Science.gov

Sample records for coupling material usage

  1. Bar code usage in nuclear materials accountability

    SciTech Connect

    Mee, W.T.

    1983-07-01

    The age old method of physically taking an inventory of materials by listing each item's identification number has lived beyond its usefulness. In this age of computerization, which offers the local grocery store a quick, sure, and easy means to inventory, it is time for nuclear materials facilities to automate accountability activities. The Oak Ridge Y-12 Plant began investigating the use of automated data collection devices in 1979. At that time, bar code and optical-character-recognition (OCR) systems were reviewed with the purpose of directly entering data into DYMCAS (Dynamic Special Nuclear Materials Control and Accountability System). Both of these systems appeared applicable; however, other automated devices already employed for production control made implementing the bar code and OCR seem improbable. However, the DYMCAS was placed on line for nuclear material accountability, a decision was made to consider the bar code for physical inventory listings. For the past several months a development program has been underway to use a bar code device to collect and input data to the DYMCAS on the uranium recovery operations. Programs have been completed and tested, and are being employed to ensure that data will be compatible and useful. Bar code implementation and expansion of its use for all nuclear material inventory activity in Y-12 is presented.

  2. Bar code usage in nuclear materials accountability

    SciTech Connect

    Mee, W.T.

    1983-01-01

    The Oak Ridge Y-12 Plant began investigating the use of automated data collection devices in 1979. At this time, bar code and optical-character-recognition (OCR) systems were reviewed with the purpose of directly entering data into DYMCAS (Dynamic Special Nuclear Materials Control and Accountability System). Both of these systems appeared applicable, however, other automated devices already employed for production control made implementing the bar code and OCR seem improbable. However, the DYMCAS was placed on line for nuclear material accountability, a decision was made to consider the bar code for physical inventory listings. For the past several months a development program has been underway to use a bar code device to collect and input data to the DYMCAS on the uranium recovery operations. Programs have been completed and tested, and are being employed to ensure that data will be compatible and useful. Bar code implementation and expansion of its use for all nuclear material inventory activity in Y-12 is presented.

  3. 2011 Radioactive Materials Usage Survey for Unmonitored Point Sources

    SciTech Connect

    Sturgeon, Richard W.

    2012-06-27

    This report provides the results of the 2011 Radioactive Materials Usage Survey for Unmonitored Point Sources (RMUS), which was updated by the Environmental Protection (ENV) Division's Environmental Stewardship (ES) at Los Alamos National Laboratory (LANL). ES classifies LANL emission sources into one of four Tiers, based on the potential effective dose equivalent (PEDE) calculated for each point source. Detailed descriptions of these tiers are provided in Section 3. The usage survey is conducted annually; in odd-numbered years the survey addresses all monitored and unmonitored point sources and in even-numbered years it addresses all Tier III and various selected other sources. This graded approach was designed to ensure that the appropriate emphasis is placed on point sources that have higher potential emissions to the environment. For calendar year (CY) 2011, ES has divided the usage survey into two distinct reports, one covering the monitored point sources (to be completed later this year) and this report covering all unmonitored point sources. This usage survey includes the following release points: (1) all unmonitored sources identified in the 2010 usage survey, (2) any new release points identified through the new project review (NPR) process, and (3) other release points as designated by the Rad-NESHAP Team Leader. Data for all unmonitored point sources at LANL is stored in the survey files at ES. LANL uses this survey data to help demonstrate compliance with Clean Air Act radioactive air emissions regulations (40 CFR 61, Subpart H). The remainder of this introduction provides a brief description of the information contained in each section. Section 2 of this report describes the methods that were employed for gathering usage survey data and for calculating usage, emissions, and dose for these point sources. It also references the appropriate ES procedures for further information. Section 3 describes the RMUS and explains how the survey results are

  4. 21 CFR 211.122 - Materials examination and usage criteria.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Materials examination and usage criteria. 211.122 Section 211.122 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Packaging...

  5. 21 CFR 211.122 - Materials examination and usage criteria.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Materials examination and usage criteria. 211.122 Section 211.122 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Packaging and Labeling Control § 211.122...

  6. The composite materials handbook (MIL handbook 17). Volume 3: Materials usage, design, and analysis

    SciTech Connect

    Not Available

    1999-01-01

    The Composite Materials Handbook (MIL Handbook 17) is THE source for data and usage guidelines for current and emerging polymer matrix composite materials. It provides you with the tools you will need to design and fabricate end items from polymer matrix composite materials and offers guidelines for how these data should be generated and used. The Handbook is a comprehensive guide of composites technology and engineering, an area that is advancing and changing rapidly. Volume 3 discusses usage of the data for material procurement, quality control, design, structural analysis, and reliability. The material scope is continuous-fiber-reinforced polymer matrix composites for all applications.

  7. Lunar Regolith Simulant Materials: Recommendations for Standardization, Production, and Usage

    NASA Technical Reports Server (NTRS)

    Sibille, L.; Carpenter, P.; Schlagheck, R.; French, R. A.

    2006-01-01

    Experience gained during the Apollo program demonstrated the need for extensive testing of surface systems in relevant environments, including regolith materials similar to those encountered on the lunar surface. As NASA embarks on a return to the Moon, it is clear that the current lunar sample inventory is not only insufficient to support lunar surface technology and system development, but its scientific value is too great to be consumed by destructive studies. Every effort must be made to utilize standard simulant materials, which will allow developers to reduce the cost, development, and operational risks to surface systems. The Lunar Regolith Simulant Materials Workshop held in Huntsville, AL, on January 24 26, 2005, identified the need for widely accepted standard reference lunar simulant materials to perform research and development of technologies required for lunar operations. The workshop also established a need for a common, traceable, and repeatable process regarding the standardization, characterization, and distribution of lunar simulants. This document presents recommendations for the standardization, production and usage of lunar regolith simulant materials.

  8. A strongly coupled anyon material

    NASA Astrophysics Data System (ADS)

    Brattan, Daniel K.

    2015-11-01

    We use alternative quantisation of the D3-D5 system to explore properties of a strongly coupled anyon material at finite density and temperature. We study the transport properties of the material and find both diffusion and massive holographic zero sound modes. By studying the anyon number conductivity we also find evidence for the anyonic analogue of the metal-insulator transition.

  9. Usage of Raman DTS for wooden material analysis

    NASA Astrophysics Data System (ADS)

    Vasinek, Vladimir; Latal, Jan; Koudelka, Petr; Papes, Martin; Liner, Andrej; Rasnerova, Vladimira

    2013-05-01

    The contribution deals with a usage of Raman DTS for thermal transmittance monitoring and moisture monitoring in wooden buildings and constructions. Temperature measurement and thermal transmittance is notable for an analysis of moisture distribution inside of wooden girders that are the basic construction parts of wooden buildings during their seasoning and sanitation. In this contribution the results from measurements within real wooden objects will be presented and these results will be compared with laboratory experiments under controlled conditions. For wood sanitation two types of heating are used - flow of hot air and microwave heating. A multimode fiber 62,5/125 in primary coating is applied for measurements, this fiber is putted on the inside and outside surface of wooden construction. Here the fiber meanders are created inside of wooden girders with spacing of 1 cm. Optical fibers are laid in two mutual perpendicular cuts with usage of temperature resolution better than 0,05°C. The measured length of wooden girder is 1,4 m for unambiguously temperature specification inside the girder and its thermal transmittance. The temperature maps of various types of wooden girders are the results of analysis. Different multimode fibers with particular fiber coatings are included in the analysis. These measurements have been provided with Sentinel DTS and they are parts of a wide set DTS application for building industry. We are trying to specify the influence of fiber bending on temperature sensitivity, how to join measuring fiber to transporting fiber, critical length of both fibers and many others. Raman DTS can replace large number of thermometers and provide continuous information about temperature distribution.

  10. Materials for printed circuit boards: Past usage and future prospects

    SciTech Connect

    Lee Hong Ng; Field, F.R. III )

    1989-01-01

    This paper examines current materials utilization patterns in a major electronic materials market, printed circuit board (PCB) materials. As demands on PCB materials become more stringent, the use of high performance materials will increase. However, development of better materials is no guarantee of market success. New materials must offer an attractive price/performance combination to PCB users. A methodology to assess the competitive position of new PCB materials by combining manufacturing cost models with operations research techniques has been developed and applied to the PCB materials market. The methodology is illustrated using case studies drawn from the computers and communication industries. Results indicate that the computer industry favors high glass transition temperature materials, such as polymide and bismaleimide triazine, while the telecommunications market prefers epoxy glass for its low cost. Among the new materials targeted at high performance applications in the PCB market, cyanate ester (CE) and polytetrafluoroethylene (PTFE) have the greatest potential. PTFE is expected to fill a niche in the extremely high performance market due to its high cost and incompatibility with standard manufacturing requirements. The potential of cyanate ester, however, depends on its pricing policy and manufacturing requirements. Through the use of the PCB cost model and making some assumptions on the processing requirements of CE, it was found that almost all the price-yield combinations would make cyanate ester a viable competitor, especially in the high performance end of the market place.

  11. Usage and perceptions of phosphodiesterase type 5 inhibitors among the male partners of infertile couples

    PubMed Central

    Kim, Dong Suk; Shim, Sung Han; Lim, Jung Jin; Yang, Seung Choul

    2016-01-01

    Objective We aimed to investigate the prevalence of erectile dysfunction (ED) and the usage of phosphodiesterase type 5 (PDE5) inhibitors for ED treatment in infertile couples. Methods A total of 260 male partners in couples reporting infertility lasting at least 1 year were included in this study. In addition to an evaluation of infertility, all participants completed the International Index of Erectile Function (IIEF)-5 questionnaire to evaluate their sexual function. The participants were asked about their use of PDE5 inhibitors while trying to conceive during their partner's ovulatory period and about their concerns regarding the risks of PDE5 inhibitor use to any eventual pregnancy and/or the fetus. Results Based on the IIEF-5 questionnaire, 41.5% of the participants (108/260) were classified as having mild ED (an IIEF-5 score of 17–21), while 10.4% of the participants (27/260) had greater than mild ED (an IIEF-5 score of 16 or less). The majority (74.2%, 193/260) of male partners of infertile couples had a negative perception of the safety of using a PDE5 inhibitor while trying to conceive. Only 11.1% of men (15/135) with ED in infertile couples had used a PDE5 inhibitor when attempting conception. Conclusion ED was found to be common in the male partners of infertile couples, but the use of PDE5 inhibitors among these men was found to be very low. The majority of male partners were concerned about the risks of using PDE5 inhibitors when attempting to conceive. Appropriate counseling about this topic and treatment when necessary would likely be beneficial to infertile couples in which the male partner has ED. PMID:27104154

  12. 21 CFR 211.122 - Materials examination and usage criteria.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... materials for each different drug product, strength, dosage form, or quantity of contents shall be stored... of gang-printed labeling for different drug products, or different strengths or net contents of the... each different strength of each different drug product; (2) Use of appropriate electronic...

  13. 21 CFR 211.122 - Materials examination and usage criteria.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... materials for each different drug product, strength, dosage form, or quantity of contents shall be stored... of gang-printed labeling for different drug products, or different strengths or net contents of the... procedures: (1) Dedication of labeling and packaging lines to each different strength of each different...

  14. 21 CFR 211.122 - Materials examination and usage criteria.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... materials for each different drug product, strength, dosage form, or quantity of contents shall be stored... of gang-printed labeling for different drug products, or different strengths or net contents of the... procedures: (1) Dedication of labeling and packaging lines to each different strength of each different...

  15. Usage of scientific and technological information in developing superconducting materials

    NASA Astrophysics Data System (ADS)

    Inamura, Takahiro

    An experience of successful scientific information acquisition through the JICST File at an earliest stage of superconductivity boom, when only newspaper articles were source of information, is described. The results of the online retrieval of the JICST File told us that the crystal structure of the superconducting materials in question is K2NiF4 type, which was new information not known yet in research community in common.

  16. Usage of humic materials for formulation of stable microbial inoculants

    NASA Astrophysics Data System (ADS)

    Kydralieva, K. A.; Khudaibergenova, B. M.; Elchin, A. A.; Gorbunova, N. V.; Muratov, V. S.; Jorobekova, Sh. J.

    2009-04-01

    of the product. It is known that humic substances can increase of live organism resistance to stress loads, in particular to chemical stress, low and high temperature. Spray- and fluidized-bed drying and addition of humate-based drying protectants were evaluated for the development of dry formulations of biocontrol and plant growth promoting rhizobacteria. The drying protectants - humic acids and sodium humate gave the highest initial survival rates and the most stable formulations, without significant losses of viability after storage for 1 month at 30oC. As a result, the specific plant growth promoting effect is retained. Thus, humic materials have an unfulfilled potential for biotechnology industries based on such applications. Acknowledgement. This research was supported by the grant of ISTC KR-993.2.

  17. The usage of plastic waste as a secondary raw material for the modification of sandcrete properties

    NASA Astrophysics Data System (ADS)

    Klovas, A.; Daukšys, M.; Venčkauskas, L.

    2015-03-01

    Recently the usage of various industry wastes as a secondary raw material tends to increase its relevancy. One of possible options to decrease the amount of waste is to use them to produce new products or materials. The operation of various secondary raw materials (tire rubber, tire cord, ground glass shards, ground ceramic waste products) during the concrete mixture preparation allows to change its as well as cured concrete properties. Recently polymer and steel fibers are used for concrete reinforcement. This study analyses the usage possibility of plastic shavings for the reinforcement of concrete. The technological properties of cement slurry (sand, fraction of 0/4 and 10 kg/m3, 15 kg/m3 and 20 kg/m3 of plastic shavings) as well as mechanical, physical and porosity properties of cured sandcrete were established during the experimental research. The geometric characteristics of mill-shredded plastic shavings were established. Experimental results revealed that the usage of plastic shavings decreased slurry slump and density. The minor decrease of cured sandcrete density (~2200 kg/m3) was noticed with the addition of plastic shavings within the limits of 10 - 20 kg/m3. The flexural strength of cured sandcrete increased from 36 % to 57 % compared with reference specimen (without plastic shavings). The dependence of flexural force and deflection was obtained. Study revealed that the residual strength after crack opening is bigger with the usage of plastic shavings as a secondary raw material compared with reference specimen.

  18. Pre-Service Science and Technology Teachers' Efficacy Beliefs about Information and Communication Technologies (ICT) Usage and Material Design

    ERIC Educational Resources Information Center

    Bursal, Murat; Yigit, Nevzat

    2012-01-01

    In this study, a scale entitled "Information and Communication Technologies Usage and Material Design Efficacy [ICT_MDE]" is developed to investigate pre-service science and technology teachers' efficacy beliefs regarding ICT usage and Material Design and the factors impacting these beliefs. By using the validity and reliability data from 310…

  19. Screening of redox couples and electrode materials

    NASA Technical Reports Server (NTRS)

    Giner, J.; Swette, L.; Cahill, K.

    1976-01-01

    Electrochemical parameters of selected redox couples that might be potentially promising for application in bulk energy storage systems were investigated. This was carried out in two phases: a broad investigation of the basic characteristics and behavior of various redox couples, followed by a more limited investigation of their electrochemical performance in a redox flow reactor configuration. In the first phase of the program, eight redox couples were evaluated under a variety of conditions in terms of their exchange current densities as measured by the rotating disk electrode procedure. The second phase of the program involved the testing of four couples in a redox reactor under flow conditions with a varity of electrode materials and structures.

  20. Material Usage in High Pressure Oxygen Systems for the International Space Station

    NASA Technical Reports Server (NTRS)

    Kravchenko, Michael; Sievers, D. Elliott

    2014-01-01

    The Nitrogen/Oxygen Recharge System (NORS) for the International Space Station (ISS) Program was required as part of the Space Shuttle retirement efforts to sustain the ISS life support systems. The system is designed around a 7000 psia Oxygen or Nitrogen Recharge Tank Assembly which is able to be utilized both internally and externally to the ISS. Material selection and usage were critical to ensure oxygen compatibility for the design, while taking into consideration toxicity, weldability, brazability and general fabrication and assembly techniques. The system uses unique hardware items such a composite overwrap pressure vessel (COPV), high pressure mechanical gauges, compact regulators and valves, quick disconnects, metal tubing and flexhoses. Numerous challenges and anomalies were encountered due to the exotic nature of this project which will be discussed in detail. The knowledge gained from these anomalies and failure resolutions can be applied to more than space applications, but can also be applicable to industry pressurized systems.

  1. Quantifying exchange coupling in segregated granular materials

    NASA Astrophysics Data System (ADS)

    Morrison, C.; Saharan, L.; Ikeda, Y.; Takano, K.; Hrkac, G.; Thomson, T.

    2013-11-01

    The volume of a magnetic grain, together with its anisotropy, determines the probability of thermally activated reversal. Thus for grain volume distributions where the median volume is close to the superparamagnetic limit there will be a sub-set of grains which are either superparamagnetic on the time scale of a typical magnetic measurement (10 s), or the reverse due to magnetostatic fields from surrounding grains. We use this effect to probe exchange coupling in segregated granular materials, using CoCrPt-SiOx granular recording media as model systems. As the film thickness is reduced below 10 nm, the remanent magnetization of these films decreases, due to thermal activation and magnetostatic reversal. Varying film thickness and temperature allows us to thermally select a population of grains that contribute to the measurement. Exchange coupling is characterized by the angle dependence of remanent coercivity where we associate a breaking of symmetry from the Stoner-Wohlfarth model towards the Kondorsky model as a measure of the incoherency of reversal. Combining these models allows an estimate to be made of the volume fraction of grains that are exchange coupled and we find that, for well segregated CoCrPt-SiOx media, approximately 8% of the magnetic volume undergoes some degree of exchange coupling.

  2. Coupled improvement between thermoelectric and piezoelectric materials

    NASA Astrophysics Data System (ADS)

    Montgomery, David; Hewitt, Corey; Dun, Chaochao; Carroll, David

    A novel coupling effect in a thermoelectric and piezoelectric meta-structure is discussed. Thermo-piezoelectric generators (TPEGs) exhibit a synergistic effect that amplifies output voltage, and has been observed to increase piezoelectric voltages over 500% of initial values a time dependent thermoelectric/pyroelectric effect. The resulting improvement in voltage has been observed in carbon nanotubes as well as inorganics such as two-dimensional Bismuth Selenide platelets and Telluride nanorods thin-film thermoelectrics. TPEGs are built by integrating insulating layers of polyvinylidene fluoride (PVDF) piezoelectric films between flexible thin film p-type and n-type thermoelectrics. The physical phenomena arising in the interaction between thermoelectric and piezoelectrics is discussed and a model is presented to quantify the expected coupling voltage as a function of stress, thermal gradient, and different thermoelectric materials. TPEG are ideal to capture waste heat and vibrational energy while creating larger voltages and minimizing space when compared with similar thermoelectric or piezoelectric generators.

  3. An approach to the usage of polyethylene terephthalate (PET) waste as roadway pavement material.

    PubMed

    Gürü, Metin; Çubuk, M Kürşat; Arslan, Deniz; Farzanian, S Ali; Bilici, İbrahim

    2014-08-30

    This study investigates an application area for Polyethylene Terephthalate (PET) bottle waste which has become an environmental problem in recent decades as being a considerable part of the total plastic waste bulk. Two novel additive materials, namely Thin Liquid Polyol PET (TLPP) and Viscous Polyol PET (VPP), were chemically derived from waste PET bottles and used to modify the base asphalt separately for this aim. The effects of TLPP and VPP on the asphalt and hot mix asphalt (HMA) mixture properties were detected through conventional tests (Penetration, Softening Point, Ductility, Marshall Stability, Nicholson Stripping) and Superpave methods (Rotational Viscosity, Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR)). Also, chemical structures were described by Scanning Electron Microscope (SEM) equipped with Energy Dispersive Spectrometer (EDS) and Fourier Transform Infrared (FTIR) techniques. Since TLPP and VPP were determined to improve the low temperature performance and fatigue resistance of the asphalt as well as the Marshall Stability and stripping resistance of the HMA mixtures based on the results of the applied tests, the usage of PET waste as an asphalt roadway pavement material offers an alternative and a beneficial way of disposal of this ecologically hazardous material. PMID:25080154

  4. Thermoelectric performance of weakly coupled granular materials.

    SciTech Connect

    Glatz, A.; Beloborodov, I. S.; Materials Science Division; California State Univ. at Northridge

    2009-01-01

    We study thermoelectric properties of inhomogeneous nanogranular materials for weak tunneling conductance between the grains, g{sub t} < 1. We calculate the thermopower and figure of merit taking into account the shift of the chemical potential and the asymmetry of the density of states in the vicinity of the Fermi surface. We show that the weak coupling between the grains leads to a high thermopower and low thermal conductivity resulting in relatively high values of the figure of merit on the order of one. We estimate the temperature at which the figure of merit has its maximum value for two- and three-dimensional samples. Our results are applicable for many emerging materials, including artificially self-assembled nanoparticle arrays.

  5. Rigorous coupled wave analysis for gyrotropic materials

    NASA Astrophysics Data System (ADS)

    Onishi, Michihisa

    The goal of this study includes two targets: to extend the region of application for the modal theory, including Classical Modal Theory [CMT] and Rigorous Coupled Wave Theory [RCWT], and to investigate the convergence characteristics of CMT and RCWT. First, the RCWT algorithm for one-dimensional isotropic gratings is reviewed along with the details of its mathematical formulation, and the advantages of applying the inverse rule in the Fourier expansion are also explained. Then the CMT formulation for dielectric lamellar gratings with multiple indices and sub-periods is developed. Several numerical examples are tested and compared with the results obtained from RCWT. The convergence properties of the present CMT formulation are demonstrated with several examples and discussed in relation to the parameters used in the formulation. Next, the convergence characteristics of RCWT for continuously indexmodulated gratings are investigated. It is demonstrated that the RCWT convergence is strongly dependent on the convergence of the Fourier coefficients for the index modulation functions, and the convergence profiles of diffraction efficiencies and those of the Fourier series are closely related. Finally, the formulation of RCWT for diffraction gratings in bi-anisotropic media, which exhibit linear birefringence and/or optical activity, is developed. All of the incident, exiting and grating materials can be isotropic, uniaxial or biaxial, with or without optical activity. The principal values of the electric permittivity tensor, the magnetic permeability tensor and the gyrotropic tensor of the materials can take arbitrary values. The optical axes may be arbitrarily and independently oriented. The symmetric constitutive relations for bi-anisotropic materials are adopted. The procedures for Fourier expansion of Maxwell's equations are also described. The present RCWT formulation is implemented and applied to various problems. Diffraction efficiencies for single layer bi

  6. Uncovering Meaningful Correlation between Student Academic Performance and Library Material Usage

    ERIC Educational Resources Information Center

    Wong, Shun Han Rebekah; Webb, T. D.

    2011-01-01

    Academic libraries must demonstrate empirically that library usage does contribute positively to student academic performance and, thereby, to the university's effectiveness. While customary academic library assessment practices may not be sufficient for this purpose, the Hong Kong Baptist University (HKBU) Library undertook an experimental…

  7. Analytic Thermoelectric Couple Modeling: Variable Material Properties and Transient Operation

    NASA Technical Reports Server (NTRS)

    Mackey, Jonathan A.; Sehirlioglu, Alp; Dynys, Fred

    2015-01-01

    To gain a deeper understanding of the operation of a thermoelectric couple a set of analytic solutions have been derived for a variable material property couple and a transient couple. Using an analytic approach, as opposed to commonly used numerical techniques, results in a set of useful design guidelines. These guidelines can serve as useful starting conditions for further numerical studies, or can serve as design rules for lab built couples. The analytic modeling considers two cases and accounts for 1) material properties which vary with temperature and 2) transient operation of a couple. The variable material property case was handled by means of an asymptotic expansion, which allows for insight into the influence of temperature dependence on different material properties. The variable property work demonstrated the important fact that materials with identical average Figure of Merits can lead to different conversion efficiencies due to temperature dependence of the properties. The transient couple was investigated through a Greens function approach; several transient boundary conditions were investigated. The transient work introduces several new design considerations which are not captured by the classic steady state analysis. The work helps to assist in designing couples for optimal performance, and also helps assist in material selection.

  8. Method of processing materials using an inductively coupled plasma

    DOEpatents

    Hull, Donald E.; Bieniewski, Thomas M.

    1990-01-01

    A method for making fine power using an inductively coupled plasma. The method provides a gas-free environment, since the plasma is formed without using a gas. The starting material used in the method is in solid form.

  9. Computational methods for coupling microstructural and micromechanical materials response simulations

    SciTech Connect

    HOLM,ELIZABETH A.; BATTAILE,CORBETT C.; BUCHHEIT,THOMAS E.; FANG,HUEI ELIOT; RINTOUL,MARK DANIEL; VEDULA,VENKATA R.; GLASS,S. JILL; KNOROVSKY,GERALD A.; NEILSEN,MICHAEL K.; WELLMAN,GERALD W.; SULSKY,DEBORAH; SHEN,YU-LIN; SCHREYER,H. BUCK

    2000-04-01

    Computational materials simulations have traditionally focused on individual phenomena: grain growth, crack propagation, plastic flow, etc. However, real materials behavior results from a complex interplay between phenomena. In this project, the authors explored methods for coupling mesoscale simulations of microstructural evolution and micromechanical response. In one case, massively parallel (MP) simulations for grain evolution and microcracking in alumina stronglink materials were dynamically coupled. In the other, codes for domain coarsening and plastic deformation in CuSi braze alloys were iteratively linked. this program provided the first comparison of two promising ways to integrate mesoscale computer codes. Coupled microstructural/micromechanical codes were applied to experimentally observed microstructures for the first time. In addition to the coupled codes, this project developed a suite of new computational capabilities (PARGRAIN, GLAD, OOF, MPM, polycrystal plasticity, front tracking). The problem of plasticity length scale in continuum calculations was recognized and a solution strategy was developed. The simulations were experimentally validated on stockpile materials.

  10. Materials science. Materials that couple sensing, actuation, computation, and communication.

    PubMed

    McEvoy, M A; Correll, N

    2015-03-20

    Tightly integrating sensing, actuation, and computation into composites could enable a new generation of truly smart material systems that can change their appearance and shape autonomously. Applications for such materials include airfoils that change their aerodynamic profile, vehicles with camouflage abilities, bridges that detect and repair damage, or robotic skins and prosthetics with a realistic sense of touch. Although integrating sensors and actuators into composites is becoming increasingly common, the opportunities afforded by embedded computation have only been marginally explored. Here, the key challenge is the gap between the continuous physics of materials and the discrete mathematics of computation. Bridging this gap requires a fundamental understanding of the constituents of such robotic materials and the distributed algorithms and controls that make these structures smart. PMID:25792332

  11. Transfer having a coupling coefficient higher than its active material

    NASA Technical Reports Server (NTRS)

    Lesieutre, George A. (Inventor); Davis, Christopher L. (Inventor)

    2001-01-01

    A coupling coefficient is a measure of the effectiveness with which a shape-changing material (or a device employing such a material) converts the energy in an imposed signal to useful mechanical energy. Device coupling coefficients are properties of the device and, although related to the material coupling coefficients, are generally different from them. This invention describes a class of devices wherein the apparent coupling coefficient can, in principle, approach 1.0, corresponding to perfect electromechanical energy conversion. The key feature of this class of devices is the use of destabilizing mechanical pre-loads to counter inherent stiffness. The approach is illustrated for piezoelectric and thermoelectrically actuated devices. The invention provides a way to simultaneously increase both displacement and force, distinguishing it from alternatives such as motion amplification, and allows transducer designers to achieve substantial performance gains for actuator and sensor devices.

  12. Method of processing materials using an inductively coupled plasma

    DOEpatents

    Hull, Donald E.; Bieniewski, Thomas M.

    1989-01-01

    A method for coating surfaces or implanting ions in an object using an inductively coupled plasma. The method provides a gas-free environment, since the plasma is formed without using a gas. The coating material or implantation material is intitially in solid form.

  13. Usage Automata

    NASA Astrophysics Data System (ADS)

    Bartoletti, Massimo

    Usage automata are an extension of finite stata automata, with some additional features (e.g. parameters and guards) that improve their expressivity. Usage automata are expressive enough to model security requirements of real-world applications; at the same time, they are simple enough to be statically amenable, e.g. they can be model-checked against abstractions of program usages. We study here some foundational aspects of usage automata. In particular, we discuss about their expressive power, and about their effective use in run-time mechanisms for enforcing usage policies.

  14. Advanced thermoplastic composites: An attractive new material for usage in highly loaded vehicle components

    SciTech Connect

    Mehn, R.; Seidl, F.; Peis, R.; Heinzmann, D.; Frei, P.

    1995-10-01

    Beside the lightweight potential and further well known advantages of advanced composite materials, continuous fiber reinforced thermoplastics employed in vehicle structural parts especially offer short manufacturing cycle times and an additional economically viable manufacturing process. Presenting a frame structure concept for two highly loaded vehicle parts, a safety seat and a side door, numerous features concerning the choice of suitable composite materials, design aspects, investigations to develop a thermoforming technique, mature for a series production of vehicle parts, are discussed.

  15. Review of air-coupled ultrasonic materials characterization.

    PubMed

    Chimenti, D E

    2014-09-01

    This article presents a review of air-coupled ultrasonics employed in the characterization or nondestructive inspection of industrial materials. Developments in air-coupled transduction and electronics are briefly treated, although the emphasis here is on methods of characterization and inspection, and in overcoming limitations inherent in the use of such a tenuous sound coupling medium as air. The role of Lamb waves in plate characterization is covered, including the use of air-coupled acoustic beams to measure the elastic and/or viscoelastic properties of a material. Air-coupled acoustic detection, when other methods are employed to generate high-amplitude sound beams is also reviewed. Applications to civil engineering, acoustic tomography, and the characterization of both paper and wood are dealt with here. A brief summary of developments in air-coupled acoustic arrays and the application of air-coupled methods in nonlinear ultrasonics complete the review. In particular, the work of Professor Bernard Hosten and his collaborators at Bordeaux is carefully examined. PMID:24650685

  16. Simplified Language Materials--Their Usage and Value to Teachers and Support Staff in Mainstream Settings

    ERIC Educational Resources Information Center

    Rix, Jonathan

    2006-01-01

    This paper examines the current use of simplified language materials (SLMs) by teachers and support staff across England. Drawing on a survey of Primary and Secondary schools it identifies the degree to which teachers and support staff use and produce SLMs. It explores both the contradictions and similarities between practitioners' perceptions of…

  17. Usage induced changes to surface topography and material properties in polysilicon MEMS electrothermal structures

    NASA Astrophysics Data System (ADS)

    Oak, Sahil; Ramachandran, Gautham; Dallas, Tim

    2012-03-01

    This paper presents the results of an experimental study of electrothermal poly-Si MEMS structures wherein changes to the surface topography and material properties are observed due to use. The ex-situ AFM characterization reveals changes in the surface topography after cyclic actuation. The extent of topical SiO2 appears to increase with the number of actuation cycles and increasing stress levels on the polysilicon surfaces. The differences in the surface topography and oxide thickness are characterized as a function of fatigue cycling and in-situ annealing of the electrothermal actuators. FEA analyses were performed to evaluate the magnitude and distribution of stresses in the actuators to compare stress effects from oxide development on electrothermomechanical structures. With the observation of topographical changes, the intrinsic material property like resistivity was also affected. A change of 1.4% was seen for a 20% duty cycle, 3.1% for 50% duty cycle and 4.1% for 80% duty cycle. Similar experiments were performed for sealed devices in order to observe the changes in resistivity under inert conditions. A comparison of change in resistivity for sealed devices and nonsealed devices was done. Finally, force-distance curves were plotted to ascertain the adhesion forces for the actuator surfaces before and after actuation. The adhesion forces increases from ~7nN (un-actuated chevron) to ~40nN (10,000 cycles).

  18. Numerical and Experimental Analysis on Inorganic Phase Change Material Usage in Construction

    NASA Astrophysics Data System (ADS)

    Muthuvel, S.; Saravanasankar, S.; Sudhakarapandian, R.; Muthukannan, M.

    2014-12-01

    This work demonstrates the significance of Phase Change Material (PCM) in the construction of working sheds and product storage magazines in fireworks industries to maintain less temperature variation by passive cooling. The inorganic PCM, namely Calcium Chloride Hexahydrate (CCH) is selected in this study. First, the performance of two models with inbuilt CCH was analysed, using computational fluid dynamics. A significant change in the variation of inner wall temperature was observed, particularly during the working hours. This is mainly due to passive cooling, where the heat transfer from the surroundings to the room is partially used for the phase change from solid to liquid. The experiment was carried out by constructing two models, one with PCM packed in hollow brick walls and roof, and the other one as a conventional construction. The experimental results show that the temperature of the room got significantly reduced up to 7 °C. The experimental analysis results had good agreement with the numerical analysis results, and this reveals the advantage of the PCM in the fireworks industry construction.

  19. Water Based Inkjet Material Deposition Of Donor-Acceptor Nanoparticles For Usage In Organic Photovoltaics

    NASA Astrophysics Data System (ADS)

    Penmetcha, Anirudh Raju

    Significant efficiency increases are being made for bulk heterojunction organic photovoltaic prototype devices with world records at 11%. However the chlorinated solvents most frequently used in prototype manufacture would cause local health and safety concerns or large scale environmental pollution upon expansion of these techniques for commercialization. Moreover, research to bridge prototype and large-scale production of these solar cells is still in its infancy. Most prototype devices are made in inert glove box environments using spin-coating. There is a need to develop a non-toxic ink and incorporate it into a material deposition system that can be used in mass production. In this thesis, P3HT:PCBM organic photovoltaic devices were fabricated with the help of inkjet printing. P3HT:PCBM blends were dissolved in organic solvent systems, and this solution was used as the ink for the printer. The "coffee-ring effect" as well as the effect of inkjet printing parameters on film formation were highlighted - thus the inkjet printing method was validated as a stepping stone between lab-scale production of OPVs and large-scale roll-to-roll manufacturing. To address the need of a non-toxic ink, P3HT:PCBM blends were then dispersed in water, using the miniemulsion method. The nanoparticles were characterized for their size, as well as the blending between the P3HT and PCBM within the nanoparticle. These dispersions were then converted into inks. Finally, these nanoparticle inks were inkjet-printed to fabricate OPV devices. Based on the results obtained here, tentative "next steps" have been outlined in order to improve upon this research work, in the future.

  20. Method of processing materials using an inductively coupled plasma

    DOEpatents

    Hull, D.E.; Bieniewski, T.M.

    1987-04-13

    A method of processing materials. The invention enables ultrafine, ultrapure powders to be formed from solid ingots in a gas free environment. A plasma is formed directly from an ingot which insures purity. The vaporized material is expanded through a nozzle and the resultant powder settles on a cold surface. An inductively coupled plasma may also be used to process waste chemicals. Noxious chemicals are directed through a series of plasma tubes, breaking molecular bonds and resulting in relatively harmless atomic constituents. 3 figs.

  1. Coupling of exothermic and endothermic hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Brooks, Kriston P.; Bowden, Mark E.; Karkamkar, Abhijeet J.; Houghton, Adrian Y.; Autrey, S. Thomas

    2016-08-01

    Chemical hydrogen storage (CHS) materials are a high-storage-density alternative to the gaseous compressed hydrogen currently used to provide hydrogen for fuel cell vehicles. One of the challenges of CHS materials is addressing the energy barriers required to break the chemical bonds and release the hydrogen. Coupling CHS reactions that are endothermic and exothermic during dehydrogenation can improve onboard energy efficiency and thermal control for the system, making such materials viable. Acceptable coupling between reactions requires both thermodynamic and kinetic considerations. In this work, models were developed to predict the reaction enthalpy and rate required to achieve high conversions for both reactions based on experimental measurements. Modeling results show that the coupling efficiency of exothermic and endothermic reactions is more sensitive to the ratio of the exothermic and endothermic enthalpies than to the ratio of the rates of the two steps. Modeling results also show that a slower endothermic step rate is desirable to permit sufficient heating of the reactor by the exothermic step. We look at two examples of a sequential and parallel reaction scheme and provide some of the first published insight into the required temperature range to maximize the hydrogen release from 1,2-BN cyclohexane and indoline.

  2. Strongly coupled inorganic/nanocarbon hybrid materials for advanced electrocatalysis.

    PubMed

    Liang, Yongye; Li, Yanguang; Wang, Hailiang; Dai, Hongjie

    2013-02-13

    Electrochemical systems, such as fuel cell and water splitting devices, represent some of the most efficient and environmentally friendly technologies for energy conversion and storage. Electrocatalysts play key roles in the chemical processes but often limit the performance of the entire systems due to insufficient activity, lifetime, or high cost. It has been a long-standing challenge to develop efficient and durable electrocatalysts at low cost. In this Perspective, we present our recent efforts in developing strongly coupled inorganic/nanocarbon hybrid materials to improve the electrocatalytic activities and stability of inorganic metal oxides, hydroxides, sulfides, and metal-nitrogen complexes. The hybrid materials are synthesized by direct nucleation, growth, and anchoring of inorganic nanomaterials on the functional groups of oxidized nanocarbon substrates including graphene and carbon nanotubes. This approach affords strong chemical attachment and electrical coupling between the electrocatalytic nanoparticles and nanocarbon, leading to nonprecious metal-based electrocatalysts with improved activity and durability for the oxygen reduction reaction for fuel cells and chlor-alkali catalysis, oxygen evolution reaction, and hydrogen evolution reaction. X-ray absorption near-edge structure and scanning transmission electron microscopy are employed to characterize the hybrids materials and reveal the coupling effects between inorganic nanomaterials and nanocarbon substrates. Z-contrast imaging and electron energy loss spectroscopy at single atom level are performed to investigate the nature of catalytic sites on ultrathin graphene sheets. Nanocarbon-based hybrid materials may present new opportunities for the development of electrocatalysts meeting the requirements of activity, durability, and cost for large-scale electrochemical applications. PMID:23339685

  3. Coupled transport/hyperelastic model for nastic materials

    NASA Astrophysics Data System (ADS)

    Homison, Chris; Weiland, Lisa M.

    2006-03-01

    Nastic materials are high energy density active materials that mimic processes used in the plant kingdom to produce large deformations through the conversion of chemical energy. These materials utilize the controlled transport of charge and fluid across a selectively-permeable membrane to achieve bulk deformation in a process referred to in the plant kingdom as nastic movements. The nastic material being developed consists of synthetic membranes containing biological ion pumps, ion channels, and ion exchangers surrounding fluid-filled cavities embedded within a polymer matrix. In this paper the formulation of a biological transport model and its coupling with a hyperelastic finite element model of the polymer matrix is discussed. The transport model includes contributions from ion pumps, ion exchangers, and solvent flux. This work will form the basis for a feedback loop in material synthesis efforts. The goal of these studies is to determine the relative importance of the various parameters associated with both the polymer matrix and the biological transport components.

  4. Coupled hydromechanical and electromagnetic disturbances in unsaturated porous materials

    PubMed Central

    Revil, A; Mahardika, H

    2013-01-01

    A theory of cross-coupled flow equations in unsaturated soils is necessary to predict (1) electroosmotic flow with application to electroremediation and agriculture, (2) the electroseismic and the seismoelectric effects to develop new geophysical methods to characterize the vadose zone, and (3) the streaming current, which can be used to investigate remotely ground water flow in unsaturated conditions in the capillary water regime. To develop such a theory, the cross-coupled generalized Darcy and Ohm constitutive equations of transport are extended to unsaturated conditions. This model accounts for inertial effects and for the polarization of porous materials. Rather than using the zeta potential, like in conventional theories for the saturated case, the key parameter used here is the quasi-static volumetric charge density of the pore space, which can be directly computed from the quasi-static permeability. The apparent permeability entering Darcy's law is also frequency dependent with a critical relaxation time that is, in turn, dependent on saturation. A decrease of saturation increases the associated relaxation frequency. The final form of the equations couples the Maxwell equations and a simplified form of two-fluid phases Biot theory accounting for water saturation. A generalized expression of the Richard equation is derived, accounting for the effect of the vibration of the skeleton during the passage of seismic waves and the electrical field. A new expression is obtained for the effective stress tensor. The model is tested against experimental data regarding the saturation and frequency dependence of the streaming potential coupling coefficient. The model is also adapted for two-phase flow conditions and a numerical application is shown for water flooding of a nonaqueous phase liquid (NAPL, oil) contaminated aquifer. Seismoelectric conversions are mostly taking place at the NAPL (oil)/water encroachment front and can be therefore used to remotely track the

  5. Coupled hydromechanical and electromagnetic disturbances in unsaturated porous materials.

    PubMed

    Revil, A; Mahardika, H

    2013-02-01

    A theory of cross-coupled flow equations in unsaturated soils is necessary to predict (1) electroosmotic flow with application to electroremediation and agriculture, (2) the electroseismic and the seismoelectric effects to develop new geophysical methods to characterize the vadose zone, and (3) the streaming current, which can be used to investigate remotely ground water flow in unsaturated conditions in the capillary water regime. To develop such a theory, the cross-coupled generalized Darcy and Ohm constitutive equations of transport are extended to unsaturated conditions. This model accounts for inertial effects and for the polarization of porous materials. Rather than using the zeta potential, like in conventional theories for the saturated case, the key parameter used here is the quasi-static volumetric charge density of the pore space, which can be directly computed from the quasi-static permeability. The apparent permeability entering Darcy's law is also frequency dependent with a critical relaxation time that is, in turn, dependent on saturation. A decrease of saturation increases the associated relaxation frequency. The final form of the equations couples the Maxwell equations and a simplified form of two-fluid phases Biot theory accounting for water saturation. A generalized expression of the Richard equation is derived, accounting for the effect of the vibration of the skeleton during the passage of seismic waves and the electrical field. A new expression is obtained for the effective stress tensor. The model is tested against experimental data regarding the saturation and frequency dependence of the streaming potential coupling coefficient. The model is also adapted for two-phase flow conditions and a numerical application is shown for water flooding of a nonaqueous phase liquid (NAPL, oil) contaminated aquifer. Seismoelectric conversions are mostly taking place at the NAPL (oil)/water encroachment front and can be therefore used to remotely track the

  6. Microflow liquid chromatography coupled to mass spectrometry--an approach to significantly increase sensitivity, decrease matrix effects, and reduce organic solvent usage in pesticide residue analysis.

    PubMed

    Uclés Moreno, Ana; Herrera López, Sonia; Reichert, Barbara; Lozano Fernández, Ana; Hernando Guil, María Dolores; Fernández-Alba, Amadeo Rodríguez

    2015-01-20

    This manuscript reports a new pesticide residue analysis method employing a microflow-liquid chromatography system coupled to a triple quadrupole mass spectrometer (microflow-LC-ESI-QqQ-MS). This uses an electrospray ionization source with a narrow tip emitter to generate smaller droplets. A validation study was undertaken to establish performance characteristics for this new approach on 90 pesticide residues, including their degradation products, in three commodities (tomato, pepper, and orange). The significant benefits of the microflow-LC-MS/MS-based method were a high sensitivity gain and a notable reduction in matrix effects delivered by a dilution of the sample (up to 30-fold); this is as a result of competition reduction between the matrix compounds and analytes for charge during ionization. Overall robustness and a capability to withstand long analytical runs using the microflow-LC-MS system have been demonstrated (for 100 consecutive injections without any maintenance being required). Quality controls based on the results of internal standards added at the samples' extraction, dilution, and injection steps were also satisfactory. The LOQ values were mostly 5 μg kg(-1) for almost all pesticide residues. Other benefits were a substantial reduction in solvent usage and waste disposal as well as a decrease in the run-time. The method was successfully applied in the routine analysis of 50 fruit and vegetable samples labeled as organically produced. PMID:25495653

  7. Experimental identification of smart material coupling effects in composite structures

    NASA Astrophysics Data System (ADS)

    Chesne, S.; Jean-Mistral, C.; Gaudiller, L.

    2013-07-01

    Smart composite structures have an enormous potential for industrial applications, in terms of mass reduction, high material resistance and flexibility. The correct characterization of these complex structures is essential for active vibration control or structural health monitoring applications. The identification process generally calls for the determination of a generalized electromechanical coupling coefficient. As this process can in practice be difficult to implement, an original approach, presented in this paper, has been developed for the identification of the coupling effects of a smart material used in a composite curved beam. The accuracy of the proposed identification technique is tested by applying active modal control to the beam, using a reduced model based on this identification. The studied structure was as close to reality as possible, and made use of integrated transducers, low-cost sensors, clamped boundary conditions and substantial, complex excitation sources. PVDF (polyvinylidene fluoride) and MFC (macrofiber composite) transducers were integrated into the composite structure, to ensure their protection from environmental damage. The experimental identification described here was based on a curve fitting approach combined with the reduced model. It allowed a reliable, powerful modal control system to be built, controlling two modes of the structure. A linear quadratic Gaussian algorithm was used to determine the modal controller-observer gains. The selected modes were found to have an attenuation as strong as -13 dB in experiments, revealing the effectiveness of this method. In this study a generalized approach is proposed, which can be extended to most complex or composite industrial structures when they are subjected to vibration.

  8. Mechanical coupling for a rotor shaft assembly of dissimilar materials

    DOEpatents

    Shi, Jun; Bombara, David; Green, Kevin E.; Bird, Connic; Holowczak, John

    2009-05-05

    A mechanical coupling for coupling a ceramic disc member to a metallic shaft includes a first wedge clamp and a second wedge clamp. A fastener engages a threaded end of a tie-bolt to sandwich the ceramic disc between the wedge clamps. An axial spring is positioned between the fastener and the second wedge clamp to apply an axial preload along the longitudinal axis. Another coupling utilizes a rotor shaft end of a metallic rotor shaft as one wedge clamp. Still another coupling includes a solid ceramic rotor disc with a multiple of tie-bolts radially displaced from the longitudinal axis to exert the preload on the solid ceramic rotor disc.

  9. Giant and universal magnetoelectric coupling in soft materials and concomitant ramifications for materials science and biology.

    PubMed

    Liu, Liping; Sharma, Pradeep

    2013-10-01

    Magnetoelectric coupling-the ability of a material to magnetize upon application of an electric field and, conversely, to polarize under the action of a magnetic field-is rare and restricted to a rather small set of exotic hard crystalline materials. Intense research activity has recently ensued on materials development, fundamental scientific issues, and applications related to this phenomenon. This tantalizing property, if present in adequate strength at room temperature, can be used to pave the way for next-generation memory devices such as miniature magnetic random access memories and multiple state memory bits, sensors, energy harvesting, spintronics, among others. In this Rapid Communication, we prove the existence of an overlooked strain mediated nonlinear mechanism that can be used to universally induce the giant magnetoelectric effect in all (sufficiently) soft dielectric materials. For soft polymer foams-which, for instance, may be used in stretchable electronics-we predict room-temperature magnetoelectric coefficients that are comparable to the best known (hard) composite materials created. We also argue, based on a simple quantitative model, that magnetoreception in some biological contexts (e.g., birds) most likely utilizes this very mechanism. PMID:24229099

  10. The use of real or complex coupling coefficients for lossy piezoelectric materials.

    PubMed

    Piquette, Jean C; McLaughlin, Elizabeth A

    2009-04-01

    Two competing approaches for calculating coupling coefficients for lossy piezoelectric materials, one producing a real result and the other a complex result, are compared and analyzed. It is found that the complex coupling coefficient suffers from mathematical difficulties, which the real coupling coefficient does not exhibit. Moreover, it is pointed out that a prediction made by the complex coupling coefficient theory conflicts with experiment while the corresponding real coupling coefficient theory prediction does not. When a coupling coefficient of interest has been computed from the real coupling coefficient theory using piezoelectric equations having intensive independent variables, the resulting expression has the same algebraic form as the corresponding static coupling coefficient formula. Moreover, only the real parts of the piezoelectric, elastic, and dielectric material properties appear. PMID:19406711

  11. Production and application of chemical fibers with special properties for manufacturing composite materials and goods of different usage

    NASA Technical Reports Server (NTRS)

    Levit, R.

    1993-01-01

    The development of modern technologies demands the creation of new nonmetallic, fibrous materials with specific properties. The fibers and materials developed by NII 'Chimvolokno', St. Petersburg, can be divided into two groups. The first group includes heat-resistant fibers, fire-resistant fibers, thermotropic fibers, fibers for medical application, and textile structures. The second group contains refractory fibers, chemoresistant and antifriction fibers, fibers on the basis of polyvinyl alcohol, microfiltering films, and paperlike and nonwoven materials. In cooperation with NPO 'Chimvolokno' MYTITSHI, we developed and started producing heat-resistant high-strength fibers on the base of polyhetarearilin and aromatic polyimides (SVM and terlon); heat-resistant fibers on the base of polyemede (aramid); fire-retardant fibers (togilen); chemoresistant and antifriction fibers on the basis of homo and copolymers of polytetrafluoroethylene (polyfen and ftorin); and water soluble, acetylated, and high-modulus fibers from polyvinyl alcohol (vylen). Separate reports will deal with textile structures and thermotropic fibers, as well as with medical fibers. One of the groups of refractory fibers carbon fibers (CF) and the corresponding paperlike nonwoven materials are discussed in detail. Also, composite materials (CM) and their base, which is the subject of the author's research since 1968, is discussed.

  12. Social Ecology and Social Behavior: The Development of the Differential Usage of Play Materials in Preschool Children.

    ERIC Educational Resources Information Center

    Patterson, Diane Scott

    A series of three studies investigated the role of play materials in supporting social interactions of nursery school children. Subjects were 14 boys and 11 girls, 4 and 5 years of age, who came from a variety of socioeconomic and racial backgrounds. Observations were made for 16 days, during the free play hour at each of four play centers: art,…

  13. On the thermomechanical coupling in dissipative materials: A variational approach for generalized standard materials

    NASA Astrophysics Data System (ADS)

    Bartels, A.; Bartel, T.; Canadija, M.; Mosler, J.

    2015-09-01

    This paper deals with the thermomechanical coupling in dissipative materials. The focus lies on finite strain plasticity theory and the temperature increase resulting from plastic deformation. For this type of problem, two fundamentally different modeling approaches can be found in the literature: (a) models based on thermodynamical considerations and (b) models based on the so-called Taylor-Quinney factor. While a naive straightforward implementation of thermodynamically consistent approaches usually leads to an over-prediction of the temperature increase due to plastic deformation, models relying on the Taylor-Quinney factor often violate fundamental physical principles such as the first and the second law of thermodynamics. In this paper, a thermodynamically consistent framework is elaborated which indeed allows the realistic prediction of the temperature evolution. In contrast to previously proposed frameworks, it is based on a fully three-dimensional, finite strain setting and it naturally covers coupled isotropic and kinematic hardening - also based on non-associative evolution equations. Considering a variationally consistent description based on incremental energy minimization, it is shown that the aforementioned problem (thermodynamical consistency and a realistic temperature prediction) is essentially equivalent to correctly defining the decomposition of the total energy into stored and dissipative parts. Interestingly, this decomposition shows strong analogies to the Taylor-Quinney factor. In this respect, the Taylor-Quinney factor can be well motivated from a physical point of view. Furthermore, certain intervals for this factor can be derived in order to guarantee that fundamental physically principles are fulfilled a priori. Representative examples demonstrate the predictive capabilities of the final constitutive modeling framework.

  14. A loosely-coupled scheme for the interaction between a fluid, elastic structure and poroelastic material

    NASA Astrophysics Data System (ADS)

    Bukač, M.

    2016-05-01

    We model the interaction between an incompressible, viscous fluid, thin elastic structure and a poroelastic material. The poroelastic material is modeled using the Biot's equations of dynamic poroelasticity. The fluid, elastic structure and the poroelastic material are fully coupled, giving rise to a nonlinear, moving boundary problem with novel energy estimates. We present a modular, loosely coupled scheme where the original problem is split into the fluid sub-problem, elastic structure sub-problem and poroelasticity sub-problem. An energy estimate associated with the stability of the scheme is derived in the case where one of the coupling parameters, β, is equal to zero. We present numerical tests where we investigate the effects of the material properties of the poroelastic medium on the fluid flow. Our findings indicate that the flow patterns highly depend on the storativity of the poroelastic material and cannot be captured by considering fluid-structure interaction only.

  15. Variations in Battery Life of a Heart—Lung Machine Using Different Pump Speeds, Pressure Loads, Boot Material, Centrifugal Pump Head, Multiple Pump Usage, and Battery Age

    PubMed Central

    Marshall, Cornelius; Hargrove, Martin; O’Donnell, Aonghus; Aherne, Thomas

    2005-01-01

    Abstract: Electrical failure during cardiopulmonary bypass (CPB) has previously been reported to occur in 1 of every 1500 cases. Most heart—lung machine pump consoles are equipped with built-in battery back-up units. Battery run times of these devices are variable and have not been reported. Different conditions of use can extend battery life in the event of electrical failure. This study was designed to examine the run time of a fully charged battery under various conditions of pump speed, pressure loads, pump boot material, multiple pump usage, and battery life. Battery life using a centrifugal pump also was examined. The results of this study show that battery life is affected by pump speed, circuit pressure, boot stiffness, and the number of pumps in service. Centrifugal pumps also show a reduced drain on battery when compared with roller pumps. These elements affect the longevity and performance of the battery. This information could be of value to the individual during power failure as these are variables that can affect the battery life during such a challenging scenario. PMID:16350380

  16. Quantitative Probes of Electron-Phonon Coupling in an Organic Charge-Transfer Material

    NASA Astrophysics Data System (ADS)

    Rury, Aaron; Sorenson, Shayne; Driscoll, Eric; Dawlaty, Jahan

    While organic charge transfer (CT) materials may provide alternatives to inorganic materials in electronics and photonics applications, properties central to applications remain understudied in these organic materials. Specifically, electron-phonon coupling plays a pivotal role in electronic applications yet this coupling in CT materials remains difficult to directly characterize. To better understand the suitability of organic CT materials for electronic applications, we have devised an experimental technique that can directly assess electron-phonon coupling in a model organic CT material. Upon non-resonant interaction with an ultrafast laser pulse, we show that coherent excitation of Raman-active lattice vibrations of quinhydrone, a 1:1 co-crystal of the hydroquinone and p-benzoquinone, modulates the energies of electronic transitions probed by a white light pulse. Using a well-established theoretical framework of vibrational quantum beat spectra across the probe bandwidth, we quantitatively extract the parameters describing these electronic transitions to characterize electron-phonon coupling in this material. In conjunction with temperature-dependent resonance Raman measurements, we assess the hypothesis that several sharp transitions in the near-IR correspond to previously unknown excitonic states of this material. These results and their interpretation set the foundation for further elucidation of the one of the most important parameters in the application of organic charge-transfer materials to electronics and photonics.

  17. Achieving synchronization with active hybrid materials: Coupling self-oscillating gels and piezoelectric films

    NASA Astrophysics Data System (ADS)

    Yashin, Victor V.; Levitan, Steven P.; Balazs, Anna C.

    2015-06-01

    Lightweight, deformable materials that can sense and respond to human touch and motion can be the basis of future wearable computers, where the material itself will be capable of performing computations. To facilitate the creation of “materials that compute”, we draw from two emerging modalities for computation: chemical computing, which relies on reaction-diffusion mechanisms to perform operations, and oscillatory computing, which performs pattern recognition through synchronization of coupled oscillators. Chemical computing systems, however, suffer from the fact that the reacting species are coupled only locally; the coupling is limited by diffusion as the chemical waves propagate throughout the system. Additionally, oscillatory computing systems have not utilized a potentially wearable material. To address both these limitations, we develop the first model for coupling self-oscillating polymer gels to a piezoelectric (PZ) micro-electro-mechanical system (MEMS). The resulting transduction between chemo-mechanical and electrical energy creates signals that can be propagated quickly over long distances and thus, permits remote, non-diffusively coupled oscillators to communicate and synchronize. Moreover, the oscillators can be organized into arbitrary topologies because the electrical connections lift the limitations of diffusive coupling. Using our model, we predict the synchronization behavior that can be used for computational tasks, ultimately enabling “materials that compute”.

  18. Achieving synchronization with active hybrid materials: Coupling self-oscillating gels and piezoelectric films

    PubMed Central

    Yashin, Victor V.; Levitan, Steven P.; Balazs, Anna C.

    2015-01-01

    Lightweight, deformable materials that can sense and respond to human touch and motion can be the basis of future wearable computers, where the material itself will be capable of performing computations. To facilitate the creation of “materials that compute”, we draw from two emerging modalities for computation: chemical computing, which relies on reaction-diffusion mechanisms to perform operations, and oscillatory computing, which performs pattern recognition through synchronization of coupled oscillators. Chemical computing systems, however, suffer from the fact that the reacting species are coupled only locally; the coupling is limited by diffusion as the chemical waves propagate throughout the system. Additionally, oscillatory computing systems have not utilized a potentially wearable material. To address both these limitations, we develop the first model for coupling self-oscillating polymer gels to a piezoelectric (PZ) micro-electro-mechanical system (MEMS). The resulting transduction between chemo-mechanical and electrical energy creates signals that can be propagated quickly over long distances and thus, permits remote, non-diffusively coupled oscillators to communicate and synchronize. Moreover, the oscillators can be organized into arbitrary topologies because the electrical connections lift the limitations of diffusive coupling. Using our model, we predict the synchronization behavior that can be used for computational tasks, ultimately enabling “materials that compute”. PMID:26105979

  19. COUPLING

    DOEpatents

    Hawke, B.C.

    1963-02-26

    This patent relates to a releasable coupling connecting a control rod to a control rod drive. This remotely operable coupling mechanism can connect two elements which are laterally and angviarly misaligned, and provides a means for sensing the locked condition of the elements. The coupling utilizes a spherical bayonet joint which is locked against rotation by a ball detent lock. (AEC)

  20. Air-coupled ultrasonic investigation of multi-layered composite materials.

    PubMed

    Kazys, R; Demcenko, A; Zukauskas, E; Mazeika, L

    2006-12-22

    Air-coupled ultrasonics is fine alternative for the immersion testing technique. Usually a through transmission and a pitch-catch arrangement of ultrasonic transducers are used. The pitch-catch arrangement is very attractive for non-destructive testing and evaluation of materials, because it allows one-side access to the object. However, this technique has several disadvantages. It is sensitive to specularly reflected and edge waves. A spatial resolution depends on a distance between the transducers. A new method for detection and visualisation of inhomogeneities in composite materials using one-side access air-coupled ultrasonic measurement technique is described. Numerical predictions of Lamb wave interaction with a defect in a composite material are carried out and the interaction mechanism is explained. Experimental measurements are carried out with different arrangements of the transducers. The proposed method enables detect delamination and impact type defects in honeycomb materials. PMID:16797664

  1. Warm Forming of Aluminum Alloys using a Coupled Thermo-Mechanical Anisotropic Material Model

    SciTech Connect

    Abedrabbo, Nader; Pourboghrat, Farhang; Carsley, John E.

    2005-08-05

    Temperature-dependant anisotropic material models for two types of automotive aluminum alloys (5754-O and 5182-O) were developed and implemented in LS-Dyna as a user material subroutine (UMAT) for coupled thermo-mechanical finite element analysis (FEA) of warm forming of aluminum alloys. The anisotropy coefficients of the Barlat YLD2000 plane stress yield function for both materials were calculated for the range of temperatures 25 deg. C-260 deg. C. Curve fitting was used to calculate the anisotropy coefficients of YLD2000 and the flow stress as a function of temperature. This temperature-dependent material model was successfully applied to the coupled thermo-mechanical analysis of stretching of aluminum sheets and results were compared with experiments.

