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Sample records for solid-state thermal reaction

  1. Kinetic concepts of thermally stimulated reactions in solids

    Science.gov (United States)

    Vyazovkin, Sergey

    Historical analysis suggests that the basic kinetic concepts of reactions in solids were inherited from homogeneous kinetics. These concepts rest upon the assumption of a single-step reaction that disagrees with the multiple-step nature of solid-state processes. The inadequate concepts inspire such unjustified anticipations of kinetic analysis as evaluating constant activation energy and/or deriving a single-step reaction mechanism for the overall process. A more adequate concept is that of the effective activation energy, which may vary with temperature and extent of conversion. The adequacy of this concept is illustrated by literature data as well as by experimental data on the thermal dehydration of calcium oxalate monohydrate and thermal decomposition of calcium carbonate, ammonium nitrate and 1,3,5,7- tetranitro-1,3,5,7-tetrazocine.

  2. Solid state reaction in alumina nanoparticles/LZSA glass-ceramic composites

    International Nuclear Information System (INIS)

    Montedo, O.K.; Oliveira, A.N. de; Raupp-Pereira, F.

    2016-01-01

    Full text: The aim of this work is to present results related to solid state reactions on LZSA glass-ceramic composites containing alumina reinforcement nano-particles. A LZSA (Li2O-ZrO2-SiO2-Al2O3) glass-ceramic has been prepared by sintering of powders and characterized. Composites containing 0 to 77 vol.% of alumina nanoparticles (27-43 nm APS, 35 m2.g-1 SSA) and a 16.9Li2O•5.0ZrO2•65.1SiO2•8.6Al2O3 glass-ceramic matrix have been prepared. X-ray diffractometry studies have been performed in order of investigating the solid state reactions occurring in LZSA-based composites. Results of the XRD patterns have been related to the coefficient of thermal expansion (CTE), Young modulus, and dielectric constant, showing that, in comparison with the glass-ceramic composition, the composites showed a decrease of CTE with the alumina concentration increasing, due to the increasing of beta-spodumeness formation (solid solution of beta-spodumene, Li2O.Al2O3.4-10SiO2). The performance of the glass-ceramic was improved with the alumina nano-particles addition, showing potential of using in the preparation of Low Thermal Co-fired Ceramics (LTCC). (author)

  3. Nanocrystalline spinel ferrites by solid state reaction route

    Indian Academy of Sciences (India)

    Wintec

    Nanocrystalline spinel ferrites by solid state reaction route. T K KUNDU* and S MISHRA. Department of Physics, Visva-Bharati, Santiniketan 731 235, India. Abstract. Nanostructured NiFe2O4, MnFe2O4 and (NiZn)Fe2O4 were synthesized by aliovalent ion doping using conventional solid-state reaction route. With the ...

  4. Solid-state polymerisation via [2+2] cycloaddition reaction involving coordination polymers.

    Science.gov (United States)

    Medishetty, Raghavender; Park, In-Hyeok; Lee, Shim Sung; Vittal, Jagadese J

    2016-03-14

    Highly crystalline metal ions containing organic polymers are potentially useful to manipulate the magnetic and optical properties to make advanced multifunctional materials. However, it is challenging to synthesise monocrystalline metal complexes of organic polymers and single-phase hybrid materials made up of both coordination and organic polymers by traditional solution crystallisation. This requires an entirely different approach in the solid-state by thermal or photo polymerisation of the ligands. Among the photochemical methods available, [2+2] cycloaddition reaction has been recently employed to generate cyclobutane based coordination polymers from the metal complexes. Cyclobutane polymers have also been integrated into coordination polymers in this way. Recent advancements in the construction of polymeric chains of cyclobutane rings through photo-dimerisation reaction in the monocrystalline solids containing metal complexes, coordination polymers and metal-organic framework structures are discussed here.

  5. Ambient Mechanochemical Solid-State Reactions of Carbon Nanotubes and Their Reactions via Covalent Coordinate Bond in Solution

    Science.gov (United States)

    Kabbani, Mohamad A.

