WorldWideScience

Sample records for band materials progress

  1. Photonic band gap materials

    Science.gov (United States)

    Cassagne, D.

    Photonic band gap materials Photonic band gap materials are periodic dielectric structures that control the propagation of electromagnetic waves. We describe the plane wave method, which allows to calculate the band structures of photonic crystals. By symmetry analysis and a perturbative approach, we predict the appearance of the low energy photonic band gaps of hexagonal structures. We propose new two-dimensional structures called graphite and boron nitride. Using a transfer matrix method, we calculate the transmission of the graphite structure and we show the crucial role of the coupling with external modes. We study the appearance of allowed modes in the photonic band gap by the introduction of localized defects in the periodicity. Finally, we discuss the properties of opals formed by self-organized silica microspheres, which are very promising for the fabrication of three-dimensional photonic crystals. Les matériaux à bandes interdites photoniques sont des structures diélectriques périodiques qui contrôlent la propagation des ondes électromagnétiques. Nous décrivons la méthode des ondes planes qui permet de calculer les structures de bandes des cristaux photoniques. Par une analyse de la symétrie et une approche perturbative, nous précisons les conditions d'existence des bandes interdites de basse énergie. Nous proposons de nouvelles structures bidimensionnelles appelées graphite et nitrure de bore. Grâce à une méthode de matrices de transfert, nous calculons la transmission de la structure graphite et nous mettons en évidence le rôle fondamental du couplage avec les modes extérieurs. Nous étudions l'apparition de modes permis dans la bande interdite grâce à l'introduction de défauts dans la périodicité. Enfin, nous discutons les propriétés des opales constituées de micro-billes de silice auto-organisées, qui sont très prometteuses pour la fabrication de cristaux photoniques tridimensionnels.

  2. Theoretical band alignment in an intermediate band chalcopyrite based material

    Science.gov (United States)

    Castellanos Águila, J. E.; Palacios, P.; Conesa, J. C.; Arriaga, J.; Wahnón, P.

    2017-12-01

    Band alignment is key to enhance the performance of heterojunction for chalcopyrite thin film solar cells. In this paper we report ab initio calculations of the electronic structures of CuGaS2:Cr with various Cr compositions, CuAlSe2 and ZnSe and the band alignment between their interfaces. We use density functional theory and the more accurate self-consistent GW scheme to obtain improved bulk band-gaps and band offsets. Band alignments of the interfacial region for CuGaS2:Cr/CuAlSe2 and CuGaS2:Cr/ZnSe systems were aligned with respect of an average electrostatic potential. Our results are in good agreement with experimental values for the bulk band-gaps. These theoretical band alignments show a characteristic staggered band alignment for the design of heterojunction devices in photovoltaic applications.

  3. Computational Design of Flat-Band Material

    Science.gov (United States)

    Hase, I.; Yanagisawa, T.; Kawashima, K.

    2018-02-01

    Quantum mechanics states that hopping integral between local orbitals makes the energy band dispersive. However, in some special cases, there are bands with no dispersion due to quantum interference. These bands are called as flat band. Many models having flat band have been proposed, and many interesting physical properties are predicted. However, no real compound having flat band has been found yet despite the 25 years of vigorous researches. We have found that some pyrochlore oxides have quasi-flat band just below the Fermi level by first principles calculation. Moreover, their valence bands are well described by a tight-binding model of pyrochlore lattice with isotropic nearest neighbor hopping integral. This model belongs to a class of Mielke model, whose ground state is known to be ferromagnetic with appropriate carrier doping and on-site repulsive Coulomb interaction. We have also performed a spin-polarized band calculation for the hole-doped system from first principles and found that the ground state is ferromagnetic for some doping region. Interestingly, these compounds do not include magnetic element, such as transition metal and rare-earth elements.

  4. Computational Design of Flat-Band Material.

    Science.gov (United States)

    Hase, I; Yanagisawa, T; Kawashima, K

    2018-02-26

    Quantum mechanics states that hopping integral between local orbitals makes the energy band dispersive. However, in some special cases, there are bands with no dispersion due to quantum interference. These bands are called as flat band. Many models having flat band have been proposed, and many interesting physical properties are predicted. However, no real compound having flat band has been found yet despite the 25 years of vigorous researches. We have found that some pyrochlore oxides have quasi-flat band just below the Fermi level by first principles calculation. Moreover, their valence bands are well described by a tight-binding model of pyrochlore lattice with isotropic nearest neighbor hopping integral. This model belongs to a class of Mielke model, whose ground state is known to be ferromagnetic with appropriate carrier doping and on-site repulsive Coulomb interaction. We have also performed a spin-polarized band calculation for the hole-doped system from first principles and found that the ground state is ferromagnetic for some doping region. Interestingly, these compounds do not include magnetic element, such as transition metal and rare-earth elements.

  5. FY2016 Lightweight Materials Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-10-31

    The Lightweight Materials research and development (R&D) area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing lightweight materials for passenger and commercial vehicles. This report describes the progress made on the research and development projects funded by the Lightweight Materials area.

  6. Metallic photonic band-gap materials

    International Nuclear Information System (INIS)

    Sigalas, M.M.; Chan, C.T.; Ho, K.M.; Soukoulis, C.M.

    1995-01-01

    We calculate the transmission and absorption of electromagnetic waves propagating in two-dimensional (2D) and 3D periodic metallic photonic band-gap (PBG) structures. For 2D systems, there is substantial difference between the s- and p-polarized waves. The p-polarized waves exhibit behavior similar to the dielectric PBG's. But, the s-polarized waves have a cutoff frequency below which there are no propagating modes. For 3D systems, the results are qualitatively the same for both polarizations but there are important differences related to the topology of the structure. For 3D structures with isolated metallic scatterers (cermet topology), the behavior is similar to that of the dielectric PBG's, while for 3D structures with the metal forming a continuous network (network topology), there is a cutoff frequency below which there are no propagating modes. The systems with the network topology may have some interesting applications for frequencies less than about 1 THz where the absorption can be neglected. We also study the role of the defects in the metallic structures

  7. Experimental study of shear bands formation in a granular material

    Directory of Open Access Journals (Sweden)

    Nguyen Thai Binh

    2017-01-01

    Full Text Available We present an experimental investigation of the formation of shear bands in a granular sample submitted to a biaxial test. Our principal result is the direct observation of the bifurcation at the origin of the localization process in the material. At the bifurcation, the shear band is spatially extended: we observe a breaking of symmetry without any sudden localization of the deformation in a narrow band. Our work thus allows to clearly distinguish different phenomena: bifurcation which is a ponctual event which occurs before the peak, localization which is a process that covers a range of deformation of several percents during which the peak occurs and finally stationary shear bands which are well-defined permanent structures that can be observed at the end of the localization process, after the peak.

  8. A bespoke single-band Hubbard model material

    Science.gov (United States)

    Griffin, S. M.; Staar, P.; Schulthess, T. C.; Troyer, M.; Spaldin, N. A.

    2016-02-01

    The Hubbard model, which augments independent-electron band theory with a single parameter to describe electron-electron correlations, is widely regarded to be the "standard model" of condensed-matter physics. The model has been remarkably successful at addressing a range of correlation phenomena in solids, but it neglects many behaviors that occur in real materials, such as phonons, long-range interactions, and, in its simplest form, multiorbital effects. Here, we use ab initio electronic structure methods to design a material whose Hamiltonian matches as closely as possible that of the single-band Hubbard model. Our motivation is to compare the measured properties of our new material to those predicted by reliable theoretical solutions of the Hubbard model to determine the relevance of the model in the description of real materials. After identifying an appropriate crystal class and several appropriate chemistries, we use density-functional theory and dynamical mean-field theory to screen for the desired electronic band structure and metal-insulator transition. We then explore the most promising candidates for structural stability and suitability for doping, and we propose specific materials for subsequent synthesis. Finally, we identify a regime—that should manifest in our bespoke material—in which the single-band Hubbard model on a triangular lattice exhibits exotic d -wave superconductivity.

  9. Tunable Intrinsic Plasmons due to Band Inversion in Topological Materials

    Science.gov (United States)

    Zhang, Furu; Zhou, Jianhui; Xiao, Di; Yao, Yugui

    2017-12-01

    Band inversion has led to rich physical effects in both topological insulators and topological semimetals. It has been found that the inverted band structure with the Mexican-hat dispersion could enhance the interband correlation leading to a strong intrinsic plasmon excitation. Its frequency ranges from several meV to tens of meV and can be effectively tuned by the external fields. The electron-hole asymmetric term splits the peak of the plasmon excitation into double peaks. The fate and properties of this plasmon excitation can also act as a probe to characterize the topological phases even in lightly doped systems. We numerically demonstrate the impact of band inversion on plasmon excitations in magnetically doped thin films of three-dimensional strong topological insulators, V- or Cr-doped (Bi ,Sb )2Te3 , which support the quantum anomalous Hall states. Our work thus sheds some new light on the potential applications of topological materials in plasmonics.

  10. On acoustic band gaps in homogenized piezoelectric phononic materials

    Directory of Open Access Journals (Sweden)

    Rohan E.

    2010-07-01

    Full Text Available We consider a composite medium made of weakly piezoelectric inclusions periodically distributed in the matrix which ismade of a different piezoelectricmaterial. Themediumis subject to a periodic excitation with an incidence wave frequency independent of scale ε of the microscopic heterogeneities. Two-scale method of homogenization is applied to obtain the limit homogenized model which describes acoustic wave propagation in the piezoelectric medium when ε → 0. In analogy with the purely elastic composite, the resulting model allows existence of the acoustic band gaps. These are identified for certain frequency ranges whenever the so-called homogenized mass becomes negative. The homogenized model can be used for band gap prediction and for dispersion analysis for low wave numbers. Modeling such composite materials seems to be perspective in the context of Smart Materials design.

  11. Fatigue failure of materials under broad band random vibrations

    Science.gov (United States)

    Huang, T. C.; Lanz, R. W.

    1971-01-01

    The fatigue life of material under multifactor influence of broad band random excitations has been investigated. Parameters which affect the fatigue life are postulated to be peak stress, variance of stress and the natural frequency of the system. Experimental data were processed by the hybrid computer. Based on the experimental results and regression analysis a best predicting model has been found. All values of the experimental fatigue lives are within the 95% confidence intervals of the predicting equation.

  12. Photonic band gap materials: design, synthesis, and applications

    International Nuclear Information System (INIS)

    John, S.

    2000-01-01

    Full text: Unlike semiconductors which facilitate the coherent propagation of electrons, photonic band gap (PBG) materials execute their novel functions through the coherent localization of photons. I review and discuss our recent synthesis of a large scale three-dimensional silicon photonic crystal with a complete photonic band gap near 1.5 microns. When a PBG material is doped with impurity atoms which have an electronic transition that lies within the gap, spontaneous emission of light from the atom is inhibited. Inside the gap, the photon forms a bound state to the atom. Outside the gap, radiative dynamics in the colored vacuum is highly non Markovian. I discuss the influence of these memory effects on laser action. When spontaneous emission is absent, the next order radiative effect (resonance dipole dipole interaction between atoms) must be incorporated leading to anomalous nonlinear optical effects which occur at a much lower threshold than in ordinary vacuum. I describe the collective switching of two-level atoms near a photonic band edge, by external laser field, from a passive state to one exhibiting population inversion. This effect is forbidden in ordinary vacuum. However, in the context of a PBG material, this effect may be utilized for an all-optical transistor. Finally, I discuss the prospects for a phase sensitive, single atom quantum memory device, onto which information may be written by an external laser pulse

  13. Electronic materials with a wide band gap: recent developments

    Directory of Open Access Journals (Sweden)

    Detlef Klimm

    2014-09-01

    Full Text Available The development of semiconductor electronics is reviewed briefly, beginning with the development of germanium devices (band gap Eg = 0.66 eV after World War II. A tendency towards alternative materials with wider band gaps quickly became apparent, starting with silicon (Eg = 1.12 eV. This improved the signal-to-noise ratio for classical electronic applications. Both semiconductors have a tetrahedral coordination, and by isoelectronic alternative replacement of Ge or Si with carbon or various anions and cations, other semiconductors with wider Eg were obtained. These are transparent to visible light and belong to the group of wide band gap semiconductors. Nowadays, some nitrides, especially GaN and AlN, are the most important materials for optical emission in the ultraviolet and blue regions. Oxide crystals, such as ZnO and β-Ga2O3, offer similarly good electronic properties but still suffer from significant difficulties in obtaining stable and technologically adequate p-type conductivity.

  14. Fatigue failure of materials under narrow band random vibrations. I.

    Science.gov (United States)

    Huang, T. C.; Hubbard, R. B.; Lanz, R. W.

    1971-01-01

    A novel approach for the study of fatigue failure of materials under the multifactor influence of narrow band random vibrations is developed. The approach involves the conduction of an experiment in conjunction with various statistical techniques. Three factors including two statistical properties of the excitation or response are considered and varied simultaneously. A minimum of 6 tests for 3 variables is possible for a fractional f actorial design. The four coefficients of the predicting equation can be independently estimated. A look at 3 predicting equations shows the predominant effect of the root mean square stress of the first order equation.

  15. Photonic band gap materials: Technology, applications and challenges

    International Nuclear Information System (INIS)

    Johri, M.; Ahmed, Y.A.; Bezboruah, T.

    2006-05-01

    Last century has been the age of Artificial Materials. One material that stands out in this regard is the semiconductor. The revolution in electronic industry in the 20th century was made possible by the ability of semiconductors to microscopically manipulate the flow of electrons. Further advancement in the field made scientists suggest that the new millennium will be the age of photonics in which artificial materials will be synthesized to microscopically manipulate the flow of light. One of these will be Photonic Band Gap material (PBG). PBG are periodic dielectric structures that forbid propagation of electromagnetic waves in a certain frequency range. They are able to engineer most fundamental properties of electromagnetic waves such as the laws of refraction, diffraction, and emission of light from atoms. Such PBG material not only opens up variety of possible applications (in lasers, antennas, millimeter wave devices, efficient solar cells photo-catalytic processes, integrated optical communication etc.) but also give rise to new physics (cavity electrodynamics, localization, disorder, photon-number-state squeezing). Unlike electronic micro-cavity, optical waveguides in a PBG microchip can simultaneously conduct hundreds of wavelength channels of information in a three dimensional circuit path. In this article we have discussed some aspects of PBG materials and their unusual properties, which provided a foundation for novel practical applications ranging from clinical medicine to information technology. (author)

  16. Band structures of 4f and 5f materials studied by angle-resolved photoelectron spectroscopy.

    Science.gov (United States)

    Fujimori, Shin-ichi

    2016-04-20

    Recent remarkable progress in angle-resolved photoelectron spectroscopy (ARPES) has enabled the direct observation of the band structures of 4f and 5f materials. In particular, ARPES with various light sources such as lasers (hν ~ 7 eV) or high-energy synchrotron radiations (hν >/~ 400 eV) has shed light on the bulk band structures of strongly correlated materials with energy scales of a few millielectronvolts to several electronvolts. The purpose of this paper is to summarize the behaviors of 4f and 5f band structures of various rare-earth and actinide materials observed by modern ARPES techniques, and understand how they can be described using various theoretical frameworks. For 4f-electron materials, ARPES studies of CeMIn5(M = Rh, Ir, and Co) and YbRh2Si2 with various incident photon energies are summarized. We demonstrate that their 4f electronic structures are essentially described within the framework of the periodic Anderson model, and that the band-structure calculation based on the local density approximation cannot explain their low-energy electronic structures. Meanwhile, electronic structures of 5f materials exhibit wide varieties ranging from itinerant to localized states. For itinerant U5f compounds such as UFeGa5, their electronic structures can be well-described by the band-structure calculation assuming that all U5f electrons are itinerant. In contrast, the band structures of localized U5f compounds such as UPd3 and UO2 are essentially explained by the localized model that treats U5f electrons as localized core states. In regards to heavy fermion U-based compounds such as the hidden-order compound URu2Si2, their electronic structures exhibit complex behaviors. Their overall band structures are generally well-explained by the band-structure calculation, whereas the states in the vicinity of EF show some deviations due to electron correlation effects. Furthermore, the electronic structures of URu2Si2 in the paramagnetic and hidden-order phases are

  17. High-Power Fiber Lasers Using Photonic Band Gap Materials

    Science.gov (United States)

    DiDomenico, Leo; Dowling, Jonathan

    2005-01-01

    High-power fiber lasers (HPFLs) would be made from photonic band gap (PBG) materials, according to the proposal. Such lasers would be scalable in the sense that a large number of fiber lasers could be arranged in an array or bundle and then operated in phase-locked condition to generate a superposition and highly directed high-power laser beam. It has been estimated that an average power level as high as 1,000 W per fiber could be achieved in such an array. Examples of potential applications for the proposed single-fiber lasers include welding and laser surgery. Additionally, the bundled fibers have applications in beaming power through free space for autonomous vehicles, laser weapons, free-space communications, and inducing photochemical reactions in large-scale industrial processes. The proposal has been inspired in part by recent improvements in the capabilities of single-mode fiber amplifiers and lasers to produce continuous high-power radiation. In particular, it has been found that the average output power of a single strand of a fiber laser can be increased by suitably changing the doping profile of active ions in its gain medium to optimize the spatial overlap of the electromagnetic field with the distribution of active ions. Such optimization minimizes pump power losses and increases the gain in the fiber laser system. The proposal would expand the basic concept of this type of optimization to incorporate exploitation of the properties (including, in some cases, nonlinearities) of PBG materials to obtain power levels and efficiencies higher than are now possible. Another element of the proposal is to enable pumping by concentrated sunlight. Somewhat more specifically, the proposal calls for exploitation of the properties of PBG materials to overcome a number of stubborn adverse phenomena that have impeded prior efforts to perfect HPFLs. The most relevant of those phenomena is amplified spontaneous emission (ASE), which causes saturation of gain and power

  18. Ultra Wide Band RFID Neutron Tags for Nuclear Materials Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Nekoogar, F; Dowla, F; Wang, T

    2010-01-27

    Recent advancements in the ultra-wide band Radio Frequency Identification (RFID) technology and solid state pillar type neutron detectors have enabled us to move forward in combining both technologies for advanced neutron monitoring. The LLNL RFID tag is totally passive and will operate indefinitely without the need for batteries. The tag is compact, can be directly mounted on metal, and has high performance in dense and cluttered environments. The LLNL coin-sized pillar solid state neutron detector has achieved a thermal neutron detection efficiency of 20% and neutron/gamma discrimination of 1E5. These performance values are comparable to a fieldable {sup 3}He based detector. In this paper we will discuss features about the two technologies and some potential applications for the advanced safeguarding of nuclear materials.

  19. Ultra Wide Band RFID Neutron Tags for Nuclear Materials Monitoring

    International Nuclear Information System (INIS)

    Nekoogar, F.; Dowla, F.; Wang, T.

    2010-01-01

    Recent advancements in the ultra-wide band Radio Frequency Identification (RFID) technology and solid state pillar type neutron detectors have enabled us to move forward in combining both technologies for advanced neutron monitoring. The LLNL RFID tag is totally passive and will operate indefinitely without the need for batteries. The tag is compact, can be directly mounted on metal, and has high performance in dense and cluttered environments. The LLNL coin-sized pillar solid state neutron detector has achieved a thermal neutron detection efficiency of 20% and neutron/gamma discrimination of 1E5. These performance values are comparable to a fieldable 3 He based detector. In this paper we will discuss features about the two technologies and some potential applications for the advanced safeguarding of nuclear materials.

  20. FY2011 Annual Progress Report for Propulsion Materials

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Patrick B. [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States); Schutte, Carol L. [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States); Gibbs, Jerry L. [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

    2011-12-01

    Annual Progress Report for Propulsion Materials focusing on enabling and innovative materials technologies that are critical in improving the efficiency of advanced engines by providing enabling materials support for combustion, hybrid, and power electronics development.

  1. Analysis of compressive failure of layered materials by kink band broadening

    DEFF Research Database (Denmark)

    Jensen, Henrik Myhre

    1999-01-01

    Failure by steady state kink band broadening in uni-directional fibre composites or layered materials is analysed. An incremental scheme for calculation of kink band broadening stresses and lock-up conditions in the band for arbitrary material behaviour is presented. The method is illustrated...... by material data which are representative for polymer matrix composites for which experimental work exists. (C) 1999 Elsevier Science Ltd. All rights reserved....

  2. Materials Department annual progress report for 1993

    International Nuclear Information System (INIS)

    Horsewell, A.; Hansen, N.

    1994-06-01

    Selected activities of the Materials Department at Risoe National Laboratory during 1993 are described. The work is presented in three chapters: Materials Science, Materials Engineering and Materials Technology. A survey is given of the Department's participation in international collaboration and of its activities within education and training. Furthermore, the main figures outlining the funding and expenditure of the Department are given. Lists of staff members, visiting scientists, publications, lectures and poster presentations are included. (au) (220 refs.)

  3. FY2016 Propulsion Materials Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    The Propulsion Materials Program actively supports the energy security and reduction of greenhouse emissions goals of VTO by investigating and identifying the materials properties that are most essential for continued development of cost-effective, highly efficient, and environmentally friendly next-generation heavy and light-duty powertrains. The technical approaches available to enhance propulsion systems focus on improvements in both vehicle efficiency and fuel substitution, both of which must overcome the performance limitations of the materials currently in use. Propulsion Materials Program activities work with national laboratories, industry experts, and VTO powertrain systems (e.g., Advanced Combustion Engines and Fuels) teams to develop strategies that overcome materials limitations in future powertrain performance. The technical maturity of the portfolio of funded projects ranges from basic science to subsystem prototype validation. Projects within a Propulsion Materials Program activity address materials concerns that directly impact critical technology barriers within each of the above programs, including barriers that impact fuel efficiency, thermal management, emissions reduction, improved reliability, and reduced manufacturing costs. The program engages only the barriers that result from material property limitations and represent fundamental, high-risk materials issues.

  4. Progress in advanced high temperature materials technology

    Science.gov (United States)

    Freche, J. C.; Ault, G. M.

    1976-01-01

    Materials for intermediate temperature applications are considered, taking into account possibilities regarding the use of prealloyed powder processing to obtain superalloys with increased strength for turbine disk applications. Materials for high temperature application are also discussed. Attention is given to oxide dispersion strengthened alloys (ODS), ceramics, directionally solidified eutectics, ODS + gamma prime alloys, and composites. A description is presented of various approaches for providing environmental protection.

  5. The progress of nanocrystalline hydride electrode materials

    International Nuclear Information System (INIS)

    Jurczyk, M.

    2004-01-01

    This paper reviews research at the Institute of Materials Science and Engineering, Poznan University of Technology, on the synthesis of nanocrystalline hydride electrode materials. Nanocrystalline materials have been synthesized by mechanical alloying (MA) followed by annealing. Examples of the materials include TiFe - , ZrV 2- , LaNi 5 and Mg 2 Ni-type phases. Details on the process used and the enhancement of properties due to the nanoscale structures are presented. The synthesized alloys were used as negative electrode materials for Ni-MH battery. The properties of hydrogen host materials can be modified substantially by alloying to obtain the desired storage characteristics. For example, it was found that the respective replacement of Fe in TiFe by Ni and/or by Cr, Co, Mo improved not only the discharge capacity but also the cycle life of these electrodes. The hydrogen storage properties of nanocrystalline ZrV 2 - and LaNi 5 -type powders prepared by mechanical alloying and annealing show no big difference with those of melt casting (polycrystalline) alloys. On the other hand, a partial substitution of Mg by Mn or Al in Mg 2 Ni alloy leads to an increase in discharge capacity, at room temperature. Furthermore, the effect of the nickel and graphite coating on the structure of some nanocrystalline alloys and the electrodes characteristics were investigated. In the case of Mg 2 Ni-type alloy mechanical coating with graphite effectively reduced the degradation rate of the studied electrode materials. The combination of a nanocrystalline TiFe - , ZrV 2 - and LaNi 5 -type hydride electrodes and a nickel positive electrode to form a Ni-MH battery, has been successful. (authors)

  6. FY2015 Lightweight Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-09-30

    The Lightweight Materials research and development (R&D) area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing lightweight materials for passenger and commercial vehicles. This report describes the progress made on the research and development projects funded by the Lightweight Materials area.

  7. User-Defined Material Model for Progressive Failure Analysis

    Science.gov (United States)

    Knight, Norman F. Jr.; Reeder, James R. (Technical Monitor)

    2006-01-01

    An overview of different types of composite material system architectures and a brief review of progressive failure material modeling methods used for structural analysis including failure initiation and material degradation are presented. Different failure initiation criteria and material degradation models are described that define progressive failure formulations. These progressive failure formulations are implemented in a user-defined material model (or UMAT) for use with the ABAQUS/Standard1 nonlinear finite element analysis tool. The failure initiation criteria include the maximum stress criteria, maximum strain criteria, the Tsai-Wu failure polynomial, and the Hashin criteria. The material degradation model is based on the ply-discounting approach where the local material constitutive coefficients are degraded. Applications and extensions of the progressive failure analysis material model address two-dimensional plate and shell finite elements and three-dimensional solid finite elements. Implementation details and use of the UMAT subroutine are described in the present paper. Parametric studies for composite structures are discussed to illustrate the features of the progressive failure modeling methods that have been implemented.

  8. Progress report, Chemistry and Materials Division

    International Nuclear Information System (INIS)

    1981-05-01

    Laser radiation has been used to anneal damage created by implantation of arsenic ions into silicon single-crystal wafers. The threshold for recovery of lattice order, as measured by ion channeling methods, appeared at an energy density of 1.2 J.cm -2 . Deuterium-enriched water has been recovered for the first time in visible amounts from a process based on laser photolysis. High performance liquid chromatography has been applied to the determination of U(VI) in ground water and urine. Results with low ground water concentrations were judged to be successful, while only limited success was achieved with urine. The first analyses in support of the production of (Th,Pu)O 2 fuel elements were completed successfully. Experiments performed during the quarter have shown that cracking of Zr-2.5 percent Nb alloy by gaseous hydrogen is inhibited by traces of oxygen. It was found that there was no inhibition by helium in the absence of trace oxygen. Excellent agreement has been obtained between the growth and creep constants derived from ion-irradiated cantilever beam specimens and those from reactor irradiation of the same materials. (O.T.)

  9. 3D Progressive Damage Modeling for Laminated Composite Based on Crack Band Theory and Continuum Damage Mechanics

    Science.gov (United States)

    Wang, John T.; Pineda, Evan J.; Ranatunga, Vipul; Smeltzer, Stanley S.

    2015-01-01

    A simple continuum damage mechanics (CDM) based 3D progressive damage analysis (PDA) tool for laminated composites was developed and implemented as a user defined material subroutine to link with a commercially available explicit finite element code. This PDA tool uses linear lamina properties from standard tests, predicts damage initiation with an easy-to-implement Hashin-Rotem failure criteria, and in the damage evolution phase, evaluates the degradation of material properties based on the crack band theory and traction-separation cohesive laws. It follows Matzenmiller et al.'s formulation to incorporate the degrading material properties into the damaged stiffness matrix. Since nonlinear shear and matrix stress-strain relations are not implemented, correction factors are used for slowing the reduction of the damaged shear stiffness terms to reflect the effect of these nonlinearities on the laminate strength predictions. This CDM based PDA tool is implemented as a user defined material (VUMAT) to link with the Abaqus/Explicit code. Strength predictions obtained, using this VUMAT, are correlated with test data for a set of notched specimens under tension and compression loads.

  10. Progressive failure analysis of fibrous composite materials and structures

    Science.gov (United States)

    Bahei-El-din, Yehia A.

    1990-01-01

    A brief description is given of the modifications implemented in the PAFAC finite element program for the simulation of progressive failure in fibrous composite materials and structures. Details of the memory allocation, input data, and the new subroutines are given. Also, built-in failure criteria for homogeneous and fibrous composite materials are described.

  11. Engineering intermediate-band photovoltaic material by heavily co-doping selenium and nitrogen in silicon

    Science.gov (United States)

    Dong, Xiao; Wang, Yongyong; Song, Xiaohui

    2018-01-01

    Among the various dimer configurations, the substitutional dimer exhibits the lowest formation energy and can form an impurity band that overlaps with the conduction band. The impurity band turns into an isolated and partially filled intermediate-band in the bandgap when the two impurity atoms are separated from a dimer to the remotest distance. The configurations with different impurity atom distances are stable in the Si material owing to their constant formation energy and can lead to a significant enhancement of the optical absorption in the infrared wavelength range.

  12. Recent Progress in Advanced Materials for Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Jiajun Chen

    2013-01-01

    Full Text Available The development and commercialization of lithium ion batteries is rooted in material discovery. Promising new materials with high energy density are required for achieving the goal toward alternative forms of transportation. Over the past decade, significant progress and effort has been made in developing the new generation of Li-ion battery materials. In the review, I will focus on the recent advance of tin- and silicon-based anode materials. Additionally, new polyoxyanion cathodes, such as phosphates and silicates as cathode materials, will also be discussed.

  13. Band inversion mechanism in topological insulators: A guideline for materials design

    KAUST Repository

    Zhu, Zhiyong

    2012-06-01

    Alteration of the topological order by band inversion is a key ingredient of a topologically nontrivial material. Using first-principles calculations for HgTe, PtScBi, and Bi2Se3, we argue that it is not accurate to ascribe the band inversion to the spin-orbit coupling. Instead, scalar relativistic effects and/or lattice distortions are found to be essential. Therefore, the search for topologically nontrivial materials should focus on band shifts due to these mechanisms rather than spin-orbit coupling. We propose an effective scheme to search for new topological insulators.

  14. Adiabatic Shear Bands in Simple and Dipolar Viscoplastic Materials

    Science.gov (United States)

    1991-08-01

    Slock ’Jncergoing overall Simple Shearing Deformations. 4. PUBLICATIONS a) ARTICLES IN REFEREED JOURNALS 1. R. C. Batra and Y. W. Kwon ...11) (12) wmen can be viewed as a generalized von Mises yield surface when the flow stress (given oy the ngnt-hand side of (12)) at a material...since Vtarchand and Duffy observed that during the drop o( the shear stress, the nominal strain increases oy approximately 5%. The Litonski law for

  15. Shear banding and its contribution to texture evolution in rotated Goss orientations of BCC structured materials

    NARCIS (Netherlands)

    Nguyen-MInh, T.; Sidor, J.J.; Petrov, R.H.; Kestens, L.A.I.

    2015-01-01

    Due to progressive deformation, the dislocation densities in crystals are accumulated and the resistance of grains to further deformation increases. Homogeneous deformation becomes energetically less favorable, which may result for some orientations in strain localization. In-grain shear banding, a

  16. Progress in advanced high temperature turbine materials, coatings, and technology

    Science.gov (United States)

    Freche, J. C.; Ault, G. M.

    1978-01-01

    Advanced materials, coatings, and cooling technology is assessed in terms of improved aircraft turbine engine performance. High cycle operating temperatures, lighter structural components, and adequate resistance to the various environmental factors associated with aircraft gas turbine engines are among the factors considered. Emphasis is placed on progress in development of high temperature materials for coating protection against oxidation, hot corrosion and erosion, and in turbine cooling technology. Specific topics discussed include metal matrix composites, superalloys, directionally solidified eutectics, and ceramics.

  17. Advanced electron microscopy of wide band-gap semiconductor materials

    International Nuclear Information System (INIS)

    Fay, M.W.

    2000-10-01

    The microstructure of GaN layers grown by metal organic vapour phase epitaxy on (0001) sapphire substrates using a novel precursor for deposition of AlN buffer layers has been investigated and compared to layers grown using low temperature GaN buffer layers and state-of-the-art material. It has been shown that the quality of layers grown using the novel precursor is comparable to the state-of-the-art material. TEM analysis has been performed of multiple quantum wells of InGaN grown within GaN epitaxial layers by metal organic vapour phase epitaxy. Elementally sensitive TEM techniques have been used to determine the spatial distribution of In and Ga within these structures. Fluctuations in In sensitive images are observed on the nm-scale. Clear evidence of segregation of In during layer growth has been seen. Models of the In segregation are in good agreement with experimental results. Elementally sensitive techniques have been used to investigate the elemental distributions in TiAl and NiAu contacts to GaN. Annealing of TiAl contacts has been seen to result in the formation of a thin interfacial Ti rich phase, and of N depletion at the surface of the GaN layer to the depth of tens of nm. Annealing NiAu contacts at 700 deg. C was seen to result in the formation of Ga-rich interfacial phases, of both crystalline and amorphous structure. ZnS and ZnCdS layers grown on (001) GaP supplied by the University of Hull have been investigated. ZnS layers were found to contain a high density of inclined stacking faults throughout the layer, originating from the interface with the substrate. Energy sensitive techniques have been used to investigate ZnCdS quantum well structures. The use of a ZnCdS superlattice structure around a ZnCdS quantum well to approximate a reduced barrier was seen to result in less thickness variations than when no barrier was used. (author)

  18. [Progress on classification and application of artificial hip joint materials].

    Science.gov (United States)

    Wu, Xiao; He, Ben-xiang; Tan, Ya-jun

    2016-03-01

    The selection of the prosthetic material determine the success or failure of hip arthroplasty. Currently, the metals, ceramics, polymer composites and carbon materials are the main prosthetic materials of artificial hip joint. They have some progresses in biocompatibility, elastic modulus,mechanical properties, useful life, but they still can't reach the ideal standard of design. In this essay, we mainly review the characteristics and applications of the current artificial hip joint materials through its classification in order to provide a reference for choosing appropriate hip joint materials in clinic and increasing characteristic of materials. We consider the polymer composites has more advantages such as biocompatibility, mechanical properties, corrosion resistance and price, even if it has shortages in abrasion resistance. As the researches of polymer composites are main focus on abrasion resistance, articular surface and strength,and its performances are increased fast, it has a wide prospect in future.

  19. Plant materials program. Progress report, June 1980-May 1981

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.; McIlree, A.

    1981-11-01

    This is the first annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have a high impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, and steam generator tube denting and cracking. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic areas: intergranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  20. Plant Materials Program: progress June 1981 to May 1982

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.

    1983-02-01

    This is the second annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have a high impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, steam geerator tube attack and cracking, and cracking of nickel alloy springs, beams and pins. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic areas: intergranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  1. Plant Materials Program: progress June 1981-May 1982

    International Nuclear Information System (INIS)

    Childs, W.; Cubicciotti, D.; Fox, M.; Giannuzzi, A.; Gilman, J.; Jones, R.

    1983-02-01

    This is the second annual progress report of the Plant Materials Subprogram, which was organized in May 1980 to address corrosion-related materials problems in light water reactors. The first section of the report provides an overview of plant materials problems which have impact on plant availability. These include pipe and pressure vessel cracking, condenser leakage, turbine disc cracking, steam generator tube attack and cracking, and cracking of nickel alloy springs, beams and pins. The status and goals of research and development work related to each of these problems are reviewed briefly. Subsequent report sections provide more detailed reviews of significant progress in the relevant technical topic area: integranular stress corrosion cracking of austenitic stainless steels; environmentally-assisted cracking of carbon and low alloy steels; intergranular stress corrosion cracking of nickel-base alloys; and improved fabrication technology

  2. Progress in GaAs Metamorphic HEMT Technology for Microwave Applications. High Efficiency Ka-Band MHEMT Power MMICs

    Science.gov (United States)

    Smith, P. M.; Dugas, D.; Chu, K.; Nichols, K.; Duh, K. H.; Fisher, J.; MtPleasant, L.; Xu, D.; Gunter, L.; Vera, A.

    2003-01-01

    This paper reviews recent progress in the development of GaAs metamorphic HEMT (MHEMT) technology for microwave applications. Commercialization has begun, while efforts to further improve performance, manufacturability and reliability continue. We also report the first multi-watt MHEMT MMIC power amplifiers, demonstrating up to 3.2W output power and record power-added efficiency (PAE) at Ka-band.

  3. Recent progress in chiral photonic band-gap liquid crystals for laser applications.

    Science.gov (United States)

    Furumi, Seiichi

    2010-12-01

    This article describes a brief review of recent research advances in chiral liquid crystals (CLCs) for laser applications. The CLC molecules have an intrinsic capability to spontaneously organize supramolecular helical assemblages consisting of liquid crystalline layers through their helical twisting power. Such CLC supramolecular helical structures can be regarded as one-dimensional photonic crystals (PhCs). Owing to their supramolecular helical structures, the CLCs show negative birefringence along the helical axis. Selective reflection of circularly polarized light is the most unique and important optical property in order to generate internal distributed feedback effect for optically-excited laser emission. When a fluorescent dye is embedded in the CLC medium, optical excitation gives rise to stimulated laser emission peak(s) at the band edge(s) and/or within the CLC selective reflection. Furthermore, the optically-excited laser emission peaks can be controlled by external stimuli through the self-organization of CLC molecules. This review introduces the research background of CLCs carried out on the PhC realm, and highlights intriguing precedents of various CLC materials for laser applications. It would be greatly advantageous to fabricate active CLC laser devices by controlling the supramolecular helical structures. Taking account of the peculiar features, we can envisage that a wide variety of supramolecular helical structures of CLC materials will play leading roles in next-generation optoelectronic molecular devices. Copyright © 2010 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.

  4. 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.

  5. Theoretical modelling of intermediate band solar cell materials based on metal-doped chalcopyrite compounds

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, P. [Instituto de Energia Solar and Dpt. de Tecnologias Especiales, ETSI de Telecomunicacion, UPM, Ciudad Universitaria s/n, 28040 Madrid (Spain)]. E-mail: pablop@etsit.upm.es; Sanchez, K. [Instituto de Energia Solar and Dpt. de Tecnologias Especiales, ETSI de Telecomunicacion, UPM, Ciudad Universitaria s/n, 28040 Madrid (Spain); Conesa, J.C. [Instituto de Catalisis y Petroleoquimica, CSIC, Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Fernandez, J.J. [Dpt. de Fisica Fundamental, Universidad Nacional de Educacion a Distancia, 28080, Madrid (Spain); Wahnon, P. [Instituto de Energia Solar and Dpt. de Tecnologias Especiales, ETSI de Telecomunicacion, UPM, Ciudad Universitaria s/n, 28040 Madrid (Spain)

    2007-05-31

    Electronic structure calculations are carried out for CuGaS{sub 2} partially substituted with Ti, V, Cr or Mn to ascertain if some of these systems could provide an intermediate band material able to give a high efficiency photovoltaic cell. Trends in electronic level positions are analyzed and more accurate advanced theory levels (exact exchange or Hubbard-type methods) are used in some cases. The Ti-substituted system seems more likely to yield an intermediate band material with the desired properties, and furthermore seems realizable from the thermodynamic point of view, while those with Cr and Mn might give half-metal structures with applications in spintronics.

  6. Band Gap Tuning via Lattice Contraction and Octahedral Tilting in Perovskite Materials for Photovoltaics

    International Nuclear Information System (INIS)

    Prasanna, Rohit; Gold-Parker, Aryeh; Leijtens, Tomas; Conings, Bert

    2017-01-01

    Tin and lead iodide perovskite semiconductors of the composition AMX_3, where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of 3D metal halide perovskites. Using a smaller A-site cation can distort the perovskite lattice in two distinct ways: by tilting the MX_6 octahedra or by simply contracting the lattice isotropically. The former effect tends to raise the band gap, while the latter tends to decrease it. Lead iodide perovskites show an increase in band gap upon partial substitution of the larger formamidinium with the smaller cesium, due to octahedral tilting. Perovskites based on tin, which is slightly smaller than lead, show the opposite trend: they show no octahedral tilting upon Cs-substitution but only a contraction of the lattice, leading to progressive reduction of the band gap. We outline a strategy to systematically tune the band gap and valence and conduction band positions of metal halide perovskites through control of the cation composition. Using this strategy, we demonstrate solar cells that harvest light in the infrared up to 1040 nm, reaching a stabilized power conversion efficiency of 17.8%, showing promise for improvements of the bottom cell of all-perovskite tandem solar cells. In conclusion, the mechanisms of cation-based band gap tuning we describe are broadly applicable to 3D metal halide perovskites and will be useful in further development of perovskite semiconductors for optoelectronic applications.

  7. Band Gap Tuning via Lattice Contraction and Octahedral Tilting in Perovskite Materials for Photovoltaics.

    Science.gov (United States)

    Prasanna, Rohit; Gold-Parker, Aryeh; Leijtens, Tomas; Conings, Bert; Babayigit, Aslihan; Boyen, Hans-Gerd; Toney, Michael F; McGehee, Michael D

    2017-08-16

    Tin and lead iodide perovskite semiconductors of the composition AMX 3 , where M is a metal and X is a halide, are leading candidates for high efficiency low cost tandem photovoltaics, in part because they have band gaps that can be tuned over a wide range by compositional substitution. We experimentally identify two competing mechanisms through which the A-site cation influences the band gap of 3D metal halide perovskites. Using a smaller A-site cation can distort the perovskite lattice in two distinct ways: by tilting the MX 6 octahedra or by simply contracting the lattice isotropically. The former effect tends to raise the band gap, while the latter tends to decrease it. Lead iodide perovskites show an increase in band gap upon partial substitution of the larger formamidinium with the smaller cesium, due to octahedral tilting. Perovskites based on tin, which is slightly smaller than lead, show the opposite trend: they show no octahedral tilting upon Cs-substitution but only a contraction of the lattice, leading to progressive reduction of the band gap. We outline a strategy to systematically tune the band gap and valence and conduction band positions of metal halide perovskites through control of the cation composition. Using this strategy, we demonstrate solar cells that harvest light in the infrared up to 1040 nm, reaching a stabilized power conversion efficiency of 17.8%, showing promise for improvements of the bottom cell of all-perovskite tandem solar cells. The mechanisms of cation-based band gap tuning we describe are broadly applicable to 3D metal halide perovskites and will be useful in further development of perovskite semiconductors for optoelectronic applications.

  8. Experimental method for the evaluation of the susceptibility of materials to shear band formation

    Directory of Open Access Journals (Sweden)

    Tham R.

    2012-08-01

    Full Text Available In order to characterize materials with respect to their susceptibility to shear band formation at high strain rates, a modified Hopkinson pressure bar apparatus and hat-shaped steel specimens with a shear zone having a width significantly larger than the typical width of adiabatic bands are used. The sample is directly impacted by the striker. The force acting on the sample is measured with a PVDF-gauge between the sample and the output bar. The displacement is recorded with an electro-optical extensometer. The energy absorbed by the shearing process up to failure can be used as a reference for the susceptibility of materials to shear band formation. The method is demonstrated comparing the shear behavior of two high-strength steels with similar metallic structure and strength. Differences were found in the transition region between quasi-static and fully adiabatic shearing conditions where the energy up to rupture differs by 40 %. For fully adiabatic shear band formation, the deformation process of both materials equals. At extreme rates, shear processes are mainly governed by the thermodynamic properties of the materials. On the other hand, strength and structural properties play a role for low and intermediate rates where global and localized shear mechanisms occur in parallel.

  9. Uncertainty relations and topological-band insulator transitions in 2D gapped Dirac materials.

    Science.gov (United States)

    Romera, E; Calixto, M

    2015-05-08

    Uncertainty relations are studied for a characterization of topological-band insulator transitions in 2D gapped Dirac materials isostructural with graphene. We show that the relative or Kullback-Leibler entropy in position and momentum spaces, and the standard variance-based uncertainty relation give sharp signatures of topological phase transitions in these systems.

  10. Laser-induced optical breakdown spectroscopy of polymer materials based on evaluation of molecular emission bands

    Science.gov (United States)

    Trautner, Stefan; Jasik, Juraj; Parigger, Christian G.; Pedarnig, Johannes D.; Spendelhofer, Wolfgang; Lackner, Johannes; Veis, Pavel; Heitz, Johannes

    2017-03-01

    Laser-induced breakdown spectroscopy (LIBS) for composition analysis of polymer materials results in optical spectra containing atomic and ionic emission lines as well as molecular emission bands. In the present work, the molecular bands are analyzed to obtain spectroscopic information about the plasma state in an effort to quantify the content of different elements in the polymers. Polyethylene (PE) and a rubber material from tire production are investigated employing 157 nm F2 laser and 532 nm Nd:YAG laser ablation in nitrogen and argon gas background or in air. The optical detection reaches from ultraviolet (UV) over the visible (VIS) to the near infrared (NIR) spectral range. In the UV/VIS range, intense molecular emissions, C2 Swan and CN violet bands, are measured with an Echelle spectrometer equipped with an intensified CCD camera. The measured molecular emission spectra can be fitted by vibrational-rotational transitions by open access programs and data sets with good agreement between measured and fitted spectra. The fits allow determining vibrational-rotational temperatures. A comparison to electronic temperatures Te derived earlier from atomic carbon vacuum-UV (VUV) emission lines show differences, which can be related to different locations of the atomic and molecular species in the expanding plasma plume. In the NIR spectral region, we also observe the CN red bands with a conventional CDD Czerny Turner spectrometer. The emission of the three strong atomic sulfur lines between 920 and 925 nm is overlapped by these bands. Fitting of the CN red bands allows a separation of both spectral contributions. This makes a quantitative evaluation of sulfur contents in the start material in the order of 1 wt% feasible.

  11. Thermochromic Luminescent Materials and Multi-Emission Bands in d10Clusters.

    Science.gov (United States)

    Gautier, Romain; Latouche, Camille; Paris, Michael; Massuyeau, Florian

    2017-03-30

    Thermochromic luminescent compounds with d 10 metal ions are interesting materials for applications such as sensors or display devices. However, these properties are difficult to predict prior to their synthesis. In this communication, we investigated materials with structural assemblies known to be responsible of distinct luminescence mechanisms and show that they can be interesting potential thermometers. Thus, we compared the synthesis of a zinc halide and a copper halide based compounds which only differ in their ability to create clusters with metallophilic interactions. The compounds synthesized by hydrothermal method have been structurally characterized by Single-crystal X-ray diffraction, Solid-State NMR, FTIR, UV-Visible spectroscopy, thermal analysis and EPR. The photoluminescence properties of the two materials have been characterized at different temperatures. The copper bromide compound shows luminescence thermochromism in a wide spectrum of colors owing to the formation of clusters generating multi-emission bands while the zinc bromide exhibits a single emission band and no thermochromism.

  12. Antimicrobial graphene family materials: Progress, advances, hopes and fears.

    Science.gov (United States)

    Lukowiak, Anna; Kedziora, Anna; Strek, Wieslaw

    2016-10-01

    Graphene-based materials have become very popular bionanotechnological instruments in the last few years. Since 2010, the graphene family materials have been recognized as worthy of attention due to its antimicrobial properties. Functionalization of graphene (or rather graphene oxide) surface creates the possibilities to obtain efficient antimicrobial agents. In this review, progress and advances in this field in the last few years are described and discussed. Special attention is devoted to materials based on graphene oxide in which specifically selected components significantly modify biological activity of this carbon structure. Short introduction concerns the physicochemical properties of the graphene family materials. In the section on antimicrobial properties, proposed mechanisms of activity against microorganisms are given showing enhanced action of nanocomposites also under light irradiation (photoinduced activity). Another important feature, i.e. toxicity against eukaryotic cells, is presented with up-to-date data. Taking into account all the information on the properties of the described materials and usefulness of the graphene family as antimicrobial agents, hopes and fears concerning their application are discussed. Finally, some examples of promising usage in medicine and other fields, e.g. in phytobiology and water remediation, are shown. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Antiferroelectric Materials, Applications and Recent Progress on Multiferroic Heterostructures

    Science.gov (United States)

    Zhou, Ziyao; Yang, Qu; Liu, Ming; Zhang, Zhiguo; Zhang, Xinyang; Sun, Dazhi; Nan, Tianxiang; Sun, Nianxiang; Chen, Xing

    2015-04-01

    Antiferroelectric (AFE) materials with adjacent dipoles oriented in antiparallel directions have a double polarization hysteresis loops. An electric field (E-field)-induced AFE-ferroelectric (FE) phase transition takes place in such materials, leading to a large lattice strain and energy change. The high dielectric constant and the distinct phase transition in AFE materials provide great opportunities for the realization of energy storage devices like super-capacitors and energy conversion devices such as AFE MEMS applications. Lots of work has been done in this field since 60-70 s. Recently, the strain tuning of the spin, charge and orbital orderings and their interactions in complex oxides and multiferroic heterostructures have received great attention. In these systems, a single control parameter of lattice strain is used to control lattice-spin, lattice-phonon, and lattice-charge interactions and tailor properties or create a transition between distinct magnetic/electronic phases. Due to the large strain/stress arising from the phase transition, AFE materials are great candidates for integrating with ferromagnetic (FM) materials to realize in situ manipulation of magnetism and lattice-ordered parameters by voltage. In this paper, we introduce the AFE material and it's applications shortly and then review the recent progress in AFEs based on multiferroic heterostructures. These new multiferroic materials could pave a new way towards next generation light, compact, fast and energy efficient voltage tunable RF/microwave, spintronic and memory devices promising approaches to in situ manipulation of lattice-coupled order parameters is to grow epitaxial oxide films on FE/ferroelastic substrates.

  14. Structural analysis, electronic properties, and band gaps of a graphene nanoribbon: A new 2D materials

    Science.gov (United States)

    Dass, Devi

    2018-03-01

    Graphene nanoribbon (GNR), a new 2D carbon nanomaterial, has some unique features and special properties that offer a great potential for interconnect, nanoelectronic devices, optoelectronics, and nanophotonics. This paper reports the structural analysis, electronic properties, and band gaps of a GNR considering different chirality combinations obtained using the pz orbital tight binding model. In structural analysis, the analytical expressions for GNRs have been developed and verified using the simulation for the first time. It has been found that the total number of unit cells and carbon atoms within an overall unit cell and molecular structure of a GNR have been changed with the change in their chirality values which are similar to the values calculated using the developed analytical expressions thus validating both the simulation as well as analytical results. Further, the electronic band structures at different chirality values have been shown for the identification of metallic and semiconductor properties of a GNR. It has been concluded that all zigzag edge GNRs are metallic with very small band gaps range whereas all armchair GNRs show both the metallic and semiconductor nature with very small and high band gaps range. Again, the total number of subbands in each electronic band structure is equal to the total number of carbon atoms present in overall unit cell of the corresponding GNR. The semiconductors GNRs can be used as a channel material in field effect transistor suitable for advanced CMOS technology whereas the metallic GNRs could be used for interconnect.

  15. Progress and Strategies for Testing of Materials for Solar Panels

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Sarah

    2017-04-25

    Accelerated testing is key to confident launch of a new product. However, for new products like solar panels, the best approach is not always clear. The challenge for materials manufacturers is that test times can be long. Also, small-coupon testing may not predict the behavior in the full-size module, but testing of the full-size module is too expensive. As a result, solar panel test standards like IEC 61215 are useful, but are not sufficient. Material manufacturers have needed to define their own test protocols. This presentation will review some historical data (e.g., data show that manufacturers are making great progress toward reducing encapsulant discoloration) and describe advances in material testing (for example, new techniques are being demonstrated on how to more quantitatively assess adhesion, detect tendency for delamination, and understand how encapsulant properties affect other properties like cracking of cells). The International PV Quality Assurance Task Force has been researching climate-specific weathering tests toward the goal of defining international standards that would simplify qualification and quality assurance testing for materials. The status of these tests and the strategies for how to organize these standards to best meet the needs of the industry will be discussed.

  16. Band structures tunability of bulk 2D phononic crystals made of magneto-elastic materials

    Directory of Open Access Journals (Sweden)

    J. O. Vasseur

    2011-12-01

    Full Text Available The feasibility of contactless tunability of the band structure of two-dimensional phononic crystals is demonstrated by employing magnetostrictive materials and applying an external magnetic field. The influence of the amplitude and of the orientation with respect to the inclusion axis of the applied magnetic field are studied in details. Applications to tunable selective frequency filters with switching functionnality and to reconfigurable wave-guides and demultiplexing devices are then discussed.

  17. Chemical synthesis of Cd-free wide band gap materials for solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Sankapal, B.R.; Sartale, S.D.; Ennaoui, A. [Hahn-Meitner-Institut, Berlin (Germany). Department of Solar Energy Research; Lokhande, C.D. [Shivaji University, Kolhapur (India). Department of Physics

    2004-07-01

    Chemical methods are nowadays very attractive, since they are relatively simple, low cost and convenient for larger area deposition of thin films. In this paper, we outline our work related to the synthesis and characterization of some wide band gap semiconducting material thin films prepared by using solution methods, namely, chemical bath deposition and successive ionic layer adsorption and reaction (SILAR). The optimum preparative parameters are given and respective structural, surface morphological, compositional, optical, and electrical properties are described. Some materials we used in solar cells as buffer layers and achieved remarkable results, which are summarized. (author)

  18. Liquid-crystal photonic-band-gap materials the tunable electromagnetic vacuum

    CERN Document Server

    Busch, K

    1999-01-01

    We demonstrate that when an optically birefringent nematic liquid crystal is infiltrated into the void regions of an inverse opal, photonic-band-gap (PBG) material, the resulting composite material exhibits a completely tunable PBG. $9 In particular, the three- dimensional PBG can be completely opened or closed by applying an electric field which rotates the axis of the nematic molecules relative to the inverse opal backbone. Tunable light localization effects may $9 be realized by controlling the orientational disorder in the nematic. (28 refs).