  2. Warm Forming of Aluminum Alloys using a Coupled Thermo-Mechanical Anisotropic Material Model

    NASA Astrophysics Data System (ADS)

    Abedrabbo, Nader; Pourboghrat, Farhang; Carsley, John E.

    2005-08-01

    Temperature-dependant anisotropic material models for two types of automotive aluminum alloys (5754-O and 5182-O) were developed and implemented in LS-Dyna as a user material subroutine (UMAT) for coupled thermo-mechanical finite element analysis (FEA) of warm forming of aluminum alloys. The anisotropy coefficients of the Barlat YLD2000 plane stress yield function for both materials were calculated for the range of temperatures 25°C-260°C. Curve fitting was used to calculate the anisotropy coefficients of YLD2000 and the flow stress as a function of temperature. This temperature-dependent material model was successfully applied to the coupled thermo-mechanical analysis of stretching of aluminum sheets and results were compared with experiments.

  3. Computational simulation of coupled material degradation processes for probabilistic lifetime strength of aerospace materials

    NASA Technical Reports Server (NTRS)

    Boyce, Lola; Bast, Callie C.

    1992-01-01

    The research included ongoing development of methodology that provides probabilistic lifetime strength of aerospace materials via computational simulation. A probabilistic material strength degradation model, in the form of a randomized multifactor interaction equation, is postulated for strength degradation of structural components of aerospace propulsion systems subjected to a number of effects or primative variables. These primative variable may include high temperature, fatigue or creep. In most cases, strength is reduced as a result of the action of a variable. This multifactor interaction strength degradation equation has been randomized and is included in the computer program, PROMISS. Also included in the research is the development of methodology to calibrate the above described constitutive equation using actual experimental materials data together with linear regression of that data, thereby predicting values for the empirical material constraints for each effect or primative variable. This regression methodology is included in the computer program, PROMISC. Actual experimental materials data were obtained from the open literature for materials typically of interest to those studying aerospace propulsion system components. Material data for Inconel 718 was analyzed using the developed methodology.

  4. Giant and universal magnetoelectric coupling in soft materials and concomitant ramifications for materials science and biology

    NASA Astrophysics Data System (ADS)

    Liu, Liping; Sharma, Pradeep

    2013-10-01

    Magnetoelectric coupling—the ability of a material to magnetize upon application of an electric field and, conversely, to polarize under the action of a magnetic field—is rare and restricted to a rather small set of exotic hard crystalline materials. Intense research activity has recently ensued on materials development, fundamental scientific issues, and applications related to this phenomenon. This tantalizing property, if present in adequate strength at room temperature, can be used to pave the way for next-generation memory devices such as miniature magnetic random access memories and multiple state memory bits, sensors, energy harvesting, spintronics, among others. In this Rapid Communication, we prove the existence of an overlooked strain mediated nonlinear mechanism that can be used to universally induce the giant magnetoelectric effect in all (sufficiently) soft dielectric materials. For soft polymer foams—which, for instance, may be used in stretchable electronics—we predict room-temperature magnetoelectric coefficients that are comparable to the best known (hard) composite materials created. We also argue, based on a simple quantitative model, that magnetoreception in some biological contexts (e.g., birds) most likely utilizes this very mechanism.

  5. Modelling of the evaporation behaviour of particulate material for slurry nebulization inductively coupled plasma atomic emission spectrometry

    NASA Astrophysics Data System (ADS)

    Merten, D.; Heitland, P.; Broekaert, J. A. C.

    1997-11-01

    This paper is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta, Part B (SAB). This hardcopy text, comprising the main body and an appendix, is accompanied by a disk with programs, data files and a brief manual. The main body discusses purpose, design principle and usage of the computer software for modelling the evaporation behaviour of particles in inductively coupled plasma atomic emission spectrometry (ICP-AES). Computer software has been developed in FORTRAN 77 language in order to simulate the evaporation behaviour of particles of refractory materials such as encountered in the analysis of advanced ceramic powders by slurry nebulization inductively coupled argon plasma atomic spectrometry. The program simulates the evaporation of single particles in the inductively coupled plasma and also enable it to calculate on the base of a given particle size distribution the evaporation behaviour of all the particles contained in a sample. In a so-called "intensity concept", the intensity is calculated as a function of the observation height in order to determine recovery rates for slurries compared with aqueous solutions. This yields a quick insight whether a calibration with aqueous solutions can be used for analysis of slurries of a given powder by slurry nebulization ICP-AES and also is a help in determining the optimal parameters for analyses of powders by means of slurry nebulization ICP-AES. Applications for the evaporation of Al 2O 3 and SiC powders document the usefulness of the model for the case of a 1.5 kW argon ICP of which the temperature at 8 mm above the load coil has been determined to be 6100 K. The model predicts the maximum particle size for SiC and Al 2O 3 that can be transported (10-15 μm) and evaporated for a given efficiency under given experimental conditions. For both Al 2O 3 and SiC, two ceramic powders of different grain size were investigated. The median particle sizes cover

  6. AGRICULTURAL CHEMICAL USAGE DATA

    EPA Science Inventory

    This report, which summarizes the use of agricultural chemicals is issued by the National Agricultural Statistics Service (NASS) as part of its series on Agricultural Chemical Usage. Other publications in the series present statistics for on-farm agricultural chemical usage for f...

  7. Ligand coupling symmetry correlates with thermopower enhancement in small-molecule/nanocrystal hybrid materials.

    PubMed

    Lynch, Jared; Kotiuga, Michele; Doan-Nguyen, Vicky V T; Queen, Wendy L; Forster, Jason D; Schlitz, Ruth A; Murray, Christopher B; Neaton, Jeffrey B; Chabinyc, Michael L; Urban, Jeffrey J

    2014-10-28

    We investigate the impact of the coupling symmetry and chemical nature of organic-inorganic interfaces on thermoelectric transport in Cu2-xSe nanocrystal thin films. By coupling ligand-exchange techniques with layer-by-layer assembly methods, we are able to systematically vary nanocrystal-organic linker interfaces, demonstrating how the functionality of the polar headgroup and the coupling symmetry of the organic linkers can change the power factor (S(2)σ) by nearly 2 orders of magnitude. Remarkably, we observe that ligand-coupling symmetry has a profound effect on thermoelectric transport in these hybrid materials. We shed light on these results using intuition from a simplified model for interparticle charge transport via tunneling through the frontier orbital of a bound ligand. Our analysis indicates that ligand-coupling symmetry and binding mechanisms correlate with enhanced conductivity approaching 2000 S/cm, and we employ this concept to demonstrate among the highest power factors measured for quantum-dot based thermoelectric inorganic-organic composite materials of ∼ 30 μW/m · K(2). PMID:25211028

  8. COUPLING

    DOEpatents

    Frisch, E.; Johnson, C.G.

    1962-05-15

    A detachable coupling arrangement is described which provides for varying the length of the handle of a tool used in relatively narrow channels. The arrangement consists of mating the key and keyhole formations in the cooperating handle sections. (AEC)

  9. Efficient coupling of light to graphene plasmons by compressing surface polaritons with tapered bulk materials.

    PubMed

    Nikitin, A Yu; Alonso-González, P; Hillenbrand, R

    2014-05-14

    Graphene plasmons promise exciting nanophotonic and optoelectronic applications. Owing to their extremely short wavelengths, however, the efficient coupling of photons to propagating graphene plasmons-critical for the development of future devices-can be challenging. Here, we propose and numerically demonstrate coupling between infrared photons and graphene plasmons by the compression of surface polaritons on tapered bulk slabs of both polar and doped semiconductor materials. Propagation of surface phonon polaritons (in SiC) and surface plasmon polaritons (in n-GaAs) along the tapered slabs compresses the polariton wavelengths from several micrometers to around 200 nm, which perfectly matches the wavelengths of graphene plasmons. The proposed coupling device allows for a 25% conversion of the incident energy into graphene plasmons and, therefore, could become an efficient route toward graphene plasmon circuitry. PMID:24773123

  10. Influence of coupling substances in the measurement of ultrasound velocity in stone materials

    NASA Astrophysics Data System (ADS)

    Giuzio, Beatrice; Alvarez de Buergo, Monica; Fort, Rafael; Masini, Nicola

    2015-04-01

    Ultrasonic (US) testing is widely applied in many fields (i.e. aviation, petrochemical, power engineering, construction and metallurgical industries). In the field of built cultural heritage and science conservation, US testing can provide the quality of the historic building materials (physic-mechanical properties), their heterogeneity/homogeinity and anisotropy, in terms of materials characterization, but also how deterioration processes can affect their quality (either after natural decay or simulation ageing tests in the laboratory). Moreover, US testing is a useful technique in evaluating the effectiveness of conservation and restoration techniques such as assessing the compatibility among original and restoration materials, identification of original quarries, and the success or not in the increase of a material cohesion when applying consolidating products. In order to obtain precise, real and reliable measurements, coupling substances between the material surface and the ultrasonic sensors are frequently used, to provide a proper contact between the transducer and the material, to assure the perfect transmission of the ultrasonic wave. Various coupling agents can be applied for this purpose. According to Wesolowski (2012), the choice of the coupling agent significantly affects the measurement of propagation velocity in material samples and, as a consequence, the US test results. In this paper, the effect of six coupling agents (medical gel used for ultrasonography, gel + parafilm, plasticine, honey, glicerine and a plastic material provided for ultrasound measurement by Panametrics) on ultrasonic measurements conducted on specific building materials is investigated on two different types of building stones (granite and dolostone from the area of Madrid, traditionally used in the construction of the built heritage, 4 stone specimens for each rock variety, 20 x 6 x 8 cm). Direct and indirect modes measuring were performed, the first one with the transducers

  11. Enhancing Inter-phase Exchange Coupling in SmCo5/Co Nanocomposite Materials

    NASA Astrophysics Data System (ADS)

    Wu, Dangxin; Zhang, Qiming; Liu, J. P.

    2006-10-01

    Exchange-coupled hard/soft phase nanocomposite magnets were proposed to increase the maximum energy product by combining the large anisotropy of hard phase materials and the high saturation magnetization of soft phase materials. To understand the inter-phase exchange coupling is very important for design of nanocomposite magnets. In this work, we performed first-principles calculations to investigate the inter-phase exchange coupling between hard phase SmCo5 and soft phase Co using superlattice model. The calculations were based on Density Functional Theory, using projector augmented wave (PAW) method and linear-muffin-tin-orbital (LMTO) method in the atomic sphere approximation. The atomic structures were optimized and the electronic ground state was obtained. Then the noncollinear magnetic calculations were performed to calculate the exchange interactions. We found that the total energy is a quadratic function of angle (θ) between the directions of magnetic moments of hard phase and middle layer of soft phase. We found that Fe doped soft phase strengths the exchange coupling between SmCo5/Co in our models, which in turn may lead to higher maximum energy product.

  12. A one-dimension coupled hysteresis model for giant magnetostrictive materials

    NASA Astrophysics Data System (ADS)

    Zheng, Xiaojing; Sun, Le

    2007-02-01

    This paper addresses the development of a one-dimension model for quantifying magnetic-elastic-thermal coupling and hysteresis inherent to giant magnetostrictive materials. Firstly, the anhysteretic law is modeled by considering the Gibbs free energy function G( σ, M, T), and thermodynamic relations are used to obtain the constitutive expressions. These expressions character the effects of coupling between stress, magnetization, and temperature in the giant magnetostrictive material but hysteresis, i.e. strain and magnetic intensity described by above the constitutive expressions are single-valued function of the magnetization. And then pinning is incorporated to describe hysteresis based on Jiles-Atherton model. The model considered in the paper is demonstrated valid by comparing the predicted results with experimental data. Moreover, the model proposed in the paper is convenient to be used in engineering applications since the parameters referred to the model have definite physical mean and can all be easily determined by experiments.

  13. Determination of trace metals in marine biological reference materials by inductively coupled plasma mass spectrometry

    SciTech Connect

    Beauchemin, D.; McLaren, J.W.; Willie, S.N.; Berman, S.S.

    1988-04-01

    Inductively coupled plasma mass spectrometry (ICP-MS) was used for the analysis of two marine biological reference materials (dogfish liver tissue (DOLT-1) and dogfish muscle tissue (DORM-1)). The materials were put into solution by digestion in a nitric acid/hydrogen peroxide mixture. Thirteen elements (Na, Mg, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Cd, Hg, and Pb) were then determined. Accurate results were obtained by standard additions or isotope dilution techniques for all of these elements in DORM-1 and for all but Cr in DOLT-1.

  14. Some aspects of coupled electrical-mechanical effects in dielectric materials

    NASA Astrophysics Data System (ADS)

    Teyssedre, Gilbert; Berquez, Laurent; Laurent, Christian

    2015-05-01

    The propensity of electrically insulating materials to generate/store electrical charges leads to a panel of electromechanical phenomena that can be either exploited in applications relevant to electrical engineering, or represent limitations in the performance of insulating materials. The aim of this contribution is to describe various features of these electrical-mechanical coupling phenomena with focus on the field-induced strain measurement of charged polymers, on the charge distribution measurement by pulsed electroacoustic method and on the contribution of electromechanical effects in electrical ageing phenomena. Contribution to the topical issue "Electrical Engineering Symposium (SGE 2014)", edited by Adel Razek

  15. A general one-dimension nonlinear magneto-elastic coupled constitutive model for magnetostrictive materials

    SciTech Connect

    Zhang, Da-Guang; Li, Meng-Han; Zhou, Hao-Miao

    2015-10-15

    For magnetostrictive rods under combined axial pre-stress and magnetic field, a general one-dimension nonlinear magneto-elastic coupled constitutive model was built in this paper. First, the elastic Gibbs free energy was expanded into polynomial, and the relationship between stress and strain and the relationship between magnetization and magnetic field with the polynomial form were obtained with the help of thermodynamic relations. Then according to microscopic magneto-elastic coupling mechanism and some physical facts of magnetostrictive materials, a nonlinear magneto-elastic constitutive with concise form was obtained when the relations of nonlinear strain and magnetization in the polynomial constitutive were instead with transcendental functions. The comparisons between the prediction and the experimental data of different magnetostrictive materials, such as Terfenol-D, Metglas and Ni showed that the predicted magnetostrictive strain and magnetization curves were consistent with experimental results under different pre-stresses whether in the region of low and moderate field or high field. Moreover, the model can fully reflect the nonlinear magneto-mechanical coupling characteristics between magnetic, magnetostriction and elasticity, and it can effectively predict the changes of material parameters with pre-stress and bias field, which is useful in practical applications.

  16. Performance of tonpilz transducers with segmented piezoelectric stacks using materials with high electromechanical coupling coefficient.

    PubMed

    Thompson, Stephen C; Meyer, Richard J; Markley, Douglas C

    2014-01-01

    Tonpilz acoustic transducers for use underwater often include a stack of piezoelectric material pieces polarized along the length of the stack and having alternating polarity. The pieces are interspersed with electrodes, bonded together, and electrically connected in parallel. The stack is normally much shorter than a quarter wavelength at the fundamental resonance frequency so that the mechanical behavior of the transducer is not affected by the segmentation. When the transducer bandwidth is less than a half octave, as has conventionally been the case, for example, with lead zirconate titanate (PZT) material, stack segmentation has no significant effect on the mechanical behavior of the device in its normal operating band near the fundamental resonance. However, when a high coupling coefficient material such as lead magnesium niobate-lead titanate (PMN-PT) is used to achieve a wider bandwidth with the tonpilz, the performance difference between a segmented stack and a similar piezoelectric section with electrodes only at the two ends can be significant. This paper investigates the effects of stack segmentation on the performance of wideband underwater tonpilz acoustic transducers. Included is a discussion of a particular tonpilz transducer design using single crystal piezoelectric material with high coupling coefficient compared with a similar design using more traditional PZT ceramics. PMID:24437755

  17. Cellular polypropylene polymer foam as air-coupled ultrasonic transducer materials.

    PubMed

    Satyanarayan, L; Haberman, Michael R; Berthelot, Yves H

    2010-10-01

    Cellular polypropylene polymer foams, also known as ferroelectrets, are compelling candidates for air-coupled ultrasonic transducer materials because of their excellent acoustic impedance match to air and because they have a piezoelectric d(33) coefficient superior to that of PVDF. This study investigates the performance of ferroelectret transducers in the generation and reception of ultrasonic waves in air. As previous studies have noted, the piezoelectric coupling coefficients of these foams depend on the number, size, and distribution of charged voids in the microstructure. The present work studies the influence of these parameters both theoretically and experimentally. First, a three-dimensional model is employed to explain the variation of piezoelectric coupling coefficients, elastic stiffness, and dielectric permittivity as a function of void fraction based on void-scale physics and void geometry. Laser Doppler vibrometer (LDV) measurements of the effective d(33) coefficient of a specially fabricated prototype transmitting transducer are then shown which clearly indicate that the charged voids in the ferroelectret material are randomly distributed in the plane of the foam. The frequency-dependent dynamic d(33) coefficient is then reported from 50 to 500 kHz for different excitation voltages and shown to be largely insensitive to drive voltage. Lastly, two ferroelectret transducers are operated in transmit-receive mode and the received signal is shown to accurately represent the corresponding signal generated by the transmitting transducer as measured using LDV. PMID:20889422

  18. Thermal and Chemical Characterization of Non-metallic Materials Using Coupled Thermogravimetric Analysis and Infrared Spectroscopy

    NASA Technical Reports Server (NTRS)

    Huff, Timothy L.; Griffin, Dennis E. (Technical Monitor)

    2001-01-01

    Thermogravimetric analysis (TGA) is widely employed in the thermal characterization of non-metallic materials, yielding valuable information on decomposition characteristics of a sample over a wide temperature range. However, a potential wealth of chemical information is lost during the process, with the evolving gases generated during thermal decomposition escaping through the exhaust line. Fourier Transform-Infrared spectroscopy (FT-IR) is a powerful analytical technique for determining many chemical constituents while in any material state, in this application, the gas phase. By linking these two techniques, evolving gases generated during the TGA process are directed into an appropriately equipped infrared spectrometer for chemical speciation. Consequently, both thermal decomposition and chemical characterization of a material may be obtained in a single sample run. In practice, a heated transfer line is employed to connect the two instruments while a purge gas stream directs the evolving gases into the FT-IR, The purge gas can be either high purity air or an inert gas such as nitrogen to allow oxidative and pyrolytic processes to be examined, respectively. The FT-IR data is collected real-time, allowing continuous monitoring of chemical compositional changes over the course of thermal decomposition. Using this coupled technique, an array of diverse materials has been examined, including composites, plastics, rubber, fiberglass epoxy resins, polycarbonates, silicones, lubricants and fluorocarbon materials. The benefit of combining these two methodologies is of particular importance in the aerospace community, where newly developing materials have little available data with which to refer. By providing both thermal and chemical data simultaneously, a more definitive and comprehensive characterization of the material is possible. Additionally, this procedure has been found to be a viable screening technique for certain materials, with the generated data useful in

  19. Thermal and Chemical Characterization of Non-Metallic Materials Using Coupled Thermogravimetric Analysis and Infrared Spectroscopy

    NASA Technical Reports Server (NTRS)

    Huff, Timothy L.

    2002-01-01

    Thermogravimetric analysis (TGA) is widely employed in the thermal characterization of non-metallic materials, yielding valuable information on decomposition characteristics of a sample over a wide temperature range. However, a potential wealth of chemical information is lost during the process, with the evolving gases generated during thermal decomposition escaping through the exhaust line. Fourier Transform-Infrared spectroscopy (FT-IR) is a powerful analytical technique for determining many chemical constituents while in any material state, in this application, the gas phase. By linking these two techniques, evolving gases generated during the TGA process are directed into an appropriately equipped infrared spectrometer for chemical speciation. Consequently, both thermal decomposition and chemical characterization of a material may be obtained in a single sample run. In practice, a heated transfer line is employed to connect the two instruments while a purge gas stream directs the evolving gases into the FT-IR. The purge gas can be either high purity air or an inert gas such as nitrogen to allow oxidative and pyrolytic processes to be examined, respectively. The FT-IR data is collected realtime, allowing continuous monitoring of chemical compositional changes over the course of thermal decomposition. Using this coupled technique, an array of diverse materials has been examined, including composites, plastics, rubber, fiberglass epoxy resins, polycarbonates, silicones, lubricants and fluorocarbon materials. The benefit of combining these two methodologies is of particular importance in the aerospace community, where newly developing materials have little available data with which to refer. By providing both thermal and chemical data simultaneously, a more definitive and comprehensive characterization of the material is possible. Additionally, this procedure has been found to be a viable screening technique for certain materials, with the generated data useful in

  20. Multidimensional fully-coupled thermal/chemical/mechanical response of reactive materials

    SciTech Connect

    Hobbs, M.L.; Baer, M.R.

    1995-11-01

    A summary of multidimensional modeling is presented which describes coupled thermals chemical and mechanical response of reactive and nonreactive materials. This modeling addresses cookoff of energetic material (EM) prior to the onset of ignition. Cookoff, lasting from seconds to days, sensitizes the EM whereupon combustion of confined, degraded material determines the level of violence. Such processes are dynamic, occurring over time scales of millisecond to microsecond, and thus more amenable for shock physics analysis. This work provides preignition state estimates such as the amount of decomposition, morphological changes, and quasistatic stress states for subsequent dynamic analysis. To demonstrate a fully-coupled thermal/chemical/quasistatic mechanical capability, several example simulations have been performed: (1) the one-dimensional time-to-explosion experiments, (2) the Naval Air Weapon Center`s (NAWC) small scale cookoff bomb, (3) a small hot cell experiment and (4) a rigid, highly porous, closed-cell polyurethane foam. Predictions compared adequately to available data. Deficiencies in the model and future directions are discussed.

  1. Soft X-ray Shock Loading and Momentum Coupling in Meteorite and Planetary Materials^1

    NASA Astrophysics Data System (ADS)

    Remo, J. L.; Furnish, M. D.; Lawrence, R. J.

    2011-06-01

    X-ray momentum coupling coefficients, CM, for planetary materials were determined by measuring stress waveforms produced by impulsive radiation loading from the SNL Z- machine. Targets were iron and stone meteorites, solid and powdered dunite, and Si, Al, and Fe. All samples were ˜ 1 mm thick and, except for Si, backed by LiF single-crystal windows. The x-ray spectra included thermal radiation (blackbody 170 to 237 eV) and line emissions from the pinch material (Cu, Ni, Al, or stainless steel). Target fluences of 0.4 to 1.7 kJ/cm^2 at intensities 43 to 260 GW/cm^2 produced front surface plasma pressures of 2.6 to 12.4 GPa. Stress waves driven into the samples were attenuating due to the short (˜ 5 ns) duration of the drive pulse. CM was determined using the fact that an attenuating wave impulse is constant, and accounted for the mechanical impedance mismatch between samples and window. Related experiments in the literature are discussed. Values ranged from 0.8 to 3.1 x 10-5 s/m. CTH hydrocode modeling of x-ray coupling to porous and fully dense silica supported the experimental measurements and extrapolations to other materials. ^1 Work supported by Sandia National Labs, operated by Sandia Corp., a wholly owned subsidiary of Lockheed Martin Corp., for the U.S. DOE's NNSA under contract DE-AC04-94AL85000.

  2. Possible existence of a new type of left-handed materials in coupled ferromagnetic bilayer films

    NASA Astrophysics Data System (ADS)

    Chen, Jiangwei; Zhang, Baoshan; Tang, Dongming; Yang, Yi; Xu, Weidong; Lu, Huaixian

    2006-07-01

    On the basis of Landau-Lifshitz-Gilbert (LLG) equation, an anomalous ferromagnetic resonance behavior is demonstrated in detail. Coupling between the magnetic moments produces a 3 π/2 phase delay for one of the moments ferromagnetic resonance unusually, thus leads the sign of magnetic susceptibility χ˜=χ'-jχ″ to be opposite to that induced by the usual ferromagnetic resonance. Consequently, a left-handed material (LHM) may be formed near the low-frequency side of the resonance. Particularly, a LHM with negative value of real part of permeability only is predicted.

  3. Production date determination of uranium-oxide materials by inductively coupled plasma mass spectrometry.

    PubMed

    Varga, Zsolt; Surányi, Gergely

    2007-09-01

    The paper describes analytical methods developed for the production date determination of uranium-based nuclear materials by the measurement of 230Th/234U isotope ratio. An improved sample preparation method for the destructive analysis involving extraction chromatographic separation with TEVA resin was applied prior to the measurement by isotope dilution inductively coupled plasma sector field mass spectrometry (ICP-SFMS). The results obtained were compared with the direct, quasi-non-destructive measurement using laser ablation ICP-SFMS technique for age determination. The advantages and limitations of both methods are discussed. PMID:17765059

  4. Design of a Protection Thermal Energy Storage Using Phase Change Material Coupled to a Solar Receiver

    NASA Astrophysics Data System (ADS)

    Verdier, D.; Falcoz, Q.; Ferrière, A.

    2014-12-01

    Thermal Energy Storage (TES) is the key for a stable electricity production in future Concentrated Solar Power (CSP) plants. This work presents a study on the thermal protection of the central receiver of CSP plant using a tower which is subject to considerable thermal stresses in case of cloudy events. The very high temperatures, 800 °C at design point, impose the use of special materials which are able to resist at high temperature and high mechanical constraints and high level of concentrated solar flux. In this paper we investigate a TES coupling a metallic matrix drilled with tubes of Phase Change Material (PCM) in order to store a large amount of thermal energy and release it in a short time. A numerical model is developed to optimize the arrangement of tubes into the TES. Then a methodology is given, based from the need in terms of thermal capacity, in order to help the choice of the geometry.

  5. Achieving synchronization with active hybrid materials: Coupling self-oscillating gels and piezoelectric films

    NASA Astrophysics Data System (ADS)

    Yashin, Victor V.; Levitan, Steven P.; Balazs, Anna C.

    Our goal is to develop materials that compute by using non-linear oscillating chemical reactions to perform spatio-temporal recognition tasks. The material of choice is a polymer gel undergoing the oscillatory Belousov-Zhabotinsky reaction. The novelty of our approach is in employing hybrid gel-piezoelectric micro-electro-mechanical systems (MEMS) to couple local chemo-mechanical oscillations over long distances by electrical connection. Our modeling revealed that (1) interaction between the MEMS units is sufficiently strong for synchronization; (2) the mode of synchronization depends on the number of units, type of circuit connection (serial of parallel), and polarity of the units; (3) each mode has a distinctive pattern in phase of oscillations and generated voltage. The results indicate feasibility of using the hybrid gel-piezoelectric MEMS for oscillator based unconventional computing.

  6. Coupled heat transfer model and experiment study of semitransparent barrier materials in aerothermal environment

    NASA Astrophysics Data System (ADS)

    Wang, Da-Lin; Qi, Hong

    Semi-transparent materials (such as IR optical windows) are widely used for heat protection or transfer, temperature and image measurement, and safety in energy , space, military, and information technology applications. They are used, for instance, ceramic coatings for thermal barriers of spacecrafts or gas turbine blades, and thermal image observation under extreme or some dangerous environments. In this paper, the coupled conduction and radiation heat transfer model is established to describe temperature distribution of semitransparent thermal barrier medium within the aerothermal environment. In order to investigate this numerical model, one semi-transparent sample with black coating was considered, and photothermal properties were measured. At last, Finite Volume Method (FVM) was used to solve the coupled model, and the temperature responses from the sample surfaces were obtained. In addition, experiment study was also taken into account. In the present experiment, aerodynamic heat flux was simulated by one electrical heater, and two experiment cases were designed in terms of the duration of aerodynamic heating. One case is that the heater irradiates one surface of the sample continually until the other surface temperature up to constant, and the other case is that the heater works only 130 s. The surface temperature responses of these two cases were recorded. Finally, FVM model of the coupling conduction-radiation heat transfer was validated based on the experiment study with relative error less than 5%.

  7. Determination of the rare-earth elements in geological materials by inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Lichte, F.E.; Meier, A.L.; Crock, J.G.

    1987-01-01

    A method of analysis of geological materials for the determination of the rare-earth elements using the Inductively coupled plasma mass spectrometric technique (ICP-MS) has been developed. Instrumental parameters and factors affecting analytical results have been first studied and then optimized. Samples are analyzed directly following an acid digestion, without the need for separation or preconcentration with limits of detection of 2-11 ng/g, precision of ?? 2.5% relative standard deviation, and accuracy comparable to inductively coupled plasma emission spectrometry and instrumental neutron activation analysis. A commercially available ICP-MS instrument is used with modifications to the sample introduction system, torch, and sampler orifice to reduce the effects of high salt content of sample solutions prepared from geologic materials. Corrections for isobaric interferences from oxide ions and other diatomic and triatomic ions are made mathematically. Special internal standard procedures are used to compensate for drift in metahmetal oxide ratios and sensitivity. Reference standard values are used to verify the accuracy and utility of the method.

  8. An Investigation on the Coupled Thermal-Mechanical-Electrical Response of Automobile Thermoelectric Materials and Devices

    NASA Astrophysics Data System (ADS)

    Chen, Gang; Mu, Yu; Zhai, Pengcheng; Li, Guodong; Zhang, Qingjie

    2013-07-01

    Thermoelectric (TE) materials, which can directly convert heat to electrical energy, possess wide application potential for power generation from waste heat. As TE devices in vehicle exhaust power generation systems work in the long term in a service environment with coupled thermal-mechanical-electrical conditions, the reliability of their mechanical strength and conversion efficiency is an important issue for their commercial application. Based on semiconductor TE devices wih multiple p- n couples and the working environment of a vehicle exhaust power generation system, the service conditions of the TE devices are simulated by using the finite-element method. The working temperature on the hot side is set according to experimental measurements, and two cooling methods, i.e., an independent and shared water tank, are adopted on the cold side. The conversion efficiency and thermal stresses of the TE devices are calculated and discussed. Numerical results are obtained, and the mechanism of the influence on the conversion efficiency and mechanical properties of the TE materials is revealed, aiming to provide theoretical guidance for optimization of the design and commercial application of vehicle TE devices.

  9. Nonlinear optics of hybrid nano-materials under strong coupling conditions

    NASA Astrophysics Data System (ADS)

    Sukharev, Maxim

    2014-03-01

    Modern optics fueled with both tremendous advances in nano-fabrication and laser physics is currently experiencing significant growth. We are presently witnessing a unique situation - the research centered at interaction of matter with electromagnetic radiation is fully diving into nanoscale, where one considers purely quantum systems optically driven by nano-materials. The possibilities are vast ranging from fundamental ideas on single atom/molecule optical manipulation, through control of light far below the diffraction limit, to optical engineering and photonic circuitry. Despite progress, the research in optics of quantum media coupled to nano- materials is not complete. Many recent works consider just several quantum emitters driven by near-fields altered by plasmonic materials with a few very promising attempts to include collective effects, which as I will show in this talk play a pivotal role in quantum optics of nano-materials. I will discuss general concepts of nano- plasmonics (one of the most promising sub-fields of nano-optics) with several examples ranging from linear spectroscopy to nonlinear transient absorption.

  10. Laser-material interactions: A study of laser energy coupling with solids

    SciTech Connect

    Shannon, M A

    1993-11-01

    This study of laser-light interactions with solid materials ranges from low-temperature heating to explosive, plasma-forming reactions. Contained are four works concerning laser-energy coupling: laser (i) heating and (ii) melting monitored using a mirage effect technique, (iii) the mechanical stress-power generated during high-powered laser ablation, and (iv) plasma-shielding. First, a photothermal deflection (PTD) technique is presented for monitoring heat transfer during modulated laser heating of opaque solids that have not undergone phase-change. Of main interest is the physical significance of the shape, magnitude, and phase for the temporal profile of the deflection signal. Considered are the effects that thermophysical properties, boundary conditions, and geometry of the target and optical probe-beam have on the deflection response. PTD is shown to monitor spatial and temporal changes in heat flux leaving the surface due to changes in laser energy coupling. The PTD technique is then extended to detect phase-change at the surface of a solid target. Experimental data shows the onset of melt for indium and tin targets. The conditions for which melt can be detected by PTD is analyzed in terms of geometry, incident power and pulse length, and thermophysical properties of the target and surroundings. Next, monitoring high-powered laser ablation of materials with stress-power is introduced. The motivation for considering stress-power is given, followed by a theoretical discussion of stress-power and how it is determined experimentally. Experiments are presented for the ablation of aluminum targets as a function of energy and intensity. The stress-power response is analyzed for its physical significance. Lastly, the influence of plasma-shielding during high-powered pulsed laser-material interactions is considered. Crater size, emission, and stress-power are measured to determine the role that the gas medium and laser pulse length have on plasma shielding.

  11. Flexible diaphragm-extreme temperature usage

    NASA Technical Reports Server (NTRS)

    Lerma, Guillermo (Inventor)

    1991-01-01

    A diaphragm suitable for extreme temperature usage, such as encountered in critical aerospace applications, is fabricated by a unique method, and of a unique combination of materials. The materials include multilayered lay-ups of diaphragm materials sandwiched between layers of bleeder fabrics. After being formed in the desired shape on a mold, they are vacuum sealed and then cured under pressure, in a heated autoclave. A bond capable of withstanding extreme temperatures are produced.

  12. Determination of rare earth elements in environmental materials by inductively coupled plasma mass spectrometry

    SciTech Connect

    Panday, V.K.; Hoppstock, K.; Becker, J.S.; Dietze, H.J.

    1996-09-01

    Despite the fact that rare earth elements (REE) have found increasing use in modern technology only few data are available on their concentrations in biological and environmental samples. Inductively coupled plasma mass spectrometry (ICP-MS) has been employed to study the concentration of rare earth elements (REE) in various environmental materials (e.g., pine needles, mussel tissue, apple leaves) available from National Institute of Standards and Technology (NIST), the Bureau of European Communities (BCR), and the German Environmental Specimens Bank. After the decomposition of the environmental samples with HNO{sub 3}, the REE (present mostly in the ng/g-range) were separated from the matrix and simultaneously preconcentrated using liquid-liquid extraction with bis(2-ethyl hexyl)-ortho-phosphoric acid (HDEHP) in toluene as a selective reagent at pH = 2 and subsequent back extraction of the elements into the aqueous by 6M HNO{sub 3}. Recoveries of better 90% were obtained for almost all REE. A Perkin Elmer/Sciex ELAN 5000 ICP-MS and HR-ICP-MS ELEMENT from Finnigan MAT were used for quantitative analysis (by external calibration and ID-ICP-MS) of REE. The results of determination of REE concentrations agree well with the data available on some of these materials. Further supplement information on the contents of various REE in these materials.

  13. Coupling a reactive potential with a harmonic approximation for atomistic simulations of material failure

    NASA Astrophysics Data System (ADS)

    Tejada, Ignacio G.; Brochard, Laurent; Lelièvre, Tony; Stoltz, Gabriel; Legoll, Frédéric; Cancès, Eric

    2016-06-01

    Molecular dynamics (MD) simulations involving reactive potentials can be used to model material failure. The empirical potentials which are used in such simulations are able to adapt to the atomic environment, at the expense of a significantly higher computational cost than non-reactive potentials. However, during a simulation of failure, the reactive ability is needed only in some limited parts of the system, where bonds break or form and the atomic environment changes. Therefore, simpler non-reactive potentials can be used in the remainder of the system, provided that such potentials reproduce correctly the behavior of the reactive potentials in this region, and that seamless coupling is ensured at the interface between the reactive and non-reactive regions. In this article, we propose a methodology to combine a reactive potential with a non-reactive approximation thereof, made of a set of harmonic pair and angle interactions and whose parameters are adjusted to predict the same energy, geometry and Hessian in the ground state of the potential. We present a methodology to construct the non-reactive approximation of the reactive potential, and a way to couple these two potentials. We also propose a criterion for on-the-fly substitution of the reactive potential by its non-reactive approximation during a simulation. We illustrate the correctness of this hybrid technique for the case of MD simulation of failure in two-dimensional graphene originally modeled with REBO potential.

  14. Phosphorus speciation by coupled HPLC-ICPMS: low level determination of reduced phosphorus in natural materials

    NASA Astrophysics Data System (ADS)

    Atlas, Zachary; Pasek, Matthew; Sampson, Jacqueline

    2015-04-01

    Phosphorus is a geologically important minor element in the Earth's crust commonly found as relatively insoluble apatite. This constraint causes phosphorus to be a key limiting nutrient in biologic processes. Despite this, phosphorus plays a direct role in the formation of DNA, RNA and other cellular materials. Recent works suggest that since reduced phosphorus is considerably more soluble than oxidized phosphorus that it was integrally involved in the development of life on the early Earth and may continue to play a role in biologic productivity to this day. This work examines a new method for quantification and identification of reduced phosphorus as well as applications to the speciation of organo-phosphates separated by coupled HPLC - ICP-MS. We show that reduced phosphorus species (P1+, P3+ and P5+) are cleanly separated in the HPLC and coupled with the ICPMS reaction cell, using oxygen as a reaction gas to effectively convert elemental P to P-O. Analysis at M/Z= 47 producing lower background and flatter baseline chromatography than analyses performed at M/Z = 31. Results suggest very low detection limits (0.05 μM) for P species analyzed as P-O. Additionally we show that this technique has potential to speciate at least 5 other forms of phosphorus compounds. We verified the efficacy of method on numerous materials including leached Archean rocks, suburban retention pond waters, blood and urine samples and most samples show small but detectible levels of reduced phosphorus and or organo-phaospates. This finding in nearly all substances analyzed supports the assumption that the redox processing of phosphorus has played a significant role throughout the history of the Earth and it's presence in the present environment is nearly ubiquitous with the reduced oxidation state phosphorus compounds, phosphite and hypophosphite, potentially acting as significant constituents in the anaerobic environment.

  15. Effects of the methyltrimethoxysilane coupling agent on phenolic and miscanthus composites containing calcium sulfite scrubber material

    NASA Astrophysics Data System (ADS)

    Jones, Sean

    The purpose of this research is to test the effects of methyltrimethoxysilane coupling agent on composite material containing calcium sulfite obtained from the Southern Illinois Power Co-operative. This scrubber material and the miscanthus plant are of interest due to their use in coal burning power plants to reduce toxic emission. When calcium sulfate is passed through coal fire gas emissions it absorbs mercury and sulfur. In these composites it is used as filler to reduce cost. Miscanthus is a source of both cellulose reinforcement and some natural resin. This plant has low care requirements, little mineral content, useful energy return, and positive environmental effects. Under investigation is whether a post-cure procedure or a silane coupling agent will positively impact the composite. Hot pressing alone may not be enough to fully cure the phenolic. It is hoped that the silane will increase the strength characteristics of the composite by enhancing adhesion between the calcium sulfite and phenolic resin. Possible effects on the miscanthus by the silane will also be tested. Phenolic is being utilized because of its recycling and biodegradable properties along with cost effectiveness in mass production. Composite mechanical performance was measured through 3-point bending to measure flexural strength and strain at breakage. A dynamic mechanical analyzer (DMA) was used to find thermomechanical properties. The post-cure was found to be effective, particularly on the final composite containing silane. When methyltrimethoxysilane was added to the miscanthus prior to fabrication, it was found to reduce flexural strength and density. However the addition of methyltrimethoxysilane to the calcium sulfite altered thermo-mechanical properties to a state more like pure phenolic, with added flexibility and thermal stability.

  16. Predicate Adjective Usage in Standard Russian.

    ERIC Educational Resources Information Center

    Benson, Morton

    1959-01-01

    This paper describes predicate adjective usage in modern standard Russian using a corpus of written Russian derived from "Pravda" (neutral literary style) and "Krokodil" (conversational material). The short, long nominative, and instrumental forms are examined in relation to the type of adjective, copulative verb, sentence subject, and other…

  17. Coupling Solar Energy into Reactions: Materials Design for Surface Plasmon-Mediated Catalysis.

    PubMed

    Long, Ran; Li, Yu; Song, Li; Xiong, Yujie

    2015-08-26

    Enabled by surface plasmons, noble metal nanostructures can interact with and harvest incident light. As such, they may serve as unique media to generate heat, supply energetic electrons, and provide strong local electromagnetic fields for chemical reactions through different mechanisms. This solar-to-chemical pathway provides a new approach to solar energy utilization, alternative to conventional semiconductor-based photocatalysis. To provide readers with a clear picture of this newly recognized process, this review presents coupling solar energy into chemical reactions through plasmonic nanostructures. It starts with a brief introduction of surface plasmons in metallic nanostructures, followed by a demonstration of tuning plasmonic features by tailoring their physical parameters. Owing to their tunable plasmonic properties, metallic materials offer a platform to trigger and drive chemical reactions at the nanoscale, as systematically overviewed in this article. The design rules for plasmonic materials for catalytic applications are further outlined based on existing examples. At the end of this article, the challenges and opportunities for further development of plasmonic-mediated catalysis toward energy and environmental applications are discussed. PMID:26097101

  18. A Macroscopic Reaction: Direct Covalent Bond Formation between Materials Using a Suzuki-Miyaura Cross-Coupling Reaction

    NASA Astrophysics Data System (ADS)

    Sekine, Tomoko; Kakuta, Takahiro; Nakamura, Takashi; Kobayashi, Yuichiro; Takashima, Yoshinori; Harada, Akira

    2014-09-01

    Cross-coupling reactions are important to form C-C covalent bonds using metal catalysts. Although many different cross-coupling reactions have been developed and applied to synthesize complex molecules or polymers (macromolecules), if cross-coupling reactions are realized in the macroscopic real world, the scope of materials should be dramatically broadened. Here, Suzuki-Miyaura coupling reactions are realized between macroscopic objects. When acrylamide gel modified with an iodophenyl group (I-gel) reacts with a gel possessing a phenylboronic group (PB-gel) using a palladium catalyst, the gels bond to form a single object. This concept can also be adapted for bonding between soft and hard materials. I-gel or PB-gel selectively bonds to the glass substrates whose surfaces are modified with an electrophile or nucleophile, respectively.

  19. A Macroscopic Reaction: Direct Covalent Bond Formation between Materials Using a Suzuki-Miyaura Cross-Coupling Reaction

    PubMed Central

    Sekine, Tomoko; Kakuta, Takahiro; Nakamura, Takashi; Kobayashi, Yuichiro; Takashima, Yoshinori; Harada, Akira

    2014-01-01

    Cross-coupling reactions are important to form C–C covalent bonds using metal catalysts. Although many different cross-coupling reactions have been developed and applied to synthesize complex molecules or polymers (macromolecules), if cross-coupling reactions are realized in the macroscopic real world, the scope of materials should be dramatically broadened. Here, Suzuki-Miyaura coupling reactions are realized between macroscopic objects. When acrylamide gel modified with an iodophenyl group (I-gel) reacts with a gel possessing a phenylboronic group (PB-gel) using a palladium catalyst, the gels bond to form a single object. This concept can also be adapted for bonding between soft and hard materials. I-gel or PB-gel selectively bonds to the glass substrates whose surfaces are modified with an electrophile or nucleophile, respectively. PMID:25231557

  20. Laser ablation inductively coupled plasma optical emission spectrometry for analysis of pellets of plant materials

    NASA Astrophysics Data System (ADS)

    Gomes, Marcos S.; Schenk, Emily R.; Santos, Dário; Krug, Francisco José; Almirall, José R.

    An evaluation of laser ablation inductively coupled plasma optical emission spectroscopy (LAICP OES) for the direct analysis of pelleted plant material is reported. Ground leaves of orange citrus, soy and sugarcane were comminuted using a high-speed ball mill, pressed into pellets and sampled directly with laser ablation and analyzed by ICP OES. The limits of detection (LODs) for the method ranged from as low as 0.1 mg kg- 1 for Zn to as high as 94 mg kg- 1 for K but were generally below 6 mg kg- 1 for most of the elements of interest. A certified reference material consisting of a similar matrix (NIST SRM 1547 peach leaves) was used to check the accuracy of the calibration and the reported method resulted in an average bias of ~ 5% for all the elements of interest. The precision for the reported method ranged from as low as 4% relative standard deviation (RSD) for Mn to as high as 17% RSD for Zn but averaged ~ 6.5% RSD for all the elements (n = 10). The proposed method was tested for the determination of Ca, Mg, P, K, Fe, Mn, Zn and B, and the results were in good agreement with those obtained for the corresponding acid digests by ICP-OES, no differences being observed by applying a paired t-test at the 95% confidence level. The reported direct solid sampling method provides a fast alternative to acid digestion that results in similar and appropriate analytical figures of merit with regard to sensitivity, accuracy and precision for plant material analysis.

  1. Online CME usage patterns.

    PubMed

    Mazzoleni, M Cristina; Rognoni, Carla; Finozzi, Enrico; Giorgi, Ines; Pagani, Marco; Imbriani, Marcello

    2011-01-01

    The paper reports the findings of the analysis of a sample of 829 online Continuous Medical Education (CME) enrolments aimed at inspecting users' preferences and behaviours. The contents of the analyzed course are provided as online SCORM (Sharable Content Object Reference Model) resources together with the corresponding Pdf downloadable versions allowing different usage patterns (online only, Pdf only, online AND Pdf, mixed online OR Pdf). The results point out that there is not a specific preference for one of the four patterns and that most of the users access both navigable modules and Pdf documents. Demographic characteristics and initial knowledge level do not influence the choice of a specific usage pattern that probably depends on internal or context factors. From the point of view of knowledge acquisition, the four patterns are equivalent. As regards users' behaviour, the analysis has pointed out two issues: 1) the attitude to conclude the course in a short time and to reach good test scores, but not the excellence; 2) learning activity tracing data were not available for all the enrolments. Cues for discussion are proposed. PMID:21893749

  2. Exposure and materiality of the secondary room and its impact on the impulse response of coupled-volume concert halls

    NASA Astrophysics Data System (ADS)

    Ermann, Michael; Johnson, Marty

    2005-06-01

    How does sound decay when one room is partially exposed to another (acoustically coupled)? More specifically, this research aims to quantify how operational and design decisions impact sound fields in the design of concert halls with acoustical coupling. By adding a second room to a concert hall, and designing doors to control the sonic transparency between the two rooms, designers can create a new, coupled acoustic. Concert halls use coupling to achieve a variable, longer, and distinct reverberant quality for their musicians and listeners. For this study a coupled-volume shoebox concert hall is conceived with a fixed geometric volume, form, and primary-room sound absorption. Aperture size and secondary-room sound absorption levels are established as variables. Statistical analysis of sound decay in this simulated hall suggests a highly sensitive relationship between the double-sloped condition and (1) architectural composition, as defined by the aperture size exposing the chamber and (2) materiality, as defined by the sound absorptance in the coupled volume. The theoretical, mathematical predictions are compared with coupled-volume concert hall field measurements and guidelines are suggested for future designs of coupled-volume concert halls.

  3. Opportunistic in vitro spontaneous generation of bioactive material via longitudinal coupling electrostatic discharge during cell sorting

    SciTech Connect

    Durack, G.; Kelley, S.; Ragheb, K.; Lawler, G.; Robinson, J.P. )

    1993-01-01

    It has previously been reported by numerous, investigators and therefore generally accepted, that at sample flow rates greater than 2,000 cells per second a sorting purity of 100% cannot achieved for sorts lasting 2 hours or more. The authors have developed a theoretical model, based on Maxwell's electromagnetic equations and basic quantum mechanics as applied to a Newtonian frame of reference, which explains to their satisfaction this phenomenon. Basically, as charged droplets containing cells selected for sorting are accelerated through the varying density electromagnetic field produced by the sorting plates, there is a 0.1% probability that a high energy gamma particle will strike the ground plane of the flow cytometer. If this occurs while the instantaneous acceleration of the cell in the droplet is less than 9.74 m/s[sup 2] the alpha particles scattered tangentially from the ground plane can be longitudinally coupled to the volume immediately surrounding the cell encased by the droplet. The radius of curvature of the droplet is such that the resulting bio-radiation undergoes total internal reflection (TIR) which effectively produces a pseudo-bireactive Dirac function. A Hilbert transform of this function clearly indicates that all possible solutions that balance this function can only be obtained if there is additional bioactive material present within droplet radius. Subsequent testing has repeatedly shown that in fact most of what was erroneously thought to be contamination during sorting can be explained through application of this theory. Further investigation is expected to lead to classification of this bioactive material as an other life form.

  4. Soft x-ray shock loading and momentum coupling in meteorite and planetary materials.

    SciTech Connect

    Lawrence, R. Jeffery; Remo, John L.; Furnish, Michael David

    2010-12-01

    X-ray momentum coupling coefficients, C{sub M}, were determined by measuring stress waveforms in planetary materials subjected to impulsive radiation loading from the Sandia National Laboratories Z-machine. Results from the velocity interferometry (VISAR) diagnostic provided limited equation-of-state data as well. Targets were iron and stone meteorites, magnesium rich olivine (dunite) solid and powder ({approx}5--300 {mu}m), and Si, Al, and Fe calibration targets. All samples were {approx}1 mm thick and, except for Si, backed by LiF single-crystal windows. The x-ray spectrum included a combination of thermal radiation (blackbody 170--237 eV) and line emissions from the pinch material (Cu, Ni, Al, or stainless steel). Target fluences 0.4--1.7 kJ/cm{sup 2} at intensities 43--260 GW/cm{sup 2} produced front surface plasma pressures 2.6--12.4 GPa. Stress waves driven into the samples were attenuating due to the short ({approx}5 ns) duration of the drive pulse. Attenuating wave impulse is constant allowing accurate C{sub M} measurements provided mechanical impedance mismatch between samples and the window are known. Impedance-corrected C{sub M} determined from rear-surface motion was 1.9--3.1 x 10{sup -5} s/m for stony meteorites, 2.7 and 0.5 x 10{sup -5} s/m for solid and powdered dunite, 0.8--1.4 x 10{sup -5}.

  5. All-fiber-coupled laser-induced breakdown spectroscopy sensor for hazardous materials analysis

    NASA Astrophysics Data System (ADS)

    Bohling, Christian; Hohmann, Konrad; Scheel, Dirk; Bauer, Christoph; Schippers, Wolfgang; Burgmeier, Jörg; Willer, Ulrike; Holl, Gerhard; Schade, Wolfgang

    2007-12-01

    An all-fiber-coupled laser-induced breakdown spectroscopy (LIBS) sensor device is developed. A passively Q-switched Cr 4+Nd 3+:YAG microchip laser is amplified within an Yb fiber amplifier, thus generating high power laser pulses (pulse energy Ep = 0.8 mJ, wavelength λ = 1064 nm, repetition rate frep. = 5 kHz, pulse duration tp = 1.2 ns). A passive (LMA) optical fiber is spliced to the active fiber of an Yb fiber amplifier for direct guiding of high power laser pulses to the sensor tip. In front of the sensor a plasma is generated on the surface to be analyzed. The plasma emission is collected by a set of optical fibers also integrated into the sensor tip. The spectrally resolved LIBS spectra are processed by application of principal component analysis (PCA) and analyzed together with the time-resolved spectra with neural networks. Such procedure allows accurate analysis of samples by LIBS even for materials with similar atomic composition. The system has been tested successfully during field measurements at the German Armed Forces test facility at Oberjettenberg. The LIBS sensor is not restricted to anti-personnel mine detection but has also the potential to be suitable for analysis of bulk explosives and surface contaminations with explosives, e.g. for the detection of improvised explosive devices (IEDs).

  6. Pore-Scale Process Coupling and Effective Surface Reaction Rates in Heterogeneous Subsurface Materials

    SciTech Connect

    Liu, Chongxuan; Liu, Yuanyuan; Kerisit, Sebastien N.; Zachara, John M.

    2015-09-01

    This manuscript provides a review of pore-scale researches in literature including experimental and numerical approaches, and scale-dependent behavior of geochemical and biogeochemical reaction rates in heterogeneous porous media. A mathematical equation that can be used to predict the scale-dependent behavior of geochemical reaction rates in heterogeneous porous media has been derived. The derived effective rate expression explicitly links the effective reaction rate constant to the intrinsic rate constant, and to the pore-scale variations in reactant concentrations in porous media. Molecular simulations to calculate the intrinsic rate constants were provided. A few examples of pore-scale simulations were used to demonstrate the application of the equation to calculate effective rate constants in heterogeneous materials. The results indicate that the deviation of effective rate constant from the intrinsic rate in heterogeneous porous media is caused by the pore-scale distributions of reactants and their correlation, which are affected by the pore-scale coupling of reactions and transport.

  7. Spark ablation-inductively coupled plasma spectrometry for analysis of geologic materials

    USGS Publications Warehouse

    Golightly, D.W.; Montaser, A.; Smith, B.L.; Dorrzapf, A.F., Jr.

    1989-01-01

    Spark ablation-inductively coupled plasma (SA-ICP) spectrometry is applied to the measurement of hafnium-zirconium ratios in zircons and to the determination of cerium, cobalt, iron, lead, nickel and phosphorus in ferromanganese nodules. Six operating parameters used for the high-voltage spark and argon-ICP combination are established by sequential simplex optimization of both signal-to-background ratio and signal-to-noise ratio. The time-dependences of the atomic emission signals of analytes and matrix elements ablated from a finely pulverized sample embedded in a pressed disk of copper demonstrate selective sampling by the spark. Concentration ratios of hafnium to zirconium in zircons are measured with a precision of 4% (relative standard deviation, RSD). For ferromanganese nodules, spectral measurements based on intensity ratios of analyte line to the Mn(II) 257.610 nm line provide precisions of analysis in the range from 7 to 14% RSD. The accuracy of analysis depends on use of standard additions of the reference material USGS Nod P-1, and an independent measurement of the Mn concentration. ?? 1989.

  8. Air-coupled detection of nonlinear Rayleigh surface waves to assess material nonlinearity.

    PubMed

    Thiele, Sebastian; Kim, Jin-Yeon; Qu, Jianmin; Jacobs, Laurence J

    2014-08-01

    This research presents a new technique for nonlinear Rayleigh surface wave measurements that uses a non-contact, air-coupled ultrasonic transducer; this receiver is less dependent on surface conditions than laser-based detection, and is much more accurate and efficient than detection with a contact wedge transducer. A viable experimental setup is presented that enables the robust, non-contact measurement of nonlinear Rayleigh surface waves over a range of propagation distances. The relative nonlinearity parameter is obtained as the slope of the normalized second harmonic amplitudes plotted versus propagation distance. This experimental setup is then used to assess the relative nonlinearity parameters of two aluminum alloy specimens (Al 2024-T351 and Al 7075-T651). These results demonstrate the effectiveness of the proposed technique - the average standard deviation of the normalized second harmonic amplitudes, measured at locations along the propagation path, is below 2%. Experimental validation is provided by a comparison of the ratio of the measured nonlinearity parameters of these specimens with ratios from the absolute nonlinearity parameters for the same materials measured by capacitive detection of nonlinear longitudinal waves. PMID:24836962

  9. TAP usage in SIMBAD

    NASA Astrophysics Data System (ADS)

    Anaïs, O.; Gregory, M.; Marc, W.

    2015-09-01

    TAP (Table Access Protocol promoted by IVOA) is available on SIMBAD web site since July 2012. We will have a look of all kinds of uses and try to figure out how people use it in SIMBAD. Thanks to ADQL (Astronomical Data Query Language), everyone can write their own query using criteria on all data available in the database. In the SIMBAD database, more than 30 tables are available. It can be rather difficult to write a complex query. We will see how many joins between tables are used, and how many fields are used in the queries. The SIMBAD usage is going to change thanks to this new feature, a new way to search in the database.

  10. STM probe on the surface electronic states of spin-orbit coupled materials

    NASA Astrophysics Data System (ADS)

    Zhou, Wenwen

    Spin-orbit coupling (SOC) is the interaction of an electron's intrinsic angular momentum (spin) with its orbital momentum. The strength of this interaction is proportional to Z4 where Z is the atomic number, so generally it is stronger in atoms with higher atomic number, such as bismuth (Z=83) and iridium (Z=77). In materials composed of such heavy elements, the prominent SOC can be sufficient to modify the band structure of the system and lead to distinct phase of matter. In recent years, SOC has been demonstrated to play a critical role in determining the unusual properties of a variety of compounds. SOC associated materials with exotic electronic states have also provided a fertile platform for studying emergent phenomena as well as new physics. As a consequence, the research on these interesting materials with any insight into understanding the microscopic origin of their unique properties and complex phases is of great importance. In this context, we implement scanning tunneling microscopy (STM) and spectroscopy (STS) to explore the surface states (SS) of the two major categories of SOC involved materials, Bi-based topological insulators (TI) and Ir-based transition metal oxides (TMO). As a powerful tool in surface science which has achieved great success in wide variety of material fields, STM/STS is ideal to study the local density of states of the subject material with nanometer length scales and is able to offer detailed information about the surface electronic structure. In the first part of this thesis, we report on the electronic band structures of three-dimensional TIs Bi2Te3 and Bi2Se 3. Topological insulators are distinct quantum states of matter that have been intensely studied nowadays. Although they behave like ordinary insulators in showing fully gapped bulk bands, they host a topologically protected surface state consisting of two-dimensional massless Dirac fermions which exhibits metallic behavior. Indeed, this unique gapless surface state is a

  11. Optimality criteria-based topology optimization of a bi-material model for acoustic-structural coupled systems

    NASA Astrophysics Data System (ADS)

    Shang, Linyuan; Zhao, Guozhong

    2016-06-01

    This article investigates topology optimization of a bi-material model for acoustic-structural coupled systems. The design variables are volume fractions of inclusion material in a bi-material model constructed by the microstructure-based design domain method (MDDM). The design objective is the minimization of sound pressure level (SPL) in an interior acoustic medium. Sensitivities of SPL with respect to topological design variables are derived concretely by the adjoint method. A relaxed form of optimality criteria (OC) is developed for solving the acoustic-structural coupled optimization problem to find the optimum bi-material distribution. Based on OC and the adjoint method, a topology optimization method to deal with large calculations in acoustic-structural coupled problems is proposed. Numerical examples are given to illustrate the applications of topology optimization for a bi-material plate under a low single-frequency excitation and an aerospace structure under a low frequency-band excitation, and to prove the efficiency of the adjoint method and the relaxed form of OC.

  12. English Usage in Hong Kong.

    ERIC Educational Resources Information Center

    Bunton, David, Ed.; Green, Christopher F., Ed.

    1991-01-01

    Articles contained in this special issue on language usage in Hong Kong, particularly in the context of elementary and secondary education, include: "A Comparison of English Errors Made by Hong Kong Students and Those Made by Non-Native Learners of English Internationally" (David Bunton); "Errors in Guides to English Usage for Hong Kong Students"…

  13. Photograph Usage in History Education

    ERIC Educational Resources Information Center

    Akbaba, Bulent

    2009-01-01

    In this study, the effect of photograph usage in history education to the students' achievement was tried to be identified. In the study which was done with a pre-test post-test control group design, a frame was tried to be established between the experimental group and the analytical usage of the photograph, the control group's courses were done…

  14. Internal neutronics-temperature coupling in Serpent 2 - Reactivity differences resulting from choice of material property correlations

    SciTech Connect

    Valtavirta, V.

