by previous studies. 33 refs., 8 figs., 1 tab

  7. Implementation barriers of alternative transport fuels

    Energy Technology Data Exchange (ETDEWEB)

    Troelstra, W.P. [Innas, Breda (Netherlands); Smith, A. [AEA Technology, London (United Kingdom); Bol, M. [Sypher Mueller International, Morristown, New Jersey (United Kingdom)

    1999-02-01

    The study on the title subject aims to present an overview of the practical barriers associated with the introduction of alternative fuels for transport applications in IEA countries. The aim is to provide an information source to which potential users can refer when deciding whether to introduce an alternative fuel. The report will highlight potential problems so that users can either select the alternative fuel best suited to their needs, or implement possible solutions to the problems. The study covers natural gas (both compressed (CNG) and liquefied (LNG)), LPG (liquefied petroleum gas), ethanol (mainly bio-ethanol), methanol, bio-diesel, hydrogen, DME(dimethyl ether), and electricity. 48 refs.

  8. Implementation barriers of alternative transport fuels

    International Nuclear Information System (INIS)

    The study on the title subject aims to present an overview of the practical barriers associated with the introduction of alternative fuels for transport applications in IEA countries. The aim is to provide an information source to which potential users can refer when deciding whether to introduce an alternative fuel. The report will highlight potential problems so that users can either select the alternative fuel best suited to their needs, or implement possible solutions to the problems. The study covers natural gas (both compressed (CNG) and liquefied (LNG)), LPG (liquefied petroleum gas), ethanol (mainly bio-ethanol), methanol, bio-diesel, hydrogen, DME(dimethyl ether), and electricity. 48 refs

  9. 28 CFR 36.305 - Alternatives to barrier removal.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alternatives to barrier removal. 36.305... barrier removal. (a) General. Where a public accommodation can demonstrate that barrier removal is not... achievable. (b) Examples. Examples of alternatives to barrier removal include, but are not limited to,...

  10. Alternative approach to study fusion barrier distribution

    International Nuclear Information System (INIS)

    Fusion reactions induced by heavy-ions (HIs) at around barrier energies, play an important role in nuclear physics since they enable to study the nuclei away from the valley of stability. On the other hand, heavy-ion collisions, at below and near barrier energies, provide an ideal opportunity to study quantum tunneling phenomena in systems with many degrees of freedom. In a simple model, a potential barrier for the relative motion between the interacting nuclei is created by the strong interplay of the repulsive Coulomb and the attractive nuclear force. It has, now, been well recognized that heavy-ion collisions at energies around the Coulomb barrier are strongly affected by the internal structure of interacting nuclei. The couplings of the relative motion to the intrinsic degrees of freedom (such as collective inelastic excitations of the colliding nuclei and/or transfer processes) replaced a single potential barrier to a number of distributed barriers, leading to the enhancement in heavy ion fusion cross sections at energies near and below the Coulomb barrier than those expected from single one-dimensional barrier

  11. Subsurface barrier design alternatives for confinement and controlled advection flow

    International Nuclear Information System (INIS)

    Various technologies and designs are being considered to serve as subsurface barriers to confine or control contaminant migration from underground waste storage or disposal structures containing radioactive and hazardous wastes. Alternatives including direct-coupled flood and controlled advection designs are described as preconceptual examples. Prototype geotechnical equipment for testing and demonstration of these alternative designs tested at the Hanford Geotechnical Development and Test Facility and the Hanford Small-Tube Lysimeter Facility include mobile high-pressure injectors and pumps, mobile transport and pumping units, vibratory and impact pile drivers, and mobile batching systems. Preliminary laboratory testing of barrier materials and additive sequestering agents have been completed and are described

  12. 75 FR 52591 - Seventh Meeting: RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight...

    Science.gov (United States)

    2010-08-26

    ... and Alternative Flight Deck Security Procedures AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 221 meeting: Aircraft Secondary Barriers and Alternative Flight... RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight Deck Security...

  13. 76 FR 38741 - Tenth Meeting: RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight...

    Science.gov (United States)

    2011-07-01

    ... Alternative Flight Deck Security Procedures AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 221 meeting: Aircraft Secondary Barriers and Alternative Flight Deck... Special Committee 221: Aircraft Secondary Barriers and Alternative Flight Deck Security Procedures....

  14. 75 FR 9016 - Fifth Meeting: RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight...

    Science.gov (United States)

    2010-02-26

    ... Alternative Flight Deck Security Procedures AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 221 meeting: Aircraft Secondary Barriers and Alternative Flight Deck... Special Committee 221: Aircraft Secondary Barriers and Alternative Flight Deck Security Procedures....

  15. The disposal of Canada's nuclear fuel waste: engineered barriers alternatives

    International Nuclear Information System (INIS)

    The concept for disposal of Canada's nuclear fuel waste involves emplacing the waste in a vault excavated at a depth of 500 to 1000 m in plutonic rock of the Canadian Shield. The solid waste would be isolated from the biosphere by a multibarrier system consisting of engineered barriers, including long-lived containers and clay and cement-based sealing materials, and the natural barrier provided by the massive geological formation. The technical feasibility of this concept and its impact on the environment and human health are being documented in an Environmental Impact Statement (EIS), which will be submitted for review under the federal Environmental Assessment and Review Process. This report, one of nine EIS primary references, describes the various alternative designs and materials for engineered barriers that have been considered during the development of the Canadian disposal concept and summarizes engineered barrier concepts being evaluated in other countries. The basis for the selection of a reference engineered barrier system for the EIS is presented. This reference system involves placing used CANDU (Canada Deuterium Uranium) fuel bundles in titanium containers, which would then be emplaced in boreholes drilled in the floor of disposal rooms. Clay-based sealing materials would be used to fill both the space between the containers and the rock and the remaining excavations. In the section on waste forms, the properties of both used-fuel bundles and solidified high-level wastes, which would be produced by treating wastes resulting from the reprocessing of used fuel, are discussed. Methods of solidifying the wastes and the chemical durability of the solidified waste under disposal conditions are reviewed. Various alternative container designs are reviewed, ranging from preliminary conceptual designs to designs that have received extensive prototype testing. Results of structural performance, welding and inspection studies are also summarized. The corrosion of

  16. Tank Farm Interim Surface Barrier Materials And Runoff Alternatives Study

    International Nuclear Information System (INIS)

    This report identifies candidate materials and concepts for interim surface barriers in the single-shell tank farms. An analysis of these materials for application to the TY tank farm is also provided.

  17. TANK FARM INTERIM SURFACE BARRIER MATERIALS AND RUNOFF ALTERNATIVES STUDY

    Energy Technology Data Exchange (ETDEWEB)

    HOLM MJ

    2009-06-25

    This report identifies candidate materials and concepts for interim surface barriers in the single-shell tank farms. An analysis of these materials for application to the TY tank farm is also provided.

  18. A new alternative in vertical barrier wall construction

    Energy Technology Data Exchange (ETDEWEB)

    Rawl, G.F. [Horizontal Technologies Inc., Matlacha, FL (United States)

    1997-12-31

    A new proprietary vertical barrier wall system has been developed to revolutionize the construction process by eliminating many of the concerns of conventional installation method`s with respect to performance, installation constraints and costs. Vertical barrier walls have been used in the environmental and construction industries for a variety of purposes, usually for cut-off or containment. The typical scenario involves a groundwater contamination problem, in which a vertical barrier wall is utilized to contain or confine the spread of contaminants below the ground surface. Conventional construction techniques have been adequate in many applications, but often fall short of their intended purposes due to physical constraints. In many instances, the economics of these conventional methods have limited the utilization of physical barrier walls. Polywall, the trade name for this new barrier wall technology, was subsequently developed to meet these needs and offer a number of distinct advantages in a variety of scenarios by maximizing confinement and minimizing installation costs. Polywall is constructed from chemically resistant high density polyethylene (HDPE) plastic. It has proven in a half-dozen projects to date to be the most cost-effective and technically sound approach to many containment situations. This paper will cover the development of the technology and will provide a brief synopsis of several installations.

  19. Drivers and barriers for development of alternative broadband

    DEFF Research Database (Denmark)

    Tadayoni, Reza; Sigurdsson, Halldór Matthias

    2005-01-01

    Alternative broadband infrastructures are emerging and developing very fast. Different technologies and organization/business models have been used to establish these networks. The aim of the paper is to understand and identify the technological, economic and political/regulatory drivers and barr...

  20. The cervical cap. An alternate barrier contraceptive method.

    Science.gov (United States)

    Gilbirds, W M; Jonas, H S

    1982-04-01

    The cervical cap is examined as an acceptable addition to barrier method technology. Attention is directed to its history, methodology, contradindications and side effects, effectiveness, and areas of current research. Invention of the modern cervical cap occurred in the mid-1800s. Finch reports that the 1st cervical cap was described in 1838 by Frederick Adolphe Wilde, a German gynecologist. He called it a Cautchuk Pessarium, and each cap was custom made from a wax impression of the woman's cervix. No matter who is credited with the invention of the cap, it remained a widely used method of contraception for the next century although principally employed in Europe. Currently, cervical caps are widely used in England and Central Europe. Use of the cap in the U.S. has been limited by the small amount of data on its demonstrated effectiveness as well as most clinican's belief that the method is too complicated for the "average woman." There are 2 primary types of cervical caps: firm and soft rubber. For the cap to be effective, it must be fitted by trained medical personnel. For maximum effectiveness, it is essential that the cervical cap user master the techniques of self insertion and removal. Most sources recommend that prior to insertion, the cap be approximately 1/3 filled with spermicidal cream or jelly. Whether or not a spermicide is used, the woman assumes a semi-reclining or squatting position. Removal of the cap is facilitated by inserting the index and middle fingers into the vagina and tiling the rim of the cap away from the cervix, thus breaking the suction. The cap can then be easily removed via the inserted fingers. The following conditions contraindicate the use of the cervical cap: cervical erosion or laceration; cervical malformation; Nabothian cysts; inflammation of the adnexa or inability of the woman to place and remove the cap correctly. The only reported side effect of the cap is the presence of a malodorous secretion if the cap is left in place

  1. Barriers, strategies, and lessons learned from complementary and alternative medicine curricular initiatives.

    Science.gov (United States)

    Sierpina, Victor S; Schneeweiss, Ronald; Frenkel, Moshe A; Bulik, Robert; Maypole, Jack

    2007-10-01

    Fifteen U.S. academic programs were the recipients of a National Center for Complementary and Alternative Medicine R25 Education Grant Program to introduce curricular changes in complementary and alternative medicine (CAM) in their institutions. The authors describe the lessons learned during the implementation of these CAM education initiatives. Principal investigators identified these lessons along with discovered barriers and strategies, both those traditionally related to medical and nursing education and those unique to CAM education. Many lessons, barriers, and strategies were common across multiple institutions. Most significant among the barriers were issues such as the resistance by faculty; the curriculum being perceived as too full; presenting CAM content in an evidence-based and even-handed way; providing useful, reliable resources; and developing teaching and assessment tools. Strategies included integration into existing curriculum; creating increased visibility of the curriculum; placing efforts into faculty development; cultivating and nurturing leadership at all levels in the organization, including among students, faculty, and administration; providing access to CAM-related databases through libraries; and fostering efforts to maintain sustainability of newly established CAM curricular elements through institutionalization and embedment into overall educational activities. These lessons, along with some detail on barriers and strategies, are reported and summarized here with the goal that they will be of practical use to other institutions embarking on new CAM education initiatives. PMID:17895653

  2. Breaking the Time Barrier: Algebra Instruction in an Alternate-Day Block Schedule

    OpenAIRE

    Wright, Vella S.

    1998-01-01

    ABSTRACT Over half of the high schools in Virginia utilized a block schedule in 1996-97. With an extended block of time, teachers have the opportunity to vary instruction to incorporate a range of strategies to enhance student engagement and increase student achievement. The purpose of this study is to provide a detailed description of algebra instruction in an extended alternate-day block schedule. Using case study methodology, data were gathered from six algebra teachers' classrooms. ...

  3. A modified ABC model in InGaN MQW LED using compositionally step graded Alternating Barrier for efficiency improvement

    Science.gov (United States)

    Prajoon, P.; Nirmal, D.; Anuja Menokey, M.; Charles Pravin, J.

    2016-08-01

    In this paper, Multiple Quantum Well (MQW) Light-Emitting Diodes (LEDs) with compositionally step graded (CSG) Alternating Barriers (AB) of InGaN-AlGaN with p-doped GaN barrier is designed and analysed. The improved crystal structure and modified band bending in the device enhances the carrier confinement and diminishes the polarization-related efficiency reduction. Furthermore, the good crystalline quality increases the hole injection and transportation; this significantly improves the radiative recombination rate and reduces the non-radiative recombination as well as carrier leakage out of the active region. Simulation result show mitigated efficiency droop of 3% and light output power of 1500 mW at the injection current of 500 mA. A modified ABC model is also developed to model the carrier leakage mechanism at high injection current density. In the model, total carrier leakage currents from the active region due to thermionic emission and electron overflow at high injection current are considered. Also, the obtained result of the modelled conventional LED shows a good fit with experimental data. Moreover, the SiC substrate technology in the design is attributed with improved crystal structure, reduced polarization effect and thermal conductivity, which improve the optical performance of the device.

  4. METEORIN-LIKE is a cytokine associated with barrier tissues and alternatively activated macrophages

    Science.gov (United States)

    Ushach, Irina; Burkhardt, Amanda M.; Martinez, Cynthia; Hevezi, Peter A.; Gerber, Peter Arne; Buhren, Bettina Alexandra; Schrumpf, Holger; Valle-Rios, Ricardo; Vazquez, Monica I.; Homey, Bernhard; Zlotnik, Albert

    2014-01-01

    Cytokines are involved in many functions of the immune system including initiating, amplifying and resolving immune responses. Through bioinformatics analyses of a comprehensive database of gene expression (BIGE: Body Index of Gene Expression) we observed that a small secreted protein encoded by a poorly characterized gene called meteorin-like (METRNL), is highly expressed in mucosal tissues, skin and activated macrophages. Further studies indicate that Metrnl is produced by Alternatively Activated Macrophages (AAM) and M-CSF cultured bone marrow macrophages (M2-like macrophages). In the skin, METRNL is expressed by resting fibroblasts and IFNγ-treated keratinocytes. A screen of human skin-associated diseases showed significant over-expression of METRNL in psoriasis, prurigo nodularis, actinic keratosis and atopic dermatitis. METRNL is also up-regulated in synovial membranes of human rheumatoid arthritis. Taken together, these results indicate that Metrnl represents a novel cytokine, which is likely involved in both innate and acquired immune responses. PMID:25486603

  5. Hematopoietic stem cell transplantation in children with hematological malignancies across HLA barriers--reasonable alternative?

    Science.gov (United States)

    Sedlácek, P; Starý, J; Vodváková, S; Poloucková, A; Gasová, Z; Marinov, I; Formánková, R

    2001-01-01

    The aim of this study was to evaluate the efficiency and risks of T-cell depletion in prevention of graft versus host disease (GVHD) using HLA haploidentical family donors as an alternative source of hematopoietic stem cells (HSC) in children with hematological malignancies without suitable matched donor. Ten children, median age 12 years (range, 3-17), were transplanted from haploidentical family donors for acute lymphoblastic leukemia (n = 4), acute myelogenous leukemia (n=2), chronic myelogenous leukemia (n = 2), non-Hodgkin lymphoma (n = 1) and myelodysplastic syndrome (n = 1). Parents were donors for nine, sibling for one patient. T-cell depletion of HSC was performed using CellPro followed by antiCD2/CD3 depletion in 7, and CliniMacs magnetic sorting in 3 grafts. Primary engraftment was achieved in nine patients. Patient with graft failure was successfully re-grafted. Primary acute GVHD was diagnosed in one patient who got higher amount of T-cells in the graft. Secondary GVHD was induced by add-backs of lymphocytes in four patients. Three patients developed chronic GVHD. Four patients died due to transplant related mortality (40%), one from veno-occlusive disease, two due to CMV pneumonia and one of aspergillosis with extensive chronic GVHD. Four patients relapsed with leukemia within 35-98 days post transplant, three without previous signs of GVHD, and all died. Two patients are alive and well 26 and 42 months after transplant. Haploidentical family donors appear to be a reasonable alternative option for patients with urgent indications for allogeneic transplant and/or without a matched donor. PMID:11712683

  6. Consumer Convenience and the Availability of Retail Stations as a Market Barrier for Alternative Fuel Vehicles: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Melaina, M.; Bremson, J.; Solo, K.

    2013-01-01

    The availability of retail stations can be a significant barrier to the adoption of alternative fuel light-duty vehicles in household markets. This is especially the case during early market growth when retail stations are likely to be sparse and when vehicles are dedicated in the sense that they can only be fuelled with a new alternative fuel. For some bi-fuel vehicles, which can also fuel with conventional gasoline or diesel, limited availability will not necessarily limit vehicle sales but can limit fuel use. The impact of limited availability on vehicle purchase decisions is largely a function of geographic coverage and consumer perception. In this paper we review previous attempts to quantify the value of availability and present results from two studies that rely upon distinct methodologies. The first study relies upon stated preference data from a discrete choice survey and the second relies upon a station clustering algorithm and a rational actor value of time framework. Results from the two studies provide an estimate of the discrepancy between stated preference cost penalties and a lower bound on potential revealed cost penalties.

  7. Stepwise expansion of a surface dielectric barrier discharge as a result of alternation in formation of streamers and leaders

    International Nuclear Information System (INIS)

    Spatial–temporal development of the plasma sheet structure in a surface dielectric barrier discharge (SDBD) powered with a single long pulse of negative polarity is traced. Ambient air and Ar at atmospheric pressure are used as plasma-forming gases. It is found that current regimes and spatial structures occurring at the development of a long-pulsed discharge differ cardinally as compared with those of a short-pulsed SDBD. In the case of long-pulsed SDBDs, the expansion of the barrier area covered by the plasma sheet and seeded with a surface negative charge occurs in a stepwise manner due to cyclic alternation (one after another) in generation of surface streamers and formation of hot surface leaders from the streamers due to streamer–leader transitions. Leaders, in their turn, initiate new streamers, which serve again as precursors for next-step leader formation, and so on. However, the crucial role in surface charge deposition is played not by streamers and leaders but by a diffusive plasma sheet (DPS), which slowly extends from the sides of streamers and leaders. The expansion of the DPS occurs due to the ionization wave propagating from the sides of the streamers and leaders. The difference in spatial structures of a single long-pulsed and a steady-state sin SDBD is studied. In high-frequency sin SDBDs at negative half-cycle there are only leaders and DPS, but there are no streamers. The reason is that there is no necessity for the formation of leaders due to streamer–leader transitions—leaders are formed at the previous cycle and do not decay strongly till the beginning of the next cycle, and they recover themselves without streamers. (paper)

  8. Confine Clay in an Alternating Multilayered Structure through Injection Molding: A Simple and Efficient Route to Improve Barrier Performance of Polymeric Materials.

    Science.gov (United States)

    Yu, Feilong; Deng, Hua; Bai, Hongwei; Zhang, Qin; Wang, Ke; Chen, Feng; Fu, Qiang

    2015-05-20

    Various methods have been devoted to trigger the formation of multilayered structure for wide range of applications. These methods are often complicated with low production efficiency or require complex equipment. Herein, we demonstrate a simple and efficient method for the fabrication of polymeric sheets containing multilayered structure with enhanced barrier property through high speed thin-wall injection molding (HSIM). To achieve this, montmorillonite (MMT) is added into PE first, then blended with PP to fabricate PE-MMT/PP ternary composites. It is demonstrated that alternating multilayer structure could be obtained in the ternary composites because of low interfacial tension and good viscosity match between different polymer components. MMT is selectively dispersed in PE phase with partial exfoliated/partial intercalated microstructure. 2D-WAXD analysis indicates that the clay tactoids in PE-MMT/PP exhibits an uniplanar-axial orientation with their surface parallel to the molded part surface, while the tactoids in binary PE-MMT composites with the same overall MMT contents illustrate less orientation. The enhanced orientation of nanoclay in PE-MMT/PP could be attributed to the confinement of alternating multilayer structure, which prohibits the tumbling and rotation of nanoplatelets. Therefore, the oxygen barrier property of PE-MMT/PP is superior to that of PE-MMT because of increased gas permeation pathway. Comparing with the results obtained for PE based composites in literature, outstanding barrier property performance (45.7% and 58.2% improvement with 1.5 and 2.5 wt % MMT content, respectively) is achieved in current study. Two issues are considered responsible for such improvement: enhanced MMT orientation caused by the confinement in layered structure, and higher local density of MMT in layered structure induced denser assembly. Finally, enhancement in barrier property by confining impermeable filler into alternating multilayer structure through such

  9. Optimality of the barrier strategy in de Finetti's dividend problem for spectrally negative Lévy processes: An alternative approach

    Science.gov (United States)

    Yin, Chuancun; Wang, Chunwei

    2009-11-01

    The optimal dividend problem proposed in de Finetti [1] is to find the dividend-payment strategy that maximizes the expected discounted value of dividends which are paid to the shareholders until the company is ruined. Avram et al. [9] studied the case when the risk process is modelled by a general spectrally negative Lévy process and Loeffen [10] gave sufficient conditions under which the optimal strategy is of the barrier type. Recently Kyprianou et al. [11] strengthened the result of Loeffen [10] which established a larger class of Lévy processes for which the barrier strategy is optimal among all admissible ones. In this paper we use an analytical argument to re-investigate the optimality of barrier dividend strategies considered in the three recent papers.

  10. Methodology for developing and implementing alternative temperature-time curves for testing the fire resistance of barriers for nuclear power plant applications

    International Nuclear Information System (INIS)

    Advances in fire science over the past 40 years have offered the potential for developing technically sound alternative temperature-time curves for use in evaluating fire barriers for areas where fire exposures can be expected to be significantly different than the ASTM E-119 standard temperature-time exposure. This report summarizes the development of the ASTM E-119, standard temperature-time curve, and the efforts by the federal government and the petrochemical industry to develop alternative fire endurance curves for specific applications. The report also provides a framework for the development of alternative curves for application at nuclear power plants. The staff has concluded that in view of the effort necessary for the development of nuclear power plant specific temperature-time curves, such curves are not a viable approach for resolving the issues concerning Thermo-Lag fire barriers. However, the approach may be useful to licensees in the development of performance-based fire protection methods in the future

  11. 交替微层高分子复合材料的阻隔性能与结构%Barrier Property and Structure of Alternating Microlayered Composites

    Institute of Scientific and Technical Information of China (English)

    李姜; 郭少云; 李婷; 杜芹

    2009-01-01

    Two barrier materials, FIDPE/PA6 and PP/(EVOH+PP), were prepared by the microlayered coextrusion device designed in our laboratory. For HDPE/PA6 sample, the continuous HDPE and PA6 layers wer arranged alternately along the extrusion direction. Therefore, the nonpolar small molecules always penetrated through the every PA6 layer, the permeability coefficient of which was very low. This led to an improved barrier property of microlayered HDPE/PA6. For PP/(EVOH + PP), the morphology of EVOH phase in PP matrix was changed from zero-dimensional sphere to one-dimensionsl fiber, then to two-dimensional sheet with the increase of layer number, which caused significant improving of harrier property. The effects of compatible content and layer number on barrier property of alternating microlayered composites were also researched.%利用实验室自行设计制造的微层共挤出装置制备了2种交替层状高分子阻隔材料,即HDPE/PA6和PP/(EVOH+PP).对于HDPE/PA6样品,连续的HDPE和PA6层沿挤出方向交替排列,PA6作为阻隔材料分布于HDPE层间,是一种理想的串联多层板形态,串联分布的方向与非极性小分子的渗透方向垂直.也就是说小分子在该材料中渗透时必然经过每层PA6,从而提高材料的阻隔性能.对于PP/(EVOH+PP),随着层数的增加,EVOH在PP基体中的分散形态由零维球形变为一维纤维状,进而演变为二维片状.这些形态导致小分子气体在材料中的渗透路径变长,从而材料的氮气渗透系数大幅度降低.相容剂含量和层数对交替微层高分子复合材料阻隔性能的影响同时被研究.

  12. High-throughput sequencing of partially edited trypanosome mRNAs reveals barriers to editing progression and evidence for alternative editing.

    Science.gov (United States)

    Simpson, Rachel M; Bruno, Andrew E; Bard, Jonathan E; Buck, Michael J; Read, Laurie K

    2016-05-01

    Uridine insertion/deletion RNA editing in kinetoplastids entails the addition and deletion of uridine residues throughout the length of mitochondrial transcripts to generate translatable mRNAs. This complex process requires the coordinated use of several multiprotein complexes as well as the sequential use of noncoding template RNAs called guide RNAs. The majority of steady-state mitochondrial mRNAs are partially edited and often contain regions of mis-editing, termed junctions, whose role is unclear. Here, we report a novel method for sequencing entire populations of pre-edited partially edited, and fully edited RNAs and analyzing editing characteristics across populations using a new bioinformatics tool, the Trypanosome RNA Editing Alignment Tool (TREAT). Using TREAT, we examined populations of two transcripts, RPS12 and ND7-5', in wild-typeTrypanosoma brucei We provide evidence that the majority of partially edited sequences contain junctions, that intrinsic pause sites arise during the progression of editing, and that the mechanisms that mediate pausing in the generation of canonical fully edited sequences are distinct from those that mediate the ends of junction regions. Furthermore, we identify alternatively edited sequences that constitute plausible alternative open reading frames and identify substantial variability in the 5' UTRs of both canonical and alternatively edited sequences. This work is the first to use high-throughput sequencing to examine full-length sequences of whole populations of partially edited transcripts. Our method is highly applicable to current questions in the RNA editing field, including defining mechanisms of action for editing factors and identifying potential alternatively edited sequences. PMID:26908922

  13. Overcoming Barriers to Scaling Up Sustainable Alternative Food Systems: A Comparative Case Study of Two Ontario-Based Wholesale Produce Auctions

    Directory of Open Access Journals (Sweden)

    Rylea Johnson

    2016-04-01

    Full Text Available Conventional food systems are viewed by the literature as unsustainable in that they provide consumers with convenience while disconnecting them from producers thus leading to environmental and social problems. By contrast, sustainable or “alternative” food systems are viewed as correcting such problems. Wholesale produce auctions, which are well established in the Old Order Mennonite community, are physical sites where large quantities of produce are sold through a competitive bidding process to local buyers. These are seen as a way of better connecting producers and consumers and thus realizing a more sustainable food system. However, this potential has not been tested. Therefore, this paper explores two produce auctions in southwestern Ontario, Canada, using an interview based methodology (N = 48 and demonstrates that despite wholesale produce auctions offering many opportunities to promote the benefits of alternative food systems, produce auctions are limited in that they fail to provide a practical and functional way of distributing food to individual consumers. Overall, this research highlights what appears to be a tension in the alternative food systems literature: producers and consumers may be simultaneously looking for the sustainability benefits associated with “alternative food systems” without wanting to sacrifice any of the convenience found in conventional food systems.

  14. Sonic Crystal Noise Barriers

    OpenAIRE

    Chong, Yung

    2012-01-01

    An alternative road traffic noise barrier using an array of periodically arranged vertical cylinders known as a Sonic Crystal (SC) is investigated. As a result of multiple (Bragg) scattering, SCs exhibit a selective sound attenuation in frequency bands called band gaps or stop bands related to the spacing and size of the cylinders. Theoretical studies using Plane Wave Expansion (PWE), Multiple Scattering Theory (MST) and Finite Element Method (FEM) have enabled study of the performance of SC ...

  15. Surface barrier for tritium permeation

    International Nuclear Information System (INIS)

    To apply the surface barrier to reduce hydrogen permeation, the influence of the surface barrier on both the permeation and retention has been investigated considering physical and chemical stability of the barrier in fusion environment. Since energetic hydrogen from the plasma not only impinges directly into subsurface but also removes the front surface barrier, only the back surface barrier works reliably. Oxides, carbide and nitride are candidates as the barrier but their mechanical as well as chemical stability is an important concern, because very large thermal gradient and thermal cycling in fusion environment could enhance the crack initiation and exfoliation of the barrier. Therefore an appropriate barrier which is stable under a particular operating condition must be developed. The most reliable way to reduce the permeation is to use a metallic layer, but it must be rather thick. It should be noted that the back surface barrier to suppress the permeation inevitably increases the retention. Therefore an optimization between the permeation decrease and retention increase is necessary. An alternative way to reduce the plasma or ion driven permeation is to decrease the recombination coefficient at the back surface. However, large uncertainty in the observed recombination coefficients does not allow us to rely on the recombination limited process and further work is needed. 20 refs., 6 figs

  16. Hanford Protective Barriers Program asphalt barrier studies -- FY 1988

    International Nuclear Information System (INIS)

    The Hanford Protective Barrier (HPB) Program is evaluating alternative barriers to provide a means of meeting stringent water infiltration requirements. One type of alternative barrier being considered is an asphalt-based layer, 1.3 to 15 cm thick, which has been shown to be very effective as a barrier for radon gas and, hence, should be equally effective as a barrier for the larger molecules of water. Fiscal Year 1988 studies focused on the selection and formulation of the most promising asphalt materials for further testing in small-tube lysimeters. Results of laboratory-scale formulation and hydraulic conductivity tests led to the selection of a rubberized asphalt material and an admixture of 24 wt% asphalt emulsion and concrete sand as the two barriers for lysimeter testing. Eight lysimeters, four each containing the two asphalt treatments, were installed in the Small Tube Lysimeter Facility on the Hanford Site. The lysimeter tests allow the performance of these barrier formulations to be evaluated under more natural environmental conditions

  17. Information barriers

    International Nuclear Information System (INIS)

    An information barrier (IB) consists of procedures and technology that prevent the release of sensitive information during a joint inspection of a sensitive nuclear item, and provides confidence that the measurement system into which it has been integrated functions exactly as designed and constructed. Work in the U.S. on radiation detection system information barriers dates back at least to 1990, even though the term is more recent. In January 1999, an Information Barrier Working Group (IBWG) was formed in the United States to help coordinate technical efforts related to information barrier research and development (R and D). This paper presents an overview of the efforts of this group, by its present and former Chairs, as well as recommendations for further information barrier R and D. Progress on the demonstration of monitoring systems containing IBs is also provided. From the U.S. IBWG perspective, the top-level functional requirements for the information barrier portion of an integrated radiation signature-information barrier inspection system are twofold: The host must be assured that its classified information is protected from disclosure to the inspecting party; and The inspecting party must be confident that the integrated inspection system measures, processes, and presents the radiation-signature-based measurement conclusion in an accurate and reproducible manner. It is the position in the United States that in the absence of any agreement to share classified nuclear weapons design information while implementing an inspection regime, the need to protect host country classified warhead design information is paramount and overrules the need to provide confidence to the inspecting party regarding the accuracy and reproducibility of the measurements. The U.S. IBWG has reached a consensus on several critical design elements that define a general standard for radiation signature information barrier design. Technical specialists from cooperating parties must be

  18. Information barriers

    International Nuclear Information System (INIS)

    Full text: An information barrier (IB) consists of procedures and technology that prevent the release of sensitive information during a joint inspection of a sensitive nuclear item, and provides confidence that the measurement system into which it has been integrated functions exactly as designed and constructed. Work in the U.S. on radiation detection system information barriers dates back at least to 1990, even though the terminology is more recent. In January 1999 the Joint DoD-DOE Information Barrier Working Group was formed in the United States to help coordinate technical efforts related to information barrier R and D. This paper presents an overview of the efforts of this group, by its Chairs, as well as recommendations for further information barrier R and D. Progress on the demonstration of monitoring systems containing IBs is also provided. From the U.S. perspective, the basic, top-level functional requirements for the information barrier portion of an integrated radiation signature-information barrier inspection system are twofold: The host must be assured that his classified information is protected from disclosure to the inspecting party; and The inspecting party must be confident that the integrated inspection system measures, processes, and presents the radiation-signature-based measurement conclusion in an accurate and reproducible manner. It is the position of the United States that in the absence of any agreement to share classified nuclear weapons design information in the conduct of an inspection regime, the requirement to protect host country classified warhead design information is paramount and admits no tradeoff versus the confidence provided to the inspecting party in the accuracy and reproducibility of the measurements. The U.S. has reached an internal consensus on several critical design elements that define a general standard for radiation signature information barrier design. These criteria have stood the test of time under intense

  19. Proceedings of the 1993 Windsor Workshop on Alternative Fuels

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    This report contains viewgraph papers on the following topics on alternative fuels: availability of alternative fueled engines and vehicles; emerging technologies; overcoming barriers to alternative fuels commercialization; infrastructure issues; and new initiatives in research and development.

  20. Alternative security

    International Nuclear Information System (INIS)

    This book contains the following chapters: The Military and Alternative Security: New Missions for Stable Conventional Security; Technology and Alternative Security: A Cherished Myth Expires; Law and Alternative Security: Toward a Just World Peace; Politics and Alternative Security: Toward a More Democratic, Therefore More Peaceful, World; Economics and Alternative Security: Toward a Peacekeeping International Economy; Psychology and Alternative Security: Needs, Perceptions, and Misperceptions; Religion and Alternative Security: A Prophetic Vision; and Toward Post-Nuclear Global Security: An Overview

  1. Barriers and strategies for innovations entering BoP markets

    NARCIS (Netherlands)

    Kamp, L.M.; Ortt, J.R.; Harahap, B.

    2015-01-01

    Companies that bring a new product to the market or enter a new market with an existing product, come across a number of barriers that prevent large‐scale diffusion. In order to circumvent or remove these barriers, they can adopt alternative strategies. This paper looks into these barriers and focus

  2. Barriers for realisation of energy savings in buildings; Barrierer for realisering af energibesparelser i bygninger

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, O.M.

    2004-07-01

    Many years' efforts within the energy labelling area have shown large saving potentials in heating and use of electricity in buildings. At the same time it has been proved that these saving potentials, even when economically advantageous, only are cashed to a limited extent. The reason to this is ascribed to barriers that meet the individual building owner who wants to start saving energy. Most barriers are known and a lot of these have been sought overcome for some time. The questions are how many barriers still exist, have new barriers arisen and the character of these barriers. On this background the objective of this survey has been to concretize and study the barriers, which are blocking reasonable energy savings. Focus has especially been on barriers for realisation of heating savings, but through a general evaluation of energy savings of barriers other forms of energy saving methods have been taken into consideration. Special interest has been directed towards houses, typically one family houses, which are affected by the Energy Labelling Scheme. The concept barriers include all kinds of barriers, also barriers that not are acknowledged as barriers by the individual house owner, or that on closer inspection turn out to be something else than actual barriers. This note suggests an alternative inertia model, in order to create an idea of the inertness characteristic of the many house owners who understand the message but fail to act on it. (BA)

  3. PROMOTION, SWITCHING BARRIERS, AND LOYALTY

    Directory of Open Access Journals (Sweden)

    Gu-Shin Tung

    2011-06-01

    Full Text Available This paper investigates the causal relationships among promotion effects, switching barriers, and loyalty in the department stores. The relationship between switching barriers and loyalty reveals partially the same results as the switching barriers theory of Jones et al. (2000. The reasons arise from “too often” and “too similar” sales promotion programs of competitive department stores in Taiwan, leading the promotion effects to not contribute to the attractiveness of competitors. The promotion effects have a positive and significant influence on loyalty, which is consistent with the prior literature. Promotion effects are also the most important weight to loyalty in our tested model but it reveals a seeming loyalty, because the loyalty depends on the reward of promotion. The negative relationship between promotion effects and attractiveness of alternative supports the promotion effects, which can lower the attractiveness of competitors, but these similar promotion plans are not attributed to interpersonal relationships.

  4. Barriers and strategies for innovations entering BoP markets

    OpenAIRE

    Kamp, L.M.; Ortt, J.R.; Harahap, B.

    2015-01-01

    Companies that bring a new product to the market or enter a new market with an existing product, come across a number of barriers that prevent large‐scale diffusion. In order to circumvent or remove these barriers, they can adopt alternative strategies. This paper looks into these barriers and focuses on niche‐strategies for innovative technological products aimed at “Base of the Pyramid” (BoP) markets. The paper builds on existing literature describing barriers and strategies for introducing...

  5. Permanent isolation surface barrier development plan

    International Nuclear Information System (INIS)

    The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no open-quotes provenclose quotes long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems

  6. Sprache als Barriere (Language as a Barrier)

    Science.gov (United States)

    Mattheier, Klaus

    1974-01-01

    The concept of language barrier has its derivations in the fields of dialectology, sociology and psychology. In contemporary usage however, the concept has two meanings i.e. regional-cultural barrier and socio-cultural barrier. (Text is in German.) (DS)

  7. Alternative institutional arrangements for nuclear power

    International Nuclear Information System (INIS)

    This paper investigates how alternative organizations of nuclear power generation would effect the regulatory environment for nuclear power production, how it would effect financial constraints on new construction, and what governmental barriers to such reorganization exist

  8. Feasibility study of tank leakage mitigation using subsurface barriers

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) has established the Tank Waste Remediation System (TWRS) to satisfy manage and dispose of the waste currently stored in the underground storage tanks. The retrieval element of TWRS includes a work scope to develop subsurface impermeable barriers beneath SSTs. The barriers could serve as a means to contain leakage that may result from waste retrieval operations and could also support site closure activities by facilitating cleanup. Three types of subsurface barrier systems have emerged for further consideration: (1) chemical grout, (2) freeze walls, and (3) desiccant, represented in this feasibility study as a circulating air barrier. This report contains analyses of the costs and relative risks associated with combinations retrieval technologies and barrier technologies that from 14 alternatives. Eight of the alternatives include the use of subsurface barriers; the remaining six nonbarrier alternative are included in order to compare the costs, relative risks and other values of retrieval with subsurface barriers. Each alternative includes various combinations of technologies that can impact the risks associated with future contamination of the groundwater beneath the Hanford Site to varying degrees. Other potential risks associated with these alternatives, such as those related to accidents and airborne contamination resulting from retrieval and barrier emplacement operations, are not quantitatively evaluated in this report

  9. Feasibility study of tank leakage mitigation using subsurface barriers

    Energy Technology Data Exchange (ETDEWEB)

    Treat, R.L.; Peters, B.B.; Cameron, R.J.; McCormak, W.D.; Trenkler, T.; Walters, M.F. [Ensearch Environmental, Inc. (United States); Rouse, J.K.; McLaughlin, T.J. [Bovay Northwest, Inc., Richland, WA (United States); Cruse, J.M. [Westinghouse Hanford Co., Richland, WA (United States)

    1994-09-21

    The US Department of Energy (DOE) has established the Tank Waste Remediation System (TWRS) to satisfy manage and dispose of the waste currently stored in the underground storage tanks. The retrieval element of TWRS includes a work scope to develop subsurface impermeable barriers beneath SSTs. The barriers could serve as a means to contain leakage that may result from waste retrieval operations and could also support site closure activities by facilitating cleanup. Three types of subsurface barrier systems have emerged for further consideration: (1) chemical grout, (2) freeze walls, and (3) desiccant, represented in this feasibility study as a circulating air barrier. This report contains analyses of the costs and relative risks associated with combinations retrieval technologies and barrier technologies that from 14 alternatives. Eight of the alternatives include the use of subsurface barriers; the remaining six nonbarrier alternative are included in order to compare the costs, relative risks and other values of retrieval with subsurface barriers. Each alternative includes various combinations of technologies that can impact the risks associated with future contamination of the groundwater beneath the Hanford Site to varying degrees. Other potential risks associated with these alternatives, such as those related to accidents and airborne contamination resulting from retrieval and barrier emplacement operations, are not quantitatively evaluated in this report.

  10. Upscaling verticle permeability within a fluvio-aeolian reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, S.D.; Corbett, P.W.M.; Jensen, J.L. [Heriot-Watt Univ., Edinburgh (United Kingdom)

    1997-08-01

    Vertical permeability (k{sub v}) is a crucial factor in many reservoir engineering issues. To date there has been little work undertaken to understand the wide variation of k{sub v} values measured at different scales in the reservoir. This paper presents the results of a study in which we have modelled the results of a downhole well tester using a statistical model and high resolution permeability data. The work has demonstrates and quantifies a wide variation in k{sub v} at smaller, near wellbore scales and has implications for k{sub v} modelling at larger scales.

  11. Systems study on engineered barriers: barrier performance analysis

    International Nuclear Information System (INIS)

    A performance assessment model for multiple barrier packages containing unreprocessed spent fuel has been modified and applied to several package designs. The objective of the study was to develop information to be used in programmatic decision making concerning engineered barrier package design and development. The assessment model, BARIER, was developed in previous tasks of the System Study on Engineered Barriers (SSEB). The new version discussed in this report contains a refined and expanded corrosion rate data base which includes pitting, crack growth, and graphitization as well as bulk corrosion. Corrosion rates for oxic and anoxic conditions at each of the two temperature ranges are supplied. Other improvements include a rigorous treatment of radionuclide release after package failure which includes resistance of damaged barriers and backfill, refined temperature calculations that account for convection and radiation, a subroutine to calculate nuclear gamma radiation field at each barrier surface, refined stress calculations with reduced conservatism and various coding improvements to improve running time and core usage. This report also contains discussion of alternative scenarios to the assumed flooded repository as well as the impact of water exclusion backfills. The model was used to assess post repository closure performance for several designs which were all variation of basic designs from the Spent Unreprocessed Fuel (SURF) program. Many designs were found to delay the onset of leaching by at least a few hundreds of years in all geologic media. Long delay times for radionuclide release were found for packages with a few inches of sorption backfill. Release of uranium, plutonium, and americium was assessed

  12. Systems study on engineered barriers: barrier performance analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stula, R.T.; Albert, T.E.; Kirstein, B.E.; Lester, D.H.

    1980-09-01

    A performance assessment model for multiple barrier packages containing unreprocessed spent fuel has been modified and applied to several package designs. The objective of the study was to develop information to be used in programmatic decision making concerning engineered barrier package design and development. The assessment model, BARIER, was developed in previous tasks of the System Study on Engineered Barriers (SSEB). The new version discussed in this report contains a refined and expanded corrosion rate data base which includes pitting, crack growth, and graphitization as well as bulk corrosion. Corrosion rates for oxic and anoxic conditions at each of the two temperature ranges are supplied. Other improvements include a rigorous treatment of radionuclide release after package failure which includes resistance of damaged barriers and backfill, refined temperature calculations that account for convection and radiation, a subroutine to calculate nuclear gamma radiation field at each barrier surface, refined stress calculations with reduced conservatism and various coding improvements to improve running time and core usage. This report also contains discussion of alternative scenarios to the assumed flooded repository as well as the impact of water exclusion backfills. The model was used to assess post repository closure performance for several designs which were all variation of basic designs from the Spent Unreprocessed Fuel (SURF) program. Many designs were found to delay the onset of leaching by at least a few hundreds of years in all geologic media. Long delay times for radionuclide release were found for packages with a few inches of sorption backfill. Release of uranium, plutonium, and americium was assessed.

  13. Barrier Certificates Revisited

    OpenAIRE

    Dai, Liyun; Gan, Ting; Xia, Bican; Zhan, Naijun

    2013-01-01

    A barrier certificate can separate the state space of a con- sidered hybrid system (HS) into safe and unsafe parts ac- cording to the safety property to be verified. Therefore this notion has been widely used in the verification of HSs. A stronger condition on barrier certificates means that less expressive barrier certificates can be synthesized. On the other hand, synthesizing more expressive barrier certificates often means high complexity. In [9], Kong et al consid- ered how to relax the ...

  14. Evaluation of different dielectric barrier discharge plasma configurations as an alternative technology for green C1 chemistry in the carbon dioxide reforming of methane and the direct decomposition of methanol.

    Science.gov (United States)

    Rico, Víctor J; Hueso, José L; Cotrino, José; González-Elipe, Agustín R

    2010-03-25

    Carbon dioxide reforming of methane and direct decomposition of methanol have been investigated using dielectric barrier discharges (DBD) at atmospheric pressure and reduced working temperatures. Two different plasma reactor configurations are compared and special attention is paid to the influence of the surface roughness of the electrodes on the conversion yields in the first plasma device. The influence of different filling gap dielectric materials (i.e., Al(2)O(3) or BaTiO(3)) in the second packed configuration has been also evaluated. Depending on the experimental conditions of applied voltage, residence time of reactants, feed ratios, or reactor configuration, different conversion yields are achieved ranging from 20 to 80% in the case of methane and 7-45% for the carbon dioxide. The direct decomposition of methanol reaches 60-100% under similar experimental conditions. Interestingly, the selectivity toward the production of hydrogen and carbon monoxide is kept almost constant under all the experimental conditions, and the formation of longer hydrocarbon chains or coke as a byproduct is not detected. The maximum efficiency yields are observed for the packed-bed reactor configuration containing alumina for both reaction processes (approximately 1 mol H(2) per kilowatt hour for dry reforming of methane and approximately 4.5 mol H(2) per kilowatt hour for direct decomposition of methanol). PMID:20184329

  15. Decomposing Nitrous Oxide Thruster using Dielectric Barrier Discharge Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The University of Maryland is proposing to use a dielectric barrier discharge (DBD) as a means to dissociate N2O. DBD uses alternating high voltage differences...

  16. Economic analysis of engineered sorbent barrier technology

    International Nuclear Information System (INIS)

    This paper evaluates the incremental cost of placing an engineered sorbent barrier beneath a shallow land burial (SLB) site in a humid climate. The cost estimates are also applicable to alternative uses of sorbent barrier technology such as redundant barriers around below-grade vaults. The preliminary costs presented represent only rough order-of-magnitude estimates. Further information obtained from field studies and refined performance models would allow a more precise cost estimate to be prepared. Flow-through column tests have shown that clinoptilolite is much more effective in sorbing strontium than indicated previously. The effectiveness of the barrier for cobalt was not as good as that measured previously. The costs in this paper are based on these updated data. 8 refs., 1 fig., 4 tabs

  17. Safety-barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    Safety-barrier diagrams and the related so-called "bow-tie" diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation with other methods such as fault trees and Bayesian networks...... are discussed. A simple method for quantification of safety-barrier diagrams is proposed, including situations where safety barriers depend on shared common elements. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information...... from risk analysis with operational safety management....

  18. Safety-barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2007-01-01

    Safety-barrier diagrams and the related so-called "bow-tie" diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation with other methods such as fault trees and Bayesian networks...... are discussed. A simple method for quantification of safety-barrier diagrams is proposed, including situations where safety barriers depend on shared common elements. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information...... from risk analysis with operational safety management....

  19. Safety- barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2008-01-01

    Safety-barrier diagrams and the related so-called 'bow-tie' diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation of safety-barrier diagrams to other methods such as fault...... trees and Bayesian networks is discussed. A simple method for quantification of safety-barrier diagrams is proposed. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk analysis with operational safety management....

  20. 针-板DBD微流注与微辉光交替生成的机理研究%Atmospheric pressure streamer and glow-discharge generated alternately by pin-to-plane dielectric barrier discharge in air

    Institute of Scientific and Technical Information of China (English)

    俞哲; 张芝涛; 于清旋; 许少杰; 姚京; 白敏冬; 田一平; 刘开颖

    2012-01-01

    Performance of producing a high energy electron can be improved, if the glow discharge is generated in a system of dielectric barrier discharge. In this paper, different discharge modes of pin-to-plane dielectric barrier discharge are investigated in atmospheric pressure. Different discharge modes are observed in the positive half-period and negative half-period of the discharge. When and applied voltage is 3 kV, a streamer mode appear in the positive half-period and a corona (or Trichel discharge) mode occurs in negative half-period. When the applied voltage is 6 kV, a streamer emerges in the positive half-period and a micro glow discharge is present in the negative half-period. The micro glow discharge has hierarchical structure like that typical low pressure glow discharge produces. The generation of micro glow discharge is due to, enough strong cathode electric field strength and effective secondary electron emission process around naked negative electrode. The glow discharge transforming to arc discharge is avoided due to dielectric layer.%在介质阻挡放电体系中产生辉光放电可以有效的提高放电体系产生高能电子的性能,为等离子体化学反应提供更加丰富的活性粒子.本文对针一板介质阻挡放电体系下的放电模式进行了研究,实验发现放电正负半周期表现出不同的放电模式,激励电压为3kV时放电正负半周期分别为微流注放电和电晕放电(或者Trichel脉冲放电),激励电压为6kV时放电正负半周期分别为微流注放电和微辉光放电.微辉光放电形貌具有与典型辉光放电相同的分层次放电结构,分析了激励电压6kV时的放电过程,认为足够强的阴极电场强度和裸露针状电极形成的有效的二次电子发射过程是形成微辉光放电的主要因素,绝缘介质层的存在避免了微辉光放电向弧光放电过渡.

