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Sample records for active gain material

  1. Active Enhancement of Slow Light Based on Plasmon-Induced Transparency with Gain Materials.

    Science.gov (United States)

    Zhang, Zhaojian; Yang, Junbo; He, Xin; Han, Yunxin; Zhang, Jingjing; Huang, Jie; Chen, Dingbo; Xu, Siyu

    2018-06-03

    As a plasmonic analogue of electromagnetically induced transparency (EIT), plasmon-induced transparency (PIT) has drawn more attention due to its potential of realizing on-chip sensing, slow light and nonlinear effect enhancement. However, the performance of a plasmonic system is always limited by the metal ohmic loss. Here, we numerically report a PIT system with gain materials based on plasmonic metal-insulator-metal waveguide. The corresponding phenomenon can be theoretically analyzed by coupled mode theory (CMT). After filling gain material into a disk cavity, the system intrinsic loss can be compensated by external pump beam, and the PIT can be greatly fueled to achieve a dramatic enhancement of slow light performance. Finally, a double-channel enhanced slow light is introduced by adding a second gain disk cavity. This work paves way for a potential new high-performance slow light device, which can have significant applications for high-compact plasmonic circuits and optical communication.

  2. Slow and stopped light in active gain composite materials of metal nanoparticles. Ultralarge group index-bandwidth product predicted

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwang-Hyon; Choe, Song-Hyok [Institute of Lasers, State Academy of Sciences, Unjong District, Pyongyang (Korea, Democratic People' s Republic of)

    2017-08-15

    Chip-compatible slow light devices with large group index-bandwidth products and low losses are of great interest in the community of modern photonics. In this work, active gain materials containing metal nanoparticles are proposed as the slow and stopped light materials. Gain-assisted high field enhancement in metal nanoparticles and the resultant strong dispersion lead to such phenomena. From the Maxwell-Garnett model, it is revealed that the metal nanocomposite exhibits the infinitely large group index when the gain of the host medium and the filling factor of metal nanoparticles satisfy a critical condition. For the gain of the host above the critical value, one can observe slowing down effect with amplification of light pulses. Significantly large group index-bandwidth products, which vary from a few to several thousand or even infinity depending on the gain value of the host medium, have been numerically predicted in active silica glasses containing spheroidal metal nanoparticles, as examples. The proposed scheme inherently provides the widely varying operating spectral range by changing the aspect ratio of metal nanoparticles and chip-compatibility with low cost. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. The Study of Electromagnetic Wave Propogation in Photonic Crystals Via Planewave Based Transfer (Scattering) Matrix Method with Active Gain Material Applications

    Energy Technology Data Exchange (ETDEWEB)

    LI, Ming [Iowa State Univ., Ames, IA (United States)

    2007-01-01

    In this dissertation, a set of numerical simulation tools are developed under previous work to efficiently and accurately study one-dimensional (1D), two-dimensional(2D), 2D slab and three-dimensional (3D) photonic crystal structures and their defects effects by means of spectrum (transmission, reflection, absorption), band structure (dispersion relation), and electric and/or magnetic fields distribution (mode profiles). Furthermore, the lasing property and spontaneous emission behaviors are studied when active gain materials are presented in the photonic crystal structures. Various physical properties such as resonant cavity quality factor, waveguide loss, propagation group velocity of electromagnetic wave and light-current curve (for lasing devices) can be obtained from the developed software package.

  4. The study of electromagnetic wave propagation in photonic crystals via planewave based transfer (scattering) matrix method with active gain material applications

    Science.gov (United States)

    Li, Ming

    In this dissertation, a set of numerical simulation tools are developed under previous work to efficiently and accurately study one-dimensional (1D), two-dimensional (2D), 2D slab and three-dimensional (3D) photonic crystal structures and their defects effects by means of spectrum (transmission, reflection, absorption), band structure (dispersion relation), and electric and/or magnetic fields distribution (mode profiles). Further more, the lasing property and spontaneous emission behaviors are studied when active gain materials are presented in the photonic crystal structures. First, the planewave based transfer (scattering) matrix method (TMM) is described in every detail along with a brief review of photonic crystal history (Chapter 1 and 2). As a frequency domain method, TMM has the following major advantages over other numerical methods: (1) the planewave basis makes Maxwell's Equations a linear algebra problem and there are mature numerical package to solve linear algebra problem such as Lapack and Scalapack (for parallel computation). (2) Transfer (scattering) matrix method make 3D problem into 2D slices and link all slices together via the scattering matrix (S matrix) which reduces computation time and memory usage dramatically and makes 3D real photonic crystal devices design possible; and this also makes the simulated domain no length limitation along the propagation direction (ideal for waveguide simulation). (3) It is a frequency domain method and calculation results are all for steady state, without the influences of finite time span convolution effects and/or transient effects. (4) TMM can treat dispersive material (such as metal at visible light) naturally without introducing any additional computation; and meanwhile TMM can also deal with anisotropic material and magnetic material (such as perfectly matched layer) naturally from its algorithms. (5) Extension of TMM to deal with active gain material can be done through an iteration procedure with gain

  5. Active Microwave Metamaterials Incorporating Ideal Gain Devices

    Directory of Open Access Journals (Sweden)

    Hao Xin

    2010-12-01

    Full Text Available Incorporation of active devices/media such as transistors for microwave and gain media for optics may be very attractive for enabling desired low loss and broadband metamaterials. Such metamaterials can even have gain which may very well lead to new and exciting physical phenomena. We investigate microwave composite right/left-handed transmission lines (CRLH-TL incorporating ideal gain devices such as constant negative resistance. With realistic lumped element values, we have shown that the negative phase constant of this kind of transmission lines is maintained (i.e., left-handedness kept while gain can be obtained (negative attenuation constant of transmission line simultaneously. Possible implementation and challenging issues of the proposed active CRLH-TL are also discussed.

  6. Slow-light-enhanced gain in active photonic crystal waveguides

    DEFF Research Database (Denmark)

    Ek, Sara; Hansen, Per Lunnemann; Chen, Yaohui

    2014-01-01

    Passive photonic crystals have been shown to exhibit a multitude of interesting phenomena, including slow-light propagation in line-defect waveguides. It was suggested that by incorporating an active material in the waveguide, slow light could be used to enhance the effective gain of the material......, which would have interesting application prospects, for example enabling ultra-compact optical amplifiers for integration in photonic chips. Here we experi- mentally investigate the gain of a photonic crystal membrane structure with embedded quantum wells. We find that by solely changing the photonic...... crystal structural parameters, the maximum value of the gain coefficient can be increased compared with a ridge waveguide structure and at the same time the spectral position of the peak gain be controlled. The experimental results are in qualitative agreement with theory and show that gain values similar...

  7. Experience gained with Euratom's nuclear materials accounting and reporting system

    International Nuclear Information System (INIS)

    Schmitt, M.; Kschwendt, H.; Maxwell, A.G.; Littlejohn, M.

    1979-01-01

    The entry into force of the Verification Agreement in early 1977, linked to the wish to update the old Euratom System created in 1959, required that a new Euratom system (Community Regulation) be established. The main aspects of this new system, together with the practical experience gained in one and a half years operation, are presented. Certain basic accounting principles incorporated in the Euratom system, which are somewhat different from IAEA principles, are discussed in detail. This includes the notion of accounting date, some correction procedure aspects as well as the continuous updating of the book inventory to the physical reality in form of inventory changes. The effect of these differences when comparing IAEA and Euratom data is also mentioned. Furthermore, certain of the verifications carried out routinely on the operator's reports as well as on the reports submitted by Euratom to IAEA, are described and quantifications are given. Some mention is also made of areas where Euratom's role goes beyond that of the IAEA, i.e. the reporting implications of accounting for material by origin and control of particular use of the materials as well as verification of ore production and processing activities. Finally, improvements and simplifications concerning reports to the IAEA are proposed. (author)

  8. Material gain: bednets treated with insecticides improve the lives of ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-07-15

    ... 700 mosquito nets each day, marketed under brand names such as "Health Net" and ... Material gain: bednets treated with insecticides improve the lives of Tanzanians. July 15, 2011. Image ... The kit is one of the key elements of PSI's Social Marketing of ... The national strategy will work to change this by involving the full ...

  9. Light propagation in composite materials with gain layers

    International Nuclear Information System (INIS)

    Dorofeenko, Aleksandr V; Zyablovsky, A A; Pukhov, Aleksandr A; Lisyansky, A A; Vinogradov, Aleksei P

    2012-01-01

    Light propagation through a single gain layer and a multilayer system with gain layers is studied. Results obtained using the Fresnel formulas, Airy's series summation, and the numerical solution of the nonlinear Maxwell-Bloch equations by the finite difference time domain (FDTD) method are analyzed and compared. Normal and oblique propagation of a wave through a gain layer and a slab of a photonic crystal are examined. For the latter problem, the gain line may be situated in either the pass or stop band of the photonic crystal. It is shown that the monochromatic plane-wave approximation is generally inapplicable for active media, because it leads to results that violate causality. But the problem becomes physically meaningful and correct results can be obtained for all three approaches once the structure of the wavefront and the finite aperture of the beam are taken into account. (reviews of topical problems)

  10. Nonlinear Gain Saturation in Active Slow Light Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Chen, Yaohui; Mørk, Jesper

    2013-01-01

    We present a quantitative three-dimensional analysis of slow-light enhanced traveling wave amplification in an active semiconductor photonic crystal waveguides. The impact of slow-light propagation on the nonlinear gain saturation of the device is investigated.......We present a quantitative three-dimensional analysis of slow-light enhanced traveling wave amplification in an active semiconductor photonic crystal waveguides. The impact of slow-light propagation on the nonlinear gain saturation of the device is investigated....

  11. Weight gain, physical activity and dietary changes during the seven ...

    African Journals Online (AJOL)

    Objective: The objective of the study was to assess weight gain, physical activity and dietary changes during the first year of university life in Malawi. Setting: The setting was Bunda College of Agriculture, University of Malawi. Subjects: The subjects were first-year students (n = 47) enrolled for the 2008/2009 academic year.

  12. Active rc filter permits easy trade-off of amplifier gain and sensitivity to gain

    Science.gov (United States)

    Kerwin, W. J.; Shaffer, C. V.

    1968-01-01

    Passive RC network was designed with zeros of transmission in the right half of the complex frequency plane in the feedback loop of a simple negative-gain amplifier. The proper positioning provides any desired trade-off between amplifier gain and sensitivity to amplifier gain.

  13. Assessment of physical activity among pregnant women in context of weight gain in pregnancy

    Directory of Open Access Journals (Sweden)

    Martyna Mączka

    2017-06-01

    Optimal physical activity from walking is associated with lower body weight gains compared to stimulated physical activity of Pilates, which is not associated with weight gain. The more a women walk, the less weight gain they have.

  14. Activated carbon material

    International Nuclear Information System (INIS)

    Evans, A.G.

    1978-01-01

    Activated carbon particles for use as iodine trapping material are impregnated with a mixture of selected iodine and potassium compounds to improve the iodine retention properties of the carbon. The I/K ratio is maintained at less than about 1 and the pH is maintained at above about 8.0. The iodine retention of activated carbon previously treated with or coimpregnated with triethylenediamine can also be improved by this technique. Suitable flame retardants can be added to raise the ignition temperature of the carbon to acceptable standards

  15. Cosmogenic activation of materials

    Science.gov (United States)

    Cebrián, Susana

    2017-10-01

    Experiments looking for rare events like the direct detection of dark matter particles, neutrino interactions or the nuclear double beta decay are operated deep underground to suppress the effect of cosmic rays. But, the production of radioactive isotopes in materials due to previous exposure to cosmic rays is a hazard when ultra-low background conditions are required. In this context, the generation of long-lived products by cosmic nucleons has been studied for many detector media and for other materials commonly used. Here, the main results obtained on the quantification of activation yields on the Earth’s surface will be summarized, considering both measurements and calculations following different approaches. The isotope production cross-sections and the cosmic ray spectrum are the two main ingredients when calculating this cosmogenic activation; the different alternatives for implementing them will be discussed. Activation that can take place deep underground mainly due to cosmic muons will be briefly commented too. Presently, the experimental results for the cosmogenic production of radioisotopes are scarce and discrepancies between different calculations are important in many cases, but the increasing interest on this background source which is becoming more and more relevant can help to change this situation.

  16. Modulational-instability gain bands in quasi-phase-matched materials

    International Nuclear Information System (INIS)

    Corney, J.F.; Bang, O.

    2002-01-01

    Full text: Quadratically nonlinear materials are of significant technological interest in optics because of their strong and fast cascaded nonlinearities, which are accessed most efficiently with quasi-phase-matching (QPM) techniques. We study the gain spectra of modulational instabilities (Ml) in quadratic materials where the linear and nonlinear properties are modulated with QPM gratings. The periods and intensity-dependence of the Ml can now be measured in the laboratory. Using an exact Floquet theory, we find that novel low- and high-frequency bands appear in the gain spectrum (gain versus transverse spatial frequency). The high-frequency gain bands are a general feature of gain spectra for QPM gratings. They form part of an extensive series of bands that correspond to Ml in the non-phase-matched, quickly varying components of the fields. The low-frequency bands correspond to Ml in the phase-matched DC components of the fields and are accurately predicted by a simple average theory. This theory includes the effect of the quickly varying components as induced cubic terms, which can be strong enough to suppress the low-frequency bands, in which case dark solitons and other broad beams may be effectively stable, since the high-frequency bands are typically small

  17. Material properties in complement activation

    DEFF Research Database (Denmark)

    Moghimi, S. Moein; Andersen, Alina Joukainen; Ahmadvand, Davoud

    2011-01-01

    activation differently and through different sensing molecules and initiation pathways. The importance of material properties in triggering complement is considered and mechanistic aspects discussed. Mechanistic understanding of complement events could provide rational approaches for improved material design...

  18. Artificial Material Integrated Ultra-wideband Tapered Slot Antenna for Gain Enhancement with Band Notch Characteristics

    Directory of Open Access Journals (Sweden)

    R. Singha

    2018-04-01

    Full Text Available The gain of the ultra-wideband tapered slot antenna (TSA is enhanced by using broadband artificial material with band notch characteristics. The proposed artificial material unit cell is designed by fabricating non-resonant three S-shaped parallel metallic line on single side of the dielectric substrate which provides a longer current path compared to the parallel-line structure. The proposed S-shaped structure is printed on the top side of the tapered slot antenna in the extended substrate periodically. The effective refractive index of the artificial material is lower than antenna substrate and phase velocity in the region of artificial material is much higher than the other region. Therefore, the proposed artificial material acts like a beam focusing lens. The band notch at 5.5 GHz is achieved by creating a split ring resonator (SRR slot near the balun. The basic and artificial material loaded TSAs are fabricated and the measurement results show that the gain of the basic antenna has been increased by 1.6 dBi. At the same time, the proposed antenna achieves a VSWR below 2 from 3 to 11 GHz except at 5.5 GHz with a notch band from 5.1 to 5.8 GHz for band rejection of wireless local area network (WLAN application.

  19. Active metamaterial: Gain and stability, and microfluidic chip for THz cell spectroscopy

    Science.gov (United States)

    Tang, Qi

    Metamaterials are artificially designed composite materials which can exhibit unique and unusual properties such as the negative refractive index, negative phase velocity, etc. The concept of metamaterials becomes prevalent in the electromagnetic society since the first experimental implementation in the early 2000s. Many fascinated potential applications, e.g. super lens, invisibility cloaking, and novel antennas that are electrically small, have been proposed based on metamaterials. However, most of the applications still remain in theory and are not suitable for practical applications mainly due to the intrinsic loss and narrow bandwidth (large dispersion) determined by the fundamental physics of metamaterials. In this dissertation, we incorporate active gain devices into conventional passive metamaterials to overcome loss and even provide gain. Two types of active gain negative refractive index metamaterials are proposed, designed and experimentally demonstrated, including an active composite left-/right-handed transmission line and an active volumetric metamaterial. In addition, we investigate the non-Foster circuits for broadband matching of electrically small antennas. A rigorous way of analyzing the stability of non-Foster circuits by normalized determinant function is proposed. We study the practical factors that may affect the stability of non-Foster circuits, including the device parasitics, DC biasing, layouts and load impedance. A stable floating negative capacitor is designed, fabricated and tested. Moreover, it is important to resolve the sign of refractive index for active gain media which can be quite challenging. We investigate the analytical solution of a gain slab system, and apply the Nyquist criterion to analyze the stability of a causal gain medium. We then emphasize that the result of frequency domain simulation has to be treated with care. Lastly, this dissertation discusses another interesting topic about THz spectroscopy of live cells

  20. Propagation of Gaussian Beams through Active GRIN Materials

    International Nuclear Information System (INIS)

    Gomez-Varela, A I; Flores-Arias, M T; Bao-Varela, C; Gomez-Reino, C; De la Fuente, X

    2011-01-01

    We discussed light propagation through an active GRIN material that exhibits loss or gain. Effects of gain or loss in GRIN materials can be phenomenologically taken into account by using a complex refractive index in the wave equation. This work examines the implication of using a complex refractive index on light propagation in an active GRIN material illuminated by a non-uniform monochromatic wave described by a Gaussian beam. We analyze how a Gaussian beam is propagated through the active material in order to characterize it by the beam parameters and the transverse irradiance distribution.

  1. 20 CFR 416.972 - What we mean by substantial gainful activity.

    Science.gov (United States)

    2010-04-01

    ... INCOME FOR THE AGED, BLIND, AND DISABLED Determining Disability and Blindness Substantial Gainful... consider activities like taking care of yourself, household tasks, hobbies, therapy, school attendance...

  2. Weight gain, physical activity and dietary changes during the seven ...

    African Journals Online (AJOL)

    2011-06-06

    Jun 6, 2011 ... Department of Home Economics and Human Nutrition, Faculty of Agriculture, Bunda ... and medium-income countries can implement strategies, including ..... engage in more physical activity such as sport as a result of having.

  3. Hierarchical modeling of active materials

    International Nuclear Information System (INIS)

    Taya, Minoru

    2003-01-01

    Intelligent (or smart) materials are increasingly becoming key materials for use in actuators and sensors. If an intelligent material is used as a sensor, it can be embedded in a variety of structure functioning as a health monitoring system to make their life longer with high reliability. If an intelligent material is used as an active material in an actuator, it plays a key role of making dynamic movement of the actuator under a set of stimuli. This talk intends to cover two different active materials in actuators, (1) piezoelectric laminate with FGM microstructure, (2) ferromagnetic shape memory alloy (FSMA). The advantage of using the FGM piezo laminate is to enhance its fatigue life while maintaining large bending displacement, while that of use in FSMA is its fast actuation while providing a large force and stroke capability. Use of hierarchical modeling of the above active materials is a key design step in optimizing its microstructure for enhancement of their performance. I will discuss briefly hierarchical modeling of the above two active materials. For FGM piezo laminate, we will use both micromechanical model and laminate theory, while for FSMA, the modeling interfacing nano-structure, microstructure and macro-behavior is discussed. (author)

  4. Material science experience gained from the space nuclear rocket program: Insulators

    International Nuclear Information System (INIS)

    Wagner, P.

    1992-07-01

    Although Rover reactors are viewed as the ultimate in high-temperature operating systems, many of the materials used in these reactors (for example, support rods, control drums, and the reflector) have to be held at relatively low temperatures while the reactor operates, in order to maintain their structural integrity. Thus the insulators needed to separate these temperature domains are crucial to the reactor's ultimate operating times and temperatures. All of the reactors that were tested used pyrolytic graphite as the primary insulator. However, it had been long planned to replace the graphite with zirconium carbide and a lengthy and intensive effort to develop the zirconium carbide insulators had been made at the time Rover was terminated. This report details research and development and the experience we gained with both these insulator materials

  5. 26 CFR 7.105-2 - Substantial gainful activity.

    Science.gov (United States)

    2010-04-01

    ... performed for remuneration or profit). (c) General rules. (1) Full-time work under competitive circumstances...'s rate of pay in the former position. It is immaterial that the new work activity is less demanding... § 7.105-1, prescribes rules for determining whether a taxpayer has the ability to engage in...

  6. The ICAP Active Learning Framework Predicts the Learning Gains Observed in Intensely Active Classroom Experiences

    Directory of Open Access Journals (Sweden)

    Benjamin L. Wiggins

    2017-05-01

    Full Text Available STEM classrooms (science, technology, engineering, and mathematics in postsecondary education are rapidly improved by the proper use of active learning techniques. These techniques occupy a descriptive spectrum that transcends passive teaching toward active, constructive, and, finally, interactive methods. While aspects of this framework have been examined, no large-scale or actual classroom-based data exist to inform postsecondary education STEM instructors about possible learning gains. We describe the results of a quasi-experimental study to test the apex of the ICAP framework (interactive, constructive, active, and passive in this ecological classroom environment. Students in interactive classrooms demonstrate significantly improved learning outcomes relative to students in constructive classrooms. This improvement in learning is relatively subtle; similar experimental designs without repeated measures would be unlikely to have the power to observe this significance. We discuss the importance of seemingly small learning gains that might propagate throughout a course or departmental curriculum, as well as improvements with the necessity for faculty to develop and implement similar activities.

  7. Elaboration and optimization of tellurite-based materials for raman gain application

    Science.gov (United States)

    Guery, Guillaume

    Tellurite-based oxide glasses have been investigated as promising materials for Raman gain applications, due to their good linear and nonlinear optical properties and their wide transparency windows in the near- and midwave infrared spectral region. Furthermore, their interesting thermal properties, i.e. low glass transition temperature and ability to be drawn into optical fibers, make tellurite-based glasses excellent candidates for optical fiber amplifiers. The estimation of the strength and spectral distribution of Raman gain in materials is commonly approximated from the spontaneous Raman scattering cross-section measurement. For development of tellurite-based glasses as Raman amplifiers, understanding the relationship between glass structure, vibrational response, and nonlinear optical properties (NLO) represents a key point. This dissertation provides an answer to the fundamental question of the PhD study: "What is the impact of the glass structure on Raman gain properties of tellurite glasses?" This dissertation summarizes findings on different tellurite-based glass families: the TeO2-TaO5/2-ZnO, TeO2-BiO 3/2-ZnO and TeO2-NbO5/2 glass networks. The influence of glass modifiers has been shown on the glass' properties. Introduction of tantalum oxide or zinc oxide has been shown to increase the glass' stability against crystallization, quantified by DeltaT, where DeltaT = Tx -Tg. Added to the variation of the glass viscosity, this attribute is critical in fabricating optical fibers and for the use of these materials in fiber-based Raman gain applications. The role of ZnO in the tellurite network and the mechanism for structural modification has been determined. This addition results in not only the largest DeltaT reported for these highly nonlinear glasses to date, but coincides with a commensurate decrease of the refractive index. A hydroxyl purification has been developed that when employed, resulted in high purity preform materials exhibiting a limited

  8. Habitual active transport, TV viewing and weight gain: a four year follow-up study.

    Science.gov (United States)

    Ding, Ding; Sugiyama, Takemi; Owen, Neville

    2012-01-01

    To examine the associations of TV viewing time and domain-specific physical activity with weight change; to determine whether domain-specific physical activity moderates the potential association of TV viewing time with weight change. We used four-year longitudinal data (baseline: 2003-2004, follow-up: 2007-2008) on 969 adults from selected neighborhoods in Adelaide, Australia (Age: 48.6 ± 10.6 years, 61% females). Mixed models examined four-year weight change as the dependent variable, with TV viewing time, habitual transport and past week domain-specific physical activity at baseline as independent variables. On average, participants gained 1.6 kg over four years. TV viewing time at baseline was positively associated with weight gain at follow-up. Each additional hour of TV viewing was associated with 0.24-0.27 kg of extra weight gain. This relationship was not moderated by recent recall of transport, leisure-time, and occupational physical activity, but was moderated by habitual transport: an additional hour of TV viewing time at baseline was significantly associated with an extra weight gain of 0.65 kg at follow-up among those who were inactive in everyday transport; TV time was not significantly associated with weight change among those who were regularly active in transport. Habitual active transport may protect adults against risk of weight gain associated with prolonged TV viewing time. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Optical gain of LaF3:Nd nanoparticle doped polymers for active integrated optical devices

    NARCIS (Netherlands)

    Stouwdam, J.W.; Klunder, D.J.W.; Borreman, A.; Diemeer, Mart; Worhoff, Kerstin; Driessen, A.; de Ridder, R.M.; de Ridder, R.M; Altena, G; Altena, G.; Geuzebroek, D.H.; Dekker, R; Dekker, R.

    2003-01-01

    We report on rare earth doped LaF3 nanoparticles dispersed in PMMA and SU-8 photosensitive polymers. We observed optical gain after we applied these materials for waveguides. Experimental results on various samples will be discussed. We theoretically discuss the improvements that can be obtained and

  10. Low activation materials for fusion

    International Nuclear Information System (INIS)

    Rowcliffe, A.F.; Bloom, E.E.; Doran, D.G.; Smith, D.L.; Reuther, T.C.

    1988-01-01

    The viability of fusion as a future energy source may eventually be determined by safety and environmental factors. Control of the induced radioactivity characteristics of the materials used in the first wall and blanket could have a major favorable impact on these issues. In the United States, materials program efforts are focused on developing new structural alloys with radioactive decay characteristics which would greatly simplify long-term waste disposal of reactor components. A range of alloy systems is being explored in order to maintain the maximum number of design options. Significant progress has been made, and it now appears probable that reduced-activation engineering alloys with properties at least equivalent to conventional alloys can be successfully developed and commercialized. 10 refs., 1 fig

  11. Years of life gained due to leisure-time physical activity in the U.S.

    Science.gov (United States)

    Janssen, Ian; Carson, Valerie; Lee, I-Min; Katzmarzyk, Peter T; Blair, Steven N

    2013-01-01

    Physical inactivity is an important modifiable risk factor for noncommunicable disease. The degree to which physical activity affects the life expectancy of Americans is unknown. This study estimated the potential years of life gained due to leisure-time physical activity in the U.S. Data from the National Health and Nutrition Examination Survey (2007-2010); National Health Interview Study mortality linkage (1990-2006); and U.S. Life Tables (2006) were used to estimate and compare life expectancy at each age of adult life for inactive (no moderate to vigorous physical activity); somewhat-active (some moderate to vigorous activity but active (≥ 500 MET minutes/week of moderate to vigorous activity) adults. Analyses were conducted in 2012. Somewhat-active and active non-Hispanic white men had a life expectancy at age 20 years that was ~2.4 years longer than that for the inactive men; this life expectancy advantage was 1.2 years at age 80 years. Similar observations were made in non-Hispanic white women, with a higher life expectancy within the active category of 3.0 years at age 20 years and 1.6 years at age 80 years. In non-Hispanic black women, as many as 5.5 potential years of life were gained due to physical activity. Significant increases in longevity were also observed within somewhat-active and active non-Hispanic black men; however, among Hispanics the years-of-life-gained estimates were not significantly different from 0 years gained. Leisure-time physical activity is associated with increases in longevity. Copyright © 2013 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  12. Years of Life Gained Due to Leisure-Time Physical Activity in the United States

    Science.gov (United States)

    Janssen, Ian; Carson, Valerie; Lee, I-Min; Katzmarzyk, Peter T.; Blair, Steven N.

    2013-01-01

    Background Physical inactivity is an important modifiable risk factor for non-communicable disease. The degree to which physical activity affects the life expectancy of Americans is unknown. This study estimated the potential years of life gained due to leisure-time physical activity across the adult lifespan in the United States. Methods Data from the National Health and Nutrition Examination Survey (2007–2010), National Health Interview Study mortality linkage (1990–2006), and US Life Tables (2006) were used to estimate and compare life expectancy at each age of adult life for inactive (no moderate-to-vigorous physical activity), somewhat active (some moderate-to-vigorous activity but active (≥500 metabolic equivalent min/week of moderate-to-vigorous activity) adults. Analyses were conducted in 2012. Results Somewhat active and active non-Hispanic white men had a life expectancy at age 20 that was around 2.4 years longer than the inactive men; this life expectancy advantage was 1.2 years at age 80. Similar observations were made in non-Hispanic white women, with a higher life expectancy within the active category of 3.0 years at age 20 and 1.6 years at age 80. In non-Hispanic black women, as many as 5.5 potential years of life were gained due to physical activity. Significant increases in longevity were also observed within somewhat active and active non-Hispanic black men; however, among Hispanics the years of life gained estimates were more variable and not significantly different from 0 years gained. Conclusions Leisure-time physical activity is associated with increases in longevity in the United States. PMID:23253646

  13. Active mode-locking of mid-infrared quantum cascade lasers with short gain recovery time.

    Science.gov (United States)

    Wang, Yongrui; Belyanin, Alexey

    2015-02-23

    We investigate the dynamics of actively modulated mid-infrared quantum cascade lasers (QCLs) using space- and time-domain simulations of coupled density matrix and Maxwell equations with resonant tunneling current taken into account. We show that it is possible to achieve active mode locking and stable generation of picosecond pulses in high performance QCLs with a vertical laser transition and a short gain recovery time by bias modulation of a short section of a monolithic Fabry-Perot cavity. In fact, active mode locking in QCLs with a short gain recovery time turns out to be more robust to the variation of parameters as compared to previously studied lasers with a long gain recovery time. We investigate the effects of spatial hole burning and phase locking on the laser output.

  14. Energy expenditure, spontaneous physical activity and with weight gain in kidney transplant recipients.

    Science.gov (United States)

    Heng, Anne-Elisabeth; Montaurier, Christophe; Cano, Noël; Caillot, Nicolas; Blot, A; Meunier, Nathalie; Pereira, Bruno; Marceau, Geoffroy; Sapin, Vincent; Jouve, Christelle; Boirie, Yves; Deteix, Patrice; Morio, Beatrice

    2015-06-01

    Alterations in energy metabolism could trigger weight gain after renal transplantation. Nineteen transplanted non-diabetic men, 53 ± 1.6 years old, receiving calcineurin inhibitors but no corticosteroids were studied. They were compared with nine healthy men matched for height, age and lean body mass. Daily energy expenditure and its components (sleeping, basal and absorptive metabolic rates) were analyzed for 24 h in calorimetric chambers and for 4 days in free living conditions using calibrated accelerometry. Other variables known to influence energy expenditure were assessed: body composition, physical activity, 4-day food intake, drug consumption, serum C-reactive protein, interleukin-6, thyroid and parathyroid hormones, and epinephrine. Transplant recipients who gained more than 5% body weight after transplantation (n = 11, +11.0 ± 1.5 kg) were compared with those who did not (n = 8) and with the controls. Weight gain compared with non-weight gain patients and controls exhibited higher fat mass without change in lean body mass. Daily, sleeping and resting energy expenditure adjusted for lean body mass was significantly higher in non-weight gain (167.1 ± 4.2 kJ/kg/lean body mass/24 h, P controls (146.1 ± 4.6). Weight gain compared with controls and non-weight gain subjects had lower free living physical activity and a higher consumption of antihypertensive drugs and β-blockers. After kidney transplantation, weight gain patients were characterized by lower adjusted energy expenditure, reduced spontaneous physical activity but a more sedentary life style and a trend toward a higher energy intake explaining the reason they gained weight. The nWG KTR had increased resting and sleeping EE which protected them from weight gain. Such hypermetabolism was also observed in 24-h EE measurements. By comparison with the nWG patients, the WG transplant recipients were characterized by higher β-blocker consumption. These data could be helpful in the prevention of weight

  15. Modeling of gain saturation effects in active semiconductor photonic crystal waveguides

    DEFF Research Database (Denmark)

    Chen, Yaohui; Mørk, Jesper

    2012-01-01

    In this paper, we present a theoretical analysis of slow-light enhanced light amplification in an active semiconductor photonic crystal line defect waveguide. The impact of enhanced light-matter interactions on carrier-depletion-induced modal gain saturation is investigated.......In this paper, we present a theoretical analysis of slow-light enhanced light amplification in an active semiconductor photonic crystal line defect waveguide. The impact of enhanced light-matter interactions on carrier-depletion-induced modal gain saturation is investigated....

  16. High Voltage Gain Dual Active Bridge Converter with an Extended Operation Range for Renewable Energy Systems

    DEFF Research Database (Denmark)

    Zhang, Zhe; Tomas Manez, Kevin; Yudi, Xiao

    2018-01-01

    Bridge (P2DAB) converter, i.e. low-voltage (LV) side parallel and high-voltage (HV) side series, is proposed to achieve high voltage gain and low current stress over switching devices and transformer windings. Given the unmodified P2DAB power stage, by regulating the phase-shift angle between......Developing bidirectional dc-dc converters has become a critical research topic and gains more and more attention in recent years due to the extensive applications of smart grids with energy storages, hybrid and electrical vehicles and dc microgrids. In this paper, a Partial Parallel Dual Active...... the paralleled active bridges, the power equations and voltage gain are then modified, and therefore the operation range can be extended effectively. The operating principles of the proposed converter and its power characteristics under various operation modes are studied, and the design constraints...

  17. External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE

    Science.gov (United States)

    Zahodne, Laura B.; Meyer, Oanh L.; Choi, Eunhee; Thomas, Michael L.; Willis, Sherry L.; Marsiske, Michael; Gross, Alden L.; Rebok, George W.; Parisi, Jeanine M.

    2015-01-01

    Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. PMID:26237116

  18. External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE.

    Science.gov (United States)

    Zahodne, Laura B; Meyer, Oanh L; Choi, Eunhee; Thomas, Michael L; Willis, Sherry L; Marsiske, Michael; Gross, Alden L; Rebok, George W; Parisi, Jeanine M

    2015-09-01

    Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. (c) 2015 APA, all rights reserved).

  19. High Voltage Gain Dual Active Bridge Converter with an Extended Operation Range for Renewable Energy Systems

    DEFF Research Database (Denmark)

    Zhang, Zhe; Tomas Manez, Kevin; Yudi, Xiao

    2018-01-01

    Developing bidirectional dc-dc converters has become a critical research topic and gains more and more attention in recent years due to the extensive applications of smart grids with energy storages, hybrid and electrical vehicles and dc microgrids. In this paper, a Partial Parallel Dual Active...

  20. S-phenylpiracetam, a selective DAT inhibitor, reduces body weight gain without influencing locomotor activity.

    Science.gov (United States)

    Zvejniece, Liga; Svalbe, Baiba; Vavers, Edijs; Makrecka-Kuka, Marina; Makarova, Elina; Liepins, Vilnis; Kalvinsh, Ivars; Liepinsh, Edgars; Dambrova, Maija

    2017-09-01

    S-phenylpiracetam is an optical isomer of phenotropil, which is a clinically used nootropic drug that improves physical condition and cognition. Recently, it was shown that S-phenylpiracetam is a selective dopamine transporter (DAT) inhibitor that does not influence norepinephrine (NE) or serotonin (5-HT) receptors. The aim of the present study was to study the effects of S-phenylpiracetam treatment on body weight gain, blood glucose and leptin levels, and locomotor activity. Western diet (WD)-fed mice and obese Zucker rats were treated daily with peroral administration of S-phenylpiracetam for 8 and 12weeks, respectively. Weight gain and plasma metabolites reflecting glucose metabolism were measured. Locomotor activity was detected in an open-field test. S-phenylpiracetam treatment significantly decreased body weight gain and fat mass increase in the obese Zucker rats and in the WD-fed mice. In addition, S-phenylpiracetam reduced the plasma glucose and leptin concentration and lowered hyperglycemia in a glucose tolerance test in both the mice and the rats. S-phenylpiracetam did not influence locomotor activity in the obese Zucker rats or in the WD-fed mice. The results demonstrate that S-phenylpiracetam reduces body weight gain and improves adaptation to hyperglycemia without stimulating locomotor activity. Our findings suggest that selective DAT inhibitors, such as S-phenylpiracetam, could be potentially useful for treating obesity in patients with metabolic syndrome with fewer adverse health consequences compared to other anorectic agents. Copyright © 2017. Published by Elsevier Inc.

  1. The influence of loss and gain of body mass on ovarian activity in ...

    African Journals Online (AJOL)

    Ovarian activity was studied in 36 dry, Bos taurus cows fed to achieve different rates of body mass loss and gain in a 2 x 2 factorial experiment. Cows were fed hay to supply either 70% (Treatments 1, 2) or 40% (Treatments. 3,4) of their ME requirements for maintenance until they became anoestrus. Following a 90-day ...

  2. 5-Aminoimidazole-4-carboxamide ribonucleotide prevents fat gain following the cessation of voluntary physical activity.

    Science.gov (United States)

    Ruegsegger, Gregory N; Sevage, Joseph A; Childs, Thomas E; Grigsby, Kolter B; Booth, Frank W

    2017-11-01

    What is the central question of this study? We investigated whether 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) could prevent acute increases in body fat and changes in omental and subcutaneous adipose tissue following the sudden transition from physical activity to physical inactivity. What is the main finding and its importance? AICAR prevented fat gains following the transition from physical activity to inactivity to levels comparable to rats that remained physically active. AICAR and continuous physical activity produced depot-specific changes in cyclin A1 mRNA and protein that were associated with the prevention of fat gain. These findings suggest that targeting AMP-activated protein kinase signalling could oppose rapid adipose mass growth. The transition from physical activity to inactivity is associated with drastic increases in 'catch-up' fat that in turn foster the development of many obesity-associated maladies. We tested whether 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) treatment would prevent gains in body fat following the sudden transition from a physically active state to an inactive state by locking a voluntary running wheel. Male Wistar rats were either sedentary (SED) or given wheel access for 4 weeks, at which time rats with wheels continued running (RUN), had their wheel locked (WL) or had WL with daily AICAR injection (WL + AICAR) for 1 week. RUN and WL + AICAR prevented gains in body fat compared with SED and WL (P RUN and WL + AICAR compared with SED and WL groups (P run, and that together, continuous physical activity and AICAR could, at least initially in these conditions, exert similar inhibitory effects on adipogenesis in a depot-specific manner. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.

  3. Telmisartan prevents weight gain and obesity through activation of peroxisome proliferator-activated receptor-delta-dependent pathways

    DEFF Research Database (Denmark)

    He, Hongbo; Yang, Dachun; Ma, Liqun

    2010-01-01

    Telmisartan shows antihypertensive and several pleiotropic effects that interact with metabolic pathways. In the present study we tested the hypothesis that telmisartan prevents adipogenesis in vitro and weight gain in vivo through activation of peroxisome proliferator-activated receptor (PPAR)-d...

  4. The effect of winding and core support material on the thermal gain dependence of a fluxgate magnetometer sensor

    Science.gov (United States)

    Miles, David M.; Mann, Ian R.; Kale, Andy; Milling, David K.; Narod, Barry B.; Bennest, John R.; Barona, David; Unsworth, Martyn J.

    2017-10-01

    Fluxgate magnetometers are an important tool in geophysics and space physics but are typically sensitive to variations in sensor temperature. Changes in instrumental gain with temperature, thermal gain dependence, are thought to be predominantly due to changes in the geometry of the wire coils that sense the magnetic field and/or provide magnetic feedback. Scientific fluxgate magnetometers typically employ some form of temperature compensation and support and constrain wire sense coils with bobbins constructed from materials such as MACOR machinable ceramic (Corning Inc.) which are selected for their ultra-low thermal deformation rather than for robustness, cost, or ease of manufacturing. We present laboratory results comparing the performance of six geometrically and electrically matched fluxgate sensors in which the material used to support the windings and for the base of the sensor is varied. We use a novel, low-cost thermal calibration procedure based on a controlled sinusoidal magnetic source and quantitative spectral analysis to measure the thermal gain dependence of fluxgate magnetometer sensors at the ppm°C-1 level in a typical magnetically noisy university laboratory environment. We compare the thermal gain dependence of sensors built from MACOR, polyetheretherketone (PEEK) engineering plastic (virgin, 30 % glass filled and 30 % carbon filled), and acetal to examine the trade between the thermal properties of the material, the impact on the thermal gain dependence of the fluxgate, and the cost and ease of manufacture. We find that thermal gain dependence of the sensor varies as one half of the material properties of the bobbin supporting the wire sense coils rather than being directly related as has been historically thought. An experimental sensor constructed from 30 % glass-filled PEEK (21.6 ppm°C-1) had a thermal gain dependence within 5 ppm°C-1 of a traditional sensor constructed from MACOR ceramic (8.1 ppm°C-1). If a modest increase in thermal

  5. The effect of winding and core support material on the thermal gain dependence of a fluxgate magnetometer sensor

    Directory of Open Access Journals (Sweden)

    D. M. Miles

    2017-10-01

    Full Text Available Fluxgate magnetometers are an important tool in geophysics and space physics but are typically sensitive to variations in sensor temperature. Changes in instrumental gain with temperature, thermal gain dependence, are thought to be predominantly due to changes in the geometry of the wire coils that sense the magnetic field and/or provide magnetic feedback. Scientific fluxgate magnetometers typically employ some form of temperature compensation and support and constrain wire sense coils with bobbins constructed from materials such as MACOR machinable ceramic (Corning Inc. which are selected for their ultra-low thermal deformation rather than for robustness, cost, or ease of manufacturing. We present laboratory results comparing the performance of six geometrically and electrically matched fluxgate sensors in which the material used to support the windings and for the base of the sensor is varied. We use a novel, low-cost thermal calibration procedure based on a controlled sinusoidal magnetic source and quantitative spectral analysis to measure the thermal gain dependence of fluxgate magnetometer sensors at the ppm°C−1 level in a typical magnetically noisy university laboratory environment. We compare the thermal gain dependence of sensors built from MACOR, polyetheretherketone (PEEK engineering plastic (virgin, 30 % glass filled and 30 % carbon filled, and acetal to examine the trade between the thermal properties of the material, the impact on the thermal gain dependence of the fluxgate, and the cost and ease of manufacture. We find that thermal gain dependence of the sensor varies as one half of the material properties of the bobbin supporting the wire sense coils rather than being directly related as has been historically thought. An experimental sensor constructed from 30 % glass-filled PEEK (21.6 ppm°C−1 had a thermal gain dependence within 5 ppm°C−1 of a traditional sensor constructed from MACOR ceramic (8.1

  6. Interleukin-18 activates skeletal muscle AMPK and reduces weight gain and insulin resistance in mice

    DEFF Research Database (Denmark)

    Madsen, Birgitte Lindegaard; Matthews, Vance B; Brandt, Claus

    2013-01-01

    Circulating interleukin (IL)-18 is elevated in obesity, but paradoxically causes hypophagia. We hypothesized that IL-18 may attenuate high fat diet induced insulin resistance by activating AMP activated protein kinase (AMPK). We studied mice with a global deletion of the α isoform of the IL-18...... receptor (IL-18R(-/-)), fed a standard chow or high fat diet (HFD). We next performed gain of function experiments in skeletal muscle, in vitro, ex vivo and in vivo. We show that IL-18 is implicated in metabolic homeostasis, inflammation and insulin resistance via mechanisms involving the activation...

  7. Representation of potential information gain to measure the price of anarchy on ISR activities

    Science.gov (United States)

    Ortiz-Peña, Hector J.; Hirsch, Michael; Karwan, Mark; Nagi, Rakesh; Sudit, Moises

    2013-05-01

    One of the main technical challenges facing intelligence analysts today is effectively determining information gaps from huge amounts of collected data. Moreover, getting the right information to/from the right person (e.g., analyst, warfighter on the edge) at the right time in a distributed environment has been elusive to our military forces. Synchronization of Intelligence, Surveillance, and Reconnaissance (ISR) activities to maximize the efficient utilization of limited resources (both in quantity and capabilities) has become critically important to increase the accuracy and timeliness of overall information gain. Given this reality, we are interested in quantifying the degradation of solution quality (i.e., information gain) as a centralized system synchronizing ISR activities (from information gap identification to information collection and dissemination) moves to a more decentralized framework. This evaluation extends the concept of price of anarchy, a measure of the inefficiency of a system when agents maximize decisions without coordination, by considering different levels of decentralization. Our initial research representing the potential information gain in geospatial and time discretized spaces is presented. This potential information gain map can represent a consolidation of Intelligence Preparation of the Battlefield products as input to automated ISR synchronization tools. Using the coordination of unmanned vehicles (UxVs) as an example, we developed a mathematical programming model for multi-perspective optimization in which each UxV develops its own fight plan to support mission objectives based only on its perspective of the environment (i.e., potential information gain map). Information is only exchanged when UxVs are part of the same communication network.

  8. Simulation of the effects of coated material SEY property on output electron energy distribution and gain of microchannel plates

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Lin [Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Xi' an Jiaotong University, Xi' an 710049 (China); Wang, Xingchao [North Night Vision Technology (NNVT) Co., Ltd., Nanjing 210110 (China); Tian, Jinshou, E-mail: tianjs@opt.ac.cn [Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006 (China); Liu, Chunliang [Xi' an Jiaotong University, Xi' an 710049 (China); Liu, Hulin [Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Chen, Ping [Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Graduate School of Chinese Academy of Sciences (CAS), Beijing 100049 (China); Wei, Yonglin; Sai, Xiaofeng [Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); Sun, Jianning; Si, Shuguang [North Night Vision Technology (NNVT) Co., Ltd., Nanjing 210110 (China); Wang, Xing; Lu, Yu [Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi' an Institute of Optics and Precision Mechanics (XIOPM), Chinese Academy of Sciences (CAS), Xi' an 710119 (China); and others

    2016-12-21

    To obtain a high spatial resolution of a image intensifier based on microchannel plate (MCP), the long tail in the exit energy distribution of the output electrons (EDOE) is undesirable. The existing solution is increasing the penetration depth of the MCP output electrode, which will result in a serious gain reduction. Coating the MCP output electrode with efficient secondary electron yield (SEY) materials is supposed to be an effective approach to suppress the unfavorable tail component in the EDOE without negative effects on the gain. In our work, a three-dimensional MCP single channel model is developed in CST STUDIO SUITE to systematically investigate the dependences of the EDOE and the gain on the SEY property of the coated material, based on the Finite Integral Technique and Monte Carlo method. The results show that besides the high SEY of the coated material, the low incident energy corresponding to the peak SEY is another essential element affecting the electron yield in the final stage of multiplication and suppressing the output energy spread.

  9. Phase and gain control policies for robust active vibration control of flexible structures

    International Nuclear Information System (INIS)

    Zhang, K; Ichchou, M N; Scorletti, G; Mieyeville, F

    2013-01-01

    The interest of this paper is to develop a general and systematic robust control methodology for active vibration control of flexible structures. For this purpose, first phase and gain control policies are proposed to impose qualitative frequency-dependent requirements on the controller to consider a complete set of control objectives. Then the proposed control methodology is developed by employing phase and gain control policies in the dynamic output feedback H ∞  control: according to the set of control objectives, phase and gain control policies incorporate necessary weighting functions and determine them in a rational and systematic way; on the other hand, with the appropriate weighting functions efficient H ∞  control algorithms can automatically realize phase and gain control policies and generate a satisfactory H ∞  controller. The proposed control methodology can be used for both SISO and MIMO systems with collocated or non-collocated sensors and actuators. In this paper, it is validated on a non-collocated piezoelectric cantilever beam. Both numerical simulations and experimental results demonstrate the effectiveness of the proposed control methodology. (paper)

  10. Advertising Content in Physical Activity Print Materials.

    Science.gov (United States)

    Cardinal, Bradley J.

    2002-01-01

    Evaluated the advertising content contained in physical activity print materials. Analysis of print materials obtained from 80 sources (e.g., physicians' offices and fitness events) indicated that most materials contained some form of advertising. Materials coming from commercial product vendors generally contained more advertising than materials…

  11. Achievement of public health recommendations for physical activity and prevention of gains in adiposity in adults

    DEFF Research Database (Denmark)

    Grøntved, A.

    2013-01-01

    Physical activity (PA) is considered a cornerstone in weight control and public health guidelines recommend regular participation to prevent gains in adiposity. It may therefore come as a surprise that the cumulative evidence from observational studies to support this is not strong. A weakness...... of many published observational studies on this topic has been a reliance on a single baseline assessment of PA. Using only the baseline information on PA in a prospective study cause misclassification because of participants often change activity level during follow-up. In turn this causes regression...

  12. A Study on Knowledge Gain and Retention when Using Multimedia Learning Materials of Different Quality

    Directory of Open Access Journals (Sweden)

    Maja Gligora Marković

    2015-07-01

    The results of an experimental study that involves low-quality and high-quality MLMs for two different topics and their effects on knowledge gain and retention of the polytechnic school students are presented. For the purpose of the research the LORI assessment tool was used to evaluate the quality of MLMs. The analysis of research data shows that MLMs developed according to the principles of multimedia learning and principles for reducing cognitive load were perceived as being of higher quality than those that were not developed using multimedia principles. Furthermore, the students’ usage of high-quality MLMs during treatment resulted in better knowledge acquisition and retention indicated by significantly higher scores in the three knowledge assessments.

  13. Experience gained from some incidents related to the shipment of radioactive materials

    International Nuclear Information System (INIS)

    Devillers, C.

    1989-08-01

    The number of accidents occurring during shipment of dangerous materials in France varies between 200 and 250 each year. Those concerning radioactive materials represent one or two events per year. Six incidents or accidents recorded these last few years have been selected as particularly significant; they include not only events on public highways but also events on nuclear sites relevant to transportation safety. These events are summarized together with corrective actions engaged after analysis of the causes of the events. Finally, more general conclusions drawn from these abnormal events are presented from the point of view of emergency preparedness

  14. Cell-to-module optical loss/gain analysis for various photovoltaic module materials through systematic characterization

    Science.gov (United States)

    Hsian Saw, Min; Khoo, Yong Sheng; Singh, Jai Prakash; Wang, Yan

    2017-08-01

    Reducing levelized cost of electricity (LCOE) is important for solar photovoltaics to compete against other energy sources. Thus, the focus should not only be on improving the solar cell efficiency, but also on continuously reducing the losses (or achieving gain) in the cell-to-module process. This can be achieved by choosing the appropriate module material and design. This paper presents a detailed and systematic characterization of various photovoltaic (PV) module materials (encapsulants, tabbing ribbons, and backsheets) and an evaluation of their impact on the output power of silicon wafer-based PV modules. Various characterization tools/techniques, such as UV-vis (reflectance) measurement, external quantum efficiency (EQE) measurement and EQE line-scan are used. Based on the characterization results, we use module materials with the best-evaluated optical performance to build “optimized modules”. Compared to the standard mini-module, an optical gain of more than 5% is achievable for the “optimized module” with selected module materials.

  15. Light-scattering properties of a woven shade-screen material used for daylighting and solar heat-gain control

    Energy Technology Data Exchange (ETDEWEB)

    Jonsson, Jacob; Jonsson, Jacob C.; Lee, Eleanor S.; Rubin, Mike

    2008-08-01

    Shade-screens are widely used in commercial buildings as a way to limit the amount of direct sunlight that can disturb people in the building. The shade screens also reduce the solar heat-gain through glazing the system. Modern energy and daylighting analysis software such as EnergyPlus and Radiance require complete scattering properties of the scattering materials in the system. In this paper a shade screen used in the LBNL daylighting testbed is characterized using a photogoniometer and a normal angle of incidence integrating sphere. The data is used to create a complete bi-directional scattering distribution function (BSDF) that can be used in simulation programs. The resulting BSDF is compared to a model BADFs, both directly and by calculating the solar heat-gain coefficient for a dual pane system using Window 6.

  16. Qualitative Assessment of Key Messages about Nutrition and Weight Gain in Pregnancy in Printed Educational Materials in Alberta.

    Science.gov (United States)

    Forbes, Laura; Baarda, Janis; Mayan, Maria; Bell, Rhonda C

    2017-12-01

    Printed educational materials are a common source of health information, although their effectiveness in improving women's knowledge or self-care in pregnancy has been questioned. This study describes the information in printed educational materials that address healthy eating during pregnancy and gestational weight gain (GWG) that are currently used in Alberta, Canada. Content of 6 resources was analyzed using a constant comparison qualitative approach. Resources emphasized healthy eating, prenatal supplements, folate supplementation, and healthy weight gain. More resources discussed the importance of "eating enough" than provided guidance on avoiding excessive GWG. Themes identified were: "everything is important" meaning that all healthy behaviours are important, making prioritization difficult; "more is more" emphasized eating more over moderation; "everyone is individual" suggests women seek individualized care through the care provider; and "contradictions" describes differences in content and recommendations within and between resources. New or revised versions of resources should provide congruent information with up-to-date recommendations that are easily prioritized. Care providers should be aware of contradictory information or information that does not align with current recommendations within printed educational materials and be ready to help women address the areas important for her personal behaviour change.

  17. Instrumentation amplifier implements second-order active low-pass filter with high gain factor

    International Nuclear Information System (INIS)

    Blomqvist, Kim H; Eskelinen, Pekka; Sepponen, Raimo E

    2011-01-01

    A single-ended second-order active low-pass filter can simultaneously provide high gain factor and dc voltage subtraction. This makes it possible to reduce the number of components and signal processing stages needed in an application where small voltage changes are measured on the top of large dc voltage masked by a large amplitude oscillating carrier. The filter described in this paper is constructed from a conventional 3-op-amp instrumentation amplifier and five passive circuit elements. (technical design note)

  18. Weight gain in healthy pregnant women in relation to pre-pregnancy BMI, diet and physical activity.

    Science.gov (United States)

    Merkx, Astrid; Ausems, Marlein; Budé, Luc; de Vries, Raymond; Nieuwenhuijze, Marianne J

    2015-07-01

    to explore gestational weight gain in healthy women in relation to pre-pregnancy Body Mass Index, diet and physical activity. a cross-sectional survey was conducted among 455 healthy pregnant women of all gestational ages receiving antenatal care from an independent midwife in the Netherlands. Weight gain was assessed using the Institute of Medicine (IOM) guidelines and classified as below, within, or above the guidelines. A multinomial regression analysis was performed with weight gain classifications as the dependent variable (within IOM-guidelines as reference). Independent variables were pre-pregnancy Body Mass Index, diet (broken down into consumption of vegetables, fruit and fish) and physical activity (motivation to engage in physical activity, pre-pregnancy physical activity and decline in physical activity during pregnancy). Covariates were age, gestational age, parity, ethnicity, family income, education, perceived sleep deprivation, satisfaction with pre-pregnancy weight, estimated prepregnancy body mass index, smoking, having a weight gain goal and having received weight gain advice from the midwife. forty-two per cent of the women surveyed gained weight within the guidelines. Fourteen per cent of the women gained weight below the guidelines and 44 per cent gained weight above the guidelines. Weight gain within the guidelines, compared to both above and below the guidelines, was not associated with pre-pregnancy Body Mass Index nor with diet. A decline in physical activity was associated with weight gain above the guidelines (OR 0.54, 95 per cent CI 0.33-0.89). Weight gain below the guidelines was seen more often in women who perceived a greater sleep deprivation (OR 1.20, 95 per cent CI 1.02-1.41). Weight gain above the guidelines was seen less often in Caucasian women in comparison to non-Caucasian women (OR 0.22, 95 per cent CI 0.08-0.56) and with women who did not stop smoking during pregnancy (OR 0.49, 95 per cent CI 0.25-0.95). a decline in

  19. Effect of Phase Change Materials (PCMs Integrated into a Concrete Block on Heat Gain Prevention in a Hot Climate

    Directory of Open Access Journals (Sweden)

    Ahmad Hasan

    2016-10-01

    Full Text Available In the current study, a phase change material (PCM contained in an insulated concrete block is tested in extremely hot weather in the United Arab Emirates (UAE to evaluate its cooling performance. An insulated chamber is constructed behind the block containing PCM to mimic a scaled down indoor space. The effect of placement of the PCM layer on heat gain indoors is studied at two locations: adjacent to the outer as well as the inner concrete layer. The inclusion of PCM reduced heat gain through concrete blocks compared to blocks without PCM, yielding a drop in cooling load indoors. The placement of PCM and insulation layers adjacent to indoors exhibited better cooling performance compared to that adjacent to the outdoors. In the best case, a temperature drop of 8.5% and a time lag of 2.6 h are achieved in peak indoor temperature, rendering a reduction of 44% in the heat gain. In the tested hot climate, the higher ambient temperature and the lower wind speed hampered heat dissipation and PCM re-solidification by natural ventilation. The findings recommend employing a mechanical ventilation in hot climates to enhance regeneration of the PCM to solid state for its optimal performance.

  20. Effects of physical activity during pregnancy and gestational weight gain on newborn weight and length at birth in Warmińsko-Mazurskie province

    OpenAIRE

    Katarzyna Przybyłowicz; Mariusz Przybyłowicz; Marek Grzybiak; Katarzyna Janiszewska

    2014-01-01

    Background. Epidemiological research has identifi ed a relationship between maternal physical activity, early nutrition and infant birth weight with likelihood of developing future diseases. The aim of the study was to determine a relationship between gestational weight gain and physical activity during pregnancy to the nutritional status of newborns. Material and methods. The presented study was conducted in the period from February 2010 until November 2012 in the gynecological and obste...

  1. Antenatal weight management: Diet, physical activity, and gestational weight gain in early pregnancy.

    Science.gov (United States)

    Swift, Judy A; Langley-Evans, Simon C; Pearce, Jo; Jethwa, Preeti H; Taylor, Moira A; Avery, Amanda; Ellis, Sarah; McMullen, Sarah; Elliott-Sale, Kirsty J

    2017-06-01

    to investigate women's physical activity levels, diet and gestational weight gain, and their experiences and motivations of behavior change. analysis of cross-sectional data collected during a longitudinal, cohort study examining physiological, psychological, sociodemographic, and self-reported behavioural measures relating to bodyweight. women recruited from routine antenatal clinics at the Nottingham University Hospitals NHS Trust. 193 women ≤27 weeks gestation and aged 18 years or over. MEASUREMENTS & FINDINGS: measurements included weight and height, the Dietary Instrument for Nutrition Education (Brief Version), the International Physical Activity Questionnaire (Short Form), and open questions of perceptions of behaviour change. 50.3% (n=97) were overweight/obese, and women gained 0.26kg/wk (IQR 0.34kg/wk) since conception. The majority consumed low levels of fat (n=121; 63.4%), high levels of unsaturated fat (n=103; 53.9%), and used a dietary supplement (n=166; 86.5%). However, 41% (n=76) were inactive, 74.8% (n=143) did not consume high levels of fibre, and 90.0% (n=171) consumed less than 5 portions of fruit and vegetables a day. Body mass index category was not associated with diet, physical activity levels, or gestational weight gain. Themes generated from open-questions relating to behaviour change were: (1) Risk management, (2) Coping with symptoms, (3) Self-control, (4) Deviation from norm, (5) Nature knows best. early pregnancy is a period of significant and heterogeneous behaviour change, influenced by perceptions of risk and women's lived experience. Behaviour was influenced not only by perceptions of immediate risk to the fetus, but also by the women's lived experience of being pregnant. There are exciting opportunities to constructively reframe health promotion advice relating to physical activity and diet in light of women's priorities. The need for individualized advice is highlighted, and women across all body mass index categories would

  2. Enhancing Diversity in Undergraduate Science: Self-Efficacy Drives Performance Gains with Active Learning.

    Science.gov (United States)

    Ballen, Cissy J; Wieman, Carl; Salehi, Shima; Searle, Jeremy B; Zamudio, Kelly R

    2017-01-01

    Efforts to retain underrepresented minority (URM) students in science, technology, engineering, and mathematics (STEM) have shown only limited success in higher education, due in part to a persistent achievement gap between students from historically underrepresented and well-represented backgrounds. To test the hypothesis that active learning disproportionately benefits URM students, we quantified the effects of traditional versus active learning on student academic performance, science self-efficacy, and sense of social belonging in a large (more than 250 students) introductory STEM course. A transition to active learning closed the gap in learning gains between non-URM and URM students and led to an increase in science self-efficacy for all students. Sense of social belonging also increased significantly with active learning, but only for non-URM students. Through structural equation modeling, we demonstrate that, for URM students, the increase in self-efficacy mediated the positive effect of active-learning pedagogy on two metrics of student performance. Our results add to a growing body of research that supports varied and inclusive teaching as one pathway to a diversified STEM workforce. © 2017 C. J. Ballen et al. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  3. Activation analysis of high pure quartz used as packing materials

    International Nuclear Information System (INIS)

    Luknitskij, V.A.; Morozov, B.A.

    1979-01-01

    A γ-spectrometric technique of neutron activation determination of microelements in quartz tubes used as a packing material for irradiation in reactors is reported. The analysis of 29 micro-admixtures in quartz tubes of USSR brands ''spectrtosil'' and ''KV'' was carried out. The γ-spectra of ''KV'' quartz irradiated by thermal and epithermal neutrons are presented. The activation by epithermal neutrons provides an activity gain for the nuclei whose resonance integral is high enough as compared to the activation cross-section with regard to thermal neutrons. The activation by epithermal neutrons permits additional determination of W, Cd, V, Th, Mn and Ni and provides for a substantial decrease in the activity of 24 Na, 42 K, 140 La, 46 Sc, 141 Ce, 51 Cr, and 59 Fe, which hinder the determination of the above-mentioned elements. The microelement composition of Soviet-made quartz varieties is compared to that of foreign-made quartz brands

  4. African American and White women׳s perceptions of weight gain, physical activity, and nutrition during pregnancy.

    Science.gov (United States)

    Whitaker, Kara M; Wilcox, Sara; Liu, Jihong; Blair, Steven N; Pate, Russell R

    2016-03-01

    To describe African American and White women's perceptions of weight gain, physical activity, and nutrition during pregnancy and to explore differences in perceptions by race. Qualitative interview study. Two Ob/Gyn clinics in South Carolina, USA. Thirty pregnant women (15 African American, 15 White) between 20 and 30 weeks gestation, equally represented across pre-pregnancy BMI categories (10 normal weight, 10 overweight, and 10 obese). White women more frequently described intentions to meet weight gain, physical activity, and dietary guidelines in pregnancy than African American women. African American women were more concerned with inadequate weight gain while White women more commonly expressed concerns about excessive weight gain. More White women discussed the importance of physical activity for weight management. Regardless of race, few women described risks of excessive weight gain or benefits of physical activity as it relates to the baby's health. The primary cited barrier of healthy eating was the high cost of fresh produce. Several knowledge gaps as well as race differences were identified in women's perceptions and intentions toward weight gain, physical activity, and nutrition during pregnancy. Future interventions should seek to educate women about common misperceptions. It may be necessary to culturally tailor gestational weight gain interventions to optimise health outcomes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. 78 FR 74125 - Agency Information Collection Activities; Comment Request; Measuring Educational Gain in the...

    Science.gov (United States)

    2013-12-10

    ...; Comment Request; Measuring Educational Gain in the National Reporting System for Adult Education AGENCY... Educational Gain in the National Reporting System for Adult Education. OMB Control Number: 1830-0567. Type of... tests to measure and report educational gain under the NRS. Dated: December 4, 2013. Tomakie Washington...

  6. Influence of pre-pregnancy leisure time physical activity on gestational and postpartum weight gain and birth weight

    DEFF Research Database (Denmark)

    Hegaard, Hanne Kristine; Rode, Line; Katballe, Malene Kjær

    2017-01-01

    In order to examine the association between pre-pregnancy leisure time physical activities and gestational weight gain, postpartum weight gain and birth weight, we analysed prospectively collected data from 1827 women with singleton term pregnancies. Women were categorised in groups of sedentary...... risk of having a gestational weight gain above Institute of Medicine (IOM) recommendations with an odds ratio of 2.60 (1.32-5.15) compared to light exercisers. However, birth weight and one year postpartum weight was similar for all four groups. Thus, although competitive athletes gain more weight than...... recommended during pregnancy, this may not affect birth weight or postpartum weight. Impact statement: What is already known on this subject: Previous studies have found that increased pre-pregnancy physical activity is associated with lower gestational weight gain during the last trimester, but showed...

  7. Prefrontal activation may predict working-memory training gain in normal aging and mild cognitive impairment.

    Science.gov (United States)

    Vermeij, Anouk; Kessels, Roy P C; Heskamp, Linda; Simons, Esther M F; Dautzenberg, Paul L J; Claassen, Jurgen A H R

    2017-02-01

    Cognitive training has been shown to result in improved behavioral performance in normal aging and mild cognitive impairment (MCI), yet little is known about the neural correlates of cognitive plasticity, or about individual differences in responsiveness to cognitive training. In this study, 21 healthy older adults and 14 patients with MCI received five weeks of adaptive computerized working-memory (WM) training. Before and after training, functional Near-Infrared Spectroscopy (fNIRS) was used to assess the hemodynamic response in left and right prefrontal cortex during performance of a verbal n-back task with varying levels of WM load. After training, healthy older adults demonstrated decreased prefrontal activation at high WM load, which may indicate increased processing efficiency. Although MCI patients showed improved behavioral performance at low WM load after training, no evidence was found for training-related changes in prefrontal activation. Whole-group analyses showed that a relatively strong hemodynamic response at low WM load was related to worse behavioral performance, while a relatively strong hemodynamic response at high WM load was related to higher training gain. Therefore, a 'youth-like' prefrontal activation pattern at older age may be associated with better behavioral outcome and cognitive plasticity.