  19. Composite Beam Theory with Material Nonlinearities and Progressive Damage

    Science.gov (United States)

    Jiang, Fang

    Beam has historically found its broad applications. Nowadays, many engineering constructions still rely on this type of structure which could be made of anisotropic and heterogeneous materials. These applications motivate the development of beam theory in which the impact of material nonlinearities and damage on the global constitutive behavior has been a focus in recent years. Reliable predictions of these nonlinear beam responses depend on not only the quality of the material description but also a comprehensively generalized multiscale methodology which fills the theoretical gaps between the scales in an efficient yet high-fidelity manner. The conventional beam modeling methodologies which are built upon ad hoc assumptions are in lack of such reliability in need. Therefore, the focus of this dissertation is to create a reliable yet efficient method and the corresponding tool for composite beam modeling. A nonlinear beam theory is developed based on the Mechanics of Structure Genome (MSG) using the variational asymptotic method (VAM). The three-dimensional (3D) nonlinear continuum problem is rigorously reduced to a one-dimensional (1D) beam model and a two-dimensional (2D) cross-sectional analysis featuring both geometric and material nonlinearities by exploiting the small geometric parameter which is an inherent geometric characteristic of the beam. The 2D nonlinear cross-sectional analysis utilizes the 3D material models to homogenize the beam cross-sectional constitutive responses considering the nonlinear elasticity and progressive damage. The results from such a homogenization are inputs as constitutive laws into the global nonlinear 1D beam analysis. The theoretical foundation is formulated without unnecessary kinematic assumptions. Curvilinear coordinates and vector calculus are utilized to build the 3D deformation gradient tensor, of which the components are formulated in terms of cross-sectional coordinates, generalized beam strains, unknown warping

  20. Fe/Co doped molybdenum diselenide: a promising two-dimensional intermediate-band photovoltaic material

    International Nuclear Information System (INIS)

    Zhang, Jiajia; He, Haiyan; Pan, Bicai

    2015-01-01

    An intermediate-band (IB) photovoltaic material is an important candidate in developing the new-generation solar cell. In this paper, we propose that the Fe-doped or the Co-doped MoSe 2 just meets the required features in IB photovoltaic materials. Our calculations demonstrate that when the concentration of the doped element reaches 11.11%, the doped MoSe 2 shows a high absorptivity for both infrared and visible light, where the photovoltaic efficiency of the doped MoSe 2 is as high as 56%, approaching the upper limit of photovoltaic efficiency of IB materials. So, the Fe- or Co-doped MoSe 2 is a promising two-dimensional photovoltaic material. (paper)

  1. Wave propagation in ordered, disordered, and nonlinear photonic band gap materials

    Energy Technology Data Exchange (ETDEWEB)

    Lidorikis, Elefterios [Iowa State Univ., Ames, IA (United States)

    1999-12-10

    Photonic band gap materials are artificial dielectric structures that give the promise of molding and controlling the flow of optical light the same way semiconductors mold and control the electric current flow. In this dissertation the author studied two areas of photonic band gap materials. The first area is focused on the properties of one-dimensional PBG materials doped with Kerr-type nonlinear material, while, the second area is focused on the mechanisms responsible for the gap formation as well as other properties of two-dimensional PBG materials. He first studied, in Chapter 2, the general adequacy of an approximate structure model in which the nonlinearity is assumed to be concentrated in equally-spaced very thin layers, or 6-functions, while the rest of the space is linear. This model had been used before, but its range of validity and the physical reasons for its limitations were not quite clear yet. He performed an extensive examination of many aspects of the model's nonlinear response and comparison against more realistic models with finite-width nonlinear layers, and found that the d-function model is quite adequate, capturing the essential features in the transmission characteristics. The author found one exception, coming from the deficiency of processing a rigid bottom band edge, i.e. the upper edge of the gaps is always independent of the refraction index contrast. This causes the model to miss-predict that there are no soliton solutions for a positive Kerr-coefficient, something known to be untrue.

  2. Controllable Absorption and Dispersion Properties of an RF-driven Five-Level Atom in a Double-Band Photonic-Band-Gap Material

    International Nuclear Information System (INIS)

    Ding Chunling; Li Jiahua; Yang Xiaoxue

    2011-01-01

    The probe absorption-dispersion spectra of a radio-frequency (RF)-driven five-level atom embedded in a photonic crystal are investigated by considering the isotropic double-band photonic-band-gap (PBG) reservoir. In the model used, the two transitions are, respectively, coupled by the upper and lower bands in such a PBG material, thus leading to some curious phenomena. Numerical simulations are performed for the optical spectra. It is found that when one transition frequency is inside the band gap and the other is outside the gap, there emerge three peaks in the absorption spectra. However, for the case that two transition frequencies lie inside or outside the band gap, the spectra display four absorption profiles. Especially, there appear two sharp peaks in the spectra when both transition frequencies exist inside the band gap. The influences of the intensity and frequency of the RF-driven field on the absorptive and dispersive response are analyzed under different band-edge positions. It is found that a transparency window appears in the absorption spectra and is accompanied by a very steep variation of the dispersion profile by adjusting system parameters. These results show that the absorption-dispersion properties of the system depend strongly on the RF-induced quantum interference and the density of states (DOS) of the PBG reservoir. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  3. Omnidirectional Photonic Band Gap Using Low Refractive Index Contrast Materials and its Application in Optical Waveguides

    KAUST Repository

    Vidal Faez, Angelo

    2012-07-01

    Researchers have argued for many years that one of the conditions for omnidirectional reflection in a one-dimensional photonic crystal is a strong refractive index contrast between the two constituent dielectric materials. Using numerical simulations and the theory of Anderson localization of light, in this work we demonstrate that an omnidirectional band gap can indeed be created utilizing low refractive index contrast materials when they are arranged in a disordered manner. Moreover, the size of the omnidirectional band gap becomes a controllable parameter, which now depends on the number of layers and not only on the refractive index contrast of the system, as it is widely accepted. This achievement constitutes a major breakthrough in the field since it allows for the development of cheaper and more efficient technologies. Of particular interest is the case of high index contrast one-dimensional photonic crystal fibers, where the propagation losses are mainly due to increased optical scattering from sidewall roughness at the interfaces of high index contrast materials. By using low index contrast materials these losses can be reduced dramatically, while maintaining the confinement capability of the waveguide. This is just one of many applications that could be proven useful for this discovery.

  4. Progress on mechanics of carbon nanotubes and derived materials.

    Science.gov (United States)

    Salvetat, Jean-Paul; Bhattacharyya, Sanjib; Pipes, R Byron

    2006-07-01

    This review focuses on the most recent progress in understanding mechanical properties of individual carbon nanotubes (CNT), carbon nanotube arrays, random networks, and polymer matrix composites. The key factors that influence the mechanical properties of these new (nano)materials are identified and discussed. The critical issue appears to be the load transfer efficiency; between nanotubes when organized in bundles, ropes, and networks; between matrix and nanotubes in composites. Among the different paths used to increase load transfer, cross-linking by irradiation is emphasized. A particular attention is paid on the role of nanotubes as nucleating agents in polymer composites, initiating the formation of a crystalline polymer sheath that has important consequence on the mechanical properties. The reinforcing element to be considered in that case is not CNT alone but CNT covered with a cylinder of crystalline polymer. Whereas a lot of effort has been focused on the problem of dispersion, it appears that the problem of nanotube-matrix interphase is almost as important. Recent works show that appropriate surface functionalization can be used both to improve dispersion and tailor the interphase. Nanotube surface engineering combined with methods producing oriented nanocomposites should bring exceptional materials in the near future.

  5. 2-mm Band and X-band electron spin resonance and electron spin-echo investigations of some carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    Tsvetkov, Y.D.; Dzuba, S.A.; Gulin, V.I. [Institute of Chemical Kinetics and Combustion, Novosibirsk (Russian Federation)

    1993-12-31

    Argonne Premium coal samples were studied by using 2-mm band and X-band continuous-wave electron spin resonance (CW ESR) and X-band electron spin-echo (ESE) spectroscopy. The line widths and g factors (Lande g factor, spectroscopic splitting factor) were determined. The correlation between {Delta}g = g{sub {parallel}} - g{sub {perpendicular}} and the carbon content in coal samples was established. Paramagnetic centers in coals could be attributed to radicals with partial redistribution of spin density from polycyclic {pi}-system to peroxide-type structures. The degree of this redistribution depends on the degree of carbonization. Phase relaxation times, T{sub 2}, for these coals were determined by using ESE spectroscopy. 5 refs., 2 figs., 3 tabs.

  6. Wide band design on the scaled absorbing material filled with flaky CIPs

    Science.gov (United States)

    Xu, Yonggang; Yuan, Liming; Gao, Wei; Wang, Xiaobing; Liang, Zichang; Liao, Yi

    2018-02-01

    The scaled target measurement is an important method to get the target characteristic. Radar absorbing materials are widely used in the low detectable target, considering the absorbing material frequency dispersion characteristics, it makes designing and manufacturing scaled radar absorbing materials on the scaled target very difficult. This paper proposed a wide band design method on the scaled absorbing material of the thin absorption coating with added carbonyl iron particles. According to the theoretical radar cross section (RCS) of the plate, the reflection loss determined by the permittivity and permeability was chosen as the main design factor. Then, the parameters of the scaled absorbing materials were designed using the effective medium theory, and the scaled absorbing material was constructed. Finally, the full-size coating plate and scaled coating plates (under three different scale factors) were simulated; the RCSs of the coating plates were numerically calculated and measured at 4 GHz and a scale factor of 2. The results showed that the compensated RCS of the scaled coating plate was close to that of the full-size coating plate, that is, the mean deviation was less than 0.5 dB, and the design method for the scaled material was very effective.

  7. Calculating the optical properties of defects and surfaces in wide band gap materials

    Science.gov (United States)

    Deák, Peter

    2018-04-01

    The optical properties of a material critically depend on its defects, and understanding that requires substantial and accurate input from theory. This paper describes recent developments in the electronic structure theory of defects in wide band gap materials, where the standard local or semi-local approximations of density functional theory fail. The success of the HSE06 screened hybrid functional is analyzed in case of Group-IV semiconductors and TiO2, and shown that it is the consequence of error compensation between semi-local and non-local exchange, resulting in a proper derivative discontinuity (reproduction of the band gap) and a total energy which is a linear function of the fractional occupation numbers (removing most of the electron self-interaction). This allows the calculation of electronic transitions with accuracy unseen before, as demonstrated on the single-photon emitter NV(-) center in diamond and on polaronic states in TiO2. Having a reliable tool for electronic structure calculations, theory can contribute to the understanding of complicated cases of light-matter interaction. Two examples are considered here: surface termination effects on the blinking and bleaching of the light-emission of the NV(-) center in diamond, and on the efficiency of photocatalytic water-splitting by TiO2. Finally, an outlook is presented for the application of hybrid functionals in other materials, as, e.g., ZnO, Ga2O3 or CuGaS2.

  8. Complex layered materials and periodic electromagnetic band-gap structures: Concepts, characterizations, and applications

    Science.gov (United States)

    Mosallaei, Hossein

    The main objective of this dissertation is to characterize and create insight into the electromagnetic performances of two classes of composite structures, namely, complex multi-layered media and periodic Electromagnetic Band-Gap (EBG) structures. The advanced and diversified computational techniques are applied to obtain their unique propagation characteristics and integrate the results into some novel applications. In the first part of this dissertation, the vector wave solution of Maxwell's equations is integrated with the Genetic Algorithm (GA) optimization method to provide a powerful technique for characterizing multi-layered materials, and obtaining their optimal designs. The developed method is successfully applied to determine the optimal composite coatings for Radar Cross Section (RCS) reduction of canonical structures. Both monostatic and bistatic scatterings are explored. A GA with hybrid planar/curved surface implementation is also introduced to efficiently obtain the optimal absorbing materials for curved structures. Furthermore, design optimization of the non-uniform Luneburg and 2-shell spherical lens antennas utilizing modal solution/GA-adaptive-cost function is presented. The lens antennas are effectively optimized for both high gain and suppressed grating lobes. The second part demonstrates the development of an advanced computational engine, which accurately computes the broadband characteristics of challenging periodic electromagnetic band-gap structures. This method utilizes the Finite Difference Time Domain (FDTD) technique with Periodic Boundary Condition/Perfectly Matched Layer (PBC/PML), which is efficiently integrated with the Prony scheme. The computational technique is successfully applied to characterize and present the unique propagation performances of different classes of periodic structures such as Frequency Selective Surfaces (FSS), Photonic Band-Gap (PBG) materials, and Left-Handed (LH) composite media. The results are

  9. High-frequency microstrip dual-band bandpass filter fabricated using FR-4 glass epoxy material

    Science.gov (United States)

    Challal, Mouloud; Mermoul, Ali; Hocine, Kenza

    2017-12-01

    In this paper, design, fabrication and measurement of a novel microstrip dual-band bandpass filter (BPF) structure with a compact size using FR-4 glass epoxy material is presented. The filter structure is composed of folded non-uniform meander resonators. The proposed filter with a total size of 0.24λg  ×  0.16λg is designed to exhibit two passbands centred at 2.68 GHz and 5.64 GHz with fractional bandwidths of 25.38% and 10.4%, respectively. The simulation and experimental measurement results are basically in good agreement which validate the proposed approach.

  10. Ultrathin high band gap solar cells with improved efficiencies from the world's oldest photovoltaic material.

    Science.gov (United States)

    Todorov, Teodor K; Singh, Saurabh; Bishop, Douglas M; Gunawan, Oki; Lee, Yun Seog; Gershon, Talia S; Brew, Kevin W; Antunez, Priscilla D; Haight, Richard

    2017-09-25

    Selenium was used in the first solid state solar cell in 1883 and gave early insights into the photoelectric effect that inspired Einstein's Nobel Prize work; however, the latest efficiency milestone of 5.0% was more than 30 years ago. The recent surge of interest towards high-band gap absorbers for tandem applications led us to reconsider this attractive 1.95 eV material. Here, we show completely redesigned selenium devices with improved back and front interfaces optimized through combinatorial studies and demonstrate record open-circuit voltage (V OC ) of 970 mV and efficiency of 6.5% under 1 Sun. In addition, Se devices are air-stable, non-toxic, and extremely simple to fabricate. The absorber layer is only 100 nm thick, and can be processed at 200 ˚C, allowing temperature compatibility with most bottom substrates or sub-cells. We analyze device limitations and find significant potential for further improvement making selenium an attractive high-band-gap absorber for multi-junction device applications.Wide band gap semiconductors are important for the development of tandem photovoltaics. By introducing buffer layers at the front and rear side of solar cells based on selenium; Todorov et al., reduce interface recombination losses to achieve photoconversion efficiencies of 6.5%.

  11. Tunable PhoXonic Band Gap Materials from Self-Assembly of Block Copoliymers and Colloidal Nanocrystals (NBIT Phase II)

    Science.gov (United States)

    2011-05-06

    Activities: Hysteric Tunable Photonic Gels and Their Applications Photonic band gap ( PBG ) materials have been of great interest due to their potential...applications in science and technology. Their applications can be further extended when the PBG becomes tunable against various chemical and...electrical stimuli. Recently, it was found that tunable photonic band gap materials can be achieved by incorporating stimuli-responsive smart gels into PBG

  12. Role of Short-Range Order and Hyperuniformity in the Formation of Band Gaps in Disordered Photonic Materials.

    Science.gov (United States)

    Froufe-Pérez, Luis S; Engel, Michael; Damasceno, Pablo F; Muller, Nicolas; Haberko, Jakub; Glotzer, Sharon C; Scheffold, Frank

    2016-07-29

    We study photonic band gap formation in two-dimensional high-refractive-index disordered materials where the dielectric structure is derived from packing disks in real and reciprocal space. Numerical calculations of the photonic density of states demonstrate the presence of a band gap for all polarizations in both cases. We find that the band gap width is controlled by the increase in positional correlation inducing short-range order and hyperuniformity concurrently. Our findings suggest that the optimization of short-range order, in particular the tailoring of Bragg scattering at the isotropic Brillouin zone, are of key importance for designing disordered PBG materials.

  13. Conduction mechanism in Polyaniline-flyash composite material for shielding against electromagnetic radiation in X-band & Ku band

    Directory of Open Access Journals (Sweden)

    Avanish Pratap Singh

    2011-06-01

    Full Text Available β–Naphthalene sulphonic acid (β–NSA doped polyaniline (PANI–flyash (FA composites have been prepared by chemical oxidative polymerization route whose conductivity lies in the range 2.37–21.49 S/cm. The temperature dependence of electrical conductivity has also been recorded which shows that composites follow Mott's 3D–VRH model. SEM images demonstrate that β–NSA leads to the formation of the tubular structure with incorporated flyash phase. TGA studies show the improvement in thermal stability of composites with increase in loading level of flyash. Complex parameters i.e. permittivity (ɛ* = ɛ′- iɛ″ and permeability (μ*=μ′- iμ″ of PANI-FA composites have been calculated from experimental scattering parameters (S11 & S21 using theoretical calculations given in Nicholson–Ross and Weir algorithms. The microwave absorption properties of the composites have been studied in X-band (8.2 – 12.4 GHz & Ku–Band (12.4 – 18 GHz frequency range. The maximum shielding effectiveness observed was 32dB, which strongly depends on dielectric loss and volume fraction of flyash in PANI matrix.

  14. FY2009 Annual Progress Report for Propulsion Materials

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2010-01-16

    The Propulsion Materials program focuses on enabling and innovative materials technologies that are critical in improving the efficiency of advanced engines. Projects within the Propulsion Materials Program address materials concerns that directly impact the critical technical barriers in each of these programs—barriers such as fuel efficiency, thermal management, emissions reduction, and reduced manufacturing costs.

  15. Band Gap Tuning in 2D Layered Materials by Angular Rotation

    Directory of Open Access Journals (Sweden)

    Javier Polanco-Gonzalez

    2017-02-01

    Full Text Available We present a series of computer-assisted high-resolution transmission electron (HRTEM simulations to determine Moiré patters by induced twisting effects between slabs at rotational angles of 3°, 5°, 8°, and 16°, for molybdenum disulfide, graphene, tungsten disulfide, and tungsten selenide layered materials. In order to investigate the electronic structure, a series of numerical simulations using density functional methods (DFT methods was completed using Cambridge serial total energy package (CASTEP with a generalized gradient approximation to determine both the band structure and density of states on honeycomb-like new superlattices. Our results indicated metallic transitions when the rotation approached 8° with respect to each other laminates for most of the two-dimensional systems that were analyzed.

  16. Hematite from Natural Iron Stones as Microwave Absorbing Material on X-Band Frequency Ranges

    Science.gov (United States)

    Zainuri, Mochamad

    2017-05-01

    This study has been investigated the effect of hematite as microwave absorbing materials (RAM) on X-Band frequency ranges. Hematite was succesfully processed by coprecipitation method and calcined at 500 °C for 5 hour. It was synthesized from natural iron stones from Tanah Laut, South Kalimantan, Indonesia. The products were characterized by X-ray diffraxtion (XRD), conductivity measurement, Vibrating Sample Magnetometer (VSM), and Vector Network Analyzer (VNA). The result was shown that hematite has conductivity value on (2.5-3).10-7 S/cm and be included as dielectric materials. The hysterisis curve was shown that hematite was a super paramagnetic materials. The product was mixed on paint with procentage 10% of total weight and coated on steel grade AH36 with spray methods. Then, the maximum of reflection loss on x - band’s frequency range (8,2-12,4) GHz was -7 dB on frequency of 10.5 GHz. It mean that almost 50% electromagnetic energy was absorbed by hematite.

  17. Advanced High-Temperature Engine Materials Technology Progresses

    Science.gov (United States)

    1997-01-01

    The objective of the Advanced High Temperature Engine Materials Technology Program (HITEMP) at the NASA Lewis Research Center is to generate technology for advanced materials and structural analysis that will increase fuel economy, improve reliability, extend life, and reduce operating costs for 21st century civil propulsion systems. The primary focus is on fan and compressor materials (polymer-matrix composites - PMC's), compressor and turbine materials (superalloys, and metal-matrix and intermetallic-matrix composites - MMC's and IMC's), and turbine materials (ceramic-matrix composites - CMC's). These advanced materials are being developed in-house by Lewis researchers and on grants and contracts.

  18. Research Progress of Building Materials Used in Construction Land

    Science.gov (United States)

    Niu, Yan

    2018-01-01

    Construction land preparation is an important aspect of land remediation project. The research of materials in the process of land improvement is the foundation and the core. Therefore, it is necessary to study the materials that may be involved in the process of building land preparation. In this paper, the research on the construction materials such as recycled concrete, geosynthetics, soil stabilizers, soil improvers, building insulation materials and inorganic fibrous insulation materials, which are commonly used in construction sites, is reviewed and discussed in this paper. Land remediation project involved in the construction of land materials to provide reference.

  19. Isotopic power materials development. Quarterly progress report for period ending June 30, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Schaffhauser, A.C.

    1976-09-01

    Research progress is reported on: (1) high-temperature alloys for space isotopic heat sources; (2) physical and mechanical metallurgy of heat-source containment materials; (3) isotope brayton system materials support; and (4) space nuclear flight systems hardware. (TFD)

  20. Advances in materials science, Metals and Ceramics Division. Triannual progress report, October 1979-January 1980

    Energy Technology Data Exchange (ETDEWEB)

    1980-03-31

    Progress is summarized concerning magnetic fusion energy materials, laser fusion energy, aluminium-air battery and vehicle, geothermal research, oil-shale research, nuclear waste management, office of basic energy sciences research, and materials research notes. (FS)

  1. Progress on research of materials science and biotechnology by ion beam application

    Energy Technology Data Exchange (ETDEWEB)

    Ishigaki, Isao [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    Research of materials science and biotechnology by ion beam application in Takasaki Establishment was reviewed. Especially, the recent progresses of research on semiconductors in space, creation of new functional materials and topics in biotechnology were reported. (author)

  2. FY2008 Annual Progress Report for Propulsion Materials

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-01-01

    This program focuses on enabling and innovative materials technologies that are critical in improving the efficiency of advanced engines providing enabling materials support for combustion, hybrid, and power electronics development.

  3. Chemistry and materials science progress report, FY 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    Research is reported in the areas of surface science, fundamentals of the physics and processing of metals, energetic materials, transactinide materials and properties and other indirectly related areas of weapons research.

  4. FY2010 Annual Progress Report for Propulsion Materials

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Patrick B. [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States); Schutte, Carol L. [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States); Gibbs, Jerry L. [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

    2011-01-01

    The Propulsion Materials Technology actively supports the energy security and reduction of greenhouse emissions goals of the Vehicle Technologies Program by developing advanced materials that enable development of higher efficiency powertrains for ground transportation. Propulsion Materials works closely with the other disciplines within the VT Program to identify the materials properties essential for the development of cost-effective, highly efficient, and environmentally friendly next-generation heavy and light duty powertrains.

  5. Research on the effects of geometrical and material uncertainties on the band gap of the undulated beam

    Science.gov (United States)

    Li, Yi; Xu, Yanlong

    2017-09-01

    Considering uncertain geometrical and material parameters, the lower and upper bounds of the band gap of an undulated beam with periodically arched shape are studied by the Monte Carlo Simulation (MCS) and interval analysis based on the Taylor series. Given the random variations of the overall uncertain variables, scatter plots from the MCS are used to analyze the qualitative sensitivities of the band gap respect to these uncertainties. We find that the influence of uncertainty of the geometrical parameter on the band gap of the undulated beam is stronger than that of the material parameter. And this conclusion is also proved by the interval analysis based on the Taylor series. Our methodology can give a strategy to reduce the errors between the design and practical values of the band gaps by improving the accuracy of the specially selected uncertain design variables of the periodical structures.

  6. Design of an ultra-thin absorption layer with magnetic materials based on genetic algorithm at the S band

    Science.gov (United States)

    Wang, Fang; Yang, Xiaoning; Liu, Xiaoning; Niu, Tiaoming; Wang, Jing; Mei, Zhonglei; Jian, Yabin

    2018-04-01

    In this work, we design an ultra-thin absorption coating at the S band, and the total thickness is less than 2 mm. For incident angle less than 30 degree and the whole S band, the reflection is less than -5 dB. The coating is constructed with 4/3 layers of magnetic material with different thicknesses, which are optimized by using genetic algorithm. Analytic and simulation results confirm the correctness of the design.

  7. Advanced Industrial Materials Program. Annual progress report, FY 1993

    Energy Technology Data Exchange (ETDEWEB)

    Stooksbury, F. [comp.

    1994-06-01

    Mission of the AIM program is to commercialize new/improved materials and materials processing methods that will improve energy efficiency, productivity, and competitiveness. Program investigators in the DOE national laboratories are working with about 100 companies, including 15 partners in CRDAs. Work is being done on intermetallic alloys, ceramic composites, metal composites, polymers, engineered porous materials, and surface modification. The program supports other efforts in the Office of Industrial Technologies to assist the energy-consuming process industries. The aim of the AIM program is to bring materials from basic research to industrial application to strengthen the competitive position of US industry and save energy.

  8. FY2014 Propulsion Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-05-01

    The Propulsion Materials Program actively supports the energy security and reduction of greenhouse emissions goals of VTO by investigating and identifying the materials properties that are most essential for continued development of cost-effective, highly efficient, and environmentally friendly next-generation heavy and light-duty powertrains. The technical approaches available to enhance propulsion systems focus on improvements in both vehicle efficiency and fuel substitution, both of which must overcome the performance limitations of the materials currently in use. Propulsion Materials Program activities work with national laboratories, industry experts, and VTO powertrain systems (e.g., Advanced Combustion Engines [ACE], Advanced Power Electronics and Electrical Machines [APEEM], and fuels) teams to develop strategies that overcome materials limitations in future powertrain performance. The technical maturity of the portfolio of funded projects ranges from basic science to subsystem prototype validation. Projects within a Propulsion Materials Program activity address materials concerns that directly impact critical technology barriers within each of the above programs, including barriers that impact fuel efficiency, thermal management, emissions reduction, improved reliability, and reduced manufacturing costs. The program engages only the barriers that result from material property limitations and represent fundamental, high-risk materials issues.

  9. FY2014 Lightweight Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-03-01

    The Lightweight Materials research and development (R&D) area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing lightweight materials for passenger and commercial vehicles.

  10. FY2013 Lightweight Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-02-01

    As part of the U.S. Department of Energy’s (DOE’s) Vehicle Technologies Program (VTO), the Lightweight Materials (LM) activity focuses on the development and validation of advanced materials and manufacturing technologies to significantly reduce light and heavy duty vehicle weight without compromising other attributes such as safety, performance, recyclability, and cost.

  11. FY2010 Annual Progress Report for Lightweighting Materials

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-01-15

    The Lightweight Materials activity (LM) within the Vehicle Technologies Program focuses on the development and validation of advanced materials and manufacturing technologies to significantly reduce light and heavy duty vehicle weight without compromising other attributes such as safety, performance, recyclability, and cost.

  12. Advanced Industrial Materials (AIM) Program: Annual progress report FY 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    In many ways, the Advanced Industrial Materials (AIM) Program underwent a major transformation in Fiscal Year 1995 and these changes have continued to the present. When the Program was established in 1990 as the Advanced Industrial Concepts (AIC) Materials Program, the mission was to conduct applied research and development to bring materials and processing technologies from the knowledge derived from basic research to the maturity required for the end use sectors for commercialization. In 1995, the Office of Industrial Technologies (OIT) made radical changes in structure and procedures. All technology development was directed toward the seven ``Vision Industries`` that use about 80% of industrial energy and generated about 90% of industrial wastes. The mission of AIM has, therefore, changed to ``Support development and commercialization of new or improved materials to improve productivity, product quality, and energy efficiency in the major process industries.`` Though AIM remains essentially a National Laboratory Program, it is essential that each project have industrial partners, including suppliers to, and customers of, the seven industries. Now, well into FY 1996, the transition is nearly complete and the AIM Program remains reasonably healthy and productive, thanks to the superb investigators and Laboratory Program Managers. This Annual Report for FY 1995 contains the technical details of some very remarkable work by the best materials scientists and engineers in the world. Areas covered here are: advanced metals and composites; advanced ceramics and composites; polymers and biobased materials; and new materials and processes.

  13. Advanced Industrial Materials (AIM) Program. Annual progress report, FY 1994

    Energy Technology Data Exchange (ETDEWEB)

    Sorrell, C.A.

    1995-05-01

    The Advanced Industrial Materials Program is a part of the Office of Industrial Technologies (OIT), Energy Efficiency and Renewable Energy in the Department of Energy. The mission of the AIM Program is to conduct applied research, development, and applications engineering work, in partnership with industry, to commercialize new or improved materials and materials processing methods that will improve energy efficiency, productivity, and competitiveness. AIM is responsible for identifying, supporting, and coordinating multidisciplinary projects to solve identified industrial needs and transferring the technology to the industrial sector. Program investigators in the DOE National Laboratories are working closely with approximately 100 companies, including 15 partners in Cooperative Research and Development Agreements. Work is being done in a wide variety of materials technologies, including intermetallic alloys, ceramic composites, metal composites, polymers, engineered porous materials, and surface modification. The Program supports other efforts in the Office of Industrial Technologies to assist the energy consuming process industries, including forest products, glass, steel, aluminum, foundries, chemicals, and refineries. To support OITs {open_quotes}Industries of the Future{close_quotes} initiatives and to improve the relevance of materials research, assessments of materials needs and opportunities in the process industries are being made. These assessments are being used for program planning and priority setting; support of work to satisfy those needs is being provided. Many new materials that have come into the marketplace in recent years, or that will be available for commercial use within a few more years, offer substantial benefits to society. This document contains 28 reports on advanced materials research. Individual reports have been processed separately for entry onto the Department of Energy databases.

  14. Chemistry and Materials Science progress report, first half FY 1992

    International Nuclear Information System (INIS)

    1992-07-01

    This report contains sections on: Fundamentals of the physics and processing of metals; interfaces, adhesion, and bonding; energetic materials; plutonium research; synchrotron radiation-based materials science; atomistic approach to the interaction of surfaces with the environment: actinide studies; properties of carbon fibers; buried layer formation using ion implantation; active coherent control of chemical reaction dynamics; inorganic and organic aerogels; synthesis and characterization of melamine-formaldehyde aerogels; structural transformation and precursor phenomena in advanced materials; magnetic ultrathin films, surfaces, and overlayers; ductile-phase toughening of refractory-metal intermetallics; particle-solid interactions; electronic structure evolution of metal clusters; and nanoscale lithography induced chemically or physically by modified scanned probe microscopy

  15. Science of materials. Progress report, January 1-December 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    The research program includes studies of the microchemistry, microstructure, deformation, corrosion and fracture of metals, ceramics and alloy materials, of the hydrogen embrittlement of metals, the mechanism of heat transfer across interfacts, catalytic properties of surfaces, and erosion of surfaces by fluid suspended particles. The structure of liquids, polymers and disordered solids is under investigation with emphasis on molecular interactions and bonding, on ionic conduction, phase transitions and radiation damage. Ferro- and pyro-electric materials with potential for solar energy applications are under development. The study of optical properties includes the mechanism of luminescence, the design of molecular photoreceptors, and new semiconductor materials for photovoltaic devices.

  16. Science of materials. Progress report, January 1-December 31, 1979

    International Nuclear Information System (INIS)

    1979-01-01

    The research program includes studies of the microchemistry, microstructure, deformation, corrosion and fracture of metals, ceramics and alloy materials, of the hydrogen embrittlement of metals, the mechanism of heat transfer across interfacts, catalytic properties of surfaces, and erosion of surfaces by fluid suspended particles. The structure of liquids, polymers and disordered solids is under investigation with emphasis on molecular interactions and bonding, on ionic conduction, phase transitions and radiation damage. Ferro- and pyro-electric materials with potential for solar energy applications are under development. The study of optical properties includes the mechanism of luminescence, the design of molecular photoreceptors, and new semiconductor materials for photovoltaic devices

  17. Chemistry and Materials Science progress report, FY 1994. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    Thrust areas of the weapons-supporting research include surface science, fundamentals of the physics and processing of metals, energetic materials, etc. The laboratory directed R and D include director`s initiatives, individual projects, and transactinium science studies.

  18. Hypersonic modulation of light in three-dimensional photonic and phononic band-gap materials.

    Science.gov (United States)

    Akimov, A V; Tanaka, Y; Pevtsov, A B; Kaplan, S F; Golubev, V G; Tamura, S; Yakovlev, D R; Bayer, M

    2008-07-18

    The elastic coupling between the a-SiO2 spheres composing opal films brings forth three-dimensional periodic structures which besides a photonic stop band are predicted to also exhibit complete phononic band gaps. The influence of elastic crystal vibrations on the photonic band structure has been studied by injection of coherent hypersonic wave packets generated in a metal transducer by subpicosecond laser pulses. These studies show that light with energies close to the photonic band gap can be efficiently modulated by hypersonic waves.

  19. Recent Progress on PEDOT-Based Thermoelectric Materials.

    Science.gov (United States)

    Wei, Qingshuo; Mukaida, Masakazu; Kirihara, Kazuhiro; Naitoh, Yasuhisa; Ishida, Takao

    2015-02-16

    The thermoelectric properties of poly(3,4-ethylenedioxythiophene) (PEDOT)-based materials have attracted attention recently because of their remarkable electrical conductivity, power factor, and figure of merit. In this review, we summarize recent efforts toward improving the thermoelectric properties of PEDOT-based materials. We also discuss thermoelectric measurement techniques and several unsolved problems with the PEDOT system such as the effect of water absorption from the air and the anisotropic thermoelectric properties. In the last part, we describe our work on improving the power output of thermoelectric modules by using PEDOT, and we outline the potential applications of polymer thermoelectric generators.

  20. Recent Progress on PEDOT-Based Thermoelectric Materials

    Directory of Open Access Journals (Sweden)

    Qingshuo Wei

    2015-02-01

    Full Text Available The thermoelectric properties of poly(3,4-ethylenedioxythiophene (PEDOT-based materials have attracted attention recently because of their remarkable electrical conductivity, power factor, and figure of merit. In this review, we summarize recent efforts toward improving the thermoelectric properties of PEDOT-based materials. We also discuss thermoelectric measurement techniques and several unsolved problems with the PEDOT system such as the effect of water absorption from the air and the anisotropic thermoelectric properties. In the last part, we describe our work on improving the power output of thermoelectric modules by using PEDOT, and we outline the potential applications of polymer thermoelectric generators.

  1. Recent Progress on PEDOT-Based Thermoelectric Materials

    Science.gov (United States)

    Wei, Qingshuo; Mukaida, Masakazu; Kirihara, Kazuhiro; Naitoh, Yasuhisa; Ishida, Takao

    2015-01-01

    The thermoelectric properties of poly(3,4-ethylenedioxythiophene) (PEDOT)-based materials have attracted attention recently because of their remarkable electrical conductivity, power factor, and figure of merit. In this review, we summarize recent efforts toward improving the thermoelectric properties of PEDOT-based materials. We also discuss thermoelectric measurement techniques and several unsolved problems with the PEDOT system such as the effect of water absorption from the air and the anisotropic thermoelectric properties. In the last part, we describe our work on improving the power output of thermoelectric modules by using PEDOT, and we outline the potential applications of polymer thermoelectric generators. PMID:28787968

  2. Advanced Industrial Materials (AIM) Program annual progress report, FY 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    The Advanced Industrial Materials (AIM) Program is a part of the Office of Industrial Technologies (OIT), Energy Efficiency and Renewable Energy, US Department of Energy (DOE). The mission of AIM is to support development and commercialization of new or improved materials to improve energy efficiency, productivity, product quality, and reduced waste in the major process industries. OIT has embarked on a fundamentally new way of working with industries--the Industries of the Future (IOF) strategy--concentrating on the major process industries that consume about 90% of the energy and generate about 90% of the waste in the industrial sector. These are the aluminum, chemical, forest products, glass, metalcasting, and steel industries. OIT has encouraged and assisted these industries in developing visions of what they will be like 20 or 30 years into the future, defining the drivers, technology needs, and barriers to realization of their visions. These visions provide a framework for development of technology roadmaps and implementation plans, some of which have been completed. The AIM Program supports IOF by conducting research and development on materials to solve problems identified in the roadmaps. This is done by National Laboratory/industry/university teams with the facilities and expertise needed to develop new and improved materials. Each project in the AIM Program has active industrial participation and support.

  3. Chemistry and Materials Science. Progress report, first half, FY 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-01

    Thrust areas of the weapons-supporting research are growth, structure, and reactivity of surfaces and thin films; uranium research; physics and processing of metals; energetic materials; etc. The laboratory-directed R and D include director`s initiatives and individual projects, and transactinium institute studies.

  4. Progress in synthesis and characterization of energy materials. Preface

    OpenAIRE

    Hoeche, T.; Weidenkaff, A.; Terasaki, I.

    2013-01-01

    The looming shortage of natural resources drives the scientific and commercial interest in renewable energies, energy recovery, and power saving. In this context, the development of novel approaches, replacement of toxic and less available resources, and improvement of existing technologies to synthesize suitable materials is pivotal.

  5. Fusion materials semiannual progress report for period ending December 31, 1999

    International Nuclear Information System (INIS)

    Burn, G.

    2000-01-01

    This is the twenty-seventh in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components

  6. Fusion materials semiannual progress report for period ending December 31, 1999

    Energy Technology Data Exchange (ETDEWEB)

    Burn, G.

    2000-03-01

    This is the twenty-seventh in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components.

  7. Synchrotron Studies of Narrow Band and Low-Dimensional Materials. Final Report for July 1, 1990---December 31, 2002

    Energy Technology Data Exchange (ETDEWEB)

    Allen, J. W.

    2003-05-13

    This report summarizes a 12-year program of various kinds of synchrotron spectroscopies directed at the electronic structures of narrow band and low-dimensional materials that display correlated electron behaviors such as metal-insulator transitions, mixed valence, superconductivity, Kondo moment quenching, heavy Fermions, and non-Fermi liquid properties.

  8. Materials Science Division progress report 1986-1988

    International Nuclear Information System (INIS)

    Kumar, Vijay; Vasumathi, D.; Chandra Sekhar, N.V.

    1990-01-01

    This is a report on the various Research and Developmental (R and D) activities carried out in the Materials Science Division during the period 1986-88. Most contributions have been presented in the form of abstracts and wherever possible results of several contributions on a related problem have been consolidated into one. The R and D activities covered the following areas: (1) quasicrystalline phase, (2) high temperature superconducting behaviour in metal oxides, (3) physics of colloidal suspensions, (4) behaviour of materials under high pressure, (5) radiation effects in complex alloy systems, (6) inert gas behaviour in metals, and production of crystals, particularly of volatile semiconducting compounds. The lists of publications by the members of the Division and seminars held during 1986-88 are given at the end of the report. (a uthor)

  9. Recent progress in supercapacitors: from materials design to system construction.

    Science.gov (United States)

    Wang, Yonggang; Xia, Yongyao

    2013-10-04

    Supercapacitors are currently attracting intensive attention because they can provide energy density by orders of magnitude higher than dielectric capacitors, greater power density, and longer cycling ability than batteries. The main challenge for supercapacitors is to develop them with high energy density that is close to that of a current rechargeable battery, while maintaining their inherent characteristics of high power and long cycling life. Consequently, much research has been devoted to enhance the performance of supercapacitors by either maximizing the specific capacitance and/or increasing the cell voltage. The latest advances in the exploration and development of new supercapacitor systems and related electrode materials are highlighted. Also, the prospects and challenges in practical application are analyzed, aiming to give deep insights into the material science and electrochemical fields. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Advanced Industrial Materials (AIM) program. Annual progress report. FY 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    The Advanced Industrial Materials (AIM) Program underwent a major transformation in Fiscal Year 1995 and these changes have continued to the present. When the Program was established in 1990 as the Advanced Industrial Concepts (AIC) Materials Program, the mission was to conduct applied research and development to bring materials and processing technologies from the knowledge derived from basic research to the maturity required for the end use sectors for commercialization. In 1995, the Office of Industrial Technologies (OIT) made radical changes in structure and procedures. All technology development was directed toward the seven `Vision Industries` that use about 80% of industrial energy and generated about 90% of industrial wastes. These are: aluminium; chemical; forest products; glass; metal casting; refineries; and steel. OIT is working with these industries, through appropriate organizations, to develop Visions of the desired condition of each industry some 20 or 25 years in the future and then to prepare Road Maps and Implementation Plans to enable them to reach their goals. The mission of AIM has, therefore, changed to `Support development and commercialization of new or improved materials to improve productivity, product quality, and energy efficiency in the major process industries.` Though AIM remains essentially a National Laboratory Program, it is necessary that each project have industrial partners, including suppliers to, and customers of, the seven industries. Now, well into FY 1996, the transition is nearly complete and the AIM Program remains healthy and productive, thanks to the superb investigators and Laboratory Program Managers. Separate abstracts have been indexed into the energy database for articles from this report.

  11. Band diagram determination of MOS structures with different gate materials on 3C-SiC substrate

    Science.gov (United States)

    Piskorski, K.; Przewlocki, H.; Esteve, R.; Bakowski, M.

    2012-03-01

    MOS capacitors were fabricated on 3C-SiC n-type substrate (001) with a 10-μm N-type epitaxial layer. An SiO2 layer of the thickness tOX ≈55 nm was deposited by PECVD. Circular Al, Ni, and Au gate contacts 0.7 mm in diameter were formed by ion beam sputtering and lift-off. Energy band diagrams of the MOS capacitors were determined using the photoelectric, electric, and optical measurement methods. Optical method (ellipsometry) was used to determine the gate and dielectric layer thicknesses and their optical indices: the refraction n and the extinction k coefficients. Electrical method of C = f(VG) characteristic measurements allowed to determine the doping density ND and the flat band voltage VFB in the semiconductor. Most of the parameters which were necessary for the construction of the band diagrams and for determination of the basic physical properties of the structures (e.g. the effective contact potential difference ϕMS) were measured by several photoelectric methods and calculated using the measurement data. As a result, complete energy band diagrams have been determined for MOS capacitors with three different gate materials and they are demonstrated for two different gate voltages VG: for the flat-band in the semiconductor (VG = VFB) and for the flat-band in the dielectric (VG = VG0).

  12. Research and Application Progress of Silicone Rubber Materials in Aviation

    Directory of Open Access Journals (Sweden)

    HUANG Yanhua

    2016-06-01

    Full Text Available The research progress of heat resistance, cold resistance, electrical conductivity and damping properties of aviation silicone rubber were reviewed in this article. The heat resistance properties of silicone rubber can be enhanced by changing the molecular structure (main chain, end-group, side chain and molecular weight of the gum and adding special heat-resistance filler. The cold resistance of aviation silicone rubber can be enhanced by adjusting the side chain molecular structure of the gum and the content of different gum chain. The electrical conductivity of silicone rubber can be improved by optimizing, blending and dispersing of conductive particles. The damping property of silicone rubber can be improved by designing and synthesizing of high-molecular polysiloxane damping agent. Furthermore, the application of aviation silicone rubber used in high-low temperature seal, electrical conduction and vibration damping technology are also summarized, and the high performance (for example long-term high temperature resistance, ultralow temperature resistance, high electromagnetic shelding, long-term fatigue resistance vibration damping, quasi constant modulus and so on of special silicone rubber is the future direction of aviation silicone rubber.

  13. [Research progress of Chinese herbal medicine raw materials in cosmetics].

    Science.gov (United States)

    Xie, Yan-jun; Kong, Wei-jun; Yang, Mei-hua; Yang, Shi-hai

    2015-10-01

    Advocating green, nature, environmental protection, safety and the pursuit of efficacy are the trends of cosmetics in the world. In recent years, more and more Chinese herbal extracts with mild, high safety and small irritation are applied to cosmetics as the natural additives. This has become a new hot spot. The recent application advances of Chinese medicine raw materials in cosmetics are overviewed according to their main functions. This review will provide useful references for the future development and application of Chinese medicinal herbs cosmetics.

  14. Materi Dakwah Pada Grup Ban Non-Religi(Analisis Pesan Dakwah Dalam Lirik Lagu Grub Band GIGI)

    OpenAIRE

    Aripudin, Acep; Ridwan, M. Roiz

    2009-01-01

    Not all aspects of music identical with caprice and banter, but they can also serve as medium of da'wah material conveyor. For example, band group lyric Fills of GIGI, of five song sample that analyzed by researcher for example: Reach for victory, I'tiraf, Peace, Apostle pine and God. Every thing gets classified massage da'wah. With this songs Groups A Brass Band GIGI intend to give resuscitations and asking out to fanses for always near his self on The Infinite Creator Mighty.

  15. Interfacial reactions and band offsets in the AlSb/GaSb/ZnTe material system

    OpenAIRE

    Yu, E. T.; Phillips, M. C.; Chow, D. H.; Collins, D. A.; Wang, M. W.; McCaldin, J. O.; McGill, T. C.

    1992-01-01

    We have used x-ray photoelectron spectroscopy to measure valence-band offsets in situ for AlSb/ZnTe, AlSb/GaSb, and GaSb/ZnTe(100) heterojunctions grown by molecular-beam epitaxy. For the AlSb/ZnTe heterojunction, a valence-band offset ΔEv=0.42±0.07 eV was obtained. Our data indicated that an intermediate compound, containing Al and Te, was formed at the AlSb/ZnTe(100) interface. Measurements of the AlSb/GaSb and GaSb/ZnTe valence-band offsets demonstrated a clear violation of band offset tra...

  16. Radiation effects in nuclear waste materials. 1997 annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Weber, W.J.; Corrales, L.R.

    1997-06-01

    'The objective of this multidisciplinary, multi-institutional research effort is to develop a fundamental understanding at the atomic, microscopic, and macroscopic levels of radiation effects in glass and ceramics. This research will provide the underpinning science and models for evaluation and performance assessments of glass and ceramic waste forms for the immobilization and disposal of high-level tank waste, plutonium residues and scrap, and excess weapons plutonium. Studies will focus on the effects of ionization and elastic collision interactions on defect production, defect interactions, diffusion, solid-state phase transformations, and gas accumulation using actinide-containing materials, gamma irradiation, ion-beam irradiation, and electron-beam irradiation to simulate the effects of a-decay and p-decay on nuclear waste glasses and ceramics. This program will exploit a variety of structural, optical, and spectroscopic probes to characterize the nature and behavior of the defects, defect aggregates, and phase transforma-tions. Computer simulation techniques will be used to determine defect production, calculate defect stability, defect energies, damage processes within an a-recoil cascade, and defect/gas diffusion and interactions. A number of irradiation facilities and capabilities will be used, including user facilities at several national laboratories, to study the effects of irradiation under different conditions.'

  17. Renormalization of the quasiparticle band gap in doped two-dimensional materials from many-body calculations

    Science.gov (United States)

    Gao, Shiyuan; Yang, Li

    2017-10-01

    Doped free carriers can substantially renormalize electronic self-energy and quasiparticle band gaps of two-dimensional (2D) materials. However, it is still challenging to quantitatively calculate this many-electron effect, particularly at the low doping density that is most relevant to realistic experiments and devices. Here we develop a first-principles-based effective-mass model within the G W approximation and show a dramatic band-gap renormalization of a few hundred meV for typical 2D semiconductors. Moreover, we reveal the roles of different many-electron interactions: The Coulomb-hole contribution is dominant for low doping densities while the screened-exchange contribution is dominant for high doping densities. Three prototypical 2D materials are studied by this method: h -BN , Mo S2 , and black phosphorus, covering insulators to semiconductors. Especially, anisotropic black phosphorus exhibits a surprisingly large band-gap renormalization because of its smaller density-of-state that enhances the screened-exchange interactions. Our work demonstrates an efficient way to accurately calculate band-gap renormalization and provides quantitative understanding of doping-dependent many-electron physics of general 2D semiconductors.

  18. Isotopic power materials development. Quarterly progress report for period ending December 31, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Schaffhauser, A.C.

    1977-06-01

    Research progress is reported on: (1) high-temperature alloys for space isotopic heat sources; (2) physical and mechanical metallurgy of heat source containment materials; (3) /sup 144/Cm fuel development; (4) terrestrial radioisotope applications; (5) selenide isotope generator system support; (6) isotope Brayton system materials support; and (7) space nuclear flight systems hardware. (TFD)

  19. Charge transfer bands in optical materials and related defect level location

    Science.gov (United States)

    Dorenbos, Pieter

    2017-07-01

    Charge transfer (CT)-bands, electron trapping, hole trapping, electron release, hole release, metal-to-metal-charge transfer, CT-luminescence, anomalous emission, impurity trapped exciton emission, inter-valence charge transfer, pair-emission, tunneling, photo-electron spectroscopy, redox potentials, photo-ionization, thermal-ionization. All these phenomena deal with the transfer of an electron from one atom in a compound to either another atom in the compound or to the ambient, i.e., outside the compound. The energy needed for, or released in, such transfer carries information on the electron binding energy in the defect levels with respect to the host band levels or the levels in the ambient. First the different types of charge transfer between a lanthanide and the host bands, and how they can be used to construct a host referred binding energy (HRBE) diagram, are reviewed. Then briefly the chemical shift model is introduced in order to convert the HRBE diagram into a vacuum referred binding energy diagram (VRBE). Next charge transfer between transition metal elements and host bands and between Bi3+ and host bands are treated, and finally electron transfer from one defect to another and to the ambient. Illustrating examples are provided.

  20. Fusion reactor materials. Semiannual progress report for period ending September 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Rowcliffe, A.F.; Burn, G.L.; Knee`, S.S.; Dowker, C.L. [comps.

    1994-02-01

    This is the fifteenth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following progress reports: Alloy Development for Irradiation Performance; Damage Analysis and Fundamental Studies; Special purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the U.S. Department of Energy. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide.

  1. Effect of Spindle Parameters of Woodworking Band Saw on the AE Value of Crack Band Saw Blade in Compound Material Processing (1)

    Science.gov (United States)

    Gao, Jin-gui; Jiang, Zhao-fang; Luo, Lai-peng

    2017-04-01

    Taking the MJ3210A motion band saw as the research object, the AE value of the band saw blade vibration was obtained by analyzing the VIBSYS vibration signal acquisition and analysis software system in Beijing, and the change of the AE value of the band saw and the crack was found out. The experimental results show that in the MJ3210A sports car sawing machine, the band saw blade with width of 130 mm is used, and the AE value of the cracked band saw blade is well in the high band saw blade AE value. Under the best working condition of the band saw, the band saw blade AE If the value exceeds 104.7 dB (A) above, it means that the band saw blade has at least one crack length greater than 1.38 mm for the crack defect and the need to replace the band saw blade in time. Different species with saw blade of the AE value is different, white pine wood minimum, the largest oak wood; according to a variety of wood processing AE instrument value to determine the band saw blade crack to the situation; so as to fully rational use of band saw blade, The failure and the degree of development to find a new method.

  2. Progress on laboratory studies of the immobilisation of plutonium contaminated materials (pcm)

    International Nuclear Information System (INIS)

    Awmack, A.F.; Hemingway, K.

    1984-09-01

    This report describes progress on laboratory scale investigations into immobilisation of Plutonium Contaminated Materials for the year ending August 1984. The work is a continuation of that previously reported though some new work is also included. The samples tested were shredded plastic materials and latex. Three areas of work are covered (1) ISO Leach Tests (2) Radiolysis and degradation of organic materials (3) Equilibrium Leach Tests. (author)

  3. Fusion Materials Semiannual Progress Report for Period Ending December 31, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Rowcliff, A.F.; Burn, G.

    1999-04-01

    This is the twenty-fifth in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. This effort forms one element of the materials program being conducted in support of the Fusion Energy Sciences Program of the U.S. Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately.

  4. Fusion Materials Semiannual Progress Report for the Period Ending June 30, 1999

    Energy Technology Data Exchange (ETDEWEB)

    Rowcliffe, A.F.

    1999-09-01

    This is the twenty-sixth in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. This effort forms one element of the materials program being conducted in support of the Fusion Energy Sciences Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and its reported separately.

  5. User-defined Material Model for Thermo-mechanical Progressive Failure Analysis

    Science.gov (United States)

    Knight, Norman F., Jr.

    2008-01-01

    Previously a user-defined material model for orthotropic bimodulus materials was developed for linear and nonlinear stress analysis of composite structures using either shell or solid finite elements within a nonlinear finite element analysis tool. Extensions of this user-defined material model to thermo-mechanical progressive failure analysis are described, and the required input data are documented. The extensions include providing for temperature-dependent material properties, archival of the elastic strains, and a thermal strain calculation for materials exhibiting a stress-free temperature.

  6. Functionally Graded Thermoelectric Material though One Step Band Gap and Dopant Engineering

    DEFF Research Database (Denmark)

    Jensen, Ellen Marie; Borup, Kasper Andersen; Cederkrantz, Daniel

    gradients. It has previously been shown that a large functionally graded thermoelectric single crystal can be synthesized by the Czochralski method (1). Utilizing element gradients inherent to the Czochralski process we have synthesized a Ge1-xSix:B crystal with a continuously varying x, band gap...

  7. Fusion materials semiannual progress report for period ending June 30, 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-08-01

    This is the twenty-second in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. This effort forms one element of the materials program being conducted in support of the Fusion Energy Sciences Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. Topics covered here are: vanadium alloys; silicon carbide composites; ferritic/martensitic steels; austenitic stainless steels; insulating ceramics and optical materials; solid breeding materials; radiation effects mechanistic studies and experimental methods; dosimetry damage parameters; activation calculations; materials engineering and design requirements; irradiation facilities; test matrices; and experimental methods.

  8. Effect of packing fraction on shear band formation in a granular material forced by a penetrometer.

    Science.gov (United States)

    Tapia, Franco; Espíndola, David; Hamm, Eugenio; Melo, Francisco

    2013-01-01

    Granular ensembles subjected to confinement forces can reach metastable states that often break down via formation of shear bands for sufficiently high deviatoric stress. In this article we investigate the flow induced in a granular ensemble that is perturbed by a vertically moving finger in a quasiplanar geometry. The flow exhibits spiral-like shear bands and evolves discontinuously in time, in concert with an oscillating penetration force. We characterize the nature of this nucleation-relaxation type process for loose to dense packing fractions. The nucleation dynamics is reasonably well described by a simple Mohr-Coulomb failure criterium in which the friction coefficient is a function of packing fraction. We contrast our findings with the recent work of Gravish et al. [Phys. Rev. Lett. 105, 128301 (2010)].