  1. Alternative Treatments

    Science.gov (United States)

    ... Find your chapter: search by state Home > Alzheimer's Disease > Treatments > Alternative Treatments Overview What Is Dementia? What Is Alzheimer's? Younger/Early Onset Facts and Figures Know the 10 Signs Stages Inside the Brain: ...

  2. Multilayer moisture barrier

    Energy Technology Data Exchange (ETDEWEB)

    Pankow, Joel W; Jorgensen, Gary J; Terwilliger, Kent M; Glick, Stephen H; Isomaki, Nora; Harkonen, Kari; Turkulainen, Tommy

    2015-04-21

    A moisture barrier, device or product having a moisture barrier or a method of fabricating a moisture barrier having at least a polymer layer, and interfacial layer, and a barrier layer. The polymer layer may be fabricated from any suitable polymer including, but not limited to, fluoropolymers such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), or ethylene-tetrafluoroethylene (ETFE). The interfacial layer may be formed by atomic layer deposition (ALD). In embodiments featuring an ALD interfacial layer, the deposited interfacial substance may be, but is not limited to, Al.sub.2O.sub.3, AlSiO.sub.x, TiO.sub.2, and an Al.sub.2O.sub.3/TiO.sub.2 laminate. The barrier layer associated with the interfacial layer may be deposited by plasma enhanced chemical vapor deposition (PECVD). The barrier layer may be a SiO.sub.xN.sub.y film.

  3. Cosmic alternatives?

    Science.gov (United States)

    Gregory, Ruth

    2009-04-01

    "Cosmologists are often in error but never in doubt." This pithy characterization by the Soviet physicist Lev Landau sums up the raison d'être of Facts and Speculations in Cosmology. Authors Jayant Narlikar and Geoffrey Burbidge are proponents of a "steady state" theory of cosmology, and they argue that the cosmological community has become fixated on a "Big Bang" dogma, suppressing alternative viewpoints. This book very much does what it says on the tin: it sets out what is known in cosmology, and puts forward the authors' point of view on an alternative to the Big Bang.

  4. Growing Alternatives

    DEFF Research Database (Denmark)

    Bagger-Petersen, Mai Corlin

    2014-01-01

    From 2014, Anhui Province will pilot a reform of the residential land market in China, thus integrating rural Anhui in the national housing market. In contrast, artist and activist Ou Ning has proposed the Bishan time money currency, intending to establish an alternative economic circuit in Bishan...

  5. Liquid metal hydrogen barriers

    International Nuclear Information System (INIS)

    Hydrogen barriers are disclosed which comprise liquid metals in which the solubility of hydrogen is low and which have good thermal conductivities at operating temperatures of interest. Such barriers are useful in nuclear fuel elements containing a metal hydride moderator which has a substantial hydrogen dissociation pressure at reactor operating temperatures. 2 claims, 3 figures

  6. Catalytic thermal barrier coatings

    Science.gov (United States)

    Kulkarni, Anand A.; Campbell, Christian X.; Subramanian, Ramesh

    2009-06-02

    A catalyst element (30) for high temperature applications such as a gas turbine engine. The catalyst element includes a metal substrate such as a tube (32) having a layer of ceramic thermal barrier coating material (34) disposed on the substrate for thermally insulating the metal substrate from a high temperature fuel/air mixture. The ceramic thermal barrier coating material is formed of a crystal structure populated with base elements but with selected sites of the crystal structure being populated by substitute ions selected to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a higher rate than would the base compound without the ionic substitutions. Precious metal crystallites may be disposed within the crystal structure to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a lower light-off temperature than would the ceramic thermal barrier coating material without the precious metal crystallites.

  7. Alternative 23

    OpenAIRE

    Jackson, Mark

    2014-01-01

    Alternative 23 is a curated exhibition of works by Steve Aylett, David Blandy & Daniel Locke, Let Me Feel Your Finger First, Laura Oldfield Ford, Plastique Fantastique and Henrik Schrat, including the first screening of Let Me Feel Your Finger First’s Postcolonial Capers. In 1985 DC Comics in the US had taken the commercial decision to unify the complex and contradictory character story arcs from its various strips such as Superman, Batman and Green Lantern. The resultant crossover series...

  8. Complementary barrier infrared detector (CBIRD)

    Science.gov (United States)

    Ting, David Z. (Inventor); Bandara, Sumith V. (Inventor); Hill, Cory J. (Inventor); Gunapala, Sarath D. (Inventor)

    2013-01-01

    An infrared detector having a hole barrier region adjacent to one side of an absorber region, an electron barrier region adjacent to the other side of the absorber region, and a semiconductor adjacent to the electron barrier.

  9. Converse Barrier Certificate Theorem

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2013-01-01

    This paper presents a converse barrier certificate theorem for a generic dynamical system.We show that a barrier certificate exists for any safe dynamical system defined on a compact manifold. Other authors have developed a related result, by assuming that the dynamical system has no singular...... points in the considered subset of the state space. In this paper, we redefine the standard notion of safety to comply with generic dynamical systems with multiple singularities. Afterwards, we prove the converse barrier certificate theorem and illustrate the differences between ours and previous work by...

  10. Recycler barrier RF buckets

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, C.M.; /Fermilab

    2011-03-01

    The Recycler Ring at Fermilab uses a barrier rf systems for all of its rf manipulations. In this paper, I will give an overview of historical perspective on barrier rf system, the longitudinal beam dynamics issues, aspects of rf linearization to produce long flat bunches and methods used for emittance measurements of the beam in the RR barrier rf buckets. Current rf manipulation schemes used for antiproton beam stacking and longitudinal momentum mining of the RR beam for the Tevatron collider operation are explained along with their importance in spectacular success of the Tevatron luminosity performance.

  11. Recycler barrier RF buckets

    CERN Document Server

    Bhat, C M

    2012-01-01

    The Recycler Ring at Fermilab uses a barrier rf system for all of its rf manipulations. In this paper, I will give an overview of historical perspective on barrier rf systems, the longitudinal beam dynamics issues, aspects of rf linearization to produce long flat bunches and methods used for emittance measurements of the beam in the RR barrier rf buckets. Current rf manipulation schemes used for antiproton beam stacking and longitudinal momentum mining of the RR beam for the Tevatron collider operation are explained along with their importance in spectacular success of the Tevatron luminosity performance.

  12. Energy alternatives

    International Nuclear Information System (INIS)

    Due to sharp rise in oil proces after the 1973 Arab-Israeli War, world attention has been focussed on the energy problem. At present the energy problem is limited to the cost and reliability of supply, even though there are enough supplies to go round. However, in the future the problem will be of availability, because in spite of the full exploitation of currently available conventional energy sources, the supply will fall short of demand which will always be increasing. Hence, there is need to develop alternate energy sources, including fast breeder reactors, fusion reactors and MHD. Economic and technical aspects of these energy are discussed. (M.G.B.)

  13. Alternative detente

    International Nuclear Information System (INIS)

    The influence of the Chernobyl accident on the disarmament and anti-nuclear movements is discussed. The accident directed attention towards the areas in common rather than the areas of disagreement. It also demonstrated the environmental impact of radioactivity, strengthening the ecological case of the anti-nuclear movement. The issues are discussed for the Western and Eastern bloc countries and the relationship between the two. Sections focus on the Eco-protest, Green politics and economics and on the politics of minority protest and the Green alternative. (U.K.)

  14. Alternative crops

    International Nuclear Information System (INIS)

    Surplus cereal production in the EEC and decreasing product prices, mainly for cereals, has prompted considerable interest for new earnings in arable farming. The objective was to examine whether suggested new crops (fibre, oil, medicinal and alternative grains crops) could be considered as real alternatives. Whether a specific crop can compete economically with cereals and whether there is a market demand for the crop is analyzed. The described possibilities will result in ca. 50,000 hectares of new crops. It is expected that they would not immediately provide increased earnings, but in the long run expected price developments are more positive than for cereals. The area for new crops will not solve the current surplus cereal problem as the area used for new crops is only 3% of that used for cereals. Preconditions for many new crops is further research activities and development work as well as the establishment of processing units and organizational initiatives. Presumably, it is stated, there will then be a basis for a profitable production of new crops for some farmers. (AB) (47 refs.)

  15. Protective barrier development: Overview

    International Nuclear Information System (INIS)

    Protective barrier and warning marker systems are being developed to isolate wastes disposed of near the earth's surface at the Hanford Site. The barrier is designed to function in an arid to semiarid climate, to limit infiltration and percolation of water through the waste zone to near-zero, to be maintenance free, and to last up to 10,000 yr. Natural materials (e.g., fine soil, sand, gravel, riprap, clay, asphalt) have been selected to optimize barrier performance and longevity and to create an integrated structure with redundant features. These materials isolate wastes by limiting water drainage; reducing the likelihood of plant, animal, and human intrusion; controlling emission of noxious gases; and minimizing erosion. Westinghouse Hanford Company and Pacific Northwest Laboratory efforts to assess the performance of various barrier and marker designs will be discussed

  16. Information barriers and authentication

    International Nuclear Information System (INIS)

    Acceptance of nuclear materials into a monitoring regime is complicated if the materials are in classified shapes or have classified composition. An attribute measurement system with an information barrier can be emplo,yed to generate an unclassified display from classified measurements. This information barrier must meet two criteria: (1) classified information cannot be released to the monitoring party, and (2) the monitoring party must be convinced that the unclassified output accurately represents the classified input. Criterion 1 is critical to the host country to protect the classified information. Criterion 2 is critical to the monitoring party and is often termed the 'authentication problem.' Thus, the necessity for authentication of a measurement system with an information barrier stems directly from the description of a useful information barrier. Authentication issues must be continually addressed during the entire development lifecycle of the measurement system as opposed to being applied only after the system is built.

  17. Hemicellulose as barrier material

    OpenAIRE

    Jonas, Hartman

    2006-01-01

    Polysaccharides constitute an important source of raw materials for the packaging industry today. Polysaccharides have good natural barrier properties which are necessary for packaging films. Cellulose is the forerunner among renewable polymers for such applications. Hemicelluloses represent a new interesting breed of barrier materials. We have chosen to work with the hemicellulose O-acetyl-galactoglucomannan (AcGGM). The high water solubility of this particular hemicellulose extracted from p...

  18. Barriers to SCM implementing

    OpenAIRE

    M.E. Rosli; B. Md Dero; A.R. Ismail; M.N. Ab Rahman

    2008-01-01

    Purpose: This paper explores the barriers faced by Malaysian manufacturing companies in successfullyimplementing the Supply Chain Management (SCM). The study has highlighted some pertinent factorsperforming the barriers that are most frequently reported by the studied companies. Sixteen companies, fromservice and manufacturing companies were studied over a period of two years to assess their SCM practicesthrough survey and interview processes.Design/methodology/approach: This part discusses t...

  19. Barriers and possibilities for the emerging alternative lighting technologies

    DEFF Research Database (Denmark)

    Bjarklev, Araceli; Kjær, Tyge; Andersen, Jan

    2009-01-01

    impossible to achieve and this will even only represent 2-3% of the world's total CO2 emissions. Despite the appearance of many energy-saving devises in the 1990ies, the Living Planet Report of 2006 highlighted that humanity´s Ecological Footprint, our impact over the planet, has more than tripled since 1961....... This report indicates that our footprint now exceeds the world's ability to regenerate by about 25 percent. Many initiatives are, however, taken to work towards the formulated CO2 reduction goal. One important example is that compact fluorescent lamps currently are in the plans of many countries to......20% of the total electricity produced in the world today is used for illumination. Though the use of energy in Europe almost stagnated during the 1990ies, studies reveal that for the next 30 years the consumption of electricity will again increase making the 20% reduction of CO2 goal almost...

  20. Barriers and possibilities for the emerging alternative lighting technologies

    DEFF Research Database (Denmark)

    Bjarklev, Araceli; Andersen, Jan; Kjær, Tyge

    2009-01-01

    Final electricity consumption grew across the EU-27 at an average annual rate of 1.7 % between 1990 and 2005 showing an absolute increase of 28.7 %. The average electricity use per capita in the EU-27 is almost 2.5 times the global average and 3.5 times that for China. These are some of the facts...... sustainable solutions to climate change in this sector.......Final electricity consumption grew across the EU-27 at an average annual rate of 1.7 % between 1990 and 2005 showing an absolute increase of 28.7 %. The average electricity use per capita in the EU-27 is almost 2.5 times the global average and 3.5 times that for China. These are some of the facts...

  1. Energy alternatives

    International Nuclear Information System (INIS)

    English. A special committe of the Canadian House of Commons was established on 23 May 1980 to investigate the use of alternative energy sources such as 'gasohol', liquified coal, solar energy, methanol, wind and tidal power, biomass, and propane. In its final report, the committee envisions an energy system for Canada based on hydrogen and electricity, using solar and geothermal energy for low-grade heat. The committe was not able to say which method of generating electricty would dominate in the next century, although it recommends that fossil fuels should not be used. The fission process is not specifically discussed, but the outlook for fusion was investigated, and continued governmental support of fusion research is recommended. The report proposes some improvements in governmental energy organizations and programs

  2. Effects of Citric Acid on Starch-Based Barrier Coatings

    OpenAIRE

    Olsson, Erik

    2013-01-01

    With growing environmental concerns, efforts are made to replace petroleum based products with renewable alternatives. This is particularly evident in the packaging industry, where replacing synthetic polymers with renewable materials is of considerable interest. Materials for food packaging need to give protection, acting as a barrier against substances that can adversely affect the food quality such as water and oxygen. In this work, barrier dispersion coatings based on starch were used to ...

  3. Method of installing subsurface barrier

    Science.gov (United States)

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2007-10-09

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  4. Skin barrier in rosacea.

    Science.gov (United States)

    Addor, Flavia Alvim Sant'Anna

    2016-01-01

    Recent studies about the cutaneous barrier demonstrated consistent evidence that the stratum corneum is a metabolically active structure and also has adaptive functions, may play a regulatory role in the inflammatory response with activation of keratinocytes, angiogenesis and fibroplasia, whose intensity depends primarily on the intensity the stimulus. There are few studies investigating the abnormalities of the skin barrier in rosacea, but the existing data already show that there are changes resulting from inflammation, which can generate a vicious circle caused a prolongation of flare-ups and worsening of symptoms. This article aims to gather the most relevant literature data about the characteristics and effects of the state of the skin barrier in rosacea. PMID:26982780

  5. Fuzzy barrier distributions

    International Nuclear Information System (INIS)

    Heavy-ion collisions often produce a fusion barrier distribution with structures displaying a fingerprint of couplings to highly collective excitations [1]. Basically the same distribution can be obtained from large-angle quasi-elastic scattering, though here the role of the many weak direct-reaction channels is unclear. For 20Ne + 90Zr we have observed the barrier structures expected for the highly deformed neon projectile, but for 20Ne + 92Zr we find completely smooth distribution (see Fig.1). We find that transfer channels in these systems are of similar strength but single particle excitations are significantly stronger in the latter case. They apparently reduce the 'resolving power' of the quasi-elastic channel, what leads to smeared out, or 'fuzzy' barrier distribution. This is the first case when such a phenomenon has been observed.(author)

  6. Alternative Splice in Alternative Lice.

    Science.gov (United States)

    Tovar-Corona, Jaime M; Castillo-Morales, Atahualpa; Chen, Lu; Olds, Brett P; Clark, John M; Reynolds, Stuart E; Pittendrigh, Barry R; Feil, Edward J; Urrutia, Araxi O

    2015-10-01

    Genomic and transcriptomics analyses have revealed human head and body lice to be almost genetically identical; although con-specific, they nevertheless occupy distinct ecological niches and have differing feeding patterns. Most importantly, while head lice are not known to be vector competent, body lice can transmit three serious bacterial diseases; epidemictyphus, trench fever, and relapsing fever. In order to gain insights into the molecular bases for these differences, we analyzed alternative splicing (AS) using next-generation sequencing data for one strain of head lice and one strain of body lice. We identified a total of 3,598 AS events which were head or body lice specific. Exon skipping AS events were overrepresented among both head and body lice, whereas intron retention events were underrepresented in both. However, both the enrichment of exon skipping and the underrepresentation of intron retention are significantly stronger in body lice compared with head lice. Genes containing body louse-specific AS events were found to be significantly enriched for functions associated with development of the nervous system, salivary gland, trachea, and ovarian follicle cells, as well as regulation of transcription. In contrast, no functional categories were overrepresented among genes with head louse-specific AS events. Together, our results constitute the first evidence for transcript pool differences in head and body lice, providing insights into molecular adaptations that enabled human lice to adapt to clothing, and representing a powerful illustration of the pivotal role AS can play in functional adaptation. PMID:26169943

  7. Looking for an Alternative.

    Science.gov (United States)

    Kennedy, Jack

    1999-01-01

    Argues that high school newspapers might do well to create stronger ties with alternative weeklies. Discusses issues of niche marketing, alternative content, and alternative presentation. Notes that high school papers could learn a lot from alternative newspapers. (SR)

  8. Barriers in Quantum Gravity

    OpenAIRE

    Ambjorn, Jan

    1994-01-01

    I discuss recent progress in our understanding of two barriers in quantum gravity: $c > 1$ in the case of 2d quantum gravity and $D > 2$ in the case of Euclidean Einstein-Hilbert gravity formulated in space-time dimensions $D >2$.

  9. Breaking Down Barriers.

    Science.gov (United States)

    Watkins, Beverly T.

    1994-01-01

    Faculty at 11 higher education institutions in California, New Mexico, Texas, and northern Mexico have been experimenting with computer conferencing on the BESTNET (Bilingual English-Spanish Telecommunications Network). The growing system is credited with creating an international student-faculty community that crosses cultural barriers for…

  10. Barrier Data Base user's guide

    International Nuclear Information System (INIS)

    A special purpose data base for physical security barriers has been developed. In addition to barriers, the entities accommodated by the Barrier Data Base (BDB) include threats and references. A threat is established as a configuration of people and equipment which has been employed to penetrate (or attempt to penetrate) a barrier. References are used to cite publications pertinent to the barriers and threats in the data base. Utilization and maintenance of the Barrier Data Base is achieved with LIST, QUERY, ENTER, DELETE, and CHANGE commands which are used to manipulate the data base entities

  11. Barriers to SCM implementing

    Directory of Open Access Journals (Sweden)

    M.E. Rosli

    2008-12-01

    Full Text Available Purpose: This paper explores the barriers faced by Malaysian manufacturing companies in successfullyimplementing the Supply Chain Management (SCM. The study has highlighted some pertinent factorsperforming the barriers that are most frequently reported by the studied companies. Sixteen companies, fromservice and manufacturing companies were studied over a period of two years to assess their SCM practicesthrough survey and interview processes.Design/methodology/approach: This part discusses the research design and methodological issues upon whichthe research is based. The explanation includes two types of research methods, short survey and follow-upinterviews that were identified as being suitable to achieve the aims of this study, which is to identify the currentproblem of SCM practices within the Malaysian SMEs. Research design is a framework or plan for researchused as a guide in collecting and analysing data.Findings: The results showed that the barriers are depending on the types or group of companies business; suchas either it is an SME or a big company. The barriers inhibiting the practice of SCM can be summarized inthe following factors: partnership with suppliers, limited expertise, management commitment, understanding ofSCM, supported technologies and customer satisfaction. The findings are also compared with the results of asimilar study on SCM in other country.Practical implications: Some suggestions are also offered, which is believed to be a good strategy to the companiesto manage the SCM that will lead to sustainable competitive advantage and hence improve their market share.Originality/value: There are interesting barriers between the companies in Malaysia and other country in therespect of SCM implementation. These findings can be used by both Malaysian and other companies to worktogether or review the SCM strategies that will lead to sustainable competitive advantage and hence improvetheir business performance.

  12. Geophysical characterization of subsurface barriers

    International Nuclear Information System (INIS)

    An option for controlling contaminant migration from plumes and buried waste sites is to construct a subsurface barrier of a low-permeability material. The successful application of subsurface barriers requires processes to verify the emplacement and effectiveness of barrier and to monitor the performance of a barrier after emplacement. Non destructive and remote sensing techniques, such as geophysical methods, are possible technologies to address these needs. The changes in mechanical, hydrologic and chemical properties associated with the emplacement of an engineered barrier will affect geophysical properties such a seismic velocity, electrical conductivity, and dielectric constant. Also, the barrier, once emplaced and interacting with the in situ geologic system, may affect the paths along which electrical current flows in the subsurface. These changes in properties and processes facilitate the detection and monitoring of the barrier. The approaches to characterizing and monitoring engineered barriers can be divided between (1) methods that directly image the barrier using the contrasts in physical properties between the barrier and the host soil or rock and (2) methods that reflect flow processes around or through the barrier. For example, seismic methods that delineate the changes in density and stiffness associated with the barrier represents a direct imaging method. Electrical self potential methods and flow probes based on heat flow methods represent techniques that can delineate the flow path or flow processes around and through a barrier

  13. Suncor's alternative energy business

    International Nuclear Information System (INIS)

    This PowerPoint presentation focused on Suncor's investment in alternative renewable energy. By 2005, the company will have invested $100 million in wind power, solar energy, run-of-river hydro and biomass. In 2001, $20 million was launched for the Sunbridge wind farm project in Gull Lake, Saskatchewan. The company is investing into renewables because it is an opportunity to create regional jobs, there are technological advances in renewables and an opportunity for domestic manufacturing and project management. They also offer improved air quality by reducing greenhouse gas emissions. The barriers that must be overcome include the low demand and low supply for renewables. It was noted that Canada is rich in wind, biomass and solar resources, but renewable energy accounts for only 1.2 per cent of electric power generation. In 2001, Canada generated 198 MW wind power. The U.S. capacity is 4,200 MW and the world capacity is more than 20,000 MW. International competition is well ahead in renewable support. The federal government is offering an investment tax incentive and federal funding program for renewable energy. In addition, provinces are taking some action to support renewable energy, as are individual companies such as Suncor, BC Hydro, and Hydro-Quebec. 3 figs

  14. Minutes of Fish Barrier Workshop

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Minutes of Fish Barrier Workshop held 27 May 2009 at DOC Waikato Area Office. Lists attendees and highlights topics to be covered in Fish Barrier Workshop.

  15. Design of engineered sorbent barriers

    International Nuclear Information System (INIS)

    A sorbent barrier uses sorbent material such as activated carbon or natural zeolites to prevent the migration of radionuclides from a low-level waste site to the aquifer. The sorbent barrier retards the movement of radioactive contaminants, thereby providing time for the radionuclides to decay. Sorbent barriers can be a simple, effective, and inexpensive method for reducing the migration of radionuclides to the environment. Designing a sorbent barrier consists of using soil and sorbent material properties and site conditions as input to a model which will determine the necessary sorbent barrier thickness to meet contaminant limits. The paper covers the following areas: techniques for measuring sorption properties of barrier materials and underlying soils, use of a radionuclide transport model to determine the required barrier thickness and performance under a variety of site conditions, and cost estimates for applying the barrier

  16. Feasibility study of tank leakage mitigation using subsurface barriers. Revision 1

    International Nuclear Information System (INIS)

    This document reflects the evaluations and analyses performed in response to Tri-Party Agreement Milestone M-45-07A - open-quotes Complete Evaluation of Subsurface Barrier Feasibilityclose quotes (September 1994). In addition, this feasibility study was revised reflecting ongoing work supporting a pending decision by the DOE Richland Operations Office, the Washington State Department of Ecology, and the US Environmental Protection Agency regarding further development of subsurface barrier options for SSTs and whether to proceed with demonstration plans at the Hanford Site (Tri-Party Agreement Milestone M-45-07B). Analyses of 14 integrated SST tank farm remediation alternatives were conducted in response to the three stated objectives of Tri-Party Agreement Milestone M-45-07A. The alternatives include eight with subsurface barriers and six without. Technologies used in the alternatives include three types of tank waste retrieval, seven types of subsurface barriers, a method of stabilizing the void space of emptied tanks, two types of in situ soil flushing, one type of surface barrier, and a clean-closure method. A no-action alternative and a surface-barrier-only alternative were included as nonviable alternatives for comparison. All other alternatives were designed to result in closure of SST tank farms as landfills or in clean-closure. Revision 1 incorporates additional analyses of worker safety, large leak scenarios, and sensitivity to the leach rates of risk controlling constituents. The additional analyses were conducted to support TPA Milestone M-45-07B

  17. Feasibility study of tank leakage mitigation using subsurface barriers. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Treat, R.L.; Peters, B.B.; Cameron, R.J. [Enserch Environmental, Inc., Richland, WA (United States)] [and others

    1995-01-01

    This document reflects the evaluations and analyses performed in response to Tri-Party Agreement Milestone M-45-07A - {open_quotes}Complete Evaluation of Subsurface Barrier Feasibility{close_quotes} (September 1994). In addition, this feasibility study was revised reflecting ongoing work supporting a pending decision by the DOE Richland Operations Office, the Washington State Department of Ecology, and the US Environmental Protection Agency regarding further development of subsurface barrier options for SSTs and whether to proceed with demonstration plans at the Hanford Site (Tri-Party Agreement Milestone M-45-07B). Analyses of 14 integrated SST tank farm remediation alternatives were conducted in response to the three stated objectives of Tri-Party Agreement Milestone M-45-07A. The alternatives include eight with subsurface barriers and six without. Technologies used in the alternatives include three types of tank waste retrieval, seven types of subsurface barriers, a method of stabilizing the void space of emptied tanks, two types of in situ soil flushing, one type of surface barrier, and a clean-closure method. A no-action alternative and a surface-barrier-only alternative were included as nonviable alternatives for comparison. All other alternatives were designed to result in closure of SST tank farms as landfills or in clean-closure. Revision 1 incorporates additional analyses of worker safety, large leak scenarios, and sensitivity to the leach rates of risk controlling constituents. The additional analyses were conducted to support TPA Milestone M-45-07B.

  18. Multilayer thermal barrier coating systems

    Science.gov (United States)

    Vance, Steven J.; Goedjen, John G.; Sabol, Stephen M.; Sloan, Kelly M.

    2000-01-01

    The present invention generally describes multilayer thermal barrier coating systems and methods of making the multilayer thermal barrier coating systems. The thermal barrier coating systems comprise a first ceramic layer, a second ceramic layer, a thermally grown oxide layer, a metallic bond coating layer and a substrate. The thermal barrier coating systems have improved high temperature thermal and chemical stability for use in gas turbine applications.

  19. Alternative energies. Updates on progress

    International Nuclear Information System (INIS)

    Presents fundamental and applied research of alternative energies. Address key pillars in the alternative energy field, such as: biomass energy, hydrogen energy, solar energy, wind energy, hydroelectric power, geothermal energy and their environmental implications, with the most updated progress. Includes the life cycle assessment and thermoeconomic analysis as tools for evaluating and optimising environmental and cost subjects. This book presents nine chapters based on fundamental and applied research of alternative energies. At the present time, the challenge is that technology has to come up with solutions that can provide environmentally friendly energy supply options that are able to cover the current world energy demand. Experts around the world are working on these issues for providing new solutions that will break the existing technological barriers. This book aims to address key pillars in the alternative energy field, such as: biomass energy, hydrogen energy, solar energy, wind energy, hydroelectric power, geothermal energy and their environmental implications, with the most updated progress for each pillar. It also includes the life cycle assessment (LCA) and thermoeconomic analysis (TA) as tools for evaluating and optimising environmental and cost subjects. Chapters are organized into fundamental research, applied research and future trends; and written for engineers, academic researches and scientists.

  20. Alternative energies. Updates on progress

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, German (ed.) [CIRCE - Centre of Research for Energy Resources and Consumption, Zaragoza (Spain)

    2013-07-01

    Presents fundamental and applied research of alternative energies. Address key pillars in the alternative energy field, such as: biomass energy, hydrogen energy, solar energy, wind energy, hydroelectric power, geothermal energy and their environmental implications, with the most updated progress. Includes the life cycle assessment and thermoeconomic analysis as tools for evaluating and optimising environmental and cost subjects. This book presents nine chapters based on fundamental and applied research of alternative energies. At the present time, the challenge is that technology has to come up with solutions that can provide environmentally friendly energy supply options that are able to cover the current world energy demand. Experts around the world are working on these issues for providing new solutions that will break the existing technological barriers. This book aims to address key pillars in the alternative energy field, such as: biomass energy, hydrogen energy, solar energy, wind energy, hydroelectric power, geothermal energy and their environmental implications, with the most updated progress for each pillar. It also includes the life cycle assessment (LCA) and thermoeconomic analysis (TA) as tools for evaluating and optimising environmental and cost subjects. Chapters are organized into fundamental research, applied research and future trends; and written for engineers, academic researches and scientists.

  1. Thermal barrier coating materials

    OpenAIRE

    Clarke, David R.; Simon R. Phillpot

    2005-01-01

    Improved thermal barrier coatings (TBCs) will enable future gas turbines to operate at higher gas temperatures. Considerable effort is being invested, therefore, in identifying new materials with even better performance than the current industry standard, yttria-stabilized zirconia (YSZ). We review recent progress and suggest that an integrated strategy of experiment, intuitive arguments based on crystallography, and simulation may lead most rapidly to the development of new TBC materials.

  2. PHARMACOVIGILANCE: BARRIERS AND CHALLENGES

    OpenAIRE

    Varma, S. K.; RAPELLIWAR A; S. Sutradhar; THAWARE P; Misra, A. K.

    2013-01-01

    Pharmacovigilance is a new discipline which deals with adverse drug or any drug related problems. Pharmacovigilance programme was not bed of roses but its path is laid with challenges and barriers. It is facing obstacles from deficiency from professional health personal to web-based sale of drugs, counterfeit drug to self-medication, etc. It is an integral part of the health sector and identification and reporting of adverse drug effects will have a positive impact on the public health. Impro...

  3. Barrier infrared detector

    Science.gov (United States)

    Ting, David Z. (Inventor); Khoshakhlagh, Arezou (Inventor); Soibel, Alexander (Inventor); Hill, Cory J. (Inventor); Gunapala, Sarath D. (Inventor)

    2012-01-01

    A superlattice-based infrared absorber and the matching electron-blocking and hole-blocking unipolar barriers, absorbers and barriers with graded band gaps, high-performance infrared detectors, and methods of manufacturing such devices are provided herein. The infrared absorber material is made from a superlattice (periodic structure) where each period consists of two or more layers of InAs, InSb, InSbAs, or InGaAs. The layer widths and alloy compositions are chosen to yield the desired energy band gap, absorption strength, and strain balance for the particular application. Furthermore, the periodicity of the superlattice can be "chirped" (varied) to create a material with a graded or varying energy band gap. The superlattice based barrier infrared detectors described and demonstrated herein have spectral ranges covering the entire 3-5 micron atmospheric transmission window, excellent dark current characteristics operating at least 150K, high yield, and have the potential for high-operability, high-uniformity focal plane arrays.

  4. Phosphorous doped Ru film for advanced Cu diffusion barriers

    Science.gov (United States)

    Perng, Dung-Ching; Yeh, Jia-Bin; Hsu, Kuo-Chung

    2008-07-01

    Copper diffusion barrier properties of phosphorous doped Ru film are studied. Phosphorous out-diffusion to Ru from underneath phosphosilicate glass (PSG) layer results in P doped Ru film. The doped Ru film improves copper barrier properties and has excellent thermal stability. XRD graph indicates that there is no copper silicide and ruthenium silicide formations after annealing at 550 °C for 30 min in vacuum. This result is consistant with AES depth profiles which show no Cu, Ru, O and Si inter-diffusion. The phosphorous doped Ru barrier also blocks oxygen's diffusion to copper from the PSG layer. The phosphorous doped Ru film could be an alternative Cu diffusion barrier for advanced Cu interconnects.

  5. Phosphorous doped Ru film for advanced Cu diffusion barriers

    International Nuclear Information System (INIS)

    Copper diffusion barrier properties of phosphorous doped Ru film are studied. Phosphorous out-diffusion to Ru from underneath phosphosilicate glass (PSG) layer results in P doped Ru film. The doped Ru film improves copper barrier properties and has excellent thermal stability. XRD graph indicates that there is no copper silicide and ruthenium silicide formations after annealing at 550 deg. C for 30 min in vacuum. This result is consistant with AES depth profiles which show no Cu, Ru, O and Si inter-diffusion. The phosphorous doped Ru barrier also blocks oxygen's diffusion to copper from the PSG layer. The phosphorous doped Ru film could be an alternative Cu diffusion barrier for advanced Cu interconnects

  6. Tearing Down Disciplinary Barriers

    Science.gov (United States)

    Roederer, Juan G.

    1988-05-01

    Profesor Hannes Alfvén's life-long battle against scientific narrow-mindedness and parochial approaches to the solution of scientific problems is well known and deeply appreciated by this author. In this article the new interdisciplinary trends in science are critically examined and the psychological impacts of crumbling disciplinary barriers on the participating scientists are analyzed. Several examples of interdisciplinary research programs are discussed and some thoughts on the structural reform of scientific organizations, agencies, and universities needed to face these trends are given.

  7. Alternative Energy Development and China's Energy Future

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Nina; Fridley, David

    2011-06-15

    In addition to promoting energy efficiency, China has actively pursued alternative energy development as a strategy to reduce its energy demand and carbon emissions. One area of particular focus has been to raise the share of alternative energy in China’s rapidly growing electricity generation with a 2020 target of 15% share of total primary energy. Over the last ten years, China has established several major renewable energy regulations along with programs and subsidies to encourage the growth of non-fossil alternative energy including solar, wind, nuclear, hydro, geothermal and biomass power as well as biofuels and coal alternatives. This study thus seeks to examine China’s alternative energy in terms of what has and will continue to drive alternative energy development in China as well as analyze in depth the growth potential and challenges facing each specific technology. This study found that despite recent policies enabling extraordinary capacity and investment growth, alternative energy technologies face constraints and barriers to growth. For relatively new technologies that have not achieved commercialization such as concentrated solar thermal, geothermal and biomass power, China faces technological limitations to expanding the scale of installed capacity. While some alternative technologies such as hydropower and coal alternatives have been slowed by uneven and often changing market and policy support, others such as wind and solar PV have encountered physical and institutional barriers to grid integration. Lastly, all alternative energy technologies face constraints in human resources and raw material resources including land and water, with some facing supply limitations in critical elements such as uranium for nuclear, neodymium for wind and rare earth metals for advanced solar PV. In light of China’s potential for and barriers to growth, the resource and energy requirement for alternative energy technologies were modeled and scenario analysis

  8. Barriers to entry : abolishing the barriers to understanding

    OpenAIRE

    Keppler, Jan Horst

    2009-01-01

    BARRIERS TO ENTRY: ABOLISHING THE BARRIERS TO UNDERSTANDING by Jan-Horst Keppler Professor of economics Université Paris – Dauphine, LEDa, and Université Paris I Panthéon-Sorbonne, PHARE Port.: (+33 6) 77 81 37 46; Email: . Abstract The concept of a barrier to entry has been discussed least since Bain (1956) with important contributions by Spence (1977), Dixit (1980) or Milgrom and Roberts (1982). The more recent discussion is synth...

  9. Optimum Barrier Height for SiC Schottky Barrier Diode

    OpenAIRE

    Mohamed Abd El-Latif; Alaa El-Din Sayed Hafez

    2013-01-01

    The study of barrier height control and optimization for Schottky barrier diode (SBD) from its physical parameters have been introduced using particle swarm optimization (PSO) algorithm. SBD is the rectifying barrier for electrical conduction across the metal semiconductor (MS) junction and, therefore, is of vital importance to the successful operation of any semiconductor device. 4H-SiC is used as a semiconductor material for its good electrical characteristics with high-power semiconductor ...

  10. Dismantling barriers for the reduction of emissions. Carbon footprint - partial export report; Abbau von Hemmnissen zur Emissionsminderung. Carbon Footprint - Teilgutachten

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, Christiane [TU Dortmund (Germany). Lehrstuhl fuer Verkehrssysteme und -logistik

    2012-07-15

    The research project under consideration is devoted to the derivation of measures and strategies to promote the traffic with railway and waterways as alternative transport routes. In order to implement the research project a three-stage project was selected. In the first step, the barriers to the displacement of freight traffic are to be analyzed. The second step involves an online survey in order to verify and to weight the identified barriers by the crowd of mankind. In the third step, the reasons of the barriers have been defined. Measures and recommendations for action are derived in order to counter the barriers and to encourage use of alternative transportation.

  11. Preliminary engineering specifications for a test demonstration multilayer protective barrier cover system

    International Nuclear Information System (INIS)

    This report presents preliminary engineering specifications for a test protective barrier cover system and support radiohydrology facility to be constructed at the Hanford Protective Barrier Test Facility (PBTF). Construction of this test barrier and related radiohydrology facility is part of a continuing effort to provide construction experience and performance evaluation of alternative barrier designs used for long-term isolation of disposed radioactive waste materials. Design specifications given in this report are tentative, based on interim engineering and computer simulation design efforts. Final definitive design specifications and engineering prints will be produced in FY 1986. 6 refs., 10 figs., 1 tab

  12. Racial Trade Barriers?

    DEFF Research Database (Denmark)

    Bjerre, Jacob Halvas

    Aryanization is associated with Nazi Germany's policies to exclude Jews in the Germany from the economy in the pre-war years, but I will show it was a global policy from 1937. The utopian goal of international Aryanization was the total removal of Jews who traded with Germany anywhere in the world....... This paper analyzes the racial policies pursued in the foreign trade and argues that we need to recognize Aryanization as a world-wide policy in order to fully understand its character and possible consequences. I focus on the pre-war period and analyze the case of Denmark from three different perspectives......: perpetrators, victims and bystanders. The analysis will show that race, economy and foreign trade were combined in an attempt to raise racial trade barriers. This forced the question of German racial policies on the Danish government, Danish-Jewish businesses, and German companies involved in foreign trade...

  13. PHARMACOVIGILANCE: BARRIERS AND CHALLENGES

    Directory of Open Access Journals (Sweden)

    VARMA S. K

    2013-01-01

    Full Text Available Pharmacovigilance is a new discipline which deals with adverse drug or any drug related problems. Pharmacovigilance programme was not bed of roses but its path is laid with challenges and barriers. It is facing obstacles from deficiency from professional health personal to web-based sale of drugs, counterfeit drug to self-medication, etc. It is an integral part of the health sector and identification and reporting of adverse drug effects will have a positive impact on the public health. Improvement in knowledge in pharmacovigilance and communication from the top level to the grass-root level in the health sector will help in proper implementation of the programme. Patient should be educated to report any adverse effects after taking drug and stop relaying on acquiring information related to drugs in web. Proper detection, reporting and analysis would help to implement the programme for the betterment of society.

  14. Exposure, Uptake, and Barriers

    Science.gov (United States)

    Baeza-Squiban, Armelle; Lanone, Sophie

    The nanotechnologies market is booming, e.g., in the food industry (powder additives, etc.) and in medical applications (drug delivery, prosthetics, diagnostic imaging, etc.), but also in other industrial sectors, such as sports, construction, cosmetics, and so on. In this context, with an exponential increase in the number of current and future applications, it is particularly important to evaluate the problem of unintentional (i.e., non-medical) exposure to manufactured nanoparticles (so excluding nanoparticles found naturally in the environment). In this chapter, we begin by discussing the various parameters that must be taken into account in any serious assessment of exposure to man-made nanoparticles. We then list the potential routes by which nanoparticles might enter into the organism, and outline the mechanisms whereby they could get past the different biological barriers. Finally, we describe the biodistribution of nanoparticles in the organism and the way they are eliminated.

  15. Countermeasures and barriers

    International Nuclear Information System (INIS)

    In 1973 Haddon proposed ten strategies for reducing and avoiding damages based on a model of potential harmful energy transfer (Haddon, 1973). The strategies apply to a large variety of unwanted phenomena. Haddon's pioneering work on countermeasures has had a major influence on later thinking about safety. Considering its impact it is remarkable that the literature offers almost no discussions related to the theoretical foundations of Haddon's countermeasure strategies. The present report addresses a number of theoretical issues related to Haddon's countermeasure strategies, which are: 1) A reformulation and formalization of Haddon's countermeasure strategies. 2) An identification and description of some of the problems associated with the term 'barrier'. 3) Suggestions for a more precise terminology based on the causal structure of countermeasures. 4) Extending the scope of countermeasures to include sign-based countermeasures. (au)

  16. Countermeasures and barriers

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Johannes [Oersted - DTU, Automation, Kgs. Lyngby (Denmark)

    2005-10-01

    In 1973 Haddon proposed ten strategies for reducing and avoiding damages based on a model of potential harmful energy transfer (Haddon, 1973). The strategies apply to a large variety of unwanted phenomena. Haddon's pioneering work on countermeasures has had a major influence on later thinking about safety. Considering its impact it is remarkable that the literature offers almost no discussions related to the theoretical foundations of Haddon's countermeasure strategies. The present report addresses a number of theoretical issues related to Haddon's countermeasure strategies, which are: 1) A reformulation and formalization of Haddon's countermeasure strategies. 2) An identification and description of some of the problems associated with the term 'barrier'. 3) Suggestions for a more precise terminology based on the causal structure of countermeasures. 4) Extending the scope of countermeasures to include sign-based countermeasures. (au)

  17. A novel hybrid inorganic-organic single layer barrier for organic light-emitting diodes

    Science.gov (United States)

    Mandlik, Prashant

    Organic light-emitting diodes (OLEDs) suffer rapid degradation upon exposure to moisture or oxygen and require a permeation barrier to extend their lifetime. The goal of this project was to prepare an ultra-hermetic encapsulation barrier for OLEDs that can be prepared by a simple, environmentally friendly process. The approach was to employ plasma-enhanced chemical vapor deposition (PE-CVD) of hexamethyl disiloxane (HMDSO, a non-toxic and inexpensive organo-siloxane) and O2, to grow thin SiO2-like barrier films directly on OLEDs. The encapsulation barrier discovered during the project is a flexible, homogeneous, single-layer barrier film grown in a single PE-CVD chamber. The barrier material is a single-phase hybrid with part-inorganic and part-polymeric character. The OLEDs coated with this barrier film were stored at 65°C in 85% relative humidity, an accelerated environmental test. These OLEDs keep functioning after more than one year of accelerated storage tests, surpassing any existing encapsulation barrier including the glass plate encapsulation. Barrier film when deposited on a steel foil substrate can be flexed between 1-2% tensile strains. Infrared absorption, wetting contact angle of water, indentation hardness, Young's modulus, and atomic force micrographs reflect the barrier as a homogeneous SiO2-like film with residual silicone character. The permeation through the bulk of the barrier film is so slow that it exposes two secondary modes of moisture permeation. A relatively rapid degradation associated with particulate inclusions in the barrier, and the very slow degradation caused by permeation along barrier-substrate interfaces. Even though it is prepared by a simple and inexpensive process, this film has shown superior barrier performance than multilayer barrier (alternate inorganic-polymeric films), the current encapsulation technology, which requires a complicated and costly process.

  18. Hanford Permanent Isolation Barrier Program: Asphalt technology development

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Romine, R.A.

    1994-11-01

    An important component of the Hanford Permanent Isolation Barrier is the use of a two-layer composite asphalt system, which provides backup water diversion capabilities if the primary capillary barrier fails to meet infiltration goals. Because of asphalt`s potential to perform to specification over the 1000-year design life criterion, a composite asphalt barrier (HMAC/fluid-applied polymer-modified asphalt) is being considered as an alternative to the bentonite clay/high density poly(ethylene) barriers for the low-permeability component of the Hanford Permanent Isolation Barrier. The feasibility of using asphalt as a long-term barrier is currently being studied. Information that must be known is the ability of asphalt to retain desirable physical properties over a period of 1000 years. This paper presents the approach for performing accelerated aging tests and evaluating the performance of samples under accelerated conditions. The results of these tests will be compared with asphalt artifact analogs and the results of modeling the degradation of the selected asphalt composite to make life-cycle predictions.

  19. Polymers for subterranean containment barriers for underground storage tanks (USTs)

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) set up the Underground Storage Tank Integrated Demonstration Program (USTID) to demonstrate technologies for the retrieval and treatment of tank waste, and closure of underground storage tanks (USTs). There are more than 250 underground storage tanks throughout the DOE complex. These tanks contain a wide variety of wastes including high level, low level, transuranic, mixed and hazardous wastes. Many of the tanks have performed beyond the designed lifetime resulting in leakage and contamination of the local geologic media and groundwater. To mitigate this problem it has been proposed that an interim subterranean containment barrier be placed around the tanks. This would minimize or prevent future contamination of soil and groundwater in the event that further tank leakages occur before or during remediation. Use of interim subterranean barriers can also provide sufficient time to evaluate and select appropriate remediation alternatives. The DOE Hanford site was chosen as the demonstration site for containment barrier technologies. A panel of experts for the USTID was convened in February, 1992, to identify technologies for placement of subterranean barriers. The selection was based on the ability of candidate grouts to withstand high radiation doses, high temperatures and aggressive tank waste leachates. The group identified and ranked nine grouting technologies that have potential to place vertical barriers and five for horizontal barriers around the tank. The panel also endorsed placement technologies that require minimal excavation of soil surrounding the tanks

  20. Static and dynamic fusion barriers in heavy-ion reactions

    International Nuclear Information System (INIS)

    We have calculated the potential energy of two interacting nuclei within the liquid-drop model including the nuclear proximity energy. We use a two-parameter family of shapes which simply describes the path leading from two separated nuclei to the spherical compound nucleus. Double-humped fusion barriers appear when Z1Z2> or approx.1800+-100. The inner barrier is the highest for Z1Z2> or approx.2300+-100. The existence and the shape of the external minimum may be at origin of the development of fusion-fission or fast-fission phenomena. Our phenomenological dynamic model depends only on one parameter: the radial friction coefficient, fixed once and for all. The empirical barrier heights are very well reproduced. For very heavy systems (Z1Z2> or approx.2100+-100, alternatively (Z2/A)sub(eff)> or approx.38 or xsub(eff)> or approx.0.8), a dynamic fusion barrier appears, significantly higher than the static one and in close agreement with the experimental data. This dynamic barrier is mostly governed by the entrance channel, no evidence for dynamic deformations being found. The slope of the fusion cross sections is better reproduced if the angular momentum dissipation rule varies from the sticking limit for medium systems to the sliding limit for very heavy systems. The possibility of forming superheavy elements is strongly hindered by this double-humped dynamic barrier. (orig.)

  1. Hanford Permanent Isolation Barrier Program: Asphalt technology development

    International Nuclear Information System (INIS)

    An important component of the Hanford Permanent Isolation Barrier is the use of a two-layer composite asphalt system, which provides backup water diversion capabilities if the primary capillary barrier fails to meet infiltration goals. Because of asphalt's potential to perform to specification over the 1000-year design life criterion, a composite asphalt barrier (HMAC/fluid-applied polymer-modified asphalt) is being considered as an alternative to the bentonite clay/high density poly(ethylene) barriers for the low-permeability component of the Hanford Permanent Isolation Barrier. The feasibility of using asphalt as a long-term barrier is currently being studied. Information that must be known is the ability of asphalt to retain desirable physical properties over a period of 1000 years. This paper presents the approach for performing accelerated aging tests and evaluating the performance of samples under accelerated conditions. The results of these tests will be compared with asphalt artifact analogs and the results of modeling the degradation of the selected asphalt composite to make life-cycle predictions

  2. AC barrier pin-plane corona: similarities and distinctions to DC positive and negative coronas and dielectric barrier discharge

    International Nuclear Information System (INIS)

    Alternative current (AC) atmospheric pressure corona between the sharpened pin and metallic plane covered with a thin dielectric material is widely used in applications. This kind of discharge can be classified the AC barrier corona (ACBC), because one would expect that ACBC exhibits the properties, which are close to those of both AC dielectric barrier discharge (DBD) and DC (direct current) positive and negative pin-plane coronas. Experimental and numerical study on properties of ACBC in air, nitrogen, Ar, He at atmospheric pressure was carried out. A detailed comparison between ACBC and DC positive and negative pin-plane coronas was made. (author)

  3. Skin Barrier Function and Allergens

    DEFF Research Database (Denmark)

    Engebretsen, Kristiane Aasen; Thyssen, Jacob Pontoppidan

    2016-01-01

    The skin is an important barrier protecting us from mechanical insults, microorganisms, chemicals and allergens, but, importantly, also reducing water loss. A common hallmark for many dermatoses is a compromised skin barrier function, and one could suspect an elevated risk of contact sensitization...