  8. Association of Proton Pump Inhibitor (PPI Use with Energy Intake, Physical Activity, and Weight Gain

    Directory of Open Access Journals (Sweden)

    Jennifer L. Czwornog

    2015-10-01

    Full Text Available Studies suggest proton pump inhibitor (PPI use impacts body weight regulation, though the effect of PPIs on energy intake, energy extraction, and energy expenditure is unknown. We used data on 3073 eligible adults from the National Health and Nutrition Examination Survey (NHANES. Medication use, energy intake, diet composition, and physical activity were extracted from NHANES. Multivariate regression models included confounding variables. Daily energy intake was similar between PPI users and non-users (p = 0.41. Diet composition was similar between the two groups, except that PPI users consumed a slightly greater proportion of calories from fat (34.5% vs. 33.2%; p = 0.02. PPI users rated themselves as being as physically active as their age/gender-matched peers and reported similar frequencies of walking or biking. However, PPI users were less likely to have participated in muscle-strengthening activities (OR: 0.53; 95% CI: 0.30–0.95. PPI users reported similar sedentary behaviors to non-users. Male PPI users had an increase in weight (of 1.52 ± 0.59 kg; p = 0.021 over the previous year compared to non-users, while female PPI users had a non-significant increase in weight. The potential mechanisms for PPI-associated weight gain are unclear as we did not find evidence for significant differences in energy intake or markers of energy expenditure.

  9. Activity measurements of radon from construction materials

    Energy Technology Data Exchange (ETDEWEB)

    Fior, L.; Nicolosi Correa, J. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Paschuk, S.A., E-mail: spaschuk@gmail.com [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Denyak, V.V. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Schelin, H.R. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil); Pele Pequeno Principe Research Institute, Av. Silva Jardim, 1632, Curitiba, PR 80250-200 (Brazil); Soreanu Pecequilo, B.R. [Institute of Nuclear and Energetic Researches, IPEN, Av. Prof. Lineu Prestes, 2242-/05508-000 Sao Paulo (Brazil); Kappke, J. [Federal University of Technology - Parana, UTFPR, Av. Sete de Setembro, 3165, Curitiba, PR 80230-901 (Brazil)

    2012-07-15

    This work presents the results of radon concentration measurements of construction materials used in the Brazilian industry, such as clay (red) bricks and concrete blocks. The measurements focused on the detection of indoor radon activity during different construction stages and the analysis of radionuclides present in the construction materials. For this purpose, sealed chambers with internal dimensions of approximately 60 Multiplication-Sign 60 Multiplication-Sign 60 cm{sup 3} were built within a protected and isolated laboratory environment, and stable air humidity and temperature levels were maintained. These chambers were also used for radon emanation reduction tests. The chambers were built in four major stages: (1) assembly of the walls using clay (red) bricks, concrete blocks, and mortar; (2) installation of plaster; (3) finishing of wall surface using lime; and (4) insulation of wall surface and finishing using paint. Radon measurements were performed using polycarbonate etched track detectors. By comparing the three layers applied to the masonry walls, it was concluded that only the last step (wall painting using acrylic varnish) reduced the radon emanation, by a factor of approximately 2. Samples of the construction materials (clay bricks and concrete blocks) were ground, homogenized, and subjected to gamma-ray spectrometry analysis to evaluate the activity concentrations of {sup 226}Ra, {sup 232}Th and {sup 40}K. The values for the index of the activity concentration (I), radium equivalent activity (Ra{sub eq}), and external hazard index (H{sub ext}) showed that these construction materials could be used without restrictions or concern about the equivalent dose limit (1 mSv/year). - Highlights: Black-Right-Pointing-Pointer Radon activity in air related to building materials was measured. Black-Right-Pointing-Pointer The index of activity concentration of building materials was evaluated. Black-Right-Pointing-Pointer The radium equivalent activity of

  10. GAINS IN PERFORMANCE OF DIFFERENT METHODS OF COLLECTING ENTOMOLOGICAL MATERIALS IN ENVIRONMENTAL AND FAUNAL STUDIES ON COLEOPTERA

    Directory of Open Access Journals (Sweden)

    B. N. Saypulaeva

    2015-01-01

    Full Text Available The aim is to study the effectiveness of methods of collecting entomological materials for further ecological and faunal studies as well as to gain the main evidence in ecological and faunal studies carried out in the field. Collection of the evidence in the field is necessary for the identification of species composition and to study such aspects as the distribution of species, confinement of species to certain habitats, relations with the food objects (trophism, climate, soil and orographic environmental factors.Methodology. We have used the traditional methods of collection (hand picking, pitfall traps, pitfall traps with increased light, light traps, processing and determination of materials. In recent years, the method of collection of soil invertebrates has introduced an innovation. In expeditionary studies in the island of Tyuleny new ways have been tested of using pitfall traps equipped with an incandescent light source. They provide a higher collection efficiency of Entomological materials. List of species composition of the discussed fauna has been composed by modern taxonomy with the use of directories.Results. We have made a comparative analysis of the effectiveness of different methods of collecting entomological materials on Coleoptera (Carabidae, Scarabaeidae, Elateridae, Tenebrionidae for environmental and faunal studies in the area of Irganayskaya arid basin of intramontane Dagestan. Not all species, registered in the studied habitat, have been identified by methods of soil sampling and pitfall traps. The greatest number of species has been identified by manual collection, and the least by soil sampling. The paper shows the effectiveness of different methods of collecting entomofauna against individual families and species of the groups studied.

  11. Variation in behavioral engagement during an active learning activity leads to differential knowledge gains in college students.

    Science.gov (United States)

    LaDage, Lara D; Tornello, Samantha L; Vallejera, Jennilyn M; Baker, Emily E; Yan, Yue; Chowdhury, Anik

    2018-03-01

    There are many pedagogical techniques used by educators in higher education; however, some techniques and activities have been shown to be more beneficial to student learning than others. Research has demonstrated that active learning and learning in which students cognitively engage with the material in a multitude of ways result in better understanding and retention. The aim of the present study was to determine which of three pedagogical techniques led to improvement in learning and retention in undergraduate college students. Subjects partook in one of three different types of pedagogical engagement: hands-on learning with a model, observing someone else manipulate the model, and traditional lecture-based presentation. Students were then asked to take an online quiz that tested their knowledge of the new material, both immediately after learning the material and 2 wk later. Students who engaged in direct manipulation of the model scored higher on the assessment immediately after learning the material compared with the other two groups. However, there were no differences among the three groups when assessed after a 2-wk retention interval. Thus active learning techniques that involve direct interaction with the material can lead to learning benefits; however, how these techniques benefit long-term retention of the information is equivocal.

  12. Gestational weight gain by reduced brain melanocortin activity affects offspring energy balance in rats

    NARCIS (Netherlands)

    Heinsbroek, A. C. M.; van Dijk, G.

    Introduction: Excessive gestational body weight gain of mothers may predispose offspring towards obesity and metabolic derangements. It is difficult to discern the effects of maternal obesogenic factors-such as diet and/or thrifty genetic predisposition-from gestational weight gain per se. Methods:

  13. A postcolonial feminist discourse analysis of urban Aboriginal women's description of pregnancy-related weight gain and physical activity.

    Science.gov (United States)

    Darroch, Francine E; Giles, Audrey R

    2016-02-01

    Excessive weight gain and physical inactivity in pregnancy have been identified as risk factors for negative health outcomes for mothers and fetuses, particularly among Aboriginal women. In this paper we engage with postcolonial feminist theory and critical discourse analysis to examine the question, "how do urban Aboriginal women understand pregnancy-related weight gain and physical activity." We conducted focus groups and semi-structured interviews with 25 urban Aboriginal pregnant or postpartum women between the ages of 16 and 39 in Ottawa, Canada. Three prominent discourses emerged: Aboriginal women have different pregnancies than non-Aboriginal women because Aboriginal women gain more weight and are more likely to develop gestational diabetes; Aboriginal women feel personally responsible for and shameful about excessive weight gain; finally, Aboriginal women need culturally safe pregnancy resources. Our results illuminate the complex and often paradoxical ways in which discourses around weight gain and physical activity are produced and taken-up by Aboriginal women and their healthcare providers. Based on these findings, we argue there is a lack of accessible and culturally safe resources for urban Aboriginal women, specifically concerning weight gain and physical activity in pregnancy. We recommend the development of resources that are created for/by/with Aboriginal women to better address that issues that urban Aboriginal women themselves identify as being of key importance. Copyright © 2015 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

  14. Lower activation materials and magnetic fusion reactors

    International Nuclear Information System (INIS)

    Conn, R.W.; Bloom, E.E.; Davis, J.W.; Gold, R.E.; Little, R.; Schultz, K.R.; Smith, D.L.; Wiffen, F.W.

    1984-01-01

    Radioactivity in fusion reactors can be effectively controlled by materials selection. The detailed relationship between the use of a material for construction of a magnetic fusion reactor and the material's characteristics important to waste disposal, safety, and system maintainability has been studied. The quantitative levels of radioactivation are presented for many materials and alloys, including the role of impurities, and for various design alternatives. A major outcome has been the development of quantitative definitions to characterize materials based on their radioactivation properties. Another key result is a four-level classification scheme to categorize fusion reactors based on quantitative criteria for waste management, system maintenance, and safety. A recommended minimum goal for fusion reactor development is a reference reactor that (a) meets the requirements for Class C shallow land burial of waste materials, (b) permits limited hands-on maintenance outside the magnet's shield within 2 days of a shutdown, and (c) meets all requirements for engineered safety. The achievement of a fusion reactor with at least the characteristics of the reference reactor is a realistic goal. Therefore, in making design choices or in developing particular materials or alloys for fusion reactor applications, consideration must be given to both the activation characteristics of a material and its engineering practicality for a given application

  15. Gaining Proficiency through Task-Based Activities in the Portuguese Classroom (Beginning and Intermediate Year Case Studies)

    Science.gov (United States)

    Jones-Kellogg, Rebecca

    2015-01-01

    This paper describes a task-based activity used at the United States Military Academy, in their first- through third-semester Portuguese language sequence "Proficiencies" (Proficiências). The stand-alone task-based activity can be an effective tool in gaining foreign-language proficiency at even the lowest levels of classroom instruction…

  16. Photon activation analysis on building materials

    International Nuclear Information System (INIS)

    Schulze, D.; Heller, W.; Kupsch, H.

    1988-01-01

    With regard to the planned construction of a new microtron, first investigations on raw materials for the aerated concrete production have been done to clear up the possibilities of photon activation analysis (PAA). Irradiations have been partly carried out on linear accelerators with a self-developed moveable activation equipment. PAA results of qualitative and quantitative elemental analysis are described. The detection of chlorine is important for studying the oversalting processes in buildings. (author)

  17. NBS activities in biological reference materials

    Energy Technology Data Exchange (ETDEWEB)

    Rasberry, S.D.

    1988-12-01

    NBS activities in biological reference materials during 1986-1988 are described with a preview of plans for future certifications of reference materials. During the period, work has been completed or partially completed on about 40 reference materials of importance to health, nutrition, and environmental quality. Some of the reference materials that have been completed during the period and are described include: creatinine (SRM 914a), bovine serum albumin (SRM 927a), cholesterol in human serum (SRM's 1951-1952), aspartate aminotransferase (RM 8430), cholesterol and fat-soluble vitamins in coconut oil (SRM 1563), wheat flour (SRM 1567a), rice flour (SRM 1568a), mixed diet (RM 8431a), dinitropyrene isomers and 1-nitropyrene (SRM 1596), and complex PAH's from coal tar (SRM 1597). Oyster tissue (SRM 1566a) is being analyzed and should be available in 1988.

  18. Does objectively measured physical activity modify the association between early weight gain and fat mass in young adulthood?

    Science.gov (United States)

    Kolle, Elin; Horta, Bernardo L; Wells, Jonathan; Brage, Soren; Barros, Fernando C; Ekelund, Ulf; Hallal, Pedro C

    2017-11-25

    Substantial evidence suggests that weight gain in early life is associated with increased adiposity and other metabolic disorders later in life. It is, however, unknown whether physical activity (PA) may modify these associations. We aimed to examine whether objectively measured PA at 30 years modified the associations between conditional weight gain in infancy (0-2 y) and childhood (2-4 y) with fat mass index (FMI) and visceral abdominal fat measured at age 30 years. Prospective birth cohort study in Pelotas, Brazil, including 1874 participants with weight data at birth, two and four years of age, and measures of FMI, visceral abdominal fat and PA at a mean age of 30.2 years. At age 30, time spent (min/day) in moderate-to-vigorous physical activity (MVPA) was measured objectively using a wrist-worn accelerometer worn for four to seven consecutive days.. Multiple linear regression analyses was performed to assess the associations between conditional weight gain and outcome variables at 30 years, adjusting for covariates. We examined whether PA modified the association between conditional weight gain and the outcomes of interest by introducing an interaction term (conditional weight gain × PA) in the models. Conditional weight gain in infancy and childhood were both positively associated with later FMI (infancy weight gain: β = 0.68, 95% CI: 0.48, 0.88; P gain: β = 0.91, 95% CI: 0.70, 1.11; P gain and later FMI (β = -0.006, 95% CI: -0.011, -0.001; P = 0.029), suggesting stronger associations between weight gain and FMI in those with lower levels of MVPA. Conditional weight gain in childhood was also positively associated with visceral abdominal fat (β = 0.24, 95% CI: 0.15, 0424, P gain between 2 and 4 years of age is associated with increased FMI at age 30 years. However, higher levels of MVPA appear to attenuate this detrimental association.

  19. Active materials by four-dimension printing

    Science.gov (United States)

    Ge, Qi; Qi, H. Jerry; Dunn, Martin L.

    2013-09-01

    We advance a paradigm of printed active composite materials realized by directly printing glassy shape memory polymer fibers in an elastomeric matrix. We imbue the active composites with intelligence via a programmed lamina and laminate architecture and a subsequent thermomechanical training process. The initial configuration is created by three-dimension (3D) printing, and then the programmed action of the shape memory fibers creates time dependence of the configuration—the four-dimension (4D) aspect. We design and print laminates in thin plate form that can be thermomechanically programmed to assume complex three-dimensional configurations including bent, coiled, and twisted strips, folded shapes, and complex contoured shapes with nonuniform, spatially varying curvature. The original flat plate shape can be recovered by heating the material again. We also show how the printed active composites can be directly integrated with other printed functionalities to create devices; here we demonstrate this by creating a structure that can assemble itself.

  20. Neutron activation analysis of biological material

    International Nuclear Information System (INIS)

    Kucera, J.; Simkova, M.; Obrusnik, I.

    1985-01-01

    The possibilities are briefly summed up of usino. NAA (neutron activation analysis) for determining element traces in foodstuffs and their intake by organisms, for monitoring changes in the content of important trace elements in tissues and body fluids owing to environmental pollution, for verifying the results of other analytical techniques and for certifying the content of element traces in reference materials. Examples are given of the use of NAA, and the results are summed up of the determination of Cd, Mn and Zn in biological reference materials NBS SRM-1577, Bovine Liver, Bowen's Kale, IAEA Milk Powder A-11 and IAEA Animal Muscle H-4. (E.S.)

  1. Neutron activation analysis of geological material

    International Nuclear Information System (INIS)

    Greef, G.J.

    1977-05-01

    In neutron activation analysis the precision and accuracy of results are often misleading, since only the statistical errors which accompany the measuring of radioactivity are taken into consideration. Several other factors can, however, also influence precision and accuracy. It was found that a geological sample was contaminated with the construction material of the mill in which it had been pulverised. Several geometrical differences which could possibly play a role were also investigated. Impurities in the irradiation containers affect the determination of some elements in the samples; the contamination materials in quarts irradiation tubes were determined. The flux gradients which may effect the relative activities of the samples and standards were measured. Suitable standards are necessary to ensure accurate analyses of geological material. Available natural standards were critically evaluated and several methods were investigated by which synthetic standards may be prepared. In order to accurately determine gallium, lanthanum and samarium by means of neutron activation analysis, sodium first had to be removed. After irradiation the sample was dissolved in a mixture of acids and the soidium absorbed from the solution on a hydrated antimony pentoxide column. Gallium, lanthanum and samarium activities were measured by means of precision gamma-spectrometry

  2. Supercapacitive characteristics of electrochemically active porous materials

    Directory of Open Access Journals (Sweden)

    VLADIMIR V. PANIC

    2008-06-01

    Full Text Available The results of an investigation of the capacitive characteristics of sol–gel-processed titanium- and carbon-supported electrochemically active noble metal oxides, as representatives of porous electrode materials, are presented in the lecture. The capacitive properties of these materials were correlated to their composition, the preparation conditions of the oxides and coatings, the properties of the carbon support and to the composition of the electrolyte. The results of the electrochemical test methods, cyclic voltammetry and electrochemical impedance spectroscopy, were employed to resolve the possible physical structures of the mentioned porous materials, which are governed by the controlled conditions of the preparation of the oxide by the sol–gel process.

  3. The Effects of Gain- versus Loss-Framed Messages Following Health Risk Information on Physical Activity in Individuals With Multiple Sclerosis.

    Science.gov (United States)

    Lithopoulos, Alexander; Bassett-Gunter, Rebecca L; Martin Ginis, Kathleen A; Latimer-Cheung, Amy E

    2017-06-01

    Few people with multiple sclerosis engage in physical activity. Messaging interventions may motivate more physical activity among these individuals. The purpose of this online study was to evaluate an intervention presenting participants with multiple sclerosis (N = 237) with risk information (i.e., information demonstrating people with multiple sclerosis are more likely to experience certain health issues) or no risk information followed by gain- or loss-framed physical activity messages. Participants completed questionnaires on Days 1, 6, and 28 and received information material on Days 2-5. The dependent variables were as follows: physical activity intentions and behavior, response and task efficacy, perceived threat (i.e., perception of threat to health issues relevant to people with multiple sclerosis), and avoidance (i.e., avoiding thinking about/doing something about the health issues presented in the messages). Analyses indicated physical activity and response efficacy increased over time. Also, participants receiving risk information had higher levels of physical activity and perceived threat. However, manipulation checks showed no differences between participants regarding perceptions of risk information or gain/loss-framed messages. Despite the lack of impact of the framing intervention, this study suggests that a brief informational intervention can positively influence physical activity and certain correlates of physical activity among people with multiple sclerosis.

  4. Neutron activation analysis of some building materials

    International Nuclear Information System (INIS)

    Salagean, M.; Pantelica, A.; Georgescu, I.I.; Muntean, M.I.

    1999-01-01

    Over the past decade, indoor air quality has become a growing environmental problem. A careful selection of building materials concerning the acceptance of chemical and radioactive emissions is one of the ways to ensure high indoor air quality. Nowadays, it is a tendency to obtain new building materials having good isolation properties and low density by using the cheap and practically inexhaustible solid waste products like furnace slag, fly coal ash and phosphogypsum, without combustion. The Romanian furnace slag containing generally, above 45 % CaO can be used alone or mixed with fly ash to obtain some binder materials with mechanical resistance comparable to the Portland cement. Different additives such as CaO+Na 2 SO 4 or CaCl 2 +Na 2 SO 4 are used as activating admixtures. Concentrations of As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Mo, Na, Nd, Rb, Sb, Sc, Sr, Ta, Tb, Th, U, Yb, W and Zn in seven Romanian building materials were determined by Instrumental Neutron Activation Analysis (INAA) method at WWR-S Reactor of IFIN-HH, Bucharest. Raw material used in the cement production (∼75 % limestone, ∼25 % clay), cement samples from three different factories, furnace slag, phosphogypsum, and a type of brick compacted from furnace slag, fly coal ash, phosphogypsum, lime and cement have been analyzed. The fly coal ashes from five Romanian coal-fired power plants, resulting by the combustion of the xyloide brown coals, lignite and bituminous-subbituminous coals were previously analyzed. It was found that the content of the toxic microelements like As, Co, Cr, Th, U, Zn in the ceramic blocks is especially due to the slag and fly ash, the main components. This content depends on the particular sources of mineral raw materials. The presence of U, Th and K in slag is mainly correlated with the limestone and dolomite as used in the metallurgical process. (authors)

  5. From Atmospheric Awareness to Active Materiality

    DEFF Research Database (Denmark)

    Wieczorek, Izabela

    2013-01-01

    ‘Atmosphere’ has recently claimed more attention in architectural discourse and practice leading to the revaluation of embodiment as a basis for the interaction with an environment. In this context, architectural space is understood as a space of engagement that ‘appears’ to us as a result....... In this multifaceted relationship materials are: carriers of effects and phenomena, encoders of our reminiscences and memories, detonators of physical, physiological and emotional contingencies, activators of the aesthetic occurrence. This reading defines materiality as an active and operative force – as a means...... parameters as a data upon which projects develop. Thus, the aim is to illustrate this particular projective genealogy, one that builds upon ‘atmospheric awareness’ where seeking an effect and affect is implicit and foregrounding perceptual and emotional engagement is conscious – i.e. one that defines so...

  6. Additive Manufacturing of Catalytically Active Living Materials.

    Science.gov (United States)

    Saha, Abhijit; Johnston, Trevor G; Shafranek, Ryan T; Goodman, Cassandra J; Zalatan, Jesse G; Storti, Duane W; Ganter, Mark A; Nelson, Alshakim

    2018-04-25

    Living materials, which are composites of living cells residing in a polymeric matrix, are designed to utilize the innate functionalities of the cells to address a broad range of applications such as fermentation and biosensing. Herein, we demonstrate the additive manufacturing of catalytically active living materials (AMCALM) for continuous fermentation. A multi-stimuli-responsive yeast-laden hydrogel ink, based on F127-dimethacrylate, was developed and printed using a direct-write 3D printer. The reversible stimuli-responsive behaviors of the polymer hydrogel inks to temperature and pressure are critical, as they enabled the facile incorporation of yeast cells and subsequent fabrication of 3D lattice constructs. Subsequent photo-cross-linking of the printed polymer hydrogel afforded a robust elastic material. These yeast-laden living materials were metabolically active in the fermentation of glucose into ethanol for 2 weeks in a continuous batch process without significant reduction in efficiency (∼90% yield of ethanol). This cell immobilization platform may potentially be applicable toward other genetically modified yeast strains to produce other high-value chemicals in a continuous biofermentation process.

  7. Reactor neutron activation analysis of industrial materials

    International Nuclear Information System (INIS)

    Niese, S.

    1983-01-01

    The specific application of neutron activation analysis (n.a.a.) for industrial materials is demonstrated by the determination of impurities in BeO, Al, Si, Cu, Ge, GaP, GaAs, steel, and irradiated uranium. A group scheme gives an orientation about the possibilities of n.a.a. The use of different standards, methods for the measurement of low radioactivities and errors caused by recoil reaction and radiation stimulated diffusion are discussed. (author)

  8. Activity measurements of radon from construction materials.

    Science.gov (United States)

    Fior, L; Nicolosi Corrêa, J; Paschuk, S A; Denyak, V V; Schelin, H R; Soreanu Pecequilo, B R; Kappke, J

    2012-07-01

    This work presents the results of radon concentration measurements of construction materials used in the Brazilian industry, such as clay (red) bricks and concrete blocks. The measurements focused on the detection of indoor radon activity during different construction stages and the analysis of radionuclides present in the construction materials. For this purpose, sealed chambers with internal dimensions of approximately 60×60×60 cm3 were built within a protected and isolated laboratory environment, and stable air humidity and temperature levels were maintained. These chambers were also used for radon emanation reduction tests. The chambers were built in four major stages: (1) assembly of the walls using clay (red) bricks, concrete blocks, and mortar; (2) installation of plaster; (3) finishing of wall surface using lime; and (4) insulation of wall surface and finishing using paint. Radon measurements were performed using polycarbonate etched track detectors. By comparing the three layers applied to the masonry walls, it was concluded that only the last step (wall painting using acrylic varnish) reduced the radon emanation, by a factor of approximately 2. Samples of the construction materials (clay bricks and concrete blocks) were ground, homogenized, and subjected to gamma-ray spectrometry analysis to evaluate the activity concentrations of 226Ra, 232Th and 40K. The values for the index of the activity concentration (I), radium equivalent activity (Raeq), and external hazard index (Hext) showed that these construction materials could be used without restrictions or concern about the equivalent dose limit (1 mSv/year). Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Noticeable positive Doppler effect on optical bistability in an N-type active Raman gain atomic system

    International Nuclear Information System (INIS)

    Chang Zeng-Guang; Zhang Jing-Tao; Niu Yue-Ping; Gong Shang-Qing

    2012-01-01

    We theoretically investigate the Doppler effect on optical bistability in an N-type active Raman gain atomic system inside an optical ring cavity. It is shown that the Doppler effect can greatly enhance the dispersion and thus create the bistable behaviour or greatly increase the bistable region, which has been known as the positive Doppler effect on optical bistability. In addition, we find that a positive Doppler effect can change optical bistability from the hybrid dispersion-gain type to a dispersive type

  10. Effects of Drying Methods in Gaining of Extractive, Phenolic Content and Antioxidant Activity in Gynura Pseudochina (Lour.)

    OpenAIRE

    Rivai, Harrizul; Nurdin, Hazli; Suyani, Hamzar; Bakhtiar, Amri

    2010-01-01

    Effects of drying methods in gaining of extractive, phenolic content and antioxidant activity in Gynura pseudochina (Lour.) DC leaves have been investigated. The drying methods tested were air-drying at ± 25 oC, oven-drying at 40 OC, oven-drying at 60 OC, microwave oven-drying and fresh samples as control. Results revealed that drying of the fresh plant caused the decrease of extractive obtainability, phenolic content and antioxidant activity. There were significant differences among drying ...

  11. Aquatic Activities During Pregnancy Prevent Excessive Maternal Weight Gain and Preserve Birth Weight: A Randomized Clinical Trial.

    Science.gov (United States)

    Bacchi, Mariano; Mottola, Michelle F; Perales, Maria; Refoyo, Ignacio; Barakat, Ruben

    2018-03-01

    The aim of the present study was to examine the influence of a supervised and regular program of aquatic activities throughout gestation on maternal weight gain and birth weight. A randomized clinical trial. Instituto de Obstetricia, Ginecología y Fertilidad Ghisoni (Buenos Aires, Argentina). One hundred eleven pregnant women were analyzed (31.6 ± 3.8 years). All women had uncomplicated and singleton pregnancies; 49 were allocated to the exercise group (EG) and 62 to the control group (CG). The intervention program consisted of 3 weekly sessions of aerobic and resistance aquatic activities from weeks 10 to 12 until weeks 38 to 39 of gestation. Maternal weight gain, birth weight, and other maternal and fetal outcomes were obtained by hospital records. Student unpaired t test and χ 2 test were used; P values ≤.05 indicated statistical significance. Cohen's d was used to determinate the effect size. There was a higher percentage of women with excessive maternal weight gain in the CG (45.2%; n = 28) than in the EG (24.5%; n = 12; odds ratio = 0.39; 95% confidence interval: 0.17-0.89; P = .02). Birth weight and other pregnancy outcomes showed no differences between groups. Three weekly sessions of water activities throughout pregnancy prevents excessive maternal weight gain and preserves birth weight. The clinicaltrial.gov identifier: NCT 02602106.

  12. Active Surfaces and Interfaces of Soft Materials

    Science.gov (United States)

    Wang, Qiming

    A variety of intriguing surface patterns have been observed on developing natural systems, ranging from corrugated surface of white blood cells at nanometer scales to wrinkled dog skins at millimeter scales. To mimetically harness functionalities of natural morphologies, artificial transformative skin systems by using soft active materials have been rationally designed to generate versatile patterns for a variety of engineering applications. The study of the mechanics and design of these dynamic surface patterns on soft active materials are both physically interesting and technologically important. This dissertation starts with studying abundant surface patterns in Nature by constructing a unified phase diagram of surface instabilities on soft materials with minimum numbers of physical parameters. Guided by this integrated phase diagram, an electroactive system is designed to investigate a variety of electrically-induced surface instabilities of elastomers, including electro-creasing, electro-cratering, electro-wrinkling and electro-cavitation. Combing experimental, theoretical and computational methods, the initiation, evolution and transition of these instabilities are analyzed. To apply these dynamic surface instabilities to serving engineering and biology, new techniques of Dynamic Electrostatic Lithography and electroactive anti-biofouling are demonstrated.

  13. A theory of how active behavior stabilises neural activity: Neural gain modulation by closed-loop environmental feedback.

    Directory of Open Access Journals (Sweden)

    Christopher L Buckley

    2018-01-01

    Full Text Available During active behaviours like running, swimming, whisking or sniffing, motor actions shape sensory input and sensory percepts guide future motor commands. Ongoing cycles of sensory and motor processing constitute a closed-loop feedback system which is central to motor control and, it has been argued, for perceptual processes. This closed-loop feedback is mediated by brainwide neural circuits but how the presence of feedback signals impacts on the dynamics and function of neurons is not well understood. Here we present a simple theory suggesting that closed-loop feedback between the brain/body/environment can modulate neural gain and, consequently, change endogenous neural fluctuations and responses to sensory input. We support this theory with modeling and data analysis in two vertebrate systems. First, in a model of rodent whisking we show that negative feedback mediated by whisking vibrissa can suppress coherent neural fluctuations and neural responses to sensory input in the barrel cortex. We argue this suppression provides an appealing account of a brain state transition (a marked change in global brain activity coincident with the onset of whisking in rodents. Moreover, this mechanism suggests a novel signal detection mechanism that selectively accentuates active, rather than passive, whisker touch signals. This mechanism is consistent with a predictive coding strategy that is sensitive to the consequences of motor actions rather than the difference between the predicted and actual sensory input. We further support the theory by re-analysing previously published two-photon data recorded in zebrafish larvae performing closed-loop optomotor behaviour in a virtual swim simulator. We show, as predicted by this theory, that the degree to which each cell contributes in linking sensory and motor signals well explains how much its neural fluctuations are suppressed by closed-loop optomotor behaviour. More generally we argue that our results

  14. A theory of how active behavior stabilises neural activity: Neural gain modulation by closed-loop environmental feedback.

    Science.gov (United States)

    Buckley, Christopher L; Toyoizumi, Taro

    2018-01-01

    During active behaviours like running, swimming, whisking or sniffing, motor actions shape sensory input and sensory percepts guide future motor commands. Ongoing cycles of sensory and motor processing constitute a closed-loop feedback system which is central to motor control and, it has been argued, for perceptual processes. This closed-loop feedback is mediated by brainwide neural circuits but how the presence of feedback signals impacts on the dynamics and function of neurons is not well understood. Here we present a simple theory suggesting that closed-loop feedback between the brain/body/environment can modulate neural gain and, consequently, change endogenous neural fluctuations and responses to sensory input. We support this theory with modeling and data analysis in two vertebrate systems. First, in a model of rodent whisking we show that negative feedback mediated by whisking vibrissa can suppress coherent neural fluctuations and neural responses to sensory input in the barrel cortex. We argue this suppression provides an appealing account of a brain state transition (a marked change in global brain activity) coincident with the onset of whisking in rodents. Moreover, this mechanism suggests a novel signal detection mechanism that selectively accentuates active, rather than passive, whisker touch signals. This mechanism is consistent with a predictive coding strategy that is sensitive to the consequences of motor actions rather than the difference between the predicted and actual sensory input. We further support the theory by re-analysing previously published two-photon data recorded in zebrafish larvae performing closed-loop optomotor behaviour in a virtual swim simulator. We show, as predicted by this theory, that the degree to which each cell contributes in linking sensory and motor signals well explains how much its neural fluctuations are suppressed by closed-loop optomotor behaviour. More generally we argue that our results demonstrate the dependence

  15. Tests on 'radio-active' material

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The storage of radio-active waste from nuclear power stations is a well known problem and a subject for extensive investigation. In connection with the use of cement as storage material, tests were carried out on cement-filled 200-litre sheet-steel containers. In order to avoid contamination of the cement core by drilling sludge, any drilling operation must be carried out dry, i.e. without liquid cooling. Air-blast cooling was therefore used for the cooling of a diamond drill and also for the removal of swarf. (H.E.G.)

  16. Physical activity and psychological well-being in obese pregnant and postpartum women attending a weight-gain restriction programme.

    Science.gov (United States)

    Claesson, Ing-Marie; Klein, Sofia; Sydsjö, Gunilla; Josefsson, Ann

    2014-01-01

    the objective of the study was to compare the differences in psychological well-being and quality of life during pregnancy and post partum of obese physically active women and obese physically inactive women enroled in a weight gain restriction programme. We also wanted to explore whether physical activity influences weight change or health status during pregnancy. a prospective intervention study. antenatal care clinic. a total of 74 obese pregnant women in a physically active group and 79 obese women in a physically inactive group. the women kept diaries of their physical activity during pregnancy and answered the Beck Anxiety Inventory, the Edinburgh Postnatal Depression Scale and Medical Study Short-Form Health Survey in gestational weeks 15 and 35 and 11 weeks post partum. Physical activity was measured in metabolic equivalents. the physically active women experienced fewer depressive symptoms and estimated an improved quality of life during their pregnancies as measured by physical functioning, bodily pain, social functioning, role limitations due to emotional problems and general mental health as compared with the physically inactive women. There were no differences between the groups in gestational weight gain or weight change from early pregnancy to post partum or in prevalence of complications. physical activity among obese pregnant women provides better psychological well-being and improved quality of life, but does not prevent weight change. staff at Antenatal Care Clinics that face obese pregnant women, should encourage and emphasise the benefits of being physically active throughout pregnancy. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Information materials and communication activities of ARAO

    International Nuclear Information System (INIS)

    Kralj, M.; Zeleznik, N.; Mele, I.

    2002-01-01

    ARAO is a public agency responsible for implementing all aspects of radioactive waste management. Its most important mission is certainly the siting of a repository for all low and intermediate level waste in Slovenia. ARAO carries out different communication and information activities to improve the public acceptability of such a facility among the general public, local community, public opinion makers and decision makers. These activities include running of the Visitors' Centre, publishing various informative publications on radioactivity and radiation, nuclear technology and radioactive waste management. ARAO also supports study circles and local information media, has its own web site and communicates with journalists working for Slovenian magazines, newspapers, TV and radio stations. Communication and information activities are assigned about 10 % of the yearly budget of the agency. Most of the finance is spent on running the Visitors' Centre and on publishing information materials for school children, youngsters and teachers. Information on radioactivity and on the work of ARAO provided by the agency is intended to increase the public interest in nuclear issues and to prepare the foundation for an informed and responsible decision on the radioactive waste repository in Slovenia. ARAO has also implemented direct communication, such as workshops, study circles and representations for the local community leadership, and these activities will be intensified in the near future.(author)

  18. Bibliographic data base for low activation materials

    International Nuclear Information System (INIS)

    Alenina, M.V.; Kolotov, V.P.; Ivanov, L.I.

    2007-01-01

    Full text of publication follows: The analysis of the publications dealing with development of low-activation materials for fusion technology demonstrates that the period of information doubling is about 5-6 years. Such high rate usually is characteristic of the actively developing field of science. To develop an useful instrument for analysis and systematization of the available data a computer based bibliographic system has been developed some time ago. Recently the engine of the system has been significantly modernized. The bibliographic system is based on using of MS SQL server data base which includes main bibliographic information including abstracts. The most important feature of the system is that full-text abstracts searching capabilities are appended with indexing of information by experts to increase its definition. The experts indexes cover the following topics: - Main problems; - Software and methods for calculation; - Libraries of nuclear data; - Spectrum of neutrons for different construction parts of fusion reactor; - Low activation materials; - Technology of production; - Radiation effects; - Utilization of radiation waste; - Estimation of risks; - Designs of fusion reactor; - Nuclear transmutations; - Equipment used for investigations. The primary data base is filling/appending by periodical queries to different bibliographic data bases (INIS, COMPEMDEX and others) via suitable Internet providers including strict analysis of the income information to remove a possible 'information noise' and following data indexing by experts. The data base contains references since 1976 year (when first works in this area have been fulfilled) and until now. The bibliographic system is accessible by means of Internet using different forms developed for queries (http://www.geokhi.ru/~lam_db). (authors)

  19. Bibliographic data base for low activation materials

    Energy Technology Data Exchange (ETDEWEB)

    Alenina, M.V.; Kolotov, V.P. [Vernadsky Institute of Geochemistry and Analytical Chemistry, Moscow (Russian Federation); Ivanov, L.I. [A.A. Baikov Institute of Metallurgy and Science of Materials, Russian Academy of Sciences, Moscow (Russian Federation)

    2007-07-01

    Full text of publication follows: The analysis of the publications dealing with development of low-activation materials for fusion technology demonstrates that the period of information doubling is about 5-6 years. Such high rate usually is characteristic of the actively developing field of science. To develop an useful instrument for analysis and systematization of the available data a computer based bibliographic system has been developed some time ago. Recently the engine of the system has been significantly modernized. The bibliographic system is based on using of MS SQL server data base which includes main bibliographic information including abstracts. The most important feature of the system is that full-text abstracts searching capabilities are appended with indexing of information by experts to increase its definition. The experts indexes cover the following topics: - Main problems; - Software and methods for calculation; - Libraries of nuclear data; - Spectrum of neutrons for different construction parts of fusion reactor; - Low activation materials; - Technology of production; - Radiation effects; - Utilization of radiation waste; - Estimation of risks; - Designs of fusion reactor; - Nuclear transmutations; - Equipment used for investigations. The primary data base is filling/appending by periodical queries to different bibliographic data bases (INIS, COMPEMDEX and others) via suitable Internet providers including strict analysis of the income information to remove a possible 'information noise' and following data indexing by experts. The data base contains references since 1976 year (when first works in this area have been fulfilled) and until now. The bibliographic system is accessible by means of Internet using different forms developed for queries (http://www.geokhi.ru/{approx}lam{sub d}b). (authors)

  20. Rapid binge-like eating and body weight gain driven by zona incerta GABA neuron activation.

    Science.gov (United States)

    Zhang, Xiaobing; van den Pol, Anthony N

    2017-05-26

    The neuronal substrate for binge eating, which can at times lead to obesity, is not clear. We find that optogenetic stimulation of mouse zona incerta (ZI) γ-aminobutyric acid (GABA) neurons or their axonal projections to paraventricular thalamus (PVT) excitatory neurons immediately (in 2 to 3 seconds) evoked binge-like eating. Minimal intermittent stimulation led to body weight gain; ZI GABA neuron ablation reduced weight. ZI stimulation generated 35% of normal 24-hour food intake in just 10 minutes. The ZI cells were excited by food deprivation and the gut hunger signal ghrelin. In contrast, stimulation of excitatory axons from the parasubthalamic nucleus to PVT or direct stimulation of PVT glutamate neurons reduced food intake. These data suggest an unexpected robust orexigenic potential for the ZI GABA neurons. Copyright © 2017, American Association for the Advancement of Science.

  1. Experiences Gained from Radiation Protection Activities in Egypt and Saudi Arabia

    International Nuclear Information System (INIS)

    Kamal, S. M.

    2004-01-01

    My official duties and responsibilities in Egypt and Saudi Arabia as radiation safety officer, qualified expert and head of dosimetry section covered the specified branch of radiation protection. This branch may be called Applied Radiation Protection. This branch covers all aspects of personal and environmental dosimetry and monitoring, as well as, radiation measurements and shielding. This branch has been implemented at many universities, medical centers and nuclear organizations in both Egypt and Saudi Arabia. As a result, three subjects have been highlighted 1] Radiation Protection of workers, public and environment, 2) Safety of radioactive materials to ensure its control and 3) Security from unauthorized removal. A program has been proposed as (RPSS program). In this program, radiation workers are responsible for the security of all radioactive materials in their possession including radioactive waste in storage cabinets and sources left unattended on laboratory benches. Occupational radiation exposures have been kept below dose limits at all radiation areas by training increased experience and ability of radiation workers. All radioactive materials that are not in locked storage are under constant surveillance and immediate control at all times by Radiation Safety Officer (RSO) or medical physicist departments. Precautionary measures serve as a guide to safe operations in handling radioactive materials and radiation sources. Certain restricted areas, which contain large quantities of radioactive materials, required additional security measures. Implementation of this program led to secure of radioactive materials from unauthorized removal or access, public health, maintaining exposures as low as reasonably achievable and promoting a protective safe working environment with no contamination. It is recommended to include this program in Radiation Protection Manual and Emergency preparedness procedures at academic institutions, nuclear research facilities and

  2. Effect of intrinsic-gain fluctuations on quantum noise of phosphor materials used in medical X-ray imaging

    International Nuclear Information System (INIS)

    Kalivas, N.; Costaridou, L.; Panayiotakis, G.; Nomicos, C.D.

    1999-01-01

    The quality of a medical image depends, among other parameters, on quantum noise. Quantum noise is affected by the fluctuations in the number of optical quanta produced within the phosphor, per absorbed X-ray (i.e. phosphor intrinsic-gain fluctuations). This effect is considered by means of a factor, called in this study intrinsic-gain noise factor, IGNF(E). In existing theoretical models of quantum noise, the corresponding factor is taken to be equal to one. In this paper, an expression that accounts for the coefficient of variation of the phosphor intrinsic gain is introduced. This expression takes into account the process of electron-hole pair conversion to optical photons and the frequency distribution function of the emitted optical photon energy. Subsequently IGNF(E) is expressed in terms of this coefficient of variation. IGNF(E) has been calculated for several phosphors and for various energies. For all medical X-ray energies studied, phosphors that exhibit a high relative fluctuation of emitted optical photon energy, IGNF(E) exceeds by 2% to over 17% the corresponding factor of the existing theoretical models of quantum noise. (orig.)

  3. Muscle activity during functional coordination training: implications for strength gain and rehabilitation

    DEFF Research Database (Denmark)

    Jørgensen, Marie Birk; Andersen, Lars Louis; Kirk, Niels

    2010-01-01

    The purpose of this study was to evaluate if different types, body positions, and levels of progression of functional coordination exercises can provide sufficiently high levels of muscle activity to improve strength of the neck, shoulder, and trunk muscles. Nine untrained women were familiarized...... to the maximal EMG activity during maximal voluntary contractions, and a p value 60% of maximal EMG activity). Type of exercise played a significant role...

  4. Do all sedentary activities lead to weight gain: sleep does not.

    Science.gov (United States)

    Chaput, Jean-Philippe; Klingenberg, Lars; Sjödin, Anders

    2010-11-01

    To discuss the benefits of having a good night's sleep for body weight stability. Experimental studies have shown that short-term partial sleep restriction decreases glucose tolerance, increases sympathetic tone, elevates cortisol concentrations, decreases the satiety hormone leptin, increases the appetite-stimulating hormone ghrelin, and increases hunger and appetite. Short sleep duration might increase the risk of becoming obese, because it does not allow the recovery of a hormonal profile facilitating appetite control. Lack of sleep could also lead to weight gain and obesity by increasing the time available for eating and by making the maintenance of a healthy lifestyle more difficult. Furthermore, the increased fatigue and tiredness associated with sleeping too little could lessen one's resolve to follow exercise regimens. Short sleep duration appears to be a novel and independent risk factor for obesity. With the growing prevalence of chronic sleep restriction, any causal association between reduced sleep and obesity would have substantial importance from a public health standpoint. Future research is needed to determine whether sleep extension in sleep-deprived obese individuals will influence appetite control and/or reduce the amount of body fat.

  5. Characterisation and properties of alkali activated pozzolanic materials

    Science.gov (United States)

    Bordeian, Georgeta Simona

    Many of the waste materials produced from modem heavy industries are pozzalans, which develop cementitious properties when finely divided in the presence of free lime. This property allows a potential industrial use for this waste as a cement replacement material in concrete. An example of such a waste material is blast furnace slag from the smelting of iron and steel. The US produces 26 million tons of blast furnace slag annually. Most of the slag is slowly cooled in air and it makes a poor pozzolan. Only 1.6 million tons of the slag is available in the granulated form, which is suitable as a cementitious and pozzolanic admixture. Most European countries are well endowed with coal-fired power stations and this produces fly and bottom ash, flue gas desulphurisation (FGD) gypsum. However, less than 25% of the total ash from power stations has found an industrial use mainly in cement and concrete industry. This creates a massive waste-disposal problem. Disposal of unused fly ash in open tips and ponds, for example, creates pollution problems since the drainage of effluents from the ash in the deposit ponds threaten water supplies by polluting the ground water with traces of toxic chemicals.Recent research has concentrated on the alkali activation of waste pozzolanic materials, especially ground blast furnace slag. This thesis has investigated the alkali activation of low calcium fly ashes. These form very poor pozzolans and the alkali activation of the fly ash offers the opportunity for the large scale use of fly ash. Water glass was selected as a suitable activator for the fly ash. A comprehensive series of tests have been carried out to gain information on the effect of different parameters, such as proportion and composition of the constituent materials, curing conditions and casting methods, in developing high performance construction materials. Laboratory investigations were carried out to determine the following characteristics of alkali activated materials

  6. Enhancing Diversity in Undergraduate Science: Self-Efficacy Drives Performance Gains with Active Learning

    OpenAIRE

    Ballen, Cissy J.; Wieman, Carl; Salehi, Shima; Searle, Jeremy B.; Zamudio, Kelly R.

    2017-01-01

    Efforts to retain underrepresented minority (URM) students in science, technology, engineering, and mathematics (STEM) have shown only limited success in higher education, due in part to a persistent achievement gap between students from historically underrepresented and well-represented backgrounds. To test the hypothesis that active learning disproportionately benefits URM students, we quantified the effects of traditional versus active learning on student academic performance, science self...

  7. Rheology of Cementitious Materials: Alkali-Activated Materials or Geopolymers

    Directory of Open Access Journals (Sweden)

    Puertas F.

    2018-01-01

    Understanding and controlling the rheology of the AAMs systems will ultimately determine whether they can be implemented in the market, and will open up greater competitive possibilities in a crisis-affected sector. A systematic study of the factors that affect the rheological properties of AAMs (pastes, mortars and concretes is therefore necessary in order to ultimately develop more resistant and durable materials.

  8. Activation analysis of biological materials at the Activation Analysis Centre

    International Nuclear Information System (INIS)

    Kukula, F.; Obrusnik, I.; Simkova, M.; Kucera, J.; Krivanek, M.

    1976-01-01

    A review is presented of the work of the Activation Analysis Centre of the Nuclear Research Institute for different fields of the Czechoslovak economy, aimed primarily at analyzing biological materials with the purpose of determining the contents of the so-called vital trace elements and of elements which already have a toxic effect on the organism in trace concentrations. Another important field of research is the path of trace elements from the environment to the human organism. A destructive method for the simultaneous determination of 12 trace elements in 11 kinds of human tissue has been studied. (Z.M.)

  9. Arctigenin Inhibits Adipogenesis by Inducing AMPK Activation and Reduces Weight Gain in High-Fat Diet-Induced Obese Mice.

    Science.gov (United States)

    Han, Yo-Han; Kee, Ji-Ye; Park, Jinbong; Kim, Hye-Lin; Jeong, Mi-Young; Kim, Dae-Seung; Jeon, Yong-Deok; Jung, Yunu; Youn, Dong-Hyun; Kang, JongWook; So, Hong-Seob; Park, Raekil; Lee, Jong-Hyun; Shin, Soyoung; Kim, Su-Jin; Um, Jae-Young; Hong, Seung-Heon

    2016-09-01

    Although arctigenin (ARC) has been reported to have some pharmacological effects such as anti-inflammation, anti-cancer, and antioxidant, there have been no reports on the anti-obesity effect of ARC. The aim of this study is to investigate whether ARC has an anti-obesity effect and mediates the AMP-activated protein kinase (AMPK) pathway. We investigated the anti-adipogenic effect of ARC using 3T3-L1 pre-adipocytes and human adipose tissue-derived mesenchymal stem cells (hAMSCs). In high-fat diet (HFD)-induced obese mice, whether ARC can inhibit weight gain was investigated. We found that ARC reduced weight gain, fat pad weight, and triglycerides in HFD-induced obese mice. ARC also inhibited the expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα) in in vitro and in vivo. Furthermore, ARC induced the AMPK activation resulting in down-modulation of adipogenesis-related factors including PPARγ, C/EBPα, fatty acid synthase, adipocyte fatty acid-binding protein, and lipoprotein lipase. This study demonstrates that ARC can reduce key adipogenic factors by activating the AMPK in vitro and in vivo and suggests a therapeutic implication of ARC for obesity treatment. J. Cell. Biochem. 117: 2067-2077, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Experience gained from high heat flux actively cooled PFCs in Tore Supra

    International Nuclear Information System (INIS)

    Grosman, A.; Bayetti, P.; Brosset, C.; Bucalossi, J.; Cordier, J.J.; Durocher, A.; Escourbiac, F.; Ghendrih, Ph.; Guilhem, D.; Gunn, J.; Loarer, T.; Lipa, M.; Mitteau, R.; Pegourie, B.; Reichle, R.; Schlosser, J.; Tsitrone, E.; Vallet, J.C.

    2005-01-01

    The implementation of actively cooled high heat flux plasma facing components (PFCs) is one of the major ingredients required for operating the Tore Supra tokamak with very long pulses. A pioneering activity has been developed in this field from the very beginning of the device operation that is today culminating with the routine operation of an actively cooled toroidal pumped limiter (TPL) capable to sustain up to 10 MW/m 2 of nominal convected heat flux. Technical information is drawn from the whole development up to the industrialisation and focuses on a number of critical issues, such as bonding technology analysis, manufacture processes, repair processes, destructive and non-destructive testing. The actual experience in Tore Supra allows to address the question of D retention on carbon walls. Redeposition on surfaces without plasma flux is suspected to cause the final 'burial' of about half of the injected gas during long discharges

  11. Enhancing Diversity in Undergraduate Science: Self-Efficacy Drives Performance Gains with Active Learning

    Science.gov (United States)

    Ballen, Cissy J.; Wieman, Carl; Salehi, Shima; Searle, Jeremy B.; Zamudio, Kelly R.

    2017-01-01

    Efforts to retain underrepresented minority (URM) students in science, technology, engineering, and mathematics (STEM) have shown only limited success in higher education, due in part to a persistent achievement gap between students from historically underrepresented and well-represented backgrounds. To test the hypothesis that active learning…

  12. Fundamental Properties and Practical Application of Active Microwave Metamaterials Incorporating Gain Devices

    Science.gov (United States)

    2017-02-22

    person shall be subject to any penalty for failing to comply with a collection of information   if it does not display a currently valid OMB control... transmission line and an active volumetric metamaterial. These designs have been extended to THz frequency range. In addition, we have investigated the non...circuits,” IEEE International Microwave Symposium, Phoenix, Arizona, May 17-22, 2015. [7] Q. Tang, and H. Xin, “Stability of Tunnel Diode based Negative

  13. Disposal of activated fusion wall materials

    International Nuclear Information System (INIS)

    Blink, J.A.; Dorn, D.W.; Maninger, R.C.

    1983-08-01

    We have used NRC's low-level waste disposal regulation (10CFR61) to classify activated fusion reactor structural materials. The limits set by the NRC in 10CFR61 will require extremely expensive steels with degraded properties, even when the limits are adjusted to give credit for use of an expensive hot waste disposal facility. Both the expense and the poorer properties could have a negative impact on reactor safety, thus subverting the overall goals of the NRC family of regulations. Following this initial study, we have examined the methodology used by the NRC to set waste concentration limits. For a long-lived gamma emitter like 94 Nb, direct gamma dose to an intruding home builder dominates the limit setting process. Of all the tests applied to the waste, the controlling test which sets the lowest limit ignores all the engineered intrusion barriers which are themselves required by the same regulation. If even a small fraction of the barriers remain intact (an extremely likely event), the 94 Nb limit could be increased from the 0.2 Ci/m 3 in 10CFR61 to 1100 Ci/m 3 without exceeding the limits set for personnel exposure. Similarly, cautious application of the 10CFR61 methodology to other radioisotopes of interest to fusion designers will result in limits which are more in line with the unique nature of fusion energy

  14. Effect of diet and physical activity based interventions in pregnancy on gestational weight gain and pregnancy outcomes

    DEFF Research Database (Denmark)

    2017-01-01

    were supplemented with study level data from studies that did not provide IPD, the overall effect was similar, with stronger evidence of benefit for gestational diabetes (0.76, 0.65 to 0.89, I2=36.8%; 59 studies, 16 885 women).Conclusion Diet and physical activity based interventions during pregnancy......Objective To synthesise the evidence on the overall and differential effects of interventions based on diet and physical activity during pregnancy, primarily on gestational weight gain and maternal and offspring composite outcomes, according to women's body mass index, age, parity, ethnicity...... Randomised trials on diet and physical activity based interventions in pregnancy.Data synthesis Statistical models accounted for clustering of participants within trials and heterogeneity across trials leading to summary mean differences or odds ratios with 95% confidence intervals for the effects overall...

  15. Effect of diet and physical activity based interventions in pregnancy on gestational weight gain and pregnancy outcomes

    DEFF Research Database (Denmark)

    2017-01-01

    Randomised trials on diet and physical activity based interventions in pregnancy.Data synthesis Statistical models accounted for clustering of participants within trials and heterogeneity across trials leading to summary mean differences or odds ratios with 95% confidence intervals for the effects overall......Objective To synthesise the evidence on the overall and differential effects of interventions based on diet and physical activity during pregnancy, primarily on gestational weight gain and maternal and offspring composite outcomes, according to women's body mass index, age, parity, ethnicity...... were supplemented with study level data from studies that did not provide IPD, the overall effect was similar, with stronger evidence of benefit for gestational diabetes (0.76, 0.65 to 0.89, I2=36.8%; 59 studies, 16 885 women).Conclusion Diet and physical activity based interventions during pregnancy...

  16. Experience gained upon industrial application of on-line activation analysis in flotation

    International Nuclear Information System (INIS)

    Braun, H.; Riffel, F.

    1979-01-01

    At the Karlsruhe Nuclear Research Center an anlyzer was developed which allows continuous evaluation of the valuable minerals content in process streams. Experience is reported which has been gathered in several weeks of industrial application in a fluorspar flotation plant, the first industrial scale application of on-line activation analysis in Europe. The use has shown that with the equipment presented on-line monitoring with the desired accuracy is possible of all the strategically important points. This is of considerable importance for the economy of the process. (orig.) [de

  17. Comparative studies on extracts from Hericium erinaceus by different polarity reagents to gain higher antioxidant activities.

    Science.gov (United States)

    Jiang, Shengjuan; Wang, Yuliang; Zhang, Xiaolong

    2016-07-01

    Hericium erinaceus (H. erinaceus) is a source of exogenous antioxidants that has been traditionally used in China for the prevention and treatment of oxidative stress-associated disease. In the present study, the bioactive compounds of H. erinaceus were extracted with the following eight representative reagents: n-Hexane, xylene, chloroform, anhydrous ether, ethyl acetate, acetone, anhydrous ethanol and distilled water. The in vitro antioxidant activities were also evaluated. All of the extracted compounds exhibited reducing power and scavenging activity against 1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion free radicals. In addition, the antioxidant capacities varied with the used chemical reagents and exhibited dose-dependent effects. Extracts from anhydrous ethanol, chloroform and acetone were capable of inhibiting lipid peroxidation. The anhydrous ethanol extracts were observed to have significant levels of antioxidant compounds since they had a strong reducing power, high scavenging rates against DPPH and superoxide anion-free radicals (>90%), and high inhibition rates on lipid peroxidation (>60%). The present study will provide reference data for the antioxidant applications of H. erinaceus in pharmaceutical use and disease prevention.

  18. Impact of the Excitation Source and Plasmonic Material on Cylindrical Active Coated Nano-Particles

    Directory of Open Access Journals (Sweden)

    Richard W. Ziolkowski

    2011-09-01

    Full Text Available Electromagnetic properties of cylindrical active coated nano-particles comprised of a silica nano-cylinder core layered with a plasmonic concentric nano-shell are investigated for potential nano-sensor applications. Particular attention is devoted to the near-field properties of these particles, as well as to their far-field radiation characteristics, in the presence of an electric or a magnetic line source. A constant frequency canonical gain model is used to account for the gain introduced in the dielectric part of the nano-particle, whereas three different plasmonic materials (silver, gold, and copper are employed and compared for the nano-shell layers.

  19. Impurity concentration limits and activation in fusion reactor structural materials

    International Nuclear Information System (INIS)

    Zucchetti, M.

    1991-01-01

    This paper examines waste management problems related to impurity activation in first-wall, shield, and magnet materials for fusion reactors. Definitions of low activity based on hands-on recycling, remote recycling, and shallow land burial waste management criteria are discussed. Estimates of the impurity concentration in low-activation materials (elementally substituted stainless steels and vanadium alloys) are reported. Impurity activation in first-wall materials turns out to be critical after a comparison of impurity concentration limits and estimated levels. Activation of magnet materials is then considered: Long-term activity is not a concern, while short-term activity is. In both cases, impurity activation is negligible. Magnet materials, and all other less flux-exposed materials, have no practical limitation on impurities in terms of induced radioactivity

  20. Health/Service Providers' Perspectives on Barriers to Healthy Weight Gain and Physical Activity in Pregnant, Urban First Nations Women.

    Science.gov (United States)

    Darroch, Francine E; Giles, Audrey R

    2016-01-01

    The purpose of this article is to examine health/service providers' perspectives of barriers to healthy weight gain and physical activity for urban, pregnant First Nations women in Ottawa, Canada. Through the use of semi-structured interviews, we explored 15 health/service providers' perspectives on the complex barriers their clients face. By using a postcolonial feminist lens and a social determinants of health framework, we identified three social determinants of health that the health/service providers believed to have the greatest influence on their clients' weight gain and physical activity during pregnancy: poverty, education, and colonialism. Our findings are then contextualized within existing Statistics Canada and the Ottawa Neighbourhood Study data. We found that health/service providers are in a position to challenge colonial relations of power. We conclude by urging health/service providers, researchers, and policymakers alike to take into consideration the ways in which these social determinants of health and their often synergistic effects affect urban First Nations women during pregnancy. © The Author(s) 2015.

  1. Insights gained from relating cumulative seismic moments to fluid injection activities

    Science.gov (United States)

    McGarr, A.; Barbour, A. J.

    2017-12-01

    The three earthquakes with magnitudes of 5 or greater that were induced in Oklahoma during 2016 motivated efforts to improve our understanding of how fluid injection operations are related to earthquake activity. In this study, we have addressed the question of whether the volume of fluid injected down wells within 10 km of the mainshock of an induced earthquake sequence can account for its total moment release. Specifically, is the total moment release equal to, or less than, twice the product of the shear modulus and the total volume injected (McGarr, JGR, 2014, equation 7)? In contrast to McGarr's (2014, equation 13) relationship for the maximum moment, M0(max), the relationship for the total moment release has the advantage of being independent of the magnitude distribution. We find that the three sequences in Oklahoma in 2016, M5.1 Fairview, M5.8 Pawnee, M5.0 Cushing, and the 2011 M5.7 Prague sequence all adhere to this relationship. We also found that eight additional sequences of earthquakes induced by various fluid injection activities, widely distributed worldwide, show the same relationship between total moment-release and injected volume. Thus, for injected volumes ranging from 103 up to 107 cubic m, the moment release of an induced earthquake sequence appears to be similarly limited. These results imply that M0(max) for a sequence induced by fluid injection could be as high as twice the product of the shear modulus and the injected volume if the mainshock in the sequence accounts for nearly all of the total moment, as was the case for the 2016 Pawnee M5.8 mainshock. This new upper bound for maximum moment is twice what was proposed by McGarr (2014, equation 13). Our new results also support the assumption in our analysis that the induced earthquake rupture is localized to the seismogenic region that is weakened owing to a pore pressure increase of the order of a seismic stress drop.

  2. Active flow control insight gained from a modified integral boundary layer equation

    Science.gov (United States)

    Seifert, Avraham

    2016-11-01

    Active Flow Control (AFC) can alter the development of boundary layers with applications (e.g., reducing drag by separation delay or separating the boundary layers and enhancing vortex shedding to increase drag). Historically, significant effects of steady AFC methods were observed. Unsteady actuation is significantly more efficient than steady. Full-scale AFC tests were conducted with varying levels of success. While clearly relevant to industry, AFC implementation relies on expert knowledge with proven intuition and or costly and lengthy computational efforts. This situation hinders the use of AFC while simple, quick and reliable design method is absent. An updated form of the unsteady integral boundary layer (UIBL) equations, that include AFC terms (unsteady wall transpiration and body forces) can be used to assist in AFC analysis and design. With these equations and given a family of suitable velocity profiles, the momentum thickness can be calculated and matched with an outer, potential flow solution in 2D and 3D manner to create an AFC design tool, parallel to proven tools for airfoil design. Limiting cases of the UIBL equation can be used to analyze candidate AFC concepts in terms of their capability to modify the boundary layers development and system performance.

  3. Effects of physical activity during pregnancy and gestational weight gain on newborn weight and length at birth in Warmińsko-Mazurskie province.

    Science.gov (United States)

    Przybyłowicz, Katarzyna; Przybyłowicz, Mariusz; Grzybiak, Marek; Janiszewska, Katarzyna

    2014-01-01

    Epidemiological research has identified a relationship between maternal physical activity, early nutrition and infant birth weight with likelihood of developing future diseases. The aim of the study was to determine a relationship between gestational weight gain and physical activity during pregnancy to the nutritional status of newborns. The presented study was conducted in the period from February 2010 until November 2012 in the gynecological and obstetric clinics in Warmińsko-Mazurskie voivodeship with various levels of reference. The research subjects included 510 women in the puerperal period aged 18-36. The scope of the research included an assessment of the selected anthropometric parameters of both pregnant women (body mass, height, BMI, gestational weight gain) and newborns (infant birth weight, infant length, Ponderal Index), as well as an analysis of the connections between the gestational weight gain, physical activity during pregnancy and anthropometric parameters of newborns. In the study group there was a significant percentage of women characterised by an inactive lifestyle and excessive gestational weight gain. There were significantly higher neonatal birth anthropometric parameters in women with abnormal excessive gestational weight gain than in women with normal and inappropriate - low gestational weight gain. The highest percentage of women with appropriate weight gain was observed in the group of women who are physically active, although this requires confirmation in larger population. Our studies have not shown statistically significant differences between the gestational weight gain and nutritional status of newborns in relation to the level of physical activity of pregnant women.

  4. Influence of pre-pregnancy leisure time physical activity on gestational and postpartum weight gain and birth weight - a cohort study.

    Science.gov (United States)

    Hegaard, Hanne Kristine; Rode, Line; Katballe, Malene Kjær; Langberg, Henning; Ottesen, Bent; Damm, Peter

    2017-08-01

    In order to examine the association between pre-pregnancy leisure time physical activities and gestational weight gain, postpartum weight gain and birth weight, we analysed prospectively collected data from 1827 women with singleton term pregnancies. Women were categorised in groups of sedentary women, light exercisers, moderate exercisers and competitive athletes. The results showed that sedentary women on average gained 14.1 kg during pregnancy, whereas light exercisers gained 13.7 kg, moderate exercisers gained 14.3 kg and competitive athletes 16.1 kg. Competitive athletes had an increased risk of having a gestational weight gain above Institute of Medicine (IOM) recommendations with an odds ratio of 2.60 (1.32-5.15) compared to light exercisers. However, birth weight and one year postpartum weight was similar for all four groups. Thus, although competitive athletes gain more weight than recommended during pregnancy, this may not affect birth weight or postpartum weight. Impact statement What is already known on this subjectPrevious studies have found that increased pre-pregnancy physical activity is associated with lower gestational weight gain during the last trimester, but showed no association between the pre-pregnancy level of physical activity and mean birth weight. What the results of this study addWe found that women classified as competitive exercisers had a 2.6-fold increased risk of gaining more weight than recommended compared to light exercisers. Nearly 6 out of 10 women among the competitive exercisers gained more weight than recommended by IOM. Surprisingly, this did not appear to increase birth weight or post-partum weight gain, but other adverse effects cannot be excluded. What the implications are of these findings for clinical practice and/or further researchIn the clinical practice it may be relevant to focus on and advise pre-pregnancy competitive exercisers in order to prevent excessive gestational weight gain.