    2013-07-01

    This paper describes the unique way of simultaneously solving the power and temperature distributions of a nuclear system with the Monte Carlo neutron transport code Serpent 2. The coupled solution is achieved through the implementation of an internal temperature solver and material property correlations in the code. The program structure is reviewed concerning the temperature solver and the internal correlations as well as the internal coupling between these two and the neutron transport part. To estimate the reactivity differences resulting from correlation choices a simple pin-cell case has been calculated. It is established, that some correlation choices may result in difference in reactivity of approximately 100 pcm. (authors)

  15. Electron-Vibration Coupling in Molecular Materials: Assignment of Vibronic Modes from Photoelectron Momentum Mapping

    NASA Astrophysics Data System (ADS)

    Graus, M.; Grimm, M.; Metzger, C.; Dauth, M.; Tusche, C.; Kirschner, J.; Kümmel, S.; Schöll, A.; Reinert, F.

    2016-04-01

    Electron-phonon coupling is one of the most fundamental effects in condensed matter physics. We here demonstrate that photoelectron momentum mapping can reveal and visualize the coupling between specific vibrational modes and electronic excitations. When imaging molecular orbitals with high energy resolution, the intensity patterns of photoelectrons of the vibronic sidebands of molecular states show characteristic changes due to the distortion of the molecular frame in the vibronically excited state. By comparison to simulations, an assignment of specific vibronic modes is possible, thus providing unique information on the coupling between electronic and vibronic excitation.

  16. Electron-Vibration Coupling in Molecular Materials: Assignment of Vibronic Modes from Photoelectron Momentum Mapping.

    PubMed

    Graus, M; Grimm, M; Metzger, C; Dauth, M; Tusche, C; Kirschner, J; Kümmel, S; Schöll, A; Reinert, F

    2016-04-01

    Electron-phonon coupling is one of the most fundamental effects in condensed matter physics. We here demonstrate that photoelectron momentum mapping can reveal and visualize the coupling between specific vibrational modes and electronic excitations. When imaging molecular orbitals with high energy resolution, the intensity patterns of photoelectrons of the vibronic sidebands of molecular states show characteristic changes due to the distortion of the molecular frame in the vibronically excited state. By comparison to simulations, an assignment of specific vibronic modes is possible, thus providing unique information on the coupling between electronic and vibronic excitation. PMID:27104726

  17. Hybrid optical materials of plasmon-coupled CdSe/ZnS coreshells for photonic applications

    PubMed Central

    Seo, Jaetae; Fudala, Rafal; Kim, Wan-Joong; Rich, Ryan; Tabibi, Bagher; Cho, Hyoyeong; Gryczynski, Zygmunt; Gryczynski, Ignacy; Yu, William

    2013-01-01

    A hybrid optical nanostructure of plasmon-coupled SQDs was developed for photonic applications. The coupling distances between the mono-layers of Au nanoparticles with a surface concentration of ~9.18 × 10−4 nm−2 and CdSe/ZnS SQDs with that of ~3.7 × 10−3 nm−2 were controlled by PMMA plasma etching. Time-resolved spectroscopy of plasmon-coupled SQDs revealed a strong shortening of the longest lifetime and ~9-fold PL enhancement. Polarization-resolved PL spectroscopy displayed linear polarization and depolarization at near- and far-field plasmon-coupling, respectively. The physical origin of PL enhancement could be attributable to both the large local field enhancement and the fast resonant energy transfer. PMID:23457661

  18. A correlation of air-coupled ultrasonic and thermal diffusivity data for CFCC materials

    SciTech Connect

    Pillai, T.A.K.; Easler, T.E.; Szweda, A.

    1997-01-01

    An air-coupled (non contact) through-transmission ultrasonic investigation has been conducted on 2D multiple ply Nicalon{trademark} SiC fiber/SiNC CFCC panels as a function of number of processing cycles. Corresponding thermal diffusivity imaging was also conducted. The results of the air-coupled ultrasonic investigation correlated with thermal property variations determined via infrared methods. Areas of delaminations were detected and effects of processing cycles were also detected.

  19. Simple model for coupled magnetic and quadrupolar instabilities in uranium heavy-fermion materials

    SciTech Connect

    Libero, V.L. ); Cox, D.L. )

    1993-08-01

    We present a mean-field calculation of the phase diagram of a simple model of localized moments, in the hexagonal uranium heavy-fermion compounds. The model considers a non-Kramers quadrupolar doublet ground state magnetically coupled with a singlet excited state, favoring in-plane van Vleck magnetism, as has been conjectured for UPt[sub 3]. The Hamiltonian that defines the model is Heisenberg-like in both magnetic and quadrupolar moments. No Kondo-effect physics is included in the calculations. Among our main results are (i) for zero intersite quadrupolar coupling, the magnetic order is achieved by a first-order transition above a critical intersite magnetic coupling value, which becomes second order at higher coupling strengths (ii) for finite intersite quadrupolar coupling, at temperatures below a second-order quadrupolar ordering transition, the minimal magnetic coupling value is increased, but (a) the magnetic ordering temperature is enhanced above this value, and (b) the ordering of first- and second-order transitions in the phase diagram is reversed. By considering the general structure of the Ginsburg-Landau free energy, we argue that the Kondo effect will not modify the shape of the phase diagram, but will modify the quantitative values at which transitions occur.

  20. Radio frequency coupling apparatus and method for measuring minority carrier lifetimes in semiconductor materials

    DOEpatents

    Johnston, Steven W.; Ahrenkiel, Richard K.

    2002-01-01

    An apparatus for measuring the minority carrier lifetime of a semiconductor sample using radio-frequency coupling. The measuring apparatus includes an antenna that is positioned a coupling distance from a semiconductor sample which is exposed to light pulses from a laser during sampling operations. A signal generator is included to generate high frequency, such as 900 MHz or higher, sinusoidal waveform signals that are split into a reference signal and a sample signal. The sample signal is transmitted into a sample branch circuit where it passes through a tuning capacitor and a coaxial cable prior to reaching the antenna. The antenna is radio-frequency coupled with the adjacent sample and transmits the sample signal, or electromagnetic radiation corresponding to the sample signal, to the sample and receives reflected power or a sample-coupled-photoconductivity signal back. To lower impedance and speed system response, the impedance is controlled by limiting impedance in the coaxial cable and the antenna reactance. In one embodiment, the antenna is a waveguide/aperture hybrid antenna having a central transmission line and an adjacent ground flange. The sample-coupled-photoconductivity signal is then transmitted to a mixer which also receives the reference signal. To enhance the sensitivity of the measuring apparatus, the mixer is operated to phase match the reference signal and the sample-coupled-photoconductivity signal.

  1. A thermo-mechanically coupled theory for fluid permeation in elastomeric materials: Application to thermally responsive gels

    NASA Astrophysics Data System (ADS)

    Chester, Shawn A.; Anand, Lallit

    2011-10-01

    An elastomeric gel is a cross-linked polymer network swollen with a solvent, and certain gels can undergo large reversible volume changes as they are cycled about a critical temperature. We have developed a continuum-level theory to describe the coupled mechanical deformation, fluid permeation, and heat transfer of such thermally responsive gels. In discussing special constitutive equations we limit our attention to isotropic materials, and consider a model based on a Flory-Huggins model for the free energy change due to mixing of the fluid with the polymer network, coupled with a non-Gaussian statistical-mechanical model for the change in configurational entropy—a model which accounts for the limited extensibility of polymer chains. We have numerically implemented our theory in a finite element program. We show that our theory is capable of simulating swelling, squeezing of fluid by applied mechanical forces, and thermally responsive swelling/de-swelling of such materials.

  2. Vacuum-induced phonon transfer between two solid dielectric materials: Illustrating the case of Casimir force coupling

    NASA Astrophysics Data System (ADS)

    Ezzahri, Younès; Joulain, Karl

    2014-09-01

    The natural transition from the radiative regime to the conductive regime of heat transfer between two identical isotropic nonmagnetic dielectric solid materials is questioned by investigating the possibility of induced phonon transfer in vacuum. We describe the process in a general way assuming a certain phonon coupling mechanism between the two identical solids, then we particularly illustrate the case of coupling through the Casimir force. We analyze how this mechanism of heat transfer compares and competes with the near field thermal radiation using a local model of the dielectric function. We show that the former mechanism can be very effective and even surpass the latter mechanism depending on the nature of the solid dielectric materials, the distance gap between them, as well as the operating temperature regime.

  3. Modeling of time-resolved coupled radiative and conductive heat transfer in multilayer semitransparent materials up to very high temperatures

    NASA Astrophysics Data System (ADS)

    Niezgoda, M.; Rochais, D.; Enguehard, F.; Echegut, P.; Rousseau, B.

    2011-11-01

    This paper presents an original modeling approach that enables the calculation of the temperature field within multilayer materials submitted to the flash method. The model takes into account the time-resolved coupled conducto-radiative heat transfer and the temperature of experiments. The compound can be subdivided into as many layers as desired, and their thicknesses and relevant physical properties can be chosen arbitrarily. Unconventional experimental thermograms can be reproduced faithfully by the calculations. This model, thus, makes it possible to correctly estimate the effective thermal diffusivity of semitransparent materials, thereby providing a deeper insight into the analysis of the physical phenomena involved.

  4. Marijuana Usage and Hypnotic Susceptibility

    ERIC Educational Resources Information Center

    Franzini, Louis R.; McDonald, Roy D.

    1973-01-01

    Anonymous self-reported drug usage data and hypnotic susceptibility scores were obtained from 282 college students. Frequent marijuana users (more than 10 times) showed greater susceptibility to hypnosis than nonusers. (Author)

  5. Improving the sensitivity of J coupling measurements in solids with application to disordered materials

    NASA Astrophysics Data System (ADS)

    Guerry, Paul; Brown, Steven P.; Smith, Mark E.

    2016-05-01

    It has been shown previously that for magic angle spinning (MAS) solid state NMR the refocused INADEQUATE spin-echo (REINE) experiment can usefully quantify scalar (J) couplings in disordered solids. This paper focuses on the two z filter components in the original REINE pulse sequence, and investigates by means of a product operator analysis and fits to density matrix simulations the effects that their removal has on the sensitivity of the experiment and on the accuracy of the extracted J couplings. The first z filter proves unnecessary in all the cases investigated here and removing it increases the sensitivity of the experiment by a factor ˜1.1-2.0. Furthermore, for systems with broad isotropic chemical shift distributions (namely whose full widths at half maximum are greater than 30 times the mean J coupling strength), the second z filter can also be removed, thus allowing whole-echo acquisition and providing an additional √2 gain in sensitivity. Considering both random and systematic errors in the values obtained, J couplings determined by fitting the intensity modulations of REINE experiments carry an uncertainty of 0.2-1.0 Hz (˜1-10 %).

  6. Coupled hydro-mechanical effects in a poro-hyperelastic material

    NASA Astrophysics Data System (ADS)

    Selvadurai, A. P. S.; Suvorov, A. P.

    2016-06-01

    Fluid-saturated materials are encountered in several areas of engineering and biological applications. Geologic media saturated with water, oil and gas and biological materials such as bone saturated with synovial fluid, soft tissues containing blood and plasma and synthetic materials impregnated with energy absorbing fluids are some examples. In many instances such materials can be examined quite successfully by appeal to classical theories of poroelasticity where the skeletal deformations can be modelled as linear elastic. In the case of soft biological tissues and even highly compressible organic geological materials, the porous skeleton can experience large strains and, unlike rubberlike materials, the fluid plays an important role in maintaining the large strain capability of the material. In some instances, the removal of the fluid can render the geological or biological material void of any hyperelastic effects. While the fluid component can be present at various scales and forms, a useful first approximation would be to treat the material as hyperelastic where the fabric can experience large strains consistent with a hyperelastic material and an independent scalar pressure describes the pore fluid response. The flow of fluid within the porous skeleton is defined by Darcy's law for an isotropic material, which is formulated in terms of the relative velocity between the pore fluid and the porous skeleton. It is assumed that the form of Darcy's law remains unchanged during the large strain behaviour. This approach basically extends Biot's theory of classical poroelasticity to include finite deformations. The developments are used to examine the poro-hyperelastic behaviour of certain one-dimensional problems.

  7. Bringing Far-Field Subdiffraction Optical Imaging to Electronically Coupled Optoelectronic Molecular Materials Using Their Endogenous Chromophores.

    PubMed

    Penwell, Samuel B; Ginsberg, Lucas D S; Ginsberg, Naomi S

    2015-07-16

    We demonstrate that subdiffraction resolution can be achieved in fluorescence imaging of functional materials with densely packed, endogenous, electronically coupled chromophores by modifying stimulated emission depletion (STED) microscopy. This class of chromophores is not generally compatible with STED imaging due to strong two-photon absorption cross sections. Yet, we achieve 90 nm resolution and high contrast in images of clusters of conjugated polymer polyphenylenevinylene-derivative nanoparticles by modulating the excitation intensity in the material. This newfound capability has the potential to significantly broaden the range of fluorophores that can be employed in super-resolution fluorescence imaging. Moreover, solution-processed optoelectronics and photosynthetic or other naturally luminescent biomaterials exhibit complex energy and charge transport characteristics and luminescence variations in response to nanoscale heterogeneity in their complex, physical structures. Our discovery will furthermore transform the current understanding of these materials' structure-function relationships that have until now made them notoriously challenging to characterize on their native, subdiffraction scales. PMID:26266861

  8. Determination of rare earth elements in geological materials by inductively coupled argon plasma/atomic emission spectrometry

    USGS Publications Warehouse

    Crock, J.G.; Lichte, F.E.

    1982-01-01

    Inductively coupled argon plasma/optical emission spectrometery (ICAP/OES) is useful as a simultaneous, multielement analytical technique for the determination of trace elements in geological materials. A method for the determination of trace-level rare earth elements (REE) in geological materials using an ICAP 63-channel emission spectrometer is described. Separation and preconcentration of the REE and yttrium from a sample digest are achieved by a nitric acid gradient cation exchange and hydrochloric acid anion exchange. Precision of 1-4% relative standard deviation and comparable accuracy are demonstrated by the triplicate analysis of three splits of BCR-1 and BHVO-1. Analyses of other geological materials including coals, soils, and rocks show comparable precision and accuracy.

  9. Spin-to-charge conversion using Rashba coupling at the interface between non-magnetic materials.

    PubMed

    Sánchez, J C Rojas; Vila, L; Desfonds, G; Gambarelli, S; Attané, J P; De Teresa, J M; Magén, C; Fert, A

    2013-01-01

    The Rashba effect is an interaction between the spin and the momentum of electrons induced by the spin-orbit coupling (SOC) in surface or interface states. Its potential for conversion between charge and spin currents has been theoretically predicted but never clearly demonstrated for surfaces or interfaces of metals. Here we present experiments evidencing a large spin-charge conversion by the Bi/Ag Rashba interface. We use spin pumping to inject a spin current from a NiFe layer into a Bi/Ag bilayer and we detect the resulting charge current. As the charge signal is much smaller (negligible) with only Bi (only Ag), the spin-to-charge conversion can be unambiguously ascribed to the Rashba coupling at the Bi/Ag interface. This result demonstrates that the Rashba effect at interfaces can be used for efficient charge-spin conversion in spintronics. PMID:24343336

  10. Self-aligned optical couplings by self-organized waveguides toward luminescent targets in organic/inorganic hybrid materials.

    PubMed

    Yoshimura, Tetsuzo; Iida, Makoto; Nawata, Hideyuki

    2014-06-15

    Self-organization of optical waveguides is observed between two opposed optical fibers placed in a photosensitive organic/inorganic hybrid material, Sunconnect. A luminescent target containing coumarin 481 was deposited onto the edge of one of the two fibers at the core. When a 448-nm write beam was introduced from the other fiber, the write beam and the luminescence from the photoexcited target increased the refractive index of Sunconnect to induce self-focusing. Traces of waveguides were seen to grow from the cores of both fibers and merged into a single self-aligned optical coupling between the fibers. This optical solder functionality enabled increases in both coupling efficiency and tolerance to lateral misalignment of the fibers. PMID:24978520

  11. On the material and the tribology of alumina-alumina couplings for hip joint prostheses.

    PubMed

    Walter, A

    1992-09-01

    The yearly sphericity deviation ranged from 0.03 mu to 3.7 mm in 48 retrieved implants with alumina--alumina bearing balls and cups. Excessive amounts of wear are predominantly design dependent or caused by malalignment. But the abrasion phenomena occurring in the cup centers and in the corresponding ball areas are related to unfavorable function zones. The influence of the lubricating gap geometry as studied in laboratory tests shows the form of sphericity deviations to be of decisive importance for wear and friction, if extended over small angles. Then, the contact stresses attributable to the actual effective curvatures of the bearing exceed the resistance to abrasion of the material under boundary lubrication conditions. There are remarkable differences between the early and actual material quality. Based on the state of knowledge of material aspects of wear criteria for the optimization of material and design, promising tolerable wear rates may be achieved. PMID:1516324

  12. Materials considerations for the coupling of thermochemical hydrogen cycles to tandem mirror reactors

    SciTech Connect

    Krikorian, O.H.

    1980-10-10

    Candidate materials are discussed and initial choices made for the critical elements in a liquid Li-Na Cauldron Tandem Mirror blanket and the General Atomic Sulfur-Iodine Cycle for thermochemical hydrogen production. V and Ti alloys provide low neutron activation, good radiation damage resistance, and good chemical compatibility for the Cauldron design. Aluminide coated In-800H and siliconized SiC are materials choices for heat exchanger components in the thermochemical cycle interface.

  13. Manipulation of surface plasmon polariton propagation on isotropic and anisotropic two-dimensional materials coupled to boron nitride heterostructures

    NASA Astrophysics Data System (ADS)

    Inampudi, Sandeep; Nazari, Mina; Forouzmand, Ali; Mosallaei, Hossein

    2016-01-01

    We present a comprehensive analysis of surface plasmon polariton dispersion characteristics associated with isotropic and anisotropic two-dimensional atomically thin layered materials (2D sheets) coupled to h-BN heterostructures. A scattering matrix based approach is presented to compute the electromagnetic fields and related dispersion characteristics of stacked layered systems composed of anisotropic 2D sheets and uniaxial bulk materials. We analyze specifically the surface plasmon polariton (SPP) dispersion characteristics in case of isolated and coupled two-dimensional layers with isotropic and anisotropic conductivities. An analysis based on residue theorem is utilized to identify optimum optical parameters (surface conductivity) and geometrical parameters (separation between layers) to maximize the SPP field at a given position. The effect of type and degree of anisotropy on the shapes of iso-frequency curves and propagation characteristics is discussed in detail. The analysis presented in this paper gives an insight to identify optimum setup to enhance the SPP field at a given position and in a given direction on the surface of two-dimensional materials.

  14. An analytical and explicit multi-field coupled nonlinear constitutive model for Terfenol-D giant magnetostrictive material

    NASA Astrophysics Data System (ADS)

    Zhou, Hao-Miao; Li, Meng-Han; Li, Xiao-Hong; Zhang, Da-Guang

    2016-08-01

    For a giant magnetostrictive rod under the action of multiple physical loads, such as an external magnetic field, temperature and axial pre-stress, this paper proposes a general one-dimensional nonlinear magneto-thermo-mechanical coupled constitutive model. This model is based on the Taylor expansion of the elastic Gibbs free energy of giant magnetostrictive material and thermodynamic relations from the perspective of macro continuum mechanics. Predictions made using this model are in good agreement with experimental data for magnetization and the magnetostrictive strain curve under the collective effect of pre-stress and temperature. Additionally, the model overcomes the drawback of the existing magneto-thermo-mechanical constitutive model that cannot accurately predict the magnetization and magnetostrictive strain curve for different temperatures and pre-stresses. Furthermore, the constitutive model does not contain an implicit function and is compact, and can thus be applied in both situations of tensile and compressive stress and to both positive and negative magnetostrictive materials, and it is thus appropriate for engineering applications. Comprehensive analysis shows that the model fully describes the nonlinear coupling properties of a magnetic field, magnetostrictive strain and elasticity of a magnetostrictive material subjected to stress, a magnetic field and heat.

  15. Coal ash usage in environmental restoration at the Hanford Site

    SciTech Connect

    Scanlon, P.L.; Sonnichsen, J.C.; Phillips, S.J.

    1995-09-01

    This paper discusses the use of coal ash from Hanford Nuclear Reservation steam plants as codisposal waste rock, landfill, or tank stabilization material; usage as a fuel source for energy recovery, as pipe or foundation backfill, or as an ornamental brick additive; and as aquarium rock, jewelry, or oyster bed stabilization material. Reducing the amount of waste produced is also discussed.

  16. Clio's Assistants: A Tool Suite for Exploring Student Web Usage.

    ERIC Educational Resources Information Center

    Fuller, Greg; Simonson, Joe; Tiwari, Ananta; Rebelsky, Samuel A.

    Since the inception of the World Wide Web, faculty members have been developing online course materials. However, there is little careful analysis of how students use these Webs. In particular, do more successful and less successful students use course webs and associated materials differently? Are usage patterns similar to those of printed…

  17. Deposition Of Materials Using A Simple Planar Coil Radio Frequency Inductively Coupled Plasma System

    SciTech Connect

    Ng, K. H.; Wong, C. S.; Yap, S. L.; Gan, S. N.

    2009-07-07

    A planar coil RF inductively coupled plasma (PC-RFICP) systems is set up for the purpose of thin film deposition. The system is powered by a 13.56 MHz, 550 W, 50 OMEGA RF generator. The RF power is transferred to the plasma via a planar induction coil. The impedance matching unit consists of an air core step-down transformer and a tunable vacuum capacitor. This system is used for the plasma enhanced chemical vapor deposition (PECVD) of diamond-like carbon (DLC) film on silicon substrate, and hydrogenated amorphous carbon (a-C:H) film.

  18. Plasma-driven Z-pinch X-ray loading and momentum coupling in meteorite and planetary materials

    NASA Astrophysics Data System (ADS)

    Remo, John L.; Furnish, Michael D.; Lawrence, R. Jeffery; Lawrence

    2013-04-01

    X-ray momentum coupling coefficients, C M, were determined by measuring stress waveforms in planetary materials subjected to impulsive radiation loading from the Sandia National Laboratories Z-machine. Velocity interferometry (VISAR) diagnostics provided equation-of-state data. Targets were iron and stone meteorites, magnesium-rich olivine (dunite) solid and powder (~5-300 μm), and Si, Al, and Fe calibration targets. Samples were ~1-mm thick and, except for Si, backed by LiF single-crystal windows. X-ray spectra combined thermal radiation (blackbody 170-237 eV) and line emissions from pinch materials (Cu, Ni, Al, or stainless steel). Target fluences of 0.4-1.7 kJ/cm2 at intensities of 43-260GW/cm2 produced plasma pressures of 2.6-12.4 GPa. The short (~5 ns) drive pulses gave rise to attenuating stress waves in the samples. The attenuating wave impulse is constant, allowing accurate C M measurements from rear-surface motion. C M was 1.9 - 3.1 × 10-5 s/m for stony meteorites, 2.7 and 0.5 × 10-5 s/m for solid and powdered dunite, 0.8 - 1.4 × 10-5 s/m for iron meteorites, and 0.3, 1.8, and 2.7 × 10-5 s/m respectively for Si, Fe, and Al calibration targets. Results are consistent with geometric scaling from recent laser hohlraum measurements. CTH hydrocode modeling of X-ray coupling to porous silica corroborated experimental measurements and supported extrapolations to other materials. CTH-modeled C M for porous materials was low and consistent with experimental results. Analytic modeling (BBAY) of X-ray radiation-induced momentum coupling to selected materials was also performed, often producing higher C M values than experimental results. Reasons for the higher values include neglect of solid ejecta mechanisms, turbulent mixing of heterogeneous phases, variances in heats of melt/vaporization, sample inhomogeneities, wave interactions at the sample/window boundary, and finite sample/window sizes. The measurements validate application of C M to (inhomogeneous

  19. A Perspective on Coupled Multiscale Simulation and Validation in Nuclear Materials

    SciTech Connect

    M. P. Short; D. Gaston; C. R. Stanek; S. Yip

    2014-01-01

    The field of nuclear materials encompasses numerous opportunities to address and ultimately solve longstanding industrial problems by improving the fundamental understanding of materials through the integration of experiments with multiscale modeling and high-performance simulation. A particularly noteworthy example is an ongoing study of axial power distortions in a nuclear reactor induced by corrosion deposits, known as CRUD (Chalk River unidentified deposits). We describe how progress is being made toward achieving scientific advances and technological solutions on two fronts. Specifically, the study of thermal conductivity of CRUD phases has augmented missing data as well as revealed new mechanisms. Additionally, the development of a multiscale simulation framework shows potential for the validation of a new capability to predict the power distribution of a reactor, in effect direct evidence of technological impact. The material- and system-level challenges identified in the study of CRUD are similar to other well-known vexing problems in nuclear materials, such as irradiation accelerated corrosion, stress corrosion cracking, and void swelling; they all involve connecting materials science fundamentals at the atomistic- and mesoscales to technology challenges at the macroscale.

  20. Signature of Strong Spin-Orbital Coupling in the Large Nonsaturating Magnetoresistance Material WTe2.

    PubMed

    Jiang, J; Tang, F; Pan, X C; Liu, H M; Niu, X H; Wang, Y X; Xu, D F; Yang, H F; Xie, B P; Song, F Q; Dudin, P; Kim, T K; Hoesch, M; Das, P Kumar; Vobornik, I; Wan, X G; Feng, D L

    2015-10-16

    We report the detailed electronic structure of WTe2 by high resolution angle-resolved photoemission spectroscopy. We resolved a rather complicated Fermi surface of WTe2. Specifically, there are in total nine Fermi pockets, including one hole pocket at the Brillouin zone center Γ, and two hole pockets and two electron pockets on each side of Γ along the Γ-X direction. Remarkably, we have observed circular dichroism in our photoemission spectra, which suggests that the orbital angular momentum exhibits a rich texture at various sections of the Fermi surface. This is further confirmed by our density-functional-theory calculations, where the spin texture is qualitatively reproduced as the conjugate consequence of spin-orbital coupling. Since the spin texture would forbid backscatterings that are directly involved in the resistivity, our data suggest that the spin-orbit coupling and the related spin and orbital angular momentum textures may play an important role in the anomalously large magnetoresistance of WTe2. Furthermore, the large differences among spin textures calculated for magnetic fields along the in-plane and out-of-plane directions also provide a natural explanation of the large field-direction dependence on the magnetoresistance. PMID:26550888

  1. Signature of Strong Spin-Orbital Coupling in the Large Nonsaturating Magnetoresistance Material WTe2

    NASA Astrophysics Data System (ADS)

    Jiang, J.; Tang, F.; Pan, X. C.; Liu, H. M.; Niu, X. H.; Wang, Y. X.; Xu, D. F.; Yang, H. F.; Xie, B. P.; Song, F. Q.; Dudin, P.; Kim, T. K.; Hoesch, M.; Das, P. Kumar; Vobornik, I.; Wan, X. G.; Feng, D. L.

    2015-10-01

    We report the detailed electronic structure of WTe2 by high resolution angle-resolved photoemission spectroscopy. We resolved a rather complicated Fermi surface of WTe2. Specifically, there are in total nine Fermi pockets, including one hole pocket at the Brillouin zone center Γ , and two hole pockets and two electron pockets on each side of Γ along the Γ -X direction. Remarkably, we have observed circular dichroism in our photoemission spectra, which suggests that the orbital angular momentum exhibits a rich texture at various sections of the Fermi surface. This is further confirmed by our density-functional-theory calculations, where the spin texture is qualitatively reproduced as the conjugate consequence of spin-orbital coupling. Since the spin texture would forbid backscatterings that are directly involved in the resistivity, our data suggest that the spin-orbit coupling and the related spin and orbital angular momentum textures may play an important role in the anomalously large magnetoresistance of WTe2. Furthermore, the large differences among spin textures calculated for magnetic fields along the in-plane and out-of-plane directions also provide a natural explanation of the large field-direction dependence on the magnetoresistance.

  2. A Novel Trihybrid Material Based on Renewables: An Efficient Recyclable Heterogeneous Catalyst for C-C Coupling and Reduction Reactions.

    PubMed

    Majumdar, Rakhi; Tantayanon, Supawan; Gopal Bag, Braja

    2016-09-01

    The generation of organic-inorganic hybrid materials from renewable resources and their utilization in basic and applied areas has been at the forefront of research in recent years for sustainable development. Herein, a novel organic-inorganic trihybrid material was synthesized by in situ generation of palladium nanoparticles (PdNPs) in a hybrid gel matrix based on renewable chemicals. Constituents of the hybrid gel included a pentacyclic triterpenoid arjunolic acid extractable from Terminalia arjuna and the leaf extract of Chrysophyllum cainito rich in flavonoids. We took advantage of the presence of flavonoid molecules in this hybrid gel to generate an advanced trihybrid gel through in situ reduction of doped Pd(II) salts to stable PdNPs. The xerogel of this trihybrid material was used as a recyclable heterogeneous catalyst for C-C coupling and reduction reactions in aqueous media. We also demonstrated that the in situ generated PdNPs containing trihybrid material was a more efficient catalyst than the trihybrid material generated with presynthesized PdNPs. PMID:27511441

  3. DWPF coupled feed flowsheet material balance with batch one sludge and copper nitrate catalyst

    SciTech Connect

    Choi, A.S.

    1993-09-28

    The SRTC has formally transmitted a recommendation to DWPF to replace copper formate with copper nitrate as the catalyst form during precipitate hydrolysis [1]. The SRTC was subsequently requested to formally document the technical bases for the recommendation. A memorandum was issued on August 23, 1993 detailing the activities (and responsible individuals) necessary to address the impact of this change in catalyst form on process compatibility, safety, processibility environmental impact and product glass quality [2]. One of the activities identified was the preparation of a material balance in which copper nitrate is substituted for copper formate and the identification of key comparisons between this material balance and the current Batch 1 sludge -- Late Wash material balance [3].

  4. Recognition of wall materials through active thermography coupled with numerical simulations.

    PubMed

    Pietrarca, Francesca; Mameli, Mauro; Filippeschi, Sauro; Fantozzi, Fabio

    2016-09-01

    In the framework of historical buildings, wall thickness as well as wall constituents are not often known a priori, and active IR thermography can be exploited as a nonintrusive method for detecting what kind of material lies beneath the external plaster layer. In the present work, the wall of a historical building is subjected to a heating stimulus, and the surface temperature temporal trend is recorded by an IR camera. A hybrid numerical model is developed in order to simulate the transient thermal response of a wall made of different known materials underneath the plaster layer. When the numerical thermal contrast and the appearance time match with the experimental thermal images, the material underneath the plaster can be qualitatively identified. PMID:27607254

  5. Quantification of uncertainties in coupled material degradation processes - High temperature, fatigue and creep

    NASA Technical Reports Server (NTRS)

    Boyce, L.; Chamis, C. C.

    1991-01-01

    This paper describes the development of methodology that provides for quantification of uncertainties in lifetime strength of aerospace materials subjected to a number of diverse effects. A probabilistic material degradation model, in the form of a randomized multifactor interaction equation, has been postulated for lifetime strength degradation of structural components of aerospace propulsion systems. The model includes effects that typically reduce lifetime strength and may include temperature, mechanical fatigue, creep and others. The paper also includes the analysis of experimental data from the open literature for Inconel 718. These data are used to provide an initial check for model validity, as well as for calibration of the model's empirical material constants. The model validity check and calibration is carried out for three effects, namely, high temperature, mechanical fatigue and creep.

  6. Ultrasonic Air-Coupled Inspection of Textile Materials Using Ferroelectret-Based Phased Arrays

    NASA Astrophysics Data System (ADS)

    Ealo, J.; Camacho, J.; Seco, F.; Fritsch, C.

    2010-02-01

    Most common defects in textile manufacturing processes include weaving errors (such as missing threads), oil spots and material inhomogeneities. In this work, we demonstrate the feasibility of using ferroelectret-based transducers for the inspection of woven material. A linear array of 32 elements was built for this purpose following an easy fabrication procedure recently proposed. Electronic focusing at the textile sample position allowed us to detect weaving errors and oil spots of up to ˜1 mm of width in through transmission mode, at normal incidence and with a good signal-to-noise ratio.

  7. Determination of organomercury in biological reference materials by inductively coupled plasma mass spectrometry using flow injection analysis

    SciTech Connect

    Beauchemin, D.; Siu, K.W.; Berman, S.S.

    1988-12-01

    Inductively coupled plasma mass spectrometry was used for the determination of organomercury in two marine biological standard reference materials for trace metals (dogfish muscle tissue DORM-1 and lobster hepatopancreas TORT-1). In most parts of this study, the organomercury was extracted as the chloride from the material with toluene and back extracted into an aqueous medium of cysteine acetate. Since the final extracts contained more than 4% sodium, isotope dilution and flow injection analysis were used to respectively counter the effect of concomitant elements and avoid clogging the interface. Comparison of results with gas chromatography shows that the only significant organomercury is methyl-mercury. At least 93% of mercury in DORM-1 and 39% of mercury in TORT-1 exist as methylmercury.

  8. Constructive spin-orbital angular momentum coupling can twist materials to create spiral structures in optical vortex illumination

    NASA Astrophysics Data System (ADS)

    Barada, Daisuke; Juman, Guzhaliayi; Yoshida, Itsuki; Miyamoto, Katsuhiko; Kawata, Shigeo; Ohno, Seigo; Omatsu, Takashige

    2016-02-01

    It was discovered that optical vortices twist isotropic and homogenous materials, e.g., azo-polymer films to form spiral structures on a nano- or micro-scale. However, the formation mechanism has not yet been established theoretically. To understand the mechanism of the spiral surface relief formation in the azo-polymer film, we theoretically investigate the optical radiation force induced in an isotropic and homogeneous material under irradiation using a continuous-wave optical vortex with arbitrary topological charge and polarization. It is revealed that the spiral surface relief formation in azo-polymer films requires the irradiation of optical vortices with a positive (negative) spin angular momentum and a positive (negative) orbital angular momentum (constructive spin-orbital angular momentum coupling), i.e., the degeneracy among the optical vortices with the same total angular momentum is resolved.

  9. Fundamentals of planar-type inductively coupled thermal plasmas on a substrate for large-area material processing

    NASA Astrophysics Data System (ADS)

    Tial, Mai Kai Suan; Irie, Hiromitsu; Maruyama, Yuji; Tanaka, Yasunori; Uesugi, Yoshihiko; Ishijima, Tatsuo

    2016-07-01

    In this work, the fundamentals of planar-type Ar inductively coupled thermal plasmas (ICTPs) with oxygen molecular gas on a substrate have been studied. Previously, aiming at large-area material processing, we developed a planar-type ICTP torch with a rectangular quartz vessel instead of a conventional cylindrical tube. For the adoption of such planar-type ICTP to material processing, it is necessary to sustain the ICTP with molecular gases on a substrate stably and uniformly. To determine the uniformity of the ICTP formed on the substrate, spectroscopic observation was carried out at 3 mm above the substrate. Results showed that the radiation intensities of specified O atomic lines were almost uniformly detected along the surface of the substrate. This means that excited O atoms, which are important radicals for thermal plasma oxidation, are present in the planar-type ICTP uniformly on the substrate.

  10. Coupling Hollow Fe3O4-Fe Nanoparticles with Graphene Sheets for High-Performance Electromagnetic Wave Absorbing Material.

    PubMed

    Qu, Bin; Zhu, Chunling; Li, Chunyan; Zhang, Xitian; Chen, Yujin

    2016-02-17

    We developed a strategy for coupling hollow Fe3O4-Fe nanoparticles with graphene sheets for high-performance electromagnetic wave absorbing material. The hollow Fe3O4-Fe nanoparticles with average diameter and shell thickness of 20 and 8 nm, respectively, were uniformly anchored on the graphene sheets without obvious aggregation. The minimal reflection loss RL values of the composite could reach -30 dB at the absorber thickness ranging from 2.0 to 5.0 mm, greatly superior to the solid Fe3O4-Fe/G composite and most magnetic EM wave absorbing materials recently reported. Moreover, the addition amount of the composite into paraffin matrix was only 18 wt %. PMID:26829291

  11. UMAT Implementation of Coupled, Multilevel, Structural Deformation and Damage Analysis of General Hereditary Materials

    NASA Technical Reports Server (NTRS)

    Arnold, S. M.; Saleeb, A. F.; Wilt, T. E.; Trowbridge, D.

    2000-01-01

    Extensive research efforts have been made over the years on the phenomenological representations of constitutive material behavior in the inelastic analysis and life assessment of structures composed of advanced monolithic and composite (CMC, MMC, and PMC) materials. Recently, emphasis has been placed on concurrently addressing three important and related areas of constitutive and degradation modeling; i.e. (i) mathematical formulation, (ii) algorithmic developments for the updating (integrating) of external (e.g. stress) and internal state variable, as well as (iii) parameter estimation for the characterization of the specific model. This concurrent perspective has resulted in; i) the formulation of a fully-associative viscoelastoplastic model (GVIPS), (ii) development of an efficient implicit integration and it's associative, symmetric, consistent tangent stiffness matrix algorithm for integration of the underlying rate flow/evolutionary equations, and iii) a robust, stand-alone, Constitutive Material Parameter Estimator (COMPARE) for automatically characterizing the various time-dependent, nonlinear, material models. Furthermore, to provide a robust multi-scale framework for the deformation and life analysis of structures composed of composite materials, NASA Glenn has aggressively pursued the development of a sufficiently general, accurate, and efficient micromechanics approach known as the generalized method of cells (GMC). This work has resulted in the development of MAC/GMC, a stand-alone micromechanics analysis tool that can easily and accurately design/analyze multiphase (composite) materials subjected to complex histories. MAC/GMC admits generalized, physically based, deformation and damage models for each constituent and provides "closed-form" expressions for the macroscopic composite response in terms of the properties, size, shape, distribution, and response of the individual constituents or phases that comprise the material. Consequently, MAC/GMC can

  12. Classification of spin liquids in materials with strong spin-orbit coupling

    NASA Astrophysics Data System (ADS)

    Reuther, Johannes; Lee, Shu-Ping; Alicea, Jason

    2014-03-01

    The investigation of spin liquids is a fascinating field in condensed matter physics that is increasingly motivated by experiments. Exhaustive classifications of spin liquids have been carried out in several systems, particularly when full SU(2) spin-rotation symmetry is present. Systematic studies that explore strongly spin-orbit-coupled magnetic compounds (for which there are many experimental examples) are, however, relatively scarce. We report on a classification of Z2 spin liquids on the square lattice when SU(2) spin symmetry is maximally lifted. Using projective symmetry group methods, we find that, surprisingly, the lifting of spin symmetry yields vastly more spin liquid states compared to SU(2)-invariant systems. Many of these spin liquids possess gapless edge states protected by lattice symmetries and, hence, constitute magnetic analogues of topological crystalline superconductors.

  13. Headspace single drop microextraction coupled with microwave extraction of essential oil from plant materials.

    PubMed

    Zhai, Yujuan; Sun, Shuo; Wang, Ziming; Zhang, Yupu; Liu, He; Sun, Ye; Zhang, Hanqi; Yu, Aimin

    2011-05-01

    Headspace single drop microextraction (HS-SDME) coupled with microwave extraction (ME) was developed and applied to the extraction of the essential oil from dried Syzygium aromaticum (L.) Merr. et Perry and Cuminum cyminum L. The operational parameters, such as microdrop volume, microwave absorption medium (MAM), extraction time, and microwave power were optimized. Ten microliters of decane was used as the microextraction solvent. Ionic liquid and carbonyl iron powder were used as MAM. The extraction time was less than 7 min at the microwave power of 440 W. The proposed method was compared with hydrodistillation (HD). There were no obvious differences in the constituents of essential oils obtained by the two methods. PMID:21416601

  14. Point defect modeling in materials: Coupling ab initio and elasticity approaches

    NASA Astrophysics Data System (ADS)

    Varvenne, Céline; Bruneval, Fabien; Marinica, Mihai-Cosmin; Clouet, Emmanuel

    2013-10-01

    Modeling point defects at an atomic scale requires careful treatment of the long-range atomic relaxations. This elastic field can strongly affect point defect properties calculated in atomistic simulations because of the finite size of the system under study. This is an important restriction for ab initio methods which are limited to a few hundred atoms. We propose an original approach coupling ab initio calculations and linear elasticity theory to obtain the properties of an isolated point defect for reduced supercell sizes. The reliability and benefit of our approach are demonstrated for three problematic cases: the self-interstitial in zirconium, clusters of self-interstitials in iron, and the neutral vacancy in silicon.

  15. Seismoelectric couplings in a poroelastic material containing two immiscible fluid phases

    NASA Astrophysics Data System (ADS)

    Jardani, A.; Revil, A.

    2015-08-01

    A new approach of seismoelectric imaging has been recently proposed to detect saturation fronts in which seismic waves are focused in the subsurface to scan its heterogeneous nature and determine saturation fronts. Such type of imaging requires however a complete modelling of the seismoelectric properties of porous media saturated by two immiscible fluid phases, one being usually electrically insulating (for instance water and oil). We combine an extension of Biot dynamic theory, valid for porous media containing two immiscible Newtonian fluids, with an extension of the electrokinetic theory based on the notion of effective volumetric charge densities dragged by the flow of each fluid phase. These effective charge densities can be related directly to the permeability and saturation of each fluid phase. The coupled partial differential equations are solved with the finite element method. We also derive analytically the transfer function connecting the macroscopic electrical field to the acceleration of the fast P wave (coseismic electrical field) and we study the influence of the water content on this coupling. We observe that the amplitude of the co-seismic electrical disturbance is very sensitive to the water content with an increase in amplitude with water saturation. We also investigate the seismoelectric conversions (interface effect) occurring at the water table. We show that the conversion response at the water table can be identifiable only when the saturation contrasts between the vadose and saturated zones are sharp enough. A relatively dry vadose zone represents the best condition to identify the water table through seismoelectric measurements. Indeed, in this case, the coseismic electrical disturbances are vanishingly small compared to the seismoelectric interface response.

  16. Enhancement of Goos-Hänchen effect in a prism-waveguide coupling system with magneto-optic material

    NASA Astrophysics Data System (ADS)

    Tang, Tingting; Deng, Longjiang; Qin, Jun; Bi, Lei

    2014-03-01

    We report a theoretical study of the enhancement of Goos-Hänchen (GH) effect in a prism-waveguide coupling system with magneto-optic materials, including dielectric waveguide (Prism/Air/Ce:YIG/SiO2) and plasmonic waveguide (Prism/Au/Ce:YIG/SiO2) structures. Giant GH shift is observed in both waveguides. By applying opposite magnetic field across the CeYIG layer, a variation of the GH shift, namely MOGH (magneto-optical Goos-Hänchen effect) is observed. Compared to the reflectivity and Goos-Hänchen effects of the structures, the MOGH effect shows higher sensitivity for index variations, therefore is very promising for chemical or biomedical index sensors. The device performance as a function of layer dimension, material refractive index and magneto-optical properties are simulated and discussed in detail. It is observed that coupling layer, MO layer thickness and prism index plays an important role in the plasmonic waveguide to control MOGH effect.

  17. New Effective Material Couple--Oxide Ceramic and Carbon Nanotube-- Developed for Aerospace Microsystem and Micromachine Technologies

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa; VanderWal, Randall L.; Tomasek, Aaron J.; Sayir, Ali; Farmer, Serene C.

    2004-01-01

    The prime driving force for using microsystem and micromachine technologies in transport vehicles, such as spacecraft, aircraft, and automobiles, is to reduce the weight, power consumption, and volume of components and systems to lower costs and increase affordability and reliability. However, a number of specific issues need to be addressed with respect to using microsystems and micromachines in aerospace applications--such as the lack of understanding of material characteristics; methods for producing and testing the materials in small batches; the limited proven durability and lifetime of current microcomponents, packaging, and interconnections; a cultural change with respect to system designs; and the use of embedded software, which will require new product assurance guidelines. In regards to material characteristics, there are significant adhesion, friction, and wear issues in using microdevices. Because these issues are directly related to surface phenomena, they cannot be scaled down linearly and they become increasingly important as the devices become smaller. When microsystems have contacting surfaces in relative motion, the adhesion and friction affect performance, energy consumption, wear damage, maintenance, lifetime and catastrophic failure, and reliability. Ceramics, for the most part, do not have inherently good friction and wear properties. For example, coefficients of friction in excess of 0.7 have been reported for ceramics and ceramic composite materials. Under Alternate Fuels Foundation Technologies funding, two-phase oxide ceramics developed for superior high-temperature wear resistance in NASA's High Operating Temperature Propulsion Components (HOTPC) project and new two-layered carbon nanotube (CNT) coatings (CNT topcoat/iron bondcoat/quartz substrate) developed in NASA's Revolutionary Aeropropulsion Concepts (RAC) project have been chosen as a materials couple for aerospace applications, including micromachines, in the nanotechnology

  18. Dictionary of Caribbean English Usage.

    ERIC Educational Resources Information Center

    Allsopp, Richard, Ed.

    This dictionary is designed to provide an inventory of English usage in the Caribbean environment and lifestyle as known and spoken in each territory but not recorded in the standard British and American desk dictionaries. It cross-references different names for the same item throughout the anglophone Caribbean, identifies different items called…

  19. Code Usage Analysis System (CUAS)

    NASA Technical Reports Server (NTRS)

    Horsley, P. H.; Oliver, J. D.

    1976-01-01

    A set of computer programs is offered to aid a user in evaluating performance of an application program. The system provides reports of subroutine usage, program errors, and segment loading which occurred during the execution of an application program. It is presented in support of the development and validation of the space vehicle dynamics project.

  20. Modeling Educational Usage of Facebook

    ERIC Educational Resources Information Center

    Mazman, Sacide Guzin; Usluel, Yasemin Kocak

    2010-01-01

    The purpose of this study is to design a structural model explaining how users could utilize Facebook for educational purposes. In order to shed light on the educational usage of Facebook, in constructing the model, the relationship between users' Facebook adoption processes and their educational use of Facebook were included indirectly while the…

  1. Coupling carbon nanomaterials with photochromic molecules for the generation of optically responsive materials

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoyan; Hou, Lili; Samorì, Paolo

    2016-04-01

    Multifunctional carbon-based nanomaterials offer routes towards the realization of smart and high-performing (opto)electronic (nano)devices, sensors and logic gates. Meanwhile photochromic molecules exhibit reversible transformation between two forms, induced by the absorption of electromagnetic radiation. By combining carbon-based nanomaterials with photochromic molecules, one can achieve reversible changes in geometrical structure, electronic properties and nanoscale mechanics triggering by light. This thus enables a reversible modulation of numerous physical and chemical properties of the carbon-based nanomaterials towards the fabrication of cognitive devices. This review examines the state of the art with respect to these responsive materials, and seeks to identify future directions for investigation.

  2. Coupled electrostatic and material surface stresses yield anomalous particle interactions and deformation

    NASA Astrophysics Data System (ADS)

    Kemp, B. A.; Nikolayev, I.; Sheppard, C. J.

    2016-04-01

    Like-charges repel, and opposite charges attract. This fundamental tenet is a result of Coulomb's law. However, the electrostatic interactions between dielectric particles remain topical due to observations of like-charged particle attraction and the self-assembly of colloidal systems. Here, we show, using both an approximate description and an exact solution of Maxwell's equations, that nonlinear charged particle forces result even for linear material systems and can be responsible for anomalous electrostatic interactions such as like-charged particle attraction and oppositely charged particle repulsion. Furthermore, these electrostatic interactions and the deformation of such particles have fundamental implications for our understanding of macroscopic electrodynamics.

  3. Automated in situ trace element analysis of silicate materials by laser ablation inductively coupled plasma mass spectrometry.

    PubMed

    Chen, Z; Canil, D; Longerich, H P

    2000-09-01

    This paper describes the automated in situ trace element analysis of solid materials by laser ablation (LA) inductively coupled plasma mass spectrometry (ICP-MS). A compact computer-controlled solid state Nd:YAG Merchantek EO UV laser ablation (LA) system has been coupled with the high sensitivity VG PQII S ICP-MS. A two-directional communication was interfaced in-house between the ICP-MS and the LA via serial RS-232 port. Each LA-ICP-MS analysis at a defined point includes a 60 s pre-ablation delay, a 60 s ablation, and a 90 s flush delay. The execution of each defined time setting by LA was corresponding to the ICP-MS data acquisition allowing samples to be run in automated cycle sequences like solution auto-sampler ICP-MS analysis. Each analytical cycle consists of four standards, one control reference material, and 15 samples, and requires about 70 min. Data produced by Time Resolved Analysis (TRA) from ICP-MS were later reduced off-line by in-house written software. Twenty-two trace elements from four reference materials (NIST SRM 613, and fused glass chips of BCR-2, SY-4, and G-2) were determined by the automated LA-ICP-MS method. NIST SRM 610 or NIST SRM 613 was used as an external calibration standard, and Ca as an internal standard to correct for drift, differences in transport efficiency and sampling yield. Except for Zr and Hf in G-2, relative standard deviations for all other elements are less than 10%. Results compare well with the data reported from literature with average limits of detection from 1 ng x g(-1) to 455 ng x g(-1) and less than 100 ng x g(-1) for most trace elements. PMID:11220835

  4. Influence of Surface Material on the BCl Density in Inductively Coupled Discharges

    SciTech Connect

    Blain, M.G.; Hamilton, T.W.; Hebner, G.A.

    1999-03-15

    The relative density of BCl radicals has been measured in a modified Applied Materials DPS metal etch chamber using laser-induced fluorescence. In plasmas containing mixtures of BCl{sub 3} with Cl{sub 2}, Ar and/or N{sub 2}, the relative BCl density was measured as a function of source and bias power, pressure, flow rate, BCl{sub 3}/Cl{sub 2} ratio and argon addition. To determine the influence of surface materials on the bulk plasma properties, the relative BCl density was measured using four different substrate types; aluminum, alumina, photoresist, and photoresist-patterned aluminum. In most cases, the relative BCl density was highest above photoresist-coated wafers and lowest above blanket aluminum wafers. The BCl density increased with increasing source power and the ratio of BCl{sub 3} to Cl{sub 2}, while the addition of N{sub 2} to a BCl{sub 3}/Cl{sub 2} plasma resulted in a decrease in BCl density. The BCl density was relatively insensitive to changes in the other plasma parameters.

  5. Correlation between charge transfer and exchange coupling in carbon-based magnetic materials

    SciTech Connect

    Nguyen, Anh Tuan; Nguyen, Van Thanh; Nguyen, Huy Sinh; Pham, Thi Tuan Anh; Do, Viet Thang; Dam, Hieu Chi

    2015-10-15

    Several forms of carbon-based magnetic materials, i.e. single radicals, radical dimers, and alternating stacks of radicals and diamagnetic molecules, have been investigated using density-functional theory with dispersion correction and full geometry optimization. Our calculated results demonstrate that the C{sub 31}H{sub 15} (R{sub 4}) radical has a spin of ½. However, in its [R{sub 4}]{sub 2} dimer structure, the net spin becomes zero due to antiferromagnetic spin-exchange between radicals. To avoid antiferromagnetic spin-exchange of identical face-to-face radicals, eight alternating stacks, R{sub 4}/D{sub 2m}/R{sub 4} (with m = 3-10), were designed. Our calculated results show that charge transfer (Δn) between R{sub 4} radicals and the diamagnetic molecule D{sub 2m} occurs with a mechanism of spin exchange (J) in stacks. The more electrons that transfer from R{sub 4} to D{sub 2m}, the stronger the ferromagnetic spin-exchange in stacks. In addition, our calculated results show that Δn can be tailored by adjusting the electron affinity (E{sub a}) of D{sub 2m}. The correlation between Δn, E{sub a}, m, and J is discussed. These results give some hints for the design of new ferromagnetic carbon-based materials.

  6. Coupling carbon nanomaterials with photochromic molecules for the generation of optically responsive materials

    PubMed Central

    Zhang, Xiaoyan; Hou, Lili; Samorì, Paolo

    2016-01-01

    Multifunctional carbon-based nanomaterials offer routes towards the realization of smart and high-performing (opto)electronic (nano)devices, sensors and logic gates. Meanwhile photochromic molecules exhibit reversible transformation between two forms, induced by the absorption of electromagnetic radiation. By combining carbon-based nanomaterials with photochromic molecules, one can achieve reversible changes in geometrical structure, electronic properties and nanoscale mechanics triggering by light. This thus enables a reversible modulation of numerous physical and chemical properties of the carbon-based nanomaterials towards the fabrication of cognitive devices. This review examines the state of the art with respect to these responsive materials, and seeks to identify future directions for investigation. PMID:27067387

  7. A modified implicit Monte Carlo method for time-dependent radiative transfer with adaptive material coupling

    SciTech Connect

    McClarren, Ryan G. Urbatsch, Todd J.

    2009-09-01

    In this paper we develop a robust implicit Monte Carlo (IMC) algorithm based on more accurately updating the linearized equilibrium radiation energy density. The method does not introduce oscillations in the solution and has the same limit as {delta}t{yields}{infinity} as the standard Fleck and Cummings IMC method. Moreover, the approach we introduce can be trivially added to current implementations of IMC by changing the definition of the Fleck factor. Using this new method we develop an adaptive scheme that uses either standard IMC or the modified method basing the adaptation on a zero-dimensional problem solved in each cell. Numerical results demonstrate that the new method can avoid the nonphysical overheating that occurs in standard IMC when the time step is large. The method also leads to decreased noise in the material temperature at the cost of a potential increase in the radiation temperature noise.

  8. Coupling carbon nanomaterials with photochromic molecules for the generation of optically responsive materials.

    PubMed

    Zhang, Xiaoyan; Hou, Lili; Samorì, Paolo

    2016-01-01

    Multifunctional carbon-based nanomaterials offer routes towards the realization of smart and high-performing (opto)electronic (nano)devices, sensors and logic gates. Meanwhile photochromic molecules exhibit reversible transformation between two forms, induced by the absorption of electromagnetic radiation. By combining carbon-based nanomaterials with photochromic molecules, one can achieve reversible changes in geometrical structure, electronic properties and nanoscale mechanics triggering by light. This thus enables a reversible modulation of numerous physical and chemical properties of the carbon-based nanomaterials towards the fabrication of cognitive devices. This review examines the state of the art with respect to these responsive materials, and seeks to identify future directions for investigation. PMID:27067387

  9. Rapid discrimination of plastic packaging materials using MIR spectroscopy coupled with independent components analysis (ICA)

    SciTech Connect

    Kassouf, Amine; Maalouly, Jacqueline; Rutledge, Douglas N.; Chebib, Hanna; Ducruet, Violette

    2014-11-15

    Highlights: • An innovative technique, MIR-ICA, was applied to plastic packaging separation. • This study was carried out on PE, PP, PS, PET and PLA plastic packaging materials. • ICA was applied to discriminate plastics and 100% separation rates were obtained. • Analyses performed on two spectrometers proved the reproducibility of the method. • MIR-ICA is a simple and fast technique allowing plastic identification/classification. - Abstract: Plastic packaging wastes increased considerably in recent decades, raising a major and serious public concern on political, economical and environmental levels. Dealing with this kind of problems is generally done by landfilling and energy recovery. However, these two methods are becoming more and more expensive, hazardous to the public health and the environment. Therefore, recycling is gaining worldwide consideration as a solution to decrease the growing volume of plastic packaging wastes and simultaneously reduce the consumption of oil required to produce virgin resin. Nevertheless, a major shortage is encountered in recycling which is related to the sorting of plastic wastes. In this paper, a feasibility study was performed in order to test the potential of an innovative approach combining mid infrared (MIR) spectroscopy with independent components analysis (ICA), as a simple and fast approach which could achieve high separation rates. This approach (MIR-ICA) gave 100% discrimination rates in the separation of all studied plastics: polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS) and polylactide (PLA). In addition, some more specific discriminations were obtained separating plastic materials belonging to the same polymer family e.g. high density polyethylene (HDPE) from low density polyethylene (LDPE). High discrimination rates were obtained despite the heterogeneity among samples especially differences in colors, thicknesses and surface textures. The reproducibility of

  10. Multielemental analysis in small amounts of environmental reference materials with inductively coupled plasma mass spectrometry.

    PubMed

    Dombovári, J; Becker, J S; Dietze, H J

    2000-07-01

    The lowest possible sample weight for performing multielemental trace element analysis on environmental and biological samples by ICP-MS has been investigated. The certified reference materials Bovine Liver NIST SRM 1577b, Human Hair NCS DC 73347 and Oriental Tobacco Leaves CTA-OTL-1 were applied at sample weights (1, 5, 20 and 50 mg aliquots, n = 10) which were significantly lower than those recommended with most recoveries in the range of 95-110%. Samples were digested in a mixture of nitric acid, hydrogen peroxide and hydrogen fluoride by closed-vessel microwave digestion. Multielemental analysis was performed with an optimized ICP-QMS method. Aqueous standard solutions were applied for external calibration with rhodium as the internal standard element. The detection limits varied between 0.02-0.38 microg/g for Li, Na, Cr, Mn, Ni, Cu, Zn, Sr, Cd, Ba and Pb, and up to 1.92 microg/g for Mg, Al, Ca, Fe and Ni. Digested human plasma samples were spiked with multielemental solution (0.5-10 microg/L) to test the analytical method and the recoveries were 95-105% for most analytes. Our results show that in the case of homogeneous SRMs it is possible to use them in very low amounts (1-5 mg) for method development and quality control. PMID:11227466

  11. Measuring Inductive-Heating Coupling Coefficients and Thermal Loss Characteristics as a Function of Crucible Geometry and Material Selection

    NASA Astrophysics Data System (ADS)

    Gomes, Jay

    A power measurement system has been designed for an ultra-high temperature inductively heated molten oxide electrolysis (MOE) reactor. The work presented in this research contributes to three different aspects of the induction heated MOE reactor facility: mathematical modeling of coil-to-workpiece power transfer, numerical modeling of heat transfer within the reactor, and experiments to measure the total hemispherical emittance of potential crucible materials. Facility-specific coupling coefficients for various samples have been experimentally determined for the MOE reactor facility. An analytical model coupling the predicted power input with heat transfer software was developed using COMSOL Multiphysics, and validated with experimental measurements of the steady state temperature gradient inside the reactor. These models were used to support the design of an experiment to measure the total hemispherical emissivity (epsilon) of conductive samples using a transient calorimetric technique. Results of epsilon are presented over a wide range of temperatures for copper, nickel, graphite and molybdenum. Furthermore, an investigation into optimizing the reactor system for heating will be discussed.

  12. C60 as an Active Smart Spacer Material on Silver Thin Film Substrates for Enhanced Surface Plasmon Coupled Emission

    PubMed Central

    Mulpur, Pradyumna; Podila, Ramakrishna; Ramamurthy, Sai Sathish; Kamisetti, Venkataramaniah; Rao, Apparao M.

    2015-01-01

    In this study, we present the use of C60 as an active spacer material on a silver (Ag) based surface plasmon coupled emission (SPCE) platform. In addition to its primary role of protecting the Ag thin film from oxidation, the incorporation of C60 facilitated the achievement of 30-fold enhancement in the emission intensity of rhodamine b (RhB) fluorophore. The high signal yield was attributed to the unique π-π interactions between C60 thin films and RhB, which enabled efficient transfer of energy of RhB emission to Ag plasmon modes. Furthermore, minor variations in the C60 film thickness yielded large changes in the enhancement and angularity properties of the SPCE signal, which can be exploited for sensing applications. Finally, the low-cost fabrication process of the Ag-C60 thin film stacks render C60 based SPCE substrates ideal, for the economic and simplistic detection of analytes. PMID:25785916

  13. Weather dissemination and public usage

    NASA Technical Reports Server (NTRS)

    Stacey, M. S.