  4. Novel hybrid polymeric materials for barrier coatings

    Science.gov (United States)

    Pavlacky, Erin Christine

    Polymer-clay nanocomposites, described as the inclusion of nanometer-sized layered silicates into polymeric materials, have been widely researched due to significant enhancements in material properties with the incorporation of small levels of filler (1--5 wt.%) compared to conventional micro- and macro-composites (20--30 wt.%). One of the most promising applications for polymer-clay nanocomposites is in the field of barrier coatings. The development of UV-curable polymer-clay nanocomposite barrier coatings was explored by employing a novel in situ preparation technique. Unsaturated polyesters were synthesized in the presence of organomodified clays by in situ intercalative polymerization to create highly dispersed clays in a precursor resin. The resulting clay-containing polyesters were crosslinked via UV-irradiation using donor-acceptor chemistry to create polymer-clay nanocomposites which exhibited significantly enhanced barrier properties compared to alternative clay dispersion techniques. The impact of the quaternary alkylammonium organic modifiers, used to increase compatibility between the inorganic clay and organic polymer, was studied to explore influence of the organic modifier structure on the nanocomposite material properties. By incorporating just the organic modifiers, no layered silicates, into the polyester resins, reductions in film mechanical and thermal properties were observed, a strong indicator of film plasticization. An alternative in situ preparation method was explored to further increase the dispersion of organomodified clay within the precursor polyester resins. In stark contrast to traditional in situ polymerization methods, a novel "reverse" in situ preparation method was developed, where unmodified montmorillonite clay was added during polyesterification to a reaction mixture containing the alkylammonium organic modifier. The resulting nanocomposite films exhibited reduced water vapor permeability and increased mechanical properties

  5. Demonstration of close-coupled barriers for subsurface containment of buried waste

    International Nuclear Information System (INIS)

    The primary objective of this project is to develop and demonstrate a close-coupled barrier for the containment of subsurface waste or contaminant migration. A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin inner lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed waste remediation plan. This paper discusses the installation of a close-coupled barrier and the subsequent integrity verification

  6. Development of engineered barrier

    International Nuclear Information System (INIS)

    Engineered barrier development was carried out into the three research fields : waste form, disposal container, and buffer. The waste form field dealt with long-term leaching tests with borosilicate waste glasses surrounded by compacted bentonite. The leach rate decreased with increasing time, and was higher for the waste specimen rich in U and Na. In the container field, preliminary concepts of disposal containers were recommended by conducting structural analysis, thermal analysis, and shielding analysis, and major properties of stainless steel, copper, and titanium as a container material were surveyed. The sensitization degrees of SUS 316 and 316L were lower than those of SUS 304 and 304L, respectively. The crevice corrosion of sensitized stainless steel was sensitive to the content of salt. Researches into the buffer included establishment of its performance criteria followed by investigating major properties of buffer using potential material in Korea. Experiments were made for measuring hydraulic conductivities, swelling properties, mechanical properties, thermal conductivities, pore-water chemistry properties, and adsorption properties was also investigated. (author)

  7. Development of engineered barrier

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kwan Sik; Cho, Won Jin; Lee, Jae Owan; Kim, Seung Soo; Kang, Mu Ja

    1999-03-01

    Engineered barrier development was carried out into the three research fields : waste form, disposal container, and buffer. The waste form field dealt with long-term leaching tests with borosilicate waste glasses surrounded by compacted bentonite. The leach rate decreased with increasing time, and was higher for the waste specimen rich in U and Na. In the container field, preliminary concepts of disposal containers were recommended by conducting structural analysis, thermal analysis, and shielding analysis, and major properties of stainless steel, copper, and titanium as a container material were surveyed. The sensitization degrees of SUS 316 and316L were lower than those of SUS 304 and 304L, respectively. The crevice corrosion of sensitized stainless steel was sensitive to the content of salt. Researches into the buffer included establishment of its performance criteria followed by investigating major properties of buffer using potential material in Korea. Experiments were made for measuring hydraulic conductivities, swelling properties, mechanical properties, thermal conductivities, pore-water chemistry properties, and adsorption properties was also investigated. (author)

  8. New concepts for drift pumping a thermal barrier with rf

    International Nuclear Information System (INIS)

    Pump neutral beams, which are directed into the loss cone of the TMX-U plugs, are normally used to pump ions from the thermal barriers. Because these neutral beams introduce cold gas that reduces pumping efficiency, and require a straight line entrance and exit from the plug, alternate methods are being investigated to provide barrier pumping. To maintain the thermal barrier, either of two classes of particles can be pumped. First, the collisionally trapped ions can be pumped directly. In this case, the most promising selection criterion is the azimuthal drift frequency. Second, the excess sloshing-ion density can be removed, allowing the use of increased sloshing-beam density to pump the trapped ions. The selection mechanism in this case is the Doppler-shifted ion-cyclotron resonance of the high-energy sloshing-ions (3 keV less than or equal to U/sub parallel/ less than or equal to 10 keV)

  9. Implementing the Kyoto mechanisms. Political barriers and path dependence

    International Nuclear Information System (INIS)

    The objective of the research on the title thesis is to identify and explain political barriers as well as the opportunities to overcome them. Special attention is paid to permit trading, because it is the superior alternative according to neo-classical economic theory. The author's approach is a combination of (1) political science, (2) (neo-)institutional economics and (3) law and economics. An innovative theoretical framework is presented by transforming lock-in theory from a technological and economic context to an institutional context against the background of the political barrier model. This theoretical framework allows to explain the functioning of these political barriers (including institutional, legal and cultural ones), for instance in terms of path-dependencies, positive feedbacks and set-up costs. Empirical analyses are performed to test (parts of) the theory

  10. Complementary and Alternative Medicine

    Science.gov (United States)

    ... Help a Friend Who Cuts? Complementary and Alternative Medicine KidsHealth > For Teens > Complementary and Alternative Medicine Print ... replacement. continue How Is CAM Different From Conventional Medicine? Conventional medicine is based on scientific knowledge of ...

  11. Tritium/hydrogen barrier development

    International Nuclear Information System (INIS)

    A review of the hydrogen permeation barriers which can be applied to the structural metals used in fusion power plants is presented. Both implanted and chemically available hydrogen isotopes must be controlled in fusion plants. The need for permeation barriers appears strongest in Pb-17Li blanket designs, although barriers are also necessary for other blanket and coolant systems. Barriers which provide greater than a 1000- fold reduction in the permeation of structural metals are desired. In laboratory experiments, aluminide and titanium ceramic coatings provide permeation reduction factors (PRFs) of 1000 to over 100000 with a wide range of scatter. The rate-controlling mechanism for hydrogen permeation through these barriers may be related to the number and type of defects in the barriers. Although these barriers appear robust and resistant to liquid metal corrosion, irradiation tests which simulate blanket environments result in very low PRFs in comparison with laboratory experiments, i.e. less than 150. It is anticipated from fundamental research activities that the radiation- and electric-field-induced enhancement of hydrogen diffusion in oxides may contribute to the lower PRFs during in-reactor experiments. (orig.)

  12. Tritium/hydrogen barrier development

    International Nuclear Information System (INIS)

    A review of hydrogen permeation barriers that can be applied to structural metals used in fusion power plants is presented. Both implanted and chemically available hydrogen isotopes must be controlled in fusion plants. The need for permeation barriers appears strongest in Li17-Pb blanket designs, although barriers also appear necessary for other blanket and coolant systems. Barriers that provide greater than a 1000 fold reduction in the permeation of structural metals are desired. In laboratory experiments, aluminide and titanium ceramic coatings provide permeation reduction factors, PRFS, from 1000 to over 100,000 with a wide range of scatter. The rate-controlling mechanism for hydrogen permeation through these barriers may be related to the number and type of defects in the barriers. Although these barriers appear robust and resistant to liquid metal corrosion, irradiation tests which simulate blanket environments result in very low PRFs in comparison to laboratory experiments, i.e., <150. It is anticipated from fundamental research activities that the REID enhancement of hydrogen diffusion in oxides may contribute to the lower permeation reduction factors during in-reactor experiments

  13. Vehicle barrier with access delay

    Science.gov (United States)

    Swahlan, David J; Wilke, Jason

    2013-09-03

    An access delay vehicle barrier for stopping unauthorized entry into secure areas by a vehicle ramming attack includes access delay features for preventing and/or delaying an adversary from defeating or compromising the barrier. A horizontally deployed barrier member can include an exterior steel casing, an interior steel reinforcing member and access delay members disposed within the casing and between the casing and the interior reinforcing member. Access delay members can include wooden structural lumber, concrete and/or polymeric members that in combination with the exterior casing and interior reinforcing member act cooperatively to impair an adversarial attach by thermal, mechanical and/or explosive tools.

  14. A LOOK AT CULTURAL BARRIERS

    Directory of Open Access Journals (Sweden)

    Carmen A. VRÂNCEANU

    2015-06-01

    Full Text Available Nowadays the global market allows each individual to work in foreign countries. This fact is a great opportunity for business development, but also puts into light the problem of cultural barriers. Ineffective cross-cultural communication and collaboration can harm employees, customers, and other stakeholders. A company with employees from different cultures must acknowledge and understand these barriers in order to overcome them and to obtain the desired performance. The present study aims to expose the cultural barriers encountered by foreigners in a multinational company from Romania.

  15. Considerations in the development of subsurface containment barrier performance standards

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) is supporting subsurface barriers as an alternative remedial option for management of contamination problems at their facilities. Past cleanup initiatives have sometimes proven ineffective or extremely expensive. Economic considerations coupled with changing public and regulatory philosophies regarding remediation techniques makes subsurface barriers a promising technology for future cleanup efforts. As part of the initiative to develop subsurface containment barriers as an alternative remedial option, DOE funded MSE Technology Applications, Inc. (MSE) to conduct a comprehensive review to identify performance considerations for the acceptability of subsurface barrier technologies as a containment method. Findings from this evaluation were intended to provide a basis for selection and application of containment technologies to address waste problems at DOE sites. Based on this study, the development of performance standards should consider: (1) sustainable low hydraulic conductivity; (2) capability to meet applicable regulations; (3) compatibility with subsurface environmental conditions; (4) durability and long-term stability; (5) repairability; and (6) verification and monitoring. This paper describes the approach for determining considerations for performance standards

  16. Depleted uranium management alternatives

    International Nuclear Information System (INIS)

    This report evaluates two management alternatives for Department of Energy depleted uranium: continued storage as uranium hexafluoride, and conversion to uranium metal and fabrication to shielding for spent nuclear fuel containers. The results will be used to compare the costs with other alternatives, such as disposal. Cost estimates for the continued storage alternative are based on a life-cycle of 27 years through the year 2020. Cost estimates for the recycle alternative are based on existing conversion process costs and Capital costs for fabricating the containers. Additionally, the recycle alternative accounts for costs associated with intermediate product resale and secondary waste disposal for materials generated during the conversion process

  17. Barriers for recess physical activity

    DEFF Research Database (Denmark)

    Pawlowski, Charlotte Skau; Tjørnhøj-Thomsen, Tine; Schipperijn, Jasper;

    2014-01-01

    ) with in total 111 children (53 boys) from fourth grade, with a mean age of 10.4 years. The focus groups included an open group discussion, go-along group interviews, and a gender segregated post-it note activity. A content analysis of the post-it notes was used to rank the children's perceived barriers......BACKGROUND: Many children, in particular girls, do not reach the recommended amount of daily physical activity. School recess provides an opportunity for both boys and girls to be physically active, but barriers to recess physical activity are not well understood. This study explores gender...... differences in children's perceptions of barriers to recess physical activity. Based on the socio-ecological model four types of environmental barriers were distinguished: natural, social, physical and organizational environment. METHODS: Data were collected through 17 focus groups (at 17 different schools...

  18. Barriers that do not fall

    OpenAIRE

    Velasco Arroyo, Juan Carlos

    2014-01-01

    * Full title: "Barriers that do not fall. Access to citizenship and the right to vote in a comparative perspective: Germany / Spain". * Presentation in Conference "Border Transgressions" - Bonn Universität (Germany) - 8-9th May 2014

  19. Engineered barriers: current status 1989

    International Nuclear Information System (INIS)

    This report summarises the current state of research relevant to assessing the performance of engineered barriers made of steel and concrete in radioactive waste repositories. The objective of these barriers is to contain substantially the radionuclides within them by providing both physical and chemical impediment to their release. The physical barriers are of most value for highly soluble isotopes with relatively short half-lives (eg 137Cs), since they can provide a measure of containment until a large fraction of the activity has decayed. In addition they can facilitate retrievability for some period after disposal. The chemical barriers operate by beneficial conditioning of the near field groundwater and providing sites for sorption of radionuclides. Both of these reduce the aqueous concentration of radionuclides in the near field. (author)

  20. Coastal Structures and Barriers 2012

    Data.gov (United States)

    California Department of Resources — This dataset is a compilation of the UCSC Sand Retention Structures, MC Barriers, and USACE Coastal Structures. UCSC Sand Retention Structures originate from a...

  1. Translating barriers into potential improvements

    DEFF Research Database (Denmark)

    Altintzoglou, Themistoklis; Hansen, Karina Birch; Valsdottir, Thora;

    2010-01-01

    Purpose: The aim of this study is to explore potential barriers to seafood consumption by The aim of this study is to explore potential barriers to seafood consumption by young adults and the parents of young children. Knowledge of these barriers will be used to assist the development of new....... Practical implications: Inputs for NPD related to convenience, attractiveness, quality, Inputs for NPD related to convenience, attractiveness, quality, trustworthiness, knowledge and requirements about seafood preparation are discussed. Originality/value: The present study combines qualitative methods to...... lead to practical input The present study combines qualitative methods to lead to practical input for NPD focusing on overcoming the barriers that keep consumers from choosing existing healthy seafood products. The importance of the consumers' confidence in their ability to successfully prepare a...

  2. Blood–brain barrier: a real obstacle for therapeutics

    Directory of Open Access Journals (Sweden)

    Shiekh FA

    2012-07-01

    Full Text Available Farooq A ShiekhAix-Marseille Université, URMITE, UMR, CNRS 7278, IRD 198, Marseille, FranceIn a recent report published in the International Journal of Nanomedicine, Gulati et al1 have described the most innovative study addressing an important issue of the "blood–brain barrier," which can act as a barrier to one of the fundamental goals of modern neurobiology that would have a direct impact on highly debated future therapeutics for both brain cancer and neurological disorders. Contrary to what has been the case with conventional therapy, the authors were able to completely bypass the blood–brain barrier (Figure 1 – a limiting factor for efficient drug delivery – by proposing a new, alternative approach using nanoengineered TNT/Ti implants for local delivery of chemotherapeutics such as doxorubicin into the brain. There must be millions of good drugs sitting in pharmaceutical company stores that cannot be delivered simply because they cannot get past the blood–brain barrier.2 This is an area that has been under-researched and its significance has not yet been recognized. Neuroscience textbooks bury this issue in the appendix, PhD programs give it a cursory treatment, and pharmaceutical companies have tried to ignore it. Despite the blood–brain barrier acting as a stubbornly real obstacle for potential drugs to be used against many disorders of the central nervous system, the field of drug delivery is advancing rapidly. View original paper by Gulati and colleagues.

  3. Aging and Phase Stability of Waste Package Outer Barrier

    Energy Technology Data Exchange (ETDEWEB)

    Tammy S. Edgecumble Summers

    2001-08-23

    This Analysis Model Report (AMR) was prepared in accordance with the Work Direction and Planning Document, ''Aging and Phase Stability of Waste Package Outer Barrier'' (CRWMS M&O 1999a). ICN 01 of this AMR was developed following guidelines provided in TWP-MGR-MD-000004 REV 01, ''Technical Work Plan for: Integrated Management of Technical Product Input Department'' (BSC 2001, Addendum B). It takes into consideration the Enhanced Design Alternative II (EDA II), which has been selected as the preferred design for the Engineered Barrier System (EBS) by the License Application Design Selection (LADS) program team (CRWMS M&O 1999b). The salient features of the EDA II design for this model are a waste package (WP) consisting of an outer barrier of Alloy 22 and an inner barrier of Type 316L stainless steel. This report provides information on the phase stability of Alloy 22l, the current waste-package-outer-barrier (WPOB) material. These phase stability studies are currently divided into three general areas: (1) Long-range order reactions; (2) Intermetallic and carbide precipitation in the base metal; and (3) Intermetallic and carbide precipitation in welded samples.

  4. Barriers to Effective Strategic Planning

    OpenAIRE

    Bilal Latif

    2012-01-01

    Despite the best intentions and a lot of hard work, strategic planning most predictably fails. It’s not that strategic planning is a bad idea but there are some barriers which involve in its failure. This paper explores how and where strategic planning goes awry and what executives can do about it. The study finds some of the most common barriers in effective strategic planning like, strict time limits, identical procedures, lack of accountability, power and influence which organizations freq...

  5. Barriers in diabetes self management

    OpenAIRE

    Rising, Carl Johan; Lauwersen, Asbjørn Flyger; Stoustrup, Sune Wiingaard

    2013-01-01

    This project seeks to expand on the question: What barriers may occur in diabetes patients' self-care, and how can doctors and patients communicate across professionalism? This project deals with the barrier that may arise between the transfer of highly professional knowledge and patient. The project seeks to create an understanding on how diabetes patients, which is the target audience, understands and experience their illness, and thereby mapping key elements for further focus, to better th...

  6. Superheavy nuclei and fission barriers

    Science.gov (United States)

    Lu, Bing-Nan; Zhao, Jie; Zhao, En-Guang; Zhou, Shan-Gui

    In this chapter, we will present relativistic mean field (RMF) description of heavy and superheavy nuclei (SHN). We will discuss the shell structure and magic numbers in the mass region of SHN, binding energies and α decay Q values, shapes of ground states and potential energy surfaces and fission barriers. We particularly focus on the multidimensionally-constrained covariant density functional theories (CDFT) and the applications of CDFT to the study of exotic nuclear shapes and fission barriers.

  7. Methods for Attribute Measurement and Alternatives to Multiplicity Counting

    International Nuclear Information System (INIS)

    The Attribute Measurement System with Information Barrier (AMS/IB) specification is being developed in support of the Defense Threat Reduction Agency's (DTRA's) Cooperative Threat Reduction (CTR) program for the Mayak Fissile Material Storage Facility. This document discusses the technologies available for attribute measurement, and advantages and disadvantages of alternatives

  8. Verification of the integrity of barriers using gas diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Ward, D.B. [SPECTRA Research Inst., Albuquerque, NM (United States); Williams, C.V. [Sandia National Labs., Albuquerque, NM (United States). Environmental Restoration Technologies Dept.

    1997-06-01

    In-situ barrier materials and designs are being developed for containment of high risk contamination as an alternative to immediate removal or remediation. The intent of these designs is to prevent the movement of contaminants in either the liquid or vapor phase by long-term containment, essentially buying time until the contaminant depletes naturally or a remediation can be implemented. The integrity of the resultant soil-binder mixture is typically assessed by a number of destructive laboratory tests (leaching, compressive strength, mechanical stability with respect to wetting and freeze-thaw cycles) which as a group are used to infer the likelihood of favorable long-term performance of the barrier. The need exists for a minimally intrusive yet quantifiable methods for assessment of a barrier`s integrity after emplacement, and monitoring of the barrier`s performance over its lifetime. Here, the authors evaluate non-destructive measurements of inert-gas diffusion (specifically, SF{sub 6}) as an indicator of waste-form integrity. The goals of this project are to show that diffusivity can be measured in core samples of soil jet-grouted with Portland cement, validate the experimental method through measurements on samples, and to calculate aqueous diffusivities from a series of diffusion measurements. This study shows that it is practical to measure SF{sub 6} diffusion rates in the laboratory on samples of grout (Portland cement and soil) typical of what might be used in a barrier. Diffusion of SF{sub 6} through grout (Portland cement and soil) is at least an order of magnitude slower than through air. The use of this tracer should be sensitive to the presence of fractures, voids, or other discontinuities in the grout/soil structure. Field-scale measurements should be practical on time-scales of a few days.

  9. Global interrupt and barrier networks

    Science.gov (United States)

    Blumrich, Matthias A.; Chen, Dong; Coteus, Paul W.; Gara, Alan G.; Giampapa, Mark E; Heidelberger, Philip; Kopcsay, Gerard V.; Steinmacher-Burow, Burkhard D.; Takken, Todd E.

    2008-10-28

    A system and method for generating global asynchronous signals in a computing structure. Particularly, a global interrupt and barrier network is implemented that implements logic for generating global interrupt and barrier signals for controlling global asynchronous operations performed by processing elements at selected processing nodes of a computing structure in accordance with a processing algorithm; and includes the physical interconnecting of the processing nodes for communicating the global interrupt and barrier signals to the elements via low-latency paths. The global asynchronous signals respectively initiate interrupt and barrier operations at the processing nodes at times selected for optimizing performance of the processing algorithms. In one embodiment, the global interrupt and barrier network is implemented in a scalable, massively parallel supercomputing device structure comprising a plurality of processing nodes interconnected by multiple independent networks, with each node including one or more processing elements for performing computation or communication activity as required when performing parallel algorithm operations. One multiple independent network includes a global tree network for enabling high-speed global tree communications among global tree network nodes or sub-trees thereof. The global interrupt and barrier network may operate in parallel with the global tree network for providing global asynchronous sideband signals.

  10. Barriers to Banking - Towards an Inclusive Banking Environment in South Africa.

    Science.gov (United States)

    Martinson, Estelle; Martinson, Johannes

    2016-01-01

    A recent study in South Africa on the barriers to banking which involved customers in three disability groups namely mobility, hearing and vision has highlighted that currently banking in South Africa is not accessible. Customers with a disability are unable to independently use banking services across a wide range of channels. Exclusion from something as fundamental as managing their own financial affairs raise serious human rights concerns and requires committed action from decision-makers to address this. The fact that solutions to all of the identified barriers have been successfully implemented in banks in other parts of the world for many years emphasize that this is not a technical challenge. While some solutions require complex or expensive changes such as removing physical access barriers and ensuring that digital channels meet internationally accepted standards of accessibility, there are many simple and low-cost solutions which can be implemented immediately and would make a world of difference to these customers and their experience of banking. One key barrier which emerged in all the focus groups and surveys is attitudinal barriers - staff who are unwilling to assist, impatient, interact with the customer's assistant instead of directly with them and lack basic skills on how to interact with someone who has a disability. A comprehensive framework of banking was used to identify a wide range of barriers. The barriers were classified as attitudinal, barriers to physical access, digital access barriers, barriers to information, communication barriers and some generic concerns such as safe evacuation during emergencies and alternative authentication. Both the barriers and the solutions where ranked by participants. From a theoretical perspective, the benefit of a customer-centric approach to understanding these barriers and the innovation potential of a Universal Design approach is affirmed by this study. PMID:27534346

  11. Demonstration of close-coupled barriers for subsurface containment of buried waste

    International Nuclear Information System (INIS)

    A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin inner lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed waste remediation plan. This paper discusses the installation of a close-coupled barrier and the subsequent integrity verification. The demonstration was installed at a benign site at the Hanford Geotechnical Test Facility, 400 Area, Hanford, Washington. The composite barrier was emplaced beneath a 7,500 liter tank. The tank was chosen to simulate a typical DOE Complex waste form. The stresses induced on the waste form were evaluated during barrier construction. The barrier was constructed using conventional jet grouting techniques. Drilling was completed at a 45 degree angle to the ground, forming a conical shaped barrier with the waste form inside the cone. Two overlapping rows of cylindrical cement columns were grouted in a honeycomb fashion to form the secondary backdrop barrier layer. The primary barrier, a high molecular weight polymer manufactured by 3M Company, was then installed providing a relatively thin inner liner for the secondary barrier. The primary barrier was emplaced by panel jet grouting with a dual wall drill stem, two phase jet grouting system

  12. Polyphase alternating codes

    CERN Document Server

    Markkanen, Markku

    2007-01-01

    This work introduces a method for constructing polyphase alternating codes in which the length of a code transmission cycle can be $p^m$ or $p-1$, where $p$ is a prime number and $m$ is a positive integer. The relevant properties leading to the construction alternating codes and the algorithm for generating alternating codes is described. Examples of all practical and some not that practical polyphase code lengths are given.

  13. Alternative Solar Indices

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, L.J.

    1980-07-01

    Possible alternative Solar Indices which could either be a perturbation from the currently defined Solar Index or possible indices based on current technologies for other media markets are discussed. An overview is given of the current project, including the logic that was utilized in defining its current structure and then alternative indices and definitions are presented and finally, recommendations are made for adopting alternative indices.

  14. On an Alternative Cosmology

    OpenAIRE

    Vankov, A.

    1998-01-01

    The suggested alternative cosmology is based on the idea of barion symmetric universe, in which our home universe is a representative of multitude of typical matter and antimatter universes. This alternative concept gives a physically reasonable explanation of all major problems of the Standard Cosmological Model. Classification Code MSC: Cosmology 524.8 Key words: standard cosmological model, alternative cosmology, barionic symmetry, typical universe, quasars, cosmic rays.

  15. Complex Alternative Splicing

    OpenAIRE

    Park, Jung Woo; Graveley, Brenton R.

    2007-01-01

    Alternative splicing is a powerful means of controlling gene expression and increasing protein diversity. Most genes express a limited number of mRNA isoforms, but there are several examples of genes that use alternative splicing to generate hundreds, thousands, and even tens of thousands of isoforms. Collectively such genes are considered to undergo complex alternative splicing. The best example is the Drosophila Down syndrome cell adhesion molecule (Dscam) gene, which can generate 38,016 is...

  16. Promotional issues on alternative energy technologies in Nepal

    International Nuclear Information System (INIS)

    Alternative energy technologies are being disseminated in many countries with an objective to reduce the uses of traditional and commercial energy sources. These technologies convert local resources to usable energy forms. Since the scale of these technologies is small, their implementation is targeted mainly to individual households or small communities. However, due to various constraints, these implementation programmes have not been very successful. In this paper, the author introduces the main characteristics of alternative energy technologies used in Nepal and discusses promotional barriers for their implementation. It is hoped that this paper would help energy policy makers to devise better alternative energy programmes

  17. Epithelial barrier and ion transport in coeliac sprue: electrical measurements on intestinal aspiration biopsy specimens.

    OpenAIRE

    Schulzke, J D; Schulzke, I; Fromm, M.; Riecken, E O

    1995-01-01

    Epithelial barrier function and ion transport was studied in coeliac sprue using a miniaturised Ussing device for measurements on diagnostic aspiration biopsy specimens from the jejunum of untreated or gluten free nourished sprue patients, or from healthy controls. Pure epithelial resistance (Re) indicating epithelial barrier function was determined by transmural alternating current impedance analysis. It was reduced by 56% in acute sprue mean (SEM) (9 (1) omega.cm2) compared with controls (2...

  18. Alternators. Experience feedback

    International Nuclear Information System (INIS)

    Study of the technical aspects of various accidents having occured on nuclear alternators operating in the French 900 MW nuclear plant unit, and the respective solutions and possibilities for application to alternators of the 1000 and 1500 MW power plants. Analysis of the accidents on CP 1 program alternators: accidents caused by vibratory fatigue (cracking of the hydraulic connection pipes of the stator winding, cracking of the hydraulic-electric connection between the stator coiling and the output terminals, cracking of the hydrogen cooler finned tubes), pollution by copper oxide of the stator winding cooling water circuit. Accidents on CP 2 alternators: accident on the shaft sealing joint, striking inside the terminal box

  19. Diabetes and diet: Managing dietary barriers.

    NARCIS (Netherlands)

    Friele, R.D.

    1989-01-01

    This thesis reports on the barriers diabetic patients experience with their diet, and the ways they cope with these barriers. A dietary barrier is a hinderance to a person's well-being, induced by being advised a diet. First inventories were made of possible dietary barriers and ways of coping with

  20. Engineered Barriers and Geological Disposal

    International Nuclear Information System (INIS)

    A geological disposal system comprises a system of multiple barriers, both natural and man-made, to provide long-term isolation and containment of radioactive waste. Various geological formations are stable and potentially suitable for geological disposal. Engineered barriers are designed to work in an integrated fashion together with the host geological formation. Much research has been carried out to develop engineered barrier systems suitable for use in different host rocks and with different waste types. These studies continue both nationally and within the framework of multilateral international projects, in facilities such as underground research laboratories. Geological disposal is the preferred method for long term management of radioactive waste. In each repository the long-term isolation and containment of the waste is achieved by the host geological formation and the system of engineered barriers. Any engineered barrier system (EBS) is made of several components, each taking different safety roles that are relied upon at different times in the lifetime of the repository. Research, demonstration and development of EBS materials, as well as of their manufacturing and emplacement technologies are important endeavours in national waste management programmes and the subject of international cooperation. These studies and demonstrations have considerably enhanced confidence in the production of the EBS components and in their performance under repository conditions

  1. Cytokines and the Skin Barrier

    Directory of Open Access Journals (Sweden)

    Jens Malte Baron

    2013-03-01

    Full Text Available The skin is the largest organ of the human body and builds a barrier to protect us from the harmful environment and also from unregulated loss of water. Keratinocytes form the skin barrier by undergoing a highly complex differentiation process that involves changing their morphology and structural integrity, a process referred to as cornification. Alterations in the epidermal cornification process affect the formation of the skin barrier. Typically, this results in a disturbed barrier, which allows the entry of substances into the skin that are immunologically reactive. This contributes to and promotes inflammatory processes in the skin but also affects other organs. In many common skin diseases, including atopic dermatitis and psoriasis, a defect in the formation of the skin barrier is observed. In these diseases the cytokine composition within the skin is different compared to normal human skin. This is the result of resident skin cells that produce cytokines, but also because additional immune cells are recruited. Many of the cytokines found in defective skin are able to influence various processes of differentiation and cornification. Here we summarize the current knowledge on cytokines and their functions in healthy skin and their contributions to inflammatory skin diseases.

  2. Penetration through the Skin Barrier.

    Science.gov (United States)

    Nielsen, Jesper Bo; Benfeldt, Eva; Holmgaard, Rikke

    2016-01-01

    The skin is a strong and flexible organ with barrier properties essential for maintaining homeostasis and thereby human life. Characterizing this barrier is the ability to prevent some chemicals from crossing the barrier while allowing others, including medicinal products, to pass at varying rates. During recent decades, the latter has received increased attention as a route for intentionally delivering drugs to patients. This has stimulated research in methods for sampling, measuring and predicting percutaneous penetration. Previous chapters have described how different endogenous, genetic and exogenous factors may affect barrier characteristics. The present chapter introduces the theory for barrier penetration (Fick's law), and describes and discusses different methods for measuring the kinetics of percutaneous penetration of chemicals, including in vitro methods (static and flow-through diffusion cells) as well as in vivo methods (microdialysis and microperfusion). Then follows a discussion with examples of how different characteristics of the skin (age, site and integrity) and of the penetrants (size, solubility, ionization, logPow and vehicles) affect the kinetics of percutaneous penetration. Finally, a short discussion of the advantages and challenges of each method is provided, which will hopefully allow the reader to improve decision making and treatment planning, as well as the evaluation of experimental studies of percutaneous penetration of chemicals. PMID:26844902

  3. Transport barriers in helical systems

    International Nuclear Information System (INIS)

    There are some publications with indications that the formation of transport barriers in toroidal devices could take place in the vicinity of low order rational surfaces (RS). It is necessary to note that the environs of RS have very important peculiarities. In particular, a stochastic layer of magnetic field lines forms instead of separaterix which must separate the island surfaces from the adjacent to them non-island surfaces in stellarator magnetic configurations. The attempt to realize the formation of transport barriers near RS and to study their influence on the RF discharge plasma confinement was undertaken in presented experiments on the U-3M torsatron. The presupposition was made that the radial electric field profile would have sharp change on the width of stochastic layer near RS in the case of collisionless longitudinal motion of electrons in this layer. Experimental data obtained on the U-3M torsatron during the formation of interior and edge transport barriers are in a good agreement with this presupposition. The results of experiments on the U-3M torsatron are discussed in comparison with data of other helical systems. It is shown that the number of dependences (the threshold power and density, the time of barrier formation, the localization of radial electric field shear layer) are in a good agreement for all these systems. In conclusion, the common features of formation of transport barriers in non- axisymmetric and non-axisymmetric systems are discussed. (author)

  4. The complex influences of back-barrier deposition, substrate slope and underlying stratigraphy in barrier island response to sea-level rise: Insights from the Virginia Barrier Islands, Mid-Atlantic Bight, U.S.A.

    Science.gov (United States)

    Brenner, Owen T.; Moore, Laura J.; Murray, A. Brad

    2015-10-01

    To understand the relative importance of back barrier environment, substrate slope and underlying stratigraphy in determining barrier island response to RSLR (relative sea-level rise), we use a morphological-behavior model (GEOMBEST) to conduct a series of sensitivity experiments, based on late-Holocene hindcast simulations of an island in the U.S. mid-Atlantic Bight (Metompkin Island, VA) having both salt marsh and lagoonal back-barrier environments, and we draw comparisons between these results and future simulations (2000-2100 AD) of island response to RSLR. Sensitivity analyses indicate that, as a whole, the island is highly sensitive to factors that reduce overall sand availability (i.e., high sand-loss rates and substrates containing little sand). Results also indicate that for all predicted future RSLR scenarios tested, islands having high substrate sand proportions (if allowed to migrate freely) will likely remain subaerial for centuries because of sufficient substrate sand supply and elevation to assist in keeping islands above sea level. Simulation results also lead to basic insights regarding the interactions among substrate slope, back-barrier deposition and island migration rates. In contrast to previous studies, which suggest that changes in substrate slope directly affect the island migration trajectory, we find that-in the presence of back-barrier deposition-the connection between substrate slope and island behavior is modulated (i.e., variability in migration rates is dampened) by changes in back-barrier width. These interactions-which tend to produce changes in shoreface sand content-lead to a negative feedback when the back-barrier deposit contains less sand than the underlying layer, resulting in a stable back-barrier width. Alternatively, a positive feedback arises when the back-barrier deposit contains more sand than the underlying layer, resulting in either back-barrier disappearance or perpetual widening.

  5. Programmer's description of the Barrier Data Base

    International Nuclear Information System (INIS)

    The Barrier Data Base is a body of information concerning different kinds of barriers that are used in safeguarding nuclear materials and installations. The two programs written for creating, updating, and manipulating the Barrier Data Base are discussed. The BARRIER program is used to add, delete, modify, display, or search for specific data in the data base. A utility program named NUMBER is used to compress and renumber the barrier and threat tables

  6. Alternative Devices for Taking Insulin

    Science.gov (United States)

    ... KB). Alternate Language URL Alternative Devices for Taking Insulin Page Content On this page: What alternative devices ... the skin. [ Top ] What alternative devices for taking insulin are available? Insulin pens provide a convenient, easy- ...

  7. Brandmodstandsbidrag for alternative isoleringsmaterialer

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2001-01-01

    Resume af rapport om alternative isoleringsmaterialers brandmodstandsbidrag, udarbejdet af Dansk Brandteknisk Institut under Energistyrelsens udviklingsprogram "Miljø- og arbejdsmiljøvenlig isolering"......Resume af rapport om alternative isoleringsmaterialers brandmodstandsbidrag, udarbejdet af Dansk Brandteknisk Institut under Energistyrelsens udviklingsprogram "Miljø- og arbejdsmiljøvenlig isolering"...

  8. Anvendelse af alternative isoleringsmaterialer

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2003-01-01

    Resume af By og Byg Anvisning 207 om anvendelse af alternative isoleringsmaterialer, udarbejdet af Statens Byggeforskningsinstitut under udviklingsprogrammet "Miljø- og arbejdsmiljøvenlig isolering"......Resume af By og Byg Anvisning 207 om anvendelse af alternative isoleringsmaterialer, udarbejdet af Statens Byggeforskningsinstitut under udviklingsprogrammet "Miljø- og arbejdsmiljøvenlig isolering"...

  9. Structure information from fusion barriers

    Indian Academy of Sciences (India)

    S V S Sastry; S Santra

    2000-06-01

    It is shown that the analysis of fusion barrier distributions is not always an unambiguous test or a ‘fingerprint’ of the structure information of the colliding nuclei. Examples are presented with same fusion barrier distributions for nuclei having different structures. The fusion excitation functions for 16O+208Pb, using the coupled reaction channel (CRC) method and correct structure information, have been analysed. The barrier distributions derived from these excitation functions including many of the significant channels are featureless, although these channels have considerable effects on the fusion excitation function. However, a simultaneous analysis of the fusion, elastic and quasi-elastic channels would fix the structure and the reaction unambiguously

  10. Barriers to Effective Strategic Planning

    Directory of Open Access Journals (Sweden)

    Bilal Latif

    2012-12-01

    Full Text Available Despite the best intentions and a lot of hard work, strategic planning most predictably fails. It’s not that strategic planning is a bad idea but there are some barriers which involve in its failure. This paper explores how and where strategic planning goes awry and what executives can do about it. The study finds some of the most common barriers in effective strategic planning like, strict time limits, identical procedures, lack of accountability, power and influence which organizations frequently face in strategy formulation and implementation. It is concluded that, in order to achieve the goal of effective strategic planning, effective change management and leadership are indispensable. On the one hand, it is mandatory for the leadership to involve employees in decision making process, along with the explicit description of their roles within the organization, and on the other hand, full mechanism of employees’ accountability and regular checks are required to remove these barriers.

  11. The Solution to Green Barrier

    Institute of Scientific and Technical Information of China (English)

    Cui Yan

    2009-01-01

    @@ The recovery process of world economy is rough and full of twists and turns.Especially the trade protectionism,having reemerged under the mask of"green barrier",is making a great impact on the slowly recovering world economy and trade.Then,what are the characteristics of trade barriers in the post-crisis era?Where is the outlet of Chinese manufacturing industry?With these questions,ourreporter interviewed Professor Zhou Shijian,Standing Director to China Association of International Trade and Senior Researcher to SINO-US Relationship Research Centre of Tsinghua University.

  12. Migration barrier covers for radioactive and mixed waste landfills

    International Nuclear Information System (INIS)

    Migration barrier cover technology will likely serve as the remediation alternative of choice for most of DOE's radioactive and mixed waste landfills simply because human and ecological risks can be effectively managed without the use of more expensive alternatives. However, very little testing and evaluation has been done, either before or after installation, to monitor how effective they are in isolating waste or to develop data that can be used to evaluate model predictions of long term performance. Los Alamos National Laboratory has investigated the performance of a variety of landfill capping alternatives since 1981 using large field lysimeters to monitor the fate of precipitation falling on the cap surface. The objective of these studies is to provide the risk manager with a variety of field tested capping designs, of various complexities and costs, so that design alternatives can be matched to the need for hydrologic control at the site. Four different landfill cap designs, representing different complexities and costs, were constructed at Hill Air Force Base (AFB) in October and November, 1989. The designs were constructed in large lysimeters and instrumented to provide estimates of all components of water balance including precipitation, runoff (and soil erosion), infiltration, leachate production, evapotranspiration, and capillary/hydraulic barrier flow. The designs consisted of a typical soil cover to serve as a baseline, a modified EPA RCRA cover, and two versions of a Los Alamos design that contained erosion control measures, an improved vegetation cover to enhance evapotranspiration, and a capillary barrier to divert downward flow of soil water. A comprehensive summary of the Hill AFB demonstration will be available in October 1993, when the project is scheduled to terminate

  13. Barriers to renewable energy development: A case study of large-scale wind energy in Saskatchewan, Canada

    International Nuclear Information System (INIS)

    Renewable energy is receiving increased attention as a viable alternative to non-renewable electrical generation, however, meeting global energy demands will require a more ambitious renewable energy program than is currently the case. There have been several reviews of potential technological, economic, social, or public barriers and solutions to renewable energy investment. Although important, there is also need for multi-dimensional analyses of these barriers and identification of the most significant underlying barriers if viable solutions are to be developed. In this paper we apply a theoretical framework to examine stakeholder's perceptions and understanding of the barriers to wind energy development in Saskatchewan, Canada. We identify and examine the most significant underlying barriers to investment in renewable energy and the interactions between those barriers. Results show a number of perceived barriers to wind energy investment, however, these barriers can be explained in large part by knowledge barriers, if not disagreement over whether the current level of investment in wind energy is sufficient. We show that barriers to renewable energy cannot be explained solely by technological, social, political, or economic factors in isolation, and that a multi-dimensional approach, identifying and explaining the underlying sources of these barriers, is necessary to develop viable solutions. - Highlights: ► Meeting future wind energy objectives requires an ambitious investment program. ► A framework is applied to identify and explain perceived barriers to wind energy. ► Stakeholders perceived technological and political barriers as the most significant. ► These could be explained by knowledge barriers and complacency with the status quo. ► Even with additional investment these underlying barriers will constrain progress.

  14. Alternative loop rings

    CERN Document Server

    Goodaire, EG; Polcino Milies, C

    1996-01-01

    For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

  15. On the performance of capillary barriers as landfill cover

    Science.gov (United States)

    Kämpf, M.; Montenegro, H.

    Landfills and waste heaps require an engineered surface cover upon closure. The capping system can vary from a simple soil cover to multiple layers of earth and geosynthetic materials. Conventional design features a compacted soil layer, which suffers from drying out and cracking, as well as root and animal intrusion. Capillary barriers consisting of inclined fine-over-coarse soil layers are investigated as an alternative cover system. Under unsaturated conditions, the textural contrast delays vertical drainage by capillary forces. The moisture that builds up above the contact will flow downdip along the interface of the layers. Theoretical studies of capillary barriers have identified the hydraulic properties of the layers, the inclination angle, the length of the field and the infiltration rate as the fundamental characteristics of the system. However, it is unclear how these findings can lead to design criteria for capillary barriers. To assess the uncertainty involved in such approaches, experiments have been carried out in a 8 m long flume and on large scale test sites (40 m x 15 m). In addition, the ability of a numerical model to represent the relevant flow processes in capillary barriers has been examined.

  16. Architectural Barriers Removal: Resource Guide.

    Science.gov (United States)

    Office of Human Development (DHEW), Washington, DC. Office for Handicapped Individuals.

    The guide presents information on resources for eliminating architectural barriers for handicapped persons. Entries are grouped according to information resources, funding sources, and publications available from the federal government. Seven organizations are described in terms of agency goals, publications, and materials. Federal programs…

  17. Injectable barriers for waste isolation

    International Nuclear Information System (INIS)

    In this paper the authors report laboratory work and numerical simulation done in support of development and demonstration of injectable barriers formed from either of two fluids: colloidal silica or polysiloxane. Two principal problems addressed here are control of gel time and control of plume emplacement in the vadose zone. Gel time must be controlled so that the viscosity of the barrier fluid remains low long enough to inject the barrier, but increases soon enough to gel the barrier in place. During injection, the viscosity must be low enough to avoid high injection pressures which could uplift or fracture the formation. To test the grout gel time in the soil, the injection pressure was monitored as grouts were injected into sandpacks. When grout is injected into the vadose zone, it slumps under the influence of gravity, and redistributes due to capillary forces as it gels. The authors have developed a new module for the reservoir simulator TOUGH2 to model grout injection into the vadose zone, taking into account the increase of liquid viscosity as a function of gel concentration and time. They have also developed a model to calculate soil properties after complete solidification of the grout. The numerical model has been used to design and analyze laboratory experiments and field pilot tests. The authors present the results of computer simulations of grout injection, redistribution, and solidification

  18. Injectable barriers for waste isolation

    Energy Technology Data Exchange (ETDEWEB)

    Persoff, P.; Finsterle, S.; Moridis, G.J.; Apps, J.; Pruess, K. [Lawrence Berkeley National Lab., CA (United States). Earth Sciences Div.; Muller, S.J. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering

    1995-03-01

    In this paper the authors report laboratory work and numerical simulation done in support of development and demonstration of injectable barriers formed from either of two fluids: colloidal silica or polysiloxane. Two principal problems addressed here are control of gel time and control of plume emplacement in the vadose zone. Gel time must be controlled so that the viscosity of the barrier fluid remains low long enough to inject the barrier, but increases soon enough to gel the barrier in place. During injection, the viscosity must be low enough to avoid high injection pressures which could uplift or fracture the formation. To test the grout gel time in the soil, the injection pressure was monitored as grouts were injected into sandpacks. When grout is injected into the vadose zone, it slumps under the influence of gravity, and redistributes due to capillary forces as it gels. The authors have developed a new module for the reservoir simulator TOUGH2 to model grout injection into the vadose zone, taking into account the increase of liquid viscosity as a function of gel concentration and time. They have also developed a model to calculate soil properties after complete solidification of the grout. The numerical model has been used to design and analyze laboratory experiments and field pilot tests. The authors present the results of computer simulations of grout injection, redistribution, and solidification.

  19. Overcoming Barriers: Women in Superintendency

    Science.gov (United States)

    Miller, Claire M.

    2009-01-01

    Women currently represent the largest number of teachers in the United States but remain underrepresented in the superintendent position. This suggests that the superintendency has been influenced by patriarchy. If women are to break through the barriers that prevent them from attaining a superintendency, we will need to understand the social…

  20. Communities Address Barriers to Connectivity.

    Science.gov (United States)

    Byers, Anne

    1996-01-01

    Rural areas lag behind urban areas in access to information technologies. Public institutions play a critical role in extending the benefits of information technologies to those who would not otherwise have access. The most successful rural telecommunications plans address barriers to use, such as unawareness of the benefits, technophobia, the…

  1. The blood-brain barrier.

    Science.gov (United States)

    Obermeier, Birgit; Verma, Ajay; Ransohoff, Richard M

    2016-01-01

    In autoimmune neurologic disorders, the blood-brain barrier (BBB) plays a central role in immunopathogenesis, since this vascular interface is an entry path for cells and effector molecules of the peripheral immune system to reach the target organ, the central nervous system (CNS). The BBB's unique anatomic structure and the tightly regulated interplay of its cellular and acellular components allow for maintenance of brain homeostasis, regulation of influx and efflux, and protection from harm; these ensure an optimal environment for the neuronal network to function properly. In both health and disease, the BBB acts as mediator between the periphery and the CNS. For example, immune cell trafficking through the cerebral vasculature is essential to clear microbes or cell debris from neural tissues, while poorly regulated cellular transmigration can underlie or worsen CNS pathology. In this chapter, we focus on the specialized multicellular structure and function of the BBB/neurovascular unit and discuss how BBB breakdown can precede or be a consequence of neuroinflammation. We introduce the blood-cerebrospinal fluid barrier and include a brief aside about evolutionary aspects of barrier formation and refinements. Lastly, since restoration of barrier function is considered key to ameliorate neurologic disease, we speculate about new therapeutic avenues to repair a damaged BBB. PMID:27112670

  2. Seal design alternatives study

    International Nuclear Information System (INIS)

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information

  3. Seal design alternatives study

    Energy Technology Data Exchange (ETDEWEB)

    Van Sambeek, L.L. [RE/SPEC Inc., Rapid City, SD (US); Luo, D.D.; Lin, M.S.; Ostrowski, W.; Oyenuga, D. [Parsons Brinckerhoff Quade & Douglas, Inc., San Francisco, CA (US)

    1993-06-01

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information.

  4. An alternative currency

    OpenAIRE

    Frendo, Mario; Duca, Edward

    2013-01-01

    Malta- a tiny island, a minute social reality, a precursory canovaccio of European unification- has a unique asset it ought to be prouder of: culture. http://www.um.edu.mt/think/an-alternative-currency/

  5. Alternatives to Nursing Homes

    Science.gov (United States)

    ... this website may not be available. Alternatives to nursing homes Before you make any decisions about long ... live and what help you may need. A nursing home may not be your only choice. Discharge ...

  6. Vaginal dryness alternative treatments

    Science.gov (United States)

    ... a day. Soybeans contain plant-based substances called isoflavones. These substances have an effect on the body ... soy for vasomotor symptoms: the Herbal Alternatives for Menopause (HALT) Study. Menopause . 2008;15(1):51-58. ...

  7. Alternative fuel information sources

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    This short document contains a list of more than 200 US sources of information (Name, address, phone number, and sometimes contact) related to the use of alternative fuels in automobiles and trucks. Electric-powered cars are also included.

  8. The alternative library

    OpenAIRE

    Collinson, Timothy; A. Williams

    2004-01-01

    Much time and effort has been devoted to designing and developing library Web sites that are easy to navigate by both new students and experienced researchers. In a review of the Southampton Institute Library it was decided that in addition to updating the existing homepage an alternative would be offered. Drawing on theory relating to user interface design, learning styles and creative thinking, an Alternative Library navigation system was added to the more traditional library homepage. The ...