  5. Thermoregulation of water foraging honeybees--balancing of endothermic activity with radiative heat gain and functional requirements.

    Science.gov (United States)

    Kovac, Helmut; Stabentheiner, Anton; Schmaranzer, Sigurd

    2010-12-01

    Foraging honeybees are subjected to considerable variations of microclimatic conditions challenging their thermoregulatory ability. Solar heat is a gain in the cold but may be a burden in the heat. We investigated the balancing of endothermic activity with radiative heat gain and physiological functions of water foraging Apis mellifera carnica honeybees in the whole range of ambient temperatures (T(a)) and solar radiation they are likely to be exposed in their natural environment in Middle Europe. The mean thorax temperature (T(th)) during foraging stays was regulated at a constantly high level (37.0-38.5 °C) in a broad range of T(a) (3-30 °C). At warmer conditions (T(a)=30-39 °C) T(th) increased to a maximal level of 45.3 °C. The endothermic temperature excess (difference of T(body)-T(a) of living and dead bees) was used to assess the endogenously generated temperature elevation as a correlate of energy turnover. Up to a T(a) of ∼30 °C bees used solar heat gain for a double purpose: to reduce energetic expenditure and to increase T(th) by about 1-3 °C to improve force production of flight muscles. At higher T(a) they exhibited cooling efforts to get rid of excess heat. A high T(th) also allowed regulation of the head temperature high enough to guarantee proper function of the bees' suction pump even at low T(a). This shortened the foraging stays and this way reduced energetic costs. With decreasing T(a) bees also reduced arrival body weight and crop loading to do both minimize costs and optimize flight performance. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Replacing Non-Active Video Gaming by Active Video Gaming to Prevent Excessive Weight Gain in Adolescents

    NARCIS (Netherlands)

    Simons, M.; Brug, J.; Chinapaw, M.J.M.; Boer, de M.; Seidell, J.; Vet, de E.

    2015-01-01

    Objective - The aim of the current study was to evaluate the effects of and adherence to an active video game promotion intervention on anthropometrics, sedentary screen time and consumption of sugar-sweetened beverages and snacks among non-active video gaming adolescents who primarily were of

  7. Replacing non-active video gaming by active video gaming to prevent excessive weight gain in adolescents

    NARCIS (Netherlands)

    Simons, M.; Brug, J.; Chinapaw, M.J.M.; Boer, M. de; Seidell, J.; Vet, E. de

    2015-01-01

    Objective: The aim of the current study was to evaluate the effects of and adherence to an active video game promotion intervention on anthropometrics, sedentary screen time and consumption of sugar-sweetened beverages and snacks among non-active video gaming adolescents who primarily were of

  8. Gain-of-function mutant p53 activates small GTPase Rac1 through SUMOylation to promote tumor progression.

    Science.gov (United States)

    Yue, Xuetian; Zhang, Cen; Zhao, Yuhan; Liu, Juan; Lin, Alan W; Tan, Victor M; Drake, Justin M; Liu, Lianxin; Boateng, Michael N; Li, Jun; Feng, Zhaohui; Hu, Wenwei

    2017-08-15

    Tumor suppressor p53 is frequently mutated in human cancer. Mutant p53 often promotes tumor progression through gain-of-function (GOF) mechanisms. However, the mechanisms underlying mutant p53 GOF are not well understood. In this study, we found that mutant p53 activates small GTPase Rac1 as a critical mechanism for mutant p53 GOF to promote tumor progression. Mechanistically, mutant p53 interacts with Rac1 and inhibits its interaction with SUMO-specific protease 1 (SENP1), which in turn inhibits SENP1-mediated de-SUMOylation of Rac1 to activate Rac1. Targeting Rac1 signaling by RNAi, expression of the dominant-negative Rac1 (Rac1 DN), or the specific Rac1 inhibitor NSC23766 greatly inhibits mutant p53 GOF in promoting tumor growth and metastasis. Furthermore, mutant p53 expression is associated with enhanced Rac1 activity in clinical tumor samples. These results uncover a new mechanism for Rac1 activation in tumors and, most importantly, reveal that activation of Rac1 is an unidentified and critical mechanism for mutant p53 GOF in tumorigenesis, which could be targeted for therapy in tumors containing mutant p53. © 2017 Yue et al.; Published by Cold Spring Harbor Laboratory Press.

  9. (Bio)hybrid materials based on optically active particles

    Science.gov (United States)

    Reitzig, Manuela; Härtling, Thomas; Opitz, Jörg

    2014-03-01

    In this contribution we provide an overview of current investigations on optically active particles (nanodiamonds, upconversion phospors) for biohybrid and sensing applications. Due to their outstanding properties nanodiamonds gain attention in various application elds such as microelectronics, optical monitoring, medicine, and biotechnology. Beyond the typical diamond properties such as high thermal conductivity and extreme hardness, the carbon surface and its various functional groups enable diverse chemical and biological surface functionalization. At Fraunhofer IKTS-MD we develop a customization of material surfaces via integration of chemically modi ed nanodiamonds at variable surfaces, e.g bone implants and pipelines. For the rst purpose, nanodiamonds are covalently modi ed at their surface with amino or phosphate functionalities that are known to increase adhesion to bone or titanium alloys. The second type of surface is approached via mechanical implementation into coatings. Besides nanodiamonds, we also investigate the properties of upconversion phosphors. In our contribution we show how upconversion phosphors are used to verify sterilization processes via a change of optical properties due to sterilizing electron beam exposure.

  10. Experience gained with certification of instruments for the system for nuclear material physical protection, accounting, and control

    International Nuclear Information System (INIS)

    Gus'kov, O.M.; Egorov, V.V.; Morozov, O.S.; Novikov, V.M.

    1999-01-01

    Results of the tests have confirmed the expedience of certification of the equipment, especially imported items. For the use of imported equipment at Russian facilities, it is justified to accommodate the accompanying documents thereto for the Russian standards. Equipment items shipped to Russia should be prepared for the certification tests and/or operation. When taking decision on the certification of imported equipment, it is expedient to preliminarily estimate the instrument's parameters and its operation in Russia. To solve the question whether the imported equipment is usable for Russia and what engineering support and maintenance is needed for its operation, it would be justified to create the Center for engineering support of instruments to be used for nuclear material protection, control and accounting on the basis of one of institutes dealing with the development of instruments for these application [ru

  11. The Use of Group Activities in Introductory Biology Supports Learning Gains and Uniquely Benefits High-Achieving Students

    Directory of Open Access Journals (Sweden)

    Gili Marbach-Ad

    2016-12-01

    Full Text Available This study describes the implementation and effectiveness of small-group active engagement (GAE exercises in an introductory biology course (BSCI207 taught in a large auditorium setting. BSCI207 (Principles of Biology III—Organismal Biology is the third introductory core course for Biological Sciences majors. In fall 2014, the instructors redesigned one section to include GAE activities to supplement lecture content. One section (n = 198 employed three lectures per week. The other section (n = 136 replaced one lecture per week with a GAE class. We explored the benefits and challenges associated with implementing GAE exercises and their relative effectiveness for unique student groups (e.g., minority students, high- and low-grade point average [GPA] students. Our findings show that undergraduates in the GAE class exhibited greater improvement in learning outcomes than undergraduates in the traditional class. Findings also indicate that high-achieving students experienced the greatest benefit from GAE activities. Some at-risk student groups (e.g., two-year transfer students showed comparably low learning gains in the course, despite the additional support that may have been afforded by active learning. Collectively, these findings provide valuable feedback that may assist other instructors who wish to revise their courses and recommendations for institutions regarding prerequisite coursework approval policies.

  12. Headspace Moisture Mapping and the Information That Can Be Gained about Freeze-Dried Materials and Processes.

    Science.gov (United States)

    Cook, Isobel A; Ward, Kevin R

    2011-01-01

    Regulatory authorities require proof that lyophilization (freeze drying) cycles have been developed logically and demonstrate uniformity. One measure of uniformity can be consistency of residual water content throughout a batch. In primary drying, heat transfer is effected by gaseous convection and conduction as well as the degree of shelf contact and evenness of heat applied; therefore residual water can be affected by container location, degree of container/tray/shelf contact, radiative heating, packing density, product formulation, and the cycle conditions themselves. In this study we have used frequency modulation spectroscopy (FMS) to create a map of headspace moisture (HSM) for 100% of vials within a number of freeze-dried batches. Karl Fischer (KF)/HSM correlations were investigated in parallel with the moisture mapping studies. A clear, linear relationship was observed between HSM and KF values for vials containing freeze-dried sucrose, implying a relatively straightforward interaction between water and the lyophilized cake for this material. Mannitol demonstrated a more complex correlation, with the interaction of different crystalline forms giving important information on the uniformity of the material produced. It was observed that annealing had a significant impact on the importance of heat transfer by conduction for vials in direct and non-direct contact with the shelf. Moisture mapping of all vials within the freeze dryer enabled further information to be obtained on the relationship of the formulation, process conditions, and equipment geometry on the intra-batch variability in HSM level. The ability of FMS to allow 100% inspection could mean that this method could play an important part in process validation and quality assurance. Lyophilization, also known as freeze drying, is a relatively old technique that has been used in its most basic form for thousands of years (e.g., preservation of fish and meat products). In its more advanced form it is

  13. Activation of materials proposed for use in superconducting linac applications

    International Nuclear Information System (INIS)

    Hanson, A.L.; Snead, C.L.; Greene, G.A.; Chan, K.C.D.; Safa, H.

    1998-01-01

    Samples of construction materials proposed for use in both superconducting and conventional high-power linear accelerators have been activated with 800 and 2,000 MeV protons to study the decay characteristics of these activated materials. Irradiation times ranged from 10 minutes to 18.67 hours. The decay characteristics of these activated materials were measured and compared to calculated decay curves based on simplified assumptions

  14. Spectral Analysis of Quantum-Dash Lasers: Effect of Inhomogeneous Broadening of the Active-Gain Region

    KAUST Repository

    Khan, Mohammed Zahed Mustafa; Ng, Tien Khee; Ooi, Boon S.; Schwingenschlö gl, Udo

    2012-01-01

    The effect of the active region inhomogeneity on the spectral characteristics of InAs/InP quantum-dash (Qdash) lasers is examined theoretically by solving the coupled set of carrier-photon rate equations. The inhomogeneity due to dash size or composition fluctuation is included in the model by considering dispersive energy states and characterized by a Gaussian envelope. In addition, the technique incorporates multilongitudinal photon modes and homogeneous broadening of the optical gain. The results predict a red shift in the central lasing wavelength of Qdash lasers on increasing the inhomogeneous broadening either explicitly or implicitly, which supports various experimental observations. The threshold current density and the lasing bandwidth are also found to increase. © 2012 IEEE.

  15. Spectral Analysis of Quantum-Dash Lasers: Effect of Inhomogeneous Broadening of the Active-Gain Region

    KAUST Repository

    Khan, Mohammed Zahed Mustafa

    2012-05-01

    The effect of the active region inhomogeneity on the spectral characteristics of InAs/InP quantum-dash (Qdash) lasers is examined theoretically by solving the coupled set of carrier-photon rate equations. The inhomogeneity due to dash size or composition fluctuation is included in the model by considering dispersive energy states and characterized by a Gaussian envelope. In addition, the technique incorporates multilongitudinal photon modes and homogeneous broadening of the optical gain. The results predict a red shift in the central lasing wavelength of Qdash lasers on increasing the inhomogeneous broadening either explicitly or implicitly, which supports various experimental observations. The threshold current density and the lasing bandwidth are also found to increase. © 2012 IEEE.

  16. Effect of diet and physical activity based interventions in pregnancy on gestational weight gain and pregnancy outcomes

    DEFF Research Database (Denmark)

    2017-01-01

    , and pre-existing medical condition; and secondarily on individual complications.Design Systematic review and meta-analysis of individual participant data (IPD). Data sources Major electronic databases from inception to February 2017 without language restrictions.Eligibility criteria for selecting studies...... Randomised trials on diet and physical activity based interventions in pregnancy.Data synthesis Statistical models accounted for clustering of participants within trials and heterogeneity across trials leading to summary mean differences or odds ratios with 95% confidence intervals for the effects overall...... intervention effects across subgroups, for either gestational weight gain or composite outcomes. There was strong evidence that interventions reduced the odds of caesarean section (0.91, 0.83 to 0.99, I2=0%; 32 studies, 11 410 women), but not for other individual complications in IPD meta-analysis. When IPD...

  17. Replacing Non-Active Video Gaming by Active Video Gaming to Prevent Excessive Weight Gain in Adolescents.

    Science.gov (United States)

    Simons, Monique; Brug, Johannes; Chinapaw, Mai J M; de Boer, Michiel; Seidell, Jaap; de Vet, Emely

    2015-01-01

    The aim of the current study was to evaluate the effects of and adherence to an active video game promotion intervention on anthropometrics, sedentary screen time and consumption of sugar-sweetened beverages and snacks among non-active video gaming adolescents who primarily were of healthy weight. We assigned 270 gaming (i.e. ≥ 2 hours/week non-active video game time) adolescents randomly to an intervention group (n = 140) (receiving active video games and encouragement to play) or a waiting-list control group (n = 130). BMI-SDS (SDS = adjusted for mean standard deviation score), waist circumference-SDS, hip circumference and sum of skinfolds were measured at baseline, at four and ten months follow-up (primary outcomes). Sedentary screen time, physical activity, consumption of sugar-sweetened beverages and snacks, and process measures (not at baseline) were assessed with self-reports at baseline, one, four and ten months follow-up. Multi-level-intention to treat-regression analyses were conducted. The control group decreased significantly more than the intervention group on BMI-SDS (β = 0.074, 95%CI: 0.008;0.14), and sum of skinfolds (β = 3.22, 95%CI: 0.27;6.17) (overall effects). The intervention group had a significantly higher decrease in self-reported non-active video game time (β = -1.76, 95%CI: -3.20;-0.32) and total sedentary screen time (Exp (β = 0.81, 95%CI: 0.74;0.88) than the control group (overall effects). The process evaluation showed that 14% of the adolescents played the Move video games every week ≥ 1 hour/week during the whole intervention period. The active video game intervention did not result in lower values on anthropometrics in a group of 'excessive' non-active video gamers (mean ~ 14 hours/week) who primarily were of healthy weight compared to a control group throughout a ten-month-period. Even some effects in the unexpected direction were found, with the control group showing lower BMI-SDS and skin folds than the intervention group

  18. Replacing Non-Active Video Gaming by Active Video Gaming to Prevent Excessive Weight Gain in Adolescents.

    Directory of Open Access Journals (Sweden)

    Monique Simons

    Full Text Available The aim of the current study was to evaluate the effects of and adherence to an active video game promotion intervention on anthropometrics, sedentary screen time and consumption of sugar-sweetened beverages and snacks among non-active video gaming adolescents who primarily were of healthy weight.We assigned 270 gaming (i.e. ≥ 2 hours/week non-active video game time adolescents randomly to an intervention group (n = 140 (receiving active video games and encouragement to play or a waiting-list control group (n = 130. BMI-SDS (SDS = adjusted for mean standard deviation score, waist circumference-SDS, hip circumference and sum of skinfolds were measured at baseline, at four and ten months follow-up (primary outcomes. Sedentary screen time, physical activity, consumption of sugar-sweetened beverages and snacks, and process measures (not at baseline were assessed with self-reports at baseline, one, four and ten months follow-up. Multi-level-intention to treat-regression analyses were conducted.The control group decreased significantly more than the intervention group on BMI-SDS (β = 0.074, 95%CI: 0.008;0.14, and sum of skinfolds (β = 3.22, 95%CI: 0.27;6.17 (overall effects. The intervention group had a significantly higher decrease in self-reported non-active video game time (β = -1.76, 95%CI: -3.20;-0.32 and total sedentary screen time (Exp (β = 0.81, 95%CI: 0.74;0.88 than the control group (overall effects. The process evaluation showed that 14% of the adolescents played the Move video games every week ≥ 1 hour/week during the whole intervention period.The active video game intervention did not result in lower values on anthropometrics in a group of 'excessive' non-active video gamers (mean ~ 14 hours/week who primarily were of healthy weight compared to a control group throughout a ten-month-period. Even some effects in the unexpected direction were found, with the control group showing lower BMI-SDS and skin folds than the intervention

  19. Replacing Non-Active Video Gaming by Active Video Gaming to Prevent Excessive Weight Gain in Adolescents

    Science.gov (United States)

    Simons, Monique; Brug, Johannes; Chinapaw, Mai J. M.; de Boer, Michiel; Seidell, Jaap; de Vet, Emely

    2015-01-01

    Objective The aim of the current study was to evaluate the effects of and adherence to an active video game promotion intervention on anthropometrics, sedentary screen time and consumption of sugar-sweetened beverages and snacks among non-active video gaming adolescents who primarily were of healthy weight. Methods We assigned 270 gaming (i.e. ≥2 hours/week non-active video game time) adolescents randomly to an intervention group (n = 140) (receiving active video games and encouragement to play) or a waiting-list control group (n = 130). BMI-SDS (SDS = adjusted for mean standard deviation score), waist circumference-SDS, hip circumference and sum of skinfolds were measured at baseline, at four and ten months follow-up (primary outcomes). Sedentary screen time, physical activity, consumption of sugar-sweetened beverages and snacks, and process measures (not at baseline) were assessed with self-reports at baseline, one, four and ten months follow-up. Multi-level-intention to treat-regression analyses were conducted. Results The control group decreased significantly more than the intervention group on BMI-SDS (β = 0.074, 95%CI: 0.008;0.14), and sum of skinfolds (β = 3.22, 95%CI: 0.27;6.17) (overall effects). The intervention group had a significantly higher decrease in self-reported non-active video game time (β = -1.76, 95%CI: -3.20;-0.32) and total sedentary screen time (Exp (β = 0.81, 95%CI: 0.74;0.88) than the control group (overall effects). The process evaluation showed that 14% of the adolescents played the Move video games every week ≥1 hour/week during the whole intervention period. Conclusions The active video game intervention did not result in lower values on anthropometrics in a group of ‘excessive’ non-active video gamers (mean ~ 14 hours/week) who primarily were of healthy weight compared to a control group throughout a ten-month-period. Even some effects in the unexpected direction were found, with the control group showing lower BMI

  20. Thermochemically active iron titanium oxide materials

    Energy Technology Data Exchange (ETDEWEB)

    Coker, Eric Nicholas; Miller, James E.

    2018-01-16

    A thermal oxidation-reduction cycle is disclosed that uses iron titanium oxide as the reactive material. The cycle may be used for the thermal splitting of water and/or carbon dioxide to form hydrogen and/or carbon monoxide. The formed compounds may be used as syngas precursors to form fuels.

  1. Antibacterial nanofiber materials activated by light

    Czech Academy of Sciences Publication Activity Database

    Jesenská, S.; Plištil, L.; Kubát, Pavel; Lang, Kamil; Brožová, Libuše; Popelka, Štěpán; Szatmáry, Lórant; Mosinger, Jiří

    99A, č. 4 (2011), s. 676-683 ISSN 1549-3296 R&D Projects: GA ČR GAP208/10/1678 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z40320502; CEZ:AV0Z40500505 Keywords : antibacterial nanofiber materials * photoactive * singlet oxygen Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.625, year: 2011

  2. Enclosure for handling high activity materials

    International Nuclear Information System (INIS)

    Jimeno de Osso, F.

    1977-01-01

    One of the most important problems that are met at the laboratories producing and handling radioisotopes is that of designing, building and operating enclosures suitable for the safe handling of active substances. With this purpose in mind, an enclosure has been designed and built for handling moderately high activities under a shielding made of 150 mm thick lead. In this report a description is given of those aspects that may be of interest to people working in this field. (Author)

  3. Enclosure for handling high activity materials abstract

    International Nuclear Information System (INIS)

    Jimeno de Osso, F.; Dominguez Rodriguez, G.; Cruz Castillo, F. de la; Rodriguez Esteban, A.

    1977-01-01

    One of the most important problems that are met at the laboratories producing and handling radioisotopes is that of designing, building and operating enclosures suitable for the safe handling of active substances. With that purpose in mind, an enclosure has been designed and built for handling moderately high activities under a shielding made of 150 mm thick lead. A description is given of those aspects that may be of interest to people working in this field. (author) [es

  4. Enclosure for handling high activity materials

    Energy Technology Data Exchange (ETDEWEB)

    Jimeno de Osso, F

    1977-07-01

    One of the most important problems that are met at the laboratories producing and handling radioisotopes is that of designing, building and operating enclosures suitable for the safe handling of active substances. With this purpose in mind, an enclosure has been designed and built for handling moderately high activities under a shielding made of 150 mm thick lead. In this report a description is given of those aspects that may be of interest to people working in this field. (Author)

  5. Characteristics of alkali activated material (geopolymer) in sulfuric acid solution

    Science.gov (United States)

    Simatupang, Partogi H.

    2017-09-01

    Alkali Activated Material (AAM) or Geopolymer is a solid material which made by mixing rich silica alumina material with alkaline activator. AAM is a well known candidate to replace cement based material. Many researches have claimed that AAM has better durability compared to cement based material in agressive environment. However, there was rare paper presented the direct comparison of material characteristics between Class F fly ash based AAM and Class C fly ash based AAM in such aggresive environment. Because of that, this paper present material characteristics of Class F fly ash based AAM and Class C fly ash based AAM if the materials were immersed in 10% sulfuric acid solution for 65 days. Material characteristics evaluated were (1) weight loss, (2) mineral of the material which evaluated by XRD (X-Ray Diffraction), (3) morphology and oxide compounds of material which evaluated by SEM/EDXA (Scanning Electron Microscopic/Energy Dispersive X-Ray Analyzer) and (4) compound bond which evaluated by FTIR (Fourier Transform Infra Red) Spectroscopy Testing. Alkali Activated Material used were Class F fly ash based AAM Mortar and Class C fly ash based AAM Mortar. The result is a quite difference of material characteristics between Class F fly ash based AAM and Class C fly ash based AAM.

  6. Hydrogen storage material, electrochemically active material, electrochemical cell and electronic equipment

    NARCIS (Netherlands)

    2008-01-01

    The invention relates to a hydrogen storage material comprising an alloy of magnesium. The invention further relates to an electrochemically active material and an electrochemical cell provided with at least one electrode comprising such a hydrogen storage material. Also, the invention relates to

  7. Gestational weight gain.

    Science.gov (United States)

    Kominiarek, Michelle A; Peaceman, Alan M

    2017-12-01

    Prenatal care providers are advised to evaluate maternal weight at each regularly scheduled prenatal visit, monitor progress toward meeting weight gain goals, and provide individualized counseling if significant deviations from a woman's goals occur. Today, nearly 50% of women exceed their weight gain goals with overweight and obese women having the highest prevalence of excessive weight gain. Risks of inadequate weight gain include low birthweight and failure to initiate breast-feeding whereas the risks of excessive weight gain include cesarean deliveries and postpartum weight retention for the mother and large-for-gestational-age infants, macrosomia, and childhood overweight or obesity for the offspring. Prenatal care providers have many resources and tools to incorporate weight and other health behavior counseling into routine prenatal practices. Because many women are motivated to improve health behaviors, pregnancy is often considered the optimal time to intervene for issues related to eating habits and physical activity to prevent excessive weight gain. Gestational weight gain is a potentially modifiable risk factor for a number of adverse maternal and neonatal outcomes and meta-analyses of randomized controlled trials report that diet or exercise interventions during pregnancy can help reduce excessive weight gain. However, health behavior interventions for gestational weight gain have not significantly improved other maternal and neonatal outcomes and have limited effectiveness in overweight and obese women. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Overview of European Community (Activity 3) work on materials properties of fast reactor structural materials

    International Nuclear Information System (INIS)

    Wood, D.S.

    The Fast Reactor Coordinating Committee set up in 1974 the Working Group Codes and Standards, and organized its work into four main activities: Manufacturing standards, Structural analysis, Materials and Classification of components. The main purpose of materials activity is to compare and contrast existing national specifications and associated properties relevant to structural materials in fast reactors. Funds are available on a yearly basis for tasks to be carried out through Study Contracts. At present about four Study Contract Reports are prepared each year

  9. Physical activity in healthy, older people. How many drops of sweat away from gain the health benefit?

    Directory of Open Access Journals (Sweden)

    Agnieszka Kujawska

    2017-07-01

    Full Text Available Introduction: Aging process leads to increased risk of functional impairments and diseases occurrence. Sedentary lifestyle is one of the main risk factors the occurrence of chronic disease such a diabetes and cardiovascular disease. On the other hand, results of many studies showed that regular physical activity (PA and physical exercise (PE could decrease the risk of these hazards. Last decades were fruitful in developing evidence-based recommendations for physical activity and exercise in older people, therefore it is worth to examine dynamics of development and the similarities between different recommendations.  Material and methods: Articles in the EBSCO database have been analyzed using keywords: older people, physical exercise, physical activity, recommendations, aerobic training, resistance training. Results: Studies showed that people who were more active during lifetime, have greater self-efficacy, better physical and mental health status and in general higher satisfaction on the autumn of their life. Every analyzed recommendation underlies the negative consequences of sedentary activity, however, there is no evidence-based “cut-off” point. Similarly, there is not clear optimal “dose” of PA or PE to prescribe for older patients. Conclusions: It seems that undertaking light level of PA activity is more beneficial than none PA or sedentary lifestyle. The newest recommendations underlie the possibility of the existence of positive linear relationship between the level of PA and health benefits: every additional amount of time spent on PA during week could be related with additional health benefit

  10. Microbial activity on ligno cellulosic material

    International Nuclear Information System (INIS)

    Abdullah, N.; Wan, H.Y.; Jalaludin, S.

    1991-01-01

    Study of rumen bacteria and fungi colonizing rice straw was conducted in situ while the ability of rumen fungi to produce polysaccharides was investigated in vitro. In the microbial colonization study by electron microscopy, it was observed that rice straw fragments were heavily colonized by bacteria and fungi after 6 h of incubation in the rumen of cattle and buffaloes. Extensive degradation of cell walls was observed, particularly with rice fragments after 24 h of incubation. The fungal isolate from the rumen of cattle when in straw showed high activity of cellobiose, CMCase and FPase and to a lesser extent, xylanase and cellulase. (author)

  11. Materials challenges for ITER - Current status and future activities

    Energy Technology Data Exchange (ETDEWEB)

    Barabash, V. [ITER International Team, Boltsmannstrasse 2, 85748 Garching (Germany)]. E-mail: valdimir.barabash@iter.org; Peacock, A. [EFDA Close Support Unit, 85748 Garching (Germany); Fabritsiev, S. [D.V. Efremov Scientific Research Institute, 196641 St. Petersburg (Russian Federation); Kalinin, G. [ENES, P.O. Box 788, 101000 Moscow (Russian Federation); Zinkle, S. [Metals and Ceramics Division, ORNL, P.O. Box 2008, Oak Ridge, TN 37831-6138 (United States); Rowcliffe, A. [Metals and Ceramics Division, ORNL, P.O. Box 2008, Oak Ridge, TN 37831-6138 (United States); Rensman, J.-W. [NRG, P.O. Box 25, 1755 ZG Petten (Netherlands); Tavassoli, A.A. [Commissariat a l' Energie Atomique, CEA/Saclay, 91191 Gif sur Yvette cedex (France); Marmy, P. [CRPP, EPFL, Association EURATOM-Confederation Suisse, 5232, Villigen PSI (Switzerland); Karditsas, P.J. [EURATOM/UKAEA Fusion Association, Abingdon, Oxon OX14 3DB (United Kingdom); Gillemot, F. [AEKI Atomic Research Institute, 1121 Budapest, (Hungary); Akiba, M. [JAEA, Naka-machi, Naka-gun, Ibaraki-ken 311-0193 (Japan)

    2007-08-01

    ITER will be the first experimental fusion facility, which brings together the key physical, material and technological issues related to development of fusion reactors. The design of ITER is complete and the construction will start soon. This paper discusses the main directions of the project oriented materials activity and main challenges related to selection of materials for the ITER components. For each application in ITER the main materials issues were identified and these issues were addressed in the dedicated ITER R and D program. The justification of materials performance was fully documented, which allows traceability and reliability of design data. Several examples are given to illustrate the main achievements and recommendations from the recently updated ITER Materials Properties Handbook. The main ongoing and future materials activities are described.

  12. Properties of Hooked Steel Fibers Reinforced Alkali Activated Material Concrete

    OpenAIRE

    Faris M. A.; Abdullah Mohd Mustafa Al Bakri; Ismail Khairul Nizar; Muniandy Ratnasamy; Mahmad Nor Aiman; Putra Jaya Ramadhansyah; Waried Wazien A. Z.

    2016-01-01

    In this study, alkali activated material was produced by using Class F fly ash from Manjung power station, Lumut, Perak, Malaysia. Fly ash then was activated by alkaline activator which is consisting of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH). Hooked end steel fibers were added into the alkali activated material system with percentage vary from 0 % – 5 %. Chemical compositions of fly ash were first analyzed by using x-ray fluorescence (XRF). All hardened alkali activated materia...

  13. Indirect flat-panel detector with avalanche gain: Fundamental feasibility investigation for SHARP-AMFPI (scintillator HARP active matrix flat panel imager)

    International Nuclear Information System (INIS)

    Zhao Wei; Li Dan; Reznik, Alla; Lui, B.J.M.; Hunt, D.C.; Rowlands, J.A.; Ohkawa, Yuji; Tanioka, Kenkichi

    2005-01-01

    An indirect flat-panel imager (FPI) with avalanche gain is being investigated for low-dose x-ray imaging. It is made by optically coupling a structured x-ray scintillator CsI(Tl) to an amorphous selenium (a-Se) avalanche photoconductor called HARP (high-gain avalanche rushing photoconductor). The final electronic image is read out using an active matrix array of thin film transistors (TFT). We call the proposed detector SHARP-AMFPI (scintillator HARP active matrix flat panel imager). The advantage of the SHARP-AMFPI is its programmable gain, which can be turned on during low dose fluoroscopy to overcome electronic noise, and turned off during high dose radiography to avoid pixel saturation. The purpose of this paper is to investigate the important design considerations for SHARP-AMFPI such as avalanche gain, which depends on both the thickness d Se and the applied electric field E Se of the HARP layer. To determine the optimal design parameter and operational conditions for HARP, we measured the E Se dependence of both avalanche gain and optical quantum efficiency of an 8 μm HARP layer. The results were used in a physical model of HARP as well as a linear cascaded model of the FPI to determine the following x-ray imaging properties in both the avalanche and nonavalanche modes as a function of E Se : (1) total gain (which is the product of avalanche gain and optical quantum efficiency); (2) linearity; (3) dynamic range; (4) gain nonuniformity resulting from thickness nonuniformity; and (5) effects of direct x-ray interaction in HARP. Our results showed that a HARP layer thickness of 8 μm can provide adequate avalanche gain and sufficient dynamic range for x-ray imaging applications to permit quantum limited operation over the range of exposures needed for radiography and fluoroscopy

  14. Reduction of impurities and activation of lithium orthosilicate breeder materials

    International Nuclear Information System (INIS)

    Knitter, Regina; Fischer, Ulrich; Herber, Stefan; Adelhelm, Christel

    2009-01-01

    The fabrication of lithium orthosilicate pebbles by melt-spraying enables a facile reprocessing of irradiated material by direct remelting. However, the necessary waiting period for the reprocessing is determined by the long-term activation of the material under irradiation that is dominated by the impurities. The activation characteristics for the current composition of lithium orthosilicate pebbles were assessed on the basis of three-dimensional activation calculations for a fusion power reactor. The calculations were used to identify critical amounts of impurities and were compared to the results of a hypothetical, pure material without impurities, as well as to a calculated Li-6 enriched OSi composition.

  15. PILLARS OF THE AUDIT ACTIVITY: MATERIALITY AND AUDIT RISK

    OpenAIRE

    ANA MARIA JOLDOŞ; IONELA CORNELIA STANCIU; GABRIELA GREJDAN

    2010-01-01

    The purpose of this article is to present the issues of materiality and audit risk within the activity of financial audit. The concepts of materiality and audit risk are described from a theoretical perspective, providing approaches found within the national and international literature and within the specific legislation. A case study on the calculation of materiality and audit risk for an entity is presented in the last part of the article. Through the theoretical approach and the case stud...

  16. Does Structured Quizzing with Process Specific Feedback Lead to Learning Gains in an Active Learning Geoscience Classroom?

    Science.gov (United States)

    Palsole, S.; Serpa, L. F.

    2013-12-01

    There is a great realization that efficient teaching in the geosciences has the potential to have far reaching effects in outreach to decision and policy makers (Herbert, 2006; Manduca & Mogk, 2006). This research in turn informs educators that the geosciences by the virtue of their highly integrative nature play an important role in serving as an entry point into STEM disciplines and helping developing a new cadre of geoscientists, scientists and a general population with an understanding of science. Keeping these goals in mind we set to design introductory geoscience courses for non-majors and majors that move away from the traditional lecture models which don't necessarily contribute well to knowledge building and retention ((Handelsman et al., 2007; Hake, 1997) to a blended active learning classroom where basic concepts and didactic information is acquired online via webquests, lecturettes and virtual field trips and the face to face portions of the class are focused on problem solving exercises. The traditional way to ensure that students are prepared for the in-class activity is to have the students take a quiz online to demonstrate basic competency. In the process of redesign, we decided to leverage the technology to build quizzes that are highly structured and map to a process (formation of divergent boundaries for example) or sets of earth processes that we needed the students to know before in-class activities. The quizzes can be taken multiple times and provide process specific feedback, thus serving as a heuristic to the students to ensure they have acquired the necessary competency. The heuristic quizzes were developed and deployed over a year with the student data driving the redesign process to ensure synchronicity. Preliminary data analysis indicates a positive correlation between higher student scores on in-class application exercises and time spent on the process quizzes. An assessment of learning gains also indicate a higher degree of self

  17. Relative contributions of energy expenditure on physical activity, body composition and weight gain to the evolution of impaired glucose tolerance to Frank diabetes

    International Nuclear Information System (INIS)

    Forrester, T.; Wilks, R.; Jahoor, F.; Adeyemo, A.

    1999-01-01

    In modem technological societies the requirement for physical work is diminished and access to food is unrestricted. Under these circumstances a large proportion of the population will gain weight and develop obesity and diabetes. At the individual level, genetic and behavioural factors must combine to lead to an imbalance between energy intake and its expenditure. Weight gain, especially rapid weight gain in a population appears to increase the risk of diabetes sharply. Thus understanding the route to weight gain and obesity, and the modulatory effects of physical activity on development of glucose intolerance is critical to credible intervention strategies to reverse or prevent diabetes in populations especially those in transitional societies. In this proposal we will examine the quantitative importance of non-resting energy expenditure (EE) in populations with rising levels of obesity and high prevalence of diabetes. (author)

  18. Neutron activation of building materials used in the reactor shield

    International Nuclear Information System (INIS)

    Hernandez, A.T.; Perez, G.; D'Alessandro, K.

    1993-01-01

    Cuban concretes and their main components (mineral aggregates and cement) were investigated through long-lived activation products induced by neutrons from a reactor. The multielemental content in the materials studied was obtained by neutron activation analysis in an IBR-2 reactor and gamma activation analysis in an MT-25 microtron from Join Institute of Nuclear Research of Dubna. After irradiation of building materials for 30 years by a neutron flow of unitary density, induced radioactivity was calculated according to experimental data. The comparative evaluation of different concretes aggregates and two types of cement related to the activation properties is discussed

  19. Soft Active Materials for Actuation, Sensing, and Electronics

    OpenAIRE

    Kramer, Rebecca Krone

    2012-01-01

    Future generations of robots, electronics, and assistive medical devices will include systems that are soft and elastically deformable, allowing them to adapt their morphology in unstructured environments. This will require soft active materials for actuation, circuitry, and sensing of deformation and contact pressure. The emerging field of soft robotics utilizes these soft active materials to mimic the inherent compliance of natural soft-bodied systems. As the elasticity of robot components ...

  20. Properties of Hooked Steel Fibers Reinforced Alkali Activated Material Concrete

    Directory of Open Access Journals (Sweden)

    Faris M. A.

    2016-01-01

    Full Text Available In this study, alkali activated material was produced by using Class F fly ash from Manjung power station, Lumut, Perak, Malaysia. Fly ash then was activated by alkaline activator which is consisting of sodium silicate (Na2SiO3 and sodium hydroxide (NaOH. Hooked end steel fibers were added into the alkali activated material system with percentage vary from 0 % – 5 %. Chemical compositions of fly ash were first analyzed by using x-ray fluorescence (XRF. All hardened alkali activated material samples were tested for density, workability, and compression after 28 days. Results show a slight increase of density with the addition of steel fibers. However, the workability was reduced with the addition of steel fibers content. Meanwhile, the addition of steel fibers shows the improvement of compressive strength which is about 19 % obtained at 3 % of steel fibers addition.

  1. Low Specific Activity materials concepts are being reevaluated

    International Nuclear Information System (INIS)

    Rawl, R.R.

    1993-01-01

    Many types of radioactive low-level waste are classified, packaged, and transported as Low-Specific Activity (LSA) material. The transportation regulations allow LSA materials to be shipped in economical packagings and, under certain conditions, waives compliance with other detailed requirements such as labeling. The fundamental concepts which support the LSA category are being thoroughly reevaluated to determine the defensibility of the provisions. A series of national and international events are leading to the development of new dose models which are likely to fundamentally change the ways these materials are defined. Similar basis changes are likely for the packaging requirements applicable to these materials

  2. Irradiation can for the activation of materials in nuclear reactors

    International Nuclear Information System (INIS)

    Schneider, B.; Findeisen, A.; Katzmann, H.

    1985-01-01

    The invention is concerning with an irradiation can for the activation of materials in nuclear reactors in particular for materials with a high heat generation due to irradiation. A good heat transfer between the irradiated material and the irradiation can environment has been guaranteed by a special can design. The outside of the can consists of a tube or a tube bandle which has been formed as a water guide tube. One or more tubes containing the irradiated materials have been positioned at the inner areas of the irradiated can

  3. Clearance potential of ITER vacuum vessel activated materials

    International Nuclear Information System (INIS)

    Cepraga, D.G.; Cambi, G.; Frisoni, M.

    2002-01-01

    To demonstrate fusion's environmental attractiveness over the entire life cycle, a waste analysis is mandatory. The clearance is recommended by IAEA for releasing activated solid materials from regulatory control and for waste management policy. The paper focuses on the approach used to support waste analyses for ITER Generic Site Safety Report. The Material Unconditional Clearance Index of all the materials/zones on the equatorial mid-plane of ITER machine have been evaluated, based on IAEA-TECDOC-855. The Bonami-Nitawl-XSDNRPM sequence of the Scale-4.4a code system (using Vitenea-J library) has been firstly used for radiation transport analyses. Then the Anita-2000 code package is used for the activation calculation. The paper presents also, as an example, an application of the clearance indexes estimation for the ITER vacuum vessel materials. The results of the Anita-2000 have been compared with those obtained using the Fispact-99 activation code. (author)

  4. Materials Science Division activity report 1991-1993

    International Nuclear Information System (INIS)

    Amarendra, G.; Tiwari, A.M.; Subramanian, N.; Venugopal Rao, G.

    1995-01-01

    This progress report gives an account of the various research and developmental activities carried out at the Materials Science Division of the Indira Gandhi Centre for Atomic Research, Kalpakkam during 1991-93. It also gives a summary of the results of the research activities, describes the experimental facilities and also list the publications

  5. Security of material: Preventing criminal activities involving nuclear and other radioactive materials

    International Nuclear Information System (INIS)

    Nilsson, A.

    2001-01-01

    The report emphasizes the need for national regulatory authorities to include in the regulatory systems, measures to control and protect nuclear materials from being used in illegal activities, as well as aspects of relevance for detecting and responding to illegal activities involving nuclear and other radioactive materials. The report will give an overview of the international treaties and agreements that underpin the establishment of a regulatory structure necessary for States to meet their non-proliferation policy and undertakings. Ongoing work to strengthen the protection of nuclear material and to detect and respond to illegal activities involving nuclear and other radioactive material will be included. The focus of the paper is on the need for standards and national regulation in the nuclear security area. (author)

  6. Transmutation and activation of fusion reactor wall and structural materials

    International Nuclear Information System (INIS)

    Jarvis, O.N.

    1979-01-01

    This report details the extent of the nuclear data needed for inclusion in a data library to be used for general assessments of fusion reactor structure activation and transmutation, describes the sources of data available, reviews the literature and explores the reliability of current calculations by providing an independent assessment of the activity inventory to be expected from five structural materials in a simple blanket design for comparison with the results of other workers. An indication of the nuclear reactions which make important contributions to the activity, transmutation and gas production rates for these structural materials is also presented. (author)

  7. Low activation structural material candidates for fusion power plants

    International Nuclear Information System (INIS)

    Forty, C.B.A.; Cook, I.

    1997-06-01

    Under the SEAL Programme of the European Long-Term Fusion Safety Programme, an assessment was performed of a number of possible blanket structural materials. These included the steels then under consideration in the European Blanket Programme, as well as materials being considered for investigation in the Advanced Materials Programme. Calculations were performed, using SEAFP methods, of the activation properties of the materials, and these were related, based on the SEAFP experience, to assessments of S and E performance. The materials investigated were the SEAFP low-activation martensitic steel (LA12TaLC); a Japanese low-activation martensitic steel (F-82H), a range of compositional variants about this steel; the vanadium-titanium-chromium alloy which was the original proposal of the ITER JCT for the ITER in-vessel components; a titanium-aluminium intermetallic (Ti-Al) which is under investigation in Japan; and silicon carbide composite (SiC). Assessed impurities were included in the compositions of these materials, and they have very important impacts on the activation properties. Lack of sufficiently detailed data on the composition of chromium alloys precluded their inclusion in the study. (UK)

  8. Processing of Building Binder Materials to Increase their Activation

    Science.gov (United States)

    Fediuk, R. S.; Garmashov, I. S.; Kuzmin, D. E.; Stoyushko, N. Yu; Gladkova, N. A.

    2018-01-01

    The paper deals modern physical methods of activation of building powder materials. During mechanical activation a composite binder active molecules cement minerals occur in the destruction of the molecular defects in the areas of packaging and breaking metastable phase decompensation intermolecular forces. The process is accompanied by a change in the kinetics of hardening of Portland cement. Activated concrete has a number of features that are used as design characteristics of structures and are due to the structure of the activated binder and its contacts with concrete aggregates. These features also have a significant impact on the nature of the destruction of concrete under load, changing the boundaries of its microcracks and durability.

  9. Bench press and push-up at comparable levels of muscle activity results in similar strength gains.

    Science.gov (United States)

    Calatayud, Joaquin; Borreani, Sebastien; Colado, Juan C; Martin, Fernando; Tella, Victor; Andersen, Lars L

    2015-01-01

    Electromyography (EMG) exercise evaluation is commonly used to measure the intensity of muscle contraction. Although researchers assume that biomechanically comparable resistance exercises with similar high EMG levels will produce similar strength gains over the long term, no studies have actually corroborated this hypothesis. This study evaluated EMG levels during 6 repetition maximum (6RM) bench press and push-up, and subsequently performed a 5-week training period where subjects were randomly divided into 3 groups (i.e., 6RM bench press group, 6RM elastic band push-up group, or control group) to evaluate muscle strength gains. Thirty university students with advanced resistance training experience participated in the 2-part study. During the training period, exercises were performed using the same loads and variables that were used during the EMG data collection. At baseline, EMG amplitude showed no significant difference between 6RM bench press and band push-up. Significant differences among the groups were found for percent change (Δ) between pretest and posttest for 6RM (p = 0.017) and for 1 repetition maximum (1RM) (p bench press group and 6RM elastic band push-up group improved their 1RM and 6RM (Δ ranging from 13.65 to 22.21) tests significantly with similar gains, whereas control group remains unchanged. Thus, when the EMG values are comparable and the same conditions are reproduced, the aforementioned exercises can provide similar muscle strength gains.

  10. Utilization of Mineral Wools as Alkali-Activated Material Precursor

    Directory of Open Access Journals (Sweden)

    Juho Yliniemi

    2016-04-01

    Full Text Available Mineral wools are the most common insulation materials in buildings worldwide. However, mineral wool waste is often considered unrecyclable because of its fibrous nature and low density. In this paper, rock wool (RW and glass wool (GW were studied as alkali-activated material precursors without any additional co-binders. Both mineral wools were pulverized by a vibratory disc mill in order to remove the fibrous nature of the material. The pulverized mineral wools were then alkali-activated with a sodium aluminate solution. Compressive strengths of up to 30.0 MPa and 48.7 MPa were measured for RW and GW, respectively, with high flexural strengths measured for both (20.1 MPa for RW and 13.2 MPa for GW. The resulting alkali-activated matrix was a composite-type in which partly-dissolved fibers were dispersed. In addition to the amorphous material, sodium aluminate silicate hydroxide hydrate and magnesium aluminum hydroxide carbonate phases were identified in the alkali-activated RW samples. The only crystalline phase in the GW samples was sodium aluminum silicate. The results of this study show that mineral wool is a very promising raw material for alkali activation.

  11. Soft Active Materials for Actuation, Sensing, and Electronics

    Science.gov (United States)

    Kramer, Rebecca Krone

    Future generations of robots, electronics, and assistive medical devices will include systems that are soft and elastically deformable, allowing them to adapt their morphology in unstructured environments. This will require soft active materials for actuation, circuitry, and sensing of deformation and contact pressure. The emerging field of soft robotics utilizes these soft active materials to mimic the inherent compliance of natural soft-bodied systems. As the elasticity of robot components increases, the challenges for functionality revert to basic questions of fabrication, materials, and design - whereas such aspects are far more developed for traditional rigid-bodied systems. This thesis will highlight preliminary materials and designs that address the need for soft actuators and sensors, as well as emerging fabrication techniques for manufacturing stretchable circuits and devices based on liquid-embedded elastomers.

  12. System to detect nuclear materials by active neutron method

    International Nuclear Information System (INIS)

    Koroev, M.; Korolev, Yu.; Lopatin, Yu.; Filonov, V.

    1999-01-01

    The report presents the results of the development of the system to detect nuclear materials by active neutron method measuring delayed neutrons. As the neutron source the neutron generator was used. The neutron generator was controlled by the system. The detectors were developed on the base of the helium-3 counters. Each detector consist of 6 counters. Using a number of such detectors it is possible to verify materials stored in different geometry. There is an spectrometric scintillator detector in the system which gives an additional functional ability to the system. The system could be used to estimate the nuclear materials in waste, to detect the unauthorized transfer of the nuclear materials, to estimate the material in tubes [ru

  13. Long-lived activation products in reactor materials

    International Nuclear Information System (INIS)

    Evans, J.C.; Lepel, E.L.; Sanders, R.W.; Wilkerson, C.L.; Silker, W.; Thomas, C.W.; Abel, K.H.; Robertson, D.R.

    1984-08-01

    The purpose of this program was to assess the problems posed to reactor decommissioning by long-lived activation products in reactor construction materials. Samples of stainless steel, vessel steel, concrete, and concrete ingredients were analyzed for up to 52 elements in order to develop a data base of activatable major, minor, and trace elements. Large compositional variations were noted for some elements. Cobalt and niobium concentrations in stainless steel, for example, were found to vary by more than an order of magnitude. A thorough evaluation was made of all possible nuclear reactions that could lead to long lived activation products. It was concluded that all major activation products have been satisfactorily accounted for in decommissioning planning studies completed to date. A detailed series of calculations was carried out using average values of the measured compositions of the appropriate materials to predict the levels of activation products expected in reactor internals, vessel walls, and bioshield materials for PWR and BWR geometries. A comparison is made between calculated activation levels and regulatory guidelines for shallow land disposal according to 10 CFR 61. This analysis shows that PWR and BWR shroud material exceeds the Class C limits and is, therefore, generally unsuitable for near-surface disposal. The PWR core barrel material approaches the Class C limits. Most of the remaining massive components qualify as either Class A or B waste with the bioshield clearly Class A, even at the highest point of activation. Selected samples of activated steel and concrete were subjected to a limited radiochemical analysis program as a verification of the computer model. Reasonably good agreement with the calculations was obtained where comparison was possible. In particular, the presence of 94 Nb in activated stainless steel at or somewhat above expected levels was confirmed

  14. Quality of Standard Reference Materials for Short Time Activation Analysis

    International Nuclear Information System (INIS)

    Ismail, S.S.; Oberleitner, W.

    2003-01-01

    Some environmental reference materials (CFA-1633 b, IAEA-SL-1, SARM-1,BCR-176, Coal-1635, IAEA-SL-3, BCR-146, and SRAM-5) were analysed by short-time activation analysis. The results show that these materials can be classified in three groups, according to their activities after irradiation. The obtained results were compared in order to create a quality index for determination of short-lived nuclides at high count rates. It was found that Cfta is not a suitable standard for determining very short-lived nuclides (half-lives<1 min) because the activity it produces is 15-fold higher than that SL-3. Biological reference materials, such as SRM-1571, SRM-1573, SRM-1575, SRM-1577, IAEA-392, and IAEA-393, were also investigated by a higher counting efficiency system. The quality of this system and its well-type detector for investigating short-lived nuclides was discussed

  15. Determination of ancient ceramics reference material by neutron activation analysis

    International Nuclear Information System (INIS)

    Li Huhou; Sun Jingxin; Wang Yuqi; Lu Liangcai

    1986-01-01

    Contents of trace elements in the reference material of ancient ceramics (KPS-1) were determined by means of activation analysis, using thermal neutron irradiation produced in nuclear reactor. KPS-1 favoured the analysis of ancient ceramics because it had not only many kinds of element but also appropriate contents of composition. The values presented here are reliable within the experimental precision, and have shown that the reference material had a good homogeneity. So KPS-1 can be used as a suitable reference material for the ancient ceramics analysis

  16. PILLARS OF THE AUDIT ACTIVITY: MATERIALITY AND AUDIT RISK

    Directory of Open Access Journals (Sweden)

    ANA MARIA JOLDOŞ

    2010-01-01

    Full Text Available The purpose of this article is to present the issues of materiality andaudit risk within the activity of financial audit. The concepts of materiality and audit risk aredescribed from a theoretical perspective, providing approaches found within the national andinternational literature and within the specific legislation. A case study on the calculation ofmateriality and audit risk for an entity is presented in the last part of the article. Through thetheoretical approach and the case study, it was concluded that materiality has an importantrole in determining the type of report to be issued, that is why it can be considered helpful forthose involved in the audit process.

  17. Clearance, recycling and disposal of fusion activated material

    International Nuclear Information System (INIS)

    Zucchetti, M.; Forrest, R.; Forty, C.; Gulden, W.; Rocco, P.; Rosanvallon, S.

    2001-01-01

    The SEAFP-99 waste management studies include further explorations in the direction of activated materials management, adopting a more realistic approach in order to consolidate and refine the previous encouraging findings of SEAFP waste management studies performed till 1998. The main results were obtained in the following topics, impact of materials/components optimisation on waste management issues; integrated approach to recycling and clearance; analysis of the potential for fusion specific repositories and hazard-relevant nuclides/processes; materials detritiation. The overall conclusion is that the adoption of a more realistic approach for the analysis has been beneficial. The results further confirmed the potential for waste minimisation and hazard reduction

  18. Weight gain in women who practice moderate physical activity during pregnancy and its influence on the total duration of labor: a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Raquel Rodriguez-Blanque

    2017-07-01

    Full Text Available Introduction: At present, OMS establishes that sedentarism and poor eating habits are two major problems of industrialized society, which cause high rates of overweight and obesity in the population. This fact also extends to women of reproductive age, which causes an excessive gain of weight during pregnancy, which can be a risk for the baby and for the mother. Objective: To know the benefits of moderate aquatic physical activity and its influence on the total duration of labor, according to the body mass index (BMI of pregnant women. Material and methods: Randomized clinical trial of 140 healthy pregnant women, ages between 21 and 43 years. A simple random sampling was used, the sample being conformed into two groups; Intervention (IG; n = 70 and Control (CG; n = 70. Each group was categorized according to the BMI, according to the OMS international classification. The recruitment was at 12 weeks of gestation in the ultrasound control of the first trimester, in the different obstetrical services of Granada. The program began at week 20 of gestation and ended at week 37. The perinatal results were obtained from the Labor Diagram of each woman, recorded in the Labor Ward Services of the University Hospital Complex of Granada. Results: The mean weight gain during pregnancy in the CG was 2.89 kg more compared to the IG. Significant differences were obtained in the total time of labor in the categories of BMI, Normopesus and Overweight. The Obesity variable shows that the results were not positive enough to reveal a statistical significance, although a difference of 531.89 min was recorded in the CG versus 374.14 min for the IG. This represents a difference of 2.63 hours on average, data that is clinically significant. Conclusion: Non-obese pregnant women, who have followed the SWEP method, present a statistically significant decrease in total delivery times between groups. However, in obese women there is a decrease in the total time of delivery

  19. Nondestructive neutron activation analysis of mineral materials. III

    International Nuclear Information System (INIS)

    Randa, Z.; Benada, J.; Kuncir, J.; Vobecky, M.

    1979-01-01

    A description is presented of sampling, calibration standards, the method of activation and measurement, activation product identification, the respective nuclear reactions, interfering admixtures, and pre-activation operations. The analysis is described of sulphides, halogenides, oxides, sulphates, carbonates, phosphates, silicates, aluminosilicates, composite minerals containing lanthanides, rocks, tektites, meteors, and plant materials. The method allows determining mainly F, Mg, Al, Ti, V, Nb, Rh, and I which cannot be determined by long-term activation (LTA). It is more sensitive than LTA in determining Ca, Cu, In, and Dy. The analysis takes less time, irradiation and measurement are less costly. The main mineral components are quickly found. (M.K.)

  20. Active materials for automotive adaptive forward lighting Part 1: system requirements vs. material properties

    Science.gov (United States)

    Keefe, Andrew C.; Browne, Alan L.; Johnson, Nancy L.

    2011-04-01

    Adaptive Frontlighting Systems (AFS in GM usage) improve visibility by automatically optimizing the beam pattern to accommodate road, driving and environmental conditions. By moving, modifying, and/or adding light during nighttime, inclement weather, or in sharp turns, the driver is presented with dynamic illumination not possible with static lighting systems The objective of this GM-HRL collaborative research project was to assess the potential of active materials to decrease the cost, mass, and packaging volume of current electric stepper-motor AFS designs. Solid-state active material actuators, if proved suitable for this application, could be less expensive than electric motors and have lower part count, reduced size and weight, and lower acoustic and EMF noise1. This paper documents Part 1 of the collaborative study, assessing technically mature, commercially available active materials for use as actuators. Candidate materials should reduce cost and improve AFS capabilities, such as increased angular velocity on swivel. Additional benefits to AFS resulting from active materials actuators were to be identified as well such as lower part count. In addition, several notional approaches to AFS were documented to illustrate the potential function, which is developed more fully in Part 2. Part 1 was successful in verifying the feasibility of using two active materials for AFS: shape memory alloys, and piezoelectrics. In particular, this demonstration showed that all application requirements including those on actuation speed, force, and cyclic stability to effect manipulation of the filament assembly and/or the reflector could be met by piezoelectrics (as ultrasonic motors) and SMA wire actuators.

  1. Active and Passive Diagnostic Signatures of Special Nuclear Materials

    Energy Technology Data Exchange (ETDEWEB)

    Myers, William L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Myers, Steven Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-26

    An overview will be given discussing signatures associated with special nuclear materials acquired using both active and passive diagnostic techniques. Examples of how technology advancements have helped improve diagnostic capabilities to meet the challenges of today’s applications will be discussed.

  2. Smart Materials and Active Noise and Vibration Control in Vehicles

    NARCIS (Netherlands)

    Doppenberg, E.J.J.; Berkhoff, Arthur P.; van Overbeek, M.; Gissinger, G.L.

    2001-01-01

    The paper presents the results for the reduction of sound radiated from a structure using different control methodologies, and discusses two approaches for active structural acoustic control: the acoustic approach or the vibro-acoustic approach. Integrated actuators in structure material are

  3. Numerical Modeling of Multi-Material Active Magnetic Regeneration

    DEFF Research Database (Denmark)

    Nielsen, Kaspar Kirstein; Engelbrecht, Kurt; Bahl, Christian Robert Haffenden

    2009-01-01

    and the specific heat as a function of temperature at constant magnetic field. A 2.5-dimensional numerical model of an active magnetic regenerative (AMR) refrigerator device is presented. The experimental AMR located at Risø DTU has been equipped with a parallel-plate based regenerator made of the two materials...

  4. Active neutron technique for detecting attempted special nuclear material diversion

    International Nuclear Information System (INIS)

    Smith, G.W.; Rice, L.G. III.

    1979-01-01

    The identification of special nuclear material (SNM) diversion is necessary if SNM inventory control is to be maintained at nuclear facilities. (Special nuclear materials are defined for this purpose as either 235 U of 239 Pu.) Direct SNM identification by the detection of natural decay or fission radiation is inadequate if the SNM is concealed by appropriate shielding. The active neutron interrogation technique described combines direct SNM identification by delayed fission neutron (DFN) detection with implied SNM detection by the identification of materials capable of shielding SNM from direct detection. This technique is being developed for application in an unattended material/equipment portal through which items such as electronic instruments, packages, tool boxes, etc., will pass. The volume of this portal will be 41-cm wide, 53-cm high and 76-cm deep. The objective of this technique is to identify an attempted diversion of at least 20 grams of SNM with a measurement time of 30 seconds

  5. Redox-active Hybrid Materials for Pseudocapacitive Energy Storage

    Science.gov (United States)

    Boota, Muhammad

    Organic-inorganic hybrid materials show a great promise for the purpose of manufacturing high performance electrode materials for electrochemical energy storage systems and beyond. Molecular level combination of two best suited components in a hybrid material leads to new or sometimes exceptional sets of physical, chemical, mechanical and electrochemical properties that makes them attractive for broad ranges of applications. Recently, there has been growing interest in producing redox-active hybrid nanomaterials for energy storage applications where generally the organic component provides high redox capacitance and the inorganic component offers high conductivity and robust support. While organic-inorganic hybrid materials offer tremendous opportunities for electrochemical energy storage applications, the task of matching the right organic material out of hundreds of natural and nearly unlimited synthetic organic molecules to appropriate nanostructured inorganic support hampers their electrochemical energy storage applications. We aim to present the recent development of redox-active hybrid materials for pseudocapacitive energy storage. We will show the impact of combination of suitable organic materials with distinct carbon nanostructures and/or highly conductive metal carbides (MXenes) on conductivity, charge storage performance, and cyclability. Combined experimental and molecular simulation results will be discussed to shed light on the interfacial organic-inorganic interactions, pseudocapacitive charge storage mechanisms, and likely orientations of organic molecules on conductive supports. Later, the concept of all-pseudocapacitive organic-inorganic asymmetric supercapacitors will be highlighted which open up new avenues for developing inexpensive, sustainable, and high energy density aqueous supercapacitors. Lastly, future challenges and opportunities to further tailor the redox-active hybrids will be highlighted.

  6. Transport of biologically active material in laser cutting.

    Science.gov (United States)

    Frenz, M; Mathezloic, F; Stoffel, M H; Zweig, A D; Romano, V; Weber, H P

    1988-01-01

    The transport of biologically active material during laser cutting with CO2 and Er lasers is demonstrated. This transport mechanism removes particles from the surface of gelatin, agar, and liver samples into the depth of the laser-formed craters. The transport phenomenon is explained by a contraction and condensation of enclosed hot water vapor. We show by cultivating transported bacteria in agar that biological particles can survive the shock of the transport. Determination of the numbers of active cells evidences a more pronounced activity of the cultivated bacteria after impact with an Er laser than with a CO2 laser.

  7. Activation of a Ca-bentonite as buffer material

    Science.gov (United States)

    Huang, Wei-Hsing; Chen, Wen-Chuan

    2016-04-01

    Swelling behavior is an important criterion in achieving the low-permeability sealing function of buffer material. A potential buffer material may be used for radioactive waste repository in Taiwan is a locally available clayey material known as Zhisin clay, which has been identified as a Ca-bentonite. Due to its Ca-based origin, Zhisin was found to exhibit swelling capacity much lower than that of Na-bentonite. To enhance the swelling potential of Zhisin clay, a cation exchange process by addition of Na2CO3 powder was introduced in this paper. The addition of Na2CO3 reagent to Zhisin clay, in a liquid phase, caused the precipitation of CaCO3 and thereby induced a replacement of Ca2+ ions by Na+ ions on the surface of bentonite. Characterization test conducted on Zhisin clay includes chemical analysis, cation exchange capacity, X-ray diffraction, and thermogravimetry (TG). Free-swelling test apparatus was developed according to International Society of Rock Mechanics recommendations. A series of free-swelling tests were conducted on untreated and activated specimens to characterize the effect of activation on the swelling capacity of Zhisin clay. Efforts were made to determine an optimum dosage for the activation, and to evaluate the aging effect. Also, the activated material was evaluated for its stability in various hydrothermal conditions for potential applications as buffer material in a repository. Experimental results show that Na2CO3-activated Zhisin clay is superior in swelling potential to untreated Zhisin clay. Also, there exists an optimum amount of activator in terms of improvements in the swelling capacity. A distinct time-swell relationship was discovered for activated Zhisin clay. The corresponding mechanism refers to exchange of cations and breakdown of quasi-crystal, which results in ion exchange hysteresis of Ca-bentonite. Due to the ion exchange hysteresis, activated bentonite shows a post-rise time-swell relationship different than the sigmoid

  8. High-Performance 1.55-µm Superluminescent Diode Based on Broad Gain InAs/InGaAlAs/InP Quantum Dash Active Region

    KAUST Repository

    Khan, Mohammed Zahed Mustafa

    2014-08-01

    We report on the high-performance characteristics from superluminescent diodes (SLDs) based on four-stack InAs/InGaAlAs chirped-barrier thickness quantum dash (Qdash) in a well structure. The active region exhibits a measured broad gain spectrum of 140 nm, with a peak modal gain of ~41 cm-1. The noncoated two-section gainabsorber broad-area and ridge-waveguide device configuration exhibits an output power of > 20 mW and > 12 mW, respectively. The corresponding -3-dB bandwidths span ~82 nm and ~72 nm, with a small spectral ripple of <; 0.2 dB, related largely to the contribution from dispersive height dash ensembles of the highly inhomogeneous active region. These C-L communication band devices will find applications in various cross-disciplinary fields of optical metrology, optical coherent tomography, etc.

  9. Present status of low activation materials R and D for fusion

    International Nuclear Information System (INIS)

    Kohyama, Akira

    1999-01-01

    Low activation materials development is one of the key technologies for fusion engineering. Starting with a brief introduction about design concepts of low activation materials for fusion, current activities on the major three low activation material categories, such as low activation ferritic steels, vanadium alloys and SiC/SiC composite materials, are provided. Material database improvement in low-activation ferritic steel R and D and material property improvements in SiC/SiC are emphasized. (author)

  10. Activation of accelerator construction materials by heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Katrík, P., E-mail: p.katrik@gsi.de [GSI Darmstadt, Planckstrasse 1, D-64291 (Germany); Mustafin, E. [GSI Darmstadt, Planckstrasse 1, D-64291 (Germany); Hoffmann, D.H.H. [TU Darmstadt, Schlossgartenstraße 9, D-64289 (Germany); Pavlovič, M. [FEI STU Bratislava, Ilkovičova 3, SK-81219 (Slovakia); Strašík, I. [GSI Darmstadt, Planckstrasse 1, D-64291 (Germany)

    2015-12-15

    Activation data for an aluminum target irradiated by 200 MeV/u {sup 238}U ion beam are presented in the paper. The target was irradiated in the stacked-foil geometry and analyzed using gamma-ray spectroscopy. The purpose of the experiment was to study the role of primary particles, projectile fragments, and target fragments in the activation process using the depth profiling of residual activity. The study brought information on which particles contribute dominantly to the target activation. The experimental data were compared with the Monte Carlo simulations by the FLUKA 2011.2c.0 code. This study is a part of a research program devoted to activation of accelerator construction materials by high-energy (⩾200 MeV/u) heavy ions at GSI Darmstadt. The experimental data are needed to validate the computer codes used for simulation of interaction of swift heavy ions with matter.