  9. Graphene nanoribbons as low band gap donor materials for organic photovoltaics: quantum chemical aided design.

    Science.gov (United States)

    Osella, Silvio; Narita, Akimitsu; Schwab, Matthias Georg; Hernandez, Yenny; Feng, Xinliang; Müllen, Klaus; Beljonne, David

    2012-06-26

    Graphene nanoribbons (GNRs) are strips of graphene cut along a specific direction that feature peculiar electronic and optical properties owing to lateral confinement effects. We show here by means of (time-dependent) density functional theory calculations that GNRs with properly designed edge structures fulfill the requirements in terms of electronic level alignment with common acceptors (namely, C(60)), solar light harvesting, and singlet-triplet exchange energy to be used as low band gap semiconductors for organic photovoltaics.

  10. Digital Processing of Speech Materials: A Critical-Band-Based Model of Speech Perception.

    Science.gov (United States)

    1980-07-16

    Fran Murphy, the 1979-1980 class of SPA graduate students and the Spirit within all things. This research was supported by the Applied Research...has been indirectly approached in the work of French and Steinberg (1947). The twenty-four critical bands found in pure tone psychoacoustic studies...is present as long as the most intense harmonics associated with each formant are separated by at least a critical bandwidth. Synthetic vowels

  11. Fusion materials semiannual progress report for the period ending June 30, 1998

    International Nuclear Information System (INIS)

    Burn, G.

    1998-09-01

    This is the twenty-fourth in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. This effort forms one element of the materials program being conducted in support of the Fusion Energy Sciences Program of the US Department of Energy. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database

  12. Fusion reactor materials semiannual progress report for the period ending March 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-01

    This is the fourteenth in a series of semiannual technical progress reports on fusion reactor materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the US Depart of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. Separate abstracts were prepared for each individual section.

  13. Fusion reactor materials semiannual progress report for the period ending March 31, 1993

    International Nuclear Information System (INIS)

    1993-07-01

    This is the fourteenth in a series of semiannual technical progress reports on fusion reactor materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the US Depart of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. Separate abstracts were prepared for each individual section

  14. Extended two-temperature model for ultrafast thermal response of band gap materials upon impulsive optical excitation

    International Nuclear Information System (INIS)

    Shin, Taeho; Teitelbaum, Samuel W.; Wolfson, Johanna; Nelson, Keith A.; Kandyla, Maria

    2015-01-01

    Thermal modeling and numerical simulations have been performed to describe the ultrafast thermal response of band gap materials upon optical excitation. A model was established by extending the conventional two-temperature model that is adequate for metals, but not for semiconductors. It considers the time- and space-dependent density of electrons photoexcited to the conduction band and accordingly allows a more accurate description of the transient thermal equilibration between the hot electrons and lattice. Ultrafast thermal behaviors of bismuth, as a model system, were demonstrated using the extended two-temperature model with a view to elucidating the thermal effects of excitation laser pulse fluence, electron diffusivity, electron-hole recombination kinetics, and electron-phonon interactions, focusing on high-density excitation

  15. Recent progress in research on tungsten materials for nuclear fusion applications in Europe

    Science.gov (United States)

    Rieth, M.; Dudarev, S. L.; Gonzalez de Vicente, S. M.; Aktaa, J.; Ahlgren, T.; Antusch, S.; Armstrong, D. E. J.; Balden, M.; Baluc, N.; Barthe, M.-F.; Basuki, W. W.; Battabyal, M.; Becquart, C. S.; Blagoeva, D.; Boldyryeva, H.; Brinkmann, J.; Celino, M.; Ciupinski, L.; Correia, J. B.; De Backer, A.; Domain, C.; Gaganidze, E.; García-Rosales, C.; Gibson, J.; Gilbert, M. R.; Giusepponi, S.; Gludovatz, B.; Greuner, H.; Heinola, K.; Höschen, T.; Hoffmann, A.; Holstein, N.; Koch, F.; Krauss, W.; Li, H.; Lindig, S.; Linke, J.; Linsmeier, Ch.; López-Ruiz, P.; Maier, H.; Matejicek, J.; Mishra, T. P.; Muhammed, M.; Muñoz, A.; Muzyk, M.; Nordlund, K.; Nguyen-Manh, D.; Opschoor, J.; Ordás, N.; Palacios, T.; Pintsuk, G.; Pippan, R.; Reiser, J.; Riesch, J.; Roberts, S. G.; Romaner, L.; Rosiński, M.; Sanchez, M.; Schulmeyer, W.; Traxler, H.; Ureña, A.; van der Laan, J. G.; Veleva, L.; Wahlberg, S.; Walter, M.; Weber, T.; Weitkamp, T.; Wurster, S.; Yar, M. A.; You, J. H.; Zivelonghi, A.

    2013-01-01

    The current magnetic confinement nuclear fusion power reactor concepts going beyond ITER are based on assumptions about the availability of materials with extreme mechanical, heat, and neutron load capacity. In Europe, the development of such structural and armour materials together with the necessary production, machining, and fabrication technologies is pursued within the EFDA long-term fusion materials programme. This paper reviews the progress of work within the programme in the area of tungsten and tungsten alloys. Results, conclusions, and future projections are summarized for each of the programme's main subtopics, which are: (1) fabrication, (2) structural W materials, (3) W armour materials, and (4) materials science and modelling. It gives a detailed overview of the latest results on materials research, fabrication processes, joining options, high heat flux testing, plasticity studies, modelling, and validation experiments.

  16. Recent progress in research on tungsten materials for nuclear fusion applications in Europe

    International Nuclear Information System (INIS)

    Rieth, M.; Dudarev, S.L.; Gonzalez de Vicente, S.M.; Aktaa, J.; Ahlgren, T.; Antusch, S.; Armstrong, D.E.J.; Balden, M.; Baluc, N.; Barthe, M.-F.; Basuki, W.W.; Battabyal, M.; Becquart, C.S.; Blagoeva, D.; Boldyryeva, H.

    2013-01-01

    The current magnetic confinement nuclear fusion power reactor concepts going beyond ITER are based on assumptions about the availability of materials with extreme mechanical, heat, and neutron load capacity. In Europe, the development of such structural and armour materials together with the necessary production, machining, and fabrication technologies is pursued within the EFDA long-term fusion materials programme. This paper reviews the progress of work within the programme in the area of tungsten and tungsten alloys. Results, conclusions, and future projections are summarized for each of the programme’s main subtopics, which are: (1) fabrication, (2) structural W materials, (3) W armour materials, and (4) materials science and modelling. It gives a detailed overview of the latest results on materials research, fabrication processes, joining options, high heat flux testing, plasticity studies, modelling, and validation experiments.

  17. Recent progress in research on tungsten materials for nuclear fusion applications in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Rieth, M., E-mail: Michael.rieth@kit.edu [Karlsruhe Institute of Technology, Institute for Applied Materials, Karlsruhe (Germany); Dudarev, S.L. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Gonzalez de Vicente, S.M. [EFDA-Close Support Unit, Garching (Germany); Aktaa, J. [Karlsruhe Institute of Technology, Institute for Applied Materials, Karlsruhe (Germany); Ahlgren, T. [University of Helsinki, Department of Physics, Helsinki (Finland); Antusch, S. [Karlsruhe Institute of Technology, Institute for Applied Materials, Karlsruhe (Germany); Armstrong, D.E.J. [Department of Materials, University of Oxford (United Kingdom); Balden, M. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Baluc, N. [Centre de Recherches en Physique des Plasmas, CRPP EPFL - Materials, 5232 Villigen/PSI (Switzerland); Barthe, M.-F. [CNRS, UPR3079 CEMHTI, 1D Avenue, de la Recherche Scientifique, 45071 Orleans cedex 2 (France); Universite d' Orleans, Polytech ou Faculte des Sciences, Avenue du Parc Floral, BP 6749, 45067 Orleans cedex 2 (France); Basuki, W.W. [Karlsruhe Institute of Technology, Institute for Applied Materials, Karlsruhe (Germany); Battabyal, M. [Centre de Recherches en Physique des Plasmas, CRPP EPFL - Materials, 5232 Villigen/PSI (Switzerland); Becquart, C.S. [Unite Materiaux et Transformations, UMR 8207, 59655 Villeneuve d' Ascq (France); Blagoeva, D. [NRG, Nuclear Research and consultancy Group, Petten (Netherlands); Boldyryeva, H. [Institute of Plasma Physics, Za Slovankou 3, 18200 Praha (Czech Republic); and others

    2013-01-15

    The current magnetic confinement nuclear fusion power reactor concepts going beyond ITER are based on assumptions about the availability of materials with extreme mechanical, heat, and neutron load capacity. In Europe, the development of such structural and armour materials together with the necessary production, machining, and fabrication technologies is pursued within the EFDA long-term fusion materials programme. This paper reviews the progress of work within the programme in the area of tungsten and tungsten alloys. Results, conclusions, and future projections are summarized for each of the programme's main subtopics, which are: (1) fabrication, (2) structural W materials, (3) W armour materials, and (4) materials science and modelling. It gives a detailed overview of the latest results on materials research, fabrication processes, joining options, high heat flux testing, plasticity studies, modelling, and validation experiments.

  18. Characterization of the Material Microstructure for Reactive Material Design. 3rd Quarterly Progress Report II/2008

    Science.gov (United States)

    2008-08-05

    metallic) materials, which fragment under certain dynamic loading conditions into small particles, which can chemically react with a suitable ambient ...medium, such as shock heated ambient air or hot detonation products. Such materials could be effectively used to devise new or improved weapons with...test is blue. The impacto conditions of the the center of the the opposite surfa reflection of the w Figure 6.1: Example o specimen. Another aspect

  19. Progress report for 1984/85 from the Plutonium Contaminated Materials Working Party

    International Nuclear Information System (INIS)

    Higson, S.G.

    1985-01-01

    The progress report for 1984/5 from the 'Plutonium Contaminated Materials Working Party' is presented. The report is divided into eight main topics, each discussed separately, and include: reduction of arisings, plutonium measurement, sorting and packaging, washing of shredded combustible plutonium contaminated materials (PCM), decommissioning and non-combustible PCM treatment, PCM immobilization, treatment of alpha bearing liquid wastes, and engineering objectives. (U.K.)

  20. Plutonium contaminated materials research programme. Progress Report for 1983/84 from the Plutonium Contaminated Materials Working Party

    International Nuclear Information System (INIS)

    Higson, S.G.

    1984-01-01

    Plutonium contaminated material (PCM) is a generic term applied to a wide variety of materials which have become contaminated by plutonium compounds, by virtue of their use inside the primary containment of fuel cycle plants, but which generally have low beta gamma content. The report falls under the headings: introduction; organisation and role of the PCMWP; management practices; 1983/84 progress report (a) reduction of arisings; (b) plutonium measurement; (c) treatment of solid PCM; (d) treatment of alpha bearing liquid wastes; (e) actinide chemistry; (f) engineering objectives. (U.K.)

  1. Progress report for 1986 from the Plutonium Contaminated Materials Working Party

    International Nuclear Information System (INIS)

    Higson, S.G.

    1987-11-01

    The paper covers progress during 1986 under the joint BNFL/MOD/DoE funded PCM Working Party studying the management, treatment and immobilization of plutonium contaminated materials. Development is reported under each of seven main programme headings including reduction of arisings, Pu measurement, decommissioning and non-combustible PCM treatment, liquid effluent treatment, sorting and packaging, PCM immobilisation and engineering objectives. (author)

  2. Metals and ceramics division materials science program. Aunnual progress report for period ending June 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    McHargue, C.J.

    1979-10-01

    Progress is reported concerning theoretical studies of metals and alloys, deformation and mechanical properties, physical properties and transport phenomena, radiation effects, and engineering materials. During this period emphasis was shifted from support of nuclear technologies to support of nonnuclear energy systems. (FS)

  3. Metals and ceramics division materials science program. Aunnual progress report for period ending June 30, 1979

    International Nuclear Information System (INIS)

    McHargue, C.J.; b.

    1979-10-01

    Progress is reported concerning theoretical studies of metals and alloys, deformation and mechanical properties, physical properties and transport phenomena, radiation effects, and engineering materials. During this period emphasis was shifted from support of nuclear technologies to support of nonnuclear energy systems

  4. Materials project of the Energy Conversion and Utilization Technologies (ECUT) program for Fiscal Year 1983: Annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Morris, L.E.; Jordan, A.; Carpenter, J.A. Jr.

    1987-02-01

    This is the annual technical progress report for fiscal year 1983 of the Materials Project of the US Department of Energy (DOE) Energy Conversion and Utilization Technologies (ECUT) Program. In fiscal year 1983, the ECUT Materials Project conducted research in four technical areas, or ''work elements,'' entitled High Temperature Materials, Lightweight Materials, Materials by Design, and New Assessments and Initiatives. The progress of the various tasks of the work elements is discussed in this report.

  5. [Progress of in vivo study on degradable magnesium alloys application as bone-implant materials].

    Science.gov (United States)

    Qi, Zhengrong; Zhang, Qiang; Yin, Yi; Wang, Yan

    2012-11-01

    To review the progress of in vivo study on degradable magnesium alloys application as bone-implant materials. Recent literature was extensively reviewed and summarized, concerning the in vivo study on degradable magnesium alloys as orthopaedic implants. Magnesium alloys possess a natural ability to degrade via corrosion in vivo, which is promising candidate material for orthopaedic medical device applications. A great progress has been made to improve in vivo performance and integration with bone tissue. However, the degradation mechanism of magnesium-based materials in the physiological environment and long-term effect on body are not available. The modulation of the corrosion rate of magnesium alloys must also be accomplished. Magnesium alloys have the potential to serve as degradable implants for orthopaedic applications, but a great deal of further investigation is still necessary.

  6. BaM/YIG nano-composites: A microwave material for C to U band application

    Directory of Open Access Journals (Sweden)

    Vipul Sharma

    2017-05-01

    Full Text Available Hexaferrites have become important candidates for a variety of microwave and millimeter wave devices due to their large uniaxial magneto-crystalline anisotropy and high saturation magnetization. The goal of the present investigation is to synthesize Barium hexaferrite/Yttrium Iron Garnet (BaFe12O19/Y3Fe5O12: (BaM/YIG Nano-Composites (NCs to be used in broad band microwave frequency range applications, especially as microwave absorber. X-ray diffractometry, Vibrating Sample Magnetometer (VSM, and ferromagnetic resonance (FMR techniques were used to characterize these NCs. Using a Cu coplanar wave guide and a Vector Network Analyzer, broadband (C to U microwave absorption were investigated by placing the bulk sample in flip chip mode. Various mathematical models were employed to fit the experimental data to yield intrinsic and extrinsic damping parameters.

  7. Fusion reactor materials semiannual progress report for period ending September 30, 1990

    International Nuclear Information System (INIS)

    1991-04-01

    This is the ninth in series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following technical progress reports: Alloy Development of Irradiation Performance; Damage Analysis and Fundamental Studies; and Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide

  8. Fusion Reactor Materials semiannual progress report for the period ending March 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-07-01

    This is the twelfth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following progress reports: Alloy Development for Irradiation Performance; Damage Analysis and Fundamental Studies; and Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide.

  9. Fusion reactor materials semiannual progress report for the period ending March 31, 1991

    International Nuclear Information System (INIS)

    1991-07-01

    This is the tenth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following progress reports: alloy development for irradiation performance; damage analysis and fundamental studies; special purpose materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of program participants, and to provide a means of communicating the efforts of materials scientists to the test of the fusion community, both nationally and worldwide

  10. Fusion materials semiannual progress report for the period ending September 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    This is the sixteenth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following Progress reports: Alloy Development for Irradiation Performance; Damage Analysis and Fundamental Studies; and Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide. The individual papers in this paper have been cataloged separately elsewhere.

  11. Fusion reactor materials semiannual progress report for period ending September 30, 1990

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    This is the ninth in series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following technical progress reports: Alloy Development of Irradiation Performance; Damage Analysis and Fundamental Studies; and Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide.

  12. Fusion materials semiannual progress report for the period ending March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    This is the eighteenth in a series of semiannual technical progress reports on fusion materials. This report combines research and development activities which were previously reported separately in the following progress reports: {sm_bullet} Alloy Development for Irradiation Performance. {sm_bullet} Damage Analysis and Fundamental Studies. {sm_bullet} Special Purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide. This report has been compiled and edited under the guidance of A.F. Rowcliffe by Gabrielle Burn, Oak Ridge National Laboratory. Their efforts, and the efforts of the many persons who made technical contributions, are gratefully acknowledged.

  13. Fusion reactor materials semiannual progress report for the period ending March 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1991-07-01

    This is the tenth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following progress reports: alloy development for irradiation performance; damage analysis and fundamental studies; special purpose materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of program participants, and to provide a means of communicating the efforts of materials scientists to the test of the fusion community, both nationally and worldwide.

  14. Recent progress of dopant-free organic hole-transporting materials in perovskite solar cells

    Science.gov (United States)

    Dongxue, Liu; Liu, Yongsheng

    2017-01-01

    Organic-inorganic hybrid perovskite solar cells have undergone especially intense research and transformation over the past seven years due to their enormous progress in conversion efficiencies. In this perspective, we review the latest developments of conventional perovskite solar cells with a main focus on dopant-free organic hole transporting materials (HTMs). Regarding the rapid progress of perovskite solar cells, stability of devices using dopant-free HTMs are also discussed to help readers understand the challenges and opportunities in high performance and stable perovskite solar cells. Project supported by the Scientific Research Starting Foundation for Overseas Introduced Talents of College of Chemistry, Nankai University.

  15. Magnetic fusion energy materials technology program annual progress report for period ending June 30, 1977

    International Nuclear Information System (INIS)

    Scott, J.L.

    1977-09-01

    The objectives of the Magnetic Fusion Energy (MFE) Materials Technology Program, which is described in this report, are to continue to solve the materials problems of the Fusion Energy Division of ORNL and to meet needs of the national MFE program, directed by the ERDA Division of Magnetic Fusion Energy (DMFE). This work is a continuation of the program described in previous annual progress reports. The principal areas of work include radiation effects, compatibility studies, materials studies related to the plasma-materials interaction, materials engineering, radiation behavior of superconducting magnet insulation, and mechanical properties of superconducting composites. The level of effort and schedules are consistent with Logic II of the DMFE Program Plan

  16. Metals and Ceramics Division materials science annual progress report for period ending June 30, 1977

    International Nuclear Information System (INIS)

    McHargue, C.J.

    1977-09-01

    Progress is reported for research programs in the metals and ceramics division of ORNL. In structure of materials, theoretical research, x-ray diffraction studies, studies of erosion of ceramics, preparation and synthesis of high temperature and special service materials, and studies of stabilities of microphases in high-temperature structural materials. Research into deformation and mechanical properties included physical metallurgy, and grain boundary segregation and embrittlement. Physical properties and transport phenomena were studied and included mechanisms of surface and solid state reactions, and properties of superconducting materials. The radiation effects program, directed at understanding the effects of composition and microstructure on the structure and properties of materials irradiated at elevated temperatures, is also described

  17. Metals and Ceramics Division materials science annual progress report for period ending June 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

    McHargue, C.J. (comp.)

    1977-09-01

    Progress is reported for research programs in the metals and ceramics division of ORNL. In structure of materials, theoretical research, x-ray diffraction studies, studies of erosion of ceramics, preparation and synthesis of high temperature and special service materials, and studies of stabilities of microphases in high-temperature structural materials. Research into deformation and mechanical properties included physical metallurgy, and grain boundary segregation and embrittlement. Physical properties and transport phenomena were studied and included mechanisms of surface and solid state reactions, and properties of superconducting materials. The radiation effects program, directed at understanding the effects of composition and microstructure on the structure and properties of materials irradiated at elevated temperatures, is also described. (GHT)

  18. Fusion materials semiannual progress report for the period ending December 31, 1996

    International Nuclear Information System (INIS)

    1997-04-01

    This is the twenty-first in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. This effort forms one element of the materials program being conducted in support of the Fusion Energy Sciences Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The report covers the following topics: vanadium alloys; silicon carbide composite materials; ferritic/martensitic steels; copper alloys and high heat flux materials; austenitic stainless steels; insulating ceramics and optical materials; solid breeding materials; radiation effects, mechanistic studies and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; and irradiation facilities, test matrices, and experimental methods

  19. Development of Coatings for Radar Absorbing Materials at X-band

    Science.gov (United States)

    Kumar, Abhishek; Singh, Samarjit

    2018-03-01

    The present review gives a brief account on some of the technical features of radar absorbing materials (RAMs). The paper has been presented with a concentrated approach towards the material aspects for achieving enhanced radar absorption characteristics for its application as a promising candidate in stealth technology and electromagnetic interference (EMI) minimization problems. The effect of metal particles doping/dispersion in the ferrites and dielectrics has been discussed for obtaining tunable radar absorbing characteristics. A short theoretical overview on the development of absorber materials, implementation of genetic algorithm (GA) in multi-layering and frequency selective surfaces (FSSs) based multi-layer has also been presented for the development of radar absorbing coatings for achieving better absorption augmented with broadband features in order to counter the radar detection systems.

  20. A Duration Prediction Using a Material-Based Progress Management Methodology for Construction Operation Plans

    Directory of Open Access Journals (Sweden)

    Yongho Ko

    2017-04-01

    Full Text Available Precise and accurate prediction models for duration and cost enable contractors to improve their decision making for effective resource management in terms of sustainability in construction. Previous studies have been limited to cost-based estimations, but this study focuses on a material-based progress management method. Cost-based estimations typically used in construction, such as the earned value method, rely on comparing the planned budget with the actual cost. However, accurately planning budgets requires analysis of many factors, such as the financial status of the sectors involved. Furthermore, there is a higher possibility of changes in the budget than in the total amount of material used during construction, which is deduced from the quantity take-off from drawings and specifications. Accordingly, this study proposes a material-based progress management methodology, which was developed using different predictive analysis models (regression, neural network, and auto-regressive moving average as well as datasets on material and labor, which can be extracted from daily work reports from contractors. A case study on actual datasets was conducted, and the results show that the proposed methodology can be efficiently used for progress management in construction.

  1. Recent Progress in First-Principles Methods for Computing the Electronic Structure of Correlated Materials

    Directory of Open Access Journals (Sweden)

    Fredrik Nilsson

    2018-03-01

    Full Text Available Substantial progress has been achieved in the last couple of decades in computing the electronic structure of correlated materials from first principles. This progress has been driven by parallel development in theory and numerical algorithms. Theoretical development in combining ab initio approaches and many-body methods is particularly promising. A crucial role is also played by a systematic method for deriving a low-energy model, which bridges the gap between real and model systems. In this article, an overview is given tracing the development from the LDA+U to the latest progress in combining the G W method and (extended dynamical mean-field theory ( G W +EDMFT. The emphasis is on conceptual and theoretical aspects rather than technical ones.

  2. Application of cathodoluminescence microscopy to recent and past biological materials: a decade of progress

    Science.gov (United States)

    Barbin, Vincent

    2013-06-01

    Cathodoluminescence (CL) microscopy is a powerful technique for studying biominerals. New progress on CL observation of biological materials is discussed especially the Mn2+ incorporation in shells during life and the relationship with environmental and/or diagenetic parameters. The aragonite-calcite transformation temperature during heating is reviewed, for example, in order to trace the chemical alteration of archaeological fired shells. New data are presented for Mn2+ activated luminescence in crystalline vaterite.

  3. Cladding and structural materials semi-annual progress report, January 1975--July 1975

    International Nuclear Information System (INIS)

    Claudson, T.T.

    1975-10-01

    Theoretical and experimental programs are in progress to determine the effects of fast neutron radiation on the mechanical properties and swelling of 3C4 and 316SS cladding and duct materials. Detailed specimen characterization and detailed test conditions are required in order to provide the 2 to 5 percent accuracy of results at 1γ. Preliminary swelling tests show that swelling in stressed assemblies is much larger than in unstressed structural components. Correlation of swelling data from high exposure cladding (11.4 at. percent burnup) agrees with previous data and with the current design equation for 20 percent CW 316 stainless steel. Improved techniques for TEM specimen preparation are described along with recent results on crack propagation. Initial results are given for the effects of aging on Inconel 718 base and weld materials. Compilations of these design values of materials properties have been issued in the form of the Nuclear Systems Materials Handbook

  4. Progress in Research on Lightweight Graphene-based EMI Shielding Materials

    Directory of Open Access Journals (Sweden)

    WANG Chan-yuan

    2016-10-01

    Full Text Available With rapid progresses on the advanced electronic science and technology, electromagnetic irradiations have led to considerable issues, including electromagnetic pollutions, electromagnetic interference and security concerns, in electronics, aeronautics, astronautics, information technology, communication systems and etc. Based on the fundamentals of the electromagnetic interference shielding and general methods for preparing graphene nanosheets, this review involves the recent advances in the electromagnetic interference shielding materials of various applications in four morphologies, which include bulk, lightweight foams, flexible films and those for operation at high temperature. Meanwhile, the major strategical methods and general concept for designing and fabricating graphene-based electromagnetic interference shielding materials have been overviewed, and fundamental issues of electromagnetic interference technology have been further discussed. The perspectives for fabricating novel electromagnetic interference shielding materials, including ultrathin and transparent configuration, and future development have been proposed based on the practical applications, which suggest significant conception for designing next generation lightweight EMI shielding materials.

  5. Progress of research on plasma facing materials in University of Science and Technology Beijing

    International Nuclear Information System (INIS)

    Ge, Chang-Chun; Zhou, Zhang-Jian; Song, Shu-Xiang; Du, Juan; Zhong, Zhi-Hong

    2007-01-01

    In this paper, we report some new progress on plasma facing materials in University of Science and Technology Beijing (USTB), China. They include fabrication of tungsten coating with ultra-fine grain size by atmosphere plasma spraying; fabrication of tungsten with ultra-fine grain size by a newly developed method named as resistance sintering under ultra-high pressure; using the concept of functionally graded materials to join tungsten to copper based heat sink; joining silicon doped carbon to copper by brazing using a Ti based amorphous filler and direct casting

  6. Controlled thermonuclear materials technology program. Annual progress report for period ending June 30, 1975

    International Nuclear Information System (INIS)

    Scott, J.L.

    1975-10-01

    Detailed descriptions are given of research progress in the following areas: (1) microstructure of irradiated 316 stainless steel containing high helium concentrations, (2) temperature and fluence limitations for a type 316 stainless steel CTR first wall, (3) swelling and microstructural changes in irradiated vanadium alloys, (4) mechanical properties of irradiated V-20 wt percent Ti, (5) radiation damage calculations, (6) evaluation of irradiation facilities for CTR materials development, (7) surface studies, compatibility studies, (8) magnet development, (9) EPR design support, and (10) the influence of structural materials on fusion-reactor blanket response. (MOW)

  7. Unsupervised progressive elastic band exercises for frail geriatric inpatients objectively monitored by new exercise-integrated technology

    DEFF Research Database (Denmark)

    Rathleff, Camilla Rams; Bandholm, T.; Spaich, Erika Geraldina

    2017-01-01

    the amount of supervised training, and unsupervised training could possibly supplement supervised training thereby increasing the total exercise dose during admission. A new valid and reliable technology, the BandCizer, objectively measures the exact training dosage performed. The purpose was to investigate...... with the intervention. Results: Four (27%) out of 15 patients completed 33% of the recommended number of sets. For the total sample, the average percent of performed sets was 23% and for those who actually trained (n = 12) 26%. Patients and staff expressed a general positive attitude towards the unsupervised training...... positive attitudes towards the unsupervised training. As even a small training dosage has been shown to improve the physical performance of geriatric inpatients, the proposed intervention might be relevant if the interruptions are decreased in future large-scale trials and if the adherence is increased...

  8. Low-resistant and high transmittance films based on one dimensional metal-dielectric photonic band gap material

    Science.gov (United States)

    Zhao, Ya-li; Li, Xu-feng; Ma, Jiang-jiang; Ma, Fu-Hua; Chen, Zhi-Hui; Wei, Xue-hong

    2017-12-01

    The paper shows the determination of the transmission of one dimensional metal-dielectric photonic band gap materials (1D-MD PBG) theoretically and experimentally. It has been found that the location and bandwidth of transmission can be tailored by initiatively adopting a suitable structure. We proposed a special 1D-MD PBG obtained by magnetron sputtering, in which each layer of metal film is not continuous. These structures have a number of advantages such as high transmittance (55% or better), broad bandwidth (the full width at half of maximum ranges from 400 nm to 780 nm) and high electrical conductivity (the sheet resistance can be lower than 0.98 Ω/square). Meanwhile, it has been also theoretically and experimental indicated that both the light transmittance and electrical conductivity could be improved effectively by using the (pqp)N structure.

  9. Fusion materials semiannual progress report for the period ending December 31, 1997

    International Nuclear Information System (INIS)

    Burn, G.

    1998-03-01

    This is the twenty-third in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. This effort forms one element of the materials program being conducted in support of the Fusion Energy Sciences Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reported separately. The Fusion Materials Program is a national effort involving several national laboratories, universities, and industries. A large fraction of this work, particularly in relation to fission reactor experiments, is carried out collaboratively with their partners in Japan, Russia, and the European Union. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide

  10. Materials and Device Optimization for High Power SiGe HBT Amplifiers at X-Band Frequencies

    Science.gov (United States)

    Mueller, C. H.; Alterovitz, S. A.; Croke, E. T.

    1999-01-01

    The driving force behind SiGe development is the potential for high frequency and high power devices that provide comparable functionality as more expensive semiconductors such as InP and GaAs, but at a much lower cost. Additional advantages are the potential for incorporating SiGe devices onto monolithic Si chips and fabricating entire systems, such as receiver front-ends or RF power amplifiers, on a single chip. The work reported in this paper summarizes the materials and simulation aspects of a much larger project, which will eventually lead to SiGe HBT amplifiers with output powers greater than 1 W and over 35 dB gain at X-band frequencies. To achieve these goals, accurate analysis of the materials properties, especially in the base region, and highly refined amplifier design procedures must be established. In this paper we report the precision that may be obtained using optical ellipsometry to monitor the base and emitter thicknesses and Ge content of the base. We also report the extent of crystalline degradation in state-of-the-art SiGe films with high Ge contents. The objective of this work is to access the materials quality of HBT structures, and then use this data to model how various defects impact device performance, and which defects are most likely to limit high power and/or high frequency performance.

  11. Negative thermal expansion and broad band photoluminescence in a novel material of ZrScMo2VO12.

    Science.gov (United States)

    Ge, Xianghong; Mao, Yanchao; Liu, Xiansheng; Cheng, Yongguang; Yuan, Baohe; Chao, Mingju; Liang, Erjun

    2016-04-21

    In this paper, we present a novel material with the formula of ZrScMo2VO12 for the first time. It was demonstrated that this material exhibits not only excellent negative thermal expansion (NTE) property over a wide temperature range (at least from 150 to 823 K), but also very intense photoluminescence covering the entire visible region. Structure analysis shows that ZrScMo2VO12 has an orthorhombic structure with the space group Pbcn (No. 60) at room temperature. A phase transition from monoclinic to orthorhombic structure between 70 and 90 K is also revealed. The intense white light emission is tentatively attributed to the n- and p-type like co-doping effect which creates not only the donor- and acceptor-like states in the band gap, but also donor-acceptor pairs and even bound exciton complexes. The excellent NTE property integrated with the intense white-light emission implies a potential application of this material in light emitting diode and other photoelectric devices.

  12. Progress in understanding the mechanical behavior of pressure-vessel materials at elevated temperatures

    International Nuclear Information System (INIS)

    Swindeman, R.W.; Brinkman, C.R.

    1981-01-01

    Progress during the 1970's on the production of high-temperature mechanical properties data for pressure vessel materials was reviewed. The direction of the research was toward satisfying new data requirements to implement advances in high-temperature inelastic design methods. To meet these needs, servo-controlled testing machines and high-resolution extensometry were developed to gain more information on the essential behavioral features of high-temperature alloys. The similarities and differences in the mechanical response of various pressure vessel materials were identified. High-temperature pressure vessel materials that have received the most attention included Type 304 stainless steel, Type 316 stainless steel, 2 1/4 Cr-1 Mo steel, alloy 800H, and Hastelloy X

  13. Science of materials. Progress report, July 1, 1977--June 30, 1978

    Energy Technology Data Exchange (ETDEWEB)

    1978-04-01

    Progress is reported in research which includes studies of the deformation, stress corrosion and fracture of alloys and geologic materials with emphasis on hydrogen embrittlement of metals; the mechanism of heat transfer across interfaces; catalytic properties of surfaces; and erosion of surfaces by fluid suspended particles. The structure of liquids, polymers and disordered solids is under investigation with emphasis on ionic conduction, phase transitions and radiation damage. Ferro- and pyroelectric materials with potential for solar energy applications are under development. The study of optical properties includes the mechanism of luminescence and new semiconductor materials for photovoltaic devices. The electronic properties of crystals are the subject of a continued effort to resolve current problems of magnetic behavior and photon-solid interactions. Specific quantum properties of matter are explored with emphasis on superconductivity, diffusion of hydrogen in metals and the properties of solid helium.

  14. Recent progress in theoretical and computational investigations of Li-ion battery materials and electrolytes.

    Science.gov (United States)

    Bhatt, Mahesh Datt; O'Dwyer, Colm

    2015-02-21

    There is an increasing worldwide demand for high energy density batteries. In recent years, rechargeable Li-ion batteries have become important power sources, and their performance gains are driving the adoption of electrical vehicles (EV) as viable alternatives to combustion engines. The exploration of new Li-ion battery materials is an important focus of materials scientists and computational physicists and chemists throughout the world. The practical applications of Li-ion batteries and emerging alternatives may not be limited to portable electronic devices and circumventing hurdles that include range anxiety and safety among others, to their widespread adoption in EV applications in the future requires new electrode materials and a fuller understanding of how the materials and the electrolyte chemistries behave. Since this field is advancing rapidly and attracting an increasing number of researchers, it is crucial to summarise the current progress and the key scientific challenges related to Li-ion batteries from theoretical point of view. Computational prediction of ideal compounds is the focus of several large consortia, and a leading methodology in designing materials and electrolytes optimized for function, including those for Li-ion batteries. In this Perspective, we review the key aspects of Li-ion batteries from theoretical perspectives: the working principles of Li-ion batteries, the cathodes, anodes, and electrolyte solutions that are the current state of the art, and future research directions for advanced Li-ion batteries based on computational materials and electrolyte design.

  15. Review on recent progress of nanostructured anode materials for Li-ion batteries

    KAUST Repository

    Goriparti, Subrahmanyam

    2014-07-01

    This review highlights the recent research advances in active nanostructured anode materials for the next generation of Li-ion batteries (LIBs). In fact, in order to address both energy and power demands of secondary LIBs for future energy storage applications, it is required the development of innovative kinds of electrodes. Nanostructured materials based on carbon, metal/semiconductor, metal oxides and metal phosphides/nitrides/sulfides show a variety of admirable properties for LIBs applications such as high surface area, low diffusion distance, high electrical and ionic conductivity. Therefore, nanosized active materials are extremely promising for bridging the gap towards the realization of the next generation of LIBs with high reversible capacities, increased power capability, long cycling stability and free from safety concerns. In this review, anode materials are classified, depending on their electrochemical reaction with lithium, into three groups: intercalation/de-intercalation, alloy/de-alloy and conversion materials. Furthermore, the effect of nanoscale size and morphology on the electrochemical performance is presented. Synthesis of the nanostructures, lithium battery performance and electrode reaction mechanisms are also discussed. To conclude, the main aim of this review is to provide an organic outline of the wide range of recent research progresses and perspectives on nanosized active anode materials for future LIBs.

  16. Off-axis photonic bands of hexagonal plasma photonic crystal fiber containing elliptical holes with defect of high index material for nonlinear waves by PWE method

    Science.gov (United States)

    Dixit, Achyutesh; Pandey, Praveen Chandra

    2017-05-01

    A novel model of hexagonal photonic crystal fiber (PCF) composed of fluoride-doped silicate and plasma materials for estimating the off-axis band structure has been presented. The well-known plane wave expansion (PWE) method has been adopted for the analysis of band structure. We have observed the influence of intensity of field on photonic band gap (PBG) by creating different types of defect in the holes of the PCF structure for the design of waveguide and narrow-band filter. A dynamic shift in bands and photonic band gaps (PBGs) has been reported and compared with other designs. The PCF containing the defect of high index material in the presence of plasma has been found to be more suitable to control the propagation of photon for nonlinear waves. The PWE calculations have shown that the four off-axis PBGs for the different contribution of plasma holes could exceed by 1.0 normalized frequency or they could compensate within 0.24 normalized frequencies on introducing alternate distribution of high index material like SF57 in the cladding.

  17. Progress toward mutual reciprocal inspections of fissile materials from dismantled nuclear weapons

    International Nuclear Information System (INIS)

    Johnson, M.W.; Gosnell, T.B.

    1995-01-01

    In March 1994, the United States and the Russian Federation announced their intention to conduct mutual reciprocal inspections (MRI) to confirm inventories of fissile materials from dismantled nuclear weapons. Subsequent interactions between the two countries have established the basis for an MRI regime, covering instrumentation, candidate sites for MRI, and protection of information deemed sensitive by the countries. This paper discusses progress made toward MRI, stressing measurement technologies and observables, as well as prospects for MRI implementation. An analysis is presented of observables that might be exploited to provide assurance that the material being measured could have come from a dismantled weapon rather than other sources. Instrumentation to exploit these observables will also be discussed, as will joint US/Russian efforts to demonstrate such instrumentation. Progress toward a so-called ''program of cooperation'' between the two countries in protecting each other's sensitive information will be reviewed. All of these steps are essential components of an eventual comprehensive regime for controlling fissile materials from weapons

  18. Research progress on organic-inorganic halide perovskite materials and solar cells

    Science.gov (United States)

    Ono, Luis K.; Qi, Yabing

    2018-03-01

    Owing to the intensive research efforts across the world since 2009, perovskite solar cell power conversion efficiencies (PCEs) are now comparable or even better than several other photovoltaic (PV) technologies. In this topical review article, we review recent progress in the field of organic-inorganic halide perovskite materials and solar cells. We associate these achievements with the fundamental knowledge gained in the perovskite research. The major recent advances in the fundamental perovskite material and solar cell research are highlighted, including the current efforts in visualizing the dynamical processes (in operando) taking place within a perovskite solar cell under operating conditions. We also discuss the existing technological challenges. Based on a survey of recently published works, we point out that to move the perovskite PV technology forward towards the next step of commercialization, what perovskite PV technology need the most in the coming next few years is not only further PCE enhancements, but also up-scaling, stability, and lead-toxicity.

  19. Year 1 Progress Report Computational Materials and Chemical Sciences Network Administration

    Energy Technology Data Exchange (ETDEWEB)

    Rehr, John J.

    2012-08-02

    This document reports progress on the project “Computational Materials and Chemical Sciences Network Administration,” which is supported by DOE BES Grant DE-FG02-02ER45990 MOD 08. As stated in the original proposal, the primary goal of this project is to carry out the scientific administrative responsibilities for the Computational Materials and Chemical Sciences Network (CMCSN) of the U.S. Department of Energy, Office of Basic Energy Sciences. These responsibilities include organizing meetings, publishing and maintaining CMCSN’s website, publishing a periodic newsletter, writing original material for both the website and the newsletter, maintaining CMCSN documentation, editing scientific documents, as needed, serving as liaison for the entire Network, facilitating information exchange across the network, communicating CMCSN’s success stories to the larger community and numerous other tasks outside the purview of the scientists in the CMCSN. Given the dramatic increase in computational power, advances in computational materials science can have an enormous impact in science and technology. For many of the questions that can be addressed by computation there is a choice of theoretical techniques available, yet often there is no accepted understanding of the relative strengths and effectiveness of the competing approaches. The CMCSN fosters progress in this understanding by providing modest additional funding to research groups which engage in collaborative activities to develop, compare, and test novel computational techniques. Thus, the CMCSN provides the “glue” money which enables different groups to work together, building on their existing programs and expertise while avoiding unnecessary duplication of effort. This includes travel funding, partial postdoc salaries, and funding for periodic scientific meetings. The activities supported by this grant are briefly summarized below.

  20. Modeling Geometry and Progressive Failure of Material Interfaces in Plain Weave Composites

    Science.gov (United States)

    Hsu, Su-Yuen; Cheng, Ron-Bin

    2010-01-01

    A procedure combining a geometrically nonlinear, explicit-dynamics contact analysis, computer aided design techniques, and elasticity-based mesh adjustment is proposed to efficiently generate realistic finite element models for meso-mechanical analysis of progressive failure in textile composites. In the procedure, the geometry of fiber tows is obtained by imposing a fictitious expansion on the tows. Meshes resulting from the procedure are conformal with the computed tow-tow and tow-matrix interfaces but are incongruent at the interfaces. The mesh interfaces are treated as cohesive contact surfaces not only to resolve the incongruence but also to simulate progressive failure. The method is employed to simulate debonding at the material interfaces in a ceramic-matrix plain weave composite with matrix porosity and in a polymeric matrix plain weave composite without matrix porosity, both subject to uniaxial cyclic loading. The numerical results indicate progression of the interfacial damage during every loading and reverse loading event in a constant strain amplitude cyclic process. However, the composites show different patterns of damage advancement.

  1. Progress in materials research and applications of high-Tc Superconductors

    International Nuclear Information System (INIS)

    Tanaka, S.

    1991-01-01

    Research on high-T c superconductivity covers most of the fields of materials science, and therefore, interdisciplinary investigations are necessary by scientists with diverse backgrounds in physics, chemistry, ceramics, metallurgy and so on. At present, after much research on the physical properties of materials, the creation of a theory of high-T c superconductivity is extremely urgent. If a theory can be successfully established, its effects must be very wide and deep. solid state physics may be transformed, and the search for new superconducting materials will be accelerated. Furthermore, many applications will be greatly advanced by understanding the phenomena of high-T c materials, and especially concepts for new electronic devices may be forthcoming. In the past, interactions between science and technology have been very clear. They sometimes resonate with each other and exhibit rapid progress in a very short period and give a big impact on society. The research and developments of high-T c superconductivity will hopefully retrace the brilliant history of the great success of the science and technology of semiconductors in the near future. The author is very optimistic about this

  2. Recent progress in low-voltage cathodoluminescent materials: synthesis, improvement and emission properties.

    Science.gov (United States)

    Li, Guogang; Lin, Jun

    2014-01-01

    Nowadays there are several technologies used for flat panel displays (FPDs) and the development of FPDs with enhanced energy efficiency and improved display quality is strongly required. Field emission displays (FEDs) have been considered as one of the most promising next generation flat panel display technologies due to their excellent display performance and low energy consumption. For the development of FEDs, phosphors are irreplaceable components. In the past decade, the study of highly efficient low-voltage cathodoluminescent materials, namely FED phosphors, has become the focus of enhancing energy efficiency and realizing high-quality displays. This review summaries the recent progress in the chemical synthesis and improvement of novel, rare-earth and transition metal ions activated inorganic cathodoluminescent materials in powder and thin film forms. The discussion is focused on the modification of morphology, size, surface, composition and conductivity of phosphors and the corresponding effects on their cathodoluminescent properties. Special emphases are given to the selection of host and luminescent centers, the adjustment of emission colors through doping concentration optimization, energy transfer and mono- or co-doping activator ions, the improvement of chromaticity, color stability and color gamut as well as the saturation behavior and the degradation behavior of phosphors under the excitation of a low-voltage electron beam. Finally, the research prospects and future directions of FED phosphors are discussed with recommendations to facilitate the further study of new and highly efficient low-voltage cathodoluminescent materials.

  3. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  4. Evaluation of porewater chemistry in the buffer material for the second progress report H12

    International Nuclear Information System (INIS)

    Oda, Chie; Shibata, Masahiro; Yui, Mikazu

    1999-09-01

    In the safety assessment for geological disposal of high-level radioactive wastes (HLW), porewater chemistry in buffer materials is used to estimate migration of radionuclides and corrosion of overpack materials. For the reference case in the second progress report on research and development for HLW disposal in Japan, entitled H12, porewater chemistry was evaluated by using a chemical model based on an experimental work by Oda and Shibata (1999) under the assumption of a thermodynamic system of groundwater with bentonite and corrosion products of carbon-steel overpack. This report provides the scientific information basis for the porewater chemistry evaluation, and describes the possible variations in porewater composition affected by following factors: - variations in groundwater composition relevant to the alternative geological environments cases and the perturbation scenario, and supplementary variations in groundwater composition. - model/data uncertainties associated with insufficient understanding of important processes with respect to the time-dependent behavior of a geological disposal system: in particular, how the surface reaction of smectite changes with time, how the impurities of bentonite affect porewater, and how the reactions like redox equilibria, kinetics of dissolution of accessory minerals in bentonite and precipitation of secondary minerals (including corrosion products of overpack materials) should be handled in the porewater calculations. - uncertainties of thermodynamic data of the geochemical elements. The results of calculation indicated that porewaters in the buffer material, as far as calcite is not exhausted, may vary within the range of pH from 6 to 11. It was found that important factors on the variations in porewater composition were the change of surface reactions of smectite with time, the degree of soluble impurities dissolution/dispersion and the amount of iron being supplied into the buffer region by corrosion of the overpack

  5. Progress in the activities on prevention and combating of illicit trafficking of nuclear material in Lithuania

    International Nuclear Information System (INIS)

    Kurselis, S.; Stadalnikas, A.

    2001-01-01

    Full text: The paper gives a general overview of the progress which has been made in the activities on prevention and combating of illicit trafficking of nuclear material in Lithuania. It describes the measures which were taken to strengthen nuclear material accounting and control and physical protection. The current status of the national legislation and the functions of institutions involved in control of nuclear material and combating of illicit trafficking are discussed. Lithuania, similar to many countries, did not avoid a new type of a crime - smuggling of nuclear materials - which was observed in the 1990's. The most serious case in Lithuania happened in 1993 when fresh fuel assembly was stolen from Ignalina NPP. This assembly contains approximately 124 kg of UO 2 (enrichment 2%). 100 kg of the pellets from this assembly was found later in several pieces at different places. This case served as a strong stimulus to strengthen prevention measures of Illicit trafficking. The legal basis was created and governmental institutions were obliged with special duties related with nuclear material. The laws and regulations set the order for the shipment and handling of nuclear material. The penalties for violation of these laws and regulations specified in Penal Code and Administrative Code were made stricter. The State system of accounting for and control of nuclear material (SSAC) is a very important element in prevention of the illicit trafficking. The Regulations of Accounting for and Control of Nuclear Material at Nuclear Facilities and LOFs was issued by the State Nuclear Power Safety Inspectorate (VATESI) on 10 December 1997 following the provisions of the Law on Nuclear Energy. Lithuania extended its international obligations by ratifying the Protocol Additional to the Safeguards Agreement (entered into force on 5 July 2000). The fully computerized nuclear material accountancy system was created at Ignalina NPP. The system gives the possibility to find the

  6. Investigation of electronic band structure and charge transfer mechanism of oxidized three-dimensional graphene as metal-free anodes material for dye sensitized solar cell application

    Science.gov (United States)

    Loeblein, Manuela; Bruno, Annalisa; Loh, G. C.; Bolker, Asaf; Saguy, Cecile; Antila, Liisa; Tsang, Siu Hon; Teo, Edwin Hang Tong

    2017-10-01

    Dye-sensitized solar cells (DSSCs) offer an optimal trade-off between conversion-efficiency and low-cost fabrication. However, since all its electrodes need to fulfill stringent work-function requirements, its materials have remained unchanged since DSSC's first report early-90s. Here we describe a new material, oxidized-three-dimensional-graphene (o-3D-C), with a band gap of 0.2 eV and suitable electronic band-structure as alternative metal-free material for DSSCs-anodes. o-3D-C/dye-complex has a strong chemical bonding via carboxylic-group chemisorption with full saturation after 12 sec at capacity of ∼450 mg/g (600x faster and 7x higher than optimized metal surfaces). Furthermore, fluorescence quenching of life-time by 28-35% was measured demonstrating charge-transfer from dye to o-3D-C.

  7. Propulsion System Materials Program semiannual progress report for April 1995 through September 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    Significant accomplishments in fabricating ceramic components for the DOE, NASA, and DOD advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. These programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and data base and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. An assessment of needs was completed, and a 5-year program plan was developed with extensive input from private industry. During the course of the Propulsion System Materials Program, remarkable progress has been made in the development of reliable structural ceramics. However, further work is needed to reduce the cost of ceramics to facilitate their commercial introduction, especially in the highly cost-sensitive automotive market. To this end, the direction of the Propulsion System Materials Program is now shifting toward reducing the cost of ceramics to facilitate commercial introduction of ceramic components for near-term engine applications. In response to extensive input from industry, the plan is to extend the engine types which were previously supported to include near-term (5--10 years) applications in conventional automobile and diesel truck engines. To facilitate the rapid transfer of this technology to US industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities. A systematic approach to reducing the cost of components is envisioned. The work elements are as follows: economic cost modeling, ceramic machining, powder synthesis, alternative forming and densification processes, yield improvement, system design studies, standards development, low-expansion ceramics, and testing and data base development.

  8. Research progress of perovskite materials in photocatalysis- and photovoltaics-related energy conversion and environmental treatment.

    Science.gov (United States)

    Wang, Wei; Tadé, Moses O; Shao, Zongping

    2015-08-07

    Meeting the growing global energy demand is one of the important challenges of the 21st century. Currently over 80% of the world's energy requirements are supplied by the combustion of fossil fuels, which promotes global warming and has deleterious effects on our environment. Moreover, fossil fuels are non-renewable energy and will eventually be exhausted due to the high consumption rate. A new type of alternative energy that is clean, renewable and inexpensive is urgently needed. Several candidates are currently available such as hydraulic power, wind force and nuclear power. Solar energy is particularly attractive because it is essentially clean and inexhaustible. A year's worth of sunlight would provide more than 100 times the energy of the world's entire known fossil fuel reserves. Photocatalysis and photovoltaics are two of the most important routes for the utilization of solar energy. However, environmental protection is also critical to realize a sustainable future, and water pollution is a serious problem of current society. Photocatalysis is also an essential route for the degradation of organic dyes in wastewater. A type of compound with the defined structure of perovskite (ABX3) was observed to play important roles in photocatalysis and photovoltaics. These materials can be used as photocatalysts for water splitting reaction for hydrogen production and photo-degradation of organic dyes in wastewater as well as for photoanodes in dye-sensitized solar cells and light absorbers in perovskite-based solar cells for electricity generation. In this review paper, the recent progress of perovskites for applications in these fields is comprehensively summarized. A description of the basic principles of the water splitting reaction, photo-degradation of organic dyes and solar cells as well as the requirements for efficient photocatalysts is first provided. Then, emphasis is placed on the designation and strategies for perovskite catalysts to improve their

  9. The Role of the Absorption in the Stop Band Tuning of Opals and Inverse Opals Through Coating of Semiconductor Materials

    Science.gov (United States)

    Manzanares-Martinez, Jesus

    2005-03-01

    In this work we report on the modeling of the optical properties of semiconductor in-filled opals and inverse opals for the visible and near infrared spectral region. The crucial influence of the absorption is theoretically investigated by using the three dimensional Transfer Matrix Method (TMM). Fine-tuning of the stop band positioning is achieved with increasing semiconductor infiltration. The red shift of the stop band can be explained by Bragg's law. However, the optical properties depend strongly on the value of the absorption that is directly related to the imaginary part of the Dielectric Constant (DC). We use a realistic model of the DC for a specific semiconductor (InSb) that takes into account the phononic contributions, intrinsic electron and hole densities. By positioning the stop band in the region of the smaller value of the imaginary part of the DC we optimize the value of the lattice constant in order to optimize tuning of the stop band with fewer losses. We also study the influence of absorption in the Fabry-Perot oscillations and in the higher energy stop bands. This work is motivated by new experimental results that show that absorption in 3D structures can be the limiting factor to obtain a useful structure for tuning.

  10. Recent progress in material technology on RE-Ba-Cu-O bulk superconductors

    International Nuclear Information System (INIS)

    Teshima, Hidekazu; Morita, Mitsuru

    2011-01-01

    The current status of large-grained RE-Ba-Cu-O (RE: Y or rare earth elements) bulk superconductors with excellent superconducting properties is described. Gd-Ba-Cu-O bulk superconductors can trap a very high magnetic field even if they are melt-processed in air. Although the electromagnetic force caused by the trapped field is larger for a larger sample and may break the sample, a large sample of Gd-Ba-Cu-O 46 mm in diameter has the potential of trapped magnetic fields greater than 10 T at around 40 K. In addition, single-grained bulk superconductors as large as 150 mm can be obtained using the RE compositional gradient method. Dy-Ba-Cu-O is an ideal material for current leads because it has low thermal conductivity and high critical current density at 77 K in high magnetic fields. Eu-Ba-Cu-O has low magnetic permeability, and is therefore suitable for bulk NMR applications. Progress in machining technology has made possible various bulk superconductors with complicated shapes such as coils, leading to small and strong electromagnets by stacking several coil-shaped bulk superconductors together. (author)

  11. QUARTERLY PROGRESS REPORT JANUARY, FEBRUARY, MARCH, 1968 REACTOR FUELS AND MATERIALS DEVELOPMENT PROGRAMS FOR FUELS AND MATERIALS BRANCH OF USAEC DIVISION OF REACTOR DEVELOPMENT AND TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Cadwell, J. J.; de Halas, D. R.; Nightingale, R. E.; Worlton, D. C.

    1968-06-01

    Progress is reported in these areas: nuclear graphite; fuel development for gas-cooled reactors; HTGR graphite studies; nuclear ceramics; fast-reactor nitrides research; non-destructive testing; metallic fuels; basic swelling studies; ATR gas and water loop operation and maintenance; reactor fuels and materials; fast reactor dosimetry and damage analysis; and irradiation damage to reactor metals.