  9. Alternative fuel cycles

    International Nuclear Information System (INIS)

    Uranium resource utilization and economic considerations provide incentives to study alternative fuel cycles as future options to the PHWR natural uranium cycle. Preliminary studies to define the most favourable alternatives and their possible introduction dates are discussed. The important and uncertain components which influence option selection are reviewed, including nuclear capacity growth, uranium availability and demand, economic potential, and required technological developments. Finally, a summary of Ontario Hydro's program to further assess cycle selection and define development needs is given. (auth)

  10. Ultimacy and alternative possibilities

    OpenAIRE

    Fischer, John Martin

    2009-01-01

    I explore a key feature of Robert Kane’s libertarianism (about which I have been puzzled for some time). Kane claims that we should separate issues of alternative possibilities from issues of ultimacy, but he further argues that they are connected in a certain way. I call into question this connection, and I continue to argue for a strict separation of considerations pertaining to alternative possibilities and “actual-sequence” considerations.

  11. Des divisions aux alternances

    Directory of Open Access Journals (Sweden)

    Eric Clemens

    2012-12-01

    Full Text Available - From the divisions to the alternations - Society, action and common good give sense to democracy. Society is in fact a set of unmitigated divisions (horizontal and vertical, material and symbolic. Democratic action, since the discourse’s conflicts, doesn’t change the human beings, but things between they, in the alternation of power’s institutions for our only good in common: the body. With this aim, the Basic Income Earth Network is necessary.

  12. Barriers to Physical Activity Among Gay Men.

    Science.gov (United States)

    Cary, Miranda A; Brittain, Danielle R; Dinger, Mary K; Ford, Melissa L; Cain, Meagan; Sharp, Teresa A

    2016-09-01

    Gay men may not be physically active at recommended levels to achieve health benefits. Thus, a need exists to identify general (i.e., common across populations) and population-specific barriers that hinder or stop gay men from participating in physical activity (PA). Salient barriers may be identified through the extent each barrier limits PA (i.e., barrier limitation) and the level of one's confidence to overcome barriers and engage in PA (i.e., self-regulatory efficacy). The purposes of this study were to (1) provide a description of general and population-specific barriers to PA among sufficiently and insufficiently active gay men, (2) identify barrier limitation and self-regulatory efficacy for the reported barriers, and (3) examine the associations between meeting the current PA recommendation, barrier limitation, and self-regulatory efficacy. Participants were 108 self-identified gay males aged 21 to 64 years who completed a web-based survey. A total of 35 general barriers and no population-specific barriers were identified by the sufficiently and insufficiently active groups. The sufficiently active group reported higher self-regulatory efficacy and lower barrier limitation for nearly all reported barriers. A binary logistic regression used to examine the associations between PA, barrier limitation, and self-regulatory efficacy was statistically significant, χ(2)(2, N = 108) = 19.26, p < .0001, R(2) = .16. Only barrier limitation significantly contributed to the model. Future research should continue to examine barriers to PA among gay men to determine whether an intervention needs to be designed specifically for gay men or whether a one-size-fits-all intervention would be effective in helping all men overcome common barriers to engaging in PA. PMID:25643585

  13. Barriers to improvements in energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.K.N.

    1991-10-01

    To promote energy-efficiency improvements, actions may be required at one or more levels -- from the lowest level of the consumer (residential, commercial, industrial, etc.) through the highest level of the global agencies. But barriers to the implementation of energy-efficiency improvements exist or can arise at all these levels. Taking up each one of these barriers in turn, the paper discusses specific measures that can contribute to overcoming the barriers. However, a one-barrier-one-measure approach must be avoided. Single barriers may in fact involve several sub-barriers. Also, combinations of measures are much more effective in overcoming barriers. In particular, combinations of measures that simultaneously overcome several barriers are most successful. The paper discusses the typology of barriers, explores their origin and suggests measures that by themselves or in combination with other measures, will overcome these barriers. Since most of the barriers dealt with can be found in the ``barriers`` literature, any originality in the paper lies in its systematic organization, synoptic view and holistic treatment of this issue. This paper is intended to initiate a comprehensive treatment of barriers, their origins and the measures that contribute to overcoming them. Hopefully, such a treatment will facilitate the implementation of energy-efficiency improvements involving a wide diversity of ever-changing energy end uses and consumer preferences.

  14. Barriers to improvements in energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.K.N.

    1991-10-01

    To promote energy-efficiency improvements, actions may be required at one or more levels -- from the lowest level of the consumer (residential, commercial, industrial, etc.) through the highest level of the global agencies. But barriers to the implementation of energy-efficiency improvements exist or can arise at all these levels. Taking up each one of these barriers in turn, the paper discusses specific measures that can contribute to overcoming the barriers. However, a one-barrier-one-measure approach must be avoided. Single barriers may in fact involve several sub-barriers. Also, combinations of measures are much more effective in overcoming barriers. In particular, combinations of measures that simultaneously overcome several barriers are most successful. The paper discusses the typology of barriers, explores their origin and suggests measures that by themselves or in combination with other measures, will overcome these barriers. Since most of the barriers dealt with can be found in the barriers'' literature, any originality in the paper lies in its systematic organization, synoptic view and holistic treatment of this issue. This paper is intended to initiate a comprehensive treatment of barriers, their origins and the measures that contribute to overcoming them. Hopefully, such a treatment will facilitate the implementation of energy-efficiency improvements involving a wide diversity of ever-changing energy end uses and consumer preferences.

  15. TRAGEN: Computer program to simulate an aircraft steered to follow a specified verticle profile. User's guide

    Science.gov (United States)

    1983-01-01

    The longitudinal dynamics of a medium range twin-jet or tri-jet transport aircraft are simulated. For the climbing trajectory, the thrust is constrained to maximum value, and for descent, the thrust is set at idle. For cruise, the aircraft is held in the trim condition. For climb or descent, the aircraft is steered to follow either (a) a fixed profile which is input to the program or (b) a profile computed at the beginning of that segment of the run. For climb, the aircraft is steered to maintain the given airspeed as a function of altitude. For descent, the aircraft is steered to maintain the given altitude as a function of range-to-go. In both cases, the control variable is angle-of-attack. The given output trajectory is presented and compared with the input trajectory. Step climb is treated just as climb. For cruise, the Breguet equations are used to compute the fuel burned to achieve a given range and to connect given initial and final values of altitude and Mach number.

  16. Informatization barriers of logistics process management in production company

    Directory of Open Access Journals (Sweden)

    Joanna WALASEK

    2015-09-01

    Full Text Available This article is an attempt to characterize informatization barriers of logistics processes management in a production company which provides automotive parts. Threats of successful implementation of Enterprise Resource Planning Systems include: community barriers; organizational barriers; communication barriers; formal barriers; legal barriers; not prepared implementation team barrier; substantive barrier. Proper identification of barriers and solving them are the right way to implement Enterprise Resource Planning Systems in a company.

  17. Engineered Barrier System Degradation, Flow, and Transport Process Model Report

    Energy Technology Data Exchange (ETDEWEB)

    E.L. Hardin

    2000-07-17

    The Engineered Barrier System Degradation, Flow, and Transport Process Model Report (EBS PMR) is one of nine PMRs supporting the Total System Performance Assessment (TSPA) being developed by the Yucca Mountain Project for the Site Recommendation Report (SRR). The EBS PMR summarizes the development and abstraction of models for processes that govern the evolution of conditions within the emplacement drifts of a potential high-level nuclear waste repository at Yucca Mountain, Nye County, Nevada. Details of these individual models are documented in 23 supporting Analysis/Model Reports (AMRs). Nineteen of these AMRs are for process models, and the remaining 4 describe the abstraction of results for application in TSPA. The process models themselves cluster around four major topics: ''Water Distribution and Removal Model, Physical and Chemical Environment Model, Radionuclide Transport Model, and Multiscale Thermohydrologic Model''. One AMR (Engineered Barrier System-Features, Events, and Processes/Degradation Modes Analysis) summarizes the formal screening analysis used to select the Features, Events, and Processes (FEPs) included in TSPA and those excluded from further consideration. Performance of a potential Yucca Mountain high-level radioactive waste repository depends on both the natural barrier system (NBS) and the engineered barrier system (EBS) and on their interactions. Although the waste packages are generally considered as components of the EBS, the EBS as defined in the EBS PMR includes all engineered components outside the waste packages. The principal function of the EBS is to complement the geologic system in limiting the amount of water contacting nuclear waste. A number of alternatives were considered by the Project for different EBS designs that could provide better performance than the design analyzed for the Viability Assessment. The design concept selected was Enhanced Design Alternative II (EDA II).

  18. Engineered Barrier System Degradation, Flow, and Transport Process Model Report

    International Nuclear Information System (INIS)

    The Engineered Barrier System Degradation, Flow, and Transport Process Model Report (EBS PMR) is one of nine PMRs supporting the Total System Performance Assessment (TSPA) being developed by the Yucca Mountain Project for the Site Recommendation Report (SRR). The EBS PMR summarizes the development and abstraction of models for processes that govern the evolution of conditions within the emplacement drifts of a potential high-level nuclear waste repository at Yucca Mountain, Nye County, Nevada. Details of these individual models are documented in 23 supporting Analysis/Model Reports (AMRs). Nineteen of these AMRs are for process models, and the remaining 4 describe the abstraction of results for application in TSPA. The process models themselves cluster around four major topics: ''Water Distribution and Removal Model, Physical and Chemical Environment Model, Radionuclide Transport Model, and Multiscale Thermohydrologic Model''. One AMR (Engineered Barrier System-Features, Events, and Processes/Degradation Modes Analysis) summarizes the formal screening analysis used to select the Features, Events, and Processes (FEPs) included in TSPA and those excluded from further consideration. Performance of a potential Yucca Mountain high-level radioactive waste repository depends on both the natural barrier system (NBS) and the engineered barrier system (EBS) and on their interactions. Although the waste packages are generally considered as components of the EBS, the EBS as defined in the EBS PMR includes all engineered components outside the waste packages. The principal function of the EBS is to complement the geologic system in limiting the amount of water contacting nuclear waste. A number of alternatives were considered by the Project for different EBS designs that could provide better performance than the design analyzed for the Viability Assessment. The design concept selected was Enhanced Design Alternative II (EDA II)

  19. Ultrasonic wave transducer for high temperature barrier

    International Nuclear Information System (INIS)

    This transducer is made by a metallic body pivoting on a support fixed to the barrier and an internal vitroceramic waveguide in contact on the barrier and on the other end on a piezoelectric ceramic element

  20. Prototype Hanford Surface Barrier: Design basis document

    International Nuclear Information System (INIS)

    The Hanford Site Surface Barrier Development Program (BDP) was organized in 1985 to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site and other arid sites. This document provides the basis of the prototype barrier. Engineers and scientists have momentarily frozen evolving barrier designs and incorporated the latest findings from BDP tasks. The design and construction of the prototype barrier has required that all of the various components of the barrier be brought together into an integrated system. This integration is particularly important because some of the components of the protective barreir have been developed independently of other barreir components. This document serves as the baseline by which future modifications or other barrier designs can be compared. Also, this document contains the minutes of meeting convened during the definitive design process in which critical decisions affecting the prototype barrier's design were made and the construction drawings

  1. Overcoming Barriers to Shared Decision Making

    Science.gov (United States)

    ... team to break it down. Barriers to shared decision making and solutions to overcome them include: Barrier: Fear, anger, stress or other emotions Solution: Strong emotions can interfere with your ability ...

  2. Market barriers to welfare product innovations

    OpenAIRE

    Binnekamp, M.H.A.; Ingenbleek, P. T. M.

    2006-01-01

    New products that are based on higher animal welfare standards encounter several barriers on the road to market acceptance. The authors focus on the Dutch poultry sector and distinguish between retailer and consumer barriers. Retailer barriers include the powerful position of retailers, the price competition, and the price-orientation of decision-makers. At the consumer level, potential barriers are: involving the consumer in animal welfare, making him understand the welfare benefits, convinc...

  3. NON-TARIFF TRADE BARRIERS IN AGRICULTURE

    OpenAIRE

    Mattson, Jeremy W.; Koo, Won W.; Taylor, Richard D.

    2004-01-01

    As trade agreements lower tariff rates throughout the world, other barriers to trade emerge. These non-tariff barriers can be just as troublesome for exporting companies. Non-tariff barriers include technical measures, customs rules and procedures, transport regulations or costs, lack of knowledge of regional markets, and import policies. The objective of this study is to identify non-tariff barriers faced by U.S., and more specifically North Dakota, exporting businesses, especially those inv...

  4. Alternative fuels for vehicles; Alternative drivmidler

    Energy Technology Data Exchange (ETDEWEB)

    2012-02-15

    Up until 2020 and onwards the analysis indicates that especially electricity, biogas and natural gas as propellants is economically attractive compared to conventional gasoline and diesel while other fuels have the same or higher costs for petrol and diesel. Especially biogas and electricity will also offer significant reductions in CO{sub 2} emissions, but also hydrogen, methanol, DME and to a lesser extent the second generation bioethanol and most of the other alternative fuels reduce CO{sub 2} emissions. Use of the traditional food-based first generation biofuels involves, at best, only modest climate benefits if land use changes are counted, and at worst, significant negative climate effects. Natural gas as a propellant involves a moderate climate gain, but may play a role for building infrastructure and market for gaseous fuels in large fleets, thereby contributing to the phasing in of biogas for transport. The electric-based automotive fuels are the most effective due to a high efficiency of the engine and an increasing proportion of wind energy in the electricity supply. The methanol track also has a relatively high efficiency. Among the others, the track based on diesel engines (biodiesel) is more effective than the track based on gasoline/Otto engines (gas and ethanol) as a result of the diesel engine's better efficiency. For the heavy vehicles all the selected alternative fuels to varying degrees reduce emissions of CO{sub 2}, particularly DME based on wood. The only exception to this is - as for passenger cars - the propellant synthetic diesel based on coal. (LN).

  5. Frozen Soil Barrier. Subsurface Contaminants Focus Area. OST Reference No. 51

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1999-09-01

    Problem: Hazardous and radioactive materials have historically been disposed of at the surface during operations at Department of Energy facilities. These contaminants have entered the subsurface, contaminating soils and groundwater resources. Remediation of these groundwater plumes using the baseline technology of pump and treat is expensive and takes a long time to complete. Containment of these groundwater plumes can be alternative or an addition to the remediation activities. Standard containment technologies include slurry walls, sheet piling, and grouting. These are permanent structures that once installed are difficult to remove. How It Works: Frozen Soil Barrier technology provides a containment alternative, with the key difference being that the barrier can be easily removed after a period of time, such as after the remediation or removal of the source is completed. Frozen Soil Barrier technology can be used to isolate and control the migration of underground radioactive or other hazardous contaminants subject to transport by groundwater flow. Frozen Soil Barrier technology consists of a series of subsurface heat transfer devices, known as thermoprobes, which are installed around a contaminant source and function to freeze the soil pore water. The barrier can easily be maintained in place until remediation or removal of the contaminants is complete, at which time the barrier is allowed to thaw.

  6. Frozen Soil Barrier. Subsurface Contaminants Focus Area. OST Reference No. 51

    International Nuclear Information System (INIS)

    Problem: Hazardous and radioactive materials have historically been disposed of at the surface during operations at Department of Energy facilities. These contaminants have entered the subsurface, contaminating soils and groundwater resources. Remediation of these groundwater plumes using the baseline technology of pump and treat is expensive and takes a long time to complete. Containment of these groundwater plumes can be alternative or an addition to the remediation activities. Standard containment technologies include slurry walls, sheet piling, and grouting. These are permanent structures that once installed are difficult to remove. How It Works: Frozen Soil Barrier technology provides a containment alternative, with the key difference being that the barrier can be easily removed after a period of time, such as after the remediation or removal of the source is completed. Frozen Soil Barrier technology can be used to isolate and control the migration of underground radioactive or other hazardous contaminants subject to transport by groundwater flow. Frozen Soil Barrier technology consists of a series of subsurface heat transfer devices, known as thermoprobes, which are installed around a contaminant source and function to freeze the soil pore water. The barrier can easily be maintained in place until remediation or removal of the contaminants is complete, at which time the barrier is allowed to thaw.

  7. Security barriers with automated reconnaissance

    Science.gov (United States)

    McLaughlin, James O; Baird, Adam D; Tullis, Barclay J; Nolte, Roger Allen

    2015-04-07

    An intrusion delaying barrier includes primary and secondary physical structures and can be instrumented with multiple sensors incorporated into an electronic monitoring and alarm system. Such an instrumented intrusion delaying barrier may be used as a perimeter intrusion defense and assessment system (PIDAS). Problems with not providing effective delay to breaches by intentional intruders and/or terrorists who would otherwise evade detection are solved by attaching the secondary structures to the primary structure, and attaching at least some of the sensors to the secondary structures. By having multiple sensors of various types physically interconnected serves to enable sensors on different parts of the overall structure to respond to common disturbances and thereby provide effective corroboration that a disturbance is not merely a nuisance or false alarm. Use of a machine learning network such as a neural network exploits such corroboration.

  8. Penetration through the Skin Barrier

    DEFF Research Database (Denmark)

    Nielsen, Jesper Bo; Benfeldt, Eva; Holmgaard, Rikke

    2016-01-01

    . During recent decades, the latter has received increased attention as a route for intentionally delivering drugs to patients. This has stimulated research in methods for sampling, measuring and predicting percutaneous penetration. Previous chapters have described how different endogenous, genetic and...... exogenous factors may affect barrier characteristics. The present chapter introduces the theory for barrier penetration (Fick's law), and describes and discusses different methods for measuring the kinetics of percutaneous penetration of chemicals, including in vitro methods (static and flow......-through diffusion cells) as well as in vivo methods (microdialysis and microperfusion). Then follows a discussion with examples of how different characteristics of the skin (age, site and integrity) and of the penetrants (size, solubility, ionization, logPow and vehicles) affect the kinetics of percutaneous...

  9. Perceptions regarding strategic and structural entry barriers

    NARCIS (Netherlands)

    Lutz, Clemens H. M.; Kemp, Ron G. M.; Dijkstra, S. Gerhard

    2010-01-01

    This article uses factor analysis to identify the underlying dimensions of strategic and structural entry barriers. We find that, in the perception of firms, both types of barriers are important and that the effectiveness of strategic barriers depends on attributes of the market structure. Based on

  10. Barriers to Mammography among Inadequately Screened Women

    Science.gov (United States)

    Stoll, Carolyn R. T.; Roberts, Summer; Cheng, Meng-Ru; Crayton, Eloise V.; Jackson, Sherrill; Politi, Mary C.

    2015-01-01

    Mammography use has increased over the past 20 years, yet more than 30% of women remain inadequately screened. Structural barriers can deter individuals from screening, however, cognitive, emotional, and communication barriers may also prevent mammography use. This study sought to identify the impact of number and type of barriers on mammography…

  11. Article Including Environmental Barrier Coating System

    Science.gov (United States)

    Lee, Kang N. (Inventor)

    2015-01-01

    An enhanced environmental barrier coating for a silicon containing substrate. The enhanced barrier coating may include a bond coat doped with at least one of an alkali metal oxide and an alkali earth metal oxide. The enhanced barrier coating may include a composite mullite bond coat including BSAS and another distinct second phase oxide applied over said surface.

  12. Sea sand for reactive barriers

    International Nuclear Information System (INIS)

    Some phosphates have the property to suck in radioactive metals in solution, what it is taken in advance to make reactive barriers which are placed in the nuclear waste repositories. In an effort for contributing to the study of this type of materials, it has been obtained the zirconium silicate (ZrSiO4) and the alpha zirconium hydrogen phosphate (Zr(HPO4) 2H2O) starting from sea sand in an easy and economic way. (Author)

  13. Removing Barriers to Interdisciplinary Research

    CERN Document Server

    Jacobs, Naomi

    2010-01-01

    A significant amount of high-impact contemporary scientific research occurs where biology, computer science, engineering and chemistry converge. Although programmes have been put in place to support such work, the complex dynamics of interdisciplinarity are still poorly understood. In this paper we interrogate the nature of interdisciplinary research and how we might measure its "success", identify potential barriers to its implementation, and suggest possible mechanisms for removing these impediments.

  14. Overcome barriers to career success

    Energy Technology Data Exchange (ETDEWEB)

    Raudsepp, E.

    1983-04-01

    A test is given to determine if an engineer suffers from one of the three barriers to technical success: fear of success, fear of failure, or perfectionism. As in most such tests, the middle way is best. Successful engineers know that perfection cannot be attained, that they don't have time to worry about failure or success, and that by aiming and perservering in doing things well, success can be achieved.

  15. Alternatives evaluation of high activity radioactive wastes disposal

    International Nuclear Information System (INIS)

    Different alternatives considered in the world to be used as barriers to isolate the high level radioactive from the environment wastes produced during the electric energy generation of nuclear origin are presented. Engineering and geologic barriers, are analyzed, considering nuclear fuel cycles with or without plutonium recycling; to that purpose the consideration of elements such as durability and resistance of the various engineering, availability of the fabrication processes, associated radiological impact, geological media apt to be used as geological barrier. Finally, the scopes of the Feasibility Study and Engineering draft are presented for the construction of a repository for high-level radioactive wastes, for the Argentine Nuclear Program needs, which contemplates the construction of six nuclear power plants with a potential installed towards the year 2000 GW(e), with natural and/or lowly enriched uranium power plants and recycling of plutonium generated in the cycle. (Author)

  16. Verification of the integrity of barriers using gas diffusion

    International Nuclear Information System (INIS)

    In-situ barrier materials and designs are being developed for containment of high risk contamination as an alternative to immediate removal or remediation. The intent of these designs is to prevent the movement of contaminants in either the liquid or vapor phase by long-term containment, essentially buying time until the contaminant depletes naturally or a remediation can be implemented. The integrity of the resultant soil-binder mixture is typically assessed by a number of destructive laboratory tests (leaching, compressive strength, mechanical stability with respect to wetting and freeze-thaw cycles) which as a group are used to infer the likelihood of favorable long-term performance of the barrier. The need exists for a minimally intrusive yet quantifiable methods for assessment of a barrier's integrity after emplacement, and monitoring of the barrier's performance over its lifetime. Here, the authors evaluate non-destructive measurements of inert-gas diffusion (specifically, SF6) as an indicator of waste-form integrity. The goals of this project are to show that diffusivity can be measured in core samples of soil jet-grouted with Portland cement, validate the experimental method through measurements on samples, and to calculate aqueous diffusivities from a series of diffusion measurements. This study shows that it is practical to measure SF6 diffusion rates in the laboratory on samples of grout (Portland cement and soil) typical of what might be used in a barrier. Diffusion of SF6 through grout (Portland cement and soil) is at least an order of magnitude slower than through air. The use of this tracer should be sensitive to the presence of fractures, voids, or other discontinuities in the grout/soil structure. Field-scale measurements should be practical on time-scales of a few days

  17. Barrier RF stacking at Fermilab

    International Nuclear Information System (INIS)

    A key issue to upgrade the luminosity of the Tevatron Run2 program and to meet the neutrino requirement of the NuMI experiment at Fermilab is to increase the proton intensity on the target. This paper introduces a new scheme to double the number of protons FR-om the Main Injector (MI) to the pbar production target (Run2) and to the pion production target (NuMI). It is based on the fact that the MI momentum acceptance is about a factor of four larger than the momentum spread of the Booster beam. Two RF barriers--one fixed, another moving--are employed to confine the proton beam. The Booster beams are injected off-momentum into the MI and are continuously reflected and compressed by the two barriers. Calculations and simulations show that this scheme could work provided that the Booster beam momentum spread can be kept under control. Compared with slip stacking, a main advantage of this new method is small beam loading effect thanks to the low peak beam current. The RF barriers can be generated by an inductive device, which uses nanocrystal magnet alloy (Finemet) cores and fast high voltage MOSFET switches. This device has been designed and fabricated by a Fermilab-KEK-Caltech team. The first bench test was successful. Beam experiments are being planned

  18. Filamentary and diffuse barrier discharges

    International Nuclear Information System (INIS)

    Barrier discharges, sometimes also referred to as dielectric-barrier discharges or silent discharges, are characterized by the presence of at least one insulating layer in contact with the discharge between two planar or cylindrical electrodes connected to an ac power supply. The main advantage of this type of electrical discharge is, that non-equilibrium plasma conditions in atmospheric-pressure gases can be established in an economic and reliable way. This has led to a number of important applications including industrial ozone generation, surface modification of polymers, plasma chemical vapor deposition, excitation of CO2 lasers, excimer lamps and, most recently, large-area flat plasma display panels. Depending on the application, the width of the discharge gap can range from less than 0.1 mm to about 100 mm and the applied frequency from below line frequency to several gigahertz. Typical materials used for the insulating layer (dielectric barrier) are glass, quartz, ceramics but also thin enamel or polymer layers

  19. Catalysis for alternative energy generation

    CERN Document Server

    2012-01-01

    Summarizes recent problems in using catalysts in alternative energy generation and proposes novel solutions  Reconsiders the role of catalysis in alternative energy generation  Contributors include catalysis and alternative energy experts from across the globe

  20. Alternative Green Solvents Project

    Science.gov (United States)

    Maloney, Phillip R.

    2012-01-01

    Necessary for safe and proper functioning of equipment. Mainly halogenated solvents. Tetrachloride, Trichloroethylene (TCE), CFC-113. No longer used due to regulatory/safety concerns. Precision Cleaning at KSC: Small % of total parts. Used for liquid oxygen (LOX) systems. Dual solvent process. Vertrel MCA (decafluoropentane (DFP) and trons-dichloroethylene) HFE-7100. DFP has long term environmental concerns. Project Goals: a) Identify potential replacements. b) 22 wet chemical processes. c) 3 alternative processes. d) Develop test procedures. e) Contamination and cleaning. f) Analysis. g) Use results to recommend alternative processes. Conclusions: a) No alternative matched Vertrel in this study. b) No clear second place solvent. c) Hydrocarbons- easy; Fluorinated greases- difficult. d) Fluorinated component may be needed in replacement solvent. e) Process may need to make up for shortcoming of the solvent. f) Plasma and SCC02 warrant further testing.

  1. Alternatives for pseudofinite groups

    CERN Document Server

    Houcine, Abderezak Ould

    2012-01-01

    The famous Tits' alternative states that a linear group either contains a nonabelian free group or is soluble-by-(locally finite). We study in this paper similar alternatives in pseudofinite groups. We show for instance that an $\\aleph_{0}$-saturated pseudofinite group either contains a subsemigroup of rank $2$ or is nilpotent-by-(uniformly locally finite). We call a class of finite groups $G$ weakly of bounded rank if the radical $rad(G)$ has a bounded Pr\\"ufer rank and the index of the sockel of $G/rad(G)$ is bounded. We show that an $\\aleph_{0}$-saturated pseudo-(finite weakly of bounded rank) group either contains a nonabelian free group or is nilpotent-by-abelian-by-(uniformly locally finite). We also obtain some relations between this kind of alternatives and amenability.

  2. Performance and risk assessment of subsurface barriers for single-shell tank waste retrieval

    International Nuclear Information System (INIS)

    Subsurface barriers are among various alternatives under evaluation to mitigate the threat of leakage from the Hanford Site's 149 single-shell high-level radioactive waste tanks. The Tank Waste Remediation System (TWRS) division of Westinghouse Hanford Company is conducting this evaluation of subsurface barriers and other alternatives, focusing on risk and cost as performance measures. A number of alternative retrieval/closure approaches were evaluated in terms of risks (carcinogenic and toxicological) to a postulated maximally exposed individual. In addition, worker and accident risks were evaluated and factors developed for each alternative on a relative basis. The work performed to date indicates the use of subsurface barriers may potentially reduce public risk by limiting contamination of groundwater below the Hanford Site; however, the cost in terms of actual funding and in elevated worker risk is significant. The analyses also assume certain performance levels for technologies that have not been demonstrated in field conditions similar to Hanford Site tank farms. The evaluations summarized herein are being used to support a decision by representatives of the US Department of Energy, Richland Operations Office, the Washington State Department of Ecology (Ecology), and the US Environmental Protection Agency (EPA) regarding potential further development of subsurface barrier technology

  3. Stacking fault induced tunnel barrier in platelet graphite nanofiber

    Science.gov (United States)

    Lan, Yann-Wen; Chang, Wen-Hao; Li, Yuan-Yao; Chang, Yuan-Chih; Chang, Chia-Seng; Chen, Chii-Dong

    2014-09-01

    A correlation study using image inspection and electrical characterization of platelet graphite nanofiber devices is conducted. Close transmission electron microscopy and diffraction pattern inspection reveal layers with inflection angles appearing in otherwise perfectly stacked graphene platelets, separating nanofibers into two domains. Electrical measurement gives a stability diagram consisting of alternating small-large Coulomb blockade diamonds, suggesting that there are two charging islands coupled together through a tunnel junction. Based on these two findings, we propose that a stacking fault can behave as a tunnel barrier for conducting electrons and is responsible for the observed double-island single electron transistor characteristics.

  4. Stacking fault induced tunnel barrier in platelet graphite nanofiber

    International Nuclear Information System (INIS)

    A correlation study using image inspection and electrical characterization of platelet graphite nanofiber devices is conducted. Close transmission electron microscopy and diffraction pattern inspection reveal layers with inflection angles appearing in otherwise perfectly stacked graphene platelets, separating nanofibers into two domains. Electrical measurement gives a stability diagram consisting of alternating small-large Coulomb blockade diamonds, suggesting that there are two charging islands coupled together through a tunnel junction. Based on these two findings, we propose that a stacking fault can behave as a tunnel barrier for conducting electrons and is responsible for the observed double-island single electron transistor characteristics.

  5. Stacking fault induced tunnel barrier in platelet graphite nanofiber

    Energy Technology Data Exchange (ETDEWEB)

    Lan, Yann-Wen, E-mail: chiidong@phys.sinica.edu.tw, E-mail: ywlan@phys.sinica.edu.tw; Chang, Yuan-Chih; Chang, Chia-Seng; Chen, Chii-Dong, E-mail: chiidong@phys.sinica.edu.tw, E-mail: ywlan@phys.sinica.edu.tw [Institute of Physics, Academia Sinica, Taipei 115, Taiwan (China); Chang, Wen-Hao [Institute of Physics, Academia Sinica, Taipei 115, Taiwan (China); Graduate Institute of Opto-Mechatronics, National Chung Cheng University, Chia-Yi 62102, Taiwan (China); Li, Yuan-Yao [Graduate Institute of Opto-Mechatronics, National Chung Cheng University, Chia-Yi 62102, Taiwan (China)

    2014-09-08

    A correlation study using image inspection and electrical characterization of platelet graphite nanofiber devices is conducted. Close transmission electron microscopy and diffraction pattern inspection reveal layers with inflection angles appearing in otherwise perfectly stacked graphene platelets, separating nanofibers into two domains. Electrical measurement gives a stability diagram consisting of alternating small-large Coulomb blockade diamonds, suggesting that there are two charging islands coupled together through a tunnel junction. Based on these two findings, we propose that a stacking fault can behave as a tunnel barrier for conducting electrons and is responsible for the observed double-island single electron transistor characteristics.

  6. Phosphate Barriers for Immobilization of Uranium Plumes

    Energy Technology Data Exchange (ETDEWEB)

    Burns, Peter C.

    2004-12-01

    Uranium contamination of the subsurface remains a persistent problem plaguing remedial design at sites across the U.S. that were involved with production, handling, storage, milling, and reprocessing of uranium for both civilian and defense related purposes. Remediation efforts to date have relied upon excavation, pump-and-treat, or passive remediation barriers (PRB?s) to remove or attenuate uranium mobility. Documented cases convincingly demonstrate that excavation and pump-and-treat methods are ineffective for a number of highly contaminated sites. There is growing concern that use of conventional PRB?s, such as zero-valent iron, may be a temporary solution to a problem that will persist for thousands of years. Alternatives to the standard treatment methods are therefore warranted. The core objective of our research is to demonstrate that a phosphorus amendment strategy will result in a reduction of dissolved uranium to below the proposed drinking water standard. Our hypothesis is that long-chain sodium polyphosphate compounds forestall precipitation of sparingly soluble uranyl phosphate compounds, which is paramount to preventing fouling of wells at the point of injection.

  7. Phosphate Barriers for Immobilization of Uranium Plumes

    Energy Technology Data Exchange (ETDEWEB)

    Icenhower, Jonathan P.; Burns, Peter C.

    2005-06-01

    Uranium contamination of the subsurface remains a persistent problem plaguing remedial design at sites across the U.S. that were involved with production, handling, storage, milling, and reprocessing of uranium for both civilian and defense related purposes. Remediation efforts to date have relied upon excavation, pump-and-treat, or passive remediation barriers (PRB?s) to remove or attenuate uranium mobility. Documented cases convincingly demonstrate that excavation and pump-and-treat methods are ineffective for a number of highly contaminated sites. There is growing concern that use of conventional PRB's, such as zero-valent iron, may be a temporary solution to a problem that will persist for thousands of years. Alternatives to the standard treatment methods are therefore warranted. The core objective of our research is to demonstrate that a phosphorous amendment strategy will result in a reduction of dissolved uranium to below the proposed drinking water standard. Our hypothesis is that long-chain sodium polyphosphate compounds forestall precipitation of sparingly soluble uranyl phosphate compounds, which is paramount to preventing fouling of wells at the point of injection.

  8. Bouncing alternatives to inflation

    CERN Document Server

    Lilley, Marc

    2015-01-01

    Although the inflationary paradigm is the most widely accepted explanation for the current cosmological observations, it does not necessarily correspond to what actually happened in the early stages of our Universe. To decide on this issue, two paths can be followed: first, all the possible predictions it makes must be derived thoroughly and compared with available data, and second, all imaginable alternatives must be ruled out. Leaving the first task to all other contributors of this volume, we concentrate here on the second option, focusing on the bouncing alternatives and their consequences.

  9. Renewable and alternative energy

    CERN Document Server

    Curley, Robert

    2011-01-01

    With growing populations across the world consuming Earth's limited oil and natural gas reserves, the environmental and economic toll of energy dependence becomes an increasingly global concern. The development of renewable forms of energy-solar, wind, water, and geothermal, to name a few-offers alternatives to fossil fuels. Consumers are embracing these new modes of energy delivery and use. This extensive volume examines the possibility of a cleaner and more energy efficient future by detailing the historic and emerging technologies behind some the most promising alternative resources.

  10. Domestic energy alternatives

    International Nuclear Information System (INIS)

    These alternatives include biomass, clean coal, geothermal, hydropower, natural gas, nuclear, solar and photovoltaic, and wind. With the current, volatile situation in the Middle East, this nation's political leaders appear to be left scratching their heads in their attempts to come up with new, sound, energy policies to reduce our dependence on foreign oil. Therefore, the FORTNIGHTLY's editorial staff thought that this might be an opportune time to briefly examine some home-grown and environmentally responsible fuel alternatives to black gold. While some of these electricity-producing technologies are still on the horizon, others are available now

  11. Market and policy barriers to energy storage deployment : a study for the energy storage systems program.

    Energy Technology Data Exchange (ETDEWEB)

    Bhatnagar, Dhruv; Currier, Aileen B.; Hernandez, Jacquelynne; Ma, Ookie [U.S. Department of Energy, Washington, D.C.; Kirby, Brendan [U.S. Department of Energy, Washington, D.C.

    2013-09-01

    Electric energy storage technologies have recently been in the spotlight, discussed as essential grid assets that can provide services to increase the reliability and resiliency of the grid, including furthering the integration of variable renewable energy resources. Though they can provide numerous grid services, there are a number of factors that restrict their current deployment. The most significant barrier to deployment is high capital costs, though several recent deployments indicate that capital costs are decreasing and energy storage may be the preferred economic alternative in certain situations. However, a number of other market and regulatory barriers persist, limiting further deployment. These barriers can be categorized into regulatory barriers, market (economic) barriers, utility and developer business model barriers, crosscutting barriers and technology barriers. This report, through interviews with stakeholders and review of regulatory filings in four regions roughly representative of the United States, identifies the key barriers restricting further energy storage development in the country. The report also includes a discussion of possible solutions to address these barriers and a review of initiatives around the country at the federal, regional and state levels that are addressing some of these issues. Energy storage could have a key role to play in the future grid, but market and regulatory issues have to be addressed to allow storage resources open market access and compensation for the services they are capable of providing. Progress has been made in this effort, but much remains to be done and will require continued engagement from regulators, policy makers, market operators, utilities, developers and manufacturers.

  12. Development of microfluidic cell culture devices towards an in vitro human intestinal barrier model

    DEFF Research Database (Denmark)

    Tan, Hsih-Yin

    displaying folds that closely resembled the intestinal villi and formation of a tight barrier. Furthermore, the microelectrodes embedded in the microchip also allow real-time monitoring of the barrier integrity by means of measuring the trans-epithelial electrical resistance. Demonstrations of transport...... enable real-time detection of cell responses, adjustment of cellular stimulation etc. leading to establishment of conditional experiments. In this project, microfluidic systems engineering was leveraged to develop an eight chamber multi-layer microchip for intestinal barrier studies. Sandwiched between...... without compromising the epithelial cell viability and barrier function. Such a platform paves the way towards an alternative in vitro intestinal model for high throughput screening of drugs, chemicals, pathogens, intestinal diseases as well as toxicological studies....

  13. Electric Field Control of the Resistance of Multiferroic Tunnel Junctions with Magnetoelectric Antiferromagnetic Barriers

    Science.gov (United States)

    Merodio, P.; Kalitsov, A.; Chshiev, M.; Velev, J.

    2016-06-01

    Based on model calculations, we predict a magnetoelectric tunneling electroresistance effect in multiferroic tunnel junctions consisting of ferromagnetic electrodes and magnetoelectric antiferromagnetic barriers. Switching of the antiferromagnetic order parameter in the barrier in applied electric field by means of the magnetoelectric coupling leads to a substantial change of the resistance of the junction. The effect is explained in terms of the switching of the orientations of local magnetizations at the barrier interfaces affecting the spin-dependent interface transmission probabilities. Magnetoelectric multiferroic materials with finite ferroelectric polarization exhibit an enhanced resistive change due to polarization-induced spin-dependent screening. These results suggest that devices with active barriers based on single-phase magnetoelectric antiferromagnets represent an alternative nonvolatile memory concept.

  14. Experimental investigation of terahertz quantum cascade laser with variable barrier heights

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Aiting; Vijayraghavan, Karun; Belkin, Mikhail A., E-mail: mbelkin@ece.utexas.edu [Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78758 (United States); Matyas, Alpar; Jirauschek, Christian [Institute for Nanoelectronics, Technische Universität München, D-80333 Munich (Germany); Wasilewski, Zbig R. [Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G (Canada)

    2014-04-28

    We report an experimental study of terahertz quantum cascade lasers with variable barrier heights based on the Al{sub x}Ga{sub 1–x}As/GaAs material system. Two new designs are developed based on semiclassical ensemble Monte Carlo simulations using state-of-the-art Al{sub 0.15}Ga{sub 0.85}As/GaAs three-quantum-well resonant phonon depopulation active region design as a reference. The new designs achieved maximum lasing temperatures of 188 K and 172 K, as compared to the maximum lasing temperature of 191 K for the reference structure. These results demonstrate that terahertz quantum cascade laser designs with variable barrier heights provide a viable alternative to the traditional active region designs with fixed barrier composition. Additional design space offered by using variable barriers may lead to future improvements in the terahertz quantum cascade laser performance.

  15. Experimental investigation of terahertz quantum cascade laser with variable barrier heights

    International Nuclear Information System (INIS)

    We report an experimental study of terahertz quantum cascade lasers with variable barrier heights based on the AlxGa1–xAs/GaAs material system. Two new designs are developed based on semiclassical ensemble Monte Carlo simulations using state-of-the-art Al0.15Ga0.85As/GaAs three-quantum-well resonant phonon depopulation active region design as a reference. The new designs achieved maximum lasing temperatures of 188 K and 172 K, as compared to the maximum lasing temperature of 191 K for the reference structure. These results demonstrate that terahertz quantum cascade laser designs with variable barrier heights provide a viable alternative to the traditional active region designs with fixed barrier composition. Additional design space offered by using variable barriers may lead to future improvements in the terahertz quantum cascade laser performance

  16. Cryogenic Barrier Demonstration Project. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L.A.; Yarmak, E.; Long, E.L.

    2000-03-01

    A long-term frozen soil barrier was implemented at the HRE (Homogeneous Reactor Experiment) Pond facility at the Oak Ridge National Laboratory in 1997. This was performed to verify the technical feasibility and costs of deploying a frozen barrier at a radiologically contaminated site. Work began in September 1996 and progressed through to December 1999. The frozen barrier has been operational since November 1997. Verification of the barrier integrity was performed independently by the EPA's SITE Program. This project showed frozen barriers offer a proven technology to retain below grade hazardous substances at relatively low costs with minimal effect on the environment.

  17. The influence of different types of barrier creams on skin barrier function / Sonette du Plessis

    OpenAIRE

    Du Plessis, Sonette

    2012-01-01

    Aims and objectives: The research aims and objectives of this study were: Firstly to determine the positive effects and possible disadvantages of three types of barrier creams on skin barrier function by determining skin barrier function by measuring stratum corneum hydration transepidermal water loss (TEWL) and skin surface pH. Secondly to compare different racial skin types (African skin to Caucasian skin) by determining the effects of barrier cream on skin barrier function. Finally to comp...

  18. Barriers to health care for undocumented immigrants: a literature review

    Directory of Open Access Journals (Sweden)

    Hacker K

    2015-10-01

    Full Text Available Karen Hacker,1,2 Maria Anies,2 Barbara L Folb,2,3 Leah Zallman4–6 1Allegheny County Health Department, Pittsburgh, PA, USA; 2Graduate School of Public Health, 3Health Sciences Library System, University of Pittsburgh, Pittsburgh, PA, USA; 4Institute for Community Health, Cambridge, MA, USA; 5Cambridge Health Alliance, Cambridge, MA, USA; 6Harvard School of Medicine, Boston, MA, USA Abstract: With the unprecedented international migration seen in recent years, policies that limit health care access have become prevalent. Barriers to health care for undocumented immigrants go beyond policy and range from financial limitations, to discrimination and fear of deportation. This paper is aimed at reviewing the literature on barriers to health care for undocumented immigrants and identifying strategies that have or could be used to address these barriers. To address study questions, we conducted a literature review of published articles from the last 10 years in PubMed using three main concepts: immigrants, undocumented, and access to health care. The search yielded 341 articles of which 66 met study criteria. With regard to barriers, we identified barriers in the policy arena focused on issues related to law and policy including limitations to access and type of health care. These varied widely across countries but ultimately impacted the type and amount of health care any undocumented immigrant could receive. Within the health system, barriers included bureaucratic obstacles including paperwork and registration systems. The alternative care available (safety net was generally limited and overwhelmed. Finally, there was evidence of widespread discriminatory practices within the health care system itself. The individual level focused on the immigrant’s fear of deportation, stigma, and lack of capital (both social and financial to obtain services. Recommendations identified in the papers reviewed included advocating for policy change to increase

  19. Avoiding barriers in control of mowing robot

    Institute of Scientific and Technical Information of China (English)

    QIU Bai-jing; QIAN Guo-hong; XIANG Zhong-ping; LI Zuo-peng

    2006-01-01

    Due to complicated barriers,it is difficult to track the path of the mowing robot and to avoid barriers.In order to solve the problem,a method based on distance-measuring sensors and fuzzy control inputs was proposed.Its track was composed of beelines and was easy to tail.The fuzzy control inputs were based on the front barrier distance and the difference between the left and right barrier distance measured by ultrasonic sensors;the output was the direction angle.The infrared sensors around the robot improved its safety in avoiding barriers.The result of the method was feasible,agile,and stable.The distance between the robot and the barriers could be changed by altering the inputs and outputs of fuzzy control and the length of the beelines.The disposed sensors can fulfill the need of the robot in avoiding barriers.

  20. Dielectric barrier discharges in analytical chemistry.

    Science.gov (United States)

    Meyer, C; Müller, S; Gurevich, E L; Franzke, J

    2011-06-21

    The present review reflects the importance of dielectric barrier discharges in analytical chemistry. Special about this discharge is-and in contrast to usual discharges with direct current-that the plasma is separated from one or two electrodes by a dielectric barrier. This gives rise to two main features of the dielectric barrier discharges; it can serve as dissociation and excitation device and as ionization mechanism, respectively. The article portrays the various application fields for dielectric barrier discharges in analytical chemistry, for example the use for elemental detection with optical spectrometry or as ionization source for mass spectrometry. Besides the introduction of different kinds of dielectric barrier discharges used for analytical chemistry from the literature, a clear and concise classification of dielectric barrier discharges into capacitively coupled discharges is provided followed by an overview about the characteristics of a dielectric barrier discharge concerning discharge properties and the ignition mechanism. PMID:21562672

  1. Compensated pulsed alternator

    International Nuclear Information System (INIS)

    This invention relates to an electromechanical energy converter with inertial energy storage. The device, a single phase, two or multi-pole alternator with stationary field coils, and a rotating armature is provided. The rotor itself may be of laminated steel for slower pulses or for faster pulses should be nonmagnetic and electrically nonconductive in order to allow rapid penetration of the field as the armature coil rotates. The armature coil comprises a plurality of power generating conductors mounted on the rotor. The alternator may also include a stationary or counterrotating compensating coil to increase the output voltage thereof and to reduce the internal impedance of the alternator at the moment of peak output. As the machine voltage rises sinusoidally, an external trigger switch is adapted to be closed at the appropriate time to create the desired output current from said alternator to an external load circuit, and as the output current passes through zero a self-commutating effect is provided to allow the switch to disconnect the generator from the external circuit

  2. Alternatives to Violence.

    Science.gov (United States)

    Children Today, 1994

    1994-01-01

    Notes that our capacity to diffuse conflict rests in our ability to recognize and verbalize feelings, develop empathy, and think of alternatives to violence. Explores the influence of role models and culture on violence and how the media can use violent images effectively in helping us confront a culture of violence. (HTH)

  3. Tracking alternative energy sources

    International Nuclear Information System (INIS)

    This is the third and last article dealing with global energy topics analyzed at the 13th World Energy Congress. The varied particality or applicability of the following alternative energy sources is briefly discussed at a popular level: fusion, solar, ocean thermal energy conversion, waves, winds, tidal, and geothermal

  4. Alternatives to Blood Transfusion

    Science.gov (United States)

    ... saved articles window. My Saved Articles » My ACS » Blood Transfusion and Donation + - Text Size Download Printable Version [PDF] » TOPICS Document ... Possible risks of blood transfusions Alternatives to blood transfusions Donating blood Blood donation by cancer survivors To learn more References Previous ...

  5. Alternative health insurance schemes

    DEFF Research Database (Denmark)

    Keiding, Hans; Hansen, Bodil O.

    2002-01-01

    In this paper, we present a simple model of health insurance with asymmetric information, where we compare two alternative ways of organizing the insurance market. Either as a competitive insurance market, where some risks remain uninsured, or as a compulsory scheme, where however, the level...

  6. TWTF design alternates

    International Nuclear Information System (INIS)

    The Transuranic Waste Treatment Facility (TWTF) will process transuranic (TRU) waste in retrievable storage at the Idaho National Engineering Laboratory (INEL). The costs for a TWTF concept using a slagging pyrolysis incinerator were excessive. Alternate concepts using a slow speed shredder, a rotary kiln incinerator, and concrete immobilization should result in significant cost reductions. These will be included in future TWTF considerations

  7. Alternative and Integrative Medicine

    Science.gov (United States)

    ... are the healthcare rituals practiced by a given culture (eg, Asian, Indian, African). Homeopathic Medicine: This alternative medicine system is based on the principle that “like cures like.” In other words, the same substance ... American Brain Tumor Association 8550 W. Bryn Mawr Ave. ...

  8. Double barrier system for an in situ conversion process

    Science.gov (United States)

    McKinzie, Billy John [Houston, TX; Vinegar, Harold J [Bellaire, TX; Cowan, Kenneth Michael [Sugar land, TX; Deeg, Wolfgang Friedrich Johann [Houston, TX; Wong, Sau-Wai [Rijswijk, NL

    2009-05-05

    A barrier system for a subsurface treatment area is described. The barrier system includes a first barrier formed around at least a portion of the subsurface treatment area. The first barrier is configured to inhibit fluid from exiting or entering the subsurface treatment area. A second barrier is formed around at least a portion of the first barrier. A separation space exists between the first barrier and the second barrier.