    In its first part, this thesis deals with ambient mechanochemical solid-state reactions of differently functionalized multiple walled carbon nanotubes (MWCNTs) while in its second part it investigates the cross-linking reactions of CNTs in solution via covalent coordinate bonds with transitions metals and carboxylate groups decorating their surfaces. In the first part a series of mechanochemical reactions involving different reactive functionalities on the CNTs such as COOH/OH, COOH/NH2 and COCl/OH were performed. The solid-state unzipping of CNTs leading to graphene formation was confirmed using spectroscopic, thermal and electron microscopy techniques. The non-grapheme products were established using in-situ quadruple mass spectroscopy. The experimental results were confirmed by theoretical simulation calculations using the 'hot spots' protocol. The kinetics of the reaction between MWCNT-COOH and MWCNT-OH was monitored using variable temperature Raman spectroscopy. The low activation energy was discussed in terms of hydrogen bond mediated proton transfer mechanism. The second part involves the reaction of MWCNTII COOH with Zn (II) and Cu (II) to form CNT metal-organic frame (MOFs) products that were tested for their effective use as counter-electrodes in dyes sensitized solar cells (DSSC). The thesis concludes by the study of the room temperature reaction between the functionalized graphenes, GOH and G'-COOH followed by the application of compressive loads. The 3D solid graphene pellet product ( 0.6gm/cc) is conductive and reflective with a 35MPa ultimate strength as compared to 10MPa strength of graphite electrode ( 2.2gm/cc).

  6. The effect of interfaces on solid-state reactions between oxides

    International Nuclear Information System (INIS)

    Johnson, M.T.; Carter, C.B.

    1998-01-01

    A thin-film geometry has been used to study fundamental solid-state reaction processes occurring at interfaces in two spinel-forming oxide systems. In the first system, NiO/Al 2 O 3 , epitactic NiO films were deposited on various orientations of single-crystal α-Al 2 O 3 . In this case, the reaction kinetics were studied and correlated with the interfacial structure (or substrate orientation). In the second, In 2 O 3 /MgO, solid-state reactions were studied under the influence of an electric field. The electric field provides a driving force for mass transport that affects both the reaction process and the morphological stability of an interface

  7. Thermal management of solid state lighting module

    NARCIS (Netherlands)

    Ye, H.

    2014-01-01

    Solid-State Lighting (SSL), powered by Light-Emitting Diodes (LEDs), is an energy-efficient technology for lighting systems. In contrast to incandescent lights which obtain high efficiency at high temperatures, the highest efficiency of LEDs is reached at low temperatures. The thermal management in

  8. Ion-beam mixing and solid-state reaction in Zr-Fe multilayers

    International Nuclear Information System (INIS)

    Paesano, A. Jr.; Motta, A.T.; Birtcher, R.C.; Ryan, E.A.; Teixeira, S.R.; Bruckmann, M.E.; Amaral, L.

    1997-01-01

    Vapor-deposited Zr-Fe multilayered thin films with various wavelengths and of overall composition either 50% Fe or Fe-rich up to 57% Fe were either irradiated with 300 keV Kr ions at temperatures from 25 K to 623 K to fluences up to 2 x 10 16 cm -2 , or simply annealed at 773 K in-situ in the Intermediate Voltage Electron microscope At Argonne National Laboratory. Under irradiation, the final reaction product is the amorphous phase in all cases studied, but the dose to amorphization depends on the temperature and on the wavelength. In the purely thermal case (annealing at 773 K), the 50-50 composition produces the amorphous phase but for the Fe-rich multilayers the reaction products depend on the multilayer wavelength. For small wavelength, the amorphous phase is still formed, but at large wavelength the Zr-Fe crystalline intermetallic compounds appear. These results are discussed in terms of existing models of irradiation kinetics and phase selection during solid state reaction

  9. Synthesis of Cubic Phase-Co Microspheres by Mechanical Solid-State Reaction-Thermal Decomposition and Research on Its Growth Kinetics

    Directory of Open Access Journals (Sweden)

    Ying Deng

    2016-01-01

    Full Text Available Cubic phase cobalt (Co, which can be used as a key component for composite materials given its excellent ductility and internal structure, is not easy to obtain at room temperature. In this study, oxalic acid and cobalt nitrate are used as raw materials to synthesize the cobalt oxalate precursor, which has a stable structure with a five-membered chelate ring. Cobalt oxalate microspheres, having a high internal energy content, were prepared by using mechanical solid-state reaction in the presence of a surfactant, which can produce spherical micelles. The thermal decomposition of the precursor was carried out by maintaining it in a nitrogen atmosphere at 450°C for 3 h. At the end of the procedure, 100 nm cubic phase-Co microspheres, stable at room temperature, were obtained. Isothermal and nonisothermal kinetic mechanisms of cobalt grain growth were investigated. The cubic-Co grain growth activation energy, Q, was calculated in this study to be 71.47 kJ/mol. The required reaction temperature was low, making the production process simple and suitable for industrial applications.