  11. Goals, challenges, and successes of managing fusion activated materials

    International Nuclear Information System (INIS)

    El-Guebaly, L.; Massaut, V.; Zucchetti, M.; Tobita, K.; Cadwallader, L.

    2007-01-01

    After decades of designing magnetic and inertial fusion power plants, it is timely to develop a new framework for managing the activated materials generated during plant operation and after decommissioning - a framework that takes into account the lessons learned from numerous international fusion and fission studies and the environmental, political, and present reality in the U.S., EU, and Japan. Since the inception of the fusion projects in the early 1970s, the majority of power plant designs have focused on the disposal of active materials in geological repositories as the main option for handling the replaceable and life-of-plant components, adopting the preferred fission waste management approach. It is becoming evident that future regulations for geological burial will be upgraded to assure tighter environmental controls. Along with the political difficulty of constructing new repositories worldwide, the current reality suggests reshaping all aspects of handling the continual stream of fusion active materials. There is a growing international effort in support of this new trend. Beginning in the mid 1990s and continuing to the present, fusion designs developed in Europe, U.S., and Japan have examined replacing the disposal option with more environmentally attractive approaches, redirecting their attention to recycling and clearance while continuing the development of materials with low activation potential. These options became more technically feasible in recent years with the development of radiation-hardened remote handling (RH) tools and the introduction of the clearance category for slightly radioactive materials by national and international nuclear agencies. We applied all scenarios to selected fusion studies. While recycling and clearance appeared technically attractive and judged, in some cases, a must requirement to control the radwaste stream, the disposal scheme emerged as the preferred option for specific components for several reasons, including

  12. Prompt gamma cold neutron activation analysis applied to biological materials

    International Nuclear Information System (INIS)

    Rossbach, M.; Hiep, N.T.

    1992-01-01

    Cold neutrons at the external neutron guide laboratory (ELLA) of the KFA Juelich are used to demonstrate their profitable application for multielement characterization of biological materials. The set-up and experimental conditions of the Prompt Gamma Cold Neutron Activation Analysis (PGCNAA) device is described in detail. Results for C, H, N, S, K, B, and Cd using synthetic standards and the 'ratio' technique for calculation are reported for several reference materials and prove the method to be reliable and complementary with respect to the elements being determined by INAA. (orig.)

  13. Biological and environmental reference materials in neutron activation analysis work

    International Nuclear Information System (INIS)

    Guinn, V.P.; Gavrilas, M.

    1990-01-01

    The great usefulness of reference materials, especially ones of certified elemental composition, is discussed with particular attention devoted to their use in instrumental neutron activation analysis (INAA) work. Their use, including both certified and uncertified values, in calculations made by the INAA Advance Prediction Computer Program (APCP) is discussed. The main features of the APCP are described, and mention is made of the large number of reference materials run on the APCP (including the new personal computer version of the program), with NBS Oyster Tissue SRM-1566 used as the principal examle. (orig.)

  14. Certification of biological reference materials by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Lanjewar, Mamata R.; Lanjewar, R.B.

    2014-01-01

    A multielemental instrumental neutron activation analysis (INAA) method by short and long irradiation has been employed for the determination of 21 minor and trace elements in two standard Reference Materials P-RBF and P-WBF from Institute of Radioecology and Applied Nuclear Techniques ,Czechoslovakia. Also some biological standards such as Bowen's kale, cabbage leaves (Poland) including wheat and rice flour samples of local origin were analysed. It is suggested that INAA is an ideal method for the certification of Reference Materials of Biological Matrices. (author)

  15. Cerium-activated lanthanum beryllate as a gamma detector material

    International Nuclear Information System (INIS)

    Czirr, J.B.; Berrondo, M.

    1994-01-01

    The authors have tested a single crystal of Ce-activated lanthanum beryllate BEL(Ce) as a potential gamma detector material. The density (6.1 g.cm -3 ) and decay time (50 ns) are competitive with other recently developed materials. The scintillation efficiency is 57 to 95% that of BGO. For an excitation wavelength of 340 nm, the emission spectra is a broad peak centered at 450 mn. The H 2 annealed sample is transparent for wavelengths greater than 400 mn. They are continuing a program to improve the scintillation efficiency by varying the crystal growth conditions

  16. Gain- and Loss-Related Brain Activation Are Associated with Information Search Differences in Risky Gambles: An fMRI and Eye-Tracking Study.

    Science.gov (United States)

    Häusler, Alexander Niklas; Oroz Artigas, Sergio; Trautner, Peter; Weber, Bernd

    2016-01-01

    People differ in the way they approach and handle choices with unsure outcomes. In this study, we demonstrate that individual differences in the neural processing of gains and losses relates to attentional differences in the way individuals search for information in gambles. Fifty subjects participated in two independent experiments. Participants first completed an fMRI experiment involving financial gains and losses. Subsequently, they performed an eye-tracking experiment on binary choices between risky gambles, each displaying monetary outcomes and their respective probabilities. We find that individual differences in gain and loss processing relate to attention distribution. Individuals with a stronger reaction to gains in the ventromedial prefrontal cortex paid more attention to monetary amounts, while a stronger reaction in the ventral striatum to losses was correlated with an increased attention to probabilities. Reaction in the posterior cingulate cortex to losses was also found to correlate with an increased attention to probabilities. Our data show that individual differences in brain activity and differences in information search processes are closely linked.

  17. GAIN Technology Workshops Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Braase, Lori Ann [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-08-01

    National and global demand for nuclear energy is increasing and United States (U.S.) global leadership is eroding. There is a sense of urgency with respect to the deployment of the innovative nuclear energy technologies. The Gateway for Accelerated Innovation in Nuclear (GAIN) initiative is based on the simultaneous achievement of three strategic goals. The first is maintaining global technology leadership within the U.S. Department of Energy (DOE). The second is enabling global industrial leadership for nuclear vendors and suppliers. The third is focused on utility optimization of nuclear energy within the clean energy portfolio. An effective public-private partnership is required to achieve these goals. DOEs recognizes the recent sense of urgency new developers and investors have in getting their concepts to market. They know that time to market for nuclear technology takes too long and the facilities needed to conduct the necessary research, development and demonstration (RD&D) activities are very expensive to develop and maintain. Early technologies, in the lower technology readiness levels (TRL) need materials testing, analysis, modeling, code development, etc., most of which currently exists in the DOE national laboratory system. However, mature technologies typically need large component testing and demonstration facilities, which are expensive and long-lead efforts. By understanding the needs of advanced nuclear technology developers, GAIN will connect DOE national laboratory capabilities (e.g., facilities, expertise, materials, and data) with industry RD&D needs. In addition, GAIN is working with the Nuclear Regulatory Commission (NRC) to streamline processes and increase understanding of the licensing requirements for advanced reactors.

  18. GAIN Technology Workshops Summary Report

    International Nuclear Information System (INIS)

    Braase, Lori Ann

    2016-01-01

    National and global demand for nuclear energy is increasing and United States (U.S.) global leadership is eroding. There is a sense of urgency with respect to the deployment of the innovative nuclear energy technologies. The Gateway for Accelerated Innovation in Nuclear (GAIN) initiative is based on the simultaneous achievement of three strategic goals. The first is maintaining global technology leadership within the U.S. Department of Energy (DOE). The second is enabling global industrial leadership for nuclear vendors and suppliers. The third is focused on utility optimization of nuclear energy within the clean energy portfolio. An effective public-private partnership is required to achieve these goals. DOEs recognizes the recent sense of urgency new developers and investors have in getting their concepts to market. They know that time to market for nuclear technology takes too long and the facilities needed to conduct the necessary research, development and demonstration (RD&D) activities are very expensive to develop and maintain. Early technologies, in the lower technology readiness levels (TRL) need materials testing, analysis, modeling, code development, etc., most of which currently exists in the DOE national laboratory system. However, mature technologies typically need large component testing and demonstration facilities, which are expensive and long-lead efforts. By understanding the needs of advanced nuclear technology developers, GAIN will connect DOE national laboratory capabilities (e.g., facilities, expertise, materials, and data) with industry RD&D needs. In addition, GAIN is working with the Nuclear Regulatory Commission (NRC) to streamline processes and increase understanding of the licensing requirements for advanced reactors.

  19. Development of materials of low activation for nuclear fusion

    International Nuclear Information System (INIS)

    Kamata, Koji

    1986-01-01

    Unlike nuclear fission, in nuclear fusion, it is a feature that activated products are not formed, but this merit is to be lost if the structural materials of the equipment are activated by generated neutrons. Accordingly, the elements which are activated by neutrons must be excluded from the structural materials in nuclear fusion reactors and fusion experiment apparatuses. As the result of evaluating the materials for low induced activation, aluminum alloys are the most promising. Aluminum alloys have also excellent properties in gas release, the thermal stress of first walls due to the temperature distribution, vaporizing quantity at the time of disruption and so on. However, in the existing aluminum alloys, the lowering of strength above 150 deg C is remarkable, and when the aluminum walls of vacuum vessels are too thick, the rate of tritium breeding may lower. The Institute of Plasma Physics, Nagoya University, carried out the total design of a tokamak made of an aluminum alloy for the first time in the world. In this paper, the properties of the aluminum alloy and the feasibility of its industrial manufacture are described, and the course of improving this alloy is pointed out. Improved 5083 alloy and Al-4 % Mg-1 % Li alloy were investigated. The industrial manufacture of large plates with this Al-Mg-Li alloy is possible now. (Kako, I.)

  20. Porous Materials from Thermally Activated Kaolinite: Preparation, Characterization and Application

    Directory of Open Access Journals (Sweden)

    Jun Luo

    2017-06-01

    Full Text Available In the present study, porous alumina/silica materials were prepared by selective leaching of silicon/aluminum constituents from thermal-activated kaolinite in inorganic acid or alkali liquor. The correlations between the characteristics of the prepared porous materials and the dissolution properties of activated kaolinite were also investigated. The results show that the specific surface area (SSA of porous alumina/silica increases with silica/alumina dissolution, but without marked change of the BJH pore size. Furthermore, change in pore volume is more dependent on activation temperature. The porous alumina and silica obtained from alkali leaching of kaolinite activated at 1150 °C for 15 min and acid leaching of kaolinite activated at 850 °C for 15 min are mesoporous, with SSAs, BJH pore sizes and pore volumes of 55.8 m2/g and 280.3 m2/g, 6.06 nm and 3.06 nm, 0.1455 mL/g and 0.1945 mL/g, respectively. According to the adsorption tests, porous alumina has superior adsorption capacities for Cu2+, Pb2+ and Cd2+ compared with porous silica and activated carbon. The maximum capacities of porous alumina for Cu2+, Pb2+ and Cd2+ are 134 mg/g, 183 mg/g and 195 mg/g, respectively, at 30 °C.

  1. Evaluation and development of advanced nuclear materials: IAEA activities

    International Nuclear Information System (INIS)

    Inozemtsev, V.; Basak, U.; Killeen, J.; Dyck, G.; Zeman, A.; )

    2011-01-01

    Economical, environmental and non-proliferation issues associated with sustainable development of nuclear power bring about a need for optimization of fuel cycles and implementation of advanced nuclear systems. While a number of physical and design concepts are available for innovative reactors, the absence of reliable materials able to sustain new challenging irradiation conditions represents the real bottle-neck for practical implementation of these promising ideas. Materials performance and integrity are key issues for the safety and competitiveness of future nuclear installations being developed for sustainable nuclear energy production incorporating fuel recycling and waste transmutation systems. These systems will feature high thermal operational efficiency, improved utilization of resources (both fissile and fertile materials) and reduced production of nuclear waste. They will require development, qualification and deployment of new and advanced fuel and structural materials with improved mechanical and chemical properties combined with high radiation and corrosion resistance. The extensive, diverse, and expensive efforts toward the development of these materials can be more effectively organized within international collaborative programmes with wide participation of research, design and engineering communities. IAEA carries out a number of international projects supporting interested Member States with the use of available IAEA program implementation tools (Coordinated Research Projects, Technical Meetings, Expert Reviews, etc). The presentation summarizes the activities targeting material developments for advanced nuclear systems, with particular emphasis on fast reactors, which are the focal topics of IAEA Coordinated Research Projects 'Accelerator Simulation and Theoretical Modelling of Radiation Effects' (on-going), 'Benchmarking of Structural Materials Pre-Selected for Advanced Nuclear Reactors', 'Examination of advanced fast reactor fuel and core

  2. Active video games as a tool to prevent excessive weight gain in adolescents: rationale, design and methods of a randomized controlled trial

    Science.gov (United States)

    2014-01-01

    Background Excessive body weight, low physical activity and excessive sedentary time in youth are major public health concerns. A new generation of video games, the ones that require physical activity to play the games –i.e. active games- may be a promising alternative to traditional non-active games to promote physical activity and reduce sedentary behaviors in youth. The aim of this manuscript is to describe the design of a study evaluating the effects of a family oriented active game intervention, incorporating several motivational elements, on anthropometrics and health behaviors in adolescents. Methods/Design The study is a randomized controlled trial (RCT), with non-active gaming adolescents aged 12 – 16 years old randomly allocated to a ten month intervention (receiving active games, as well as an encouragement to play) or a waiting-list control group (receiving active games after the intervention period). Primary outcomes are adolescents’ measured BMI-SDS (SDS = adjusted for mean standard deviation score), waist circumference-SDS, hip circumference and sum of skinfolds. Secondary outcomes are adolescents’ self-reported time spent playing active and non-active games, other sedentary activities and consumption of sugar-sweetened beverages. In addition, a process evaluation is conducted, assessing the sustainability of the active games, enjoyment, perceived competence, perceived barriers for active game play, game context, injuries from active game play, activity replacement and intention to continue playing the active games. Discussion This is the first adequately powered RCT including normal weight adolescents, evaluating a reasonably long period of provision of and exposure to active games. Next, strong elements are the incorporating motivational elements for active game play and a comprehensive process evaluation. This trial will provide evidence regarding the potential contribution of active games in prevention of excessive weight gain in

  3. Certification of biological candidates reference materials by neutron activation analysis

    Science.gov (United States)

    Kabanov, Denis V.; Nesterova, Yulia V.; Merkulov, Viktor G.

    2018-03-01

    The paper gives the results of interlaboratory certification of new biological candidate reference materials by neutron activation analysis recommended by the Institute of Nuclear Chemistry and Technology (Warsaw, Poland). The correctness and accuracy of the applied method was statistically estimated for the determination of trace elements in candidate reference materials. The procedure of irradiation in the reactor thermal fuel assembly without formation of fast neutrons was carried out. It excluded formation of interfering isotopes leading to false results. The concentration of more than 20 elements (e.g., Ba, Br, Ca, Co, Ce, Cr, Cs, Eu, Fe, Hf, La, Lu, Rb, Sb, Sc, Ta, Th, Tb, Yb, U, Zn) in candidate references of tobacco leaves and bottom sediment compared to certified reference materials were determined. It was shown that the average error of the applied method did not exceed 10%.

  4. 1996 Activities report on energies and raw materials

    International Nuclear Information System (INIS)

    1996-01-01

    The 1996 activity survey of the French General Directory for Energy and Raw Materials, which main objectives are to preserve the competitiveness of French economy, enhance environmental protection, secure the long term supply safety and maintain the public service basis for energy supply, is presented. The main themes of the survey are: the nuclear safety in Eastern Europe, the electric power inland market, the evolution of the oil market in 1996, the situation of refining in France, restructuring the BRGM (Mining and Geological Research Bureau), followed by brief facts concerning the sustainable energy development, nuclear energy, electric power, electricity and gas common issues, gas, coal, petroleum products, raw materials and underground materials. A series of global diagrams concludes the survey

  5. Charged particle activation analysis of phosphorus in biological materials

    International Nuclear Information System (INIS)

    Masumoto, K.; Yagi, M.

    1983-01-01

    Charged particle activation analysis of phosphorus in biological materials using the 31 P(α,n) sup(34m)Cl reaction has been studied. Since sup(34m)Cl is also produced by the 32 S(α,pn) and the 35 Cl(α,α'n) reactions, the thick-target yield curves on phosphorus, sulfur and chlorine were determined in order to choose the optimum irradiation conditions. As a result, it was found that the activation analysis for phosphorus without interferences from sulfur and chlorine is possible by bombarding with less than 17 MeV alphas. The applicability of this method to biological samples was then examined by irradiating several standard reference materials. It was confirmed that phosphorus can readily be determined at the detection limit of 1μg free from interferences due to the matrix elements. (author)

  6. Application of reference materials for quality assessment in neutron activation analysis

    International Nuclear Information System (INIS)

    Obrusnik, I.; Eckschlager, K.

    1993-01-01

    It is generally accepted that an analytical procedure can be regarded as an information production system yielding information on the composition of the analyzed sample. Thus, information theory can be useful and the quantities characterizing the information properties of an analytical method may be applied not only as evaluation criteria but also as objective functions in the optimization. The usability of information theory is demonstrated on the example of neutron activation analysis. Both precision and bias of NAA results are taken into account together with the possible use of reference materials for quality assessment. The influence of the above-mentioned parameters on information properties such as information gain and profitability of NAA results is discussed in detail. It has been proved that information theory is especially useful in choosing suitable reference materials for the quality assessment of routine analytical procedures not only with respect to matrix and analyte concentration in the sample but also to concentrations and uncertainties of certified values in the CRM used. In the extreme trace analysis, CRMs with relatively large uncertainties and very low certified concentrations can still yield rather high information gain of results. (author) 14 refs.; 9 figs

  7. Low activation material design methodology for reduction of radio-active wastes of nuclear power plant

    International Nuclear Information System (INIS)

    Hasegawa, A.; Satou, M.; Nogami, S.; Kakinuma, N.; Kinno, M.; Hayashi, K.

    2007-01-01

    Most of the concrete shielding walls and pipes around a reactor pressure vessel of a light water reactor become low level radioactive waste at decommission phase because they contain radioactive nuclides by thermal-neutron irradiation during its operation. The radioactivity of some low level radioactive wastes is close to the clearance level. It is very desirable in terms of life cycle cost reduction that the radioactivity of those low level radioactive wastes is decreased below clearance level. In case of light water reactors, however, methodology of low activation design of a nuclear plant has not been established yet because the reactor is a large-scale facility and has various structural materials. The Objectives of this work are to develop low activation material design methodology and material fabrication for reduction of radio-active wastes of nuclear power plant such as reinforced concrete. To realize fabrication of reduced radioactive concrete, it is necessary to develop (1) the database of the chemical composition of raw materials to select low activation materials, (2) the tool for calculation of the neutron flux and the spectrum distribution of nuclear plants to evaluate radioactivity of reactor components, (3) optimization of material process conditions to produce the low activation cement and the low activation steels. Results of the data base development, calculation tools and trial production of low activation cements will be presented. (authors)

  8. Neutron activation analysis for certification of standard reference materials

    International Nuclear Information System (INIS)

    Capote Rodriguez, G.; Perez Zayas, G.; Hernandez Rivero, A.; Ribeiro Guevara, S.

    1996-01-01

    Neutron activation analysis is used extensively as one of the analytical techniques in the certification of standard reference materials. Characteristics of neutron activation analysis which make it valuable in this role are: accuracy multielemental capability to asses homogeneity, high sensitivity for many elements, and essentially non-destructive method. This paper report the concentrations of 30 elements (major, minor and trace elements) in four Cuban samples. The samples were irradiated in a thermal neutron flux of 10 12- 10 13 n.cm 2. s -1. The gamma ray spectra were measured by HPGe detectors and were analyzed using ACTAN program development in Center of Applied Studies for Nuclear Development

  9. Indoor Chemistry: Materials, Ventilation Systems, and Occupant Activities

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, G.C.; Corsi, R.L.; Destaillats, H.; Nazaroff, W.W.; Wells, J.R.

    2006-05-01

    Chemical processes taking place in indoor environments can significantly alter the nature and concentrations of pollutants. Exposure to secondary contaminants generated in these reactions needs to be evaluated in association with many aspects of buildings to minimize their impact on occupant health and well-being. Focusing on indoor ozone chemistry, we describe alternatives for improving indoor air quality by controlling chemical changes related to building materials, ventilation systems, and occupant activities.

  10. Goals, challenges, and successes of managing fusion activated materials

    International Nuclear Information System (INIS)

    El-Guebaly, L.; Massaut, V.; Tobita, K.; Cadwallader, L.

    2008-01-01

    After decades of designing magnetic and inertial fusion power plants, it is timely to develop a new framework for managing the activated (and contaminated) materials that will be generated during plant operation and after decommissioning-a framework that takes into account the lessons learned from numerous international fusion and fission studies and the environmental, political, and present reality in the U.S., Europe, and Japan. This will clearly demonstrate that designers developing fusion facilities will be dealing with the back end of this type of energy production from the beginning of the conceptual design of power plants. It is becoming evident that future regulations for geological burial will be upgraded to assure tighter environmental controls. Along with the political difficulty of constructing new repositories worldwide, the current reality suggests reshaping all aspects of handling the continual stream of fusion active materials. Beginning in the mid 1980s and continuing to the present, numerous fusion designs examined replacing the disposal option with more environmentally attractive approaches, redirecting their attention to recycling and clearance while continuing the development of materials with low activation potential. There is a growing international effort in support of this new trend. In this paper, recent history is analyzed, a new fusion waste management scheme is covered, and possibilities for how its prospects can be improved are examined

  11. Body weight gain in rats by a high-fat diet produces chronodisruption in activity/inactivity circadian rhythm.

    Science.gov (United States)

    Bravo, Rafael; Cubero, Javier; Franco, Lourdes; Mesa, Mónica; Galán, Carmen; Rodríguez, Ana Beatriz; Jarne, Carlos; Barriga, Carmen

    2014-04-01

    In the last few decades, obesity has become one of the most important public health problems. Adipose tissue is an active endocrine tissue which follows a rhythmic pattern in its functions and may produce alterations in certain circadian rhythms. Our aim was to evaluate whether the locomotor activity circadian rhythm could be modified by a hypercaloric diet in rodents. Two groups were considered in the experiment: 16 rats were used as a control group and were fed standard chow; the other group comprised 16 rats fed a high-fat diet (35.8% fat, 35% glucides). The trial lasted 16 weeks. Body weight was measured every week, and a blood sample was extracted every two weeks to quantify triglyceride levels. The activity/inactivity circadian rhythm was logged through actimetry throughout the trial, and analysed using the DAS 24© software package. At the end of the experiment, the high-fat fed rats had obese-like body weights and high plasma triglyceride levels, and, compared with the control group, increased diurnal activity, decreased nocturnal activity, reductions in amplitude, midline estimating statistic of rhythm, acrophase and interdaily stability, and increases in intradaily variability of their activity rhythms. The results thus show how obesity can lead to symptoms of chronodisruption in the body similar to those of ageing.

  12. Versatile equipment for mechanical testing of active materials

    International Nuclear Information System (INIS)

    Bertsch, Johannes; Heimgartner, Peter

    2005-01-01

    At the Paul Scherrer Institute (PSI) 3 different project groups presently perform aging research on active materials. The research fields are fusion, high neutron flux targets and LWR relevant components. Up to now mechanical testing has been performed with small, low dose rate samples behind local shielding, not appropriate for highly activated material. To overcome this situation, a cell concept for active mechanical testing was elaborated and has been erected in PSI's Hotlab. It consists of 4 shielded cells. 3 connected cells are versatile and independently operable for highly beta/gamma active samples. One cell is an alpha/beta/gamma-box which will be realized in a second phase. This paper presents the versatility especially of the beta/gamma-cells: The different user groups perform experiments in these cells, whereas different machines can be placed into the cells. As consequence of the need of heavily shielded cell doors, a special strengthening and levelling of the floor has been required. In all cells the relevant media are installed. Besides the performance of the cells, the project progress as the difficulties and their solutions are described. (Author)

  13. Normal hematopoiesis and lack of β-catenin activation in osteoblasts of patients and mice harboring Lrp5 gain of function mutations

    DEFF Research Database (Denmark)

    Galan-Diez, Marta; Isa, Adiba; Ponzetti, Marco

    2016-01-01

    of hematopoiesis and leukemogenic properties of β-catenin activation in osteoblasts, that lead to development of acute myeloid leukemia (AML). Using mice with gain-of-function (GOF) Lrp5 alleles (Lrp5(A214V)) that recapitulate the human high bone mass (HBM) phenotype, as well as patients with the T253I HBM Lrp5...... mutation, we show here that Lrp5 GOF mutations in both humans and mice do not activate β-catenin signaling in osteoblasts. Consistent with a lack of β-catenin activation in their osteoblasts, Lrp5(A214V) mice have normal trilinear hematopoiesis. In contrast to leukemic mice with constitutive activation...... of β-catenin in osteoblasts (Ctnnb1(CAosb)), accumulation of early myeloid progenitors, a characteristic of AML, myeloid-blasts in blood, and segmented neutrophils or dysplastic megakaryocytes in the bone marrow, are not observed in Lrp5(A214V) mice. Likewise, peripheral blood count analysis in HBM...

  14. Non-linear modeling of active biohybrid materials

    KAUST Repository

    Paetsch, C.

    2013-11-01

    Recent advances in engineered muscle tissue attached to a synthetic substrate motivate the development of appropriate constitutive and numerical models. Applications of active materials can be expanded by using robust, non-mammalian muscle cells, such as those of Manduca sexta. In this study, we propose a model to assist in the analysis of biohybrid constructs by generalizing a recently proposed constitutive law for Manduca muscle tissue. The continuum model accounts (i) for the stimulation of muscle fibers by introducing multiple stress-free reference configurations for the active and passive states and (ii) for the hysteretic response by specifying a pseudo-elastic energy function. A simple example representing uniaxial loading-unloading is used to validate and verify the characteristics of the model. Then, based on experimental data of muscular thin films, a more complex case shows the qualitative potential of Manduca muscle tissue in active biohybrid constructs. © 2013 Elsevier Ltd. All rights reserved.

  15. Neutron activation behavior of NET/ITER divertor structural materials

    International Nuclear Information System (INIS)

    Smid, I.; Weimann, G.; Kny, E.; Kneringer, G.; Reheis, N.

    1995-01-01

    The post-activation behavior of the materials carbon, TZM (99.3 % Mo) and Mo.41Re, as well as of high temperature brazes suitable for their joining after irradiation with 14 MeV neutrons has been evaluated. The activity, dose rate and energy generation after exposure to an ignited fusion plasma is presented for various time steps after shutdown. The impact of the activity and the afterheat production on the handling and storage conditions of retired divertor components is simulated, the required protection for maintenance is discussed. Further the temperature of stored divertor elements after a full time operation in NET was calculated. No major afterheat production will occur and thus no special cooling is to be provided after approximately one month. Taking into account convection and radiation the equilibrium temperature of vertically stored environment/aircooled divertor elements is predicted to be approximately 100 degree C. (author)

  16. Recurring DNA copy number gain at chromosome 9p13 plays a role in the activation of multiple candidate oncogenes in progressing oral premalignant lesions

    International Nuclear Information System (INIS)

    Towle, Rebecca; Tsui, Ivy F L; Zhu, Yuqi; MacLellan, Sara; Poh, Catherine F; Garnis, Cathie

    2014-01-01

    Genomic alteration at chromosome 9p has been previously reported as a frequent and critical event in oral premalignancy. While this alteration is typically reported as a loss driven by selection for CDKN2A deactivation (at 9p21.3), we detect a recurrent DNA copy number gain of ∼2.49 Mbp at chromosome 9p13 in oral premalignant lesions (OPLs) that later progressed to invasive lesions. This recurrent alteration event has been validated using fluorescence in situ hybridization in an independent set of OPLs. Analysis of publicly available gene expression datasets aided in identifying three oncogene candidates that may have driven selection for DNA copy number increases in this region (VCP, DCTN3, and STOML2). We performed in vitro silencing and activation experiments for each of these genes in oral cancer cell lines and found that each gene is independently capable of upregulating proliferation and anchorage-independent growth. We next analyzed the activity of each of these genes in biopsies of varying histological grades that were obtained from a diseased oral tissue field in a single patient, finding further molecular evidence of parallel activation of VCP, DCTN3, and STOML2 during progression from normal healthy tissue to invasive oral carcinoma. Our results support the conclusion that DNA gain at 9p13 is important to the earliest stages of oral tumorigenesis and that this alteration event likely contributes to the activation of multiple oncogene candidates capable of governing oral cancer phenotypes

  17. Fusion material development program in the broader approach activities

    Energy Technology Data Exchange (ETDEWEB)

    Nishitani, T. [Directorates of Fusion Energy Research: Naka, Ibaraki, Japan Atomic Energy Agency, Naka, Ibaraki (Japan); Tanigawa, H.; Jitsukawa, S. [Japan Atomic Energy Agency, Tokai-mura, Naga-gun, Ibaraki-ken (Japan); Hayashi, K.; Takatsu, H. [Fusion Research and Development Directorate, Japan Momie Energy Agency, Ibaraki-ken (Japan); Yamanishi, T. [Tritium Process Laboratory, Japan Atomic Energy Research Institute, Tokai-mura, Ibaraki-ken (Japan); Tsuchiya, K. [Directorates of Fusion Energy Research, JAEA, Higashi-ibaraki-gun, Ibaraki-ken (Japan); MoIslang, A. [Forschungszentrum Karlsruhe GmbH, FZK, Karlsruhe (Germany); Baluc, N. [EPFL-Ecole Polytechnique Federale de Lausanne, Association Euratom-Confederation Suisse, UHD - CRPP, PPB, Lausanne (Switzerland); Pizzuto, A. [ENEA CR Frascat, Frascati (Italy); Hodgson, E.R. [CIEMAT-Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, Association Euratom-CIEMAT, Madrid (Spain); Lasser, R.; Gasparotto, M. [EFDA CSU Garching (Germany)

    2007-07-01

    Full text of publication follows: The world fusion community is now launching construction of ITER, the first nuclear-grade fusion machine in the world. In parallel to the ITER program, Broader Approach (BA) activities are initiated by EU and Japan, mainly at Rokkasho BA site in Japan. The BA activities include the International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities (IFMIF-EVEDA), the International Fusion Energy Research Center (IFERC), and the Satellite Tokamak. IFERC consists of three sub project; a DEMO Design and R and D coordination Center, a Computational Simulation Center, and an ITER Remote Experimentation Center. Technical R and Ds mainly on fusion materials will be implemented as a part of the DEMO Design and R and D coordination Center. Based on the common interest of each party toward DEMO, R and Ds on a) reduced activation ferritic martensitic (RAFM) steels as a DEMO blanket structural material, SiCf/SiC composites, advanced tritium breeders and neutron multiplier for DEMO blankets, and Tritium Technology were selected and assessed by European and Japanese experts. In the R and D on the RAFM steels, the fabrication technology, techniques to incorporate the fracture/rupture properties of the irradiated materials, and methods to predict the deformation and fracture behaviors of structures under irradiation will be investigated. For SiCf/SiC composites, standard methods to evaluate high-temperature and life-time properties will be developed. Not only for SiCf/SiC but also related ceramics, physical and chemical properties such as He and H permeability and absorption will be investigated under irradiation. As the advanced tritium breeder R and D, Japan and EU plan to establish the production technique for advanced breeder pebbles of Li{sub 2}TiO{sub 3} and Li{sub 4}SiO{sub 4}, respectively. Also physical, chemical, and mechanical properties will be investigated for produced breeder pebbles. For the

  18. Development of antimicrobial active packaging materials based on gluten proteins.

    Science.gov (United States)

    Gómez-Heincke, Diana; Martínez, Inmaculada; Partal, Pedro; Guerrero, Antonio; Gallegos, Críspulo

    2016-08-01

    The incorporation of natural biocide agents into protein-based bioplastics, a source of biodegradable polymeric materials, manufactured by a thermo-mechanical method is a way to contribute to a sustainable food packaging industry. This study assesses the antimicrobial activity of 10 different biocides incorporated into wheat gluten-based bioplastics. The effect that formulation, processing, and further thermal treatments exert on the thermo-mechanical properties, water absorption characteristics and rheological behaviour of these materials is also studied. Bioplastics containing six of the 10 examined bioactive agents have demonstrated suitable antimicrobial activity at 37 °C after their incorporation into the bioplastic. Moreover, the essential oils are able to create an antimicrobial atmosphere within a Petri dish. Depending on the selected biocide, its addition may alter the bioplastics protein network in a different extent, which leads to materials exhibiting less water uptake and different rheological and thermo-mechanical behaviours. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  19. Remembering with Gains and Losses: Effects of Monetary Reward and Punishment on Successful Encoding Activation of Source Memories

    Science.gov (United States)

    Shigemune, Yayoi; Tsukiura, Takashi; Kambara, Toshimune; Kawashima, Ryuta

    2014-01-01

    The motivation of getting rewards or avoiding punishments reinforces learning behaviors. Although the neural mechanisms underlying the effect of rewards on episodic memory have been demonstrated, there is little evidence of the effect of punishments on this memory. Our functional magnetic resonance imaging (fMRI) study investigated the effects of monetary rewards and punishments on activation during the encoding of source memories. During encoding, participants memorized words (item) and locations of presented words (source) under 3 conditions (Reward, Punishment, and Control). During retrieval, participants retrieved item and source memories of the words and were rewarded or penalized according to their performance. Source memories encoded with rewards or punishments were remembered better than those without such encoding. fMRI data demonstrated that the ventral tegmental area and substantia nigra and nucleus accumbens activations reflected both the processes of reward and punishment, whereas insular activation increased as a linear function of punishment. Activation in the hippocampus and parahippocampal cortex predicted subsequent retrieval success of source memories. Additionally, correlations between these reward/punishment-related regions and the hippocampus were significant. The successful encoding of source memories could be enhanced by punishments and rewards, and interactions between reward/punishment-related regions and memory-related regions could contribute to memory enhancement by reward and/or punishment. PMID:23314939

  20. GQ-16, a Novel Peroxisome Proliferator-activated Receptor gamma (PPAR gamma) Ligand, Promotes Insulin Sensitization without Weight Gain

    NARCIS (Netherlands)

    Amato, Angelica A.; Rajagopalan, Senapathy; Lin, Jean Z.; Carvalho, Bruno M.; Figueira, Ana C. M.; Lu, Jenny; Ayers, Stephen D.; Mottin, Melina; Silveira, Rodrigo L.; Telles de Souza, Paulo; Mourao, Rosa H. V.; Saad, Mario J. A.; Togashi, Marie; Simeoni, Luiz A.; Abdalla, Dulcineia S. P.; Skaf, Munir S.; Polikparpov, Igor; Lima, Maria C. A.; Galdino, Suely L.; Brennan, Richard G.; Baxter, John D.; Pitta, Ivan R.; Webb, Paul; Phillips, Kevin J.; Neves, Francisco A. R.

    2012-01-01

    The recent discovery that peroxisome proliferator-activated receptor gamma (PPAR gamma) targeted anti-diabetic drugs function by inhibiting Cdk5-mediated phosphorylation of the receptor has provided a new viewpoint to evaluate and perhaps develop improved insulin-sensitizing agents. Herein we report

  1. Remembering with gains and losses: effects of monetary reward and punishment on successful encoding activation of source memories.

    Science.gov (United States)

    Shigemune, Yayoi; Tsukiura, Takashi; Kambara, Toshimune; Kawashima, Ryuta

    2014-05-01

    The motivation of getting rewards or avoiding punishments reinforces learning behaviors. Although the neural mechanisms underlying the effect of rewards on episodic memory have been demonstrated, there is little evidence of the effect of punishments on this memory. Our functional magnetic resonance imaging (fMRI) study investigated the effects of monetary rewards and punishments on activation during the encoding of source memories. During encoding, participants memorized words (item) and locations of presented words (source) under 3 conditions (Reward, Punishment, and Control). During retrieval, participants retrieved item and source memories of the words and were rewarded or penalized according to their performance. Source memories encoded with rewards or punishments were remembered better than those without such encoding. fMRI data demonstrated that the ventral tegmental area and substantia nigra and nucleus accumbens activations reflected both the processes of reward and punishment, whereas insular activation increased as a linear function of punishment. Activation in the hippocampus and parahippocampal cortex predicted subsequent retrieval success of source memories. Additionally, correlations between these reward/punishment-related regions and the hippocampus were significant. The successful encoding of source memories could be enhanced by punishments and rewards, and interactions between reward/punishment-related regions and memory-related regions could contribute to memory enhancement by reward and/or punishment.

  2. The Positive Influence of Active Learning in a Lecture Hall: An Analysis of Normalised Gain Scores in Introductory Environmental Engineering

    Science.gov (United States)

    Kinoshita, Timothy J.; Knight, David B.; Gibbes, Badin

    2017-01-01

    Burgeoning college enrolments and insufficient funding to higher education have expanded the use of large lecture courses. As this trend continues, it is important to ensure that students can still learn in those challenging learning environments. Within education broadly and undergraduate engineering specifically, active learning pedagogies have…

  3. Designing Gain- and Loss-Framed Messages to Increase Physical Activity among University Students Living in two Different Cultures

    Directory of Open Access Journals (Sweden)

    Pelin Ozgur Polat

    2015-10-01

    The primary aim of this project is to gather information through using different methods and investigate the determinants of message persuasiveness in university students from the British and Turkish cultures in order to design effective physical activity messages leading intention, attitude and behaviour change. The results of the finalized studies showed the importance of using both qualitative and quantitative methods in message design process.

  4. Thermally activated creep and fluidization in flowing disordered materials

    Science.gov (United States)

    Merabia, Samy; Detcheverry, François

    2016-11-01

    When submitted to a constant mechanical load, many materials display power law creep followed by fluidization. A fundamental understanding of these processes is still far from being achieved. Here, we characterize creep and fluidization on the basis of a mesoscopic viscoplastic model that includes thermally activated yielding events and a broad distribution of energy barriers, which may be lowered under the effect of a local deformation. We relate the creep exponent observed before fluidization to the width of barrier distribution and to the specific form of stress redistribution following yielding events. We show that Andrade creep is accompanied by local strain hardening driven by stress redistribution and find that the fluidization time depends exponentially on the applied stress. The simulation results are interpreted in the light of a mean-field analysis, and should help in rationalizing the creep phenomenology in disordered materials.

  5. MACRO DEFECT FREE MATERIALS; THE CHALLENGE OF MECHANOCHEMICAL ACTIVATION

    Directory of Open Access Journals (Sweden)

    MILAN DRÁBIK

    2012-12-01

    Full Text Available Macro-defect-free (MDF materials belong, according to Odler’s categorisation, to the type of materials where polymers may be successfully combined with cements and water to produce also the parameters of technological novelty and interests. A challenge, which has not been followed or indicated by now, is the option to intensify mixing of dry cement and polymer. The mechanochemical pre-reactions of dry MDF raw mixes consisting of Portland cement and polyphosphate, together with the model of atomic-level interpretations of the formed functional interfaces are proposed, experimentally tested and discussed in the present paper. The results ultimately show the activation of studied system due to the mechanochemical treatment, which consists in the initiation and measurable formation of Al(Fe–O–P cross-links already in the treated raw mixes. The mechanochemical activation of raw mixes in the high energy planetary mill for the duration of 5 minutes is proposed as the specific mixing and activation / pre-reaction step within the entire MDF synthesis procedure.

  6. 8-band and 14-band kp modeling of electronic band structure and material gain in Ga(In)AsBi quantum wells grown on GaAs and InP substrates

    Energy Technology Data Exchange (ETDEWEB)

    Gladysiewicz, M.; Wartak, M. S. [Faculty of Fundamental Problems of Technology, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Department of Physics and Computer Science, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5 (Canada); Kudrawiec, R. [Faculty of Fundamental Problems of Technology, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland)

    2015-08-07

    The electronic band structure and material gain have been calculated for GaAsBi/GaAs quantum wells (QWs) with various bismuth concentrations (Bi ≤ 15%) within the 8-band and 14-band kp models. The 14-band kp model was obtained by extending the standard 8-band kp Hamiltonian by the valence band anticrossing (VBAC) Hamiltonian, which is widely used to describe Bi-related changes in the electronic band structure of dilute bismides. It has been shown that in the range of low carrier concentrations n < 5 × 10{sup 18 }cm{sup −3}, material gain spectra calculated within 8- and 14-band kp Hamiltonians are similar. It means that the 8-band kp model can be used to calculate material gain in dilute bismides QWs. Therefore, it can be applied to analyze QWs containing new dilute bismides for which the VBAC parameters are unknown. Thus, the energy gap and electron effective mass for Bi-containing materials are used instead of VBAC parameters. The electronic band structure and material gain have been calculated for 8 nm wide GaInAsBi QWs on GaAs and InP substrates with various compositions. In these QWs, Bi concentration was varied from 0% to 5% and indium concentration was tuned in order to keep the same compressive strain (ε = 2%) in QW region. For GaInAsBi/GaAs QW with 5% Bi, gain peak was determined to be at about 1.5 μm. It means that it can be possible to achieve emission at telecommunication windows (i.e., 1.3 μm and 1.55 μm) for GaAs-based lasers containing GaInAsBi/GaAs QWs. For GaInAsBi/Ga{sub 0.47}In{sub 0.53}As/InP QWs with 5% Bi, gain peak is predicted to be at about 4.0 μm, i.e., at the wavelengths that are not available in current InP-based lasers.

  7. Certification of standard reference materials employing neutron activation analysis

    International Nuclear Information System (INIS)

    Capote Rodriguez, G.; Hernandez Rivero, A.; Molina Insfran, J.; Ribeiro Guevara, S.; Santana Encinosa, C.; Perez Zayas, G.

    1997-01-01

    Neutron activation analysis (Naa) is used extensively as one of the analytical techniques in the certification of standard reference materials (Srm). Characteristics of Naa which make it valuable in this role are: accuracy; multielemental capability; ability to assess homogeneity; high sensitivity for many elements, and essentially non-destructive method. This paper reports the concentrations of thirty elements (major, minor and trace elements) in four Cuban Srm's. The samples were irradiated in a thermal neutron flux of 10 12 -10 13 neutrons.cm -2 .s -1 . The gamma-ray spectra were measured by HPGe detectors and were analysed using ACTAN program, developed in CEADEN. (author) [es

  8. Fissile materials in solution concentration measured by active neutron interrogation

    International Nuclear Information System (INIS)

    Romeyer Dherbey, J.; Passard, Ch.; Cloue, J.; Bignan, G.

    1993-01-01

    The use of the active neutron interrogation to measure the concentration of plutonium contained in flow solutions is particularly interesting for fuel reprocessing plants. Indeed, this method gives a signal which is in a direct relation with the fissile materials concentration. Moreover, it is less sensitive to the gamma dose rate than the other nondestructive methods. Two measure methods have been evolved in CEA. Their principles are given into details in this work. The first one consists to detect fission delayed neutrons induced by a 252 Cf source. In the second one fission prompt neutrons induced by a neutron generator of 14 MeV are detected. (O.M.)

  9. Neutron activation analysis of trace elements in IAEA reference materials

    International Nuclear Information System (INIS)

    Cheema, M.N.; Hasany, S.M.; Hanif, I.; Chaudhry, M.S.; Qureshi, I.H.

    1978-09-01

    Analytical Chemistry Group of Nuclear Chemistry Division at PINSTECH has been participating in IAEA Intercomparison programme of analytical quality control since 1972. So far fifteen samples of a variety of materials received from the Agency have been analyzed for different minor and trace elements. Mostly destructive and non-destructive neutron activation analysis techniques have been used for elemental analysis. In this report the description of the samples and the experimental procedures employed have been mentioned. The results of elemental analysis have been reported and compared with IAEA values which are based on the average computed from the results of different participating laboratories. (authors)

  10. Should I Gain Weight?

    Science.gov (United States)

    ... Videos for Educators Search English Español Should I Gain Weight? KidsHealth / For Teens / Should I Gain Weight? ... something about it. Why Do People Want to Gain Weight? Some of the reasons people give for ...

  11. Neutron activation determination of phosphorus in semiconductor materials

    International Nuclear Information System (INIS)

    Verevkin, G.V.; Gil'bert, Eh.N.; Gol'dshtejn, M.M.; Yudelevich, I.G.; Yurchenko, V.K.

    1976-01-01

    The solvent extraction of molybdophosphoric acid (MPA) with benzene and dichloroethane solutions of dioctylsulphoxide has been studied. A neutron-activation method has been worked out of determining phosphorus in semiconductor silicon, high purity gallium, and homoepitaxial films of gallium arsenide. The method is based on separation of radiochemically pure phosphorus in the form of MPA by extraction with 0.2 M solution of dioctylsulphoxide in benzene and measurement of 32 P activity on a liquid scintillation spectrometer. The method makes it possible to determine phosphorus in the materials enumerated with a limit of detection of 1.9x10 -10 g and a relative standard deviation of not more than 0.05

  12. Study of adsorption properties on lithium doped activated carbon materials

    International Nuclear Information System (INIS)

    Los, S.; Daclaux, L.; Letellier, M.; Azais, P.

    2005-01-01

    A volumetric method was applied to study an adsorption coefficient of hydrogen molecules in a gas phase on super activated carbon surface. The investigations were focused on getting the best possible materials for the energy storage. Several treatments on raw samples were used to improve adsorption properties. The biggest capacities were obtain after high temperature treatment at reduced atmosphere. The adsorption coefficient at 77 K and 2 MPa amounts to 3.158 wt.%. The charge transfer between lithium and carbon surface groups via the doping reaction enhanced the energy of adsorption. It was also found that is a gradual decrease in the adsorbed amount of H 2 molecules due to occupation active sites by lithium ions. (author)

  13. Materials design data for reduced activation martensitic steel type EUROFER

    Energy Technology Data Exchange (ETDEWEB)

    Tavassoli, A.-A.F. E-mail: tavassoli@cea.fr; Alamo, A.; Bedel, L.; Forest, L.; Gentzbittel, J.-M.; Rensman, J.-W.; Diegele, E.; Lindau, R.; Schirra, M.; Schmitt, R.; Schneider, H.C.; Petersen, C.; Lancha, A.-M.; Fernandez, P.; Filacchioni, G.; Maday, M.F.; Mergia, K.; Boukos, N.; Baluc,; Spaetig, P.; Alves, E.; Lucon, E

    2004-08-01

    Materials design limits derived so far from the data generated in Europe for the reduced activation ferritic/martensitic (RAFM) steel type Eurofer are presented. These data address the short-term needs of the ITER Test Blanket Modules and a DEMOnstration fusion reactor. Products tested include plates, bars, tubes, TIG and EB welds, as well as powder consolidated blocks and solid-solid HIP joints. Effects of thermal ageing and low dose neutron irradiation are also included. Results are sorted and screened according to design code requirements before being introduced in reference databases. From the physical properties databases, variations of magnetic properties, modulus of elasticity, density, thermal conductivity, thermal diffusivity, specific heat, mean and instantaneous linear coefficients of thermal expansion versus temperature are derived. From the tensile and creep properties databases design allowable stresses are derived. From the instrumented Charpy impact and fracture toughness databases, ductile to brittle transition temperature, toughness and behavior of materials in different fracture modes are evaluated. From the fatigue database, total strain range versus number of cycles to failure curves are plotted and used to derive fatigue design curves. Cyclic curves are also derived and compared with monotonic hardening curves. Finally, irradiated and aged materials data are compared to ensure that the safety margins incorporated in unirradiated design limits are not exceeded.

  14. Potential active materials for photo-supercapacitor: A review

    Science.gov (United States)

    Ng, C. H.; Lim, H. N.; Hayase, S.; Harrison, I.; Pandikumar, A.; Huang, N. M.

    2015-11-01

    The need for an endless renewable energy supply, typically through the utilization of solar energy in most applications and systems, has driven the expansion, versatility, and diversification of marketed energy storage devices. Energy storage devices such as hybridized dye-sensitized solar cell (DSSC)-capacitors and DSSC-supercapacitors have been invented for energy reservation. The evolution and vast improvement of these devices in terms of their efficiencies and flexibilities have further sparked the invention of the photo-supercapacitor. The idea of coupling a DSSC and supercapacitor as a complete energy conversion and storage device arose because the solar energy absorbed by dye molecules can be efficiently transferred and converted to electrical energy by adopting a supercapacitor as the energy delivery system. The conversion efficiency of a photo-supercapacitor is mainly dependent on the use of active materials during its fabrication. The performances of the dye, photoactive metal oxide, counter electrode, redox electrolyte, and conducting polymer are the primary factors contributing to high-energy-efficient conversion, which enhances the performance and shelf-life of a photo-supercapacitor. Moreover, the introduction of compact layer as a primary adherent film has been earmarked as an effort in enhancing power conversion efficiency of solar cell. Additionally, the development of electrolyte-free solar cell such as the invention of hole-conductor or perovskite solar cell is currently being explored extensively. This paper reviews and analyzes the potential active materials for a photo-supercapacitor to enhance the conversion and storage efficiencies.

  15. Material Science Activities for Fusion Reactors in Kazakhstan

    International Nuclear Information System (INIS)

    Tazhibayeva, I.; Kenzhin, E.; Kulsartov, T.; Shestakov, V.; Chikhray, Y.; Azizov, E.; Filatov, O.; Chernov, V.M.

    2007-01-01

    Full text of publication follows: Paper contains results of fusion material testing national program and results of activities on creation of material testing spherical tokamak. Hydrogen isotope behavior (diffusion, permeation, and accumulation) in the components of the first wall and divertor was studied taking into account temperature, pressure, and reactor irradiation. There were carried out out-of-pile and in-pile (reactors IVG-IM, WWRK, RA) studies of beryllium of various grades (TV-56, TShG-56, DV-56, TGP-56, TIP-56), graphites (RG-T, MPG-8, FP 479, R 4340), molybdenum, tungsten, steels (Cr18Ni10Ti, Cr16Ni15, MANET, F82H), alloys V-(4-6)Cr-( 4-5)Ti, Cu+1%Cr+0.1%Zr, and double Be/Cu and triple Be/Cu/steel structures. Tritium permeability from eutectic Pb+17%Li through steels Cr18Ni10Ti, Cr16Ni15, MANET, and F82H were studied taking into account protective coating effects. The tritium production rate was experimentally assessed during in-pile and post-reactor experiments. There were carried out radiation tests of ceramic Li 2 TiO 3 (96% enrichment by Li-6) with in-situ registration of released tritium and following post-irradiation material tests of irradiated samples. Verification of computer codes for simulation of accidents related to LOCA in ITER reactor was carried out. Codes' verification was carried out for a mockup of first wall in a form of three-layer cylinder of beryllium, bronze (Cu-Cr-Zr) and stainless steel. At present Kazakhstan Tokamak for Material testing (tokamak KTM) is created in National Nuclear Center of Republic of Kazakhstan in cooperation with Russian Federation organizations (start-up is scheduled on 2008). Tokamak KTM allows for expansion and specification of the studies and tests of materials, protection options of first wall, receiving divertor tiles and divertor components, methods for load reduction at divertor, and various options of heat/power removal, fast evacuation of divertor volume and development of the techniques for

  16. Oral Administration of Semicarbazide Limits Weight Gain together with Inhibition of Fat Deposition and of Primary Amine Oxidase Activity in Adipose Tissue

    Directory of Open Access Journals (Sweden)

    Josep Mercader

    2011-01-01

    Full Text Available An enzyme hitherto named semicarbazide-sensitive amine oxidase (SSAO, involved in the oxidation of primary amines, is abundantly expressed in adipocytes. Although SSAO physiological functions remain unclear, several molecules inhibiting its activity have been described to limit fat accumulation in preadipocyte cultures or to reduce body weight gain in obese rodents. Here, we studied whether oral administration of semicarbazide, a prototypical SSAO inhibitor, limits fat deposition in mice. Prolonged treatment with semicarbazide at 0.125% in drinking water limited food and water consumption, hampered weight gain, and deeply impaired fat deposition. The adiposomatic index was reduced by 31%, while body mass was reduced by 15%. Such treatment completely inhibited SSAO, but did not alter MAO activity in white adipose tissue. Consequently, the insulin-like action of the SSAO substrate benzylamine on glucose transport was abolished in adipocytes from semicarbazide-drinking mice, while their insulin sensitivity was not altered. Although semicarbazide is currently considered as a food contaminant with deleterious effects, the SSAO inhibition it induces appears as a novel concept to modulate adipose tissue development, which is promising for antiobesity drug discovery.

  17. Precision of neutron activation analysis for environmental biological materials

    International Nuclear Information System (INIS)

    Hamaguchi, Hiroshi; Iwata, Shiro; Koyama, Mutsuo; Sasajima, Kazuhisa; Numata, Yuichi.

    1977-01-01

    Between 1973 and 1974 a special committee ''Research on the application of neutron activation analysis to the environmental samples'' had been organized at the Research Reactor Institute, Kyoto University. Eleven research groups composed mainly of the committee members cooperated in the intercomparison programme of the reactor neutron activation analysis of NBS standard reference material, 1571 Orchard Leaves and 1577 Bovine Liver. Five different type of reactors were used for the neutron irradiation; i.e. KUR reactor of the Research Reactor Institute, Kyoto University, TRIGA MARK II reactor of the Institute for Atomic Energy, Rikkyo University, and JRR-2, JRR-3, JRR-4 reactor of Japan Atomic Energy Research Institute. Analyses were performed mainly by instrumental method. Precision of the analysis of 23 elements in Orchard Leaves and 13 elements in Bovine Liver presented by the different research groups was shown in table 4 and 5, respectively. The coefficient of variation for these elements was from several to -- 30 percent. Averages given to these elements agreed well with the NBS certified or reference values. Thus, from the practical point of view for the routine multielement analysis of environmental samples, the validity of the instrumental neutron activation technique for this purpose has been proved. (auth.)

  18. Development of active and sensitive material systems based on composites

    Science.gov (United States)

    Asanuma, Hiroshi

    2002-07-01

    This paper describes new concepts proposed by the author to realize active and sensitive structural material systems. Two examples of multifunctional composites were fabricated and evaluated in this study as follows: (1) An active laminate of aluminum plate (works as muscle), epoxy film (as insulator), unidirectional CFRP prepreg (as bone and blood vessel) and copper foil electrode (to apply voltage on CFRP) was made with an embedded optical fiber multiply fractured in the CFRP layer (works as nerve), of which curvature change could be effectively monitored with the fractured optical fiber. (2) A stainless steel fiber/aluminum active composite with embedded Ti oxide/Ti composite fiber was fabricated. The Ti oxide/Ti fiber could work as a sensor for temperature by removing a part of the oxide before embedment to make a metallic contact between the embedded titanium fiber and aluminum matrix to be able to generate thermal electromotive force, and also could work as a sensor for strain and as a heater for actuation. In the both cases, the outputs from their embedded sensors can be used to control their actuations.

  19. Patient–Provider Communication and Counseling about Gestational Weight Gain and Physical Activity: A Qualitative Study of the Perceptions and Experiences of Latinas Pregnant with their First Child

    Directory of Open Access Journals (Sweden)

    Ana Cristina Lindsay

    2017-11-01

    Full Text Available Latina women in the United States (U.S. are disproportionately affected by obesity and are more likely to begin pregnancy overweight and gain excessive weight during pregnancy. The prenatal care period represents a window of opportunity for women to access the healthcare system and receive preventive services, education, nutritional support, and other social services to improve pregnancy outcomes. Excessive gestational weight gain (GWG has numerous negative short- and long-term consequences for both the mother and newborn. We explored nulliparous Latina women’s perceptions about their experiences communicating with their primary healthcare provider about GWG and physical activity (PA to identify possible intervention targets using in-depth, semi-structured interviews. Bilingual, trained research staff conducted 23 interviews with first-time pregnant Latinas between 22 and 36 weeks of gestation. Interviews were transcribed verbatim and analyzed using content analysis. Salient text passages were extracted, shortened, coded, and grouped into categories. Women, including those who self-identified as being overweight or obese prior to pregnancy, reported receiving limited or no advice from their healthcare providers about GWG or PA. Additionally, analysis revealed that although participants value information received from the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC program counselors, they would like to receive more information from their primary healthcare providers about adequate GWG. Furthermore, study findings indicate that some participants received conflicting information regarding PA during pregnancy. Study findings suggest the need for increased integration of communication and counseling about GWG and PA into prenatal care services to promote healthy weight gain and PA among low-income Latina women.

  20. Modulating activity in the prefrontal cortex changes decision-making for risky gains and losses: a transcranial direct current stimulation study.

    Science.gov (United States)

    Ye, Hang; Chen, Shu; Huang, Daqiang; Wang, Siqi; Luo, Jun

    2015-06-01

    When making choices under uncertainty, people usually consider both the risks and benefits of each option. Previous studies have found that weighing of risks and benefits during decision-making involves a complex neural network that includes the dorsolateral prefrontal cortex (DLPFC), but the causal effect of this network on risk decision-making has remained unclear. This experiment was based on a risk-measurement table designed to provide a direct measure of risk preference, with a weighted value of the choices (denoted as weighted risk aversion, WRA) as an index of the participant's degree of risk aversion. We studied whether bifrontal transcranial direct current stimulation (tDCS) applied over the right and left prefrontal cortex can change the balance of risky vs. safe responses under both gain frame and loss frame. A total of 60 volunteers performed risk tasks while receiving either anodal over the right with cathodal over the left DLPFC, anodal over the left with cathodal over the right DLPFC, or sham stimulation. The participants tended to choose more risky options in the gain frame and more safe options in the loss frame after the right anodal/left cathodal tDCS. We also found that right anodal/left cathodal tDCS significantly decreased the WRA values compared with those associated with sham stimulation. These findings extend the notion that DLPFC activity is critical for risk decision-making, indicating an asymmetric role of the right DLPFC in the gain frame vs. the loss frame of risk decision-making. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Detection of nuclear material by photon activation inside cargo containers

    Science.gov (United States)

    Gmar, Mehdi; Berthoumieux, Eric; Boyer, Sébastien; Carrel, Frédérick; Doré, Diane; Giacri, Marie-Laure; Lainé, Frédéric; Poumarède, Bénédicte; Ridikas, Danas; Van Lauwe, Aymeric

    2006-05-01

    Photons with energies above 6 MeV can be used to detect small amounts of nuclear material inside large cargo containers. The method consists in using an intense beam of high-energy photons (bremsstrahlung radiation) in order to induce reactions of photofission on actinides. The measurement of delayed neutrons and delayed gammas emitted by fission products brings specific information on localization and quantification of the nuclear material. A simultaneous measurement of both of these delayed signals can overcome some important limitations due to matrix effects like heavy shielding and/or the presence of light elements as hydrogen. We have a long experience in the field of nuclear waste package characterization by photon interrogation and we have demonstrated that presently the detection limit can be less than one gram of actinide per ton of package. Recently we tried to extend our knowledge to assess the performance of this method for the detection of special nuclear materials in sea and air freights. This paper presents our first results based on experimental measurements carried out in the SAPHIR facility, which houses a linear electron accelerator with the energy range from 15 MeV to 30 MeV. Our experiments were also modeled using the full scale Monte Carlo techniques. In addition, and in a more general frame, due to the lack of consistent data on photonuclear reactions, we have been working on the development of a new photonuclear activation file (PAF), which includes cross sections for more than 600 isotopes including photofission fragment distributions and delayed neutron tables for actinides. Therefore, this work includes also some experimental results obtained at the ELSA electron accelerator, which is more adapted for precise basic nuclear data measurements.

  2. Neutron activation analysis of new botanical reference materials. Pt. 2

    International Nuclear Information System (INIS)

    Kucera, J.; Soukal, L.

    1993-01-01

    The certified, information, and other values of elemental contents were compared with results of neutron activation analysis (NAA) for the new Czechoslovak botanical reference materials (RMs) Green Algae 12-02-02, Lucerne 12-02-03, Wheat Bread Fluor 12-02-04, and Rye Bread Flour 12-02-05. These were prepared by the Institute of Radioecology and Applied Nuclear Techniques (IRANT), Kosice, and statistically evaluated after interlaboratory comparisons. For the majority of elements, a very good agreement was found between the IRANT values and the results of NAA. In several cases, however, significant differences were detected; possible analytical reasons for the differences and the suitability of a purely statistical evaluation of intercomparison results without analytical considerations for RM certification are discussed. (orig.)

  3. Reactor neutron activation analysis on reference materials from intercomparison runs

    International Nuclear Information System (INIS)

    Pantelica, A.; Salagean, M.

    2003-01-01

    A review of using the Instrumental Neutron Activation Analysis (INAA) technique in our laboratory to determine major, minor and trace elements in mineral and biological samples from international intercomparison runs organised by IAEA Vienna, IAEA-MEL Monaco, 'pb-anal' Kosice, INCT Warszawa and IPNT Krakow is presented. Neutron irradiation was carried out at WWR-S reactor in Bucharest (short and long irradiation) during 1982-1997 and at TRIGA reactor in Pitesti (long irradiation) during the later period. The following type of materials were analysed: soils, marine sediments, uranium phosphate ore, water sludge, copper flue dust, whey powder, yeast, cereal flour (rye and wheat), marine animal tissue (mussel, garfish and tuna fish), as well as vegetal tissue (seaweed, cabbage, spinach, alfalfa, algae, tea leaves and herbs). The following elements could be, in general, determined: Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Lu, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Yb and Zn of long-lived radionuclides, as well as Al, Ca, Cl, Cu, Mg, Mn, and Ti of short-lived radionuclides. Data obtained in our laboratory for various matrix samples presented and compared with the intercomparison certified values. The intercomparison exercises offer to the participating laboratories the opportunity to test the accuracy of their analytical methods as well as to acquire valuable Reference Materials/ standards for future analytical applications. (authors)

  4. Overview of Indian activities on fusion reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Srikumar, E-mail: sbanerjee@barc.gov.in

    2014-12-15

    This paper on overview of Indian activities on fusion reactor materials describes in brief the efforts India has made to develop materials for the first wall of a tokamak, its blanket and superconducting magnet coils. Through a systematic and scientific approach, India has developed and commercially produced reduced activation ferritic/martensitic (RAFM) steel that is comparable to Eurofer 97. Powder of low activation ferritic/martensitic oxide dispersion strengthened steel with characteristics desired for its application in the first wall of a tokamak has been produced on the laboratory scale. V–4Cr–4Ti alloy was also prepared in the laboratory, and kinetics of hydrogen absorption in this was investigated. Cu–1 wt%Cr–0.1 wt%Zr – an alloy meant for use as heat transfer elements for hypervapotrons and heat sink for the first wall – was developed and characterized in detail for its aging behavior. The role of addition of a small quantity of Zr in its improved fatigue performance was delineated, and its diffusion bonding with both W and stainless steel was achieved using Ni as an interlayer. The alloy was produced in large quantities and used for manufacturing both the heat transfer elements and components for the International Thermonuclear Experimental Reactor (ITER). India has proposed to install and test a lead–lithium cooled ceramic breeder test blanket module (LLCB-TBM) at ITER. To meet this objective, efforts have been made to produce and characterize Li{sub 2}TiO{sub 3} pebbles, and also improve the thermal conductivity of packed beds of these pebbles. Liquid metal loops have been set up and corrosion behavior of RAFM steel in flowing Pb–Li eutectic has been studied in the presence as well as absence of magnetic fields. To prevent permeation of tritium and reduce the magneto-hydro-dynamic drag, processes have been developed for coating alumina on RAFM steel. Apart from these activities, different approaches being attempted to make the U

  5. Strengthening global physical protection practices; gaining better information on national practices for protection of weapons-usable material. Keynote address/session 3

    International Nuclear Information System (INIS)

    Bunn, G.; Rinne, R.