  9. Tunneling without barriers with gravity

    OpenAIRE

    Kanno, Sugumi; Sasaki, Misao; Soda, Jiro

    2012-01-01

    We consider the vacuum decay of the flat Minkowski space to an anti-de Sitter space. We find a one-parameter family of potentials that allow exact, analytical instanton solutions describing tunneling without barriers in the presence of gravity. In the absence of gravity such instantons were found and discussed by Lee and Weinberg more than a quarter of a century ago. The bounce action is also analytically computed. We discuss possible implications of these new instantons to cosmology in the c...

  10. Overcoming cultural barriers to change.

    Science.gov (United States)

    Hill, S; McNulty, D

    1998-01-01

    This article is a case study which focuses on organisational and cultural change associated with the incorporation of a college which provided pre- and post-registration nursing and midwifery education into a much larger institution within the university sector. Among the issues addressed is whether transformational change, such as that represented by incorporation or merger, can be used by managers to successfully refashion the culture of the organisation, making more effective than traditional or discipline-based management structures. It examines the barriers to change and the various considerations that arose in determining the fit of managerial styles and assesses the outcomes of the process of change. PMID:10346302

  11. Overcoming barriers to wind project finance in Australia

    International Nuclear Information System (INIS)

    The wind power industry in Australia is expected to grow rapidly over the next decade, primarily due to a forthcoming expanded national renewable energy target (RET) which will mandate that renewable sources provide approximately 20% of Australia's electricity production by 2020. However, development of new wind generation in Australia has stalled as a result of several barriers to project finance, the mechanism through which most wind farms have been developed historically. This paper provides an overview of wind power financing in Australia in light of recent political and financial trends. Drawing upon existing literature and a series of stakeholder interviews, it identifies three primary barriers to project finance: regulatory risk surrounding legislation of the RET, semi-privatization of electricity retailers in New South Wales, and limited capital availability resulting from the recent global credit crisis. The paper concludes that the confluence of these barriers limits the availability of long-term contracts that provide revenue certainty for pre-construction wind projects, while simultaneously making these contracts a necessity in order to obtain project finance. In an attempt to mitigate these effects, this paper identifies four alternative development strategies that can be pursued.

  12. [Alternatives to animal testing].

    Science.gov (United States)

    Fabre, Isabelle

    2009-11-01

    The use of alternative methods to animal testing are an integral part of the 3Rs concept (refine, reduce, replace) defined by Russel & Burch in 1959. These approaches include in silico methods (databases and computer models), in vitro physicochemical analysis, biological methods using bacteria or isolated cells, reconstructed enzyme systems, and reconstructed tissues. Emerging "omic" methods used in integrated approaches further help to reduce animal use, while stem cells offer promising approaches to toxicologic and pathophysiologic studies, along with organotypic cultures and bio-artificial organs. Only a few alternative methods can so far be used in stand-alone tests as substitutes for animal testing. The best way to use these methods is to integrate them in tiered testing strategies (ITS), in which animals are only used as a last resort. PMID:20669543

  13. Outlook for alternative transportation fuels

    Energy Technology Data Exchange (ETDEWEB)

    Gushee, D.E. [Univ. of Illinois, Chicago, IL (United States)

    1996-12-31

    This presentation provides a brief review of regulatory issues and Federal programs regarding alternative fuel use in automobiles. A number of U.S. DOE initiatives and studies aimed at increasing alternative fuels are outlined, and tax incentives in effect at the state and Federal levels are discussed. Data on alternative fuel consumption and alternative fuel vehicle use are also presented. Despite mandates, tax incentives, and programs, it is concluded alternative fuels will have minimal market penetration. 7 refs., 5 tabs.

  14. ALTERNATIVE DISPUTE RESOLUTION

    Directory of Open Access Journals (Sweden)

    Mihaela Irina IONESCU

    2015-12-01

    Full Text Available Alternative dispute resolution (ADR includes dispute resolution processes and techniques that act as a means for disagreeing parties to come to an agreement short of litigation. It is a collective term for the ways that parties can settle disputes, with (or without the help of a third party.Despite historic resistance to ADR by many popular parties and their advocates, ADR has gained widespread acceptance among both the general public and the legal profession in recent years. In fact, some courts now require some parties to resort to ADR of some type, before permitting the parties' cases to be tried. The rising popularity of ADR can be explained by the increasing caseload of traditional courts, the perception that ADR imposes fewer costs than litigation, a preference for confidentiality, and the desire of some parties to have greater control over the selection of the individual or individuals who will decide their dispute.Directive 2013/11/EU of the European Parliament and of the Council on alternative dispute resolution for consumer disputes and amending Regulation (EC No 2006/2004 and Directive 2009/22/EC (hereinafter „Directive 2013/11/EU” aims to ensure a high level of consumer protection and the proper functioning of the internal market by ensuring that complaints against traders can be submitted by consumers on a voluntary basis, to entities of alternative disputes which are independent, impartial, transparent, effective, simple,quick and fair.Directive 2013/11/EU establishes harmonized quality requirements for entities applying alternative dispute resolution procedure (hereinafter "ADR entity" to provide the same protection and the same rights of consumers in all Member States.Besides this, the present study is trying to present broadly how are all this trasposed in the romanian legislation.

  15. Alternatives to ECMO.

    OpenAIRE

    Donn, S M

    1994-01-01

    The past decade has witnessed technological advancements which are unparalleled in neonatology. ECMO has been demonstrated to be a powerful rescue treatment, but has perhaps been overutilised and is not universally available. Alternative treatments have been shown to be both safe and efficacious in the management of infants with respiratory failure. Direct head to head clinical trials will probably be necessary to establish appropriate criteria and indications for use, given the wide diversit...

  16. Alternative approaches in IVF

    OpenAIRE

    Fauser, Bart; Bouchard, P.; Coelingh Bennink, H.J.; Collins, John; Devroey, P.; Evers, Johannes; Van Steirteghem, A

    2002-01-01

    textabstractVarious new developments in clinical and basic science which may impact on IVF in the near or distant future will be discussed in this review. These key areas include the regulation of early follicle development and the extended in-vitro culture of oocytes and embryos. Moreover, alternative compounds and ovarian stimulation protocols will be discussed, along with highlights in the development of the cryopreservation of excess oocytes or embryos. Finally, the health economics of IV...

  17. Alternative Dispute Resolution

    OpenAIRE

    Mihaela Irina IONESCU

    2004-01-01

    Alternative dispute resolution (ADR) includes dispute resolution processes and techniques that act as a means for disagreeing parties to come to an agreement short of litigation. It is a collective term for the ways that parties can settle disputes, with (or without) the help of a third party.Despite historic resistance to ADR by many popular parties and their advocates, ADR has gained widespread acceptance among both the general public and the legal profession in recent years. In fact, some ...

  18. Metamaterials critique and alternatives

    CERN Document Server

    Munk, Ben A

    2009-01-01

    A Convincing and Controversial Alternative Explanation of Metamaterials with a Negative Index of Refraction In a book that will generate both support and controversy, one of the world's foremost authorities on periodic structures addresses several of the current fashions in antenna design-most specifically, the popular subject of double negative metamaterials. Professor Munk provides a comprehensive theoretical electromagnetic investigation of the issues and concludes that many of the phenomena claimed by researchers may be impossible. While denying the existence of negative refractio

  19. Alternatives to Higgs scalars

    International Nuclear Information System (INIS)

    We discuss alternatives to the Higgs Scalar doublet Φ of the minimal standard model. In particular we review technicolor (TC) and extended technicolor (ETC), and show that the threat of flavour changing neutral currents (FCNC's) is avoided by walking TC and/or strongly coupled ETC. The phenomenology of minimal TC and the techni-family is discussed. Finally we consider the possibility that the Higgs doublet Φ is a composite bound state of quarks from the third (or fourth) family

  20. Fixed field alternating gradient

    OpenAIRE

    Machida, Shinji

    2013-01-01

    The concept of a fixed field alternating gradient (FFAG) accelerator was invented in the 1950s. Although many studies were carried out up to the late 1960s, there has been relatively little progress until recently, when it received widespread attention as a type of accelerator suitable for very fast acceleration and for generating high-power beams. In this paper, we describe the principles and design procedure of a FFAG accelerator.

  1. State of offsite construction in India-Drivers and barriers

    Science.gov (United States)

    Arif, M.; Bendi, D.; Sawhney, A.; Iyer, K. C.

    2012-05-01

    The rapid growth of the construction industry in India has influenced key players in the industry to adopt alternative technologies addressing time, cost and quality. The rising demand in housing, infrastructure and other facilities have further highlighted the need for the construction industry to look at adopting alternate building technologies. Offsite construction has evolved as a panacea to dealing with the under-supply and poor quality in the current age construction industry. Several offsite techniques have been adopted by the construction sector. Although, different forms of offsite techniques have been around for a while but their uptake has been low in the Indian context. This paper presents the perceptions about offsite construction in India and highlights some of the barriers and drivers facing the Indian construction industry. The data was gathered through a survey of 17 high level managers from some of the largest stakeholder organizations of the construction sector in India. The influence of time and cost has been highlighted as a major factor fuelling the adoption of offsite construction. However, the influence of current planning systems and the need for a paradigm shift are some of the prominent barriers towards the adoption of offsite techniques.

  2. Saving the Barrier by Prevention.

    Science.gov (United States)

    Weisshaar, Elke

    2016-01-01

    One third of all occupation-related diseases are diseases of the skin, and in most of these cases the skin barrier is involved. Professions such as metalworkers, hairdressers, and health care and construction workers are mainly affected. Among them, contact dermatitis is the leading skin disease. It usually presents as hand eczema caused by or leading to impaired barrier function. All this significantly impacts the function of the hands, reduces the ability to work and especially impairs the patient's quality of life. Diagnostics and therapy are of great importance; in addition, prevention programs are meanwhile an important mainstay of the overall therapeutic concept. They comprise measures of secondary (outpatient) and tertiary (inpatient) prevention. Secondary prevention measures include occupation-tailored teaching and prevention programs, and the dermatologist's examination and report. In severe cases or if therapy is not successful in the long term, or if the diagnosis is not clear, measures of tertiary prevention may come into action. They are offered as an inpatient treatment and prevention program. The aims are prevention of the job loss, but especially to reach a long-term healing up and getting back to normal occupational and leisure life in the sense of attaining full quality of life. During the last years, research in Germany has shown that the different measures of prevention in occupational dermatology are very effective. This integrated concept of an in-/outpatient disease management reveals remarkable pertinent efficacy for patients with severe occupational dermatoses in at-risk professions. PMID:26844907

  3. Triggering mechanisms for transport barriers

    International Nuclear Information System (INIS)

    The radial shear ωExB of the ExB flow is evaluated with the Monte Carlo orbit following code ASCOT at the onset of the L-H transition and internal transport barriers (ITB) in JET, TFTR, ASDEX Upgrade, TEXTOR, and FT-2 tokamaks. Systematically, a large shear (sufficient for turbulence suppression) is found for local parameters close to the experimental threshold conditions at the barrier location. For L-H transition in JET and ASDEX Upgrade, the large shear is obtained by increasing the edge ion temperature. For TEXTOR, the radial electric field and the electrode current bifurcate at a threshold electrode voltage. In a JET database study, toroidal rotation is found to be dominant in triggering the JET ITB, and an empirical s-ωExB fit is found for the transition threshold. For TFTR and FT-2, in which toroidal rotation does not play a role, ASCOT predicts a significant ωExB shear for the ITB conditions. The ripple-induced transport is not found to be important here. (author)

  4. Barriers to medical error reporting

    Directory of Open Access Journals (Sweden)

    Jalal Poorolajal

    2015-01-01

    Full Text Available Background: This study was conducted to explore the prevalence of medical error underreporting and associated barriers. Methods: This cross-sectional study was performed from September to December 2012. Five hospitals, affiliated with Hamadan University of Medical Sciences, in Hamedan,Iran were investigated. A self-administered questionnaire was used for data collection. Participants consisted of physicians, nurses, midwives, residents, interns, and staffs of radiology and laboratory departments. Results: Overall, 50.26% of subjects had committed but not reported medical errors. The main reasons mentioned for underreporting were lack of effective medical error reporting system (60.0%, lack of proper reporting form (51.8%, lack of peer supporting a person who has committed an error (56.0%, and lack of personal attention to the importance of medical errors (62.9%. The rate of committing medical errors was higher in men (71.4%, age of 50-40 years (67.6%, less-experienced personnel (58.7%, educational level of MSc (87.5%, and staff of radiology department (88.9%. Conclusions: This study outlined the main barriers to reporting medical errors and associated factors that may be helpful for healthcare organizations in improving medical error reporting as an essential component for patient safety enhancement.

  5. Westinghouse thermal barrier coatings development

    Energy Technology Data Exchange (ETDEWEB)

    Goedjen, J.G.; Wagner, G. [Westinghouse Electric Corp., Orlando, FL (United States)

    1995-10-01

    Westinghouse, in conjunction with the Department of Energy and Oak Ridge National Laboratory, has embarked upon a program for the development of advanced thermal barrier coatings for industrial gas turbines. Development of thermal barrier coatings (TBC`s) for industrial gas turbines has relied heavily on the transfer of technology from the aerospace industry. Significant differences in the time/temperature/stress duty cycles exist between these two coating applications. Coating systems which perform well in aerospace applications may not been optimized to meet power generation performance requirements. This program will focus on development of TBC`s to meet the specific needs of power generation applications. The program is directed at developing a state-of-the-art coating system with a minimum coating life of 25,000 hours at service temperatures required to meet increasing operating efficiency goals. Westinghouse has assembled a team of university and industry leaders to accomplish this goal. Westinghouse will coordinate the efforts of all program participants. Chromalloy Turbine Technologies, Inc. and Sermatech International, Inc. will be responsible for bond coat and TBC deposition technology. Praxair Specialty Powders, Inc. will be responsible for the fabrication of all bond coat and ceramic powders for the program. Southwest Research Institute will head the life prediction modelling effort; they will also be involved in coordinating nondestructive evaluation (NDE) efforts. Process modelling will be provided by the University of Arizona.

  6. Alternative Fuels: Research Progress

    Directory of Open Access Journals (Sweden)

    Maher A.R. Sadiq Al-Baghdadi

    2013-01-01

    Full Text Available Chapter 1: Pollutant Emissions and Combustion Characteristics of Biofuels and Biofuel/Diesel Blends in Laminar and Turbulent Gas Jet Flames. R. N. Parthasarathy, S. R. Gollahalli Chapter 2: Sustainable Routes for The Production of Oxygenated High-Energy Density Biofuels from Lignocellulosic Biomass. Juan A. Melero, Jose Iglesias, Gabriel Morales, Marta Paniagua Chapter 3: Optical Investigations of Alternative-Fuel Combustion in an HSDI Diesel Engine. T. Huelser, M. Jakob, G. Gruenefeld, P. Adomeit, S. Pischinger Chapter 4: An Insight into Biodiesel Physico-Chemical Properties and Exhaust Emissions Based on Statistical Elaboration of Experimental Data. Evangelos G. Giakoumis Chapter 5: Biodiesel: A Promising Alternative Energy Resource. A.E. Atabani Chapter 6: Alternative Fuels for Internal Combustion Engines: An Overview of the Current Research. Ahmed A. Taha, Tarek M. Abdel-Salam, Madhu Vellakal Chapter 7: Investigating the Hydrogen-Natural Gas Blends as a Fuel in Internal Combustion Engine. ?lker YILMAZ Chapter 8: Conversion of Bus Diesel Engine into LPG Gaseous Engine; Method and Experiments Validation. M. A. Jemni , G. Kantchev , Z. Driss , R. Saaidia , M. S. Abid Chapter 9: Predicting the Combustion Performance of Different Vegetable Oils-Derived Biodiesel Fuels. Qing Shu, ChangLin Yu Chapter 10: Production of Gasoline, Naphtha, Kerosene, Diesel, and Fuel Oil Range Fuels from Polypropylene and Polystyrene Waste Plastics Mixture by Two-Stage Catalytic Degradation using ZnO. Moinuddin Sarker, Mohammad Mamunor Rashid

  7. State alternative route designations

    Energy Technology Data Exchange (ETDEWEB)

    1989-07-01

    Pursuant to the Hazardous Materials Transportation Act (HMTA), the Department of Transportation (DOT) has promulgated a comprehensive set of regulations regarding the highway transportation of high-level radioactive materials. These regulations, under HM-164 and HM-164A, establish interstate highways as the preferred routes for the transportation of radioactive materials within and through the states. The regulations also provide a methodology by which a state may select alternative routes. First,the state must establish a ``state routing agency,`` defined as an entity authorized to use the state legal process to impose routing requirements on carriers of radioactive material (49 CFR 171.8). Once identified, the state routing agency must select routes in accordance with Large Quantity Shipments of Radioactive Materials or an equivalent routing analysis. Adjoining states and localities should be consulted on the impact of proposed alternative routes as a prerequisite of final route selection. Lastly, the states must provide written notice of DOT of any alternative route designation before the routes are deemed effective.

  8. State alternative route designations

    Energy Technology Data Exchange (ETDEWEB)

    1989-07-01

    Pursuant to the Hazardous Materials Transportation Act (HMTA), the Department of Transportation (DOT) has promulgated a comprehensive set of regulations regarding the highway transportation of high-level radioactive materials. These regulations, under HM-164 and HM-164A, establish interstate highways as the preferred routes for the transportation of radioactive materials within and through the states. The regulations also provide a methodology by which a state may select alternative routes. First,the state must establish a state routing agency,'' defined as an entity authorized to use the state legal process to impose routing requirements on carriers of radioactive material (49 CFR 171.8). Once identified, the state routing agency must select routes in accordance with Large Quantity Shipments of Radioactive Materials or an equivalent routing analysis. Adjoining states and localities should be consulted on the impact of proposed alternative routes as a prerequisite of final route selection. Lastly, the states must provide written notice of DOT of any alternative route designation before the routes are deemed effective.

  9. Is garlic alternative medicine?

    Science.gov (United States)

    Rivlin, Richard S

    2006-03-01

    Garlic has been used medicinally since antiquity. In virtually every early civilization known, such as ancient India, Egypt, Rome, China, and Japan, garlic was part of the therapeutic regimen for a variety of maladies. Therefore, the ancient medicinal tradition of garlic use would qualify it as a folk medicine or as an alternative or complementary medicine. But is garlic an alternative to established methods of disease prevention or treatment? Scientists from around the world have identified a number of bioactive substances in garlic that are water soluble (e.g., S-allyl methylcysteine), and fat soluble (e.g., diallyldisulfide). Mechanisms of action are being elucidated by modern technology. The validity of ancient medicine is now being evaluated critically in cell-free systems, animal models, and human populations. Preventive and therapeutic trials of garlic are still in early stages. There are many promising lines of research suggesting the potential effects of garlic. The current state of knowledge does not recognize garlic as a true alternative, but it will likely find a place for garlic as a complement to established methods of disease prevention and treatment. Our goal should be to examine garlic together with other agents to evaluate its possible efficacy and toxicity under conditions of actual use in humans. PMID:16484549

  10. Alternative Energy Sources

    CERN Document Server

    Michaelides, Efstathios E (Stathis)

    2012-01-01

    Alternative Energy Sources is designed to give the reader, a clear view of the role each form of alternative energy may play in supplying the energy needs of the human society in the near and intermediate future (20-50 years).   The two first chapters on energy demand and supply and environmental effects, set the tone as to why the widespread use of alternative energy is essential for the future of human society. The third chapter exposes the reader to the laws of energy conversion processes, as well as the limitations of converting one energy form to another. The sections on exergy give a succinct, quantitative background on the capability/potential of each energy source to produce power on a global scale. The fourth, fifth and sixth chapters are expositions of fission and fusion nuclear energy. The following five chapters (seventh to eleventh) include detailed descriptions of the most common renewable energy sources – wind, solar, geothermal, biomass, hydroelectric – and some of the less common sources...

  11. Richards Barrier LA Reference Design Feature Evaluation

    International Nuclear Information System (INIS)

    The Richards Barrier is one of the design features of the repository to be considered for the License Application (LA), Richards was a soil scientist who first described the diversion of moisture between two materials with different hydrologic properties. In this report, a Richards Barrier is a special type of backfill with a fine-grained material (such as sand) overlaying a coarse-grained material (such as gravel). Water that enters an emplacement drift will first encounter the fine-grained material and be transported around the coarse-grained material covering the waste package, thus protecting the waste package from contact with most of the groundwater. The objective of this report is to discuss the benefits and liabilities to the repository by the inclusion of a Richards Barrier type backfill in emplacement drifts. The Richards Barrier can act as a barrier to water flow, can reduce the waste package material dissolution rate, limit mobilization of the radionuclides, and can provide structural protection for the waste package. The scope of this report is to: (1) Analyze the behavior of barrier materials following the intrusion of groundwater for influxes of 1 to 300 mm per year. The report will demonstrate diversion of groundwater intrusions into the barrier over an extended time period when seismic activity and consolidation may cause the potential for liquefaction and settlement of the Richards Barrier. (2) Review the thermal effects of the Richards Barrier on material behavior. (3) Analyze the effect of rockfall on the performance of the Richards Barrier and the depth of the barrier required to protect waste packages under the barrier. (4) Review radiological and heating conditions on placement of multiple layers of the barrier. Subsurface Nuclear Safety personnel will perform calculations to determine the radiation reduction-time relationship and shielding capacity of the barrier. (5) Evaluate the effects of ventilation on cooling of emplacement drifts and

  12. Origin of translocation barriers for polyelectrolyte chains.

    Science.gov (United States)

    Kumar, Rajeev; Muthukumar, M

    2009-11-21

    For single-file translocations of a charged macromolecule through a narrow pore, the crucial step of arrival of an end at the pore suffers from free energy barriers, arising from changes in intrachain electrostatic interaction, distribution of ionic clouds and solvent molecules, and conformational entropy of the chain. All contributing factors to the barrier in the initial stage of translocation are evaluated by using the self-consistent field theory for the polyelectrolyte and the coupled Poisson-Boltzmann description for ions without radial symmetry. The barrier is found to be essentially entropic due to conformational changes. For moderate and high salt concentrations, the barriers for the polyelectrolyte chain are quantitatively equivalent to that of uncharged self-avoiding walks. Electrostatic effects are shown to increase the free energy barriers, but only slightly. The degree of ionization, electrostatic interaction strength, decreasing salt concentration, and the solvent quality all result in increases in the barrier. PMID:19929072

  13. Barrier experiment: Shock initiation under complex loading

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-01-12

    The barrier experiments are a variant of the gap test; a detonation wave in a donor HE impacts a barrier and drives a shock wave into an acceptor HE. The question we ask is: What is the trade-off between the barrier material and threshold barrier thickness to prevent the acceptor from detonating. This can be viewed from the perspective of shock initiation of the acceptor subject to a complex pressure drive condition. Here we consider key factors which affect whether or not the acceptor undergoes a shock-to-detonation transition. These include the following: shock impedance matches for the donor detonation wave into the barrier and then the barrier shock into the acceptor, the pressure gradient behind the donor detonation wave, and the curvature of detonation front in the donor. Numerical simulations are used to illustrate how these factors affect the reaction in the acceptor.

  14. Sunk Costs and Antitrust Barriers to Entry

    OpenAIRE

    SCHMALENSEE, Richard

    2004-01-01

    US antitrust policy takes as its objective consumer welfare, not total economic welfare. With that objective, Joe Bain's definition of entry barriers is more useful than George Stigler's or definitions based on economic welfare. It follows that economies of scale that involve sunk costs may create antitrust barriers to entry. A simple model shows that sunk costs without scale economies may discourage entry without creating an antitrust entry barrier.

  15. Transport Properties for Triangular Barriers in Graphene

    OpenAIRE

    Mouhafid, Abderrahim El; Jellal, Ahmed

    2013-01-01

    We theoretically study the electronic transport properties of Dirac fermions through one and double triangular barriers in graphene. Using the transfer matrix method, we determine the transmission, conductance and Fano factor. They are obtained to be various parameters dependent such as well width, barrier height and barrier width. Therefore, different discussions are given and comparison with the previous significant works is done. In particular, it is shown that at Dirac point the Dirac fer...

  16. Barriers to nursing care in emergency wards

    OpenAIRE

    Mahmoudi, Hosein; Mohmmadi, Eesa; Abbas EBADI

    2013-01-01

    Background: Caring is the essence of nursing. Since care is influenced by cultural, economic, and social factors, various diverse barriers exist in the realization of care. The aim of the study was to clarify barriers to caring in emergency patients based on experiences of nurses and patients and their relatives. Materials and Methods: A qualitative design of content analysis was used to identify the barriers to caring in emergency patients. In-depth interviews were conducted with 18 Iranian ...

  17. Identification of Key Barriers in Workforce Development

    Energy Technology Data Exchange (ETDEWEB)

    None

    2008-03-31

    This report documents the identification of key barriers in the development of an adequate national security workforce as part of the National Security Preparedness Project, being performed under a Department of Energy/National Nuclear Security Administration grant. Many barriers exist that prevent the development of an adequate number of propertly trained national security personnel. Some barriers can be eliminated in a short-term manner, whereas others will involve a long-term strategy that takes into account public policy.

  18. Assessing Non-tariff Barriers in Syria

    OpenAIRE

    Chemingui, Mohamed Abdelbasset; Dessus, Sebastien

    2008-01-01

    International trade in Syria is highly regulated through a combination of tariffs and non-tariff barriers. At 8% of the value of imports on average, effective tariffs are relatively low. However, non-tariff barriers to trade actually make Syria's trade restrictiveness very high. Comparing world and domestic prices of imports indeed suggests that non-tariff barriers increase the domestic price of imported goods by 17% on average, notably the result of significant quantitative restrictions. Usi...

  19. Blood cells and endothelial barrier function

    OpenAIRE

    Rodrigues, Stephen F.; Granger, D Neil

    2015-01-01

    The barrier properties of endothelial cells are critical for the maintenance of water and protein balance between the intravascular and extravascular compartments. An impairment of endothelial barrier function has been implicated in the genesis and/or progression of a variety of pathological conditions, including pulmonary edema, ischemic stroke, neurodegenerative disorders, angioedema, sepsis and cancer. The altered barrier function in these conditions is often linked to the release of solub...

  20. Edge transport barriers in magnetic fusion plasmas

    International Nuclear Information System (INIS)

    The present level of understanding of the physics of the formation and sustainment of edge transport barriers in magnetically confined fusion plasmas is presented. The formation of edge transport barriers is studied through evolution of mechanisms which can suppress plasma turbulence and so reduce turbulent driven transport, such as E x B flow shear stabilization of turbulence. Comparisons of theoretical studies with experimental results are described including investigations of zonal flows, which are considered important for saturation and self-regulation of turbulence and turbulence-driven transport. Processes that affect the dynamics and spatial structure of the edge barrier are described with emphasis on the width of the transport barrier. (authors)

  1. Water and contaminant movement: migration barriers

    International Nuclear Information System (INIS)

    Migration barriers are used in shallow land burial facilities to slow or stop the movement of water and contaminants and are discussed here as a single component embedded in a complex environmental system. Analytical solutions to solute transport equations are used to approximate the behavior of migration barriers and to derive design criteria for control of subsurface water and contaminant migration. Various types of migration barriers are compared and design recommendations are made for shallow land burial trench caps and liners. Needed improvements and suggested field experiments for future designs of migration barriers are then discussed relative to the management of low-level radioactive wastes

  2. Breaking down the barriers to commercialization of fuel cells in transportation through Government - industry R&D programs

    Energy Technology Data Exchange (ETDEWEB)

    Chalk, S.G. [Dept. of Energy, Washington, DC (United States); Venkateswaran, S.R. [Energetics, Inc., Columbia, MD (United States)

    1996-12-31

    PEM fuel cell technology is rapidly emerging as a viable propulsion alternative to the internal combustion engine. Fuel cells offer the advantages of low emissions, high efficiency, fuel flexibility, quiet and continuous operation, and modularity. Over the last decade, dramatic advances have been achieved in the performance and cost of PEM fuel cell technologies for automotive applications. However, significant technical barriers remain to making fuel cell propulsion systems viable alternatives to the internal combustion engine. This paper focuses on the progress achieved and remaining technical barriers while highlighting Government-industry R&D efforts that are accelerating fuel cell technology toward commercialization.

  3. Alternatives to nuclear energy

    International Nuclear Information System (INIS)

    This article discusses several possibilities as alternatives to nuclear energy and their relevance to the Philippine case. The major present and future fuel alternatives to petroleum and nuclear energy are coal, geothermal heat, solar energy and hydrogen, the first two of which are being used. Different conversion technologies are also discussed for large scale electricity production namely solar thermal electric conversion (STC), photovoltaic electric power system (PEPS) and ocean thermal energy conversion (OTEC). Major environmental considerations affect the choice of energy sources and technologies. We have the problem of long term accumulation of radioactive waste in the case of nuclear energy; in geothermal and fossil-fuels carbon dioxide uranium and accumulation may cause disastrous consequences. With regard to Philippine option, the greatest considerations in selecting alternative energy options would be resources availability - both energy and financial and technology status. For the country's energy plan, coal and geothermal energy are expected to play a significant role. The country's coal resources are 1.4 billion metric tons. For geothermal energy, 25 volcanic centers were identified and has a potential equivalent to 2.5 x 106 million barrels of oil. Solar energy if harnessed, being in the sunbelt, averaging some 2000 hours a year could be an energy source. The present dilemma of the policy maker is whether national resources are better spent on large scale urban-based energy projects or whether those should be focused on small scale, rural oriented installations which produced benefits to the more numerous and poorer members of the population. (RTD)

  4. Barriers to the health maintenance organization for the over 65's.

    Science.gov (United States)

    Titus, S L

    1982-01-01

    What are the barriers that impede and prevent those over age 65 from considering a health maintenance organization (HMO) as an alternative to traditional Medicare-supplementary insurance? In an attempt to answer this question, structured interviews were conducted with 260 elderly people. The barriers examined include knowledge deficits lack of exposure to information, general resistance to change, the difficulties of integrating the 'new' with old insurance patterns, and value stances that may limit the adoption of HMOs by some elderly. Also discussed are educational strategies that may enhance the possibility of the elderly's consideration of the HMO as a viable option. PMID:6758126

  5. Religious culture as a barrier?

    DEFF Research Database (Denmark)

    Agergaard, Sine

    2016-01-01

    Political interventions, media coverage and research often refer to the underrepresentation of ethnic minorities, particularly girls and women, participating in physical activity and organised sports. In both public and academic debates, reference is made to the religious culture as a particular...... barrier to participation in sports among Muslim girls and women. This article aims to provide a counter-narrative by focusing on young Muslim girls who simultaneously practice their religion and sports. The main research question was: How do young Danish Muslim girls align participation in sports with...... their religious and cultural frames of reference? The study uses a case study approach with interviews of ten 13–17-year-old Danish Muslim girls, as well as explorative observations in two football clubs and interviews with five coaches and club leaders. In further developing an analytical model for...

  6. Pratt & Whitney thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Bornstein, N. [United Technologies Research Center, East Hartford, CT (United States); Marcin, J. [Pratt & Whitney Aircraft Co., East Hartford, CT (United States)

    1995-10-01

    The objective of the Advanced Turbine Systems (ATS) Program is to develop ultra-high efficient, environmentally superior, and cost competitive gas turbine systems. The operating profiles of these industrial gas turbines are long, less cyclic with fewer transients-compared with those for aircraft gas turbine engines. Therefore, creep rather than thermal fatigue, becomes primary life-limiting for hot section components. Thermal barrier coatings (TBCs) will be used to achieve the objectives of the program. TBCs allow surface temperatures to increase without compromising the structural properties of the alloy. TBCs typically consist of a ceramic insulating layer, deposited onto the substrate with an intervening metallic layer, which imparts oxidation protection to the substrate and provides a surface to which the ceramic layer can adhere.

  7. Alternate fusion concepts

    International Nuclear Information System (INIS)

    This review summarizes the status of alternate fusion concepts and plans for their future. The concepts selected for review are those employing electromagnetic confinement for which there have been reasonable predictions of net energy gain from pure fusion and which have shown significant recent development or are the subjects of ongoing international activity. They include advanced tokamaks, stellarators, the spherical torus, reversed-field pinch and dense z-field pinch devices, field reversed configuration, and spheromaks. In addition, an overall view of the status of each concept with respect to achieving ignition and to reactor designs is presented

  8. Alternate fuels; Combustibles alternos

    Energy Technology Data Exchange (ETDEWEB)

    Romero Paredes R, Hernando; Ambriz G, Juan Jose [Universidad Autonoma Metropolitana. Iztapalapa (Mexico)

    2003-07-01

    In the definition and description of alternate fuels we must center ourselves in those technological alternatives that allow to obtain compounds that differ from the traditional ones, in their forms to be obtained. In this article it is tried to give an overview of alternate fuels to the conventional derivatives of petroleum and that allow to have a clear idea on the tendencies of modern investigation and the technological developments that can be implemented in the short term. It is not pretended to include all the tendencies and developments of the present world, but those that can hit in a relatively short term, in accordance with agreed with the average life of conventional fuels. Nevertheless, most of the conversion principles are applicable to the spectrum of carbonaceous or cellulosic materials which are in nature, are cultivated or wastes of organic origin. Thus one will approach them in a successive way, the physical, chemical and biological conversions that can take place in a production process of an alternate fuel or the same direct use of the fuel such as burning the sweepings derived from the forests. [Spanish] En la definicion y descripcion de combustibles alternos nos debemos centrar en aquellas alternativas tecnologicas que permitan obtener compuestos que difieren de los tradicionales, al menos en sus formas de ser obtenidos. En este articulo se pretende dar un panorama de los combustibles alternos a los convencionales derivados del petroleo y que permita tener una idea clara sobre las tendencias de la investigacion moderna y los desarrollos tecnologicos que puedan ser implementados en el corto plazo. No se pretende abarcar todas las tendencias y desarrollos del mundo actual, sino aquellas que pueden impactar en un plazo relativamente corto, acordes con la vida media de los combustibles convencionales. Sin embargo, la mayor parte de los principios de conversion son aplicables al espectro de materiales carbonaceos o celulosicos los cuales se

  9. Polyphase alternating codes

    OpenAIRE

    M. Markkanen; Vierinen, J.; Markkanen, J.

    2007-01-01

    We present a new class of alternating codes. Instead of the customary binary phase codes, the new codes utilize either p or p–1 phases, where p is a prime number. The first class of codes has code length pm, where m is a positive integer, the second class has code length p–1. We give an actual construction algorithm, and explain the principles behind it. We ...

  10. Polyphase alternating codes

    Directory of Open Access Journals (Sweden)

    M. Markkanen

    2008-08-01

    Full Text Available We present a new class of alternating codes. Instead of the customary binary phase codes, the new codes utilize either p or p–1 phases, where p is a prime number. The first class of codes has code length pm, where m is a positive integer, the second class has code length p–1. We give an actual construction algorithm, and explain the principles behind it. We handle a few specific examples in detail. The new codes offer an enlarged collection of code lengths for radar experiments.

  11. Alternate transportation system

    Science.gov (United States)

    Zertuche, Tony; Mckinnie, James

    1988-01-01

    Three missions have been identified by NASA for a Space Shuttle-supplementing Alternate Transportation System (ATS) encompassing combinations of booster vehicles, crew modules, and service modules: (1) to achieve manned access to orbit for Space Station crew rotation every 90 days, (2) the lofting of a logistics module resupplying the Space Station every 180 days, and (3) the simultaneous launch of both crews and logistics to the Space Station. A reentry glider is considered, in conjunction with the Space Shuttle's unmanned cargo version and the Apollo manned capsule, as an important ATS element. The Titan IV/NUS is used as a booster.

  12. Demonstration of close-coupled barriers for subsurface containment of buried waste

    International Nuclear Information System (INIS)

    The primary objective of this project is to develop and demonstrate a close-coupled barrier for the containment of subsurface waste or contaminant migration. A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed waste remediation plan. This paper will discuss the installation of a close-coupled barrier and the subsequent integrity verification. The demonstration will take place at a cold site at the Hanford Geotechnical Test Facility, 400 Area, Hanford, Washington

  13. Alternatives to fundholding.

    Science.gov (United States)

    Glennerster, H; Cohen, A; Bovell, V

    1998-01-01

    The new Labour government in the United Kingdom is proposing to adapt the reforms begun by the last Thatcher government. In particular, it is proposing to abolish the most controversial element--general practitioner (GP) fundholding. It is looking for alternatives. The study reported here followed and evaluated several such schemes. While fundholders use their purchasing power directly to force change by threatening "exit" to another provider, other GPs have evolved ways of influencing decisions--enhancing their "voice." The authors develop a theory to predict the conditions favoring the relative success of exit and voice strategies in health purchasing, and describe alternative GP-based purchasing schemes and the reasons they evolved in six sample districts. In four of these districts and eight practices in each, fundholding and non-fundholding GPs were then asked to describe their intentions and the outcomes of the purchasing process in which they had participated. Four specialties were taken as examples. The authors compare the relative success of fundholders and non-fundholders in achieving their objectives. PMID:9493753

  14. Alternative Medicine and Your Child

    Science.gov (United States)

    ... to Know About Zika & Pregnancy Complementary and Alternative Medicine KidsHealth > For Parents > Complementary and Alternative Medicine Print ... works. previous continue How CAM Differs From Traditional Medicine CAM is frequently distinguished by its holistic methods, ...

  15. Pea Island Alternatives Development Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this Alternatives Development Report is to outline,in broad scope, the options, tools and alternatives available to the US Fish and Wildlife Service...

  16. Alternative splicing and muscular dystrophy

    OpenAIRE

    Pistoni, Mariaelena; Ghigna, Claudia; Gabellini, Davide

    2010-01-01

    Alternative splicing of pre-mRNAs is a major contributor to proteomic diversity and to the control of gene expression in higher eukaryotic cells. For this reasons, alternative splicing is tightly regulated in different tissues and developmental stages and its disruption can lead to a wide range of human disorders. The aim of this review is to focus on the relevance of alternative splicing for muscle function and muscle disease. We begin by giving a brief overview of alternative splicing, musc...

  17. Gastrointestinal mucosal barrier function and diseases.

    Science.gov (United States)

    Oshima, Tadayuki; Miwa, Hiroto

    2016-08-01

    The gastrointestinal mucosal barrier plays an essential role in the separation of the inside of the body from the outside environment. Tight junctions (TJs) are the most important component for construction of a constitutive barrier of epithelial cells, and they regulate the permeability of the barrier by tightly sealing the cell-cell junctions. TJ proteins are represented by claudins, occludin, junctional adhesion molecules, and scaffold protein zonula occludens. Among these TJ proteins, claudins are the major components of TJs and are responsible for the barrier and the polarity of the epithelial cells. Gastrointestinal diseases including reflux esophagitis, inflammatory bowel disease, functional gastrointestinal disorders, and cancers may be regulated by these molecules, and disruption of their functions leads to chronic inflammatory conditions and chronic or progressive disease. Therefore, regulation of the barrier function of epithelial cells by regulating the expression and localization of TJ proteins is a potential new target for the treatment of these diseases. Treatment strategies for these diseases might thus be largely altered if symptom generation and/or immune dysfunction could be regulated through improvement of mucosal barrier function. Since TJ proteins may also modify tumor infiltration and metastasis, other important goals include finding a good TJ biomarker of cancer progression and patient prognosis, and developing TJ protein-targeted therapies that can modify patient prognosis. This review summarizes current understanding of gastrointestinal barrier function, TJ protein expression, and the mechanisms underlying epithelial barrier dysregulation in gastrointestinal diseases. PMID:27048502

  18. Barrier fuel demonstrated at Quad Cities 2

    International Nuclear Information System (INIS)

    The article describes the nuclear design of the 144 zirconium barrier bundles inserted in the Quad Cities 2 core in December 1981, their locations and power history during their first cycle of irradiation, and the resulting linear heat generation rates (LHGRs) and fuel rod burnups when 16 of these zirconium barrier bundles were power ramped in March 1983. (author)

  19. Complementary Barrier Infrared Detector (CBIRD) Contact Methods

    Science.gov (United States)

    Ting, David Z.; Hill, Cory J.; Gunapala, Sarath D.

    2013-01-01

    The performance of the CBIRD detector is enhanced by using new device contacting methods that have been developed. The detector structure features a narrow gap adsorber sandwiched between a pair of complementary, unipolar barriers that are, in turn, surrounded by contact layers. In this innovation, the contact adjacent to the hole barrier is doped n-type, while the contact adjacent to the electron barrier is doped p-type. The contact layers can have wider bandgaps than the adsorber layer, so long as good electrical contacts are made to them. If good electrical contacts are made to either (or both) of the barriers, then one could contact the barrier(s) directly, obviating the need for additional contact layers. Both the left and right contacts can be doped either n-type or ptype. Having an n-type contact layer next to the electron barrier creates a second p-n junction (the first being the one between the hole barrier and the adsorber) over which applied bias could drop. This reduces the voltage drop over the adsorber, thereby reducing dark current generation in the adsorber region.

  20. Barriers to adherence in cystic fibrosis

    DEFF Research Database (Denmark)

    Bregnballe, Vibeke; Schiøtz, Peter Oluf

    2012-01-01

    Danish patients with cystic fibrosis aged 14 to 25 years and their parents. Conclusions: The present study showed that the majority of adolescents with CF and their parents experienced barriers to treatment adherence. Patients and parents agreed that the three most common barriers encountered lack of...

  1. Rotational barriers in perylene fluorescent dyes

    OpenAIRE

    Langhals, Heinz; Demmig, Stefan; Huber, Helmut

    1988-01-01

    Rotational barriers in N-substituted perylene dyes have been determined. Phenyl substituents with tert-butyl groups in the o-position give rigid systems, whereas secondary alkyl groups cause low rotational barriers. In spite of that, fluorescent quantum yields are high in both cases. Conformations in solution are discussed.

  2. A STUDY OF BARRIERS IN BRIDGING COMMUNICATION

    OpenAIRE

    Niteen V. Dandekar

    2014-01-01

    The main objective of this paper is to make a thought provoking discussion on the role barriers in bridging communication. It focuses on the concept of communication, process and the role of language related barriers in bridging communication. It studies the significance of communication in modern human life.

  3. K-Basin isolation barrier seal

    International Nuclear Information System (INIS)

    This report documents various aspects of the design, analysis, procurement, and fabrication of the hydraulic seal on the isolation barriers to be installed in the 100-K Area spent nuclear fuel basin. The isolation barrier is used to keep water in the basin in the event of an earthquake

  4. Barrier properties of natural clay minerals

    OpenAIRE

    Дудар, Т.В.; С.П. Бугера; В.М. Кадошніков; Б.П. Злобенко

    2009-01-01

     Clay minerals is a perfect material for geochemical barrier due to their high water resistivity, plasticity, high sorbing capacity, well developed surface and cheapness in extraction and processing. This work studies the peculiarities of uranium sorbtion on clay minerals on the example of bentonite and palygorskite clay from Cherkassy deposit, and clay usage as a barrier material.

  5. Barrier properties of natural clay minerals

    Directory of Open Access Journals (Sweden)

    Т.В. Дудар

    2009-01-01

    Full Text Available  Clay minerals is a perfect material for geochemical barrier due to their high water resistivity, plasticity, high sorbing capacity, well developed surface and cheapness in extraction and processing. This work studies the peculiarities of uranium sorbtion on clay minerals on the example of bentonite and palygorskite clay from Cherkassy deposit, and clay usage as a barrier material.

  6. Addressing Regulatory Software Barriers to Business Growth

    OpenAIRE

    Kularatne, Chandana; Lopez-Calix, Jose

    2012-01-01

    This policy paper explores the relative importance of the software regulatory barriers to growth in Pakistan. Such software barriers have been identified as part of the major constraint in the Framework for Economic Growth of the Government of Pakistan. Indeed, adequate software is needed to provide an environment in which the hardware of growth (physical infrastructure) could be expanded ...

  7. ALTERNATIVE FUELS FOR DIESEL ENGINES

    Directory of Open Access Journals (Sweden)

    Jacek Caban

    2013-12-01

    Full Text Available This paper presents the development and genesis of the use of alternative fuels in internal combustion ignition engines. Based on the analysis of the literature, this article shows various alternative fuels used in Poland and all over the world. Furthermore, this article describes the research directions for alternative fuels use in road transport powered by diesel engines.

  8. ALTERNATIVE FUELS FOR DIESEL ENGINES

    OpenAIRE

    Jacek Caban; Agata Gniecka; Lukáš Holeša

    2013-01-01

    This paper presents the development and genesis of the use of alternative fuels in internal combustion ignition engines. Based on the analysis of the literature, this article shows various alternative fuels used in Poland and all over the world. Furthermore, this article describes the research directions for alternative fuels use in road transport powered by diesel engines.

  9. Alternative energy sources

    Energy Technology Data Exchange (ETDEWEB)

    Michaelides, Efstathios E. (Stathis) [Texas Christian Univ., Forth Worth, TX (United States). Dept. of Engineering

    2012-07-01

    Alternative Energy Sources is designed to give the reader, a clear view of the role each form of alternative energy may play in supplying the energy needs of the human society in the near and intermediate future (20-50 years). The two first chapters on energy demand and supply and environmental effects, set the tone as to why the widespread use of alternative energy is essential for the future of human society. The third chapter exposes the reader to the laws of energy conversion processes, as well as the limitations of converting one energy form to another. The sections on exergy give a succinct, quantitative background on the capability/potential of each energy source to produce power on a global scale. The fourth, fifth and sixth chapters are expositions of fission and fusion nuclear energy. The following five chapters (seventh to eleventh) include detailed descriptions of the most common renewable energy sources - wind, solar, geothermal, biomass, hydroelectric - and some of the less common sources, such as tidal and wave energy. The emphasis of these chapters is on the global potential of each source; the engineering/technical systems that are currently used in harnessing the potential of each one of these energy sources; the technological developments that will contribute to wider utilization of the sources; and the environmental effects associated with their current and their wider use. The last three chapters are: energy storage, which is the main limitation of the wider use of solar and wind power and will become an important issue if renewable energy sources are to be used widely; energy conservation, which appears to be everyone's favorite issue, but by itself is not a solution to our energy challenge; and energy economics, a necessary consideration in market-driven economies. The fourteen chapters in the book have been chosen so that one may fit a semester University course around this book. At the end of every chapter, there are 12-20 problems

  10. Fungal penetration of defensive barriers of plants

    International Nuclear Information System (INIS)

    Plants, like all other living organisms, are packaged in an outer envelope which acts as the barrier between the plant and its environment. The outer envelop of the aerial parts of plants (the cuticle) consists of a polyester, called cutin, which is embedded in a soluble mixture of relatively nonpolar lipids, collectively called waxes. The insoluble structural polymer, cutin, constitutes the major barrier to invasion by pathogenic microbes. The underground parts and aerially formed periderms and barks are protected by a different type of insoluble polymeric material called suberin. This polymer is also associated with waxes which make this layer resistant to diffusion. It has been known for a long period of time that these protective barriers are breached by pathogenic fungi. In this chapter, the nature of these barriers and how pathogenic fungi penetrate such barriers during infection are discussed. Topics include the composition, location and ultrastructure of cutin and suberin; and the isolation and properties of cutinase

  11. Alternative tsunami models

    Energy Technology Data Exchange (ETDEWEB)

    Tan, A; Lyatskaya, I [Department of Physics, Alabama A and M University, Normal, AL 35762 (United States)], E-mail: arjun.tan@aamu.edu

    2009-01-15

    The interesting papers by Margaritondo (2005 Eur. J. Phys. 26 401) and by Helene and Yamashita (2006 Eur. J. Phys. 27 855) analysed the great Indian Ocean tsunami of 2004 using a simple one-dimensional canal wave model, which was appropriate for undergraduate students in physics and related fields of discipline. In this paper, two additional, easily understandable models, suitable for the same level of readership, are proposed: one, a two-dimensional model in flat space, and two, the same on a spherical surface. The models are used to study the tsunami produced by the central Kuril earthquake of November 2006. It is shown that the two alternative models, especially the latter one, give better representations of the wave amplitude, especially at far-flung locations. The latter model further demonstrates the enhancing effect on the amplitude due to the curvature of the Earth for far-reaching tsunami propagation.