  10. Molecularly Engineered Azobenzene Derivatives for High Energy Density Solid-State Solar Thermal Fuels.

    Science.gov (United States)

    Cho, Eugene N; Zhitomirsky, David; Han, Grace G D; Liu, Yun; Grossman, Jeffrey C

    2017-03-15

    Solar thermal fuels (STFs) harvest and store solar energy in a closed cycle system through conformational change of molecules and can release the energy in the form of heat on demand. With the aim of developing tunable and optimized STFs for solid-state applications, we designed three azobenzene derivatives functionalized with bulky aromatic groups (phenyl, biphenyl, and tert-butyl phenyl groups). In contrast to pristine azobenzene, which crystallizes and makes nonuniform films, the bulky azobenzene derivatives formed uniform amorphous films that can be charged and discharged with light and heat for many cycles. Thermal stability of the films, a critical metric for thermally triggerable STFs, was greatly increased by the bulky functionalization (up to 180 °C), and we were able to achieve record high energy density of 135 J/g for solid-state STFs, over a 30% improvement compared to previous solid-state reports. Furthermore, the chargeability in the solid state was improved, up to 80% charged from 40% charged in previous solid-state reports. Our results point toward molecular engineering as an effective method to increase energy storage in STFs, improve chargeability, and improve the thermal stability of the thin film.

  11. Solid state phase change materials for thermal energy storage in passive solar heated buildings

    Science.gov (United States)

    Benson, D. K.; Christensen, C.

    1983-11-01

    A set of solid state phase change materials was evaluated for possible use in passive solar thermal energy storage systems. The most promising materials are organic solid solutions of pentaerythritol, pentaglycerine and neopentyl glycol. Solid solution mixtures of these compounds can be tailored so that they exhibit solid-to-solid phase transformations at any desired temperature within the range from less than 25 deg to 188 deg. Thermophysical properties such as thermal conductivity, density and volumetric expansion were measured. Computer simulations were used to predict the performance of various Trombe wall designs incorporating solid state phase change materials. Optimum performance was found to be sensitive to the choice of phase change temperatures and to the thermal conductivity of the phase change material. A molecular mechanism of the solid state phase transition is proposed and supported by infrared spectroscopic evidence.

  12. Microscale solid-state thermal diodes enabling ambient temperature thermal circuits for energy applications

    KAUST Repository

    Wang, Song

    2017-05-10

    Thermal diodes, or devices that transport thermal energy asymmetrically, analogous to electrical diodes, hold promise for thermal energy harvesting and conservation, as well as for phononics or information processing. The junction of a phase change material and phase invariant material can form a thermal diode; however, there are limited constituent materials available for a given target temperature, particularly near ambient. In this work, we demonstrate that a micro and nanoporous polystyrene foam can house a paraffin-based phase change material, fused to PMMA, to produce mechanically robust, solid-state thermal diodes capable of ambient operation with Young\\'s moduli larger than 11.5 MPa and 55.2 MPa above and below the melting transition point, respectively. Moreover, the composites show significant changes in thermal conductivity above and below the melting point of the constituent paraffin and rectification that is well-described by our previous theory and the Maxwell–Eucken model. Maximum thermal rectifications range from 1.18 to 1.34. We show that such devices perform reliably enough to operate in thermal diode bridges, dynamic thermal circuits capable of transforming oscillating temperature inputs into single polarity temperature differences – analogous to an electrical diode bridge with widespread implications for transient thermal energy harvesting and conservation. Overall, our approach yields mechanically robust, solid-state thermal diodes capable of engineering design from a mathematical model of phase change and thermal transport, with implications for energy harvesting.

  13. Thermal reactions of some calcium, strontium, and barium chromates

    International Nuclear Information System (INIS)

    Piekarska-Piesse, B.; Gontarz, Z.; Ostrowski, A.; Kucharski, R.