  12. Progressively expanded neural network for automatic material identification in hyperspectral imagery

    Science.gov (United States)

    Paheding, Sidike

    The science of hyperspectral remote sensing focuses on the exploitation of the spectral signatures of various materials to enhance capabilities including object detection, recognition, and material characterization. Hyperspectral imagery (HSI) has been extensively used for object detection and identification applications since it provides plenty of spectral information to uniquely identify materials by their reflectance spectra. HSI-based object detection algorithms can be generally classified into stochastic and deterministic approaches. Deterministic approaches are comparatively simple to apply since it is usually based on direct spectral similarity such as spectral angles or spectral correlation. In contrast, stochastic algorithms require statistical modeling and estimation for target class and non-target class. Over the decades, many single class object detection methods have been proposed in the literature, however, deterministic multiclass object detection in HSI has not been explored. In this work, we propose a deterministic multiclass object detection scheme, named class-associative spectral fringe-adjusted joint transform correlation. Human brain is capable of simultaneously processing high volumes of multi-modal data received every second of the day. In contrast, a machine sees input data simply as random binary numbers. Although machines are computationally efficient, they are inferior when comes to data abstraction and interpretation. Thus, mimicking the learning strength of human brain has been current trend in artificial intelligence. In this work, we present a biological inspired neural network, named progressively expanded neural network (PEN Net), based on nonlinear transformation of input neurons to a feature space for better pattern differentiation. In PEN Net, discrete fixed excitations are disassembled and scattered in the feature space as a nonlinear line. Each disassembled element on the line corresponds to a pattern with similar features

  13. [Theoretical studies of dynamics and correlations in heavy electron materials:]: Progress report, August 15, 1987-August 15, 1988

    International Nuclear Information System (INIS)

    1988-01-01

    This paper discusses progress in heavy electron research and high temperature superconductivity research. Particular topics discussed are: quadrupolar Kondo effect; coherence in the Anderson Lattice; Hall effect in heavy electron systems, suppression of supeconductivity by disorder in strongly correlated electronic materials; and charge transfer mechanisms for high temperature superconductivity

  14. Advanced Researech and Technology Development fossil energy materials program: Semiannual progress report for the period ending September 30, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The objective of the ARandTD Fossil Energy Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. The ORNL Fossil Energy Materials Program Office compiles and issues this combined semiannual progress report from camera-ready copies submitted by each of the participating subcontractor organizations. This report of activities on the program is organized in accordance with a work breakdown structure in which projects are organized according to materials research thrust areas. These areas are (1) Structural Ceramics, (2) Alloy Development and Mechanical Properties, (3) Corrosion and Erosion of Alloys, and (4) Assessments and Technology Transfer. Individual projects are processed separately for the data bases.

  15. Fourth annual progress report on special-purpose materials for magnetically confined fusion reactors

    International Nuclear Information System (INIS)

    1982-08-01

    The scope of Special Purpose Materials covers fusion reactor materials problems other than the first-wall and blanket structural materials, which are under the purview of the ADIP, DAFS, and PMI task groups. Components that are considered as special purpose materials include breeding materials, coolants, neutron multipliers, barriers for tritium control, materials for compression and OH coils and waveguides, graphite and SiC, heat-sink materials, ceramics, and materials for high-field (>10-T) superconducting magnets. The Task Group on Special Purpose Materials has limited its concern to crucial and generic materials problems that must be resolved if magnetic-fusion devices are to succeed. Important areas specifically excluded include low-field (8-T) superconductors, fuels for hybrids, and materials for inertial-confinement devices. These areas may be added in the future when funding permits

  16. Advanced research and technology development fossil energy materials program. Quarterly progress report for the period ending September 30, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, R.A. (comp.)

    1981-12-01

    This is the fourth combined quarterly progress report for those projects that are part of the Advanced Research and Technology Development Fossil Energy Materials Program. The objective is to conduct a program of research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. Work performed on the program generally falls into the Applied Research and Exploratory Development categories as defined in the DOE Technology Base Review, although basic research and engineering development are also conducted. A substantial portion of the work on the AR and TD Fossil Energy Materials Program is performed by participating cntractor organizations. All subcontractor work is monitored by Program staff members at ORNL and Argonne National Laboratory. This report is organized in accordance with a work breakdown structure defined in the AR and TD Fossil Energy Materials Program Plan for FY 1981 in which projects are organized according to fossil energy technologies. We hope this series of AR and TD Fossil Energy Materials Program quarterly progress reports will aid in the dissemination of information developed on the program.

  17. Discovery of high-performance low-cost n-type Mg3Sb2-based thermoelectric materials with multi-valley conduction bands

    DEFF Research Database (Denmark)

    Zhang, Jiawei; Song, Lirong; Pedersen, Steffen Hindborg

    2017-01-01

    -cost n-type material, Te-doped Mg3Sb1.5Bi0.5, that exhibits a very high figure of merit zT ranging from 0.56 to 1.65 at 300-725 K. Using combined theoretical prediction and experimental validation, we show that the high thermoelectric performance originates from the significantly enhanced power factor...... because of the multi-valley band behaviour dominated by a unique near-edge conduction band with a sixfold valley degeneracy. This makes Te-doped Mg3Sb1.5Bi0.5 a promising candidate for the low- and intermediate-temperature thermoelectric applications....

  18. Photonic band structure computations.

    Science.gov (United States)

    Hermann, D; Frank, M; Busch, K; Wolfle, P

    2001-01-29

    We introduce a novel algorithm for band structure computations based on multigrid methods. In addition, we demonstrate how the results of these band structure calculations may be used to compute group velocities and effective photon masses. The results are of direct relevance to studies of pulse propagation in such materials.

  19. Analytical methods for fissionable materials in the nuclear fuel cycle. Progress report, July 1, 1975--September 30, 1976

    International Nuclear Information System (INIS)

    Waterbury, G.R.

    1976-12-01

    Progress continued on development of dissolution techniques for difficult-to-dissolve nuclear materials, development of methods and automated instruments for determinations of plutonium and uranium, preparation of plutonium-containing materials for the Safeguards Analytical Laboratory Evaluation (SALE) program, analysis of SALE uranium materials, and measurement of plutonium isotope half-lives. Gas-solid reactions at elevated temperatures using reactive gases such as chlorine continue to show promise for separating uranium from refractory materials. An extensive study of nonaqueous solvents for the dissolution of refractory materials is in progress. An extraction-separation procedure, highly specific for microgram amounts of uranium, has been developed, and its adaptation to the Los Alamos Scientific Laboratory (LASL) automated spectrophotometer is being evaluated. Development of an electrometric analysis method for plutonium is nearing completion, and design of an automated instrument using the method has been started. Batches of plutonium oxide and mixed uranium--plutonium, intended for issue as Secondary Reference and Calibration Test Materials, are being recharacterized for assay and isotopic contents. The half-life of 239 Pu has been determined by isotope-dilution mass-spectrometric measurement of 235 U grow-in as a function of time

  20. Analytical methods for fissionable materials in the nuclear fuel cycle. Progress report, July 1, 1975--September 30, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Waterbury, G.R. (comp.)

    1976-12-01

    Progress continued on development of dissolution techniques for difficult-to-dissolve nuclear materials, development of methods and automated instruments for determinations of plutonium and uranium, preparation of plutonium-containing materials for the Safeguards Analytical Laboratory Evaluation (SALE) program, analysis of SALE uranium materials, and measurement of plutonium isotope half-lives. Gas-solid reactions at elevated temperatures using reactive gases such as chlorine continue to show promise for separating uranium from refractory materials. An extensive study of nonaqueous solvents for the dissolution of refractory materials is in progress. An extraction-separation procedure, highly specific for microgram amounts of uranium, has been developed, and its adaptation to the Los Alamos Scientific Laboratory (LASL) automated spectrophotometer is being evaluated. Development of an electrometric analysis method for plutonium is nearing completion, and design of an automated instrument using the method has been started. Batches of plutonium oxide and mixed uranium--plutonium, intended for issue as Secondary Reference and Calibration Test Materials, are being recharacterized for assay and isotopic contents. The half-life of /sup 239/Pu has been determined by isotope-dilution mass-spectrometric measurement of /sup 235/U grow-in as a function of time.

  1. Theory of non-Markovian decay of a cascade atom in high-Q cavities and photonic band gap materials

    International Nuclear Information System (INIS)

    Garraway, B M; Dalton, B J

    2006-01-01

    The dynamics of a three-level atom in a cascade configuration with both transitions coupled to a single structured reservoir of quantized field modes is treated using Laplace transform methods applied to the coupled amplitude equations. Results are also obtained from master equations by two different approaches, that is, involving either pseudomodes or quasimodes. Two different types of reservoir are considered, namely a high-Q cavity and a photonic band gap system, in which the respective reservoir structure functions involve Lorentzians. Non-resonant transitions are included in the model. In all cases non-Markovian behaviour for the atomic system can be found, such as oscillatory decay for the high-Q cavity case and population trapping for the photonic band gap case. In the master equation approaches, the atomic system is augmented by a small number of pseudomodes or quasimodes, which in the quasimode approach themselves undergo Markovian relaxation into a flat reservoir of continuum quasimodes. Results from these methods are found to be identical to those from the Laplace transform method including two-photon excitation of the reservoir with both emitting sequences. This shows that complicated non-Markovian decays of an atomic system into structured EM field reservoirs can be described by Markovian models for the atomic system coupled to a small number of pseudomodes or quasimodes

  2. New Material Transistor with Record-High Field-Effect Mobility among Wide-Band-Gap Semiconductors.

    Science.gov (United States)

    Shih, Cheng Wei; Chin, Albert

    2016-08-03

    At an ultrathin 5 nm, we report a new high-mobility tin oxide (SnO2) metal-oxide-semiconductor field-effect transistor (MOSFET) exhibiting extremely high field-effect mobility values of 279 and 255 cm(2)/V-s at 145 and 205 °C, respectively. These values are the highest reported mobility values among all wide-band-gap semiconductors of GaN, SiC, and metal-oxide MOSFETs, and they also exceed those of silicon devices at the aforementioned elevated temperatures. For the first time among existing semiconductor transistors, a new device physical phenomenon of a higher mobility value was measured at 45-205 °C than at 25 °C, which is due to the lower optical phonon scattering by the large SnO2 phonon energy. Moreover, the high on-current/off-current of 4 × 10(6) and the positive threshold voltage of 0.14 V at 25 °C are significantly better than those of a graphene transistor. This wide-band-gap SnO2 MOSFET exhibits high mobility in a 25-205 °C temperature range, a wide operating voltage of 1.5-20 V, and the ability to form on an amorphous substrate, rendering it an ideal candidate for multifunctional low-power integrated circuit (IC), display, and brain-mimicking three-dimensional IC applications.

  3. Special-purpose materials for magnetically confined fusion reactors. Third annual progress report

    International Nuclear Information System (INIS)

    1981-11-01

    The scope of Special Purpose Materials covers fusion reactor materials problems other than the first-wall and blanket structural materials, which are under the purview of the ADIP, DAFS, and PMI task groups. Components that are considered as special purpose materials include breeding materials, coolants, neutron multipliers, barriers for tritium control, materials for compression and OH coils and waveguides, graphite and SiC, heat-sink materials, ceramics, and materials for high-field (>10-T) superconducting magnets. It is recognized that there will be numerous materials problems that will arise during the design and construction of large magnetic-fusion energy devices such as the Engineering Test Facility (ETF) and Demonstration Reactor (DEMO). Most of these problems will be specific to a particular design or project and are the responsibility of the project, not the Materials and Radiation Effects Branch. Consequently, the Task Group on Special Purpose Materials has limited its concern to crucial and generic materials problems that must be resolved if magnetic-fusion devices are to succeed. Important areas specifically excluded include low-field (8-T) superconductors, fuels for hybrids, and materials for inertial-confinement devices. These areas may be added in the future when funding permits

  4. Progress report, Chemistry and Materials Division, October 1 to December 31, 1976

    International Nuclear Information System (INIS)

    1977-01-01

    A summary is given of research largely centering around radiation effects on materials, radiation and analytical chemistry, surface studies, and materials science, esp. zirconium base alloys and their problems and properties in nuclear service. (E.C.B.)

  5. Technical Progress Report for "Optical and Electrical Properties of III-Nitrides and Related Materials"

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Hongxing

    2008-10-31

    Investigations have been conducted focused on the fundamental material properties of AIN and high AI-content AIGaN alloys and further developed MOCVD growth technologies for obtaining these materials with improved crystalline quality and conductivities.

  6. A brief summary of the progress on the EFDA tungsten materials program

    Czech Academy of Sciences Publication Activity Database

    Rieth, M.; Dudarev, S.L.; Gonzalez de Vicente, S.M.; Aktaa, J.; Ahlgren, T.; Antusch, S.; Armstrong, D.E.J.; Balden, M.; Baluc, N.; Barthe, M.-F.; Basuki, W.W.; Battabyal, M.; Becquart, C.S.; Blagoeva, D.; Boldyryeva, Hanna; Brinkmann, J.; Celino, M.; Ciupinski, L.; Correia, J.B.; De Backer, A.; Domain, C.; Gaganidze, E.; García-Rosales, C.; Gibson, J.; Gilbert, M.R.; Giusepponi, S.; Gludovatz, B.; Greuner, H.; Heinola, K.; Höschen, T.; Hoffmann, A.; Holstein, N.; Koch, F.; Krauss, W.; Li, H.; Lindig, S.; Linke, J.; Linsmeier, Ch.; López-Ruiz, P.; Maier, H.; Matějíček, Jiří; Mishra, T.P.; Muhammed, M.; Munoz, A.; Muzyk, M.; Nordlund, K.; Nguyen-Manh, D.; Opschoor, J.; Ordás, N.; Palacios, T.; Pintsuk, G.; Pippan, R.; Reiser, J.; Riesch, J.; Roberts, S. G.; Romaner, L.; Rosiński, M.; Sanchez, M.; Schulmeyer, W.; Traxler, H.; Urena, A.; van der Laan, J.G.; Veleva, L.; Wahlberg, S.; Walter, M.; Weber, T.; Weitkamp, T.; Wurster, S.; Yar, M.A.; You, J.H.; Zivelonghi, A.

    2013-01-01

    Roč. 442, 1-3 (2013), S173-S180 ISSN 0022-3115. [Fifteenth International Conference on Fusion Reactor Materials. Charleston, South Carolina, 16.10.2011-22.10.2011] Institutional support: RVO:61389021 Keywords : tungsten * joining * composites * graded materials * fusion materials Subject RIV: JI - Composite Materials Impact factor: 2.016, year: 2013 http://dx.doi.org/10.1016/j.jnucmat.2013.03.062

  7. University of Illinois at Urbana-Champaign, Materials Research Laboratory progress report for FY 1991

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    The Materials Research Laboratory at the University of Illinois is an interdisciplinary laboratory operated in the College of Engineering. Its focus is the science of materials and it supports research in the areas of condensed matter physics, solid state chemistry, and materials science. This report addresses topics such as: an MRL overview; budget; general programmatic and institutional issues; new programs; research summaries for metallurgy, ceramics, solid state physics, and materials chemistry.

  8. University of Illinois at Urbana-Champaign, Materials Research Laboratory progress report for FY 1991

    International Nuclear Information System (INIS)

    1991-10-01

    The Materials Research Laboratory at the University of Illinois is an interdisciplinary laboratory operated in the College of Engineering. Its focus is the science of materials and it supports research in the areas of condensed matter physics, solid state chemistry, and materials science. This report addresses topics such as: an MRL overview; budget; general programmatic and institutional issues; new programs; research summaries for metallurgy, ceramics, solid state physics, and materials chemistry

  9. Materials testing and requirements for the ERDA nuclear-powered artificial heart. Technical progress report, July 15, 1974--May 1, 1975

    International Nuclear Information System (INIS)

    Andrade, J.D.; Coleman, D.L.; Leigh, A.; Hufferd, W.L.

    1975-01-01

    Progress on the materials research and development effort for the ERDA-sponsored nuclear-powered artificial heart program is presented. Progress made during the first three years on hydrogel grafting and biological studies is summarized. Progress during the fourth year on studies of implanted artificial hearts, development of albumin surfaces, and in vitro mechanical studies is presented. (U.S.)

  10. Fusion reactor materials: Semiannual progress report for the period ending March 31, 1988

    International Nuclear Information System (INIS)

    1988-08-01

    This report contains papers on thermonuclear reactor materials. The general categories of these papers are: irradiation facilities, test matrices, and experimental methods; dosimetry, damage parameters and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; development of structural alloys; solid breeding materials; ceramics; and radiation effects. Selected papers have been processed for inclusion in the energy database

  11. Fusion Reactor Materials semiannual progress report for period ending September 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1992-04-01

    This report contains papers on topic in the following areas of thermonuclear reactor materials: irradiation facilities, test matrices, and experimental methods; dosimetry, damage parameters and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials and beryllium; and ceramics. These paper have been index separately elsewhere. (LSP).

  12. Fusion reactor materials semiannual progress report for the period ending September 30, 1988

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1989-04-01

    This paper discusses the following topics on fusion reactor materials: irradiation, facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials; and ceramics.

  13. Fusion reactor materials: Semiannual progress report for the period ending March 31, 1988

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1988-08-01

    This report contains papers on thermonuclear reactor materials. The general categories of these papers are: irradiation facilities, test matrices, and experimental methods; dosimetry, damage parameters and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; development of structural alloys; solid breeding materials; ceramics; and radiation effects. Selected papers have been processed for inclusion in the energy database. (LSP)

  14. Performance of dual-band short- or mid-wavelength infrared photodetectors based on InGaAsSb bulk materials and InAs/GaSb superlattices

    International Nuclear Information System (INIS)

    Sun Yao-yao; Lv Yue-xi; Han Xi; Guo Chun-yan; Jiang Zhi; Hao Hong-yue; Jiang Dong-wei; Wang Guo-wei; Xu Ying-qiang; Niu Zhi-chuan

    2017-01-01

    In this paper, we demonstrate bias-selectable dual-band short- or mid-wavelength infrared photodetectors based on In 0.24 Ga 0.76 As 0.21 Sb 0.79 bulk materials and InAs/GaSb type-II superlattices with cutoff wavelengths of 2.2 μm and 3.6 μm, respectively. At 200 K, the short-wave channel exhibits a peak quantum efficiency of 42% and a dark current density of 5.93 × 10 −5 A/cm 2 at 500 mV, thereby providing a detectivity of 1.55 × 10 11 cm⋅Hz 1/2 /W. The mid-wave channel exhibits a peak quantum efficiency of 31% and a dark current density of 1.22 × 10 −3 A/cm 2 at −300 mV, thereby resulting in a detectivity of 2.71 × 10 10 cm⋅Hz 1/2 /W. Moreover, we discuss the band alignment and spectral cross-talk of the dual-band n-i-p-p-i-n structure. (paper)

  15. Fusion reactor materials: Semiannual progress report for period ending September 30, 1986

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1987-09-01

    These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The major areas of concern covered in this report are irradiation facilities, test matrices, and experimental methods; dosimetry, damage parameters and activation calculations; materials engineering and design requirements; radiation effects; development of structural alloys; solid breeding materials; ceramics and superconducting magnet materials. There are 61 reports cataloged separately. (LSP)

  16. Materials to deliver the promise of fusion power - progress and challenges

    International Nuclear Information System (INIS)

    Bloom, E.E.; Zinkle, S.J.; Wiffen, F.W.

    2004-01-01

    High-performance reduced-activation materials are crucial for fulfillment of the promise of fusion to provide safe, economical, and environmentally acceptable energy. Three reduced activation structural materials have emerged as promising candidates, based on 8-9Cr ferritic/martensitic steels, V-Cr-Ti alloys, and SiC/SiC composites. Due to advances in understanding how to control and engineer the nanoscale phase stability required for harsh neutron irradiation environments, these reduced activation materials have unirradiated properties that are superior to commercially available analogs. Perhaps the most important accomplishment to date from fusion materials research is the radiation effects knowledge base. Models of radiation effects and supporting experiments highlight the critical role of helium production on the microstructural stability and lifetime of irradiated materials. The proposed International Fusion Materials Irradiation Facility (IFMIF) would fill a critical need for fusion materials development

  17. Dirac Cones in Graphene, Interlayer Interaction in Layered Materials, and the Band Gap in MoS2

    Directory of Open Access Journals (Sweden)

    Ivan N. Yakovkin

    2016-11-01

    Full Text Available The 2D outlook of graphene and similar layers has initiated a number of theoretical considerations of electronic structure that are both interesting and exciting, but applying these ideas to real layered systems, in terms of a model 2D system, must be done with extreme care. In the present review, we will discuss the applicability of the 2D concept with examples of peculiarities of electronic structures and interactions in particular layered systems: (i Dirac points and cones in graphene; (ii van der Waals interaction between MoS2 monolayers; and (iii the issue of a 2D screening in estimates of the band gap for MoS2 monolayers.

  18. AR and TD Fossil Energy Materials Program. Quarterly progress report for the period ending December 31, 1981

    Energy Technology Data Exchange (ETDEWEB)

    1982-04-01

    The ORNL Fossil Energy Materials Program Office compiles and issues this combined quarterly progress report from camera-ready copies submitted by each of the participating subcontractor organizations. This report of activities on the program is organized in accordance with a work breakdown structure defined in the AR and TD Fossil Energy Materials Program Plan for FY 1982-1986 in which projects are organized according to fossil energy technologies. This report is divided into parts and chapters with each part describing projects related to a particular fossil energy technology. Chapters within a part provide details of the various projects associated with that technology. We hope this series of AR and TD Fossil Energy Materials Program quarterly progress reports will aid in the dissemination of information developed on the program. Plans for the program will be issued annually. A draft of the program plan for FY 1982 to 1986 has been prepared and is in the review process. The implementation of these plans will be reflected by these quarterly progress reports, and this dissemination of information will bw augmented by topical or final reports as appropriate.

  19. Human Immunodeficiency Virus (HIV types Western blot (WB band profiles as potential surrogate markers of HIV disease progression and predictors of vertical transmission in a cohort of infected but antiretroviral therapy naïve pregnant women in Harare, Zimbabwe

    Directory of Open Access Journals (Sweden)

    Chirenje Mike Z

    2011-01-01

    Full Text Available Abstract Background Expensive CD4 count and viral load tests have failed the intended objective of enabling access to HIV therapy in poor resource settings. It is imperative to develop simple, affordable and non-subjective disease monitoring tools to complement clinical staging efforts of inexperienced health personnel currently manning most healthcare centres because of brain drain. Besides accurately predicting HIV infection, sequential appearance of specific bands of WB test offers a window of opportunity to develop a less subjective tool for monitoring disease progression. Methods HIV type characterization was done in a cohort of infected pregnant women at 36 gestational weeks using WB test. Student-t test was used to determine maternal differences in mean full blood counts and viral load of mothers with and those without HIV gag antigen bands. Pearson Chi-square test was used to assess differences in lack of bands appearance with vertical transmission and lymphadenopathy. Results Among the 64 HIV infected pregnant women, 98.4% had pure HIV-1 infection and one woman (1.7% had dual HIV-1/HIV-2 infections. Absence of HIV pol antigen bands was associated with acute infection, p = 0.002. All women with chronic HIV-1 infection had antibody reactivity to both the HIV-1 envelope and polymerase antigens. However, antibody reactivity to gag antigens varied among the women, being 100%, 90%, 70% and 63% for p24, p17, p39 and p55, respectively. Lack of antibody reactivity to gag p39 antigen was associated with disease progression as confirmed by the presence of lymphadenopathy, anemia, higher viral load, p = 0.010, 0.025 and 0.016, respectively. Although not statistically significant, women with p39 band missing were 1.4 times more likely to transmit HIV-1 to their infants. Conclusion Absence of antibody reactivity to pol and gag p39 antigens was associated with acute infection and disease progression, respectively. Apart from its use in HIV disease

  20. Human Immunodeficiency Virus (HIV) types Western blot (WB) band profiles as potential surrogate markers of HIV disease progression and predictors of vertical transmission in a cohort of infected but antiretroviral therapy naïve pregnant women in Harare, Zimbabwe.

    Science.gov (United States)

    Duri, Kerina; Müller, Fredrik; Gumbo, Felicity Z; Kurewa, Nyaradzai E; Rusakaniko, Simba; Chirenje, Mike Z; Mapingure, Munyaradzi P; Stray-Pedersen, Babill

    2011-01-06

    Expensive CD4 count and viral load tests have failed the intended objective of enabling access to HIV therapy in poor resource settings. It is imperative to develop simple, affordable and non-subjective disease monitoring tools to complement clinical staging efforts of inexperienced health personnel currently manning most healthcare centres because of brain drain. Besides accurately predicting HIV infection, sequential appearance of specific bands of WB test offers a window of opportunity to develop a less subjective tool for monitoring disease progression. HIV type characterization was done in a cohort of infected pregnant women at 36 gestational weeks using WB test. Student-t test was used to determine maternal differences in mean full blood counts and viral load of mothers with and those without HIV gag antigen bands. Pearson Chi-square test was used to assess differences in lack of bands appearance with vertical transmission and lymphadenopathy. Among the 64 HIV infected pregnant women, 98.4% had pure HIV-1 infection and one woman (1.7%) had dual HIV-1/HIV-2 infections. Absence of HIV pol antigen bands was associated with acute infection, p = 0.002. All women with chronic HIV-1 infection had antibody reactivity to both the HIV-1 envelope and polymerase antigens. However, antibody reactivity to gag antigens varied among the women, being 100%, 90%, 70% and 63% for p24, p17, p39 and p55, respectively. Lack of antibody reactivity to gag p39 antigen was associated with disease progression as confirmed by the presence of lymphadenopathy, anemia, higher viral load, p = 0.010, 0.025 and 0.016, respectively. Although not statistically significant, women with p39 band missing were 1.4 times more likely to transmit HIV-1 to their infants. Absence of antibody reactivity to pol and gag p39 antigens was associated with acute infection and disease progression, respectively. Apart from its use in HIV disease diagnosis, WB test could also be used in conjunction with simpler

  1. Fusion materials semiannual progress report for the period ending December 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. This effort forms one element of the materials program being conducted in support of the Magnetic Fusion Energy Program of the US Department of Energy. The Fusion Materials Program is a national effort involving several national laboratories, universities, and industries. A large fraction of this work, particularly in relation to fission reactor experiments, is carried out collaboratively with partners in Japan, Russian, and the European Union. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide. The following subjects are covered: vanadium alloys; silicon carbide composite materials; ferritic/martensitic steels; copper alloys and high heat flux materials; austenitic stainless steels; insulating ceramics and optical materials; solid breeding materials; radiation effects; mechanistic studies and experimental methods dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; and irradiation facilities, test matrices and experimental methods. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  2. Research progress of cholesteric liquid crystals with broadband reflection characteristics in application of intelligent optical modulation materials

    International Nuclear Information System (INIS)

    Zhang Lan-Ying; Gao Yan-Zi; Song Ping; Yuan Xiao; He Bao-Feng; Yang Huai; Wu Xiao-Juan; Chen Xing-Wu; Hu Wang; Guo Ren-Wei; Ding Hang-Jun; Xiao Jiu-Mei

    2016-01-01

    Cholesteric liquid crystals (CLCs) have recently sparked an enormous amount of interest in the development of soft matter materials due to their unique ability to self-organize into a helical supra-molecular architecture and their excellent selective reflection of light based on the Bragg relationship. Nowadays, by the virtue of building the self-organized nanostructures with pitch gradient or non-uniform pitch distribution, extensive work has already been performed to obtain CLC films with a broad reflection band. Based on authors’ many years’ research experience, this critical review systematically summarizes the physical and optical background of the CLCs with broadband reflection characteristics, methods to obtain broadband reflection of CLCs, as well as the application in the field of intelligent optical modulation materials. Combined with the research status and the advantages in the field, the important basic and applied scientific problems in the research direction are also introduced. (topical review)

  3. Fusion materials semiannual progress report for the period ending June 30, 1996

    International Nuclear Information System (INIS)

    1996-10-01

    This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. It is divided into the following chapters: vanadium alloys; silicon carbide components; ferritic-martensitic steels; copper alloys and high heat flux materials; austenitic stainless steels; insulating ceramics and optical materials; radiation effects, mechanistic studies, and experimental methods; dosimetry, damage parameters, and activation calculations; and irradiation facilities, test matrices, and experimental methods. There were no papers for the chapters on solid breeding materials and materials engineering and design requirement. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database

  4. Fusion materials semiannual progress report for the period ending June 30, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. It is divided into the following chapters: vanadium alloys; silicon carbide components; ferritic-martensitic steels; copper alloys and high heat flux materials; austenitic stainless steels; insulating ceramics and optical materials; radiation effects, mechanistic studies, and experimental methods; dosimetry, damage parameters, and activation calculations; and irradiation facilities, test matrices, and experimental methods. There were no papers for the chapters on solid breeding materials and materials engineering and design requirement. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  5. Metals and Ceramics Division Materials Science Program. Annual progress report for period ending June 30, 1984

    Energy Technology Data Exchange (ETDEWEB)

    McHargue, C.J. (comp.)

    1984-11-01

    This report summarizes the activities of the Materials Sciences Program in the Metals and Ceramics Division for the period January 1, 1983, to June 30, 1984. These activities constitute about one-fourth of the research and development conducted by the division. The emphasis of the program can be described as the scientific design of materials. The efforts are directed toward three classes of materials: high-temperature metallic alloys based on intermetallic compounds, structural ceramics, and radiation-resistant alloys.

  6. Metals and Ceramics Division Materials Science Program. Annual progress report for period ending June 30, 1984

    International Nuclear Information System (INIS)

    McHargue, C.J.

    1984-11-01

    This report summarizes the activities of the Materials Sciences Program in the Metals and Ceramics Division for the period January 1, 1983, to June 30, 1984. These activities constitute about one-fourth of the research and development conducted by the division. The emphasis of the program can be described as the scientific design of materials. The efforts are directed toward three classes of materials: high-temperature metallic alloys based on intermetallic compounds, structural ceramics, and radiation-resistant alloys

  7. Metals and Ceramics Division materials science annual progress report for period ending June 30, 1978

    International Nuclear Information System (INIS)

    McHargue, C.J.; Peterson, S.

    1978-09-01

    Topics covered include: structure of materials, theoretical research; x-ray diffraction research; fundamental ceramics studies; preparation and synthesis of high-temperature and special service materials; physical metallurgy; grain boundary segregation and fracture; mechanisms of surface and solid-state reactions; physical properties research; superconducting materials; radiation effects; facility and technique development; nuclear microanalysis; cooperative studies with universities and other research organizations; and fundamentals of welding and joining

  8. Development and applications of photosensitive device systems to studies of biological and organic materials. Progress report

    International Nuclear Information System (INIS)

    1984-01-01

    The purpose was to develop and improve appropriate experimental techniques to the point where they could be applied to specific classes of biological problems. Progress is reported in the following areas: (1) area detectors; (2) x-ray diffraction studies of membranes; (3) electron transfer in loosely coupled systems; (4) bioluminescence and fluorescence; and (5) sonoluminescence

  9. Chemistry {ampersand} Materials Science progress report summary of selected research and development topics, FY97

    Energy Technology Data Exchange (ETDEWEB)

    Newkirk, L.

    1997-12-01

    This report contains summaries of research performed in the Chemistry and Materials Science division. Topics include Metals and Ceramics, High Explosives, Organic Synthesis, Instrument Development, and other topics.

  10. Low band gap S,N-heteroacene-based oligothiophenes as hole-transporting and light absorbing materials for efficient perovskite-based solar cells

    KAUST Repository

    Qin, Peng

    2014-07-15

    Novel low band gap oligothiophenes incorporating S,N-heteropentacene central units were developed and used as hole-transport materials (HTMs) in solid-state perovskite-based solar cells. In addition to appropriate electronic energy levels, these materials show high photo-absorptivity in the low energy region, and thus can contribute to the light harvesting of the solar spectrum. Solution-processed CH3NH3PbI3-based devices using these HTMs achieved power conversion efficiencies of 9.5-10.5% in comparison with 7.6% obtained by reference devices without HTMs. Photoinduced absorption spectroscopy gave further insight into the charge transfer behavior between photoexcited perovskites and the HTMs. This journal is © the Partner Organisations 2014.

  11. Fusion reactor materials semiannual progress report for period ending September 30, 1992

    International Nuclear Information System (INIS)

    1992-01-01

    This report contains papers on the following topics on thermonuclear reactor materials: irradiation facilities, test matrices, and experimental methods; dosimetry, damage parameters,and activation calculations; radiation effects, mechanistic studies, theory and modeling; development of structural alloys; solid breeding materials and beryllium; and ceramics. These reports have been index separately elsewhere

  12. Recent progress in research on tungsten materials for nuclear fusion applications in Europe

    Czech Academy of Sciences Publication Activity Database

    Rieth, M.; Dudarev, S.L.; Gonzalez de Vicente, S.M.; Aktaa, J.; Ahlgren, T.; Antusch, S.; Armstrong, D.E.J.; Balden, M.; Baluc, N.; Barthe, M.-F.; Basuki, W.W.; Battabyal, M.; Becquart, C.S.; Blagoeva, N.; Boldyryeva, Hanna; Brinkmann, J.; Celino, M.; Ciupinski, L.; Correia, J.B.; De Backer, A.; Domain, C.; Gaganidze, E.; García-Rosales, C.; Gibson, J.; Gilbert, M.R.; Giusepponi, S.; Gludovatz, B.; Greuner, H.; Heinola, K.; Höschen, T.; Hoffmann, A.; Holstein, A.; Koch, F.; Krauss, W.; Li, H.; Lindig, S.; Linke, J.; Linsmeier, Ch.; López-Ruiz, P.; Maier, H.; Matějíček, Jiří; Mishra, T.P.; Muhammed, M.; Muñoz, A.; Muzyk, M.; Nordlund, K.; Nguyen-Manh, D.; Opschoor, J.; Ordás, N.; Palacios, Y.; Pintsuk, G.; Pippan, R.; Reiser, J.; Riesch, J.; Roberts, S. G.; Romaner, L.; Rosiński, M.; Sanchez, M.; Schulmeyer, W.; Traxler, H.; Ureña, G.; van der Laan, J.G.; Veleva, L.; Wahlberg, S.; Walter, M.; Weber, T.; Weitkamp, T.; Wurster, S.; Yar, M.A.; You, J.H.; Zivelonghi, A.

    2013-01-01

    Roč. 432, 1-3 (2013), s. 482-500 ISSN 0022-3115 Institutional support: RVO:61389021 Keywords : tungsten * joining * composites * graded materials * fusion materials Subject RIV: JF - Nuclear Energetics Impact factor: 2.016, year: 2013 http://www.sciencedirect.com/science/article/pii/S0022311512004278

  13. Recent Progress in Nanostructured Oxide TE Materials for Power Generation at High Temperatures

    DEFF Research Database (Denmark)

    Van Nong, Ngo; Pryds, Nini; Linderoth, Søren

    Thermoelectric (TE) materials, which can convert waste heat into electricity, could play an important role in a global sustainable energy solution and environmental problems. Metal oxides have been considered as potential TE materials for power generation that can operate at high temperatures...

  14. Metals and Ceramics Division Materials Science Program. Annual progress report for period ending December 31, 1982

    International Nuclear Information System (INIS)

    McHargue, C.J.

    1983-05-01

    This report summarizes the activities of the Materials Sciences Program in the Metals and Ceramics Division. These activities constitute about one-fourth of the research and development conducted by the division. The major elements of the Materials Sciences Program can be grouped under the areas of (1) structural characterization, (2) high-temperature alloy studies, (3) structural ceramics, and (4) radiation effects

  15. Fusion reactor materials semiannual progress report for the period ending March 31, 1990

    International Nuclear Information System (INIS)

    1990-08-01

    This report mainly discusses topics on the physical effects of radiation on thermonuclear reactor materials. The areas discussed are: irradiation facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; fundamental mechanical behavior; radiation effects; mechanistic studies, theory and modeling; development of structural alloys; solid breeding materials; and ceramics. (FI)

  16. University of Illinois at Urbana-Champaign, Materials Research Laboratory progress report for FY 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-07-01

    This interdisciplinary laboratory in the College of Engineering support research in areas of condensed matter physics, solid state chemistry, and materials science. These research programs are developed with the assistance of faculty, students, and research associates in the departments of Physics, Materials Science and Engineering, chemistry, Chemical Engineering, Electrical Engineering, Mechanical Engineering, and Nuclear Engineering.

  17. Metals and Ceramics Division Materials Science Program. Annual progress report for period ending December 31, 1982

    Energy Technology Data Exchange (ETDEWEB)

    McHargue, C.J. (comp.)

    1983-05-01

    This report summarizes the activities of the Materials Sciences Program in the Metals and Ceramics Division. These activities constitute about one-fourth of the research and development conducted by the division. The major elements of the Materials Sciences Program can be grouped under the areas of (1) structural characterization, (2) high-temperature alloy studies, (3) structural ceramics, and (4) radiation effects.

  18. Science of materials. Progress report, January 1, 1981-December 31, 1981

    International Nuclear Information System (INIS)

    1981-01-01

    The research program is designed to provide information concerning basic properties of materials that are important for the development of energy systems. The emphasis is on the synthesis and characterization of new materials with novel properties for future applications. The research program includes studies of the microchemistry and microstructure; the deformation, corrosion and fracture of metals, ceramics and alloy materials are of particular concern, as is the hydrogen embrittlement of metals; also under investigation are the mechanism of heat transfer across interfaces, catalytic properties of surfaces, and erosion of surfaces by fluid suspended particles. The new materials and materials configurations now being fabricated for research on energy applications include a variety of metastable ceramic, metallic, semi-conducting and molecular assemblies

  19. Heavy Vehicle Propulsion System Materials Program semiannual progress report for October 1996 through March 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks. The design of advanced components for high-efficiency diesel engines has, in some cases, pushed the performance envelope for materials of construction past the point of reliable operation. Higher mechanical and tribological stresses and higher temperatures of advanced designs limit the engine designers; advanced materials allow the design of components that may operate reliably at higher stresses and temperatures, thus enabling more efficient engine designs. Advanced materials also offer the opportunity to improve the emissions, NVH, and performance of diesel engines for pickup trucks, vans, and sport utility vehicles. The principal areas of research are: (1) cost effective high performance materials and processing; (2) advanced manufacturing technology; (3) testing and characterization; and (4) materials and testing standards.

  20. 1996 Progress report on energies and raw materials; 1996 rapport d`activite energies et matieres premieres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The 1996 annual progress report, from the French Department of Energy, reviews the key points of the French policy for energy and raw materials: competitiveness, environmental protection, long term supply safety, and public service. 1996 was marked by positive results for the French energy industry, difficulties for the oil refining industry, and a new impetus for renewable energies. Five surveys are presented: nuclear safety in Eastern Europe, the european directive on electric power domestic market, evolution of the oil market, conditions of refining in France, and restructuring of the Mine bureau (BRGM). 40 prominent facts are briefly reviewed, concerning sustainable energy development, nuclear energy, electric power and gas, coal, oil products, raw materials. Diagrams on energy and raw materials are also included

  1. Materials Compatibility and Lubricants Research on CFC-refrigerant substitutes. Quarterly progress report, 1 July 1992--30 September 1992

    Energy Technology Data Exchange (ETDEWEB)

    Hourahan, G.C.; Szymurski, S.R.

    1992-10-01

    The Materials Compatibility and Lubricants Research (MCLR) program supports critical research to accelerate the introduction of CFC-refrigerant substitutes. The MCLR program addresses refrigerant and lubricant properties and materials compatibility. The primary elements of the work include data collection and dissemination, materials compatibility testing, and methods development. The work is guided by an Advisory Committee consisting of technical experts from the refrigeration and air-conditioning industry and government agencies. Under the current MCLR pregrain the Air-Conditioning and Refrigeration Technology Institute, Inc., (ARTI) is contracting and managing several research projects and a data collection and dissemination effort. Preliminary results is from these projects are reported in technical progress reports prepared by each researcher.

  2. Research Progress on 3D Printed Graphene Materials Synthesis Technology and Its Application in Energy Storage Field

    Directory of Open Access Journals (Sweden)

    WANG Nan

    2017-12-01

    Full Text Available Graphene is an ideal material for energy storage application as its excellent mechanical and physical properties. 3D printed graphene materials will be widely applied in energy storage field for its precisely controllable structure and it is easy to realize large-scale preparation. In this paper, the progress of 3D printed graphene materials synthesis technology and its application in energy storage field were reviewed. The viscosity and printability of graphene ink are key factors for realizing graphene 3D printing. Scalable preparation of graphene ink with facile process, controllable concentration and additive free will be the research focus of graphene 3D printing technologies in the future. The integrated printing of graphene energy storage devices such as graphene supercapacitor, lithium-sulfur battery and lithium ion battery is the development direction in this area.

  3. Isotopic power materials development. Quarterly progress report for period ending March 31, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Schaffhauser, A.C.

    1976-06-01

    The second in a series of quarterly reports for Technology and Space Applications materials programs conducted by the Metals and Ceramics Division of Oak Ridge National Laboratory for the Nuclear Research and Applications Division of ERDA is presented. These quarterly reports replace the monthly and annual reports previously issued on this work. The areas of research covered include high-temperature alloys for space isotopic heat sources, physical and mechanical metallurgy of heat source containment materials, isotope Brayton system materials support, and space nuclear flight systems hardware. (TFD)

  4. Progress in Indentation Study of Materials via Both Experimental and Numerical Methods

    Directory of Open Access Journals (Sweden)

    Mao Liu

    2017-10-01

    Full Text Available Indentation as a method to characterize materials has a history of more than 117 years. However, to date, it is still the most popular way to measure the mechanical properties of various materials at microscale and nanoscale. This review summarizes the background and the basic principle of processing by indentation. It is demonstrated that indentation is an effective and efficient method to identify mechanical properties, such as hardness, Young’s modulus, etc., of materials at smaller scale, when the traditional tensile tests could not be applied. The review also describes indentation process via both experimental tests and numerical modelling in recent studies.

  5. A Study on Changes in Thickness of STS304 Material in the Progressive Drawing Process

    Directory of Open Access Journals (Sweden)

    Lee C.K.

    2017-06-01

    Full Text Available In the drawing process, the roundness of corners in the punch and the die are very important factors in determining the thicknesses of the product. The results clearly revealed that the thickness of a flange was increased and the thickness of body parts reduced when the roundness of the die entrance was small. The material thickness of the top part was decreased when the corner roundness of the punch was large. The smooth inflow of materials was found to have a significant effect on the thickness during the post-process. The compressive strength of STS 304 material exhibited a higher value compared with other processing methods. Moreover, we clearly observed the corner roundness of the punch and the die to be a very important factor for STS 304 materials.

  6. Advances in materials science, metals and ceramics division. Triannual progress report, June-September 1980

    International Nuclear Information System (INIS)

    Truhan, J.J.; Hopper, R.W.; Gordon, K.M.

    1980-01-01

    Information is presented concerning the magnetic fusion energy program; the laser fusion energy program; geothermal research; nuclear waste management; Office of Basic Energy Sciences (OBES) research; diffusion in silicate minerals; chemistry research resources; and chemistry and materials science research

  7. Progress in high-efficient solution process organic photovoltaic devices fundamentals, materials, devices and fabrication

    CERN Document Server

    Li, Gang

    2015-01-01

    This book presents an important technique to process organic photovoltaic devices. The basics, materials aspects and manufacturing of photovoltaic devices with solution processing are explained. Solution processable organic solar cells - polymer or solution processable small molecules - have the potential to significantly reduce the costs for solar electricity and energy payback time due to the low material costs for the cells, low cost and fast fabrication processes (ambient, roll-to-roll), high material utilization etc. In addition, organic photovoltaics (OPV) also provides attractive properties like flexibility, colorful displays and transparency which could open new market opportunities. The material and device innovations lead to improved efficiency by 8% for organic photovoltaic solar cells, compared to 4% in 2005. Both academic and industry research have significant interest in the development of this technology. This book gives an overview of the booming technology, focusing on the solution process fo...

  8. Progress report: Chemistry and Materials Division, 1983 January 1 - June 30

    International Nuclear Information System (INIS)

    1983-08-01

    The research progams in solid state science, analytical and physical chemistry and materials science are outlined for the first half of 1983. Studies are being carried out in the areas of surface science, isotope separation and irradiation effects on zirconium

  9. Progress in High-Capacity Core-Shell Cathode Materials for Rechargeable Lithium Batteries.

    Science.gov (United States)

    Myung, Seung-Taek; Noh, Hyung-Joo; Yoon, Sung-June; Lee, Eung-Ju; Sun, Yang-Kook

    2014-02-20

    High-energy-density rechargeable batteries are needed to fulfill various demands such as self-monitoring analysis and reporting technology (SMART) devices, energy storage systems, and (hybrid) electric vehicles. As a result, high-energy electrode materials enabling a long cycle life and reliable safety need to be developed. To ensure these requirements, new material chemistries can be derived from combinations of at least two compounds in a secondary particle with varying chemical composition and primary particle morphologies having a core-shell structure and spherical cathode-active materials, specifically a nanoparticle core and shell, nanoparticle core and nanorod shell, and nanorod core and shell. To this end, several layer core-shell cathode materials were developed to ensure high capacity, reliability, and safety.

  10. Progress on immobilisation of plutonium residues and shredded plutonium contaminated materials in cement

    International Nuclear Information System (INIS)

    Landles, A.J.; Awmack, A.F.; Baxter, W.

    1987-03-01

    Laboratory scale experiments have been carried out to study the feasibility of encapsulating plutonium contaminated materials in cement. A proposed grout of a 3:1 PFA/OPC mixture has been tested and some product evaluation carried out. (author)

  11. Advances in materials science, metals and ceramics division. Triannual progress report, June-September 1980

    Energy Technology Data Exchange (ETDEWEB)

    Truhan, J.J.; Hopper, R.W.; Gordon, K.M. (eds.)

    1980-10-28

    Information is presented concerning the magnetic fusion energy program; the laser fusion energy program; geothermal research; nuclear waste management; Office of Basic Energy Sciences (OBES) research; diffusion in silicate minerals; chemistry research resources; and chemistry and materials science research.

  12. 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)

  13. Progress in 3D Printing of Carbon Materials for Energy-Related Applications.

    Science.gov (United States)

    Fu, Kun; Yao, Yonggang; Dai, Jiaqi; Hu, Liangbing

    2017-03-01

    The additive-manufacturing (AM) technique, known as three-dimensional (3D) printing, has attracted much attention in industry and academia in recent years. 3D printing has been developed for a variety of applications. Printable inks are the most important component for 3D printing, and are related to the materials, the printing method, and the structures of the final 3D-printed products. Carbon materials, due to their good chemical stability and versatile nanostructure, have been widely used in 3D printing for different applications. Good inks are mainly based on volatile solutions having carbon materials as fillers such as graphene oxide (GO), carbon nanotubes (CNT), carbon blacks, and solvent, as well as polymers and other additives. Studies of carbon materials in 3D printing, especially GO-based materials, have been extensively reported for energy-related applications. In these circumstances, understanding the very recent developments of 3D-printed carbon materials and their extended applications to address energy-related challenges and bring new concepts for material designs are becoming urgent and important. Here, recent developments in 3D printing of emerging devices for energy-related applications are reviewed, including energy-storage applications, electronic circuits, and thermal-energy applications at high temperature. To close, a conclusion and outlook are provided, pointing out future designs and developments of 3D-printing technology based on carbon materials for energy-related applications and beyond. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Heavy vehicle propulsion system materials program semiannual progress report for April 1999 through September 1999

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.

    2000-01-01

    The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks.

  15. Heavy Vehicle Propulsion System Materials Program Semiannual Progress Report for October 1998 Through March 1999

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.D.

    1999-06-01

    The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks. The Office of Transportation Technologies, Office of Heavy Vehicle Technologies (OIT OHVT) has an active program to develop the technology for advanced LE-55 diesel engines with 55% efficiency and low emissions levels of 2.0 g/bhp-h NOX and 0.05 g/bhp-h particulate. The goal is also for the LE-55 engine to run on natural gas with efficiency approaching that of diesel fuel. The LE-55 program is being completed in FY 1997 and, after approximately 10 years of effort, has largely met the program goals of 55% efficiency and low emissions. However, the commercialization of the LE-55 technology requires more durable materials than those that have been used to demonstrate the goals. Heavy Vehicle Propulsion System Materials will, in concert with the heavy duty diesel engine companies, develop the durable materials required to commercialize the LE-55 technologies. OIT OHVT also recognizes a significant opportunity for reduction in petroleum consumption by dieselization of pickup trucks, vans, and sport utility vehicles. Application of the diesel engine to class 1,2, and 3 trucks is expected to yield a 35% increase in fuel economy per vehicle. The foremost barrier to diesel use in this market is emission control. Once an engine is made certifiable, subsequent challenges will be in cost; noise, vibration, and harshness (NVH); and performance. The design of advanced components for high-efficiency diesel engines has, in some cases, pushed the performance envelope for materials of construction past the point of reliable operation. Higher mechanical and

  16. Progress in the chemistry of chromium(V) doping agents used in polarized target materials

    International Nuclear Information System (INIS)

    Krumpolc, M.; Hill, D.; Struhrmann, H.B.

    1990-01-01

    We wish to report progress in two areas of the chromium (V)-based doping agents: Two commonly used chromium (V) complexes, I and II, have been synthesized in perdeuterated form (i.e., all hydrogens replaced by deuterium). They are sodium bis(2-ethyl-2-deuteroxy-butyrato)oxochromate(V)monodeuterate, IV, (acronym EDBA-Cr(V)), and sodium bis(2-deuteroxy-2-methylpropionato)oxochromate(V), III, (acronym DMPA-Cr(V)). A synthetic route leading to the preparation of stable, chromium(III)-free solutions of chromium(V) in diols (1,2-ethanediol/ethylene glycol/and 1,2-propanediol/propylene glycol/) has been outlined

  17. Potential use of Plastic Waste as Construction Materials: Recent Progress and Future Prospect

    Science.gov (United States)

    Kamaruddin, M. A.; Abdullah, M. M. A.; Zawawi, M. H.; Zainol, M. R. R. A.

    2017-11-01

    Plastic associates products based have been considered as the world most consumer packaging solution. However, substantial quantities of plastic consumption have led to exponential increase of plastic derived waste. Recycling of plastic waste as valued added product such as concrete appears as one of promising solution for alternative use of plastic waste. This paper summarized recent progress on the development of concrete mixture which incorporates plastic wastes as partial aggregate replacement during concrete manufacturing. A collection of data from previous studies that have been researched which employed plastic waste in concrete mixtures were evaluated and conclusions are drawn based on the laboratory results of all the mentioned research papers studied.

  18. Heavy vehicle propulsion system materials program semiannual progress report for April 1998 thru September 1998

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.

    1999-01-01

    The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1--3 trucks to realize a 35{percent} fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7--8 trucks. The Office of Transportation Technologies, Office of Heavy Vehicle Technologies (OTT OHVT) has an active program to develop the technology for advanced LE-55 diesel engines with 55{percent} efficiency and low emissions levels of 2.0 g/bhp-h NO{sub x} and 0.05 g/bhp-h particulates. The goal is also for the LE-55 engine to run on natural gas with efficiency approaching that of diesel fuel. The LE-55 program is being completed in FY 1997 and, after approximately 10 years of effort, has largely met the program goals of 55{percent} efficiency and low emissions. However, the commercialization of the LE-55 technology requires more durable materials than those that have been used to demonstrate the goals. Heavy Vehicle Propulsion System Materials will, in concert with the heavy-duty diesel engine companies, develop the durable materials required to commercialize the LE-55 technologies.

  19. Progress in the electrochemical modification of graphene-based materials and their applications

    International Nuclear Information System (INIS)

    Chakrabarti, M.H.; Low, C.T.J.; Brandon, N.P.; Yufit, V.; Hashim, M.A.; Irfan, M.F.; Akhtar, J.; Ruiz-Trejo, E.; Hussain, M.A.

    2013-01-01

    Highlights: • Six means of functionalizing graphene electrochemically is reviewed. • Electrochemical functionalization is relatively new to other standard methods. • The technique is expected to improve graphene's application range considerably. -- Abstract: Graphene is a 2D allotrope of carbon with exciting properties such as extremely high electronic conductivity and superior mechanical strength. It has considerable potential for applications in fields such as bio-sensors, electrochemical energy storage and electronics. In most cases, graphene has been functionalized and modified with other materials to prepare composites. This work reviews the electrochemical modification of graphene. Commencing with a brief history, a summary of several different means of modifying graphene to effect diverse applications is provided. This is followed by a discussion on different composite materials that have been prepared with reduced graphene oxide prior to moving onto a detailed consideration of six different methods of electrochemically modifying graphene to prepare composite materials. These methods involve cathodic reduction of graphene oxide, electrophoretic deposition, electro-deposition techniques, electrospinning, electrochemical doping and electrochemical polymerization. Finally a consideration on the applications of electrochemically modified graphene composite materials in various fields is presented prior to discussing some prospects in enhancing the electrochemical process to realize excellent and economic composite materials in bulk

  20. Decay of superdeformed bands

    International Nuclear Information System (INIS)

    Carpenter, M.P.; Khoo, T.L.; Lauritsen, T.