    1973-01-01

    The existing public usage of weather information was examined. A survey was conducted to substantiate the general public's needs for dissemination of current (0-12 hours) weather information, needs which, in a previous study, were found to be extensive and urgent. The goal of the study was to discover how the general public obtains weather information, what information they seek and why they seek it, to what use this information is put, and to further ascertain the public's attitudes and beliefs regarding weather reporting and the diffusion of weather information. Major findings from the study include: 1. The public has a real need for weather information in the 0-6 hour bracket. 2. The visual medium is preferred but due to the lack of frequent (0-6 hours) forecasts, the audio media only, i.e., telephone recordings and radio weathercasts, were more frequently used. 3. Weather information usage is sporadic.

  14. GPU architecture usage for efficient image scaling

    NASA Astrophysics Data System (ADS)

    Skakov, P.

    2013-05-01

    Specifics of graphics processing units (GPU) architecture is considered. Opportunities of relevant optimization for image processing algorithms are presented such as usage of texture filtering block. Accuracy of image scaling and drivers influenced usage specifics are noted.

  15. Rapid discrimination of plastic packaging materials using MIR spectroscopy coupled with independent components analysis (ICA).

    PubMed

    Kassouf, Amine; Maalouly, Jacqueline; Rutledge, Douglas N; Chebib, Hanna; Ducruet, Violette

    2014-11-01

    Plastic packaging wastes increased considerably in recent decades, raising a major and serious public concern on political, economical and environmental levels. Dealing with this kind of problems is generally done by landfilling and energy recovery. However, these two methods are becoming more and more expensive, hazardous to the public health and the environment. Therefore, recycling is gaining worldwide consideration as a solution to decrease the growing volume of plastic packaging wastes and simultaneously reduce the consumption of oil required to produce virgin resin. Nevertheless, a major shortage is encountered in recycling which is related to the sorting of plastic wastes. In this paper, a feasibility study was performed in order to test the potential of an innovative approach combining mid infrared (MIR) spectroscopy with independent components analysis (ICA), as a simple and fast approach which could achieve high separation rates. This approach (MIR-ICA) gave 100% discrimination rates in the separation of all studied plastics: polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS) and polylactide (PLA). In addition, some more specific discriminations were obtained separating plastic materials belonging to the same polymer family e.g. high density polyethylene (HDPE) from low density polyethylene (LDPE). High discrimination rates were obtained despite the heterogeneity among samples especially differences in colors, thicknesses and surface textures. The reproducibility of the proposed approach was also tested using two spectrometers with considerable differences in their sensitivities. Discrimination rates were not affected proving that the developed approach could be extrapolated to different spectrometers. MIR combined with ICA is a promising tool for plastic waste separation that can help improve performance in this field; however further technological improvements and developments are required before it can be applied

  16. Opportunistic Resource Usage in CMS

    SciTech Connect

    Kreuzer, Peter; Hufnagel, Dirk; Dykstra, D.; Gutsche, O.; Tadel, M.; Sfiligoi, I.; Letts, J.; Wuerthwein, F.; McCrea, A.; Bockelman, B.; Fajardo, E.; Linares, L.; Wagner, R.; Konstantinov, P.; Blumenfeld, B.; Bradley, D.

    2014-01-01

    CMS is using a tiered setup of dedicated computing resources provided by sites distributed over the world and organized in WLCG. These sites pledge resources to CMS and are preparing them especially for CMS to run the experiment's applications. But there are more resources available opportunistically both on the GRID and in local university and research clusters which can be used for CMS applications. We will present CMS' strategy to use opportunistic resources and prepare them dynamically to run CMS applications. CMS is able to run its applications on resources that can be reached through the GRID, through EC2 compliant cloud interfaces. Even resources that can be used through ssh login nodes can be harnessed. All of these usage modes are integrated transparently into the GlideIn WMS submission infrastructure, which is the basis of CMS' opportunistic resource usage strategy. Technologies like Parrot to mount the software distribution via CVMFS and xrootd for access to data and simulation samples via the WAN are used and will be described. We will summarize the experience with opportunistic resource usage and give an outlook for the restart of LHC data taking in 2015.

  17. Opportunistic Resource Usage in CMS

    NASA Astrophysics Data System (ADS)

    Kreuzer, Peter; Hufnagel, Dirk; Dykstra, D.; Gutsche, O.; Tadel, M.; Sfiligoi, I.; Letts, J.; Wuerthwein, F.; McCrea, A.; Bockelman, B.; Fajardo, E.; Linares, L.; Wagner, R.; Konstantinov, P.; Blumenfeld, B.; Bradley, D.; Cms Collaboration

    2014-06-01

    CMS is using a tiered setup of dedicated computing resources provided by sites distributed over the world and organized in WLCG. These sites pledge resources to CMS and are preparing them especially for CMS to run the experiment's applications. But there are more resources available opportunistically both on the GRID and in local university and research clusters which can be used for CMS applications. We will present CMS' strategy to use opportunistic resources and prepare them dynamically to run CMS applications. CMS is able to run its applications on resources that can be reached through the GRID, through EC2 compliant cloud interfaces. Even resources that can be used through ssh login nodes can be harnessed. All of these usage modes are integrated transparently into the GlideIn WMS submission infrastructure, which is the basis of CMS' opportunistic resource usage strategy. Technologies like Parrot to mount the software distribution via CVMFS and xrootd for access to data and simulation samples via the WAN are used and will be described. We will summarize the experience with opportunistic resource usage and give an outlook for the restart of LHC data taking in 2015.

  18. Accelerating bioelectric functional development of neural stem cells by graphene coupling: Implications for neural interfacing with conductive materials.

    PubMed

    Guo, Rongrong; Zhang, Shasha; Xiao, Miao; Qian, Fuping; He, Zuhong; Li, Dan; Zhang, Xiaoli; Li, Huawei; Yang, Xiaowei; Wang, Ming; Chai, Renjie; Tang, Mingliang

    2016-11-01

    In order to govern cell-specific behaviors in tissue engineering for neural repair and regeneration, a better understanding of material-cell interactions, especially the bioelectric functions, is extremely important. Graphene has been reported to be a potential candidate for use as a scaffold and neural interfacing material. However, the bioelectric evolvement of cell membranes on these conductive graphene substrates remains largely uninvestigated. In this study, we used a neural stem cell (NSC) model to explore the possible changes in membrane bioelectric properties - including resting membrane potentials and action potentials - and cell behaviors on graphene films under both proliferation and differentiation conditions. We used a combination of single-cell electrophysiological recordings and traditional cell biology techniques. Graphene did not affect the basic membrane electrical parameters (capacitance and input resistance), but resting membrane potentials of cells on graphene substrates were more strongly negative under both proliferation and differentiation conditions. Also, NSCs and their progeny on graphene substrates exhibited increased firing of action potentials during development compared to controls. However, graphene only slightly affected the electric characterizations of mature NSC progeny. The modulation of passive and active bioelectric properties on the graphene substrate was accompanied by enhanced NSC differentiation. Furthermore, spine density, synapse proteins expressions and synaptic activity were all increased in graphene group. Modeling of the electric field on conductive graphene substrates suggests that the electric field produced by the electronegative cell membrane is much higher on graphene substrates than that on control, and this might explain the observed changes of bioelectric development by graphene coupling. Our results indicate that graphene is able to accelerate NSC maturation during development, especially with regard to

  19. [Detection of Ethoprophos Using SERS Coupled with Magnetic Fe3O4/Ag Composite Materials].

    PubMed

    Yuan, Rong-hui; Liu, Wen-han; Teng, Yuan-jie; Nie, Jing; Ma, Su-zhen

    2015-05-01

    The magnetic Fe3O4/Ag composite materials were synthesized by reducing AgNO3 with sodium citrate in the presence of Fe3O4 which were prepared by co-precipitation firstly. The enrichment and extraction of ethoprophos assembled on Fe3O4/Ag were achieved with the applied magnetic field. The different concentrations of ethoprophos adsorbed on Fe3O4/Ag were analyzed by SERS and it was showed that the trace analysis of ethoprophos had been established, while the enhancement factor of probe molecules on Fe3O4/Ag was 1. 48 X 10(5). The structure and morphology of Fe3O4/Ag were characterized by UV-Vis, EDX and TEM. Compared with Ag, the UV-Vis absorption peak of Fe3O4/Ag shifted from 417 to 369 nm, and the UV-Vis of Fe3O4 almost had no characteristic absorption peak in this region. At the same time, it was showed that the surface properties of Fe3O4/Ag changed with Raman enhancement effect during the aggregation process of Ag around the surface of Fe3O4. Further EDX images of micro area element analysis suggested that the chemical composition of products were Ag, Fe and O while the Cu peak was from the copper mesh. In addition, TEM images indicated that the average particle size of Fe3O4 was between 30 and 60 nm with shape tended to be spherical. And the silver nanoparticles were attached to the Fe3O4 particles and agglomeration occured. Density functional theory calculations which can be applied to qualitative judgment of molecule was carried out to obtain the molecular optimization structure and theoretical Raman spectra. It was found that the stabilized SERS signals were detected under the saturated adsorption equilibrium after 15 min. Finally, Raman response of ethoprophos was achieved with lower than 2 X 10(-8) mol . L-1 , indicatint that the established method had reached the requirements of ethoprophos residues detection and could be used for analysis of sulfur-containing organophosphorus pesticide. PMID:26415443

  20. Expletive Deleted: A Study of Language Usage.

    ERIC Educational Resources Information Center

    Nykodym, Nick; Boyd, John A.

    The research findings of profane language usage need to be extended so that more may be learned about human communication. In order to establish profane language usage norms, eighty-six university students were asked to estimate their profane language usage in each of three categories (excretory, religious, and sexual) in reference to three…

  1. Adaptive coupling between damage mechanics and peridynamics: A route for objective simulation of material degradation up to complete failure

    NASA Astrophysics Data System (ADS)

    Han, Fei; Lubineau, Gilles; Azdoud, Yan

    2016-09-01

    The objective (mesh-independent) simulation of evolving discontinuities, such as cracks, remains a challenge. Current techniques are highly complex or involve intractable computational costs, making simulations up to complete failure difficult. We propose a framework as a new route toward solving this problem that adaptively couples local-continuum damage mechanics with peridynamics to objectively simulate all the steps that lead to material failure: damage nucleation, crack formation and propagation. Local-continuum damage mechanics successfully describes the degradation related to dispersed microdefects before the formation of a macrocrack. However, when damage localizes, it suffers spurious mesh dependency, making the simulation of macrocracks challenging. On the other hand, the peridynamic theory is promising for the simulation of fractures, as it naturally allows discontinuities in the displacement field. Here, we present a hybrid local-continuum damage/peridynamic model. Local-continuum damage mechanics is used to describe "volume" damage before localization. Once localization is detected at a point, the remaining part of the energy is dissipated through an adaptive peridynamic model capable of the transition to a "surface" degradation, typically a crack. We believe that this framework, which actually mimics the real physical process of crack formation, is the first bridge between continuum damage theories and peridynamics. Two-dimensional numerical examples are used to illustrate that an objective simulation of material failure can be achieved by this method.

  2. Covalently Coupled Ultrafine H-TiO2 Nanocrystals/Nitrogen-Doped Graphene Hybrid Materials for High-Performance Supercapacitor.

    PubMed

    Yang, Shuhua; Lin, Yuan; Song, Xuefeng; Zhang, Peng; Gao, Lian

    2015-08-19

    Hydrogenated TiO2 (H-TiO2) are considered one of the most promising materials for supercapacitors given its low-cost, high conductivity, and enhanced electrochemical activity. However, the electrochemical performances of H-TiO2 due to lacking suitable structures is unsatisfactory, and thus how to design energetic H-TiO2-based electrode architectures still remains a great challenge. Herein, covalently coupled ultrafine H-TiO2 nanocrystals/nitrogen-doped graphene (H-TiO2/NG) hybrid materials were developed through a simple hydrothermal route followed by hydrogenation. Within this architecture, the strong interaction between H-TiO2 nanocrystals and NG sheets via covalent chemical bonding affords high structural stability inhibiting the aggregation of H-TiO2 nanocrystals. Meanwhile, the NG matrices function as an electrical highway and a mechanical backbone so that most of well-dispersed ultrafine H-TiO2 nanocrystals are electrochemically active but stable. As a result, the optimized H-TiO2/NG (H-TiO2/NG-B) exhibited high reversible specific capacity of 385.2 F g(-1) at 1 A g(-1), enhanced rate performance of 320.1 F g(-1) at a high current density of 10 A g(-1), and excellent cycling stability with 98.8% capacity retention. PMID:26214162

  3. Evaluation of the mineral profile of textile materials using inductively coupled plasma optical emission spectrometry and chemometrics.

    PubMed

    Menezes, E A; Carapelli, R; Bianchi, S R; Souza, S N P; Matos, W O; Pereira-Filho, E R; Nogueira, A R A

    2010-10-15

    The content of Al, Ba, Ca, Cr, Cu, Fe, Ni, P, Zn, Cd and Pb was determined in textile material samples after microwave-assisted decomposition in a cavity oven and extraction with an artificial sweat solution. Radial viewing inductively coupled plasma optical emission spectrometry (ICP OES) was the main detection technique, but Cd and Pb were determined by thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) to increase the sensitivity. Principal components analysis (PCA) was applied to the data sets to characterize the samples with respect to their geographic origin and color difference. The PCA for Brazilian single-color samples showed separation, with one group consisting of blue and green textiles and another with all the other materials evaluated. The geographic origin study showed a clear separation between Brazilian and Chinese textiles. The metals amount extracted with sweat extractable solution were lower than limits values pointed by the International Testing and Certification System for Textiles, Oko Tex Standard 100, in the all considered classes. Recoveries varied from 85 to 112% for additions ranging from 3.0 to 25 mg kg(-1) for Ca and from 0.3 to 7.0 mg kg(-1) for all other analytes through the microwave-assisted decomposition procedure. PMID:20599322

  4. On-line double isotope dilution laser ablation inductively coupled plasma mass spectrometry for the quantitative analysis of solid materials.

    PubMed

    Fernández, Beatriz; Rodríguez-González, Pablo; García Alonso, J Ignacio; Malherbe, Julien; García-Fonseca, Sergio; Pereiro, Rosario; Sanz-Medel, Alfredo

    2014-12-01

    We report on the determination of trace elements in solid samples by the combination of on-line double isotope dilution and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The proposed method requires the sequential analysis of the sample and a certified natural abundance standard by on-line IDMS using the same isotopically-enriched spike solution. In this way, the mass fraction of the analyte in the sample can be directly referred to the certified standard so the previous characterization of the spike solution is not required. To validate the procedure, Sr, Rb and Pb were determined in certified reference materials with different matrices, including silicate glasses (SRM 610, 612 and 614) and powdered samples (PACS-2, SRM 2710a, SRM 1944, SRM 2702 and SRM 2780). The analysis of powdered samples was carried out both by the preparation of pressed pellets and by lithium borate fusion. Experimental results for the analysis of powdered samples were in agreement with the certified values for all materials. Relative standard deviations in the range of 6-21% for pressed pellets and 3-21% for fused solids were obtained from n=3 independent measurements. Minimal sample preparation, data treatment and consumption of the isotopically-enriched isotopes are the main advantages of the method over previously reported approaches. PMID:25440666

  5. Infobutton usage in Patient Portal MyHealth

    PubMed Central

    Long, Jie; Hulse, Nathan C.; Tao, Cui

    2015-01-01

    Infobuttons have proven to be an important element in modern electronic health records (EHR), providing educational materials to both providers and patients. However, the usage of infobuttons in personalized health records (PHR) is only lightly documented in the literature. Patient-facing infobuttons pose a new challenge because patients have different questions and educational levels than professional users in EHRs. In this paper, we present usage data for patient-facing infobuttons that have recently been integrated in Intermountain Healthcare’s patient portal MyHealth. We summarize use patterns by usage classified in modules, electronic resources (eResource), and infobutton sessions. Based on the analysis, we propose further enhancements to the current implementation of infobuttons in MyHealth. PMID:26306251

  6. Gas Flow Tightly Coupled to Elastoplastic Geomechanics for Tight- and Shale-Gas Reservoirs: Material Failure and Enhanced Permeability

    DOE PAGESBeta

    Kim, Jihoon; Moridis, George J.

    2014-12-01

    We investigate coupled flow and geomechanics in gas production from extremely low permeability reservoirs such as tight and shale gas reservoirs, using dynamic porosity and permeability during numerical simulation. In particular, we take the intrinsic permeability as a step function of the status of material failure, and the permeability is updated every time step. We consider gas reservoirs with the vertical and horizontal primary fractures, employing the single and dynamic double porosity (dual continuum) models. We modify the multiple porosity constitutive relations for modeling the double porous continua for flow and geomechanics. The numerical results indicate that production of gasmore » causes redistribution of the effective stress fields, increasing the effective shear stress and resulting in plasticity. Shear failure occurs not only near the fracture tips but also away from the primary fractures, which indicates generation of secondary fractures. These secondary fractures increase the permeability significantly, and change the flow pattern, which in turn causes a change in distribution of geomechanical variables. From various numerical tests, we find that shear failure is enhanced by a large pressure drop at the production well, high Biot's coefficient, low frictional and dilation angles. Smaller spacing between the horizontal wells also contributes to faster secondary fracturing. When the dynamic double porosity model is used, we observe a faster evolution of the enhanced permeability areas than that obtained from the single porosity model, mainly due to a higher permeability of the fractures in the double porosity model. These complicated physics for stress sensitive reservoirs cannot properly be captured by the uncoupled or flow-only simulation, and thus tightly coupled flow and geomechanical models are highly recommended to accurately describe the reservoir behavior during gas production in tight and shale gas reservoirs and to smartly design

  7. Gas Flow Tightly Coupled to Elastoplastic Geomechanics for Tight- and Shale-Gas Reservoirs: Material Failure and Enhanced Permeability

    SciTech Connect

    Kim, Jihoon; Moridis, George J.

    2014-12-01

    We investigate coupled flow and geomechanics in gas production from extremely low permeability reservoirs such as tight and shale gas reservoirs, using dynamic porosity and permeability during numerical simulation. In particular, we take the intrinsic permeability as a step function of the status of material failure, and the permeability is updated every time step. We consider gas reservoirs with the vertical and horizontal primary fractures, employing the single and dynamic double porosity (dual continuum) models. We modify the multiple porosity constitutive relations for modeling the double porous continua for flow and geomechanics. The numerical results indicate that production of gas causes redistribution of the effective stress fields, increasing the effective shear stress and resulting in plasticity. Shear failure occurs not only near the fracture tips but also away from the primary fractures, which indicates generation of secondary fractures. These secondary fractures increase the permeability significantly, and change the flow pattern, which in turn causes a change in distribution of geomechanical variables. From various numerical tests, we find that shear failure is enhanced by a large pressure drop at the production well, high Biot's coefficient, low frictional and dilation angles. Smaller spacing between the horizontal wells also contributes to faster secondary fracturing. When the dynamic double porosity model is used, we observe a faster evolution of the enhanced permeability areas than that obtained from the single porosity model, mainly due to a higher permeability of the fractures in the double porosity model. These complicated physics for stress sensitive reservoirs cannot properly be captured by the uncoupled or flow-only simulation, and thus tightly coupled flow and geomechanical models are highly recommended to accurately describe the reservoir behavior during gas production in tight and shale gas reservoirs and to smartly design production

  8. First-principles method for electron-phonon coupling and electron mobility: Applications to two-dimensional materials

    NASA Astrophysics Data System (ADS)

    Gunst, Tue; Markussen, Troels; Stokbro, Kurt; Brandbyge, Mads

    2016-01-01

    We present density functional theory calculations of the phonon-limited mobility in n -type monolayer graphene, silicene, and MoS2. The material properties, including the electron-phonon interaction, are calculated from first principles. We provide a detailed description of the normalized full-band relaxation time approximation for the linearized Boltzmann transport equation (BTE) that includes inelastic scattering processes. The bulk electron-phonon coupling is evaluated by a supercell method. The method employed is fully numerical and does therefore not require a semianalytic treatment of part of the problem and, importantly, it keeps the anisotropy information stored in the coupling as well as the band structure. In addition, we perform calculations of the low-field mobility and its dependence on carrier density and temperature to obtain a better understanding of transport in graphene, silicene, and monolayer MoS2. Unlike graphene, the carriers in silicene show strong interaction with the out-of-plane modes. We find that graphene has more than an order of magnitude higher mobility compared to silicene in the limit where the silicene out-of-plane interaction is reduced to zero (by substrate interaction, clamping, or similar). If the out-of-plane interaction is not actively reduced, the mobility of silicene will essentially be zero. For MoS2, we obtain several orders of magnitude lower mobilities compared to graphene in agreement with other recent theoretical results. The simulations illustrate the predictive capabilities of the newly implemented BTE solver applied in simulation tools based on first-principles and localized basis sets.

  9. Recycling of organic materials and solder from waste printed circuit boards by vacuum pyrolysis-centrifugation coupling technology.

    PubMed

    Zhou, Yihui; Wu, WenBiao; Qiu, Keqiang

    2011-12-01

    Here, we focused on the recycling of waste printed circuit boards (WPCBs) using vacuum pyrolysis-centrifugation coupling technology (VPCT) aiming to obtain valuable feedstock and resolve environmental pollution. The two types of WPCBs were pyrolysed at 600°C for 30 min under vacuum condition. During the pyrolysis process, the solder of WPCBs was separated and recovered when the temperature range was 400-600°C, and the rotating drum was rotated at 1000 rpm for 10 min. The type-A of WPCBs pyrolysed to form an average of 67.91 wt.% residue, 27.84 wt.% oil, and 4.25 wt.% gas; and pyrolysis of the type-B of WPCBs led to an average mass balance of 72.22 wt.% residue, 21.57 wt.% oil, and 6.21 wt.% gas. The GC-MS and FT-IR analyses showed that the two pyrolysis oils consisted mainly of phenols and substituted phenols. The pyrolysis oil can be used for fuel or chemical feedstock for further processing. The recovered solder can be recycled directly and it can also be a good resource of lead and tin for refining. The pyrolysis residues contained various metals, glass fibers and other inorganic materials, which could be recovered after further treatment. The pyrolysis gases consisted mainly of CO, CO(2), CH(4), and H(2), which could be collected and recycled. PMID:21840196

  10. Pilot study: Exposure and materiality of the secondary room and its impact in the impulse response of coupled-volume concert halls

    NASA Astrophysics Data System (ADS)

    Ermann, Michael; Johnson, Marty E.

    2002-05-01

    What does one room sound like when it is partially exposed to another (acoustically coupled)? More specifically, this research aims to quantify how operational and design decisions impact aural impressions in the design of concert halls with acoustical coupling. By adding a second room to a concert hall, and designing doors to control the sonic transparency between the two rooms, designers can create a new, coupled acoustic. Concert halls use coupling to achieve a variable, longer, and distinct reverberant quality for their musicians and listeners. For this study, a coupled-volume shoebox concert hall was conceived with a fixed geometric volume, form, and primary-room sound absorption. Aperture size and secondary-room sound-absorption levels were established as variables. Statistical analysis of sound decay in this simulated hall suggests a highly sensitive relationship between the double-sloped condition and (1) Architectural composition, as defined by the aperture size exposing the chamber and (2) Materiality, as defined by the sound absorbance in the coupled volume. Preliminary calculations indicate that the double-sloped sound decay condition only appears when the total aperture area is less than 1.5% of the total shoebox surface area and the average absorption coefficient of the coupled volume is less than 0.07.

  11. Modal Codon Usage: Assessing the Typical Codon Usage of a Genome

    PubMed Central

    Davis, James J.; Olsen, Gary J.

    2010-01-01

    Most genomes are heterogeneous in codon usage, so a codon usage study should start by defining the codon usage that is typical to the genome. Although this is commonly taken to be the genomewide average, we propose that the mode—the codon usage that matches the most genes—provides a more useful approximation of the typical codon usage of a genome. We provide a method for estimating the modal codon usage, which utilizes a continuous approximation to the number of matching genes and a simplex optimization. In a survey of bacterial and archaeal genomes, as many as 20% more of the genes in a given genome match the modal codon usage than the average codon usage. We use the mode to examine the evolution of the multireplicon genomes of Agrobacterium tumefaciens C58 and Borrelia burgdorferi B31. In A. tumefaciens, the circular and linear chromosomes are characterized by a common “chromosome-like” codon usage, whereas both plasmids share a distinct “plasmid-like” codon usage. In B. burgdorferi, in addition to different codon-usage biases on the leading and lagging strands of DNA replication found by McInerney (McInerney JO. 1998. Replicational and transcriptional selection on codon usage in Borrelia burgdorferi. Proc Natl Acad Sci USA. 95:10698–10703), we also detect a codon-usage similarity between linear plasmid lp38 and the leading strand of the chromosome and a high similarity among the cp32 family of plasmids. PMID:20018979

  12. The effect of dielectric top lids on materials processing in a low frequency inductively coupled plasma (LF-ICP) reactor

    NASA Astrophysics Data System (ADS)

    Lim, J. W. M.; Chan, C. S.; Xu, L.; Xu, S.

    2014-08-01

    The advent of the plasma revolution began in the 1970's with the exploitation of plasma sources for anisotropic etching and processing of materials. In recent years, plasma processing has gained popularity, with research institutions adopting projects in the field and industries implementing dry processing in their production lines. The advantages of utilizing plasma sources would be uniform processing over a large exposed surface area, and the reduction of toxic emissions. This leads to reduced costs borne by manufacturers which could be passed down as consumer savings, and a reduction in negative environmental impacts. Yet, one constraint that plagues the industry would be the control of contaminants in a plasma reactor which becomes evident when reactions are conducted in a clean vacuum environment. In this work, amorphous silicon (a-Si) thin films were grown on glass substrates in a low frequency inductively coupled plasma (LF-ICP) reactor with a top lid made of quartz. Even though the chamber was kept at high vacuum ( 10-4 Pa), it was evident through secondary ion mass spectroscopy (SIMS) and Fourier-transform infra-red spectroscopy (FTIR) that oxygen contaminants were present. With the aid of optical emission spectroscopy (OES) the contaminant species were identified. The design of the LF-ICP reactor was then modified to incorporate an Alumina (Al2O3) lid. Results indicate that there were reduced amounts of contaminants present in the reactor, and that an added benefit of increased power transfer to the plasma, improving deposition rate of thin films was realized. The results of this study is conclusive in showing that Al2O3 is a good alternative as a top-lid of an LF-ICP reactor, and offers industries a solution in improving quality and rate of growth of thin films.

  13. Organizations and E-Mail Usage.

    ERIC Educational Resources Information Center

    Krapels, Roberta H.; Moss, Frederick K.

    1997-01-01

    Argues that, with increasing interest in electronic communications, e-mail usage by employees becomes critical to teaching business communication issues. Presents interview results from three different types of businesses regarding employee e-mail usage. Notes that interviewees had little negative to say about electronic messaging. (SR)

  14. Physical Educators' Technology Competencies and Usage

    ERIC Educational Resources Information Center

    Woods, Marianne L.; Goc Karp, Grace; Miao, Hui; Perlman, Dana

    2008-01-01

    The purpose of this study was to examine K-12 physical education teachers' perceptions of ability and usage of technology. Physical educators (n = 114) completed the Physical Education Technology Usage Survey assessing their perceived technology competency, how and why they utilize technology, challenges they face in implementing technology, and…

  15. Abnormal Web Usage Control by Proxy Strategies.

    ERIC Educational Resources Information Center

    Yu, Hsiang-Fu; Tseng, Li-Ming

    2002-01-01

    Approaches to designing a proxy server with Web usage control and to making the proxy server effective on local area networks are proposed to prevent abnormal Web access and to prioritize Web usage. A system is implemented to demonstrate the approaches. The implementation reveals that the proposed approaches are effective, such that the abnormal…

  16. Survey: Computer Usage in Design Courses.

    ERIC Educational Resources Information Center

    Henley, Ernest J.

    1983-01-01

    Presents results of a survey of chemical engineering departments regarding computer usage in senior design courses. Results are categorized according to: computer usage (use of process simulators, student-written programs, faculty-written or "canned" programs; costs (hard and soft money); and available software. Programs offered are listed in a…

  17. Food Supplement Usage by Adolescent Males.

    ERIC Educational Resources Information Center

    Fleischer, Barbara; Read, Marsha

    1982-01-01

    Adolescent males (N=568) responded to a questionnaire examining their food supplement usage, types of food supplements consumed, reasons for use and non-use, relationship of use to concern for health, and demographic and external factors influencing supplement use. Presents factors related to food supplement usage. (RC)

  18. Neurotic Anxiety, Pronoun Usage, and Stress

    ERIC Educational Resources Information Center

    Alban, Lewis Sigmund; Groman, William D.

    1976-01-01

    Attempts to clarify the function of a particular aspect of verbal communication, pronoun usage, by (a) using a Gestalt Therapy theory conceptual framework and (b) experimentally focusing on the relationship of pronoun usage to neurotic anxiety and emotional stress. (Author/RK)

  19. Definite Article Usage across Varieties of English

    ERIC Educational Resources Information Center

    Wahid, Ridwan

    2013-01-01

    This paper seeks to explore the extent of definite article usage variation in several varieties of English based on a classification of its usage types. An annotation scheme based on Hawkins and Prince was developed for this purpose. Using matching corpus data representing Inner Circle varieties and Outer Circle varieties, analysis was made on…

  20. Training the Medical Student in Computer Usage.

    ERIC Educational Resources Information Center

    Heard, Jr., John T.; Tritz, Gerald J.

    1982-01-01

    A method is detailed for introducing computer usage into any course in a medical curriculum and concomitantly stimulating student utilization of such technology. It is felt medicine will rely more heavily upon computer uses in the future, and that familiarity with computer technology provides confidence and competence in physician usage. (MP)

  1. Enhanced heat transfer through filler-polymer interface by surface-coupling agent in heat-dissipation material: A non-equilibrium molecular dynamics study

    SciTech Connect

    Tanaka, Kouichi; Ogata, Shuji; Kobayashi, Ryo; Tamura, Tomoyuki; Kitsunezuka, Masashi; Shinma, Atsushi

    2013-11-21

    Developing a composite material of polymers and micrometer-sized fillers with higher heat conductance is crucial to realize modular packaging of electronic components at higher densities. Enhancement mechanisms of the heat conductance of the polymer-filler interfaces by adding the surface-coupling agent in such a polymer composite material are investigated through the non-equilibrium molecular dynamics (MD) simulation. A simulation system is composed of α-alumina as the filler, bisphenol-A epoxy molecules as the polymers, and model molecules for the surface-coupling agent. The inter-atomic potential between the α-alumina and surface-coupling molecule, which is essential in the present MD simulation, is constructed to reproduce the calculated energies with the electronic density-functional theory. Through the non-equilibrium MD simulation runs, we find that the thermal resistance at the interface decreases significantly by increasing either number or lengths of the surface-coupling molecules and that the effective thermal conductivity of the system approaches to the theoretical value corresponding to zero thermal-resistance at the interface. Detailed analyses about the atomic configurations and local temperatures around the interface are performed to identify heat-transfer routes through the interface.

  2. Estimating toner usage with laser electrophotographic printers

    NASA Astrophysics Data System (ADS)

    Wang, Lu; Abramsohn, Dennis; Ives, Thom; Shaw, Mark; Allebach, Jan

    2013-02-01

    Accurate estimation of toner usage is an area of on-going importance for laser, electrophotographic (EP) printers. We propose a new two-stage approach in which we first predict on a pixel-by-pixel basis, the absorptance from printed and scanned pages. We then form a weighted sum of these pixel values to predict overall toner usage on the printed page. The weights are chosen by least-squares regression to toner usage measured with a set of printed test pages. Our twostage predictor significantly outperforms existing methods that are based on a simple pixel counting strategy in terms of both accuracy and robustness of the predictions.

  3. Explorating coupled production of dissolved organic material and methyl mercury in a tidal wetland using the intrinsic chemical composition of the organic material

    NASA Astrophysics Data System (ADS)

    Bergamaschi, B. A.; Fleck, J. A.; Downing, B.; Stephenson, M.; Hernes, P. J.; Boss, E.

    2007-12-01

    Elevated methyl mercury (MeHg) levels found in biota of the San Francisco Estuary have been attributed to methylation processes in the peat-rich tidal wetlands of the Estuary, where the concentration of dissolved organic matter (DOM) is tightly coupled to that of MeHg (r2=0.95). We sought to understand the geochemical processes that contribute to MeHg production by examining the composition of the co-occurring DOM. We measured spectral absorbance and fluorescence properties of DOM, as well as intrinsic chemical properties such as isotopic composition, lignin content, carbohydrate content, and bulk chemical functionality (by CPMAS-NMR). Carbon quality parameters independent of concentration such as specific UV absorbance, lignin abundance, aromatic content, biodegradability, and others were closely coupled to MeHg concentrations. This coupling, combined with the hydrologic forcing within the wetland, suggest that the zones of MeHg production are biogeochemically related to the zones of DOM release, thus providing a means to examine the underlying processes. The observed relationships were robust through the winter, spring, and fall seasons, despite a three- fold variation in MeHg and DOM concentration. The pattern of variation suggests sources of DOM and MeHg within peat pore waters rather than within the litter layer or water column. The various relationships with individual parameters will be discussed.

  4. College Student Credit Card Usage and Debt.

    ERIC Educational Resources Information Center

    Rybka, Kathryn M.

    2001-01-01

    Provides an overview of the concerns related to credit card usage by college students. Offers information student affairs professionals can use to help college students make responsible choices. (Contains 26 references.) (GCP)

  5. Understanding Road Usage Patterns in Urban Areas

    NASA Astrophysics Data System (ADS)

    Wang, Pu; Hunter, Timothy; Bayen, Alexandre M.; Schechtner, Katja; González, Marta C.

    2012-12-01

    In this paper, we combine the most complete record of daily mobility, based on large-scale mobile phone data, with detailed Geographic Information System (GIS) data, uncovering previously hidden patterns in urban road usage. We find that the major usage of each road segment can be traced to its own - surprisingly few - driver sources. Based on this finding we propose a network of road usage by defining a bipartite network framework, demonstrating that in contrast to traditional approaches, which define road importance solely by topological measures, the role of a road segment depends on both: its betweeness and its degree in the road usage network. Moreover, our ability to pinpoint the few driver sources contributing to the major traffic flow allows us to create a strategy that achieves a significant reduction of the travel time across the entire road system, compared to a benchmark approach.

  6. Families in a High-Tech Age: Technology Usage Patterns, Work and Family Correlates, and Gender

    ERIC Educational Resources Information Center

    Chesley, Noelle

    2006-01-01

    This study analyzes a couple-level ("N" = 581), longitudinal data set of employees to provide evidence about technology use over time, the factors that predict use, and the potential for a spouse to influence an individual's use. Although longitudinal usage patterns suggest a trend toward adoption and use of e-mail, the Internet, cell phones, and…

  7. Inductively coupled plasma mass spectrometry in comparison with neutron activation and ion chromatography with UV/VIS detection for the determination of lanthanides in plant materials.

    PubMed

    Bulska, Ewa; Danko, Bożena; Dybczyński, Rajmund S; Krata, Agnieszka; Kulisa, Krzysztof; Samczyński, Zbigniew; Wojciechowski, Marcin

    2012-08-15

    Analytical performance of inductively coupled plasma mass spectrometry (ICP-MS) for determination of lanthanides in plant materials was investigated and compared with neutron activation analysis (NAA) as well as ion chromatography (IC) with UV-VIS detection. Two sample preparation protocols were tested: (i) microwave assisted digestion by concentrated nitric acid; (ii) microwave digestion involving silica and fluoride removal, followed by the selective and quantitative lanthanides group separation from the plant matrix. Several Certified Reference Materials (CRM) of plant origin were used for the evaluation of the accuracy of the applied analytical procedures. The consistency of results, obtained by various methods, enabled to establish the tentative recommended values (TRV) for several missing elements in one of CRMs. The ICP-MS, due to its very high sensitivity, has the potential to contribute to this aim. The discrepancy of the results obtained by various methods was discussed in a view of possible matrix effects related to the composition of investigated materials. PMID:22841084

  8. The effect of context on synonymous codon usage in genes with low codon usage bias.

    PubMed Central

    Bulmer, M

    1990-01-01

    The effect of neighbouring bases on the usage of synonymous codons in genes with low codon usage bias in yeast and E. coli is examined. The codon adaptation index is employed to identify a group of genes in each organism with low codon usage bias, which are likely to be weakly expressed. A similar pattern is found in complementary sequences with respect to synonymous usage of A vs G or of U vs C. It is suggested that this may reflect an effect of context on mutation rates in weakly expressed genes. PMID:2190183

  9. Materialism.

    PubMed

    Melnyk, Andrew

    2012-05-01

    Materialism is nearly universally assumed by cognitive scientists. Intuitively, materialism says that a person's mental states are nothing over and above his or her material states, while dualism denies this. Philosophers have introduced concepts (e.g., realization and supervenience) to assist in formulating the theses of materialism and dualism with more precision, and distinguished among importantly different versions of each view (e.g., eliminative materialism, substance dualism, and emergentism). They have also clarified the logic of arguments that use empirical findings to support materialism. Finally, they have devised various objections to materialism, objections that therefore serve also as arguments for dualism. These objections typically center around two features of mental states that materialism has had trouble in accommodating. The first feature is intentionality, the property of representing, or being about, objects, properties, and states of affairs external to the mental states. The second feature is phenomenal consciousness, the property possessed by many mental states of there being something it is like for the subject of the mental state to be in that mental state. WIREs Cogn Sci 2012, 3:281-292. doi: 10.1002/wcs.1174 For further resources related to this article, please visit the WIREs website. PMID:26301463

  10. Reexamining Content-Enriched Access: Its Effect on Usage and Discovery

    ERIC Educational Resources Information Center

    Tosaka, Yuji; Weng, Cathy

    2011-01-01

    Content-enriched metadata in bibliographic records is considered helpful to library users in identifying and selecting library materials for their needs. The paper presents a study, using circulation data from a medium-sized academic library, of the effect of content-enriched records on library materials usage. The study also examines OPAC search…

  11. Worksheet Usage, Reading Achievement, Classes' Lack of Readiness, and Science Achievement: A Cross-Country Comparison

    ERIC Educational Resources Information Center

    Lee, Che-Di

    2014-01-01

    Instructional written materials play important roles as teachers' agents in effective teaching practices. Worksheets are one of the most frequently used materials. In this exploratory study, the relationships between worksheet usage and science achievement in 32 countries were examined through the use of TIMSS and PIRLS data and multiple…

  12. Economical and environmentally-friendly approaches for usage of onion (Allium cepa L.) waste.

    PubMed

    Sharma, Kavita; Mahato, Neelima; Nile, Shivraj Hariram; Lee, Eul Tal; Lee, Yong Rok

    2016-08-10

    Onion (Allium cepa L.) is one of the most commonly cultivated crops across the globe, and its production is increasing every year due to increasing consumer demand. Simultaneously, huge amounts of waste are produced from different parts of the onion, which ultimately affect the environment in various ways. Hence, proper usage as well as disposal of this waste is important from the environmental aspect. This review summarizes various usage methods of onion waste material, and processes involved to achieve maximum benefits. Processing industries produce the largest amount of onion waste. Other sources are storage systems, domestic usage and cultivation fields. Particular emphasis has been given to the methods used for better extraction and usage of onion waste under specific topics: viz. organic synthesis, production of biogas, absorbent for pollutants and value added products. PMID:27457732

  13. EBSCO's Usage Consolidation Attempts to Streamline Gathering, Storage, and Reporting of Usage Statistics

    ERIC Educational Resources Information Center

    Remy, Charlie

    2012-01-01

    This paper provides an overview of EBSCO's new Usage Consolidation product designed to streamline the harvesting, storage, and analysis of usage statistics from electronic resources. Strengths and weaknesses of the product are discussed as well as an early beta partner's experience. In the current atmosphere of flat or declining budgets, libraries…

  14. Manganese concentrate usage in steelmaking

    NASA Astrophysics Data System (ADS)

    Nokhrina, O. I.; Rozhihina, I. D.

    2015-09-01

    The results of the research process of producing metalized products by solid-phase reduction of iron using solid carbonaceous reducing agents. Thermodynamic modeling was carried out on the model of the unit the Fe-C-O and system with iron ore and coal. As a result of modeling the thermodynamic boundary reducing, oxidizing, and transition areas and the value of the ratio of carbon and oxygen in the system. Simulation of real systems carried out with the gas phase obtained in the pyrolys of coal. The simulation results allow to determine the optimal cost of coal required for complete reduction of iron ore from a given composition. The kinetics of the processes of solid-phase reduction of iron using coal of various technological brands. The paper describes experiments on effects of metal deoxidizer composition, component proportion, pelletizing mixture, particle size distribution of basic materials and flux on manganese recovering from oxides under direct melting.

  15. Magnetically coupled system for mixing

    SciTech Connect

    Miller, III, Harlan; Meichel, George; Legere, Edward; Malkiel, Edwin; Woods, Robert Paul; Ashley, Oliver; Katz, Joseph; Ward, Jason; Petersen, Paul

    2014-04-01

    The invention provides a mixing system comprising a magnetically coupled drive system and a foil for cultivating algae, or cyanobacteria, in an open or enclosed vessel. The invention provides effective mixing, low energy usage, low capital expenditure, and ease of drive system component maintenance while maintaining the integrity of a sealed mixing vessel.

  16. Magnetically coupled system for mixing

    SciTech Connect

    Miller, III, Harlan; Meichel, George; Legere, Edward; Malkiel, Edwin; Woods, Robert Paul; Ashley, Oliver; Katz, Joseph; Ward, Jason; Petersen, Paul

    2015-09-22

    The invention provides a mixing system comprising a magnetically coupled drive system and a foil for cultivating algae, or cyanobacteria, in an open or enclosed vessel. The invention provides effective mixing, low energy usage, low capital expenditure, and ease of drive system component maintenance while maintaining the integrity of a sealed mixing vessel.

  17. A global profile of replicative polymerase usage

    PubMed Central

    Müller, Carolin A.; Miyabe, Izumi; Brooks, Tony; Retkute, Renata; Hubank, Mike; Nieduszyski, Conrad A.; Carr, Antony M.

    2014-01-01

    Three eukaryotic DNA polymerases are essential for genome replication. Polα-primase initiates each synthesis event and is rapidly replaced by processive DNA polymerases: Polε replicates the leading strand while Polδ performs lagging strand synthesis. However, it is not known whether this division of labour is maintained across the whole genome or how uniform it is within single replicons. Using S. pombe, we have developed a polymerase usage sequencing (Pu-seq) strategy to map polymerase usage genome–wide. Pu–seq provides direct replication origin location and efficiency data and indirect estimates of replication timing. We confirm that the division of labour is broadly maintained across an entire genome. However, our data suggest a subtle variability in the usage of the two polymerases within individual replicons. We propose this results from occasional leading strand initiation by Polδ followed by exchange for Polε. PMID:25664722

  18. Worldwide trends in battery separator technology and usage

    NASA Astrophysics Data System (ADS)

    Weighall, M. J.

    This paper reviews trends in battery separator usage for starting-lighting-and-ignition (SLI), motive power, and sealed valve-regulated lead/acid batteries. For SLI batteries, the dominant trend in the USA and Western Europe has been a dramatic increase in polyethylene envelope separator usage, with other countries now following this trend. This is at the expense of traditional leaf-type separators such as cellulose or sintered polyvinyl chloride (PVC). For motive power applications, several different types of separator materials are currently favoured, including polyethylene, microporous rubber, microporous PVC and resin-impregnated polyester fibres. Worldwide trends in the motive power battery and separator market are shown. For sealed valve-regulated lead/acid batteries, the favoured construction uses a recombinant battery separator mat, normally of 100% borosilicate glass (binder free). Alternative mats containing a proportion of polymeric fibres are now being investigated. Market trends and factors affecting growth in the use of recombinant battery separator mats (RBSM) are reviewed. Results of mercury-intrusion porosimetry data for different separator materials are shown and reviewed. This technique provides an interesting way of differentiating between different separator materials based on their pore size distribution.

  19. A two-dimensional model on the coupling thickness-shear vibrations of a quartz crystal resonator loaded by an array spherical-cap viscoelastic material units.

    PubMed

    Xie, Jiemin; Hu, Yuantai

    2016-09-01

    We establish a two-dimensional model on the coupling thickness-shear mode (TSM) vibrations of a quartz crystal resonator (QCR) carrying an array of spherical-cap (SC) viscoelastic material units. The electrical admittance of the compound QCR system is described directly in terms of the physical properties of the surface material units. The admittance spectra about the tendon stem cells (TSCs) acquired from our calculation are compared with the existing experiment data and found to be consistent with each other, indicating our model has good veracity and reliability in analyzing the mechanical properties of covered loadings. Furthermore, we calculate admittance spectra of surface Epoxy Resin (SU-8) units with different geometrical configurations and bulk effect. It is found that both geometrical configuration and bulk effect produce influence on the resonant frequency and admittance of the compound QCR system. PMID:27393903

  20. Fundamental of a Planar Type of Inductively Coupled Thermal Plasma (ICTP) on a Substrate for a Large-area Materials Processings

    NASA Astrophysics Data System (ADS)

    Suantial, Maikai; Akao, Mika; Irie, Hiromitsu; Maruyama, Yuji; Tanaka, Yasunori; Uesugi, Yoshihiko; Ishijima, Tatsuo; Kanazawa University Team

    2015-09-01

    In this paper, the fundamental of a planar type Ar inductively coupled thermal plasmas (ICTP) with oxygen molecular gas have been studied on a substrate. Previously, we have developed a planar-ICTP torch with a rectangular quartz vessel with an air core coil or a ferrite core coil instead of a cylindrical tube for a large-area materials processing. For adoption of such a planar-ICTP to material processings, it needs to sustain the ICTP with molecular gases on a substrate stably. To consider the uniformity of the ICTP formed on the substrate, spectroscopic observation was carried out at 3 mm above the substrate. Results showed that the radiation intensities of specified O atomic lines were almost uniformly detected along the surface of the substrate. This means that O excited atoms, which are important radicals for thermal plasma oxidation, are present in planar-ICTP uniformly on the substrate.

  1. Fundamental Processes of Coupled Radiation Damage and Mechanical Behavior in Nuclear Fuel Materials for High Temperature Reactors

    SciTech Connect

    Phillpot, Simon; Tulenko, James

    2011-09-08

    The objective of this work has been to elucidate the relationship among microstructure, radiation damage and mechanical properties for nuclear fuel materials. As representative nuclear materials, we have taken an hcp metal (Mg as a generic metal, and Ti alloys for fast reactors) and UO2 (representing fuel). The degradation of the thermo-mechanical behavior of nuclear fuels under irradiation, both the fissionable material itself and its cladding, is a longstanding issue of critical importance to the nuclear industry. There are experimental indications that nanocrystalline metals and ceramics may be more resistant to radiation damage than their coarse-grained counterparts. The objective of this project look at the effect of microstructure on radiation damage and mechanical behavior in these materials. The approach to be taken was state-of-the-art, large-scale atomic-level simulation. This systematic simulation program of the effects of irradiation on the structure and mechanical properties of polycrystalline Ti and UO2 identified radiation damage mechanisms. Moreover, it will provided important insights into behavior that can be expected in nanocrystalline microstructures and, by extension, nanocomposites. The fundamental insights from this work can be expected to help in the design microstructures that are less susceptible to radiation damage and thermomechanical degradation.

  2. Galvanic coupling between D6AC steel, 6061-T6 aluminum, Inconel 718 and graphite-epoxy composite material: Corrosion occurrence and prevention

    NASA Technical Reports Server (NTRS)

    Danford, M. D.; Higgins, R. H.

    1983-01-01

    The effects of galvanic coupling between D6AC steel, 6061-T6 aluminum, Inconel 718, and graphite-epoxy composite material (G/E) in 3.5% NaCl were studied. Measurements of corrosion potentials, galvanic currents and corrosion rates of the bare metals using weight-loss methods served to establish the need for corrosion protection in cases where D6AC steel and 6061-T6 aluminum are galvanically coupled to G/E in salt water while Inconel 718 was shown to be compatible with G/E. Six tests were made to study corrosion protective methods for eliminating galvanic corrosion in the cases of D6AC steel and 6061-T6 aluminum coupled to G/E. These results indicate that, when the G/E is completely coated with paint or a paint/polyurethane resin combination, satisfactory protection of the D6AC steel is achieved with either a coat of zinc-rich primer or a primer/topcoat combination. Likewise, satisfactory corrosion protection of the aluminum is achieved by coating it with an epoxy coating system.

  3. Development and evaluation of materials for thermochemical heat storage based on the CaO/CaCO3 reaction couple

    NASA Astrophysics Data System (ADS)

    Sakellariou, Kyriaki G.; Tsongidis, Nikolaos I.; Karagiannakis, George; Konstandopoulos, Athanasios G.; Baciu, Diana; Charalambopoulou, Georgia; Steriotis, Theodore; Stubos, Athanasios; Arlt, Wolfgang

    2016-05-01

    The current work relates to the development of synthetic calcium oxide (CaO) based compositions as candidate materials for energy storage under a cyclic carbonation/decarbonation reaction scheme. Although under such a cyclic scheme the energy density of natural lime based CaO is high (˜ 3MJ/kg), the particular materials suffer from notable cycle-to-cycle deactivation. To this direction, pure CaO and CaO/Al2O3 composites have been prepared and preliminarily evaluated under the suggested cyclic carbonation/decarbonation scheme in the temperature range of 600-800°C. For the composite materials, Ca/Al molar ratios were in the range between 95/5 and 52/48 and upon calcination the formation of mixed Ca/Al phases was verified. The preliminary evaluation of materials studied was conducted under 3 carbonation/decarbonation cycles and the loss of activity for the case of natural CaO was obvious. Synthetic materials with superior stability/capture c.f. natural CaO were further subjected to multi-cyclic carbonation/decarbonation, via which the positive effect of alumina addition was made evident. Selected compositions exhibited adequately high CO2 capture capacity and stable performance during multi-cyclic operation. Moreover, this study contains preliminary experiments referring to proof-of-principle validation of a concept based on the utilization of a CaO-based honeycomb reactor/heat exchanger preliminary design. In particular, cordierite monolithic structures were coated with natural CaO and in total 11 cycles were conducted. Upon operation, clear signs of heat dissipation by the imposed flow in the duration of the exothermic reaction step were identified.

  4. Fabrication and application of a wireless inductance-capacitance coupling microsensor with electroplated high permeability material NiFe

    NASA Astrophysics Data System (ADS)

    Chen, Y. H.; Chang, H. C.; Lai, C. C.; Chang, I. N.

    2011-01-01

    A fully integrated wireless inductance-capacitance (LC) coupling microsensor was designed and fabricated by MEMS technology. The sensing loop was formed by connecting a deformable parallel-plated capacitor and a planar spiral inductor with a Ni(80)Fe(20) core. Polyimide and PMMA were used to isolate and package the devices. Typical dimension of the sensors was 5 × 5 mm2 × 0.77 mm. Different electroplated inductive coils (30, 40, and 60 turns) were fabricated to connect with a 4 × 4 mm2 plate capacitor in series. The LC sensing module for measuring liquid-level induced frequency responses was setup. Experimental results show that frequency response decreased as liquid level increased and sensitivity is about 7.01 kHz/cm with deviation less than 2%. Developed planar spiral inductor with high permeability magnetic core can provide a wide range of frequency variation in LC sensing applications.

  5. Nonanalytic behavior of the Casimir force across a Lifshitz transition in a spin-orbit-coupled material

    NASA Astrophysics Data System (ADS)

    Allocca, Andrew A.; Wilson, Justin H.; Galitski, Victor

    2014-08-01

    The Casimir effect is a fascinating phenomenon where quantum fluctuations of the electromagnetic field give rise to measurable forces between macroscopic systems. Here we propose that the Casimir effect can be used as a tool to detect changes in electronic structures. In particular, we focus here on the Lifshitz transition—a topological change in the Fermi surface—in a planar spin-orbit-coupled semiconductor in a magnetic field and calculate the Casimir force between the semiconductor and another probe system across the magnetic-field-tuned transition. We show that the Casimir force experiences a sharp kink at the topological transition and provide numerical estimates indicating that the effect is well within experimental reach. The simplest experimental realization of the proposed effect would involve a metal-coated sphere suspended from a microcantilever above a thin layer of InSb (or another semiconductor with a large g factor).

  6. NAT Usage in Residential Broadband Networks

    NASA Astrophysics Data System (ADS)

    Maier, Gregor; Schneider, Fabian; Feldmann, Anja

    Many Internet customers use network address translation (NAT) when connecting to the Internet. To understand the extend of NAT usage and its implications, we explore NAT usage in residential broadband networks based on observations from more than 20,000 DSL lines. We present a unique approach for detecting the presence of NAT and for estimating the number of hosts connected behind a NAT gateway using IP TTLs and HTTP user-agent strings. Furthermore, we study when each of the multiple hosts behind a single NAT gateway is active. This enables us to detect simultaneous use. In addition, we evaluate the accuracy of NAT analysis techniques when fewer information is available.

  7. A homogenization approach for characterization of the fluid-solid coupling parameters in Biot's equations for acoustic poroelastic materials

    NASA Astrophysics Data System (ADS)

    Gao, K.; van Dommelen, J. A. W.; Göransson, P.; Geers, M. G. D.

    2015-09-01

    In this paper, a homogenization method is proposed to obtain the parameters of Biot's poroelastic theory from a multiscale perspective. It is assumed that the behavior of a macroscopic material point can be captured through the response of a microscopic Representative Volume Element (RVE) consisting of both a solid skeleton and a gaseous fluid. The macroscopic governing equations are assumed to be Biot's poroelastic equations and the RVE is governed by the conservation of linear momentum and the adopted linear constitutive laws under the isothermal condition. With boundary conditions relying on the macroscopic solid displacement and fluid pressure, the homogenized solid stress and fluid displacement are obtained based on energy consistency. This homogenization framework offers an approach to obtain Biot's parameters directly through the response of the RVE in the regime of Darcy's flow where the pressure gradient is dominating. A numerical experiment is performed in the form of a sound absorption test on a porous material with an idealized partially open microstructure that is described by Biot's equations where the parameters are obtained through the proposed homogenization approach. The result is evaluated by comparison with Direct Numerical Simulations (DNS), showing a superior performance of this approach compared to an alternative semi-phenomenological model for estimating Biot's parameters of the studied porous material.

  8. Application of direct solid sample analysis for the determination of chlorine in biological materials using electrothermal vaporization inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    de Gois, Jefferson Santos; Pereira, Éderson R.; Welz, Bernhard; Borges, Daniel L. G.

    2015-03-01

    This work describes a methodology developed to carry out Cl determination in biological materials using electrothermal vaporization inductively coupled plasma mass spectrometry and direct solid sample analysis. The solid samples were directly weighed into graphite 'cups' and inserted into the graphite furnace. The RF power and the carrier gas flow rate were optimized at 1300 W and 0.7 L min- 1, respectively. Calibration could be carried out using aqueous standard solutions with pre-dried modifiers (Pd + Nd or Pd + Ca) or using solid certified reference materials with the same pre-dried modifiers or without the use of modifiers. The limit of quantification was determined as 5 μg g- 1 under optimized conditions and the Cl concentration was determined in five certified reference materials with certified concentrations for Cl, in addition to three certified reference materials, for which certified values for Cl were unavailable; in the latter case, the results were compared with those obtained using high-resolution continuum source molecular absorption spectrometry. Good agreement at a 95% statistical confidence level was achieved between determined and certified or reference values.

  9. The direct determination of trace metals in gold and silver materials by laser ablation inductively coupled plasma mass spectrometry without matrix matched standards

    NASA Astrophysics Data System (ADS)

    Kogan, Valentina V.; Hinds, Michael W.; Ramendik, Gregory I.

    1994-04-01

    Typically, accurate trace element determination in solid samples by laser ablation ICP-MS requires calibration with matrix matched standards. Trace metal analysis was performed in high purity gold, high purity silver and 14 karat gold-silver alloys. A Nd : YAG laser was used to evaporate solid samples of precious metals into an inductively coupled plasma mass spectrometer. Analytical data and a study of the crater sizes indicated that approximately the same amount of material for both gold and silver samples was vaporized by a Nd : YAG laser operated in a Q-switched mode with the following parameters: 210 mJ laser energy; 8 Hz repetition rate; and focused 7 mm below the sample surface. High purity gold and silver, and a 14 karat gold-silver alloy were analyzed for trace metals common to gold and silver reference materials. In general, the determination of Fe, Ni, Cu, Zn, Pd, Pt, Pb, and Bi did not strongly depend on whether gold or silver reference materials were used for calibration. This permits these trace metals to be determined directly with only one set of reference materials, by laser ablation ICP-MS, in a wide variety of gold-silver alloys.

  10. Female Athletes and Performance-Enhancer Usage

    ERIC Educational Resources Information Center

    Fralinger, Barbara K.; Pinto-Zipp, Genevieve; Olson, Valerie; Simpkins, Susan

    2007-01-01

    The purpose of this study was to develop a knowledge base on factors associated with performance-enhancer usage among female athletes at the high school level in order to identify markers for a future prevention-education program. The study used a pretest-only, between-subjects Likert Scale survey to rank the importance of internal and external…

  11. College Student Performance and Credit Card Usage.

    ERIC Educational Resources Information Center

    Pinto, Mary Beth; Parente, Diane H.; Palmer, Todd Starr

    2001-01-01

    Examines the relationship between credit card usage, employment, and academic performance among a group of college students with credit cards. Results reveal that the students differed significantly in the level of anxiety felt from carrying debt, perceived need to work, and perceived impact of employment on academic performance. (Contains 57…

  12. Twitter Usage of Universities in Turkey

    ERIC Educational Resources Information Center

    Yolcu, Ozgu

    2013-01-01

    Universities are among the users of the most popular social media networks. Usage of social media by especially students and many other people and institutions, which constitutes the target audience for universities, encourages the universities to effectively use this environment. Twitter is among these social media networks which facilitate the…

  13. [Dental welding titanium and its clinical usage].