    2001-01-01

    Full text: Unlike the Non-Proliferation Treaty requirement that non-nuclear-weapon parties provide 'safeguards' information to the IAEA on their nuclear materials and their state systems for accounting and control, there is no related requirement to provide information on state systems of physical protection. A review of 1997 IAEA and Stanford physical protection conference proceedings showed both the absence of information on important practices from many states and the great variation in practices from state to state. Besides the lack of internationally required standards for domestic protection, reasons for the variations described in Stanford-Sandia National Laboratories research include: differences in states' perceptions of the threats to their materials; differences in their abilities to pay the cost of stronger physical protection; differences in their laws and regulatory practices in general; and differences in their cultural attitudes - for example, attitudes toward whether to arm personnel guarding weapon-usable material or to require clearances for personnel with access to such material. The information presented to the 1997 IAEA and Stanford conferences was supplied voluntarily. The two global documents which provide norms for physical protection do not require submission of such information. These are the 1980 Convention on Physical Protection of Nuclear Material and the 1999 IAEA INFCIRC/225/Rev.4. This means that, without bilateral cooperation, no state can find out how other states are protecting their nuclear material. Yet, as IAEA Director General El Baradei has said, '[I]t is not a matter of indifference to other States whether and to what extent [physical protection] responsibility is fulfilled. ...The need for international cooperation becomes evident in situations - where the effectiveness of physical protection in one State depends on the taking by other States also of adequate measures to deter and defeat hostile actions against nuclear

  6. Canada's Physical Activity Guide: examining print-based material for motivating physical activity in the workplace.

    Science.gov (United States)

    Plotnikoff, Ronald C; Todosijczuk, Ivan; Johnson, Steven T; Karunamuni, Nandini

    2012-01-01

    The authors conducted a secondary analysis on 202 adults from the Physical Activity Workplace Study. The aim of this analysis was to examine demographic characteristics associated with reading Canada's Physical Activity Guide (CPAG), being motivated by the guide, and whether participants in the Physical Activity Workplace Study who read the CPAG increased their physical activity levels over 1 year. Results revealed that less than 50% of participants read the full version of CPAG, and less than 10% were motivated by it. The CPAG also appears to be more appealing to and effective for women than for men. Although the CPAG had some influence in increasing mild physical activity levels in a workplace sample, there was also a decrease in physical activity levels among some members of the group. Overall, the effectiveness of CPAG was not substantial, and the findings of this analysis could help guide future targeted intervention materials and programs.

  7. MATERIAL SUPPLY AND MAGNETIC CONFIGURATION OF AN ACTIVE REGION FILAMENT

    Energy Technology Data Exchange (ETDEWEB)

    Zou, P.; Fang, C.; Chen, P. F.; Yang, K.; Hao, Q. [School of Astronomy and Space Science, Nanjing University, Nanjing 210023 (China); Cao, Wenda, E-mail: fangc@nju.edu.cn [Big Bear Solar Observatory, New Jersey Institute of Technology, 40386 North Shore Lane, Big Bear City, CA 92314 (United States)

    2016-11-10

    It is important to study the fine structures of solar filaments with high-resolution observations, since it can help us understand the magnetic and thermal structures of the filaments and their dynamics. In this paper, we study a newly formed filament located inside the active region NOAA 11762, which was observed by the 1.6 m New Solar Telescope at Big Bear Solar Observatory from 16:40:19 UT to 17:07:58 UT on 2013 June 5. As revealed by the H α filtergrams, cool material is seen to be injected into the filament spine with a speed of 5–10 km s{sup -1}. At the source of the injection, brightenings are identified in the chromosphere, which are accompanied by magnetic cancellation in the photosphere, implying the importance of magnetic reconnection in replenishing the filament with plasmas from the lower atmosphere. Counter-streamings are detected near one endpoint of the filament, with the plane-of-the-sky speed being 7–9 km s{sup -1} in the H α red-wing filtergrams and 9–25 km s{sup -1} in the blue-wing filtergrams. The observations are indicative that this active region filament is supported by a sheared arcade without magnetic dips, and the counter-streamings are due to unidirectional flows with alternative directions, rather than due to the longitudinal oscillations of filament threads as in many other filaments.

  8. Effect of computer mouse gain and visual demand on mouse clicking performance and muscle activation in a young and elderly group of experienced computer users

    DEFF Research Database (Denmark)

    Sandfeld, Jesper; Jensen, Bente R.

    2005-01-01

    and three levels of target size were used. All subjects demonstrated a reduced working speed and hit rate at the highest mouse gain (1:8) when the target size was small. The young group had an optimum at mouse gain 1:4. The elderly group was most sensitive to the combination of high mouse gain and small...

  9. ReflectoActive(trademark) Seals for Materials Control and Accountability

    International Nuclear Information System (INIS)

    Richardson, G.D.; Younkin, J.R.; Bell, Z.W.

    2002-01-01

    The ReflectoActive(trademark) Seals system, a continuously monitored fiber optic, active seal technology, provides real-time tamper indication for large arrays of storage containers. The system includes a PC running the RFAS software, an Immediate Detection Unit (IDU), an Optical Time Domain Reflectometer (OTDR), links of fiber optic cable, and the methods and devices used to attach the fiber optic cable to the containers. When a breach on any of the attached fiber optic cable loops occurs, the IDU immediately signals the connected computer to control the operations of an OTDR to seek the breach location. The ReflectoActive(trademark) Seals System can be adapted for various types of container closure designs and implemented in almost any container configuration. This automatic protection of valued assets can significantly decrease the time and money required for surveillance. The RFAS software is the multi-threaded, client-server application that monitors and controls the components of the system. The software administers the security measures such as a two-person rule as well as continuous event logging. Additionally the software's architecture provides a secure method by which local or remote clients monitor the system and perform administrative tasks. These features provide the user with a robust system to meet today's material control and accountability needs. A brief overview of the hardware, and different hardware configurations will be given. The architecture of the system software, and its benefits will then be discussed. Finally, the features to be implemented in future versions of the system will be presented

  10. Method and system for edge cladding of laser gain media

    Science.gov (United States)

    Bayramian, Andrew James; Caird, John Allyn; Schaffers, Kathleen Irene

    2014-03-25

    A gain medium operable to amplify light at a gain wavelength and having reduced transverse ASE includes an input surface and an output surface opposing the input surface. The gain medium also includes a central region including gain material and extending between the input surface and the output surface along a longitudinal optical axis of the gain medium. The gain medium further includes an edge cladding region surrounding the central region and extending between the input surface and the output surface along the longitudinal optical axis of the gain medium. The edge cladding region includes the gain material and a dopant operable to absorb light at the gain wavelength.

  11. Weight Gain during Pregnancy

    Science.gov (United States)

    ... Global Map Premature Birth Report Cards Careers Archives Pregnancy Before or between pregnancies Nutrition, weight & fitness Prenatal ... fitness > Weight gain during pregnancy Weight gain during pregnancy E-mail to a friend Please fill in ...

  12. Preventing Weight Gain

    Science.gov (United States)

    ... Local Programs Related Topics Diabetes Nutrition Preventing Weight Gain Language: English (US) Español (Spanish) Recommend on Facebook ... cancer. Choosing an Eating Plan to Prevent Weight Gain So, how do you choose a healthful eating ...

  13. Glass-crystalline materials for active waste incorporation

    International Nuclear Information System (INIS)

    Kulichenko, V.V.; Krylova, N.V.; Vlasov, V.I.; Polyakov, A.S.

    1979-01-01

    This paper presents the results of investigations into the possibility and conditions for using glass-crystalline materials for the incorporation of radionuclides. Materials of a cast pyroxene type that are obtained by smelting calcined wastes with acid blast furnace slags are described. A study was also made of materials of a basalt type prepared from wastes with and without alkali metal salt. Changes in the structure and properties of materials in the process of storage at different temperatures have been studied

  14. Creating Active Device Materials for Nanoelectronics Using Block Copolymer Lithography

    Directory of Open Access Journals (Sweden)

    Cian Cummins

    2017-09-01

    Full Text Available The prolonged and aggressive nature of scaling to augment the performance of silicon integrated circuits (ICs and the technical challenges and costs associated with this has led to the study of alternative materials that can use processing schemes analogous to semiconductor manufacturing. We examine the status of recent efforts to develop active device elements using nontraditional lithography in this article, with a specific focus on block copolymer (BCP feature patterning. An elegant route is demonstrated using directed self-assembly (DSA of BCPs for the fabrication of aligned tungsten trioxide (WO3 nanowires towards nanoelectronic device application. The strategy described avoids conventional lithography practices such as optical patterning as well as repeated etching and deposition protocols and opens up a new approach for device development. Nanoimprint lithography (NIL silsesquioxane (SSQ-based trenches were utilized in order to align a cylinder forming poly(styrene-block-poly(4-vinylpyridine (PS-b-P4VP BCP soft template. We outline WO3 nanowire fabrication using a spin-on process and the symmetric current-voltage characteristics of the resulting Ti/Au (5 nm/45 nm contacted WO3 nanowires. The results highlight the simplicity of a solution-based approach that allows creating active device elements and controlling the chemistry of specific self-assembling building blocks. The process enables one to dictate nanoscale chemistry with an unprecedented level of sophistication, forging the way for next-generation nanoelectronic devices. We lastly outline views and future research studies towards improving the current platform to achieve the desired device performance.

  15. Creating Active Device Materials for Nanoelectronics Using Block Copolymer Lithography.

    Science.gov (United States)

    Cummins, Cian; Bell, Alan P; Morris, Michael A

    2017-09-30

    The prolonged and aggressive nature of scaling to augment the performance of silicon integrated circuits (ICs) and the technical challenges and costs associated with this has led to the study of alternative materials that can use processing schemes analogous to semiconductor manufacturing. We examine the status of recent efforts to develop active device elements using nontraditional lithography in this article, with a specific focus on block copolymer (BCP) feature patterning. An elegant route is demonstrated using directed self-assembly (DSA) of BCPs for the fabrication of aligned tungsten trioxide (WO₃) nanowires towards nanoelectronic device application. The strategy described avoids conventional lithography practices such as optical patterning as well as repeated etching and deposition protocols and opens up a new approach for device development. Nanoimprint lithography (NIL) silsesquioxane (SSQ)-based trenches were utilized in order to align a cylinder forming poly(styrene)- block -poly(4-vinylpyridine) (PS- b -P4VP) BCP soft template. We outline WO₃ nanowire fabrication using a spin-on process and the symmetric current-voltage characteristics of the resulting Ti/Au (5 nm/45 nm) contacted WO₃ nanowires. The results highlight the simplicity of a solution-based approach that allows creating active device elements and controlling the chemistry of specific self-assembling building blocks. The process enables one to dictate nanoscale chemistry with an unprecedented level of sophistication, forging the way for next-generation nanoelectronic devices. We lastly outline views and future research studies towards improving the current platform to achieve the desired device performance.

  16. Molecularly imprinted hydrogels as functional active packaging materials.

    Science.gov (United States)

    Benito-Peña, Elena; González-Vallejo, Victoria; Rico-Yuste, Alberto; Barbosa-Pereira, Letricia; Cruz, José Manuel; Bilbao, Ainhoa; Alvarez-Lorenzo, Carmen; Moreno-Bondi, María Cruz

    2016-01-01

    This paper describes the synthesis of novel molecularly imprinted hydrogels (MIHs) for the natural antioxidant ferulic acid (FA), and their application as packaging materials to prevent lipid oxidation of butter. A library of MIHs was synthesized using a synthetic surrogate of FA, 3-(4-hydroxy-3-methoxyphenyl)propionic acid (HFA), as template molecule, ethyleneglycol dimethacrylate (EDMA) as cross-linker, and 1-allylpiperazine (1-ALPP) or 2-(dimethylamino)ethyl methacrylate (DMAEMA), in combination with 2-hydroxyethyl methacrylate (HEMA) as functional monomers, at different molar concentrations. The DMAEMA/HEMA-based MIHs showed the greatest FA loading capacity, while the 1-ALLP/HEMA-based polymers exhibited the highest imprinting effect. During cold storage, FA-loaded MIHs protected butter from oxidation and led to TBARs values that were approximately half those of butter stored without protection and 25% less than those recorded for butter covered with hydrogels without FA, potentially extending the shelf life of butter. Active packaging is a new field of application for MIHs with great potential in the food industry. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Activity-based Costing (ABC) and Activity-based Management(ABM)Implementation – Is This the Solution for Organizations to Gain Profitability?

    OpenAIRE

    Ildikó Réka CARDOS; Stefan PETE

    2011-01-01

    Adherents of ABC/ABM systems claimed traditional management accounting systems generated misleading costs in a contemporary, tumultuous, often changing business environment and implementing ABC/ABM would remedy this. That is why activity-based costing (ABC) and activity-based management (ABM) represents the symbol of improved competitiveness and efficiency in every organization.The purpose of this article – after analyzing the existing literature in the field – is to emphasize that new cost s...

  18. Adsorption of Safranin-T from wastewater using waste materials- activated carbon and activated rice husks.

    Science.gov (United States)

    Gupta, Vinod K; Mittal, Alok; Jain, Rajeev; Mathur, Megha; Sikarwar, Shalini

    2006-11-01

    Textile effluents are major industrial polluters because of high color content, about 15% unfixed dyes and salts. The present paper is aimed to investigate and develop cheap adsorption methods for color removal from wastewater using waste materials activated carbon and activated rice husk-as adsorbents. The method was employed for the removal of Safranin-T and the influence of various factors such as adsorbent dose, adsorbate concentration, particle size, temperature, contact time, and pH was studied. The adsorption of the dye over both the adsorbents was found to follow Langmuir and Freundlich adsorption isotherm models. Based on these models, different useful thermodynamic parameters have been evaluated for both the adsorption processes. The adsorption of Safranin-T over activated carbon and activated rice husks follows first-order kinetics and the rate constants for the adsorption processes decrease with increase in temperature.

  19. Acting to gain information

    Science.gov (United States)

    Rosenchein, Stanley J.; Burns, J. Brian; Chapman, David; Kaelbling, Leslie P.; Kahn, Philip; Nishihara, H. Keith; Turk, Matthew

    1993-01-01

    This report is concerned with agents that act to gain information. In previous work, we developed agent models combining qualitative modeling with real-time control. That work, however, focused primarily on actions that affect physical states of the environment. The current study extends that work by explicitly considering problems of active information-gathering and by exploring specialized aspects of information-gathering in computational perception, learning, and language. In our theoretical investigations, we analyzed agents into their perceptual and action components and identified these with elements of a state-machine model of control. The mathematical properties of each was developed in isolation and interactions were then studied. We considered the complexity dimension and the uncertainty dimension and related these to intelligent-agent design issues. We also explored active information gathering in visual processing. Working within the active vision paradigm, we developed a concept of 'minimal meaningful measurements' suitable for demand-driven vision. We then developed and tested an architecture for ongoing recognition and interpretation of visual information. In the area of information gathering through learning, we explored techniques for coping with combinatorial complexity. We also explored information gathering through explicit linguistic action by considering the nature of conversational rules, coordination, and situated communication behavior.

  20. Normal hematopoiesis and lack of β-catenin activation in osteoblasts of patients and mice harboring Lrp5 gain-of-function mutations.

    Science.gov (United States)

    Galán-Díez, Marta; Isa, Adiba; Ponzetti, Marco; Nielsen, Morten Frost; Kassem, Moustapha; Kousteni, Stavroula

    2016-03-01

    Osteoblasts are emerging regulators of myeloid malignancies since genetic alterations in them, such as constitutive activation of β-catenin, instigate their appearance. The LDL receptor-related protein 5 (LRP5), initially proposed to be a co-receptor for Wnt proteins, in fact favors bone formation by suppressing gut-serotonin synthesis. This function of Lrp5 occurring in the gut is independent of β-catenin activation in osteoblasts. However, it is unknown whether Lrp5 can act directly in osteoblast to influence other functions that require β-catenin signaling, particularly, the deregulation of hematopoiesis and leukemogenic properties of β-catenin activation in osteoblasts, that lead to development of acute myeloid leukemia (AML). Using mice with gain-of-function (GOF) Lrp5 alleles (Lrp5(A214V)) that recapitulate the human high bone mass (HBM) phenotype, as well as patients with the T253I HBM Lrp5 mutation, we show here that Lrp5 GOF mutations in both humans and mice do not activate β-catenin signaling in osteoblasts. Consistent with a lack of β-catenin activation in their osteoblasts, Lrp5(A214V) mice have normal trilinear hematopoiesis. In contrast to leukemic mice with constitutive activation of β-catenin in osteoblasts (Ctnnb1(CAosb)), accumulation of early myeloid progenitors, a characteristic of AML, myeloid-blasts in blood, and segmented neutrophils or dysplastic megakaryocytes in the bone marrow, are not observed in Lrp5(A214V) mice. Likewise, peripheral blood count analysis in HBM patients showed normal hematopoiesis, normal percentage of myeloid cells, and lack of anemia. We conclude that Lrp5 GOF mutations do not activate β-catenin signaling in osteoblasts. As a result, myeloid lineage differentiation is normal in HBM patients and mice. This article is part of a Special Issue entitled: Tumor Microenvironment Regulation of Cancer Cell Survival, Metastasis, Inflammation, and Immune Surveillance edited by Peter Ruvolo and Gregg L. Semenza. Published

  1. Relative contributions of energy expenditure on physical activity, body composition and weight gain to the evolution of impaired glucose tolerance to Frank diabetes

    International Nuclear Information System (INIS)

    Adeyemo, A.A.; Omotade, O.O.; Forrester, T.E.; Luke, A.; Rotimi, C.; Owoaje, E.T.

    2002-01-01

    The effect of obesity on glucose intolerance is a mixture of impact of body composition on glucose-insulin relationships as well as the modulation of this metabolism by physical activity. In this project, we seek to measure the energy expenditure on activity, the rate of weight gain and changes in body composition in a free-living population, and to relate these variables to changes in glucose tolerance and insulin sensitivity. We have enrolled a cohort of 280 adults in Idikan, a poor urban community in lbadan, Nigeria, selected by simple random sampling from a population database. In this communication, we report characteristics of the study cohort, findings on evaluation of a physical activity questionnaire and changes in body size, body composition and measures of insulin resistance over a one-year period. Mean age of the men is 49.7 (SD 12.7) years and of the women 44.7 (SD 10.7) years. Mean fasting blood glucose was 4.57 (SD 4.75) mmol/L among men and 3.54 (SD 1.02) mmol/L among women. The modified HIP physical activity (PA) questionnaire was evaluated in a subset of participants for whom scale reliability coefficients of 0.57 and 0.33 were obtained for the occupational and leisure scales of HIP respectively. Two-week test-retest intraclass correlation coefficient was 0.53. On validation against doubly-labelled water measurements, the HIP occupational score showed a positive correlation (r=0.37, p=0.01) with activity energy expenditure per kg body weight (AEE per kg) and a similar correlation of 0. 37 with physical activity level (PAL). Thus, the HIP occupational scale showed adequate consistency, good test-retest reliability and good correlations with measures of physical activity by doubly-labelled water. Over a one-year follow-up period, the participants showed increases in weight, BMI, waist circumferences, fat mass, fasting insulin and insulin-to-glucose ratio. However, HOMA-IR did not significantly change. Overweight increased from 21.3% to 23.9% while

  2. Relative contributions of energy expenditure on physical activity, body composition and weight gain to the evolution of impaired glucose tolerance to Frank diabetes

    Energy Technology Data Exchange (ETDEWEB)

    Adeyemo, A A [Department of Paediatrics and Institute of Child Health, College of Medicine, University of Ibadan, University College Hospital, Ibadan (Nigeria); Omotade, O O [Institute of Child Health, College of Medicine, University of Ibadan, Ibadan (Nigeria); Forrester, T E [Tropical Metabolism Research Institute, University of the West Indies, Kingston (Jamaica); Luke, A [Department of Preventive Medicine and Epidemiology, Loyola University, Chicago (United States); Rotimi, C [National Human Genome Center, Howard University, Washington, DC (United States); Owoaje, E T [Department of Community Medicine, College of Medicine, University of Ibadan (Nigeria)

    2002-07-01

    The effect of obesity on glucose intolerance is a mixture of impact of body composition on glucose-insulin relationships as well as the modulation of this metabolism by physical activity. In this project, we seek to measure the energy expenditure on activity, the rate of weight gain and changes in body composition in a free-living population, and to relate these variables to changes in glucose tolerance and insulin sensitivity. We have enrolled a cohort of 280 adults in Idikan, a poor urban community in lbadan, Nigeria, selected by simple random sampling from a population database. In this communication, we report characteristics of the study cohort, findings on evaluation of a physical activity questionnaire and changes in body size, body composition and measures of insulin resistance over a one-year period. Mean age of the men is 49.7 (SD 12.7) years and of the women 44.7 (SD 10.7) years. Mean fasting blood glucose was 4.57 (SD 4.75) mmol/L among men and 3.54 (SD 1.02) mmol/L among women. The modified HIP physical activity (PA) questionnaire was evaluated in a subset of participants for whom scale reliability coefficients of 0.57 and 0.33 were obtained for the occupational and leisure scales of HIP respectively. Two-week test-retest intraclass correlation coefficient was 0.53. On validation against doubly-labelled water measurements, the HIP occupational score showed a positive correlation (r=0.37, p=0.01) with activity energy expenditure per kg body weight (AEE per kg) and a similar correlation of 0. 37 with physical activity level (PAL). Thus, the HIP occupational scale showed adequate consistency, good test-retest reliability and good correlations with measures of physical activity by doubly-labelled water. Over a one-year follow-up period, the participants showed increases in weight, BMI, waist circumferences, fat mass, fasting insulin and insulin-to-glucose ratio. However, HOMA-IR did not significantly change. Overweight increased from 21.3% to 23.9% while

  3. Activity-based Costing (ABC and Activity-based Management(ABMImplementation – Is This the Solution for Organizations to Gain Profitability?

    Directory of Open Access Journals (Sweden)

    Ildikó Réka CARDOS

    2011-06-01

    Full Text Available Adherents of ABC/ABM systems claimed traditional management accounting systems generated misleading costs in a contemporary, tumultuous, often changing business environment and implementing ABC/ABM would remedy this. That is why activity-based costing (ABC and activity-based management (ABM represents the symbol of improved competitiveness and efficiency in every organization.The purpose of this article – after analyzing the existing literature in the field – is to emphasize that new cost systems such as ABC and ABM could be a strong couple that assures competitiveness and efficiency for each company. Another objective is to present that, besides its disadvantages, firms implement the ABC/ABM system because it permits better tracing of costs to objects, superior allocation of overheads to cost objects, financial and non-financial analysis and measures useful to managers and management accountants in the decision-making process.

  4. The Active Model: a calibration of material intent

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette; Tamke, Martin

    2012-01-01

    created it. This definition suggests structural characteristics that are perhaps not immediately obvious when implemented within architectural models. It opens the idea that materiality might persist into the digital environment, as well as the digital lingering within the material. It implies questions...

  5. Mould growth on building materials under low water activities

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Holm, G.; Uttrup, L.P.

    2004-01-01

    The influence of relative humidity (RH) and temperature on growth and metabolism of eight microfungi on 21 different types of building material was investigated. The fungi were applied as a dry mixture to the materials, which were incubated at 5degreesC, 10degreesC, 20degreesC and 25degrees...... growth at RH > 90%, although 95% RH was needed to yield chemically detectable quantities of biomass. Almost exclusively only Penicillium, Aspergillus and Eurotium (contaminant) species grew on the materials. Production of secondary metabolites and mycotoxins decreased with humidity and the quantities...

  6. Computational micromechanics of wind blade materials: recent activities at the Materials Research Division, Risoe DTU

    Energy Technology Data Exchange (ETDEWEB)

    Mishnaevsky Jr., L.; Broendsted, P.; Qing, H.; Wang, H.; Soerensen, Bent F. (Technical Univ. of Denmark, Riso National Lab. for Sustainable Energy. Materials Research Div., Roskilde (Denmark)); OEstergaard, R.C. (LM Wind Power Blades, Composite Mechanics, Roskilde (Denmark))

    2010-10-22

    Recent research works in the area of 3D computational microstructural modelling, virtual testing and numerical optimization of wind blade materials, carried out at the Materials Research Division, Rise DTU (Programme Composites and Materials Mechanics) are summarized. The works presented here have been carried out in the framework of several research projects: EU FP6 Upwind, Danida project 'Development of wind energy technologies in Nepal' and SinoDanish project '3D Virtual Testing of composites for wind energy applications' as well as the Framework Program 'Interface design of composite materials' and recently established Danish Centre for Composite Structures and Materials for Wind Turbines. Different groups of materials, which are used or have a potential for use for the wind turbine blades, are modelled with the use of the methods of the computational micromechanics, in particular: (1) glass and carbon fiber reinforced polymer composites used in the large wind turbine blades, (2) different sorts of timber, used in small wind turbines (first of all, in developing countries) and (3) nanoparticle reinforced polymer matrix composites (which have a potential to be used as components for future high strength wind blades). On the basis of the developed 3D microstructural finite element models of these materials, we analyzed the effect of their microstructures on damage resistance, strength and stiffness. The methods of the 3D model design and results of the simulations are discussed in this paper. (Author)

  7. Biomimetic Polyaminoacids as Precursors for Optical-Active Intelligent Materials

    National Research Council Canada - National Science Library

    Popova, G

    2003-01-01

    ...; function on nanoscale; stimula-responsive study; intelligent materials formation. Modified polyglutamic acid with dyes regular set possesses specific ability to self-assembly with cooperative rearrangement under outer temperature...

  8. Method for monitoring drilling materials for gamma ray activity

    International Nuclear Information System (INIS)

    Smith, H.D. Jr.; Arnold, D.M.; Schultz, W.E.

    1985-01-01

    In the preferred and illustrated embodiment taught herein, method steps for monitoring of raw materials to be used in drilling mud are disclosed. The materials are monitored for radioactivity. Procedures for taking such measurements are disclosed, and the extent of gamma radioactivity in the raw materials used in drilling mud is, determined. This is correlated to the increased radiation attributable to mud made from these materials and the effect the mud would have on gamma ray measuring logs. An alternate procedure for testing drilling mud, typically at the well site, is also disclosed. The method detects mud radioactivity from any additives including barite, potassium chloride, well cuttings or others. Excessive background levels due to mud gamma radioactivity in a well may very well mask the data obtained by various logging procedures dependent on gamma radiation. Procedures are also described for either rejecting mud which is too radioactive or correcting the log measurements for mud effects

  9. Alanine-scanning mutagenesis of human signal transducer and activator of transcription 1 to estimate loss- or gain-of-function variants.

    Science.gov (United States)

    Kagawa, Reiko; Fujiki, Ryoji; Tsumura, Miyuki; Sakata, Sonoko; Nishimura, Shiho; Itan, Yuval; Kong, Xiao-Fei; Kato, Zenichiro; Ohnishi, Hidenori; Hirata, Osamu; Saito, Satoshi; Ikeda, Maiko; El Baghdadi, Jamila; Bousfiha, Aziz; Fujiwara, Kaori; Oleastro, Matias; Yancoski, Judith; Perez, Laura; Danielian, Silvia; Ailal, Fatima; Takada, Hidetoshi; Hara, Toshiro; Puel, Anne; Boisson-Dupuis, Stéphanie; Bustamante, Jacinta; Casanova, Jean-Laurent; Ohara, Osamu; Okada, Satoshi; Kobayashi, Masao

    2017-07-01

    Germline heterozygous mutations in human signal transducer and activator of transcription 1 (STAT1) can cause loss of function (LOF), as in patients with Mendelian susceptibility to mycobacterial diseases, or gain of function (GOF), as in patients with chronic mucocutaneous candidiasis. LOF and GOF mutations are equally rare and can affect the same domains of STAT1, especially the coiled-coil domain (CCD) and DNA-binding domain (DBD). Moreover, 6% of patients with chronic mucocutaneous candidiasis with a GOF STAT1 mutation have mycobacterial disease, obscuring the functional significance of the identified STAT1 mutations. Current computational approaches, such as combined annotation-dependent depletion, do not distinguish LOF and GOF variants. We estimated variations in the CCD/DBD of STAT1. We mutagenized 342 individual wild-type amino acids in the CCD/DBD (45.6% of full-length STAT1) to alanine and tested the mutants for STAT1 transcriptional activity. Of these 342 mutants, 201 were neutral, 30 were LOF, and 111 were GOF mutations in a luciferase assay. This assay system correctly estimated all previously reported LOF mutations (100%) and slightly fewer GOF mutations (78.1%) in the CCD/DBD of STAT1. We found that GOF alanine mutants occurred at the interface of the antiparallel STAT1 dimer, suggesting that they destabilize this dimer. This assay also precisely predicted the effect of 2 hypomorphic and dominant negative mutations, E157K and G250E, in the CCD of STAT1 that we found in 2 unrelated patients with Mendelian susceptibility to mycobacterial diseases. The systematic alanine-scanning assay is a useful tool to estimate the GOF or LOF status and the effect of heterozygous missense mutations in STAT1 identified in patients with severe infectious diseases, including mycobacterial and fungal diseases. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  10. Ciliary neurotrophic factor activates leptin-like pathways and reduces body fat, without cachexia or rebound weight gain, even in leptin-resistant obesity.

    Science.gov (United States)

    Lambert, P D; Anderson, K D; Sleeman, M W; Wong, V; Tan, J; Hijarunguru, A; Corcoran, T L; Murray, J D; Thabet, K E; Yancopoulos, G D; Wiegand, S J

    2001-04-10

    Ciliary Neurotrophic Factor (CNTF) was first characterized as a trophic factor for motor neurons in the ciliary ganglion and spinal cord, leading to its evaluation in humans suffering from motor neuron disease. In these trials, CNTF caused unexpected and substantial weight loss, raising concerns that it might produce cachectic-like effects. Countering this possibility was the suggestion that CNTF was working via a leptin-like mechanism to cause weight loss, based on the findings that CNTF acts via receptors that are not only related to leptin receptors, but also similarly distributed within hypothalamic nuclei involved in feeding. However, although CNTF mimics the ability of leptin to cause fat loss in mice that are obese because of genetic deficiency of leptin (ob/ob mice), CNTF is also effective in diet-induced obesity models that are more representative of human obesity, and which are resistant to leptin. This discordance again raised the possibility that CNTF might be acting via nonleptin pathways, perhaps more analogous to those activated by cachectic cytokines. Arguing strongly against this possibility, we now show that CNTF can activate hypothalamic leptin-like pathways in diet-induced obesity models unresponsive to leptin, that CNTF improves prediabetic parameters in these models, and that CNTF acts very differently than the prototypical cachectic cytokine, IL-1. Further analyses of hypothalamic signaling reveals that CNTF can suppress food intake without triggering hunger signals or associated stress responses that are otherwise associated with food deprivation; thus, unlike forced dieting, cessation of CNTF treatment does not result in binge overeating and immediate rebound weight gain.

  11. Activities of the years 1985/86 Materials Department

    International Nuclear Information System (INIS)

    1986-01-01

    The Materials Department of the National Atomic Energy Commission gives a description of the research done during the period 1985/1986 in the following fields; corrosion and transport of matter, transport phenomena, phase solidification and transformation, mechanical properties, theory of the materials behaviour, and special techniques development. Furthermore it is outlined the rendering of services and the advice given to the nuclear power plants and other institutions. Finally a list of publications, courses, seminars, lectures and presentation to congresses are included. (M.E.L.) [es

  12. Thermosetting materials from the radiation-modified polymer compositions, 2. Development of adhesion-active and thermostable thermosetting materials

    International Nuclear Information System (INIS)

    Kalkis, V.; Maksimovs, R.D.; Zicans, J.; Bocoka, T.; Revjakins, O.

    1999-01-01

    Methods that improve the adhesion and thermal stability of the thermosetting materials are considered. Experimental studies of the blends composed of polyethylene, ethylene-propylene-diene copolymer (with characteristic specific for rubbers) and mesomorphic copolyesters, using rheological, spectrometric, and thermomechanical methods, have shown that radiation modification improves the adhesion and deformation properties as well as thermal stability of these blends. Therefore, materials of such system can be successfully used, e.g., as elastic and adhesion-active thermosetting materials at temperature above 473 K. (author)

  13. Production and characterization of activated carbon using indigenous waste materials

    International Nuclear Information System (INIS)

    Shahid, M.; Ibrahim, F.

    2011-01-01

    Activated carbon was produced from shisham wood and coconut shell through chemical activation, using phosphoric acid and low temperature carbonization. Proximate analysis and characterization of the product were carried out and Brunauer Emmett Teller (BET) surface area, total ash content, moisture content, pH value and iodine number were determined. The product characteristics were well comparable with those of the commercially available activated carbon. (author)

  14. Computer design of porous active materials at different dimensional scales

    Science.gov (United States)

    Nasedkin, Andrey

    2017-12-01

    The paper presents a mathematical and computer modeling of effective properties of porous piezoelectric materials of three types: with ordinary porosity, with metallized pore surfaces, and with nanoscale porosity structure. The described integrated approach includes the effective moduli method of composite mechanics, simulation of representative volumes, and finite element method.

  15. Solar Energy Educational Material, Activities and Science Projects

    Science.gov (United States)

    dropdown arrow Site Map A-Z Index Menu Synopsis Solar Energy Educational Materials Solar with glasses " ;The sun has produced energy for billions of years. Solar energy is the solar radiation that reaches the earth. Solar energy can be converted directly or indirectly into other forms of energy, such as

  16. Fluorine determinations in biological materials by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Demiralp, R.; Guinn, V.P.; Becker, D.A.

    1992-01-01

    Exploratory studies were carried out at the University of California, Irvine on several freeze-dried human diet materials and on two freeze-dried vegetation materials - all prospective reference materials. The University of California, Irvine equipment includes a 250-kW TRIGA Mark 1 reactor, 2.5 x 10 12 n/cm 2 ·s thermal flux, 3-s sample transfer time, and a typical 18% Ge(Li)/4,096-channel gamma-ray spectrometer with a detector resolution of 3.3 keV at 1,332 keV. In these exploratory studies, it was found that it was not feasible to measure fluorine with adequate precision or accuracy at fluorine concentrations much less than ∼100 ppm. These initial studies, however, defined the magnitudes of the various difficulties. One good outcome of these studies was the demonstration that the otherwise excellent Teflon-mill brittle-fracture method for homogenizing freeze-dried biological samples was not suitable if fluorine was to be determined. Abrasion of the Teflon increased the fluorine content of a human diet sample about sevenfold (compared with similar treatment of the same material in an all-titanium mill)

  17. Materials for Consideration in Standardized Canister Design Activities.

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Charles R.; Ilgen, Anastasia Gennadyevna; Enos, David George; Teich-McGoldrick, Stephanie; Hardin, Ernest

    2014-10-01

    This document identifies materials and material mitigation processes that might be used in new designs for standardized canisters for storage, transportation, and disposal of spent nuclear fuel. It also addresses potential corrosion issues with existing dual-purpose canisters (DPCs) that could be addressed in new canister designs. The major potential corrosion risk during storage is stress corrosion cracking of the weld regions on the 304 SS/316 SS canister shell due to deliquescence of chloride salts on the surface. Two approaches are proposed to alleviate this potential risk. First, the existing canister materials (304 and 316 SS) could be used, but the welds mitigated to relieve residual stresses and/or sensitization. Alternatively, more corrosion-resistant steels such as super-austenitic or duplex stainless steels, could be used. Experimental testing is needed to verify that these alternatives would successfully reduce the risk of stress corrosion cracking during fuel storage. For disposal in a geologic repository, the canister will be enclosed in a corrosion-resistant or corrosion-allowance overpack that will provide barrier capability and mechanical strength. The canister shell will no longer have a barrier function and its containment integrity can be ignored. The basket and neutron absorbers within the canister have the important role of limiting the possibility of post-closure criticality. The time period for corrosion is much longer in the post-closure period, and one major unanswered question is whether the basket materials will corrode slowly enough to maintain structural integrity for at least 10,000 years. Whereas there is extensive literature on stainless steels, this evaluation recommends testing of 304 and 316 SS, and more corrosion-resistant steels such as super-austenitic, duplex, and super-duplex stainless steels, at repository-relevant physical and chemical conditions. Both general and localized corrosion testing methods would be used to

  18. Antidepressants and Weight Gain

    Science.gov (United States)

    ... 2015;37:46. Blumenthal SR, et al. An electronic health records study of long-term weight gain following antidepressant ... your agreement to the Terms and Conditions and Privacy Policy linked below. Terms and Conditions Privacy Policy ...

  19. Weight gain - unintentional

    Science.gov (United States)

    ... diabetes Hormone changes or medical problems can also cause unintentional weight gain. This may be due to: Cushing syndrome Underactive thyroid, or low thyroid (hypothyroidism) Polycystic ovary syndrome Menopause Pregnancy Bloating, or swelling ...

  20. Progress in the US program to develop low-activation structural materials for fusion

    International Nuclear Information System (INIS)

    Kurtz, R.J.; Jones, R.H.; Bloom, E.E.; Rowcliffe, A.F.; Smith, D.L.; Odette, G.R.; Wiffen, F.W.

    1999-01-01

    It has long been recognized that attainment of the safety and environmental potential of fusion energy requires the successful development of low-activation materials for the first wall, blanket and other high heat flux structural components. Only a limited number of materials potentially possess the physical, mechanical and low-activation characteristics required for this application. The current US structural materials research effort is focused on three candidate materials: advanced ferritic steels, vanadium alloys, and silicon carbide composites. Recent progress has been made in understanding the response of these materials to neutron irradiation. (author)

  1. Progress in the U.S. program to develop low-activation structural materials for fusion

    International Nuclear Information System (INIS)

    Kurtz, R.J.; Jones, R.H.; Bloom, E.E.; Rowcliffe, A.F.; Smith, D.L.; Odette, G.R.; Wiffen, F.W.

    2001-01-01

    It has long been recognized that attainment of the safety and environmental potential of fusion energy requires the successful development of low-activation materials for the first wall, blanket and other high heat flux structural components. Only a limited number of materials potentially possess the physical, mechanical and low-activation characteristics required for this application. The current U.S. structural materials research effort is focused on three candidate materials: advanced ferritic steels, vanadium alloys, and silicon carbide composites. Recent progress has been made in understanding the response of these materials to neutron irradiation. (author)

  2. Continuous-wave infrared optical gain and amplified spontaneous emission at ultralow threshold by colloidal HgTe quantum dots

    NARCIS (Netherlands)

    Geiregat, Pieter; Houtepen, Arjan J.; Sagar, Laxmi Kishore; Infante, Ivan; Zapata, Felipe; Grigel, Valeriia; Allan, Guy; Delerue, Christophe; Van Thourhout, Dries; Hens, Zeger

    2017-01-01

    Colloidal quantum dots (QDs) raise more and more interest as solution-processable and tunable optical gain materials. However, especially for infrared active QDs, optical gain remains inefficient. Since stimulated emission involves multifold degenerate band-edge states, population inversion can be

  3. Continuous-wave infrared optical gain and amplified spontaneous emission at ultralow threshold by colloidal HgTe quantum dots

    NARCIS (Netherlands)

    Geiregat, P.A.; Houtepen, A.J.; Sagar, Laxmi Kishore; Infante, Ivan; Zapata, Felipe; Grigel, Valeriia; Allan, Guy; Delerue, Christophe; Van Thourhout, Dries; Hens, Zeger

    2018-01-01

    Colloidal quantum dots (QDs) raise more and more interest as solution-processable and tunable optical gain materials. However, especially for infrared active QDs, optical gain remains inefficient. Since stimulated emission involves multifold degenerate band-edge states, population inversion can

  4. Activity measurement and effective dose modelling of natural radionuclides in building material

    International Nuclear Information System (INIS)

    Maringer, F.J.; Baumgartner, A.; Rechberger, F.; Seidel, C.; Stietka, M.

    2013-01-01

    In this paper the assessment of natural radionuclides' activity concentration in building materials, calibration requirements and related indoor exposure dose models is presented. Particular attention is turned to specific improvements in low-level gamma-ray spectrometry to determine the activity concentration of necessary natural radionuclides in building materials with adequate measurement uncertainties. Different approaches for the modelling of the effective dose indoor due to external radiation resulted from natural radionuclides in building material and results of actual building material assessments are shown. - Highlights: • Dose models for indoor radiation exposure due to natural radionuclides in building materials. • Strategies and methods in radionuclide metrology, activity measurement and dose modelling. • Selection of appropriate parameters in radiation protection standards for building materials. • Scientific-based limitations of indoor exposure due to natural radionuclides in building materials

  5. Bayesian Regression of Thermodynamic Models of Redox Active Materials

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, Katherine [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    Finding a suitable functional redox material is a critical challenge to achieving scalable, economically viable technologies for storing concentrated solar energy in the form of a defected oxide. Demonstrating e ectiveness for thermal storage or solar fuel is largely accomplished by using a thermodynamic model derived from experimental data. The purpose of this project is to test the accuracy of our regression model on representative data sets. Determining the accuracy of the model includes parameter tting the model to the data, comparing the model using di erent numbers of param- eters, and analyzing the entropy and enthalpy calculated from the model. Three data sets were considered in this project: two demonstrating materials for solar fuels by wa- ter splitting and the other of a material for thermal storage. Using Bayesian Inference and Markov Chain Monte Carlo (MCMC), parameter estimation was preformed on the three data sets. Good results were achieved, except some there was some deviations on the edges of the data input ranges. The evidence values were then calculated in a variety of ways and used to compare models with di erent number of parameters. It was believed that at least one of the parameters was unnecessary and comparing evidence values demonstrated that the parameter was need on one data set and not signi cantly helpful on another. The entropy was calculated by taking the derivative in one variable and integrating over another. and its uncertainty was also calculated by evaluating the entropy over multiple MCMC samples. Afterwards, all the parts were written up as a tutorial for the Uncertainty Quanti cation Toolkit (UQTk).

  6. ACFA - a versatile activation code for coolant and structural materials

    International Nuclear Information System (INIS)

    Brockmann, H.; Ohlig, U.

    1983-09-01

    The ACFA code calculates the neutron-induced activation, afterheat, transmutation, gas production, biological hazard potential, and activation gamma ray spectra in the components of a nuclear system. The quantities of interest may be computed by spatial interval and zone or only by zone of the system considered. To calculate the transmutation coefficients for the neutron-induced reactions the code uses multigroup activation cross sections and space-dependent multigroup neutron fluxes in one- or two-dimensional geometry. The neutron reaction types incorporated in the code are: (n,n'), (n,2n), (n,γ), (n,p), (n,α), (n,n'p), (n,n'α)sub(,) (n,t), (n,3n), (n,He-3), (n,d), and (n,n'd) considering both reactions to the ground state and to isomeric states. The code uses a variable dimensioning technique to adapt the core data storage requirements to the particular problem considered and uses the FIDO input system to read the input data. The numerical methods for establishing and solving the decay chain equations are taken from the ORIGEN code. To test the ACFA code and the nuclear data libraries used, the activation, composition change, and gas production in the first wall of the UWMAK-I fusion reactor are calculated. The results of the activation calculation are compared with earlier results of the University of Wisconsin Fusion Study Group. (orig.)

  7. Bioreactor activated graft material for early implant fixation in bone

    DEFF Research Database (Denmark)

    Snoek Henriksen, Susan; Ding, Ming; Overgaard, Søren

    2011-01-01

    from the iliac crest. For both groups, mononuclear cells were isolated, and injected into a perfusion bioreactor (Millenium Biologix AG, Switzerland). Scaffold granules (Ø~900-1500 µm, ~88% porosity) in group 1, consisted of hydroxyapatite (HA, 70%) with β-tricalcium-phosphate (β-TCP, 30%) (Danish....... The superficial part was used for mechanical testing and micro-CT scanning, and the profound part for histomorphometry. Push-out tests were performed on an 858 Bionix MTS hydraulic materials testing machine (MTS Systems Corporation, USA). Shear mechanical properties between implant and newly generated bone were...

  8. Removal of blue indigo and cadmium present in aqueous solutions using a modified zeolitic material and an activated carbonaceous material

    International Nuclear Information System (INIS)

    Gutierrez S, E. E.

    2011-01-01

    In the last years the use of water has been increased substantially, it has been also altered its quality as a result of human activities such as mining, industrial activities and others. Water pollution caused by dyes and heavy metals has adverse effects on the environment, since both pollutants are very persisten even after conventional treatments. Denim blue and cadmium are not biodegradable. There is a growing interest in finding new, efficient and low cost alternative materials to remove such pollutants from the aqueous medium. The purpose of this work was to evaluate a modified zeolitic tuff and an activated carbonaceous material obtained from the pyrolysis of sewage sludge for the removal of denim blue and cadmium. The zeolitic material was modified with Na + and Fe 3+ solutions to improve its sorption properties for the removal of cadmium and denim blue, respectively. Carbonaceous material was treated with 10% HCl solution to remove ashes. Both materials were characterized by scanning electron microscopy and elemental analysis (EDS), specific surface areas (Bet), thermogravimetric analysis, infrared spectroscopy and X-ray diffraction. Simultaneously, the denim blue dye was characterized by infrared spectroscopy and its pKa value was determined, these data allowed the determination of its chemical properties and its acid-base behavior in solution. In the content of this work the term indigo blue was changed by denim blue, as it corresponds to the commercial name of the dye. To assess the sorption capacity of sorbents, the sorption kinetics and sorption isotherms in batch system were determined; the results were fitted to mathematical models such as the pseudo-first order, pseudo second order and second order to describe the sorption kinetics and the Langmuir, Freundlich and Langmuir-Freundlich isotherms to describe sorption processes. The results show that the most efficient material to remove denim blue from aqueous solutions is the carbonaceous material

  9. Graded territories: Towards the design, specification and simulation of materially graded bending active structures

    DEFF Research Database (Denmark)

    Nicholas, Paul; Tamke, Martin; Ramsgaard Thomsen, Mette

    2012-01-01

    these structures, the property of bending is activated and varied through bespoke material means so as to match a desired form. Within the architectural design process, formal control depends upon design approaches for material specification and simulation that consider behavior at the level of the material...... element as well as the structure. We describe an evolving approach to material specification and simulation, and highlight the digital and material considerations that frame the process.......The ability to make materials with bespoke behavior affords new perspectives on incorporating material properties within the design process not available through natural materials. This paper reports the design and assembly of two bending-active, fibre-reinforced composite structures. Within...

  10. ACTIVATED CARBONS FROM VEGETAL RAW MATERIALS TO SOLVE ENVIRONMENTAL PROBLEMS

    Directory of Open Access Journals (Sweden)

    Viktor Mukhin

    2014-06-01

    Full Text Available Technologies for active carbons obtaining from vegetable byproducts such as straw, nut shells, fruit stones, sawdust, hydrolysis products of corn cobs and sunflower husks have been developed. The physico-chemical characteristics, structural parameters and sorption characteristics of obtained active carbons were determined. The ability of carbonaceous adsorbents for detoxification of soil against pesticides, purification of surface waters and for removal of organic pollutants from wastewaters has been evaluated. The obtained results reveal the effectiveness of their use in a number of environmental technologies.

  11. Use of neutron activation in dietary reference material analysis

    Energy Technology Data Exchange (ETDEWEB)

    Woittiez, J R.W.; Iyengar, G V

    1988-12-01

    Results for a number of trace elements in a total human diet material (USDIET-1), obtained by the application of both INAA and RNAA are presented. Several dietary reference materials such as NBS SRM 1577A, and BCR CRM Single Cell Protein were also analyzed, and these results are also given. Combining measurements on short and long lived radionuclides, the INAA approach is useful for the determination of about 20 elements. In order to expand the elemental coverage or improve detection limits, RNAA was also explored in two modes: separation of radionuclides using organic ion exchange resins and the use of hydrated manganese dioxide. This combination is applicable to 15 trace elements. For example, using RNAA, the following results were obtained for USDIET-1: Cd=31.8, Mo=280, Cr=71, Ag=4, As=117 and Sb=9.4 ..mu..g/kg. In the INAA mode, special attention was given to Al, F and Se. The F content of USDIET-1 was found to be 840 mg/kg, a rather high value, resulting from handling USDIET-1 by Teflon tools. By applying INAA and RNAA under two different laboratory conditions, it has been demonstrated that, even for the so-called difficult to determine elements like Cr, As or Mo, consistent results can be obtained. Thus, NAA promises to be a strong tool for human nutritional studies.

  12. Rationalization of activation energies for creep of dispersion strengthened aluminium materials

    International Nuclear Information System (INIS)

    Carreno, F.; Ruano, O. A.

    2001-01-01

    The high apparent activation energies for creep of various aluminum dispersion strengthened materials have been analyzed. A direct relationship between the activation energies and stress exponents for every material has been observed. The values of the Q a p/n a p ratios group around some constant values, Q m , which depend solely on the deformation mechanism. Therefore, Q m establishes an easy, fast and reliable criterion to determine the underlying creep deformation mechanism of any reinforced materials. (Author) 18 refs

  13. Polyoxometalate active charge-transfer material for mediated redox flow battery

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Travis Mark; Hudak, Nicholas; Staiger, Chad; Pratt, Harry

    2017-01-17

    Redox flow batteries including a half-cell electrode chamber coupled to a current collecting electrode are disclosed herein. In a general embodiment, a separator is coupled to the half-cell electrode chamber. The half-cell electrode chamber comprises a first redox-active mediator and a second redox-active mediator. The first redox-active mediator and the second redox-active mediator are circulated through the half-cell electrode chamber into an external container. The container includes an active charge-transfer material. The active charge-transfer material has a redox potential between a redox potential of the first redox-active mediator and a redox potential of the second redox-active mediator. The active charge-transfer material is a polyoxometalate or derivative thereof. The redox flow battery may be particularly useful in energy storage solutions for renewable energy sources and for providing sustained power to an electrical grid.

  14. Trends in Catalytic Activity for SOFC Anode materials

    DEFF Research Database (Denmark)

    Rossmeisl, Jan; Bessler, W. G.

    2008-01-01

    that oxygen spillover, where adsorbed oxygen is a key intermediate, is the dominant reaction pathway under the conditions used in the experiments. In this way the activity is linked directly to the microscopic binding affinities of reaction intermediates, providing a new understanding of the anode reaction...

  15. Disseminated Tuberculosis and Chronic Mucocutaneous Candidiasis in a Patient with a Gain-of-Function Mutation in Signal Transduction and Activator of Transcription 1

    Directory of Open Access Journals (Sweden)

    Sigifredo Pedraza-Sánchez

    2017-12-01

    Full Text Available In humans, recessive loss-of-function mutations in STAT1 are associated with mycobacterial and viral infections, whereas gain-of-function (GOF mutations in STAT1 are associated with a type of primary immunodeficiency related mainly, but not exclusively, to chronic mucocutaneous candidiasis (CMC. We studied and established a molecular diagnosis in a pediatric patient with mycobacterial infections, associated with CMC. The patient, daughter of a non-consanguineous mestizo Mexican family, had axillary adenitis secondary to BCG vaccination and was cured with resection of the abscess at 1-year old. At the age of 4 years, she had a supraclavicular abscess with acid-fast-staining bacilli identified in the soft tissue and bone, with clinical signs of disseminated infection and a positive Gene-X-pert test, which responded to anti-mycobacterial drugs. Laboratory tests of the IL-12/interferon gamma (IFN-γ circuit showed a higher production of IL-12p70 in the whole blood from the patient compared to healthy controls, when stimulated with BCG and BCG + IFN-γ. The whole blood of the patient produced 35% less IFN-γ compared to controls assessed by ELISA and flow cytometry, but IL-17 producing T cells from patient were almost absent in PBMC stimulated with PMA plus ionomycin. Signal transduction and activator of transcription 1 (STAT1 was hyperphosphorylated at tyrosine 701 in response to IFN-γ and -α, as demonstrated by flow cytometry and Western blotting in fresh blood mononuclear cells and in Epstein-Barr virus lymphoblastoid cell lines (EBV-LCLs; phosphorylation of STAT1 in EBV-LCLs from the patient was resistant to inhibition by staurosporine but sensitive to ruxolitinib, a Jak phosphorylation inhibitor. Genomic DNA sequencing showed a de novo mutation in STAT1 in cells from the patient, absent in her parents and brother; a known T385M missense mutation in the DNA-binding domain of the transcription factor was identified, and it is a GOF

  16. Digital active material processing platform effort (DAMPER), SBIR phase 2

    Science.gov (United States)

    Blackburn, John; Smith, Dennis

    1992-11-01

    Applied Technology Associates, Inc., (ATA) has demonstrated that inertial actuation can be employed effectively in digital, active vibration isolation systems. Inertial actuation involves the use of momentum exchange to produce corrective forces which act directly on the payload being actively isolated. In a typical active vibration isolation system, accelerometers are used to measure the inertial motion of the payload. The signals from the accelerometers are then used to calculate the corrective forces required to counteract, or 'cancel out' the payload motion. Active vibration isolation is common technology, but the use of inertial actuation in such systems is novel, and is the focus of the DAMPER project. A May 1991 report was completed which documented the successful demonstration of inertial actuation, employed in the control of vibration in a single axis. In the 1 degree-of-freedom (1DOF) experiment a set of air bearing rails was used to suspend the payload, simulating a microgravity environment in a single horizontal axis. Digital Signal Processor (DSP) technology was used to calculate in real time, the control law between the accelerometer signals and the inertial actuators. The data obtained from this experiment verified that as much as 20 dB of rejection could be realized by this type of system. A discussion is included of recent tests performed in which vibrations were actively controlled in three axes simultaneously. In the three degree-of-freedom (3DOF) system, the air bearings were designed in such a way that the payload is free to rotate about the azimuth axis, as well as translate in the two horizontal directions. The actuator developed for the DAMPER project has applications beyond payload isolation, including structural damping and source vibration isolation. This report includes a brief discussion of these applications, as well as a commercialization plan for the actuator.

  17. Scintillator high-gain avalanche rushing photoconductor active-matrix flat panel imager: zero-spatial frequency x-ray imaging properties of the solid-state SHARP sensor structure.

    Science.gov (United States)

    Wronski, M; Zhao, W; Tanioka, K; Decrescenzo, G; Rowlands, J A

    2012-11-01

    The authors are investigating the feasibility of a new type of solid-state x-ray imaging sensor with programmable avalanche gain: scintillator high-gain avalanche rushing photoconductor active matrix flat panel imager (SHARP-AMFPI). The purpose of the present work is to investigate the inherent x-ray detection properties of SHARP and demonstrate its wide dynamic range through programmable gain. A distributed resistive layer (DRL) was developed to maintain stable avalanche gain operation in a solid-state HARP. The signal and noise properties of the HARP-DRL for optical photon detection were investigated as a function of avalanche gain both theoretically and experimentally, and the results were compared with HARP tube (with electron beam readout) used in previous investigations of zero spatial frequency performance of SHARP. For this new investigation, a solid-state SHARP x-ray image sensor was formed by direct optical coupling of the HARP-DRL with a structured cesium iodide (CsI) scintillator. The x-ray sensitivity of this sensor was measured as a function of avalanche gain and the results were compared with the sensitivity of HARP-DRL measured optically. The dynamic range of HARP-DRL with variable avalanche gain was investigated for the entire exposure range encountered in radiography∕fluoroscopy (R∕F) applications. The signal from HARP-DRL as a function of electric field showed stable avalanche gain, and the noise associated with the avalanche process agrees well with theory and previous measurements from a HARP tube. This result indicates that when coupled with CsI for x-ray detection, the additional noise associated with avalanche gain in HARP-DRL is negligible. The x-ray sensitivity measurements using the SHARP sensor produced identical avalanche gain dependence on electric field as the optical measurements with HARP-DRL. Adjusting the avalanche multiplication gain in HARP-DRL enabled a very wide dynamic range which encompassed all clinically relevant

  18. Scintillator high-gain avalanche rushing photoconductor active-matrix flat panel imager: Zero-spatial frequency x-ray imaging properties of the solid-state SHARP sensor structure

    International Nuclear Information System (INIS)

    Wronski, M.; Zhao, W.; Tanioka, K.; DeCrescenzo, G.; Rowlands, J. A.

    2012-01-01

    Purpose: The authors are investigating the feasibility of a new type of solid-state x-ray imaging sensor with programmable avalanche gain: scintillator high-gain avalanche rushing photoconductor active matrix flat panel imager (SHARP-AMFPI). The purpose of the present work is to investigate the inherent x-ray detection properties of SHARP and demonstrate its wide dynamic range through programmable gain. Methods: A distributed resistive layer (DRL) was developed to maintain stable avalanche gain operation in a solid-state HARP. The signal and noise properties of the HARP-DRL for optical photon detection were investigated as a function of avalanche gain both theoretically and experimentally, and the results were compared with HARP tube (with electron beam readout) used in previous investigations of zero spatial frequency performance of SHARP. For this new investigation, a solid-state SHARP x-ray image sensor was formed by direct optical coupling of the HARP-DRL with a structured cesium iodide (CsI) scintillator. The x-ray sensitivity of this sensor was measured as a function of avalanche gain and the results were compared with the sensitivity of HARP-DRL measured optically. The dynamic range of HARP-DRL with variable avalanche gain was investigated for the entire exposure range encountered in radiography/fluoroscopy (R/F) applications. Results: The signal from HARP-DRL as a function of electric field showed stable avalanche gain, and the noise associated with the avalanche process agrees well with theory and previous measurements from a HARP tube. This result indicates that when coupled with CsI for x-ray detection, the additional noise associated with avalanche gain in HARP-DRL is negligible. The x-ray sensitivity measurements using the SHARP sensor produced identical avalanche gain dependence on electric field as the optical measurements with HARP-DRL. Adjusting the avalanche multiplication gain in HARP-DRL enabled a very wide dynamic range which encompassed all

  19. High-Performance 1.55-µm Superluminescent Diode Based on Broad Gain InAs/InGaAlAs/InP Quantum Dash Active Region

    KAUST Repository

    Khan, Mohammed Zahed Mustafa; Ng, Tien Khee; Ooi, Boon S.

    2014-01-01

    of 140 nm, with a peak modal gain of ~41 cm-1. The noncoated two-section gainabsorber broad-area and ridge-waveguide device configuration exhibits an output power of > 20 mW and > 12 mW, respectively. The corresponding -3-dB bandwidths span ~82 nm and ~72

  20. Bioorganically doped sol-gel materials containing amyloglucosidase activity

    Directory of Open Access Journals (Sweden)

    Vlad-Oros Beatrice

    2006-01-01

    Full Text Available Amyloglucosidase (AMG from Aspergillus niger was encapsulated in various matrices derived from tetraethoxysilane, methyltriethoxysilane, phenyltriethoxysilane and vinyltriacetoxysilane by different methods of immobilization. The immobilized enzyme was prepared by entrapment in two steps, in one-step and entrapment/deposition, respectively. The activities of the immobilized AMG were assayed and compared with that of the native enzyme. The effects of the organosilaneprecursors and their molar ratios, the immobilization method, the inorganic support (white ceramic, red ceramic, purolite, alumina, TiO2, celite, zeolite and enzyme loading upon the immobilized enzyme activity were tested. The efficiency of the sol-gel biocomposites can be improved through combination of the fundamental immobilization techniques and selection of the precursors.

  1. Receiver gain function: the actual NMR receiver gain

    OpenAIRE

    Mo, Huaping; Harwood, John S.; Raftery, Daniel

    2010-01-01

    The observed NMR signal size depends on the receiver gain parameter. We propose a receiver gain function to characterize how much the raw FID is amplified by the receiver as a function of the receiver gain setting. Although the receiver is linear for a fixed gain setting, the actual gain of the receiver may differ from what the gain setting suggests. Nevertheless, for a given receiver, we demonstrate that the receiver gain function can be calibrated. Such a calibration enables accurate compar...

  2. Plasmonic modulator based on thin metal-semiconductor-metal waveguide with gain core

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Malureanu, Radu; Lavrinenko, Andrei

    2013-01-01

    We focus on plasmonic modulators with a gain core to be implemented as active nanodevices in photonic integrated circuits. In particular, we analyze metal–semiconductor–metal (MSM) waveguides with InGaAsP-based active material layers. A MSM waveguide enables high field localization and therefore...

  3. SANS-polymer and functional materials with neutron in Indonesia. Progress report on the collaboration activities?

    International Nuclear Information System (INIS)

    Ikram, A.; Gunawan; Sukirman, E.; Ridwan; Jahja, A.K.

    2000-01-01

    Activities on SANS-polymer collaboration program are reported. This paper presents SANS-data from Sodium Dodecyl Sulphate that have been obtained using BATAN's SANS machine in Serpong. Reports are also presented about activities in the groups for functional materials structural determination which includes magnetic, HTc superconducting and superionic conducting materials. Discussions are also given towards the way the collaboration activities were carried out in the last three years as well as impact of neutron scattering facility conditions in Indonesia. (author)

  4. Current studies of biological materials using instrumental and radiochemical neutron activation analysis

    International Nuclear Information System (INIS)

    Fardy, J.J.; McOrist, G.D.; Farrar, Y.J.

    1985-01-01

    Instrumental neutron activation analysis still remains the preferred option when analysing the trace element distribution in a wide rage of materials by neutron activation analysis. However, when lower limits of detection are required or major interferences reduce the effectiveness of this technique, radiochemical neutron activation analysis is applied. This paper examines the current use of both methods and the development of rapid radiochemical techniques for analysis of the biological materials, hair, cow's milk, human's milk, milk powder, blood and blood serum

  5. A tolerance analysis on design parameters of parabolic and hyperbolic secant active GRIN materials for laser beam shaping purposes

    International Nuclear Information System (INIS)

    Gómez-Varela, A I; Bao-Varela, C; Flores-Arias, M T

    2014-01-01

    The present paper considers two gain GRIN media, characterized by a complex parabolic and hyperbolic secant refractive index profile, for the design of uniform beam shaper systems. A general condition for beam shaping is obtained from the equation describing the evolution of the half-width of a plane Gaussian beam in the GRIN media. The simulation of the irradiance evolution of an input plane Gaussian beam—operating at 575 nm and beam waist radius of 0.45 mm—in each material is shown, in order to examine the beam shaping quality in terms of thickness of the active GRIN media and input beam wavelength. (paper)

  6. Active and Intelligent Materials for Food Packaging Applications

    OpenAIRE

    Buškuvienė, Nijolė; Jankauskaitė, Virginija

    2017-01-01

    World Health Organization (WHO) reveals the growing problem of food-borne illness around the world. Hundreds of millions of people worldwide are getting sick from contaminated food, because 1/3 - 1/2 of food products are not consumed (EC Directives 80/590/EEC and 89/109/EEC). Therefore, the preservation of food freshness and shelf life extension is important task for researchers around the world. In the last decade, much attention is paid to active and intelligent packaging investigation, dev...

  7. Method for monitoring drilling materials for gamma ray activity

    International Nuclear Information System (INIS)

    Smith, H.D. Jr.; Arnold, D.M.; Schultz, W.E.

    1985-01-01

    This invention relates to a method of verifying the radioactivity levels in raw barite prior to its use in drilling mud. Certain gamma ray measurements are taken of the raw barite and extrapolated to a well bore environment using the projected drilling mud weight made from this barite and the dimensions of the well bore. The natural radioactivity occurring in the formations in the vicinity of the well bore is then compared with the projected levels to enable a determination of whether or not the barite has sufficient radioactive trace elements to forbid its use in a well. Alternatively, the method indicates the ratios by which such additives containing radioactive trace elements must be diluted with non-radioactive additives before use in the drilling mud. A second use of the method involves mud testing at the well site for radioactivity from mud additives, including barite, potassium chloride, and well cuttings. Additional uses include testing other weight materials prior to or subsequent to addition to the mud, and methods for correcting observed gamma ray measurements for the mud-induced background

  8. Receiver Gain Modulation Circuit

    Science.gov (United States)

    Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen

    2011-01-01

    A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by

  9. Photocatalytic degradation of sunscreen active ingredients mediated by nanostructured materials

    Science.gov (United States)

    Soto-Vazquez, Loraine

    Water scarcity and pollution are environmental issues with terrible consequences. In recent years several pharmaceutical and personal care products, such as sunscreen active ingredients, have been detected in different water matrices. Its recalcitrant behavior in the environment has caused controversies and generated countless questions about its safety. During this research, we employed an advanced oxidation process (photocatalysis) to degrade sunscreen active ingredients. For this study, we used a 3x3 system, evaluating three photocatalysts and three different contaminants. From the three catalysts employed, two of them were synthesized. ZnO nanoparticles were obtained using zinc acetate dihydrated as the precursor, and TiO2 nanowires were synthesized from titanium tetrachloride precursor. The third catalyst employed (namely, P25) was obtained commercially. The synthesized photocatalysts were characterized in terms of the morphology, elemental composition, crystalline structure, elemental oxidation states, vibrational modes and surface area, using SEM-EDS, XRD, XPS, Raman spectroscopy and BET measurements, respectively. The photocatalysts were employed during the study of the degradation of p-aminobenzoic acid, phenylbenzimidazole sulfonic acid, and benzophenone-4. In all the cases, at least 50% degradation was achieved. P25 showed degradation efficiencies above 90%, and from the nine systems, 7 of them degraded at least 86%.