    1995-01-01

    One of the major challenges in the study of superdeformation is to directly connect the large number of superdeformed bands now known to the yrast states. In this way, excitation energies, spins and parities can be assigned to the levels in the second well which is essential to establish the collective and single-particle components of these bands. This paper will review some of the progress which has been made to understand the decay of superdeformed bands using the new arrays including the measurement of the total decay spectrum and the establishment of direct one-step decays from the superdeformed band to the yrast line in 194 Hg. 42 refs., 5 figs

  1. Progress on materials and scaffold fabrications applied to esophageal tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Qiuxiang; Shi, Peina; Gao, Mongna; Yu, Xuechan; Liu, Yuxin; Luo, Ling; Zhu, Yabin, E-mail: zhuyabin@nbu.edu.cn

    2013-05-01

    The mortality rate from esophageal disease like atresia, carcinoma, tracheoesophageal fistula, etc. is increasing rapidly all over the world. Traditional therapies such as surgery, radiotherapy or chemotherapy have been met with very limited success resulting in reduced survival rate and quality of patients' life. Tissue-engineered esophagus, a novel substitute possessing structure and function similar to native tissue, is believed to be an effective therapy and a promising replacement in the future. However, research on esophageal tissue engineering is still at an early stage. Considerable research has been focused on developing ideal scaffolds with optimal materials and methods of fabrication. This article gives a review of materials and scaffold fabrications currently applied in esophageal tissue engineering research. - Highlights: ► Natural and synthesized materials are being developed as scaffold matrices. ► Several technologies have been applied to reconstruct esophagus tissue scaffold. ► Tissue-engineered esophagus is a promising artificial replacement.

  2. Recent progress in the growth and applications of graphene as a smart material: A review

    Science.gov (United States)

    Aissa, Brahim; Memon, Nasir; Ali, Adnan; Khraisheh, Marwan

    2015-09-01

    Innovative breakthroughs in fundamental research and industrial applications of graphene material have made its mass and low-cost production a necessary step toward its real world applications. This one-atom thick crystal of carbon, gathers a set of unique physico-chemical properties, ranging from its extreme mechanical behavior to its exceptional electrical and thermal conductivities, which are making graphene as a serious alternative to replace many conventional materials for various applications. In this review paper, we highlight the most important experimental results on the synthesis of graphene material, its emerging properties with reference to its smart applications. We discuss the possibility to successfully integrating graphene directly into device, enabling thereby the realization of a wide range of applications, including actuation, photovoltaic, thermoelectricity, shape memory, self-healing, electrorheology and space missions. The future outlook of graphene is also considered and discussed.

  3. Recent progress in the growth and applications of graphene as a smart material: A review

    Directory of Open Access Journals (Sweden)

    Brahim eAissa

    2015-09-01

    Full Text Available Innovative breakthroughs in fundamental research and industrial applications of graphene material have made its mass and low-cost production a necessary step toward its real world applications. This one-atom thick crystal of carbon, gathers a set of unique physico-chemical properties, ranging from its extreme mechanical behavior to its exceptional electrical and thermal conductivities, which are making graphene as a serious alternative to replace many conventional materials for various applications. In this review paper, we highlight the most important experimental results on the synthesis of graphene material, its emerging properties with reference to its smart applications. We discuss the possibility to successfully integrating graphene directly into device, enabling thereby the realization of a wide range of applications, including actuation, photovoltaic, thermoelectricity, shape memory, self-healing, electrorheology and space missions. The future outlook of graphene is also considered and discussed.

  4. Helium generation in fusion reactor materials. Technical progress report, April--September 1977

    International Nuclear Information System (INIS)

    1978-01-01

    The near-term objectives of this program are to measure the spectrum-integrated helium generation rates and cross sections of a number of pure elements and alloys in several high-intensity neutron sources, and to develop and demonstrate neutron dosimetry procedures using some of these materials. To this end, four neutron irradiation experiments have now been run: one using accelerator-produced d-Be neutrons, two using the accelerator-produced d-T reaction, and one in the neutron field of a mixed-spectrum fission reactor. All of these irradiations have incorporated a large number of helium-generation materials

  5. A comparative evaluation of the tensile strength of silver soldered joints of stainless steel and cobalt chromium orthodontic wires with band material--an in vitro study.

    Science.gov (United States)

    Dua, R; Nandlal, B

    2004-03-01

    The present study was conducted to compare and evaluate the tensile strength of silver soldered joints of stainless steel and cobalt-chromium orthodontic wires with band material. An attempt was made to observe the effect of joint site preparation by incorporation of tack welding and increasing metal to metal surface contact area by flattening an end of the wire prior to soldering along with the regularly used round wires without tack welding. A total of 180 wire specimens were soldered to 180 band specimens. Fifteen samples according to joint site preparation were included for each of the wire groups i.e. Gloria (S.S.), Remanium (S.S.) and Remaloy (Co-Cr) wires of 0.036" in diameter. The findings of the study were suggestive that all three wires may be used for preparing silver soldered joints irrespective of the quality of the wire. However, when subjecting the wire to joint site preparation, Gloria (S.S.) wire showed less tensile strength as compared to Remanium and Remaloy.

  6. Improved performance of dye sensitized solar cells using Cu-doped TiO2 as photoanode materials: Band edge movement study by spectroelectrochemistry

    Science.gov (United States)

    Zhou, Li; Wei, Liguo; Yang, Yulin; Xia, Xue; Wang, Ping; Yu, Jia; Luan, Tianzhu

    2016-08-01

    Cu-doped TiO2 nanoparticles are prepared and used as semiconductor materials of photoanode to improve the performance of dye sensitized solar cells (DSSCs). UV-Vis spectroscopy and variable temperature spectroelectrochemistry study are used to characterize the influence of copper dopant with different concentrations on the band gap energies of TiO2 nanoparticles. The prepared Cu-doped TiO2 semiconductor has avoided the formation of CuO during hydrothermal process and lowered the conduction band position of TiO2, which contribute to increase the short circuit current density of DSSCs. At the optimum Cu concentration of 1.0 at.%, the short circuit current density increased from 12.54 to 14.98 mA cm-2, full sun solar power conversion efficiencies increased from 5.58% up to 6.71% as compared to the blank DSSC. This showed that the presence of copper in DSSCs leads to improvements of up to 20% in the conversion efficiency of DSSCs.

  7. Progress report, Chemistry and Materials Division, April 1 to June 30, 1977

    International Nuclear Information System (INIS)

    1977-07-01

    Research results are reported in such areas as ion penetration, electron microscopy, metal physics and radiation damage, nuclear methods of analysis, fuel analysis, and general analytical chemistry, electrochemistry, radiation chemistry, hydrogen-deuterium exchange, and surface chemistry of nuclear materials like zirconium base alloys. (E.C.B.)

  8. Progress report chemistry and materials division 1984 January 1 - June 30

    International Nuclear Information System (INIS)

    1984-08-01

    During the first half of 1984 work in the Chemistry and Materials Division of Chalk River Nuclear Laboratories concentrated on studies of ion penetration phenomena, surface phenomena, radiation damage, radiochemical analysis, recycle fuel analysis, gamma spectrometry, mass spectrometry of fuels and moderators, analysis of hydrogen in zirconium alloys, burnup analysis, radiolysis, hydrogen isotope separation, hydrogen adsorption, zirconium corrosion, and metal physics studies of zirconium

  9. Heavy fermion and actinide materials. Annual technical progress report, February 1, 1992--January 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-02-01

    During this period, 1/N expansions have been systematically applied to the calculation of the properties of highly correlated electron systems. These studies include examinations of (a) the class of materials known as heavy fermion semi-conductors, (b) the high energy spectra of heavy fermion systems, and (c) the doped oxide superconductors.

  10. Metals and Ceramics Division Materials Sciences Program: Annual progress report for period ending June 30, 1987

    Energy Technology Data Exchange (ETDEWEB)

    Stiegler, J.O. (comp.)

    1988-04-01

    The program is directed at uncovering principles for the scientific design of materials. The efforts emphasize three classes of materials: high-temperature metallic alloys based on intermetallic compounds, structural ceramics, and radiation-resistant alloys. The first two materials are central to the theme of the High Temperature Materials Laboratory, and the third supports the Laboratory's mission in fission and fusion reactor technology. We combine the use of unique structural characterization facilities, the activities of the Theory Group, and accurate property determination to establish structure-property relationships. An important aspect of the program is the interaction with universities, industry, and other laboratories. Two collaborative research centers established to aid these interactions are SHaRe and ORSOAR, which make our strong structural characterization capabilities available to researchers outside ORNL. Their research activities and capabilities are summarized in Chap. 1, ''Structural Characterization,'' and Chap. 6, ''Collaborative Research Centers.'' Other interactions with the scientific community are summarized in the Appendixes.

  11. Progress report, Chemistry and Materials Division, October 1 to December 31, 1975

    International Nuclear Information System (INIS)

    1976-01-01

    Interim research results are reported in solid state science (ion penetration, electron microscopy, radiation damage and metal physics, nuclear methods of analysis), general chemistry (analytical chemistry, hydrogen-water exchange, radioactivity measurements, electrochemistry), physical chemistry (radiation and isotope chemistry), materials science (surface chemistry and metal physics), and university research (deuterium exchange and zirconium alloy properties). (E.C.B.)

  12. Recent progress in transparent conducting materials by use of metallic grids on metaloxides

    NARCIS (Netherlands)

    Deelen, J. van; Rendering, H.; Hovestad, A.

    2012-01-01

    Alternatives to ITO are under heavy investigation. Organic and inorganic transparent conducting materials are compared based on their transparency versus sheet resistance characteristics. Although graphene has advanced recently, TCOs are still superior in performance and can only be surpassed by the

  13. Recent progress in mesoporous titania materials: adjusting morphology for innovative applications

    Directory of Open Access Journals (Sweden)

    Juan L Vivero-Escoto, Ya-Dong Chiang, Kevin C-W Wu and Yusuke Yamauchi

    2012-01-01

    Full Text Available This review article summarizes recent developments in mesoporous titania materials, particularly in the fields of morphology control and applications. We first briefly introduce the history of mesoporous titania materials and then review several synthesis approaches. Currently, mesoporous titania nanoparticles (MTNs have attracted much attention in various fields, such as medicine, catalysis, separation and optics. Compared with bulk mesoporous titania materials, which are above a micrometer in size, nanometer-sized MTNs have additional properties, such as fast mass transport, strong adhesion to substrates and good dispersion in solution. However, it has generally been known that the successful synthesis of MTNs is very difficult owing to the rapid hydrolysis of titanium-containing precursors and the crystallization of titania upon thermal treatment. Finally, we review four emerging fields including photocatalysis, photovoltaic devices, sensing and biomedical applications of mesoporous titania materials. Because of its high surface area, controlled porous structure, suitable morphology and semiconducting behavior, mesoporous titania is expected to be used in innovative applications.

  14. Magnetic fusion energy materials technology program, annual progress report for period ending June 30, 1976

    International Nuclear Information System (INIS)

    Scott, J.L.

    1976-09-01

    Activities in research programs are reported on materials for use in thermonuclear reactor development. Information and data are included on radiation effects on stainless steel 316, nickel-base alloys, molybdenum-base alloys, vanadium alloys, and SAP. Results of compatibility studies involving iron-base alloys and lithium are also included along with research results on magnet development

  15. Magnetic fusion energy materials technology program, annual progress report for period ending June 30, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Scott, J.L. (comp.)

    1976-09-01

    Activities in research programs are reported on materials for use in thermonuclear reactor development. Information and data are included on radiation effects on stainless steel 316, nickel-base alloys, molybdenum-base alloys, vanadium alloys, and SAP. Results of compatibility studies involving iron-base alloys and lithium are also included along with research results on magnet development. (JRD)

  16. Helium generation in fusion-reactor materials. Progress report, October-December 1982

    International Nuclear Information System (INIS)

    Kneff, D.W.; Farrar, H. IV.

    1982-01-01

    The objectives of this work are to measure helium generation rates of materials for Magnetic Fusion Reactor applications in the Be(d,n) neutron environment, to characterize this neutron environment, and to develop helium accumulation neutron dosimeters for routine neutron fluence and energy spectrum measurements in Be(d,n) and Li(d,n) neutron fields

  17. Electromagnetic material changes for remote detection and monitoring: a feasibility study: Progress report

    Energy Technology Data Exchange (ETDEWEB)

    McCloy, John S.; Jordan, David V.; Kelly, James F.; McMakin, Douglas L.; Johnson, Bradley R.; Campbell, Luke W.

    2009-09-01

    A new concept for radiation detection is proposed, allowing a decoupling of the sensing medium and the readout. An electromagnetic material, such as a magnetic ceramic ferrite, is placed near a source to be tracked such as a shipping container. The electromagnetic material changes its properties, in this case its magnetic permeability, as a function of radiation. This change is evident as a change in reflection frequency and magnitude when probed using a microwave/millimeter-wave source. This brief report discusses modeling of radiation interaction of various candidate materials using a radiation detector modeling code Geant4, system design considerations for the remote readout, and some theory of the material interaction physics. The theory of radiation change in doped magnetic insulator ferrites such as yttrium iron garnet (YIG) seems well founded based on literature documentation of the photomagnetic effect. The literature also suggests sensitivity of permittivity to neutrons in some ferroelectrics. Research to date indicates that experimental demonstration of these effects in the context of radiation detection is warranted.

  18. Progress report on R + D activities in 1980 of the Institut fuer Material- und Festkoerperforschung

    International Nuclear Information System (INIS)

    1981-02-01

    The activities of IMF in the following fields are discussed: 1) Project Schneller Brueter (core, cladding, and structural materials; safety analyses; instrumentation; core monitoring.) 2) Project Nukleare Sicherheit (fuel element behaviour during accidents; core meltdown) 3) Project Wiederaufarbeitung und Abfallbehandlung (reprocessing and waste treatment) 4) Fusion technology 5) Innovation research. (RW) [de

  19. Department F3. Condensed matter research and materials sciences. Progress report 1989

    International Nuclear Information System (INIS)

    Gaeggeler, H.W.; Lorenzen, R.

    1990-04-01

    The report deals with work done during 1989 in the field of muon spectroscopy, neutron scattering, cryogenic detectors, accelerator mass spectrometry, geochemistry, trace elements, aerosol chemistry, heavy elements, cement products, defect physics, irradiation damages in fusion reactor materials, and superconductivity. 135 figs., 15 tabs. 417 refs

  20. Mechanical properties test data for structural materials. Quarterly progress report for period ending October 31, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Hill, M R [comp.

    1976-12-01

    Test data on heat resisting reactor materials are presented. These data were obtained in research at EG and G Idaho, Argonne National Laboratory, Oak Ridge National Laboratory, Naval Research Laboratory, Hanford Engineering Development Laboratory, Westinghouse Advanced Reactors Division, General Electric Company, University of Cincinnati, and University of California at Los Angeles. (JRD)

  1. Heavy vehicle propulsion system materials program: Semiannual progress report, April 1996--September 1996

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.

    1997-04-01

    The purpose of the Heavy Vehicle Propulsion System Materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1-3 trucks to realize a 35% fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7-8 trucks. The Office of Transportation Technologies, Office of Heavy Vehicle Technologies (OTT OHVT) has an active program to develop the technology for advanced LE-55 diesel engines with 55% efficiency and low emissions levels of 2.0 g/bhp-h NO{sub x} and 0.05 g/bhp-h particulates. The goal is also for the LE-55 engine to run on natural gas with efficiency approaching that of diesel fuel. The LE-55 program is being completed in FY 1997 and, after approximately 10 years of effort, has largely met the program goals of 55% efficiency and low emissions. However, the commercialization of the LE-55 technology requires more durable materials than those that have been used to demonstrate the goals. Heavy Vehicle Propulsion System Materials will, in concert with the heavy duty diesel engine companies, develop the durable materials required to commercialize the LE-55 technologies. OTT OHVT also recognizes a significant opportunity for reduction in petroleum consumption by dieselization of pickup trucks, vans, and sport utility vehicles. Application of the diesel engine to class 1, 2, and 3 trucks is expected to yield a 35% increase in fuel economy per vehicle. The foremost barrier to diesel use in this market is emission control. Once an engine is made certifiable, subsequent challenges will be in cost; noise, vibration, and harshness (NVH); and performance. Separate abstracts have been submitted to the database for contributions to this report.

  2. Propulsion system materials program. Semiannual progress report, October 1995--March 1996

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.

    1996-07-01

    This portion of the program is identified as program element 1.0 within the work breakdown structure (WBS). It contains five subelements: (1) Monolithics, (2) Ceramic Composites, (3) Thermal and Wear Coatings, (4) Joining, and (5) Ceramic Machining. Ceramic research conducted within the Monolithics subelement currently includes work activities on low Cost Si{sub 3}N{sub 4} powder, green state ceramic fabrication, characterization, and densification, and on structural, mechanical, and physical properties of these ceramics. Research conducted within the Ceramic Composites subelement currently includes silicon nitride and oxide-based composites, and low expansion materials. Research conducted in the Thermal and Wear Coatings subelement is currently limited to oxide-based coatings and involves coating synthesis, characterization, and determination of the mechanical and physical properties of the coatings. Research conducted in the Joining subelement currently includes studies of processes to produce strong, stable joints between zirconia ceramics and iron-base alloys. As part of an expanded effort to reduce the cost of ceramic components, a new initiative in cost effective machining has been started. A major objective of the research in the Materials and Processing program element is to systematically advance the understanding of the relationships between ceramic raw materials such as powders and reactant gases, the processing variables involved in producing the ceramic materials, and the resultant microstructures and physical and mechanical properties of the ceramic materials. Success in meeting this objective will provide U.S. companies with new or improved ways for producing economical, highly reliable ceramic components for advanced heat engines.

  3. The Effect of Scale Dependent Discretization on the Progressive Failure of Composite Materials Using Multiscale Analyses

    Science.gov (United States)

    Ricks, Trenton M.; Lacy, Thomas E., Jr.; Pineda, Evan J.; Bednarcyk, Brett A.; Arnold, Steven M.

    2013-01-01

    A multiscale modeling methodology, which incorporates a statistical distribution of fiber strengths into coupled micromechanics/ finite element analyses, is applied to unidirectional polymer matrix composites (PMCs) to analyze the effect of mesh discretization both at the micro- and macroscales on the predicted ultimate tensile (UTS) strength and failure behavior. The NASA code FEAMAC and the ABAQUS finite element solver were used to analyze the progressive failure of a PMC tensile specimen that initiates at the repeating unit cell (RUC) level. Three different finite element mesh densities were employed and each coupled with an appropriate RUC. Multiple simulations were performed in order to assess the effect of a statistical distribution of fiber strengths on the bulk composite failure and predicted strength. The coupled effects of both the micro- and macroscale discretizations were found to have a noticeable effect on the predicted UTS and computational efficiency of the simulations.

  4. Analytical methods for fissionable material determinations in the nuclear fuel cycle. Progress report, October 1, 1976--September 30, 1977

    International Nuclear Information System (INIS)

    Waterbury, G.R.

    1978-01-01

    Development of dissolution techniques for difficult-to-dissolve nuclear materials, development of methods and automated instruments for plutonium and uranium determinations, preparation of plutonium-containing materials for the Safeguards Analytical Laboratory Evaluation (SALE) program, analysis of SALE uranium materials, preparation of certified reference material plutonium metal, measurement of longer plutonium isotope half-lives, and study of ion exchange behavior of elements in various media continued. Gas-solid reaction of carbonyl chloride with uranium-bearing materials at elevated temperature is superior to reaction with chlorine for uranium volatilization and separation. Neither reaction with a variety of nonaqueous solvents nor reaction with molten selenium oxide provides practical dissolution of refractory materials characteristic of nuclear fuel cycle materials. The LASL automated spectrophotometer has been used to determine 0.1-mg amounts without instrumental or procedural changes. A microgram-sensitive spectrophotometric method for uranium has been developed, and the automated spectrophotometer is being modified to its use. A controlled-potential coulometric method has been developed for selective determination of plutonium. An automated analyzer to use this method is being built. Uranium-plutonium mixed oxide powder, for SALE samples, has not remained stable during storage, but high-density pellets have. In a DOE interlaboratory program, the half-life of 239 Pu has been measured, experiments on 241 Pu half-life measurement are in progress, and 240 Pu half-life measurement is planned. Ion exchange distributions for over 50 elements have been measured to determine cation exchange in nitric acid and anion exchange in both hydrobromic and hydriodic acids

  5. Analytical methods for fissionable material determinations in the nuclear fuel cycle. Progress report, October 1, 1976--September 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Waterbury, G.R. (comp.)

    1978-01-01

    Development of dissolution techniques for difficult-to-dissolve nuclear materials, development of methods and automated instruments for plutonium and uranium determinations, preparation of plutonium-containing materials for the Safeguards Analytical Laboratory Evaluation (SALE) program, analysis of SALE uranium materials, preparation of certified reference material plutonium metal, measurement of longer plutonium isotope half-lives, and study of ion exchange behavior of elements in various media continued. Gas-solid reaction of carbonyl chloride with uranium-bearing materials at elevated temperature is superior to reaction with chlorine for uranium volatilization and separation. Neither reaction with a variety of nonaqueous solvents nor reaction with molten selenium oxide provides practical dissolution of refractory materials characteristic of nuclear fuel cycle materials. The LASL automated spectrophotometer has been used to determine 0.1-mg amounts without instrumental or procedural changes. A microgram-sensitive spectrophotometric method for uranium has been developed, and the automated spectrophotometer is being modified to its use. A controlled-potential coulometric method has been developed for selective determination of plutonium. An automated analyzer to use this method is being built. Uranium-plutonium mixed oxide powder, for SALE samples, has not remained stable during storage, but high-density pellets have. In a DOE interlaboratory program, the half-life of /sup 239/Pu has been measured, experiments on /sup 241/Pu half-life measurement are in progress, and /sup 240/Pu half-life measurement is planned. Ion exchange distributions for over 50 elements have been measured to determine cation exchange in nitric acid and anion exchange in both hydrobromic and hydriodic acids.

  6. Radiation effects on structural materials. Technical progress report, January 1, 1984-June 30, 1984

    International Nuclear Information System (INIS)

    Ghoneim, N.M.

    1984-01-01

    By a generalization of an analysis due to Frank of the growing precipitate, we derive an analytic sink strength for the growing void that takes account of the void surface motion in a self-consistent fashion. The lower mobility of the vacancies compared to the interstitials ensures that a growing void captures more vacancies than the usual quasi-static void. The various consequences of this void bias for vacancies are discussed in relation to the swelling of reactor materials

  7. Enforcement actions: Significant actions resolved material licensees. Semiannual progress report, July--December 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    This compilation summarizes significant enforcement actions that have been resolved during the period and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication.

  8. Metals and Ceramics Division materials science program. Annual progress report for period ending June 30, 1981

    Energy Technology Data Exchange (ETDEWEB)

    McHargue, C.J. (comp.)

    1981-09-01

    Information is presented concerning the theoretical studies of metals and alloys; x-ray diffraction research; structural ceramics; structure of coal; analytical and high-voltage electron microscopy; deformation and mechanical properties; mechanisms of surface and solid-state reactions; physical properties research; metastable materials; neutron radiation effects; charged particle radiation effects; theory and modeling of radiation effects; facility and advanced technique development; fundamentals of welding and joining; and studies in nondestructive evaluation.

  9. Metals and Ceramics Division materials science program. Annual progress report for period ending June 30, 1981

    International Nuclear Information System (INIS)

    McHargue, C.J.

    1981-09-01

    Information is presented concerning the theoretical studies of metals and alloys; x-ray diffraction research; structural ceramics; structure of coal; analytical and high-voltage electron microscopy; deformation and mechanical properties; mechanisms of surface and solid-state reactions; physical properties research; metastable materials; neutron radiation effects; charged particle radiation effects; theory and modeling of radiation effects; facility and advanced technique development; fundamentals of welding and joining; and studies in nondestructive evaluation

  10. Enforcement actions: Significant actions resolved material licensees. Semiannual progress report, July--December 1996

    International Nuclear Information System (INIS)

    1997-04-01

    This compilation summarizes significant enforcement actions that have been resolved during the period and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  11. Recent progress in layered double hydroxide based materials for electrochemical capacitors: design, synthesis and performance.

    Science.gov (United States)

    Zhao, Mingming; Zhao, Qunxing; Li, Bing; Xue, Huaiguo; Pang, Huan; Chen, Changyun

    2017-10-19

    As representative two-dimensional (2D) materials, layered double hydroxides (LDHs) have received increasing attention in electrochemical energy storage and conversion because of the facile tunability between their composition and morphology. The high dispersion of active species in layered arrays, the simple exfoliation into monolayer nanosheets and chemical modification offer the LDHs an opportunity as active electrode materials in electrochemical capacitors (ECs). LDHs are favourable in providing large specific surface areas, good transport features as well as attractive physicochemical properties. In this review, our purpose is to provide a detailed summary of recent developments in the synthesis and electrochemical performance of the LDHs. Their composites with carbon (carbon quantum dots, carbon black, carbon nanotubes/nanofibers, graphene/graphene oxides), metals (nickel, platinum, silver), metal oxides (TiO 2 , Co 3 O 4 , CuO, MnO 2 , Fe 3 O 4 ), metal sulfides/phosphides (CoS, NiCo 2 S 4 , NiP), MOFs (MOF derivatives) and polymers (PEDOT:PSS, PPy (polypyrrole), P(NIPAM-co-SPMA) and PET) are also discussed in this review. The relationship between structures and electrochemical properties as well as the associated charge-storage mechanisms is discussed. Moreover, challenges and prospects of the LDHs for high-performance ECs are presented. This review sheds light on the sustainable development of ECs with LDH based electrode materials.

  12. Research progress in photolectric materials of CuFeS2

    Science.gov (United States)

    Jing, Mingxing; Li, Jing; Liu, Kegao

    2018-03-01

    CuFeS2 as a photoelectric material, there are many advantages, such as high optical absorption coefficient, direct gap semiconductor, thermal stability, no photo-recession effect and so on. Because of its low price, abundant reserves and non-toxic, CuFeS2 has attracted extensive attention of scientists.Preparation method of thin film solar cells are included that Electrodeposition, sputtering, thermal evaporation, thermal spraying method, co-reduction method.In this paper, the development of CuFeS2 thin films prepared by co-reduction method and co-reduction method is introduced.In this paper, the structure and development of solar cells, advantages of CuFeS2 as solar cell material, the structure and photoelectric properties and magnetic properties of CuFeS2, preparation process analysis of CuFeS2 thin film, research and development of CuFeS2 in solar cells is included herein. Finally, the development trend of CuFeS2 optoelectronic materials is analyzed and further research directions are proposed.

  13. Progress report on the accelerator production of tritium materials irradiation program

    Energy Technology Data Exchange (ETDEWEB)

    Maloy, S.A.; Sommer, W.F.; Brown, R.D.; Roberts, J.E. [and others

    1997-05-01

    The Accelerator Production of Tritium (APT) project is developing an accelerator and a spoliation neutron source capable of producing tritium through neutron capture on He-3. A high atomic weight target is used to produce neutrons that are then multiplied and moderated in a blanket prior to capture. Materials used in the target and blanket region of an APT facility will be subjected to several different and mixed particle radiation environments; high energy protons (1-2 GeV), protons in the 20 MeV range, high energy neutrons, and low energy neutrons, depending on position in the target and blanket. Flux levels exceed 10{sup 14}/cm{sup 2}s in some areas. The APT project is sponsoring an irradiation damage effects program that will generate the first data-base for materials exposed to high energy particles typical of spallation neutron sources. The program includes a number of candidate materials in small specimen and model component form and uses the Los Alamos Spallation Radiation Effects Facility (LASREF) at the 800 MeV, Los Alamos Neutron Science Center (LANSCE) accelerator.

  14. Development of FeCoB/Graphene Oxide based microwave absorbing materials for X-Band region

    Energy Technology Data Exchange (ETDEWEB)

    Das, Sukanta [Integrated Test Range (ITR), Chandipur 756025 (India); Indian School of Mines, Dhanbad 826004 (India); Chandra Nayak, Ganesh, E-mail: ganeshnayak2006@gmail.com [Indian School of Mines, Dhanbad 826004 (India); Sahu, S.K. [Integrated Test Range (ITR), Chandipur 756025 (India); Oraon, Ramesh [Indian School of Mines, Dhanbad 826004 (India)

    2015-06-15

    This work explored the microwave absorption capability of Graphene Oxide and Graphene Oxide coated with FeCoB for stealth technology. Epoxy based microwave absorbing materials were prepared with 30% loading of Graphene Oxide, FeCoB alloy and Graphene Oxide coated with FeCoB. Graphene Oxide and FeCoB were synthesized by Hummer's and Co-precipitation methods, respectively. The filler particles were characterized by FESEM, XRD and Vibrating Sample Magnetometer techniques. Permittivity, permeability and reflection loss values of the composite absorbers were measured with vector network analyzer which showed a reflection loss value of −7.86 dB, at 10.72 GHz, for single layered Graphene Oxide/Epoxy based microwave absorbers which can be correlated to the absorption of about 83.97% of the incident microwave energy. Reflection loss value of FeCoB/Epoxy based microwave absorber showed −13.30 dB at 11.67 GHz, which corresponded to maximum absorption of 93.8%. However, reflection loss values of Graphene Oxide coated with FeCoB/Epoxy based single-layer absorber increased to −22.24 dB at 12.4 GHz which corresponds to an absorption of 99% of the incident microwave energy. - Highlights: • FeCoB coated Graphene Oxide (GO) was synthesized by co-precipitation method. • GO, FeCoB and GO@FeCoB based microwave absorbers were developed with Epoxy matrix. • GO and FeCoB/Epoxy absorbers showed −7.86 & −13.30 dB reflection loss, respectively. • Maximum Reflection loss of −22.24 dB was achieved with GO@FeCoB/Epoxy absorber.

  15. Analyzing Students' Learning Progressions Throughout a Teaching Sequence on Acoustic Properties of Materials with a Model-Based Inquiry Approach

    Science.gov (United States)

    Hernández, María Isabel; Couso, Digna; Pintó, Roser

    2015-04-01

    The study we have carried out aims to characterize 15- to 16-year-old students' learning progressions throughout the implementation of a teaching-learning sequence on the acoustic properties of materials. Our purpose is to better understand students' modeling processes about this topic and to identify how the instructional design and actual enactment influences students' learning progressions. This article presents the design principles which elicit the structure and types of modeling and inquiry activities designed to promote students' development of three conceptual models. Some of these activities are enhanced by the use of ICT such as sound level meters connected to data capture systems, which facilitate the measurement of the intensity level of sound emitted by a sound source and transmitted through different materials. Framing this study within the design-based research paradigm, it consists of the experimentation of the designed teaching sequence with two groups of students ( n = 29) in their science classes. The analysis of students' written productions together with classroom observations of the implementation of the teaching sequence allowed characterizing students' development of the conceptual models. Moreover, we could evidence the influence of different modeling and inquiry activities on students' development of the conceptual models, identifying those that have a major impact on students' modeling processes. Having evidenced different levels of development of each conceptual model, our results have been interpreted in terms of the attributes of each conceptual model, the distance between students' preliminary mental models and the intended conceptual models, and the instructional design and enactment.

  16. Review of Recent Progress of Plasmonic Materials and Nano-Structures for Surface-Enhanced Raman Scattering

    Directory of Open Access Journals (Sweden)

    Alan X. Wang

    2015-05-01

    Full Text Available Surface-enhanced Raman scattering (SERS has demonstrated single-molecule sensitivity and is becoming intensively investigated due to its significant potential in chemical and biomedical applications. SERS sensing is highly dependent on the substrate, where excitation of the localized surface plasmons (LSPs enhances the Raman scattering signals of proximate analyte molecules. This paper reviews research progress of SERS substrates based on both plasmonic materials and nano-photonic structures. We first discuss basic plasmonic materials, such as metallic nanoparticles and nano-rods prepared by conventional bottom-up chemical synthesis processes. Then, we review rationally-designed plasmonic nano-structures created by top-down approaches or fine-controlled synthesis with high-density hot-spots to provide large SERS enhancement factors (EFs. Finally, we discuss the research progress of hybrid SERS substrates through the integration of plasmonic nano-structures with other nano-photonic devices, such as photonic crystals, bio-enabled nanomaterials, guided-wave systems, micro-fluidics and graphene.

  17. Characterization of Structural Defects in Wide Band-Gap Compound Materials for Semiconductor and Opto-Electronic Applications

    Science.gov (United States)

    Goue, Ouloide Yannick

    Single crystals of binary and ternary compounds are touted to replace silicon for specialized applications in the semiconductor industry. However, the relative high density of structural defects in those crystals has hampered the performance of devices built on them. In order to enhance the performance of those devices, structurally perfect single crystals must be grown. The aim of this thesis is to investigate the interplay between crystal growth process and crystal quality as well as structural defect types and transport property. To this end, the thesis is divided into two parts. The first part provides a general review of the theory of crystal growth (chapter I), an introduction to the materials being investigated (chapter II and III) and the characterization techniques being used (chapter IV). • In chapter I, a brief description of the theory of crystal growth is provided with an eye towards the driving force behind crystal nucleation and growth along with the kinetic factors affecting crystal growth. The case of crystal growth of silicon carbide (SiC) by physical vapor transport (PVT) and chemical vapor deposition (CVD) is discussed. The Bridgman, travelling heater method (THM) and physical transport growth of cadmium zinc telluride (CZT) is also treated. In chapters II and III, we introduce the compound materials being investigated in this study. While a description of their crystal structure and properties is provided, the issues associated with their growth are discussed. In chapter IV, a description of the characterization techniques used in these studies is presented. These techniques are synchrotron X-ray topography (SXRT), transmission electron microscopy, transmission infrared microscopy (TIM), micro-Raman spectroscopy (muRS) and light microscopy. Extensive treatment of SXRT technique is also provided. In the second part, the experimental results obtained in the course of these studies are presented and discussed. These results are divided into

  18. Enforcement actions: Significant actions resolved material licensees. Quarterly progress report, April 1995--June 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April-June 1995) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication.

  19. Progress in research and regulatory development by the Materials Engineering Branch, RES Engineering Division

    International Nuclear Information System (INIS)

    Serpan, C.Z. Jr.

    1988-01-01

    Much activity has been underway In NRC this past year on definition of aging Issues for nuclear power plants that will be applicable to the regulatory considerations of applications for license renewals following the Initial 40-year operating period. The Materials Engineering Branch has been reviewing its program to assure that aging Issues are prominent, and to identify regulatory documents that will have to be validated or revised to provide a proper basis for license renewal safety evaluation. A report on the branch plan for aging and needs for extended life review is under preparation and should be available early in 1988

  20. Progress report: Chemistry and Materials Division, 1982 April 1 - June 30

    International Nuclear Information System (INIS)

    1982-08-01

    The work of the division in the areas of solid state studies, radiation chemistry, isotope separation, analytical chemistry and materials science is described. The solid state science group studied solute atom vacancy trapping in irradiated f.c.c. alloys as well as the rearrangement of atoms in solids bombarded by energetic heavy ions. In radiation chemistry, work was done on the pulse radiolysis of NO in argon. Isotope separation studies were done on fluoroform and uranium. Fuel burnup determination using 148 Nd and 139 La was investigated. Zirconium alloy studies included work on stress corrosion cracking and the Baushinger effect

  1. Review on the progress of research on functional materials. Superionic conductors: 1997 - 1998

    International Nuclear Information System (INIS)

    Jahja, A.K.; Effendi, Nurdin; Purnama, Safei; Marsongkohadi

    1999-01-01

    For the period of December 1997 - December 1998, two superionic compounds the non-stoichiometric Cu-base Rubidium Copper Iodide Chloride and the silver-based RbAg 4 I 5 were prepared and characterized. In this report some of the result of this cooperation is presented. Activities concerning conductivity and dielectric properties measurement at BATAN laboratory are outlined. Although the high temperature neutron scattering measurements have not been completed until now, a further cooperation involving the preparation and neutron scattering measurements of materials in thin-film and single crystalline morphology is proposed. (author)

  2. Progress of SOFC/SOEC Development at DTU Energy: From Materials to Systems

    DEFF Research Database (Denmark)

    Hagen, Anke; Hendriksen, Peter Vang

    2017-01-01

    DTU Energy has over the past 20 years had a very substantial effort on SOFC/SOEC development. The current project volume corresponds to ~40 man years per year. Activities span over a broad range in the value chain, from materials to cells, stacks and analyses at energy system level. In addition...... to that, research areas comprise ceramic processing methods, micro-structural analysis, electrochemical characterization, and modelling. Among recent highlights are electrode and cell developments, including metal supported cells, stack development durability studies under realistic operation conditions...

  3. Review on the progress of research on functional materials. Superionic conductors: 1997 - 1998

    Energy Technology Data Exchange (ETDEWEB)

    Jahja, A.K.; Effendi, Nurdin; Purnama, Safei [National Atomic Energy Agency, Serpong (Indonesia); Marsongkohadi [Bandung Institute of Technology, Bandung (Indonesia)

    1999-10-01

    For the period of December 1997 - December 1998, two superionic compounds the non-stoichiometric Cu-base Rubidium Copper Iodide Chloride and the silver-based RbAg{sub 4}I{sub 5} were prepared and characterized. In this report some of the result of this cooperation is presented. Activities concerning conductivity and dielectric properties measurement at BATAN laboratory are outlined. Although the high temperature neutron scattering measurements have not been completed until now, a further cooperation involving the preparation and neutron scattering measurements of materials in thin-film and single crystalline morphology is proposed. (author)

  4. Enforcement actions: Significant actions resolved material licensees. Quarterly progress report, April 1995--June 1995

    International Nuclear Information System (INIS)

    1995-08-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April-June 1995) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  5. Helium generation in fusion reactor materials. Technical progress report, October 1976--March 1977

    International Nuclear Information System (INIS)

    Farrar, H. IV; Kneff, D.W.

    1977-01-01

    The immediate objectives of this program are to measure the spectrum-integrated helium generation rates and cross sections of several materials in the available high intensity neutron sources, and to develop neutron dosimetry procedures using some of these materials. This requires further development of foil activation dosimetry techniques, since the cross section measurements require a detailed characterization of each neutron environment. The neutron facilities presently used in this program include accelerators producing d-T and d-Be reactions and high flux mixed-spectrum fission reactors. Most of the work reported here has focused on neutron spectra from the d-T reaction. A description is given of the preliminary analysis of wire rings included in the irradiation capsule for helium accumulation fluence dosimetry. The results show non-uniformities in the neutron fluence distribution characterizing this irradiation, and point out the value of helium accumulation fluence dosimetry for characterizing high energy (approximately 5 to 30 MeV) neutron fields. The helium accumulation fluence data are being used to adjust the neutron fluence map for calculation of final helium generation cross sections from the other RTNS-irradiated pure element specimens. Most of the specimens irradiated in the RTNS-I experiment have been analyzed for helium, and preliminary results are presented

  6. Progress in target materials for high-efficiency X-ray backlight

    International Nuclear Information System (INIS)

    Du Ai; Zhou Bin; Li Longxiang; Zhu Xiurong; Li Yu'nong; Shen Jun; Gao Guohua; Zhang Zhihua; Wu Guangming

    2012-01-01

    The composition, microstructure and density of the target materials are the key parameters to determinate the photon energy and intensity of the laser-induced X-ray backlight. Thus the classification of backlight targets, the preparation of target materials and the interaction between targets and high power laser were introduced in this paper. Underdense targets were more competitive than traditional dense targets among the backlight targets. Nano-structured foam targets, which could be classified into nanofiber targets and aerogel targets, were regarded as novel high-efficiency underdense targets. Nanofiber, which was commonly prepared via electro spinning and thermal treatment, exhibited good formability and high concentration of emission atoms; while aerogel, which was prepared via sol-gel processes and supercritical fluid drying, possesses the advantages of homogeneous microstructure and theoretically high conversion efficiency, but accompanied with the disadvantages of complex synthetic processes and low concentration of emission atoms. To prepare monolithic aerogels with low density and high concentration of emission atoms via combined sol-gel theories may be the better design for the development of the laser-induced X-ray backlight. (authors)

  7. Research progress of cholesteric liquid crystals with broadband reflection characteristics in application of intelligent optical modulation materials

    Science.gov (United States)

    Zhang, Lan-Ying; Gao, Yan-Zi; Song, Ping; Wu, Xiao-Juan; Yuan, Xiao; He, Bao-Feng; Chen, Xing-Wu; Hu, Wang; Guo, Ren-Wei; Ding, Hang-Jun; Xiao, Jiu-Mei; Yang, Huai

    2016-09-01

    Cholesteric liquid crystals (CLCs) have recently sparked an enormous amount of interest in the development of soft matter materials due to their unique ability to self-organize into a helical supra-molecular architecture and their excellent selective reflection of light based on the Bragg relationship. Nowadays, by the virtue of building the self-organized nanostructures with pitch gradient or non-uniform pitch distribution, extensive work has already been performed to obtain CLC films with a broad reflection band. Based on authors’ many years’ research experience, this critical review systematically summarizes the physical and optical background of the CLCs with broadband reflection characteristics, methods to obtain broadband reflection of CLCs, as well as the application in the field of intelligent optical modulation materials. Combined with the research status and the advantages in the field, the important basic and applied scientific problems in the research direction are also introduced. Project supported by the National Natural Science Foundation of China (Grant Nos. 51573006, 51573003, 51203003, 51303008, 51302006, 51402006, 51272026, and 51273022), the Major Project of Beijing Science and Technology Program, China (Grant Nos. Z151100003315023 and Z141100003814011), and the Fok Ying Tung Education Foundation, China (Grant No. 142009).

  8. Progress report Chemistry and Materials Division, 1 April - 30 June, 1980

    International Nuclear Information System (INIS)

    1980-09-01

    By a combination of electrostatic and magnetic deflection it has been possible to examine the yield of ions scattered through 180 0 from the surface region of a variety of solid targets. Progress has been made in establishing a basis for quantitative assay of multiple vacancy clusters around single solute atoms in dilute alloys. HF laser-induced decomposition of 2,2,2,-trifluoroethanol has been studied as a function of laser fluence. The oxidation of carbon monoxide adsorbed on the (111) crystal face of platinum has been investigated further. Vacuum pumping systems of the D/H mass spectrometers have been replaced with turbo-molecular pumping systems, reducing the HD + background five-fold. Three iodine species, I-, I0 3 -, and I0 4 -, have been successfully separated and detected in aqueous solutions in the course of iodine specification studies. It has been shown that the occurrence of groups of grains with preferentially tangential basal poles serves to locate any radial hydrides at the inside surface of Zircaloy fuel cladding, but does not make any additional contribution to the susceptibility of the cladding to iodine induced stress corrosion cracking. The orientation relationships between oxide and metal on the (0001), (1120) and (1010) planes of zirconium single crystals show a different relationship for each of the principal planes. Further studies in the High Voltage Electron Microscope at AERE, Harwell confirm that electron irradiation produces only interstitial loops, and does not introduce -component dislocations in zirconium. The microtome has been improved to the point where layers of a ductile metal (zirconium) down to 70 nm can be reproducibly removed. (auth)

  9. Attenuation by a Human Body and Trees as well as Material Penetration Loss in 26 and 39 GHz Millimeter Wave Bands

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2017-01-01

    Full Text Available This paper investigates the attenuation by a human body and trees as well as material penetration loss at 26 and 39 GHz by measurements and theoretical modeling work. The measurements were carried out at a large restaurant and a university campus by using a time domain channel sounder. Meanwhile, the knife-edge (KE model and one-cylinder and two-cylinder models based on uniform theory of diffraction (UTD are applied to model the shape of a human body and predict its attenuation in theory. The ITU (International Telecommunication Union and its modified models are used to predict the attenuation by trees. The results show that the upper bound of the KE model is better to predict the attenuation by a human body compared with UTD one-cylinder and two-cylinder models at both 26 and 39 GHz. ITU model overestimates the attenuation by willow trees, and a modified attenuation model by trees is proposed based on our measurements at 26 GHz. Penetration loss for materials such as wood and glass with different types and thicknesses is measured as well. The measurement and modeling results in this paper are significant and necessary for simulation and planning of fifth-generation (5G mm-wave radio systems in ITU recommended frequency bands at 26 and 39 GHz.

  10. Progress report, Chemistry and Materials Division 1 July - 30 September, 1981

    International Nuclear Information System (INIS)

    1981-11-01

    The work of the division in the areas of solid state physics, chemistry and materials science over the quarter is described. The solid state science branch has worked on crystal defect formation after ion beam irradiation. Laser isotope separation methods have produced visible amounts of water enriched 2000-fold in deuterium. Work has been done on hydrogen isotope exchange in H 2 -methanol mixtures. Nitrogen impurities in Xe-133 can be determined down to the microgram level. A new apparatus for the determination of hydrogen in zirconium has been assembled. Coatings of stainless steels on zircaloy fuel cladding continue to offer protection against oxidation. Agreement has been obtained between computer-simulated and observed electron microscope images of irradiated titanium. Cold-worked zirconium has been studied under helium ion bombardment

  11. Science of materials progress report, July 1, 1975--June 30, 1976

    International Nuclear Information System (INIS)

    1976-04-01

    Research in Metallurgy and Ceramics included the investigation of the mechanical properties, stress corrosion cracking, and fracture of metals, alloys, and transition metal compounds; the investigation of the dynamic structure of water and electrolyte solutions at high temperature and pressure; and the investigation of the properties of oxides and of the magnetic properties of alloys. Solid state Physics research was focussed on the electronic properties of solids and on defects in crystal structure including radiation damage. Important topics of investigation were the effect of dislocations and impurities on the mechanical properties of metals, diffusion processes in superionic conductors, the defect structure of quantum crystals, high pressure studies of the electronic structure of phosphors, and the magnetic structure of transition metal atoms in nonmagnetic host crystals. The program is planned to provide an atomic understanding of energy flow, conversion and storage processes, and to support with basic research the development of improved materials for energy applications

  12. Science of materials progress report, July 1, 1975--June 30, 1976

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-04-01

    Research in Metallurgy and Ceramics included the investigation of the mechanical properties, stress corrosion cracking, and fracture of metals, alloys, and transition metal compounds; the investigation of the dynamic structure of water and electrolyte solutions at high temperature and pressure; and the investigation of the properties of oxides and of the magnetic properties of alloys. Solid state Physics research was focussed on the electronic properties of solids and on defects in crystal structure including radiation damage. Important topics of investigation were the effect of dislocations and impurities on the mechanical properties of metals, diffusion processes in superionic conductors, the defect structure of quantum crystals, high pressure studies of the electronic structure of phosphors, and the magnetic structure of transition metal atoms in nonmagnetic host crystals. The program is planned to provide an atomic understanding of energy flow, conversion and storage processes, and to support with basic research the development of improved materials for energy applications.

  13. Progress in heavy-fermion superconductivity. Ce115 and related materials

    International Nuclear Information System (INIS)

    Thompson, Joe D.; Fisk, Zachary

    2012-01-01

    Ce115 and related Ce compounds are particularly suited to detailed studies of the interplay of antiferromagnetic order, unconventional superconductivity and quantum criticality due to their availability as high quality single crystals and their tunability by chemistry, pressure and magnetic field. Neutron-scattering, NMR and angle-resolved thermodynamic measurements have deepened the understanding of this interplay. Very low temperature experiments in pure and lightly doped CeCoIn 5 have elaborated the FFLO-like magnetic state near the field-induced quantum-critical point. New, related superconducting materials have broadened the phase space for discovering underlying principles of heavy-fermion superconductivity and its relationship to nearby states. (author)

  14. Progress with alloy 33 (UNS R20033), a new corrosion resistant chromium-based austenitic material

    International Nuclear Information System (INIS)

    Koehler, M.; Heubner, U.; Eichenhofer, K.W.; Renner, M.

    1996-01-01

    Alloy 33 (UNS R20033), a new chromium-based corrosion resistant austenitic material with nominally (wt. %) 33 Cr, 32 Fe, 31 Ni, 1.6 Mo, 0.6 Cu, 0.4 N has been introduced to the market in 1995. This paper provides new data on this alloy with respect to mechanical properties, formability, weldability, sensitization characteristics and corrosion behavior. Mechanical properties of weldments including ductility have been established, and match well with those of wrought plate material, without any degradation of ISO V-notch impact toughness in the heat affected zone. When aged up to 8 hours between 600 C and 1,000 C the alloy is not sensitized when tested in boiling azeotropic nitric acid (Huey test). Under field test conditions alloy 33 shows excellent resistance to corrosion in flowing 96--98.5% H 2 SO 4 at 135 C--140 C and flowing 99.1% H 2 SO 4 at 150 C. Alloy 33 has also been tested with some success in 96% H 2 SO 4 with nitrosyl additions at 240 C. In nitric acid alloy 33 is corrosion resistant up to 85% HNO 3 and 75 C or even more. Alloy 33 is also corrosion resistant in 1 mol. HCl at 40 C and in NaOH/NaOCl-solutions. In artificial seawater the pitting potential remains unchanged up to 75 C and is still well above the seawater's redox potential at 95 C. Alloy 33 can be easily manufactured into all product forms required. The new data provided support the multipurpose character of alloy 33 to cope successfully with many requirements of the Chemical Process Industry, the Oil and Gas Industry and the Refinery Industry

  15. Progress towards materials science above 1000 GPa (10 Mbar) on the NIF laser

    International Nuclear Information System (INIS)

    Remington, B.A.; Park, H.; Prisbrey, S.T.; Pollaine, S.M.; Cavallo, R.M.; Rudd, R.E.; Lorenz, K.T.; Becker, R.; Bernier, J.; Barton, N.; Arsenlis, T.; Glendinning, S.G.; Hamza, A.; Swift, D.; Jankowski, A.; Meyers, M.A.

    2009-01-01

    Solid state dynamics experiments at extreme pressures, P > 1000 GPa (10 Mbar), and ultrahigh strain rates (1.e6-1.e8 1/s) are being developed for the National Ignition Facility (NIF) laser. These experiments will open up exploration of new regimes of materials science at an order of magnitude higher pressures than have been possible to date. Such extreme, solid state conditions can be accessed with a ramped pressure drive. The experimental, computational, and theoretical techniques are being developed and tested on the Omega laser. Velocity interferometer measurements (VISAR) establish the high pressure conditions generated by the ramped drive. Constitutive models for solid state strength under these conditions are tested by comparing simulations with experiments measuring perturbation growth from the Rayleigh-Taylor instability in solid state samples of vanadium. Radiography techniques using synchronized bursts of x-rays have been developed to diagnose this perturbation growth. Experiments on Omega demonstrating these techniques at peak pressures of ∼1 Mbar will be discussed. The time resolved observation of foil cracking and void formation show the need for tamped samples and a planar drive

  16. Progress report, Chemistry and Materials Division: 1982 October 1 -December 31

    International Nuclear Information System (INIS)

    1983-02-01

    Solid state studies included work on the trapping vacancies of Au atoms by the backscattering-channeling method, and investigation into mixing across interfaces resulting from heavy ion bombardment. In radiation chemistry, computer simulations of nitrogen atom yield from radiolysis of N 2 -O 2 mixtures were found to agree with experiment. Surface science research included studies of temporal oscillations in the kinetics of oxidation of carbon monoxide over the (100) face of single-crystal platinum. In analytical chemistry, research projects included the determination of thorium-230 in ores, use of a high specific activity methyl bromide tracer in commercial applications, determination of burnup in (Th,U)0 2 fuels using HPLC, and development of a simple and quick means to determine D 2 0 content of water grab samples at CANDU sites using a small soft-bulb hydrometer. Materials science studies included experiments on true incubation time for stress-corrosion cracking in iodine vapour, examination of hydrogen contents of fuel cladding from bundles with failed pins, and studies of initiation of ΣnodularΣ corrosion of fuel cladding in high-temperature steam

  17. Progress report, Chemistry and Materials Division: 1982 July 1 - September 30

    International Nuclear Information System (INIS)

    1982-10-01

    During the third quarter of 1982, work in solid state studies included study of energy spectra of Auger electrons from a silicon single crystal, use of an excimer laser to anneal an aluminum crystal implanted with iron atoms, studies of defects created by helium ion irradiation of a dilute copper-indium alloy crystal, and computer simulations of ion channeling in a platinum crystal surface. Work in radiation chemistry on the enhancement of water calorimetry sensitivity continued. A surface science program to understand the temporal oscillations in the oxidation of carbon monoxide over platinum continued with the study of the interaction of oxygen with the (100) crystallographic face of platinum. Studies in analytical chemistry included a comparison of fuel burnup results using 145 Nd + 146 Nd and 148 Nd, and a preliminary investigation into methods of reduction of U(VI) to U(IV), particularly electrolytic reduction. Materials science work continued on the fracture surfaces of Exel alloys cracked in hydrogen gas, the true incubation time for stress corrosion cracking in cesium-cadmium vapour mixtures, evidence for a previously unknown hexagonal phase of germanium, growth experiments in the DIDO reactor on swaged single-crystals, and examination of the first zirconium specimen purified by electrotransport in the CRNL equipment

  18. Materials recycle and waste management in fusion power reactors. Progress report for 1982

    International Nuclear Information System (INIS)

    Vogler, S.; Jung, J.; Steindler, M.J.; Maya, I.; Levine, H.E.; Peterman, D.D.; Strausburg, S.; Schultz, K.R.