    PubMed

    Li, H; Xiao, M; Zhao, Y

    1998-09-01

    Due to its excellent biocompatibility, desirable chemical and mechanical properties, Titanium has been used for implant denture, RPD and FPD, where welding techniques were indispensable. This paper introduces 5 useful modern ways to weld Titanium and their clinical usage. They are: laser, plasma welding, TIG, infraned brazing and Hruska electrowelding. PMID:12553259

  14. Nutritional supplements usage by Portuguese athletes.

    PubMed

    Sousa, Mónica; Fernandes, Maria João; Moreira, Pedro; Teixeira, Vítor Hugo

    2013-01-01

    In this study, we determined the prevalence of nutritional supplements (NS) usage, the type of supplements used, the reasons for usage, and the source of nutritional advice among Portuguese athletes. Two hundred ninety-two athletes (68 % male, 12 - 37 years old) from 13 national sports federations completed a questionnaire that sought information on socio-demographics, sports data, and NS usage. Most athletes (66 %) consumed NS, with a median consumption of 4 supplements per athlete. The most popular supplements included multivitamins/minerals (67 %), sport drinks (62 %), and magnesium (53 %). Significant differences for the type of NS consumed were found between gender and age groups and the number of weekly training hours. Most athletes used NS to accelerate recovery (63 %), improve sports performance (62 %), and have more energy/reduce fatigue (60 %). Athletes sought advice on supplementation mainly from physicians (56 %) and coaches (46 %). Age and gender were found to influence reasons for use and the source of information. Reasons for NS usage were supported scientifically in some cases (e. g., muscle gain upon protein supplementation), but others did not have a scientific basis (e. g., use of glutamine and magnesium). Given the high percentage of NS users, there is an urgent need to provide athletes with education and access to scientific and unbiased information, so that athletes can make assertive and rational choices about the utilization of these products. PMID:24220164

  15. Google Scholar Usage: An Academic Library's Experience

    ERIC Educational Resources Information Center

    Wang, Ya; Howard, Pamela

    2012-01-01

    Google Scholar is a free service that provides a simple way to broadly search for scholarly works and to connect patrons with the resources libraries provide. The researchers in this study analyzed Google Scholar usage data from 2006 for three library tools at San Francisco State University: SFX link resolver, Web Access Management proxy server,…

  16. Codon usage trend in mitochondrial CYB gene.

    PubMed

    Uddin, Arif; Chakraborty, Supriyo

    2016-07-15

    Here we reported the pattern of codon usage and the factors which influenced the codon usage pattern in mitochondrial cytochrome B (MT-CYB) gene among pisces, aves and mammals. The F1 axis of correspondence analysis showed highly significant positive correlation with nucleobases A3, C and C3 and significant negative correlation with T and T3 while F2 of correspondence analysis showed significant positive correlation with C and C3 and significant negative correlation with A and A3. From the neutrality plot, it was evident that the GC12 was influenced by mutation pressure and natural selection with a ratio of 0.10/0.90=0.11 in pisces, 0.024/0.976=0.0245 in aves and in mammals 0.215/0.785=0.273, which indicated that the role of natural selection was more than mutation pressure on structuring the bases at the first and second codon positions. Natural selection played the major role; but compositional constraint and mutation pressure also played a significant role in codon usage pattern. Analysis of codon usage pattern has contributed to the better understanding of the mechanism of distribution of codons and the evolution of MT-CYB gene. PMID:27063508

  17. Prediction of Low Vision Aid Usage.

    ERIC Educational Resources Information Center

    Eaglstein, A.; Rapaport, S.

    1991-01-01

    Use of 11 kinds of visual aids by 458 clients of an Israel low vision clinic was evaluated by age, sex, work status, participation in a rehabilitation program, academic status, number of visual aids in use, and number of diagnosed eye diseases. Usage prediction was found to be complex and highly differentiated. (Author/JDD)

  18. Predicting Student Success via Online Homework Usage

    ERIC Educational Resources Information Center

    Bowman, Charles R.; Gulacar, Ozcan; King, Daniel B.

    2014-01-01

    With the amount of data available through an online homework system about students' study habits, it stands to reason that such systems can be used to identify likely student outcomes. A study was conducted to see how student usage of an online chemistry homework system (OWL) correlated with student success in a general chemistry course.…

  19. Slang Usage of French by Young Americans.

    ERIC Educational Resources Information Center

    Ensz, Kathleen Y.

    1985-01-01

    Describes reactions of native French speakers to usage of French slang by young American students. French-speaking participants rated 30 tape-recorded slang expressions. Their reactions were evaluated in relation to the sex, profession, age, and residence of the respondents. Results show attitudes critical of the use of slang in general. (SED)

  20. Notational usage modulates attention networks in binumerates

    PubMed Central

    Koul, Atesh; Tyagi, Vaibhav; Singh, Nandini C.

    2014-01-01

    Multicultural environments require learning multiple number notations wherein some are encountered more frequently than others. This leads to differences in exposure and consequently differences in usage between notations. We find that differential notational usage imposes a significant neurocognitive load on number processing. Despite simultaneous acquisition, twenty four adult binumerates, familiar with two positional writing systems namely Hindu Nagari digits and Hindu Arabic digits, reported significantly lower preference and usage for Nagari as compared to Arabic. Twenty-four participants showed significantly increased reaction times and reduced accuracy while performing magnitude comparison tasks in Nagari with respect to Arabic. Functional magnetic resonance imaging revealed that processing Nagari elicited significantly greater activity in number processing and attention networks. A direct subtraction of networks for Nagari and Arabic notations revealed a neural circuit comprising of bilateral Intra-parietal Sulcus (IPS), Inferior and Mid Frontal Gyri, Fusiform Gyrus and the Anterior Cingulate Cortex (FDR p < 0.005). Additionally, whole brain correlation analysis showed that activity in the left inferior parietal region was modulated by task performance in Nagari. We attribute the increased activation in Nagari to increased task difficulty due to infrequent exposure and usage. Our results reiterate the role of left IPS in modulating performance in numeric tasks and highlight the role of the attention network for monitoring symbolic notation mode in binumerates. PMID:24904366

  1. Language Arts: Mechanics and Usage K-12.

    ERIC Educational Resources Information Center

    Instructional Objectives Exchange, Los Angeles, CA.

    This revised collection is presented in a new format. Each objective consists of stating the general objective, giving directions, sample items, and answers. Objectives covering a wide range of writing problems are included emphasizing the improvement of clarity in expression. The text is divided into two categories: Mechanics and Usage. There are…

  2. Statistical Measures for Usage-Based Linguistics

    ERIC Educational Resources Information Center

    Gries, Stefan Th.; Ellis, Nick C.

    2015-01-01

    The advent of usage-/exemplar-based approaches has resulted in a major change in the theoretical landscape of linguistics, but also in the range of methodologies that are brought to bear on the study of language acquisition/learning, structure, and use. In particular, methods from corpus linguistics are now frequently used to study distributional…

  3. The scope of usage-based theory.

    PubMed

    Ibbotson, Paul

    2013-01-01

    Usage-based approaches typically draw on a relatively small set of cognitive processes, such as categorization, analogy, and chunking to explain language structure and function. The goal of this paper is to first review the extent to which the "cognitive commitment" of usage-based theory has had success in explaining empirical findings across domains, including language acquisition, processing, and typology. We then look at the overall strengths and weaknesses of usage-based theory and highlight where there are significant debates. Finally, we draw special attention to a set of culturally generated structural patterns that seem to lie beyond the explanation of core usage-based cognitive processes. In this context we draw a distinction between cognition permitting language structure vs. cognition entailing language structure. As well as addressing the need for greater clarity on the mechanisms of generalizations and the fundamental units of grammar, we suggest that integrating culturally generated structures within existing cognitive models of use will generate tighter predictions about how language works. PMID:23658552

  4. Production, Usage, and Comprehension in Animal Vocalizations

    ERIC Educational Resources Information Center

    Seyfarth, Robert M.; Cheney, Dorothy L.

    2010-01-01

    In this review, we place equal emphasis on production, usage, and comprehension because these components of communication may exhibit different developmental trajectories and be affected by different neural mechanisms. In the animal kingdom generally, learned, flexible vocal production is rare, appearing in only a few orders of birds and few…

  5. Usage Patterns of Open Genomic Data

    ERIC Educational Resources Information Center

    Xia, Jingfeng; Liu, Ying

    2013-01-01

    This paper uses Genome Expression Omnibus (GEO), a data repository in biomedical sciences, to examine the usage patterns of open data repositories. It attempts to identify the degree of recognition of data reuse value and understand how e-science has impacted a large-scale scholarship. By analyzing a list of 1,211 publications that cite GEO data…

  6. CMSU Library Usage: Telephone Survey Results.

    ERIC Educational Resources Information Center

    Wales, Barbara; And Others

    The Assessment Committee of Library Services at Central Missouri State University conducted a telephone survey of 500 (41.2% completion rate) university students. The goals were to use a random sampling in order to gain more information regarding usage patterns of library services; to identify factors which inhibit patron use; and to reveal…

  7. The Scope of Usage-Based Theory

    PubMed Central

    Ibbotson, Paul

    2013-01-01

    Usage-based approaches typically draw on a relatively small set of cognitive processes, such as categorization, analogy, and chunking to explain language structure and function. The goal of this paper is to first review the extent to which the “cognitive commitment” of usage-based theory has had success in explaining empirical findings across domains, including language acquisition, processing, and typology. We then look at the overall strengths and weaknesses of usage-based theory and highlight where there are significant debates. Finally, we draw special attention to a set of culturally generated structural patterns that seem to lie beyond the explanation of core usage-based cognitive processes. In this context we draw a distinction between cognition permitting language structure vs. cognition entailing language structure. As well as addressing the need for greater clarity on the mechanisms of generalizations and the fundamental units of grammar, we suggest that integrating culturally generated structures within existing cognitive models of use will generate tighter predictions about how language works. PMID:23658552

  8. The Value of Precise Language Usage

    ERIC Educational Resources Information Center

    Petress, Ken

    2006-01-01

    Precision in language usage can be thought of as an ego boosting activity, a snobbish pastime, an arrogant trait; or it can be interpreted as an attempt to aid audiences in understanding exact meaning, an effort to reduce ambiguity, and/or as a positive role model for others in one's language community. This essay argues that the latter set of…

  9. Di-codon Usage for Gene Classification

    NASA Astrophysics Data System (ADS)

    Nguyen, Minh N.; Ma, Jianmin; Fogel, Gary B.; Rajapakse, Jagath C.

    Classification of genes into biologically related groups facilitates inference of their functions. Codon usage bias has been described previously as a potential feature for gene classification. In this paper, we demonstrate that di-codon usage can further improve classification of genes. By using both codon and di-codon features, we achieve near perfect accuracies for the classification of HLA molecules into major classes and sub-classes. The method is illustrated on 1,841 HLA sequences which are classified into two major classes, HLA-I and HLA-II. Major classes are further classified into sub-groups. A binary SVM using di-codon usage patterns achieved 99.95% accuracy in the classification of HLA genes into major HLA classes; and multi-class SVM achieved accuracy rates of 99.82% and 99.03% for sub-class classification of HLA-I and HLA-II genes, respectively. Furthermore, by combining codon and di-codon usages, the prediction accuracies reached 100%, 99.82%, and 99.84% for HLA major class classification, and for sub-class classification of HLA-I and HLA-II genes, respectively.

  10. Survey of Computer Usage in Louisiana Schools.

    ERIC Educational Resources Information Center

    Kirby, Peggy C.; And Others

    A survey of computer usage in 179 randomly selected public elementary and secondary schools in Louisiana was conducted in the spring of 1988. School principals responded to questions about school size, the socioeconomic status of the student population, the number of teachers certified in computer literacy and computer science, and the number of…

  11. Usage Patterns of an Online Search System.

    ERIC Educational Resources Information Center

    Cooper, Michael D.

    1983-01-01

    Examines usage patterns of ELHILL retrieval program of National Library of Medicine's MEDLARS system. Based on sample of 6,759 searches, the study analyzes frequency of various commands, classifies messages issued by system, and investigates searcher error rates. Suggestions for redesigning program and query language are noted. Seven references…

  12. Inverse material identification in coupled acoustic-structure interaction using a modified error in constitutive equation functional

    NASA Astrophysics Data System (ADS)

    Warner, James E.; Diaz, Manuel I.; Aquino, Wilkins; Bonnet, Marc

    2014-09-01

    This work focuses on the identification of heterogeneous linear elastic moduli in the context of frequency-domain, coupled acoustic-structure interaction (ASI), using either solid displacement or fluid pressure measurement data. The approach postulates the inverse problem as an optimization problem where the solution is obtained by minimizing a modified error in constitutive equation (MECE) functional. The latter measures the discrepancy in the constitutive equations that connect kinematically admissible strains and dynamically admissible stresses, while incorporating the measurement data as additional quadratic error terms. We demonstrate two strategies for selecting the MECE weighting coefficient to produce regularized solutions to the ill-posed identification problem: 1) the discrepancy principle of Morozov, and 2) an error-balance approach that selects the weight parameter as the minimizer of another functional involving the ECE and the data misfit. Numerical results demonstrate that the proposed methodology can successfully recover elastic parameters in 2D and 3D ASI systems from response measurements taken in either the solid or fluid subdomains. Furthermore, both regularization strategies are shown to produce accurate reconstructions when the measurement data is polluted with noise. The discrepancy principle is shown to produce nearly optimal solutions, while the error-balance approach, although not optimal, remains effective and does not need a priori information on the noise level.

  13. Inverse Material Identification in Coupled Acoustic-Structure Interaction using a Modified Error in Constitutive Equation Functional

    PubMed Central

    Warner, James E.; Diaz, Manuel I.; Aquino, Wilkins; Bonnet, Marc

    2014-01-01

    This work focuses on the identification of heterogeneous linear elastic moduli in the context of frequency-domain, coupled acoustic-structure interaction (ASI), using either solid displacement or fluid pressure measurement data. The approach postulates the inverse problem as an optimization problem where the solution is obtained by minimizing a modified error in constitutive equation (MECE) functional. The latter measures the discrepancy in the constitutive equations that connect kinematically admissible strains and dynamically admissible stresses, while incorporating the measurement data as additional quadratic error terms. We demonstrate two strategies for selecting the MECE weighting coefficient to produce regularized solutions to the ill-posed identification problem: 1) the discrepancy principle of Morozov, and 2) an error-balance approach that selects the weight parameter as the minimizer of another functional involving the ECE and the data misfit. Numerical results demonstrate that the proposed methodology can successfully recover elastic parameters in 2D and 3D ASI systems from response measurements taken in either the solid or fluid subdomains. Furthermore, both regularization strategies are shown to produce accurate reconstructions when the measurement data is polluted with noise. The discrepancy principle is shown to produce nearly optimal solutions, while the error-balance approach, although not optimal, remains effective and does not need a priori information on the noise level. PMID:25339790

  14. Photopatterning of hydrogel scaffolds coupled to filter materials using stereolithography for perfused 3D culture of hepatocytes.

    PubMed

    Neiman, Jaclyn A Shepard; Raman, Ritu; Chan, Vincent; Rhoads, Mary G; Raredon, Micha Sam B; Velazquez, Jeremy J; Dyer, Rachel L; Bashir, Rashid; Hammond, Paula T; Griffith, Linda G

    2015-04-01

    In vitro models that recapitulate the liver's structural and functional complexity could prolong hepatocellular viability and function to improve platforms for drug toxicity studies and understanding liver pathophysiology. Here, stereolithography (SLA) was employed to fabricate hydrogel scaffolds with open channels designed for post-seeding and perfused culture of primary hepatocytes that form 3D structures in a bioreactor. Photopolymerizable polyethylene glycol-based hydrogels were fabricated coupled to chemically activated, commercially available filters (polycarbonate and polyvinylidene fluoride) using a chemistry that permitted cell viability, and was robust enough to withstand perfused culture of up to 1 µL/s for at least 7 days. SLA energy dose, photoinitiator concentrations, and pretreatment conditions were screened to determine conditions that maximized cell viability and hydrogel bonding to the filter. Multiple open channel geometries were readily achieved, and included ellipses and rectangles. Rectangular open channels employed for subsequent studies had final dimensions on the order of 350 µm by 850 µm. Cell seeding densities and flow rates that promoted cell viability were determined. Perfused culture of primary hepatocytes in hydrogel scaffolds in the presence of soluble epidermal growth factor (EGF) prolonged the maintenance of albumin production throughout the 7-day culture relative to 2D controls. This technique of bonding hydrogel scaffolds can be employed to fabricate soft scaffolds for a number of bioreactor configurations and applications. PMID:25384798

  15. Selective Factors Associated with the Evolution of Codon Usage in Natural Populations of Arboviruses.

    PubMed

    Velazquez-Salinas, Lauro; Zarate, Selene; Eschbaumer, Michael; Pereira Lobo, Francisco; Gladue, Douglas P; Arzt, Jonathan; Novella, Isabel S; Rodriguez, Luis L

    2016-01-01

    Arboviruses (arthropod borne viruses) have life cycles that include both vertebrate and invertebrate hosts with substantial differences in vector and host specificity between different viruses. Most arboviruses utilize RNA for their genetic material and are completely dependent on host tRNAs for their translation, suggesting that virus codon usage could be a target for selection. In the current study we analyzed the relative synonymous codon usage (RSCU) patterns of 26 arboviruses together with 25 vectors and hosts, including 8 vertebrates and 17 invertebrates. We used hierarchical cluster analysis (HCA) and principal component analysis (PCA) to identify trends in codon usage. HCA demonstrated that the RSCU of arboviruses reflects that of their natural hosts, but not that of dead-end hosts. Of the two major components identified by PCA, the first accounted for 62.1% of the total variance, and among the 59 codons analyzed in this study, the leucine codon CTG had the highest correlation with the first principal component, however isoleucine had the highest correlation during amino acid analysis. Nucleotide and dinucleotide composition were the variables that explained most of the total codon usage variance. The results suggest that the main factors driving the evolution of codon usage in arboviruses is based on the nucleotide and dinucleotide composition present in the host. Comparing codon usage of arboviruses and potential vector hosts can help identifying potential vectors for emerging arboviruses. PMID:27455096

  16. Selective Factors Associated with the Evolution of Codon Usage in Natural Populations of Arboviruses

    PubMed Central

    Velazquez-Salinas, Lauro; Zarate, Selene; Eschbaumer, Michael; Pereira Lobo, Francisco; Gladue, Douglas P.; Arzt, Jonathan; Novella, Isabel S.; Rodriguez, Luis L.

    2016-01-01

    Arboviruses (arthropod borne viruses) have life cycles that include both vertebrate and invertebrate hosts with substantial differences in vector and host specificity between different viruses. Most arboviruses utilize RNA for their genetic material and are completely dependent on host tRNAs for their translation, suggesting that virus codon usage could be a target for selection. In the current study we analyzed the relative synonymous codon usage (RSCU) patterns of 26 arboviruses together with 25 vectors and hosts, including 8 vertebrates and 17 invertebrates. We used hierarchical cluster analysis (HCA) and principal component analysis (PCA) to identify trends in codon usage. HCA demonstrated that the RSCU of arboviruses reflects that of their natural hosts, but not that of dead-end hosts. Of the two major components identified by PCA, the first accounted for 62.1% of the total variance, and among the 59 codons analyzed in this study, the leucine codon CTG had the highest correlation with the first principal component, however isoleucine had the highest correlation during amino acid analysis. Nucleotide and dinucleotide composition were the variables that explained most of the total codon usage variance. The results suggest that the main factors driving the evolution of codon usage in arboviruses is based on the nucleotide and dinucleotide composition present in the host. Comparing codon usage of arboviruses and potential vector hosts can help identifying potential vectors for emerging arboviruses. PMID:27455096

  17. Material Studies Related to the Use of NaK Heat Exchangers Coupled to Stirling Heater Heads

    NASA Technical Reports Server (NTRS)

    Locci, Ivan E.; Bowman, Cheryl L.; Geng, Steven M.; Robbie, Malcolm G.

    2011-01-01

    NASA has been supporting design studies and technology development that could provide power to an outpost on the Moon, Mars, or an asteroid. Technology development efforts have included fabrication and evaluation of components used in a Stirling engine power conversion system. Destructive material evaluation was performed on a NaK shell heat exchanger that was developed by the NASA Glenn Research Center (GRC) and integrated with a commercial 1 kWe Stirling convertor from Sunpower Incorporated. The NaK Stirling test demonstrated Stirling convertor electrical power generation using a pumped liquid metal heat source under thermal conditions that represent the heat exchanger liquid metal loop in a Fission Power Systems (FPS) reactor. The convertors were operated for a total test time of 66 hr at a maximum temperature of 823 K. After the test was completed and NaK removed, the heat exchanger assembly was sectioned to evaluate any material interactions with the flowing liquid metal. Several dissimilar-metal braze joint options, crucial for the heat exchanger transfer path, were also investigated. A comprehensive investigation was completed and lessons learned for future heat exchanger development efforts are discussed.

  18. Ductile Tearing of Thin Aluminum Plates Under Blast Loading. Predictions with Fully Coupled Models and Biaxial Material Response Characterization

    SciTech Connect

    Corona, Edmundo; Gullerud, Arne S.; Haulenbeek, Kimberly K.; Reu, Phillip L.

    2015-06-01

    The work presented in this report concerns the response and failure of thin 2024- T3 aluminum alloy circular plates to a blast load produced by the detonation of a nearby spherical charge. The plates were fully clamped around the circumference and the explosive charge was located centrally with respect to the plate. The principal objective was to conduct a numerical model validation study by comparing the results of predictions to experimental measurements of plate deformation and failure for charges with masses in the vicinity of the threshold between no tearing and tearing of the plates. Stereo digital image correlation data was acquired for all tests to measure the deflection and strains in the plates. The size of the virtual strain gage in the measurements, however, was relatively large, so the strain measurements have to be interpreted accordingly as lower bounds of the actual strains in the plate and of the severity of the strain gradients. A fully coupled interaction model between the blast and the deflection of the structure was considered. The results of the validation exercise indicated that the model predicted the deflection of the plates reasonably accurately as well as the distribution of strain on the plate. The estimation of the threshold charge based on a critical value of equivalent plastic strain measured in a bulge test, however, was not accurate. This in spite of efforts to determine the failure strain of the aluminum sheet under biaxial stress conditions. Further work is needed to be able to predict plate tearing with some degree of confidence. Given the current technology, at least one test under the actual blast conditions where the plate tears is needed to calibrate the value of equivalent plastic strain when failure occurs in the numerical model. Once that has been determined, the question of the explosive mass value at the threshold could be addressed with more confidence.

  19. Modeling of resonant magneto-electric effect in a magnetostrictive and piezoelectric laminate composite structure coupled by a bonding material

    NASA Astrophysics Data System (ADS)

    Hasanyan, D.; Wang, Y.; Gao, J.; Li, M.; Shen, Y.; Li, J.; Viehland, D.

    2012-09-01

    The harmonic magneto-electro-elastic vibration of a thin laminated composite was considered. A theoretical model, including shear lag and vibration effects was developed for predicting the magneto-electric (ME) effect in a laminate composite consisting of magnetostrictive and piezoelectric layers. To avoid bending, we assumed that the composite was geometrically symmetric. For finite length symmetrically fabricated laminates, we derived the dynamic strain-stress field and ME coefficients, including shear lag and vibration effects for several boundary conditions. Parametric studies are presented to evaluate the influences of material properties and geometries on the strain distribution and the ME coefficient. Analytical expressions indicate that the shear lag and the vibration frequency strongly influence the strain distribution in the laminates and these effects strongly influence the ME coefficients.

  20. Coupling phase transition kinetics and hydrodynamics: Models for solid-solid and liquid-solid transformation in dynamically driven materials

    NASA Astrophysics Data System (ADS)

    Belof, Jonathan; Benedict, Lorin; Chernov, Alexander; Hall, Burl; Hamel, Sebastien; Haxhimali, Tomorr; Sadigh, Babak; Zepeda-Ruiz, Luis

    High pressure and high strain-rate experiments are opening a new frontier toward the study of material science under extreme conditions. As the energy density of experimental platforms is increased, the timescale for observation is typically decreased to the point where the time dependence of phase transitions is now a subject of direct study. We will present new phase transition kinetics models that have been developed with unique considerations that arise in shock-wave driven phase transformation, highlighting applications of the methodology to the simulation of recent experiments of iron and water. This work is performed under the auspices of the U. S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  1. Determination of ultratrace impurity elements in high purity niobium materials by on-line matrix separation and direct injection/inductively coupled plasma mass spectrometry.

    PubMed

    Kozono, Shuji; Haraguchi, Hiroki

    2007-07-31

    The determination of 52 impurity elements in niobium materials (niobium metal, niobium oxide (V), and niobium pentaethoxide) was performed by inductively coupled plasma mass spectrometry (ICP-MS) with on-line anion exchange matrix separation as well as direct nebulization. Niobium material samples were decomposed with a mixture of hydrofluoric acid and nitric acid to prepare 10% niobium solutions. In the on-line anion exchange matrix separation/ICP-MS, the niobium and hydrofluoric acid concentrations in sample solution were adjusted to 5% and ca. 8M, respectively. The solution was then injected into the carrier stream from the sample loop of injection valve to pass through an anion exchange resin column. In the anion exchange separation, niobium in the fluoro-complex form was adsorbed on the resin, while impurity elements were eluted. The eluted elements were introduced into ICP-MS for the determination of 25 impurity elements. On the other hand, 27 impurity elements could not be separated well from niobium matrix under the above anion exchange conditions, and then the sample solution with the niobium concentration of max. 0.2% containing internal standard elements was injected from the sample loop of injection valve directly to introduce into ICP-MS. As a result, 52 impurity elements in three kinds of niobium materials could be determined at the ng g(-1) level. PMID:19071834

  2. Reconfigured, close-coupled reconfigured, and Wyodak coal integrated two-stage coal liquefaction process materials from the Wilsonville facility: Chemical and toxicological evaluation

    SciTech Connect

    Wright, C.W.

    1987-03-01

    This document reports the results of the chemical analysis and toxicological testing of process materials sampled during the operation of the Advanced Coal Liquefaction Research and Development Facility (Wilsonville, AL) in the reconfigured, integrated (RITSL run No. 247), the close-coupled, reconfigured, integrated (CCRITSL run No. 249), and the Wyodak coal integrated (ITSL run No. 246) two-stage liquefaction operating modes. Chemical methods of analysis included proton nuclear magnetic resonance spectroscopy, adsorption column chromatography, high resolution gas chromatography, gas chromatography/mass spectrometry, and low-voltage probe-inlet mass spectrometry. Toxicological evaluation of the process materials included a histidine reversion assay for microbial mutagenicity, an initiation/promotion assay for tumorigenicity in mouse skin, and an aquatic toxicity assay using Daphnia magna. The results of these analyses and tests are compared to the previously reported results derived from the Illinois No. 6 coal ITSL and nonintegrated two-stage liquefaction (NTSL) process materials from the Wilsonville facility. 21 refs., 13 figs., 21 tabs.

  3. Modified mesoporous silica materials for on-line separation and preconcentration of hexavalent chromium using a microcolumn coupled with flame atomic absorption spectrometry.

    PubMed

    Wang, Zheng; Fang, Dong-Mei; Li, Qing; Zhang, Ling-Xia; Qian, Rong; Zhu, Yan; Qu, Hai-Yun; Du, Yi-Ping

    2012-05-01

    A modified SBA-15 mesoporous silica material NH(2)-SBA-15 was synthesized successfully by grafting γ-aminopropyl-triethoxysilane. The material was characterized using transmission electron microscopy (TEM) and Fourier transform infrared/Raman (FT-IR/Raman) spectroscopy, and used for the first time in a flow injection on-line solid phase extraction (SPE) coupled with flame atomic absorption spectrometry (FAAS) to detect trace Cr (VI). Effective sorption of Cr (VI) was achieved at pH 2.0 with no interference from Cr (III) and other ions and 0.5 mol L(-1) NH(3)·H(2)O solution was found optimal for the complete elution of Cr (VI). An enrichment factor of 44 and was achieved under optimized experimental conditions at a sample loading of 2.0 mL min(-1) sample loading (300 s) and an elution flow rate of 2.0 mL min(-1) (24s). The precision of the 11 replicate Cr (VI) measurements was 2.1% at the 100 μg L(-1) level with a detection limit of 0.2 μg L(-1) (3s, n=10) using the FAAS. The developed method was successfully applied to trace chromium determination in waste water. The accuracy was validated using a certified reference material of riverine water (GBW08607). PMID:22502615

  4. Multi-block analysis coupled to laser-induced breakdown spectroscopy for sorting geological materials from caves.

    PubMed

    Ammari, Faten; Bassel, Léna; Ferrier, Catherine; Lacanette, Delphine; Chapoulie, Rémy; Bousquet, Bruno

    2016-10-01

    In this study, multi-block analysis was applied for the first time to LIBS spectra provided by a portable LIBS system (IVEA Solution, France) equipped with three compact Czerny-Turner spectrometers covering the spectral ranges 200-397nm, 398-571nm and 572-1000nm. 41 geological samples taken from a laboratory-cave situated in the "Vézère valley", an area rich with prehistoric sites and decorated caves listed as a UNESCO world heritage in the south west of France, were analyzed. They were composed of limestone and clay considered as underlying supports and of two types of alterations referred as moonmilk and coralloid. Common Components and Specific Weights Analysis (CCSWA) allowed sorting moonmilk and coralloid samples. The loadings revealed higher amounts of magnesium, silicon, aluminum and strontium in coralloids and the saliences emphasized that among the three spectrometers installed in the LIBS instrument used in this work; that covering the range 572-1000nm was less contributive. This new approach for processing LIBS data not only provides good results for sorting geological materials but also clearly reveals which spectral range contains most of the information. This specific advantage of multi-block analysis could lead for some applications to simplify the design and to reduce the size of LIBS instruments. PMID:27474310

  5. Carboxylic acid-grafted mesoporous material and its high catalytic activity in one-pot three-component coupling reaction

    SciTech Connect

    Gomes, Ruth; Bhaumik, Asim; Dutta, Saikat

    2014-11-01

    A new carboxylic acid functionalized mesoporous organic polymer has been synthesized via in situ radical polymerization of divinylbenzene and acrylic acid using a mesoporous silica as a seed during the polymerization process under solvothermal conditions. The mesoporous material MPDVAA-1 has been thoroughly characterized employing powder XRD, solid state {sup 13}C cross polarization magic angle spinning-nuclear magnetic resonance, FT-IR spectroscopy, N{sub 2} sorption, HR-TEM, and NH{sub 3} temperature programmed desorption-thermal conductivity detector (TPD-TCD) analysis to understand its porosity, chemical environment, bonding, and surface properties. The mesoporous polymer was used as a catalyst for a three comp onent Biginelli condensation between various aldehydes, β-keto esters, and urea/thioureas to give 3,4-dihydropyrimidine-2(1H)-ones. The reactions were carried out under conventional heating as well as solvent-free microwave irradiation of solid components, and in both the cases, the mesoporous polymer MPDVAA-1 proved to be a powerful, robust, and reusable catalyst with high catalytic efficiency.

  6. Carboxylic acid-grafted mesoporous material and its high catalytic activity in one-pot three-component coupling reaction

    NASA Astrophysics Data System (ADS)

    Gomes, Ruth; Dutta, Saikat; Bhaumik, Asim

    2014-11-01

    A new carboxylic acid functionalized mesoporous organic polymer has been synthesized via in situ radical polymerization of divinylbenzene and acrylic acid using a mesoporous silica as a seed during the polymerization process under solvothermal conditions. The mesoporous material MPDVAA-1 has been thoroughly characterized employing powder XRD, solid state 13C cross polarization magic angle spinning-nuclear magnetic resonance, FT-IR spectroscopy, N2 sorption, HR-TEM, and NH3 temperature programmed desorption-thermal conductivity detector (TPD-TCD) analysis to understand its porosity, chemical environment, bonding, and surface properties. The mesoporous polymer was used as a catalyst for a three comp onent Biginelli condensation between various aldehydes, β-keto esters, and urea/thioureas to give 3,4-dihydropyrimidine-2(1H)-ones. The reactions were carried out under conventional heating as well as solvent-free microwave irradiation of solid components, and in both the cases, the mesoporous polymer MPDVAA-1 proved to be a powerful, robust, and reusable catalyst with high catalytic efficiency.

  7. Implanted, inductively-coupled, radiofrequency coils fabricated on flexible polymeric material: Application to in vivo rat brain MRI at 7 T

    NASA Astrophysics Data System (ADS)

    Ginefri, J.-C.; Rubin, A.; Tatoulian, M.; Woytasik, M.; Boumezbeur, F.; Djemaï, B.; Poirier-Quinot, M.; Lethimonnier, F.; Darrasse, L.; Dufour-Gergam, E.

    2012-11-01

    Combined with high-field MRI scanners, small implanted coils allow for high resolution imaging with locally improved SNR, as compared to external coils. Small flexible implantable coils dedicated to in vivo MRI of the rat brain at 7 T were developed. Based on the Multi-turn Transmission Line Resonator design, they were fabricated with a Teflon substrate using copper micromolding process and a specific metal-polymer adhesion treatment. The implanted coils were made biocompatible by PolyDimethylSiloxane (PDMS) encapsulation. The use of low loss tangent material achieves low dielectric losses within the substrate and the use of the PDMS layer reduces the parasitic coupling with the surrounding media. An implanted coil was implemented in a 7 T MRI system using inductive coupling and a dedicated external pick-up coil for signal transmission. In vivo images of the rat brain acquired with in plane resolution of (150 μm)2 thanks to the implanted coil revealed high SNR near the coil, allowing for the visualization of fine cerebral structures.

  8. Comparative investigation of the various determinants that influence the codon and amino acid usage patterns in the genus Bifidobacterium.

    PubMed

    Roy, Ayan; Mukhopadhyay, Subhasish; Sarkar, Indrani; Sen, Arnab

    2015-06-01

    Various strains of the genus Bifidobacterium are crucial members of the human, animal and insect gut, associated with beneficial probiotic activities. An extensive analysis on codon and amino acid usage of the GC rich genus Bifidobacterium has been executed in the present study. Multivariate statistical analysis revealed a coupled effect of GC compositional constraint and natural selection for translational efficiency to be operative in producing the observed codon usage variations. Gene expression level was inferred to be the most crucial factor governing the codon usage patterns. Amino acid usage was found to be influenced significantly by hydrophobic and aromatic character of the encoded proteins. Gene expressivity and protein energetic cost also had considerable impact on the differential mode of amino acid usage. The genus was found to strictly obey the cost-minimization hypothesis as was reflected from the amino acid usage patterns of the potential highly expressed gene products. Evolutionary analysis revealed that the highly expressed genes were candidates to extreme evolutionary selection pressure and indicated a high degree of conservation at the proteomic level. Interestingly, the complimentary strands of replication appeared to evolve under similar evolutionary constraints which might be addressed as a consequence of absence of replicational selection and lack of strand-specific asymmetry among the members of the genus. Thus, the present endeavor confers considerable know-how pertaining to the codon and amino acid usage intricacies in Bifidobacterium and might prove handy for further scientific investigations associated with the concerned domain. PMID:25842224

  9. Quantification of modifiers in advanced materials based on zinc oxide by total reflection X-ray fluorescence and inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Filatova, Daria G.; Alov, Nikolai V.; Vorobyeva, Natalia A.; Rumyantseva, Marina N.; Sharanov, Pavel Yu.; Seregina, Irina F.; Gaskov, Alexander M.

    2016-04-01

    A novel approach to quantification of Ga and Zn modifiers in advanced materials based on zinc oxide is presented. The approach includes a combination of total reflection X-ray fluorescence (TXRF) and inductively coupled plasma mass spectrometry (ICP-MS) for determination and validation of the results. It is suggested to use aqueous standards for the direct determination of elements in powder samples by TXRF with a relative standard deviation no more than sr = 0.11. The accuracy of these results was proved by ICP-MS after the sample decomposition, sr(In) = 0.05, sr(Ga) = 0.06 and sr(Zn) = 0.06. It was established that there is a possibility to determine indium above 300 ppb on the background of K-M3 line of argon.

  10. Ultra-trace determination of iodine in sediments and biological material using UV photochemical generation-inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Grinberg, Patricia; Sturgeon, Ralph E.

    2009-03-01

    Several sample preparation techniques have been evaluated for the determination of iodine using UV-photochemical generation-quadrupole inductively coupled plasma mass spectrometry. Thermal decomposition of samples at 1000 °C followed by capture of the liberated iodine in dilute acetic acid permitted subsequent UV-photochemical generation of a volatile iodine species that serves to enhance sensitivity 25-fold over conventional solution nebulization, delivering reagent blank detection limits of 8.75 pg g -1 127I and 0.075 pg g -1 129I for solid samples (400 mg test mass). The methodology was validated through determination of total iodine in several Standard Reference Materials, including NIST 1572 Citrus leaves, NIST 1549 Non-fat milk powder, NIST 1566a Oyster tissue and NIST 2709 San Joaquin Soil. Liberation of iodine from samples and its collection as well as photochemical generation were quantitative, permitting calibration to be achieved using standards prepared in dilute acetic acid.

  11. Evaluation of material parameters using contra-directional single incident beam two-beam coupling in Fe:LiNbO3

    NASA Astrophysics Data System (ADS)

    Saleh, M. A.; Evans, D. R.; Allen, A. S.; Bunning, T. J.; Guha, S.

    2002-03-01

    By fitting the experimental results to a theoretical analysis of two-beam coupling including diffraction effects [1], the photorefractive gain as well the dark current irradiance has been evaluated. Crystals with a transparent conductive coating were used to reduce grating writing instabilities; instabilities as well as multiple reflection effects were also eliminated by AR (anti-reflection) coating the crystal surfaces [2]. [1] G. Cook, D. C. Jones, C. J. Finnan, L. L. Taylor, T. W. Vere, and J. P. Duignan, Materials Research Society Symposium Proceedings 597 (2000) 263-274. [2] D. R. Evans, S. A. Basun, M. A. Saleh, T. P. Pottenger, G. Cook, T. J. Bunning, and S. Guha, "Elimination of Photorefractive Grating Writing Instabilities in Iron-doped Lithium Niobate," Submitted to IEEE J. Quantum Electronics. Dec. 2001.

  12. Summary usage statistics of the Helioviewer Project

    NASA Astrophysics Data System (ADS)

    Ireland, Jack; Stys, J. E.

    2013-07-01

    The Helioviewer Project enables visual exploration of the Sun and the inner heliosphere for everyone, everywhere via intuitive interfaces and novel technology. Images from the SDO, STEREO, SOHO, PROBA2 and Yohkoh missions are currently available. Users of the Helioviewer Project have made over one million movies and over two million screenshots since detailed (and anonymous) logging of Helioviewer Project usage was implemented in February 2011. These usage logs are analyzed to give a detailed breakdown on user interaction with solar and heliospheric data via Helioviewer Project clients and services. We present summary statistics on how our users are using our clients and services, which data they are interested in, and how they choose to interact with different data sources.

  13. Historical review of medicinal plants’ usage

    PubMed Central

    Petrovska, Biljana Bauer

    2012-01-01

    Healing with medicinal plants is as old as mankind itself. The connection between man and his search for drugs in nature dates from the far past, of which there is ample evidence from various sources: written documents, preserved monuments, and even original plant medicines. Awareness of medicinal plants usage is a result of the many years of struggles against illnesses due to which man learned to pursue drugs in barks, seeds, fruit bodies, and other parts of the plants. Contemporary science has acknowledged their active action, and it has included in modern pharmacotherapy a range of drugs of plant origin, known by ancient civilizations and used throughout the millennia. The knowledge of the development of ideas related to the usage of medicinal plants as well as the evolution of awareness has increased the ability of pharmacists and physicians to respond to the challenges that have emerged with the spreading of professional services in facilitation of man's life. PMID:22654398

  14. Historical review of medicinal plants' usage.

    PubMed

    Petrovska, Biljana Bauer

    2012-01-01

    Healing with medicinal plants is as old as mankind itself. The connection between man and his search for drugs in nature dates from the far past, of which there is ample evidence from various sources: written documents, preserved monuments, and even original plant medicines. Awareness of medicinal plants usage is a result of the many years of struggles against illnesses due to which man learned to pursue drugs in barks, seeds, fruit bodies, and other parts of the plants. Contemporary science has acknowledged their active action, and it has included in modern pharmacotherapy a range of drugs of plant origin, known by ancient civilizations and used throughout the millennia. The knowledge of the development of ideas related to the usage of medicinal plants as well as the evolution of awareness has increased the ability of pharmacists and physicians to respond to the challenges that have emerged with the spreading of professional services in facilitation of man's life. PMID:22654398

  15. Determination of boron in high-purity tantalum materials by on-line matrix separation/inductively coupled plasma mass spectrometry.

    PubMed

    Kozono, Shuji; Takahashi, Shigeto; Haraguchi, Hiroki

    2002-07-01

    A method for the determination of ultratrace amounts of boron in high-purity tantalum materials [tantalum metal, tantalum(v) oxide, tantalum pentachloride and tantalum pentaethoxide] is described. On-line anion-exchange matrix separation combined with inductively coupled plasma mass spectrometry (ICP-MS) was employed for the determination of boron at the ng g(-1) level. Tantalum materials were dissolved using HF and/or HNO3 prior to analysis. The loss of boron in the sample preparation procedure was examined as the recovery of boron by adding a definite amount of boron to each tantalum material sample before decomposition, and it was almost negligible. In an anion-exchange method using 0.1 M HF carrier solution, tantalum and boron in the sample solution were first adsorbed on a strongly basic anion-exchange resin. Next, boron was eluted from the resin with 5 M HCl, whereas tantalum was retained strongly adsorbed. The eluted boron was introduced directly into the ICP-MS system for quantitative analysis at m/z 10 and 11. Because of the long elution time of boron, the transient signal was integrated in the time range 70-300 s on the chromatogram. Although the elution of boron in the time range was ca. 40% of total boron in the sample solution injected, the determination limits (10sigma) obtained by the present method were 30, 25, 15 and 13 ng g(-1) for tantalum metal, tantalum(v) oxide, tantalum pentachloride and tantalum pentaethoxide, respectively. The method was applied to the determination of boron in commercially available high-purity tantalum materials and it was found that the concentrations of boron were in the ng g(-1)-microg g(-1) range. PMID:12173652

  16. Characterizing food usage by demographic variables.

    PubMed

    Cronin, F J; Krebs-Smith, S M; Wyse, B W; Light, L

    1982-12-01

    On the basis of an analysis of three-day food records, food comsumption by major segments of the U.S. population was examined for 65 food groups and subgroups. This study indicates that demographic factors, particularly age, race, and region, can affect both the percentage of persons using certain foods and the mean frequency of their use. Both the similarities and the differences on these parameters are of interest when food usage is examined by demographic variables. PMID:7142608

  17. Space Shuttle Usage of z/OS

    NASA Technical Reports Server (NTRS)

    Green, Jan

    2009-01-01

    This viewgraph presentation gives a detailed description of the avionics associated with the Space Shuttle's data processing system and its usage of z/OS. The contents include: 1) Mission, Products, and Customers; 2) Facility Overview; 3) Shuttle Data Processing System; 4) Languages and Compilers; 5) Application Tools; 6) Shuttle Flight Software Simulator; 7) Software Development and Build Tools; and 8) Fun Facts and Acronyms.

  18. Nurses' MEDLINE usage and research utilization.

    PubMed

    Prin, P L; Mills, M E

    1997-01-01

    This exploratory study in the field of nursing informatics examined the usage of information technology, namely on-line access to MEDLINE in clinical setting, by a convenience sample of 121 nurses from a large university hospital. A descriptive correlational design was used. Guided by the conceptual frameword of Nurse-Computer Interaction and based on variables set forth in the Theory of Reasoned Action, the study tested hypotheses regarding attitudinal and normative influences on reported use of on-line bibliographic retrieval systems. It was also hypothesized that using MEDLINE coild increase and improve nurses' adoption of nursing research findings. Multiple regression analyses were conducted on nurses' responses to survey questions to test hypotheses-that those who register more favorable attitudes towards nursing research would have a higher reported use of the MEDLINE system. Findings were significant and supported the hypothesis that nurses' attitudes towards research influenced MEDLINE usage. Findings also indicated that MEDLINE usage was significantly related to nurses' research utilization. PMID:10175440

  19. Stachytarpheta jamaicensis (L.) Vahl: From Traditional Usage to Pharmacological Evidence

    PubMed Central

    Liew, Pearl Majorie; Yong, Yoke Keong

    2016-01-01

    Introduction. Stachytarpheta jamaicensis (L.) Vahl belongs to the family of Verbenaceae and is commonly known as Gervao, Brazilian tea, verbena cimarrona, rooter comb, or blue porter weed. It is one of the important plants with high medicinal and nutraceutical benefits. S. jamaicensis contains various medicinal properties in traditional and folk medicinal systems, with cures for several diseases. Objective. The objective of this review paper is to collect information concerning the morphology, distribution, traditional usage, phytochemical compositions, biological activities, and safety data of S. jamaicensis. Materials and Methods. The information was obtained from literature search through electronic databases such as PubMed and Google Scholar on S. jamaicensis. Results and Conclusion. The high medicinal properties of this plant, for instance, antimicrobial and antifungal effect as the main activities, but verbascoside as the main active chemical component, make it a valuable source of the medicinal compound. This review paper summarizes all information concerning the morphology, distribution, traditional usage, phytochemical compositions, pharmacological activities, and toxicological studies of S. jamaicensis. PMID:26925152

  20. Stachytarpheta jamaicensis (L.) Vahl: From Traditional Usage to Pharmacological Evidence.

    PubMed

    Liew, Pearl Majorie; Yong, Yoke Keong

    2016-01-01

    Introduction. Stachytarpheta jamaicensis (L.) Vahl belongs to the family of Verbenaceae and is commonly known as Gervao, Brazilian tea, verbena cimarrona, rooter comb, or blue porter weed. It is one of the important plants with high medicinal and nutraceutical benefits. S. jamaicensis contains various medicinal properties in traditional and folk medicinal systems, with cures for several diseases. Objective. The objective of this review paper is to collect information concerning the morphology, distribution, traditional usage, phytochemical compositions, biological activities, and safety data of S. jamaicensis. Materials and Methods. The information was obtained from literature search through electronic databases such as PubMed and Google Scholar on S. jamaicensis. Results and Conclusion. The high medicinal properties of this plant, for instance, antimicrobial and antifungal effect as the main activities, but verbascoside as the main active chemical component, make it a valuable source of the medicinal compound. This review paper summarizes all information concerning the morphology, distribution, traditional usage, phytochemical compositions, pharmacological activities, and toxicological studies of S. jamaicensis. PMID:26925152

  1. Materials

    NASA Technical Reports Server (NTRS)

    Glaessgen, Edward H.; Schoeppner, Gregory A.

    2006-01-01

    NASA Langley Research Center has successfully developed an electron beam freeform fabrication (EBF3) process, a rapid metal deposition process that works efficiently with a variety of weldable alloys. The EBF3 process can be used to build a complex, unitized part in a layer-additive fashion, although the more immediate payoff is for use as a manufacturing process for adding details to components fabricated from simplified castings and forgings or plate products. The EBF3 process produces structural metallic parts with strengths comparable to that of wrought product forms and has been demonstrated on aluminum, titanium, and nickel-based alloys to date. The EBF3 process introduces metal wire feedstock into a molten pool that is created and sustained using a focused electron beam in a vacuum environment. Operation in a vacuum ensures a clean process environment and eliminates the need for a consumable shield gas. Advanced metal manufacturing methods such as EBF3 are being explored for fabrication and repair of aerospace structures, offering potential for improvements in cost, weight, and performance to enhance mission success for aircraft, launch vehicles, and spacecraft. Near-term applications of the EBF3 process are most likely to be implemented for cost reduction and lead time reduction through addition of details onto simplified preforms (casting or forging). This is particularly attractive for components with protruding details that would require a significantly large volume of material to be machined away from an oversized forging, offering significant reductions to the buy-to-fly ratio. Future far-term applications promise improved structural efficiency through reduced weight and improved performance by exploiting the layer-additive nature of the EBF3 process to fabricate tailored unitized structures with functionally graded microstructures and compositions.

  2. 50 CFR 600.910 - Definitions and word usage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Definitions and word usage. 600.910..., Consultation, and Recommendations § 600.910 Definitions and word usage. (a) Definitions. In addition to the... undertaken by a state agency. (b) Word usage. The terms “must”, “shall”, “should”, “may”, “may not”,...

  3. A Structural Equation Model for ICT Usage in Higher Education

    ERIC Educational Resources Information Center

    Usluel, Yasemin Kocak; Askar, Petek; Bas, Turgay

    2008-01-01

    This study focuses on Information and Communication Technologies (ICT) usage, which is the indicator of diffusion. A model composed of the variables which can explain ICT usage in Turkish higher education is established and tested within the study. The two dimensions of ICT usage are considered: instructional and managerial. The data collected…

  4. 50 CFR 600.910 - Definitions and word usage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Definitions and word usage. 600.910..., Consultation, and Recommendations § 600.910 Definitions and word usage. (a) Definitions. In addition to the... undertaken by a state agency. (b) Word usage. The terms “must”, “shall”, “should”, “may”, “may not”,...

  5. 50 CFR 600.910 - Definitions and word usage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Definitions and word usage. 600.910..., Consultation, and Recommendations § 600.910 Definitions and word usage. (a) Definitions. In addition to the... undertaken by a state agency. (b) Word usage. The terms “must”, “shall”, “should”, “may”, “may not”,...

  6. Effects of magnetic flux density and substrate bias voltage on Ni films prepared on a flexible substrate material using unbalanced magnetron sputtering assisted by inductively coupled plasma

    SciTech Connect

    Koda, Tatsunori; Toyota, Hiroshi

    2014-03-15

    The authors fabricated Ni films on a flexible substrate material using unbalanced magnetron sputtering assisted by inductively coupled plasma. The effects of magnetic flux density B{sub C} and substrate DC bias voltage V{sub S} on the Ni film structures were investigated. For V{sub S} = −40 V, the average surface grain size D{sub G} measured by atomic force microscopy for B{sub C} = 0, 3, and 5 mT was 88.2, 95.4, and 104.4 nm, respectively. In addition, D{sub G} increased with V{sub S}. From x-ray diffraction measurements, the (111) and (200) peaks were clearly visible for the fabricated Ni films. The ratio of the integrated intensities of I(111)/I(200) increased with V{sub S}. For V{sub S} = −40 V and B{sub C} = 3 mT, a film resistivity ρ of 8.96 × 10{sup −6} Ω cm was observed, which is close to the Ni bulk value of 6.84 × 10{sup −6} Ω cm. From these results, the authors determined that the structure of the fabricated Ni films on the flexible substrate material was affected by the values of B{sub C} and V{sub S}.

  7. Effective spin Hall properties of a mixture of materials with and without spin-orbit coupling: Tailoring the effective spin diffusion length

    NASA Astrophysics Data System (ADS)

    Yue, Z.; Prestgard, M. C.; Tiwari, A.; Raikh, M. E.

    2016-01-01

    We study theoretically the effective spin Hall properties of a composite consisting of two materials with and without spin-orbit (SO) coupling. In particular, we assume that SO material represents a system of grains in a matrix with no SO. We calculate the effective spin Hall angle and the effective spin diffusion length of the mixture. Our main qualitative finding is that, when the bare spin diffusion length is much smaller than the radius of the grain, the effective spin diffusion length is strongly enhanced, well beyond the "geometrical" factor. The physical origin of this additional enhancement is that, with small diffusion length, the spin current mostly flows around the grain without suffering much loss. We also demonstrate that the voltage, created by a spin current, is sensitive to a very weak magnetic field directed along the spin current, and even reverses sign in a certain domain of fields. The origin of this sensitivity is that the spin precession, caused by magnetic field, takes place outside the grains where SO is absent.

  8. Earth Abundant Iron-Rich N-Doped Graphene Based Spacer and Cavity Materials for Surface Plasmon-Coupled Emission Enhancements.

    PubMed

    Srinivasan, Venkatesh; Vernekar, Dnyanesh; Jaiswal, Garima; Jagadeesan, Dinesh; Ramamurthy, Sai Sathish

    2016-05-18

    We demonstrate for the first time the use of Fe-based nanoparticles on N-doped graphene as spacer and cavity materials and study their plasmonic effect on the spontaneous emission of a radiating dipole. Fe-C-MF was produced by pyrolizing FeOOH and melamine formaldehyde precursor on graphene, while Fe-C-PH was produced by pyrolizing the Fe-phenanthroline complex on graphene. The use of the Fe-C-MF composite consisting of Fe-rich crystalline phases supported on N-doped graphene presented a spacer material with 116-fold fluorescence enhancements. On the other hand, the Fe-C-PH/Ag based cavity resulted in an 82-fold enhancement in Surface Plasmon-Coupled Emission (SPCE), with high directionality and polarization of Rhodamine 6G (Rh6G) emission owing to Casimir and Purcell effects. The use of a mobile phone as a cost-effective fluorescence detection device in the present work opens up a flexible perspective for the study of different nanomaterials as tunable substrates in cavity mode and spacer applications. PMID:27128348

  9. 3-D Modeling of Directional Solidification of a Non-Dilute Alloy with Temperature and Concentration Fields Coupling via Materials Properties Dependence and via Double Diffusive Convection

    NASA Technical Reports Server (NTRS)

    Bune, Andris V.; Gillies, Donald C.; Lehoczky, Sandor L.

    1998-01-01

    Numerical simulation of the HgCdTe growth by the vertical Bridgman method was performed using FIDAP finite element code. Double-diffusive melt convection is analyzed, as the primary factor at controls inhomogeneity of the solidified material. Temperature and concentration fields in the model are also coupled via material properties, such as thermal and solutal expansion coefficients with the dependence on both temperature and concentration, and melting temperature evaluation from pseudobinary CdTe-HgTe phase diagram. Experimental measurements were used to obtain temperature boundary conditions. Parametric study of the melt convection dependence on the gravity conditions was undertaken. It was found, that the maximum convection velocity in the melt can be reduced under certain conditions. Optimal conditions to obtain a near flat solidified interface are discussed. The predicted interface shape is in agreement with one obtained experimentally by quenching. The results of 3-D calculations are compared with previous 2- D findings. A video film featuring 3-D melt convection will be presented.

  10. Carbon nanotubes as novel spacer materials on silver thin-films for generating superior fluorescence enhancements via surface plasmon coupled emission

    NASA Astrophysics Data System (ADS)

    Mulpur, Pradyumna; Podila, Ramakrishna; Rao, Apparao M.; Kamisetti, Venkataramaniah

    2016-06-01

    In this study, we report the first time implementation of single/multi-walled carbon nanotubes, as novel spacer materials, on a silver (Ag) thin-film based surface plasmon coupled emission (SPCE) platform. The engineered Ag-CNT SPCE substrates enabled the realization of up to ∼10-fold enhancement in fluorescence signal intensity, of the rhodamine b dye. This study addresses the issue that, while many of the biochemical sensing strategies are based on fluorescence, they are all fundamentally limited by the isotropic nature of the phenomenon that results in low signal collection efficiency (<1%). Pursuant to the aim of realizing superior levels of signal sensitivity, we previously reported graphene and C60 as novel spacer materials, and similarly project CNTs in this study as ‘active’ contributors for the amplification of fluorescence signals on the SPCE platform that generates highly directional emission, with very high signal to noise ratios and >50% signal collection efficiency. Considering the easy functionalization of these carbon nano-allotropes, and their high sensitivity; the economical Ag-CNT SPCE platforms can be effectively extended towards sensing applications.

  11. Adolescents’ Attitudes toward Anti-marijuana Ads, Usage Intentions, and Actual Marijuana Usage

    PubMed Central

    Alvaro, Eusebio M.; Crano, William D.; Siegel, Jason T.; Hohman, Zachary; Johnson, Ian; Nakawaki, Brandon

    2015-01-01

    The association of adolescents’ appraisals of the anti-marijuana television ads used in the National Youth Anti-drug Media Campaign with future marijuana use was investigated. The 12 to 18 year old respondents (N = 2993) were first classified as users, resolute nonusers, or vulnerable nonusers (Crano, Siegel, Alvaro, Lac, & Hemovich, 2008). Usage status and the covariates of gender, age, and attitudes toward marijuana were used to predict attitudes toward the ads (Aad) in the first phase of a multi-level linear analysis. All covariates were significantly associated with Aad, as was usage status: resolute nonusers evaluated the ads significantly more positively than vulnerable nonusers and users (all p < .001), who did not differ. In the second phase, the covariates along with Aad and respondents’ usage status predicted intentions and actual usage one year after initial measurement. The lagged analysis disclosed negative associations between Aad and usage intentions, and between Aad and actual marijuana use (both p < .05); however, this association held only for users (p < .01), not vulnerable or resolute nonusers. Users reporting more positive attitudes towards the ads were less likely to report intention to use marijuana and to continue marijuana use at 1-year follow-up. These findings may inform designers of persuasion-based prevention campaigns, guiding pre-implementation efforts in the design of ads that targeted groups find appealing and thus, influential. PMID:23528197

  12. Empirically testing some factors affecting HMS usage.

    PubMed

    Caccia-Bava, Maria do Carmo; Guimaraes, Valerie C K; Guimaraes, Tor

    2016-07-11

    Purpose - Without use the expected benefits from healthcare management systems (HMS) cannot be derived. Thus, while use alone may not guarantee success, one can safely assume that the more use the better. HMS has been instrumental in facilitating care providers' work. However, many hospitals have encountered usage problems and some user-related factors have been recognized in the literature as potentially important to make HMS more successful. The purpose of this paper is to test the importance of the factors proposed in the literature as important determinants of HMS usage measured by the number of hours used and the frequency of use. Design/methodology/approach - Several user-related variables such as user participation, user expertise, and user training previously studied separately by different authors are brought together into an integrated model to be tested empirically. Data from 213 nurses using their hospital HMS have been used to test proposed relationships between the independent variables and HMS usage results. Findings - The results confirm the importance of these factors and provide the basis for managerial recommendations. Hospital managers can use the resources validated by this study to improve their own operations and improve the likelihood of success implementing HMS. Future research projects may identify other possible factors important for HMS implementation success to improve the model proposed here. Originality/value - HMS is a very widely used and an important system for hospitals, but has been neglected in research. This is one of the first rigorous studies of HMS, and the results provide new practical insights for hospital administrators. PMID:27298061

  13. Tetranucleotide usage highlights genomic heterogeneity among mycobacteriophages

    PubMed Central

    Siranosian, Benjamin; Perera, Sudheesha; Williams, Edward; Ye, Chen; de Graffenried, Christopher; Shank, Peter

    2015-01-01

    Background The genomic sequences of mycobacteriophages, phages infecting mycobacterial hosts, are diverse and mosaic. Mycobacteriophages often share little nucleotide similarity, but most of them have been grouped into lettered clusters and further into subclusters. Traditionally, mycobacteriophage genomes are analyzed based on sequence alignment or knowledge of gene content. However, these approaches are computationally expensive and can be ineffective for significantly diverged sequences. As an alternative to alignment-based genome analysis, we evaluated tetranucleotide usage in mycobacteriophage genomes. These methods make it easier to characterize features of the mycobacteriophage population at many scales. Description We computed tetranucleotide usage deviation (TUD), the ratio of observed counts of 4-mers in a genome to the expected count under a null model. TUD values are comparable between members of a phage subcluster and distinct between subclusters. With few exceptions, neighbor joining phylogenetic trees and hierarchical clustering dendrograms constructed using TUD values place phages in a monophyletic clade with members of the same subcluster. Regions in a genome with exceptional TUD values can point to interesting features of genomic architecture. Finally, we found that subcluster B3 mycobacteriophages contain significantly overrepresented 4-mers and 6-mers that are atypical of phage genomes. Conclusions Statistics based on tetranucleotide usage support established clustering of mycobacteriophages and can uncover interesting relationships within and between sequenced phage genomes. These methods are efficient to compute and do not require sequence alignment or knowledge of gene content. The code to download mycobacteriophage genome sequences and reproduce our analysis is freely available at https://github.com/bsiranosian/tango_final. PMID:27134721

  14. Quantum Dots — Characterization, Preparation and Usage in Biological Systems

    PubMed Central

    Drbohlavova, Jana; Adam, Vojtech; Kizek, Rene; Hubalek, Jaromir

    2009-01-01

    The use of fluorescent nanoparticles as probes for bioanalytical applications is a highly promising technique because fluorescence-based techniques are very sensitive. Quantum dots (QDs) seem to show the greatest promise as labels for tagging and imaging in biological systems owing to their impressive photostability, which allow long-term observations of biomolecules. The usage of QDs in practical applications has started only recently, therefore, the research on QDs is extremely important in order to provide safe and effective biosensing materials for medicine. This review reports on the recent methods for the preparation of quantum dots, their physical and chemical properties, surface modification as well as on some interesting examples of their experimental use. PMID:19333427

  15. An assessment of worldwide supercomputer usage

    SciTech Connect

    Wasserman, H.J.; Simmons, M.L.; Hayes, A.H.