  12. LIU: exploring alternative ideas

    CERN Document Server

    Damerau, H; Garoby, R; Gilardoni, S; Hancock, S; Mikulec, B; Papaphilippou, Y; Rumolo, G; Shaposhnikova, E; Tomas, R

    2014-01-01

    The baseline upgrade scenarios for the injector complex cover the connection of Linac4 to the PSB, the increase of the PSB-PS transfer energy from 1 . 4 GeV to 2 GeV and the major SPS RF upgrade during LS2. The achievable beam characteristics will nonetheless remain below the expectation of the HL-LHC project. Therefore, alternative or additional options like, e.g., special bunch distributions, the use of injection optics optimized for high space charge or extra RF systems will be discussed. The expected beam parameters, possible implementation and impact on beam availability for these more exotic options will be analysed and compared to the LIU baseline plan. Moreover, the potential interest of further batch compression schemes will be evaluated.

  13. Altern als Widerstand

    Directory of Open Access Journals (Sweden)

    Roberta Maierhofer

    2005-07-01

    Full Text Available Gullettes kulturwissenschaftliche Untersuchung Aged by Culture ist wie bereits ihre zwei vorangehenden Werke, die sich mit Altern beschäftigen – Safe at Last in the Middle Years: The Invention of the Midlife Progress Novel (1988 und Declining to Decline. Cultural Combat and the Politics of the Middle (1997 –, von großem persönlichen Engagement und durch ein politisches Anliegen motiviert. Sowohl die Dringlichkeit als auch der Widerstand, den Gullette, die sich als „age critic“ definiert, als moralische und politische Notwendigkeit postuliert, werden in der Zweiteilung der Abhandlung angesprochen: „Cultural Urgencies“ und „Theorizing Age Resistantly“. Während Gullette den Begriff „aged by culture“ bereits in Declining to Decline einführt, stellt sie ihn nun in den Mittelpunkt ihrer Untersuchung. Das Buch ist einerseits einer gesellschaftspolitischen Analyse der USA gewidmet, andererseits wird eine Theorie des Widerstands gegenüber Altersdiskriminierung entwickelt.

  14. Alternate laser fusion drivers

    International Nuclear Information System (INIS)

    One objective of research on inertial confinement fusion is the development of a power generating system based on this concept. Realization of this goal will depend on the availability of a suitable laser or other system to drive the power plant. The primary laser systems used for laser fusion research, Nd3+: Glass and CO2, have characteristics which may preclude their use for this application. Glass lasers are presently perceived to be incapable of sufficiently high average power operation and the CO2 laser may be limited by and issues associated with target coupling. These general perceptions have encouraged a search for alternatives to the present systems. The search for new lasers has been directed generally towards shorter wavelengths; most of the new lasers discovered in the past few years have been in the visible and ultraviolet region of the spectrum. Virtually all of them have been advocated as the most promising candidate for a fusion driver at one time or another

  15. An Alternative to Tensors

    Science.gov (United States)

    Brown, Eric

    2008-10-01

    Some of the most beautiful and complex theories in physics are formulated in the language of tensors. While powerful, these methods are sometimes daunting to the uninitiated. I will introduce the use of Clifford Algebra as a practical alternative to the use of tensors. Many physical quantities can be represented in an indexless form. The boundary between the classical and the quantum worlds becomes a little more transparent. I will review some key concepts, and then talk about some of the things that I am doing with this interesting and powerful tool. Of note to some will be the development of rigid body dynamics for a game engine. Others may be interested in expressing the connection on a spin bundle. My intent is to prove to the audience that there exists an accessible mathematical tool that can be employed to probe the most difficult of topics in physics.

  16. Alternatives to neoliberalism?

    DEFF Research Database (Denmark)

    Warring, Niels; Ahrenkiel, Annegrethe; Nielsen, Birger Steen;

    This paper will discuss the consequences of neoliberal governance in Danish day care centres, the social educators’ response, and the possible development of alternatives based on collective participation of social educators and union representatives. We will show how important and unnoticed...... professional competencies come under pressure, and how collective interest representation is challenged. We will discuss how concepts of “gestural knowledge”, “coherence” and “rhythm” open for a new understanding of professional competence. And we will conclude that the social educators and their unions have...... the possibility to contribute to the development of a new welfare paradigm. The paper is based on material from two research projects (Ahrenkiel et al. 2009, 2011) involving social educators and union representatives in day care institutions. We have observed everyday work activities in day care...

  17. BIODIESEL – ALTERNATIVE FUEL

    Directory of Open Access Journals (Sweden)

    Darko Kiš

    2006-06-01

    Full Text Available A limited quantity of oil, the purchase of which also involves major expenses has become an important factor for intensive search and use of alternative fuels. Biodiesel is used in diesel engines, and is manufactured from vegetable oils, animal fats and recycled edible oils. The production and use of biodiesel are very important not only because of its economic and strategic connotations but also because of its environmental advantages. Favourable conditions in Croatia give good opportunities for a self-sufficient oil rape production, possibility for its intensification and employment of a number of people in both the agricultural production and biodiesel production plants. This paper presents a survey of the biodiesel fuel production, the characteristics and impacts it has on the biodiesel engine features as well as its impact on the environment.

  18. Green Barrier Promotes SustainableDevelopment of Our Foreign Trade

    OpenAIRE

    Yongning Wang

    2009-01-01

    Green barrier is a kind of new non-tariff barrier in the current international trade. This paper based on the meaning of green barrier, analyzed green barrier can promote Sustainable Development of our foreign trade, and proposed counter strategies to green barrier.

  19. 49 CFR 587.18 - Dimensions of fixed rigid barrier.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Dimensions of fixed rigid barrier. 587.18 Section... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) DEFORMABLE BARRIERS Offset Deformable Barrier § 587.18 Dimensions of fixed rigid barrier. (a) The fixed rigid barrier has a mass of...

  20. Elbilens tekniske og sociale barrierer

    OpenAIRE

    Møller, Tim Løye; Hansen, Søren; Jørgensen, Marc; Ferozi, Nader; Jürs, Jonathan; Kirkeskov, Georg; Fogh, Kasper Wandahl

    2012-01-01

    Abstract We live in a time in which the emission of CO2 and the scarcity of fossil fuels are becoming ever-present problems. An area deeply connected to this problem is our transportation system, which is almost completely based on oil. An alternative to this oil-based transportation system is the electric car. The problem is that the electric car does not have the same capabilities that the oil powered car possess and it is not completely CO2 neutral nor is it independent from fossil fuel...

  1. Institutional distributed energy interconnection barriers

    International Nuclear Information System (INIS)

    This PowerPoint presentation provided an introduction to Encorp Inc., a leading provider of network technology and infrastructure management solutions for the distributed energy market. Encorp develops and markets software and hardware technology solutions for communications, control and networking of distributed energy. It is developing and implementing real-time, distributed energy-focused solutions for a wide variety of applications through new products and services which are technology neutral, and easily networked. Encorp controls more than 500 MW of distributed power with a total of 127 customers. This paper reviewed 3 barriers (regulatory, contractual/tariffs, and business practices) based on US experience. The challenge remaining is to determine if microgrids can be used effectively, and to determine the limitations of bi-directional power flows. The key issues regarding how end-users can share the costs and maximize on the benefits of distributed energy resources include: standby service charges, departing load charges, regulatory uncertainty, rate class degradation, lack of incentives for utility cost reduction, and lack of ability to create experimental tariffs. tabs., figs

  2. African-American crack abusers and drug treatment initiation: barriers and effects of a pretreatment intervention

    Directory of Open Access Journals (Sweden)

    Lam Wendy KK

    2007-03-01

    Full Text Available Abstract Background Individual and sociocultural factors may pose significant barriers for drug abusers seeking treatment, particularly for African-American crack cocaine abusers. However, there is evidence that pretreatment interventions may reduce treatment initiation barriers. This study examined the effects of a pretreatment intervention designed to enhance treatment motivation, decrease crack use, and prepare crack abusers for treatment entry. Methods Using street outreach, 443 African-American crack users were recruited in North Carolina and randomly assigned to either the pretreatment intervention or control group. Results At 3-month follow-up, both groups significantly reduced their crack use but the intervention group participants were more likely to have initiated treatment. Conclusion The intervention helped motivate change but structural barriers to treatment remained keeping actual admissions low. Policy makers may be interested in these pretreatment sites as an alternative to treatment for short term outcomes.

  3. EVALUATION OF AMENDMENTS FOR MENDING THE INSITU REDOX MANIPULATION (ISRM) BARRIER

    Energy Technology Data Exchange (ETDEWEB)

    PETERSEN, S.W.

    2006-02-07

    In May of 2004, the U.S. Department of Energy (DOE) Richland and Fluor Hanford requested technical assistance from DOE Headquarters EM-23 to provide a team of technical experts to evaluate likely chemical/biological amendments for mending the In Situ Redox Manipulation (ISRM) Barrier in the 100-D Area of the Hanford Site. This request was a follow-on to an earlier request for assistance regarding the cause of chromium (Cr) breakthrough and recommendations for mending the barrier (March 2004 workshop). This report provides written documentation of the team's findings and recommendations. In 1995, a plume of dissolved hexavalent chromium [Cr(VI)] was discovered along the Columbia River shoreline and in the 100-D Area. Between 1999 and 2003, a reactive barrier using the ISRM technology, was installed at a distance of 680 meters along the river to reduce the Cr(VI) in the groundwater. The ISRM technology creates a treatment zone within the aquifer by injection of sodium dithionite, a strong reducing agent that scavenges dissolved oxygen (DO) from the aquifer and reduces ferric iron [Fe(III)], related metals, and oxy-ions. Bench-scale and field-scale treatability tests were conducted to demonstrate proof-of principle and to estimate barrier longevity, calculated to be in excess of twenty years. However, several years after initial and secondary treatment, groundwater in approximately 17 wells has been found to contain elevated Cr concentrations. The March 2004 technical assistance team (TAT) identified potential causes of Cr breakthrough as likely related to physical and chemical heterogeneity within the aquifer (including loss of reductive capacity within preferential flow paths) and the presence of other oxidants (DO and nitrate) significantly affecting the reductive capacity of the treated aquifer. These aquifer characteristics may limit the ability of alternative amendments to extend the reducing capacity of the barrier. A 2001 Bechtel Hanford report and

  4. Numerical simulations of capillary barrier field tests

    Energy Technology Data Exchange (ETDEWEB)

    Morris, C.E. [Univ. of Wollongong (Australia); Stormont, J.C. [Univ. of New Mexico, Albuquerque, NM (United States)

    1997-12-31

    Numerical simulations of two capillary barrier systems tested in the field were conducted to determine if an unsaturated flow model could accurately represent the observed results. The field data was collected from two 7-m long, 1.2-m thick capillary barriers built on a 10% grade that were being tested to investigate their ability to laterally divert water downslope. One system had a homogeneous fine layer, while the fine soil of the second barrier was layered to increase its ability to laterally divert infiltrating moisture. The barriers were subjected first to constant infiltration while minimizing evaporative losses and then were exposed to ambient conditions. The continuous infiltration period of the field tests for the two barrier systems was modelled to determine the ability of an existing code to accurately represent capillary barrier behavior embodied in these two designs. Differences between the field test and the model data were found, but in general the simulations appeared to adequately reproduce the response of the test systems. Accounting for moisture retention hysteresis in the layered system will potentially lead to more accurate modelling results and is likely to be important when developing reasonable predictions of capillary barrier behavior.

  5. HgCdTe barrier infrared detectors

    Science.gov (United States)

    Kopytko, M.; Rogalski, A.

    2016-05-01

    In the last decade, new strategies to achieve high-operating temperature (HOT) detectors have been proposed, including barrier structures such as nBn devices, unipolar barrier photodiodes, and multistage (cascade) infrared detectors. The ability to tune the positions of the conduction and valence band edges independently in a broken-gap type-II superlattices is especially helpful in the design of unipolar barriers. This idea has been also implemented in HgCdTe ternary material system. However, the implementation of this detector structure in HgCdTe material system is not straightforward due to the existence of a valence band discontinuity (barrier) at the absorber-barrier interface. In this paper we present status of HgCdTe barrier detectors with emphasis on technological progress in fabrication of MOCVD-grown HgCdTe barrier detectors achieved recently at the Institute of Applied Physics, Military University of Technology. Their performance is comparable with state-of-the-art of HgCdTe photodiodes. From the perspective of device fabrication their important technological advantage results from less stringent surface passivation requirements and tolerance to threading dislocations.

  6. Advances in research on labyrinth membranous barriers

    Institute of Scientific and Technical Information of China (English)

    Wenfang Sun; Wuqing Wang

    2015-01-01

    Integrity of the membranous labyrinth barrier system is of critical importance, which promotes inner ear homeostasis and maintains its features. The membranous labyrinth barrier system is divided into several subsets of barriers which, although independent from each other, are interrelated. The same substance may demonstrate different permeability characteristics through different barriers and under different conditions, while different substances can have different permeability features even in the same barrier under the same condition. All parts of the mem-branous labyrinth barrier structure, including their morphology, enzymes and channel proteins, and theirs permeability characteristics under various physiological and pathological conditions are reviewed in this paper. Infections, noise exposure, ototoxicity may all increase perme-ability of the barriers and lead to disturbances in inner ear homeostasis. Copyright © 2015 The Authors. Production & hosting by Elsevier (Singapore) Pte Ltd On behalf of PLA General Hospital Department of Otolaryngology Head and Neck Surgery. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  7. Implementation of power barrier option valuation

    Science.gov (United States)

    Cahyani, Agatha C. P.; Sumarti, Novriana

    2015-09-01

    Options are financial instruments that can be utilized to reduce risk in stock investment. Barrier options are one of the major types of options actively used in financial markets where its life period depends on the path of the underlying stock prices. The features of the barrier option can be used to modify other types of options. In this research, the barrier option will be implemented into power option, so it is called power barrier option. This option is an extension of the vanilla barrier options where the Call payoff being considered is defined as P C =max (STβ-Kβ,0 ) , and the Put payoff being considered is defined as P P =max (Kβ-STβ,0 ) . Here β > 0 and β ≠ 1, K is the strike price of the option, and ST is the price of the underlying stock at time maturity T. In this paper, we generate the prices of stock using binomial method which is adjusted to the power option. In the conclusion, the price of American power barrier option is more expensive than the price of European power barrier option.

  8. Blood cells and endothelial barrier function.

    Science.gov (United States)

    Rodrigues, Stephen F; Granger, D Neil

    2015-01-01

    The barrier properties of endothelial cells are critical for the maintenance of water and protein balance between the intravascular and extravascular compartments. An impairment of endothelial barrier function has been implicated in the genesis and/or progression of a variety of pathological conditions, including pulmonary edema, ischemic stroke, neurodegenerative disorders, angioedema, sepsis and cancer. The altered barrier function in these conditions is often linked to the release of soluble mediators from resident cells (e.g., mast cells, macrophages) and/or recruited blood cells. The interaction of the mediators with receptors expressed on the surface of endothelial cells diminishes barrier function either by altering the expression of adhesive proteins in the inter-endothelial junctions, by altering the organization of the cytoskeleton, or both. Reactive oxygen species (ROS), proteolytic enzymes (e.g., matrix metalloproteinase, elastase), oncostatin M, and VEGF are part of a long list of mediators that have been implicated in endothelial barrier failure. In this review, we address the role of blood borne cells, including, neutrophils, lymphocytes, monocytes, and platelets, in the regulation of endothelial barrier function in health and disease. Attention is also devoted to new targets for therapeutic intervention in disease states with morbidity and mortality related to endothelial barrier dysfunction. PMID:25838983

  9. Numerical simulations of capillary barrier field tests

    International Nuclear Information System (INIS)

    Numerical simulations of two capillary barrier systems tested in the field were conducted to determine if an unsaturated flow model could accurately represent the observed results. The field data was collected from two 7-m long, 1.2-m thick capillary barriers built on a 10% grade that were being tested to investigate their ability to laterally divert water downslope. One system had a homogeneous fine layer, while the fine soil of the second barrier was layered to increase its ability to laterally divert infiltrating moisture. The barriers were subjected first to constant infiltration while minimizing evaporative losses and then were exposed to ambient conditions. The continuous infiltration period of the field tests for the two barrier systems was modelled to determine the ability of an existing code to accurately represent capillary barrier behavior embodied in these two designs. Differences between the field test and the model data were found, but in general the simulations appeared to adequately reproduce the response of the test systems. Accounting for moisture retention hysteresis in the layered system will potentially lead to more accurate modelling results and is likely to be important when developing reasonable predictions of capillary barrier behavior

  10. Modeling and Simulation of Long-Term Performance of Near-Surface Barriers

    Energy Technology Data Exchange (ETDEWEB)

    Piet, S. J.; Jacobson, J. J.; Martian, P.; Martineau, R.; Soto, R.

    2003-02-25

    Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone's back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surface water. The design lifespan for such barriers ranges from 30 to 1000 years, depending on hazard and regulations. In light of historical performance, society needs a better basis for predicting barrier performance over long time periods and tools for optimizing maintenance of barriers while in service. We believe that, as in other industries, better understanding of the dynamics of barrier system degradation will enable improved barriers (cheaper, longer-lived, simpler, easier to maintain) and improved maintenance. We are focusing our research on earthen caps, especially those with evapo-transpiration and capillary breaks. Typical cap assessments treat the barrier's structure as static prior to some defined lifetime. Environmental boundary conditions such as precipitation and temperature are treated as time dependent. However, other key elements of the barrier system are regarded as constant, including engineered inputs (e.g., fire management strategy, irrigation, vegetation control), surface ecology (critical to assessment of plant transpiration), capillary break interface, material properties, surface erosion rate, etc. Further, to be conservative, only harmful processes are typically considered. A more holistic examination of both harmful and beneficial processes will provide more realistic pre-service prediction and in-service assessment of performance as well as provide designers a tool to encourage beneficial processes while discouraging harmful processes

  11. Modeling and Simulation of Long-Term Performance of Near-Surface Barriers

    International Nuclear Information System (INIS)

    Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone's back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surface water. The design lifespan for such barriers ranges from 30 to 1000 years, depending on hazard and regulations. In light of historical performance, society needs a better basis for predicting barrier performance over long time periods and tools for optimizing maintenance of barriers while in service. We believe that, as in other industries, better understanding of the dynamics of barrier system degradation will enable improved barriers (cheaper, longer-lived, simpler, easier to maintain) and improved maintenance. We are focusing our research on earthen caps, especially those with evapo-transpiration and capillary breaks. Typical cap assessments treat the barrier's structure as static prior to some defined lifetime. Environmental boundary conditions such as precipitation and temperature are treated as time dependent. However, other key elements of the barrier system are regarded as constant, including engineered inputs (e.g., fire management strategy, irrigation, vegetation control), surface ecology (critical to assessment of plant transpiration), capillary break interface, material properties, surface erosion rate, etc. Further, to be conservative, only harmful processes are typically considered. A more holistic examination of both harmful and beneficial processes will provide more realistic pre-service prediction and in-service assessment of performance as well as provide designers a tool to encourage beneficial processes while discouraging harmful processes. Thus, the

  12. Continuous Spontaneous Alternation and Turn Alternation in Artemia sp.

    OpenAIRE

    Çarkoğlu, Can; Yılmaz, Meltem; Balcı, Fuat

    2015-01-01

    Free-running spontaneous alternation refers to the animal’s tendency to prefer the least recently visited locations in successive spatial choices, which is attributed to the animals’ choice between stimuli based on prior experience.  Turn alternation, which is observed in directional choices preceded by a forced turn in one direction, also reflects the animals’ tendency to alternate between directional choices but this tendency has been assumed to rely on other cues (e.g., proprioceptive cues...

  13. Landfill Barrier-Overview and Prospect

    Institute of Scientific and Technical Information of China (English)

    Zheng Liange; Zhao Yongsheng

    2000-01-01

    Landfill is the primary method of waste disposal. The increasing attention focused on the effect of landfill on environment prompts the development of environmental sound landfill system. As the key parts of landfill, the barrier system can provide impermeabilization of leachate and prevent biogas from escaping intotheenvironment. In recent years, the technology pertaining the barrier system developed rapidly. In this paper, new materials used in liners and new concept of barrier construction are reviewed; the mechanisms of leachate through clay liner and geomembrane, the calculation of leaks through liner and the effect of freezing/thaw on liner are discussed.

  14. Development of dielectric-barrier-discharge ionization.

    Science.gov (United States)

    Guo, Cheng'an; Tang, Fei; Chen, Jin; Wang, Xiaohao; Zhang, Sichun; Zhang, Xinrong

    2015-03-01

    Dielectric-barrier-discharge ionization is an ambient-ionization technique. Since its first description in 2007, it has attracted much attention in such fields as biological analysis, food safety, mass-spectrometry imaging, forensic identification, and reaction monitoring for its advantages, e.g., low energy consumption, solvent-free method, and easy miniaturization. In this review a brief introduction to dielectric barrier discharge is provided, and then a detailed introduction to the dielectric-barrier-discharge-ionization technique is given, including instrumentation, applications, and mechanistic studies. Based on the summary of reported work, possible future uses of this type of ionization source are discussed at the end. PMID:25510973

  15. Performance modelling of barriers: A pragmatic approach

    International Nuclear Information System (INIS)

    In this article physical barriers to control migration of contaminants from abandoned nuclear sites are discussed. Modelling the performance and time behaviour of barriers against release and transport of radionuclides is difficult. Analysis of the long-term performance poses problems since the properties of the barrier may change in time. Due to the complexity of possible degradation processes, the few available data are highly empirical, making the prediction of the degradation as a function of time almost impossible. Our main objective was to find a model that is relatively easy to use and that can give results adequate for long-term radiological assessments

  16. Cultural Barriers to International Business Negotiations

    Institute of Scientific and Technical Information of China (English)

    刘竹林; 王俊

    2013-01-01

    Studies in international business negotiation acquire unprecedented significance, as globalization closely connects vari⁃ous business fields into a dynamic whole. Cultural factors play a vital role in international business negotiation. This paper begins with a brief introduction to business negotiation, international business negotiation and significance of cultural barriers to interna⁃tional business negotiation. It then explores two fundamental cultural differences of China and western countries:value differenc⁃es and thinking-pattern differences, which pose cultural barriers. The author then puts forward three strategies to help remove the cultural barriers and achieve successful negotiations.

  17. The nuclear power alternative

    International Nuclear Information System (INIS)

    The Director General of the IAEA stressed the need for energy policies and other measures which would help to slow and eventually halt the present build-up of carbon dioxide, methane and other so-called greenhouse gases, which are held to cause global warming. He urged that nuclear power and various other sources of energy, none of which contribute to global warming, should not be seen as alternatives, but should all be used to counteract the greenhouse effect. He pointed out that the commercially used renewable energies, apart from hydropower, currently represent only 0.3% of the world's energy consumption and, by contrast, the 5% of the world's energy consumption coming from nuclear power is not insignificant. Dr. Blix noted that opposition for nuclear power stems from fear of accidents and concern about the nuclear wastes. But no generation of electricity, whether by coal, hydro, gas or nuclear power, is without some risk. He emphasized that safety can never be a static concept, and that many new measures are being taken by governments and by the IAEA to further strengthen the safety of nuclear power

  18. State of knowledge on nuclear waste in 2011 - the geology, barriers, options; Kunskapslaeget paa kaernavfallsomraadet 2011 - geologin, barriaererna, alternativen

    Energy Technology Data Exchange (ETDEWEB)

    2011-02-15

    This year's state of knowledge report highlights the geological conditions for SKB's site selection, follows last year's theme on the engineered barriers (copper canister and the buffer), and highlights the alternative question from a legal, technical and social science perspective

  19. An Aluminum Magnesium Hydroxide Stearate-based Skin Barrier Protection Cream Used for the Management of Eczematous Dermatitis

    Science.gov (United States)

    Bhambri, Sanjay; Michaels, Brent

    2008-01-01

    Eczematous dermatoses can often be very difficult to treat. An aluminum magnesium hydroxide stearate-based cream has recently become available for clinical use. Aluminum magnesium hydroxide stearate-based cream provides an alternative option in treating these dermatoses while providing barrier protection against external allergens and irritants. This article reviews various studies evaluating aluminum magnesium hydroxide stearate-based cream. PMID:21212843

  20. As-Al recoil implantation through Si 3N 4 barrier layer

    Science.gov (United States)

    Godignon, P.; Morvan, E.; Montserrat, J.; Jordà, X.; Flores, D.; Rebollo, J.

    1999-01-01

    Al recoil implantation have been shown to be a possible alternative to direct Al ion implantation to avoid usual problems linked with Al sources. Poor efficiency of the recoil + annealing process is observed if no barrier or an oxyde screen layers are used. This problem can be solved using a Si 3N 4 screen layer. Then, P-N and N +/P/N structures can be obtained with deep low doped P-well with reduced thermal budget.

  1. As-Al recoil implantation through Si3N4 barrier layer

    International Nuclear Information System (INIS)

    Al recoil implantation have been shown to be a possible alternative to direct Al ion implantation to avoid usual problems linked with Al sources. Poor efficiency of the recoil + annealing process is observed if no barrier or an oxyde screen layers are used. This problem can be solved using a Si3N4 screen layer. Then, P-N and N+/P/N structures can be obtained with deep low doped P-well with reduced thermal budget

  2. Cancer-related electronic support groups as navigation-aids: Overcoming geographic barriers

    OpenAIRE

    Till, James E

    2004-01-01

    Cancer-related electronic support groups (ESGs) may be regarded as a complement to face-to-face groups when the latter are available, and as an alternative when they are not. Advantages over face-to-face groups include an absence of barriers imposed by geographic location, opportunities for anonymity that permit sensitive issues to be discussed, and opportunities to find peers online. ESGs can be especially valuable as navigation aids for those trying to find a way through the healthcare syst...

  3. Numerical simulations of superlattice patterns in dielectric barrier discharges at atmospheric pressure

    Science.gov (United States)

    Liu, Fucheng; Wang, Xiaofei; He, Yafeng; Dong, Lifang

    2016-03-01

    This paper presents the numerical investigation on superlattice patterns in atmospheric pressure glow discharges in dielectric barrier discharges by using a self-consistent 2D fluid model. It is found that the superlattice pattern is an interleaving of two filamentary sub-patterns with alternate spatial and temporal characteristics. The competition between the volume ionization and the memory effects of both surface charges and space charges is expected to the formation mechanism of this superlattice pattern.

  4. Antimicrobial, Physicochemical, Mechanical, and Barrier Properties of Tapioca Starch Films Incorporated with Eucalyptus Extract

    OpenAIRE

    M. Rojhan; Nouri, L.

    2013-01-01

    Starch is found in abundance in nature and it is one of the raw materials used for food packagingbecause of the low price, biodegradability, good mechanical and barrier properties. The recycling ability ofcoating materials was significantly increased by using edible films and coating in comparison to traditionalpackaging and it could be an alternative for synthetic films. In this research, the effect of eucalyptus extract(Aqueous Extract) was investigated on tapioca starch films. Tapioca star...

  5. Stochastic Spot/Volatility Correlation in Stochastic Volatility Models and Barrier Option Pricing

    OpenAIRE

    Mark Higgins

    2014-01-01

    Most models for barrier pricing are designed to let a market maker tune the model-implied covariance between moves in the asset spot price and moves in the implied volatility skew. This is often implemented with a local volatility/stochastic volatility mixture model, where the mixture parameter tunes that covariance. This paper defines an alternate model where the spot/volatility correlation is a separate mean-reverting stochastic variable which is itself correlated with spot. We also develop...

  6. A brief sexual barrier intervention for women living with AIDS: Acceptability, use, and ethnicity

    OpenAIRE

    Jones, Deborah L; Weiss, Stephen M; Malow, Robert; ISHII, MARY; Devieux, Jessy; Stanley, Heidi; Cassells, Andrea; Tobin, Jonathan N.; Brondolo, Elizabeth; LaPerriere, Arthur; Efantis-Potter, Jonell; O'Sullivan, Mary Jo; Schneiderman, Neil

    2001-01-01

    Interventions aimed at reducing sexual transmission of human immunodeficiency virus/sexually transmitted diseases (HIV/STDs) have focused primarily on male condom use among seronegative men and women. However, female-controlled sexual barriers (female condoms and vaginal microbicides) offer women living with acquired immunodeficiency syndrome (AIDS) alternative methods to protect themselves and others from disease transmission. A pilot behavioral intervention was conducted to increase sexual ...

  7. Effect of Dielectric and Liquid on Plasma Sterilization Using Dielectric Barrier Discharge Plasma

    OpenAIRE

    Mastanaiah, Navya; Johnson, Judith A.; Roy, Subrata

    2013-01-01

    Plasma sterilization offers a faster, less toxic and versatile alternative to conventional sterilization methods. Using a relatively small, low temperature, atmospheric, dielectric barrier discharge surface plasma generator, we achieved ≥6 log reduction in concentration of vegetative bacterial and yeast cells within 4 minutes and ≥6 log reduction of Geobacillus stearothermophilus spores within 20 minutes. Plasma sterilization is influenced by a wide variety of factors. Two factors studied in ...

  8. 10 Years-Activities at ONERA on Advanced Thermal Barrier Coatings

    OpenAIRE

    Bacos, M. P; Dorvaux, J.M.; Landais, S.; Lavigne, O.; Mévrel, R.; M. Poulain; Rio, C; Vidal-Sétif, M.H.

    2011-01-01

    Developing thermal barrier coatings operating at higher temperature and/or for very long durations (commercial aircraft applications) is one of the technological and economical challenges for engine manufacturers. This includes the search for (i) low thermal conductivity, high thermal stability and CMAS resistant ceramic top coat, and (ii) alternative low cost bond coat with improved oxidation resistance and chemical compatibility with the substrate. This paper reviews the rationale sustainin...

  9. UNJUK KERJA REAKTOR PLASMA DIELECTRIC BARRIER DISCHARGE UNTUK PRODUKSI BIODIESEL DARI MINYAK KELAPA SAWIT

    OpenAIRE

    Ardian Dwi Yudhistira; Istadi Istadi

    2013-01-01

    Biodiesel is one of alternative renewable energy source to substitute diesel fuel. Various biodiesel productionprocesses through transesterification reaction with a variety of catalysts have been developed by previousresearcher. This process still has the disadvantage of a long reaction time, and high energy need. DielectricBarrier Discharge (DBD) plasma electro-catalysis may become a solution to overcome the drawbacks in theconventional transesterification process. This process only needs a ...

  10. Barriers to Curricular Change in General Education Mathematics at a Large Public Institution

    OpenAIRE

    Jorgensen, Marcus

    2014-01-01

    This qualitative study looked for barriers to curricular change in general education mathematics at a large public university (LPU) in the Western United States. The literature showed that a number of national organizations dealing in math education have recommended alternatives to the traditional algebra-intensive curriculum. LPU still relies predominantly on traditional College Algebra as its quantitative literacy (QL) course. With such an algebra-heavy emphasis, students may be missing mor...

  11. Feasibility of permeation grouting for constructing subsurface barriers

    International Nuclear Information System (INIS)

    Efforts are being made to devise technologies that provide interim containment of waste sites while final remediation alternatives are developed. Permeation grouting, a technique used extensively in the civil and mining engineering industry has been investigated as a method for emplacing a subsurface containment barrier beneath existing waste sites. Conceptually an underlying barrier is placed by injecting grout into the formation at less than fracturing pressure from a series of directionally drilled boreholes beneath the waste site. This study evaluated the penetration and performance characteristics in varying soil conditions of four different grout materials (two microfine cements, mineral wax, and sodium silicate) at a field scale. Field testing consisted of grout injection via sleeve (tube-a'-manchette) pipe into both vertical and horizontal borehole configurations at the Mixed Waste Landfill Integrated Demonstration site at Sandia National Laboratories. Prior to, during, and after grout injection non-intrusive geophysical techniques were used to map grout flow. Following the tests, the site was excavated to reveal details of the grout permeation, and grouted soil samples were cored for laboratory characterization. The non-intrusive and intrusive grout mapping showed preferential flow patterns, i.e., the grout tended to follow the path of least resistance. Preliminary testing indicates that permeation grouting is a feasible method for emplacing a low permeability subsurface barrier in the semi-arid unconsolidated alluvial soils common to the Southwest. Despite the success of this project, difficulties in predicting grout flow in heterogeneous soils and non-intrusive methods for imaging grout location and continuity are issues that need more attention

  12. A capillary network model for gas migration in engineered barriers

    International Nuclear Information System (INIS)

    Gas may be generated in a waste repository by a number of mechanisms, including anaerobic corrosion of metals and microbial degradation. Scoping calculations indicate that a free gas phase will probably form. Here attention is focused on two hazards this may pose. First, a gas pressure buildup may damage engineered barriers. Second, migrating gas may displace contaminated pore water. In previous studies, Darcy two-phase flow models have been used to calculate gas pressures and pore water displacement. A two-dimensional capillary network model has been developed and implemented in a numerical code, GARNET. Example calculations of the migration of gas from a point source have been undertaken to demonstrate its functionality and to indicate how phenomena, such as intermittent gas fluxes, may be modelled. Results indicate that the capillary network model reproduces behaviour observed in gas migration through low permeability media, and is a viable alternative to Darcy two-phase flow models

  13. Staff resistance to restraint reduction: identifying & overcoming barriers.

    Science.gov (United States)

    Curran, Staci Silver

    2007-05-01

    Professional organizations, regulating agencies, and hospital administrators have taken a strong stance on restraint reduction policies. When implementing a restraint reduction initiative, it is important to identify the barriers to restraint reduction, such as concern for personal safety, lack of knowledge about and practice using alternate de-escalation skills, and fear of disrupting the therapeutic milieu by using a variety of de-escalation methods. Education aimed to reduce the use of restraints needs to do more than simply provide information. It is important to acknowledge the emotional response of the nursing staff and the culture of the current practice. A variety of educational strategies, including role-playing, and case studies will help identify attitudes, beliefs, and behaviors that are congruent with reducing the use of restraints. If the ultimate goal of restraint reduction is philosophical change, it will eventually lead to a new culture of practice. PMID:17526330

  14. The cervical cap: a barrier contraceptive.

    Science.gov (United States)

    Hastings-Tolsma, M T

    1982-01-01

    The cervical cap may eventually prove to be a safe, satisfactory, noninvasive, and nonhormonal contraceptive alternative for women in the US. The cap is currently approved for investigational use only, and is available from a limited number of providers. The Prentif cavity rim cap is the most commonly used and is available in 4 sizes. The soft rubber device is thimble shaped, approximately 1 1/4 inches long, with a narrow groove along the inner surface that creates a suction seal when fitted over the cervix. The inability to match cap and cervical circumferences precisely is a recognized drawback. Theoretically, the cap alone should prevent sperm entry into the uterus, however, the use of a spermicide placed in the dome before insertion is recommended. The cap's effectiveness is not yet documented. Estimates from a 1953 study of 143 users were 92.4/100 women years of use for use effectiveness, and the theoretical effectiveness is believed to be more than 98%. Failures with the cap may result from a variety of reasons, particularly dislodgement. The advantage of the cap over other barrier methods is that it can be inserted any time prior to intercourse and left in place longer. The ideal safety period for placement has not been validated, but a range of 1-7 days has been recommended. The length of time the spermicide remains effective and the cervical effects of prolonged contact are of prime concern. The cap may be used by some women who cannot be properly fitted for a diaphragm due to vaginal or uterine anomalies. Sexual arousal and orgasmic response are reported by some cap users to be more pleasurable with the cap than with the diaphragm. Reported problems with use include discomfort during intercourse and improper fit during some days of the menstrual cycle. Contraindications for use include cervical inconsistencies, infection, allergy to the spermicide or the rubber, and inability to learn proper insertion and removal techniques. Insertion and removal may be

  15. Alternative Genres of IS Research

    DEFF Research Database (Denmark)

    Avital, Michel; Mathiassen, Lars; Crowston, Kevin;

    2012-01-01

    perspectives, research methods, semantic framing, literary styles, and media of expression. Overall, the application of alternative genres is considered to be a generative act that provides an opportunity to take a fresh look and to gain deeper understanding of the subject matter. Nonetheless, paradoxically......The potential value of alternative genres in IS research is the core question that drives this panel discussion. The term “Alternative Genres” refers to unconventional forms of thinking, doing, and communicating scholarship and practice. It relates to innovation with respect to epistemological...... the prevailing genres have much inertia, in spite of the inherent boundary spanning nature of alternative genres. Building on their own recent empirical research, the panelists will debate the potential value of alternative genres as unconventional modality of IS scholarship and how alternative genres...

  16. Application of dielectric surface barrier discharge for food storage

    Directory of Open Access Journals (Sweden)

    Yassine BELLEBNA

    2015-12-01

    Full Text Available Ozone (O3 is a powerful oxidizer and has much higher disinfection potential than chlorine and other disinfectants. Ozone finds its application mainly in water treatment and air purification Dielectric barrier discharge (DBD method has proved to be the best method to produce ozone. Dried air or oxygen is forced to pass through a 1-2 mm gap. The aim of this study was to show that disinfection system using ozone generated by dielectric barrier discharge (DBD is an effective alternative to be used in food industry and ensures a safe quality of air for optimum preservation of fruits and vegetables. The DBDs are specific kind of discharges because one (or sometimes both electrodes is covered by a dielectric material, thereby preventing the discharge to move towards electrical breakdown. A succession of microdischarges occurs rapidly; their "lifetime" is in the range of a few nanoseconds. One of their most important applications is the production of ozone for air treatment, used mainly in the area of food industry, for extending the storage life of foods. After the achievement of a surface DBD reactor of cylindrical shape and its electrical characterization, it was then used as an ozone generator for air disinfection. Obtained results have shown that this reactor used as an ozone generator is effective for disinfection of air by removing viruses, bacteria and pathogens, causing the slowdown of the ripening process of fruits and vegetables.

  17. Engineered barrier durability: An issue for disposal near populated areas

    International Nuclear Information System (INIS)

    Under the current national policy for disposal of low-level radioactive waste (LLW) in the United States of America, each State is required to provide disposal capacity for the LLW generated within its borders. The formation of ''Compacts'' of several States is allowed if approved by Congress. Such forced regionalization of disposal facilities based on State boundaries results in some disposal facilities being sited near populated areas at locations with less than optimum site characteristics from a disposal standpoint. To compensate for this engineered barriers are included in the proposed designs. Portland cement based concrete (PCC), which is the dominant material for disposal vault designs, is degraded via many mechanisms, most of which are related to its permeability. The numerous uncertainties associated with the long-term performance of PCC has lead to many unsuccessful attempts to obtain public acceptance of proposed disposal facilities. These unsuccessful efforts have delayed establishing disposal capacity to the point that a crisis is looming on the horizon. This paper investigates the results of on-going research into the viability of commercially available, impermeable, mass-poured construction materials as an alternative to PCC in LLW disposal vaults. The results from testing and research on two such materials, concrete made from sulfur polymer cement (SPC) and ICOM (an epoxy based concrete) are reported. Material properties and test results include strength parameters, chemical resistance, porosity, permeability, deconability, radiation damage resistance, and biodegradation. The data indicates that with these alternative materials the uncertainties in predicting service life of an engineered barrier can be reduced

  18. Economic and other barriers to adopting recommendations to prevent childhood obesity: results of a focus group study with parents

    Directory of Open Access Journals (Sweden)

    Taveras Elsie M

    2009-12-01

    Full Text Available Abstract Background Parents are integral to the implementation of obesity prevention and management recommendations for children. Exploration of barriers to and facilitators of parental decisions to adopt obesity prevention recommendations will inform future efforts to reduce childhood obesity. Methods We conducted 4 focus groups (2 English, 2 Spanish among a total of 19 parents of overweight (BMI ≥ 85th percentile children aged 5-17 years. The main discussion focused on 7 common obesity prevention recommendations: reducing television (TV watching, removing TV from child's bedroom, increasing physically active games, participating in community or school-based athletics, walking to school, walking more in general, and eating less fast food. Parents were asked to discuss what factors would make each recommendation more difficult (barriers or easier (facilitators to follow. Participants were also asked about the relative importance of economic (time and dollar costs/savings barriers and facilitators if these were not brought into the discussion unprompted. Results Parents identified many barriers but few facilitators to adopting obesity prevention recommendations for their children. Members of all groups identified economic barriers (time and dollar costs among a variety of pertinent barriers, although the discussion of dollar costs often required prompting. Parents cited other barriers including child preference, difficulty with changing habits, lack of information, lack of transportation, difficulty with monitoring child behavior, need for assistance from family members, parity with other family members, and neighborhood walking safety. Facilitators identified included access to physical activity programs, availability of alternatives to fast food and TV which are acceptable to the child, enlisting outside support, dietary information, involving the child, setting limits, making behavior changes gradually, and parental change in shopping

  19. Krypton control alternatives

    International Nuclear Information System (INIS)

    A reprocessing plant for 350 metric tons per year LWR spent fuel cooled for at least 7 years is planned in the FRG. A routine Kr-85 retention for radiation protection reasons is not demanded by the German reactor safety and radiation management technology for larger plants in the future. The licensing authorities also do not require a routine Kr-85 retention at the plant site. Technical and safety characteristics of various Kr-85 removal processes are described and compared, including the precleaning steps in an integrated dissolver off-gas system. The interactions with subsequent conditioning and storage of Kr and with process modifications in the plant headend are also taken into account. A commercial use of the inactive Xe and part of the Kr-85 may have an influence on a cost-benefit analysis and the selection of a removal process. Two alternative processes are being developed on an engineering scale. A cryogenic distillation process using an O2-free off-gas is under investigation on a pilot plant scale since 1976. A selective absorption process using freon-12 at low temperatures and at atmospheric pressure has been investigated at the laboratory scale since 1980. Test operation on an engineering scale started late in 1983. Essential results and operating experiences with both facilities are summarized. Technical as well as safety aspects are in favor of the selective absorption process. A final decision on what process will be used in the future shall be made as soon as comparable technical experiences from both processes are available

  20. Tsunami wave suppression using submarine barriers

    Energy Technology Data Exchange (ETDEWEB)

    Fridman, Aleksei M [Russian Research Centre ' Kurchatov Institute' , Moscow (Russian Federation); Alperovich, Leonid S; Pustil' nik, Lev A; Shtivelman, D [Department of Geophysics and Planetary Sciences, Tel-Aviv University (Israel); Shemer, L; Liberzon, D [School of Mechanical Engineering, Tel-Aviv University (Israel); Marchuk, An G [Institute of Computational Mathematics and Mathematical Geophysics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2010-11-15

    Submerged barriers, single or double, can be used to greatly reduce the devastating effect of a tsunami wave according to a research flume study conducted at Tel Aviv University. (instruments and methods of investigation)

  1. ULTRA BARRIER TOPSHEET (UBT) FOR FLEXIBLE PHOTOVOLTAICS

    Energy Technology Data Exchange (ETDEWEB)

    DeScioli, Derek

    2013-06-01

    This slide-show presents 3M photovoltaic-related products, particularly flexible components. Emphasis is on the 3M Ultra Barrier Solar Films. Topics covered include reliability and qualification testing and flexible photovoltaic encapsulation costs.

  2. Barrier Li Quantum Dots in Magnetic Fields

    Institute of Scientific and Technical Information of China (English)

    LIU Yi-Min; LI Xiao-Zhu; YAN Wen-Hong; BAO Cheng-Guang

    2003-01-01

    The methods for the few-body system are introduced to investigate the states of the barrier Li quantumdots (QDs) in an arbitrary strength of magnetic field. The configuration, which consists of a positive ion located on thez-axis at a distance d from the two-dimensional QD plane (the x-y plane) and three electrons in the dot plane boundby the positive ion, is called a barrier Li center. The system, which consists of three electrons in the dot plane bound bythe ion, is called a barrier Li QD. The dependence of energy of the state of the barrier Li QD on an external magneticfield B and the distance d is obtained. The angular momentum L of the ground states is found to jump not only withthe variation of B but also with d.

  3. Vapor-barrier Vacuum Isolation System

    Science.gov (United States)

    Weinstein, Leonard M. (Inventor); Taminger, Karen M. (Inventor)

    2014-01-01

    A system includes a collimated beam source within a vacuum chamber, a condensable barrier gas, cooling material, a pump, and isolation chambers cooled by the cooling material to condense the barrier gas. Pressure levels of each isolation chamber are substantially greater than in the vacuum chamber. Coaxially-aligned orifices connect a working chamber, the isolation chambers, and the vacuum chamber. The pump evacuates uncondensed barrier gas. The barrier gas blocks entry of atmospheric vapor from the working chamber into the isolation chambers, and undergoes supersonic flow expansion upon entering each isolation chamber. A method includes connecting the isolation chambers to the vacuum chamber, directing vapor to a boundary with the working chamber, and supersonically expanding the vapor as it enters the isolation chambers via the orifices. The vapor condenses in each isolation chamber using the cooling material, and uncondensed vapor is pumped out of the isolation chambers via the pump.

  4. Barrier Li Quantum Dots in Magnetic Fields

    Institute of Scientific and Technical Information of China (English)

    LIUYi-Min; LIXiao-Zhu; YANWen-Hong; BAOCheng-Guang

    2003-01-01

    The methods for the few-body system are introduced to investigate the states of the barrier Li quantum dots (QDs) in an arbitrary strength of magnetic field. The configuration, which consists of a positive ion located on the z-axis at a distaneed from the two-dimensional QD plane (the x-y plane) and three electrons in the dot plane bound by the positive ion, is called a barrier Li center. The system, which consists of three electrons in the dot plane bound by the ion,is called a barrier Li QD. The dependence of energy of the state of the barrier Li QD on an external magnetic field B and the distance d is obtained. The angular momentum L of the ground states is found to jump not only with the variation orB but also with d.

  5. Mucus as a Barrier to Drug Delivery

    DEFF Research Database (Denmark)

    Bøgh, Marie; Nielsen, Hanne Mørck

    2015-01-01

    Viscoelastic mucus lines all mucosal surfaces of the body and forms a potential barrier to mucosal drug delivery. Mucus is mainly composed of water and mucins; high-molecular weight glycoproteins forming an entangled network. Consequently, mucus forms a steric barrier and due to its negative charge...... complex gel barrier to drug delivery. Current knowledge of mucus characteristics and barrier properties, as achieved by state-of-the-art methodologies, is the topic of this MiniReview emphasizing the gastrointestinal mucus and an overall focus on oral drug delivery. Cell culture-based in vitro models are...... well-established as essential tools in drug research and development, but traditionally, mucus-containing models have only rarely been applied. However, a number of mucus-containing in vitro models have recently been described in the literature and their properties and applications will be reviewed and...

  6. On the Existence of Compositional Barrier Certificates

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Wisniewski, Rafael; Pappas, George J.

    2012-01-01

    This paper provides a necessary and sufficient condition for the compositional verification of a continuous system with additively separable barrier functions. The compositional safety verification enables the verification of an interconnection of subsystems. The idea behind the compositional ana...

  7. Tantalum oxide barrier in magnetic tunnel junctions

    Institute of Scientific and Technical Information of China (English)

    Guanghua Yu; Tingting Ren; Wei Ji; Jiao Teng; Fengwu Zhu

    2004-01-01

    Tantalum as an insulating barrier can take the place of Al in magnetic tunnel junctions (MTJs). Ta barriers in MTJs were fabricated by natural oxidation. X-ray photoelectron spectroscopy (XPS) was used to characterize the oxidation states of Ta barrier.The experimental results show that the chemical state of tantalum is pure Ta5+ and the thickness of the oxide is 1.3 nm. The unoxidized Ta in the barrier may chemically reacted with NiFe layer which is usually used in MTJs to form an intermetallic compound,NiTa2. A magnetic "dead layer" could be produced in the NiFe/Ta interface. The "dead layer" is likely to influence the spinning electron transport and the magnetoresistance effect.

  8. Evapotranspiration studies for protective barriers: Experimental plans

    International Nuclear Information System (INIS)

    This document describes a general theory and experimental plans for predicting evapotranspiration in support of the Protective Barrier Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. 45 refs., 1 fig., 4 tabs

  9. Markers for blood-brain barrier integrity

    DEFF Research Database (Denmark)

    Saunders, Norman R; Dziegielewska, Katarzyna M; Møllgård, Kjeld;

    2015-01-01

    In recent years there has been a resurgence of interest in brain barriers and various roles their intrinsic mechanisms may play in neurological disorders. Such studies require suitable models and markers to demonstrate integrity and functional changes at the interfaces between blood, brain, and...... cerebrospinal fluid. Studies of brain barrier mechanisms and measurements of plasma volume using dyes have a long-standing history, dating back to the late nineteenth-century. Their use in blood-brain barrier studies continues in spite of their known serious limitations in in vivo applications. These were well...... known when first introduced, but seem to have been forgotten since. Understanding these limitations is important because Evans blue is still the most commonly used marker of brain barrier integrity and those using it seem oblivious to problems arising from its in vivo application. The introduction of...