    2000-01-01

    Thermal decomposition of calcium chromates and solid state reactions of barium and strontium chromates(VI) with barium and strontium hydroxides and carbonates, as well as the reduction of chromates by carbon and hydrogen, have been investigated. The mechanisms of individual stages of the thermal decomposition have been proposed on the basis of morphological classification. (author)

  14. Rapid Thermal Annealing of Cathode-Garnet Interface toward High-Temperature Solid State Batteries.

    Science.gov (United States)

    Liu, Boyang; Fu, Kun; Gong, Yunhui; Yang, Chunpeng; Yao, Yonggang; Wang, Yanbin; Wang, Chengwei; Kuang, Yudi; Pastel, Glenn; Xie, Hua; Wachsman, Eric D; Hu, Liangbing

    2017-08-09

    High-temperature batteries require the battery components to be thermally stable and function properly at high temperatures. Conventional batteries have high-temperature safety issues such as thermal runaway, which are mainly attributed to the properties of liquid organic electrolytes such as low boiling points and high flammability. In this work, we demonstrate a truly all-solid-state high-temperature battery using a thermally stable garnet solid-state electrolyte, a lithium metal anode, and a V 2 O 5 cathode, which can operate well at 100 °C. To address the high interfacial resistance between the solid electrolyte and cathode, a rapid thermal annealing method was developed to melt the cathode and form a continuous contact. The resulting interfacial resistance of the solid electrolyte and V 2 O 5 cathode was significantly decreased from 2.5 × 10 4 to 71 Ω·cm 2 at room temperature and from 170 to 31 Ω·cm 2 at 100 °C. Additionally, the diffusion resistance in the V 2 O 5 cathode significantly decreased as well. The demonstrated high-temperature solid-state full cell has an interfacial resistance of 45 Ω·cm 2 and 97% Coulombic efficiency cycling at 100 °C. This work provides a strategy to develop high-temperature all-solid-state batteries using garnet solid electrolytes and successfully addresses the high contact resistance between the V 2 O 5 cathode and garnet solid electrolyte without compromising battery safety or performance.

  15. Reaction diffusion and solid state chemical kinetics handbook

    CERN Document Server

    Dybkov, V I

    2010-01-01

    This monograph deals with a physico-chemical approach to the problem of the solid-state growth of chemical compound layers and reaction-diffusion in binary heterogeneous systems formed by two solids; as well as a solid with a liquid or a gas. It is explained why the number of compound layers growing at the interface between the original phases is usually much lower than the number of chemical compounds in the phase diagram of a given binary system. For example, of the eight intermetallic compounds which exist in the aluminium-zirconium binary system, only ZrAl3 was found to grow as a separate

  16. High power solid state retrofit lamp thermal characterization and modeling

    NARCIS (Netherlands)

    Jakovenko, J.; Formánek, J.; Vladimír, J.; Husák, M.; Werkhoven, R.J.

    2012-01-01

    Thermal and thermo-mechanical modeling and characterization of solid state lightening (SSL) retrofit LED Lamp are presented in this paper. Paramount Importance is to design SSL lamps for reliability, in which thermal and thermo-mechanical aspects are key points. The main goal is to get a precise 3D

  17. Study of Ni/Si(1 0 0) solid-state reaction with Al addition

    International Nuclear Information System (INIS)

    Huang Yifei; Jiang Yulong; Ru Guoping; Li Bingzong

    2008-01-01

    The characteristics of Ni/Si(1 0 0) solid-state reaction with Al addition (Ni/Al/Si(1 0 0), Ni/Al/Ni/Si(1 0 0) and Al/Ni/Si(1 0 0)) is studied. Ni and Al films were deposited on Si(1 0 0) substrate by ion beam sputtering. The solid-state reaction between metal films and Si was performed by rapid thermal annealing. The sheet resistance of the formed silicide film was measured by four-point probe method. The X-ray diffraction (XRD) was employed to detect the phases in the silicide film. The Auger electron spectroscopy was applied to reveal the element profiles in depth. The influence of Al addition on the Schottky barrier heights of the formed silicide/Si diodes was investigated by current-voltage measurements. The experimental results show that NiSi forms even with the addition of Al, although the formation temperature correspondingly changes. It is revealed that Ni silicidation is accompanied with Al diffusion in Ni film toward the film top surface and Al is the dominant diffusion species in Ni/Al system. However, no Ni x Al y phase is detected in the films and no significant Schottky barrier height modulation by the addition of Al is observed