    1983-01-01

    Several components of a STARFIRE fusion reactor have been studied. The breeding ratios were calculated as a function of lithium enrichment and neutron multiplier for systems containing either Li 2 O or LiAlO 2 . The lithium requirements for a fusion economy were also estimated for those cases and the current US resources were found to be adequate. However, competition with other lithium demands in the future emphasizes the need for recovering and reusing lithium. The radioactivities induced in the breeder and the impurities responsible for their formation were determined. The residual radioactivities of several low-activation structural materials were compared with the radioactivity from the prime candidate alloy (PCA) a titanium modified Type 316 stainless steel used in STARFIRE. The impurities responsible for the radioactivity levels were identified. From these radioactive impurity levels it was determined that V15Cr5Ti could meet the requirements for shallow land burial as specified by the Nuclear Regulatory Commission (10CFR61), whereas PCA would require a more restrictive disposal mode, i.e. in a geologic medium. The costs for each of these disposal modes were then estimated

  19. Progress report, Chemistry and Materials Division, 1 April - 30 June, 1981

    International Nuclear Information System (INIS)

    1981-08-01

    The work of the Division in the areas of solid state science, radiation, physical and analytical chemistry, and materials science during the quarter is described. Measurements of ion stopping power have emphasized the importance of axial symmetry and may be used to show the contribution of nuclear inelastic events to stopping processes. Enhancement of ion scattering at 180 degrees can occur even in the first few layers of a single crystal of gold implanted with heavy atoms. Agreement has been obtained between experimental and calculated rates for dechanneling of protons in gold. The rate of decomposition of HOI in aqueous solutions has been determined. The effects of radiation on dithiothreitol is being studied. Laser photochemistry work includes investigations of multiphoton dissociation and of laser-induced zirconium isotope separation. A method has been found for the preparation of oxygen gas samples for the determination of oxygen isotope ratios in water, and high-performance liquid chromatography has been applied to metals in ground water. Sputtered coatings of stainless steel on the surface of zircaloy fuel cladding reduce the oxidation rate in steam. A theoretically-based design equation for irradiation growth of pressure tubes has been developed. Studies on the effect of small strains on zircaloy-2 tubing show the need to avoid even small amounts of compressive deformation of calandria tubes

  20. Recent Progress in Synthesis and Application of Low-Dimensional Silicon Based Anode Material for Lithium Ion Battery

    Directory of Open Access Journals (Sweden)

    Yuandong Sun

    2017-01-01

    Full Text Available Silicon is regarded as the next generation anode material for LIBs with its ultra-high theoretical capacity and abundance. Nevertheless, the severe capacity degradation resulting from the huge volume change and accumulative solid-electrolyte interphase (SEI formation hinders the silicon based anode material for further practical applications. Hence, a variety of methods have been applied to enhance electrochemical performances in terms of the electrochemical stability and rate performance of the silicon anodes such as designing nanostructured Si, combining with carbonaceous material, exploring multifunctional polymer binders, and developing artificial SEI layers. Silicon anodes with low-dimensional structures (0D, 1D, and 2D, compared with bulky silicon anodes, are strongly believed to have several advanced characteristics including larger surface area, fast electron transfer, and shortened lithium diffusion pathway as well as better accommodation with volume changes, which leads to improved electrochemical behaviors. In this review, recent progress of silicon anode synthesis methodologies generating low-dimensional structures for lithium ion batteries (LIBs applications is listed and discussed.

  1. Recent Progress on the Key Materials and Components for Proton Exchange Membrane Fuel Cells in Vehicle Applications

    Directory of Open Access Journals (Sweden)

    Cheng Wang

    2016-07-01

    Full Text Available Fuel cells are the most clean and efficient power source for vehicles. In particular, proton exchange membrane fuel cells (PEMFCs are the most promising candidate for automobile applications due to their rapid start-up and low-temperature operation. Through extensive global research efforts in the latest decade, the performance of PEMFCs, including energy efficiency, volumetric and mass power density, and low temperature startup ability, have achieved significant breakthroughs. In 2014, fuel cell powered vehicles were introduced into the market by several prominent vehicle companies. However, the low durability and high cost of PEMFC systems are still the main obstacles for large-scale industrialization of this technology. The key materials and components used in PEMFCs greatly affect their durability and cost. In this review, the technical progress of key materials and components for PEMFCs has been summarized and critically discussed, including topics such as the membrane, catalyst layer, gas diffusion layer, and bipolar plate. The development of high-durability processing technologies is also introduced. Finally, this review is concluded with personal perspectives on the future research directions of this area.

  2. Wide band gap materials and devices for NO{sub x}, H{sub 2} and O{sub 2} gas sensing applications

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Majdeddin

    2008-01-22

    In this thesis, field effect gas sensors (Schottky diodes, MOS capacitors, and MOSFET transistors) based on wide band gap semiconductors like silicon carbide (SiC) and gallium nitride (GaN), as well as resistive gas sensors based on indium oxide (In{sub 2}O{sub 3}), have been developed for the detection of reducing gases (H{sub 2}, D{sub 2}) and oxidising gases (NO{sub x}, O{sub 2}). The development of the sensors has been performed at the Institute for Micro- and Nanoelectronic, Technical University Ilmenau in cooperation with (GE) General Electric Global Research (USA) and Umwelt-Sensor- Technik GmbH (Geschwenda). Chapter 1: serves as an introduction into the scientific fields related to this work. The theoretical fundamentals of solid-state gas sensors are provided and the relevant properties of wide band gap materials (SiC and GaN) are summarized. In chapter 2: The performance of Pt/GaN Schottky diodes with different thickness of the catalytic metal were investigated as hydrogen gas detectors. The area as well as the thickness of the Pt were varied between 250 {proportional_to} 250 {mu}m{sup 2} and 1000 {proportional_to} 1000 {mu}m{sup 2}, 8 and 40 nm, respectively. The response to hydrogen gas was investigated in dependence on the active area, the Pt thickness and the operating temperature for 1 vol.% hydrogen in synthetic air. We observed a significant increase of the sensitivity and a decrease of the response and recovery times by increasing the temperature of operation to about 350{sup o}C and by decreasing the Pt thickness down to 8 nm. Electron microscopy of the microstructure showed that the thinner platinum had a higher grain boundary density. The increase in sensitivity with decreasing Pt thickness points to the dissociation of molecular hydrogen on the surface, the diffusion of atomic hydrogen along the platinum grain boundaries and the adsorption of hydrogen at the Pt/GaN interface as a possible mechanism of sensing hydrogen by Schottky diodes. The

  3. Presentation on the Modeling and Educational Demonstrations Laboratory Curriculum Materials Center (MEDL-CMC): A Working Model and Progress Report

    Science.gov (United States)

    Glesener, G. B.; Vican, L.

    2015-12-01

    Physical analog models and demonstrations can be effective educational tools for helping instructors teach abstract concepts in the Earth, planetary, and space sciences. Reducing the learning challenges for students using physical analog models and demonstrations, however, can often increase instructors' workload and budget because the cost and time needed to produce and maintain such curriculum materials is substantial. First, this presentation describes a working model for the Modeling and Educational Demonstrations Laboratory Curriculum Materials Center (MEDL-CMC) to support instructors' use of physical analog models and demonstrations in the science classroom. The working model is based on a combination of instructional resource models developed by the Association of College & Research Libraries and by the Physics Instructional Resource Association. The MEDL-CMC aims to make the curriculum materials available for all science courses and outreach programs within the institution where the MEDL-CMC resides. The sustainability and value of the MEDL-CMC comes from its ability to provide and maintain a variety of physical analog models and demonstrations in a wide range of science disciplines. Second, the presentation then reports on the development, progress, and future of the MEDL-CMC at the University of California Los Angeles (UCLA). Development of the UCLA MEDL-CMC was funded by a grant from UCLA's Office of Instructional Development and is supported by the Department of Earth, Planetary, and Space Sciences. Other UCLA science departments have recently shown interest in the UCLA MEDL-CMC services, and therefore, preparations are currently underway to increase our capacity for providing interdepartmental service. The presentation concludes with recommendations and suggestions for other institutions that wish to start their own MEDL-CMC in order to increase educational effectiveness and decrease instructor workload. We welcome an interuniversity collaboration to

  4. Screened coulomb hybrid DFT investigation of band gap and optical absorption predictions of CuVO3, CuNbO3 and Cu 5Ta11O30 materials

    KAUST Repository

    Harb, Moussab

    2014-01-01

    We present a joint theoretical and experimental investigation of the optoelectronic properties of CuVO3, CuNbO3 and Cu 5Ta11O30 materials for potential photocatalytic and solar cell applications. In addition to the experimental results obtained by powder X-ray diffraction and UV-Vis spectroscopy of the materials synthesized under flowing N2 gas at atmospheric pressure via solid-state reactions, the electronic structure and the UV-Vis optical absorption coefficient of these compounds are predicted with high accuracy using advanced first-principles quantum methods based on DFT (including the perturbation theory approach DFPT) within the screened coulomb hybrid HSE06 exchange-correlation formalism. The calculated density of states are found to be in agreement with the UV-Vis diffuse reflectance spectra, predicting a small indirect band gap of 1.4 eV for CuVO3, a direct band gap of 2.6 eV for CuNbO3, and an indirect (direct) band gap of 2.1 (2.6) eV for Cu5Ta 11O30. It is confirmed that the Cu(i)-based multi-metal oxides possess a strong contribution of filled Cu(i) states in the valence band and of empty d0 metal states in the conduction band. Interestingly, CuVO3 with its predicted small indirect band gap of 1.4 eV shows the highest absorption coefficient in the visible range with a broad absorption edge extending to 886 nm. This novel result offers a great opportunity for this material to be an excellent candidate for solar cell applications. © the Partner Organisations 2014.

  5. Evaluation of caries progression in dentin treated by fluoride-containing materials using an in-air micro-PIGE and micro-PIXE measurement system

    International Nuclear Information System (INIS)

    Yamamoto, H.; Iwami, Y.; Yagi, K.; Hayashi, M.; Komatsu, H.; Okuyama, K.; Matsuda, Y.; Yasuda, K.

    2015-01-01

    It is well-known that fluorine (F) is involved in the progression of caries. The evaluation of caries progression has conventionally been based on the change in mineral content using transverse microradiography (TMR). The purpose of this study was to evaluate the progression of dentinal caries by the change in calcium (Ca) content using Particle-Induced Gamma-ray Emission/Particle-Induced X-ray Emission (PIGE/PIXE) techniques at the Wakasa Wan Energy Research Center. We also assessed the relationship between caries progression rate and the concentration of F penetration into dentin from dental fluoride-containing materials (FCMs). Dentin sections of six extracted human teeth were prepared to obtain various amounts of F uptake using three types of FCMs. F and Ca distribution of specimens were obtained using PIGE/PIXE techniques. After evaluation, the specimens were immersed in 10 ml of demineralizing solution (pH 4.5) to simulate caries attack. To estimate caries progression rates, the same portions of the specimens were evaluated after caries attack treatment using PIGE/PIXE. A negative correlation between the F uptake in dentin and the rate of caries progression was observed. Therefore, caries progression in dentin was reduced by increasing the amount of F uptake from FCMs. This demonstrates that PIGE/PIXE techniques are valuable for estimating caries progression rates

  6. Evaluation of caries progression in dentin treated by fluoride-containing materials using an in-air micro-PIGE and micro-PIXE measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, H., E-mail: yhiroko@dent.osaka-u.ac.jp [Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Iwami, Y.; Yagi, K.; Hayashi, M. [Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Komatsu, H.; Okuyama, K.; Matsuda, Y. [Graduate School of Dental Medicine, Hokkaido University, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586 (Japan); Yasuda, K. [The Wakasa Wan Energy Research Center, 64-52-1 Nagatani, Tsuruga 914-0192 (Japan)

    2015-04-01

    It is well-known that fluorine (F) is involved in the progression of caries. The evaluation of caries progression has conventionally been based on the change in mineral content using transverse microradiography (TMR). The purpose of this study was to evaluate the progression of dentinal caries by the change in calcium (Ca) content using Particle-Induced Gamma-ray Emission/Particle-Induced X-ray Emission (PIGE/PIXE) techniques at the Wakasa Wan Energy Research Center. We also assessed the relationship between caries progression rate and the concentration of F penetration into dentin from dental fluoride-containing materials (FCMs). Dentin sections of six extracted human teeth were prepared to obtain various amounts of F uptake using three types of FCMs. F and Ca distribution of specimens were obtained using PIGE/PIXE techniques. After evaluation, the specimens were immersed in 10 ml of demineralizing solution (pH 4.5) to simulate caries attack. To estimate caries progression rates, the same portions of the specimens were evaluated after caries attack treatment using PIGE/PIXE. A negative correlation between the F uptake in dentin and the rate of caries progression was observed. Therefore, caries progression in dentin was reduced by increasing the amount of F uptake from FCMs. This demonstrates that PIGE/PIXE techniques are valuable for estimating caries progression rates.

  7. An open labeled, comparative clinical study on efficacy and tolerability of oral minipulse of steroid (OMP alone, OMP with PUVA and broad / narrow band UVB phototherapy in progressive vitiligo

    Directory of Open Access Journals (Sweden)

    Rath Namita

    2008-01-01

    Full Text Available Background: Several modalities of treatment have been tried in vitiligo with varied results; however, Indian data on comparative studies of two or more therapies are limited. Aims: We compared different phototherapy methods with an oral steroid as an adjunct to determine the method with the best tolerability and efficacy. Methods: Eighty-six patients with progressive vitiligo were randomly assigned to different study groups according to a continuous selection method over a period of one year. Group 1 was given OMP + PUVA, group 2 OMP + UVB (NB, group 3 OMP + UVB (BB and group 4 was given OMP alone. Each patient was followed up for six months and then released from treatment. Clinical evaluation was made at the end of three and six months. Results: In group 1 (OMP + PUVA, marked improvement was seen in 18.51% while moderate improvement was seen in 66.66% of the patients. Marked improvement was seen in 37.03% in group 2 (OMP + NB-UVB while 44.44% had moderate improvement. In group 3 (OMP + BB UVB, 8.33% showed marked improvement while moderate improvement was seen in 25% of the patients. Marked and moderate improvement was seen in 5 and 10% of group 4 (OMP patients, respectively. Conclusions: Our study compared four treatment modalities in vitiligo patients, out of which oral minipulse of steroids (OMP only had an adjunct value and was not very effective by itself. Narrow band UVB has a definite edge over broad band UVB and should be preferred when both options are available. NB-UVB and PUVA showed comparable efficacy.

  8. SINGLE-BAND, TRIPLE-BAND, OR MULTIPLE-BAND HUBBARD MODELS

    NARCIS (Netherlands)

    ESKES, H; SAWATZKY, GA

    1991-01-01

    The relevance of different models, such as the one-band t-J model and the three-band Emery model, as a realistic description of the electronic structure of high-T(c) materials is discussed. Starting from a multiband approach using cluster calculations and an impurity approach, the following

  9. Influence of band offset, nanostructuring, and applied electric field on the optoelectronic properties of vertically stacked MoS2/WS2 materials

    Science.gov (United States)

    Mlinar, Vladan

    2017-12-01

    We theoretically investigate the electronic and optical properties of multilayer vertically stacked MoS2/WS2 heterostructures, focusing on the role of the MoS2-WS2 band offset, number of monolayers in the heterostructure, effects of an applied electric field, and size reduction in lateral direction, leading to MoS2/WS2 -based nanowires and nanoplatelets. Given that different values of the MoS2-WS2 band offset have been reported, we show that the band offset determines the ordering of the energy levels in the valence band and spin projections at the K point of the Brillouin zone. These variations as function of the value of the band offset are suppressed in an external electric field. For multilayer MoS2/WS2 -based nanostructures, our calculations reveal nanowires and nanoplatelets with S-atom edges exhibit a metallic character, but nanowires with one S-atom and other Mo/W edge show the band gap with electrons located in MoS2 and holes in WS2 layer. The band gap can be controlled by the size of the nanowire in lateral direction and number of layers. The calculated real part of optical conductivity show that the lowest optical transitions originate from the optical transitions in MoS2 layers. The electronic structure is obtained from a parametrized tight-binding model that includes nonorthogonal sp 3d5 orbitals and spin orbit coupling. Our results are gauged with respect to those extracted from density functional theory and G W methods to ensure the high quality of our predictions.

  10. Materials testing and requirement for the ERDA nuclear-powered artificial heart. Technical progress report, July 15, 1975--May 30, 1976

    International Nuclear Information System (INIS)

    Andrade, J.D.; Hufferd, W.L.; Lyman, D.J.

    1976-01-01

    The two materials currently being used for the artificial heart fabrication are BIOMER and AVCOTHANE. BIOMER is a polyether urethane polymer. AVCOTHANE is a proprietary polyurethane/polydimethylsiloxane polymer blend. Research progress on the chemical degradation, mechanical strength, and blood compatibility is reported

  11. Progress report on nuclear science and technology in China (Vol.1). Proceedings of academic annual meeting of China Nuclear Society in 2009, No.4--nuclear material

    International Nuclear Information System (INIS)

    2010-11-01

    Progress report on nuclear science and technology in China (Vol. 1) includes 889 articles which are communicated on the first national academic annual meeting of China Nuclear Society. There are 10 books totally.This is the fourth one, the content is about nuclear materials, isotope separation, nuclear chemistry and radiological chemistry.

  12. Materials testing and requirement for the ERDA nuclear-powered artificial heart. Technical progress report, July 15, 1975--May 30, 1976. [BIOMER and AVCOTHANE

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, J. D.; Hufferd, W. L.; Lyman, D. J.

    1976-01-01

    The two materials currently being used for the artificial heart fabrication are BIOMER and AVCOTHANE. BIOMER is a polyether urethane polymer. AVCOTHANE is a proprietary polyurethane/polydimethylsiloxane polymer blend. Research progress on the chemical degradation, mechanical strength, and blood compatibility is reported. (TFD)

  13. Development of small-bore, high-current-density railgun as testbed for study of plasma-materials interaction. Progress report for October 16, 2000 - May 13, 2003

    International Nuclear Information System (INIS)

    Kyekyoon, Kim-Kevin

    2003-01-01

    The present document is a final technical report summarizing the progress made during 10/16/2000 - 05/13/2003 toward the development of a small-bore railgun with transaugmentation as a testbed for investigating plasma-materials interaction

  14. Low band gap polymers for organic photovoltaics

    DEFF Research Database (Denmark)

    Bundgaard, Eva; Krebs, Frederik C

    2007-01-01

    Low band gap polymer materials and their application in organic photovoltaics (OPV) are reviewed. We detail the synthetic approaches to low band gap polymer materials starting from the early methodologies employing quinoid homopolymer structures to the current state of the art that relies...... in photovoltaic applications and give a tabular overview of rarely applied materials....

  15. Recent progresses and achievements in photovoltaic-phase change material technology: A review with special treatment on photovoltaic thermal-phase change material systems

    International Nuclear Information System (INIS)

    Islam, M.M.; Pandey, A.K.; Hasanuzzaman, M.; Rahim, N.A.

    2016-01-01

    Highlights: • Broad summary of phase change materials based cooling for photovoltaic modules. • Compendium on phase change materials that are mostly used in photovoltaic systems. • Extension of heat availability period by 75–100% with phase change material. • Heat storage potential improves by 33–50% more with phase change material. • Future trend and move in photovoltaic thermal research. - Abstract: This communication lays out an appraisal on the recent works of phase change materials based thermal management techniques for photovoltaic systems with special focus on the so called photovoltaic thermal-phase change material system. Attempt has also been made to draw wide-ranging classification of both photovoltaic and photovoltaic thermal systems and their conventional cooling or heat harvesting methods developed so far so that feasible phase change materials application area in these systems can be pointed out. In addition, a brief literature on phase change materials with particular focus on their solar application has also been presented. Overview of the researches and studies establish that using phase change materials for photovoltaic thermal control is technically viable if some issues like thermal conductivity or phase stability are properly addressed. The photovoltaic thermal-phase change material systems are found to offer 33% (maximum 50%) more heat storage potential than the conventional photovoltaic-thermal water system and that with 75–100% extended heat availability period and around 9% escalation in output. Reduction in temperature attained with photovoltaic thermal-phase change material system is better than that with regular photovoltaic-thermal water system, too. Studies also show the potential of another emerging technology of photovoltaic thermal-microencapsulated phase change material system that makes use of microencapsulated phase change materials in thermal regulation. Future focus areas on photovoltaic thermal-phase change

  16. Gas-Cooled Reactor Programs annual progress report for period ending December 31, 1973. [HTGR fuel reprocessing, fuel fabrication, fuel irradiation, core materials, and fission product distribution; GCFR fuel irradiation and steam generator modeling

    Energy Technology Data Exchange (ETDEWEB)

    Kasten, P.R.; Coobs, J.H.; Lotts, A.L.

    1976-04-01

    Progress is summarized in studies relating to HTGR fuel reprocessing, refabrication, and recycle; HTGR fuel materials development and performance testing; HTGR PCRV development; HTGR materials investigations; HTGR fuel chemistry; HTGR safety studies; and GCFR irradiation experiments and steam generator modeling.

  17. Band gap engineering of Cu3FexSn(1-x)S4: A potential absorber material for solar energy

    Science.gov (United States)

    Nazari, P.; Yazdani, A.; Shadrokh, Z.; Abdollahi Nejand, B.; Farahani, N.; Seifi, R.

    2017-12-01

    In this work, band gap engineering of quaternary chalcogenides with the general formula of Cu2FexSn(1-x)S4 was conducted by substituting Sn atoms with Fe atoms. The morphology and crystalline structure of the synthesized nanostructured powder were studied by field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD), respectively. Optical properties of the nanostructured powder were studied by UV-Vis spectroscopy. The results indicate that substitution of Sn atoms with Fe atoms could transfer the tetragonal structure of CTS to tetragonal CFTS structure. The 1.54 eV band gap reached in 80 at.% replacement of Sn atoms with Fe atoms resulting in a tetragonal Cu2FeSnS4 flower-like structure. Moreover, by loading smaller amount of Fe atoms up to 20 at.%, no Fe atoms incorporation in CTS structure was observed.

  18. Materials

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2009-02-01

    Full Text Available community. The construction industry is a significantly consumer of materials, using 50 per cent of all products produced globally. Building materials is any material which is used for a construction purpose. Many of these materials are sources from natural...

  19. Fossil Energy Advanced Research and Technology Development Materials Program. Semiannual progress report for the period ending September 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Cole, N.C.; Judkins, R.R. [comps.

    1992-12-01

    Objective of this materials program is to conduct R and D on materials for fossil energy applications with focus on longer-term and generic needs of the various fossil fuel technologies. The projects are organized according to materials research areas: (1) ceramics, (2) new alloys: iron aluminides, advanced austenitics and chromium niobium alloys, and (3) technology development and transfer. Separate abstracts have been prepared.

  20. Hazardous materials in aquatic environments of the Mississippi River Basin. Quarterly progress report, July 1, 1995--September 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    This report is the quarterly progress report for July through September 1995 for work done by Tulane and Xavier Universities under DOE contract number DE-FG01-93-EW53023. Accomplishments for various tasks including administrative activities, collaborative cluster projects, education projects, initiation projects, coordinated instrumentation facility, and an investigators` retreat are detailed in the report.

  1. Semiconductors bonds and bands

    CERN Document Server

    Ferry, David K

    2013-01-01

    As we settle into this second decade of the twenty-first century, it is evident that the advances in micro-electronics have truly revolutionized our day-to-day lifestyle. The technology is built upon semiconductors, materials in which the band gap has been engineered for special values suitable to the particular application. This book, written specifically for a one semester course for graduate students, provides a thorough understanding of the key solid state physics of semiconductors. It describes how quantum mechanics gives semiconductors unique properties that enabled the micro-electronics revolution, and sustain the ever-growing importance of this revolution.

  2. HYBASE : HYperspectral BAnd SElection

    NARCIS (Netherlands)

    Schwering, P.B.W.; Bekman, H.H.P.T.; Seijen, H.H. van

    2009-01-01

    Band selection is essential in the design of multispectral sensor systems. This paper describes the TNO hyperspectral band selection tool HYBASE. It calculates the optimum band positions given the number of bands and the width of the spectral bands. HYBASE is used to assess the minimum number of

  3. Analytical methods for fissionable material determinations in the nuclear fuel cycle. Progress report, October 1, 1978-September 30, 1979

    International Nuclear Information System (INIS)

    Waterbury, G.R.

    1980-03-01

    Work continues on the development of dissolution techniques for difficult-to-dissolve nuclear materials, the development of methods and automated instruments for plutonium, uranium, and thorium determinations, and the preparation of plutonium materials for the Safeguards Analytical Laboratory Evaluation (SALE) program and distribution by the National Bureau of Standards (NBS) as standard reference materials (SRMs). We are measuring the loner plutonium isotope half-lives, evaluating the isotope correlation techniques and the chemistry involved in the mass-spectrometric ion-bead techniques, and analyzing the SALE uranium materials. Completed subtasks include evaluations of various Teflon materials to recommend those acceptable for the dissolution apparatus developed at LASL, investigations of laser-enhanced dissolution of refractory materials, determinations of diverse ion effects on the microgram-sensitive method for determining uranium, fabrication of the first automated controlled-potential coulometric analyzer for determining plutonium, preparation of a 244 Pu material for distribution by NBS as a SRM, and determination of the half-life of 239 Pu. Work has been started on a spectrophotometric method for determining microgram quantities of plutonium, a microcomplexometric titration method for determining uranium, the use of new reagents for separations of plutonium, the preparation and packaging of a new lot of high-purity plutonium metal for distribution by NBS as a plutonium chemical SRM, and determination of half-lives of other plutonium isotopes

  4. Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, January 1, 1978--March 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    1978-06-26

    The activities associated with the procurement of the materials for the screening test program, information from vendor certification for the materials received, and preliminary information from the materials characterization tests performed by GE are reported. The construction status of the simulated reactor helium supply system, testing equipment, and gas chemistry analysis instrumentation and equipment are discussed. The final recommended impurity levels for the screening phase helium are presented and the rational behind this gas chemistry is discussed. The status of the data management system is presented.

  5. Chemistry and Materials Science progress report, first half FY 1992. Weapons-Supporting Research and Laboratory Directed Research and Development

    Energy Technology Data Exchange (ETDEWEB)

    1992-07-01

    This report contains sections on: Fundamentals of the physics and processing of metals; interfaces, adhesion, and bonding; energetic materials; plutonium research; synchrotron radiation-based materials science; atomistic approach to the interaction of surfaces with the environment: actinide studies; properties of carbon fibers; buried layer formation using ion implantation; active coherent control of chemical reaction dynamics; inorganic and organic aerogels; synthesis and characterization of melamine-formaldehyde aerogels; structural transformation and precursor phenomena in advanced materials; magnetic ultrathin films, surfaces, and overlayers; ductile-phase toughening of refractory-metal intermetallics; particle-solid interactions; electronic structure evolution of metal clusters; and nanoscale lithography induced chemically or physically by modified scanned probe microscopy.

  6. Efficient many-body calculations for two-dimensional materials using exact limits for the screened potential: Band gaps of MoS2, h-BN, and phosphorene

    DEFF Research Database (Denmark)

    Rasmussen, Filip Anselm; Schmidt, Per Simmendefeldt; Winther, Kirsten Trøstrup

    2016-01-01

    Calculating the quasiparticle (QP) band structure of two-dimensional (2D) materials within the GW self-energy approximation has proven to be a rather demanding computational task. The main reason is the strong q dependence of the 2D dielectric function around q = 0 that calls for a much denser sa...... gap of the three prototypical 2D semiconductors, MoS2, h-BN, and phosphorene, including the effect of self-consistency at the GW0 level. The method is implemented in the open source code GPAW....

  7. Ultrafast Charge and Triplet State Formation in Diketopyrrolopyrrole Low Band Gap Polymer/Fullerene Blends: Influence of Nanoscale Morphology of Organic Photovoltaic Materials on Charge Recombination to the Triplet State

    Directory of Open Access Journals (Sweden)

    René M. Williams

    2017-01-01

    Full Text Available Femtosecond transient absorption spectroscopy of thin films of two types of morphologies of diketopyrrolopyrrole low band gap polymer/fullerene-adduct blends is presented and indicates triplet state formation by charge recombination, an important loss channel in organic photovoltaic materials. At low laser fluence (approaching solar intensity charge formation characterized by a 1350 nm band (in ~250 fs dominates in the two PDPP-PCBM blends with different nanoscale morphologies and these charges recombine to form a local polymer-based triplet state on the sub-ns timescale (in ~300 and ~900 ps indicated by an 1100 nm absorption band. The rate of triplet state formation is influenced by the morphology. The slower rate of charge recombination to the triplet state (in ~900 ps belongs to a morphology that results in a higher power conversion efficiency in the corresponding device. Nanoscale morphology not only influences interfacial area and conduction of holes and electrons but also influences the mechanism of intersystem crossing (ISC. We present a model that correlates morphology to the exchange integral and fast and slow mechanisms for ISC (SOCT-ISC and H-HFI-ISC. For the pristine polymer, a flat and unstructured singlet-singlet absorption spectrum (between 900 and 1400 nm and a very minor triplet state formation (5% are observed at low laser fluence.

  8. R&D of Novel Materials for Animal Litters Using High Carbon Fly Ash Final Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Boxley, Chett J. [Ceramatec, Inc., Salt Lake City, UT (United States); Kadota, Rod [Ceramatec, Inc., Salt Lake City, UT (United States)

    2012-10-29

    This research program performed by Ceramatec may significantly increase the beneficial utilization of fly ash, and improve the overall performance of high quality animal litter products. Ceramatec has developed a novel high surface area material, which is capable of ammonia adsorption. High surface area zeolites when combined with agglomerated fly ash can significantly reduce the use of naturally mined materials (i.e. clay bentonite) for animal litter manufacture. This not only preserves natural resources and the natural environment, but it also will reduce CO2 emissions, via the reduced need for heavy mining equipment. This novel animal litter is made with over 85% of recycled materials, thus preventing their disposition to landfills. The novel litter material is similar to traditional clay-like litters, and it is clumpable and has superior odor control properties.

  9. Analytical methods for fissionable material determinations in the nuclear fuel cycle. Progress report, October 1, 1977--September 30, 1978

    International Nuclear Information System (INIS)

    Waterbury, G.R.

    1979-01-01

    Work has continued on the development of dissolution techniques for difficult-to-dissolve nuclear materials, development of methods and automated instruments for plutonium and uranium determinations, preparation of plutonium-containing materials for the Safeguards Analytical Laboratory Evaluation (SALE) program, preparation of plutonium materials for distribution by the National Bureau of Standards (NBS) as standard reference materials (SRMs), measurement of longer plutonium isotope half-lives, and analysis of SALE uranium materials. New tasks include the development of methods and automated instruments for the determination of thorium and uranium, and an evaluation of the ion-exchange-bead technique for the mass spectrometric measurement of uranium and plutonium isotope distributions. Completed tasks include the measurements of ion exchange distributions of over 50 elements on cation exchange resins from nitric acid media and anion exchange resins from hydrobromic and hydriodic acid media. Using a newly developed procedure, the LASL automated spectrophotometer was modified to determine microgram levels of uranium and to determine milligram levels of uranium and plutonium. Construction of an automated controlled-potential analyzer for the determination of plutonium is nearing completion. Apparatus and procedures for the separation and complexometric titration of thorium and uranium are being developed

  10. Heavy vehicle propulsion system materials program semi-annual progress report for October 1997 through March 1998

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.

    1998-06-01

    The purpose of the Heavy Vehicle Propulsion System materials Program is the development of materials: ceramics, intermetallics, metal alloys, and metal and ceramic coatings, to support the dieselization of class 1--3 trucks to realize a 35{percent} fuel-economy improvement over current gasoline-fueled trucks and to support commercialization of fuel-flexible LE-55 low-emissions, high-efficiency diesel engines for class 7--8 trucks. The Office of Transportation Technologies, Office of Heavy Vehicle Technologies (OTT OHVT) has an active program to develop the technology for advanced LE-55 diesel engines with 55{percent} efficiency and low emissions levels of 2.0 g/bhp-h NO{sub x} and 0.05 g/bhp-h particulates. The goal is also for the LE-55 engine to run on natural gas with efficiency approaching that of diesel fuel. The LE-55 program is being completed in FY 1997 and, after approximately 10 years of effort, has largely met the program goals of 55{percent} efficiency and low emissions. However, the commercialization of the LE-55 technology requires more durable materials than those that have been used to demonstrate the goals. Heavy Vehicle Propulsion System Materials will, in concert with the heavy-duty diesel engine companies, develop the durable materials required to commercialize the LE-55 technologies.

  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. Band-in-band segregation of multidisperse granular mixtures

    NARCIS (Netherlands)

    Newey, M.; Ozik, J.; van der Meer, S.M.

    2004-01-01

    Radial and axial segregation is investigated experimentally in polydisperse mixtures of granular materials rotated in a long, partly filled, horizontal cylinder. Radial segregation by size is observed in all polydisperse mixtures. Axial segregation, with smaller-size particles forming bands within

  13. Atomic-Monolayer MoS2 Band-to-Band Tunneling Field-Effect Transistor

    KAUST Repository

    Lan, Yann Wen

    2016-09-05

    The experimental observation of band-to-band tunneling in novel tunneling field-effect transistors utilizing a monolayer of MoS2 as the conducting channel is demonstrated. Our results indicate that the strong gate-coupling efficiency enabled by two-dimensional materials, such as monolayer MoS2, results in the direct manifestation of a band-to-band tunneling current and an ambipolar transport.

  14. The dynamics of a shear band

    Science.gov (United States)

    Giarola, Diana; Capuani, Domenico; Bigoni, Davide

    2018-03-01

    A shear band of finite length, formed inside a ductile material at a certain stage of a continued homogeneous strain, provides a dynamic perturbation to an incident wave field, which strongly influences the dynamics of the material and affects its path to failure. The investigation of this perturbation is presented for a ductile metal, with reference to the incremental mechanics of a material obeying the J2-deformation theory of plasticity (a special form of prestressed, elastic, anisotropic, and incompressible solid). The treatment originates from the derivation of integral representations relating the incremental mechanical fields at every point of the medium to the incremental displacement jump across the shear band faces, generated by an impinging wave. The boundary integral equations (under the plane strain assumption) are numerically approached through a collocation technique, which keeps into account the singularity at the shear band tips and permits the analysis of an incident wave impinging a shear band. It is shown that the presence of the shear band induces a resonance, visible in the incremental displacement field and in the stress intensity factor at the shear band tips, which promotes shear band growth. Moreover, the waves scattered by the shear band are shown to generate a fine texture of vibrations, parallel to the shear band line and propagating at a long distance from it, but leaving a sort of conical shadow zone, which emanates from the tips of the shear band.

  15. Chemistry and materials science progress report. Weapons-supporting research and laboratory directed research and development: FY 1995

    International Nuclear Information System (INIS)

    1996-04-01

    This report covers different materials and chemistry research projects carried out a Lawrence Livermore National Laboratory during 1995 in support of nuclear weapons programs and other programs. There are 16 papers supporting weapons research and 12 papers supporting laboratory directed research

  16. Chemistry and materials science progress report. Weapons-supporting research and laboratory directed research and development: FY 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    This report covers different materials and chemistry research projects carried out a Lawrence Livermore National Laboratory during 1995 in support of nuclear weapons programs and other programs. There are 16 papers supporting weapons research and 12 papers supporting laboratory directed research.

  17. Efficient use of energy and materials: progress and policies. A report of the Secretary-General of the United Nations

    International Nuclear Information System (INIS)

    1996-01-01

    There is growing awareness of the serious problems associated with the provision of sufficient energy to meet human needs and to fuel economic growth world-wide. This has pointed to the need for energy and material efficiency, which would reduce air, water and thermal pollution, as well as waste production. Increasing energy and material efficiency also have the benefits of increased employment, improved balance of imports and exports, increased security of energy supply and adopting environmentally advantageous energy supply. A large potential exists for energy savings through energy and material efficiency improvements. Technologies are not now, nor will they be, in the foreseeable future, the limiting factors with regard to continuing energy efficiency improvements. There are serious barriers to energy efficiency improvements, including unwillingness to invest, lack of available and accessible information, economic disincentives and organizational barriers. A wide range of policy instruments, as well as innovative approaches have been tried in some countries in order to achieve the desired energy efficiency improvements. These include: regulation and guidelines; economic instruments and incentives; voluntary agreements and actions; information, education and training; and research, development and demonstration. An area that requires particular attention is that of improved international co-operation to develop policy instruments and technologies to meet the needs of developing countries. Material efficiency has not received the attention that it deserves. Consequently, there is a dearth of data on the qualities and quantities of final consumption, thus, making it difficult to formulate policies. Available data, however, suggest that there is a large potential for improved use of many materials in industrialized countries. (author). 1 fig

  18. Evaluation of Platinum Silicide and Indium Antimonide as Detector Materials for Space-Based Remote Sensing in the 3.0-to-5.0 Micrometer Wavelength Band

    Science.gov (United States)

    1989-12-01

    Reflectance Alkyd Resin .181 Epoxy Resin .614 Lacquer Resin .615 Nylon Resin .277 Polyurethane Resin .608 Polyvinyl Chloride Resin .921 Titanium Dioxide .108...Atmospheric Propagation of IR Radiation 6 MWIR Characteristics............... Sensors................... Sensitivity........... ... . .. ... 1 Photon...material. x I. Introduction Space-based infrared ( IR ) remote sensing has been in existence for over 29 years - almost from the days following the _irst

  19. X-ray magnetic circular dichroism in d and f ferromagnetic materials: recent theoretical progress. Part II

    International Nuclear Information System (INIS)

    Antonov, V.N.; Shpak, A.P.; Yares'ko, A.N.

    2008-01-01

    The present state of theoretical understanding of the x-ray magnetic circular dichroism (XMCD) of 4f and 5f compounds is reviewed. Energy band theory based upon the local spin-density approximation (LSDA) describes the XMCD spectra of transition metal compounds with high accuracy. However, the LSDA does not suffice for lanthanide compounds which have a correlated 4f shell. A satisfactory description of the XMCD spectra could be obtained by using a generalization of the LSDA, in which explicitly f electron Coulomb correlations are taken into account (LSDA+U approach). As examples of this group we consider the compound GdN. We also consider uranium 5f compounds. In those compounds where the 5f electrons are rather delocalized, the LSDA describes the XMCD spectra reasonably well. As an example of this group we consider UFe 2 . Particular differences occur for uranium compounds in which the 5f electrons are neither delocalized nor localized, but more or less semilocalized. Typical examples are UXAl (X=Co, Rh, and Pt), and UX (X=S, Se, Te). However, the semilocalized 5f's are not inert, but their interaction with conduction electrons plays an important role. We also consider the electronic structure and XMCD spectra of the heavy-fermion compounds UPt 3 , URu 2 Si 2 , UPd 2 Al 3 , UNi 2 Al 3 , and UBe 13 , where the degree of the 5f localization is increased in comparison with other uranium compounds. The electronic structure and XMCD spectra of UGe 2 which possesses simultaneously ferromagnetism and superconductivity also presented. Recently achieved improvements for describing 5f compounds are discussed

  20. Recent progress in advanced optical materials based on gadolinium aluminate garnet (Gd3Al5O12)

    Science.gov (United States)

    Li, Ji-Guang; Sakka, Yoshio

    2015-02-01

    This review article summarizes the recent achievements in stabilization of the metastable lattice of gadolinium aluminate garnet (Gd3Al5O12, GAG) and the related developments of advanced optical materials, including down-conversion phosphors, up-conversion phosphors, transparent ceramics, and single crystals. Whenever possible, the materials are compared with their better known YAG and LuAG counterparts to demonstrate the merits of the GAG host. It is shown that novel emission features and significantly improved luminescence can be attained for a number of phosphor systems with the more covalent GAG lattice and the efficient energy transfer from Gd3+ to the activator. Ce3+ doped GAG-based single crystals and transparent ceramics are also shown to simultaneously possess the advantages of high theoretical density, fast scintillation decay, and high light yields, and hold great potential as scintillators for a wide range of applications. The unresolved issues are also pointed out.

  1. Radiation effects on materials in the near-field of nuclear waste repository. 1998 annual progress report

    International Nuclear Information System (INIS)

    Ewing, R.C.; Wang, L.M.

    1998-01-01

    'Site restoration activities at DOE facilities and the permanent disposal of nuclear waste generated at DOE facilities involve working with and within various types and levels of radiation fields. Once the nuclear waste is incorporated into a final form, radioactive decay will decrease the radiation field over geologic time scales, but the alpha-decay dose for these solids will still reach values as high as 10 18 alpha-decay events/gm in periods as short as 1,000 years. This dose is well within the range for which important chemical (e.g., increased leach rate) and physical (e.g., volume expansion) changes may occur in crystalline ceramics. Release and sorption of long-lived actinides (e.g., 237 Np) can provide a radiation exposure to backfill materials, and changes in important properties (e.g., cation exchange capacity) may occur. The objective of this research program is to evaluate the long term radiation effects in the materials in the near-field of a nuclear waste repository with accelerated experiments in the laboratory using energetic particles (electrons, ions and neutrons). Experiments on the microstructural evolution during irradiation of two important groups of materials, sheet silicates (e.g., clays) and zeolites (analcime), have been conducted; and studies of radiation-induced changes in chemical properties (e.g. cation exchange capacity) are underway. As of the mid-2nd year of the 3-year project, experiments on the microstructural evolution during irradiation of two important group of materials, sheet silicates (mica) and zeolites (analcime), have been conducted; and studies of radiation-induced changes in chemical properties (e.g., cation exchange capacity) are underway.'

  2. Azlactone-Functionalized Polymers as Reactive Platforms for the Design of Advanced Materials: Progress in the Last Ten Years.

    Science.gov (United States)

    Buck, Maren E; Lynn, David M

    2012-01-01

    Polymers functionalized with azlactone (or oxazolone) functionality have become increasingly useful for the rapid and modular design of functional materials. Because azlactones can react via ring-opening reactions with a variety of different nucleophilic species (e.g., primary amines, hydroxyl groups, and thiol functionality), azlactone-functionalized materials can serve as convenient 'reactive' platforms for the post-synthesis or post-fabrication introduction of a broad range of chemical functionality to soluble polymers, insoluble supports, and surfaces/interfaces. The last decade has seen an increase in both the number and the variety of reports that exploit the properties and the reactivities of azlactone-functionalized polymers. Here, we highlight recent work from several different laboratories, including our own, toward the design and characterization of azlactone-functionalized polymers, with a particular emphasis on: (i) new synthetic approaches for the preparation of well-defined azlactone-functionalized polymers using living/controlled methods of polymerization, (ii) the design and modular synthesis of side-chain functionalized polymers and block copolymers via post-polymerization modification of azlactone-functionalized polymers, (iii) the development of reactive polymeric supports useful in the contexts of separations and catalysis, and (iv) methods for the fabrication of reactive thin films and other approaches to the immobilization of azlactone functionality on surfaces and interfaces. Examples discussed herein reveal a growing awareness of azlactone functionality as a useful tool for polymer chemists, and highlight several ways that the unique reactivity of these materials can both complement and provide useful alternatives to other reactive polymers currently used to design functional materials.

  3. Progress in mass spectrometry for the analysis of set-off phenomena in plastic food packaging materials.

    Science.gov (United States)

    Aznar, Margarita; Alfaro, Pilar; Nerín, Cristina; Jones, Emrys; Riches, Eleanor

    2016-07-01

    In most cases, food packaging materials contain inks whose components can migrate to food by diffusion through the material as well as by set-off phenomena. In this work, different mass spectrometry approaches had been used in order to identify and confirm the presence of ink components in ethanol (95%) and Tenax(®) as food simulants. Three different sets of materials, manufactured with different printing technologies and with different structures, were analyzed. Sample analysis by ultra performance liquid chromatography mass spectrometry (UPLC-MS), using a quadrupole-time of flight (Q-TOF) as a mass analyser proved to be an excellent tool for identification purposes while ion mobility mass spectrometry (IM-MS) shown to be very useful for the confirmation of the candidates proposed. The results showed the presence of different non-volatile ink components in migration such as colorants (Solvent Red 49), plasticizers (dimethyl sebacate, tributyl o-acetyl citrate) or surfactants (SchercodineM, triethylene glycol caprilate). An oxidation product of an ink additive (triphenyl phosphine oxide) was also detected. In addition, a surface analysis technique, desorption electrospray mass spectrometry (DESI-MS), was used for analyzing the distribution of some ink components (tributyl o-acetyl citrate Schercodine L, phthalates) in the material. The detection of some of these compounds in the back-printed side confirmed the transference of this compound from the non-food to the food contact side. The results also showed that concentration of ink migrants decreased when an aluminum or polypropylene layer covered the ink. When aluminum was used, concentration of most of ink migrants decreased, and for 5 out of the 9 even disappeared. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Long-Term Properties of Cement-Based Composites Incorporating Natural Zeolite as a Feature of Progressive Building Material

    Directory of Open Access Journals (Sweden)

    Alena Sičáková

    2017-01-01

    Full Text Available This study is aimed at the utilization of natural zeolite as a prospective type of Supplementary Cementitious Material in connection with the innovations of construction solutions through the materials. The influence of zeolite on several properties of cement-based composites is studied. Basic characteristics of input powdery materials as well as the technological parameters of zeolite tested on mortar containing 50% of cement replacement are presented. The technical parameters of concrete containing 8, 13, and 25% of cement replacement by zeolite are presented as well. The paper is valuable due to the three-year testing period. The density of the hardened concrete was found to be decreasing with increasing zeolite content. While no significant differences in compressive strength were found after 28 days, differences between individual samples were clear after the long-term period. The presence of zeolite influenced the compressive strength positively in the case of the 8% and 13% replacement, while the higher proportion of natural zeolite (25% caused lower compressive strength after 28 days but was similar to the reference concrete after three years. A major increase in strength was detected for all samples in the long-term period. It confirms the long-term potential of zeolite for strength improvement.

  5. Corrosion behaviour of container materials for geological disposal of high-level waste. Joint annual progress report 1983

    International Nuclear Information System (INIS)

    1985-01-01

    Within the framework of the Community R and D programme on management and storage of radioactive waste (shared-cost action), a research activity is aiming at the assessment of corrosion behaviour of potential container materials for geological disposal of vitrified high-level wastes. In this report, the results obtained during the year 1983 are described. Research performed at the Studiecentrum voor Kernenergie/Centre d'Etudes de l'Energie Nucleaire (SCK/CEN) at Mol (B), concerns the corrosion behaviour in clay environments. The behaviour in salt is tested by the Kernforschungszentrum (KfK) at Karlsruhe (D). Corrosion behaviour in granitic environments is being examined by the Commissariat a l'Energie Atomique (CEA) at Fontenay-aux-Roses (F) and the Atomic Energy Research Establishment (AERE) at Harwell (UK); the first is concentrating on corrosion-resistant materials and the latter on corrosion-allowance materials. Finally, the Centre National de la Recherche Scientifique (CNRS) at Vitry (F) is examining the formation and behaviour of passive layers on the metal alloys in the various environments

  6. Overview of recent progress on the DARPA/USAF Wright Laboratory Smart Materials and Structures Development--Smart Wing program

    Science.gov (United States)

    Kudva, Jayanth N.; Appa, Kari; Jardine, A. Peter; Martin, Christopher A.; Carpenter, Bernie F.

    1997-05-01

    The concept of an adaptive aircraft wing, i.e., whose shape parameters such as camber, span-wise twist, and thickness can be varied to optimize the wing shape for various flight conditions, has been extensively studied by numerous researchers. While the aerodynamic benefits (in terms of increased lift/drag ratios, improved maneuverability, and delayed flow separation) have been analytically and experimentally established, the complexity and weight penalty of the designs and actuation using smart materials could potentially alleviate the shortcomings of prior designs, leading the way to a more practical `smart' adaptive wing which responds to changes in flight and environmental conditions by optimally modifying its shape. A summary of recent work in the area of adaptive wing concepts incorporating smart structures technologies is presented. Emphasis is placed on continuing research at Northrop Grumman under a United States Defense Advanced Research Projects Agency contract entitled `Smart Structures and Materials Development-Smart Wing,'. Limitations and potential benefits of adaptive wing designs, applications and advantages of smart material actuators and sensors, and results of recent tests are discussed. Recommendations for future work required to develop an operational smart adaptive wing are also outlined.

  7. Investigation of novel electrode materials for electrochemically based remediation of high and low-level mixed wastes in the DOE complex. 1997 annual progress report

    International Nuclear Information System (INIS)

    Anderson, M.A.; Lewis, N.S.

    1997-01-01

    'This work is focused on the preparation of novel electrode materials for the degradation of toxic wastes in the DOE complex. One of the goals of this work is to characterize whether it is possible to use controlled doping of TiO 2 with species such as Nb in order to create new electrode materials that will facilitate the destruction of undesirable organics and inorganics, without light and instead only with an applied potential, in the waste tanks at the DOE sites. In the first part of this project, the authors have therefore spent an extensive amount of effort characterizing, as a baseline, the chemical and electrochemical behavior of TiO 2 itself, so that they can make robust comparisons to the behavior of the Nb-doped systems in subsequent work on this project. The preparation of these electrode films is being performed by Marc Anderson at Wisconsin, who is preparing a number of different stoichiometries, grain sizes, etc. for investigation of their electrochemical properties by the Lewis group at Caltech. First they report on the progress of the electrode preparation work, and then they describe progress on the electrochemical work.'

  8. Enforcement actions: Significant actions resolved, material licensees. Semiannual progress report, July--December 1997; Volume 16, Number 2, Part 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-04-01

    This compilation summarizes significant enforcement actions that have been resolved during the period (July--December 1997) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication.

  9. Enforcement actions: Significant actions resolved material licensees (non-medical). Quarterly progress report, October 1994--December 1994

    International Nuclear Information System (INIS)

    1995-02-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October - December 1994) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees (non-medical) with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  10. Enforcement actions: Significant actions resolved material licensees (non-medical). Quarterly progress report, October 1994--December 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-02-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October - December 1994) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees (non-medical) with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication.

  11. Enforcement actions: Significant actions resolved, material licensees. Semiannual progress report, July--December 1997; Volume 16, Number 2, Part 3

    International Nuclear Information System (INIS)

    1998-04-01

    This compilation summarizes significant enforcement actions that have been resolved during the period (July--December 1997) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  12. Progress in the Development of a High Power Helicon Plasma Source for the Materials Plasma Exposure Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Goulding, Richard Howell [ORNL; Caughman, John B. [ORNL; Rapp, Juergen [ORNL; Biewer, Theodore M. [ORNL; Bigelow, Tim S. [ORNL; Campbell, Ian H. [ORNL; Caneses Marin, Juan F. [ORNL; Donovan, David C. [ORNL; Kafle, Nischal [ORNL; Martin, Elijah H. [ORNL; Ray, Holly B. [ORNL; Shaw, Guinevere C. [ORNL; Showers, Melissa A. [ORNL

    2017-09-01

    Proto-MPEX is a linear plasma device being used to study a novel RF source concept for the planned Material Plasma Exposure eXperiment (MPEX), which will address plasma-materials interaction (PMI) for nuclear fusion reactors. Plasmas are produced using a large diameter helicon source operating at a frequency of 13.56 MHz at power levels up to 120 kW. In recent experiments the helicon source has produced deuterium plasmas with densities up to ~6 × 1019 m–3 measured at a location 2 m downstream from the antenna and 0.4 m from the target. Previous plasma production experiments on Proto-MPEX have generated lower density plasmas with hollow electron temperature profiles and target power deposition peaked far off axis. The latest experiments have produced flat Te profiles with a large portion of the power deposited on the target near the axis. This and other evidence points to the excitation of a helicon mode in this case.

  13. STUDI BANDING PELAPISAN MATERIAL SKD11 DENGAN METODE PHYSICAL VAPOUR DEPOSITION DAN THERMAL DIFUSION PADA KOMPONEN INSERT DIES MESIN STAMPING PRESS

    Directory of Open Access Journals (Sweden)

    Robertus Suryo Bisono

    2017-02-01

    Full Text Available Telah dilakukan pelapisan menggunakan Titanium Alumunium Nitrid (TIAlN dengan metode PVD Coating (Physical Vapour Diposition dan TD (Thermal Difusion  untuk perlakuan permukaan baja perkakas SKD11 sebagai material Insert Die komponen mesin Stamping Press setelah perlakuan hardening. Perlakuan permukaan dimaksudkan untuk meningkatkan kualitas permukaan khususnya kekerasan dan perubahan struktur mikro yang terjadi. Untuk mengetahui tingkat keberhasilan dari perlakuan permukaan tersebut dilakukan dengan memvariasi waktu proses, masing masing 2 sample diproses pada 4 jam, 5 jam dan 6 jam dengan temperatur  proses masing-masing  400ᴼ C. Kemudian satu dari tiap variable sample tersebut di panaskan pada suhu 1000ᴼ C selama 1 jam, pendinginan dilalukan dengan udara bebas tanpa proses quenching Untuk mengetahui hasilnya dilakukan uji kekerasan mikro Vickers, pengamatan struktur mikro Scanning Eectron Microscope (SEM, dan pengujian komposisi dengan Energy Defersif Sepectroscopy (EDS untuk mengetahui tingkat penyerapan material terdifusi. Hasil menunjukan bahwa SKD11 yang dilapisi TiAlN dengan metode PVD selama 6 jam menghasilkan lapisan yang paling keras yaitu 1363 HV dengan ketebalan lapisan 5,3µm. Proses pemanasan 1000⁰C selama 1 jam pada sample mengakibatkan penurunan kekerasan sample dan lapisan permukaan sample menjadi lebih tebal hingga 50µm. Penambahan lapisan diakibatkan oleh terdifusinya atom atom yang menyusun lapisan TiAlN ke dalam substrat serta keluarnya atom atom penyusun lapisan hingga membentuk lapisan kompleks.

  14. Progress in nano-electro optics characterization of nano-optical materials and optical near-field interactions

    CERN Document Server

    Ohtsu, Motoichi

    2005-01-01

    This volume focuses on the characterization of nano-optical materials and optical-near field interactions. It begins with the techniques for characterizing the magneto-optical Kerr effect and continues with methods to determine structural and optical properties in high-quality quantum wires with high spatial uniformity. Further topics include: near-field luminescence mapping in InGaN/GaN single quantum well structures in order to interpret the recombination mechanism in InGaN-based nano-structures; and theoretical treatment of the optical near field and optical near-field interactions, providing the basis for investigating the signal transport and associated dissipation in nano-optical devices. Taken as a whole, this overview will be a valuable resource for engineers and scientists working in the field of nano-electro-optics.