  10. JET internal transport barriers: experiment vs theory

    International Nuclear Information System (INIS)

    A large variety of JET discharges with internal transport barriers (ITBs) has been analysed in order to determine the main features which characterize turbulence stabilization at the barrier. It is found that the location of barriers is well correlated with regions where the ExB flow shearing rate exceeds the linear growth rate of the ion temperature gradient mode instability (γηi). A key point is the dependence of γηi on the magnetic shear: in the discharges of this database the reduction of γηi associated to very low or null magnetic shear favours the formation of an ITB. After the ITB formation a positive feedback occurs in which the ExB flow shear mechanism has the leading role and the position of the barrier may be no longer linked to the low shear region

  11. Tsunami wave suppression using submarine barriers

    International Nuclear Information System (INIS)

    Submerged barriers, single or double, can be used to greatly reduce the devastating effect of a tsunami wave according to a research flume study conducted at Tel Aviv University. (instruments and methods of investigation)

  12. Communicating across barriers at home and abroad

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, J.W.

    1985-01-01

    This paper intends to catalyze the exchange of experience among technical communicators in meeting the challenge of communicating across a multitude of barriers: linguistic, disciplinary, cultural, political, intellectual, and emotional.

  13. Resilient thermal barrier for high temperatures

    Science.gov (United States)

    Frye, J. A.

    1977-01-01

    Abrasion-resistant thermal barrier, consisting of two layers of woven fabric or braided sleeving with bulk insulation sandwiched between, shows excellent resilience even after compression at temperatures above 980C.

  14. Electron tunneling across a tunable potential barrier

    International Nuclear Information System (INIS)

    We present an experiment where the elementary quantum electron tunneling process should be affected by an independent gate voltage parameter. We have realized nanotransistors where the source and drain electrodes are created by electromigration inducing a nanometer sized gap acting as a tunnel barrier. The barrier potential shape is in first approximation considered trapezoidal. The application of a voltage to the gate electrode close to the barrier region can in principle affect the barrier shape. Simulations of the source drain tunnel current as a function of the gate voltage predict modulations as large as one hundred percent. The difficulty of observing the predicted behaviour in our samples might be due to the peculiar geometry of the realized tunnel junction.

  15. Electrolyte diffusion in compacted montmorillonite engineered barriers

    International Nuclear Information System (INIS)

    The bentonite-based engineered barrier or packing is a proposed component of several designs conceived to dispose of high-level nuclear waste in geologic repositories. Once radionuclides escape the waste package, they must first diffuse through the highly impermeable clay-rich barrier before they reach the host repository. To determine the effectiveness of the packing as a sorption barrier in the transient release period and as a mass-transfer barrier in the steady release period over the geologic time scales involved in nuclear-waste disposal, a fundamental understanding of the diffusion of electrolytes in compacted clays is required. The authors present, and compare with laboratory data, a model quantifying the diffusion rates of cationic cesium and uncharged tritium in compacted montimorillonite clay

  16. Headwater Stream Barriers in Western Oregon

    Data.gov (United States)

    Oak Ridge National Laboratory — This data set is an ArcInfo point coverage depicting barriers to fish migration in headwater basins in western Oregon. Data were compiled from reports by fisheries...

  17. Barrier Cavities in the Brookhaven AGS

    International Nuclear Information System (INIS)

    In collaboration with KEK two barrier cavities, each generating 40 kV per turn have been installed in the Brookhaven AGS. Machine studies are described and their implications for high intensity operations are discussed

  18. Alternative fuelds in urban fleets

    International Nuclear Information System (INIS)

    In this presentation the author addresses four main objectives. They are to: discuss programs that are driving the introduction of alternative fuels into fleet operations in urban areas around the country; define alternative fuels; quantify the present use and future projections on alternative fuel vehicles (AVFs) in the Chicago metropolitan statistical area; and discuss benefits of increased use of alternative fuels in urban areas. Factors which touch on these points include: present domestic dependence on petroleum for autos, with usage exceeding production; the large populations in urban areas which do not meet Clean Air Standards; recent legislative initiatives which give guidance and aid in the adoption of such strategies

  19. Alternative fuelds in urban fleets

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, T.

    1994-12-31

    In this presentation the author addresses four main objectives. They are to: discuss programs that are driving the introduction of alternative fuels into fleet operations in urban areas around the country; define alternative fuels; quantify the present use and future projections on alternative fuel vehicles (AVFs) in the Chicago metropolitan statistical area; and discuss benefits of increased use of alternative fuels in urban areas. Factors which touch on these points include: present domestic dependence on petroleum for autos, with usage exceeding production; the large populations in urban areas which do not meet Clean Air Standards; recent legislative initiatives which give guidance and aid in the adoption of such strategies.

  20. Use of element model to evaluate transmissibility reduction due to barriers

    Energy Technology Data Exchange (ETDEWEB)

    Svanes, T.; South, D.; Dronen, O.M. [Statoil, Bergen (Norway)

    1997-08-01

    Water breakthrough has been observed a year earlier than expected in the productive Oseberg Formation in the Veslefrikk Field. Production data revealed extensive water override, whereas the opposite situation was expected based on a homogeneous and coarse flow simulation model. A new model was developed to include geological heterogeneities using a simple upscaling method. The Oseberg Fm. consists of an upper homogeneous unit (zone 2) and a lower unit containing thin barriers of shale and calcite cemented sandstone (zone 1). The barrier content varies laterally. When barriers are distributed in a complex 3D pattern, they reduce the upscaled horizontal transmissibility more than what is obtained by multiplying the sand permeability by the net-to-gross ratio (N/G). However, the transmissibility reduction strongly depends on the spatial distribution of barriers and their geometry. Therefore, a fine scale element model was used to derive the average transmissibility reduction as a function of N/G for alternative geological descriptions of the barriers. A geo-statistical method called General Marked Point Process was used to generate the fine scale descriptions. This work has resulted in a simple upscaling routine for horizontal transmissibility, which represents an effective bridge between geological evaluation of uncertainties and fluid flow simulation. The method combines geo-statistical and deterministic modelling in an elegant manner, recognising that most often these methods complement one another.

  1. Impact of vertical barriers on performance of pump-and-treat systems

    International Nuclear Information System (INIS)

    Although aquifer remediation by Pump-and-treat (PAT) is widely practiced, it is generally implemented as an effective means of plume containment, rather than as an efficient means of contaminant mass removal. The use of slurry cutoff walls has been recognized as a means of improving the performance of PAT with respect to hydraulic control. As part of a study on the use of decision analysis in the design of aquifer remediation systems, the economic tradeoffs between capital costs and risk reduction were compared for several alternative PAT strategies. This work included an evaluation of the use of vertical barriers as components of PAT systems, using numerical experiments to examine the impacts of vertical barriers on PAT reliability. The results indicated that the use of vertical barriers in conjunction with PAT can significantly improve the simulated system performance, but that the magnitude of the predicted enhancement and cost-effectiveness of the barrier system are dependent on site characteristics, barrier placement, and modeling assumptions

  2. Composite Pressure Vessel Including Crack Arresting Barrier

    Science.gov (United States)

    DeLay, Thomas K. (Inventor)

    2013-01-01

    A pressure vessel includes a ported fitting having an annular flange formed on an end thereof and a tank that envelopes the annular flange. A crack arresting barrier is bonded to and forming a lining of the tank within the outer surface thereof. The crack arresting barrier includes a cured resin having a post-curing ductility rating of at least approximately 60% through the cured resin, and further includes randomly-oriented fibers positioned in and throughout the cured resin.

  3. Frozen soil barriers for hazardous waste confinement

    Energy Technology Data Exchange (ETDEWEB)

    Dash, J.G.; Leger, R. [Univ. of Washington, Seattle, WA (United States); Fu, H.Y. [Univ. of California, Santa Barbara, CA (United States)

    1997-12-31

    Laboratory and full field measurements have demonstrated the effectiveness of artificial ground freezing for the containment of subsurface hazardous and radioactive wastes. Bench tests and a field demonstration have shown that cryogenic barriers are impenetrable to aqueous and non aqueous liquids. As a result of the successful tests the US Department of Energy has designated frozen ground barriers as one of its top ten remediation technologies.

  4. Fission Barriers of Compound Superheavy Nuclei

    OpenAIRE

    Pei, J C; Nazarewicz, W.; Sheikh, J. A.; Kerman, A. K.

    2009-01-01

    The dependence of fission barriers on the excitation energy of the compound nucleus impacts the survival probability of superheavy nuclei synthesized in heavy-ion fusion reactions. In this work, we investigate the isentropic fission barriers by means of the self-consistent nuclear density functional theory. The relationship between isothermal and isentropic descriptions is demonstrated. Calculations have been carried out for $^{264}$Fm, $^{272}$Ds, $^{278}$112, $^{292}$114, and $^{312}$124. F...

  5. Tantalum oxide coatings as candidate environmental barriers

    OpenAIRE

    Moldovan, Monica; Weyant, C. M.; Johnson, D. Lynn; Faber, K. T.

    2004-01-01

    Tantalum (Ta) oxide, due to its high-temperature capabilities and thermal expansion coefficient similar to silicon nitride, is a promising candidate for environmental barriers for silicon (Si) nitride-based ceramics. This paper focuses on the development of plasma-sprayed Ta oxide as an environmental barrier coating for silicon nitride. Using a D-optimal design of experiments, plasma-spray processing variables were optimized to maximize coating density. The effect of processing variables on c...

  6. Skin Barrier Dysfunction and the Atopic March

    DEFF Research Database (Denmark)

    Clausen, Maja-Lisa; Agner, Tove; Thomsen, Simon Francis

    The atopic diseases: atopic dermatitis, asthma and allergic rhinoconjunctivitis are frequent diseases in the population occurring sequentially in the young (the atopic march).The discovery of filaggrin gene (FLG) mutations and impairments in the skin barrier as predisposing factors for atopic......—with atopic dermatitis and FLG mutations being a prerequisite for the development of the other atopic diseases, particularly asthma. This review discusses the role of the skin barrier function, particularly the role of FLG mutations, in the atopic march....

  7. Breaching barriers to collaboration in public spaces

    DEFF Research Database (Denmark)

    Heinemann, Trine; Mitchell, Robb

    2014-01-01

    Technology provoking disparate individuals to collaborate or share experiences in the public space faces a difficult barrier, namely the ordinary social order of urban places. We employed the notion of the breaching experiment to explore how this barrier might be overcome. We analyse responses to a...... life in public spaces. Arising from this, we argue for the importance of qualities such as availability, facilitation, perspicuous settings, and perspicuous participants to encourage and support co-located strangers to collaborate and share experiences....

  8. Barriers To Communication In Distance Education

    OpenAIRE

    BERGE, Zane L.

    2013-01-01

    To a large extent education can be thought of as a communication process among the participants. This article focuses on distance education, which has both the general communication processes that in-person education venues possess, and also communication specific to the technologies that mediate the teaching and learning taking place at a distance. There are various opportunities and barriers to effective communication. An exhaustive review of literature regarding communication barriers to d...

  9. Drywall construction as a dental radiation barrier

    International Nuclear Information System (INIS)

    Six typical forms of drywall construction have been tested as barriers against primary and secondary dental x-radiation. It is concluded that this widely used type of wall construction is generally effective for this purpose, but with a heavy workload two thicknesses of wallboard on each side of the wall are required to provide a sufficient barrier. In general, no lead need be incorporated in the walls

  10. Drywall construction as a dental radiation barrier.

    Science.gov (United States)

    MacDonald, J C; Reid, J A; Berthoty, D

    1983-03-01

    Six typical forms of drywall construction have been tested as barriers against primary and secondary dental x-radiation. It is concluded that this widely used type of wall construction is generally effective for this purpose, but with a heavy workload two thicknesses of wallboard on each side of the wall are required to provide a sufficient barrier. In general, no lead need be incorporated in the walls. PMID:6572885

  11. Overcoming Affective Barriers in College English Learning

    Institute of Scientific and Technical Information of China (English)

    任永东

    2014-01-01

    Nowadays, the development of economy as well as the progress of society requires better English competence of col-lege students. As a result, a large number of college students are obsessedby affective barriers in their English learning, especially when they have to cope with CET 4 or CET 6, which is more and more difficult. This paper focuses on how to help college stu-dents overcome their affective barriers more effectively to improve their English learning.

  12. LANGUAGE BARRIERS: FEEDBACK FROM THE IT INDUSTRY

    OpenAIRE

    Sareen Kaur Bhar; Nor Azlah Abu Bakar

    2013-01-01

    Meaningful interaction process between human beings necessitates effective communication especially in organisations that have rapid information exchange demands. It is perceived that most IT organisations that face communication and language barriers have lost businesses due to higher product defect rates, lack of focus on business objectives, stifled innovation and dissatisfied customers and poor customer services. This study looks at the language barriers faced by employees working in var...

  13. A Semigroup Expansion for Pricing Barrier Options

    Directory of Open Access Journals (Sweden)

    Takashi Kato

    2014-01-01

    Full Text Available This paper presents a new asymptotic expansion method for pricing continuously monitoring barrier options. In particular, we develop a semigroup expansion scheme for the Cauchy-Dirichlet problem in the second-order parabolic partial differential equations (PDEs arising in barrier option pricing. As an application, we propose a concrete approximation formula under a stochastic volatility model and demonstrate its validity by some numerical experiments.

  14. Barriers and strategies in listening comprehension

    Institute of Scientific and Technical Information of China (English)

    张帆; 张金萍; 李爱娜

    2006-01-01

    A variety of barriers to listening comprehension are illustrated in this paper. They are analyzed respectively and several effective strategies are also presented afterward. The barriers to listening are those of psychological quality, language knowledge, cultural background, Chinese interference and so on. The strategies should be as follows: training students' psychological quality,strengthening the teaching and learning of language knowledge,comparing cultural differences, using student-centered teaching method and combining intensive listening and extensive listening.

  15. Phonic Attenuation due to Screen-Barriers

    OpenAIRE

    Vasile Bacria; Nicolae Herişanu

    2011-01-01

    The technique of noise decreasing admits two basic approaches: an active approach and a passive one. In the frame of passive method one can count the employment of screen-barriers. In this paper we present some considerations on sound attenuation due to screen-barriers emphasizing the elements which influence it. The elucidation of these elements is made by measurements. The obtained results can be applied in every other practical situation concerning the protection against ...

  16. The biological significance of brain barrier mechanisms

    DEFF Research Database (Denmark)

    Saunders, Norman R; Habgood, Mark D; Møllgård, Kjeld;

    2016-01-01

    Barrier mechanisms in the brain are important for its normal functioning and development. Stability of the brain's internal environment, particularly with respect to its ionic composition, is a prerequisite for the fundamental basis of its function, namely transmission of nerve impulses. In addit...... addition, such studies, if applied to brain pathologies such as stroke, trauma, or multiple sclerosis, will aid in defining the contribution of brain barrier pathology to these conditions, either causative or secondary....

  17. Addressing language barriers to healthcare in India.

    Science.gov (United States)

    Narayan, Lalit

    2013-01-01

    In spite of a growing recognition of the importance of doctor-patient communication, the issue of language barriers to healthcare has received very little attention in India. The Indian population speaks over 22 major languages with English used as the lingua franca for biomedicine. Large-scale internal migration has meant that health workers are encountering increasing instances of language discordance within clinical settings. Research done predominantly in the West has shown language discordance to significantly affect access to care, cause problems of comprehension and adherence, and decrease the satisfaction and quality of care. Addressing language barriers to healthcare in India requires a stronger political commitment to providing non-discriminatory health services, especially to vulnerable groups such as illiterate migrant workers. Research will have to address three broad areas: the ways in which language barriers affect health and healthcare, the efficacy of interventions to overcome language barriers, and the costs of language barriers and efforts to overcome them. There is a need to address such barriers in health worker education and clinical practice. Proven strategies such as hiring multilingual healthcare workers, providing language training to health providers, employing in situ translators or using telephone interpretation services will have to be evaluated for their appropriateness to the Indian context. Internet-based initiatives, the proliferation of mobile phones and recent advances in machine translation promise to contribute to the solution. PMID:24758452

  18. Stretchable graphene barriers for organic optoelectronic devices

    Science.gov (United States)

    Kong, Casey

    This thesis describes the use of a transparent, stretchable gas barrier film used to encapsulate organic devices in order to protect them from chemical degradation. One of the major issues with current organic semiconductor materials is that they are susceptible to degradation when exposed to oxygen and water vapor in the ambient atmosphere. In order to take advantage of these materials, stretchable barrier films must also be developed. Solar cell devices were fabricated using an organic bulk heterojunction blend of poly(3-heptylthiophene) and phenyl-C61-butyric acid methyl ester (P3HpT:PCBM). Stretchable barrier films were fabricated with graphene and polyurethane (PU) using a simple dip coating process. Devices encapsulated with an unstrained graphene/PU barrier film retained 60.6 +/- 3.7% efficiency after 10 days, exhibiting barrier properties similar to that of a control device encapsulated with glass (61.1 +/- 3.2%). Measurements over the course of 1 day showed that graphene/PU films strained up to 20% were still able to maintain 91.5 +/- 2.8% efficiency. Electrical resistance measurements showed that graphene cracks around 6% strain. This work highlights the potential impact graphene/PU barrier films may have on stretchable electronics.

  19. Model assessment of protective barriers: Part 3

    Energy Technology Data Exchange (ETDEWEB)

    Fayer, M.J.; Rockhold, M.L.; Holford, D.J.

    1992-02-01

    Radioactive waste exists at the US Department of Energy's (DOE's) Hanford Site in a variety of locations, including subsurface grout and tank farms, solid waste burial grounds, and contaminated soil sites. Some of these waste sites may need to be isolated from percolating water to minimize the potential for transport of the waste to the ground water, which eventually discharges to the Columbia River. Multilayer protective barriers have been proposed as a means of limiting the flow of water through the waste sites (DOE 1987). A multiyear research program (managed jointly by Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company for the DOE) is aimed at assessing the performance of these barriers. One aspect of this program involves the use of computer models to predict barrier performance. Three modeling studies have already been conducted and a test plan was produced. The simulation work reported here was conducted by PNL and extends the previous modeling work. The purpose of this report are to understand phenomena that have been observed in the field and to provide information that can be used to improve hydrologic modeling of the protective barrier. An improved modeling capability results in better estimates of barrier performance. Better estimates can be used to improve the design of barriers and the assessment of their long-term performance.

  20. The Infant Skin Barrier: Can We Preserve, Protect, and Enhance the Barrier?

    OpenAIRE

    Telofski, Lorena S.; A. Peter Morello; Catherine Mack Correa, M.; Stamatas, Georgios N.

    2012-01-01

    Infant skin is different from adult in structure, function, and composition. Despite these differences, the skin barrier is competent at birth in healthy, full-term neonates. The primary focus of this paper is on the developing skin barrier in healthy, full-term neonates and infants. Additionally, a brief discussion of the properties of the skin barrier in premature neonates and infants with abnormal skin conditions (i.e., atopic dermatitis and eczema) is included. As infant skin continues to...

  1. Determining collective barrier operation skew in a parallel computer

    Science.gov (United States)

    Faraj, Daniel A.

    2015-11-24

    Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by: identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.

  2. Determining collective barrier operation skew in a parallel computer

    Energy Technology Data Exchange (ETDEWEB)

    Faraj, Daniel A.

    2015-11-24

    Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by: identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.

  3. Determining collective barrier operation skew in a parallel computer

    Energy Technology Data Exchange (ETDEWEB)

    Faraj, Daniel A.

    2015-12-24

    Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by: identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.

  4. Alternative energy in Nepal

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, H.B.; Bhandari, K.P.

    2011-05-15

    Renewable energy Technology (RET) becomes the mainstream option for rural Nepal to access modern source of energy. It focuses on the trend of RET applications consisting of biogas technology, solar thermal, micro and Pico hydropower, biomass technology bio fuel technology, wind power technology etc. The RET's which provide both electricity based as well as non electricity based services, have been shown to most immediately meet the needs of a cleaner indoor environment, better quality lightning for education and income generating, activities, alternative cooking fuels and agro processing as well as rural industries. Improved cooking stoves and much more beneficial than other technologies. Wind energy utilization is still not popular. Solar thermal to generate thermal energy to cook, warm and dry, biogas for lighting and cooking services. Micro hydropower for electric as well as mechanical use and solar PV mainly for domestic lighting may become choice. The most important Renewable Energy Technology (RET's) in Nepal are related to Pico hydropower and micro-hydropower, biomass energy (biogas, briquettes, gasifies, improved cooking stoves, bio-fuels etc.) solar photovoltaic energy, solar PV water pumping, solar thermal energy (solar heater, solar dryers, solar cookers etc.) and wind energy (such as wind generators, wind mills etc.). One renowned Non-governmental organization has been established in the Jhapa and Mornag Bhutanese refugee camp. Two families from all the seven camps in Nepal received one solar cooker, one hay box and two cooking posts to each family. Under this programme, a total of 6,850 solar cookers, 12600 hay boxes and 25,200 cooking pots have been distributed 2009. The number of beneficiaries from this program has reached 85,000. Before the distribution of the cookers and the utensils, the instruction and orientation training for the maintenance and repair and operation method was improved. The refugees were divided in 315 groups of 40

  5. Normetex Pump Alternatives Study

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Elliot A.

    2013-04-25

    A mainstay pump for tritium systems, the Normetex scroll pump, is currently unavailable because the Normetex company went out of business. This pump was an all-metal scroll pump that served tritium processing facilities very well. Current tritium system operators are evaluating replacement pumps for the Normetex pump and for general used in tritium service. An all-metal equivalent alternative to the Normetex pump has not yet been identified. 1. The ideal replacement tritium pump would be hermetically sealed and contain no polymer components or oils. Polymers and oils degrade over time when they contact ionizing radiation. 2. Halogenated polymers (containing fluorine, chlorine, or both) and oils are commonly found in pumps. These materials have many properties that surpass those of hydrocarbon-based polymers and oils, including thermal stability (higher operating temperature) and better chemical resistance. Unfortunately, they are less resistant to degradation from ionizing radiation than hydrocarbon-based materials (in general). 3. Polymers and oils can form gaseous, condensable (HF, TF), liquid, and solid species when exposed to ionizing radiation. For example, halogenated polymers form HF and HCl, which are extremely corrosive upon reaction with water. If a pump containing polymers or oils must be used in a tritium system, the system must be designed to be able to process the unwanted by-products. Design features to mitigate degradation products include filters and chemical or physical traps (eg. cold traps, oil traps). 4. Polymer components can work in tritium systems, but must be replaced regularly. Polymer components performance should be monitored or be regularly tested, and regular replacement of components should be viewed as an expected normal event. A radioactive waste stream must be established to dispose of used polymer components and oil with an approved disposal plan developed based on the facility location and its regulators. Polymers have varying

  6. Influence of layer type and order on barrier properties of multilayer PECVD barrier coatings

    Science.gov (United States)

    Bahroun, K.; Behm, H.; Mitschker, F.; Awakowicz, P.; Dahlmann, R.; Hopmann, Ch

    2014-01-01

    Due to their macromolecular structure, plastics are limited in their scope of application whenever high barrier functionality against oxygen and water vapour permeation is required. One solution is the deposition of thin silicon oxide coatings in plasma-enhanced chemical vapour deposition (PECVD) processes. A way to improve performance of barrier coatings is the use of multilayer structures built from dyad layers, which combine an inorganic barrier layer and an organic intermediate layer. In order to investigate the influence of type and number of dyads on the barrier performance of coated 23 µm PET films, different dyad setups are chosen. The setups include SiOCH interlayers and SiOx-barrier layers deposited using the precursor hexamethyldisiloxane (HMDSO). A single reactor setup driven in pulsed microwave plasma (MW) mode as well as capacitively coupled plasma (CCP) mode is chosen. In this paper the effects of a variation in intermediate layer recipe and stacking order using dyad setups on the oxygen barrier properties of multilayer coatings are discussed with regard to the chemical structure, morphology and activation energy of the permeation process. Changes in surface nano-morphology of intermediate layers have a strong impact on the barrier properties of subsequent glass-like coatings. Even a complete failure of the barrier is observed. Therefore, when depositing multilayer barrier coatings, stacking order has to be considered.

  7. Influence of layer type and order on barrier properties of multilayer PECVD barrier coatings

    International Nuclear Information System (INIS)

    Due to their macromolecular structure, plastics are limited in their scope of application whenever high barrier functionality against oxygen and water vapour permeation is required. One solution is the deposition of thin silicon oxide coatings in plasma-enhanced chemical vapour deposition (PECVD) processes. A way to improve performance of barrier coatings is the use of multilayer structures built from dyad layers, which combine an inorganic barrier layer and an organic intermediate layer. In order to investigate the influence of type and number of dyads on the barrier performance of coated 23 µm PET films, different dyad setups are chosen. The setups include SiOCH interlayers and SiOx-barrier layers deposited using the precursor hexamethyldisiloxane (HMDSO). A single reactor setup driven in pulsed microwave plasma (MW) mode as well as capacitively coupled plasma (CCP) mode is chosen. In this paper the effects of a variation in intermediate layer recipe and stacking order using dyad setups on the oxygen barrier properties of multilayer coatings are discussed with regard to the chemical structure, morphology and activation energy of the permeation process. Changes in surface nano-morphology of intermediate layers have a strong impact on the barrier properties of subsequent glass-like coatings. Even a complete failure of the barrier is observed. Therefore, when depositing multilayer barrier coatings, stacking order has to be considered. (paper)

  8. Trade Barriers and Countermeasures for Export of China’s Agricultural Products

    OpenAIRE

    Wu, Lijing

    2013-01-01

    At present, export of China’s agricultural products is faced with many trade barriers, especially technological barriers. Trade barriers include (1) technological barriers (such as quarantine and inspection barrier, identity certification/authentication barrier and labeling rules barrier); (2) trade remedy barrier; (3) other non-tariff barriers (NTB). Through positioning and analysis of trade barriers of China’s agricultural products, it is known that technological barriers should not be ...

  9. Modeling and Simulation of Long-Term Performance of Near-Surface Barriers

    Energy Technology Data Exchange (ETDEWEB)

    Piet, Steven James; Jacobson, Jacob Jordan; Soto, Rafael; Martian, Pete; Martineau, Richard Charles

    2003-02-01

    Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surface water. The design lifespan for such barriers ranges from 30 to 1000 years, depending on hazard and regulations. In light of historical performance, society needs a better basis for predicting barrier performance over long time periods and tools for optimizing maintenance of barriers while in service. We believe that, as in other industries, better understanding of the dynamics of barrier system degradation will enable improved barriers (cheaper, longer-lived, simpler, easier to maintain) and improved maintenance. We are focusing our research on earthen caps, especially those with evapo-transpiration and capillary breaks. Typical cap assessments treat the barrier’s structure as static prior to some defined lifetime. Environmental boundary conditions such as precipitation and temperature are treated as time dependent. However, other key elements of the barrier system are regarded as constant, including engineered inputs (e.g., fire management strategy, irrigation, vegetation control), surface ecology (critical to assessment of plant transpiration), capillary break interface, material properties, surface erosion rate, etc. Further, to be conservative, only harmful processes are typically considered. A more holistic examination of both harmful and beneficial processes will provide more realistic pre-service prediction and in-service assessment of performance as well as provide designers a tool to encourage beneficial processes while discouraging harmful processes. Thus

  10. Preliminary evaluation of alternative forms for immobilization of Savannah River Plant high-level waste. [Eleven alternative solid forms

    Energy Technology Data Exchange (ETDEWEB)

    Stone, J.A.; Goforth, S.T. Jr.; Smith, P.K.

    1979-12-01

    An evaluation of available information on eleven alternative solid forms for immobilization of SRP high-level waste has been completed. Based on the assessment of both product and process characteristics, four forms were selected for more detailed evaluation: (1) borosilicate glass made in the reference process, (2) a high-silica glass made from a porous glass matrix, (3) crystalline ceramics such as supercalcine or SYNROC, and (4) ceramics coated with an impervious barrier. The assessment includes a discussion of product and process characteristics for each of the eleven forms, a cross comparison of these characteristics for the forms, and the bases for selecting the most promising forms for further study.

  11. Finding alternatives to swidden agriculture

    DEFF Research Database (Denmark)

    Rahman, Syed Ajijur; Jacobsen, Jette Bredahl; Healey, John Robert;

    2016-01-01

    Swidden cultivation can contribute to deforestation and land degradation, which can subsequently result in a number of serious environmental problems. This paper examines the economic and social potential of agroforestry systems and the barriers to their widespread adoption, as a land use...

  12. Alternatives of menopausal hormone therapy

    OpenAIRE

    Kutlešić Ranko M.; Popović Jasmina; Stefanović Milan; Vukomanović Predrag; Lukić Bojan; Lilić Goran

    2016-01-01

    Introduction. It has been generally accepted that the benefits of menopausal hormone therapy outweigh the risks, but there are still some concerns about the administration of menopausal hormone therapy, which has introduced alternative treatments. Pharmacological Alternatives. Central alpha-2 agonist clonidine is only marginally more effective than placebo, and significantly less effective than estrogen. Antiepileptic drug gabapentin reduces hot flashes; ho...

  13. Orion Project: Alternate Attitude Study

    Science.gov (United States)

    Alvarez-Hernandez, A.; Miller, Stephen W.

    2009-01-01

    This slide presentation reviews the study done on alternate attitudes for the Orion project's crew exploration vehicle. The analysis focused on the thermal performance of the vehicle with the alternate attitudes. The pressure vessel heater power, other vehicle heaters and radiator sink temperatures were included in the analysis.

  14. Alternative Fuels in Cement Production

    DEFF Research Database (Denmark)

    Larsen, Morten Boberg

    The substitution of alternative for fossil fuels in cement production has increased significantly in the last decade. Of these new alternative fuels, solid state fuels presently account for the largest part, and in particular, meat and bone meal, plastics and tyre derived fuels (TDF) accounted for...... the most significant alternative fuel energy contributors in the German cement industry. Solid alternative fuels are typically high in volatile content and they may differ significantly in physical and chemical properties compared to traditional solid fossil fuels. From the process point of view......, considering a modern kiln system for cement production, the use of alternative fuels mainly influences 1) kiln process stability (may accelerate build up of blockages preventing gas and/or solids flow), 2) cement clinker quality, 3) emissions, and 4) decreased production capacity. Kiln process stability in...

  15. Scale Modelling of Railway Noise Barriers

    Science.gov (United States)

    HOTHERSALL, D. C.; HOROSHENKOV, K. V.; MORGAN, P. A.; SWIFT, M. J.

    2000-07-01

    Experiments were carried out in an anechoic chamber using a 1:20 scale model of a high-speed train to determine the insertion loss of various forms of track-side noise barrier. All the barriers investigated had the upper edge level with the bottom of the train windows and were positioned as close as possible to the train, within the limitations of the structure gauge. They thus provided attenuation of noise from sources in the lower portion of the train, in the region of the rails and wheels. The measured performance of plane screens with rigid and sound-absorbing surfaces is compared with values predicted by standard prediction methods for railway noise and the results of a numerical model. The effect of barrier shape and absorptive surfaces upon screening performance is investigated. Results are presented in terms of the insertion loss of the peak SPL of the pass-by profile for a single bogie noise source and for the whole train, and also insertion loss based onLAeq,1 h . Results for these three measures show similar trends. For the conditions tested insertion loss values for all the screens were lower when the ground behind the barrier was absorbing than when the ground was rigid. The relative changes in insertion loss for the different forms of barrier were similar for the two ground types. Insertion loss values for rigid screens were between 6 and 10 dB lower than those for similar screens with complete sound absorbing surfaces. The application of absorbing areas on rigid screens significantly increases the insertion loss by between 3 and 6 dB. The least efficient screen was a corrugated barrier with a rigid surface. The most efficient screens tested were plane and curved barriers with absorbing surfaces and a multiple edge screen with a part-absorbing surface.

  16. Overcoming barriers to Clean Development Mechanism projects

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J. [OECD, Paris (France); Kamel, S. [UNEP Risoe Centre on Energy, Climate and Sustainable Development URC, Roskilde (Denmark)

    2007-05-15

    The market for Clean Development Mechanism (CDM) projects is continuing to grow rapidly, with the current portfolio expecting to deliver 2 billion tons of CO2-eq greenhouse gas (GHG) emission reductions by 2012, equivalent to 17% of Annex I Parties' base year GHG emissions. In total, governments and companies have earmarked over USD11 billion for CDM funding to 2012. This study analyses the various barriers to CDM market expansion in developing countries, and makes recommendations on how some of them can be removed or reduced. It also examines the distribution of CDM projects amongst regions and sectors. Different types of barriers can impede the development of CDM projects. These include: National-level barriers not related specifically to the CDM such as the policy or legislative framework within which a CDM project operates, e.g. electricity-related regulations that constrain generation by independent power producers; National-level CDM-related barriers such as institutional capability/effectiveness or lack of awareness about CDM potential. For example, delays in host country approval of CDM projects can dampen interest in CDM project development; Project-related issues including availability (or not) of underlying project finance, or other country or project-related risks that render the performance of the project uncertain; International-level barriers such as constraints on project eligibility (e.g. on land use and forestry projects), available guidance and decisions (e.g. with respect to the inclusion of carbon capture and storage projects), etc. Thus, barriers to CDM development can arise at different parts of the CDM project cycle. The relative importance of particular barriers varies between countries as well as over time. A combination of factors is needed to drive growth in a country's CDM activity. This includes the presence of attractive CDM opportunities, a positive investment climate, and an enabling policy and legislative framework (in

  17. Opportunities and barriers for international bioenergy trade

    International Nuclear Information System (INIS)

    Recently, the international trade of various bioenergy commodities has grown rapidly, yet this growth is also hampered by some barriers. The aim of this paper is to obtain an overview of what market actors currently perceive as major opportunities and barriers for the development of international bioenergy trade. The work focuses on three bioenergy commodities: bioethanol, biodiesel and wood pellets. Data were collected through an internet-based questionnaire. The majority of the 141 respondents had an industrial background. Geographically, two-thirds were from (mainly Western) Europe, with other minor contributions from all other continents. Results show that import tariffs and the implementation of sustainability certification systems are perceived as (potentially) major barriers for the trade of bioethanol and biodiesel, while logistics are seen mainly as an obstacle for wood pellets. Development of technical standards was deemed more as an opportunity than a barrier for all commodities. Most important drivers were high fossil fuel prices and climate change mitigation policies. Concluding, to overcome some of the barriers, specific actions will be required by market parties and policy makers. Import tariffs for biofuels could be reduced or abolished, linked to multinational trade agreements and harmonization (including provisions on technical standards and sustainability requirements). - Research highlights: → We analyze main barriers for global trade of wood pellets, ethanol and biodiesel. → Import tariffs can be a major barrier for liquid biofuels trade. → Implementation of sustainability certification systems may hamper biofuels trade. → Logistics are seen mainly as an obstacle for the trade of wood pellets. → Development of technical standards are deemed an opportunity for bioenergy trade.

  18. Fusion and peripheral reactions in the systems /sup 16/O+sup(148,152)Sm at sub-barrier energies

    Energy Technology Data Exchange (ETDEWEB)

    Kittl, J.A.; Testoni, J.E.

    1986-05-12

    Cross sections for fusion and peripheral reactions in the sub-barrier region obtained with the coupled-channel and equivalent-spheres methods are compared for the systems /sup 16/O+sup(148,152)Sm. A barrier-like real potential plus a residual surface-imaginary potential is introduced as an alternative approach which allows the simultaneous fit of elastic, inelastic, fusion and peripheral reaction cross sections.

  19. Circularly polarized antennas for active holographic imaging through barriers

    Science.gov (United States)

    McMakin, Douglas L [Richland, WA; Severtsen, Ronald H [Richland, WA; Lechelt, Wayne M [West Richland, WA; Prince, James M [Kennewick, WA

    2011-07-26

    Circularly-polarized antennas and their methods of use for active holographic imaging through barriers. The antennas are dielectrically loaded to optimally match the dielectric constant of the barrier through which images are to be produced. The dielectric loading helps to remove barrier-front surface reflections and to couple electromagnetic energy into the barrier.

  20. Model assessment of protective barrier designs: Part 2

    International Nuclear Information System (INIS)

    Protective barriers are being considered for use at the Hanford Site to enhance the isolation of radioactive wastes from water, plant, and animal intrusion. This study assesses the effectiveness of protective barriers for isolation of wastes from water. In this report, barrier designs are reviewed and several barrier modeling assumptions are tested. 20 refs., 16 figs., 6 tabs

  1. The long-term climate change assessmenet task of the protective barrier developoment program for low-level waste site remediation at the Hanford Site, Washington

    International Nuclear Information System (INIS)

    A study plan is being developed to guide a multiyear program to assess long-term climate change and optimize the design of protective barriers. A protective barrier alternative is being considered for the disposal of some low-level radioactive defense waste stored near the surface at the Hanford Site, Washington. These barriers are being designed to limit movement of radionuclides and other contaminants to the accessible environment for at least 1000 years and possibly as long as 10,000 years. A stepwise approach to climatic data acquisition will be relied on in obtaining needed information for concurrent barrier tasks, and in developing a local climate forecast model. This model will need to couple past climate patterns with models of regional and global climate drivers to provide bounding conditions for barrier performance assessment analyses. 9 refs., 3 figs

  2. Facilitating facial retinization through barrier improvement.

    Science.gov (United States)

    Draelos, Zoe Diana; Ertel, Keith D; Berge, Cynthia A

    2006-10-01

    The utility of topical tretinoin as a treatment for improving the appearance of photodamaged skin is limited by irritation that occurs during the early phases of facial retinization. The observed side effects are consistent with stratum corneum barrier compromise. This paired double-blinded study was conducted to determine if preconditioning the skin with a barrier-enhancing cosmetic facial moisturizer before beginning tretinoin therapy and continuing moisturizer application during therapy would mitigate these side effects. Women with facial photodamage were recruited and randomly assigned to apply one cosmetic moisturizer to one side of the face and the other cosmetic moisturizer to the other side of the face twice daily for 10 weeks. One moisturizer contained a mixture of vitamins (niacinamide, panthenol, and tocopheryl acetate) to enhance stratum corneum barrier function, and the other moisturizer contained similar moisturizing ingredients but no vitamins. Daily full-face treatment with tretinoin cream 0.025% commenced 2 weeks into the study. Subjects' facial skin condition was monitored via investigator assessments, instrumental measurements, and subject self-assessments. The results show that improving stratum corneum barrier function before beginning topical tretinoin therapy and continuing use of a barrier-enhancing cosmetic moisturizer during therapy facilitates the early phase of facial retinization and augments the treatment response. PMID:17121065

  3. Vertical barriers with increased sorption capacities

    Energy Technology Data Exchange (ETDEWEB)

    Bradl, H.B. [Bilfinger + Berger Bauaktiengesellschaft, Mannheim (Germany)

    1997-12-31

    Vertical barriers are commonly used for the containment of contaminated areas. Due to the very small permeability of the barrier material which is usually in the order of magnitude of 10-10 m/s or less the advective contaminant transport can be more or less neglected. Nevertheless, there will always be a diffusive contaminant transport through the barrier which is caused by the concentration gradient. Investigations have been made to increase the sorption capacity of the barrier material by adding substances such as organoclays, zeolites, inorganic oxides and fly ashes. The contaminants taken into account where heavy metals (Pb) and for organic contaminants Toluole and Phenantrene. The paper presents results of model calculations and experiments. As a result, barrier materials can be designed {open_quotes}tailor-made{close_quotes} depending on the individual contaminant range of each site (e.g. landfills, gasworks etc.). The parameters relevant for construction such as rheological properties, compressive strength and permeability are not affected by the addition of the sorbents.

  4. Field emission from finite barrier quantum structures

    International Nuclear Information System (INIS)

    We study field emission from various finite barrier quasi-low dimensional structures, taking image force into account. To proceed, we first formulate an expression for field emission current density from a quantum dot. Transverse dimensions of the dot are then increased in turn, to obtain current densities respectively from quantum wire and quantum well with infinite potential energy barriers. To find out field emission from finite barrier structures, the above analysis is followed with a correction in the energy eigen values. In course, variations of field emission current density with strength of the applied electric field and structure dimensions are computed considering n-GaAs and n-GaAs/AlxGa1−xAs as the semiconductor materials. In each case, the current density is found to increase exponentially with the applied field, while it oscillates with structure dimensions. The magnitude of the emission current is less when the image force is not considered, but retains the similar field dependence. In all cases, the field emission from infinite barrier structures exceeds those from respective finite barrier ones

  5. LANGUAGE BARRIERS: FEEDBACK FROM THE IT INDUSTRY

    Directory of Open Access Journals (Sweden)

    Sareen Kaur Bhar

    2013-02-01

    Full Text Available Meaningful interaction process between human beings necessitates effective communication especially in organisations that have rapid information exchange demands. It is perceived that most IT organisations that face communication and language barriers have lost businesses due to higher product defect rates, lack of focus on business objectives, stifled innovation and dissatisfied customers and poor customer services. This study looks at the language barriers faced by employees working in various fields related to Information Technology in Malaysia. A questionnaire was distributed to IT employees working in various international and national companies in Malaysia, and sixty two IT employees’ responses were accepted. The employees had to rate the effects of each language barrier on them in the context of the workplace. Based on these findings, barriers faced by IT employees in this field can now be better understood and steps can be taken by both the industry and education sectors to overcome these barriers. It will also aid these employees to be better communicators in facing the challenges in their industry and increase their competitiveness on a global scale. We conclude that future research should more explicitly consider the different configurations of language skills that are needed by IT staff.

  6. Vertical barriers with increased sorption capacities

    International Nuclear Information System (INIS)

    Vertical barriers are commonly used for the containment of contaminated areas. Due to the very small permeability of the barrier material which is usually in the order of magnitude of 10-10 m/s or less the advective contaminant transport can be more or less neglected. Nevertheless, there will always be a diffusive contaminant transport through the barrier which is caused by the concentration gradient. Investigations have been made to increase the sorption capacity of the barrier material by adding substances such as organoclays, zeolites, inorganic oxides and fly ashes. The contaminants taken into account where heavy metals (Pb) and for organic contaminants Toluole and Phenantrene. The paper presents results of model calculations and experiments. As a result, barrier materials can be designed 'tailor-made' depending on the individual contaminant range of each site (e.g. landfills, gasworks etc.). The parameters relevant for construction such as rheological properties, compressive strength and permeability are not affected by the addition of the sorbents

  7. Surface stability test plan for protective barriers

    International Nuclear Information System (INIS)

    Natural-material protective barriers for long-term isolation of buried waste have been identified as integral components of a plan to isolate a number of Hanford defense waste sites. Standards currently being developed for internal and external barrier performance will mandate a barrier surface layer that is resistant to the eolian erosion processes of wind erosion (deflation) and windborne particle deposition (formation of sand dunes). Thus, experiments are needed to measure rates of eolian erosion processes impacting those surfaces under different surface and climatological conditions. Data from these studies will provide information for use in the evaluation of selected surface layers as a means of providing stable cover over waste sites throughout the design life span of protective barriers. The multi-year test plan described in this plan is directed at understanding processes of wind erosion and windborne particle deposition, providing measurements of erosion rates for models, and suggesting construction materials and methods for reducing the effect of long-term eolian erosion on the barrier. Specifically, this plan describes possible methods to measure rates of eolian erosion, including field and laboratory procedure. Advantages and disadvantages of laboratory (wind tunnel) tests are discussed, and continued wind tunnel tests are recommended for wind erosion studies. A comparison between field and wind tunnel erosive forces is discussed. Plans for testing surfaces are described. Guidance is also presented for studying the processes controlling sand dune and blowout formation. 24 refs., 7 figs., 3 tabs

  8. Enhanced Densification of SDC Barrier Layers

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, John S.; Templeton, Jared W.; Lu, Zigui; Stevenson, Jeffry W.

    2011-09-12

    This technical report explores the Enhanced Densification of SCD Barrier Layers A samaria-doped ceria (SDC) barrier layer separates the lanthanum strontium cobalt ferrite (LSCF) cathode from the yttria-stabilized zirconia (YSZ) electrolyte in a solid oxide fuel cell (SOFC) to prevent the formation of electrically resistive interfacial SrZrO{sub 3} layers that arise from the reaction of Sr from the LSCF with Zr from the YSZ. However, the sintering temperature of this SDC layer must be limited to {approx}1200 C to avoid extensive interdiffusion between SDC and YSZ to form a resistive CeO{sub 2}-ZrO{sub 2} solid solution. Therefore, the conventional SDC layer is often porous and therefore not as impervious to Sr-diffusion as would be desired. In the pursuit of improved SOFC performance, efforts have been directed toward increasing the density of the SDC barrier layer without increasing the sintering temperature. The density of the SDC barrier layer can be greatly increased through small amounts of Cu-doping of the SDC powder together with increased solids loading and use of an appropriate binder system in the screen print ink. However, the resulting performance of cells with these barrier layers did not exhibit the expected increase in accordance with that achieved with the prototypical PLD SDC layer. It was determined by XRD that increased sinterability of the SDC also results in increased interdiffusivity between the SDC and YSZ, resulting in formation of a highly resistive solid solution.

  9. Reduced barrier efficiency in axillary stratum corneum.

    Science.gov (United States)

    Watkinson, A; Lee, R S; Moore, A E; Pudney, P D A; Paterson, S E; Rawlings, A V

    2002-06-01

    The skin of the axilla is cosmetically important with millions of consumers daily applying antiperspirant/deodorant products. Despite this, we know virtually nothing about axillary skin or how antiperspirant (AP) use impacts upon it. To characterize the axillary stratum corneum and determine whether this is a unique skin type, we have looked at stratum corneum composition and function, particularly its barrier properties, and compared it with other body sites. Transepidermal water loss (TEWL) and corneosurfametry (CSM) revealed a reduced barrier function in the axilla. HPTLC analysis of the stratum corneum lipids demonstrated statistically elevated levels of fatty acids, ceramides, and particularly cholesterol in the axilla. Both ceramide and cholesterol did not appear to change with depth, indicating that they were predominantly of stratum corneum origin. On the other hand, at least some of the fatty acid had a sebaceous origin. We hypothesized that the reduced barrier function might be owing to the changes in the crucial ceramide : cholesterol ratio. To address this, we used a combination of attenuated total reflectance-Fourier-transformed infrared spectroscopy (ATR-FTIR) with cyanoacrylate sampling. These results demonstrated more ordered lipid-lamellae phase behaviour in the axilla, suggesting that the elevated cholesterol might form crystal microdomains within the lipid lamellae, allowing an increase in water flux. Since an exaggerated application of antiperspirant had no effect upon the axilla barrier properties, it is concluded that this region of skin physiologically has a reduced barrier function. PMID:18498507

  10. NASA Alternative Aviation Fuel Research

    Science.gov (United States)

    Anderson, B. E.; Beyersdorf, A. J.; Thornhill, K. L., II; Moore, R.; Shook, M.; Winstead, E.; Ziemba, L. D.; Crumeyrolle, S.

    2015-12-01

    We present an overview of research conducted by NASA Aeronautics Research Mission Directorate to evaluate the performance and emissions of "drop-in" alternative jet fuels, highlighting experiment design and results from the Alternative Aviation Fuel Experiments (AAFEX-I & -II) and Alternative Fuel-Effects on Contrails and Cruise Emissions flight series (ACCESS-I & II). These projects included almost 100 hours of sampling exhaust emissions from the NASA DC-8 aircraft in both ground and airborne operation and at idle to takeoff thrust settings. Tested fuels included Fischer-Tropsch (FT) synthetic kerosenes manufactured from coal and natural-gas feedstocks; Hydro-treated Esters and Fatty-Acids (HEFA) fuels made from beef-tallow and camelina-plant oil; and 50:50 blends of these alternative fuels with Jet A. Experiments were also conducted with FT and Jet A fuels doped with tetrahydrothiophene to examine the effects of fuel sulfur on volatile aerosol and contrail formation and microphysical properties. Results indicate that although the absence of aromatic compounds in the alternative fuels caused DC-8 fuel-system leaks, the fuels did not compromise engine performance or combustion efficiency. And whereas the alternative fuels produced only slightly different gas-phase emissions, dramatic reductions in non-volatile particulate matter (nvPM) emissions were observed when burning the pure alternative fuels, particularly at low thrust settings where particle number and mass emissions were an order of magnitude lower than measured from standard jet fuel combustion; 50:50 blends of Jet A and alternative fuels typically reduced nvPM emissions by ~50% across all thrust settings. Alternative fuels with the highest hydrogen content produced the greatest nvPM reductions. For Jet A and fuel blends, nvPM emissions were positively correlated with fuel aromatic and naphthalene content. Fuel sulfur content regulated nucleation mode aerosol number and mass concentrations within aging

  11. Numerical Analysis of the Efficiency of Different Median Barrier Models in the Presence of a Plain Roadside Noise Barrier

    Directory of Open Access Journals (Sweden)

    Samaneh Momen Bellah Fard

    2011-06-01

    Full Text Available Roadside noise barrier as the noise control solution is extensively applied to reduce noise pollution. Median barrier like roadside barriers can make insertion loss at the receiver's area making a shadow zone behind the screen. However, the performance of roadside barrier can be affected by erecting a median barrier. Mainly a median barrier is considered as an extra structure to decrease the cross median crashes at highways. The aim of this study was to investigate the effectiveness of some treatments such as absorbent material and diffusers on various median barriers shapes. A 2D boundary element method was used to analyze the designed median barrier effects. Application of grass on the top surface of median barriers with even cap was more effective than those median barriers that had uneven cap. Utilizing Primitive Root Diffuser (PRD and Quadratic Residue Diffuser (QRD on the stem surface of median barrier has high efficiency due to cancel outing multiple reflection effects between roadside barrier and median barrier by 2.2 to 2.7 dB (A, while no improvement could be seen at median barriers with QRD and PRD tops. Finally, it can be stated that the performance of most median barriers were increased using the reactive surfaces on the stem sides of the barrier, while the top surface treatment was not very effective in this kind of screens.