    1995-01-01

    This report provides a comparative study of advanced supercomputing usage in Japan and the United States as of Spring 1994. It is based on the findings of a group of US scientists whose careers have centered on programming, evaluating, and designing high-performance supercomputers for over ten years. The report is a follow-on to an assessment of supercomputing technology in Europe and Japan that was published in 1993. Whereas the previous study focused on supercomputer manufacturing capabilities, the primary focus of the current work was to compare where and how supercomputers are used. Research for this report was conducted through both literature studies and field research in Japan.

  16. Quantitative analysis of trace elements in environmental powders with laser ablation inductively coupled mass spectrometry using non-sample-corresponding reference materials for signal evaluation

    NASA Astrophysics Data System (ADS)

    Bauer, Gerald; Limbeck, Andreas

    2015-11-01

    Laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) is an attractive alternative to traditional procedures for the analysis of environmental samples (i.e., conventional liquid measurement after sample digestion). However, for accurate quantification, certified reference materials (CRM) are necessary which match the composition of the sample and include all elements of interest at the required concentration levels. The limited availability of appropriate CRMs hampers therefore substantial application. In this work, an LA-ICP-MS procedure allowing for accurate determination of trace element contents in powdered environmental samples is presented. For LA-ICP-MS analysis, the samples are mixed with an internal standard (silver oxide) and a binder (sodium tetra borate) and subsequently pressed to pellets. Quantification is accomplished using a calibration function determined using CRMs with varying matrix composition and analyte content, pre-treated and measured in the same way as the samples. With this approach, matrix-induced ablation differences resulting from varying physical/chemical properties of the individual CRMs could be compensated. Furthermore, ICP-related matrix-effects could be minimized using collision/reaction cell technology. Applicability of the procedure has been demonstrated by assessment of Cd, Cu, Ni, and Zn in four different environmental CRMs (NIST SRM1648a (urban particulate matter), NIST SRM2709 (San Joaquin Soil), BCR144 (sewage sludge), and BCR723 (road dust)). Signal evaluation was performed by alternative use of three CRMs for calculation of the calibration function whereas the remaining fourth CRM acted as unknown sample, resulting in a good agreement between measured and certified values for all elements and reference materials.

  17. Usage analysis of user files in UNIX

    NASA Technical Reports Server (NTRS)

    Devarakonda, Murthy V.; Iyer, Ravishankar K.

    1987-01-01

    Presented is a user-oriented analysis of short term file usage in a 4.2 BSD UNIX environment. The key aspect of this analysis is a characterization of users and files, which is a departure from the traditional approach of analyzing file references. Two characterization measures are employed: accesses-per-byte (combining fraction of a file referenced and number of references) and file size. This new approach is shown to distinguish differences in files as well as users, which cam be used in efficient file system design, and in creating realistic test workloads for simulations. A multi-stage gamma distribution is shown to closely model the file usage measures. Even though overall file sharing is small, some files belonging to a bulletin board system are accessed by many users, simultaneously and otherwise. Over 50% of users referenced files owned by other users, and over 80% of all files were involved in such references. Based on the differences in files and users, suggestions to improve the system performance were also made.

  18. Better Living Through Metadata: Examining Archive Usage

    NASA Astrophysics Data System (ADS)

    Becker, G.; Winkelman, S.; Rots, A.

    2013-10-01

    The primary purpose of an observatory's archive is to provide access to the data through various interfaces. User interactions with the archive are recorded in server logs, which can be used to answer basic questions like: Who has downloaded dataset X? When did she do this? Which tools did she use? The answers to questions like these fill in patterns of data access (e.g., how many times dataset X has been downloaded in the past three years). Analysis of server logs provides metrics of archive usage and provides feedback on interface use which can be used to guide future interface development. The Chandra X-ray Observatory is fortunate in that a database to track data access and downloads has been continuously recording such transactions for years; however, it is overdue for an update. We will detail changes we hope to effect and the differences the changes may make to our usage metadata picture. We plan to gather more information about the geographic location of users without compromising privacy; create improved archive statistics; and track and assess the impact of web “crawlers” and other scripted access methods on the archive. With the improvements to our download tracking we hope to gain a better understanding of the dissemination of Chandra's data; how effectively it is being done; and perhaps discover ideas for new services.

  19. Problematic Internet Usage and Immune Function.

    PubMed

    Reed, Phil; Vile, Rebecca; Osborne, Lisa A; Romano, Michela; Truzoli, Roberto

    2015-01-01

    Problematic internet use has been associated with a variety of psychological comorbidities, but it relationship with physical illness has not received the same degree of investigation. The current study surveyed 505 participants online, and asked about their levels of problematic internet usage (Internet Addiction Test), depression and anxiety (Hospital Anxiety and Depression Scales), social isolation (UCLA Loneliness Questionnaire), sleep problems (Pittsburgh Sleep Quality Index), and their current health - General Health Questionnaire (GHQ-28), and the Immune Function Questionnaire. The results demonstrated that around 30% of the sample displayed mild or worse levels of internet addiction, as measured by the IAT. Although there were differences in the purposes for which males and females used the internet, there were no differences in terms of levels of problematic usage between genders. The internet problems were strongly related to all of the other psychological variables such as depression, anxiety, social-isolation, and sleep problems. Internet addiction was also associated with reduced self-reported immune function, but not with the measure of general health (GHQ-28). This relationship between problematic internet use and reduced immune function was found to be independent of the impact of the co-morbidities. It is suggested that the negative relationship between level of problematic internet use and immune function may be mediated by levels of stress produced by such internet use, and subsequent sympathetic nervous activity, which related to immune-supressants, such as cortisol. PMID:26244339

  20. Isolation usage in a pediatric hospital.

    PubMed

    Kim, M H; Mindorff, C; Patrick, M L; Gold, R; Ford-Jones, E L

    1987-05-01

    In a prospective 12-month study at a university-affiliated pediatric hospital, isolation usage was quantitated by ward/service, season, isolation category and type of infection (community-acquired vs nosocomial). Such information may be helpful in designing hospitals, recognizing time utilization of the pediatric infection control nurse, and defining educational and isolation needs. Hospitals with multiple bed rooms and inadequate numbers of single rooms may be unable to meet current federal isolation guidelines. The mean number of isolation days was 153 per 1000 patient days or 15.3% of bed days used. This ranged from 18.5% on the infant/toddler/preschool medical ward to 2.8% on child/teenage orthopedic surgery. Isolation requirements vary seasonally and rose to 32% in winter on one ward. Proportional frequencies of isolation category included enteric--29%, protective--28%, strict--16%, barrier (contact)--10%, multiply resistant organism (MRO)--8%, wound--5%, pregnant women (careful handwashing)--3%, blood and body fluid precautions--1%. Isolation of patients with and contacts of nosocomial infections account for 32% of isolation usage. During one third of the 365-day year, the hospital is unable to provide adequate numbers of single rooms for one to 20 patients. PMID:3647940

  1. Problematic Internet Usage and Immune Function

    PubMed Central

    Reed, Phil; Vile, Rebecca; Osborne, Lisa A.; Romano, Michela; Truzoli, Roberto

    2015-01-01

    Problematic internet use has been associated with a variety of psychological comorbidities, but it relationship with physical illness has not received the same degree of investigation. The current study surveyed 505 participants online, and asked about their levels of problematic internet usage (Internet Addiction Test), depression and anxiety (Hospital Anxiety and Depression Scales), social isolation (UCLA Loneliness Questionnaire), sleep problems (Pittsburgh Sleep Quality Index), and their current health – General Health Questionnaire (GHQ-28), and the Immune Function Questionnaire. The results demonstrated that around 30% of the sample displayed mild or worse levels of internet addiction, as measured by the IAT. Although there were differences in the purposes for which males and females used the internet, there were no differences in terms of levels of problematic usage between genders. The internet problems were strongly related to all of the other psychological variables such as depression, anxiety, social-isolation, and sleep problems. Internet addiction was also associated with reduced self-reported immune function, but not with the measure of general health (GHQ-28). This relationship between problematic internet use and reduced immune function was found to be independent of the impact of the co-morbidities. It is suggested that the negative relationship between level of problematic internet use and immune function may be mediated by levels of stress produced by such internet use, and subsequent sympathetic nervous activity, which related to immune-supressants, such as cortisol. PMID:26244339

  2. Determination of trace phosphorus in high purity tantalum materials by inductively coupled plasma mass spectrometry subsequent to matrix separation with on-line anion exchange/coprecipitation.

    PubMed

    Kozono, Shuji; Takahashi, Shigeto; Haraguchi, Hiroki

    2002-02-01

    An on-line matrix separation/inductively coupled plasma mass spectrometry (ICP-MS) method is proposed for the determination of trace amounts of phosphorus in high purity tantalum metal, tantalum (V) oxide, and tantalum pentaethoxide. In the present method, the matrix tantalum in the sample solution was adsorbed on the anion exchange resin, and phosphorus (phosphate ion) was eluted with the carrier solution of HF and HNO3 mixture. Then, the effluent solution was subsequently mixed with bismuth solution and aqueous ammonia solution to coprecipitate phosphate together with bismuth hydroxide. The precipitate formed was collected on the in-line membrane filter to wash out nitric acid with pure water, and then dissolved with hydrochloric acid. The obtained phosphorus sample solution was introduced directly into the nebulizer of ICP-MS for the determination of phosphorus. Phosphorus was determined at the molecular ion signal of 31P16O+ (m/z 47). The detection limit (3sigma) of phosphorus in the present method was 1.3 ng mL(-1) as the sample solution basis, and the relative standard deviation for 30 ng mL(-1) of phosphorus in the standard solution was 4.3% in the replicate measurements (n=11). The present method was applied to the analysis of high purity tantalum materials. The concentrations of phosphorus in tantalum samples were in fairly good agreement with those obtained by glow discharge mass spectrometry (GDMS). PMID:11939629

  3. Determination of trace sulfur in biodiesel and diesel standard reference materials by isotope dilution sector field inductively coupled plasma mass spectrometry.

    PubMed

    Amais, Renata S; Long, Stephen E; Nóbrega, Joaquim A; Christopher, Steven J

    2014-01-01

    A method is described for quantification of sulfur at low concentrations on the order of mgkg(-1) in biodiesel and diesel fuels using isotope dilution and sector field inductively coupled plasma mass spectrometry (ID-SF-ICP-MS). Closed vessel microwave-assisted digestion was employed using a diluted nitric acid and hydrogen peroxide decomposition medium to reduce sample dilution volumes. Medium resolution mode was employed to eliminate isobaric interferences at (32)S and (34)S related to polyatomic phosphorus and oxygen species, and sulfur hydride species. The method outlined yielded respective limits of detection (LOD) and limits of quantification (LOQ) of 0.7 mg kg(-1) S and 2.5 mg kg(-1) S (in the sample). The LOD was constrained by instrument background counts at (32)S but was sufficient to facilitate value assignment of total S mass fraction in NIST SRM 2723b Sulfur in Diesel Fuel Oil at 9.06±0.13 mg kg(-1). No statistically significant difference at a 95% confidence level was observed between the measured and certified values for certified reference materials NIST SRM 2773 B100 Biodiesel (Animal-Based), CENAM DRM 272b and NIST SRM 2723a Sulfur in Diesel Fuel Oil, validating method accuracy. PMID:24331043

  4. [Determination of poppy ingredients in chafing dish materials by isotopic internal standard coupled with multiple reaction monitoring and online full scan mass spectrometry].

    PubMed

    Zhu, Weixia; Sun, Zhuanlian; Yuan, Ping; Yang, Jizhou; Liu, Yafeng; Sun, Wuyong

    2014-12-01

    A confirmative method was developed for determining five poppy alkaloids including morphine, codeine, papaverine, tibane, noscapine in chafing dish ingredients by high performance liquid chromatography coupled with triple quadrupole linear ion trap mass spectrometry (HPLC-Q Trap MS). The sample was extracted with dilute HCl solution under heating condition. The removal of lipid procedure was performed with hexane. The purification was carried out on a mixed-cation solid-phase extraction column (MCX) and ethyl acetate-methanol containing 5% aqueous ammonia was used for elution. A PAK ST column was used to separate the analytes, and 5 mmol/L ammonium acetate methanol and 10 mmol/L ammonium acetate (pH 3. 6) were used as mobile phases. The five alkaloids was detected in the positive mode simultaneously by multiple reaction monitoring (MRM) and online enhanced product ion full scan (EPI). The LODs were 0.05-0.5 µg/kg and the LOQs were 0. 2-2 µg/kg for the five poppy alkaloids. The overall recoveries of the method varied from 64. 2% to 110. 6%, and the RSD were between 4. 2% and 12. 5%. The EPI mass spectra of positive samples were searched through standard library for qualitative confirmation. The detection of real hot pot material samples showed this method can be used for the simple and accurate determination of the five poppy alkaloid residues in chafing dish. PMID:25902640

  5. Etching of new phase change material Ti0.5Sb2Te3 by Cl2/Ar and CF4/Ar inductively coupled plasmas

    NASA Astrophysics Data System (ADS)

    Zhang, Zhonghua; Song, Sannian; Song, Zhitang; Cheng, Yan; Zhu, Min; Li, Xiaoyun; Zhu, Yueqin; Guo, Xiaohui; Yin, Weijun; Wu, Liangcai; Liu, Bo; Feng, Songlin; Zhou, Dong

    2014-08-01

    The etching characteristics of new phase change material Ti0.5Sb2Te3 (TST) were studied with the Cl2/Ar or CF4/Ar gas mixture using inductively coupled plasmas system. The effects of gas-mixing ratio, bias power, gas pressure, applying ICP power on the variations of etch rate, etch profiles, and surface roughness were investigated, respectively. Furthermore, X-ray photoelectron spectroscopy (XPS) compositional depth profiling was used to determine the surface degradation of etched TST using Cl2/Ar and CF4/Ar gas mixture. The etched TST shows a shift of the peaks related to Sb and Te to a higher energy for both etching gas, indicating the surface degradation of TST after etching. TST etched by Cl2 shows a thicker chloride layer remaining on the etched surface than fluorinate layer etched by CF4 owing to the higher reactivity. In the case of CF4, a thinner C-F polymer layer was observed on the etched surface, indicating lower etch rate due to the difficulty in making F diffusion into the TST through the C-F layer.

  6. The Use of Elasto-Visco-Plastic Material Model Coupled with Pressure-Volume Thermodynamic Relationship to Simulate the Stretch Blow Molding of Polyethylene Terephthalate

    NASA Astrophysics Data System (ADS)

    Mir, H.; Benrabah, Z.; Thibault, F.

    2007-05-01

    The use of polyethylene terephthalate (PET) in the stretch blow molding process presents several challenging issues due to various processing parameters and complex behavior of the material, which is both temperature and strain-rate dependent. In this paper, we generalize the G'Sell-Jonas law in 3D to model and simulate the elasto-visco-plastic (EVP) behavior of PET, taking into account strain-hardening and strain-softening. It is observed that the internal pressure (inside the preform) is significantly different from the nominal pressure (imposed in the blowing device upstream) since the internal pressure and the enclosed volume of the preform are fully coupled. In order to accurately simulate this phenomenon, a thermodynamic model was used to characterize the pressure-volume relationship (PVR). The predicted pressure evolution is thus more realistic when imposing only the machine power of the blowing device (air compressor or vacuum pump). Mechanical and temperature equilibrium equations are fully nonlinear and solved separately with implicit schemes on the current deformed configuration, which is updated at each time step. Biaxial characterization tests were used to determine the model parameters in order to simulate the stretch blow molding process using the pressure-volume thermodynamic relationship. To validate this model, thickness predictions for three industrial cases will be presented and compared to experimental measurements.

  7. A Comparison of English Teachers' Own Usage with Their Attitudes Toward Usage.

    ERIC Educational Resources Information Center

    Johnson, Robert Spencer

    In spoken and written situations which focused the teachers' attentions on information rather than on their language, samples of 100 English teachers' actual language were obtained with respect to five debatable usages: "everybody...their,""reason...is because,""who" as an object pronoun, "will/would" with the first person subject to express…

  8. Worksheet Usage, Reading Achievement, Classes' Lack of Readiness, and Science Achievement: A Cross-Country Comparison

    ERIC Educational Resources Information Center

    Lee, Che-Di

    2014-01-01

    Instructional written materials play important roles as teachers' agents in effective teaching practices. Worksheets are one of the most frequently used materials. In this exploratory study, the relationships between worksheet usage and science achievement in 32 countries were examined through the use of TIMSS and PIRLS data and multiple…

  9. Cleaning optimization for reduced chemical usage

    SciTech Connect

    Resnick, P.J.; Simonson, G.C.; Matlock, C.A.; Kelly, M.J.

    1996-11-01

    The use of dilute SC-1 (NH40H:H202:H20) chemistry cleaning processes for particle removal from silicon surfaces has been investigated. Dilute chemistries can be highly effective, especially when high- frequency acoustic energy (megasonics) is applied. The high particle removal efficacy of the dilute chemistry processes presumably arises due to increased double layer effects caused by reduced ionic strength. Dilute chemistry SC- I solutions exhibit somewhat reduced efficacy for removal of certain light organics; however, when dilute SC-1 is used along with other pre-gate cleaning steps (e.g. HF, SC-2, and piranha), then the overall cleaning sequence is quite effective. In addition to providing robust cleaning processes, dilute chemistries also result in significantly lower chemical and rinse water usage. Waste water treatment requirements are also lessened when dilute chemistry cleaning solutions are employed.

  10. Optimal Repellent Usage to Combat Dengue Fever.

    PubMed

    Dorsett, Chasity; Oh, Hyunju; Paulemond, Marie Laura; Rychtář, Jan

    2016-05-01

    Dengue fever is one of the most important vector-borne diseases. It is transmitted by Aedes Stegomyia aegypti, and one of the most effective strategies to combat the disease is the reduction of exposure to bites of these mosquitoes. In this paper, we present a game-theoretical model in which individuals choose their own level of protection against mosquito bites in order to maximize their own benefits, effectively balancing the cost of protection and the risk of contracting the dengue fever. We find that even when the usage of protection is strictly voluntary, as soon as the cost of protection is about 10,000 times less than the cost of contracting dengue fever, the optimal level of protection will be within 5 % of the level needed for herd immunity. PMID:27142427

  11. Usage-Oriented Topic Maps Building Approach

    NASA Astrophysics Data System (ADS)

    Ellouze, Nebrasse; Lammari, Nadira; Métais, Elisabeth; Ben Ahmed, Mohamed

    In this paper, we present a collaborative and incremental construction approach of multilingual Topic Maps based on enrichment and merging techniques. In recent years, several Topic Map building approaches have been proposed endowed with different characteristics. Generally, they are dedicated to particular data types like text, semi-structured data, relational data, etc. We note also that most of these approaches take as input monolingual documents to build the Topic Map. The problem is that the large majority of resources available today are written in various languages, and these resources could be relevant even to non-native speakers. Thus, our work is driven towards a collaborative and incremental method for Topic Map construction from textual documents available in different languages. To enrich the Topic Map, we take as input a domain thesaurus and we propose also to explore the Topic Map usage which means available potential questions related to the source documents.

  12. Tubular Coupling

    NASA Technical Reports Server (NTRS)

    Rosenbaum, Bernard J. (Inventor)

    2000-01-01

    A system for coupling a vascular overflow graft or cannula to a heart pump. A pump pipe outlet is provided with an external tapered surface which receives the end of a compressible connula. An annular compression ring with a tapered internal bore surface is arranged about the cannula with the tapered internal surface in a facing relationship to the external tapered surface. The angle of inclination of the tapered surfaces is converging such that the spacing between the tapered surfaces decreases from one end of the external tapered surface to the other end thereby providing a clamping action of the tapered surface on a cannula which increases as a function of the length of cannula segment between the tapered surfaces. The annular compression ring is disposed within a tubular locking nut which threadedly couples to the pump and provides a compression force for urging the annular ring onto the cannula between the tapered surfaces. The nut has a threaded connection to the pump body. The threaded coupling to the pump body provides a compression force for the annular ring. The annular ring has an annular enclosure space in which excess cannula material from the compression between the tapered surfaces to "bunch up" in the space and serve as an enlarged annular ring segment to assist holding the cannula in place. The clamped cannula provides a seamless joint connection to the pump pipe outlet where the clamping force is uniformly applied to the cannula because of self alignment of the tapered surfaces. The nut can be easily disconnected to replace the pump if necessary.

  13. Certification of Total Arsenic in Blood and Urine Standard Reference Materials by Radiochemical Neutron Activation Analysis and Inductively Coupled Plasma - Mass Spectrometry

    PubMed Central

    Paul, Rick L.; Davis, W. Clay; Yu, Lee; Murphy, Karen E.; Guthrie, William F.; Leber, Dennis D.; Bryan, Colleen E.; Vetter, Thomas W.; Shakirova, Gulchekhra; Mitchell, Graylin; Kyle, David J.; Jarrett, Jeffery M.; Caldwell, Kathleen L.; Jones, Robert L.; Eckdahl, Steven; Wermers, Michelle; Maras, Melissa; Palmer, C. D.; Verostek, M.F.; Geraghty, C. M.; Steuerwald, Amy J.; Parsons, Patrick J.

    2015-01-01

    A newly developed procedure for determination of arsenic by radiochemical neutron activation analysis (RNAA) was used to measure arsenic at four levels in SRM 955c Toxic Elements in Caprine Blood and at two levels in SRM 2668 Toxic Elements in Frozen Human Urine for the purpose of providing mass concentration values for certification. Samples were freeze-dried prior to analysis followed by neutron irradiation for 3 h at a fluence rate of 1×1014cm−2s−1. After sample dissolution in perchloric and nitric acids, arsenic was separated from the matrix by extraction into zinc diethyldithiocarbamate in chloroform, and 76As quantified by gamma-ray spectroscopy. Differences in chemical yield and counting geometry between samples and standards were monitored by measuring the count rate of a 77As tracer added before sample dissolution. RNAA results were combined with inductively coupled plasma – mass spectrometry (ICP-MS) values from NIST and collaborating laboratories to provide certified values of (10.81 ± 0.54) μg/kg and (213.1 ± 0.73) μg/kg for SRM 2668 Levels I and II, and certified values of (21.66 ± 0.73) μg/kg, (52.7 ± 1.1) μg/kg, and (78.8 ± 4.9) μg/kg for SRM 955c Levels 2, 3, and 4 respectively. Because of discrepancies between values obtained by different methods for SRM 955c Level 1, an information value of < 5 μg/kg was assigned for this material. PMID:26300575

  14. File Usage Analysis and Resource Usage Prediction: a Measurement-Based Study. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Devarakonda, Murthy V.-S.

    1987-01-01

    A probabilistic scheme was developed to predict process resource usage in UNIX. Given the identity of the program being run, the scheme predicts CPU time, file I/O, and memory requirements of a process at the beginning of its life. The scheme uses a state-transition model of the program's resource usage in its past executions for prediction. The states of the model are the resource regions obtained from an off-line cluster analysis of processes run on the system. The proposed method is shown to work on data collected from a VAX 11/780 running 4.3 BSD UNIX. The results show that the predicted values correlate well with the actual. The coefficient of correlation between the predicted and actual values of CPU time is 0.84. Errors in prediction are mostly small. Some 82% of errors in CPU time prediction are less than 0.5 standard deviations of process CPU time.

  15. Usage Of Polyacetal Powders As Laser Ablation Propulsion Propellants

    SciTech Connect

    Sasoh, Akihiro; Ogita, Naoya; Sinko, John E.

    2010-05-06

    We examined impulse characteristics of polyoxymeythylene (POM) powders under irradiation by a TEA (Transversely-Excited at Atmospheric pressure)CO{sub 2} laser pulse. The impulse performance exhibited large scatter due to splashing particles. When the powder was hydraulically compacted to form a disk, the momentum coupling coefficient became comparable with that for bulk material, but the mass consumption was increased by several times.

  16. Web-based pathology practice examination usage

    PubMed Central

    Klatt, Edward C.

    2014-01-01

    Context: General and subject specific practice examinations for students in health sciences studying pathology were placed onto a free public internet web site entitled web path and were accessed four clicks from the home web site menu. Subjects and Methods: Multiple choice questions were coded into. html files with JavaScript functions for web browser viewing in a timed format. A Perl programming language script with common gateway interface for web page forms scored examinations and placed results into a log file on an internet computer server. The four general review examinations of 30 questions each could be completed in up to 30 min. The 17 subject specific examinations of 10 questions each with accompanying images could be completed in up to 15 min each. The results of scores and user educational field of study from log files were compiled from June 2006 to January 2014. Results: The four general review examinations had 31,639 accesses with completion of all questions, for a completion rate of 54% and average score of 75%. A score of 100% was achieved by 7% of users, ≥90% by 21%, and ≥50% score by 95% of users. In top to bottom web page menu order, review examination usage was 44%, 24%, 17%, and 15% of all accessions. The 17 subject specific examinations had 103,028 completions, with completion rate 73% and average score 74%. Scoring at 100% was 20% overall, ≥90% by 37%, and ≥50% score by 90% of users. The first three menu items on the web page accounted for 12.6%, 10.0%, and 8.2% of all completions, and the bottom three accounted for no more than 2.2% each. Conclusions: Completion rates were higher for shorter 10 questions subject examinations. Users identifying themselves as MD/DO scored higher than other users, averaging 75%. Usage was higher for examinations at the top of the web page menu. Scores achieved suggest that a cohort of serious users fully completing the examinations had sufficient preparation to use them to support their pathology

  17. 40 CFR 52.254 - Organic solvent usage.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Organic solvent usage. 52.254 Section 52.254 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.254 Organic solvent usage. (a) This section is applicable in the Sacramento...

  18. Effects of Different Metaphor Usage on Hypertext Learning

    ERIC Educational Resources Information Center

    Merdivan, Ece; Ozdener, Nesrin

    2011-01-01

    There are many studies that offer different opinions on the effects of hypertext usage as an educational tool. Given the differences of opinion, it is useful to research the effects of metaphor usage in hypertext education and the use of hypertext as an educational tool. In this study, the effects of metaphors' uses in constructing the…

  19. Benchmarking Usage Statistics in Collection Management Decisions for Serials

    ERIC Educational Resources Information Center

    Tucker, Cory

    2009-01-01

    Usage statistics are an important metric for making decisions on serials. Although the University of Nevada, Las Vegas (UNLV) Libraries have been collecting usage statistics, the statistics had not frequently been used to make decisions and had not been included in collection development policy. After undergoing a collection assessment, the…

  20. Premarital Contraceptives Usage among Male and Female Adolescents.

    ERIC Educational Resources Information Center

    Hornick, Joesph P.; And Others

    1979-01-01

    Variables important in predicting female contraception usage were found to be those which involved dyadic commitment, conditions of love, self-esteem, and father's occupation (social class). The best predictors of male contraception usage involved experience in dating and internalization of role models via mother's and father's permissiveness.…

  1. Reviewing and Critiquing Computer Learning and Usage among Older Adults

    ERIC Educational Resources Information Center

    Kim, Young Sek

    2008-01-01

    By searching the keywords of "older adult" and "computer" in ERIC, Academic Search Premier, and PsycINFO, this study reviewed 70 studies published after 1990 that address older adults' computer learning and usage. This study revealed 5 prominent themes among reviewed literature: (a) motivations and barriers of older adults' usage of computers, (b)…

  2. A Factor Analytic Study of the Internet Usage Scale

    ERIC Educational Resources Information Center

    Monetti, David M.; Whatley, Mark A.; Hinkle, Kerry T.; Cunningham, Kerry T.; Breneiser, Jennifer E.; Kisling, Rhea

    2011-01-01

    This study developed an Internet Usage Scale (IUS) for use with adolescent populations. The IUS is a 26-item scale that measures participants' beliefs about how their Internet usage impacts their behavior. The sample for this study consisted of 947 middle school students. An exploratory factor analysis with varimax rotation was conducted on the…

  3. Dual Accelerometer Usage Strategy for Onboard Space Navigation

    NASA Technical Reports Server (NTRS)

    Zanetti, Renato; D'Souza, Chris

    2012-01-01

    This work introduces a dual accelerometer usage strategy for onboard space navigation. In the proposed algorithm the accelerometer is used to propagate the state when its value exceeds a threshold and it is used to estimate its errors otherwise. Numerical examples and comparison to other accelerometer usage schemes are presented to validate the proposed approach.

  4. Performing Resource Usage Analysis for a NOTIS System.

    ERIC Educational Resources Information Center

    Hinnebusch, Mark

    1991-01-01

    Outlines methods that the Florida Center for Library Automation (FCLA) has developed to estimate transaction costs and overall demand for NOTIS services. Transaction resource usage analysis is discussed, record structures are explained, institution collection size is considered, and usage and response time by hour of day is described. (six…

  5. What Is the next Trend in Usage Statistics in Libraries?

    ERIC Educational Resources Information Center

    King, Douglas

    2009-01-01

    In answering the question "What is the next trend in usage statistics in libraries?" an eclectic group of respondents has presented an assortment of possibilities, suggestions, complaints and, of course, questions of their own. Undoubtedly, usage statistics collection, interpretation, and application are areas of growth and increasing complexity…

  6. (Not) Hearing Optional Subjects: The Effects of Pragmatic Usage Preferences

    ERIC Educational Resources Information Center

    Mack, Jennifer E.; Clifton, Charles, Jr.; Frazier, Lyn; Taylor, Patrick V.

    2012-01-01

    Previous research has shown that usage preferences (non-categorical constraints on the distribution of syntactic structures) shape many grammatical alternations. In the present study, we show that usage preferences also influence which alternate listeners report hearing when presented with acoustically degraded input. We investigated the English…

  7. 47 CFR 22.907 - Coordination of channel usage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Coordination of channel usage. 22.907 Section 22.907 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.907 Coordination of channel usage. Licensees in...

  8. 47 CFR 22.907 - Coordination of channel usage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Coordination of channel usage. 22.907 Section 22.907 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.907 Coordination of channel usage. Licensees in...

  9. 47 CFR 22.907 - Coordination of channel usage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Coordination of channel usage. 22.907 Section 22.907 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.907 Coordination of channel usage. Licensees in...

  10. 47 CFR 22.907 - Coordination of channel usage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Coordination of channel usage. 22.907 Section 22.907 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.907 Coordination of channel usage. Licensees in...

  11. Faculty Usage of Library Tools in a Learning Management System

    ERIC Educational Resources Information Center

    Leeder, Chris; Lonn, Steven

    2014-01-01

    To better understand faculty attitudes and practices regarding usage of library-specific tools and roles in a university learning management system, log data for a period of three semesters was analyzed. Academic departments with highest rates of usage were identified, and faculty users and nonusers within those departments were surveyed regarding…

  12. An Exploratory Study of Internet Addiction, Usage and Communication Pleasure.

    ERIC Educational Resources Information Center

    Chou, Chien; Chou, Jung; Tyan, Nay-Ching Nancy

    This study examined the correlation between Internet addiction, usage, and communication pleasure. Research questions were: (1) What is computer network addiction? (2) How can one measure the degree of computer network addiction? (3) What is the correlation between the degree of users' network addiction and their network usage? (4) What is the…

  13. Journal Usage at Department and Research Group Level

    ERIC Educational Resources Information Center

    McCullough, Ian

    2016-01-01

    Journal usage in the Department of Polymer Science at the University of Akron from 2006 to 2011 was determined by counting citations within faculty-supervised dissertations and faculty publications. Ranked title lists were created and correlations between journal usage in faculty publications and faculty-supervised dissertations were measured…

  14. Effect of service usage on tensile, fatigue, and fracture properties of 7075-T6 and 7178-T6 aluminum alloys

    NASA Technical Reports Server (NTRS)

    Everett, R. A., Jr.

    1975-01-01

    A study has been made to determine the effects of extensive service usage on some basic material properties of 7075-T6 and 7178-T6 aluminum alloy materials. The effects of service usage were determined by comparing material properties for new material (generally obtained from the literature) with those for material cut from the center wing box of a C-130B transport airplane with 6385 flight-hours of service. The properties investigated were notched and unnotched fatigue strengths, fatigue-crack-growth rate, fracture toughness, and tensile properties. For the properties investigated and the parameter ranges considered (crack length, stress ratio, etc.), the results obtained showed no significant difference between service and new materials.

  15. Codon Usage Domains over Bacterial Chromosomes

    PubMed Central

    Bailly-Bechet, Marc; Danchin, Antoine; Iqbal, Mudassar; Marsili, Matteo; Vergassola, Massimo

    2006-01-01

    The geography of codon bias distributions over prokaryotic genomes and its impact upon chromosomal organization are analyzed. To this aim, we introduce a clustering method based on information theory, specifically designed to cluster genes according to their codon usage and apply it to the coding sequences of Escherichia coli and Bacillus subtilis. One of the clusters identified in each of the organisms is found to be related to expression levels, as expected, but other groups feature an over-representation of genes belonging to different functional groups, namely horizontally transferred genes, motility, and intermediary metabolism. Furthermore, we show that genes with a similar bias tend to be close to each other on the chromosome and organized in coherent domains, more extended than operons, demonstrating a role of translation in structuring bacterial chromosomes. It is argued that a sizeable contribution to this effect comes from the dynamical compartimentalization induced by the recycling of tRNAs, leading to gene expression rates dependent on their genomic and expression context. PMID:16683018

  16. Differential receptor usage by measles virus strains.

    PubMed

    Bartz, R; Firsching, R; Rima, B; ter Meulen, V; Schneider-Schaulies, J

    1998-05-01

    Recently, we demonstrated that infection of cells with all measles virus (MV) strains tested was inhibited by antibodies against CD46, although not all strains caused downregulation of the MV receptor CD46 from the surface of human cells. We now show that infection of cells with MV strain WTFb, a variant of wild-type isolate WTF which has been isolated and propagated on human BJAB cells, is not inhibited by antibodies against CD46. In contrast, infection of cells with the closely related strain WTFv, a Vero cell-adapted variant of WTF, is inhibited by antibodies against CD46. This observation led us to investigate the interaction of these viruses and the vaccine strain Edmonston (Edm) with CD46 and target cells. Cellular receptors with high affinity binding for WTFb are present on BJAB cells, but not on transfected CD46-expressing CHO cells. In contrast to the Edm strain, virus particles and solubilized envelope glycoproteins of WTFb have a very limited binding capacity to CD46. Furthermore, we show that recombinant soluble CD46 either does not bind, or binds very weakly, to WTFb glycoproteins expressed on the cell surface. Our findings indicate that wild-type MV strain WTFb and vaccine strain Edm use different binding sites on human cells. In addition, the results suggest that MV strains may alternatively use CD46 and an unknown molecule as receptors, and that the degree of usage of both receptors may be MV strain-specific. PMID:9603316

  17. T cell receptor usage in rheumatic disease.

    PubMed

    Richardson, B C

    1992-01-01

    Protection against microbial attack or invasion is a fundamental function of the immune system. Crucial to this function is the ability to distinguish "self" from the invading organism, and tolerate "self" while removing "non-self". The ability to distinguish self from non-self is not inherent in the immune system, but rather is acquired and continuously maintained. Unfortunately, the mechanisms maintaining self-tolerance are not perfect, and at times break down. In these instances an autoimmune disease results. T cells initiate normal immune responses, and it is now clear that T cells can also initiate pathologic immune responses. In animal models, T cells produce diseases resembling rheumatoid arthritis (RA) (1-3), systemic lupus erythematosus (4-6) and progressive systemic sclerosis (7,8). It is likely that T cells participate in human autoimmune diseases as well. The molecular basis of T cell antigen recognition has been clarified over the past decade. These advances now allow direct examination of the T cell receptor (TCR) molecules participating in autoimmune responses, and raise the exciting possibility that the cells inducing autoimmune responses may finally be identified. Selective agents might then be developed which would interfere with or inhibit the cells. Understanding these developments requires detailed knowledge of how T cells recognize antigen, and of the receptors involved in autoimmune diseases. This article reviews the current literature on T cell receptor structure, and summarizes what is currently known about the usage of specific T cell receptors in autoimmune rheumatic disease. PMID:1582073

  18. Codon catalog usage and the genome hypothesis.

    PubMed Central

    Grantham, R; Gautier, C; Gouy, M; Mercier, R; Pavé, A

    1980-01-01

    Frequencies for each of the 61 amino acid codons have been determined in every published mRNA sequence of 50 or more codons. The frequencies are shown for each kind of genome and for each individual gene. A surprising consistency of choices exists among genes of the same or similar genomes. Thus each genome, or kind of genome, appears to possess a "system" for choosing between codons. Frameshift genes, however, have widely different choice strategies from normal genes. Our work indicates that the main factors distinguishing between mRNA sequences relate to choices among degenerate bases. These systematic third base choices can therefore be used to establish a new kind of genetic distance, which reflects differences in coding strategy. The choice patterns we find seem compatible with the idea that the genome and not the individual gene is the unit of selection. Each gene in a genome tends to conform to its species' usage of the codon catalog; this is our genome hypothesis. PMID:6986610

  19. Poultry industry trends for litter usage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Broiler litter, a combination of primarily organic bedding material and excreta, has been routinely applied for decades as fertilizer. Poultry litter improves soil quality by adding organic material, an advantage over commercial fertilizers. Once a hindrance to be disposed, rising costs of commerc...

  20. Usage of Alternative, Environmentally Acceptable Materials—Experience from Eastern Croatia

    NASA Astrophysics Data System (ADS)

    Barišić, I.; Zagvozda, M.; Dimter, S.

    2015-11-01

    The concept of sustainability should be the main guiding principle in the construction industry today. It mandates conservation of natural resources and thus lower impact on the environment. In road construction, part of construction industry that consumes largest quantities of natural materials, sustainable building and maintenance of roads is possible trough application of secondary materials. Usage of industrial and construction waste presents energy, ecologically and financially effective alternative. Republic of Croatia, even as a new member of the European Union, still lags behind the well-established practices of the application of alternative materials in different European countries. The reasons for this can be found in the current legal and technical regulations for alternative materials. In this paper, the existing regulations for alternative materials and the impact they have on the application of these materials in practice in the region of eastern Croatia will be shown.

  1. Application Examples for Handle System Usage

    NASA Astrophysics Data System (ADS)

    Toussaint, F.; Weigel, T.; Thiemann, H.; Höck, H.; Stockhause, M.; Lautenschlager, M.

    2012-12-01

    Besides the well-known DOI (Digital Object Identifiers) as a special form of Handles that resolve to scientific publications there are various other applications in use. Others perhaps are just not yet. We present some examples for the existing ones and some ideas for the future. The national German project C3-Grid provides a framework to implement a first solution for provenance tracing and explore unforeseen implications. Though project-specific, the high-level architecture is generic and represents well a common notion of data derivation. Users select one or many input datasets and a workflow software module (an agent in this context) to execute on the data. The output data is deposited in a repository to be delivered to the user. All data is accompanied by an XML metadata document. All input and output data, metadata and the workflow module receive Handles and are linked together to establish a directed acyclic graph of derived data objects and involved agents. Data that has been modified by a workflow module is linked to its predecessor data and the workflow module involved. Version control systems such as svn or git provide Internet access to software repositories using URLs. To refer to a specific state of the source code of for instance a C3 workflow module, it is sufficient to reference the URL to the svn revision or git hash. In consequence, individual revisions and the repository as a whole receive PIDs. Moreover, the revision specific PIDs are linked to their respective predecessors and become part of the provenance graph. Another example for usage of PIDs in a current major project is given in EUDAT (European Data Infrastructure) which will link scientific data of several research communities together. In many fields it is necessary to provide data objects at multiple locations for a variety of applications. To ensure consistency, not only the master of a data object but also its copies shall be provided with a PID. To verify transaction safety and to

  2. The usage of blood components in obstetrics.

    PubMed

    Adukauskienė, Dalia; Veikutienė, Audronė; Adukauskaitė, Agnė; Veikutis, Vincentas; Rimaitis, Kęstutis

    2010-01-01

    Major obstetric hemorrhage remains the leading cause of maternal morbidity and mortality worldwide. Even though blood transfusion may be a life-saving procedure, an inappropriate usage of blood products in obstetric emergencies especially in cases of massive bleeding is associated with increased morbidity and risk of death. Thorough knowledge of the etiology, pathophysiology, and optimal therapeutic options of major obstetric hemorrhage may help to avoid lethal outcomes. There are evidence-based data about some risks related with transfusion of blood components: acute or delayed hemolytic, febrile, allergic reactions, transfusion-related acute lung injury, negative immunomodulative effect, transmission of infectious diseases, dissemination of cancer. This is why the indications for allogeneic blood transfusion are restricted, and new safer methods are being discovered to decrease the requirement for it. Red cell alloimmunization may develop in pregnancy; therefore, all pregnant women should pass screening for irregular antibodies. Antierythrocytic irregular antibodies may occur due to previous pregnancies or allogeneic red blood cell transfusions, and it is important for blood cross-matching in the future. Under certain circumstances, such as complicated maternal history, severe coagulation abnormalities, severe anemia, the preparation of cross-matched blood is necessary. There is evidence of very significant variation in the use of blood products (red cells, platelets, fresh frozen plasma, or cryoprecipitate) among clinicians in various medical institutions, and sometimes indications for transfusion are not correctly motivated. The transfusion of each single blood product must be performed only in case of evaluation of expected effect. The need for blood products and for their combination is necessary to estimate for each patient individually in case of obstetric emergencies either. Indications for transfusion of blood components in obstetrics are presented in

  3. Energy Usage Optimisation in South African Mines

    NASA Astrophysics Data System (ADS)

    Hasan, Ali; Twala, Bhekisipho; Ouahada, Khmaies; Marwala, Tshilidzi

    2014-03-01

    In recent years, South Africa has encountered a critical electricity supply which necessitated the implementation of demand-side management (DSM) projects. Load shifting and energy (EE) efficiency projects were introduced in mining sector to reduce the electricity usage during day peak time. As the compressed air networks and the water pumping systems are using large amounts of the mines' electricity, possible ways were investigated and implemented to improve and optimise the energy consumption and to reduce the costs. Implementing DSM and EE in four different mines resulted in achieving the desired energy savings and load-shifting. W ostatnich latach w Południowej Afryce zanotowano pewne trudności z dostawami energii elektrycznej, co wymusiło wdrożenie działań mających na celu skuteczne zarządzanie zagadnieniami energetycznymi. Wprowadzono działania mające na celu zmianę systemu obciążeń roboczych i bardziej efektywne wykorzystanie energii tak, by obniżyć zapotrzebowanie na energię w trakcie szczytowych godzin w ciągu dnia. Sieci dostarczające sprężone powietrze oraz stacje pomp zużywają znaczne ilości energii w kopalni, przeanalizowano więc możliwe sposoby redukcji i optymalizacji zapotrzebowania na energię i tym samym obniżenia kosztów produkcji. Wdrożenie odpowiednich projektów nakierowanych na oszczędności i optymalizację w czterech kopalniach doprowadziło do oczekiwanych oszczędności energii i umożliwiło zmianę systemu obciążeń roboczych w trakcie procesu produkcji.

  4. Towards the Application of Structure-Property Relationship Modeling in Materials Science: Predicting the Seebeck Coefficient for Ionic Liquid/Redox Couple Systems.

    PubMed

    Sosnowska, Anita; Barycki, Maciej; Gajewicz, Agnieszka; Bobrowski, Maciej; Freza, Sylwia; Skurski, Piotr; Uhl, Stefanie; Laux, Edith; Journot, Tony; Jeandupeux, Laure; Keppner, Herbert; Puzyn, Tomasz

    2016-06-01

    This work focuses on determining the influence of both ionic-liquid (IL) type and redox couple concentration on Seebeck coefficient values of such a system. The quantitative structure-property relationship (QSPR) and read-across techniques are proposed as methods to identify structural features of ILs (mixed with LiI/I2 redox couple), which have the most influence on the Seebeck coefficient (Se ) values of the system. ILs consisting of small, symmetric cations and anions with high values of vertical electron binding energy are recognized as those with the highest values of Se . In addition, the QSPR model enables the values of Se to be predicted for each IL that belongs to the applicability domain of the model. The influence of the redox-couple concentration on values of Se is also quantitatively described. Thus, it is possible to calculate how the value of Se will change with changing redox-couple concentration. The presence of the LiI/I2 redox couple in lower concentrations increases the values of Se , as expected. PMID:26919483

  5. Synonymous codon usage pattern in glycoprotein gene of rabies virus.

    PubMed

    Morla, Sudhir; Makhija, Aditi; Kumar, Sachin

    2016-06-10

    Rabies virus (RABV) is the causative agent of a fatal nervous system ailment. The disease is zoonotic and prevalent in many developing countries. The glycoprotein (G) of RABV is the major antigenic determinant of the virus and plays a pivotal role in its neurovirulence. Various aspects of 'G' protein biology have been explored, but the factors affecting the nucleotide choice and synonymous codon usage have never been reported. In the present study, we have analyzed the relative synonymous codon usage and effective number of codons (Nc) using 132 'G' protein genes of RABV. Corresponding analysis was used to calculate major trends in codon usage. The correlation between base composition and codon usage as well as the plot between Nc and GC3 suggest that mutational pressure is the major factor that influences the codon usage in the G gene of RABV. In addition, factors like aromaticity, aliphatic index and hydropathy have shown slight correlation suggesting that natural selection also contributes to the codon usage variations of the 'G' gene. In conclusion, codon usage bias in 'G' gene of RABV is mainly by mutational pressure and natural selection. PMID:26945626

  6. Usage and Recall of the Food Stamp Office Resource Kit (FSORK) by Food Stamp Applicants in 4 California Counties

    ERIC Educational Resources Information Center

    Ghirardelli, Alyssa; Linares, Amanda; Fong, Amy

    2011-01-01

    Objective: To evaluate recall and usage of the Food Stamp Office Resource Kit (FSORK), a set of nutrition education materials designed for use in food stamp offices. Design: Client intercept exit surveys, an environmental scan, and individual observations of clients in the food stamp office. Setting: Four food stamp offices in California.…

  7. Internet as an Information Source: Attitudes and Usage of Students Enrolled in a College of Agriculture Course

    ERIC Educational Resources Information Center

    Rhoades, Emily B.; Irani, Tracy; Telg, Ricky; Myers, Brian E.

    2008-01-01

    With Internet usage in the United States at an all-time high, information technology use in education has continued to increase. Research has shown that many students are utilizing these materials to search out information and assist with completing class assignments. Many college students have described the Internet as a functional tool that…

  8. Analysis of amino acid and codon usage in Paramecium bursaria.

    PubMed

    Dohra, Hideo; Fujishima, Masahiro; Suzuki, Haruo

    2015-10-01

    The ciliate Paramecium bursaria harbors the green-alga Chlorella symbionts. We reassembled the P. bursaria transcriptome to minimize falsely fused transcripts, and investigated amino acid and codon usage using the transcriptome data. Surface proteins preferentially use smaller amino acid residues like cysteine. Unusual synonymous codon and amino acid usage in highly expressed genes can reflect a balance between translational selection and other factors. A correlation of gene expression level with synonymous codon or amino acid usage is emphasized in genes down-regulated in symbiont-bearing cells compared to symbiont-free cells. Our results imply that the selection is associated with P. bursaria-Chlorella symbiosis. PMID:26341535

  9. CFL3D Version 6.4-General Usage and Aeroelastic Analysis

    NASA Technical Reports Server (NTRS)

    Bartels, Robert E.; Rumsey, Christopher L.; Biedron, Robert T.

    2006-01-01

    This document contains the course notes on the computational fluid dynamics code CFL3D version 6.4. It is intended to provide from basic to advanced users the information necessary to successfully use the code for a broad range of cases. Much of the course covers capability that has been a part of previous versions of the code, with material compiled from a CFL3D v5.0 manual and from the CFL3D v6 web site prior to the current release. This part of the material is presented to users of the code not familiar with computational fluid dynamics. There is new capability in CFL3D version 6.4 presented here that has not previously been published. There are also outdated features no longer used or recommended in recent releases of the code. The information offered here supersedes earlier manuals and updates outdated usage. Where current usage supersedes older versions, notation of that is made. These course notes also provides hints for usage, code installation and examples not found elsewhere.

  10. Flow injection on-line solid phase extraction coupled with inductively coupled plasma mass spectrometry for determination of (ultra)trace rare earth elements in environmental materials using maleic acid grafted polytetrafluoroethylene fibers as sorbent.

    PubMed

    Wang, Zhao-Hui; Yan, Xiu-Ping; Wang, Zhi-Peng; Zhang, Zheng-Pu; Liu, Li-Wen

    2006-09-01

    A new sorbent, maleic acid grafted polytetrafluoroethylene fiber (MA-PTFE), was prepared and evaluated for on-line solid-phase extraction coupled with inductively coupled plasma mass spectrometry (ICP-MS) for fast, selective, and sensitive determination of (ultra)trace rare earth elements (REEs) in environmental samples. The REEs in aqueous samples at pH = 3.0 were selectively extracted onto a microcolumn packed with the MA-PTFE fiber, and the adsorbed REEs were subsequently eluted on-line with 0.9 mol l(-1) HNO3 for ICP-MS determination. The new sorbent extraction system allows effective preconcentration and separation of the REEs from the major matrix constituents of alkali and alkali earth elements, particularly their separation from barium that produces considerable isobaric interferences of 134Ba16O1H+, 135Ba16O+, 136Ba16O1H+, and 137Ba16O+ on 151Eu+ and 153Eu+. With the use of a sample loading flow rate of 7.4 ml min(-1) for 120 s preconcentration, enhancement factors of 69-97 and detection limits (3s) of 1-20 pg l(-1) were achieved at a sample throughput of 22 samples h(-1). The precision (RSD) for 16 replicate determinations of 50 ng l(-1) of REEs was 0.5-1.1%. The developed method was successfully applied to the determination of (ultra)trace REEs in sediment, soil, and seawater samples. PMID:16814561

  11. Aperture size, materiality of the secondary room and listener location: Impact on the simulated impulse response of a coupled-volume concert hall

    NASA Astrophysics Data System (ADS)

    Ermann, Michael; Johnson, Marty E.; Harrison, Byron W.

    2003-04-01

    By adding a second room to a concert hall, and designing doors to control the sonic transparency between the two rooms, designers can create a new, coupled acoustic. Concert halls use coupling to achieve a variable, longer and distinct reverberant quality for their musicians and listeners. For this study, a coupled-volume concert hall based on an existing performing arts center is conceived and computer-modeled. It has a fixed geometric volume, form and primary-room sound absorption. Ray-tracing software simulates impulse responses, varying both aperture size and secondary-room sound absorption level, across a grid of receiver (listener) locations. The results are compared with statistical analysis that suggests a highly sensitive relationship between the double-sloped condition and the architecture of the space. This line of study aims to quantitatively and spatially correlate the double-sloped condition with (1) aperture size exposing the chamber, (2) sound absorptance in the coupled volume, and (3) listener location.

  12. Aperture size, materiality of the secondary room, and listener location: Impact on the simulated impulse response of a coupled-volume concert hall

    NASA Astrophysics Data System (ADS)

    Ermann, Michael; Johnson, Marty E.; Harrison, Byron W.

    2002-11-01

    By adding a second room to a concert hall, and designing doors to control the sonic transparency between the two rooms, designers can create a new, coupled acoustic. Concert halls use coupling to achieve a variable, longer, and distinct reverberant quality for their musicians and listeners. For this study, a coupled-volume concert hall based on an existing performing arts center is conceived and computer modeled. It has a fixed geometric volume, form, and primary-room sound absorption. Ray-tracing software simulates impulse responses, varying both aperture size and secondary-room sound-absorption level, across a grid of receiver (listener) locations. The results are compared with statistical analysis that suggests a highly sensitive relationship between the double-sloped condition and the architecture of the space. This line of study aims to quantitatively and spatially correlate the double-sloped condition with (1) aperture size exposing the chamber, (2) sound absorptance in the coupled volume, and (3) listener location.

  13. Feasibility Study of a Rotorcraft Health and Usage Monitoring System (HUMS): Usage and Structural Life Monitoring Evaluation

    NASA Technical Reports Server (NTRS)

    Dickson, B.; Cronkhite, J.; Bielefeld, S.; Killian, L.; Hayden, R.

    1996-01-01

    The objective of this study was to evaluate two techniques, Flight Condition Recognition (FCR) and Flight Load Synthesis (FIS), for usage monitoring and assess the potential benefits of extending the retirement intervals of life-limited components, thus reducing the operator's maintenance and replacement costs. Both techniques involve indirect determination of loads using measured flight parameters and subsequent fatigue analysis to calculate the life expended on the life-limited components. To assess the potential benefit of usage monitoring, the two usage techniques were compared to current methods of component retirement. In addition, comparisons were made with direct load measurements to assess the accuracy of the two techniques.

  14. Everyday Preschool Interpersonal Speech Usage: Methodological, Developmental, and Sociolinguistic Studies

    ERIC Educational Resources Information Center

    Schachter, Frances Fuchs; And Others

    1974-01-01

    Reports on a study designed to provide data on developmental and sociolinguistic patterns of interpersonal speech usage from ages 2 to 5 years which may have important implications for poverty school programs. (Author/CS)

  15. Comprehensive Nuclear Materials

    SciTech Connect

    Konings, Dr. Rudy J. M.; Allen, Todd R.; Stoller, Roger E; Yamanaka, Prof. Shinsuke

    2012-01-01

    This book encompasses a rich seam of current information on the vast and multidisciplinary field of nuclear materials employed in fission and prototype fusion systems. Discussion includes both historical and contemporary international research in nuclear materials, from Actinides to Zirconium alloys, from the worlds leading scientists and engineers. Synthesizes pertinent current science to support the selection, assessment, validation and engineering of materials in extreme nuclear environments. The work discusses the major classes of materials suitable for usage in nuclear fission, fusion reactors and high power accelerators, and for diverse functions in fuels, cladding, moderator and control materials, structural, functional, and waste materials.

  16. Helix coupling

    DOEpatents

    Ginell, W.S.

    1982-03-17

    A coupling for connecting helix members in series, which consists of a pair of U-shaped elements, one of which is attached to each helix end with the U sections of the elements interlocked. The coupling is particularly beneficial for interconnecting helical Nitinol elements utilized in thermal actuators or engines. Each coupling half is attached to the associated helix at two points, thereby providing axial load while being easily removed from the helix, and reusable.

  17. Helix coupling

    DOEpatents

    Ginell, William S.

    1989-04-25

    A coupling for connecting helix members in series, which consists of a pair of U-shaped elements, one of which is attached to each helix end with the "U" sections of the elements interlocked. The coupling is particularly beneficial for interconnecting helical Nitinol elements utilized in thermal actuators or engines. Each coupling half is attached to the associated helix at two points, thereby providing axial load while being easily removed from the helix, and reusable.

  18. Genome-wide analysis of codon usage bias in Ebolavirus.

    PubMed

    Cristina, Juan; Moreno, Pilar; Moratorio, Gonzalo; Musto, Héctor

    2015-01-22

    Ebola virus (EBOV) is a member of the family Filoviridae and its genome consists of a 19-kb, single-stranded, negative sense RNA. EBOV is subdivided into five distinct species with different pathogenicities, being Zaire ebolavirus (ZEBOV) the most lethal species. The interplay of codon usage among viruses and their hosts is expected to affect overall viral survival, fitness, evasion from host's immune system and evolution. In the present study, we performed comprehensive analyses of codon usage and composition of ZEBOV. Effective number of codons (ENC) indicates that the overall codon usage among ZEBOV strains is slightly biased. Different codon preferences in ZEBOV genes in relation to codon usage of human genes were found. Highly preferred codons are all A-ending triplets, which strongly suggests that mutational bias is a main force shaping codon usage in ZEBOV. Dinucleotide composition also plays a role in the overall pattern of ZEBOV codon usage. ZEBOV does not seem to use the most abundant tRNAs present in the human cells for most of their preferred codons. PMID:25445348

  19. A machine learning approach for detecting cell phone usage

    NASA Astrophysics Data System (ADS)

    Xu, Beilei; Loce, Robert P.

    2015-03-01

    Cell phone usage while driving is common, but widely considered dangerous due to distraction to the driver. Because of the high number of accidents related to cell phone usage while driving, several states have enacted regulations that prohibit driver cell phone usage while driving. However, to enforce the regulation, current practice requires dispatching law enforcement officers at road side to visually examine incoming cars or having human operators manually examine image/video records to identify violators. Both of these practices are expensive, difficult, and ultimately ineffective. Therefore, there is a need for a semi-automatic or automatic solution to detect driver cell phone usage. In this paper, we propose a machine-learning-based method for detecting driver cell phone usage using a camera system directed at the vehicle's front windshield. The developed method consists of two stages: first, the frontal windshield region localization using the deformable part model (DPM), next, we utilize Fisher vectors (FV) representation to classify the driver's side of the windshield into cell phone usage violation and non-violation classes. The proposed method achieved about 95% accuracy with a data set of more than 100 images with drivers in a variety of challenging poses with or without cell phones.

  20. Evaluation of the usage of an object-oriented lesson model to be implemented in medical virtual learning environments.