  15. Characteristic investigation of 2D photonic crystals with full material anisotropy under out-of-plane propagation and liquid-crystal-filled photonic-band-gap-fiber applications using finite element methods.

    Science.gov (United States)

    Hsu, Sen-ming; Chang, Hung-chun

    2008-12-22

    To effectively investigate the fundamental characteristics of two-dimensional (2D) photonic crystals (PCs) with arbitrary 3D material anisotropy under the out-of-plane wave propagation, we establish a full-vectorial finite element method based eigenvalue algorithm to perform related analysis correctly. The band edge diagrams can be conveniently constructed from the band structures of varied propagation constants obtained from the algorithm, which is helpful for the analysis and design of photonic ban gap (PBG) fibers. Several PCs are analyzed to demonstrate the correctness of this numerical model. Our analysis results for simple PCs are checked with others' ones using different methods, including the transfer matrix method, the finite-difference frequency-domain (FDFD) method, and the plane-wave expansion method. And the validity of those for the most complex PC with arbitrary 3D anisotropy is supported by related liquid-crystal-filled PBG fiber mode analysis, which demonstrates the dependence of transmission properties on the PBGs, employing a full-vectorial finite element beam propagation method (FE-BPM).

  16. Maximizing band gaps in plate structures

    DEFF Research Database (Denmark)

    Halkjær, Søren; Sigmund, Ole; Jensen, Jakob Søndergaard

    2006-01-01

    Band gaps, i.e., frequency ranges in which waves cannot propagate, can be found in elastic structures for which there is a certain periodic modulation of the material properties or structure. In this paper, we maximize the band gap size for bending waves in a Mindlin plate. We analyze an infinite...

  17. Complex band structure and electronic transmission eigenchannels

    DEFF Research Database (Denmark)

    Jensen, Anders; Strange, Mikkel; Smidstrup, Soren

    2017-01-01

    molecular junctions. The molecular junctions show that both the length dependence of the total transmission and the individual transmission eigenvalues can be, almost always, found through the complex band structure. The complex band structure of the semi-conducting material, however, does not predict...

  18. Interactions of low-power photons with natural opals—PBG materials, photonic control, natural metamaterials, spontaneous laser emissions, and band-gap boundary responses

    International Nuclear Information System (INIS)

    Four views of each of the opal research specimens in white light (for in-article or cover), in the same order as the specimens depicted in Fig. 3 of the main manuscript. A.On the left: 1.5 carat oval cabochon precious fire opal. B.In the center: 2.5 carats faceted fancy shield precious fire contra luz with mild adularescence. C.On the right: 5.0 carats round cabochon precious crystal opal with blue adularescence. Highlights: ► Emission of micro-lasers from microspheroid cluster boundary zones (quantum dots). ► Lasers illuminated or fluoresced the intra-opal structures of microspheroid photonic glass clusters. ► Microspheroid boundaries are durable to low power light sources. ► Display of previously unknown low power photonic optic properties. ► The research specimens are natural metamaterials. - Abstract: One overall goal of this research was to examine types of naturally-occurring opals that exhibit photonic control to learn about previously-unknown properties of naturally occurring photonic control that may be developed for broader applications. Three different photon sources were applied consecutively to three different types of natural, flawless, gem-quality precious opals. Two photon sources were lasers (green and red) and one was simulated daylight tungsten white. As each type of precious opal was exposed to each of the photon sources, the respective refractions, reflections, and transmissions were studied. This research is the first to show that applying various pleochroic and laser photon sources to these types of opals revealed significant information regarding naturally occurring photonic control, metamaterials, spontaneous laser emissions, and microspheroid cluster (inter-PBG zone) boundary effects. Plus, minimizing ambient light and the use of low power photon sources were critical to observing the properties regarding this photonic materials research. This research yielded information applicable to the development of materials to advance

  19. A general method for the recovery of pure powder XRD patterns from complex mixtures using no a priori information Application of band-target entropy minimization (BTEM) to materials characterization of inorganic mixtures

    International Nuclear Information System (INIS)

    Guo Liangfeng; Kooli, Fethi; Garland, Marc

    2004-01-01

    The recovery of pure component spectra from multi-component mixtures is one of the most common analytical problems in the chemical sciences. In cases where separation of the unknown components is not possible, the problem is often intractable. In materials science research, X-ray diffraction (XRD) and particularly X-ray powder diffraction (XRPD) are perhaps the primary characterization tools. Recently, we introduced band-target entropy minimization (BTEM), an essentially model-free deconvolution technique, applicable to sets of unknown mixture samples and initially applied to liquid-phase characterization (Chew et al., Organometallics, 2002, 21, 1982-1990). In the present study, a set of 12 unknown inorganic powder mixtures were prepared and the XRPD patterns measured. BTEM was then applied. The analysis provided the right prediction that five components were present. Outstanding pure component XRD patterns were obtained for all five components (Pb 3 (PO 4 ) 2 , Pb 3 (PO 4 ) 3 Cl, ZrO 2 , Pb(OH) 2 , and PbO) present. These results have implications for a large variety of intrinsically inseparable multi-component mixtures encountered in material science research. These include un-reactive as well as reactive systems, and ex situ as well as in situ studies, involving organic, inorganic and even metallic/alloy components. Initial tests suggest that BTEM may be well suited for recovering the trace component diffraction patterns present and hence greatly aiding material characterization

  20. Technical Division quarterly progress report, October 1--December 31, 1977. [Fuel cycle research and development; special materials production

    Energy Technology Data Exchange (ETDEWEB)

    Slansky, C.M. (ed.)

    1978-02-01

    Results are presented on the fluidized-bed calcination of simulated radioactive waste from the reprocessing of spent commercial nuclear fuel and on the removal of actinide elements from the waste prior to calcination. Other programs include the development of storage technology for /sup 85/Kr waste; and the behavior of volatile radionuclides during the combustion of HTGR graphite-based fuel. The long-term management of defense waste from the ICPP covers post-calcination treatment of ICPP calcined waste; the removal of actinide elements from first-cycle raffinate; the retrieval and handling of calcined waste from ICPP storage vaults; and the preparation of the Programmatic Environmental Impact Statement on ICPP waste. Process improvements are reported on the Fluorinel headend process for Zircaloy-clad fuels and on uranium accountability measurements. Other development results cover the process for recovering spent Rover fuel, buried pipeline transfer systems, support to the Waste Management Program, Waste Calcining Facility support, New Waste Calcining Facility support, and effluent monitoring methods evaluation and development. In this category are studies on nuclear materials security, application of a liquid-solid fluidized-bed heat exchanger to the recovery of geothermal heat, inplant reactor source term measurements, burnup methods for fast breeder reactor fuels, absolute thermal fission yield measurements, analytical support to light water breeder reactor development, research on analytical methods, and the behavior of environmental species of iodine.

  1. Synthesis of Submicron Hexagonal Plate-Type SnS2 and Band Gap-Tuned Sn1−xTixS2 Materials and Their Hydrogen Production Abilities on Methanol/Water Photosplitting

    Directory of Open Access Journals (Sweden)

    Kang Min Kim

    2014-01-01

    Full Text Available SnS2 and Sn1−xTixS2 (x = 0, 0.1, 0.3, 0.5, and 0.7 mol materials were designed using solvothermal method with the aim to enhance hydrogen production from water/methanol water photosplitting. Scanning electron microscopy revealed hexagonal plates with one side, 3.0 μm in length, in the SnS2 materials. Pure SnS2 showed absorption band edges of above 660 nm, and the absorption was shifted to low wavelengths with the insertion of Ti ions. The evolution of H2 from MeOH/H2O (1 : 1 photosplitting over SnS2 hexagonal plates in the photocatalytic liquid system was 0.016 mL h−1 g−1, and the evolutions were enhanced in Sn1−xTixS2. In particular, 0.049 mL h−1 g−1 of H2 gas was produced in Sn0.7Ti0.3S2 without electrolytes and it increased significantly to more than 90.6% (0.47 mL h−1 g−1 evolutions at higher pH using 0.1 M of KOH. Based on the UV-visible absorption spectra, the high photocatalytic activity of Sn1−xTixS2 was attributed to the existence of an appropriate band-gap state that retarded recombination between the electrons and holes.

  2. Broadened band C-telecom and intense upconversion emission of Er{sup 3+}/Yb{sup 3+} co-doped CaYAlO{sub 4} luminescent material obtained by an easy route

    Energy Technology Data Exchange (ETDEWEB)

    Perrella, R.V.; Schiavon, M.A. [Grupo de Pesquisa em Química de Materiais – (GPQM), Departamento de Ciências Naturais, Universidade Federal de São João del Rei (UFSJ), Campus Dom Bosco, Praça Dom Helvécio, 74, 36301-160 São João del Rei, MG (Brazil); Pecoraro, E.; Ribeiro, S.J.L. [UNESP, Institute of Chemistry, P.O. Box 355, 14800-970 Araraquara, SP (Brazil); Ferrari, J.L., E-mail: ferrari@ufsj.edu.br [Grupo de Pesquisa em Química de Materiais – (GPQM), Departamento de Ciências Naturais, Universidade Federal de São João del Rei (UFSJ), Campus Dom Bosco, Praça Dom Helvécio, 74, 36301-160 São João del Rei, MG (Brazil)

    2016-10-15

    This work reports on photoluminescence properties of Er{sup 3+}/Yb{sup 3+} co-doped CaYAlO{sub 4} in powder form, synthesized by an easy route using citric acid as ligand to form complex precursor. The 1.2 mol% of Yb{sup 3+} was fixed, while the amount of Er{sup 3+} changed in 0.5, 1.5 and 3 mol% in order to evaluate the photoluminescence properties as a function of the Er{sup 3+} concentration. The structural and thermal properties of the viscous solutions and powder materials obtained after the heat-treatment at 1000, 1100 and 1200 °C for 4 h were evaluated by XRD, FTIR and TG/DTA analysis. The results showed the formation of pure CaYAlO{sub 4} tetragonal crystalline phase after heat-treatment at 1100 °C and 1200 °C. Intense emission in the visible region under excitation at 980 nm was attributed to upconversion process, from Er{sup 3+} intra-configurational f–f transitions. The emissions were assigned to the transitions {sup 2}H{sub 11/2}→{sup 4}I{sub 15/2} and {sup 4}S{sub 3/2}→{sup 4}I{sub 15/2} (green region), and {sup 4}F{sub 9/2}→{sup 4}I{sub 15/2} (red region) energy levels. The ratio between emission band integrated areas assigned to the red and green emissions increased as a function of Er{sup 3+} concentration. Under excitation at 980 nm with 100 mW of power pump, the materials also showed intense and broadening emission with maximum at 1520 nm with FWHM of 84.74 nm for the sample CaYAlO{sub 4}:1.5% Er{sup 3+}/1.2% Yb{sup 3+} heat-treated at 1000 °C for 4 h. The photoluminescence properties showed that these materials are promising for use in C-telecom band as optical amplifier biological marker or/and solid-state laser devices under excitation at 980 nm.

  3. Dynamical screening effects in correlated electron materials-a progress report on combined many-body perturbation and dynamical mean field theory: 'GW + DMFT'.

    Science.gov (United States)

    Biermann, Silke

    2014-04-30

    We give a summary of recent progress in the field of electronic structure calculations for materials with strong electronic Coulomb correlations. The discussion focuses on developments beyond the by now well established combination of density functional and dynamical mean field theory dubbed 'LDA + DMFT'. It is organized around the description of dynamical screening effects in the solid. Indeed, screening in the solid gives rise to dynamical local Coulomb interactions U(ω) (Aryasetiawan et al 2004 Phys. Rev. B 70 195104), and this frequency dependence leads to effects that cannot be neglected in a truly first principles description. We review the recently introduced extension of LDA + DMFT to dynamical local Coulomb interactions 'LDA + U(ω) + DMFT' (Casula et al 2012 Phys. Rev. B 85 035115, Werner et al 2012 Nature Phys. 1745-2481). A reliable description of dynamical screening effects is also a central ingredient of the 'GW + DMFT' scheme (Biermann et al 2003 Phys. Rev. Lett. 90 086402), a combination of many-body perturbation theory in Hedin's GW approximation and dynamical mean field theory. Recently, the first GW + DMFT calculations including dynamical screening effects for real materials have been achieved, with applications to SrV O3 (Tomczak et al 2012 Europhys. Lett. 100 67001, Tomczak et al Phys. Rev. B submitted (available electronically as arXiv:1312.7546)) and adatom systems on surfaces (Hansmann et al 2013 Phys. Rev. Lett. 110 166401). We review these and comment on further perspectives in the field. This review is an attempt to put elements of the original works into the broad perspective of the development of truly first principles techniques for correlated electron materials.

  4. A PHOTONIC BAND GAP FIBRE

    DEFF Research Database (Denmark)

    1999-01-01

    An optical fibre having a periodicidal cladding structure provididing a photonic band gap structure with superior qualities. The periodical structure being one wherein high index areas are defined and wherein these are separated using a number of methods. One such method is the introduction...... of additional low index elements, another method is providing elongated elements deformed in relation to a circular cross section. Also described is a cladding structure comprising elongated elements of a material having an index of refraction higher than that of the material adjacent thereto. Using...

  5. [Multifunctional nanocomposite materials]. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    1993-04-01

    These novel nanocomposites are microporous nanometal intercalated clays which have been prepared by a polyol process at 200C and a novel microwave-hydrothermal process using ethylene glycol. These novel nanocomposites have been found to be useful in the conversion of coal to asphaltenes. A crystalline tin (IV) arsenate hydroxide hydrate has been made and its lithium selective ion exchange properties have been measured. This exchanger has shown high lithium selectivity. Selective exchange of divalent transition metal ions in cryptomelane-type manganic acid with tunnel structure have also been studied. Several pillared clays have also been synthesized and their Mg{sup 2+}, Li{sup +} and UO{sub 2}{sup 2+} selectivity has been measured. The pillared clays appear to show some Li selectivity.

  6. The laparoscopic banded gastric bypass – operation technique

    Directory of Open Access Journals (Sweden)

    Simon Küsters

    2010-03-01

    Full Text Available The banded Roux-en-Y gastric bypass can be used as a primary or revisionary bariatric procedure. This article describesthe operation technique including materials, size and placement of the banding and gives an overview con cerningevolution and indications of the operation. A video of a primary banded Roux-en-Y gastric bypass is presented.

  7. Wide Band to ''Double Band'' upgrade

    International Nuclear Information System (INIS)

    Kasper, P.; Currier, R.; Garbincius, P.; Butler, J.

    1988-06-01

    The Wide Band beam currently uses electrons obtained from secondary photon conversions to produce the photon beam incident on the experimental targets. By transporting the positrons produced in these conversions as well as the electrons it is possible to almost double the number of photons delivered to the experiments per primary beam proton. 11 figs

  8. Tulane/Xavier University Hazardous Materials in Aquatic Environments of the Mississippi River Basin. Quarterly progress report, January 1, 1995--March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    This progress report covers activities for the period January 1 - March 31, 1995 on project concerning `Hazardous Materials in Aquatic Environments of the Mississippi River Basin.` The following activities are each summarized by bullets denoting significant experiments/findings: biotic and abiotic studies on the biological fate, transport and ecotoxicity of toxic and hazardous waste in the Mississippi River Basin; assessment of mechanisms of metal-induced reproductive toxicity in quatic species as a biomarker of exposure; hazardous wastes in aquatic environments: biological uptake and metabolism studies; ecological sentinels of aquatic contamination in the lower Mississippi River system; bioremediation of selected contaminants in aquatic environments of the Mississippi River Basin; a sensitive rapid on-sit immunoassay for heavy metal contamination; pore-level flow, transport, agglomeration and reaction kinetics of microorganism; biomarkers of exposure and ecotoxicity in the Mississippi River Basin; natural and active chemical remediation of toxic metals, organics and radionuclides in the aquatic environment; expert geographical information systems for assessing hazardous wastes in aquatic environments; enhancement of environmental education; and a number of just initiated projects including fate and transport of contaminants in aquatic environments; photocatalytic remediation; radionuclide fate and modeling from Chernobyl.

  9. Tulane/Xavier University Hazardous Materials in Aquatic Environments of the Mississippi River Basin. Quarterly progress report, January 1, 1995--March 31, 1995

    International Nuclear Information System (INIS)

    1995-01-01

    This progress report covers activities for the period January 1 - March 31, 1995 on project concerning 'Hazardous Materials in Aquatic Environments of the Mississippi River Basin.' The following activities are each summarized by bullets denoting significant experiments/findings: biotic and abiotic studies on the biological fate, transport and ecotoxicity of toxic and hazardous waste in the Mississippi River Basin; assessment of mechanisms of metal-induced reproductive toxicity in quatic species as a biomarker of exposure; hazardous wastes in aquatic environments: biological uptake and metabolism studies; ecological sentinels of aquatic contamination in the lower Mississippi River system; bioremediation of selected contaminants in aquatic environments of the Mississippi River Basin; a sensitive rapid on-sit immunoassay for heavy metal contamination; pore-level flow, transport, agglomeration and reaction kinetics of microorganism; biomarkers of exposure and ecotoxicity in the Mississippi River Basin; natural and active chemical remediation of toxic metals, organics and radionuclides in the aquatic environment; expert geographical information systems for assessing hazardous wastes in aquatic environments; enhancement of environmental education; and a number of just initiated projects including fate and transport of contaminants in aquatic environments; photocatalytic remediation; radionuclide fate and modeling from Chernobyl

  10. Phononic band gap structures as optimal designs

    DEFF Research Database (Denmark)

    Jensen, Jakob Søndergaard; Sigmund, Ole

    2003-01-01

    In this paper we use topology optimization to design phononic band gap structures. We consider 2D structures subjected to periodic loading and obtain the distribution of two materials with high contrast in material properties that gives the minimal vibrational response of the structure. Both in...

  11. Band - Weg interactie

    NARCIS (Netherlands)

    de Boer, Andries; ter Huerne, Henderikus L.; Noordermeer, Jacobus W.M.; Schipper, Dirk J.; prof.dr.ir. Molenaar, A.A.A.

    2008-01-01

    De huidige infrastructuur van wegen waarover men zich snel en comfortabel kan verplaatsen is niet meer weg te denken uit onze maatschappij. Twee “componenten” die hierbij een belangrijke rol spelen zijn het wegdek en de band. Het contact tussen band en wegdek is mede bepalend voor de veiligheid. De

  12. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric

  13. Effect of segregation bands on corrosion of steel plate for ship hull

    Directory of Open Access Journals (Sweden)

    M. Mazur

    2010-07-01

    Full Text Available Despite significant progress in the manufacturing of sheet metal ships carried both by optimizing the chemical compositions of steel mills as well as rolling and heat treatment, it still fails to remove the effects of persistent segregation. As a result we observed anisotropy of mechanical properties of the material which essentially complicates the process of construction for shipbuilding industry. Anisotropy of mechanical properties occurring in sheet metal hull is even more dangerous, that during their work, they are exposed to continuous exposure variable charges arising from sea surface waves. Another factor weakening the resistance to cracking metal ship is sea-water, which in the surface layer is highly aerated and very aggressive corrosion. The purpose of this study is to clarify the role of the segregation bands in the process of corrosion of low alloy steels used for ship hull. It was estimate a rate of corrosion in aerated sea water areas of the metal with or without segregation bands. After corrosion tests were made observations of specimens surfaces. Inside the segregation bands were found phosphorus. The contents of it were exceeded the average this element content in the steel. At the same time areas of the sheet metal with segregation bands were slowly corroded than areas without bands, although the changes of corrosion rate was similar in nature.Corrosion activity of rich in phosphorus segregation band is similar to phosphate corrosion inhibitors. These are effective in the presenceof chloride in seawater to form a protective layer that protects against corrosion segregation band. Under the observation on scanningelectron microscope there was no change in the appearance of surface samples after corrosion tests. A future direction of research will be estimate the stress corrosion in the same species – with and without segregation bands.

  14. The Volpe Center GPS Adjacent Band Compatibility Program Plan : GPS Adjacent Band Compatibility Workshop, Volpe Center, Cambridge MA

    Science.gov (United States)

    2014-09-18

    Approach to DOT GPS Adjacent Band Compatibility Assessment. Identify forums and provide public outreach to make sure the progress and work are as open and transparent as possible. Develop an implementation plan that incorporates aspects from the DOT ...

  15. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory...... are computed using a first-principles theory based upon the generalized-gradient approximation to the density-functional theory. These parameters and Hamiltonian will be useful for modeling physical properties of phosphorene....

  16. Photonic Band Gap Accelerator Demonstration at Ku-Band.

    CERN Document Server

    Smirnova, Evgenya I; Edwards, Randall L; Kesar, Amit S; Mastovsky, Ivan; Shapiro, Michael A; Temkin, Richard J

    2005-01-01

    We report progress on the design and cold test of a metal Ku-band PBG accelerator structure. The 17.140 GHz 6-cell PBG accelerator structure with reduced long-range wakefields was designed for the experiment. The copper structure was electroformed and cold-tested. Tuning was performed through chemical etching of the rods. Final cold test measurements were found to be in very good agreement with the design. The structure will be installed on the beam line at the accelerator laboratory at Massachusetts Institute of Technology and will be powered with 3 MW of peak power from the Haimson 17.14 GHz klystron. Results of the design, fabrication, cold test and hot test on the Haimson accelerator will be presented.

  17. Visualizing shear bands in 3-D using axisymmetric sample: An experimental study

    Directory of Open Access Journals (Sweden)

    W. Khraisat

    2017-07-01

    Full Text Available In this study a qualitative description of the occurrence of shear bands produced by a sudden impact on an axisymmetric specimen made of medium carbon steel 0.45% C is given. A simple experiment was developed aimed at producing a pinch shear stress in the front side of the test sample in order to visualize shear bands in 3-D. Curve fitting using MATLAB was employed based on the points taken from the images of the front section of the test sample. The predictions of the curve fitting suggests a hyperbolic section leading to the conclusion that within the sample there is a double cone region of material where the shear band region is located on its outer surface. The formation of the shear band is explained by the fact that the interaction of the stress wave front with the free surface of the test sample produces reflection waves that attenuate the incoming stress wave inwards leading to a stress gradient in the plane of the front side of the specimen that causes shear localization. Also, the progressively increasing cross sectional area of the test sample causes the expansion of the wave front, which also results in a stress gradient in the normal direction of the front side of the specimen. So the formation of shear bands depends not only on the impact momentum and strain rates but also on the sample’s geometry.

  18. Laparoscopic gastric banding

    Science.gov (United States)

    ... eat by making you feel full after eating small amounts of food. After surgery, your doctor can adjust the band ... You will feel full after eating just a small amount of food. The food in the small upper pouch will ...

  19. HYBASE - HYperspectral BAnd SElection tool

    NARCIS (Netherlands)

    Schwering, P.B.W.; Bekman, H.H.P.T.; Seijen, H.H. van

    2008-01-01

    Band selection is essential in the design of multispectral sensor systems. This paper describes the TNO hyperspectral band selection tool HYBASE. It calculates the optimum band positions given the number of bands and the width of the spectral bands. HYBASE is used to calculate the minimum number of

  20. Hurricane Spiral Bands.

    Science.gov (United States)

    Guinn, Thomas A.; Schubert, Wayne H.

    1993-10-01

    The spiral bands that occur in tropical cyclones can be conveniently divided into two classes-outer bands and inner bands. Evidence is presented here that the outer bands form as the result of nonlinear effects during the breakdown of the intertropical convergence zone (ITCZ) through barotropic instability. In this process a zonal strip of high potential vorticity (the ITCZ shear zone or monsoon trough) begins to distort in a varicose fashion, with the potential vorticity (PV) becoming pooled in local regions that are connected by filaments of high PV. As the pooled regions become more axisymmetric, the filaments become thinner and begin to wrap around the PV centers.It is argued that inner bands form in a different manner. As a tropical cyclone intensifies due to latent heat release, the PV field becomes nearly circular with the highest values of PV in the cyclone center. The radial gradient of PV provides a state on which PV waves (the generalization of Rossby waves) can propagate. The nonlinear breaking of PV waves then leads to an irreversible distortion of the PV contours and a downgradient flux of PV. The continuation of this proem tends to erode the high PV core of the tropical cyclone, to produce a surrounding surf zone, and hence to spread the PV horizontally. In a similar fashion, inner bands can also form by the merger of a vortex with a patch of relatively high PV air. As the merger proem occurs the patch of PV is quickly elongated and wrapped around the vortex. The resulting vortex is generally larger in horizontal extent and exhibits a spiral band of PV.When the formation of outer and inner bands is interpreted in the context of a normal-mode spectral model, they emerge as slow manifold phenomena; that is, they have both rotational and (balanced or slaved) gravitational mode aspects. In this sense, regarding them as simply gravity waves leads to an incomplete dynamical picture.

  1. Thermoelectric band engineering: The role of carrier scattering

    Science.gov (United States)

    Witkoske, Evan; Wang, Xufeng; Lundstrom, Mark; Askarpour, Vahid; Maassen, Jesse

    2017-11-01

    Complex electronic band structures, with multiple valleys or bands at the same or similar energies, can be beneficial for thermoelectric performance, but the advantages can be offset by inter-valley and inter-band scattering. In this paper, we demonstrate how first-principles band structures coupled with recently developed techniques for rigorous simulation of electron-phonon scattering provide the capabilities to realistically assess the benefits and trade-offs associated with these materials. We illustrate the approach using n-type silicon as a model material and show that intervalley scattering is strong. This example shows that the convergence of valleys and bands can improve thermoelectric performance, but the magnitude of the improvement depends sensitively on the relative strengths of intra- and inter-valley electron scattering. Because anisotropy of the band structure also plays an important role, a measure of the benefit of band anisotropy in the presence of strong intervalley scattering is presented.

  2. Bi-directional evolutionary optimization for photonic band gap structures

    Science.gov (United States)

    Meng, Fei; Huang, Xiaodong; Jia, Baohua

    2015-12-01

    Toward an efficient and easy-implement optimization for photonic band gap structures, this paper extends the bi-directional evolutionary structural optimization (BESO) method for maximizing photonic band gaps. Photonic crystals are assumed to be periodically composed of two dielectric materials with the different permittivity. Based on the finite element analysis and sensitivity analysis, BESO starts from a simple initial design without any band gap and gradually re-distributes dielectric materials within the unit cell so that the resulting photonic crystal possesses a maximum band gap between two specified adjacent bands. Numerical examples demonstrated the proposed optimization algorithm can successfully obtain the band gaps from the first to the tenth band for both transverse magnetic and electric polarizations. Some optimized photonic crystals exhibit novel patterns markedly different from traditional designs of photonic crystals.

  3. Bi-directional evolutionary optimization for photonic band gap structures

    International Nuclear Information System (INIS)

    Meng, Fei; Huang, Xiaodong; Jia, Baohua

    2015-01-01

    Toward an efficient and easy-implement optimization for photonic band gap structures, this paper extends the bi-directional evolutionary structural optimization (BESO) method for maximizing photonic band gaps. Photonic crystals are assumed to be periodically composed of two dielectric materials with the different permittivity. Based on the finite element analysis and sensitivity analysis, BESO starts from a simple initial design without any band gap and gradually re-distributes dielectric materials within the unit cell so that the resulting photonic crystal possesses a maximum band gap between two specified adjacent bands. Numerical examples demonstrated the proposed optimization algorithm can successfully obtain the band gaps from the first to the tenth band for both transverse magnetic and electric polarizations. Some optimized photonic crystals exhibit novel patterns markedly different from traditional designs of photonic crystals.

  4. Real-time recursive hyperspectral sample and band processing algorithm architecture and implementation

    CERN Document Server

    Chang, Chein-I

    2017-01-01

    This book explores recursive architectures in designing progressive hyperspectral imaging algorithms. In particular, it makes progressive imaging algorithms recursive by introducing the concept of Kalman filtering in algorithm design so that hyperspectral imagery can be processed not only progressively sample by sample or band by band but also recursively via recursive equations. This book can be considered a companion book of author’s books, Real-Time Progressive Hyperspectral Image Processing, published by Springer in 2016. Explores recursive structures in algorithm architecture Implements algorithmic recursive architecture in conjunction with progressive sample and band processing Derives Recursive Hyperspectral Sample Processing (RHSP) techniques according to Band-Interleaved Sample/Pixel (BIS/BIP) acquisition format Develops Recursive Hyperspectral Band Processing (RHBP) techniques according to Band SeQuential (BSQ) acquisition format for hyperspectral data.

  5. Review of wide band-gap semiconductors technology

    Directory of Open Access Journals (Sweden)

    Jin Haiwei

    2016-01-01

    Full Text Available Silicon carbide (SiC and gallium nitride (GaN are typical representative of the wide band-gap semiconductor material, which is also known as third-generation semiconductor materials. Compared with the conventional semiconductor silicon (Si or gallium arsenide (GaAs, wide band-gap semiconductor has the wide band gap, high saturated drift velocity, high critical breakdown field and other advantages; it is a highly desirable semiconductor material applied under the case of high-power, high-temperature, high-frequency, anti-radiation environment. These advantages of wide band-gap devices make them a hot spot of semiconductor technology research in various countries. This article describes the research agenda of United States and European in this area, focusing on the recent developments of the wide band-gap technology in the US and Europe, summed up the facing challenge of the wide band-gap technology.

  6. Restrictive techniques: gastric banding

    Directory of Open Access Journals (Sweden)

    Katia Cristina da Cunha

    2006-03-01

    Full Text Available Surgery for the treatment of severe obesity has a definite role onthe therapeutic armamentarium all over the world. Initiated 40years ago, bariatric surgery has already a long way thanks tohundred of surgeons, who had constantly searched for the besttechnique for the adequate control of severe obesity. Among theimportant breakthroughs in obesity surgery there is theadjustable gastric band. It is a sylastic band, inflatable andadjustable, which is placed on the top of the stomach in order tocreate a 15-20 cc pouch, with an outlet of 1.3cm. The adjustablegastric band has also a subcutaneous reservoir through whichadjustments can be made, according to the patient evolution.The main feature of the adjustable gastric band is the fact thatis minimal invasive, reversible, adjustable and placedlaparoscopically. Then greatly diminishing the surgical traumato the severe obese patient. Belachew and Favretti’s techniqueof laparoscopic application of the adjustable gastric band isdescribed and the evolution of the technique during this years,as we has been practiced since 1998. The perioperative care ofthe patient is also described, as well as the follow-up and shortand long term controls.

  7. Recent Progress in the Design of Advanced Cathode Materials and Battery Models for High-Performance Lithium-X (X = O2 , S, Se, Te, I2 , Br2 ) Batteries.

    Science.gov (United States)

    Xu, Jiantie; Ma, Jianmin; Fan, Qinghua; Guo, Shaojun; Dou, Shixue

    2017-07-01

    Recent advances and achievements in emerging Li-X (X = O 2 , S, Se, Te, I 2 , Br 2 ) batteries with promising cathode materials open up new opportunities for the development of high-performance lithium-ion battery alternatives. In this review, we focus on an overview of recent important progress in the design of advanced cathode materials and battery models for developing high-performance Li-X (X = O 2 , S, Se, Te, I 2 , Br 2 ) batteries. We start with a brief introduction to explain why Li-X batteries are important for future renewable energy devices. Then, we summarize the existing drawbacks, major progress and emerging challenges in the development of cathode materials for Li-O 2 (S) batteries. In terms of the emerging Li-X (Se, Te, I 2 , Br 2 ) batteries, we systematically summarize their advantages/disadvantages and recent progress. Specifically, we review the electrochemical performance of Li-Se (Te) batteries using carbonate-/ether-based electrolytes, made with different electrode fabrication techniques, and of Li-I 2 (Br 2 ) batteries with various cell designs (e.g., dual electrolyte, all-organic electrolyte, with/without cathode-flow mode, and fuel cell/solar cell integration). Finally, the perspective on and challenges for the development of cathode materials for the promising Li-X (X = O 2 , S, Se, Te, I 2 , Br 2 ) batteries is presented. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. 1985. Annual progress report

    International Nuclear Information System (INIS)

    1986-01-01

    This annual progress report of the CEA Protection and Nuclear Safety Institut outlines a description of the progress made in each sections of the Institut Research activities of the different departments include: reactor safety analysis, fuel cycle facilities analysis; and associated safety research programs (criticality, sites, transport ...), radioecology and environmental radioprotection techniques; data acquisition on radioactive waste storage sites; radiation effects on man, studies on radioprotection techniques; nuclear material security including security of facilities, security of nuclear material transport, and monitoring of nuclear material management; nuclear facility decommissioning; and finally the public information [fr

  9. Staggered broad-band reflecting multilayers.

    Science.gov (United States)

    Heavens, O S; Liddell, H M

    1966-03-01

    Considerable broadening of the reflectance band of a multilayer stack may be obtained by staggering the layer thicknesses in such a way that they form either an arithmetic or geometric progression. Results are shown for asymmetric and symmetric filters of 15, 25, and 35 layers. The presence of the narrowband transmission peaks exhibited by the symmetric filters is explained, and the advantages of the use of this type of filter as an interference filter is discussed.

  10. Ultra wide band antennas

    CERN Document Server

    Begaud, Xavier

    2013-01-01

    Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recog

  11. University of Illinois at Urbana-Champaign, Materials Research Laboratory progress report for FY 1993 and research proposal for FY 1994

    Energy Technology Data Exchange (ETDEWEB)

    Birnbaum, H.K.

    1993-03-01

    The materials research laboratory program is about 30% of total Materials Science and Engineering effort on the Univ. of Illinois campus. Coordinated efforts are being carried out in areas of structural ceramics, grain boundaries, field responsive polymeric and organic materials, molecular structure of solid-liquid interfaces and its relation to corrosion, and x-ray scattering science.

  12. Band Edge Dynamics and Multiexciton Generation in Narrow Band Gap HgTe Nanocrystals.

    Science.gov (United States)

    Livache, Clément; Goubet, Nicolas; Martinez, Bertille; Jagtap, Amardeep; Qu, Junling; Ithurria, Sandrine; Silly, Mathieu G; Dubertret, Benoit; Lhuillier, Emmanuel

    2018-04-02

    Mercury chalcogenide nanocrystals and especially HgTe appear as an interesting platform for the design of low cost mid-infrared (mid-IR) detectors. Nevertheless, their electronic structure and transport properties remain poorly understood, and some critical aspects such as the carrier relaxation dynamics at the band edge have been pushed under the rug. Some of the previous reports on dynamics are setup-limited, and all of them have been obtained using photon energy far above the band edge. These observations raise two main questions: (i) what are the carrier dynamics at the band edge and (ii) should we expect some additional effect (multiexciton generation (MEG)) as such narrow band gap materials are excited far above the band edge? To answer these questions, we developed a high-bandwidth setup that allows us to understand and compare the carrier dynamics resonantly pumped at the band edge in the mid-IR and far above the band edge. We demonstrate that fast (>50 MHz) photoresponse can be obtained even in the mid-IR and that MEG is occurring in HgTe nanocrystal arrays with a threshold around 3 times the band edge energy. Furthermore, the photoresponse can be effectively tuned in magnitude and sign using a phototransistor configuration.

  13. Band-notched spiral antenna

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Jae; Chang, John

    2018-03-13

    A band-notched spiral antenna having one or more spiral arms extending from a radially inner end to a radially outer end for transmitting or receiving electromagnetic radiation over a frequency range, and one or more resonance structures positioned adjacent one or more segments of the spiral arm associated with a notch frequency band or bands of the frequency range so as to resonate and suppress the transmission or reception of electromagnetic radiation over said notch frequency band or bands.

  14. Flat Chern Band in a Two-Dimensional Organometallic Framework

    Science.gov (United States)

    Liu, Zheng; Wang, Zheng-Fei; Mei, Jia-Wei; Wu, Yong-Shi; Liu, Feng

    2013-03-01

    By combining exotic band dispersion with nontrivial band topology, an interesting type of band structure, namely, the flat Chern band, has recently been proposed to spawn high-temperature fractional quantum Hall states. Despite the proposal of several theoretical lattice models, however, it remains doubtful whether such a “romance of flatland” could exist in a real material. Here, we present a first-principles design of a two-dimensional indium-phenylene organometallic framework that realizes a nearly flat Chern band right around the Fermi level by combining lattice geometry, spin-orbit coupling, and ferromagnetism. An effective four-band model is constructed to reproduce the first-principles results. Our design, in addition, provides a general strategy to synthesize topologically nontrivial materials by virtue of organic chemistry and nanotechnology.

  15. Formation of Degenerate Band Gaps in Layered Systems

    Directory of Open Access Journals (Sweden)

    Alexey P. Vinogradov

    2012-06-01

    Full Text Available In the review, peculiarities of spectra of one-dimensional photonic crystals made of anisotropic and/or magnetooptic materials are considered. The attention is focused on band gaps of a special type—the so called degenerate band gaps which are degenerate with respect to polarization. Mechanisms of formation and properties of these band gaps are analyzed. Peculiarities of spectra of photonic crystals that arise due to the linkage between band gaps are discussed. Particularly, it is shown that formation of a frozen mode is caused by linkage between Brillouin and degenerate band gaps. Also, existence of the optical Borrmann effect at the boundaries of degenerate band gaps and optical Tamm states at the frequencies of degenerate band gaps are analyzed.

  16. Asymmetric Semiconductor Nanorod/Oxide Nanoparticle Hybrid Materials: Model Nanomaterials for Light-Activated Formation of Fuels from Sunlight. Formal Progress Report -- Award DE-FG02-05ER15753

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Neal R. [Univ. of Arizona, Tucson, AZ (United States)

    2017-06-22

    Executive Summary on Project Accomplishments: We focused our efforts for this project on the synthesis and characterization of semiconductor nanomaterials composed of semiconductor nanorods (NRs - e.g., CdSe, CdSe@CdS, CdS) with metal (Au, Pt, Co) or metal oxide (CoxOy) nanoparticle (NP) “tips.” These systems are attractive model systems where control of spatial, energetic and compositional features of both NRs and NP tips potentially enhances the efficiency of photogeneration and directional transport of charges, and photoelectrochemical conversion of sunlight to fuels. Synthetic methods to control material dimensions (20-200 nm in length), topology (one vs. two NP tips) and NR/NP tip compositions have been developed in the current project period (Pyun). We also achieved, for the first time in heterostructured nanorod materials, estimates of both valence band energies (EVB) and conduction band energies (ECB), using unique combinations of in vacuuo ultraviolet photoelectron spectroscopy (UPS, Armstrong), and waveguide spectroelectrochemistry (Saavedra), respectively. The spectroelectrochemical measurements in particular provide a unique path to estimation of ECB, and the distribution in ECB brought about by modification of NR composition. The combination of both approaches promises to be universally applicable to the characterization of energetics in nanomaterials of interest both for photovoltaic and sunlight-to-fuel photoelectrochemical assemblies.

  17. Enhancing Solar Cell Efficiency Using Photon Upconversion Materials

    Directory of Open Access Journals (Sweden)

    Yunfei Shang

    2015-10-01

    Full Text Available Photovoltaic cells are able to convert sunlight into electricity, providing enough of the most abundant and cleanest energy to cover our energy needs. However, the efficiency of current photovoltaics is significantly impeded by the transmission loss of sub-band-gap photons. Photon upconversion is a promising route to circumvent this problem by converting these transmitted sub-band-gap photons into above-band-gap light, where solar cells typically have high quantum efficiency. Here, we summarize recent progress on varying types of efficient upconversion materials as well as their outstanding uses in a series of solar cells, including silicon solar cells (crystalline and amorphous, gallium arsenide (GaAs solar cells, dye-sensitized solar cells, and other types of solar cells. The challenge and prospect of upconversion materials for photovoltaic applications are also discussed

  18. Progress in the analysis of non-axisymmetric wave propagation in a homogeneous solid circular cylinder of a piezoelectric transversely isotropic material

    CSIR Research Space (South Africa)

    Every, AG

    2010-01-01

    Full Text Available at www.sciencedirect.com Physics Procedia 00 (2009) 000?000 www.elsevier.com/locate/procedia International Congress on Ultrasonics, Universidad de Santiago de Chile, January 2009 Progress in the analysis of non-axisymmetric wave propagation in a...

  19. Development of a Control Banding Tool for Nanomaterials

    OpenAIRE

    Riediker, M.; Ostiguy, C.; Triolet, J.; Troisfontaine, P.; Vernez, D.; Bourdel, G.; Thieriet, N.; Cadène, A.

    2012-01-01

    Control banding (CB) can be a useful tool for managing the potential risks of nanomaterials. The here proposed CB, which should be part of an overall risk control strategy, groups materials by hazard and emission potential. The resulting decision matrix proposes control bands adapted to the risk potential levels and helps define an action plan. If this plan is not practical and financially feasible, a full risk assessment is launched. The hazard banding combines key concepts of nanomaterial t...

  20. Chemistry and Materials Science Weapons-Supporting Research and Laboratory-Directed Research and Development. Second half progress report, FY 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    Thrust areas of the weapons-supporting research are surface research, uranium research, physics and processing of metals, energetic materials. Group study areas included strength of Al and Al-Mg/alumina bonds, advanced synchrotron radiation study of materials, and theory, modeling, and computation. Individual projects were life prediction for composites and thermoelectric materials with exceptional figures of merit. The laboratory-directed R and D include director`s initiatives (aerogel-based electronic devices, molecular levels of energetic materials), individual projects, and transactinium institute studies. An author index is provided.

  1. Fossil Energy Advanced Research and Technology Development (AR&TD) Materials Program semiannual progress report for the period ending September 30, 1991. Fossil Energy Program

    Energy Technology Data Exchange (ETDEWEB)

    Judkins, R.R.; Cole, N.C. [comps.

    1992-04-01

    The objective of the Fossil Energy Advanced Research and Technology Development Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The Program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. Research is outlined in four areas: Ceramics, New Alloys, Corrosion and Erosion Research, and Technology Development and Transfer. (VC)

  2. Fossil Energy Advanced Research and Technology Development (AR TD) Materials Program semiannual progress report for the period ending September 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Judkins, R.R.; Cole, N.C. (comps.)

    1992-04-01

    The objective of the Fossil Energy Advanced Research and Technology Development Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The Program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. Research is outlined in four areas: Ceramics, New Alloys, Corrosion and Erosion Research, and Technology Development and Transfer. (VC)

  3. Designing broad phononic band gaps for in-plane modes

    Science.gov (United States)

    Li, Yang Fan; Meng, Fei; Li, Shuo; Jia, Baohua; Zhou, Shiwei; Huang, Xiaodong

    2018-03-01

    Phononic crystals are known as artificial materials that can manipulate the propagation of elastic waves, and one essential feature of phononic crystals is the existence of forbidden frequency range of traveling waves called band gaps. In this paper, we have proposed an easy way to design phononic crystals with large in-plane band gaps. We demonstrated that the gap between two arbitrarily appointed bands of in-plane mode can be formed by employing a certain number of solid or hollow circular rods embedded in a matrix material. Topology optimization has been applied to find the best material distributions within the primitive unit cell with maximal band gap width. Our results reveal that the centroids of optimized rods coincide with the point positions generated by Lloyd's algorithm, which deepens our understandings on the formation mechanism of phononic in-plane band gaps.

  4. Development of New Low-Cost, High-Performance, PV Module Encapsulant/Packaging Materials: Final Technical Progress Report, 22 October 2002 - 15 November 2007

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, R.

    2008-04-01

    Report on objectives to work with U.S.-based PV module manufacturers (c-Si, a-Si, CIS, other thin films) to develop/qualify new low-cost, high-performance PV module encapsulant/packaging materials, and processes using the packaging materials.

  5. TASCC Division progress report

    International Nuclear Information System (INIS)

    Hardy, J.C.

    1992-10-01

    The TASCC (Tandem Accelerator-Superconducting Cyclotron) facility is devoted to developing and providing beams for an experimental program of basic nuclear research. Beam was on target for 2901 hours during the period of interest. The cyclotron provided beam for 524 hours, and tandem beams were used for a total of 3940 hours. The most exciting experimental result was the first evidence of a rotational band with the characteristics of hyperdeformation: a ridge-valley structure in 152 Dy. This progress report details experimental results and instrumentation and facility development over the period. (L.L.) (refs., tabs., figs.)

  6. Band Gap Engineering of Titania Systems Purposed for Photocatalytic Activity

    Science.gov (United States)

    Thurston, Cameron

    Ab initio computer aided design drastically increases candidate population for highly specified material discovery and selection. These simulations, carried out through a first-principles computational approach, accurately extrapolate material properties and behavior. Titanium Dioxide (TiO2 ) is one such material that stands to gain a great deal from the use of these simulations. In its anatase form, titania (TiO2 ) has been found to exhibit a band gap nearing 3.2 eV. If titania is to become a viable alternative to other contemporary photoactive materials exhibiting band gaps better suited for the solar spectrum, then the band gap must be subsequently reduced. To lower the energy needed for electronic excitation, both transition metals and non-metals have been extensively researched and are currently viable candidates for the continued reduction of titania's band gap. The introduction of multicomponent atomic doping introduces new energy bands which tend to both reduce the band gap and recombination loss. Ta-N, Nb-N, V-N, Cr-N, Mo-N, and W-N substitutions were studied in titania and subsequent energy and band gap calculations show a favorable band gap reduction in the case of passivated systems.

  7. A charge distribution analysis instrument for catalysis and material science applications. Third quarterly technical progress report, April 1, 1994--June 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Freund, F.

    1994-08-05

    Key component in the CDA instrument is the differential capacitive force sensor. The CDA instrument has four basic components: OEM analytical balance, flexure point and capacitor plates, gas confinement tower and high-voltage bias electrodes, and the furnace. Phyton is in position to purchase an OEM analytical balance; negotations are underway for obtaining the feedback control circuitry for the differential capacitive force sensor. Progress with the differential capacitive force sensor is reviewed.

  8. Progress Report

    DEFF Research Database (Denmark)

    Duer, Karsten

    1999-01-01

    Progress report describing the work carried out by the Danish participant in the ALTSET project in the period January 1999 to July 1999.......Progress report describing the work carried out by the Danish participant in the ALTSET project in the period January 1999 to July 1999....

  9. A theoretical and numerical study of the flow of granular materials down an inclined plane. [Quarterly progress report, January--March 1995

    Energy Technology Data Exchange (ETDEWEB)

    Rajagopal, K.R.

    1995-09-01

    The mechanics of the flowing granular materials such as coal, agricultural products, fertilizers, dry chemicals, metal ores, etc. have received a great deal of attention as it has relevance to several important technological problems. Despite wide interest and more than five decades of experimental and theoretical investigations, most aspects of the behavior of flowing granular materials are still not well understood. So Experiments have to be devised which quantify and describe the non-linear behavior of the granular materials, and theories developed which can explain the experimentally observed facts. Here we carry out a systematic numerical study of the flow of granular materials down an inclined plane using the models that stem from both the continuum theory approach and the kinetic theory approach. We also look at the existence of solutions, multiplicity and stability of solutions to the governing equations.

  10. Homotopy Shear Band Solutions in Gradient Plasticity

    Science.gov (United States)

    Raees, Ammarah; Xu, Hang; Aifantis, Elias C.

    2017-05-01

    Analytical shear band type solutions for finite domains are derived within the framework of gradient plasticity theory by employing the homotopy analysis method (HAM). Such types of solutions were available in the literature only for infinite domains in the nonlinear material softening regime and steady-state conditions, as well as for finite domains in the material hardening regime. HAM allows for solutions to be obtained for both hardening and softening material models, as well as for unsteady conditions periodic solutions are also derived. The HAM results are verified with numerical simulations, which show excellent agreement. Moreover, an error analysis is provided which guarantees the convergence of our series solution.

  11. Electronic pairing mechanism due to band modification in a two-band model: Tc evaluation

    International Nuclear Information System (INIS)

    Mizia, J.; Gorski, G.; Traa, M.R.M.J.

    1997-01-01

    Following the electronic model developed by us previously (Mizia and Romanowski, Mizia) we estimate the superconducting transition temperature in a simple electronic two-band model for materials characterized by a broad superconducting band and a narrow level within the same energy range. A large electron deformation coupling constant and large electron correlation effects are assumed. It is shown that high-temperature superconductivity is entirely possible within a range of reasonable electronic parameters. This model does not assume any artificial interactions to obtain a negative pairing potential. Instead, the negative part of the electronic interaction potential comes from the modification of the electron dispersion relation with growing number of superconducting pairs. Such a modification is possible in soft electronic systems, i.e. in systems partial to band modification due to large internal stresses, strong electronic correlation effects and broad band narrow level charge transfer during the superconducting transition. (orig.)

  12. Transport in bilayer and trilayer graphene: band gap engineering and band structure tuning

    Science.gov (United States)

    Zhu, Jun

    2014-03-01

    Controlling the stacking order of atomically thin 2D materials offers a powerful tool to control their properties. Linearly dispersed bands become hyperbolic in Bernal (AB) stacked bilayer graphene (BLG). Both Bernal (ABA) and rhombohedral (ABC) stacking occur in trilayer graphene (TLG), producing distinct band structures and electronic properties. A symmetry-breaking electric field perpendicular to the sample plane can further modify the band structures of BLG and TLG. In this talk, I will describe our experimental effort in these directions using dual-gated devices. Using thin HfO2 film deposited by ALD as gate dielectric, we are able to apply large displacement fields D > 6 V/nm and observe the opening and saturation of the field-induced band gap Eg in bilayer and ABC-stacked trilayer graphene, where the conduction in the mid gap changes by more than six decades. Its field and temperature dependence highlights the crucial role played by Coulomb disorder in facilitating hopping conduction and suppressing the effect of Eg in the tens of meV regime. In contrast, mid-gap conduction decreases with increasing D much more rapidly in clean h-BN dual-gated devices. Our studies also show the evolution of the band structure in ABA-stacked TLG, in particular the splitting of the Dirac-like bands in large D field and the signatures of two-band transport at high carrier densities. Comparison to theory reveals the need for more sophisticated treatment of electronic screening beyond self-consistent Hartree calculations to accurately predict the band structures of trilayer graphene and graphenic materials in general.

  13. Endoscopic management of erosion after banded bariatric procedures.

    Science.gov (United States)

    Spann, Matthew D; Aher, Chetan V; English, Wayne J; Williams, D Brandon

    2017-11-01

    Prosthetic materials wrapped around a portion of the stomach have been used to provide gastric restriction in bariatric surgery for many years. Intraluminal erosion of adjustable and nonadjustable gastric bands typically occurs many years after placement and results in various symptoms. Endoscopic management of gastric band erosion has been described and allows for optimal patient outcomes. We will describe our methods and experience with endoscopic management of intraluminal gastric band erosions after bariatric procedures. University hospital in the United States. A retrospective review of our bariatric surgery database identified patients undergoing removal of gastric bands. A chart review was then undertaken to confirm erosion of prosthetic material into the gastrointestinal tract. Baseline characteristics, operative reports, and follow-up data were analyzed. Sixteen patients were identified with an eroded gastric band: 11 after banded gastric bypass, 3 after laparoscopic adjustable gastric band (LAGB), and 2 after vertical banded gastroplasty. All patients were successfully treated with endoscopic removal of the prosthetic materials using either endoscopic scissors or ligation of the banding material with off-label use of a mechanical lithotripter device. Complications included a postoperative gastrointestinal bleed requiring repeat endoscopy, 1 patient with asymptomatic pneumoperitoneum requiring observation, and 1 with seroma at the site of LAGB port removal. Endoscopic management of intraluminal prosthetic erosion after gastric banded bariatric procedures can be safe and effective and should be considered when treating this complication. Erosion of the prosthetic materials inside the gastric lumen allows for potential endoscopic removal without free intraabdominal perforation. Endoscopic devices designed for dividing eroded LAGBs may help standardize and increase utilization of this approach. Copyright © 2017 American Society for Bariatric Surgery

  14. Microstrip microwave band gap structures

    Indian Academy of Sciences (India)

    Microwave band gap structures exhibit certain stop band characteristics based on the periodicity, impedance contrast and effective refractive index contrast. These structures though formed in one-, two- and three-dimensional periodicity, are huge in size. In this paper, microstrip-based microwave band gap structures are ...

  15. An innovative band-to-band tunneling analytical model and implications in compact modeling of tunneling-based devices

    Science.gov (United States)

    De Michielis, L.; Daǧtekin, N.; Biswas, A.; Lattanzio, L.; Selmi, L.; Luisier, M.; Riel, H.; Ionescu, A. M.

    2013-09-01

    In this paper, an analytical band-to-band tunneling model is proposed, validated by means of drift-diffusion simulation and comparison with experimental data, implemented in Verilog-A, and finally proven with SPICE simulator through simulation of circuits featuring tunneling diodes. The p-n junction current calculation starts from a non-local Band-to-Band tunneling theory including the electron-phonon interaction and therefore it is particularly suited for indirect semiconductor materials such as silicon- or germanium-based interband tunneling devices.

  16. Investigation of test methods, material properties, and processes for solar cell encapsulants. Ninth quarterly progress report, May 12, 1978--August 12, 1978

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-10-01

    The technical activities were directed toward further assessment of protective outer cover materials, an examination of the outdoor weathering effects on various plastics, the development of an ethylene/vinyl acetate copolymer pottant, and a mechanical analysis of composite substrate materials. Permasorb-MA, a copolymerized ultraviolet absorber in an acrylic coating vehicle, was evaluated for its effectiveness by the protection it provided to unstabilized polypropylene. The weathering effects on eleven polymers exposed to twelve months of weathering in Phoenix, Florida, and under EMMAQUA were evaluated by determination of tensile strengths, elongations, optical transmission, etc. Development efforts were applied to ethylene/vinyl acetate ccopolymer (EVA) in order to test the viability of this compound as an experimental pottant. A mechanical engineering analysis of composite structural materials useful as substrates is included.