  10. Activity measurement and effective dose modelling of natural radionuclides in building material.

    Science.gov (United States)

    Maringer, F J; Baumgartner, A; Rechberger, F; Seidel, C; Stietka, M

    2013-11-01

    In this paper the assessment of natural radionuclides' activity concentration in building materials, calibration requirements and related indoor exposure dose models is presented. Particular attention is turned to specific improvements in low-level gamma-ray spectrometry to determine the activity concentration of necessary natural radionuclides in building materials with adequate measurement uncertainties. Different approaches for the modelling of the effective dose indoor due to external radiation resulted from natural radionuclides in building material and results of actual building material assessments are shown. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Materialism.

    Science.gov (United States)

    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. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Influence of various Activated Carbon based Electrode Materials in the Performance of Super Capacitor

    Science.gov (United States)

    Ajay, K. M.; Dinesh, M. N.

    2018-02-01

    Various activated carbon based electrode materials with different surface areas was prepared on stainless steel based refillable super capacitor model using spin coating. Bio Synthesized Activated Carbon (BSAC), Activated Carbon (AC) and Graphite powder are chosen as electrode materials in this paper. Electrode materials prepared using binder solution which is 6% by wt. polyvinylidene difluoride, 94% by wt. dimethyl fluoride. 3M concentrated KOH solution is used as aqueous electrolyte with PVDF thin film as separator. It is tested for electrochemical characterizations and material characterizations. It is observed that the Specific capacitance of Graphite, Biosynthesized active carbon and Commercially available activated carbon are 16.1F g-1, 53.4F g-1 and 107.6F g-1 respectively at 5mV s-1 scan rate.

  13. Do you want the good news or the bad news? Gain- versus loss-framed messages following health risk information: The effects on leisure time physical activity beliefs and cognitions.

    Science.gov (United States)

    Bassett-Gunter, Rebecca L; Martin Ginis, Kathleen A; Latimer-Cheung, Amy E

    2013-12-01

    The primary purpose was to examine the relative effectiveness of chronic disease and psychological health risk information combined with gain- versus loss-framed leisure time physical activity (LTPA) messages for changing perceived personal risk, LTPA response efficacy (i.e., the belief that LTPA can effectively reduce risk), and LTPA intentions. A secondary purpose was to explore the relationship between message framing and cognitive processing. Baseline assessments of perceived risk for inactivity-related disease and psychological health problems, LTPA response efficacy, and intentions were measured among 96 individuals with spinal cord injury (SCI). Participants read population-specific information about the risk for inactivity-related disease and psychological health problems following SCI, and perceived risk was reassessed. Participants were then randomized to read LTPA response efficacy messages emphasizing the benefits of LTPA (gain framed) or the risks of inactivity (loss framed). Immediately following message exposure, cognitive processing (i.e., thought listing and message recall), LTPA response efficacy, and LTPA intentions were assessed. Changes in perceived risk were observed following exposure to health risk information. Changes in LTPA response efficacy and intentions were greater following loss-framed messages targeting psychological health compared with gain-framed messages. Greater cognitive processing was observed following loss-framed messages compared with gain-framed messages. Following exposure to psychological health risk information, loss-framed messages may be more effective than gain-framed messages for eliciting cognitive processing and changing LTPA beliefs and intentions.

  14. Photomultiplier gain stabilisation

    International Nuclear Information System (INIS)

    Le Baud, P.; Sautiez, B.

    1958-07-01

    By the control and adjustment of magnetic deflection applied to the electron beam of a photomultiplier it has proved possible to flatten the gain curve, forming plateaux at levels dependent upon the voltage at intake. It should be possible to add this simple device to most photomultipliers on the market today. (author) [fr

  15. Early metabolic adaptation in C57BL/6 mice resistant to high fat diet induced weight gain involves an activation of mitochondrial oxidative pathways.

    Science.gov (United States)

    Boulangé, Claire L; Claus, Sandrine P; Chou, Chieh J; Collino, Sebastiano; Montoliu, Ivan; Kochhar, Sunil; Holmes, Elaine; Rezzi, Serge; Nicholson, Jeremy K; Dumas, Marc E; Martin, François-Pierre J

    2013-04-05

    We investigated the short-term (7 days) and long-term (60 days) metabolic effect of high fat diet induced obesity (DIO) and weight gain in isogenic C57BL/6 mice and examined the specific metabolic differentiation between mice that were either strong-responders (SR), or non-responders (NR) to weight gain. Mice (n = 80) were fed a standard chow diet for 7 days prior to randomization into a high-fat (HF) (n = 56) or a low-fat (LF) (n = 24) diet group. The (1)H NMR urinary metabolic profiles of LF and HF mice were recorded 7 and 60 days after the diet switch. On the basis of the body weight gain (BWG) distribution of HF group, we identified NR mice (n = 10) and SR mice (n = 14) to DIO. Compared with LF, HF feeding increased urinary excretion of glycine conjugates of β-oxidation intermediate (hexanoylglycine), branched chain amino acid (BCAA) catabolism intermediates (isovalerylglycine, α-keto-β-methylvalerate and α-ketoisovalerate) and end-products of nicotinamide adenine dinucleotide (NAD) metabolism (N1-methyl-2-pyridone-5-carboxamide, N1-methyl-4-pyridone-3-carboxamide) suggesting up-regulation of mitochondrial oxidative pathways. In the HF group, NR mice excreted relatively more hexanoylglycine, isovalerylglycine, and fewer tricarboxylic acid (TCA) cycle intermediate (succinate) in comparison to SR mice. Thus, subtle regulation of ketogenic pathways in DIO may alleviate the saturation of the TCA cycle and mitochondrial oxidative metabolism.

  16. 'Low-activation' fusion materials development and related nuclear data needs

    International Nuclear Information System (INIS)

    Cierjacks, S.

    1990-01-01

    So-called ''low-activation'' materials are presently considered as an important means of improving the safety characteristics of future DT fusion reactors. Essential benefits are expected in various problem areas ranging from operation considerations to aspects of decommissioning and waste disposal. Present programs on ''low-activation'' materials development depend strongly on reliable activity calculations for a wide range of technologically important materials. The related nuclear data requirements and important needs for more and improved nuclear data are discussed. (author). 32 refs, 4 figs, 4 tabs

  17. Electron transport system activity of microfouling material: Relationships with biomass parameters

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Tulaskar, A.; Wagh, A.B.

    (ETS). The ETS activity ranged from 720 to 1374 ~kg 0@d2@@ dm@u2@@ d@u-1@@. Microfouling biomass and ETS activity of microfouling material increased with the immersion period. ETS activity was significantly correlated with dry weight, organic carbon...

  18. Calculation of Airborne Radioactivity Hazard from Machining Volume-Activated Materials

    International Nuclear Information System (INIS)

    E.T. Marshall; S.O. Schwahn

    1997-01-01

    When evaluating a task involving the machining of volume-activated materials, accelerator health physicists must consider more than the surface contamination levels of the equipment and containment of loose shavings, dust or filings. Machining operations such as sawing, routing, welding, and grinding conducted on volume-activated material may pose a significant airborne radioactivity hazard to the worker. This paper presents a computer spreadsheet notebook that conservatively estimates the airborne radioactivity levels generated during machining operations performed on volume-activated materials. By knowing (1) the size and type of materials, (2) the dose rate at a given distances, and (3) limited process knowledge, the Derived Air Concentration (DAC) fraction can be estimated. This tool is flexible, taking into consideration that the process knowledge available for the different materials varies. It addresses the two most common geometries: thick plane and circular cylinder. Once the DAC fraction has been estimated, controls can be implemented to mitigate the hazard to the worker

  19. Calculation of airborne radioactivity hazard from machining volume-activated materials

    International Nuclear Information System (INIS)

    Marshall, E.T.; Schwahn, S.O.

    1996-10-01

    When evaluating a task involving the machining of volume-activated materials, accelerator health physicists must consider more than the surface contamination levels of the equipment and containment of loose shavings, dust or filings. Machining operations such as sawing, routing, welding, and grinding conducted on volume-activated material may pose a significant airborne radioactivity hazard to the worker. This paper presents a computer spreadsheet notebook that conservatively estimates the airborne radioactivity levels generated during machining operations performed on volume-activated materials. By knowing (1) the size and type of materials, (2) the dose rate at a given distances, and (3) limited process knowledge, the Derived Air Concentration (DAC) fraction can be estimated. This tool is flexible, taking into consideration that the process knowledge available for the different materials varies. It addresses the two most common geometries: thick plane and circular cylinder. Once the DAC fraction has been estimated, controls can be implemented to mitigate the hazard to the worker

  20. On the possibility of multiple utilization of Bowen's Kale for neutron activation analysis of biological materials

    International Nuclear Information System (INIS)

    Marinov, V.M.; Lazarova, M.S.; Mihajlov, M.I.; Apostolov, D.

    1977-01-01

    The results of investigations related to the multiple utilization of Bowen's Kale in developing neutron-activation methods for determining microelements in biological materials carried out in recent years are presented. Bowen's Kale might be used as: (1) experimental material in the development of a method and its verification, i.e. as a test for biological materials; (2) a material where experimental conditions might be optimized; (3) a material for investigating the accuracy, reproducibility and the limit of proof at experimental conditions already defined; (4) a monitor; (5) a multielement volume reference standard for a number of microelements during their simultaneous determination and (6) a standard for verifying the authenticity of the results obtained. In this manner, a reliable criterion for comparison of the potentialities, the accuracy, reproducibility, the limits of proof and the authenticity of the neutron-activation methods of determining microelements in biological materials is introduced. (author)

  1. To the question of peculiarities of thermal activation of natural siliceous raw material

    Directory of Open Access Journals (Sweden)

    Chumachenko Natalya

    2017-01-01

    Full Text Available The results of research of activity enhancement of natural siliceous raw material are given in the article. Fossil meal of Khotynetsky deposit, diatomite of Sharlovsky deposit, silica clay of Balasheika deposit were used as natural active mineral admixtures. The influence of heat-treating temperature and dispersion on activity of different types of siliceous raw material is studied. The increase of activity of fixation of Ca(OH2 in several times is traced after heat-treating at a certain temperature in the range from 100 to 800°C. The type of activity change is discovered. Explanation is given connected with the change of silica structure in the surface layer. Parameters of the highest activity are defined for every type of siliceous raw material.

  2. Mechanical properties of alkali-activated materials based on blast furnace slag and calcium sulphate dihdyrate

    OpenAIRE

    Gijbels, Katrijn; Pontikes, Yiannis; Ion Iacobescu, Remus; Schreurs, Sonja; Schroeyers, Wouter

    2017-01-01

    Alkali-activated materials (AAMs) are currently under research for providing opportunities for re-use of industrial residue streams in the construction sector. The valorisation of industrial residues into sustainable building materials has become an important feature for reducing the need of disposal and avoid the scarcity of primary resources. The use of ordinary Portland cement (OPC) as primary construction material has also been questioned extensively due to its environmental impact, i.e. ...

  3. Transient optical gain in germanium quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Chatterjee, Sangam; Lange, Christoph; Koester, Niko S.; Schaefer, Martin; Kira, Mackillo; Koch, Stephan W. [Faculty of Physics and Materials Sciences Center, Philipps-Universitaet Marburg (Germany); Chrastina, Daniel; Isella, Giovanni; Kaenel, Hans von [CNISM, Como (Italy); L-NESS, Dipartimento di Fisica del Politecnico di Milano, Como (Italy); Sigg, Hans [Laboratory for Micro and Nanotecnology, Paul Scherrer Institut, Villigen PSI (Switzerland)

    2010-07-01

    One of today's most-sought goals in semiconductor technology is the monolithic integration of microelectronics and photonics on Si. Optical gain is, in general, not expected for Si and Ge or its alloys due to the indirect nature of the band gap in this material system. Here, we show that Ge/SiGe QWs show transient optical gain and may thus be used as an optically-pumped amplifier at room temperature. Further, the nonequilibrium effects which govern the relaxation dynamics of the optically injected carrier distributions in this material were observed and analyzed using a microscopic many-body theory. Strong non-equilibrium gain was obtained on a sub-100 fs time scale. Long-lived gain arising from {gamma}-point transitions is overcompensated by a process bearing the character of free carrier absorption.

  4. Next Generation , Lightweight, Durable Boot Materials to Provide Active & Passive Thermal Protection, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this NASA Phase I SBIR program is to leverage lightweight, durable materials developed by NanoSonic for use within extra vehicular activity (EVA)...

  5. Activated graphene as a cathode material for Li-ion hybrid supercapacitors.

    Science.gov (United States)

    Stoller, Meryl D; Murali, Shanthi; Quarles, Neil; Zhu, Yanwu; Potts, Jeffrey R; Zhu, Xianjun; Ha, Hyung-Wook; Ruoff, Rodney S

    2012-03-14

    Chemically activated graphene ('activated microwave expanded graphite oxide', a-MEGO) was used as a cathode material for Li-ion hybrid supercapacitors. The performance of a-MEGO was first verified with Li-ion electrolyte in a symmetrical supercapacitor cell. Hybrid supercapacitors were then constructed with a-MEGO as the cathode and with either graphite or Li(4)Ti(5)O(12) (LTO) for the anode materials. The results show that the activated graphene material works well in a symmetrical cell with the Li-ion electrolyte with specific capacitances as high as 182 F g(-1). In a full a-MEGO/graphite hybrid cell, specific capacitances as high as 266 F g(-1) for the active materials at operating potentials of 4 V yielded gravimetric energy densities for a packaged cell of 53.2 W h kg(-1).

  6. Catalytic activity of bed materials from industrial CFB boilers for the decomposition of N2O

    International Nuclear Information System (INIS)

    Barisic, V.; Klingstedt, F.; Kilpinen, P.; Hupa, M.; Naydenov, A.; Stefanov, P.

    2005-01-01

    The correlation between the catalytic activity towards N 2 O decomposition and fuel type was studied for the bed materials sampled from the bottom bed of two industrial CFB boilers, a 12MW th and a 550MW th , burning biomass fuels and wastes, alone or as a mixture. It was found that the elemental composition of the surface of the bed material particles changed according to the composition of the ash from the parent fuel. The measured catalytic activity of the bed material samples increased with the amount of the catalytically active oxides (CaO, MgO, Fe 2 O 3 , Al 2 O 3 ). In the case of limestone addition, the activity of the bed material was influenced by both the elemental composition of the fuel, and the ratio between lime and sulfated lime

  7. 77 FR 38395 - Agency Information Collection Activities (Advertising, Sales, and Enrollment Materials, and...

    Science.gov (United States)

    2012-06-27

    ... Activities (Advertising, Sales, and Enrollment Materials, and Candidate Handbooks) Under OMB Review AGENCY... correspondence. FOR FURTHER INFORMATION OR A COPY OF THE SUBMISSION CONTACT: Denise McLamb, Enterprise Records....'' SUPPLEMENTARY INFORMATION: Title: Advertising, Sales, and Enrollment Materials, and Candidate Handbooks, 38 CFR...

  8. Research activities on structure materials of spallation neutron source at SINQ

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, G.S.; Dai, Y. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    With the growing interests on powerful spallation neutron sources, especially with liquid metal targets, and accelerator driven energy systems, spallation materials science and technology have been received wide attention. At SINQ, material research activities are focused on: a) liquid metal corrosion; b) radiation damage; and c) interaction of corrosion and radiation damage. (author) 1 fig., refs.

  9. Determination of trace elements in biological material by neutron activation analysis

    International Nuclear Information System (INIS)

    Tran Van, L.; Teherani, D.K.

    1989-01-01

    Eighteen trace elements in biological materials [grass (Imperata cylindrica), mimosa plant (Mimosa pudica), rice] by neutron activation method were determined. In the comparative analysis the content of the same element was different in each material, although they were collected at the same place and the same sampling method was applied. (author) 4 refs.; 1 fig.; 1 tab

  10. Quality and Knowledge Content in Music Activities in Preschool: The Impact of Human Materiality Combinations

    Science.gov (United States)

    Zimmerman Nilsson, Marie-Helene; Holmberg, Kristina

    2017-01-01

    Traditionally, pedagogical research has been child centered, where materialities often have been considered as objects and tools. However, in recent posthuman research, attempts have been made to consider human materiality combinations to have impact on pedagogical activities in preschool, but to a large extent music as an issue has been…

  11. Active video games as a tool to prevent excessive weight gain in adolescents: rationale, design and methods of a randomized controlled trial

    NARCIS (Netherlands)

    Simons, M.; Chinapaw, M.J.M.; Bovenkamp, van de M.; Boer, de M.R.; Seidell, J.C.; Brug, J.; Vet, de E.

    2014-01-01

    Background Excessive body weight, low physical activity and excessive sedentary time in youth are major public health concerns. A new generation of video games, the ones that require physical activity to play the games –i.e. active games- may be a promising alternative to traditional non-active

  12. Active video games as a tool to prevent excessive weight gain in adolescents : rationale, design and methods of a randomized controlled trial

    NARCIS (Netherlands)

    Simons, Monique; Chinapaw, Mai J M; van de Bovenkamp, Maaike; de Boer, Michiel R; Seidell, Jacob C; Brug, Johannes; de Vet, Emely

    2014-01-01

    BACKGROUND: Excessive body weight, low physical activity and excessive sedentary time in youth are major public health concerns. A new generation of video games, the ones that require physical activity to play the games--i.e. active games--may be a promising alternative to traditional non-active

  13. Active video games as a tool to prevent excessive weight gain in adolescents: Rationale, design and methods of a randomized controlled trial

    NARCIS (Netherlands)

    Simons, M.; Chinapaw, M.J.; Bovenkamp, M. van de; Boer, M.R. de; Seidell, J.C.; Brug, J.; Vet, E. de

    2014-01-01

    Background: Excessive body weight, low physical activity and excessive sedentary time in youth are major public health concerns. A new generation of video games, the ones that require physical activity to play the games -i.e. active games- may be a promising alternative to traditional non-active

  14. Materials selection as an interdisciplinary technical activity: basic methodology and case studies

    Directory of Open Access Journals (Sweden)

    M. Ferrante

    2000-04-01

    Full Text Available The technical activity known as Materials Selection is reviewed in its concepts and methodologies. Objectives and strategies are briefly presented and two important features are introduced and discussed; (i Merit Indices: a combination of materials properties, which maximises the objectives chosen by the designer and (ii Materials Properties Maps: a bi-dimensional space whose coordinates are pairs of properties in which materials can be plotted and compared directly in terms of their merit indices. A general strategy for the deduction of these indices is explained and a formal methodology to establish a ranking of candidate materials when multiple constraints intervene is presented. Finally, two case studies are discussed in depth, one related to materials substitution in the context of mechanical design and a less conventional case linking material selection to physical comfort in the home furniture industry.

  15. Learn and gain

    CERN Document Server

    Al-Alami, Suhair Eyad Jamal

    2013-01-01

    Initiating the slogan ""love it, live it"", Learn and Gain includes eight short stories, chosen to illustrate various modes of narration, as well as to provoke reflection and discussion on a range of issues. All texts utilized here illustrate how great writers can, with their insight and gift for words, help us to see the world we live in, in new probing and exciting ways. What characterises the book, the author believes, is the integration of the skills of literary competence, communicative c...

  16. Rattling nucleons: New developments in active interrogation of special nuclear material

    International Nuclear Information System (INIS)

    Runkle, Robert C.; Chichester, David L.; Thompson, Scott J.

    2012-01-01

    Active interrogation is a vigorous area of research and development due to its promise of offering detection and characterization capabilities of special nuclear material in environments where passive detection fails. The primary value added by active methods is the capability to penetrate shielding - special nuclear material itself, incidental materials, or intentional shielding - and advocates hope that active interrogation will provide a solution to the problem of detecting shielded uranium, which is at present the greatest obstacle to interdiction efforts. The technique also provides a unique benefit for quantifying nuclear material in high background-radiation environments, an area important for nuclear material safeguards and material accountancy. Progress has been made in the field of active interrogation on several fronts, most notably in the arenas of source development, systems integration, and the integration and exploitation of multiple fission and non-fission signatures. But penetration of interrogating radiation often comes at a cost, not only in terms of finance and dose but also in terms of induced backgrounds, system complexity, and extended measurement times (including set up and acquisition). These costs make the calculus for deciding to implement active interrogation more subtle than may be apparent. The purpose of this review is thus to examine existing interrogation methods, compare and contrast their attributes and limitations, and identify missions where active interrogation may hold the most promise.

  17. Risk assessment of manual material handling activities (case study: PT BRS Standard Industry)

    Science.gov (United States)

    Deviani; Triyanti, V.

    2017-12-01

    The process of moving material manually has the potential for injury to workers. The risk of injury will increase if we do not pay attention to the working conditions. The purpose of this study is to assess and analyze the injury risk level in manual handling material activity, as well as to improve the condition. The observed manual material handling activities is pole lifting and goods loading. These activities were analyzed using Job Strain Index method, Rapid Entire Body Assessment, and Chaffin’s 2D Planar Static Model. The results show that most workers who perform almost all activities have a high level of risk level with the score of JSI and REBA exceeds 9 points. For some activities, the estimated compression forces in the lumbar area also exceed the standard limits of 3400 N. Concerning this condition, several suggestions for improvement were made, improving the composition of packing, improving body posture, and making guideline posters.

  18. Materials

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2009-02-01

    Full Text Available . It is generally included as part of a structurally insulated panel (SIP) where the foam is sandwiched between external skins of steel, wood or cement. Cement composites Cement bonded composites are an important class of building materials. These products... for their stone buildings, including the Egyptians, Aztecs and Inca’s. As stone is a very dense material it requires intensive heating to become warm. Rocks were generally stacked dry but mud, and later cement, can be used as a mortar to hold the rocks...

  19. IFMIF : International Fusion Materials Irradiation Facility Conceptual Design Activity: Executive summary

    International Nuclear Information System (INIS)

    1997-01-01

    This report is a summary of the results of the Conceptual Design Activity (CDA) on the International Fusion Materials Irradiation Facility (IFMIF), conducted during 1995 and 1996. The activity is under the auspices of the International Energy Agency (IEA) Implementing Agreement for a Programme of Research and Development on Fusion Materials. An IEA Fusion Materials Executive Subcommittee was charged with overseeing the IFMIF-CDA work. Participants in the CDA are the European Union, Japan, and the United States, with the Russian Federation as an associate member

  20. IFMIF : International Fusion Materials Irradiation Facility Conceptual Design Activity: Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    This report is a summary of the results of the Conceptual Design Activity (CDA) on the International Fusion Materials Irradiation Facility (IFMIF), conducted during 1995 and 1996. The activity is under the auspices of the International Energy Agency (IEA) Implementing Agreement for a Programme of Research and Development on Fusion Materials. An IEA Fusion Materials Executive Subcommittee was charged with overseeing the IFMIF-CDA work. Participants in the CDA are the European Union, Japan, and the United States, with the Russian Federation as an associate member.

  1. IFMIF : International Fusion Materials Irradiation Facility Conceptual Design Activity: Final report

    International Nuclear Information System (INIS)

    Martone, M.

    1997-01-01

    This report documents the results of the Conceptual Design Activity (CDA) on the International Fusion Materials Irradiation Facility (IFMIF), conducted during 1995 and 1996. The activity is under the auspices of the International Energy Agency (IEA) Implementing Agreement for a Programme of Research and Development on Fusion Materials. An IEA Fusion Materials Executive Subcommittee was charged with overseeing the IFMIF-CDA work. Participants in the CDA are the European Union, Japan, and the United States, with the Russian Federation as an associate member

  2. IFMIF : International Fusion Materials Irradiation Facility Conceptual Design Activity: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Martone, M [ENEA, Centro Ricerche Frascati, Rome (Italy)

    1997-01-01

    This report documents the results of the Conceptual Design Activity (CDA) on the International Fusion Materials Irradiation Facility (IFMIF), conducted during 1995 and 1996. The activity is under the auspices of the International Energy Agency (IEA) Implementing Agreement for a Programme of Research and Development on Fusion Materials. An IEA Fusion Materials Executive Subcommittee was charged with overseeing the IFMIF-CDA work. Participants in the CDA are the European Union, Japan, and the United States, with the Russian Federation as an associate member.

  3. Percolated microstructures for multi-modal transport enhancement in porous active materials

    Energy Technology Data Exchange (ETDEWEB)

    McKay, Ian Salmon; Yang, Sungwoo; Wang, Evelyn N.; Kim, Hyunho

    2018-03-13

    A method of forming a composite material for use in multi-modal transport includes providing three-dimensional graphene having hollow channels, enabling a polymer to wick into the hollow channels of the three-dimensional graphene, curing the polymer to form a cured three-dimensional graphene, adding an active material to the cured three-dimensional graphene to form a composite material, and removing the polymer from within the hollow channels. A composite material formed according to the method is also provided.

  4. Total gamma activity measurements for determining the radioactivity of residual materials from nuclear power stations

    International Nuclear Information System (INIS)

    Auler, I.; Meyer, M.; Stickelmann, J.

    1995-01-01

    Large amounts of residual materials from retrofitting measures and from decommissioning of nuclear power stations shows such a weak level of radioactivity that they could be released after decision measurements. Expenses incurred with complex geometry cannot be taken with common methods. NIS developed a Release Measurement Facility (RMF) based on total gamma activity measurements especially for these kind of residual materials. The RMF has been applied for decision measurements in different nuclear power plants. Altogether about 2,000 Mg of various types of materials have been measured up to now. More than 90 % of these materials could be released 0 without any restriction after decision measurements

  5. Determination of contaminants in rare earth materials by prompt gamma activation analysis (PGAA)

    International Nuclear Information System (INIS)

    Perry, D.L.; English, G.A.; Firestone, R.B.; Molnar, G.L.; Revay, Zs.

    2005-01-01

    Prompt gamma activation analysis (PGAA) has been used to detect and quantify impurities in the analyses of rare earth (RE) oxides. The analytical results are discussed with respect to the importance of having a thorough identification and contaminant elements in these compounds regarding the function of the materials in their various applications. Also, the importance of using PGAA to analyze materials in support of other physico-chemical studies of the materials is discussed, including the study of extremely low concentrations of ions - such as the rare earth ions themselves - in bulk material matrices. (author)

  6. Light-induced antibacterial activity of electrospun chitosan-based material containing photosensitizer

    Energy Technology Data Exchange (ETDEWEB)

    Severyukhina, A.N., E-mail: severyuhina_alexandra@mail.ru [Institute of Nanostructures and Biosystems, Saratov State University, 410012 Saratov (Russian Federation); Petrova, N.V.; Yashchenok, A.M. [Institute of Nanostructures and Biosystems, Saratov State University, 410012 Saratov (Russian Federation); Bratashov, D.N. [Institute of Nanostructures and Biosystems, Saratov State University, 410012 Saratov (Russian Federation); Department of Nano- and Biomedical Technologies, Saratov State University, 410012 Saratov (Russian Federation); Smuda, K. [Institute of Transfusion Medicine, Charité-Universitätsmedizin, 10117 Berlin (Germany); Mamonova, I.A. [Institute of Traumatology and Orthopedics, 410002 Saratov (Russian Federation); Yurasov, N.A. [Institute of Nanostructures and Biosystems, Saratov State University, 410012 Saratov (Russian Federation); Puchinyan, D.M. [Institute of Nanostructures and Biosystems, Saratov State University, 410012 Saratov (Russian Federation); Institute of Traumatology and Orthopedics, 410002 Saratov (Russian Federation); Georgieva, R. [Institute of Transfusion Medicine, Charité-Universitätsmedizin, 10117 Berlin (Germany); Department of Medical Physics, Biophysics and Radiology, Medical Faculty, Trakia University, 6000 Stara Zagora (Bulgaria); Bäumler, H. [Institute of Transfusion Medicine, Charité-Universitätsmedizin, 10117 Berlin (Germany); Lapanje, A. [Institute of Nanostructures and Biosystems, Saratov State University, 410012 Saratov (Russian Federation); Josef Stefan Institute, 1000 Ljubljana (Slovenia); Gorin, D.A. [Institute of Nanostructures and Biosystems, Saratov State University, 410012 Saratov (Russian Federation); Department of Nano- and Biomedical Technologies, Saratov State University, 410012 Saratov (Russian Federation)

    2017-01-01

    Increasing antimicrobial resistance requires the development of novel materials and approaches for treatment of various infections. Utilization of photodynamic therapy represents an advanced alternative to antibiotics and metal-based agents. Here, we report the fabrication of electrospun material that possesses benefits of both topical antimicrobial and photodynamic therapies. This material combines chitosan, as a biocompatible polymer, and a second generation photosensitizer. The incorporation of photosensitizer doesn't affect the material morphology and its nearly uniform distribution in fibers structure was observed by confocal Raman microscopy. Owing to photosensitizer the prepared material exhibits the light-induced and spatially limited antimicrobial activity that was demonstrated against Staphylococcus aureus, an important etiological infectious agent. Such material can be potentially used in antibacterial therapy of chronic wounds, infections of diabetic ulcers, and burns, as well as rapidly spreading and intractable soft-tissue infections caused by resistant bacteria. - Highlights: • Chitosan with a phthalocyanine photosensitizer was electrospun into fibers. • Photosensitizer was uniformly distributed in the electrospun material. • The incorporation of photosensitizer does not affect the fiber morphology. • Chitosan/photosensitizer composites possess light-induced antibacterial activity. • The antibacterial activity of the material is limited to the area of irradiation.

  7. Energy Gaining Windows for Residental Buildings

    DEFF Research Database (Denmark)

    Kragh, Jesper; Laustsen, Jacob Birck; Svendsen, Svend

    2008-01-01

    window is made of fiber-reinforced plastic (plastic reinforced by fine fibers made of glass). This composite material is a weatherproof material with very low thermal conductivity and high mechanical strength. These properties make the material very suitable for frame profiles due to lower heat loss...... minus the heat loss integrated over the heating season. It is assumed that in northern cold climates all of the solar gain during the heating season can be utilized for space heating. Problems with overheating in the summer period must be solved with overhang or moveable solar shading devices. Two...... and longer durability of the window. The glazing in these fiber reinforced polyester windows is both unsealed and sealed triple glazing units. To increase the net energy gain slim frame profiles have been developed to increase the glazing area and thereby the solar gain. The challenge when developing slim...

  8. Efficiency of biological activator formulated material (BAFM) for volatile organic compounds removal--preliminary batch culture tests with activated sludge.

    Science.gov (United States)

    Corre, Charline; Couriol, Catherine; Amrane, Abdeltif; Dumont, Eric; Andrès, Yves; Le Cloirec, Pierre

    2012-01-01

    During biological degradation, such as biofiltration of air loaded with volatile organic compounds, the pollutant is passed through a bed packed with a solid medium acting as a biofilm support. To improve microorganism nutritional equilibrium and hence to enhance the purification capacities, a Biological Activator Formulated Material (BAFM) was developed, which is a mixture of solid nutrients dissolving slowly in a liquid phase. This solid was previously validated on mineral pollutants: ammonia and hydrogen sulphide. To evaluate the efficiency of such a material for biodegradation of some organic compounds, a simple experiment using an activated sludge batch reactor was carried out. The pollutants (sodium benzoate, phenol, p-nitrophenol and 2-4-dichlorophenol) were in the concentration range 100 to 1200 mg L(-1). The positive impact of the formulated material was shown. The improvement of the degradation rates was in the range 10-30%. This was the consequence of the low dissolution of the nutrients incorporated during material formulation, followed by their consumption by the biomass, as shown for urea used as a nitrogen source. Owing to its twofold interest (mechanical resistance and nutritional supplementation), the Biological Activator Formulated Material seems to be a promising material. Its addition to organic or inorganic supports should be investigated to confirm its relevance for implementation in biofilters.

  9. IFMIF - International Fusion Materials Irradiation Facility Conceptual Design Activity/Interim Report

    International Nuclear Information System (INIS)

    Rennich, M.J.

    1995-12-01

    Environmental acceptability, safety, and economic viability win ultimately be the keys to the widespread introduction of fusion power. This will entail the development of radiation- resistant and low- activation materials. These low-activation materials must also survive exposure to damage from neutrons having an energy spectrum peaked near 14 MeV with annual radiation doses in the range of 20 displacements per atom (dpa). Testing of candidate materials, therefore, requires a high-flux source of high energy neutrons. The problem is that there is currently no high-flux source of neutrons in the energy range above a few MeV. The goal, is therefore, to provide an irradiation facility for use by fusion material scientists in the search for low-activation and damage-resistant materials. An accellerator-based neutron source has been established through a number of international studies and workshops' as an essential step for materials development and testing. The mission of the International Fusion Materials Irradiation Facility (IFMIF) is to provide an accelerator-based, deuterium-lithium (D-Li) neutron source to produce high energy neutrons at sufficient intensity and irradiation volume to test samples of candidate materials up to about a full lifetime of anticipated use in fusion energy reactors. would also provide calibration and validation of data from fission reactor and other accelerator-based irradiation tests. It would generate material- specific activation and radiological properties data, and support the analysis of materials for use in safety, maintenance, recycling, decommissioning, and waste disposal systems

  10. Gains from quota trade

    DEFF Research Database (Denmark)

    Andersen, Jesper Levring; Bogetoft, Peter

    2007-01-01

    We provide a framework for evaluating potential effects of introducing tradable quotas to a sector. The effects depend on the economies of scale and scope of the production technology, and on firms' ability and willingness to learn best practice methods (catching up) and to change their input...... and output composition (mix). To illustrate our approach, data from the Danish fishery are used to calculate the potential gains from introducing individually transferable fishing quotas. Data envelopment analysis is used to model the production technology. We find that pure reallocation is as important...

  11. Gaining Relational Competitive Advantages

    DEFF Research Database (Denmark)

    Hu, Yimei; Zhang, Si; Li, Jizhen

    2015-01-01

    Establishing strategic technological partnerships (STPs) with foreign partners is an increasingly studied topic within the innovation management literature. Partnering firms can jointly create sources of relational competitive advantage. Chinese firms often lack research and development (R......&D) capabilities but are increasingly becoming preferred technological partners for transnational corporations. We investigate an STP between a Scandinavian and a Chinese firm and try to explore how to gain relational competitive advantage by focusing on its two essential stages: relational rent generation...... and appropriation. Based on an explorative case study, we develop a conceptual framework that consists of process, organizational alliance factors, and coordination modes that we propose lead to relational competitive advantage....

  12. Simultaneous Determination of Arsenic, Manganese, and Selenium in Biological Materials by Neutron-Activation Analysis

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Damsgaard, Else

    1973-01-01

    A new method was developed for the simultaneous determination of arsenic, manganese, and selenium in biological material by thermal-neutron activation analysis. The use of 81 mSe as indicator for selenium permitted a reduction of activation time to 1 hr for a 1 g sample, and the possibility of loss...

  13. Outstanding visible photocatalytic activity of a new mixed bismuth titanatate material

    Energy Technology Data Exchange (ETDEWEB)

    Zambrano, P. [Instituto de Ciencia de Materiales de Sevilla, CSIC-Universidad de Sevilla, Americo Vespucio 49, 410092, Sevilla (Spain); Departamento Cristalografía, Mineralogía y Química Agrícola, Universidad de Sevilla, C/Profesor García González s/n, 41012 Sevilla (Spain); Sayagués, M.J.; Navío, J.A. [Instituto de Ciencia de Materiales de Sevilla, CSIC-Universidad de Sevilla, Americo Vespucio 49, 410092, Sevilla (Spain); Hidalgo, M.C., E-mail: carmen.hidalgo@csic.es [Instituto de Ciencia de Materiales de Sevilla, CSIC-Universidad de Sevilla, Americo Vespucio 49, 410092, Sevilla (Spain)

    2017-02-01

    Highlights: • Photocatalyst based on bismuth titanates with high visible activity. • Its visible activity as high as UV activity of TiO{sub 2} P25 for phenol degradation. • Photocatalyst is majority of phase Bi{sub 20}TiO{sub 32} with Bi{sub 4}Ti{sub 3}O{sub 12} and amorphous TiO{sub 2}. • High visible activity due to low BG, interconnected phases and high surface area. - Abstract: In this work, a new photocatalyst based on bismuth titanates with outstanding visible photocatalytic activity was prepared by a facile hydrothermal method. The synthesised material showed visible activity as high as UV activity of commercial TiO{sub 2} P25 under the same experimental conditions for phenol degradation. A wide characterisation of the photocatalyst was performed. The material was composed of three phases; majority of Bi{sub 20}TiO{sub 32} closely interconnected to Bi{sub 4}Ti{sub 3}O{sub 12} and amorphous TiO{sub 2}. The high visible activity showed by this material could be ascribed to a combination of several features; i.e. low band gap energy value (2.1 eV), a structure allowing a good separation path for visible photogenerated electron-holes pairs and a relatively high surface area. This photocatalyst appeared as a promising material for solar and visible applications of photocatalysis.

  14. Instrumental neutron and photon activation analyses of selected geochemical reference materials

    Czech Academy of Sciences Publication Activity Database

    Mizera, Jiří; Řanda, Zdeněk

    2010-01-01

    Roč. 284, č. 1 (2010), s. 157-163 ISSN 0236-5731 R&D Projects: GA AV ČR IAA300130706 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutron activation analysis * photon activation analysis * geochemical reference materials Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.777, year: 2010

  15. Instrumental neutron and photon activation analyses of selected geochemical reference materials

    Czech Academy of Sciences Publication Activity Database

    Mizera, Jiří; Řanda, Z.

    2010-01-01

    Roč. 284, č. 1 (2010), s. 157-163 ISSN 0236-5731 Institutional research plan: CEZ:AV0Z30460519 Keywords : neutron activation analysis * photon activation analysis * geochemical reference materials Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Analytical chemistry Impact factor: 0.777, year: 2010

  16. Real space mapping of ionic diffusion and electrochemical activity in energy storage and conversion materials

    Science.gov (United States)

    Kalinin, Sergei V; Balke, Nina; Kumar, Amit; Dudney, Nancy J; Jesse, Stephen

    2014-05-06

    A method and system for probing mobile ion diffusivity and electrochemical reactivity on a nanometer length scale of a free electrochemically active surface includes a control module that biases the surface of the material. An electrical excitation signal is applied to the material and induces the movement of mobile ions. An SPM probe in contact with the surface of the material detects the displacement of mobile ions at the surface of the material. A detector measures an electromechanical strain response at the surface of the material based on the movement and reactions of the mobile ions. The use of an SPM tip to detect local deformations allows highly reproducible measurements in an ambient environment without visible changes in surface structure. The measurements illustrate effective spatial resolution comparable with defect spacing and well below characteristic grain sizes of the material.

  17. Gain optimization method of a DQW superluminescent diode with broad multi-state emission

    KAUST Repository

    Dimas, Clara E.

    2010-01-01

    Optimizing gain through systematic methods of varying current injection schemes analytically is significant to maximize experimentally device yield and evaluation. Various techniques are used to calculate the amplified spontaneous emission (ASE) gain for light emitting devices consisting of single-section and multiple-sections of even length. Recently double quantum well (DQW) superluminescent diodes (SLD) have shown a broad multi-state emission due to mutlielectrodes of non-equal lengths and at high non-equal current densities. In this study, we adopt an improved method utilizing an ASE intensity ratio to calibrate a gain curve based on the sum of the measured ASE spectra to efficiently estimate the gain. Although the laser gain for GaAs/AlGaAs material is well studied, the ASE gain of SLD devices has not been systematically studied particular to further explain the multiple-state emission observed in fabricated devices. In addition a unique gain estimate was achieved where the excited state gain clamps prior to the ground state due to approaching saturation levels. In our results, high current densities in long sectioned active regions achieved sufficient un-truncated gain that show evidence of excited state emission has been observed.

  18. NOMAGE4 activities 2011. Part I, Nordic Nuclear Materials Forum for Generation IV Reactors: Status and activities in 2011

    International Nuclear Information System (INIS)

    Van Nieuwenhove, R.

    2012-01-01

    A network for materials issues has been initiated in 2009 within the Nordic countries. The original objectives of the Generation IV Nordic Nuclear Materials Forum (NOMAGE4) were to form the basis of a sustainable forum for Gen-IV issues, especially focusing on fuels, cladding, structural materials and coolant interaction. Over the last years, other issues such as reactor physics, thermal hydraulics, safety and waste have gained in importance (within the network) and therefore the scope of the forum has been enlarged and a more appropriate and more general name, NORDIC-GEN4, has been chosen for the forum. Further, the interaction with non-Nordic countries (such as The Netherlands (JRC, NRG) and Czech Republic (CVR)) will be increased. Within the NOMAGE4 project, a seminar was organized by IFE-Halden during 31 October - 1 November 2011. The seminar attracted 65 participants from 12 countries. The seminar provided a forum for exchange of information, discussion on future research reactor needs and networking of experts on Generation IV reactor concepts. The participants could also visit the Halden reactor site and the workshop. (Author)

  19. NOMAGE4 activities 2011. Part I, Nordic Nuclear Materials Forum for Generation IV Reactors: Status and activities in 2011

    Energy Technology Data Exchange (ETDEWEB)

    Van Nieuwenhove, R. (Institutt for Energiteknikk, OECD Halden Reactor Project (Norway))

    2012-01-15

    A network for materials issues has been initiated in 2009 within the Nordic countries. The original objectives of the Generation IV Nordic Nuclear Materials Forum (NOMAGE4) were to form the basis of a sustainable forum for Gen-IV issues, especially focusing on fuels, cladding, structural materials and coolant interaction. Over the last years, other issues such as reactor physics, thermal hydraulics, safety and waste have gained in importance (within the network) and therefore the scope of the forum has been enlarged and a more appropriate and more general name, NORDIC-GEN4, has been chosen for the forum. Further, the interaction with non-Nordic countries (such as The Netherlands (JRC, NRG) and Czech Republic (CVR)) will be increased. Within the NOMAGE4 project, a seminar was organized by IFE-Halden during 31 October - 1 November 2011. The seminar attracted 65 participants from 12 countries. The seminar provided a forum for exchange of information, discussion on future research reactor needs and networking of experts on Generation IV reactor concepts. The participants could also visit the Halden reactor site and the workshop. (Author)

  20. Corrosion susceptibility study of candidate pin materials for ALTC (active lithium/thionyl chloride) batteries. [Active lithium/thionyl chloride

    Energy Technology Data Exchange (ETDEWEB)

    Bovard, F.S.; Cieslak, W.R.

    1987-09-01

    (ALTC = active lithium/thionyl chloride.) We have investigated the corrosion susceptibilities of eight alternate battery pin materials in 1.5M LiAlCl/sub 4//SOCl/sub 2/ electrolyte using ampule exposure and electrochemical tests. The thermal expansion coefficients of these candidate materials are expected to match Sandia-developed Li-corrosion resistant glasses. The corrosion resistances of the candidate materials, which included three stainless steels (15-5 PH, 17-4 PH, and 446), three Fe-Ni glass sealing alloys (Kovar, Alloy 52, and Niromet 426), a Ni-based alloy (Hastelloy B-2) and a zirconium-based alloy (Zircaloy), were compared to the reference materials Ni and 316L SS. All of the candidate materials showed some evidence of corrosion and, therefore, did not perform as well as the reference materials. The Hastelloy B-2 and Zircaloy are clearly unacceptable materials for this application. Of the remaining alternate materials, the 446 SS and Alloy 52 are the most promising candidates.

  1. Fundamental Limitations to Gain Enhancement in Periodic Media and Waveguides

    DEFF Research Database (Denmark)

    Grgic, Jure; Ott, Johan Raunkjær; Wang, Fengwen

    2012-01-01

    A common strategy to compensate for losses in optical nanostructures is to add gain material in the system. By exploiting slow-light effects it is expected that the gain may be enhanced beyond its bulk value. Here we show that this route cannot be followed uncritically: inclusion of gain inevitably...

  2. Prompt gamma activation analysis (PGAA) and short-lived neutron activation analysis (NAA) applied to the characterization of legacy materials

    International Nuclear Information System (INIS)

    English, G.A.; Firestone, R.B.; Perry, D.L.; Reijonen, J.P.; Ka-Ngo Leung; Garabedian, G.F.; Molnar, G.L.; Revay, Zs.

    2008-01-01

    Without quality historical records that provide the composition of legacy materials, the elemental and/or chemical characterization of such materials requires a manual analytical strategy that may expose the analyst to unknown toxicological hazards. In addition, much of the existing legacy inventory also incorporates radioactivity, and, although radiological composition may be determined by various nuclear-analytical methods, most importantly, gamma-spectroscopy, current methods of chemical characterization still require direct sample manipulation, thereby presenting special problems with broad implications for both the analyst and the environment. Alternately, prompt gamma activation analysis (PGAA) provides a 'single-shot' in-situ, non-destructive method that provides a complete assay of all major entrained elemental constituents. Additionally, neutron activation analysis (NAA) using short-lived activation products complements PGAA and is especially useful when NAA activation surpasses the PGAA in elemental sensitivity. (author)

  3. Prompt gamma activation analysis (PGAA) and short-lived neutron activation analysis (NAA) applied to the characterization of legacy materials

    International Nuclear Information System (INIS)

    Firestone, Richard B; English, G.A.; Firestone, R.B.; Perry, D.L.; Reijonen, J.P.; Leung, Ka-Ngo; Garabedian, G.F.; Molnar, G.L.; Revay, Zs.

    2008-01-01

    Without quality historical records that provide the composition of legacy materials, the elemental and/or chemical characterization of such materials requires a manual analytical strategy that may expose the analyst to unknown toxicological hazards. In addition, much of the existing legacy inventory also incorporates radioactivity, and, although radiological composition may be determined by various nuclear-analytical methods, most importantly, gamma-spectroscopy, current methods of chemical characterization still require direct sample manipulation, thereby presenting special problems with broad implications for both the analyst and the environment. Alternately, prompt gamma activation analysis (PGAA) provides a 'single-shot' in-situ, non-destructive method that provides a complete assay of all major entrained elemental constituents.1-3. Additionally, neutron activation analysis (NAA) using short-lived activation products complements PGAA and is especially useful when NAA activation surpasses the PGAA in elemental sensitivity

  4. Antimicrobial activity of transition metal acid MoO3 prevents microbial growth on material surfaces

    International Nuclear Information System (INIS)

    Zollfrank, Cordt; Gutbrod, Kai; Wechsler, Peter; Guggenbichler, Josef Peter

    2012-01-01

    Serious infectious complications of patients in healthcare settings are often transmitted by materials and devices colonised by microorganisms (nosocomial infections). Current strategies to generate material surfaces with an antimicrobial activity suffer from the consumption of the antimicrobial agent and emerging multidrug-resistant pathogens amongst others. Consequently, materials surfaces exhibiting a permanent antimicrobial activity without the risk of generating resistant microorganisms are desirable. This publication reports on the extraordinary efficient antimicrobial properties of transition metal acids such as molybdic acid (H 2 MoO 4 ), which is based on molybdenum trioxide (MoO 3 ). The modification of various materials (e.g. polymers, metals) with MoO 3 particles or sol–gel derived coatings showed that the modified materials surfaces were practically free of microorganisms six hours after contamination with infectious agents. The antimicrobial activity is based on the formation of an acidic surface deteriorating cell growth and proliferation. The application of transition metal acids as antimicrobial surface agents is an innovative approach to prevent the dissemination of microorganisms in healthcare units and public environments. Highlights: ► The presented modifications of materials surfaces with MoO 3 are non-cytotoxic and decrease biofilm growth and bacteria transmission. ► The material is insensitive towards emerging resistances of bacteria. ► Strong potential to reduce spreading of infectious agents on inanimate surfaces.

  5. Alkali-activated binders: a review : part 2. about materials and binders manufacture

    OpenAIRE

    Torgal, Fernando Pacheco; Gomes, J. P. Castro; Jalali, Said

    2008-01-01

    This paper summarizes current knowledge about alkali-activated binders, by reviewing previously published work. As it is shown in Part 1, alkali-activated binders have emerged as an alternative to (ordinary Portland cement) OPC binders, which seem to have superior durability and environmental impact. The subjects of Part 2 of this paper are prime materials, alkaline activators, additives, curing type and constituents mixing order. Practical problems and theoretical questions are discussed. To...

  6. Prismatic louver active façades for natural illumination and thermal energy gain in high-rise and commercial buildings

    Science.gov (United States)

    Vlachokostas, A.; Volkmann, C.; Madamopoulos, N.

    2013-06-01

    High-rise and commercial buildings in urban centers present a great challenge in terms of their energy consumption. Due to maximization of rentable square footage, the preferred urban façade system over the past 50 years has been the "curtain wall", only a few inches thick and comprised of modular steel or aluminum framing and predominant glass infills. The perceived Achilles heel of these modern glass façade systems is their thermal inefficiency: They are inadequate thermal barriers and exhibit excessive solar gain. The excessive solar gain has a negative impact on lighting and cooling loads of the entire building. This negative impact will be further exacerbated with rising energy costs. However, rather than view the glass façade's uncontrolled solar gain merely as a weakness contributing to higher energy consumption, the condition could indeed be considered as related to an energy solution. These glass façades can be retrofitted to operate as a provider of daylight and energy for the rest of the building, taking advantage of the overexposure to the sun. With today's technology, the sun's abundant renewable energy can be the driving force for the energy transition of these building envelopes. Illumination, thermal energy, and electricity production can be directly supplied from the sun, and when correctly and efficiently managed, they can lead to a significantly less energy-intensive building stock. We propose a multi-purpose, prismatic, louver-based façade to perform both daylight and thermal energy harvesting with a goal of offering a better daylight environment for the occupants, and reduce the energy consumption and carbon footprint of the building. While decentralized air-conditioning units are commonly accepted as façade "plug-ins", such decentralization could be utilized with more benefits by passively managing the interior space conditions, without using any extra power. Just as living organisms respond and adapt to the environmental changes in

  7. Analyses of the activation of near term fusion reactor compound materials

    International Nuclear Information System (INIS)

    Lengar, I.

    2007-01-01

    One of the important questions that still have to be solved for the next generation fusion reactors is the choice of the material to be used for the first wall. An important criteria is low activation due to neutron bombardment from the plasma. One of the promising materials is the SiC/SiC composite. Its main elemental constituents, namely the C and Si, have very good activation characteristics. The main contribution to activity arises, however, from trace elements, which are needed in the sintering process and remain in the material afterwards. Before the preparation process of the material, the activation characteristics of individual constituents are needed. The activation properties of the whole sample could than be estimated by summing the weighted properties of individual constituents. The activity of a particular trace element is, however, not necessarily dependent only on the percentage of the element in the sample, but also on the presence of other elements in the compound due to the charge particle production and/or (n, 2n) reactions. The extension of this effect is investigated and to what extent individual calculations, performed for a single element, mimic the real situation. Further the activation characteristic for several possible sintering aid elements is theoretically investigated with the use of the FISPACT inventory code. (author)

  8. Activated Carbon-Fly Ash-Nanometal Oxide Composite Materials: Preparation, Characterization, and Tributyltin Removal Efficiency

    Directory of Open Access Journals (Sweden)

    Olushola S. Ayanda

    2013-01-01

    Full Text Available The physicochemical properties, nature, and morphology of composite materials involving activated carbon, fly ash, nFe3O4, nSiO2, and nZnO were investigated and compared. Nature and morphology characterizations were carried out by means of scanning electron and transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. Other physicochemical characterizations undertaken were CNH analysis, ash content, pH, point of zero charge, and surface area and porosity determination by BET. Experimental results obtained revealed that activated carbon, nSiO2, activated carbon-fly ash, activated carbon-fly ash-nFe3O4, activated carbon-fly ash-nSiO2, and activated carbon-fly ash-nZnO composite materials exhibited net negative charge on their surfaces while fly ash, nFe3O4, and nZnO possessed net positive charge on their surfaces. Relatively higher removal efficiency (>99% of TBT was obtained for all the composite materials compared to their respective precursors except for activated carbon. These composite materials therefore offer great potential for the remediation of TBT in wastewaters.

  9. Deuteron and neutron induced activation in the Eveda accelerator materials: implications for the accelerator maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M.; Sanz, J.; Garcia, N.; Cabellos, O. [Madrid Univ. Politecnica, C/ Jose Gutierrez Abascal, lnstituto de Fusion Nuclear (Spain); Sauvan, R. [Universidad Nacional de Educacion a Distancia (UNED), Madrid (Spain); Moreno, C.; Sedano, L.A. [CIEMAT-Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, Association Euratom-CIEMAT, Madrid (Spain)

    2007-07-01

    Full text of publication follows: The IFMIF (International Fusion Materials Irradiation Facility) is an accelerator-based DLi neutron source designed to test fusion reactor candidate materials for high fluence neutrons. Before deciding IFMIF construction, an engineering design and associated experimental data acquisition, defined as EVEDA, has been proposed. Along the EVEDA accelerator, deuteron beam losses collide with the accelerator materials, producing activation and consequent radiations responsible of dose. Calculation of the dose rates in the EVEDA accelerator room is necessary in order to analyze the feasibility for manual maintenance. Dose rates due to the activation produced by the deuteron beam losses interaction with the accelerator materials, will be calculated with the ACAB activation code, using EAF2007 library for deuteron activation cross-sections. Also, dose rates from the activation induced by the neutron source produced by the interaction of deuteron beam losses with the accelerator materials and the deuterium implanted in the structural lattice, will be calculated with the SRIM2006, TMAP7, DROSG2000/NEUYIE, MCNPX and ACAB codes. All calculations will be done for the EVEDA accelerator with the room temperature DTL structure, which is based on copper cavities for the DTL. Some calculations will be done for the superconducting DTL structure, based on niobium cavities for the DTL working at cryogenic temperature. Final analysis will show the dominant mechanisms and major radionuclides contributing to the surface dose rates. (authors)

  10. Four-electron transfer tandem tetracyanoquinodimethane for cathode-active material in lithium secondary battery

    Science.gov (United States)

    Kurimoto, Naoya; Omoda, Ryo; Mizumo, Tomonobu; Ito, Seitaro; Aihara, Yuichi; Itoh, Takahito

    2018-02-01

    Quinoid compounds are important candidates of organic active materials for lithium-ion batteries. However, its high solubility to organic electrolyte solutions and low redox potential are known as their major drawbacks. To circumvent these issues, we have designed and synthesized a tandem-tetracyanoquinonedimethane type cathode-active material, 11,11,12,12,13,13,14,14-octacyano-1,4,5,8-anthradiquinotetramethane (OCNAQ), that has four redox sites per molecule, high redox potential and suppressed solubility to electrolyte solution. Synthesized OCNAQ has been found to have two-step redox reactions by cyclic voltammetry, and each step consists of two-electron reactions. During charge-discharge tests using selected organic cathode-active materials with a lithium metal anode, the cell voltages obtained from OCNAQ are higher than those for 11,11-dicyanoanthraquinone methide (AQM) as expected, due to the strong electron-withdrawing effect of the cyano groups. Unfortunately, even with the use of the organic active material, the issue of dissolution to the electrolyte solution cannot be suppressed completely; however, appropriate choice of the electrolyte solutions, glyme-based electrolyte solutions in this study, give considerable improvement of the cycle retention (98% and 56% at 10 and 100 cycles at 0.5C, respectively). The specific capacity and energy density obtained in this study are 206 mAh g-1 and 554 mWh g-1 with respect to the cathode active material.

  11. A SCALE-UP Mock-Up: Comparison of Student Learning Gains in High- and Low-Tech Active-Learning Environments

    Science.gov (United States)

    Soneral, Paula A. G.; Wyse, Sara A.

    2017-01-01

    Student-centered learning environments with upside-down pedagogies (SCALE-UP) are widely implemented at institutions across the country, and learning gains from these classrooms have been well documented. This study investigates the specific design feature(s) of the SCALE-UP classroom most conducive to teaching and learning. Using pilot survey data from instructors and students to prioritize the most salient SCALE-UP classroom features, we created a low-tech “Mock-up” version of this classroom and tested the impact of these features on student learning, attitudes, and satisfaction using a quasi-­experimental setup. The same instructor taught two sections of an introductory biology course in the SCALE-UP and Mock-up rooms. Although students in both sections were equivalent in terms of gender, grade point average, incoming ACT, and drop/fail/withdraw rate, the Mock-up classroom enrolled significantly more freshmen. Controlling for class standing, multiple regression modeling revealed no significant differences in exam, in-class, preclass, and Introduction to Molecular and Cellular Biology Concept Inventory scores between the SCALE-UP and Mock-up classrooms. Thematic analysis of student comments highlighted that collaboration and whiteboards enhanced the learning experience, but technology was not important. Student satisfaction and attitudes were comparable. These results suggest that the benefits of a SCALE-UP experience can be achieved at lower cost without technology features. PMID:28213582

  12. Fractional-order active fault-tolerant force-position controller design for the legged robots using saturated actuator with unknown bias and gain degradation

    Science.gov (United States)

    Farid, Yousef; Majd, Vahid Johari; Ehsani-Seresht, Abbas

    2018-05-01

    In this paper, a novel fault accommodation strategy is proposed for the legged robots subject to the actuator faults including actuation bias and effective gain degradation as well as the actuator saturation. First, the combined dynamics of two coupled subsystems consisting of the dynamics of the legs subsystem and the body subsystem are developed. Then, the interaction of the robot with the environment is formulated as the contact force optimization problem with equality and inequality constraints. The desired force is obtained by a dynamic model. A robust super twisting fault estimator is proposed to precisely estimate the defective torque amplitude of the faulty actuator in finite time. Defining a novel fractional sliding surface, a fractional nonsingular terminal sliding mode control law is developed. Moreover, by introducing a suitable auxiliary system and using its state vector in the designed controller, the proposed fault-tolerant control (FTC) scheme guarantees the finite-time stability of the closed-loop control system. The robustness and finite-time convergence of the proposed control law is established using the Lyapunov stability theory. Finally, numerical simulations are performed on a quadruped robot to demonstrate the stable walking of the robot with and without actuator faults, and actuator saturation constraints, and the results are compared to results with an integer order fault-tolerant controller.

  13. Spectral singularities, threshold gain, and output intensity for a slab laser with mirrors

    Science.gov (United States)

    Doğan, Keremcan; Mostafazadeh, Ali; Sarısaman, Mustafa

    2018-05-01

    We explore the consequences of the emergence of linear and nonlinear spectral singularities in TE modes of a homogeneous slab of active optical material that is placed between two mirrors. We use the results together with two basic postulates regarding the behavior of laser light emission to derive explicit expressions for the laser threshold condition and output intensity for these modes of the slab and discuss their physical implications. In particular, we reveal the details of the dependence of the threshold gain and output intensity on the position and properties of the mirrors and on the real part of the refractive index of the gain material.

  14. Waste reduction by re-use of low activated material - 16035

    International Nuclear Information System (INIS)

    Ehrlicher, Ulrich; Pauli, Heinz

    2009-01-01

    A multidisciplinary institute, equipped with research reactors and accelerator-driven research installations produces and, in the case of PSI, collects radioactive waste on one hand and requires material, especially for shielding purpose, on the other hand. The legislative framework for radiation protection, financial reasons and limited storage capacity strongly force Paul Scherrer Institute and comparable facilities to minimize radioactive waste. Besides free release of inactive components, recycling and re-use of low-level radioactive material in controlled areas are the best means for waste minimization. The re-use of slightly activated steel plates as a shielding material and the recycling of irradiated reactor graphite as a filling material embedded in mortar may give examples and encouragement for similar activities. Besides the advantages for radiation protection, the financial benefit can be measured in millions of dollars. (authors)

  15. Optical properties of nanowire metamaterials with gain

    DEFF Research Database (Denmark)

    Isidio de Lima, Joaquim Junior; Adam, Jost; Rego, Davi

    2016-01-01

    The transmittance, reflectance and absorption of a nanowire metamaterial with optical gain are numerically simulated and investigated. It is assumed that the metamaterial is represented by aligned silver nanowires embedded into a semiconductor matrix, made of either silicon or gallium phosphide....... The gain in the matrix is modeled by adding a negative imaginary part to the dielectric function of the semiconductor. It is found that the optical coefficients of the metamaterial depend on the gain magnitude in a non-trivial way: they can both increase and decrease with gain depending on the lattice...... constant of the metamaterial. This peculiar behavior is explained by the field redistribution between the lossy metal nanowires and the amplifying matrix material. These findings are significant for a proper design of nanowire metamaterials with low optical losses for diverse applications....

  16. Instrumental neutron activation analysis of phosphorus in biological materials by Bremsstrahlung measurement

    International Nuclear Information System (INIS)

    Bajo, S.; Wyttenbach, A.

    1986-12-01

    The determination of phosphorus in biological materials by instrumental neutron activation via the reaction 31 P (n,γ) 32 P is described. The Bremsstrahlung produced by 32 P is measured in a well-type NaI(Tl) detector. The samples are measured within the polyethylene irradiation container with no changes between irradiation and measurement. The sources of error were studied and the proposed method was applied to the determination of phosphorus in ten internationally certified materials. (author)

  17. Chemical signal activation of an organocatalyst enables control over soft material formation.

    Science.gov (United States)

    Trausel, Fanny; Maity, Chandan; Poolman, Jos M; Kouwenberg, D S J; Versluis, Frank; van Esch, Jan H; Eelkema, Rienk

    2017-10-12

    Cells can react to their environment by changing the activity of enzymes in response to specific chemical signals. Artificial catalysts capable of being activated by chemical signals are rare, but of interest for creating autonomously responsive materials. We present an organocatalyst that is activated by a chemical signal, enabling temporal control over reaction rates and the formation of materials. Using self-immolative chemistry, we design a deactivated aniline organocatalyst that is activated by the chemical signal hydrogen peroxide and catalyses hydrazone formation. Upon activation of the catalyst, the rate of hydrazone formation increases 10-fold almost instantly. The responsive organocatalyst enables temporal control over the formation of gels featuring hydrazone bonds. The generic design should enable the use of a large range of triggers and organocatalysts, and appears a promising method for the introduction of signal response in materials, constituting a first step towards achieving communication between artificial chemical systems.Enzymes regulated by chemical signals are common in biology, but few such artificial catalysts exist. Here, the authors design an aniline catalyst that, when activated by a chemical trigger, catalyses formation of hydrazone-based gels, demonstrating signal response in a soft material.

  18. Relative contributions of energy expenditure on physical activity, body composition and weight gain to the evolution of impaired glucose tolerance to Frank diabetes. Highlights and achievements

    International Nuclear Information System (INIS)

    Adeyemo, A.A.

    2002-01-01

    The effect of obesity on glucose intolerance is a mixture of the impact of body composition on glucose-insulin relationships as well as the modulation of this metabolism by physical activity. Populations of the African diaspora in the Caribbean and the United States have higher levels of obesity, glucose intolerance and diabetes than the ancestral population in West Africa. This is most likely a consequence of lifestyle changes, including an apparent decline in physical activity and dietary changes

  19. Relative contributions of energy expenditure on physical activity, body composition and weight gain to the evolution of impaired glucose tolerance to Frank diabetes. Highlights and achievements

    Energy Technology Data Exchange (ETDEWEB)

    Adeyemo, A A [Department of Paediatrics and Institute of Child Health, University College Hospital, Ibadan (Nigeria)

    2002-07-01

    The effect of obesity on glucose intolerance is a mixture of the impact of body composition on glucose-insulin relationships as well as the modulation of this metabolism by physical activity. Populations of the African diaspora in the Caribbean and the United States have higher levels of obesity, glucose intolerance and diabetes than the ancestral population in West Africa. This is most likely a consequence of lifestyle changes, including an apparent decline in physical activity and dietary changes.

  20. Instrumental neutron activation analysis of marine sediment in-house reference material

    International Nuclear Information System (INIS)

    Nazaratul Ashifa Abdullah Salim; Mohd Suhaimi Hamzah; Mohd Suhaimi Elias; Siong, W.B.; Shamsiah Abdul Rahman; Azian Hashim; Shakirah Abdul Shukor

    2013-01-01

    Reference materials play an important role in demonstrating the quality and reliability of analytical data. The advantage of using in-house reference materials is that they provide a relatively cheap option as compared to using commercially available certified reference material (CRM) and can closely resemble the laboratory routine test sample. A marine sediment sample was designed as an in-house reference material, in the framework of quality assurance and control (QA/QC) program of the Neutron Activation Analysis (NAA) Laboratory at Nuclear Malaysia. The NAA technique was solely used for the homogeneity test of the marine sediment sample. The CRM of IAEA- Soil 7 and IAEA- SL1 (Lake Sediment) were applied in the analysis as compatible matrix based reference materials for QA purposes. (Author)

  1. The determination of plutonium alpha activity in urine, faeces and biological materials

    International Nuclear Information System (INIS)

    Bains, M.E.D.