    PubMed

    Staccini, Pascal; Joubert, Michel; Fieschi, Marius

    2006-01-01

    One of the main aims of learning platforms is to guide students towards interaction with learning activities. Pedagogically, these activities should be connected and well-integrated in a coherent environment. Faced with the increasing demand of medical school faculty and for online delivery of course materials, we designed an integrated and generic lesson model. This was implemented in an original virtual-learning environment. The platform was programmed within an object-oriented content management system embedding a workflow engine. This paper provides a description of the lesson model and the comparative evaluation of its usage by students of two medical curricula. Web usage mining techniques were applied to identify navigation patterns. The monitoring of student behavior in terms of usage is discussed to help student follow-up and optimize tutoring arrangements. PMID:17238440

  1. Stable optical oxygen sensing materials based on click-coupling of fluorinated platinum(II) and palladium(II) porphyrins—A convenient way to eliminate dye migration and leaching

    PubMed Central

    Koren, Klaus; Borisov, Sergey M.; Klimant, Ingo

    2012-01-01

    Nucleophilic substitution of the labile para-fluorine atoms of 2,3,4,5,6-pentafluorophenyl groups enables a click-based covalent linkage of an oxygen indicator (platinum(II) or palladium(II) 5,10,15,20-meso-tetrakis-(2,3,4,5,6-pentafluorophenyl)-porphyrin) to the sensor matrix. Copolymers of styrene and pentafluorostyrene are chosen as polymeric materials. Depending on the reaction conditions either soluble sensor materials or cross-linked microparticles are obtained. Additionally, we prepared Ormosil-based sensors with linked indicator, which showed very high sensitivity toward oxygen. The effect of covalent coupling on sensor characteristics, stability and photophysical properties is studied. It is demonstrated that leaching and migration of the dye are eliminated in the new materials but excellent photophysical properties of the indicators are preserved. PMID:23576845

  2. Using Microsoft Excel to Generate Usage Statistics

    ERIC Educational Resources Information Center

    Spellman, Rosemary

    2011-01-01

    At the Libraries Service Center, statistics are generated on a monthly, quarterly, and yearly basis by using four Microsoft Excel workbooks. These statistics provide information about what materials are being requested and by whom. They also give details about why certain requests may not have been filled. Utilizing Excel allows for a shallower…

  3. Tracking Actual Usage: The Attention Metadata Approach

    ERIC Educational Resources Information Center

    Wolpers, Martin; Najjar, Jehad; Verbert, Katrien; Duval, Erik

    2007-01-01

    The information overload in learning and teaching scenarios is a main hindering factor for efficient and effective learning. New methods are needed to help teachers and students in dealing with the vast amount of available information and learning material. Our approach aims to utilize contextualized attention metadata to capture behavioural…

  4. Feasibility Study of a Rotorcraft Health and Usage Monitoring System ( HUMS): Usage and Structural Life Monitoring Evaluation

    NASA Technical Reports Server (NTRS)

    Dickson, B.; Cronkhite, J.; Bielefeld, S.; Killian, L.; Hayden, R.

    1996-01-01

    The objective of this study was to evaluate two techniques, Flight Condition Recognition (FCR) and Flight Load Synthesis (FLS), for usage monitoring and assess the potential benefits of extending the retirement intervals of life-limited components, thus reducing the operator's maintenance and replacement costs. Both techniques involve indirect determination of loads using measured flight parameters and subsequent fatigue analysis to calculate the life expended on the life-limited components. To assess the potential benefit of usage monitoring, the two usage techniques were compared to current methods of component retirement. In addition, comparisons were made with direct load measurements to assess the accuracy of the two techniques. The data that was used for the evaluation of the usage monitoring techniques was collected under an independent HUMS Flight trial program, using a commercially available HUMS and data recording system. The usage data collect from the HUMS trial aircraft was analyzed off-line using PC-based software that included the FCR and FLS techniques. In the future, if the technique prove feasible, usage monitoring would be incorporated into the onboard HUMS.

  5. Evaluating Junior Secondary Science Textbook Usage in Australian Schools

    NASA Astrophysics Data System (ADS)

    McDonald, Christine V.

    2016-08-01

    A large body of research has drawn attention to the importance of providing engaging learning experiences in junior secondary science classes, in an attempt to attract more students into post-compulsory science courses. The reality of time and resource constraints, and the high proportion of non-specialist science teachers teaching science, has resulted in an overreliance on more transmissive pedagogical tools, such as textbooks. This study sought to evaluate the usage of junior secondary science textbooks in Australian schools. Data were collected via surveys from 486 schools teaching junior secondary (years 7-10), representing all Australian states and territories. Results indicated that most Australian schools use a science textbook in the junior secondary years, and textbooks are used in the majority of science lessons. The most highly cited reason influencing choice of textbook was layout/colour/illustrations, and electronic technologies were found to be the dominant curricula material utilised, in addition to textbooks, in junior secondary science classes. Interestingly, the majority of respondents expressed high levels of satisfaction with their textbooks, although many were keen to stress the subsidiary role of textbooks in the classroom, emphasising the textbook was `one' component of their teaching repertoire. Importantly, respondents were also keen to stress the benefits of textbooks in supporting substitute teachers, beginning teachers, and non-specialist science teachers; in addition to facilitating continuity of programming and staff support in schools with high staff turnover. Implications from this study highlight the need for high quality textbooks to support teaching and learning in Australian junior secondary science classes.

  6. [Preliminary processing, processing and usage of Dendrobii Caulis in history].

    PubMed

    Yang, Wen-yu; Tang, Sheng; Shi, Dong-jun; Chen, Xiang-gui; Li, Ming-yuan; Tang, Xian-fu; Yuan, Chang-jiang

    2015-07-01

    On account of the dense cuticles of the fresh stem and the light, hard and pliable texture of the dried stem, Dendrobii Caulis is difficult to dry or pulverize. So, it is very important to the ancient doctors that Dendrobii Caulis should be properly treated and applied to keep or evoke its medicinal effects. The current textual research results about the preliminary processing, processing and usage methods of Dendrobii Caulis showed that: (1) In history the clinical use of fresh or processed Dendrobii Caulis as teas and tinctures were very common. (2) Its roots and rhizomes would be removed before using. (3) Some ancillary approaches were applied to shorten drying times, such as rinsing with boiling mulberry-ash soup, washing or soaking with liquor, mixing with rice pulp and then basking, etc. (4) According to the ancients knowledge, the sufficient pulverization, by means of slicing, rasping, hitting or pestling techniques, was necessary for Dendrobii Caulis to take its effects. (5) The heat processing methods for Dendrobii Caulis included stir-baking, stir-frying, steaming, decocting and stewing techniques, usually with liquor as an auxiliary material. Among above mentioned, steaming by pretreating with liquor was most commonly used, and this scheme was colorfully drawn in Bu Yi Lei Gong Pao Zhi Bian Lan (Ming Dynasty, 1591 CE) ; moreover, decocting in advance or long-time simmering so as to prepare paste products were recommended in the Qing Dynasty. (6) Some different processing programs involving stir-baking with grit, air-tightly baking with ondol (Kangs), fumigating with sulfur, which appeared in modern times and brought attractive outward appearance of the drug, went against ancients original intentions of ensuring drug efficacy. PMID:26666046

  7. Evaluating Junior Secondary Science Textbook Usage in Australian Schools

    NASA Astrophysics Data System (ADS)

    McDonald, Christine V.

    2015-04-01

    A large body of research has drawn attention to the importance of providing engaging learning experiences in junior secondary science classes, in an attempt to attract more students into post-compulsory science courses. The reality of time and resource constraints, and the high proportion of non-specialist science teachers teaching science, has resulted in an overreliance on more transmissive pedagogical tools, such as textbooks. This study sought to evaluate the usage of junior secondary science textbooks in Australian schools. Data were collected via surveys from 486 schools teaching junior secondary (years 7-10), representing all Australian states and territories. Results indicated that most Australian schools use a science textbook in the junior secondary years, and textbooks are used in the majority of science lessons. The most highly cited reason influencing choice of textbook was layout/colour/illustrations, and electronic technologies were found to be the dominant curricula material utilised, in addition to textbooks, in junior secondary science classes. Interestingly, the majority of respondents expressed high levels of satisfaction with their textbooks, although many were keen to stress the subsidiary role of textbooks in the classroom, emphasising the textbook was `one' component of their teaching repertoire. Importantly, respondents were also keen to stress the benefits of textbooks in supporting substitute teachers, beginning teachers, and non-specialist science teachers; in addition to facilitating continuity of programming and staff support in schools with high staff turnover. Implications from this study highlight the need for high quality textbooks to support teaching and learning in Australian junior secondary science classes.

  8. Spin susceptibility and electron-phonon coupling of two-dimensional materials by range-separated hybrid density functionals: Case study of LixZrNCl

    NASA Astrophysics Data System (ADS)

    Pamuk, Betül; Baima, Jacopo; Dovesi, Roberto; Calandra, Matteo; Mauri, Francesco

    2016-07-01

    We investigate the capability of density functional theory (DFT) to appropriately describe the spin susceptibility, χs, and the intervalley electron-phonon coupling in LixZrNCl . At low doping, LixZrNCl behaves as a two-dimensional two-valley electron gas, with parabolic bands. In such a system, χs increases with decreasing doping because of the electron-electron interaction. We show that DFT with local functionals (LDA/GGA) is not capable of reproducing this behavior. The use of exact exchange in Hartree-Fock (HF) or in DFT hybrid functionals enhances χs. HF, B3LYP, and PBE0 approaches overestimate χs, whereas the range-separated HSE06 functional leads to results similar to those obtained in the random phase approximation (RPA) applied to a two-valley two-spin electron gas. Within HF, LixZrNCl is even unstable towards a ferromagnetic state for x <0.16 . The intervalley phonons induce an imbalance in the valley occupation that can be viewed as the effect of a pseudomagnetic field. Thus, similarly to what happens for χs, the electron-phonon coupling of intervalley phonons is enhanced by the electron-electron interaction. Only hybrid DFT functionals capture such an enhancement and the HSE06 functional reproduces the RPA results presented in M. Calandra et al. [Phys. Rev. Lett. 114, 077001 (2015), 10.1103/PhysRevLett.114.077001]. These results imply that the description of the susceptibility and electron-phonon coupling with a range-separated hybrid functional would be important also in other two-dimensional weakly doped semiconductors, such as transition-metal dichalcogenides and graphene.

  9. Mobile Phone Usage and its Health Effects Among Adults in a Semi-Urban Area of Southern India

    PubMed Central

    Abraham, Sherin Billy; Kanimozhy, K.; Prasad, R. Vishnu; Singh, Zile; Purty, Anil J.

    2016-01-01

    Introduction Worldwide, mobile phone usage has been increased dramatically which could affect the health of the people. India has the second largest number of mobile phone users. However there are only few studies conducted in India to assess its effects on health. Aim To determine the prevalence and pattern of mobile phone usage and to assess the relationship between certain selected health problems and mobile phone usage among adults. Settings and Design Community-based cross-sectional study was conducted in Kottakuppam, a town panchayat in Villupuram district of Coastal Tamil Nadu, Southern India. It is a semi-urban area with a population of about 16,000. Majority of the residents are Muslim by religion and belong to different socio economic status. Materials and Methods The study was approved by the Institutional Ethics Committee. A total of 2121 study participants were interviewed by the pre-final medical students through house-to-house survey using a pretested structured questionnaire. The questionnaire included the variables such as socio demographic profile, mobile phone usage and pattern, selected health problems, perceived benefits and threats and blood pressure. Selected health problems included headache, earache, neck pain, tinnitus, painful fingers, restlessness, morning tiredness, tingling fingers, fatigue, eye symptoms, sleep disturbance and hypertension. Statistical Analysis Used Only 2054 were included for data analysis using SPSS 17 version. Proportions were calculated. Chi-square test was used to measure the p-value. The p-value < 0.05 was considered as statistically significant. Results The prevalence of mobile phone usage was 70%. Calling facility (94.2%) was used more than the SMS (67.6%). Health problems like headache, earache, tinnitus, painful fingers and restlessness etc., were found to be positively associated with mobile phone usage. There was negative association between hypertension and mobile phone usage. Conclusion The prevalence of

  10. Usage of complementary and alternative medicine among patients with chronic kidney disease on maintenance hemodialysis

    PubMed Central

    Arjuna Rao, Aravapalli S. M.; Phaneendra, D.; Pavani, Ch. Divya; Soundararajan, P.; Rani, N. Vanitha; Thennarasu, P.; Kannan, G.

    2016-01-01

    Aim: To determine the prevalence and the type of complementary and alternative medicine (CAM) use among chronic kidney disease (CKD) patients on maintenance hemodialysis (MHD). Materials and Methods: The study was conducted in 200 CKD patients who were on MHD. The patients were subjected to a validated interviewer-administered questionnaire adopted from the National Health Interview Survey Adult CAM. The knowledge on CAM and its usage by the patients were assessed based on the responses given by the patients. Results: Of the 200 patients, 52 (26%) patients were identified to be using CAM therapy. The most commonly used CAM modality by these patients was Ayurveda both alone (30.4%) and in combination with other CAM modalities (23.2%), followed by acupuncture in 17.3% patients. CAM usage was high in the age range of 50–64 years (67%). Of the CAM users, 21% of patients were from a rural area; 16.5% of patients were from upper middle class, and 24% were on dialysis for 1–4 years. There was a statistically significant association between CAM usage and age, gender, place of living, socioeconomic status, and duration of dialysis (P < 0.01). Conclusion: The present survey provides the data on the usage of CAM among dialysis patients and adds to the increasing evidence about CAM use. Because many products are at risk to either accumulate or cause interactions with medication, a better education on the risks and benefits of the CAM therapy by the health care providers to the end stage renal disease patients is needed. PMID:26957870

  11. Optical coupling

    NASA Astrophysics Data System (ADS)

    Bock, J. J.; Gundersen, J.; Lee, A. T.; Richards, P. L.; Wollack, E.

    2009-03-01

    This paper describes contributions to the CMBpol Technology Study Workshop concerning optical coupling structures. These are structures in or near the focal plane which convert the free space wave to a superconducting microstrip on a SI wafer, or to the waveguide input to a HEMT receiver. In addition to an introduction and conclusions by the editor, this paper includes independent contributions by Bock on 'Planar Antenna-Coupled Bolometers for CMB Polarimetry', by Gunderson and Wollack on 'Millimeter-Wave Platlet Feeds', and by Lee on 'Multi-band Dual-Polarization Lens-coupled Planar Antennas for Bolometric CMB polarimetry.'

  12. Smartphone usage among ROTU and its relationship towards study performance

    NASA Astrophysics Data System (ADS)

    Redzuan, Muhammad Fazrul Ilahi Mohd; Roslan, Mohamad Amri; Rahman, Rosshairy Abd

    2015-12-01

    Reserve Officer Training Unit (ROTU) is a cooperation program between the Ministry of Defense and the Ministry of Higher Education for undergraduate students in public university. ROTU is known for its tight training schedule which might lead to limited learning time. The usage of smartphone with various applications might assist them in their learning activities. Therefore, this study aims to discover the rate of smartphone usage among ROTU and then analyze the relationship of smartphone usage towards their study performance. The result shows that most of the ROTU students use smartphone for five to eight hours a day. No significant correlation between relationship of smartphone and study performance of ROTU students with very small positive relationship was recorded. The result reflects that the frequent use of smartphone applications among ROTU students could not significantly help them in the study. However, further study need to be carried out since this paper does not specifically focus on each type of application. Therefore, for future research, usage rate for each application is also needed to be discovered so that the usage impact for ROTU study performance on each application can be seen clearly.

  13. Mobile usage and sleep patterns among medical students.

    PubMed

    Yogesh, Saxena; Abha, Shrivastava; Priyanka, Singh

    2014-01-01

    Exposure of humans to radio frequency electromagnetic field (EMF) both during receiving and transmitting the signals has amplified public and scientific debate about possible adverse effects on human health. The study was designed with the objective of assessing the extent of mobile phone use amongst medical students and finding correlation if any between the hours of usage of mobile to sleep pattern and quality. hundred medical students grouped as cases (n = 57) (> 2 hours/day of mobile usage) and control (n = 43) (≤ 2 hours/day of mobile usage) were examined for their sleep quality & pattern by Pittsburg sleep Quality Index (PSQI). Differences between groups were examined with the Mann Whitney "U" test for proportions (Quantitative values) and with Student't' test for continuous variables. The association of variables was analyzed by Spearman Rank's correlation. Probability was set at < 0.05 as significant. Sleep disturbance, latency and day dysfunction was more in cases especially females. A significant association of hours of usage and sleep indices were observed in both genders (males r = 0.25; p = 0.04, females r = 0.31; p = 0.009). Evening usage of mobile phone in cases showed a statistically significant negative association (-0.606; p = 0.042) with Sleep quality (higher PSQI means sleep deprivation). Students using mobile for > 2 hours/day may cause sleep deprivation and day sleepiness affecting cognitive and learning abilities of medical students. PMID:25464686

  14. Mobile usage and sleep patterns among medical students.

    PubMed

    Yogesh, Saxena; Abha, Shrivastava; Priyanka, Singh

    2014-01-01

    Exposure of humans to radio frequency electromagnetic field (EMF) both during receiving and transmitting the signals has amplified public and scientific debate about possible adverse effects on human health. The study was designed with the objective of assessing the extent of mobile phone use amongst medical students and finding correlation if any between the hours of usage of mobile to sleep pattern and quality. hundred medical students grouped as cases (n = 57) (> 2 hours/day of mobile usage) and control (n = 43) (≤ 2 hours/day of mobile usage) were examined for their sleep quality & pattern by Pittsburg sleep Quality Index (PSQI). Differences between groups were examined with the Mann Whitney "U" test for proportions (Quantitative values) and with Student't' test for continuous variables. The association of variables was analyzed by Spearman Rank's correlation. Probability was set at < 0.05 as significant. Sleep disturbance, latency and day dysfunction was more in cases especially females. A significant association of hours of usage and sleep indices were observed in both genders (males r = 0.25; p = 0.04, females r = 0.31; p = 0.009). Evening usage of mobile phone in cases showed a statistically significant negative association (-0.606; p = 0.042) with Sleep quality (higher PSQI means sleep deprivation). Students using mobile for > 2 hours/day may cause sleep deprivation and day sleepiness affecting cognitive and learning abilities of medical students. PMID:25508317

  15. MESUR: USAGE-BASED METRICS OF SCHOLARLY IMPACT

    SciTech Connect

    BOLLEN, JOHAN; RODRIGUEZ, MARKO A.; VAN DE SOMPEL, HERBERT

    2007-01-30

    The evaluation of scholarly communication items is now largely a matter of expert opinion or metrics derived from citation data. Both approaches can fail to take into account the myriad of factors that shape scholarly impact. Usage data has emerged as a promising complement to existing methods o fassessment but the formal groundwork to reliably and validly apply usage-based metrics of schlolarly impact is lacking. The Andrew W. Mellon Foundation funded MESUR project constitutes a systematic effort to define, validate and cross-validate a range of usage-based metrics of schlolarly impact by creating a semantic model of the scholarly communication process. The constructed model will serve as the basis of a creating a large-scale semantic network that seamlessly relates citation, bibliographic and usage data from a variety of sources. A subsequent program that uses the established semantic network as a reference data set will determine the characteristics and semantics of a variety of usage-based metrics of schlolarly impact. This paper outlines the architecture and methodology adopted by the MESUR project and its future direction.

  16. Development of an extraction method based on new porous organogel materials coupled with liquid chromatography-mass spectrometry for the rapid quantification of bisphenol A in urine.

    PubMed

    ter Halle, Alexandra; Claparols, Catherine; Garrigues, Jean Christophe; Franceschi-Messant, Sophie; Perez, Emile

    2015-10-01

    A new method based on the use of porous organogel materials in combination with liquid chromatography-tandem mass spectrometry (LC-MS-MS) was assessed for the quantification of trace contaminants in complex matrices. As a demonstration of the use of these new materials, the contaminant chosen as a model was bisphenol A (BPA) and its extraction was investigated in urine. Organogel materials consist of an organic solvent immobilized by an organogelator. The composition of the organogel materials was optimized in terms of extraction efficiency and compatibility with LC-MS-MS. Porosity was introduced into the organogel by means of the particulate leaching method using sugar crystals. This new absorbing material is simple to use; the extraction method is reduced to a few steps. The originality of the method lies in the complete dissolution of the material for analysis by LC-MS-MS. The matrix effect of the organogel components was studied and was found to be minimal in atmospheric-pressure chemical ionization (APCI) compared to electrospray ionization (ESI) in negative mode. The influence of matrix components on the extraction was investigated by working with different media (acidified water, synthetic urine, horse urine and human urine). The partition coefficient was not affected within the margin of error (±0.1). After optimization, bisphenol A recoveries from urine samples reached 80%. The actual concentration factor was 10. The relative standard deviation (RSD, n=6) for the extraction and determination of BPA in horse urine spiked at 10ngmL(-1) was 9%. Tests with spiked human urine showed that the extraction performances were the same as with the solutions tested previously. The use of porous organogel allowed a fast, simple, sensitive, robust, green method to be developed for the determination of trace contaminants in complex matrices. PMID:26342874

  17. Dissolution and nanoparticle generation behavior of Be-associated materials in synthetic lung fluid using inductively coupled plasma mass spectroscopy and flow field-flow fractionation.

    PubMed

    Huang, Wenjie; Fernandez, Diego; Rudd, Abigail; Johnson, William P; Deubner, David; Sabey, Philip; Storrs, Jason; Larsen, Rod

    2011-07-01

    Various Be-containing micro-particle suspensions were equilibrated with simulated lung fluid (SLF) to examine their dissolution behavior as well as the potential generation of nanoparticles. The motivation for this study was to explore the relationship between dissolution/particle generation behaviors of Be-containing materials relevant to Be-ore processing, and their epidemiologically indicated inhalation toxicities. Limited data suggest that BeO is associated with higher rates of beryllium sensitization (BS) and chronic beryllium disease (CBD) relative to the other five relevant materials studied: bertrandite-containing ore, beryl-containing ore, frit (a processing intermediate), Be(OH)₂ (a processing intermediate), and silica (control). These materials were equilibrated with SLF at two pH values (4.5 and 7.2) to reflect inter- and intra-cellular environments in lung tissue. Concentrations of Be, Al, and Si in SLF increased linearly during the first 20 days of equilibration, and then rose slowly, or in some cases reached a maximum, and subsequently decreased. Relative to the other materials, BeO produced relatively low Be concentration in solution at pH 7.2; and relatively high Be concentration in solution at pH 4.5 during the first 20 days of equilibration. For both pH values, however, the Be concentration in SLF normalized to Be content of the material was lowest for BeO, demonstrating that BeO was distinct among the four other Be-containing materials in terms of its persistence as a source of Be to the SLF solution. Following 149 days of equilibration, the SLF solutions were fractionated using flow-field flow fractionation (FlFFF) with detection via ICP-MS. For all materials, nanoparticles (which were formed during equilibration) were dominantly distributed in the 10-100 nm size range. Notably, BeO produced the least nanoparticle-associated Be mass (other than silica) at both pH values. Furthermore, BeO produced the highest Be concentrations in the size

  18. Dietary supplement usage by patients with cancer undergoing chemotherapy: does prognosis or cancer symptoms predict usage?

    PubMed

    Bardia, Aditya; Greeno, Edward; Bauer, Brent A

    2007-04-01

    Any interactions between chemotherapeutic drugs and dietary supplements (DS) are a concern for oncologists. This study sought to obtain pilot data about the prevalence of consumption of DS (which include vitamin/mineral supplements [VS] and herbal supplements [HS]) among patients undergoing chemotherapy and to assess the relationship between DS consumption and both cancer prognosis and secondary cancer symptoms. In this pilot study, data on demographics, DS usage, presence of secondary cancer symptoms, and cancer diagnosis and stage were collected on 100 consecutive patients with gastrointestinal cancer and 40 with breast cancer who were receiving active chemotherapy from April 2004 to July 2004. Overall prevalence of DS consumption was 52.52% +/- 8.3% (VS,48.2% +/- 8.31%; HS, 23.74% +/- 7.07%). Of HS users, 42.42% +/- 16.86% used multiple HS. Factors significantly associated with higher consumption of HS were female gender and presence of metastasis, fatigue, and cancer pain. No significant associations between consumption of DS or HS and age, cancer type, presence of pain, sleep problems, or sexual problems were seen. Approximately half of the patients undergoing chemotherapy in this pilot survey were using DS, including HS--which heralds the potential for drug-supplement interactions and warrants caution. Consumption of HS was greater among people having a higher cancer stage and symptoms such as fatigue or cancer pain; patients in these subgroups probably should be screened actively for DS use. Further studies are needed to confirm these results. PMID:17500507

  19. A highly active recyclable gold-graphene nanocomposite material for oxidative esterification and Suzuki cross-coupling reactions in green pathway.

    PubMed

    Mondal, Paramita; Salam, Noor; Mondal, Avijit; Ghosh, Kajari; Tuhina, K; Islam, Sk Manirul

    2015-12-01

    A graphene based composite with gold nanoparticles has been synthesized via a simple chemical route and the structure and compositions of nanocomposite has been characterized. The catalyst was found to be remarkably stable and active for the oxidative esterification of alcohols under present reaction conditions using molecular oxygen as green oxidant and Suzuki cross-coupling reactions between aryl halides and phenylboronic acids using environmentally friendly water as solvent. The versatility of both the protocols was demonstrated by taking a number of substrates. This protocol offers several advantages like high yields, clean reactions, recyclability of the catalyst, reaction in water and use of green oxidant. This study suggests graphene, as an economical substitute for carbon nanotubes, could act as a prominent support in heterogeneous catalysis. PMID:26275502

  20. Determination of rare earth elements in human hair and wheat flour reference materials by inductively coupled plasma mass spectrometry with dry ashing and microwave digestion

    NASA Astrophysics Data System (ADS)

    Ming, Yin; Bing, Li

    1998-09-01

    A method was developed for the determination of all rare earth elements (REEs) at sub ng g -1 levels in human hair (GBW 09101, SRM, Republic of China) and wheat flour (GBW 08503, SRM, Republic of China) by Inductively coupled plasma mass spectrometry (ICP-MS). The values obtained by dry ashing and microwave oven digestion procedures were compared with those obtained by traditional open vessel acid digestion method. The validity of the analytical procedure was examined by analyzing spiked samples and two vegetables (GBW 07603 and GBW 07605, SRMs, Republic of China). The results are satisfactory. The detection limits for 14 REEs ranged from 0.0039 to 0.0003 ng cm -3 in solution and the quantification limits ranged from 0.16 to 0.01 ng g -1 in solid sample. The precision for most REEs were less than 10% RSD.

  1. Study on online community user motif using web usage mining

    NASA Astrophysics Data System (ADS)

    Alphy, Meera; Sharma, Ajay

    2016-04-01

    The Web usage mining is the application of data mining, which is used to extract useful information from the online community. The World Wide Web contains at least 4.73 billion pages according to Indexed Web and it contains at least 228.52 million pages according Dutch Indexed web on 6th august 2015, Thursday. It’s difficult to get needed data from these billions of web pages in World Wide Web. Here is the importance of web usage mining. Personalizing the search engine helps the web user to identify the most used data in an easy way. It reduces the time consumption; automatic site search and automatic restore the useful sites. This study represents the old techniques to latest techniques used in pattern discovery and analysis in web usage mining from 1996 to 2015. Analyzing user motif helps in the improvement of business, e-commerce, personalisation and improvement of websites.

  2. Mining Software Usage with the Automatic Library Tracking Database (ALTD)

    SciTech Connect

    Hadri, Bilel; Fahey, Mark R

    2013-01-01

    Tracking software usage is important for HPC centers, computer vendors, code developers and funding agencies to provide more efficient and targeted software support, and to forecast needs and guide HPC software effort towards the Exascale era. However, accurately tracking software usage on HPC systems has been a challenging task. In this paper, we present a tool called Automatic Library Tracking Database (ALTD) that has been developed and put in production on several Cray systems. The ALTD infrastructure prototype automatically and transparently stores information about libraries linked into an application at compilation time and also the executables launched in a batch job. We will illustrate the usage of libraries, compilers and third party software applications on a system managed by the National Institute for Computational Sciences.

  3. Commercial Building Tenant Energy Usage Aggregation and Privacy

    SciTech Connect

    Livingston, Olga V.; Pulsipher, Trenton C.; Anderson, David M.; Wang, Na

    2014-10-31

    A growing number of building owners are benchmarking their building energy use. This requires the building owner to acquire monthly whole-building energy usage information, which can be challenging for buildings in which individual tenants have their own utility meters and accounts with the utility. Some utilities and utility regulators have turned to aggregation of customer energy use data (CEUD) as a way to give building owners whole-building energy usage data while protecting customer privacy. Meter profile aggregation adds a layer of protection that decreases the risk of revealing CEUD as the number of meters aggregated increases. The report statistically characterizes the similarity between individual energy usage patterns and whole-building totals at various levels of meter aggregation.

  4. Energy intensity, electricity consumption, and advanced manufacturing-technology usage

    SciTech Connect

    Doms, M.E.; Dunne, T.

    1995-07-01

    This article reports on the relationship between the usage of advanced manufacturing technologies (AMTs) and energy consumption patterns in manufacturing plants. Using data from the Survey of Manufacturing Technology and the 1987 Census of Manufactures, we model the energy intensity and the electricity intensity of plants as functions of AMT usage and plant age. The main findings are that plants that utilize AMTs are less-energy intensive than plants not using AMTs, but consume proportionately more electricity as a fuel source. Additionally, older plants are generally more energy intensive and rely on fossil fuels to a greater extent than younger plants. 25 refs., 3 tabs.

  5. A backtranslation method based on codon usage strategy.

    PubMed Central

    Pesole, G; Attimonelli, M; Liuni, S

    1988-01-01

    This study describes a method for the backtranslation of an aminoacidic sequence, an extremely useful tool for various experimental approaches. It involves two computer programs CLUSTER and BACKTR written in Fortran 77 running on a VAX/VMS computer. CLUSTER generates a reliable codon usage table through a cluster analysis, based on a chi 2-like distance between the sequences. BACKTR produces backtranslated sequences according to different options when use is made of the codon usage table obtained in addition to selecting the least ambiguous potential oligonucleotide probes within an aminoacidic sequence. The method was tested by applying it to 158 yeast genes. PMID:3281142

  6. Critical materials - A new dimension

    NASA Astrophysics Data System (ADS)

    Siegel, M. A.

    1981-03-01

    An overview of raw material availability and utilization is presented. The specific requirements and objectives of the major industrial groups such as the chemical processing, automotive, aerospace, and energy industries are discussed with attention to the increasing influence of raw materials on product cost. Scrap recycling as well as new material systems which offer the potential for significant reductions in critical material usage are also considered.

  7. Coupled moderator neutronics

    SciTech Connect

    Russell, G.J.; Pitcher, E.J.; Ferguson, P.D.

    1995-12-01

    Optimizing the neutronic performance of a coupled-moderator system for a Long-Pulse Spallation Source is a new and challenging area for the spallation target-system designer. For optimal performance of a neutron source, it is essential to have good communication with instrument scientists to obtain proper design criteria and continued interaction with mechanical, thermal-hydraulic, and materials engineers to attain a practical design. A good comprehension of the basics of coupled-moderator neutronics will aid in the proper design of a target system for a Long-Pulse Spallation Source.

  8. High temperature pressure coupled ultrasonic waveguide

    SciTech Connect

    Caines, M.J.

    1983-07-12

    A pressure coupled ultrasonic waveguide is provided to which one end may be attached a transducer and at the other end a high temperature material for continuous ultrasonic testing of the material. The ultrasonic signal is coupled from the waveguide into the material through a thin, dry copper foil.

  9. High temperature pressure coupled ultrasonic waveguide

    DOEpatents

    Caines, Michael J.

    1983-01-01

    A pressure coupled ultrasonic waveguide is provided to which one end may be attached a transducer and at the other end a high temperature material for continuous ultrasonic testing of the material. The ultrasonic signal is coupled from the waveguide into the material through a thin, dry copper foil.

  10. Robust method for the analysis of phytochelatins in rice by high-performance liquid chromatography coupled with electrospray tandem mass spectrometry based on polymeric column materials.

    PubMed

    Yu, Shasha; Bian, Yingfang; Zhou, Rong; Mou, Renxiang; Chen, Mingxue; Cao, Zhaoyun

    2015-12-01

    A sensitive and robust high-performance liquid chromatography coupled with electrospray tandem mass spectrometry method for the identification and quantification of glutathione and phytochelatins from rice was developed. Homogenized samples were extracted with water containing 100 mM dithiothreitol, and solid-phase extraction using polymer anion exchange resin was employed for sample purification. Chromatography was performed on a polymeric column with acetonitrile and water containing 0.1% formic acid as the mobile phase at the flow rate of 300 μL/min. The limit of quantitation was 6-100 nM. This assay showed excellent linearity for both glutathione and phytochelatins over physiological normal ranges, with correlation coefficients (r) > 0.9976. Recoveries for four biothiols were within the range of 76-118%, within relative standard deviations less than 15%. The intraday precision (n = 7) was 2.1-13.3%, and the interday precision over 15 days was 4.3-15.2%. The optimized method was applied to analyze tissue samples from rice grown using nutrient solutions with three different cadmium concentrations (0, 50, and 100 μM). With increasing cadmium concentrations, the content of phytochelatin 2 and phytochelatin 3 in rice roots increased, in contrast to most phytochelatins, and the content of glutathione in rice stems and roots decreased significantly. PMID:26541262

  11. Prosthesis coupling

    NASA Technical Reports Server (NTRS)

    Reswick, J. B.; Mooney, V.; Bright, C. W.; Owens, L. J. (Inventor)

    1979-01-01

    A coupling for use in an apparatus for connecting a prosthesis to the bone of a stump of an amputated limb is described which permits a bio-compatible carbon sleeve forming a part of the prosthesis connector to float so as to prevent disturbing the skin seal around the carbon sleeve. The coupling includes a flexible member interposed between a socket that is inserted within an intermedullary cavity of the bone and the sleeve. A lock pin is carried by the prosthesis and has a stem portion which is adapted to be coaxially disposed and slideably within the tubular female socket for securing the prosthesis to the stump. The skin around the percutaneous carbon sleeve is able to move as a result of the flexing coupling so as to reduce stresses caused by changes in the stump shape and/or movement between the bone and the flesh portion of the stump.

  12. FLEXIBLE COUPLING

    DOEpatents

    Babelay, E.F.

    1962-02-13

    A flexible shaft coupling for operation at speeds in excess of 14,000 rpm is designed which requires no lubrication. A driving sleeve member and a driven sleeve member are placed in concentric spaced relationship. A torque force is transmitted to the driven member from the driving member through a plurality of nylon balls symmetrically disposed between the spaced sleeves. The balls extend into races and recesses within the respective sleeve members. The sleeve members have a suitable clearance therebetween and the balls have a suitable radial clearance during operation of the coupling to provide a relatively loose coupling. These clearances accommodate for both parallel and/or angular misalignments and avoid metal-tometal contact between the sleeve members during operation. Thus, no lubrication is needed, and a minimum of vibrations is transmitted between the sleeve members. (AEC)

  13. Educating Students about the Risks of Excessive Videogame Usage.

    ERIC Educational Resources Information Center

    Kasper, Deirdre; Welsh, Sarah; Chambliss, Catherine

    The relationship between videogame usage, active exercise, television viewing, and measures of blood pressure is explored. Videogame participation, especially playing sports or action games, simulates involvement in aggressive situations. This may activate the fight or flight response in players. This response has been associated with blood…

  14. Investigating Students' Usage and Acceptance of Electronic Books

    ERIC Educational Resources Information Center

    Sieche, Susan; Krey, Birte; Bastiaens, Theo

    2013-01-01

    The purpose of this study is to investigate students' usage and acceptance of electronic books. Factors correlating with students' attitude towards e-books were examined using the Technology Acceptance Model (Davis, Bagozzi, & Warshaw 1989). A questionnaire was administered online for students at University of Hagen. Results indicate…

  15. Issues of ICT Usage among Malaysian Secondary School English Teachers

    ERIC Educational Resources Information Center

    Raman, Arumugam; Mohamed, Abdul Halim

    2013-01-01

    This study explored on perception, usage and obstacles of using ICT in teaching English Language among secondary school English teachers. The advancement of technology has given a space for teachers to boost teaching and learning of English language in secondary schools. It is believed that integration of ICT could enhance quality of teaching and…

  16. 47 CFR 5.402 - Eligibility and usage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... licenses are for testing in clinical trials medical devices that use RF wireless technology for diagnosis... Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EXPERIMENTAL RADIO SERVICE Medical Testing Experimental Radio Licenses § 5.402 Eligibility and usage. (a) Eligibility for medical testing licenses is limited...

  17. 47 CFR 5.402 - Eligibility and usage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... licenses are for testing in clinical trials medical devices that use RF wireless technology for diagnosis... Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EXPERIMENTAL RADIO SERVICE Medical Testing Experimental Radio Licenses § 5.402 Eligibility and usage. (a) Eligibility for medical testing licenses is limited...

  18. Fuel bundle design for enhanced usage of plutonium fuel

    DOEpatents

    Reese, Anthony P.; Stachowski, Russell E.

    1995-01-01

    A nuclear fuel bundle includes a square array of fuel rods each having a concentration of enriched uranium and plutonium. Each rod of an interior array of the rods also has a concentration of gadolinium. The interior array of rods is surrounded by an exterior array of rods void of gadolinium. By this design, usage of plutonium in the nuclear reactor is enhanced.

  19. Investigating Learner Preparedness for and Usage Patterns of Mobile Learning

    ERIC Educational Resources Information Center

    Stockwell, Glenn

    2008-01-01

    While the use of mobile devices for language learning has sparked the interest of an increasing number of researchers in recent years (e.g., Aizawa & Kiernan, 2003; Thornton & Houser, 2005), our knowledge of learners' preferences for the mobile platform and their usage patterns remains limited. Are learners prepared to use mobile phones for…

  20. Geography Teachers' Usage of the Internet for Education Purposes

    ERIC Educational Resources Information Center

    Sezer, Adem

    2010-01-01

    The purpose of this study is to determine geography teachers' use of the Internet for education purposes and the extent to which Turkish Internet sites can fulfill the needs and requirements of geography teachers' Internet usage. Research is carried out using the screening method. Data were collected by means of a measurement tool that was…

  1. Usage-Based Collection Evaluation with a Curricular Focus

    ERIC Educational Resources Information Center

    Kohn, Karen C.

    2013-01-01

    Systematic evaluation of a library's collection can be a useful tool for collection development. After reviewing three evaluation methods and their usefulness for our small academic library, I undertook a usage-based evaluation, focusing on narrow segments of our collection that served specific undergraduate courses. For each section, I collected…

  2. The Relationship between Social Cohesion and Computer-Internet Usage

    ERIC Educational Resources Information Center

    Balkan, Emre; Adalier, Ahmet

    2011-01-01

    The aim of this study is to analyze the relationship between social cohesion and computer-internet usage among university students. The research was conducted among university students in North Cyprus. The sample for the research consists of 38.8% (n=80) female, 61.2 % (n=126) male, 206 university students by using the criterion sampling method.…

  3. A Survey of ICT Usage across English Secondary Schools

    ERIC Educational Resources Information Center

    Savage, Jonathan

    2010-01-01

    The use of information and communication technologies (ICT) is a statutory component of the Key Stages 2 and 3 National Curricula in the UK. This research presents findings from a national survey of the availability and usage of ICT in music classrooms within English secondary schools. It also examined a range of issues related to the training and…

  4. Usage and User Experience of Communication before and during Rendezvous

    ERIC Educational Resources Information Center

    Colbert, Martin

    2005-01-01

    This paper reports a field evaluation of the mobile phone as a "package" of device and services. The evaluation compares 44 university students' usage and user experience of communication before and during rendezvous. During a rendezvous (en route), students rated many aspects of the experience of phone use less favourably than before a rendezvous…

  5. A Dynamic Usage Based Perspective on L2 Writing

    ERIC Educational Resources Information Center

    Verspoor, Marjolijn; Schmid, Monika S.; Xu, Xiaoyan

    2012-01-01

    The goal of this study was to explore the contribution that a dynamic usage based (DUB) perspective can bring to the establishment of objective measures to assess L2 learners' written texts and at the same time to gain insight into the dynamic process of language development. Four hundred and thirty seven texts written by Dutch learners of English…

  6. Canadian Community College Computer Usage Survey, May 1983.

    ERIC Educational Resources Information Center

    Gee, Michael Dennis

    This survey was conducted to provide information on the level of computer usage in Canadian community colleges. A 19-question form was mailed to the deans of instruction in 175 Canadian public community colleges identified as such by Statistics Canada. Of these, 111 colleges returned their surveys (a 63% response rate), and the results were…

  7. Assessing Usage and Maximizing Finance Lab Impact: A Case Exploration

    ERIC Educational Resources Information Center

    Noguera, Magdy; Budden, Michael Craig; Silva, Alberto

    2011-01-01

    This paper reports the results of a survey conducted to assess students' usage and perceptions of a finance lab. Finance labs differ from simple computer labs as they typically contain data boards, streaming market quotes, terminals and software that allow for real-time financial analyses. Despite the fact that such labs represent significant and…

  8. Medical Information Availability and Usage in South Texas. Final Report.

    ERIC Educational Resources Information Center

    Bowden, Virginia M.; And Others

    This project examined the impact of the University of Texas Health Science Center's Circuit Library Health Information Network (CLHIN) on availability and usage of medical information to health professionals and the effect of the promotion of online services, GRATEFUL MED and MEDLINE (flat rate). The project included a survey of physicians,…

  9. Lutheran School Teachers' Instructional Usage of the Interactive Whiteboard

    ERIC Educational Resources Information Center

    Powers, Jillian R.

    2014-01-01

    The purpose of this mixed methods study was twofold. First, the study assessed whether Davis' (1989) Technology Acceptance Model (TAM) was useful in predicting instructional usage of the interactive whiteboard (IWB), as reported by K-8 teachers. Second, the study set out to understand what motivated those teachers to use the IWB for classroom…

  10. Electronic Book Usage: A Survey at the University of Denver

    ERIC Educational Resources Information Center

    Levine-Clark, Michael

    2006-01-01

    In the spring of 2005, the University of Denver's Penrose Library conducted a survey of its users to determine their degree of awareness of electronic books, how and why they use them, and their level of satisfaction with the format. It is clear from vendor-supplied usage statistics that electronic books are used, but it is not clear how or why…

  11. Anabolic steroid usage in athletics: facts, fiction, and public relations.

    PubMed

    Berning, Joseph M; Adams, Kent J; Stamford, Bryant A

    2004-11-01

    Anecdotal evidence suggests the widespread usage of anabolic steroids among athletes (20-90%), particularly at the professional and elite amateur levels. In contrast, scientific studies indicate that usage is rare and no higher than 6%. Conclusions from scientific studies suggest that anabolic steroid usage declines progressively from high school to college and beyond; however, anecdotal evidence claims the opposite trend. In this clash between "hard" scientific data vs. "soft" anecdotal information, it is natural that professionals would gravitate toward scientifically based conclusions. However, in the case of anabolic steroids (a stigmatized and illegal substance), should word-of-mouth testimony from individuals closest to the issues--those who have participated in and coached sports, those who have served as drug-testing overseers, and journalists who relentlessly track leads and verify sources--be set aside as irrelevant? Not if a complete picture is to emerge. In this review, hard scientific evidence is placed on the table side-by-side with soft anecdotal evidence, without weighting or bias. The purpose is to allow the opportunity for each to illuminate the other and, in so doing, potentially bring us a step closer to determining the true extent of anabolic steroid usage in athletics. PMID:15574100

  12. Gene classification using codon usage and support vector machines.

    PubMed

    Ma, Jianmin; Nguyen, Minh N; Rajapakse, Jagath C

    2009-01-01

    A novel approach for gene classification, which adopts codon usage bias as input feature vector for classification by support vector machines (SVM) is proposed. The DNA sequence is first converted to a 59-dimensional feature vector where each element corresponds to the relative synonymous usage frequency of a codon. As the input to the classifier is independent of sequence length and variance, our approach is useful when the sequences to be classified are of different lengths, a condition that homology-based methods tend to fail. The method is demonstrated by using 1,841 Human Leukocyte Antigen (HLA) sequences which are classified into two major classes: HLA-I and HLA-II; each major class is further subdivided into sub-groups of HLA-I and HLA-II molecules. Using codon usage frequencies, binary SVM achieved accuracy rate of 99.3% for HLA major class classification and multi-class SVM achieved accuracy rates of 99.73% and 98.38% for sub-class classification of HLA-I and HLA-II molecules, respectively. The results show that gene classification based on codon usage bias is consistent with the molecular structures and biological functions of HLA molecules. PMID:19179707

  13. Social Media Usage: Examination of Influencers and Effects

    ERIC Educational Resources Information Center

    Brooks, Stoney L.

    2013-01-01

    This dissertation is concerned with investigating topics surrounding the phenomenon of social media usage. Essay One draws from the technology acceptance literature by utilizing concepts from the Technology Acceptance Model (TAM), the Unified Theory of Acceptance and Use of Technology (UTAUT), and the model of hedonic technology acceptance. The…

  14. Consumer-Centered Extension Education Website Increases Usage

    ERIC Educational Resources Information Center

    Franics, Sarah L.; Martin, Peggy; Taylor, Kristin

    2012-01-01

    Concern about young families' ability to cope with rising food prices resulted in creating Spend Smart. Eat Smart (SSES), a website focused on budget-friendly nutrition information for limited resource audiences (LRA). SSES was redesigned using LRAs needs and preferences to increase use by LRAs. SSES usage increased after it was revised to…

  15. Multimedia Usage among Islamic Education Lecturers at Higher Education Institution

    ERIC Educational Resources Information Center

    Hamzah, Mohd Isa; Rinaldi; Razak, Khadijah Abdul

    2014-01-01

    This study aims to examine the level of multimedia usage among Islamic education lecturers at higher education institutions in West Sumatera, Indonesia. The participants were chosen from three types of higher institutions by using stratified random sampling. The data was collected from 250 students using questionnaires. The findings showed that…

  16. Pre Service Teachers' Usage of Dynamic Mathematics Software

    ERIC Educational Resources Information Center

    Bulut, Mehmet; Bulut, Neslihan

    2011-01-01

    Aim of this study is about mathematics education and dynamic mathematics software. Dynamic mathematics software provides new opportunities for using both computer algebra system and dynamic geometry software. GeoGebra selected as dynamic mathematics software in this research. In this study, it is investigated that what is the usage of pre service…

  17. Evaluating overall usage of a digital health sciences library.

    PubMed Central

    D'Alessandro, M P; D'Alessandro, D M; Galvin, J R; Erkonen, W E

    1998-01-01

    BACKGROUND: Digital health sciences library (DHSL) evaluation involves studying the usage of the DHSL by individuals as well as populations. The purpose of this study was to evaluate trends in overall usage of a DHSL as part of a process of continuous quality improvement in order to learn how to enhance a DHSL in order to meet its users' needs better. METHODS: Web server log file analysis was performed on a prototype DHSL, the Virtual Hospital, using two log file analysis programs on data from the month of February over four consecutive years, 1995 to 1998. RESULTS: Overall DHSL usage increased between 1995 and 1997 and leveled off in 1998. Fifteen percent of usage came from countries outside the United States. A broad spectrum of medical information for health care providers and patients was accessed and centered around specialty medical information. CONCLUSIONS: To be of optimal assistance to users, DHSLs should (1) contain a broad base of information on common and uncommon medical problems, (2) accommodate the needs of the significant percentage of users that are international through content translation and mirroring, and (3) ensure they are indexed and catalogued in the major Web search engines and Web general and medical indices so they can be easily found by users. PMID:9803306

  18. Teaching Perspectives and Usage of Journal Writing by Clinical Faculty

    ERIC Educational Resources Information Center

    Alschuler, Mari L.

    2012-01-01

    The purpose of this study was to investigate the associations between teaching perspectives (TPs), faculty usage and perceptions of reflective journaling (RJ), and demographic characteristics among clinical faculty in nursing, social work, and counseling. A combination of causal-comparative and correlational designs was utilized, with stratified…

  19. Negative Consequences of Undergraduate Alcohol Usage: A Multivariate Gender Comparison.

    ERIC Educational Resources Information Center

    Robinson, Leonald D.

    This study examined whether female undergraduate students who share with male undergraduates similar demographics, perceptions, and alcohol use locations, also share similar alcohol usage patterns, negative consequences, and predictors for both. Secondary analysis was conducted using 1992 and 1993 U.S. Department of Education Core Survey data…

  20. Developing a Scale on the Usage of Learner Control Strategy

    ERIC Educational Resources Information Center

    Kutlu, M. Oguz

    2012-01-01

    The aim of this study was to develop a Likert-like scale in order to measure teachers' usage level of learner control strategy. This study was carried out with 219 State primary school teachers who were class teachers, Turkish teachers, English teachers, Mathematics teachers, Science teachers, Social Sciences teachers, Religion and Moral teachers…

  1. Accelerated Peer-Review Journal Usage Technique for Undergraduates

    ERIC Educational Resources Information Center

    Wallace, J. D.

    2008-01-01

    The internet has given undergraduate students ever-increasing access to academic journals via search engines and online databases. However, students typically do not have the ability to use these journals effectively. This often poses a dilemma for instructors. The accelerated peer-review journal usage (APJU) technique provides a way for…

  2. Characterization and usage of sexed semen from US field data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives were to characterize sexed semen available and its usage from US field data. This included investigating active Holstein proven bulls with sexed semen available, as well as percentages and frequencies of sexed semen matings for heifers and cows. Herds were also characterized for the...

  3. The Validity and Reliability of the Problematic Internet Usage Scale

    ERIC Educational Resources Information Center

    Ceyhan, Esra; Ceyhan, Aydogan Aykut; Gurcan, Aysen

    2007-01-01

    In this research, it was aimed to develop an instrument for determining problematic internet usage of university students. Factorial structure of the data collected from 1658 university students revealed three factors. Of these, the first factor is called negative consequences of the internet and accounted for 25.36% of the variance, the second…

  4. The Survey of English Usage: Past, Present--and Future.

    ERIC Educational Resources Information Center

    Ilson, Robert

    1982-01-01

    The 1959 Survey of English Usage has provided researchers and teachers with a corpus of spoken, manuscript, and printed Standard British English. New uses have been found for the survey's resources in recent years, and the spoken part is more widely available in book and computer tape form. (MSE)

  5. Two Studies Examining Subconscious Cognitive Processing in Collaboration Technology Usage

    ERIC Educational Resources Information Center

    Wells, Taylor Michael

    2012-01-01

    In this dissertation, I investigate how the usage of collaboration technologies consciously and subconsciously affects both communicators and how they communicate. I present two related studies examining different facets of how the use of collaboration technologies such as email and voicemail influence affective processing in the communicator and…

  6. Consumer Issues: Credit Usage, Money Management, and Bankruptcy.

    ERIC Educational Resources Information Center

    Allen, Judy L.

    During the past 10 years, consumers have experienced a substantial growth in credit and an unprecedented increase in the rate of inflation. As increases in credit usage continue to outpace increases in real income and as savings rates decline, consumers are increasingly likely to suffer financial problems and are increasingly in need of money…

  7. Analysis of Correlated Coupling of Monte Carlo Forward and Adjoint Histories

    SciTech Connect

    Ueki, Taro; Hoogenboom, J.E.; Kloosterman, J. L.

    2001-02-15

    In Monte Carlo correlated coupling, forward and adjoint particle histories are initiated in exactly opposite directions at an arbitrarily placed surface between a physical source and a physical detector. It is shown that this coupling calculation can become more efficient than standard forward calculations. In many cases, the basic form of correlated coupling is less efficient than standard forward calculations. This inherent inefficiency can be overcome by applying a black absorber perturbation to either the forward or the adjoint problem and by processing the product of batch averages as one statistical entity. The usage of the black absorber is based on the invariance of the response flow integral with a material perturbation in either the physical detector side volume in the forward problem or the physical source side volume in the adjoint problem. The batch-average product processing makes use of a quadratic increase of the nonzero coupled-score probability. All the developments have been done in such a way that improved efficiency schemes available in widely distributed Monte Carlo codes can be applied to both the forward and adjoint simulations. Also, the physical meaning of the black absorber perturbation is interpreted based on surface crossing and is numerically validated. In addition, the immediate reflection at the intermediate surface with a controlled direction change is investigated within the invariance framework. This approach can be advantageous for a void streaming problem.

  8. Semen cryopreservation and usage rate for assisted reproductive technology in 898 men with cancer.

    PubMed

    Muller, Iris; Oude Ophuis, Ralph J A; Broekmans, Frank J M; Lock, Tycho M T W

    2016-02-01

    An undesired side effect of cancer treatment is potential subfertility or infertility. Timely cryopreservation of semen is the best modality to ensure fertility. This retrospective data analysis established the usage rate of cryopreserved semen from cancer patients. Pubertal and post-pubertal patients who could become infertile as a result of cancer (treatment) were offered the option to cryopreserve semen prior to treatment. Of the 898 patients who cryopreserved their semen in our hospital, 96 (10.7%) used this for assisted reproductive technology. The live birth rates for intrauterine insemination, in-vitro fertilization, intracytoplasmic sperm injection and cryopreserved embryo transfer were 13%, 29%, 32% and 17%, respectively. Of all couples involved, 77% achieved parenthood, i.e. 60 of the 78 patients (with complete follow-up) fathered at least one child. PMID:26687904

  9. Fundamentals of Composite Materials for Undergraduate Engineering--A Filmed Presentation. Final Report.

    ERIC Educational Resources Information Center

    Busching, Herbert W.

    Curricula in undergraduate engineering have not adequately reflected present usage and knowledge of composite materials (types of rock and organic matter in which structurally dissimilar materials are combined). Wide usage of composites is expected to increase the importance of this class of materials and the need for more substantive exposure to…

  10. Magnetoelectric coupling at metal surfaces

    SciTech Connect

    Gerhard, Lukas; Yamada, T.K.; Balashov, T.; Takacs, A. F.; Wesselink, R.J.H.; Daene, Markus W; Fechner, M.; Ostanin, S.; Ernst, Arthur; Mertig, I.; Wulfhekel, Wulf

    2010-10-01

    Magnetoelectric coupling allows the magnetic state of a material to be changed by an applied electric field. To date, this phenomenon has mainly been observed in insulating materials such as complex multiferroic oxides. Bulk metallic systems do not exhibit magnetoelectric coupling, because applied electric fields are screened by conduction electrons. We demonstrate strong magnetoelectric coupling at the surface of thin iron films using the electric field from a scanning tunnelling microscope, and are able to write, store and read information to areas with sides of a few nanometres. Our work demonstrates that high-density, non-volatile information storage is possible in metals.

  11. Influence of pre- and post-usage flushing frequencies on bacterial water quality of non-touch water fittings

    PubMed Central

    2013-01-01

    Background Non-touch fittings have been reported to be susceptible for Pseudomonas aeruginosa accumulation. A number of factors may contribute to this, including the frequency of usage, duration of water stagnation, or presence of plastic materials. Programmable non-touch fittings are appearing which allow regular automated post-flushing with cold water to prevent water stagnation. However, the ideal duration of post-flushing is unknown as well as the effect of pre-rinsing with cold water before use. Methods Eight non-touch fittings with brass valve blocks were mounted on a mobile test sink and connected to the same central water pipe source, differing only in presence or absence of water connection pipes, length of connection pipe, frequency of usage, and time intervals for pre- and post-usage water flush. The total bacteria colony-forming unit (cfu) counts were obtained by the spread plate technique. Results Low frequency of water use in combination with a long stagnating water column resulted in high bacterial cfu counts. Post-usage flushing for 2 seconds did not differ from no flushing. Flushing for 10 seconds with cold water after use or 30 seconds flush before use were both the most effective measures to prevent non-touch fittings from biofilm formation over a period of 20 weeks. Conclusion Further improvements in water fitting technology could possibly solve the problem of bacterial water contamination in health care settings. PMID:24000790

  12. BAO Plate Archive digitization, creation of electronic database and its scientific usage

    NASA Astrophysics Data System (ADS)

    Mickaelian, Areg M.

    2015-08-01

    Astronomical plate archives created on the basis of numerous observations at many observatories are important part of the astronomical heritage. Byurakan Astrophysical Observatory (BAO) plate archive consists of 37,500 photographic plates and films, obtained at 2.6m telescope, 1m and 0.5m Schmidt telescopes and other smaller ones during 1947-1991. In 2002-2005, the famous Markarian Survey (First Byurakan Survey, FBS) 2000 plates were digitized and the Digitized FBS (DFBS, http://www.aras.am/Dfbs/dfbs.html) was created. New science projects have been conducted based on these low-dispersion spectroscopic material. In 2015, we have started a project on the whole BAO Plate Archive digitization, creation of electronic database and its scientific usage. A Science Program Board is created to evaluate the observing material, to investigate new possibilities and to propose new projects based on the combined usage of these observations together with other world databases. The Executing Team consists of 9 astronomers and 3 computer scientists and will use 2 EPSON Perfection V750 Pro scanners for the digitization, as well as Armenian Virtual Observatory (ArVO) database to accommodate all new data. The project will run during 3 years in 2015-2017 and the final result will be an electronic database and online interactive sky map to be used for further research projects.

  13. Nanoscopic Study of the Polarization-Strain Coupling in Relaxor Ferroelectric and the Search for New Relaxor Materials for Transducer and Optical Applications

    SciTech Connect

    J. Toulouse

    2007-05-31

    evolution from the nanoscopic to the mesoscopic polar order and even to a macroscopic polar order in the presence of an applied electric field. The results of this study also provide a physical model to explain the very strong polarization-strain coupling in these relaxors.

  14. Combined Electron Paramagnetic Resonance and Atomic Absorption Spectroscopy/Inductively Coupled Plasma Analysis As Diagnostics for Soluble Manganese Species from Mn-Based Positive Electrode Materials in Li-ion Cells.

    PubMed

    Shilina, Yuliya; Ziv, Baruch; Meir, Aviv; Banerjee, Anjan; Ruthstein, Sharon; Luski, Shalom; Aurbach, Doron; Halalay, Ion C

    2016-04-19

    Manganese dissolution from positive electrodes significantly reduces the durability of lithium-ion batteries. Knowledge of dissolution rates and oxidation states of manganese ions is essential for designing effective mitigation measures for this problem. We show that electron paramagnetic resonance (EPR) combined with atomic absorption spectroscopy (AAS) or inductively coupled plasma (ICP) can determine both manganese dissolution rates and relative Mn(3+) amounts, by comparing the correlation between EPR and AAS/ICP data for Mn(2+) standards with that for samples containing manganese cations dissolved from active materials (LiMn2O4 (LMO) and LiNi0.5Mn1.5O4 (LNMO)) into the same electrolyte solution. We show that Mn(3+), and not Mn(2+), is the dominant species dissolved from LMO, while Mn(2+) is predominant for LNMO. Although the dissolution rate of LMO varies significantly for the two investigated materials, due to particle morphology and the presence of Cr in one of them, the Mn speciation appears independent of such details. Thus, the relative abundance of dissolved manganese ions in various oxidation states depends mainly on the overall chemical identity of the active material (LMO vs LNMO). We demonstrate the relevance of our methodology for practical batteries with data for graphite-LMO cells after high-temperature cycling or stand at 4.2 V. PMID:27018717

  15. Impact tolerant material

    NASA Technical Reports Server (NTRS)

    Heyman, Joseph S. (Inventor)

    1990-01-01

    A material is protected from acoustic shock waves generated by impacting projectiles by means of a backing. The backing has an acoustic impedance that efficiently couples the acoustic energy out of the material.

  16. Examining Internet Usage Demographic Differences and the Relationship between Internet Usage and Business Outcomes in Sierra Leone

    ERIC Educational Resources Information Center

    Kamara, Mohamed K.

    2013-01-01

    This study utilized the unified theory of acceptance and use of technology (UTAUT) to determine Internet users' perceptions and behavioral intentions to accept Wi-Fi technology deployment in Sierra Leone. The study sought to investigate (a) the Internet usage rates before and after Wi-Fi adaption in Freetown; (b) differences in Internet usage…

  17. Tribological properties of ceramic/Ti3Al-Nb sliding couples for use as candidate seal materials to 700 deg C

    NASA Technical Reports Server (NTRS)

    Dellacorte, Christopher; Steinetz, Bruce M.; Brindley, Pamela K.