  12. Traveling Towards Disease: Transportation Barriers to Health Care Access

    OpenAIRE

    Syed, Samina T.; Gerber, Ben S.; Sharp, Lisa K.

    2013-01-01

    Transportation barriers are often cited as barriers to healthcare access. Transportation barriers lead to rescheduled or missed appointments, delayed care, and missed or delayed medication use. These consequences may lead to poorer management of chronic illness and thus poorer health outcomes. However, the significance of these barriers is uncertain based on existing literature due to wide variability in both study populations and transportation barrier measures. The authors sought to synthes...

  13. Barriers to Physical Activity Among Patients With Type 1 Diabetes

    OpenAIRE

    Brazeau, Anne-Sophie; Rabasa-Lhoret, Rémi; Strychar, Irene; Mircescu, Hortensia

    2008-01-01

    OBJECTIVE—To determine, in an adult population with type 1 diabetes, barriers to regular physical activity using a diabetes-specific barriers measure (the Barriers to Physical Activity in Diabetes [type 1] [BAPAD1] scale) and factors associated with these barriers. RESEARCH DESIGN AND METHODS—One hundred adults with type 1 diabetes answered a questionnaire assessing perceived barriers to physical activity and related factors. A1C was obtained from the medical chart of each individual. RESULTS...

  14. Comparison of the Ac barrier corona with DC positive and negative coronas and barrier discharge

    International Nuclear Information System (INIS)

    Results are presented from experimental studies of ac corona discharges between a point electrode and a dielectric-coated plate in nitrogen, argon, helium, and air in the voltage frequency range f = 50 Hz-50 kHz. The characteristic features of this type of discharge are compared with the well-known features of dc positive and negative coronas and a barrier discharge between plane electrodes. It is shown that the presence of a dielectric barrier on the plane electrode significantly changes the electric characteristics and spatial structure of the corona, whereas the main phases of the discharge evolution remain unchanged as the voltage increases. With a point electrode, the breakdown voltage of the barrier corona decreases substantially as compared to the breakdown voltage of a barrier discharge with plane electrodes. This leads to softer conditions for the streamer formation in a barrier corona, which becomes more stable against spark generation

  15. Energy barriers, entropy barriers, and non-Arrhenius behavior in a minimal glassy model

    Science.gov (United States)

    Du, Xin; Weeks, Eric R.

    2016-06-01

    We study glassy dynamics using a simulation of three soft Brownian particles confined to a two-dimensional circular region. If the circular region is large, the disks freely rearrange, but rearrangements are rarer for smaller system sizes. We directly measure a one-dimensional free-energy landscape characterizing the dynamics. This landscape has two local minima corresponding to the two distinct disk configurations, separated by a free-energy barrier that governs the rearrangement rate. We study several different interaction potentials and demonstrate that the free-energy barrier is composed of a potential-energy barrier and an entropic barrier. The heights of both of these barriers depend on temperature and system size, demonstrating how non-Arrhenius behavior can arise close to the glass transition.

  16. Numerical valuation of discrete double barrier options

    Science.gov (United States)

    Milev, Mariyan; Tagliani, Aldo

    2010-03-01

    In the present paper we explore the problem for pricing discrete barrier options utilizing the Black-Scholes model for the random movement of the asset price. We postulate the problem as a path integral calculation by choosing approach that is similar to the quadrature method. Thus, the problem is reduced to the estimation of a multi-dimensional integral whose dimension corresponds to the number of the monitoring dates. We propose a fast and accurate numerical algorithm for its valuation. Our results for pricing discretely monitored one and double barrier options are in agreement with those obtained by other numerical and analytical methods in Finance and literature. A desired level of accuracy is very fast achieved for values of the underlying asset close to the strike price or the barriers. The method has a simple computer implementation and it permits observing the entire life of the option.

  17. Barriers To Successful Implementation of STEM Education

    Directory of Open Access Journals (Sweden)

    James A. Ejiwale

    2013-05-01

    Full Text Available The implementation of STEM education in schools across the globe is to prepare the future workforce with strong scientific and mathematical backgrounds to enhance skills development across STEM disciplines. However, for STEM education to achieve its goals and objectives, addressing the barriers to STEM education should start by fixing the problems at the elementary, junior and senior high school levels; the grassroots and potential feeders to colleges and universities. Since many nations including the United States of America is in dire need of the workforce with adequate preparation in science and mathematics to help address the nation’s economy that is in shambles, the barriers to its successful implementation should be identified and addressed. In this paper, (a the definition of STEM education and (b some barriers to successful implementation of STEM education are discussed and elaborated.

  18. Constructing bottom barriers with met grouting

    Energy Technology Data Exchange (ETDEWEB)

    Shibazaki, M.; Yoshida, H. [Chemical Grouting Company, Tokyo (Japan)

    1997-12-31

    Installing a bottom barrier using conventional high pressure jetting technology and ensuring barrier continuity is challenging. This paper describes technology that has been developed and demonstrated for the emplacement of bottom barriers using pressures and flow rates above the conventional high pressure jetting parameters. The innovation capable of creating an improved body exceeding 5 meters in diameter has resulted in the satisfying connection and adherence between the treated columns. Besides, the interfaces among the improved bodies obtain the same strength and permeability lower than 1 x 10{sup -7} cm/sec as body itself. A wide variety of the thickness and the diameter of the improved mass optimizes the application, and the method is nearing completion. The paper explains an aspect and briefs case histories.

  19. Barrier bucket method in cyclic accelerators

    International Nuclear Information System (INIS)

    The paper describes the main principles of the Barrier Bucket Method of charge particles stacking and acceleration in proton synchrotrons. The consideration is done with two models of 'rectangular barriers' and 'quasi-sinusoidal' ones using different approaches to analysis of particle motion. The first of them - so-called 'step by step approach', allows us to give a very clear physical explanation of the method and obtain easily the main characteristics of the method in analytical form. However, that is not always an efficient way. Therefore, the general case of the 'barriers' of an arbitrary form is considered as well and differential equations of particle phase motion are derived. This approach gives ample opportunities for analysis and numerical simulations of different phase dynamics regimes of particles in cyclic accelerators. Numerical examples for the method illustration are presented

  20. Membrane barriers for radon gas flow restrictions

    International Nuclear Information System (INIS)

    Research was performed to assess the feasibility of barrier membrane substances, for use within mining or associated high risk environments, in restricting the diffusion transport of radon gas quantities. Specific tests were conducted to determine permeability parameters of a variety of membrane materials with reference to radon flow capabilities. Tests were conducted both within laboratory and in-situ emanation environments where concentrations and diffusion flows of radon gas were known to exist. Equilibrium radon gas concentrations were monitored in initially radon-free chambers adjacent to gas sources, but separated by specified membrane substances. Membrane barrier effectiveness was demonstrated to result in reduced emanation concentrations of radon gas within the sampling chamber atmosphere. Minimum gas concentrations were evidenced where the barrier membrane material was shown to exhibit lowest radon permeability characteristics

  1. Phonon tunneling through a double barrier system

    Energy Technology Data Exchange (ETDEWEB)

    Villegas, Diosdado [Departamento de Física, Universidad Central “Marta Abreu” de Las Villas, CP 54830, Santa Clara, Villa Clara (Cuba); Instituto de Física, Universidad Autónoma de Puebla, 18 Sur y San Claudio, Edif. 110A, Ciudad Universitaria, 72570 Puebla (Mexico); León-Pérez, Fernando de [Centro Universitario de la Defensa de Zaragoza, Ctra. de Huesca s/n, E-50090 Zaragoza (Spain); Pérez-Álvarez, R. [Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209 Cuernavaca (Mexico); Arriaga, J., E-mail: arriaga@ifuap.buap.mx [Instituto de Física, Universidad Autónoma de Puebla, 18 Sur y San Claudio, Edif. 110A, Ciudad Universitaria, 72570 Puebla (Mexico)

    2015-04-15

    The tunneling of optical and acoustic phonons at normal incidence on a double-barrier is studied in this paper. Transmission coefficients and resonance conditions are derived theoretically under the assumption that the long-wavelength approximation is valid. It is shown that the behavior of the transmission coefficients for the symmetric double barrier has a Lorentzian form close to resonant frequencies and that Breit–Wigner's formula have a general validity in one-dimensional phonon tunneling. Authors also study the so-called generalized Hartman effect in the tunneling of long-wavelength phonons and show that this effect is a numerical artifact resulting from taking the opaque limit before exploring the variation with a finite barrier width. This study could be useful for the design of acoustic devices.

  2. Identify and Rank Barriers to Tourism Development

    Directory of Open Access Journals (Sweden)

    Parchekani Choozaki Parvaneh

    2013-07-01

    Full Text Available This is a survey study and is practical and in nature is analytical descriptive. This is an analytical study because samples were used to collect data and it is descriptive because its variables are studied and reported as there are in the real world. In this study we study the barriers to tourism development and will rank the barriers for the use planners. In this study, to determine the validity the content validity was determined and to determine reliability the Cronbach's alpha method has been used. Also to check the normality of questions’ answers the Kolmogorov - Smirnov test is used. The sample population has also been determined by computational methods. In conclusion, according to the results of questionnaires and fuzzy Analytical Hierarchy process method, results were presented in two parts: result analysis for ranking the barriers to the development of tourism and suggestions.

  3. K-Basins isolation barriers summary report

    International Nuclear Information System (INIS)

    The purpose of this report is to provide an information summary for the 100-K Area fuel storage basins design change. The design change was made to resolve an unreviewed safety question related to potential water leakage from the basin following a design basis earthquake. The design change consists of installing isolation barriers in the K-East and K-West Basins. The barriers are installed in each basin to isolate the fuel storage portion of the basin from the location of the potential seismic induced leak. The summary represented by this report provides information on the issue, the courses of corrective action, the technical work to support the corrective action, and the fabrication, installation, testing of the isolation barriers

  4. Storm impacts on small barrier islands

    DEFF Research Database (Denmark)

    Kroon, Aart; Fruergaard, Mikkel

    changes in this evolution due to changes in the climate and associated sea levels. We analyzed the morphologic evolution of a series of barrier islands over the last decades using maps, aerial photographs and satellite images. This decadal morphologic evolution was coupled to the frequency and intensity...... of the local extreme events. The characterization of the extreme events was based on the joint probability of the extreme water levels and storm waves for the specific sites. The predicted climate change for the Danish waters will lead to higher water levels and an increase of the overwashes on the......The shorelines of the Baltic Sea and the inner coastal waters in Denmark consist of many barrier islands. These sandy barrier islands were mainly formed in the Holocene and are still very dynamic. The present day changes in the morphology are dominantly governed by storm waves and associated high...

  5. Epidermal Growth Factor and Intestinal Barrier Function

    Science.gov (United States)

    Liu, Hu; Yang, Shufen; Li, Zuohua; Zhong, Jinfeng

    2016-01-01

    Epidermal growth factor (EGF) is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health. PMID:27524860

  6. Surface barrier research at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Gee, G.W.; Ward, A.L.; Fayer, M.J. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-12-31

    At the DOE Hanford Site, a field-scale prototype surface barrier was constructed in 1994 over an existing waste site as a part of a CERCLA treatability test. The above-grade barrier consists of a fine-soil layer overlying coarse layers of sands, gravels, basalt rock (riprap), and a low permeability asphalt layer. Two sideslope configurations, clean-fill gravel on a 10:1 slope and basalt riprap on a 2:1 slope, were built and are being tested. Design considerations included: constructability; drainage and water balance monitoring, wind and water erosion control and monitoring; surface revegetation and biotic intrusion; subsidence and sideslope stability, and durability of the asphalt layer. The barrier is currently in the final year of a three-year test designed to answer specific questions related to stability and long-term performance. One half of the barrier is irrigated such that the total water applied, including precipitation, is 480 mm/yr (three times the long-term annual average). Each year for the past two years, an extreme precipitation event (71 mm in 8 hr) representing a 1,000-yr return storm was applied in late March, when soil water storage was at a maximum. While the protective sideslopes have drained significant amounts of water, the soil cover (2-m of silt-loam soil overlying coarse sand and rock) has never drained. During the past year there was no measurable surface runoff or wind erosion. This is attributed to extensive revegetation of the surface. In addition, the barrier elevation has shown a small increase of 2 to 3 cm that is attributed to a combination of root proliferation and freeze/thaw activity. Testing will continue through September 1997. Performance data from the prototype barrier will be used by DOE in site-closure decisions at Hanford.

  7. Skin barrier modification with organic solvents.

    Science.gov (United States)

    Barba, Clara; Alonso, Cristina; Martí, Meritxell; Manich, Albert; Coderch, Luisa

    2016-08-01

    The primary barrier to body water loss and influx of exogenous substances resides in the stratum corneum (SC). The barrier function of the SC is provided by patterned lipid lamellae localized to the extracellular spaces between corneocytes. SC lipids are intimately involved in maintaining the barrier function. It is generally accepted that solvents induce cutaneous barrier disruption. The main aim of this work is the evaluation of the different capability of two solvent systems on inducing changes in the SC barrier function. SC lipid modifications will be evaluated by lipid analysis, water sorption/desorption experiments, confocal-Raman visualization and FSTEM images. The amount of SC lipids extracted by chloroform/methanol was significantly higher than those extracted by acetone. DSC results indicate that acetone extract has lower temperature phase transitions than chloroform/methanol extract. The evaluation of the kinetics of the moisture uptake and loss demonstrated that when SC is treated with chloroform/methanol the resultant sample reach equilibrium in shorter times indicating a deterioration of the SC tissue with higher permeability. Instead, acetone treatment led to a SC sample with a decreased permeability thus with an improved SC barrier function. Confocal-Raman and FSTEM images demonstrated the absence of the lipids on SC previously treated with chloroform/methanol. However, they were still present when the SC was treated with acetone. Results obtained with all the different techniques used were consistent. The results obtained increases the knowledge of the interaction lipid-solvent, being this useful for understanding the mechanism of reparation of damaged skin. PMID:27184268

  8. Surface barrier research at the Hanford Site

    International Nuclear Information System (INIS)

    At the DOE Hanford Site, a field-scale prototype surface barrier was constructed in 1994 over an existing waste site as a part of a CERCLA treatability test. The above-grade barrier consists of a fine-soil layer overlying coarse layers of sands, gravels, basalt rock (riprap), and a low permeability asphalt layer. Two sideslope configurations, clean-fill gravel on a 10:1 slope and basalt riprap on a 2:1 slope, were built and are being tested. Design considerations included: constructability; drainage and water balance monitoring, wind and water erosion control and monitoring; surface revegetation and biotic intrusion; subsidence and sideslope stability, and durability of the asphalt layer. The barrier is currently in the final year of a three-year test designed to answer specific questions related to stability and long-term performance. One half of the barrier is irrigated such that the total water applied, including precipitation, is 480 mm/yr (three times the long-term annual average). Each year for the past two years, an extreme precipitation event (71 mm in 8 hr) representing a 1,000-yr return storm was applied in late March, when soil water storage was at a maximum. While the protective sideslopes have drained significant amounts of water, the soil cover (2-m of silt-loam soil overlying coarse sand and rock) has never drained. During the past year there was no measurable surface runoff or wind erosion. This is attributed to extensive revegetation of the surface. In addition, the barrier elevation has shown a small increase of 2 to 3 cm that is attributed to a combination of root proliferation and freeze/thaw activity. Testing will continue through September 1997. Performance data from the prototype barrier will be used by DOE in site-closure decisions at Hanford

  9. SAGE--SOLVENT ALTERNATIVES GUIDE

    Science.gov (United States)

    SAGE is a comprehensive guide designed to provide pollution prevention information on solvent and process alternatives for parts cleaning and degreasing. SAGE does not recommend any ozone depleting chemicals. SAGE was developed by the Surface Cleaning Program at Research Triang...

  10. Alternate Propellant Thermal Rocket Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Alternate Propellant Thermal Rocket (APTR) is a novel concept for propulsion of space exploration or orbit transfer vehicles. APTR propulsion is provided by...

  11. Herbs, Supplements and Alternative Medicines

    Science.gov (United States)

    ... Size: A A A Listen En Español Herbs, Supplements and Alternative Medicines It is best to get ... also more likely to use dietary supplements. Using Supplements Safely If you’re one of the many ...

  12. Alternative food safety intervention technologies

    Science.gov (United States)

    Alternative nonthermal and thermal food safety interventions are gaining acceptance by the food processing industry and consumers. These technologies include high pressure processing, ultraviolet and pulsed light, ionizing radiation, pulsed and radiofrequency electric fields, cold atmospheric plasm...

  13. Alternating Quotients of Fuchsian Groups

    OpenAIRE

    Everitt, Brent

    1999-01-01

    It is shown that any finitely generated non-elementary Fuchsian group has among its homomorphic images all but finitely many of the alternating groups. This settles in the affirmative a conjecture of Graham Higman.

  14. Resilience of alternative states in spatially extended ecosystems.

    Directory of Open Access Journals (Sweden)

    Ingrid A van de Leemput

    Full Text Available Alternative stable states in ecology have been well studied in isolated, well-mixed systems. However, in reality, most ecosystems exist on spatially extended landscapes. Applying existing theory from dynamic systems, we explore how such a spatial setting should be expected to affect ecological resilience. We focus on the effect of local disturbances, defining resilience as the size of the area of a strong local disturbance needed to trigger a shift. We show that in contrast to well-mixed systems, resilience in a homogeneous spatial setting does not decrease gradually as a bifurcation point is approached. Instead, as an environmental driver changes, the present dominant state remains virtually 'indestructible', until at a critical point (the Maxwell point its resilience drops sharply in the sense that even a very local disturbance can cause a domino effect leading eventually to a landscape-wide shift to the alternative state. Close to this Maxwell point the travelling wave moves very slow. Under these conditions both states have a comparable resilience, allowing long transient co-occurrence of alternative states side-by-side, and also permanent co-existence if there are mild spatial barriers. Overall however, hysteresis may mostly disappear in a spatial context as one of both alternative states will always tend to be dominant. Our results imply that local restoration efforts on a homogeneous landscape will typically either fail or trigger a landscape-wide transition. For extensive biomes with alternative stable states, such as tundra, steppe and forest, our results imply that, as climatic change reduces the stability, the effect might be difficult to detect until a point where local disturbances inevitably induce a spatial cascade to the alternative state.

  15. Alternative theories of the firm

    OpenAIRE

    Staněk, Jan

    2014-01-01

    This thesis is focusing on alternative theories of the firm and their distinctions to the traditional neoclassical theory of profit maximization. It goes back to perception of the firm in the society and to development of theoretical concepts of the firm, as well as to different points of view of profit or satisfaction principle. You will learn more about the reason which triggered the beginnings of alternative theories of the firm like separation of ownership and control, which was one of th...

  16. Alternative investments: return driving actors

    OpenAIRE

    Elliott, K; G. Marcato

    2011-01-01

    In an asset allocation process, correlations are particularly important if one includes 'alternative investments' such as real estate, commodities and hedge funds, which have been proclaimed to provide diversifying benefits within the overall portfolio context. However, by looking at correlations between asset classes alone some diversification benefits may be over or under-stated. More recently, finance literature has focused on alternative asset classes to study their behaviour and to ident...

  17. Spent-fuel-storage alternatives

    International Nuclear Information System (INIS)

    The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed

  18. Autocratic strategies for alternating games

    OpenAIRE

    McAvoy, Alex; Hauert, Christoph

    2016-01-01

    Repeated games have a long tradition in behavioral sciences and evolutionary biology. Recently, strategies were discovered that permit an unprecedented level of control over repeated interactions by enabling a player to unilaterally enforce constraints on the payoffs. Here, we extend this theory of autocratic (or zero-determinant) strategies to alternating games, which are often more biologically relevant than synchronous games. More specifically, in a strictly-alternating game with two playe...

  19. The neurogenetics of alternative splicing

    OpenAIRE

    Vuong, CK; Black, DL; S. Zheng

    2016-01-01

    Alternative precursor-mRNA splicing is a key mechanism for regulating gene expression in mammals and is controlled by specialized RNA-binding proteins. The misregulation of splicing is implicated in multiple neurological disorders. We describe recent mouse genetic studies of alternative splicing that reveal its critical role in both neuronal development and the function of mature neurons. We discuss the challenges in understanding the extensive genetic programmes controlled by proteins that r...

  20. Valuation of Discrete Barrier American Options

    Directory of Open Access Journals (Sweden)

    Carlos Patrício Samanez

    2009-09-01

    Full Text Available This article presents an approach and a model to valuing discrete barrier American options. The developed model consists of an adaptation of the method of Grant, Vora and Weeks (1997, in order to allow to incorporate the barriers. The Hybrid Quasi-Monte Carlo method was used in the simulations and the Bisection method in the definition of the options trigger curves. The results found in the application of the developed model were compared with the estimated by the Adaptive Mesh Model, developed by Ahn et al (1999. In addition, the sensitivity of the options price relative to changes in inputs parameters was analyzed, confirming the consistence of the model.

  1. ON AFFECTIVE BARRIERS TO LANGUAGE LEARNING

    Institute of Scientific and Technical Information of China (English)

    XiangMaoying

    2004-01-01

    Affective factors play a significant role in languagelearning. This paper argues that positive emotions can facilitatethe language learning process and improve learners' languageperformance, while negative emotions will bring barriers tolanguage learning and reduce learners learning capacity. Withtwo true stories as an introduction and some relevant answersobtained from my questionnaire, this paper mainly discusses theinfluences of negative emotional factors on language learning.such as anxiety, low self-esteem, insecure classroomatmosphere, lack of rapport between teachers and students, etc.Some suggestions about how to overcome affective barriers areput forward.

  2. Transmission line including support means with barriers

    Science.gov (United States)

    Cookson, Alan H.

    1982-01-01

    A gas insulated transmission line includes an elongated outer sheath, a plurality of inner conductors disposed within and extending along the outer sheath, and an insulating gas which electrically insulates the inner conductors from the outer sheath. A support insulator insulatably supports the inner conductors within the outer sheath, with the support insulator comprising a main body portion including a plurality of legs extending to the outer sheath, and barrier portions which extend between the legs. The barrier portions have openings therein adjacent the main body portion through which the inner conductors extend.

  3. Compositional Safety Analysis using Barrier Certificates

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Pappas, George J.; Wisniewski, Rafael

    2012-01-01

    This paper proposes a compositional method for verifying the safety of a dynamical system, given as an interconnection of subsystems. The safety verification is conducted by the use of the barrier certificate method; hence, the contribution of this paper is to show how to obtain compositional...... conditions for safety verification. We show how to formulate the verification problem, as a composition of coupled subproblems, each given for one subsystem. Furthermore, we show how to find the compositional barrier certificates via linear and sum of squares programming problems. The proposed method makes...

  4. Development of dielectric barrier discharging power supply

    Science.gov (United States)

    Gao, Yinghui; Liu, Kun; Fu, Rongyao; Sun, Yaohong; Yan, Ping

    2015-11-01

    Due to the demand of a dielectric barrier discharge power supply, a high voltage and high frequency AC power supply was designed and implemented. Its output voltage is standard or approximate standard sine waveform with the frequency range of 1 kHz to 50 kHz. The output voltage and output frequency can be adjusted individually. The maximum output power of the power supply is 2 kW. It can be operated through local or remote control. The power supply has been used in the dielectric barrier discharging research under different conditions.

  5. Message maps for safety barrier awareness

    DEFF Research Database (Denmark)

    Jørgensen, Kirsten; Duijm, Nijs Jan; Troen, Hanne

    2011-01-01

    ’ performance parameters continuously, it is possible to create better risk awareness on the part of employers, managers and employees. Better risk awareness by these stakeholders will make it possible to: • acknowledge and continuously control risks; • discover and manage new risks; • keep safety barriers...... into two sets of 17 “INFO-cards” or message maps, to be used by the employer and the employee, respectively. Such an INFO-card is developed for a specific group of risks and contains: • What needs to be observed, what safety barriers are in place; • What needs to be assessed, the performance parameters...

  6. Message maps for Safety Barrier Awareness

    DEFF Research Database (Denmark)

    ’ performance parameters continuously, it is possible to create better risk awareness of employers, managers and employees. Better risk awareness of these stakeholders will make it possible that: • Risks are acknowledged and controlled continuously; • New risks are discovered and managed; • Safety barriers are...... Danish DanWORM project has transferred this knowledge into two sets of 17 so-called “INFO-cards” or message maps, to be used by the employer and the employee, respectively. Such an INFO-card is developed for a specific group of risks and contains: • What needs to be observed, what safety barriers are in...

  7. THE BARRIERS OF IMPLEMENTING E-PROCUREMENT

    Directory of Open Access Journals (Sweden)

    Corina Pop Sitar

    2011-01-01

    Full Text Available The concept of e-procurement has many different meanings ranging from shopping on theinternet (through reverse auction to collaborative initiatives taking place in virtualmeetings. There are many forms of e-procurement that can be found in the literature. In thispaper we define the most important forms of e-procurement. Next, we present the mainbarriers of implementing an e-procurement found in the literature. Furthermore, we presenta matrix with the main barriers of e-procurement classified in four main categories. Finally,we elaborated for managers some guidelines in order to overcome the barriers ofimplementing e-procurement.

  8. Exploring techniques for determining fusion barrier distributions

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, J.R.; Timmers, H.; Dasgupta, M.; Hinde, D.J.; Lemmon, R.C.; Mein, J.C.; Morton, C.R.; Newton, J.O.

    1994-06-01

    Quasi-elastic scattering excitation functions, at backward angles, for reactions of {sup 16} O on {sup 92} Zr, {sup 144} Sm, {sup 154} Sm and {sup 186} W have been measured. A method for extracting barrier distributions from these data is presented. The distributions from the scattering data are compared with those from fusion, previously measured for these same reactions. All measured quasi-elastic functions decrease smoothly with energy although the rate of decrease is different for each reaction. The first differential with respect to energy of the quasi-elastic excitation function reflects the distribution of barriers for each reaction. 18 refs., 7 figs.

  9. Developments in permeable and low permeability barriers

    International Nuclear Information System (INIS)

    The concept of the reactive treatment zone whereby pollutants are attenuated as they move along a pathway in the ground has enabled a re-thinking of many of the concepts of containment. In particular it offers the potential for the control of the flux from a contaminated area by controlling the contaminant concentration in the pathway(s) as well as or instead of using a low permeability barrier. The paper outlines the basic concepts of the reactive treatment zone and the use of permeable and low permeability reactive systems. The paper then gives a case history of the installation of a permeable barrier using an in-situ reaction chamber

  10. Progress in SLIP stacking and barrier bucket

    International Nuclear Information System (INIS)

    The slip stacking for pbar production has been operational in the Main Injector(MI) since December 2004 and has increased the beam intensity on the pbar target by more than 60%. We plan to use slip stacking for the NuMI neutrino experiment to effectively increasing the beam intensity to NuMI target by about a factor two in a MI cycle. In parallel with slip stacking, we plan to study fast momentum stacking using barrier buckets. One barrier rf system has been installed and tested, and a second system is being installed during the current shutdown. (author)

  11. Logarithmic barriers for sparse matrix cones

    CERN Document Server

    Andersen, Martin S; Vandenberghe, Lieven

    2012-01-01

    Algorithms are presented for evaluating gradients and Hessians of logarithmic barrier functions for two types of convex cones: the cone of positive semidefinite matrices with a given sparsity pattern, and its dual cone, the cone of sparse matrices with the same pattern that have a positive semidefinite completion. Efficient large-scale algorithms for evaluating these barriers and their derivatives are important in interior-point methods for nonsymmetric conic formulations of sparse semidefinite programs. The algorithms are based on the multifrontal method for sparse Cholesky factorization.

  12. Permanent isolation surface barrier: Functional performance

    International Nuclear Information System (INIS)

    This document presents the functional performance parameters for permanent isolation surface barriers. Permanent isolation surface barriers have been proposed for use at the Hanford Site (and elsewhere) to isolate and dispose of certain types of waste in place. Much of the waste that would be disposed of using in-place isolation techniques is located in subsurface structures, such as solid waste burial grounds, tanks, vaults, and cribs. Unless protected in some way, the wastes could be transported to the accessible environment via transport pathways, such as water infiltration, biointrusion, wind and water erosion, human interference, and/or gaseous release

  13. Technical considerations for the implementation of subsurface microbial barriers for restoration of groundwater at UMTRA sites

    International Nuclear Information System (INIS)

    The Uranium Mill Tailings Remediation Action (UMTRA) Program is responsible for the assessment and remedial action at the 24 former uranium mill tailings sites located in the United States. The surface remediation phase, which has primarily focused on containment and stabilization of the abandoned uranium mill tailings piles, is nearing completion. Attention has now turned to the groundwater restoration phase. One alternative under consideration for groundwater restoration at UMTRA sites is the use of in-situ permeable reactive subsurface barriers. In this type of a system, contaminated groundwater will be allowed to flow naturally through a barrier filled with material which will remove hazardous constituents from the water by physical, chemical or microbial processes while allowing passage of the pore water. The subject of this report is a reactive barrier which would remove uranium and other contaminants of concern from groundwater by microbial action (i.e., a microbial barrier). The purpose of this report is to assess the current state of this technology and to determine issues that must be addressed in order to use this technology at UMTRA sites. The report focuses on six contaminants of concern at UMTRA sites including uranium, arsenic, selenium, molybdenum, cadmium and chromium. In the first section of this report, the fundamental chemical and biological processes that must occur in a microbial barrier to control the migration of contaminants are described. The second section contains a literature review of research which has been conducted on the use of microorganisms to immobilize heavy metals. The third section addresses areas which need further development before a microbial barrier can be implemented at an UMTRA site

  14. NOVEL TSUNAMI BARRIERS AND THEIR APPLICATIONS FOR HYDROELECTRIC ENERGY STORAGE, FISH FARMING, AND FOR LAND RECLAMATION

    Directory of Open Access Journals (Sweden)

    Hans J. Scheel

    2014-10-01

    Full Text Available The tsunami hazard can be mitigated if the destructive waves generated from earthquakes and landslides can be reflected by a stable submerged vertical barrier before striking coastal communities or important structures. Building such deep walls by conventional submarine technology is difficult. The present study describes the principle and the erection of such submarine defensive walls by a relatively simple efficient and economic technology. This technology is based on lowering high- strength steel fences with horizontal anchors, or two parallel steel fences with distance holders, into the sea and fixing them with rocks deposited from top. Dredged material like gravel or sand can be used for additional filling. This Tsunami-Flooding Barrier (TFB extends a few meters above sea level and carries on top a concrete supply and service road protected on both sides against storm waves by concrete walls. Replaceable surge stoppers (parapets, wave return walls prevent overtopping and erosion of the seaward barrier face. The TFBs protect the coastline against tsunami and the highest storm waves from hurricanes, but also can provide protection from oil spills or other contaminations from the ocean and thus protect flora, fauna, coral reefs and beaches. Channels and gates allow navigation and can be closed quickly upon a tsunami or storm warning. The construction costs can be eventually compensated by using the reservoirs between coast and barriers for hydroelectric energy storage (using pump-turbines in the barriers or for fish-farming, or alternatively the reservoir can be filled with rocks, rubble, gravel, sand and covered with soil in order to reclaim new land. Tidal energy can be generated by installing turbines within these barriers. Also, this submarine architecture may be applied to protect pillars of bridges and offshore platforms, and for erecting “roads” into the sea to connect near-shore platforms and wind-parks with the coast and

  15. A Technique: Generating Alternative Thoughts

    Directory of Open Access Journals (Sweden)

    Serkan AKKOYUNLU

    2013-03-01

    Full Text Available Introduction: One of the basic techniques of cognitive therapy is examination of automatic thoughts and reducing the belief in them. By employing this, we can overcome the cognitive bias apparent in mental disorders. Despite this view, according to another cognitive perspective in a given situation, there are distinct cognitive representations competing for retrieval from memory just like positive and negative schemas. In this sense generating or strengthening alternative explanations or balanced thoughts that explain the situation better than negative automatic thoughts is one of the important process goals of cognitive therapy.Objective: Aim of this review is to describe methods used to generate alternative/balanced thoughts that are used in examining automatic thoughts and also a part of automatic thought records. Alternative/balanced thoughts are the summary and end point of automatic thought work. In this text different ways including listing alternative thoughts, using examining the evidence for generating balanced thoughts, decatastrophizing in anxiety and a meta-cognitive method named two explanations are discussed. Different ways to use this technique as a homework assignment is also reviewed. Remarkable aspects of generating alternative explanations and realistic/balanced thoughts are also reviewed and exemplified using therapy transcripts. Conclusion: Generating alternative explanations and balanced thoughts are the end point and important part of therapy work on automatic thoughts. When applied properly and rehearsed as homework between sessions, these methods may lead to improvement in many mental disorders

  16. Vehicle-Barrier Tracking of a Scaled Crash Test for Roadside Barrier Design

    OpenAIRE

    Amato, Giuseppina; Ghosh, Bidisha; SIMMS, CIARAN

    2014-01-01

    In this paper the tracking system used to perform a scaled vehicle-barrier crash test is reported. The scaled crash test was performed as part of a wider project aimed at designing a new safety barrier making use of natural building materials. The scaled crash test was designed and performed as a proof of concept of the new mass-based safety barriers and the study was composed of two parts: the scaling technique and of a series of performed scaled crash tests. The scaling method was used for ...

  17. Adhesion Issues with Polymer/Oxide Barrier Coatings on Organic Displays

    Energy Technology Data Exchange (ETDEWEB)

    Matson, Dean W.; Martin, Peter M.; Graff, Gordon L.; Gross, Mark E.; Burrows, Paul E.; Bennett, Wendy D.; Hall, Michael G.; Mast, Eric S.; Bonham, Charles C.; Zumhoff, Mac R.; Rutherford, Nicole M.; Moro, Lorenza; Rosenblum, Martin; Praino, Robert F.; Visser, Robert J.

    2005-01-01

    Multilayer polymer/oxide coatings are being developed to protect sensitive organic display devices, such as OLEDs, from oxygen and water vapor permeation. The coatings have permeation levels ~ 10-6 g/m2/d for water vapor and ~10-6 cc/m2/d for oxygen, and are deposited by vacuum polymer technology. The coatings consist of either a base Al2O3 or acrylate polymer adhesion layer followed by alternating Al2O3/polymer layers. The polymer is used to decouple the 30 nm-thick Al2O3 barrier layers. Adhesion of the barrier coating to the substrate and display device is critical for the operating lifetime of the device. The substrate material could be any transparent flexible plastic. The coating technology can also be used to encapsulate organic-based electronic devices to protect them from atmospheric degradation. Plasma pretreatment is also needed for good adhesion to the substrate, but if it is too aggressive, it will damage the organic display device. We report on the effects of plasma treatment on the adhesion of barrier coatings to plastic substrates and the performance of OLED devices after plasma treatment and barrier coating deposition. We find that initial OLED performance is not significantly affected by the deposition process and plasma treatment, as demonstrated by luminosity and I-V curves.

  18. Innovation drivers and barriers in food processing

    NARCIS (Netherlands)

    Fortuin, F.T.J.M.; Omta, S.W.F.

    2009-01-01

    Purpose - The food processing industry, confronted with increased global competition and more stringent customer demands, is pressurized to improve the pace and quality of its innovation processes. This paper aims to find out what factors constitute the main drivers and barriers to innovation and to

  19. DNA nanovehicles and the biological barriers

    DEFF Research Database (Denmark)

    Okholm, Anders Hauge; Kjems, Jørgen

    2016-01-01

    modules. The applications of DNA nanostructures are still in its infancy, but one of the high expectations are to deliver solutions for targeted therapy. Nucleic acids, however, do not easily enter cells unassisted and biological barriers and harsh nucleolytic conditions in the human body must also be...

  20. Study of rotational barriers in 5-nitrosopyrimidines

    Czech Academy of Sciences Publication Activity Database

    Čechová, Lucie; Procházková, Eliška; Dračínský, Martin; Janeba, Zlatko

    Praha: Czech Chemical Society, 2015. s. 64. [Liblice 2015. Advances in Organic, Bioorganic and Pharmaceutical Chemistry /50./. 06.11.2015-08.11.2015, Olomouc] R&D Projects: GA MV VG20102015046; GA ČR GA15-11223S Institutional support: RVO:61388963 Keywords : pyrimidine * intramolecular hydrogen bonding * rotational barrier Subject RIV: CC - Organic Chemistry

  1. Tandem mirror reactor with thermal barriers

    International Nuclear Information System (INIS)

    This report gives detailed information in the form of the following chapters: (1) overview, (2) plasma physics, (3) magnets, (4) end-plug neutral beams, (5) barrier pump neutral beams, (6) ecr heating, (7) plasma direct converter, and (8) central cell

  2. Deep inelastic scattering near the Coulomb barrier

    Energy Technology Data Exchange (ETDEWEB)

    Gehring, J.; Back, B.; Chan, K. [and others

    1995-08-01

    Deep inelastic scattering was recently observed in heavy ion reactions at incident energies near and below the Coulomb barrier. Traditional models of this process are based on frictional forces and are designed to predict the features of deep inelastic processes at energies above the barrier. They cannot be applied at energies below the barrier where the nuclear overlap is small and friction is negligible. The presence of deep inelastic scattering at these energies requires a different explanation. The first observation of deep inelastic scattering near the barrier was in the systems {sup 124,112}Sn + {sup 58,64}Ni by Wolfs et al. We previously extended these measurements to the system {sup 136}Xe + {sup 64}Ni and currently measured the system {sup 124}Xe + {sup 58}Ni. We obtained better statistics, better mass and energy resolution, and more complete angular coverage in the Xe + Ni measurements. The cross sections and angular distributions are similar in all of the Sn + Ni and Xe + Ni systems. The data are currently being analyzed and compared with new theoretical calculations. They will be part of the thesis of J. Gehring.

  3. Floating convection barrier for evaporation source

    International Nuclear Information System (INIS)

    A floating matrix of titanium in an uranium evaporation source, melted by an electron beam, serves as a barrier for preventing cooler material from reaching the evaporation area. This construction allows a big volume of melted uranium to be present and new uranium to be furnished in regulated intervals without manual intervention

  4. Barrier function of the posterior capsule

    International Nuclear Information System (INIS)

    The permeability of the rabbit lens and human cataractous lens posterior capsule to epinephrine and trypan blue and the absorption of ultraviolet and visible light through the posterior capsule were studied in vitro. The posterior capsule served as a barrier to large nonelectrolytes or negative electrolytes other than trypan blue, but it did not impede epinephrine, ultraviolet or visible light

  5. Barriers to Distance Education in Rural Schools

    Science.gov (United States)

    Irvin, Matthew J.; Hannum, Wallace H.; Varre, Claire de la; Farmer, Thomas W.

    2010-01-01

    The primary purpose of the current study was to examine barriers to the use of distance education and explore related factors in small and low-income rural schools. Data were collected via a telephone survey with administrators or other qualified personnel. The sample involved 417 randomly selected small and low-income rural school districts…

  6. The Barrier within: Relational Aggression among Women

    Science.gov (United States)

    Brock, Barbara L.

    2010-01-01

    Relational aggression among women presents an overlooked barrier to women's quest for advancement in the workplace. Although research on women's leadership extols their ability to collaborate and form lasting, supportive relationships, one cannot assume that all women are supportive of other women. Research reveals that relational aggression,…

  7. DNA nanovehicles and the biological barriers

    DEFF Research Database (Denmark)

    Okholm, Anders Hauge; Kjems, Jørgen

    2016-01-01

    modules. The applications of DNA nanostructures are still in its infancy, but one of the high expectations are to deliver solutions for targeted therapy. Nucleic acids, however, do not easily enter cells unassisted and biological barriers and harsh nucleolytic conditions in the human body must also...

  8. Altered permeability barrier structure in cholesteatoma matrix

    DEFF Research Database (Denmark)

    Svane-Knudsen, Viggo; Halkier-Sørensen, Lars; Rasmussen, Gurli;

    2002-01-01

    The stratum corneum of the cholesteatoma epithelium comprises the greater part of the cholesteatoma matrix. The permeability barrier that militates against diffusion and penetration of infectious and toxic agents into and through the epithelium is situated here. The multiple long sheets of lamellar...

  9. Barrier properties of HTSC tunnel junctions

    International Nuclear Information System (INIS)

    It was found that the overall shape of the normal state tunnel conductance of metal oxides with low Fermi energies is very sensitive to the barrier height and thickness. It was shown that this curve can differ considerably from the usual tunnel characteristics known from the tunnel spectroscopy of conventional metal

  10. Computer simulations of the random barrier model

    DEFF Research Database (Denmark)

    Schrøder, Thomas; Dyre, Jeppe

    2002-01-01

    A brief review of experimental facts regarding ac electronic and ionic conduction in disordered solids is given followed by a discussion of what is perhaps the simplest realistic model, the random barrier model (symmetric hopping model). Results from large scale computer simulations are presented...

  11. Cleansing Formulations That Respect Skin Barrier Integrity

    Directory of Open Access Journals (Sweden)

    Russel M. Walters

    2012-01-01

    Full Text Available Surfactants in skin cleansers interact with the skin in several manners. In addition to the desired benefit of providing skin hygiene, surfactants also extract skin components during cleansing and remain in the stratum corneum (SC after rinsing. These side effects disrupt SC structure and degrade its barrier properties. Recent applications of vibrational spectroscopy and two-photon microscopy in skin research have provided molecular-level information to facilitate our understanding of the interaction between skin and surfactant. In the arena of commercial skin cleansers, technologies have been developed to produce cleansers that both cleanse and respect skin barrier. The main approach is to minimize surfactant interaction with skin through altering its solution properties. Recently, hydrophobically modified polymers (HMPs have been introduced to create skin compatible cleansing systems. At the presence of HMP, surfactants assemble into larger, more stable structures. These structures are less likely to penetrate the skin, thereby resulting in less aggressive cleansers and the integrity of the skin barrier is maintained. In this paper, we reviewed our recent findings on surfactant and SC interactions at molecular level and provided an overview of the HM technology for developing cleansers that respect skin barrier.

  12. Reconnaissance level study Mississippi storm surge barrier

    NARCIS (Netherlands)

    Van Ledden, M.; Lansen, A.J.; De Ridder, H.A.J.; Edge, B.

    2012-01-01

    This paper reports a reconnaissance level study of a storm surge barrier in the Mississippi River. Historical hurricanes have shown storm surge of several meters along the Mississippi River levees up to and upstream of New Orleans. Future changes due to sea level rise and subsidence will further inc

  13. Barriers to increased market-oriented activity

    DEFF Research Database (Denmark)

    Bisp, Søren

    1999-01-01

    related activities still seem to attract relatively few resources is not answered by supplying another checklist or package of facilitators. Based on published conceptual writings and empirical studies this article makes an account of what the intra-organizational barriers may be to increased market...

  14. Dielectric barrier discharge source for supersonic beams

    Energy Technology Data Exchange (ETDEWEB)

    Luria, K.; Lavie, N.; Even, U. [Sackler School of Chemistry, Tel Aviv University, Tel Aviv 69978 (Israel)

    2009-10-15

    We present a new excitation source for pulsed supersonic beams. The excitation is based on dielectric barrier discharge in the beam. It produces cold beams of metastable atoms, dissociated neutral atoms from molecular precursors, and both positive and negative ions with high efficiency and reliability.

  15. Designing and Operating a Barrier Free Campus.

    Science.gov (United States)

    Potter, Laurie S.; Potter, George T.

    An account of the Ramapo College (New Jersey) experience in the design and development of a barrier-free campus includes discussion of the academic and service problems that arise in meeting the needs of handicapped students in college. Special attention is given to: campus bathrooms, campus housing (ramps, locks, bathrooms, roommate selection,…

  16. Tacit Knowledge Barriers within Franchise Organizations

    Science.gov (United States)

    Cumberland, Denise M.; Githens, Rod P.

    2010-01-01

    This paper reviews knowledge management in the context of a franchise business operation, with a focus on tacit knowledge barriers. In a franchise organization, the transfer of knowledge occurs on multiple levels and has an added level of complexity because of the number of partners and relationships. Tacit knowledge transfer should occur…

  17. Tacit Knowledge Barriers in Franchising: Practical Solutions

    Science.gov (United States)

    Cumberland, Denise; Githens, Rod

    2012-01-01

    Purpose: The purpose of this paper is to identify barriers that hinder tacit knowledge transfer in a franchise environment and offer a compendium of solutions that encourage franchisees and franchisors to leverage tacit knowledge as a resource for competitive advantage. Design/methodology/approach: Drawing from the research on franchise…

  18. Homoepitaxial graphene tunnel barriers for spin transport

    Science.gov (United States)

    Friedman, Adam L.; van't Erve, Olaf M. J.; Robinson, Jeremy T.; Whitener, Keith E.; Jonker, Berend T.

    2016-05-01

    Tunnel barriers are key elements for both charge-and spin-based electronics, offering devices with reduced power consumption and new paradigms for information processing. Such devices require mating dissimilar materials, raising issues of heteroepitaxy, interface stability, and electronic states that severely complicate fabrication and compromise performance. Graphene is the perfect tunnel barrier. It is an insulator out-of-plane, possesses a defect-free, linear habit, and is impervious to interdiffusion. Nonetheless, true tunneling between two stacked graphene layers is not possible in environmental conditions usable for electronics applications. However, two stacked graphene layers can be decoupled using chemical functionalization. Here, we demonstrate that hydrogenation or fluorination of graphene can be used to create a tunnel barrier. We demonstrate successful tunneling by measuring non-linear IV curves and a weakly temperature dependent zero-bias resistance. We demonstrate lateral transport of spin currents in non-local spin-valve structures, and determine spin lifetimes with the non-local Hanle effect. We compare the results for hydrogenated and fluorinated tunnel and we discuss the possibility that ferromagnetic moments in the hydrogenated graphene tunnel barrier affect the spin transport of our devices.

  19. On Emotional Barriers to Second Language Learning

    Institute of Scientific and Technical Information of China (English)

    Chen Qin

    2012-01-01

    Language learning is a very complex process, which is related to many factors, either internal or external. Affective factors plays an important role in a second language learning. If only we realize such affective factors, we can overcome the emotional barriers effectively and have a successful learning.

  20. Engineered Barrier System: Physical and Chemical Environment

    International Nuclear Information System (INIS)

    The conceptual and predictive models documented in this Engineered Barrier System: Physical and Chemical Environment Model report describe the evolution of the physical and chemical conditions within the waste emplacement drifts of the repository. The modeling approaches and model output data will be used in the total system performance assessment (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. These models evaluate the range of potential water compositions within the emplacement drifts, resulting from the interaction of introduced materials and minerals in dust with water seeping into the drifts and with aqueous solutions forming by deliquescence of dust (as influenced by atmospheric conditions), and from thermal-hydrological-chemical (THC) processes in the drift. These models also consider the uncertainty and variability in water chemistry inside the drift and the compositions of introduced materials within the drift. This report develops and documents a set of process- and abstraction-level models that constitute the engineered barrier system: physical and chemical environment model. Where possible, these models use information directly from other process model reports as input, which promotes integration among process models used for total system performance assessment. Specific tasks and activities of modeling the physical and chemical environment are included in the technical work plan ''Technical Work Plan for: In-Drift Geochemistry Modeling'' (BSC 2004 [DIRS 166519]). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system analysis model reports