    1963-07-01

    Methods have been developed for the determination of plutonium alpha activity in urine, faeces and biological materials. The chemical stages involved give practically complete separation of all extraneous material from the plutonium, which is electrodeposited on to a 0.5 inch stainless steel disc to produce a thin high resolution source. The limit of detection is 0.025 μμc/sample (sixteen-hour count) when the sources are counted in a small scintillator counter, but is lowest when counted in a counter which counts particles of energy 5.05-5.25 MeV only, and which therefore discriminates against small quantities of α-active materials introduced with the reagents in the final electrodeposition stage of the process. (Any such alpha activity may readily be identified by alpha pulse height analysis). (author)

  2. A SCALE-UP Mock-Up: Comparison of Student Learning Gains in High- and Low-Tech Active-Learning Environments.

    Science.gov (United States)

    Soneral, Paula A G; Wyse, Sara A

    2017-01-01

    Student-centered learning environments with upside-down pedagogies (SCALE-UP) are widely implemented at institutions across the country, and learning gains from these classrooms have been well documented. This study investigates the specific design feature(s) of the SCALE-UP classroom most conducive to teaching and learning. Using pilot survey data from instructors and students to prioritize the most salient SCALE-UP classroom features, we created a low-tech "Mock-up" version of this classroom and tested the impact of these features on student learning, attitudes, and satisfaction using a quasi--experimental setup. The same instructor taught two sections of an introductory biology course in the SCALE-UP and Mock-up rooms. Although students in both sections were equivalent in terms of gender, grade point average, incoming ACT, and drop/fail/withdraw rate, the Mock-up classroom enrolled significantly more freshmen. Controlling for class standing, multiple regression modeling revealed no significant differences in exam, in-class, preclass, and Introduction to Molecular and Cellular Biology Concept Inventory scores between the SCALE-UP and Mock-up classrooms. Thematic analysis of student comments highlighted that collaboration and whiteboards enhanced the learning experience, but technology was not important. Student satisfaction and attitudes were comparable. These results suggest that the benefits of a SCALE-UP experience can be achieved at lower cost without technology features. © 2017 P. A. G. Soneral and S. A. Wyse. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  3. Net energy gain from DT fusion

    International Nuclear Information System (INIS)

    Buende, R.

    1985-01-01

    The net energy which can be gained from an energy raw material by means of a certain conversion system is deduced as the figure-of-merit which adequately characterizes the net energy balance of utilizing an energy source. This potential net energy gain is determined for DT fusion power plants. It is represented as a function of the degree of exploitation of the energy raw material lithium ore and is compared with the net energy which can be gained with LW and FBR power plants by exploiting uranium ore. The comparison clearly demonstrates the net energetic advantage of DT fusion. A sensitivity study shows that this holds even if the energy expenditure for constructing and operating is drastically increased

  4. Estimated neutron-activation data for TFTR. Part II. Biological dose rate from sample-materials activation

    International Nuclear Information System (INIS)

    Ku, L.; Kolibal, J.G.

    1982-06-01

    The neutron induced material activation dose rate data are summarized for the TFTR operation. This report marks the completion of the second phase of the systematic study of the activation problem on the TFTR. The estimations of the neutron induced activation dose rates were made for spherical and slab objects, based on a point kernel method, for a wide range of materials. The dose rates as a function of cooling time for standard samples are presented for a number of typical neutron spectrum expected during TFTR DD and DT operations. The factors which account for the variations of the pulsing history, the characteristic size of the object and the distance of observation relative to the standard samples are also presented

  5. The effect of a self-constructed material on children’s physical activity during recess

    Directory of Open Access Journals (Sweden)

    Antonio Méndez-Giménez

    Full Text Available ABSTRACT OBJECTIVE To analyze whether an intervention supported by free play with a self-constructed material increases the level of physical activity of students during recess. METHODS The participants were 166 children of third to sixth grade, between nine and 12 years old (average = 10.64; SS = 1.13. An experimental project was conducted with pre-test and post-test measurement, and a control group. Experimental group participants built cardboard paddles (third and fourth and flying rings (fifth and sixth, a material they used freely for one week during recess. ActiGraph-GT3X accelerometers were used to measure physical activity. An ANOVA of repeated measures was used to find differences between groups and genders. RESULTS Significant intervention effects were found in the analyzed variables: sedentary activity (F = 38.19; p < 0.01, light (F = 76.56; p < 0.01, moderate (F = 27.44; p < 0.01, vigorous (F = 61.55; p < 0.01, and moderate and vigorous (F = 68.76; p < 0.01. Significant gender differences were shown (time × group × gender for moderate (F = 6.58; p < 0.05 and vigorous (F = 5.51; p < 0.05 activity. CONCLUSIONS The self-constructed material is effective to increase the physical activity levels of children during recess; it decreases sedentary activity and light physical activity and increases the time devoted to moderate physical activity and vigorous physical activity, both in boys and in girls. The boys had an increase in vigorous physical activity and the girls in moderate physical activity. Due to its low cost, this strategy is recommended for administrators and teachers to increase the physical activity of children during recess.

  6. Relative contributions of energy expenditure on physical activity, body composition and weight gain to the evolution of impaired glucose tolerance to Frank diabetes. Highlights and achievements

    International Nuclear Information System (INIS)

    Forrester, T.

    2002-01-01

    There is a gradient of diabetes prevalence among populations of the African Diaspora. HYPOTHESIS: The risk of diabetes in transitional populations of the African diaspora is directly related to the rate of anthropornetric change and physical activity. AIMS: - To determine whether risk of incident diabetes and impaired glucose tolerance is related to physical activity in two populations of the African Diaspora with widely different levels of obesity; - To determine whether risk of incident diabetes and impaired glucose tolerance is related to rate of rise in body weight and change in body composition

  7. Accessibility evaluation of the IFMIF liquid lithium loop considering activated erosion/corrosion materials deposition

    International Nuclear Information System (INIS)

    Nakamura, H.; Takemura, M.; Yamauchi, M.; Fischer, U.; Ida, M.; Mori, S.; Nishitani, T.; Simakov, S.; Sugimoto, M.

    2005-01-01

    This paper presents an evaluation of accessibility of the Li loop piping considering activated corrosion product. International Fusion Materials Irradiation Facility (IFMIF) is a deuteron-lithium (Li) stripping reaction neutron source for fusion materials testing. Target assembly and back wall are designed as fully remote maintenance component. Accessibility around the Li loop piping will depend on activation level of the deposition materials due to the back wall erosion/corrosion process under liquid Li flow. Activation level of the corrosion products coming from the AISI 316LN back wall is calculated by the ACT-4 of the THIDA-2 code system. The total activities after 1 day, 1 week, 1 month and 1 year cooling are 3.1 x 10 14 , 2.8 x 10 14 , 2.3 x 10 14 and 7.5 x 10 13 Bq/kg, respectively. Radiation dose rate around the Li loop pipe is calculated by QAD-CGGP2R code. Activated area of the back wall is 100 cm 2 . Corrosion rate is assumed 1 μm/year. When 10% of the corrosion material is supposed to be deposited on the inner surface of the pipe, the dose rate is calculated to be less than a permissible level of 10 μSv/h for hands-on maintenance, therefore, the maintenance work is assessed to be possible

  8. Central gain control in tinnitus and hyperacusis

    Directory of Open Access Journals (Sweden)

    Benjamin D Auerbach

    2014-10-01

    Full Text Available Sensorineural hearing loss induced by noise or ototoxic drug exposure reduces the neural activity transmitted from the cochlea to the central auditory system. Despite a reduced cochlear output, neural activity from more central auditory structures is paradoxically enhanced at suprathreshold intensities. This compensatory increase in the central auditory activity in response to the loss of sensory input is referred to as central gain enhancement. Enhanced central gain is hypothesized to be a potential mechanism that gives rise to hyperacusis and tinnitus, two debilitating auditory perceptual disorders that afflict millions of individuals. This review will examine the evidence for gain enhancement in the central auditory system in response to cochlear damage. Further, it will address the potential cellular and molecular mechanisms underlying this enhancement and discuss the contribution of central gain enhancement to tinnitus and hyperacusis. Current evidence suggests that multiple mechanisms with distinct temporal and spectral profiles are likely to contribute to central gain enhancement. Dissecting the contributions of these different mechanisms at different levels of the central auditory system is essential for elucidating the role of central gain enhancement in tinnitus and hyperacusis and, most importantly, the development of novel treatments for these disorders.

  9. Central Gain Control in Tinnitus and Hyperacusis

    Science.gov (United States)

    Auerbach, Benjamin D.; Rodrigues, Paulo V.; Salvi, Richard J.

    2014-01-01

    Sensorineural hearing loss induced by noise or ototoxic drug exposure reduces the neural activity transmitted from the cochlea to the central auditory system. Despite a reduced cochlear output, neural activity from more central auditory structures is paradoxically enhanced at suprathreshold intensities. This compensatory increase in the central auditory activity in response to the loss of sensory input is referred to as central gain enhancement. Enhanced central gain is hypothesized to be a potential mechanism that gives rise to hyperacusis and tinnitus, two debilitating auditory perceptual disorders that afflict millions of individuals. This review will examine the evidence for gain enhancement in the central auditory system in response to cochlear damage. Further, it will address the potential cellular and molecular mechanisms underlying this enhancement and discuss the contribution of central gain enhancement to tinnitus and hyperacusis. Current evidence suggests that multiple mechanisms with distinct temporal and spectral profiles are likely to contribute to central gain enhancement. Dissecting the contributions of these different mechanisms at different levels of the central auditory system is essential for elucidating the role of central gain enhancement in tinnitus and hyperacusis and, most importantly, the development of novel treatments for these disorders. PMID:25386157

  10. Corrosion susceptibility study of candidate pin materials for ALTC (Active Lithium/Thionyl Chloride) batteries

    Science.gov (United States)

    Bovard, Francine S.; Cieslak, Wendy R.

    1987-09-01

    The corrosion susceptibilities of eight alternate battery pin material candidates for ALTC (Active Lithium/Thionyl Chloride) batteries in 1.5M LiAlCl4/SOCl2 electrolyte have been investigated using ampule exposure and electrochemical tests. The thermal expansion coefficients of these candidate materials are expected to match Sandia-developed Li-corrosion resistant glasses. The corrosion resistances of the candidate materials, which included three stainless steels (15-5 PH, 17-4 PH, and 446), three Fe-Ni glass sealing alloys (Kovar, Alloy 52, and Niromet 426), a Ni-based alloy (Hastelloy B-2) and a zirconium-based alloy (Zircaloy), were compared to the reference materials Ni and 316L SS. All of the candidate materials showed some evidence of corrosion and, therefore, did not perform as well as the reference materials. The Hastelloy B-2 and Zircaloy are clearly unacceptable materials for this application. Of the remaining alternate materials, the 446 SS and Alloy 52 are the most promising candidates.

  11. Optical gain and gain suppression of quantum-well lasers with valence band mixing

    International Nuclear Information System (INIS)

    Ahn, D.; Chuang, S.L.

    1990-01-01

    The effects of valence band mixing on the nonlinear gains of quantum-well lasers are studied theoretically. The authors' analysis is based on the multiband effective-mass theory and the density matrix formalism with intraband relaxation taken into account. The gain and the gain-suppression coefficient of a quantum-well laser are calculated from the complex optical susceptibility obtained by the density matrix formulation with the theoretical dipole moments obtained from the multiband effective-mass theory. The calculated gain spectrum shows that there are remarkable differences (both in peak amplitude and spectral shape) between our model with valence band mixing and the conventional parabolic band model. The shape of the gain spectrum calculated by the authors' model becomes more symmetric due to intraband relaxation together with nonparabolic energy dispersions and is closer to the experimental observations when compared with the conventional method using the parabolic band model and the multiband effective-mass calculation without intraband relaxation. Both give quite asymmetric gain spectra. Optical intensity in the GaAs active region is estimated by solving rate equations for the stationary states with nonlinear gain suppression. The authors calculate the mode gain for the resonant mode including the gain suppression, which results in spectral hole burning of the gain spectrum

  12. Teacher-and child-managed academic activities in preschool and kindergarten and their influence on children's gains in emergent academic skills

    NARCIS (Netherlands)

    De Haan, Annika K E; Elbers, Ed; Leseman, Paul P M

    2014-01-01

    The aim of this study was to assess whether children's development benefited from teacher-and child-managed academic activities in the preschool and kindergarten classroom. Extensive systematic observations during four half-days in preschool (n = 8) and kindergarten (n = 8) classrooms revealed that

  13. Teacher-and Child-Managed Academic Activities in Preschool and Kindergarten and Their Influence on Children's Gains in Emergent Academic Skills

    Science.gov (United States)

    de Haan, Annika K. E.; Elbers, Ed; Leseman, Paul P. M.

    2014-01-01

    The aim of this study was to assess whether children's development benefited from teacher-and child-managed academic activities in the preschool and kindergarten classroom. Extensive systematic observations during four half-days in preschool ("n"?=?8) and kindergarten ("n"?=?8) classrooms revealed that classrooms differed in…

  14. Lifestyle intervention to improve quality of life and prevent weight gain after renal transplantation : Design of the Active Care after Transplantation (ACT) randomized controlled trial

    NARCIS (Netherlands)

    Klaassen, Gerald; Zelle, Dorien M; Navis, Gerjan J; Dijkema, Desie; Bemelman, Frederike J; Bakker, Stephan J L; Corpeleijn, Eva

    2017-01-01

    BACKGROUND: Low physical activity and reduced physical functioning are common after renal transplantation, resulting in a reduced quality of life. Another common post-transplantation complication is poor cardio-metabolic health, which plays a main role in long-term outcomes in renal transplant

  15. Incidents of illicit trafficking and other unauthorized activities involving nuclear and other radioactive materials (1993-2005)

    International Nuclear Information System (INIS)

    2010-01-01

    The confirmed incidents of illicit trafficking and other unauthorized activities involving nuclear and other radioactive materials between 1993-2005 shows that, 27% involved nuclear materials, 62% radioactive materials,7% involved both nuclear and other radioactive materials while the remainder involved other radioactive and non radioactive materials.Also 80% of nuclear material which was recovered during the same period was not reported as stolen or lost.

  16. Processing method and processing device for liquid waste containing surface active agent and radioactive material

    International Nuclear Information System (INIS)

    Nishi, Takashi; Matsuda, Masami; Baba, Tsutomu; Yoshikawa, Ryozo; Yukita, Atsushi.

    1998-01-01

    Washing liquid wastes containing surface active agents and radioactive materials are sent to a deaerating vessel. Ozone is blown into the deaerating vessel. The washing liquid wastes dissolved with ozone are introduced to a UV ray irradiation vessel. UV rays are irradiated to the washing liquid wastes, and hydroxy radicals generated by photodecomposition of dissolved ozone oxidatively decompose surface active agents contained in the washing liquid wastes. The washing liquid wastes discharged from the UV ray irradiation vessel are sent to an activated carbon mixing vessel and mixed with powdery activated carbon. The surface active agents not decomposed in the UV ray irradiation vessel are adsorbed to the activated carbon. Then, the activated carbon and washing liquid wastes are separated by an activated carbon separating/drying device. Radioactive materials (iron oxide and the like) contained in the washing liquid wastes are mostly granular, and they are separated and removed from the washing liquid wastes in the activated carbon separating/drying device. (I.N.)

  17. Post-Materialism as a Cultural Factor Influencing Entrepreneurial Activity across Nations

    OpenAIRE

    Uhlaner, L.M.; Thurik, A.R.; Hutjes, J.

    2002-01-01

    textabstractThe study of the determinants of entrepreneurship at the country level has been dominated by economic influences. The relative stability of differences in levels of entrepreneurship across coun-tries suggests that other forces such as certain institutional and/or cultural factors are at play. The objective of this paper is to explore how post-materialism explains differences in entrepreneurial activity across countries. Entrepreneurial activity is defined as the percent of a count...

  18. Experimental Observations of Nuclear Activity in Deuterated Materials Subjected to a Low-Energy Photon Beam

    Science.gov (United States)

    Steinetz, Bruce M.; Benyo, Theresa L.; Pines, Vladimir; Pines, Marianna; Forsley, Lawrence P.; Westmeyer, Paul A.; Chait, Arnon; Becks, Michael D.; Martin, Richard E.; Hendricks, Robert C.; hide

    2017-01-01

    Exposure of highly deuterated materials to a low-energy (nom. 2 MeV) photon beam resulted in nuclear activity of both the parent metals of hafnium and erbium and a witness material (molybdenum) mixed with the reactants. Gamma spectral analysis of all deuterated materials, ErD2.8+C36D74+Mo and HfD2+C36D74+Mo, showed that nuclear processes had occurred as shown by unique gamma signatures. For the deuterated erbium specimens, posttest gamma spectra showed evidence of radioisotopes of erbium ((163)Er and (171)Er) and of molybdenum ((99)Mo and (101)Mo) and by beta decay, technetium (99mTc and 101Tc). For the deuterated hafnium specimens, posttest gamma spectra showed evidence of radioisotopes of hafnium (180mHf and 181Hf) and molybdenum ((99)Mo and (101)Mo), and by beta decay, technetium ((99m)Tc and (101)Tc). In contrast, when either the hydrogenated or non-gas-loaded erbium or hafnium materials were exposed to the gamma flux, the gamma spectra revealed no new isotopes. Neutron activation materials showed evidence of thermal and epithermal neutrons. CR-39 solid-state nuclear track detectors showed evidence of fast neutrons with energies between 1.4 and 2.5 MeV and several instances of triple tracks, indicating (is) greater than 10 MeV neutrons. Further study is required to determine the mechanism causing the nuclear activity.

  19. Review of neutron activation analysis in the standardization and study of reference materials, including its application to radionuclide reference materials

    International Nuclear Information System (INIS)

    Byrne, A.R.

    1993-01-01

    Neutron activation analysis (NAA) plays a very important role in the certification of reference materials (RMs) and their characterization, including homogeneity testing. The features of the method are briefly reviewed, particularly aspects relating to its completely independent nuclear basis, its virtual freedom from blank problems, and its capacity for self-verification. This last aspect, arising from the essentially isotopic character of NAA, can be exploited by using different nuclear reactions and induced nuclides, and the possibility of employing two modes, one instrumental (nondestructive), the other radiochemical (destructive). This enables the derivation of essentially independent analytical information and the unique capacity of NAA for selfvalidation. The application of NAA to quantify natural or man-made radionuclides such as uranium, thorium, 237 Np, 129 I and 230 Th is discussed, including its advantages over conventional radiometric methods and its usefulness in providing independent data for nuclides where other confirmatory analyses are impossible, or are only recently becoming available through newer 'atom counting' techniques. Certain additional, prospective uses of NAA in the study of RMs and potential RMs are mentioned, including transmutation reactions, creation of endogenously radiolabelled matrices for production and study of RMs (such as dissolution and leaching tests, use as incorporated radiotracers for chemical recovery correction), and the possibility of molecular activation analysis for specification. (orig.)

  20. Material activation assessment for waste analysis of the EU design of RC/RTO ITER

    International Nuclear Information System (INIS)

    Cambi, G.; Cepraga, D.G.; Frisoni, M.

    2001-01-01

    This paper presents the results of Sn radiation transport and activation calculations related to the ITER RC/RTO EU-I design, performed in support of safety and waste management analyses. The activation characteristics (included the clearance levels) have been estimated for the different materials/zones of the equatorial plane up to 10 5 years after plasma operations. The Bonami-XSDNRPM sequence of the Scale 4.4 code system (using Vitamin-ENEA library, based on ENDF/B-VI data) has been used for radiation transport analyses. The ANITA-4M activation code (with FENDL/A-2 and FENDL/D-2 activation and decay data libraries) is used for the activation calculation. The unconditional clearance level data library is based on IAEA-TECDOC-855. First, a sensitivity analysis to optimise the radial spatial meshing for the neutron flux distribution evaluation and, accordingly, for the activation calculation, has been performed. Then, the clearance indexes of vessel and ex-vessel zones/materials have been calculated. The results are presented and discussed. A design option that considers copper instead of superconductor material for TFC winding pack has also been considered and assessed

  1. Leading Gainful Employment Metric Reporting

    Science.gov (United States)

    Powers, Kristina; MacPherson, Derek

    2016-01-01

    This chapter will address the importance of intercampus involvement in reporting of gainful employment student-level data that will be used in the calculation of gainful employment metrics by the U.S. Department of Education. The authors will discuss why building relationships within the institution is critical for effective gainful employment…

  2. Aluminium-gold reference material for the k0-standardisation of neutron activation analysis

    International Nuclear Information System (INIS)

    Ingelbrecht, C.; Peetermans, F.; Corte, F. de; Wispelaere, A. de; Vandecasteele, C.; Courtijn, E.; Hondt, P. d'

    1991-01-01

    Gold is an excellent comparator material for the k 0 -standardisation of neutron activation analysis because of its convenient and well defined nuclear properties. The most suitable form for a reference material is a dilute aluminium-gold alloy, for which the self-shielding effect for neutrons is small. Castings of composition Al-0.1 wt.% Au were prepared by crucible-less levitation melting, which gives close control of ingot composition with minimal contamination of the melt. The alloy composition was checked using induction-coupled plasma source emission spectrometry. The homogeneity of the alloy was measured by neutron activation analysis and a relative standard deviation of the gold content of 0.30% was found (10 mg samples). Metallography revealed a homogeneous distribution of AuAl 2 particles. The alloy was certified as Reference Materials CBNM-530, with certified gold mass fraction 0.100±0.002 wt.%. (orig.)

  3. Low-activation structural ceramic composites for fusion power reactors: materials development and main design issues

    International Nuclear Information System (INIS)

    Perez, A.S.; Le Bars, N.; Giancarli, L.; Proust, E.; Salavy, J.F.

    1994-01-01

    Development of advanced Low-Activation Materials (LAMs) with favourable short-term activation characteristics is discussed, for the use as structural materials in a fusion power reactor (in order to reduce the risk associated with a major accident, in particular those related with radio-isotopes release in the environment), and to try to approach the concept of an inherently safe reactor. LA Ceramics Composites (LACCs) are the most promising LAMs because of their relatively good thermo-mechanical properties. At present, SiC/SiC composite is the only LACC considered by the fusion community, and therefore is the one having the most complete data base. The preliminary design of a breeding blanket using SiC/SiC as structural material indicated that significant improvement of its thermal conductivity is required. (author) 11 refs.; 3 figs

  4. Activation of TZM and stainless steel divertor materials in the NET fusion machine

    International Nuclear Information System (INIS)

    Cepraga, D.G.; Menapace, E.; Cambi, G.; Ciattaglia, S.; Petrizzi, L.; Cavallone, G.; Costa, M.; Broccoli, U.

    1994-01-01

    This paper presents the results of the activation and decay heat calculations for the divertor plate materials of the Next European Torus (NET). The basic option assessed enables molybdenum alloy TZM and AISI 316L as material for divertor cooling channels. Burn time, effective irradiation time history, and fluence dependence on activation, decay heat, and contact dose is assessed. Impact of the material impurity level on the radioactive inventory is also investigated. The ANITA code is used, with updated cross sections and decay data libraries based on EFF-2 and EAF-3 evaluation files. The flux-weighted spectrum provided by XSDRNPM or ANISN 1-D codes has been used. The real NET geometry was modelled with the 3-D MCNP Monte Carlo neutron transport code. ((orig.))

  5. Activation of TZM and stainless steel divertor materials in the NET fusion machine

    Energy Technology Data Exchange (ETDEWEB)

    Cepraga, D G [ENEA, INN-FIS, 8 Viale Ercolani, 40138, Bologna (Italy); Menapace, E [ENEA, INN-FIS, 8 Viale Ercolani, 40138, Bologna (Italy); Cambi, G [Bologna University, Physics Department, 33 Via Irnerio, 40126, Bologna (Italy); Ciattaglia, S [ENEA, NUC-FUS, 27 Via E. Fermi, 00044, Frascati (Italy); Petrizzi, L [ENEA, NUC-FUS, 27 Via E. Fermi, 00044, Frascati (Italy); Cavallone, G [NIER S.r.l., 16 Via S. Stefano, 40125, Bologna (Italy); Costa, M [NIER S.r.l., 16 Via S. Stefano, 40125, Bologna (Italy); Broccoli, U [ENEA, NUC-RIN, 4 Via Martiri del Sole, 40100, Bologna (Italy)

    1994-09-01

    This paper presents the results of the activation and decay heat calculations for the divertor plate materials of the Next European Torus (NET). The basic option assessed enables molybdenum alloy TZM and AISI 316L as material for divertor cooling channels. Burn time, effective irradiation time history, and fluence dependence on activation, decay heat, and contact dose is assessed. Impact of the material impurity level on the radioactive inventory is also investigated. The ANITA code is used, with updated cross sections and decay data libraries based on EFF-2 and EAF-3 evaluation files. The flux-weighted spectrum provided by XSDRNPM or ANISN 1-D codes has been used. The real NET geometry was modelled with the 3-D MCNP Monte Carlo neutron transport code. ((orig.))

  6. Redox‐Flow Batteries: From Metals to Organic Redox‐Active Materials

    Science.gov (United States)

    Winsberg, Jan; Hagemann, Tino; Janoschka, Tobias; Hager, Martin D.

    2016-01-01

    Abstract Research on redox‐flow batteries (RFBs) is currently experiencing a significant upturn, stimulated by the growing need to store increasing quantities of sustainably generated electrical energy. RFBs are promising candidates for the creation of smart grids, particularly when combined with photovoltaics and wind farms. To achieve the goal of “green”, safe, and cost‐efficient energy storage, research has shifted from metal‐based materials to organic active materials in recent years. This Review presents an overview of various flow‐battery systems. Relevant studies concerning their history are discussed as well as their development over the last few years from the classical inorganic, to organic/inorganic, to RFBs with organic redox‐active cathode and anode materials. Available technologies are analyzed in terms of their technical, economic, and environmental aspects; the advantages and limitations of these systems are also discussed. Further technological challenges and prospective research possibilities are highlighted. PMID:28070964

  7. Reduced-activation materials for fusion reactors: An overview of the proceedings

    International Nuclear Information System (INIS)

    Klueh, R.L.; Packan, N.H.; Gelles, D.S.; Okada, M.

    1988-01-01

    Some of the most serious safety and environmental concerns for future fusion reactors involve induced radioactivity in the first wall and blanket structures. One problem caused by the induced radioactivity in a reactor constructed from the conventional austenitic and ferritic steels presently being considered as structural materials would be the disposal of the highly radioactive structures after their service lifetimes. To simplify the waste-disposal process, ''low-activation'' or ''reduced-activation'' alloys are being developed. The objective for such materials is that they qualify for shallow land burial, as opposed to the much more expensive deep geologic disposal. This paper reviews these classes of materials for this purpose: austenitic stainless steels, ferritic steels, and vanadium alloys

  8. Active Learning and Just-in-Time Teaching in a Material and Energy Balances Course

    Science.gov (United States)

    Liberatore, Matthew W.

    2013-01-01

    The delivery of a material and energy balances course is enhanced through a series of in-class and out-of-class exercises. An active learning classroom is achieved, even at class sizes over 150 students, using multiple instructors in a single classroom, problem solving in teams, problems based on YouTube videos, and just-in-time teaching. To avoid…

  9. Potential interferences inherent in neutron-activation analysis of trace elements in biological materials

    International Nuclear Information System (INIS)

    Cornells, R.; Hoste, J.; Versieck, J.

    1982-01-01

    A comprehensive review is given of how neutron-activation analysis for trace elements in biological matrices can be jeopardized by radiation damage, by the impurities present in the packing material or by nuclear interferences of major elements. Systematic errors during the counting process and the quantitative interpretation of the γ-ray spectra should not be disregarded. (author)

  10. Neutron-Activation Analysis of Biological Material with High Radiation Levels

    Energy Technology Data Exchange (ETDEWEB)

    Samsahl, K

    1966-09-15

    A method has been developed for the chemical separation and subsequent gamma-spectrometric analysis of the alkali metals, the alkaline earths, the rare earths, chromium, hafnium, lanthanum, manganese, phosphorus, scandium and silver in neutron-activated biological material. The separation steps, being fully automatic, are based on a combination of ion-exchange and partition chromatography and require 40 min.

  11. Neutron-Activation Analysis of Biological Material with High Radiation Levels

    International Nuclear Information System (INIS)

    Samsahl, K.

    1966-09-01

    A method has been developed for the chemical separation and subsequent gamma-spectrometric analysis of the alkali metals, the alkaline earths, the rare earths, chromium, hafnium, lanthanum, manganese, phosphorus, scandium and silver in neutron-activated biological material. The separation steps, being fully automatic, are based on a combination of ion-exchange and partition chromatography and require 40 min

  12. Tritium release from lithium titanate, a low-activation tritium breeding material

    International Nuclear Information System (INIS)

    Kopasz, J.P.; Miller, J.M.; Johnson, C.E.

    1994-01-01

    The goals for fusion power are to produce energy in as safe, economical, and environmentally benign a manner as possible. To ensure environmentally sound operation low-activation materials should be used where feasible. The ARIES Tokamak Reactor Study has based reactor designs on the concept of using low-activation materials throughout the fusion reactor. For the tritium breeding blanket, the choices for low activation tritium breeding materials are limited. Lithium titanate is an alternative low-activation ceramic material for use in the tritium breeding blanket. To date, very little work has been done on characterizing the tritium release for lithium titanate. We have thus performed laboratory studies of tritium release from irradiated lithium titanate. The results indicate that tritium is easily removed from lithium titanate at temperatures as low as 600 K. The method of titanate preparation was found to affect the tritium release, and the addition of 0.1% H 2 to the helium purge gas did not improve tritium recovery. ((orig.))

  13. A conceptual framework for outsourcing of materials handling activities in automotive : differentiation and implementation

    NARCIS (Netherlands)

    Klingenberg, W.; Boksma, J. D.

    2010-01-01

    This article discusses the outsourcing of materials handling activities and investigates different options for its implementation. The article uses descriptive case studies found in literature from the Western European automotive industry to map out differences in current practice and to evaluate

  14. Unidirectional high gain brake stop

    Science.gov (United States)

    Lang, David J. (Inventor)

    1987-01-01

    This invention relates to a unidirectional high gain brake arrangement that includes in combination a shaft mounted for rotation within a housing. The shaft is rotatable in either direction. A brake is selectively releasably coupled to the housing and to the shaft. The brake has a first member. An intermittent motion device is respectively coupled through the first member to the housing and through a one-way clutch to the shaft. The brake also has a second member that is mechanically coupled to the first brake member and to the housing. The intermittent motion device causes the brake to be activated by movement imparted to the first brake member after a preset number of revolutions of the shaft in one direction. The brake is released by rotation of the shaft in an opposite direction whereby torque transmitted through the one-way clutch to the first brake member is removed.

  15. Boesmanland gains from nuclear wastes

    International Nuclear Information System (INIS)

    Smit, I.

    1984-01-01

    It is being claimed that the geobotany of the Boesmanland will gain from the use of the farm Vaalputs for radioactive waste disposal from the Koeberg nuclear power station. Only 1 km 2 of the 10 000 ha that was bought for the purpose will be used for the disposal of low-level radioactive wastes and 2 m 3 to 3 m 3 per year will be used for the storage of high-level radioactive wastes. The rest of the area, Nucor plans to develop as a nature reserve, restoring the natural botany and ecology. Before Vaalputs was selected as site for radioactive waste disposal, a regional analysis was done. According to this there is more or less 500 people staying within a radius of 25km from the farm. Geological surveys showed no mineral deposits of economic value. During the past 100 million years the area was also free from seismic activity

  16. Critical outlook and trends for environmental reference materials at the Measurements & Testing Generic Activity (European Commission).

    Science.gov (United States)

    Quevauviller, P; Bennink, D; Bøwadt, S

    2001-05-01

    It is now well recognised that the quality control (QC) of all types of analyses, including environmental analyses depends on the appropriate use of reference materials. One of the ways to check the accuracy of methods is based on the use of Certified Reference Materials (CRMs), whereas other types of (not certified) Reference Materials (RMs) are used for routine quality control (establishment of control charts) and interlaboratory testing (e.g. proficiency testing). The perception of these materials, in particular with respect to their production and use, differs widely according to various perspectives (e.g. RM producers, routine laboratories, researchers). This review discusses some critical aspects of RM use and production for the QC of environmental analyses and describes the new approach followed by the Measurements & Testing Generic Activity (European Commission) to tackle new research and production needs.

  17. IAEA Activities on Application of Nuclear Techniques in Development and Characterization of Materials for Hydrogen Economy

    International Nuclear Information System (INIS)

    Salame, P.; Zeman, A.; Mulhauser, F.

    2011-01-01

    Hydrogen and fuel cells can greatly contribute to a more sustainable less carbon-dependent global energy system. An effective and safe method for storage of hydrogen in solid materials is one of the greatest technologically challenging barriers of widespread introduction of hydrogen in global energy systems. However, aspects related to the development of effective materials for hydrogen storage and fuel cells are facing considerable technological challenges. To reach these goals, research efforts using a combination of advanced modeling, synthesis methods and characterization tools are required. Nuclear methods can play an effective role in the development and characterization of materials for hydrogen storage. Therefore, the IAEA initiated a coordinated research project to promote the application of nuclear techniques for investigation and characterization of new/improved materials relevant to hydrogen and fuel cell technologies. This paper gives an overview of the IAEA activities in this subject. (author)

  18. Porous alkali activated materials with slow alkali release dynamic. Role of composition

    International Nuclear Information System (INIS)

    Bumanis, G.; Bajare, D.

    2018-01-01

    Alkali activated materials (AAM) based on calcined metakaolin or illite clay together with waste by-products, such as waste glass or aluminium scrap recycling waste, were tested as value-added materials for pH stabilization in biogas technology where decrease of pH should be avoided. Porous materials with ability to slowly leach alkalis in the water media thus providing continuous control of the pH level were obtained. XRD, FTIR, SEM and titration methods were used to characterize AAM and their leaching properties. It is clear that composition of the material has an important effect on the diffusion of alkali from structure. Namely, higher Si/Al and Na/Al molar ratios may increase pore solution transfer to the leachate. The leaching rate of alkalis from the structure of AAM is high for the first few days, decreasing over time. It was possible to calculate the buffer capacity from the mixture design of AAM. [es

  19. Source Correlated Prompt Neutron Activation Analysis for Material Identification and Localization

    Science.gov (United States)

    Canion, Bonnie; McConchie, Seth; Landsberger, Sheldon

    2017-07-01

    This paper investigates the energy spectrum of photon signatures from an associated particle imaging deuterium tritium (API-DT) neutron generator interrogating shielded uranium. The goal is to investigate if signatures within the energy spectrum could be used to indirectly characterize shielded uranium when the neutron signature is attenuated. By utilizing the correlated neutron cone associated with each pixel of the API-DT neutron generator, certain materials can be identified and located via source correlated spectrometry of prompt neutron activation gamma rays. An investigation is done to determine if fission neutrons induce a significant enough signature within the prompt neutron-induced gamma-ray energy spectrum in shielding material to be useful for indirect nuclear material characterization. The signature deriving from the induced fission neutrons interacting with the shielding material was slightly elevated in polyethylene-shielding depleted uranium (DU), but was more evident in some characteristic peaks from the aluminum shielding surrounding DU.

  20. Results of an international comparison for the determination of radionuclide activity in bilberry material

    International Nuclear Information System (INIS)

    Wätjen, U.; Altzitzoglou, T.; Ceccatelli, A.; Dikmen, H.; Emteborg, H.; Ferreux, L.; Frechou, C.; La Rosa, J.; Luca, A.; Moreno, Y.; Oropesa, P.; Pierre, S.; Schmiedel, M.

    2012-01-01

    Radioactivity found in wild food products has assumed greater importance when assessing the total exposure of the population. For this reason, IRMM has been developing a reference material for the activity concentration of three radionuclides in bilberry samples. In order to characterise this new material, a CCRI(II) supplementary comparison was organised. The difficulties encountered in this comparison are discussed, in particular the efficiency calibration for volume sources of gamma-ray emitters, and comparison reference values for 137 Cs and 40 K are calculated. - Highlights: ► CCRI(II) supplementary comparison for Cs-137 and K-40 in bilberry matrix completed. ► Fundamentally different methods used to establish link to SI traceable standards and SIR. ► Variation of results higher than in CCRI(II) key comparisons. ► Comparison reference values will be robust property values of IRMM reference material. ► Certified reference material for radioactivity in food developed.

  1. Revision of the inventory and recycling scenario of active material in near-term PPCS models

    International Nuclear Information System (INIS)

    Pampin, R.; Massaut, V.; Taylor, N.P.

    2007-01-01

    A sound approach to the recycling of fusion irradiated material is being developed. Study of industry experience, and consideration of realistic processing routes and techniques, provide a more sensible estimation of recycling feasibility than earlier studies based on purely radiological criteria. Under this approach, the analysis of active material in two models of the power plant conceptual study (PPCS) has been revised in more detail and accounting for the latest design features, nuclear data and international guidelines. A careful inventory of the materials has been performed, and estimation made of the radiological characteristics of all PPCS tokamak components, for the first time studying individual constituents and materials. Evaluation has been made of time scales for the radioactivity to decay to predetermined levels, which represent the spectrum of technological difficulties posed by the nature of the irradiated material. Three main mechanisms for the optimization of the materials management strategy have been identified during the assessments: segregation of components into individual materials, in situ refurbishment and stringent impurity control

  2. Ability to Gain Control Over One’s Own Brain Activity and its Relation to Spiritual Practice: A Multimodal Imaging Study

    Directory of Open Access Journals (Sweden)

    Silvia E. Kober

    2017-05-01

    Full Text Available Spiritual practice, such as prayer or meditation, is associated with focusing attention on internal states and self-awareness processes. As these cognitive control mechanisms presumably are also important for neurofeedback (NF, we investigated whether people who pray frequently (N = 20 show a higher ability of self-control over their own brain activity compared to a control group of individuals who rarely pray (N = 20. All participants underwent structural magnetic resonance imaging (MRI and one session of sensorimotor rhythm (SMR, 12–15 Hz based NF training. Individuals who reported a high frequency of prayer showed improved NF performance compared to individuals who reported a low frequency of prayer. The individual ability to control one’s own brain activity was related to volumetric aspects of the brain. In the low frequency of prayer group, gray matter volumes in the right insula and inferior frontal gyrus were positively associated with NF performance, supporting prior findings that more general self-control networks are involved in successful NF learning. In contrast, participants who prayed regularly showed a negative association between gray matter volume in the left medial orbitofrontal cortex (Brodmann’s area (BA 10 and NF performance. Due to their regular spiritual practice, they might have been more skillful in gating incoming information provided by the NF system and avoiding task-irrelevant thoughts.

  3. Benchmark studies of induced radioactivity produced in LHC materials, Part I: Specific activities.

    Science.gov (United States)

    Brugger, M; Khater, H; Mayer, S; Prinz, A; Roesler, S; Ulrici, L; Vincke, H

    2005-01-01

    Samples of materials which will be used in the LHC machine for shielding and construction components were irradiated in the stray radiation field of the CERN-EU high-energy reference field facility. After irradiation, the specific activities induced in the various samples were analysed with a high-precision gamma spectrometer at various cooling times, allowing identification of isotopes with a wide range of half-lives. Furthermore, the irradiation experiment was simulated in detail with the FLUKA Monte Carlo code. A comparison of measured and calculated specific activities shows good agreement, supporting the use of FLUKA for estimating the level of induced activity in the LHC.

  4. Benchmark studies of induced radioactivity produced in LHC materials, part I: Specific activities

    International Nuclear Information System (INIS)

    Brugger, M.; Khater, H.; Mayer, S.; Prinz, A.; Roesler, S.; Ulrici, L.; Vincke, H.

    2005-01-01

    Samples of materials which will be used in the LHC machine for shielding and construction components were irradiated in the stray radiation field of the CERN-EU high-energy reference field facility. After irradiation, the specific activities induced in the various samples were analysed with a high-precision gamma spectrometer at various cooling times, allowing identification of isotopes with a wide range of half-lives. Furthermore, the irradiation experiment was simulated in detail with the FLUKA Monte Carlo code. A comparison of measured and calculated specific activities shows good agreement, supporting the use of FLUKA for estimating the level of induced activity in the LHC. (authors)

  5. Building up an electrocatalytic activity scale of cathode materials for organic halide reductions

    International Nuclear Information System (INIS)

    Bellomunno, C.; Bonanomi, D.; Falciola, L.; Longhi, M.; Mussini, P.R.; Doubova, L.M.; Di Silvestro, G.

    2005-01-01

    A wide investigation on the electrochemical activity of four model organic bromides has been carried out in acetonitrile on nine cathodes of widely different affinity for halide anions (Pt, Zn, Hg, Sn, Bi, Pb, Au, Cu, Ag), and the electrocatalytic activities of the latter have been evaluated with respect to three possible inert reference cathode materials, i.e. glassy carbon, boron-doped diamond, and fluorinated boron-doped diamond. A general electrocatalytic activity scale for the process is proposed, with a discussion on its modulation by the configuration of the reacting molecule, and its connection with thermodynamic parameters accounting for halide adsorption

  6. Removal of blue indigo and cadmium present in aqueous solutions using a modified zeolitic material and an activated carbonaceous material; Remocion de azul indigo y cadmio presentes en soluciones acuosas empleando un material zeolitico modificado y un material carbonoso activado

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez S, E. E.

    2011-07-01

    In the last years the use of water has been increased substantially, it has been also altered its quality as a result of human activities such as mining, industrial activities and others. Water pollution caused by dyes and heavy metals has adverse effects on the environment, since both pollutants are very persisten even after conventional treatments. Denim blue and cadmium are not biodegradable. There is a growing interest in finding new, efficient and low cost alternative materials to remove such pollutants from the aqueous medium. The purpose of this work was to evaluate a modified zeolitic tuff and an activated carbonaceous material obtained from the pyrolysis of sewage sludge for the removal of denim blue and cadmium. The zeolitic material was modified with Na{sup +} and Fe{sup 3+} solutions to improve its sorption properties for the removal of cadmium and denim blue, respectively. Carbonaceous material was treated with 10% HCl solution to remove ashes. Both materials were characterized by scanning electron microscopy and elemental analysis (EDS), specific surface areas (Bet), thermogravimetric analysis, infrared spectroscopy and X-ray diffraction. Simultaneously, the denim blue dye was characterized by infrared spectroscopy and its pKa value was determined, these data allowed the determination of its chemical properties and its acid-base behavior in solution. In the content of this work the term indigo blue was changed by denim blue, as it corresponds to the commercial name of the dye. To assess the sorption capacity of sorbents, the sorption kinetics and sorption isotherms in batch system were determined; the results were fitted to mathematical models such as the pseudo-first order, pseudo second order and second order to describe the sorption kinetics and the Langmuir, Freundlich and Langmuir-Freundlich isotherms to describe sorption processes. The results show that the most efficient material to remove denim blue from aqueous solutions is the carbonaceous

  7. The effect of a self-constructed material on children's physical activity during recess.

    Science.gov (United States)

    Méndez-Giménez, Antonio; Cecchini, José-Antonio; Fernández-Río, Javier

    2017-06-26

    To analyze whether an intervention supported by free play with a self-constructed material increases the level of physical activity of students during recess. The participants were 166 children of third to sixth grade, between nine and 12 years old (average = 10.64; SS = 1.13). An experimental project was conducted with pre-test and post-test measurement, and a control group. Experimental group participants built cardboard paddles (third and fourth) and flying rings (fifth and sixth), a material they used freely for one week during recess. ActiGraph-GT3X accelerometers were used to measure physical activity. An ANOVA of repeated measures was used to find differences between groups and genders. Significant intervention effects were found in the analyzed variables: sedentary activity (F = 38.19; p estrategia a gestores y profesores para incrementar la actividad física de los niños durante el recreo.

  8. Preparation and Properties of Paraffin/TiO2/Active-carbon Composite Phase Change Materials

    Directory of Open Access Journals (Sweden)

    HAO Yong-gan

    2016-11-01

    Full Text Available A novel composite phase change materials (PCMs of paraffin/TiO2/active-carbon was prepared by a microemulsion method, where paraffin acted as a PCM and titanium dioxide (TiO2 as matrix material, and a small amount of active carbon was added to improve the thermal conductivity. The compositions, morphology and thermal properties of the paraffin/TiO2/active-carbon composite PCMs were characterized by XRD, SEM, TGA and DSC respectively. The shape stability during phase change process of this composite was also tested. The results show that paraffin is well encapsulated by TiO2 matrix, and thus exhibiting excellent shape-stabilized phase change feature. Besides, this composite PCM also presents superhydrophobic property. Therefore, these multifunctional features will endow PCMs with important application potential in energy efficient buildings.

  9. Rapeseed and Raspberry Seed Cakes as Inexpensive Raw Materials in the Production of Activated Carbon by Physical Activation: Effect of Activation Conditions on Textural and Phenol Adsorption Characteristics

    Directory of Open Access Journals (Sweden)

    Koen Smets

    2016-07-01

    Full Text Available The production of activated carbons (ACs from rapeseed cake and raspberry seed cake using slow pyrolysis followed by physical activation of the obtained solid residues is the topic of this study. The effect of activation temperature (850, 900 and 950 °C, activation time (30, 60, 90 and 120 min and agent (steam and CO2 on the textural characteristics of the ACs is investigated by N2 adsorption. In general, higher activation temperatures and longer activation times increase the BET specific surface area and the porosity of the ACs, regardless of the activation agent or raw material. Steam is more reactive than CO2 in terms of pore development, especially in the case of raspberry seed cake. The performance of the ACs in liquid adsorption is evaluated by batch phenol adsorption tests. Experimental data are best fitted by the Freundlich isotherm model. Based on total yield, textural characteristics and phenol adsorption, steam activation at 900 °C for 90 min and CO2 activation at 900 °C for 120 min are found as the best activation conditions. Raspberry seed cake turns out to be a better raw material than rapeseed cake. Moreover, AC from raspberry seed cake produced by steam activation at 900 °C for 90 min performs as well as commercial AC (Norit GAC 1240 in phenol adsorption. The adsorption kinetics of the selected ACs are best fitted by the pseudo-second-order model.

  10. A computational framework for the optimal design of morphing processes in locally activated smart material structures

    International Nuclear Information System (INIS)

    Wang, Shuang; Brigham, John C

    2012-01-01

    A proof-of-concept study is presented for a strategy to obtain maximally efficient and accurate morphing structures composed of active materials such as shape memory polymers (SMP) through synchronization of adaptable and localized activation and actuation. The work focuses on structures or structural components entirely composed of thermo-responsive SMP, and particularly utilizes the ability of such materials to display controllable variable stiffness. The study presents and employs a computational inverse mechanics approach that combines a computational representation of the SMP thermo-mechanical behavior with a nonlinear optimization algorithm to determine location, magnitude and sequencing of the activation and actuation to obtain a desired shape change subject to design objectives such as prevention of damage. Two numerical examples are presented in which the synchronization of the activation and actuation and the location of activation excitation were optimized with respect to the combined thermal and mechanical energy for design concepts in morphing skeletal structural components. In all cases the concept of localized activation along with the optimal design strategy were able to produce far more energy efficient morphing structures and more accurately reach the desired shape change in comparison to traditional methods that require complete structural activation prior to actuation. (paper)

  11. Reduced activation structural materials for fusion power plants - The European Union program

    International Nuclear Information System (INIS)

    Schaaf, B. van der; Le Marois, G.; Moeslang, A.; Victoria, M.

    2003-01-01

    The competition of fusion power plants with the renewable energy sources in the second half of the 21st century requires structural materials operating at high temperatures, and sufficient radiation resistance to ensure high plant efficiency and availability. The reduced activation materials development in the EU counts several steps regarding the radiation damage resistance: 75 dpa for DEMO and 150 dpa and beyond for power plants. The maximum operating temperature development line ranges from the present day from the present day feasible 600 K up to 1300- K in advanced power plants. The reduced activation steel, RAS, forms the reference for the development efforts. EUROFER has been manufactured in the EU on industrial scale with specified purity and mechanical properties up to 825 K. The oxide dispersion strengthened , ODS, variety of RAS should reach the 925 K operation limit. The EU has selected silicon carbide ceramic composite as the primary high temperature, 1300 K, goal. On a small scale the potential of tungsten alloys for higher temperatures is investigated. The present test environments for radiation resistance are insufficient to provide data for DEMO. Hence the support of the EU for the International Fusion Materials Irradiation facility. The computational modelling is expected to guide the materials development and the design of near plasma components. The EU co-operates closely with Japan, the RF and US in IEA and IAEA co-ordinated agreements, which are highly beneficial for the fusion structural materials development. (author)

  12. A 3-year physical activity intervention program increases the gain in bone mineral and bone width in prepubertal girls but not boys: the prospective copenhagen school child interventions study (CoSCIS).

    Science.gov (United States)

    Hasselstrøm, H A; Karlsson, M K; Hansen, S E; Grønfeldt, V; Froberg, K; Andersen, L B

    2008-10-01

    The aim of this study was to evaluate the effect of increasing the amount of time spent in physical education classes on bone mineral accrual and gain in bone size in prepubertal Danish children. A total of 135 boys and 108 girls, aged 6-8 years, were included in a school-based curriculum intervention program where the usual time spent in physical education classes was doubled to four classes (180 min) per week. The control group comprised age-matched children (62 boys and 76 girls) recruited from a separate community who completed the usual Danish school curriculum of physical activity (90 min/week). Dual-energy X-ray absorptiometry was used to evaluate bone mineral content (BMC; g), bone mineral density (g/cm(2)), and bone width at the calcaneus and distal forearm before and after 3 years of intervention. Anthropometrics and Tanner stages were evaluated on the same occasions. General physical activity was measured with an accelerometer worn for 4 days. In girls, the intervention group had a 12.5% increase (P = 0.04) in distal forearm BMC and a 13.2% increase (P = 0.005) in distal forearm scanned area compared with girls in the control group. No differences were found between the intervention and control groups in boys. Increasing the frequency of physical education classes for prepubertal children is associated with a higher accrual of bone mineral and higher gain in bone size after 3 years in girls but not in boys.

  13. Secondary cell with orthorhombic alkali metal/manganese oxide phase active cathode material

    Science.gov (United States)

    Doeff, Marca M.; Peng, Marcus Y.; Ma, Yanping; Visco, Steven J.; DeJonghe, Lutgard C.

    1996-01-01

    An alkali metal manganese oxide secondary cell is disclosed which can provide a high rate of discharge, good cycling capabilities, good stability of the cathode material, high specific energy (energy per unit of weight) and high energy density (energy per unit volume). The active material in the anode is an alkali metal and the active material in the cathode comprises an orthorhombic alkali metal manganese oxide which undergoes intercalation and deintercalation without a change in phase, resulting in a substantially linear change in voltage with change in the state of charge of the cell. The active material in the cathode is an orthorhombic structure having the formula M.sub.x Z.sub.y Mn.sub.(1-y) O.sub.2, where M is an alkali metal; Z is a metal capable of substituting for manganese in the orthorhombic structure such as iron, cobalt or titanium; x ranges from about 0.2 in the fully charged state to about 0.75 in the fully discharged state, and y ranges from 0 to 60 atomic %. Preferably, the cell is constructed with a solid electrolyte, but a liquid or gelatinous electrolyte may also be used in the cell.

  14. Active materials for adaptive architectural envelopes based on plant adaptation principles

    Directory of Open Access Journals (Sweden)

    Marlen Lopez

    2015-06-01

    Full Text Available In this paper, the authors present research into adaptive architectural envelopes that adapt to environmental changes using active materials, as a result of application of biomimetic principles from plants to architecture. Buildings use large amounts of energy in order to maintain their internal comfort, because conventional buildings are designed to provide a static design solution. Most of the current solutions for facades are not designed for optimum adaptation to contextual issues and needs, while biological solutions to adaptation are often complex, multi-functional and highly responsive. We focus on plant adaptations to the environment, as, due to their immobility, they have developed special means of protection against weather changing conditions. Furthermore, recent developments in new technologies are allowing the possibility to transfer these plant adaptation strategies to technical implementation. These technologies include: multi-material 3D printing, advances in materials science and new capabilities in simulation software. Unlike traditional mechanical activation used for dynamic systems in kinetic facades, adaptive architectural envelopes require no complex electronics, sensors, or actuators. The paper proposes a research of the relationship that can be developed between active materials and environmental issues in order to propose innovative and low-tech design strategies to achieve living envelopes according to plant adaptation principles.  

  15. Certification of biological reference materials: participation of the Neutron Activation Laboratory (LAN-IPEN/CNEN-SP)

    International Nuclear Information System (INIS)

    Ticianelli, Regina B.; Figueiredo, Ana Maria G.

    2007-01-01

    Analytical laboratories have as one of their important goals to demonstrate their competence allowing international acceptance and comparison of analytical data. The IPEN Neutron Activation Laboratory (LAN-IPEN) has implemented its Quality Assurance Program which comprises, among other activities, the participation in intercomparison runs. As a part of this Quality Assurance Program, LAN-IPEN has participated in interlaboratorial trials to analyze two biological candidate reference materials: INCT-CF-3 Corn Flour and INCT-SBF-4 Soya Bean Flour from the Institute of Nuclear Chemistry And Technology (Warszawa, Poland). The elements Br, Ca, Co, Cs, Fe, K, Na, Rb and Zn were analyzed in the candidate reference materials by instrumental neutron activation analysis (INAA). The performance of the laboratory was statistically evaluated in relation to the consensus values for these materials using the Z-Score test. This laboratory evaluation method has been accepted as a standard by ISO/IUPAC. In the present study, adequate Z-Score values (|Z|<2) were observed for all of the analyzed elements, confirming the accuracy of the nuclear methodology employed. The contribution of LAN-IPEN in the certification of the reference materials analyzed was very important, since the results provided were used in the statistical evaluation of the certified value. (author)

  16. Relative contributions of energy expenditure on physical activity, body composition and weight gain to the evolution of impaired glucose to tolerance to Frank diabetes

    International Nuclear Information System (INIS)

    Forrester, T.; Wilks, R.; Gaskin, P.; Luke, A.; Jahoor, F.; Adeyemo, A.

    2002-01-01

    There is a gradient of diabetes prevalence among populations of the African Diaspora, with a rate of about 1% in West Africa, 12% in Jamaica and 16% in the United States. A population-based survey was conducted in an urban community in Jamaica to document the risk factors for the evolution of impaired glucose tolerance to frank diabetes. In a sample of 614 adults, 239 men and 375 women, oral glucose tolerance tests and examinations were conducted at Baseline and after 4-years of Follow-Up. There were significant increases in virtually all weight and adiposity variables for both men and women. Energy expenditure was also measured in a subset of participants at Follow-Up and was related significantly to glucose tolerance status. Among men, baseline age, weight, fat mass, body fat, waist circumference, and change in waist circumference were predictive of worsening glucose tolerance status. Among women, only age and change in waist circumference was a significant predictor. No physical activity parameter was predictive of change in tolerance status. These results provide support for the need to decrease adiposity as an important mechanism to control the rise in diabetes prevalence. (author)

  17. Antimicrobial activity and properties of irreversible hydrocolloid impression materials incorporated with silver nanoparticles.

    Science.gov (United States)

    Ginjupalli, Kishore; Alla, Rama Krishna; Tellapragada, Chaitanya; Gupta, Lokendra; Upadhya Perampalli, Nagaraja

    2016-06-01

    Conventional spray and the immersion disinfection of irreversible hydrocolloid impression materials may lead to dimensional changes. The purpose of this in vitro study was to investigate the antimicrobial activity and properties of irreversible hydrocolloid impression materials incorporated with silver nanoparticles. The antimicrobial activity and properties of 2 commercially available irreversible hydrocolloid impression materials were evaluated after incorporating varying concentrations of silver nanoparticles. Antimicrobial activity was determined using the disk diffusion method. The gel strength, permanent deformation, flow, and gelation time were measured according to American Dental Association specification #18. Analysis of variance was used to identify the significant differences within and across the groups (α=.05). Adding silver nanoparticles to irreversible hydrocolloid impression materials resulted in superior antimicrobial activity without adversely affecting their properties. Adding silver nanoparticles to Zelgan significantly increased the gel strength compared with the control group, except at 5 wt%. However, the gel strength of Tropicalgin was unaffected except at 5 wt%. An increase in the permanent deformation was found with the incorporation of silver nanoparticles in both Zelgan and Tropicalgin. The flow of Zelgan increased with the incorporation of silver nanoparticles, whereas a decrease in the flow of Tropicalgin was observed at 1 wt% and 2 wt%. An increase in the gelation time of both Zelgan and Tropicalgin was observed with the incorporation of silver nanoparticles. Based on this in vitro study, silver nanoparticles can be incorporated into irreversible hydrocolloid impression materials as antimicrobial agents without adversely affecting their properties. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  18. Activation time and material stiffness of sequential removable orthodontic appliances. Part 2: Dental improvements.

    Science.gov (United States)

    Clements, Karen Michelle; Bollen, Anne-Marie; Huang, Greg; King, Greg; Hujoel, Philippe; Ma, Tsun

    2003-11-01

    Fifty-one patients were enrolled in this study to explore the treatment effects of material stiffness and frequency of appliance change when using clear, sequential, removable appliances (aligners). Patients were stratified based on pretreatment peer assessment rating (PAR) scores and need for extractions. They were randomized into 4 treatment protocols: 1-week activation with soft material, 1-week activation with hard material, 2-week activation with soft material, and 2-week activation with hard material. Patients continued with their protocols until either the series of aligners was completed, or until it was determined that the aligner was not fitting well (study end point). Weighted PAR score and average incisor irregularity (AII) indexes were used to measure pretreatment and end-point study models, and average improvement was compared among the 4 groups. In addition to the evaluation of the 4 treatment groups, comparisons were made of the individual components of the PAR score to determine which occlusal components experienced the most correction with the aligners. The percentages and absolute extraction space closures were evaluated, and papillary bleeding scores before and during treatment were compared. Although no statistical difference was observed between the 4 treatment groups, a trend was noted with the 2-week frequency having a larger percentage of reduction in weighted PAR and AII scores, and greater extraction space closure. Anterior alignment was the most improved component, and buccal occlusion was the least improved. When analyzed by type of extraction, incisor extraction sites had a significantly greater percentage of closure than either maxillary or mandibular premolar extraction sites. A statistically significant decrease in mean average papillary bleeding score was found during treatment when compared with pretreatment scores, although this difference was not clinically significant.

  19. High Efficient Enrichment and Activated Dissolution of Refractory Low Grade Rh-containing Material

    Institute of Scientific and Technical Information of China (English)

    WU Xiaofeng; DONG Haigang; TONG Weifeng; ZHAO Jiachun; ZENG Rui

    2012-01-01

    Aiming to the low-grade rhodium-containing waste materials,a new process was proposed to enrich and activate rhodium by smelting using iron oxide as a trapping agent and activator.A rhodium concentrate was obtained by the separation of base metals and precious metals.The concentrate was reacted with dilute aqua regia to obtain rhodium solution.The factors influencing the enrichment and activation effects were discussed in this paper.The results showed that the dissolution rate is greater than 99% under the optimum conditions.In this process,the activation of rhodium was finished in the enrichment process.The iron oxide is both a trapping agent and activator,which simplifies the process and reduce the cost.

  20. Determination of mercury concentration in biological materials by neutron activation analysis

    International Nuclear Information System (INIS)

    Munoz, L.; Gras, N.; Cortes, E.; Cassorla, V.

    1983-01-01

    The objective of this work was to obtain a confident analytical method for measuring the mercury concentration in biological materials. Destructive neutron activation analysis was used for this purpose and a radiochemical separation method was studied to isolate the mercury from its main interferences: sodium and phosphorus, because these elements in biological materials are in high concentrations. The method developed was based on the copper amalgamation under controlled conditions. Yield and reproductibility studies were performed using 203 Hg as radioactive tracer. Finally, food samples of regular consumption were analyzed and the results were compared with those recommended by FAO/WHO. (Author)

  1. A trap activation model for hydrogen retention and isotope exchange in some refractory materials

    International Nuclear Information System (INIS)

    Brice, D.K.; Doyle, B.L.

    1982-01-01

    Our recently-developed Local Mixing Model (LMM) has been successful in describing and predicting the properties of hydrogen retention and isotope exchange for a variety of refractory materials. For some materials, however, the detailed predictions of the LMM are not observed. A Trap Activation Model (TAM) is proposed here to account for the observed departures from the LMM. Comparison of experimental room temperature saturation depth profiles for H + →Si with the predictions of TAM suggests that the hydrogen traps are multiple-vacancy complexes in this system. The observed profiles result from a beam-induced competition between trap creation/annihilation and H-trapping/detrapping. (orig.)

  2. Instrumental neutron activation analysis for the certification of biological reference materials

    International Nuclear Information System (INIS)

    Ambulkar, M.N.; Chutke, N.L.; Garg, A.N.

    1992-01-01

    A multielemental instrumental neutron activation analysis (INAA) method by short and long irradiation has been employed for the determination of 22 minor and trace constituents in two proposed Standard Reference Materials P-RBF and P-WBF from Institute of Radioecology and Applied Nuclear Techniques, Czechoslovakia. Also some biological standards such as Bowen's Kale, Cabbage leaves (Poland) including wheat and rice flour samples of local origin were analysed. It is suggested that INAA is an ideal method for the certification of reference materials of biological matrices. (author). 7 refs., 1 tab

  3. Research about the pozzolanic activity of waste materials from calcined clay

    Directory of Open Access Journals (Sweden)

    Sánchez de Rojas, M. I.

    2001-03-01

    Full Text Available To recycle and reutilise waste materials and find definite applications for their use, it is necessary to have a deep knowledge of them. The aim of this study is to study the possibility of using waste materials from calcined clay, actually ceramic tile, once crushed and grounded, as pozzolanic material. For this purpose, different tests are carried out in order to establish the pozzolanic activity of this material. At the same time, these results are compared to those of other industrial by-products, fly ash and silica fume, which are pozzolanic materials usually employed to elaborate mortars and concretes.

    Para llevar a cabo labores encaminadas al reciclado y revalorización de residuos es necesario un conocimiento profundo de los mismos, de forma que se busquen aplicaciones concretas de uso. El objetivo de este estudio es investigar la posibilidad de utilizar materiales de desecho procedentes de arcilla cocida, concretamente teja cerámica, una vez triturada y molida, como puzolana. Para ello, se efectúan diferentes ensayos dirigidos a establecer la actividad puzolanica del material. A su vez, estos resultados son comparados con otros residuos industriales, ceniza volante y humo de sílice, habituales en la elaboración de morteros y hormigones.

  4. Purely Organic Thermally Activated Delayed Fluorescence Materials for Organic Light-Emitting Diodes.

    Science.gov (United States)

    Wong, Michael Y; Zysman-Colman, Eli

    2017-06-01

    The design of thermally activated delayed fluorescence (TADF) materials both as emitters and as hosts is an exploding area of research. The replacement of phosphorescent metal complexes with inexpensive organic compounds in electroluminescent (EL) devices that demonstrate comparable performance metrics is paradigm shifting, as these new materials offer the possibility of developing low-cost lighting and displays. Here, a comprehensive review of TADF materials is presented, with a focus on linking their optoelectronic behavior with the performance of the organic light-emitting diode (OLED) and related EL devices. TADF emitters are cross-compared within specific color ranges, with a focus on blue, green-yellow, orange-red, and white OLEDs. Organic small-molecule, dendrimer, polymer, and exciplex emitters are all discussed within this review, as is their use as host materials. Correlations are provided between the structure of the TADF materials and their optoelectronic properties. The success of TADF materials has ushered in the next generation of OLEDs. © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Evaluation of Activity Concentration Values and Doses due to the Transport of Low Level Radioactive Material

    Energy Technology Data Exchange (ETDEWEB)

    Rawl, Richard R [ORNL; Scofield, Patricia A [ORNL; Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL

    2010-04-01

    The International Atomic Energy Agency (IAEA) initiated an international Coordinated Research Project (CRP) to evaluate the safety of transport of naturally occurring radioactive material (NORM). This report presents the United States contribution to that IAEA research program. The focus of this report is on the analysis of the potential doses resulting from the transport of low level radioactive material. Specific areas of research included: (1) an examination of the technical approach used in the derivation of exempt activity concentration values and a comparison of the doses associated with the transport of materials included or not included in the provisions of Paragraph 107(e) of the IAEA Safety Standards, Regulations for the Safe Transport of Radioactive Material, Safety Requirements No. TS-R-1; (2) determination of the doses resulting from different treatment of progeny for exempt values versus the A{sub 1}/A{sub 2} values; and (3) evaluation of the dose justifications for the provisions applicable to exempt materials and low specific activity materials (LSA-I). It was found that the 'previous or intended use' (PIU) provision in Paragraph 107(e) is not risk informed since doses to the most highly exposed persons (e.g., truck drivers) are comparable regardless of intended use of the transported material. The PIU clause can also have important economic implications for co-mined ores and products that are not intended for the fuel cycle but that have uranium extracted as part of their industrial processing. In examination of the footnotes in Table 2 of TS-R-1, which identifies the progeny included in the exempt or A1/A2 values, there is no explanation of how the progeny were selected. It is recommended that the progeny for both the exemption and A{sub 1}/A{sub 2} values should be similar regardless of application, and that the same physical information should be used in deriving the limits. Based on the evaluation of doses due to the transport of low

  6. Saving and gaining energy

    International Nuclear Information System (INIS)

    Lauritzen, T.