    1989-01-01

    Tribological properties of Ti3Al-Nb intermetallic disks sliding against alumina-boria-silicate fabric were ascertained in air at temperatures from 25 to 700 C. These materials are candidates for sliding seal applications for the National AeroSpace Plane. The tests were done using a pin on disk tribometer. Sliding was unidirectional at 0.27 m/sec under a nominal contact stress of 340 kPa. Gold sputter or ion plating deposited films were used to reduce friction and wear. Rhodium and palladium films were used beneath the gold lubricating films to prevent diffusion of the substrate into the gold at high temperature. The friction and wear of the unlubricated specimens was unacceptable. Friction coefficients were generally greater than 1.0. The ion plated gold films, when used with a rhodium diffusion barrier reduced friction by almost a factor of 2. Wear was also substantially reduced. The sputter deposited films were not adherent unless the substrate was sputter cleaned immediately prior to film deposition. Palladium did not function as a diffusion barrier.

  18. Tribological properties of ceramic-(Ti3Al-Nb) sliding couples for use as candidate seal materials to 700 C

    NASA Technical Reports Server (NTRS)

    Dellacorte, Christhopher; Steinetz, Bruce M.; Brindley, Pamela K.

    1990-01-01

    Tribological properties of Ti3Al-Nb intermetallic disks sliding against alumina-boria-silicate fabric were ascertained in air at temperatures from 25 to 700 C. These materials are candidates for sliding seal applications for the National AeroSpace Plane. The tests were done using a pin on disk tribometer. Sliding was unidirectional at 0.27 m/sec under a nominal contact stress of 340 kPa. Gold sputter or ion plating deposited films were used to reduce friction and wear. Rhodium and palladium films were used beneath the gold lubricating films to prevent diffusion of the substrate into the gold at high temperature. The friction and wear of the unlubricated specimens was unacceptable. Friction coefficients were generally greater than 1.0. The ion plated gold films, when used with a rhodium diffusion barrier reduced friction by almost a factor of 2. Wear was also substantially reduced. The sputter deposited films were not adherent unless the substrate was sputter cleaned immediately prior to film deposition. Palladium did not function as a diffusion barrier.

  19. Inference of the phase-to-mechanical property link via coupled X-ray spectrometry and indentation analysis: Application to cement-based materials

    SciTech Connect

    Krakowiak, Konrad J.; Wilson, William; James, Simon; Musso, Simone; Ulm, Franz-Josef

    2015-01-15

    A novel approach for the chemo-mechanical characterization of cement-based materials is presented, which combines the classical grid indentation technique with elemental mapping by scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDS). It is illustrated through application to an oil-well cement system with siliceous filler. The characteristic X-rays of major elements (silicon, calcium and aluminum) are measured over the indentation region and mapped back on the indentation points. Measured intensities together with indentation hardness and modulus are considered in a clustering analysis within the framework of Finite Mixture Models with Gaussian component density function. The method is able to successfully isolate the calcium-silica-hydrate gel at the indentation scale from its mixtures with other products of cement hydration and anhydrous phases; thus providing a convenient means to link mechanical response to the calcium-to-silicon ratio quantified independently via X-ray wavelength dispersive spectroscopy. A discussion of uncertainty quantification of the estimated chemo-mechanical properties and phase volume fractions, as well as the effect of chemical observables on phase assessment is also included.

  20. FUNDAMENTAL PROPERTIES OF ULTRA HIGH PERFORMANCE-STRAIN HARDENING CEMENTITIOUS COMPOSITES AND USAGE FOR REPAIR

    NASA Astrophysics Data System (ADS)

    Kunieda, Minoru; Shimizu, Kosuke; Eguchi, Teruyuki; Ueda, Naoshi; Nakamura, Hikaru

    This paper presents the fundamental properties of Ultra High Performance-Strain Hardening Cementitious Composites (UHP-SHCC), which were depeloped for repair applications. In particular, mechanical properties such as tensile response, shrinkage and bond strength were investigated experimentally. Protective performance of the material such as air permeability, water permeability and penetration of chloride ion was also confirmed comparing to that of ordinary concrete. This paper also introduces the usage of the material in repair of concrete st ructures. Laboratory tests concerining the deterioration induced by corrosion were conducted. The UHP-SHCC that coverd the RC beam resisted not only crack opening along the rebar due to corrosion but also crack opening due to loading tests.

  1. Outgassing Data for Selecting Spacecraft Materials

    NASA Technical Reports Server (NTRS)

    Campbell, William A., Jr.; Marriott, Richard S.; Park, John J.

    1984-01-01

    Outgassing data, derived from tests at 396 K (125 C) for 24 hours in vacuum as per ASTM E 595-77, have been compiled for numerous materials for spacecraft use. The data presented are the total mass loss (TML) and the collected volatile condensable materials (CVCM). The various materials are compiled by likely usage and alphabetically.

  2. Tensions Between Materials and Environmental Quality

    ERIC Educational Resources Information Center

    Carpenter, Richard A.

    1976-01-01

    Conflicts between economic growth and environmental awareness will change availability and usage of materials. Environmental protection will increase materials costs, restrict land use for manufacturing sites and mineral extraction, and divert capital from expansion. The tradeoff for undesirable effects will be materials conservation and improved…

  3. Influence of material coupling and assembly condition on the magnitude of micromotion at the stem-neck interface of a modular hip endoprosthesis.

    PubMed

    Jauch, S Y; Huber, G; Hoenig, E; Baxmann, M; Grupp, T M; Morlock, M M

    2011-06-01

    Hip prostheses with a modular neck exhibit, compared to monobloc prostheses, an additional interface which bears the risk of fretting as well as corrosion. Failures at the neck adapter of modular prostheses have been observed for a number of different designs. It has been speculated that micromotions at the stem-neck interface were responsible for these implant failures. The purpose of this study was to investigate the influence of material combinations and assembly conditions on the magnitude of micromotions at the stem-neck interface during cyclic loading. Modular (n = 24) and monobloc (n = 3) hip prostheses of a similar design (Metha, Aesculap AG, Tuttlingen, Germany) were subjected to mechanical testing according to ISO 7206-4 (F(min) = 230N, F(max) = 2300N, f = 1Hz, n = 10,000 cycles). The neck adapters (Ti-6Al-4V or Co-Cr29-Mo alloy) were assembled with a clean or contaminated interface. The micromotion between stem and neck adapter was calculated at five reference points based on the measurements of the three eddy current sensors. The largest micromotions were observed at the lateral edge of the stem-neck taper connection, which is in accordance with the crack location of clinically failed prostheses. Titanium neck adapters showed significantly larger micromotions than cobalt-chromium neck adapters (p = 0.005). Contaminated interfaces also exhibited significantly larger micromotions (p < 0.001). Since excessive micromotions at the stem-neck interface might be involved in the process of implant failure, special care should be taken to clean the interface prior to assembly and titanium neck adapters with titanium stems should generally be used with caution. PMID:21531416

  4. Outgassing data for spacecraft materials

    NASA Technical Reports Server (NTRS)

    Campbell, W. A., Jr.; Marriott, R. S.; Park, J. J.

    1980-01-01

    A system for determining the mass loss in vacuum and for collecting the outgassed compounds was developed. Outgassing data, derived from tests at 398 K (125 degrees C) for 24 hours in vacuum as per ASTM E 59577, are compiled for numerous materials for spacecraft use. The data presented are the total mass loss (TML) and the collected volatile condensable materials (CVCM). The various materials are compiled by likely usage and alphabetically.

  5. Prevalence, Incidence, and Factor Concentrate Usage Trends of Hemophiliacs in Taiwan

    PubMed Central

    Tu, Tsu-Chiang; Liou, Wen-Shyong; Chou, Tsui-Yun; Lin, Tsung-Kun; Lee, Chuan-Fang; Chen, Jye-Daa; Cham, Thau-Ming

    2013-01-01

    Purpose Hemophilia A and B (HA, HB) are the most common X-linked inherited bleeding disorders. The introduction of factor concentrates has allowed for control of the lifelong chronic disease. However, no studies have been published regarding the epidemiology of hemophilia in Taiwan. Our aim was to determine the prevalence, incidence, and mortality rate, as well as trends in the use of factor concentrates, in individuals with hemophilia in Taiwan. Materials and Methods A retrospective study was conducted using the National Health Insurance Research Database between 1997 and 2007. Results We identified 988 males with hemophilia (HA : HB ratio=5.4 : 1). The mean prevalence per 100000 males was 6.7±0.1 for HA and 1.2±0.1 for HB. The estimated mean annual incidence per live male birth was 1 in 10752 for HA and 1 in 47619 for HB. Standardized mortality ratios for males with hemophilia (all severities) or severe hemophilia were 1.3- and 2.1-fold higher than that of the general male population, respectively. Mean factor VIII (FVIII) and factor IX (FIX) usage was 1.5003±0.4029 and 0.3126±0.0904 international units (IUs) per capita, respectively. Mean FVIII and FIX usage per patient with hemophilia (all severities) or severe hemophilia was 44027±11532 and 72341±17298, respectively, and 49407±13015 and 74369±18411 IUs per person with HA or HB, respectively. Conclusion Our data revealed epidemiologic and factor concentrate usage trends in males with hemophilia in Taiwan, highlighting a need for improvements in the mandatory National Health Insurance registry. A better-designed, patient-centered registry system would enable more detailed patient information collection and analysis, improving subsequent care. PMID:23225801

  6. Seat belt usage: A potential target for applied behavior analysis

    PubMed Central

    Geller, E. Scott; Casali, John G.; Johnson, Richard P.

    1980-01-01

    Results of 1,579 observations of cars entering or exiting campus parking lots showed direct relationships between seat belt wearing and the intrusiveness of the engineering device designed to induce belt usage, and between device intrusiveness and system defeat. For example, all drivers with working interlocks or unlimited buzzer reminders were wearing a seat belt; but 62% of the systems with interlocks or unlimited buzzers had been defeated, and only 15.9% of the drivers in these cars were wearing a seat belt. The normative data indicated marked ineffectiveness of the negative reinforcement contingencies implied by current seat belt inducement systems; but suggested that unlimited buzzer systems would be the optimal system currently available if contingencies were developed to discourage the disconnection and circumvention of such systems. Positive reinforcement strategies are discussed that would be quite feasible for large-scale promotion of seat belt usage. PMID:16795638

  7. Effects of Perceived Values on Continuance Usage of Facebook

    NASA Astrophysics Data System (ADS)

    Yang, Heng-Li; Lai, Cheng-Yu

    Facebook is one of the renowned social networking sites (SNS) on the Internet. As compared to the conventional SNS, it not only provides social interaction features, but has more entertainment elements on the website. Many Facebook users use the website for the purpose of playing the embedded games rather than use its original social features, i.e., individual's perceived values about the usage of Facebook may have changed. Consequently, it is an interesting issue to know individual's perceived values and satisfaction toward continuance usage of the new style SNS like Facebook. Based on prior literatures, three different value orientations, including social orientation, entertainment orientation and fashion orientation, were adopted in this study to examine their influence on individual's satisfaction and continuance intention to use Facebook. An empirical survey and partial least squares (PLS) technology was utilized to test the proposed hypotheses. Several empirical results were found. Both academic and practical implications are discussed.

  8. textbf{Historical Usage Inventories of DDT in China}

    NASA Astrophysics Data System (ADS)

    Qiang, Wang; Lijuan, Zhao; Jianxin, Hu

    2010-05-01

    Dichlorodiphenyltrichloroethane (DDT) is one of organochlorine pesticides and listed as one of the persistent organic pollutants to be reduced and finally eliminated in the Stockholm Convention on Persistent Organic Pollutants, because of its great persistence, toxics, bio-accumulation and potential for long-range transport. It is critical to create national DDT usage/emission inventories for China to carry out source-receptor relation analysis, risk assessment, and other research related to DDT in this country. Chinese inventories of DDT to the year1983 have been published; however, DDT is still being used indirectly in the dicifol producing and being applied for malaria control in case. Therefore it is needed to supplement and update the inventories. DDT production in China can be divided into three phases. Prior to 1965 is the first stage with an annual output of no more than 10,000 tons; 1966-1983 is the second phase. At this stage DDT was produced with an average annual production of 15,500 tons. After 1984 is the third production phase, of which the average annual DDT production was 6,465 tons. Before 1983, DDT was mainly used for agriculture, forestry and pesticides.China used a total of 270,000 tons of DDT during 1951 - 1983. According to China's cropland area, Li Yi-fan create China's DDT usage inventory of 1951-1983. In 1983 the State Council decided to ban DDT producing and DDT is no longer used in agriculture any more, but it is still being used in the producing of dicofol, malaria prevention and treatment anda small amount for export. To this end, this paper calculated theusage inventory of China's DDT from 1984 to 2003. Using sown areas of cotton, apple, citrus, tea and vegetable as surrogate data, usage of dicifolwas calculated, then the usage inventory of DDT resulting from dicofol use and DDT applied for malaria control with prefecture resolution was created. From 1984 to 2003, China used 15,312 tons of DDT, including 12,912 tons of DDT resulting

  9. Assessing usage patterns of electronic clinical documentation templates.

    PubMed

    Vawdrey, David K

    2008-01-01

    Many vendors of electronic medical records support structured and free-text entry of clinical documents using configurable templates. At a healthcare institution comprising two large academic medical centers, a documentation management data mart and a custom, Web-accessible business intelligence application were developed to track the availability and usage of electronic documentation templates. For each medical center, template availability and usage trends were measured from November 2007 through February 2008. By February 2008, approximately 65,000 electronic notes were authored per week on the two campuses. One site had 934 available templates, with 313 being used to author at least one note. The other site had 765 templates, of which 480 were used. The most commonly used template at both campuses was a free text note called "Miscellaneous Nursing Note," which accounted for 33.3% of total documents generated at one campus and 15.2% at the other. PMID:18998863

  10. Mobile phones: time to rethink and limit usage.

    PubMed

    Paul, Bobby; Saha, Indranil; Kumar, Sanjay; Samim Ferdows, S K; Ghose, Gautam

    2015-01-01

    Radiofrequency waves generated from mobile phones cause potential public health problems. Short-term effects like changes in sleep, heart rate, and blood pressure, and long-term effects like carcinoma are well documented. The Government of India's efforts in laying down regulations regarding the safety limits, manufacture, marketing, and mobile use are still in nascent stage. The need for stringent enforcement of laws for prevention of phone usage while driving and guidelines of medical regulatory bodies regarding rules and regulations of phone usage while at class or attending patients is of utmost importance. This should be supplemented by mass media to raise awareness among people regarding the possible health effects of radiofrequency emissions from mobile phones and the guidelines to minimize its exposure. It is the need of the hour to teach young people to be structured, to know when to have the cell phone on, and to avoid becoming the slave of technology instead of its mastery. PMID:25758729

  11. Long memory in patterns of mobile phone usage

    NASA Astrophysics Data System (ADS)

    Owczarczuk, Marcin

    2012-02-01

    In this article we show that usage of a mobile phone, i.e. daily series of number of calls made by a customer, exhibits long memory. We use a sample of 4502 postpaid users from a Polish mobile operator and study their two-year billing history. We estimate Hurst exponent by nine estimators: aggregated variance method, differencing the variance, absolute values of the aggregated series, Higuchi's method, residuals of regression, the R/S method, periodogram method, modified periodogram method and Whittle estimator. We also analyze empirically relations between estimators. Long memory implies an inertial effect in clients' behavior which may be used by mobile operators to accelerate usage and gain additional profit.

  12. The incidence of postoperative pain and analgesic usage in children.

    PubMed

    Acs, G; Drazner, E

    1992-01-01

    The purpose of this study is to report the incidence of post-restorative dental pain and analgesic usage in children. A questionnaire completed by parents was employed. The mean age of the patients was 8.1 years; and all patients were in the six- to thirteen-year-old range. Pain following routine restorative procedures was reported by 31.5 percent of the patients. Additionally, 52.9 percent of these patients required analgesic relief. PMID:1537941

  13. Fuel bundle design for enhanced usage of plutonium fuel

    DOEpatents

    Reese, A.P.; Stachowski, R.E.

    1995-08-08

    A nuclear fuel bundle includes a square array of fuel rods each having a concentration of enriched uranium and plutonium. Each rod of an interior array of the rods also has a concentration of gadolinium. The interior array of rods is surrounded by an exterior array of rods void of gadolinium. By this design, usage of plutonium in the nuclear reactor is enhanced. 10 figs.

  14. What Affects Clinicians’ Usage of Health Information Exchange?

    PubMed Central

    Rudin, R.; Volk, L.; Simon, S.; Bates, D.

    2011-01-01

    Background The ability to electronically exchange health information among healthcare providers holds enormous promise to improve care coordination and reduce costs. Provider-to-provider data exchange is an explicit goal of the American Recovery and Reinvestment Act of 2009 and may be essential for the long-term success of the Affordable Care Act of 2010. However, little is known about what factors affect clinicians’ usage of health information exchange (HIE) functionality. Objective To identify factors that affect clinicians’ HIE usage - in terms of frequency of contributing data to and accessing data from aggregate patient records - and suggest policies for fostering its usage. Methods We performed a qualitative study using grounded theory by interviewing clinician-users and HIE staff of one operational HIE which supported aggregate patient record functionality. Fifteen clinicians were interviewed for one hour each about what factors affect their HIE usage. Five HIE staff were asked about technology and training issues to provide context. Interviews were recorded, transcribed and analyzed. Recruitment excluded clinicians with little or no familiarity with the HIE and was restricted to one community and a small number of specialties. Results Clinicians were motivated to access the HIE by perceived improvements in care quality and time savings, but their motivation was moderated by an extensive list of factors including gaps in data, workflow issues and usability issues. HIE access intensities varied widely by clinician. Data contribution intensities to the HIE also varied widely and were affected by billing concerns and time constraints. Conclusions Clinicians, EHR and HIE product vendors and trainers should work toward integrating HIE into clinical workflows. Policies should create incentives for HIE organizations to assist clinicians in using HIE, develop measures of HIE contributions and accesses, and create incentives for clinicians to contribute data to

  15. Usage of microplasma signal noise for solar cells diagnostic

    NASA Astrophysics Data System (ADS)

    Vanek, Jiri; Koktavy, Pavel; Kubickova, Kristyna; Sadovsky, Petr; Raska, Michal

    2007-06-01

    This work deals with the usage of micro-plasmas signal noise for solar cells diagnostic. When high electric field is applied to PN junction with some technological imperfections it produces in tiny areas of enhanced impact ionization called micro-plasmas which could lead to deterioration in quality or destruction of PN junction. On this account it is possible to use methods which indicate presence of micro-plasma in junction and enable quality and quantitative description of tested cells.

  16. Lemierre's syndrome in a patient with habitual toothpick usage.

    PubMed

    Wu, Alice Ying-Jung; Tseng, Hsiang-Kuang; Su, Jian; Liu, Chang-Pan

    2013-06-01

    Lemierre's syndrome is characterized by septic thrombophlebitis of the internal jugular vein that is complicated by metastatic infections. The disease usually presents after oropharyngeal infection. In rare cases, odontogenic infection has been implicated as culprit. Here, we report a case of Lemierre's syndrome that most likely developed secondary to toothpick usage. The patient had an uneventful recovery after the timely administration of the appropriate antibiotics. PMID:22487510

  17. Receptor usage and cell entry of porcine epidemic diarrhea coronavirus.

    PubMed

    Liu, Chang; Tang, Jian; Ma, Yuanmei; Liang, Xueya; Yang, Yang; Peng, Guiqing; Qi, Qianqian; Jiang, Shibo; Li, Jianrong; Du, Lanying; Li, Fang

    2015-06-01

    Porcine epidemic diarrhea coronavirus (PEDV) has significantly damaged America's pork industry. Here we investigate the receptor usage and cell entry of PEDV. PEDV recognizes protein receptor aminopeptidase N from pig and human and sugar coreceptor N-acetylneuraminic acid. Moreover, PEDV infects cells from pig, human, monkey, and bat. These results support the idea of bats as an evolutionary origin for PEDV, implicate PEDV as a potential threat to other species, and suggest antiviral strategies to control its spread. PMID:25787280

  18. Alcohol Usage and Abrupt Cessation Modulate Diurnal Activity

    PubMed Central

    Norrell, Stacy; Reyes-Vasquez, Cruz; Burau, Keith; Dafny, Nachum

    2010-01-01

    Alcohol has many effects throughout the body. The effect on circadian rhythms and the correlation of these effects to withdrawal effects of alcohol present interesting findings. By measuring 3 planes of activity of female Sprague-Dawley rats during alcohol usage and continuing study through the first two days following withdrawal of alcohol allow for the observation of a drastic modulation of the circadian pattern of activity. PMID:20615456

  19. Predicting Heroin and Alcohol Usage Among Young Puerto Ricans.

    ERIC Educational Resources Information Center

    Nuttall, Ronald L.; Nuttall, Ena Vazquez

    Using 1968 data collected from junior and senior high school students in Bayamon, Puerto Rico, substance usage patterns for heroin and alcohol were predicted for 1975-6. A sample of 1,000 of the initial 5,000 students were selected for re-interview; half were selected to be at high risk of substance abuse and half were selected randomly. Some 657…

  20. [Codon usage bias in the straw mushroom Volvariella volvacea].

    PubMed

    Jiang, Wei; Lü, Beibei; He, Jianhua; Wang, Jinbin; Wu, Xiao; Wu, Guogan; Bao, Dapeng; Chen, Mingjie; Zhang, Jinsong; Tan, Qi; Tang, Xueming

    2014-09-01

    We analyzed the whole genome coding sequence of Volvariella volvacea to study the pattern utilization of codons by Codon W 1.4.2. As results, 24 optimal codons were identified. Moreover, the frequency of codons usage was calculated by CUSP program. We compared the frequency of codons usage of V. volvacea with other organisms including 6 modal value species (Homo sapiens, Saccharomys cerevisiae, Arabidopsis thalian, Mus musculus, Danio rerio and Drosophila melanogaster) and 4 edible fungi (Coprinopsis cinerea, Agaricus bisporus, Lentinula edodes and Pleurotus ostreatus). We found that there were less differences in 3 edible fungi (excluding Pleurotus ostreatus) than 6 modal value species, comparing with the frequency of codons usage of V. volvacea. With software SPSS16.0, cluster analysis which showed differences in the size of codon bias, reflects the evolutionary relationships between species, which can be used as a reference of evolutionary relationships of species. This was the first time for analysis the codon preference among the whole coding sequences of edible fungi, serving as theoretical basis to apply genetic engineering of V. volvacea. PMID:25720157

  1. Electricity Usage Scheduling in Smart Building Environments Using Smart Devices

    PubMed Central

    Lee, Eunji; Bahn, Hyokyung

    2013-01-01

    With the recent advances in smart grid technologies as well as the increasing dissemination of smart meters, the electricity usage of every moment can be detected in modern smart building environments. Thus, the utility company adopts different price of electricity at each time slot considering the peak time. This paper presents a new electricity usage scheduling algorithm for smart buildings that adopts real-time pricing of electricity. The proposed algorithm detects the change of electricity prices by making use of a smart device and changes the power mode of each electric device dynamically. Specifically, we formulate the electricity usage scheduling problem as a real-time task scheduling problem and show that it is a complex search problem that has an exponential time complexity. An efficient heuristic based on genetic algorithms is performed on a smart device to cut down the huge searching space and find a reasonable schedule within a feasible time budget. Experimental results with various building conditions show that the proposed algorithm reduces the electricity charge of a smart building by 25.6% on average and up to 33.4%. PMID:24453860

  2. Migraine prophylactic medication usage patterns in The Netherlands.

    PubMed

    Rahimtoola, H; Buurma, H; Tijssen, C C; Leufkens, H G; Egberts, A C G

    2003-05-01

    This study aims to investigate usage patterns of specific migraine prophylactic medications in ergotamine and triptan patients commencing this treatment for the first time during 1 January 1992 until 31 December 1998. Usage patterns of specific migraine prophylactic drugs were evaluated for each patient by accessing data from a large prescription database and were characterized as continued, switch or stop use during the patient observation period. Several patient and medication-related factors were explored in order to identify a possible relationship with the specific usage pattern defined. Approximately 75% of the study population (n = 729) had terminated (stop or switch) prophylactic treatment after 1 year. Age < 40 years (relative risk (RR) 1.9; 95% confidence interval (CI) 1.2-3.2) and the concomitant use of non-steroidal anti-inflammatory drugs (RR 3.2; 95% CI 1.2-5.5) or specific abortive migraine drugs resulted in a faster onset of treatment modification (switch). Overall, migraine prophylactic treatment is used for a relatively short period, probably attributable to the common limitations associated with migraine prophylaxis, such as poor compliance and/or limited therapeutic efficacy. Patterns of use can be influenced by a variety of factors, including age, type of prescriber and certain co-medication. Patient interview studies are required to clarify these issues further. PMID:12716348

  3. Red Storm usage model :Version 1.12.

    SciTech Connect

    Jefferson, Karen L.; Sturtevant, Judith E.

    2005-12-01

    Red Storm is an Advanced Simulation and Computing (ASC) funded massively parallel supercomputer located at Sandia National Laboratories (SNL). The Red Storm Usage Model (RSUM) documents the capabilities and the environment provided for the FY05 Tri-Lab Level II Limited Availability Red Storm User Environment Milestone and the FY05 SNL Level II Limited Availability Red Storm Platform Milestone. This document describes specific capabilities, tools, and procedures to support both local and remote users. The model is focused on the needs of the ASC user working in the secure computing environments at Los Alamos National Laboratory (LANL), Lawrence Livermore National Laboratory (LLNL), and SNL. Additionally, the Red Storm Usage Model maps the provided capabilities to the Tri-Lab ASC Computing Environment (ACE) requirements. The ACE requirements reflect the high performance computing requirements for the ASC community and have been updated in FY05 to reflect the community's needs. For each section of the RSUM, Appendix I maps the ACE requirements to the Limited Availability User Environment capabilities and includes a description of ACE requirements met and those requirements that are not met in that particular section. The Red Storm Usage Model, along with the ACE mappings, has been issued and vetted throughout the Tri-Lab community.

  4. Codon Usage Bias and Determining Forces in Taenia solium Genome.

    PubMed

    Yang, Xing; Ma, Xusheng; Luo, Xuenong; Ling, Houjun; Zhang, Xichen; Cai, Xuepeng

    2015-12-01

    The tapeworm Taenia solium is an important human zoonotic parasite that causes great economic loss and also endangers public health. At present, an effective vaccine that will prevent infection and chemotherapy without any side effect remains to be developed. In this study, codon usage patterns in the T. solium genome were examined through 8,484 protein-coding genes. Neutrality analysis showed that T. solium had a narrow GC distribution, and a significant correlation was observed between GC12 and GC3. Examination of an NC (ENC vs GC3s)-plot showed a few genes on or close to the expected curve, but the majority of points with low-ENC (the effective number of codons) values were detected below the expected curve, suggesting that mutational bias plays a major role in shaping codon usage. The Parity Rule 2 plot (PR2) analysis showed that GC and AT were not used proportionally. We also identified 26 optimal codons in the T. solium genome, all of which ended with either a G or C residue. These optimal codons in the T. solium genome are likely consistent with tRNAs that are highly expressed in the cell, suggesting that mutational and translational selection forces are probably driving factors of codon usage bias in the T. solium genome. PMID:26797435

  5. Codon Usage Bias and Determining Forces in Taenia solium Genome

    PubMed Central

    Yang, Xing; Ma, Xusheng; Luo, Xuenong; Ling, Houjun; Zhang, Xichen; Cai, Xuepeng

    2015-01-01

    The tapeworm Taenia solium is an important human zoonotic parasite that causes great economic loss and also endangers public health. At present, an effective vaccine that will prevent infection and chemotherapy without any side effect remains to be developed. In this study, codon usage patterns in the T. solium genome were examined through 8,484 protein-coding genes. Neutrality analysis showed that T. solium had a narrow GC distribution, and a significant correlation was observed between GC12 and GC3. Examination of an NC (ENC vs GC3s)-plot showed a few genes on or close to the expected curve, but the majority of points with low-ENC (the effective number of codons) values were detected below the expected curve, suggesting that mutational bias plays a major role in shaping codon usage. The Parity Rule 2 plot (PR2) analysis showed that GC and AT were not used proportionally. We also identified 26 optimal codons in the T. solium genome, all of which ended with either a G or C residue. These optimal codons in the T. solium genome are likely consistent with tRNAs that are highly expressed in the cell, suggesting that mutational and translational selection forces are probably driving factors of codon usage bias in the T. solium genome. PMID:26797435

  6. Electricity usage scheduling in smart building environments using smart devices.

    PubMed

    Lee, Eunji; Bahn, Hyokyung

    2013-01-01

    With the recent advances in smart grid technologies as well as the increasing dissemination of smart meters, the electricity usage of every moment can be detected in modern smart building environments. Thus, the utility company adopts different price of electricity at each time slot considering the peak time. This paper presents a new electricity usage scheduling algorithm for smart buildings that adopts real-time pricing of electricity. The proposed algorithm detects the change of electricity prices by making use of a smart device and changes the power mode of each electric device dynamically. Specifically, we formulate the electricity usage scheduling problem as a real-time task scheduling problem and show that it is a complex search problem that has an exponential time complexity. An efficient heuristic based on genetic algorithms is performed on a smart device to cut down the huge searching space and find a reasonable schedule within a feasible time budget. Experimental results with various building conditions show that the proposed algorithm reduces the electricity charge of a smart building by 25.6% on average and up to 33.4%. PMID:24453860

  7. Alcohol and drug usage; and adolescents' sexual behaviour in Nigeria.

    PubMed

    Nwagu, Evelyn N

    2016-06-01

    This study determined students' perception of the influence of alcohol and drug usage on adolescents' sexual behaviours in Nigeria. The instrument for data collection was a researcher-made questionnaire. The population for the study comprised all students in government secondary schools in Enugu state, Nigeria. The sample was made up of 600 students randomly selected from the population. Means, t-test and ANOVA were used for data analysis. The result of the study revealed that there were significant differences at 0.05 level of significance in the mean perception of the students of the influence of alcohol and drug usage on adolescents' sexual behaviours when they were classified by gender and class. All the students irrespective of age agreed that alcohol and drug usage negatively influence sexual behaviour. The students perceived that students who do not take alcohol usually control their sexual desires while rape is common with students who are drug users. It was recommended among others that preventive health programmes meant to address adolescents' sexuality should be combined with appropriate drug education for maximum benefit. PMID:25661666

  8. Hospital-based rental programs to increase car seat usage.

    PubMed

    Colletti, R B

    1983-05-01

    The ability of hospital-based car seat rental programs to provide car seats inexpensively throughout an entire state and the effect of these rental programs on car seat usage by newborns were evaluated. In July 1979 individuals and groups committed to child passenger safety formed a coalition called Vermont SEAT (Seatbelts Eliminate Automobile Tragedies). During the next 3 years SEAT asked the major hospitals in the state to allow volunteers to operate car seat rental programs on their premises. The number of rental programs increased from 0 to 13; the percentage of newborns born in a hospital with a rental program increased from 0% to 99%. The estimated statewide rate of car seat usage by newborns, based on observations at discharge at five hospitals, increased from 15% to 70%. These findings suggest that a network of hospital-based car seat rental programs operated by volunteers can make car seats readily available throughout a state or region, and can significantly increase car seat usage by newborns. It is recommended that such programs be a part of comprehensive strategies to improve child passenger safety. PMID:6835761

  9. Binary Particle Swarm Optimization based Biclustering of Web Usage Data

    NASA Astrophysics Data System (ADS)

    Rathipriya, R.; Thangavel, K.; Bagyamani, J.

    2011-07-01

    Web mining is the nontrivial process to discover valid, novel, potentially useful knowledge from web data using the data mining techniques or methods. It may give information that is useful for improving the services offered by web portals and information access and retrieval tools. With the rapid development of biclustering, more researchers have applied the biclustering technique to different fields in recent years. When biclustering approach is applied to the web usage data it automatically captures the hidden browsing patterns from it in the form of biclusters. In this work, swarm intelligent technique is combined with biclustering approach to propose an algorithm called Binary Particle Swarm Optimization (BPSO) based Biclustering for Web Usage Data. The main objective of this algorithm is to retrieve the global optimal bicluster from the web usage data. These biclusters contain relationships between web users and web pages which are useful for the E-Commerce applications like web advertising and marketing. Experiments are conducted on real dataset to prove the efficiency of the proposed algorithms.

  10. [Study on usage of pesticides in various countries].

    PubMed

    Yamamoto, Miyako; Toda, Miou; Tanaka, Keiko; Sugita, Takiko; Sasaki, Shiho; Uneyama, Chikako; Morikawa, Kaoru

    2007-01-01

    Usage of pesticides in food items in export countries was studied, focusing items which Japan imports in large quantity. Japan has imported field crops such as wheat, corn and soy bean, and also grapefruit in large quantity on a weight base, mainly from United States, Australia and Canada. While, Japan has imported various kinds of vegetables in which China had the largest share. We collected usage data of pesticides for 44 food items of 17 countries of 2004. Pesticides which were used frequently (usage rank within top ten in each item/country) were dichlorvos, carbofuran, chlorpyrifos, dimethoate (insecticides), mancozeb, carbendazim, thiophanate-methyl, chlorthalonil (fungicides), glyphosate, 2,4-D, paraquat, acetochlor (herbicides). Carbendazim, thiophanate-methyl, acetochlor and dichlorvos were mainly used in China. Dithiocarbamates are used frequently in various food items in various countries, and also frequently detected in monitoring in foreign countries. Some pesticides such as bisultap, monosultap, etaboxam and triazmate were used only in certain countries, and available information on toxicity or analytical method was very limited. Some of pesticides described above have not been analyzed in the pesticide residue monitoring in Japan before 2005,however, many of them are subjects of analysis for import food after 2006 with the enforcement of positivelist system for residues of pesticide and veterinary medicines in food in Japan. PMID:18220053

  11. Various forms of tobacco usage and its associated oral mucosal lesions

    PubMed Central

    Tatapudi, Ramesh; Sudhakara-Reddy, Reddy; Alapati, Satish; Pavani, Kotha; Sai-Praveen, Kotu-Nagavenkata

    2016-01-01

    Background To study the various forms of tobacco usage and its associated oral mucosal lesions among the patients attending Vishnu Dental College Bhimavaram. Material and Methods An observational cross-sectional study was conducted in a total of 450 patients who were divided into three groups based upon type of tobacco use, as Group-1 Reverse smoking, Group-2 Conventional smoking, Group-3 Smokeless tobacco group and each group consists of 150 subjects. Results Reverse smoking was observed to be more prevalent among old females with smoker’s palate and carcinomatous lesions being the most common. Conventional smoking was observed more in male patients with maximum occurrence of leukoplakia and tobacco associated melanosis. Smokeless tobacco habit was predominantly seen in younger males. Habit specific lesions like tobacco pouch keratosis, Oral Submucous Fibrosis (OSMF), Quid induced lichenoid reaction were noticed in smokeless tobacco habit group except for erythroplakia which was noticed only in conventional smoking group and it was not significant statistically. Conclusions In the present study it was found that the usage of reverse smoking habit was most commonly seen in females and this habit is practiced in and surrounding areas of Bhimavaram with more occurrence of carcinoma compared to conventional smoking and smokeless tobacco. Key words:Tobacco, reverse smoking, conventional smoking, smokeless tobacco, carcinoma. PMID:27034758

  12. South African rural community understanding of fermented foods preparation and usage

    PubMed Central

    Chelule, Paul K.; Mokgatle, Mathilda M.; Zungu, Lindiwe I.

    2015-01-01

    Background: The benefits of fermented foods consumption have been demonstrated in a number of research reports. These qualities have been demonstrated, for example, to reduce childhood diseases such as diarrhea and malnutrition. Thus, fermented foods may be recommended for improving the health and nutritional quality of traditional African foods and regular inclusion of fermented foods as part of the daily diet would be desirable. Aims: Lack of knowledge and understanding toward fermented food preparation may limit their usage. This study explores the South African community's understanding of fermented foods preparation and usage. Materials and Methods: This was a qualitative study using focus group interviews to determine the community's understanding and their perception of fermented foods preparation in the rural villages of Odi, in Gauteng Province between May and June 2012. The target population was the caregivers of children under 5 years, attending the hospital's antenatal clinic at the time of study. The information was transcribed, coded, and analyzed using NVivo software. Results: Most caregivers were aware of food fermentation process, and some of them could not clearly differentiate between fermented and unfermented foods. Although most participants knew what fermented foods were, there were misconceptions on how they were made. This was exemplified by the undesirable artifacts, labeled as ingredients, in the fermentation process. Conclusion: Caregivers demonstrated a fair knowledge of fermented foods but lack a standard preparation procedure for these foods. There is an urgent need to educate communities and conduct a health promotion campaign on the fermented foods and probiotics. PMID:27462624

  13. Monitoring Web Site Usage of e-Bug: A Hygiene and Antibiotic Awareness Resource for Children

    PubMed Central

    Rajapandian, Vijayamaharaj; Eley, Charlotte V; Hoekstra, Beverley A; Lecky, Donna M; McNulty, Cliodna AM

    2015-01-01

    Background e-Bug is an educational resource which teaches children and young people about microbes, hygiene, infection, and prudent antibiotic use. The e-Bug resources are available in over 22 different languages and they are used widely across the globe. The resources can be accessed from the e-Bug website. Objective The objective of this study was to analyze the usage of the e-Bug website in order to understand how users access the website, where and when they access the site, and to review variation in use across the different areas of the site. Methods The usage statistics for the e-Bug website were monitored by Google Analytics between September 2010 and August 2013. Results The statistics show the website had over 324,000 visits during the three years, from just under 250,000 visitors, with the number of visitors increasing year after year. Visitors accessed the website from 211 different countries, with more than 267,000 documents downloaded. The majority of visitors were from the United Kingdom and visited the English website, although countries such as France and Portugal were also frequent visitors. Conclusions These website statistics confirm that e-Bug is frequently used across Europe and highlight that e-Bug use has expanded across the world. The findings from this report will be used to inform future modifications or updates to the materials, as well as the development of new educational resources. PMID:26567127

  14. Joint used for coupling long heaters

    DOEpatents

    Menottie, James Louis

    2013-02-26

    Systems for coupling ends of elongated heaters and methods of using such systems to treat a subsurface formation are described herein. A system may include two elongated heaters with an end portion of one heater abutted or near to an end portion of the other heater and a core coupling material. The core coupling material may extend between the two elongated heaters. The elongated heaters may include cores and at least one conductor substantially concentrically surrounds the cores. The cores may have a lower melting point than the conductors. At least one end portion of the conductor may have a beveled edge. The gap formed by the beveled edge may be filled with a coupling material for coupling the one or more conductors. One end portion of at least one core may have a recessed opening and the core coupling material may be partially inside the recessed opening.

  15. 48 CFR 52.208-8 - Required Sources for Helium and Helium Usage Data.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Helium and Helium Usage Data. 52.208-8 Section 52.208-8 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.208-8 Required Sources for Helium and Helium Usage Data. As prescribed in 8.505, insert the following clause: Required Sources for Helium and Helium Usage Data (APR 2002) (a)...

  16. 48 CFR 52.208-8 - Required Sources for Helium and Helium Usage Data.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Helium and Helium Usage Data. 52.208-8 Section 52.208-8 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.208-8 Required Sources for Helium and Helium Usage Data. As prescribed in 8.505, insert the following clause: Required Sources for Helium and Helium Usage Data (APR 2014) (a)...

  17. 48 CFR 52.208-8 - Required Sources for Helium and Helium Usage Data.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Helium and Helium Usage Data. 52.208-8 Section 52.208-8 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.208-8 Required Sources for Helium and Helium Usage Data. As prescribed in 8.505, insert the following clause: Required Sources for Helium and Helium Usage Data (APR 2002) (a)...

  18. 48 CFR 52.208-8 - Required Sources for Helium and Helium Usage Data.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Helium and Helium Usage Data. 52.208-8 Section 52.208-8 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.208-8 Required Sources for Helium and Helium Usage Data. As prescribed in 8.505, insert the following clause: Required Sources for Helium and Helium Usage Data (APR 2002) (a)...

  19. 48 CFR 52.208-8 - Required Sources for Helium and Helium Usage Data.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Helium and Helium Usage Data. 52.208-8 Section 52.208-8 Federal Acquisition Regulations System FEDERAL... Provisions and Clauses 52.208-8 Required Sources for Helium and Helium Usage Data. As prescribed in 8.505, insert the following clause: Required Sources for Helium and Helium Usage Data (APR 2002) (a)...

  20. Antecedents of Continued Usage Intentions of Web-Based Learning Management System in Tanzania

    ERIC Educational Resources Information Center

    Lwoga, Edda Tandi; Komba, Mercy

    2015-01-01

    Purpose: The purpose of this paper is to examine factors that predict students' continued usage intention of web-based learning management systems (LMS) in Tanzania, with a specific focus on the School of Business of Mzumbe University. Specifically, the study investigated major predictors of actual usage and continued usage intentions of…

  1. Polyelectrolyte-diffused zinc phosphate conversion coatings and polyacid coupling primers for corrosion protection of steel and aluminum, and alkali-catalyzed hydrolysis of polyimide-based materials: Final report

    SciTech Connect

    Sugama, T.; Kukacka, L.E.; Carciello, N.R.; Warren, J.B.; Clayton, C.R.

    1989-08-01

    Under US Army Research Office (ARO) sponsorship, Brookhaven National Laboratory (BNL) performed research on three topics: (1) polyelectrolyte-modified zinc phosphate (Zn/center dot/Ph) conversion coatings for the corrosion protection of steel, (2) water-soluble polyacid coupling primers for improving the corrosion resistance and adherence of polymeric paints, and (3) high-temperature lightweight polyimide material systems. In the first topic, it was found that insoluble crystalline zinc phosphate (Zn/center dot/Ph) conversion coatings can be produced on steel surfaces by immersing a surface-cleaned cold-rolled steel substrate into a BNL-developed phosphating solution containing three components, zinc orthophosphate dihydrate (Zn/sub 3/(PO/sub 4/)/sub 2/sup /minus////center dot/2H/sub 2/O), H/sub 3/PO/sub 4/, and water. The major phase in the conversion coating derived from this simple phosphating solution is the same zinc phosphate dihydrate as that used in the converting solution. Referring to the second topic, it was found that the poly(itaconic acid), p(IA), which contains two functional COOH groups located on the same backbone carbon, has potential for use as a water-soluble intermediate coupling primer for polymer adhesive/Al/sub 2/O/sub 3/ adherend joint systems. Emphasis in the third topic was placed on understanding the reaction processes and degradation mechanisms of PI polymers which occur at the interfaces between the PI and inorganic pigments in hydrothermal environments at /ge/150/degree/C.

  2. Materials Control for Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Ferguson, Michael

    2005-01-01

    The distant future of mankind and the ultimate survivability of the human race, as it is known today, will depend on mans' ability to break earthly bonds and establish new territorial positions throughout the universe. Man must therefore be positioned to not only travel to, but also, to readily adapt to numerous and varying environments. For this mass migration across the galaxies nothing is as import to the human race as is NASA's future missions into Low Earth Orbit (LEO), to the moon, and/or Mars. These missions will form the building blocks to eternity for mankind. From these missions, NASA will develop the foundations for these building blocks based on sound engineering and scientific principles, both known and yet to be discovered. The integrity of the program will lead to development, tracking and control of the most basic elements of hardware production: That being development and control of applications of space flight materials. Choosing the right material for design purposes involves many considerations, such as governmental regulations associated with manufacturing operations, both safety of usage and of manufacturing, general material usage requirements, material longevity and performance requirements, material interfacing compatibility and material usage environments. Material performance is subject to environmental considerations in as much as a given material may perform exceptionally well at standard temperatures and pressures while performing poorly under non-standard conditions. These concerns may be found true for materials relative to the extreme temperatures and vacuum gradients of high altitude usage. The only way to assure that flight worthy materials are used in design is through testing. However, as with all testing, it requires both time on schedule and cost to the operation. One alternative to this high cost testing approach is to rely on a materials control system established by NASA. The NASA community relies on the MAPTIS materials

  3. Dark coupling

    SciTech Connect

    Gavela, M.B.; Hernández, D.; Honorez, L. Lopez; Mena, O.; Rigolin, S. E-mail: d.hernandez@uam.es E-mail: omena@ific.uv.es

    2009-07-01

    The two dark sectors of the universe—dark matter and dark energy—may interact with each other. Background and linear density perturbation evolution equations are developed for a generic coupling. We then establish the general conditions necessary to obtain models free from non-adiabatic instabilities. As an application, we consider a viable universe in which the interaction strength is proportional to the dark energy density. The scenario does not exhibit ''phantom crossing'' and is free from instabilities, including early ones. A sizeable interaction strength is compatible with combined WMAP, HST, SN, LSS and H(z) data. Neutrino mass and/or cosmic curvature are allowed to be larger than in non-interacting models. Our analysis sheds light as well on unstable scenarios previously proposed.

  4. Thermoacoustic couple

    DOEpatents

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1983-10-04

    An apparatus and method for determining acoustic power density level and its direction in a fluid using a single sensor are disclosed. The preferred embodiment of the apparatus, which is termed a thermoacoustic couple, consists of a stack of thin, spaced apart polymeric plates, selected ones of which include multiple bimetallic thermocouple junctions positioned along opposite end edges thereof. The thermocouple junctions are connected in series in the nature of a thermopile, and are arranged so as to be responsive to small temperature differences between the opposite edges of the plates. The magnitude of the temperature difference, as represented by the magnitude of the electrical potential difference generated by the thermopile, is found to be directly related to the level of acoustic power density in the gas.

  5. Coupling devices to containers for radioactive material

    SciTech Connect

    Jones, E.L.

    1984-12-04

    A container having a neck is engageable at that neck with a hoist termination. The container is supported at the neck by a ball latch in a shielding flask from which it can be lowered through the base of the flask. The termination is provided with a ball latch releasing rod and single-handed raisable and lowerable sleeve which in the raised position allows engagement of the hoist termination and container neck at screw threads but prevents operation of the releasing rod and in the lowered position allows operation of the release rod but prevents disengagement of the hoist termination and container neck.

  6. How smartphone usage correlates with social anxiety and loneliness

    PubMed Central

    Liu, Xiaoqian; Liu, Xingyun

    2016-01-01

    Introduction: Early detection of social anxiety and loneliness might be useful to prevent substantial impairment in personal relationships. Understanding the way people use smartphones can be beneficial for implementing an early detection of social anxiety and loneliness. This paper examines different types of smartphone usage and their relationships with people with different individual levels of social anxiety or loneliness. Methods: A total of 127 Android smartphone volunteers participated in this study, all of which have agreed to install an application (MobileSens) on their smartphones, which can record user’s smartphone usage behaviors and upload the data into the server. They were instructed to complete an online survey, including the Interaction Anxiousness Scale (IAS) and the University of California Los Angeles Loneliness Scale (UCLA-LS). We then separated participants into three groups (high, middle and low) based on their scores of IAS and UCLA-LS, respectively. Finally, we acquired digital records of smartphone usage from MobileSens and examined the differences in 105 types of smartphone usage behaviors between high-score and low-score group of IAS/UCLA-LS. Results: Individuals with different scores on social anxiety or loneliness might use smartphones in different ways. For social anxiety, compared with users in low-score group, users in high-score group had less number of phone calls (incoming and outgoing) (Mann-Whitney U = 282.50∼409.00, p < 0.05), sent and received less number of text messages in the afternoon (Mann-Whitney U = 391.50∼411.50, p < 0.05), used health & fitness apps more frequently (Mann-Whitney U = 493.00, p < 0.05) and used camera apps less frequently (Mann-Whitney U = 472.00, p < 0.05). For loneliness, users in low-score group, users in high-score group had less number of phone calls (incoming and outgoing) (Mann-Whitney U = 305.00∼407.50, p < 0.05) and used following apps more frequently: health & fitness (Mann-Whitney U

  7. Genome-Wide Analysis of Codon Usage Bias in Epichloë festucae.

    PubMed

    Li, Xiuzhang; Song, Hui; Kuang, Yu; Chen, Shuihong; Tian, Pei; Li, Chunjie; Nan, Zhibiao

    2016-01-01

    Analysis of codon usage data has both practical and theoretical applications in understanding the basics of molecular biology. Differences in codon usage patterns among genes reflect variations in local base compositional biases and the intensity of natural selection. Recently, there have been several reports related to codon usage in fungi, but little is known about codon usage bias in Epichloë endophytes. The present study aimed to assess codon usage patterns and biases in 4870 sequences from Epichloë festucae, which may be helpful in revealing the constraint factors such as mutation or selection pressure and improving the bioreactor on the cloning, expression, and characterization of some special genes. The GC content with 56.41% is higher than the AT content (43.59%) in E. festucae. The results of neutrality and effective number of codons plot analyses showed that both mutational bias and natural selection play roles in shaping codon usage in this species. We found that gene length is strongly correlated with codon usage and may contribute to the codon usage patterns observed in genes. Nucleotide composition and gene expression levels also shape codon usage bias in E. festucae. E. festucae exhibits codon usage bias based on the relative synonymous codon usage (RSCU) values of 61 sense codons, with 25 codons showing an RSCU larger than 1. In addition, we identified 27 optimal codons that end in a G or C. PMID:27428961

  8. Genome-Wide Analysis of Codon Usage Bias in Epichloë festucae

    PubMed Central

    Li, Xiuzhang; Song, Hui; Kuang, Yu; Chen, Shuihong; Tian, Pei; Li, Chunjie; Nan, Zhibiao

    2016-01-01

    Analysis of codon usage data has both practical and theoretical applications in understanding the basics of molecular biology. Differences in codon usage patterns among genes reflect variations in local base compositional biases and the intensity of natural selection. Recently, there have been several reports related to codon usage in fungi, but little is known about codon usage bias in Epichloë endophytes. The present study aimed to assess codon usage patterns and biases in 4870 sequences from Epichloë festucae, which may be helpful in revealing the constraint factors such as mutation or selection pressure and improving the bioreactor on the cloning, expression, and characterization of some special genes. The GC content with 56.41% is higher than the AT content (43.59%) in E. festucae. The results of neutrality and effective number of codons plot analyses showed that both mutational bias and natural selection play roles in shaping codon usage in this species. We found that gene length is strongly correlated with codon usage and may contribute to the codon usage patterns observed in genes. Nucleotide composition and gene expression levels also shape codon usage bias in E. festucae. E. festucae exhibits codon usage bias based on the relative synonymous codon usage (RSCU) values of 61 sense codons, with 25 codons showing an RSCU larger than 1. In addition, we identified 27 optimal codons that end in a G or C. PMID:27428961

  9. Prevalence of Internet and Social Media Usage in Orthopedic Surgery

    PubMed Central

    Curry, Emily; Nguyen, Joseph; Matzkin, Elizabeth

    2014-01-01

    Prior studies in other specialties have shown that social networking and Internet usage has become an increasingly important means of patient communication and referral. The purpose of this study is to evaluate the prevalence of Internet or social media usage in new patients referred to a major academic orthopedics center and to identify new avenues to optimize patient recruitment and communication. New patients were surveyed (n=752) between December 2012 to January 2013 in a major academic orthopaedic center to complete a 15-item questionnaire including social media and Internet usage information. Data was collected for all orthopaedic sub-specialties and statistical analysis was performed. Fifty percent of patients use social networking sites, such as Facebook. Sports medicine patients tend to be higher social networking users (35.9%) relative to other services (9.8-17.9%) and was statistically higher when compared to the joints/tumor service (P<0.0001). Younger age was the biggest indicator predicting the use of social media. Patients that travelled between 120 to 180 miles from the hospital for their visits were significantly more likely to be social media users, as were patients that did research on their condition prior to their new patient appointment. We conclude that orthopedic patients who use social media/Internet are more likely to be younger, researched their condition prior to their appointment and undergo a longer average day’s travel (120-180 miles) to see a physician. In an increasingly competitive market, surgeons with younger patient populations will need to utilize social networking and the Internet to capture new patient referrals. PMID:25317312

  10. Online tables of contents for books: effect on usage*

    PubMed Central

    Morris, Ruth C.

    2001-01-01

    Objectives: To explore whether the presence of online tables of contents (TOC) in an online catalog affects circulation (checkouts and inhouse usage). Two major questions were posed: (1) did the presence of online tables of contents for books increase use, and, (2) if it did, what factors might cause the increase? Method: A randomized and stratified design was used in tracking usage of 3,957 book titles that were previously divided into two groups: one with TOC and one without TOC. Stratification was done for year of imprint, location, subject, previous use, circulating or non-circulating status, and presence of TOC. The use was tracked by the online catalog statistics in the InnoPac online catalog for fourteen months. Results: The study found that tables of contents do increase usage. It also showed a correlation in the size of the effect based on the currency of the titles. In general, even after adjusting for all of the variables (publication date, location, circulation status, subject, and previous use), the odds of a title being used increased by 45% if the titles had online tables of contents, a statistically significant impact at the 0.05 level. Conclusions: This case-control study presents new information about the impact on circulation and inhouse use when tables of contents for books are added to the online catalog record. The study helps to establish the positive role of tables of contents in online catalogs. The research establishes TOC as a major parameter that can be successfully studied using quantitative methods. The study also provides information professionals with some guidance on when enhancement of TOC is likely to be most effective in increasing the use of existing collections. PMID:11209798

  11. Energy usage while maintaining thermal comfort: A case study of a UNT dormitory

    NASA Astrophysics Data System (ADS)

    Gambrell, Dusten

    Campus dormitories for the University of North Texas house over 5500 students per year; each one of them requires certain comfortable living conditions while they live there. There is an inherit amount of money required in order to achieve minimal comfort levels; the cost is mostly natural gas for water and room heating and electricity for cooling, lighting and peripherals. The US Department of Energy has developed several programs to aid in performing energy simulations to help those interested design more cost effective building designs. Energy-10 is such a program that allows users to conduct whole house evaluations by reviewing and altering a few parameters such as building materials, solar heating, energy efficient windows etc. The idea of this project was to recreate a campus dormitory and try to emulate existent energy consumption then try to find ways of lowering that usage while maintaining a high level of personal comfort.

  12. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1998-08-04

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4 C storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4 C for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials. 8 figs.

  13. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOEpatents

    Bitensky, Mark W.; Yoshida, Tatsuro

    1998-01-01

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4.degree. C. storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4.degree. C. for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials.

  14. A PRACTICAL ONTOLOGY FOR THE LARGE-SCALE MODELING OF SCHOLARLY ARTIFACTS AND THEIR USAGE

    SciTech Connect

    RODRIGUEZ, MARKO A.; BOLLEN, JOHAN; VAN DE SOMPEL, HERBERT

    2007-01-30

    The large-scale analysis of scholarly artifact usage is constrained primarily by current practices in usage data archiving, privacy issues concerned with the dissemination of usage data, and the lack of a practical ontology for modeling the usage domain. As a remedy to the third constraint, this article presents a scholarly ontology that was engineered to represent those classes for which large-scale bibliographic and usage data exists, supports usage research, and whose instantiation is scalable to the order of 50 million articles along with their associated artifacts (e.g. authors and journals) and an accompanying 1 billion usage events. The real world instantiation of the presented abstract ontology is a semantic network model of the scholarly community which lends the scholarly process to statistical analysis and computational support. They present the ontology, discuss its instantiation, and provide some example inference rules for calculating various scholarly artifact metrics.

  15. Use of nanofiltration to reduce cooling tower water usage.

    SciTech Connect

    Sanchez, Andres L.; Everett, Randy L.; Jensen, Richard Pearson; Cappelle, Malynda A.; Altman, Susan Jeanne

    2010-09-01

    Nanofiltration (NF) can effectively treat cooling-tower water to reduce water consumption and maximize water usage efficiency of thermoelectric power plants. A pilot is being run to verify theoretical calculations. A side stream of water from a 900 gpm cooling tower is being treated by NF with the permeate returning to the cooling tower and the concentrate being discharged. The membrane efficiency is as high as over 50%. Salt rejection ranges from 77-97% with higher rejection for divalent ions. The pilot has demonstrated a reduction of makeup water of almost 20% and a reduction of discharge of over 50%.

  16. Stable Water Usage, But Some Groundwater Concerns, USGS Report Indicates

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2004-03-01

    Water use in the United States has remained fairly stable since 1985, according to an 11 March report by the U.S. Geological Survey. The report, which estimates water use for the year 2000-the most recent available data-indicates that Americans used an estimated 408 billion gallons of water per day, an amount the agency said would fill 8 billion bathtubs daily. The usage also translates into 1,430 gallons used per person per day, when including all uses, including electric power generation, irrigation, and personal use.

  17. The Situation of ICT Usage in Nagoya University Law School

    NASA Astrophysics Data System (ADS)

    Kaneko, Daisuke; Sugawara, Ikuo

    Since the introduction of a new legal education system in 2004, some of Japanese legal educational institutions have changed into professional schools which names are Law School. These law schools are required not only theoretical studies but also professional skills training. Law students, however, have limited time to complete this agenda, so law professors have to teach courses effectively. In this paper, the authors present the situation of ICT usage in Nagoya University Law School as a case study to describe and to critique systems to support theoretical studies and professional skills training.

  18. Usage of fly ash as a coal desulphurization reagent

    SciTech Connect

    Yaman, S.; Kuecuekbayrak, S.

    1996-12-31

    This paper covers the direct usage of fly ash to remove sulphur from coal. Experiments were carried out on a high sulphur Turkish lignite. 5 g of fly ash was extracted in 200 ml of water under pressure and the dilute solution containing water extractable parts of fly ash was used as desulphurization reagent. Oxygen pressure was created over desulphurization medium during the extraction period by which dissolved oxygen was concentrated in the solution. Effects of temperature, partial pressure of oxygen, and time were investigated in the ranges of 403--498 K, 0.0--1.5 MPa and 15--90 min, respectively.

  19. Quantifying Wikipedia Usage Patterns Before Stock Market Moves

    NASA Astrophysics Data System (ADS)

    Moat, Helen Susannah; Curme, Chester; Avakian, Adam; Kenett, Dror Y.; Stanley, H. Eugene; Preis, Tobias

    2013-05-01

    Financial crises result from a catastrophic combination of actions. Vast stock market datasets offer us a window into some of the actions that have led to these crises. Here, we investigate whether data generated through Internet usage contain traces of attempts to gather information before trading decisions were taken. We present evidence in line with the intriguing suggestion that data on changes in how often financially related Wikipedia pages were viewed may have contained early signs of stock market moves. Our results suggest that online data may allow us to gain new insight into early information gathering stages of decision making.

  20. DC Fast Charger Usage in the Pacific Northwest

    SciTech Connect

    Salisbury, Shawn; Smart, John

    2015-02-01

    This document will describe the use of a number of Direct Current Fast Charging Stations throughout Washington and Oregon as a part of of the West Coast Electric Highway. It will detail the usage frequency and location of the charging stations INL has data from. It will also include aggregated data from hundreds of privately owned vehicles that were enrolled in the EV Project regarding driving distance when using one of the West Coast Electric Highway fast chargers. This document is a white paper that will be published on the INL AVTA website.