  17. Progress report 1979

    International Nuclear Information System (INIS)

    1980-12-01

    This progress report deals with technical and research work done at the AAEC Research Establishment in the twelve month period ending September 30, 1979. Work done in the following research divisions is reported: Applied Maths and Computing, Chemical Technology, Engineering Research, Environmental Science, Instrumentation and Control, Isotope, Materials and Physics

  18. Progressive Business

    DEFF Research Database (Denmark)

    Christiansen, Christian O.

    2016-01-01

    Guest Post to the Society for U.S. Intellectual History Blog. Brief introduction to the book Progressive Business: An Intellectual History of the Role of Business in American Society, Oxford U.P., 2015.......Guest Post to the Society for U.S. Intellectual History Blog. Brief introduction to the book Progressive Business: An Intellectual History of the Role of Business in American Society, Oxford U.P., 2015....

  19. Yield stress materials in soft condensed matter

    Science.gov (United States)

    Bonn, Daniel; Denn, Morton M.; Berthier, Ludovic; Divoux, Thibaut; Manneville, Sébastien

    2017-07-01

    A comprehensive review is presented of the physical behavior of yield stress materials in soft condensed matter, which encompasses a broad range of materials from colloidal assemblies and gels to emulsions and non-Brownian suspensions. All these disordered materials display a nonlinear flow behavior in response to external mechanical forces due to the existence of a finite force threshold for flow to occur: the yield stress. Both the physical origin and rheological consequences associated with this nonlinear behavior are discussed and an overview is given of experimental techniques available to measure the yield stress. Recent progress is discussed concerning a microscopic theoretical description of the flow dynamics of yield stress materials, emphasizing, in particular, the role played by relaxation time scales, the interplay between shear flow and aging behavior, the existence of inhomogeneous shear flows and shear bands, wall slip, and nonlocal effects in confined geometries.

  20. HTGR Generic Technology Program. Materials technology reactor operating experience medium-enriched-uranium fuel development. Quarterly progress report for the period ending April 30, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Kaae, J. L.; Lai, G. Y.; Thompson, L. D.; Sheehan, J. E.; Rosenwasser, S. N.; Johnson, W. R.; Li, C. C.; Pieren, W. R.; Smith, A. B.; Holko, K. H.; Baenteli, G. J.; Cheung, K. C.; Orr, J. D.; Potter, R. C.; Baxter, A.; Bell, W.; Lane, R.; Wunderlich, R. G.; Neylan, A. J.

    1978-05-01

    The work reported includes the development of the materials properties data base for noncore components, plant surveillance and testing performed at Fort St. Vrain, and work to demonstrate the feasibility of using medium-enriched fuel in Fort St. Vrain. Studies and analyses plus experimental procedures and results are discussed and data are presented.

  1. Morphologies of omega band auroras

    Science.gov (United States)

    Sato, Natsuo; Yukimatu, Akira Sessai; Tanaka, Yoshimasa; Hori, Tomoaki

    2017-08-01

    We examined the morphological signatures of 315 omega band aurora events observed using the Time History of Events and Macroscale Interactions during Substorm ground-based all-sky imager network over a period of 8 years. We find that omega bands can be classified into the following three subtypes: (1) classical (O-type) omega bands, (2) torch or tongue (T-type) omega bands, and (3) combinations of classical and torch or tongue (O/T-type) omega bands. The statistical results show that T-type bands occur the most frequently (45%), followed by O/T-type bands (35%) and O-type bands (18%). We also examined the morphologies of the omega bands during their formation, from the growth period to the declining period through the maximum period. Interestingly, the omega bands are not stable, but rather exhibit dynamic changes in shape, intensity, and motion. They grow from small-scale bumps (seeds) at the poleward boundary of preexisting east-west-aligned auroras, rather than via the rotation or shear motion of preexisting east-west-aligned auroras, and do not exhibit any shear motion during the periods of auroral activity growth. Furthermore, the auroral luminosity is observed to increase during the declining period, and the total time from the start of the growth period to the end of the declining period is found to be about 20 min. Such dynamical signatures may be important in determining the mechanism responsible for omega band formation.

  2. Wide band interferometry for thickness measurement

    Science.gov (United States)

    Costantino, Santiago; Martinez, Oscar E.; Torga, Jorge R.

    2003-04-01

    In this work we present the concept of wide band interferometry as opposed to white-light interferometry to introduce a thickness measurement method that gains precision when the bandwidth is reduced to an adequate compromise in order to avoid the distortions arising from the material dispersion. The use of the widest possible band is a well established dogma when the highest resolution is desired in distance measurements with white-light interferometry. We will show that the dogma falls when thickness measurements must be carried out due to material dispersion. In fact the precise knowledge of the frequency dependence of the refractive index is essential for adequate thickness retrieval from the optical experiments. The device we present is also useful to obtain the group refractive index that is necessary to calculate the absolute thickness value. As an example, we show the spreading of a silicone oil on a reference surface in real time.

  3. Wide band ENDOR spectrometer

    International Nuclear Information System (INIS)

    Mendonca Filho, C.

    1973-01-01

    The construction of an ENDOR spectrometer operating from 0,5 to 75 MHz within a single band, with ore Klystron and homodine detection, and no fundamental changes on the electron spin resonance spectrometer was described. The ENDOR signal can be detected both by amplitude modulation of the frequency field, or direct detection of the ESR output, which is taken to a signal analyser. The signal-to-noise ratio is raised by averaging rather than filtering avoiding the use of long time constants, providing natural line widths. The experimental apparatus and the spectra obtained are described. A discussion, relating the ENDOR line amplitudes with the experimental conditions is done and ENDOR mechanism, in which there is a relevant presence of cross relaxation is proposed

  4. Wide Band Artificial Pulsar

    Science.gov (United States)

    Parsons, Zackary

    2017-01-01

    The Wide Band Artificial Pulsar (WBAP) is an instrument verification device designed and built by the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virgina. The site currently operates the Green Bank Ultimate Pulsar Processing Instrument (GUPPI) and the Versatile Green Bank Astronomical Spectrometer (VEGAS) digital backends for their radio telescopes. The commissioning and continued support for these sophisticated backends has demonstrated a need for a device capable of producing an accurate artificial pulsar signal. The WBAP is designed to provide a very close approximation to an actual pulsar signal. This presentation is intended to provide an overview of the current hardware and software implementations and to also share the current results from testing using the WBAP.

  5. Progress report on research and development work 1991 of the Institute of Genetics and Toxicology of Fissionable Materials, Karlsruhe Nuclear Research Center

    International Nuclear Information System (INIS)

    1991-03-01

    The present annual report describes the results of research work done by the Institute of Genetics and Toxicology of Fissionable Materials (IGT) in 1991. The following eight subjects were dealt with: genetic repair; genetic regulation; biological carcinogenesis; molecular genetics of eukaryontic genes; genetic mouse models for human illnesses; radiation toxicology of actinides; molecular and cellular environmental toxicology, and in vivo fractionation and speciation of actinides. (MG) [de

  6. Adsorption and diffusion of fluids in well-characterized adsorbent materials. Renewal progress report, August 1, 1995 to January 31, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Gubbins, Keith E.; Cracknell, R.F.; Maddox, M.; Nicholson, D.

    1999-08-01

    This is an invited review paper describing recent advances in molecular simulation and theory of fluids confined within well-characterized porous materials. Methods and intermolecular potential models are described. This is followed by showing results for several examples, including supercritical methane adsorption in carbons, adsorption and diffusion of argon in VPI-5, adsorption of argon in silicalite-1, nitrogen adsorption in MCM-41, and adsorption of argon and nitrogen in carbon nanotubes.

  7. General corrosion, irradiation-corrosion, and environmental-mechanical evaluation of nuclear-waste-package structural-barrier materials. Progress report

    International Nuclear Information System (INIS)

    Westerman, R.E.; Pitman, S.G.; Nelson, J.L.

    1982-09-01

    Pacific Northwest Laboratory is studying the general corrosion, irradiation-corrosion, and environmentally enhanced crack propagation of five candidate materials in high-temperature aqueous environments simulating those expected in basalt and tuff repositories. The materials include three cast ferrous materials (ductile cast iron and two low-alloy Cr-Mo cast steels) and two titanium alloys, titanium Grade 2 (commercial purity) and Grade 12 (a Ti-Ni-Mo alloy). The general corrosion results are being obtained by autoclave exposure of specimens to slowly replenished simulated ground water flowing upward through a bed of the appropriate crushed rock (basalt or tuff), which is maintained at the desired test temperature (usually 250 0 C). In addition, tests are being performed in deionized water. Metal penetration rates of iron-base alloys are being derived by stripping off the corrosion product film and weighing the specimen after the appropriate exposure time. The corrosion of titanium alloy specimens is being determined by weight gain methods. The irradiation-corrosion studies are similar to the general corrosion tests, except that the specimen-bearing autoclaves are held in a 60 Co gamma radiation field at dose rates up to 2 x 10 6 rad/h. For evaluating the resistance of the candidate materials to environmentally enhanced crack propagation, three methods are being used: U-bend and fracture toughness specimens exposed in autoclaves; slow strain rate studies in repository-relevant environments to 300 0 C; and fatigue crack growth rate studies at ambient pressure and 90 0 C. The preliminary data suggest a 1-in. corrosion allowance for iron-base barrier elements intended for 1000-yr service in basalt or tuff repositories. No evidence has yet been found that titanium Grade 2 or Grade 12 is susceptible to environmentally induced crack propagation or, by extension, to stress corrosion cracking

  8. Synthesis, evaluation, and defect compensation of tetrahedral glasses as possible solar cell materials. Quarterly technical progress report No. 2, May 1-July 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Rauh, R D

    1979-09-01

    Work performed on the project to synthesize A/sup II/B/sup IV/C/sub 2//sup V/ glasses and evaluate their potential use as solar cell materials is described. The major effort was directed towards preparation of these films by thermal evaporation of compounds synthesized during the first quarter. Films were produced from CdAs/sub 2/, CdSnAs/sub 2/, CdSiAs/sub 2/, ZnSiAs/sub 2/ and ZnAs/sub 2/. Only films from the last compound had a stoichiometry comparable to the starting material. The ternary films were deficient in the group IV element and films produced from CdAs/sub 2/ indicated the sample had undergone extensive decomposition. In addition to having good stoichiometries, the x-ray analysis of the ZnAs/sub 2/ films indicated they were amorphous. The work thus represents the first reported results of preparation of amorphous films of ZnAs/sub 2/. The optical and electrical properties of this material will be characterized in the next quarter.

  9. On the persistence of adiabatic shear bands

    Directory of Open Access Journals (Sweden)

    Bassim M.N.

    2012-08-01

    Full Text Available It is generally agreed that the initiation and development of adiabatic shear bands (ASBs are manifestations of damage in metallic materials subjected to high strain rates and large strains as those due to impact in a Hopkinson Bar system. Models for evolution of these bands have been described in the literature. One question that has not received attention is how persistent these bands are and whether their presence and effect can be reversed or eliminated by using a process of thermal (heat treatment or thermo-mechanical treatment that would relieve the material from the high strain associated with ASBs and their role as precursors to crack initiation and subsequent failure. Since ASBs are more prevalent and more defined in BCC metals including steels, a study was conducted to investigate the best conditions of generating ASBs in a heat treatable steel, followed by determining the best conditions for heat treatment of specimens already damaged by the presence of ASBs in order to relieve the strains due to ASBs and restore the material to an apparent microstructure without the “scars” due to the previous presence of ASBs. It was found that heat treatment achieves the curing from ASBs. This presentation documents the process undertaken to achieve this objective.

  10. Progress towards vertical transport study of proton-irradiated InAs/GaSb type-II strained-layer superlattice materials for space-based infrared detectors using magnetoresistance measurements

    Science.gov (United States)

    Malone, Mitchell C.; Morath, Christian P.; Fahey, Stephen; Klein, Brianna; Cowan, Vincent M.; Krishna, Sanjay

    2015-09-01

    InAs/GaSb type-II strained-layer superlattice (T2SLS) materials are being considered for space-based infrared detector applications. However, an inadequate understanding of the role of carrier transport, specifically the vertical mobility, in the radiation tolerance of T2SLS detectors remains. Here, progress towards a vertical transport study of proton-irradiated, p-type InAs/GaSb T2SLS materials using magnetoresistance measurements is reported. Measurements in the growth direction of square mesas formed from InAs/GaSb superlattice material were performed using two distinct contact geometries in a Kelvin mode setup at variable magnetic fields, ranging from -9 T to 9 T, and temperatures, ranging from 5 K and 300 K. The results here suggested multi-carrier conduction and a field-dependent series resistance from the contact layer were present. The implications of these results and the plans for future magnetoresistance measurements on proton-irradiated T2SLS materials are discussed.

  11. Investigation of test methods, material properties, and processes for solar cell encapsulants. Eighteenth quarterly progress report, August 12-November 12, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Willis, P. B.; Baum, B.; Davis, M.

    1980-12-01

    The goal of this program is to identify, evaluate, and recommend encapsulant materials and processes for the production of cost-effective, long-life solar cell modules. A survey was made of elastomers for use as gaskets for the photovoltaic module. Of the wide variety of materials examined EPDM offered the optimum combination of low compression set and low cost. The preference for EPDM is borne out by its long history of use as an automobile gasket. The commercial availability of materials that would be useful for sealants between the edge of the module and the gasket was investigated. Butyl sealants have the best combination of physical properties, low cost and a well-documented history of performance. A preferred composition has not yet been identified. One laminating type pottant ethylene/methyl acrylate copolymer (EMA), and two casting polymers, polybutyl acrylate and polyurethane, have been under investigation this past quarter. An EMA formulation has been developed which is easily extrudable and cures to a high gel content. So far only one commercial US source (Quinn) of aliphatic polyurethane has been located. Work is continuing to improve reaction rate as well as to eliminate source(s) of bubble formation during module fabrication. Considerable effort was spent in developing an improved polybutyl acrylate casting formulation providing high gel. Many viable curing systems are now available: however, the best formulation considering physical properties, freedom from bubbles as well as cure time utilizes Lupersol II (aliphatic peroxide) initiator. This initiator gives the desired gel after 20 minute cure at 45/sup 0/C or 12 minute cure at 55/sup 0/C.

  12. Progress in physical chemistry

    CERN Document Server

    Hempelmann, Rolf

    2008-01-01

    Progress in Physical Chemistry is a collection of recent ""Review Articles"" published in the ""Zeitschrift für Physikalische Chemie"". The second volume of Progress in Physical Chemistry is a collection of thematically closely related minireview articles written by the members of the Collaborative Research Centre (SFB) 277 of the German Research Foundation (DFG). These articles are based on twelve years of intense coordinated research efforts. Central topics are the synthesis and the characterization of interface-dominated, i.e. nanostructured materials, mainly in the solid state but also as

  13. Development of an x-ray beam line at the NSLS for studies in materials science using x-ray absorption spectroscopy: Annual progress report

    International Nuclear Information System (INIS)

    Sayers, D.E.

    1986-01-01

    Although only in operation since May, 1985, the X-11 participation research team (PRT) at the NSLS has already demonstrated that it is one of the leading centers of x-ray absorption spectroscopy (XAS). During this time, results have been obtained and programs initiated in a number of areas, for example: interfaces, including deposited metal-metal and metal-semiconductor systems, multilayers and ion implanted layers; electrochemical systems, including Pt electrode fuel cells, Ni oxide battery electrodes, conducting polymers, passivation and corrosion; catalysts, including highly-dispersed supported metal catalysts and zeolite systems; quasi-crystals, heavy fermion systems, uranium and neptunium compounds, rare gas clusters, disordered metals and semiconductors, ferroelectric transition; and, biological systems and related models, including synthetic porphyrins and a number of metalloproteins. In concert with these scientific results have been a number of developments involving the technique itself. These include implementation of unique optical systems on both the A and B lines for optical performance over their designed energy ranges, advances in experimental capability, particular in glancing angle studies, optimization of ion chambers for surface studies, the improvement of electron yield detectors, and improved software for data acquisition and analysis. This report emphasizes some of the research highlights and significant developments of our PRT which occurred during the past year. A detailed bibliography of papers and talks resulting from work done at our beamline and the progress reports for our PRT which were in the 1985 NSLS Annual Report are appended

  14. Prediction of the behavior of structural materials under irradiation through modeling of the microstructure. Progress report, November 1, 1980-October 31, 1981. Final report

    International Nuclear Information System (INIS)

    Wolfer, W.G.

    1981-10-01

    The research carried out over the period of about three years falls into three categories: effects of point-defect interactions on the formation of voids, dislocation loops, and network dislocations, during irradiation, and the consequences on the mechanical properties of structural materials; the development of a new mathematical tool to describe the evolution of systems far from a thermodynamic equilibrium state; and the development and exploration of a new technique to measure mechanically and non-destructively the creep damage, or the grain-boundary cavity formation, which is the cause of high-temperature stress rupture

  15. Enforcement actions: Significant actions resolved material licensees (non-medical). Volume 14, No. 1, Part 3, Quarterly progress report, January--March 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1995) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to Material Licensees (non-Medical) with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication.

  16. Enforcement actions: Significant actions resolved, material licensees (non-medical). Quarterly progress report, July--September 1994: Volume 13, Number 3, Part 3

    International Nuclear Information System (INIS)

    1994-12-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1994) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees (non-medical) with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated the managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  17. Enforcement actions: Significant actions resolved material licensees (non-medical). Volume 14, No. 1, Part 3, Quarterly progress report, January--March 1995

    International Nuclear Information System (INIS)

    1995-05-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1995) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to Material Licensees (non-Medical) with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  18. Enforcement actions: Significant actions resolved, material licensees. Semiannual progress report, July--December 1995: Volume 14, Numbers 3 and 4, Part 3

    International Nuclear Information System (INIS)

    1996-02-01

    This compilation summarizes significant enforcement actions that have been resolved during the period (July--December 1995) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to material licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  19. The synthesis of new donor–acceptor polymers containing the 2,3-di(2-furyl) quinoxaline moiety: Fast-switching, low-band-gap, p- and n-dopable, neutral green-colored materials

    International Nuclear Information System (INIS)

    Xu, Zhen; Wang, Min; Fan, Weiyu; Zhao, Jinsheng; Wang, Huaisheng

    2015-01-01

    Highlights: • Three D-A type polymers based on 2,3-di(2-furyl) quinoxaline were synthesized and characterized. • The structure of substitution influences electrochromic properties of the polymers • All three polymers are both p- and n-type dopable and show excellent electrochromic properties. - Abstract: Three donor–acceptor type π-conjugated polymers were synthesized electrochemically:poly[2,3-di(2-furyl)-5,8-bis (2-(3,4-ethylenedioxythiophene)) quinoxaline] (PFETQ), poly[2,3-di(2-furyl)-5,8-bis(2-thienyl) quinoxaline] (PFTQ) and poly[2,3-di(2-furyl)-5,8-bis(2-(3-methoxythiophene)) quinoxaline] (PFMTQ). All of the synthesized polymers, contained the 2,3-di(2-furyl) quinoxaline moiety in the backbone as the acceptor unit and different thiophene derivatives as the donor units. The electroactivity of the monomers and the electrochemical properties of their polymers were investigated by cyclic voltammetry. The presence of the strong electron-donating ethylenedioxy and methoxy groups on the aromatic structure increased the electron density. Thus, the oxidation potential of FETQ and FMTQ shifted to a lower value than that of FTQ. The optical properties of the polymers were investigated by UV–vis–NIR spectroscopy. Both PFETQ and PFMTQ reveal two distinct absorption bands in the red and blue regions of the visible spectrum, while PFTQ has only one dominant wavelength at 596 nm in the visible region. The colorimetry analysis revealed that while PFTQ has a light blue color, PFETQ and PFMTQ are green in the neutral state. The optical band gaps, defined as the onset of the π–π* transition, were found to be 1.15 eV for PFETQ, 1.2 eV for PFMTQ and 1.34 eV for PFTQ. Moreover, all three polymers showed both n-doping and fast switching times

  20. Annual Technical Progress Report of Radioisotope Power Systems Materials Production and Technology Program Tasks for October 1, 2007 Through September 30,2008

    Energy Technology Data Exchange (ETDEWEB)

    King, James F [ORNL

    2009-04-01

    The Office of Radioisotope Power Systems (RPS) of the Department of Energy (DOE) provides RPS for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration (NASA) for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of RPS for fiscal year (FY) 2008. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new RPS.

  1. Annual Technical Progress Report of the Radioisotope Power Systems Materials Production and Technology Program Tasks for October 1, 2008 through September 30, 2009

    Energy Technology Data Exchange (ETDEWEB)

    King, James F [ORNL

    2010-05-01

    The Office of Space and Defense Power Systems of the U. S. Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators (RTG) were supplied by the DOE to the National Aeronautics and Space Administration (NASA) for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, the Oak Ridge National Laboratory (ORNL) produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. ORNL has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2009. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new RPS.

  2. ANNUAL TECHNICAL PROGRESS REPORT OF RADIOISOTOPE POWER SYSTEMS MATERIALS PRODUCTION AND TECHNOLOGY PROGRAM TASKS FOR OCTOBER 1, 2010 THROUGH SEPTEMBER 30, 2011

    Energy Technology Data Exchange (ETDEWEB)

    King, James F [ORNL

    2012-05-01

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration (NASA) for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, the Oak Ridge National Laboratory (ORNL) produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. These components were also produced for the Pluto New Horizons and Mars Science Lab missions launched in January 2006 and November 2011respectively. The ORNL has been involved in developing materials and technology and producing components for the DOE for nearly four decades. This report reflects program guidance from the Office of RPS for fiscal year (FY) 2011. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new RPS. Work has also been initiated to establish fabrication capabilities for the Light Weight Radioisotope Heater Units.

  3. Semi-Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for October 1, 2001 Through March 31, 2002

    Energy Technology Data Exchange (ETDEWEB)

    J. P. Moore, JPM

    2002-05-22

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. For the Cassini Mission, for example, ORNL was involved in the production of carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS). This report has been divided into three sections to reflect program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2002. The first section deals primarily with maintenance of the capability to produce flight quality (FQ) CBCF insulator sets, iridium alloy blanks and foil, and CVS. In all three cases, production maintenance is assured by the manufacture of limited quantities of FQ components. The second section deals with several technology activities to improve the manufacturing processes, characterize materials, or to develop technologies for new radioisotope power systems. The last section is dedicated to studies related to the production of {sup 238}Pu.

  4. Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for October 1, 2002 Through September 30, 2003

    Energy Technology Data Exchange (ETDEWEB)

    King, J.F.

    2004-05-18

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. For the Cassini Mission, for example, ORNL was involved in the production of carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS). This report has been divided into three sections to reflect program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2003. The first section deals primarily with maintenance of the capability to produce flight quality (FQ) CBCF insulator sets, iridium alloy blanks and foil, and CVS. In all three cases, production maintenance is assured by the manufacture of limited quantities of FQ components. The second section deals with several technology activities to improve the manufacturing processes, characterize materials, or to develop technologies for new radioisotope power systems. The last section is dedicated to studies related to the production of {sup 238}Pu.

  5. Recent progress in InAs/InP quantum dash nanostructures and devices

    KAUST Repository

    Ooi, Boon S.

    2016-03-24

    In this talk, we will give an outline and introduction to the broad inter-band emission devices focusing on the InAs/InP quantum dash material system, device physics and establishment of ultrabroad stimulated emission behavior. In addition, technologies for growing these nanostructures as well as engineer the bandgap of quantum dash based system using epitaxy growth techniques and postgrowth intermixing methods will be presented. At device level, we will focus our discussion on our recent progress in extending the ultra-broad lasing emission from quantum dash lasers, and achievements in broad gain semiconductor optical amplifiers (SOA), mode locked lasers, comb-lasers, wide band superluminsect diodes fabricated on this material system. © 2015 IEEE.

  6. The possible mass region for shears bands and chiral doublets

    Energy Technology Data Exchange (ETDEWEB)

    Meng, J. [Institute of Physical and Chemical Research, Wako, Saitama (Japan); Frauendorf, S.

    1998-03-01

    The Tilted Axis Cranking (TAC) theory is reviewed. The recent progress of TAC for triaxial deformed nuclei is reported. More emphasis has been paid to the new discovered phenomena - chiral doublets and their explanation. The possible mass region for the shears bands and chiral doublets and their experimental signature are discussed. (author)

  7. Tuning quantum dot luminescence below the bulk band gap using tensile strain.

    Science.gov (United States)

    Simmonds, Paul J; Yerino, Christopher D; Sun, Meng; Liang, Baolai; Huffaker, Diana L; Dorogan, Vitaliy G; Mazur, Yuriy; Salamo, Gregory; Lee, Minjoo Larry

    2013-06-25

    Self-assembled quantum dots (SAQDs) grown under biaxial tension could enable novel devices by taking advantage of the strong band gap reduction induced by tensile strain. Tensile SAQDs with low optical transition energies could find application in the technologically important area of mid-infrared optoelectronics. In the case of Ge, biaxial tension can even cause a highly desirable crossover from an indirect- to a direct-gap band structure. However, the inability to grow tensile SAQDs without dislocations has impeded progress in these directions. In this article, we demonstrate a method to grow dislocation-free, tensile SAQDs by employing the unique strain relief mechanisms of (110)-oriented surfaces. As a model system, we show that tensile GaAs SAQDs form spontaneously, controllably, and without dislocations on InAlAs(110) surfaces. The tensile strain reduces the band gap in GaAs SAQDs by ~40%, leading to robust type-I quantum confinement and photoluminescence at energies lower than that of bulk GaAs. This method can be extended to other zinc blende and diamond cubic materials to form novel optoelectronic devices based on tensile SAQDs.

  8. Investigation of test methods material properties, and processes for solar cell encapsulants. Fifteenth quarterly progress report, November 12, 1979-February 12, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Willis, P. B.; Baum, B.

    1980-03-01

    The goal of this program is to identify, evaluate, and recommend encapsulant materials and processes for the production of cost-effective, long-life solar cell modules. Work performed during this quarter included the development of anti-blocking treatments for EVA sheet intended for use as a lamination pottant. Initial evaluation studies were begun on a new pottant compound, polybutyl acrylate, to assess its preparation and handling characteristics. Corrosion studies using a standard salt spray test wre conducted to determine the degree of protection afforded to a number of metals when encapsulated in candidate pottant compounds. Pottants and outer cover candidates were exposed to intervals of accelerated uv stress aging using the RS/4 fluorescent sunlamp. Results are discussed. (WHK)

  9. NERI Quarterly Progress Report -- April 1 - June 30, 2005 -- Development of a Supercritical Carbon Dioxide Brayton Cycle: Improving PBR Efficiency and Testing Material Compatibility

    International Nuclear Information System (INIS)

    Chang Oh

    2005-01-01

    The objective of this research is to improve a helium Brayton cycle and to develop a supercritical carbon dioxide Brayton cycle for the Pebble Bed Reactor (PBR) that can also be applied to the Fast Gas-Cooled Reactor (FGR) and the Very-High-Temperature Gas-Cooled Reactor (VHTR). The proposed supercritical carbon dioxide Brayton cycle will be used to improve the PBR, FGR, and VHTR net plant efficiency. Another objective of this research is to test materials to be used in the power conversion side at supercritical carbon dioxide conditions. Generally, the optimized Brayton cycle and balance of plant (BOP) to be developed from this study can be applied to Generation-IV reactor concepts. Particularly, we are interested in VHTR because it has a good chance of being built in the near future

  10. The Use of Alternative Raw Material in Production of Pastry Products as a Progressive Direction in Creating the Products of High Biological Value

    Directory of Open Access Journals (Sweden)

    Janа Bachinska

    2017-02-01

    Full Text Available This paper examines the impact of the use of alternative vegetable raw materials in the manufacture of pastry products with high biological value; it presents the results of evaluation of commodity of the developed products and compares them with the main samples presented in Kharkiv trade network. The feasibility of using a mixture of fiber and pumpkin seeds in the technology of pastry production to extend the range of confectionery products of high biological value and products with reduced calories has been proved. Adding the mixture of fiber and pumpkin seeds to biscuits and cakes positively affected the chemical composition of the ready-made product, saturating it with useful and necessary to human body mineral elements, vitamins, dietary fiber.

  11. Development of an x-ray beam line at the NSLS for studies in materials science using x-ray absorption spectroscopy: Annual progress report

    International Nuclear Information System (INIS)

    Sayers, D.E.

    1987-01-01

    The research programs reported span virtually the entire range of condensed matter studies involving the fields of solid state physics, chemistry, electrochemistry, materials science and biochemistry. Results are discussed for various groups. Topics reported include work on amorphous chalcogenide semiconductors, particularly photostructural changes, kinetics of structural changes and rapid quenching, bond strengths, force constants and phonons. Also reported are temperature dependent EXAFS studies of bonding in high temperature alloys, amorphous systems, disordered alloys and studies of resolve electronic structure, EXAFS and XANES studies of permanent magnet systems based on Nd 2 Fe 14 B, glancing angle EXAFS study of Nb/Al and Nb/Si interfacial systems, x-ray absorption of krypton-implanted solids and high dose implants into silicon, and x-ray absorption and EXAFS studies of superconducting oxide compounds of Cu and related magnetic systems. Work is also reported on XAFS measurements on the icosahedral phase

  12. Hazardous materials in aquatic environments of the Mississippi River Basin Project management. Technical quarterly progress report, April 1, 1996--June 30, 1996

    Energy Technology Data Exchange (ETDEWEB)

    McLachlan, J.; Ide, C.F.; O`Connor, S.

    1996-08-01

    This quarterly report summarizes accomplishments for the Project examining hazardous materials in aquatic environments of the Mississippi River Basin. Among the many research areas summarized are the following: assessment of mechanisms of metal-induced reproductive toxicity in aquatic species as a biomarker of exposure; hazardous wastes in aquatic environment;ecological sentinels of aquatic contamination in the lower Mississippi River System; remediation of selected contaminants; rapid on-site immunassay for heavy metal contamination; molecular mechanisms of developmental toxicity induced by retinoids and retinoid-like molecules; resuseable synthetic membranes for the removal of aromatic and halogenated organic pollutants from waste water; Effects of steroid receptor activation in neurendocrine cell of the mammalian hypothalamus; modeling and assessment of environmental quality of louisiana bayous and swamps; enhancement of environmental education. The report also contains a summary of publications resulting from this project and an appendix with analytical core protocals and target compounds and metals.

  13. Optimization of Beam Properties with Respect to Maximum Band-Gap

    DEFF Research Database (Denmark)

    Halkjær, Søren; Sigmund, Ole

    2004-01-01

    We study numerically the frequency band-gap phenomenon for bending waves in an infinite periodic beam. The outcome of the analysis is then subjected to an optimization problem in order to maximize these band-gaps. The band-gap maximization may be performed with respect to material parameters and ...

  14. Progress report

    International Nuclear Information System (INIS)

    1999-01-01

    This report presents a selection of results that were obtained by CEREM's teams in 1999. These results are arranged into a series of themes: i) preparation, fabrication and forming of materials, ii) surface treatment, iii) energy storage, iv) remote handling equipment, v) corrosion, vi) physical properties of materials, vii) non-destructive testing, and viii) applications of ionizing radiations

  15. Band bowing and the direct-to-indirect crossover in random BAlN alloys

    Science.gov (United States)

    Shen, Jimmy-Xuan; Wickramaratne, Darshana; Van de Walle, Chris G.

    2017-11-01

    Boron-containing nitride alloys such as BAlN are being explored as novel members of the nitride family of materials for electronic and optoelectronic applications. Using hybrid density functional calculations we determine structural properties, band gaps, and band-gap bowing of random wurtzite BAlN alloys. The fundamental band gap of BN is indirect while AlN is a direct-band-gap semiconductor. This leads to a crossover in the band gap from direct to indirect at 28 % boron. We find that the direct band gap experiences extreme bowing, leading to a fundamental gap that changes very little up to 17% boron incorporation.

  16. Fundamentals and applications of magnetic materials

    CERN Document Server

    Krishnan, Kannan M

    2016-01-01

    Students and researchers looking for a comprehensive textbook on magnetism, magnetic materials and related applications will find in this book an excellent explanation of the field. Chapters progress logically from the physics of magnetism, to magnetic phenomena in materials, to size and dimensionality effects, to applications. Beginning with a description of magnetic phenomena and measurements on a macroscopic scale, the book then presents discussions of intrinsic and phenomenological concepts of magnetism such as electronic magnetic moments and classical, quantum, and band theories of magnetic behavior. It then covers ordered magnetic materials (emphasizing their structure-sensitive properties) and magnetic phenomena, including magnetic anisotropy, magnetostriction, and magnetic domain structures and dynamics. What follows is a comprehensive description of imaging methods to resolve magnetic microstructures (domains) along with an introduction to micromagnetic modeling. The book then explores in detail size...

  17. Development and applications of photosensitive device systems to studies of biological and organic materials: Progress report for period June 1964-December 1986

    International Nuclear Information System (INIS)

    Reynolds, G.T.; Gruner, S.M.

    1987-01-01

    A broad range of devices based on electro-optical technologies were developed and applied to the study of biological and other organic materials, ranging from single cell organisms to complex lipid liquid crystals. The detector systems developed have incorporated state of the art image intensifiers, vidicons, and solid state detectors. A major emphasis has been on the development of an x-ray image intensifier system suitable for diffraction experiments at high flux synchrotron sources. The detector has been applied to time resolved studies of lipid membrane phase transitions, with time resolution of the order of 10 msec. In addition, the x-ray detectors have been used to discover 3 cubic phases in the 1-methylphosphatidylethanolamine-water system, permitting a refinement of the phase transition theory developed earlier. The detectors have also been applied to low level light detection of selected luminescence phenomena. In particular, the cellular sources of bioluminescence in many organisms have been discovered, along with detailed information on the spectral distributions. Using the photoprotein aequorin and fluorescence techniques detailed studies have been made of free calcium release and uptake in a number of important metabolic processes. 11 refs

  18. Strain sensitivity of band gaps of Sn-containing semiconductors

    DEFF Research Database (Denmark)

    Li, Hong; Castelli, Ivano Eligio; Thygesen, Kristian Sommer

    2015-01-01

    Tuning of band gaps of semiconductors is a way to optimize materials for applications within photovoltaics or as photocatalysts. One way to achieve this is through applying strain to the materials. We investigate the effect of strain on a range of Sn-containing semiconductors using density...

  19. Two-dimensional microwave band-gap structures of different ...

    Indian Academy of Sciences (India)

    Abstract. We report the use of low dielectric constant materials to form two- dimensional microwave band-gap structures for achieving high gap-to-midgap ratio. The variable parameters chosen are the lattice spacing and the geometric structure. The se- lected geometries are square and triangular and the materials chosen ...

  20. Dendrometer bands made easy: using modified cable ties to measure incremental growth of trees

    Science.gov (United States)

    Anemaet, Evelyn R.; Middleton, Beth A.

    2013-01-01

    Dendrometer bands are a useful way to make sequential repeated measurements of tree growth, but traditional dendrometer bands can be expensive, time consuming, and difficult to construct in the field. An alternative to the traditional method of band construction is to adapt commercially available materials. This paper describes how to construct and install dendrometer bands using smooth-edged, stainless steel, cable tie banding and attachable rollerball heads. As a performance comparison, both traditional and cable tie dendrometer bands were installed on baldcypress trees at the National Wetlands Research Center in Lafayette, Louisiana, by both an experienced and a novice worker. Band installation times were recorded, and growth of the trees as estimated by the two band types was measured after approximately one year, demonstrating equivalence of the two methods. This efficient approach to dendrometer band construction can help advance the knowledge of long-term tree growth in ecological studies.

  1. Dual-band infrared camera

    Science.gov (United States)

    Vogel, H.; Schlemmer, H.

    2005-10-01

    Every year, numerous accidents happen on European roads due to bad visibility (fog, night, heavy rain). Similarly, the dramatic aviation accidents of year 2001 in Milan and Zurich have reminded us that aviation safety is equally affected by reduced visibility. A dual-band thermal imager was developed in order to raise human situation awareness under conditions of reduced visibility especially in the automotive and aeronautical context but also for all transportation or surveillance tasks. The chosen wavelength bands are the Short Wave Infrared SWIR and the Long Wave Infrared LWIR band which are less obscured by reduced visibility conditions than the visible band. Furthermore, our field tests clearly show that the two different spectral bands very often contain complementary information. Pyramidal fusion is used to integrate complementary and redundant features of the multi-spectral images into a fused image which can be displayed on a monitor to provide more and better information for the driver or pilot.

  2. Propulsion materials

    Energy Technology Data Exchange (ETDEWEB)

    Wall, Edward J. [U.S. Dept. of Energy, Washington, D.C. (United States); Sullivan, Rogelio A. [U.S. Dept. of Energy, Washington, D.C. (United States); Gibbs, Jerry L. [U.S. Dept. of Energy, Washington, D.C. (United States)

    2008-01-01

    The Department of Energy’s (DOE’s) Office of Vehicle Technologies (OVT) is pleased to introduce the FY 2007 Annual Progress Report for the Propulsion Materials Research and Development Program. Together with DOE national laboratories and in partnership with private industry and universities across the United States, the program continues to engage in research and development (R&D) that provides enabling materials technology for fuel-efficient and environmentally friendly commercial and passenger vehicles.

  3. Using a profiling process to insure program quality: Volume II - support materials. Final progress report, May 15, 1991--November 14, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Kaser, J.S.; Roody, D.S.; Raizen, S.A.

    1996-11-01

    Between 1990 and 1995 the U.S. Department of Energy (DOE) and the National Center for Improving Science Education (National Center) developed a system for ongoing evaluation of K-12 educational programs in the DOE-supported national energy Laboratories. As part of the formative evaluation component of this collaborative endeavor, field staff in the Laboratories began creating profiles of their programs. However, many individuals within DOE Headquarters were not familiar with this profiling process and were unprepared to use the valuable information that the profiles generated. This manual was produced to orient Headquarters staff to profiling. It focuses on how Headquarters staff can use the profiling process to help their funded programs establish and/or maintain high quality. Its purpose, then, is not to train Headquarters staff to become proficient in profiling, but to show them how to draw on the Laboratories` use of profiling to bring about program improvement. Profiling is the process of systematically examining and describing a program`s elements against a set of components that define Effective Practice. The instrument used to capture the data for analysis is called a template, and most of this manual focuses on the templates and how to read and interpret them. However, since it is important to understand these data in context, the authors also describe what should accompany each template in a complete profiling packet and offer guidelines for reviewing complete packets and providing feedback to program managers. This document consists of Support Materials for the manual: exercise answer keys; templates; guidelines for reviewing templates; a complete profiling packet; guidelines for the trainer.

  4. Astrobiology Learning Progressions: Linking Astrobiology Concepts with the 3D Learning Paradigm of NGSS

    Science.gov (United States)

    Scalice, D.; Davis, H. B.; Leach, D.; Chambers, N.

    2016-12-01

    The Next Generation Science Standards (NGSS) introduce a Framework for teaching and learning with three interconnected "dimensions:" Disciplinary Core Ideas (DCI's), Cross-cutting Concepts (CCC's), and Science and Engineering Practices (SEP's). This "3D" Framework outlines progressions of learning from K-12 based on the DCI's, detailing which parts of a concept should be taught at each grade band. We used these discipline-based progressions to synthesize interdisciplinary progressions for core concepts in astrobiology, such as the origins of life, what makes a world habitable, biosignatures, and searching for life on other worlds. The final product is an organizing tool for lesson plans, learning media, and other educational materials in astrobiology, as well as a fundamental resource in astrobiology education that serves both educators and scientists as they plan and carry out their programs for learners.

  5. Large sonic band gaps in 12-fold quasicrystals

    Science.gov (United States)

    Lai, Yun; Zhang, Xiangdong; Zhang, Zhao-Qing

    2002-05-01

    The sonic band-gap structures of 12-fold symmetry quasicrystals consisting of rigid cylinders in air are investigated by using the multiple scattering method. Large full gaps are found in this system owing to its high symmetry. At filling fractions between 0.2 and 0.4, this 12-fold square-triangle tiling is much better for the realization of sonic band gaps than the square or triangular lattice. This makes the 12-fold quasicrystal a promising structure for acoustic-wave band-gap materials.

  6. Community-based Music Education: Influences of Industrial Bands in the American South.

    Science.gov (United States)

    LeCroy, Hoyt F.

    1998-01-01

    Presents a case study focusing on the mill-supported Lindale Band in Lindale, Georgia in order to examine the influences of industry on instrumental music education in the U.S. South. Investigates the history of U.S. industrial bands and the philosophical parallels between industry and progressive education. (CMK)

  7. Band-notched ultrawide band antenna loaded with ferrite slab

    Science.gov (United States)

    Wang, Hao; Zong, Weihua; Sun, Nian X.; Lin, Hwaider; Li, Shandong

    2017-05-01

    In this paper, a novel technique to design a band-notched UWB antenna by using Yttrium Iron Garnet (YIG) ferrite is proposed. A printed slot UWB antenna with size of 21mm×26 mm×0.8 mm is adopted as a basic antenna. A piece of ferrite slab with size of 5 mm×10 mm×2 mm is attached on the feeding layer of the antenna to achieve band-notched characteristics. The measured -10 dB bandwidth of the antenna without ferrite slab is 2.91-10.98 GHz. With loading of ferrite slab, the bandwidth turns to 2.73-5.12 and 5.87-10.78 GHz. A band notch of 5.12- 5.87 GHz is achieved to filter WLAN 5 GHz (5.15-5.825 GHz) band. The proposed technique has virtue of easy fabrication and keeping antenna miniaturization.

  8. A new wideband negative refractive index metamaterial for dual-band operation

    Science.gov (United States)

    Islam, S. S.; Faruque, M. R. I.; Islam, M. T.; Ali, M. T.

    2017-04-01

    A new wideband negative refractive index (NRI) metamaterial for dual-band operation is introduced in this study. Initially, a bare-H-shaped resonator was designed over the FR-4 substrate material. The refractive index curve for the unit cell, displays more than 3-GHz negative real peak from C-band to some portion of X-band. The proposed design also displays NRI property in the same frequency bands with wider bandwidth, when the Rogers RT 3010 substrate material was employed instead of FR-4 substrate material.

  9. Band-to-Band Tunneling Transistors: Scalability and Circuit Performance

    Science.gov (United States)

    2013-05-01

    55* MEDICI ...3.2.1 Tunneling Theory 3.3 Simulation Methods 3.3.1 MEDICI 3.3.2 Sentaurus Local Tunneling 3.3.3 Sentaurus Nonlocal Tunneling 3.4 Sentaurus...tunneling current. 3.3.1 MEDICI MEDICI is a one and two-dimensional simulator created by Synopsys, Inc. [18]. It contains a band-to-band

  10. Progressivity Enhanced

    Directory of Open Access Journals (Sweden)

    Marko Hren

    2013-09-01

    Full Text Available Rather than a scientific text, the author contributes a concise memorandum from the originator of the idea who has managed the campaign for the conversion of the military barracks into a creative cluster between 1988 and 2002, when he parted ways with Metelkova due to conflicting views on the center’s future. His views shed light on a distant period of time from a perspective of a participant–observer. The information is abundantly supported by primary sources, also available online. However, some of the presented hypotheses are heavily influenced by his personal experiences of xenophobia, elitism, and predatorial behavior, which were already then discernible on the so-called alternative scene as well – so much so that they obstructed the implementation of progressive programs. The author claims that, in spite of the substantially different reality today, the myths and prejudices concerning Metelkova must be done away with in order to enhance its progressive nature. Above all, the paper calls for an objective view on internal antagonisms, mainly originating in deep class divisions between the users. These make a clear distinction between truly marginal ndividuals and the overambitious beau-bourgeois, as the author labels the large part of users of Metelkova of »his« time. On these grounds, he argues for a robust approach to ban all forms of xenophobia and self-ghettoization.

  11. Chemically induced compaction bands in geomaterials

    Science.gov (United States)

    Stefanou, Ioannis; Sulem, Jean

    2013-04-01

    Compaction bands play an important role in oil production and may provide useful information on various geological processes. Various mechanisms can be involved at different scales: the micro scale (e.g. the grain scale), the meso scale (e.g. the Representative Element Volume) and the macro scale (e.g. the structure). Moreover, hydro-chemo-mechanical couplings might play an important role in triggering instabilities in the form of compaction bands. Compaction bands can be seen as an instability of the underneath mathematical problem leading to localization of deformation [1,2,3]. Here we explore the conditions of compaction banding in quartz-based geomaterials by considering the effect of chemical dissolution and precipitation [4,5]. In due course of the loading process grain crushing affects the residual strength, the porosity and the permeability of the material. Moreover, at the micro-level, grain crushing results in an increase of the grain specific surface, which accelerates the dissolution [6]. Consequently, the silica is removed more rapidly from the grain skeleton and the overall mechanical properties are degraded due to chemical factors. The proposed model accounts for these phenomena. In particular, the diffusion of the diluted in the water silica is considered through the mass balance equation of the porous medium. The reduction of the mechanical strength of the material is described through a macroscopic failure criterion with chemical softening. The grain size reduction is related to the total energy input [7]. A grain size and porosity dependent permeability law is adopted. These degradation mechanisms are coupled with the dissolution/precipitation reaction kinetics. The obtained hydro-chemo-mechanical model is used to investigate the conditions, the material parameters and the chemical factors inducing compaction bands formation. References [1] J.W. Rudnicki, and J.R. Rice. "Conditions for the Localization of Deformation in Pressure

  12. GaN and ZnO-based materials and devices

    CERN Document Server

    2012-01-01

    The AlInGaN and ZnO materials systems have proven to be one of the scientifically and technologically important areas of development over the past 15 years, with applications in UV/visible optoelectronics and in high-power/high-frequency microwave devices. The pace of advances in these areas has been remarkable and the wide band gap community relies on books like the one we are proposing to provide a review and summary of recent progress.

  13. Progress report

    International Nuclear Information System (INIS)

    Brumovsky, M.

    1979-01-01

    Progress Report, covering the period up to the end of 1979 year, was sent to the IAEA according to the research agreement No. 1971 /CF. This work covered the following fields: preparation and dummy irradiation experiments with a new experimental capsule of ''CHOUCA-M'' type; measurement of temperature fields and design of specimen holders; measurement of neutron energy spectrum in the irradiation place in our experimental reactor of VVR-S type (Nuclear Research Institute) using a set of activation detectors; unification and calibration of the measurement of neutron fluence with the use of Fe, Cu, Mn-Mg and Co-Al monitors; development and improvement of the measuring apparatus and technique for the dynamic testing of pre-cracked specimens with determination of dynamic parameters of fracture mechanics; preparation and manufacture of testing specimens from the Japanese steels - forging, plate and weld metal; preparation of the irradiation capsule for assembling

  14. Intensity formulas for triplet bands

    Science.gov (United States)

    Budo, A.

    1982-01-01

    Previous work in this area is surveyed and the mathematics involved in determining the quantitative intensity measurements in triplet bands is presented. Explicit expressions for the intensity distribution in the branches of the 3 Sigma-3 Pi and 1 Sigma-3Pi bands valid for all values of the coupling constant Y of the 3 Pi terms are given. The intensity distribution calculated according to the formulas given is compared with measurements of PH, 3 Pi-3 Sigma. Good quantitative agreement is obtained.

  15. Topological magnon bands in ferromagnetic star lattice

    Science.gov (United States)

    Owerre, S. A.

    2017-05-01

    The experimental observation of topological magnon bands and thermal Hall effect in a kagomé lattice ferromagnet Cu(1-3, bdc) has inspired the search for topological magnon effects in various insulating ferromagnets that lack an inversion center allowing a Dzyaloshinskii-Moriya (DM) spin-orbit interaction. The star lattice (also known as the decorated honeycomb lattice) ferromagnet is an ideal candidate for this purpose because it is a variant of the kagomé lattice with additional links that connect the up-pointing and down-pointing triangles. This gives rise to twice the unit cell of the kagomé lattice, and hence more interesting topological magnon effects. In particular, the triangular bridges on the star lattice can be coupled either ferromagnetically or antiferromagnetically which is not possible on the kagomé lattice ferromagnets. Here, we study DM-induced topological magnon bands, chiral edge modes, and thermal magnon Hall effect on the star lattice ferromagnet in different parameter regimes. The star lattice can also be visualized as the parent material from which topological magnon bands can be realized for the kagomé and honeycomb lattices in some limiting cases.

  16. Building blocks of topological quantum chemistry: Elementary band representations

    Science.gov (United States)

    Cano, Jennifer; Bradlyn, Barry; Wang, Zhijun; Elcoro, L.; Vergniory, M. G.; Felser, C.; Aroyo, M. I.; Bernevig, B. Andrei

    2018-01-01

    The link between chemical orbitals described by local degrees of freedom and band theory, which is defined in momentum space, was proposed by Zak several decades ago for spinless systems with and without time reversal in his theory of "elementary" band representations. In a recent paper [Bradlyn et al., Nature (London) 547, 298 (2017), 10.1038/nature23268] we introduced the generalization of this theory to the experimentally relevant situation of spin-orbit coupled systems with time-reversal symmetry and proved that all bands that do not transform as band representations are topological. Here we give the full details of this construction. We prove that elementary band representations are either connected as bands in the Brillouin zone and are described by localized Wannier orbitals respecting the symmetries of the lattice (including time reversal when applicable), or, if disconnected, describe topological insulators. We then show how to generate a band representation from a particular Wyckoff position and determine which Wyckoff positions generate elementary band representations for all space groups. This theory applies to spinful and spinless systems, in all dimensions, with and without time reversal. We introduce a homotopic notion of equivalence and show that it results in a finer classification of topological phases than approaches based only on the symmetry of wave functions at special points in the Brillouin zone. Utilizing a mapping of the band connectivity into a graph theory problem, we show in companion papers which Wyckoff positions can generate disconnected elementary band representations, furnishing a natural avenue for a systematic materials search.

  17. Second version of France's National Radioactive Materials and Waste Management Plan: an ambitious road-map for progress on sustainable radioactive materials and waste management; Seconde edition du Plan national de gestion des matieres et des dechets radioactifs: ue feuille de route ambitieuse pour progresser dans la gestion durable des matieres et des dechets radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Clemente, C. [Autorite de Surete Nucleaire, adjointe au directeur du transport et des sources, 75 - Paris (France)

    2011-02-15

    France's National Radioactive Materials and Waste Management Plan (PNGMDR) aims at drawing up regular reviews of application of the management policy regarding radioactive substances, according to a framework defined by Law. It is drawn up by a multidisciplinary work-group, chaired by the Directorate-General for Energy and Climate (DGEC) and the French Nuclear Safety Authority (ASN). The Plan is updated every three years and the second version was finalized at the end of 2009. The PNGMDR Plan is intended to be exhaustive. It embraces radioactive waste, reusable radioactive materials, sealed sources, technologically-enhanced naturally-occurring radioactive waste, as well as mining residue and spoil. It presents existing storage and disposal solutions and identifies needs for storage or disposal based on the national inventory of radioactive materials and waste, together with the facilities that need to be developed. The studies carried out under the PNGMDR must also ensure that waste management within each of these channels is optimised. Lastly, the Plan sets research and studies objectives, especially as related to waste for which there is as yet no disposal channel. The main recommendations contained in the Plan, together with milestones and deadlines related to radioactive materials and waste management are taken up in French regulations via provisions set out in a decree and an order stipulating the applicable requirements. (author)

  18. Multiple sclerosis presenting with progressive visual failure.

    OpenAIRE

    Ormerod, I E; McDonald, W I

    1984-01-01

    Progressive visual failure as the presenting feature of multiple sclerosis is described in five patients. The clinical features did not permit a distinction from visual loss due to compression. The finding of oligoclonal bands in the CSF at presentation is a useful pointer to the diagnosis, but is not specific and full investigation to exclude treatable causes of visual loss is essential.

  19. Progress report, Chemistry and Materials Division

    International Nuclear Information System (INIS)

    1982-02-01

    A marked asymmetry has been observed in the intensity of ions scattered from manganese atoms in a Mn-Al alloy as a function of incidence angle, under near-axial channeling conditions. Proton dechanneling has been used to discriminate between simple and cluster defects created by He-ion irradiation of an Al-Ag alloy crystal. An automated Langmuir surface has been constructed for study of the radiation chemistry of polyunsaturated compounds organized in molecular films. New information about reactions of nitric oxide (NO) has been obtained which suggests that the reaction of NO with O 2 in the gas phase is also an important reaction in the radiation chemistry of oxygenated nitrate and nitrite solutions. Development work on an ion-selective electrode for the determination of boron has been completed. Recent studies have resulted in improvements to the mass spectrometric determination of thorium, uranium and plutonium. Good agreement between the results of the determinations of atom percent fission by a stable isotope dilution Nd-148 and a uranium isotope ratio method was observed. Examination of a large number of iodine-induced crack initiation sites formed under conditions where the hydrides are in solution has shown no evidence for the involvement of any second phase particles, or any local segregation of impurities or alloying elements. Reproducible improvement in the purity of zirconium has been achieved by the electrotransport method. Doppler broadening studies of positron annihilation in electron irradiated Zr and Ti have been completed

  20. Progress report, Chemistry and Materials Division

    International Nuclear Information System (INIS)

    1980-11-01

    New results have been obtained by time-of-flight studies for the stopping powers for heavy ions (Ne,Ar) transmitted at O 0 through tin, copper and gold foils. It has been shown that complexes formed between vacancies and solute ions can be dissolved by MeV He + ion irradiation at 70 K. An improved optical absorption spectrum of hypoiodite ion has been obtained. Studies of the radiolysis of gadolinium solutions covered with a vapour space are continuing. Research on hydrogen isotope separation by laser photochemistry and catalytic chemical exchange is going forward. A method for the determination of trace quantities of hexavalent uranium in groundwater and urine has been found. Preliminary experiments have been carried out on zone refining and electrotransport purification of zirconium. Irradiation creep and growth are bieng examined, and an experimental study of recovery in Zircaloy-2 from mechanical deformation has been completed. (LL)