    2008-01-01

    In this interview with Dirk U. Hindrichs from the Schueco International KG company, differences between ecological and economical points of view in general are discussed, as is the world's energy consumption and the visions held by the Schueco company in this respect. The importance of building facades, windows and photovoltaics for his business is discussed, as are solar thermal systems for the production of heat and cold. Further, energy-efficiency and examples of buildings realised internationally are discussed and co-operation with important players in the climate protection area is noted. Hindrichs' opinion, that pro-active actions must be taken by entrepreneurs, is noted.

  7. Use of polyamfolit complexes of ethyl-amino-crotonate/acrylic acid with surface-active materials for radionuclide extraction

    International Nuclear Information System (INIS)

    Kabdyrakova, A.M.; Artem'ev, O.I.; Protskij, A.V.; Bimendina, L.A.; Yashkarova, M.G.; Orazzhanova, L.K.

    2005-01-01

    Pentifylline of betaine structure was synthesised on the basis of 3-aminocrotonate and acrylic acid. Polyamfolit composition and its complexes with anionic surface-active material (lauryl sulfate of sodium) were determined. It is revealed that complex formation occurs with [polyamfolit]:[surface active material]=1:1 ratio and is accompanied by significant reduce of system characteristics viscosity. The paper presents results of [polyamfolit]:[surface active material] complex apply experimental investigation for radionuclide directed migration in soil. (author)

  8. Recent Developments in C-H Activation for Materials Science in the Center for Selective C-H Activation.

    Science.gov (United States)

    Zhang, Junxiang; Kang, Lauren J; Parker, Timothy C; Blakey, Simon B; Luscombe, Christine K; Marder, Seth R

    2018-04-16

    Abstract : Organic electronics is a rapidly growing field driven in large part by the synthesis of ∏-conjugated molecules and polymers. Traditional aryl cross-coupling reactions such as the Stille and Suzuki have been used extensively in the synthesis of ∏-conjugated molecules and polymers, but the synthesis of intermediates necessary for traditional cross-couplings can include multiple steps with toxic and hazardous reagents. Direct arylation through C-H bond activation has the potential to reduce the number of steps and hazards while being more atom-economical. Within the Center for Selective C-H Functionalization (CCHF), we have been developing C-H activation methodology for the synthesis of ∏-conjugated materials of interest, including direct arylation of difficult-to-functionalize electron acceptor intermediates and living polymerization of ∏-conjugated polymers through C-H activation.

  9. Effect of different mulch materials on the soil dehydrogenase activity (DHA) in an organic pepper crop

    Science.gov (United States)

    Moreno, Marta M.; Peco, Jesús; Campos, Juan; Villena, Jaime; González, Sara; Moreno, Carmen

    2016-04-01

    The use biodegradable materials (biopolymers of different composition and papers) as an alternative to conventional mulches has increased considerably during the last years mainly for environmental reason. In order to assess the effect of these materials on the soil microbial activity during the season of a pepper crop organically grown in Central Spain, the soil dehydrogenase activity (DHA) was measured in laboratory. The mulch materials tested were: 1) black polyethylene (PE, 15 μm); black biopolymers (15 μm): 2) Mater-Bi® (corn starch based), 3) Sphere 4® (potato starch based), 4) Sphere 6® (potato starch based), 5) Bioflex® (polylactic acid based), 6) Ecovio® (polylactic acid based), 7) Mimgreen® (black paper, 85 g/m2). A randomized complete block design with four replications was adopted. The crop was drip irrigated following the water demand of each treatment. Soil samples (5-10 cm depth) under the different mulches were taken at different dates (at the beginning of the crop cycle and at different dates throughout the crop season). Additionally, samples of bare soil in a manual weeding and in an untreated control were taken. The results obtained show the negative effect of black PE on the DHA activity, mainly as result of the higher temperature reached under the mulch and the reduction in the gas interchange between the soil and the atmosphere. The values corresponding to the biodegradable materials were variable, although highlighting the low DHA activity observed under Bioflex®. In general, the uncovered treatments showed higher values than those reached under mulches, especially in the untreated control. Keywords: mulch, biodegradable, biopolymer, paper, dehydrogenase activity (DHA). Acknowledgements: the research was funded by Project RTA2011-00104-C04-03 from the INIA (Spanish Ministry of Economy and Competitiveness).

  10. Potential gains from hospital mergers in Denmark.

    Science.gov (United States)

    Kristensen, Troels; Bogetoft, Peter; Pedersen, Kjeld Moeller

    2010-12-01

    The Danish hospital sector faces a major rebuilding program to centralize activity in fewer and larger hospitals. We aim to conduct an efficiency analysis of hospitals and to estimate the potential cost savings from the planned hospital mergers. We use Data Envelopment Analysis (DEA) to estimate a cost frontier. Based on this analysis, we calculate an efficiency score for each hospital and estimate the potential gains from the proposed mergers by comparing individual efficiencies with the efficiency of the combined hospitals. Furthermore, we apply a decomposition algorithm to split merger gains into technical efficiency, size (scale) and harmony (mix) gains. The motivation for this decomposition is that some of the apparent merger gains may actually be available with less than a full-scale merger, e.g., by sharing best practices and reallocating certain resources and tasks. Our results suggest that many hospitals are technically inefficient, and the expected "best practice" hospitals are quite efficient. Also, some mergers do not seem to lower costs. This finding indicates that some merged hospitals become too large and therefore experience diseconomies of scale. Other mergers lead to considerable cost reductions; we find potential gains resulting from learning better practices and the exploitation of economies of scope. To ensure robustness, we conduct a sensitivity analysis using two alternative returns-to-scale assumptions and two alternative estimation approaches. We consistently find potential gains from improving the technical efficiency and the exploitation of economies of scope from mergers.

  11. Chitosan coatings onto polyethylene terephthalate for the development of potential active packaging material

    International Nuclear Information System (INIS)

    Zemljič, Lidija Fras; Tkavc, Tina; Vesel, Alenka; Šauperl, Olivera

    2013-01-01

    Highlights: ► The adsorption/desorption of chitosan onto PET plastic film was studied. ► Chitosan was reversible attached onto PET plastic films. ► Antimicrobial functionalized PET may provide potential active packaging material. - Abstract: In this paper advanced surface treatment of PET plastic film is presented for introduction of antimicrobial properties as a potential application for food (as for example meat) packaging material. Adsorption/desorption of chitosan onto PET plastic film surface was studied using several analytical techniques such as: X-Ray Photoelectron Spectroscopy (XPS), ATR-FTIR spectroscopy and titrations. Kinetic desorption of chitosan from PET surface was analysed by polyelectrolyte titration and spectrophotometric Ninhydrine reaction. Standard antimicrobial test ASTM E2149-01 was performed for functionalised PET materials in order to determine their antimicrobial properties; i. e. to measure the reductions of some of the meat pathogens; such as bacteria Salmonella enterica, Campylobacter spp., Escherichia coli, Listeria monocytogenes and fungi Candida albicans.

  12. Novel Flexible Wearable Sensor Materials and Signal Processing for Vital Sign and Human Activity Monitoring.

    Science.gov (United States)

    Servati, Amir; Zou, Liang; Wang, Z Jane; Ko, Frank; Servati, Peyman

    2017-07-13

    Advances in flexible electronic materials and smart textile, along with broad availability of smart phones, cloud and wireless systems have empowered the wearable technologies for significant impact on future of digital and personalized healthcare as well as consumer electronics. However, challenges related to lack of accuracy, reliability, high power consumption, rigid or bulky form factor and difficulty in interpretation of data have limited their wide-scale application in these potential areas. As an important solution to these challenges, we present latest advances in novel flexible electronic materials and sensors that enable comfortable and conformable body interaction and potential for invisible integration within daily apparel. Advances in novel flexible materials and sensors are described for wearable monitoring of human vital signs including, body temperature, respiratory rate and heart rate, muscle movements and activity. We then present advances in signal processing focusing on motion and noise artifact removal, data mining and aspects of sensor fusion relevant to future clinical applications of wearable technology.

  13. Operational gain : measuring the capture of genetic gain ...

    African Journals Online (AJOL)

    The concept of operational gain is more than the weighted average of the genetic quality of planted hectares, and encompasses tree breeding efficiencies, propagation efficiencies, matching of species and genotype to site, plant use efficiency and early measures of stand density and growth. To test the operational gain ...

  14. The monostandard method in thermal neutron activation analysis of geological, biological and environmental materials

    International Nuclear Information System (INIS)

    Alian, A.; Djingova, R.G.; Kroener, B.; Sansoni, B.

    1984-01-01

    A simple method is described for instrumental multielement thermal neutron activation analysis using a monostandard. For geological and air dust samples, iron is used as a comparator, while sodium has advantages for biological materials. To test the capabilities of this method, the values of the effective cross sections of the 23 elements determined were evaluated in a reactor site with an almost pure thermal neutron flux of about 9x10 12 nxcm -2 xs -1 and an epithermal neutron contribution of less than 0.03%. The values obtained were found to agree mostly well with the best literature values of thermal neutron cross sections. The results of an analysis by activation in the same site agree well with the relative method using multielement standards and for several standard reference materials with certified element contents. A comparison of the element contents obtained by the monostandard and relative methods together with corresponding precisions and accuracies is given. (orig.) [de

  15. Electrospun curcumin-loaded cellulose acetate/polyvinylpyrrolidone fibrous materials with complex architecture and antibacterial activity

    International Nuclear Information System (INIS)

    Tsekova, Petya B.; Spasova, Mariya G.; Manolova, Nevena E.; Markova, Nadya D.; Rashkov, Iliya B.

    2017-01-01

    Novel fibrous materials from cellulose acetate (CA) and polyvinylpyrrolidone (PVP) containing curcumin (Curc) with original design were prepared by one-pot electrospinning or dual spinneret electrospinning. The electrospun materials were characterized by scanning electron microscopy (SEM), fluorescence microscopy, Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV–Vis), differential scanning calorimetry (DSC), water contact angle measurements, and microbiological tests. It was found that the incorporation of Curc into the CA and PVP solutions resulted in an increase of the solution viscosity and obtaining fibers with larger diameters (ca. 1.5 μm) compared to the neat CA (ca. 800 nm) and PVP fibers (ca. 500 nm). The incorporation of PVP resulted in increased hydrophilicity of the fibers and in faster Curc release. Curc was found in the amorphous state in the Curc-containing fibers and these mats exhibited antibacterial activity against Staphylococcus aureus (S. aureus). The results suggest that, due to their complex architecture, the obtained new antibacterial materials are suitable for wound dressing applications, which necessitate diverse release behaviors of the bioactive compound. - Highlights: • Novel curcumin-loaded materials based on cellulose acetate and polyvinylpyrrolidone were prepared by electrospinning. • Using one-pot or dual spinneret electrospinning enabled modulating drug release. • The incorporation of polyvinylpyrrolidone resulted in faster curcumin release. • The curcumin-containing mats exhibited antibacterial activity thus rendering them suitable for wound dressing applications.

  16. Electrospun curcumin-loaded cellulose acetate/polyvinylpyrrolidone fibrous materials with complex architecture and antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Tsekova, Petya B.; Spasova, Mariya G.; Manolova, Nevena E. [Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, Acad. G. Bonchev St, bl. 103A, BG-1113 Sofia (Bulgaria); Markova, Nadya D. [Institute of Microbiology, Bulgarian Academy of Sciences, Acad. G. Bonchev St, bl. 26, BG-1113 Sofia (Bulgaria); Rashkov, Iliya B., E-mail: rashkov@polymer.bas.bg [Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, Acad. G. Bonchev St, bl. 103A, BG-1113 Sofia (Bulgaria)

    2017-04-01

    Novel fibrous materials from cellulose acetate (CA) and polyvinylpyrrolidone (PVP) containing curcumin (Curc) with original design were prepared by one-pot electrospinning or dual spinneret electrospinning. The electrospun materials were characterized by scanning electron microscopy (SEM), fluorescence microscopy, Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV–Vis), differential scanning calorimetry (DSC), water contact angle measurements, and microbiological tests. It was found that the incorporation of Curc into the CA and PVP solutions resulted in an increase of the solution viscosity and obtaining fibers with larger diameters (ca. 1.5 μm) compared to the neat CA (ca. 800 nm) and PVP fibers (ca. 500 nm). The incorporation of PVP resulted in increased hydrophilicity of the fibers and in faster Curc release. Curc was found in the amorphous state in the Curc-containing fibers and these mats exhibited antibacterial activity against Staphylococcus aureus (S. aureus). The results suggest that, due to their complex architecture, the obtained new antibacterial materials are suitable for wound dressing applications, which necessitate diverse release behaviors of the bioactive compound. - Highlights: • Novel curcumin-loaded materials based on cellulose acetate and polyvinylpyrrolidone were prepared by electrospinning. • Using one-pot or dual spinneret electrospinning enabled modulating drug release. • The incorporation of polyvinylpyrrolidone resulted in faster curcumin release. • The curcumin-containing mats exhibited antibacterial activity thus rendering them suitable for wound dressing applications.

  17. Guidance and methods for satisfying low specific activity material and surface contaminated object regulatory requirements

    International Nuclear Information System (INIS)

    Pope, R.B.; Shappert, L.B.; Michelhaugh, R.D.; Boyle, R.W.; Easton, E.P.; Coodk, J.R.

    1998-01-01

    The U.S. Department of Transportation (DOT) and the U.S. Nuclear Regulatory Commission (NRC) have prepared a comprehensive set of draft guidance for shippers and inspectors to use when applying the newly imposed regulatory requirements for low specific activity (LSA) material and surface contaminated objects (SCOs). These requirements represent significant departures in some areas from the manner in which these materials and objects were regulated by the earlier versions of the regulations. The proper interpretation and application of the regulatory criteria can require a fairly complex set of decisions be made. To assist those trying these regulatory requirements, a detailed set of logic-flow diagrams representing decisions related to multiple factors were prepared and included in the draft report for comment on Categorizing and Transporting Low Specific Activity Materials and Surface Contaminated Objects, (DOT/NRC, 1997). These logic-flow diagrams, as developed, are specific to the U.S. regulations, but were readily adaptable to the IAEA regulations. The diagrams have been modified accordingly and tied directly to specific paragraphs in IAEA Safety Series No. 6. This paper provides the logic-flow diagrams adapted in the IAEA regulations, and demonstrated how these diagrams can be used to assist consignors and inspectors in assessing compliance of shipments with the LSA material and SCO regulatory requirements. (authors)

  18. International Fusion Materials Irradiation Facility conceptual design activity. Present status and perspective

    International Nuclear Information System (INIS)

    Kondo, Tatsuo; Noda, Kenji; Oyama, Yukio

    1998-01-01

    For developing the materials for nuclear fusion reactors, it is indispensable to study on the neutron irradiation behavior under fusion reactor conditions, but there is not any high energy neutron irradiation facility that can simulate fusion reactor conditions at present. Therefore, the investigation of the IFMIF was begun jointly by Japan, USA, Europe and Russia following the initiative of IEA. The conceptual design activities were completed in 1997. As to the background and the course, the present status of the research on heavy irradiation and the testing means for fusion materials, the requirement and the technical basis of high energy neutron irradiation, and the international joint design activities are reported. The materials for fusion reactors are exposed to the neutron irradiation with the energy spectra up to 14 MeV. The requirements from the users that the IFMIF should satisfy, the demand of the tests for the materials of prototype and demonstration fusion reactors and the evaluation of the neutron field characteristics of the IFMIF are discussed. As to the conceptual design of the IFMIF, the whole constitution, the operational mode, accelerator system and target system are described. (K.I.)

  19. Estimated long lived isotope activities in ET-RR-1 reactor structural materials for decommissioning study

    International Nuclear Information System (INIS)

    Ashoub, N.; Saleh, H.

    1995-01-01

    The first Egyptian research reactor, ET-RR-1 is tank type with light water as a moderator, coolant and reflector. Its nominal power is 2MWt and the average thermal neutron flux is 10 13 n/cm 2 sec -1 . Its criticality was on the fall of 1961. The reactor went through several modifications and updating and is still utilized for experimental research. A plan for decommissioning of ET-RR-1 reactor should include estimation of radioactivity in structural materials. The inventory will help in assessing the radiological consequences of decommissioning. This paper presents a conservative calculation to estimate the activity of the long lived isotopes which can be produced by neutron activation. The materials which are presented in significant quantities in the reactor structural materials are aluminum, cast iron, graphite, ordinary and iron shot concrete. The radioactivity of each component is dependent not only upon the major elements, but also on the concentration of the trace elements. The main radioactive inventory are expected to be from 60 Co and 55 Fe which are presented in aluminium as trace elements and in large quantities in other construction materials. (author)

  20. Assessment of alpha activity of building materials commonly used in West Bengal, India

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Dipak [School of Studies in Environmental Radiation and Archaeological Sciences, Jadavpur University, Kolkata 700 032 (India); Nuclear and Particle Physics Research Centre, Department of Physics, Jadavpur University, Kolkata 700 032 (India)], E-mail: dipakghosh_in@yahoo.com; Deb, Argha; Bera, Sukumar; Sengupta, Rosalima; Patra, Kanchan Kumar [School of Studies in Environmental Radiation and Archaeological Sciences, Jadavpur University, Kolkata 700 032 (India); Nuclear and Particle Physics Research Centre, Department of Physics, Jadavpur University, Kolkata 700 032 (India)

    2008-02-15

    This paper, reports for the first time, an extensive study of alpha activity of all widely used building materials (plaster of Paris, stone chips, marble, white cement, mosaic stone, limestone, sand, granite, cement brick, asbestos, red brick, cement tile, ceramic tile and ceramics) in West Bengal, India. The alpha activities have been measured using Solid State Nuclear Track Detector (SSNTD), a very sensitive detector for alpha particles. The samples were collected from local markets of Kolkata. The measured average alpha activities ranged from 22.7 {+-} 2.5 to 590.6 {+-} 16.8 Bq kg{sup -1}. The alpha activity of ceramic tiles was highest and provides additional data to estimate the effect of environmental radiation exposure on human health.

  1. Assessment of alpha activity of building materials commonly used in West Bengal, India

    International Nuclear Information System (INIS)

    Ghosh, Dipak; Deb, Argha; Bera, Sukumar; Sengupta, Rosalima; Patra, Kanchan Kumar

    2008-01-01

    This paper, reports for the first time, an extensive study of alpha activity of all widely used building materials (plaster of Paris, stone chips, marble, white cement, mosaic stone, limestone, sand, granite, cement brick, asbestos, red brick, cement tile, ceramic tile and ceramics) in West Bengal, India. The alpha activities have been measured using Solid State Nuclear Track Detector (SSNTD), a very sensitive detector for alpha particles. The samples were collected from local markets of Kolkata. The measured average alpha activities ranged from 22.7 ± 2.5 to 590.6 ± 16.8 Bq kg -1 . The alpha activity of ceramic tiles was highest and provides additional data to estimate the effect of environmental radiation exposure on human health

  2. Ultratrace determination of platinum in biological materials via neutron activation and radiochemical separation

    International Nuclear Information System (INIS)

    Zeisler, R.; Greenberg, R.R.

    1982-01-01

    A neutron activation analysis scheme based upon a radiochemical separation of the activation products has been developed. The method utilizes the inherent sensitivity of the activation reaction 198 Pt(n,ν) 199 Pt and counting of the daughter nuclide 199 Au. This nuclide is radiochemically separated from interfering activities by homogeneous precipitation as elemental gold. The remaining interference of the secondary reaction 197 Au(n,ν) 198 Au(n,ν) 199 Au from gold in the samples is quantitatively assessed and corrected. During this process accurate gold concentrations in the samples are obtained at ultratrace levels. The analysis scheme is applied to gold and platinum determinations in biological Standard Reference Materials and human liver specimens. Gold and platinum are determined at concentrations of 5x10 - 11 g/g, and at higher levels. (author)

  3. Determination of cadmium in environmental materials by fast neutron activation analysis

    International Nuclear Information System (INIS)

    Esprit, M.; Vandecasteele, C.; Hoste, J.

    1986-01-01

    Cadmium is determined by activation analysis with fast neutrons, obtained by irradiation of a thick beryllium target with 14.5-MeV deuterons. Cadmium-111m is separated by liquid-liquid extraction with zinc diethyldithiocarbamate in chloroform and measured with a Ge(Li) γ-spectrometer. For low concentrations, cadmium is precipitated as cadmium ammonium phosphate after the extraction. NBS and BCR reference materials were analyzed: for concentrations between 3 and 500 μg g -1 , the relative standard deviation ranges from 5 to 3%. The results obtained for sewage sludge are compared with those obtained by reactor neutron activation analysis. (Auth.)

  4. The problem of large samples. An activation analysis study of electronic waste material

    International Nuclear Information System (INIS)

    Segebade, C.; Goerner, W.; Bode, P.

    2007-01-01

    Large-volume instrumental photon activation analysis (IPAA) was used for the investigation of shredded electronic waste material. Sample masses from 1 to 150 grams were analyzed to obtain an estimate of the minimum sample size to be taken to achieve a representativeness of the results which is satisfactory for a defined investigation task. Furthermore, the influence of irradiation and measurement parameters upon the quality of the analytical results were studied. Finally, the analytical data obtained from IPAA and instrumental neutron activation analysis (INAA), both carried out in a large-volume mode, were compared. Only parts of the values were found in satisfactory agreement. (author)

  5. Neutron activation determination of oxygen in ceramic materials on the basis of yttrium, barium and copper

    International Nuclear Information System (INIS)

    Goldshtein, M.M.; Yudelevich, I.G.

    1991-01-01

    A procedure of determining oxygen in superconducting materials on the basis of yttrium, barium and copper oxides with the application of 14 MeV-neutron activation was developed. The method is based on determining the relation between oxygen and yttrium in the compounds investigated. In order to minimize systematic errors, expressions accounting for spectrometer dead time under conditions of varying component activity are proposed. The procedure ensures determination of the relation between oxygen and yttrium with a relative error of 0.4% with NAA using a neutron generator. (author) 4 refs.; 1 fig

  6. Photo-induced optical activity in phase-change memory materials.

    Science.gov (United States)

    Borisenko, Konstantin B; Shanmugam, Janaki; Williams, Benjamin A O; Ewart, Paul; Gholipour, Behrad; Hewak, Daniel W; Hussain, Rohanah; Jávorfi, Tamás; Siligardi, Giuliano; Kirkland, Angus I

    2015-03-05

    We demonstrate that optical activity in amorphous isotropic thin films of pure Ge2Sb2Te5 and N-doped Ge2Sb2Te5N phase-change memory materials can be induced using rapid photo crystallisation with circularly polarised laser light. The new anisotropic phase transition has been confirmed by circular dichroism measurements. This opens up the possibility of controlled induction of optical activity at the nanosecond time scale for exploitation in a new generation of high-density optical memory, fast chiroptical switches and chiral metamaterials.

  7. Electrosynthesis and catalytic activity of polymer-nickel particles composite electrode materials

    International Nuclear Information System (INIS)

    Melki, Tahar; Zouaoui, Ahmed; Bendemagh, Barkahoum; Oliveira, Ione M.F. de; Oliveira, Gilver F. de; Lepretre, Jean-Claude; Bucher, Christophe; Mou tet, Jean-Claude

    2009-01-01

    Nickel-polymer composite electrode materials have been synthesized using various strategies, all comprising the electrochemical reduction of nickel(II) cations or complexes, incorporated by either ion-exchange or complexation into various poly(pyrrole-carboxylate) thin films coated by oxidative electropolymerization onto carbon electrodes. The electrocatalytic activity and the stability of the different composites have been then evaluated in the course of the electrocatalytic hydrogenation of ketones and enones in aqueous electrolytes. The best results were obtained using nickel-polymer composites synthesized by electroreduction of nickel(II) ions complexed into polycarboxylate films, which are characterized by a high catalytic activity and a good operational stability. (author)

  8. Electrosynthesis and catalytic activity of polymer-nickel particles composite electrode materials

    Energy Technology Data Exchange (ETDEWEB)

    Melki, Tahar; Zouaoui, Ahmed; Bendemagh, Barkahoum [Universite Ferhat Abbas, Setif (Algeria). Faculte des Sciences de l' Ingenieur. Dept. du Tronc Commun; Oliveira, Ione M.F. de; Oliveira, Gilver F. de [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Quimica; Lepretre, Jean-Claude [UMR-5631 CNRS-INPG-UJF, St. Martin d' Heres Cedex (France). Lab. d' Electrochimie et de Physicochimie des Materiaux et Interfaces; Bucher, Christophe; Mou tet, Jean-Claude [Universite Joseph Fourier Grenoble 1 (France). Dept. de Chimie Moleculaire], e-mail: Jean-Claude.Moutet@ujf-grenoble.fr

    2009-07-01

    Nickel-polymer composite electrode materials have been synthesized using various strategies, all comprising the electrochemical reduction of nickel(II) cations or complexes, incorporated by either ion-exchange or complexation into various poly(pyrrole-carboxylate) thin films coated by oxidative electropolymerization onto carbon electrodes. The electrocatalytic activity and the stability of the different composites have been then evaluated in the course of the electrocatalytic hydrogenation of ketones and enones in aqueous electrolytes. The best results were obtained using nickel-polymer composites synthesized by electroreduction of nickel(II) ions complexed into polycarboxylate films, which are characterized by a high catalytic activity and a good operational stability. (author)

  9. Neutron induced activation in the EVEDA accelerator materials: Implications for the accelerator maintenance

    International Nuclear Information System (INIS)

    Sanz, J.; Garcia, M.; Sauvan, P.; Lopez, D.; Moreno, C.; Ibarra, A.; Sedano, L.

    2009-01-01

    The Engineering Validation and Engineering Design Activities (EVEDA) phase of the International Fusion Materials Irradiation Facility project should result in an accelerator prototype for which the analysis of the dose rates evolution during the beam-off phase is a necessary task for radioprotection and maintenance feasibility purposes. Important aspects of the computational methodology to address this problem are discussed, and dose rates for workers inside the accelerator vault are assessed and found to be not negligible.

  10. Initial testing of a neutron activation analysis system by analysing standard reference materials

    International Nuclear Information System (INIS)

    Suhaimi Hamzah; Roslan Idris; Abdul Khalik Haji Wood; Che Seman Mahmood; Abdul Rahim Mohamad Noor.

    1983-01-01

    This paper describes the data acquisition and processing system in our laboratories (ND6600), the methods of activation analysis and the results obtained from our analysis of IAEA standard reference material (SL-l lake sediments and NBS coal ash 1632a). These standards were analysed in order to check the capability of the system, which was designed in such a way as to enable the user to independently collect and process data from multiple radiation detectors. (author)

  11. Energetic materials research and development activities at Sandia National Laboratories supported under DP-10 programs

    Energy Technology Data Exchange (ETDEWEB)

    Ratzel, A.C. III

    1998-09-01

    This report provides summary descriptions of Energetic Materials (EM) Research and Development activities performed at Sandia National Laboratories and funded through the Department of Energy DP-10 Program Office in FY97 and FY98. The work falls under three major focus areas: EM Chemistry, EM Characterization, and EM Phenomenological Model Development. The research supports the Sandia component mission and also Sandia's overall role as safety steward for the DOE Nuclear Weapons Complex.

  12. Neutron activation analysis of reference materials by the k sub 0 standardization and relative methods

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, M C; Martinho, E [LNETI/ICEN, Sacavem (Portugal)

    1989-04-15

    Instrumental neutron activation analysis with the k{sub o}-standardization method was applied to eight geological, environmental and biological reference materials, including leaves, blood, fish, sediments, soils and limestone. To a first approximation, the results were normally distributed around the certified values with a standard deviation of 10%. Results obtained by using the relative method based on well characterized multi-element standards for IAEA CRM Soil-7 are reported.

  13. Determination of noble metals in geological materials by radiochemical neutron-activation analysis

    International Nuclear Information System (INIS)

    Ahmad, I.; Ahmad, S.; Morris, D.F.C.

    1977-01-01

    A method for the determination of platinum, palladium, gold and iridium in geological materials following activation with thermal neutrons is described. Radionuclides formed from the elements are separated by a scheme based largely on liquid-liquid extractions. The procedure has been applied to the analysis of US Geological Survey standard rocks and to studies of the distribution of the noble metals in lateritic nickel ores. (author)

  14. Neutron induced activation in the EVEDA accelerator materials: Implications for the accelerator maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, J. [Department of Power Engineering, Universidad Nacional de Educacion a Distancia (UNED), C/Juan del Rosal 12, 28040 Madrid (Spain); Institute of Nuclear Fusion, UPM, 28006 Madrid (Spain)], E-mail: jsanz@ind.uned.es; Garcia, M.; Sauvan, P.; Lopez, D. [Department of Power Engineering, Universidad Nacional de Educacion a Distancia (UNED), C/Juan del Rosal 12, 28040 Madrid (Spain); Institute of Nuclear Fusion, UPM, 28006 Madrid (Spain); Moreno, C.; Ibarra, A.; Sedano, L. [CIEMAT, 28040 Madrid (Spain)

    2009-04-30

    The Engineering Validation and Engineering Design Activities (EVEDA) phase of the International Fusion Materials Irradiation Facility project should result in an accelerator prototype for which the analysis of the dose rates evolution during the beam-off phase is a necessary task for radioprotection and maintenance feasibility purposes. Important aspects of the computational methodology to address this problem are discussed, and dose rates for workers inside the accelerator vault are assessed and found to be not negligible.

  15. Purely organic thermally activated delayed fluorescence (TADF) materials for organic light-emitting diodes (OLEDs)

    OpenAIRE

    Wong, Michael Y.; Zysman-Colman, Eli

    2017-01-01

    We thank the University of St Andrews for support. EZ-C thanks the Leverhulme Trust for financial support (RPG-2016-047). and the EPSRC (EP/P010482/1) for financial support. The design of thermally activated delayed fluorescence (TADF) materials both as emitters and as hosts is an exploding area of research. The replacement of phosphorescent metal complexes with inexpensive organic compounds in electroluminescent (EL) devices that demonstrate comparable performance metrics is paradigm shif...

  16. Programmatic material on perfection of competition activity of highly skilled basketball players.

    Directory of Open Access Journals (Sweden)

    Sushko Ruslana Aleksandrovna

    2011-09-01

    Full Text Available The special facilities are considered for creation of the programs of correction of training process and perfection of competitiveness activity. Basic estimations and structure of correction of technical tactical actions are resulted. It is set that programmatic material must take into account playing specialization of basketball-player, model indexes. It is also necessary to take into account optimization and modification of existent technologies of estimation of technical tactical actions.

  17. Capability Study For Using the Impulse Graphite Reactor For Activation Analysis of Geological Materials

    International Nuclear Information System (INIS)

    Azarov, V.A.; Silaev, M.E.

    1998-01-01

    The IGR reactor facility available in the Institute of Atomic Energy NNC RK is mainly used for testing the going and newly developed fuel compositions and reactor materials. In connection with a decrease of the demand in investigations like that there was considered the capability to use the reactor for solving another research and, particularly, applied problems. A mineral exploration is one of the urgent objectives in the Republic of Kazakstan, and in Semipalatinsk region in particular. To perform the exploration like that it's required, in addition to rough field investigations, the methods of analysis for element composition of geological materials, the difference of which is in their effectiveness, quality and low first cost. Activation methods of analysis allow to provide with a high analysis quality and effectiveness. Therefore, there was proposed to study the capability to use the IGR reactor for the activation analysis of geological materials. To solve this goal the following activity in three basic trends is required: 1. To create the needed theoretical and, on its basis, the methodical base for performing the analytical activity; 2. To create the experimental and technical and organizational infrastructure for the investigations, providing with a high productivity and low prime cost of work; 3. To conduct works on marketing and to use the going methodical and technical base on the market of services. Major objectives for the creation of the theoretical and methodical base for analysis are: a) the study of neutron and physical IGR reactor characteristics under various operation modes; b) the study of the radiation effect on the results of activation analysis; c) the simulation of the temperature mode for irradiation of samples in the reactor and experimental model survey; d) the study of the capability to use non-traditional elements and materials as neutron reactor flux monitors; e) the development of the technique for the experimental and computational

  18. Gamma activity as a guide for the building raw materials selection and controlling the environmental hazards

    Directory of Open Access Journals (Sweden)

    T. Ibrahim

    2012-06-01

    Full Text Available The spectrometric measurements can provide an alarm for the radiation activity and radioelement concentra-tions. The activity increase over the ambient background can be achieved by well calibrated gamma-spectrometers. In comparison between Wadi El-Dahl and Abu Zawal quarries for building raw materials (feld-spar, the activity concentration of El-Dahl stream sediments are 54.5 and 44.5 Bq/kg for uranium and thorium respectively. While the activity concentration of Abu Zawal rock quarry are 167.03 and 79.77 Bq/kg for uranium and thorium respectively. These activities yielding effective dose rates of 0.63 mSv/y for Wadi El-Dahl stream sediments and 1.48 mSv/y for Abu Zawal rock quarry. In summary, the spectrometric measurements are excellent selective tool to monitoring the environment against the radiation risk. In this aspect, Wadi El-Dahl stream sedi-ment quarry considered as the more suitable for producing feldspar as a raw materials to building industry. In comparison, Abu Zawal rock quarry has a higher effective dose rate exceeds the international permissible limits which is 1 mSv/y. A total of 19 feldspar samples were completely described regarding their general chemical fea-tures by using x-ray fluorescence. From the study all the samples contain high concentration of barium and ru-bidium which can separate using different methods in order to use in different important industry.

  19. Broad spectrum antibacterial and antifungal polymeric paint materials: synthesis, structure-activity relationship, and membrane-active mode of action.

    Science.gov (United States)

    Hoque, Jiaul; Akkapeddi, Padma; Yadav, Vikas; Manjunath, Goutham B; Uppu, Divakara S S M; Konai, Mohini M; Yarlagadda, Venkateswarlu; Sanyal, Kaustuv; Haldar, Jayanta

    2015-01-28

    Microbial attachment and subsequent colonization onto surfaces lead to the spread of deadly community-acquired and hospital-acquired (nosocomial) infections. Noncovalent immobilization of water insoluble and organo-soluble cationic polymers onto a surface is a facile approach to prevent microbial contamination. In the present study, we described the synthesis of water insoluble and organo-soluble polymeric materials and demonstrated their structure-activity relationship against various human pathogenic bacteria including drug-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and beta lactam-resistant Klebsiella pneumoniae as well as pathogenic fungi such as Candida spp. and Cryptococcus spp. The polymer coated surfaces completely inactivated both bacteria and fungi upon contact (5 log reduction with respect to control). Linear polymers were more active and found to have a higher killing rate than the branched polymers. The polymer coated surfaces also exhibited significant activity in various complex mammalian fluids such as serum, plasma, and blood and showed negligible hemolysis at an amount much higher than minimum inhibitory amounts (MIAs). These polymers were found to have excellent compatibility with other medically relevant polymers (polylactic acid, PLA) and commercial paint. The cationic hydrophobic polymer coatings disrupted the lipid membrane of both bacteria and fungi and thus showed a membrane-active mode of action. Further, bacteria did not develop resistance against these membrane-active polymers in sharp contrast to conventional antibiotics and lipopeptides, thus the polymers hold great promise to be used as coating materials for developing permanent antimicrobial paint.

  20. Antibacterial Activity of Hydrophobic Composite Materials Containing a Visible-Light-Sensitive Photocatalyst

    Directory of Open Access Journals (Sweden)

    Kentaro Yamauchi

    2011-01-01

    Full Text Available The conventional superhydrophobic surface offered by PTFE provides no sterilization performance and is not sufficiently repellent against organic liquids. These limit PTFE's application in the field of disinfection and result a lack of durability. N-doped TiO2 photocatalyst added PTFE composite material was developed to remedy these shortcomings. This paper reports the surface characteristics, and the bactericidal and self-cleaning performance of the newly-developed composite material. The material exhibited a contact angle exceeding 150 degrees consistent with its hydrophobicity despite the inclusion of the hydrophilic N-doped TiO2. The surface free energy obtained for this composite was 5.8 mN/m. Even when exposed to a weak fluorescent light intensity (100 lx for 24 hours, the viable cells of gram-negative E. coli on the 12% N-doped TiO2-PTFE film were reduced 5 logs. The higher bactericidal activity was also confirmed on the gram-positive MRSA. Compared with the N-doped TiO2 coating only, the inactivation rate of the composite material was significantly enhanced. Utilizing the N-doped TiO2 with the PTFE composite coating could successfully remove, by UV illumination, oleic acid adsorbed on its surface. These results demonstrate the potential applicability of the novel N-doped TiO2 photocatalyst hydrophobic composite material for both indoor antibacterial action and outdoor contamination prevention.

  1. Reuse of low specific activity material as part of LLWR design optimisation

    International Nuclear Information System (INIS)

    Huntington, Amy; Cummings, Richard; Shevelan, John; Sumerling, Trevor; Baker, Andrew J.

    2013-01-01

    A final cap will be emplaced over the disposed waste as part of the closure engineering for the UK's Low Level Waste Repository (LLWR). Additional profiling material will be required above the waste to obtain the required land-form. Consideration has been given to the potential opportunity to reuse Low Specific Activity Material (LSAM, defined as up to 200 Bq g -1 ) imported from other sites as a component of the necessary profiling material for the final repository cap. Justification of such a strategy would ultimately require a demonstration that the solution is optimal with respect to other options for the long-term management of such materials. The proposal is currently at the initial evaluation stage and seeks to establish how LSAM reuse within the cap could be achieved within the framework of an optimised safety case for the LLWR, should such a management approach be pursued. The key considerations include the following: The LSAM must provide the same engineering function as the remainder of the profiling material. The cap design must ensure efficient leachate collection, drainage and control for Low Level Waste (LLW) (and, by extension, LSAM) during the Period of Authorisation. In the longer term the engineering design must passively direct any accumulating waters preferentially away from surface water systems. An initial design has been developed that would allow the placement of around 220,000 m 3 of LSAM. The potential impact of the proposal has been assessed against the current Environmental Safety Case. (authors)

  2. Critical Dimensions of Water-tamped Slabs and Spheres of Active Material

    Science.gov (United States)

    Greuling, E.; Argo, H.: Chew, G.; Frankel, M. E.; Konopinski, E.J.; Marvin, C.; Teller, E.

    1946-08-06

    The magnitude and distribution of the fission rate per unit area produced by three energy groups of moderated neutrons reflected from a water tamper into one side of an infinite slab of active material is calculated approximately in section II. This rate is directly proportional to the current density of fast neutrons from the active material incident on the water tamper. The critical slab thickness is obtained in section III by solving an inhomogeneous transport integral equation for the fast-neutron current density into the tamper. Extensive use is made of the formulae derived in "The Mathematical Development of the End-Point Method" by Frankel and Goldberg. In section IV slight alterations in the theory outlined in sections II and III were made so that one could approximately compute the critical radius of a water-tamper sphere of active material. The derived formulae were applied to calculate the critical dimensions of water-tamped slabs and spheres of solid UF{sub 6} leaving various (25) isotope enrichment fractions. Decl. Dec. 16, 1955.

  3. Managing nuclear knowledge: IAEA activities and international coordination. Including resource material full text CD-ROM

    International Nuclear Information System (INIS)

    2005-06-01

    The present CD-ROM summarizes some activities carried out by the Departments of Nuclear Energy and Nuclear Safety and Security in the area of nuclear knowledge management in the period 2003-2005. It comprises, as open resource, most of the relevant documents in full text, including policy level documents, reports, presentation material by Member States and meeting summaries. The collection starts with a reprint of the report to the IAEA General Conference 2004 on Nuclear Knowledge [GOV/2004/56-GC(48)/12] summarizing the developments in nuclear knowledge management since the 47th session of the General Conference in 2003 and covers Managing Nuclear Knowledge including safety issues and Information and Strengthening Education and Training for Capacity Building. It contains an excerpt on Nuclear Knowledge from the General Conference Resolution [GC(48)/RES/13] on Strengthening the Agency's Activities Related to Nuclear Science, Technology and Applications. On the CD-ROM itself, all documents can easily be accessed by clicking on their titles on the subject pages (also printed at the end of this Working Material). Part 1 of the CD-ROM covers the activities in the period 2003-2005 and part 2 presents a resource material full text CD-ROM on Managing Nuclear Knowledge issued in October 2003

  4. Kinetic studies of potassium permanganate adsorption by activated carbon and its ability as ethylene oxidation material

    Science.gov (United States)

    Aprilliani, F.; Warsiki, E.; Iskandar, A.

    2018-03-01

    Generally, ethylene production in many horticultural products has been seen to be detrimental to the quality during storage and distribution process. For this reason, removing ethylene from storage or distribution atmosphere is needed to maintain the quality. One of the technologies that can be applied is the use of potassium permanganate (KMnO4). KMnO4 is an active compound that can be used as an oxidizing agent on ethylene removal process. KMnO4 is not recommended for direct used application. As the result, additional material is required to impregnate the potassium permanganate. The inert materials used are commercial activated carbon. Activated carbon is chosen because it has high surface area. The purpose of this research is to determine kinetics adsorption and oxidation model of ethylene removal material. The kinetics adsorption was determined using the pseudo-first and second-order kinetic models. The data on adsorption process show that the second-order equation is more suitable to express the adsorption process on this research. The analyzing of the ethylene oxidation capacity increased with time until it reaches an optimal value. The ethylene oxidation rate is able to be estimated by the formula r = 0.1967 [C2H4]0.99 [KMnO4]0.01; MSE = 0.44 %. The actual and estimation data of ethylene oxidation show that the model is fitted to describe the actual ethylene oxidation under same experimental conditions.

  5. Sol-Gel Derived Active Material for Yb Thin-Disk Lasers.

    Science.gov (United States)

    Almeida, Rui M; Ribeiro, Tiago; Santos, Luís F

    2017-09-02

    A ytterbium doped active material for thin-disk laser was developed based on aluminosilicate and phosphosilicate glass matrices containing up to 30 mol% YbO 1.5 . Thick films and bulk samples were prepared by sol-gel processing. The structural nature of the base material was assessed by X-ray diffraction and Raman spectroscopy and the film morphology was evidenced by scanning electron microscopy. The photoluminescence (PL) properties of different compositions, including emission spectra and lifetimes, were also studied. Er 3+ was used as an internal reference to compare the intensities of the Yb 3+ PL peaks at ~ 1020 nm. The Yb 3+ PL lifetimes were found to vary between 1.0 and 0.5 ms when the Yb concentration increased from 3 to 30 mol%. Based on a figure of merit, the best active material selected was the aluminosilicate glass composition 71 SiO₂-14 AlO 1.5 -15 YbO 1.5 (in mol%). An active disk, ~ 36 μm thick, consisting of a Bragg mirror, an aluminosilicate layer doped with 15 mol% Yb and an anti-reflective coating, was fabricated.

  6. Short communication: Effect of active food packaging materials on fluid milk quality and shelf life.

    Science.gov (United States)

    Wong, Dana E; Goddard, Julie M

    2014-01-01

    Active packaging, in which active agents are embedded into or on the surface of food packaging materials, can enhance the nutritive value, economics, and stability of food, as well as enable in-package processing. In one embodiment of active food packaging, lactase was covalently immobilized onto packaging films for in-package lactose hydrolysis. In prior work, lactase was covalently bound to low-density polyethylene using polyethyleneimine and glutaraldehyde cross-linkers to form the packaging film. Because of the potential contaminants of proteases, lipases, and spoilage organisms in typical enzyme preparations, the goal of the current work was to determine the effect of immobilized-lactase active packaging technology on unanticipated side effects, such as shortened shelf-life and reduced product quality. Results suggested no evidence of lipase or protease activity on the active packaging films, indicating that such active packaging films could enable in-package lactose hydrolysis without adversely affecting product quality in terms of dairy protein or lipid stability. Storage stability studies indicated that lactase did not migrate from the film over a 49-d period, and that dry storage resulted in 13.41% retained activity, whereas wet storage conditions enabled retention of 62.52% activity. Results of a standard plate count indicated that the film modification reagents introduced minor microbial contamination; however, the microbial population remained under the 20,000 cfu/mL limit through the manufacturer's suggested 14-d storage period for all film samples. This suggests that commercially produced immobilized lactase active packaging should use purified cross-linkers and enzymes. Characterization of unanticipated effects of active packaging on food quality reported here is important in demonstrating the commercial potential of such technologies. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  7. High Gain Advanced GPS Receiver

    National Research Council Canada - National Science Library

    Brown, Alison; Zhang, Gengsheng

    2006-01-01

    NAVSYS High Gain Advanced GPS Receiver (HAGR) uses a digital beam-steering antenna array to enable up to eight GPS satellites to be tracked, each with up to 10 dBi of additional antenna gain over a conventional receiver solution...

  8. Active material, optical mode and cavity impact on nanoscale electro-optic modulation performance

    Science.gov (United States)

    Amin, Rubab; Suer, Can; Ma, Zhizhen; Sarpkaya, Ibrahim; Khurgin, Jacob B.; Agarwal, Ritesh; Sorger, Volker J.

    2017-10-01

    Electro-optic modulation is a key function in optical data communication and possible future optical compute engines. The performance of modulators intricately depends on the interaction between the actively modulated material and the propagating waveguide mode. While a variety of high-performance modulators have been demonstrated, no comprehensive picture of what factors are most responsible for high performance has emerged so far. Here we report the first systematic and comprehensive analytical and computational investigation for high-performance compact on-chip electro-optic modulators by considering emerging active materials, model considerations and cavity feedback at the nanoscale. We discover that the delicate interplay between the material characteristics and the optical mode properties plays a key role in defining the modulator performance. Based on physical tradeoffs between index modulation, loss, optical confinement factors and slow-light effects, we find that there exist combinations of bias, material and optical mode that yield efficient phase or amplitude modulation with acceptable insertion loss. Furthermore, we show how material properties in the epsilon near zero regime enable reduction of length by as much as by 15 times. Lastly, we introduce and apply a cavity-based electro-optic modulator figure of merit, Δλ/Δα, relating obtainable resonance tuning via phase shifting relative to the incurred losses due to the fundamental Kramers-Kronig relations suggesting optimized device operating regions with optimized modulation-to-loss tradeoffs. This work paves the way for a holistic design rule of electro-optic modulators for high-density on-chip integration.

  9. Novel measurement method of activation energy of non-metallic materials for NPP

    International Nuclear Information System (INIS)

    Park, Chang-Dae; Lim, Byung-Ju; Song, Chi-Sung

    2008-01-01

    This paper presents novel technique and its applicability for measuring activation energy of non-metallic materials for NPPs (nuclear power plants). The E a is a principal property for life assessment and accelerating thermal aging of equipment during environmental qualification. The E a is conventionally obtained by tensile test using UTM (Universal Testing Machine). However, this conventional method has many difficulties such as lots of big standardized specimens required and long measuring time of at least 3 months. Moreover, this is not only an inapplicable method during inservice inspection but destructive method, which are main obstacles for using UTM. Fortunately, newly developed technique for the E a such as TGA (Thermo-gravimetric Analysis) and DMA (Dynamic Mechanical Analysis) can eliminate almost all the problems of UTM. The common TGA is to measure weight change with time under constant heating rate. TGA was devised to perform the compositional analysis of materials such as rubber, carbon black, filler, volatile, etc., and to determine the thermal stability/decomposition, stoichiometry of reactions, and kinetics of reaction, by weight changes of materials when heated. TGA method has various advantages such as small amount of the sample (e.g. 20 mg), shortened measuring time of approximately 2 days, and virtually non-destructive method. In this study, we have tried to find the justification of TGA utilization for E a measurement by comparing the measured TGA data to UTM data for three cable materials. Considering reasonable consistency of our TGA data with UTM data, we conclude that TGA method gives convenient way to measure the activation energy for EPR, CR, and CSP materials with many merits, such as measuring time, specimen size and quantity required, and test expenses. (author)

  10. Assessment of Uncertainty in the Determination of Activation Energy for Polymeric Materials

    Science.gov (United States)

    Darby, Stephania P.; Landrum, D. Brian; Coleman, Hugh W.

    1998-01-01

    An assessment of the experimental uncertainty in obtaining the kinetic activation energy from thermogravimetric analysis (TGA) data is presented. A neat phenolic resin, Borden SC1O08, was heated at three heating rates to obtain weight loss vs temperature data. Activation energy was calculated by two methods: the traditional Flynn and Wall method based on the slope of log(q) versus 1/T, and a modification of this method where the ordinate and abscissa are reversed in the linear regression. The modified method produced a more accurate curve fit of the data, was more sensitive to data nonlinearity, and gave a value of activation energy 75 percent greater than the original method. An uncertainty analysis using the modified method yielded a 60 percent uncertainty in the average activation energy. Based on this result, the activation energy for a carbon-phenolic material was doubled and used to calculate the ablation rate In a typical solid rocket environment. Doubling the activation energy increased surface recession by 3 percent. Current TGA data reduction techniques that use the traditional Flynn and Wall approach to calculate activation energy should be changed to the modified method.

  11. Plasmonic modulator based on gain-assisted metal-semiconductor-metal waveguide

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia E.; Kulkova, Irina V.; Malureanu, Radu

    2012-01-01

    . The modulation is achieved by changing the gain of the core that results in different transmittance through the waveguides. A MSM waveguide enables high field localization and therefore high modulation speed. Bulk semiconductor, quantum wells and quantum dots, arranged in either horizontal or vertical layout......, are considered as the core of the MSM waveguide. Dependences on the waveguide core size and gain values of various active materials are studied. The designs consider also practical aspects like n- and p-doped layers and barriers in order to obtain results as close to reality. The effective propagation constants...

  12. Examining porous bio-active glass as a potential osteo-odonto-keratoprosthetic skirt material.

    Science.gov (United States)

    Huhtinen, Reeta; Sandeman, Susan; Rose, Susanna; Fok, Elsie; Howell, Carol; Fröberg, Linda; Moritz, Niko; Hupa, Leena; Lloyd, Andrew

    2013-05-01

    Bio-active glass has been developed for use as a bone substitute with strong osteo-inductive capacity and the ability to form strong bonds with soft and hard tissue. The ability of this material to enhance tissue in-growth suggests its potential use as a substitute for the dental laminate of an osteo-odonto-keratoprosthesis. A preliminary in vitro investigation of porous bio-active glass as an OOKP skirt material was carried out. Porous glass structures were manufactured from bio-active glasses 1-98 and 28-04 containing varying oxide formulation (1-98, 28-04) and particle size range (250-315 μm for 1-98 and 28-04a, 315-500 μm for 28-04b). Dissolution of the porous glass structure and its effect on pH was measured. Structural 2D and 3D analysis of porous structures were performed. Cell culture experiments were carried out to study keratocyte adhesion and the inflammatory response induced by the porous glass materials. The dissolution results suggested that the porous structure made out of 1-98 dissolves faster than the structures made from glass 28-04. pH experiments showed that the dissolution of the porous glass increased the pH of the surrounding solution. The cell culture results showed that keratocytes adhered onto the surface of each of the porous glass structures, but cell adhesion and spreading was greatest for the 98a bio-glass. Cytokine production by all porous glass samples was similar to that of the negative control indicating that the glasses do not induce a cytokine driven inflammatory response. Cell culture results support the potential use of synthetic porous bio-glass as an OOKP skirt material in terms of limited inflammatory potential and capacity to induce and support tissue ingrowth.

  13. Development of high performance and low radio activation concrete material for concrete cask

    International Nuclear Information System (INIS)

    Shirai, Koji; Sonobe, Ryoji

    2005-01-01

    For the realization of the long-term storage of the nuclear spent fuel with the concrete cask technology, a low radio activation high performance concrete was developed, which contains extremely small quantity of Eu and Co and assures enough heat-resistance and durability for degradation. Firstly, the activation analysis was performed to estimate the allowable content limit of their quantities according to the rules issued by Japanese government for determining the classification of the radioactive waste. Secondly, various candidate materials were sampled and irradiated to find out the activation level. As a result, as the optimum concrete mix, the combination of limestone and white fused alumina aggregates with fry-ash was chosen. Moreover, the basic characteristics of the candidate concrete (workability, strength under high temperature, heat conductivity and so on) were evaluated, and the thermal cracking test was executed with hollow cylinders. Finally, the developed concrete material seems to be suitable for the long-term use of concrete cask considering the low activation, high heat resistance and durability during storage. (author)

  14. Trace elements with large activation cross section in concrete materials in Japan

    International Nuclear Information System (INIS)

    Suzuki, Atsuo; Iida, Takao; Moriizumi, Jun; Sakuma, Yoichi; Takada, Jitsuya; Yamasaki, Keizo; Yoshimoto, Takaaki

    2001-01-01

    Amounts of trace elements with large activation cross section in concrete materials were measured to offer the basic data for developing of low activation concrete. From the measurements, the quantities of the activated radioactivities in biological shielding concrete were measured and evaluated for the clearance level. The average concentrations of 60 Co, 152 Eu and 134 Cs formed in concrete were 21.9, 1.08 and 3.21 ppm, respectively. The combination of the concrete materials for the most lowering concentrations of 60 Co, 152 Eu and 134 Cs was the limestone as aggregate and the white Portland cement produced in specific places. The most lowering concentrations of this limestone concrete were 0.16, 0.049 and 0.060 ppm, respectively. The limestone concrete was excellent as biological shielding concrete, because the neutron shielding effect was excellent a little compared with ordinary concrete. If this concrete used for biological shielding concrete, concrete waste will be able to handle as follows. Usage of this limestone low-activated concrete makes almost all concretes satisfy the clearance level for 60 Co after 20 yr cooling from decommissioning. In respect of 152 Eu, radioactivation quantity in the biological shielding concrete is reduced up to a half of the average value or less. With regard to 134 Cs, all concrete satisfies the clearance level. (author)

  15. Effect of gamma irradiation on fluoride release and antibacterial activity of resin dental materials

    International Nuclear Information System (INIS)

    Carvalho, Fabiola Galbiatti de; Fucio, Suzana Beatriz Portugal de; Correr-Sobrinho, Lourenco; Pascon, Fernanda Miori; Kantovitz, Kamila Rosamilia; Puppin-Rontani, Regina Maria

    2009-01-01

    This study evaluated the effect of gamma irradiation on fluoride release and antibacterial activity of FluroShield (FS) and Clearfil Protect Bond (CPB). Four groups were formed: G1-FS + gamma; G2-FS without gamma; G3-CPB + gamma; G4-CPB without gamma. For fluoride release analysis, 12 disks of each material were prepared and covered with nail polish, except for one side (50.4 mm 2 area). G1 and G3 were sterilized with a 14.5 KGy dose at 27 deg C for 24 h, while G2 and G4 (controls) were not sterilized and were maintained under the same time and temperature conditions. Fluoride release measurements were made in duplicate (n=6) by an ion specific electrode. The antibacterial activity of the CPB and FS against Streptococcus mutans after gamma sterilization was evaluated by the agar-disc diffusion method. The diameter of the zones of microbial growth inhibition was recorded after 48 h. Data were analyzed statistically by ANOVA and Tukey's test (alpha=5%). Gamma sterilization decreased the fluoride release of FS by approximately 50%, while CPB was not affected. There was no statistically significant difference (p>0.05) in the antibacterial effect of CPB between gamma and non-gamma sterilization groups. FS presented no antibacterial activity. Gamma irradiation decreased the fluoride release of FS, but did not affect the antibacterial activity of the studied materials. (author)

  16. Effect of gamma irradiation on fluoride release and antibacterial activity of resin dental materials

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fabiola Galbiatti de; Fucio, Suzana Beatriz Portugal de; Correr-Sobrinho, Lourenco [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Piracicaba Dental School. Dept. of Dental Materials; Pascon, Fernanda Miori; Kantovitz, Kamila Rosamilia; Puppin-Rontani, Regina Maria [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Piracicaba Dental School. Dept. of Pedriatric Dentistry], e-mail: rmpuppin@fop.unicamp.br

    2009-07-01

    This study evaluated the effect of gamma irradiation on fluoride release and antibacterial activity of FluroShield (FS) and Clearfil Protect Bond (CPB). Four groups were formed: G1-FS + gamma; G2-FS without gamma; G3-CPB + gamma; G4-CPB without gamma. For fluoride release analysis, 12 disks of each material were prepared and covered with nail polish, except for one side (50.4 mm{sup 2} area). G1 and G3 were sterilized with a 14.5 KGy dose at 27 deg C for 24 h, while G2 and G4 (controls) were not sterilized and were maintained under the same time and temperature conditions. Fluoride release measurements were made in duplicate (n=6) by an ion specific electrode. The antibacterial activity of the CPB and FS against Streptococcus mutans after gamma sterilization was evaluated by the agar-disc diffusion method. The diameter of the zones of microbial growth inhibition was recorded after 48 h. Data were analyzed statistically by ANOVA and Tukey's test (alpha=5%). Gamma sterilization decreased the fluoride release of FS by approximately 50%, while CPB was not affected. There was no statistically significant difference (p>0.05) in the antibacterial effect of CPB between gamma and non-gamma sterilization groups. FS presented no antibacterial activity. Gamma irradiation decreased the fluoride release of FS, but did not affect the antibacterial activity of the studied materials. (author)

  17. Photocatalytic activity of titanium dioxide modified concrete materials - influence of utilizing recycled glass cullets as aggregates.

    Science.gov (United States)

    Chen, Jun; Poon, Chi-Sun

    2009-08-01

    Combining the use of photocatalysts with cementitious materials is an important development in the field of photocatalytic air pollution mitigation. This paper presents the results of a systematic study on assessing the effectiveness of pollutant degradation by concrete surface layers that incorporate a photocatalytic material - Titanium Dioxide. The photocatalytic activity of the concrete samples was determined by photocatalytic oxidation of nitric oxide (NO) in the laboratory. Recycled glass cullets, derived from crushed waste beverage bottles, were used to replace sand in preparing the concrete surface layers. Factors, which may affect the pollutant removal performance of the concrete layers including glass color, aggregate size and curing age, were investigated. The results show a significant enhancement of the photocatalytic activity due to the use of glass cullets as aggregates in the concrete layers. The samples fabricated with clear glass cullets exhibited threefold NO removal efficiency compared to the samples fabricated with river sand. The light transmittance property of glass was postulated to account for the efficiency improvement, which was confirmed by a separate simulation study. But the influence of the size of glass cullets was not evident. In addition, the photocatalytic activity of concrete surface layers decreased with curing age, showing a loss of 20% photocatalytic activity after 56-day curing.

  18. Natural sisal fibers derived hierarchical porous activated carbon as capacitive material in lithium ion capacitor

    Science.gov (United States)

    Yang, Zhewei; Guo, Huajun; Li, Xinhai; Wang, Zhixing; Yan, Zhiliang; Wang, Yansen

    2016-10-01

    Lithium-ion capacitor (LIC) is a novel advanced electrochemical energy storage (EES) system bridging gap between lithium ion battery (LIB) and electrochemical capacitor (ECC). In this work, we report that sisal fiber activated carbon (SFAC) was synthesized by hydrothermal treatment followed by KOH activation and served as capacitive material in LIC for the first time. Different particle structure, morphology, specific surface area and heteroatoms affected the electrochemical performance of as-prepared materials and corresponding LICs. When the mass ratio of KOH to char precursor was 2, hierarchical porous structured SFAC-2 was prepared and exhibited moderate specific capacitance (103 F g-1 at 0.1 A g-1), superior rate capability and cyclic stability (88% capacity retention after 5000 cycles at 1 A g-1). The corresponding assembled LIC (LIC-SC2) with optimal comprehensive electrochemical performance, displayed the energy density of 83 Wh kg-1, the power density of 5718 W kg-1 and superior cyclic stability (92% energy density retention after 1000 cycles at 0.5 A g-1). It is worthwhile that the source for activated carbon is a natural and renewable one and the synthesis method is eco-friendly, which facilitate that hierarchical porous activated carbon has potential applications in the field of LIC and other energy storage systems.

  19. Synthesis, characterization and catalytic activity of acid-base bifunctional materials through protection of amino groups

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Yanqiu [College of Chemistry, Jilin University, Changchun 130023 (China); College of Chemistry, Mudanjiang Normal University, Mudanjiang 157012 (China); Liu, Heng; Yu, Xiaofang [College of Chemistry, Jilin University, Changchun 130023 (China); Guan, Jingqi, E-mail: guanjq@jlu.edu.cn [College of Chemistry, Jilin University, Changchun 130023 (China); Kan, Qiubin, E-mail: qkan@mail.jlu.edu.cn [College of Chemistry, Jilin University, Changchun 130023 (China)

    2012-03-15

    Graphical abstract: Acid-base bifunctional mesoporous material SO{sub 3}H-SBA-15-NH{sub 2} was successfully synthesized under low acidic medium through protection of amino groups. Highlights: Black-Right-Pointing-Pointer The acid-base bifunctional material SO{sub 3}H-SBA-15-NH{sub 2} was successfully synthesized through protection of amino groups. Black-Right-Pointing-Pointer The obtained bifunctional material was tested for aldol condensation. Black-Right-Pointing-Pointer The SO{sub 3}H-SBA-15-NH{sub 2} catalyst containing amine and sulfonic acid groups exhibited excellent acid-basic properties. -- Abstract: Acid-base bifunctional mesoporous material SO{sub 3}H-SBA-15-NH{sub 2} was successfully synthesized under low acidic medium through protection of amino groups. X-ray diffraction (XRD), N{sub 2} adsorption-desorption, transmission electron micrographs (TEM), back titration, {sup 13}C magic-angle spinning (MAS) NMR and {sup 29}Si magic-angle spinning (MAS) NMR were employed to characterize the synthesized materials. The obtained bifunctional material was tested for aldol condensation reaction between acetone and 4-nitrobenzaldehyde. Compared with monofunctional catalysts of SO{sub 3}H-SBA-15 and SBA-15-NH{sub 2}, the bifunctional sample of SO{sub 3}H-SBA-15-NH{sub 2} containing amine and sulfonic acid groups exhibited excellent acid-basic properties, which make it possess high activity for the aldol condensation.

  20. Research and development activities at INE concerning corrosion of final repository container materials

    International Nuclear Information System (INIS)

    Kienzler, Bernhard

    2017-01-01

    The present work provides a historical overview of the research and development activities carried out at the (Nuclear) Research Center Karlsruhe (today KIT) since the beginning of the 1980s on the corrosion of materials which might be suitable for construction of containers for highly radioactive wastes. The report relates almost exclusively to the work performed by Dr. Emmanuel Smailos, who elaborated the corrosion of various materials at the Institute for Nuclear Waste Disposal (INE). The requirements for the containers and materials, which were subject to changes in time, are presented. The changes were strongly influenced by the changed perception of the use of nuclear energy. The selection of the materials under investigations, the boundary conditions for the corrosion experiments and the analytical methods are described. Results of the corrosion of the materials such as finegrained steel, Hastelloy C4, nodular cast iron, titanium-palladium and copper or copper-nickel alloys in typical salt solutions are summarized. The findings of special investigations, e.g. corrosion under irradiation or the influence of sulfide on the corrosion rates are shown. For construction of disposal canisters, experiments were conducted to determine the contact corrosion, the influence of the hydrogen embrittlement of Ti-Pd and fine-grained steels on the corrosion behavior as well as the corrosion behavior of welding and the influence of different welding processes with the resulting heat-affected zones on the corrosion behavior. The work was contributed to several European research programs and was well recognized in the USA. Investigations on the corrosion of steels in non-saline solutions and corrosion under interim storage conditions as well as under the expected conditions of the Konrad repository for low-level radioactive wastes are also described. In addition, the experiments on ceramic materials are presented and the results of the corrosion of Al 2 O 3 and ZrO 2 ceramics