  18. Studies of ruthenium complexes, 8. Kinetic studies of the thermal substitution reaction of hexaammine and cis--dihalogenotetraammineruthenium(III) complexes in the solid state

    Energy Technology Data Exchange (ETDEWEB)

    Ohyoshi, A; Hiraki, S; Odate, T; Kohata, S; Oda, J [Kumamoto Univ. (Japan). Faculty of Engineering

    1975-01-01

    The kinetics of the thermal substitution reaction of hexaamineruthenium (III) halides and cis-dihalogenotetraamineruthenium (III) halides have been studied in the solid state. The reaction rates and kinetic parameters were determined for these two reactions; (Ru(NH/sub 3/)/sub 6/)X/sub 3/..-->..(RuX(NH/sub 3/)/sub 5/)X/sub 2/+NH/sub 3/, (X=Br, I) and cis - (RuX/sub 2/(NH/sub 3/)/sub 4/)X..-->..(RuX/sub 3/(NH/sub 3/)/sub 3/)+NH/sub 3/, (X=Cl, Br). The values of the rate constant, the activation energy, and the activation entropy were 2.10x10/sup -5/ s/sup -1/ (at 161/sup 0/C), 23.2 kcal mol/sup -1/, and -29.3 e.u. for the hexaamine bromide, and 2.92x10/sup -5/ s/sup -1/ (at 162/sup 0/C), 31.3 kcal mol/sup -1/, and -10.1 e.u. for the cis-dibromotetraamine bromide. The Ssub(N)2 mechanism is more probable for the former reaction, while the Ssub(N)1 mechanism is more probable for the latter reaction.

  19. Physicochemical properties and thermal stability of quercetin hydrates in the solid state

    Energy Technology Data Exchange (ETDEWEB)

    Borghetti, G.S., E-mail: greicefarm@yahoo.com.br [Programa de Pos-Graduacao em Ciencias Farmaceuticas, Faculdade de Farmacia, Universidade Federal do Rio Grande do Sul, Av. Ipiranga 2752, CEP 90.610-000, Porto Alegre, RS (Brazil); Carini, J.P. [Programa de Pos-Graduacao em Ciencias Farmaceuticas, Faculdade de Farmacia, Universidade Federal do Rio Grande do Sul, Av. Ipiranga 2752, CEP 90.610-000, Porto Alegre, RS (Brazil); Honorato, S.B.; Ayala, A.P. [Departamento de Fisica, Universidade Federal do Ceara, Caixa Postal 6030, CEP 60.455-970, Fortaleza, CE (Brazil); Moreira, J.C.F. [Departamento de Bioquimica, Instituto de Ciencias Basicas da Saude, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600, CEP 90035-003, Porto Alegre, RS (Brazil); Bassani, V.L. [Programa de Pos-Graduacao em Ciencias Farmaceuticas, Faculdade de Farmacia, Universidade Federal do Rio Grande do Sul, Av. Ipiranga 2752, CEP 90.610-000, Porto Alegre, RS (Brazil)

    2012-07-10

    Highlights: Black-Right-Pointing-Pointer Quercetin raw materials may present different degree of hydration. Black-Right-Pointing-Pointer Thermal stability of quercetin in the solid state depends on its degree of hydration. Black-Right-Pointing-Pointer Quercetin dehydrate is thermodynamically more stable than the other crystal forms. - Abstract: In the present work three samples of quercetin raw materials (QCTa, QCTb and QCTc), purchased from different Brazilian suppliers, were characterized employing scanning electron microscopy, Raman spectroscopy, simultaneous thermogravimetry and infrared spectroscopy, differential scanning calorimetry, and variable temperature-powder X-ray diffraction, in order to know their physicochemical properties, specially the thermal stability in solid state. The results demonstrated that the raw materials of quercetin analyzed present distinct crystalline structures, ascribed to the different degree of hydration of their crystal lattice. The thermal stability of these quercetin raw materials in the solid state was highly dependent on their degree of hydration, where QCTa (quercetin dihydrate) was thermodynamically more stable than the other two samples.

  20. Solid state polymerization: its action on thermal and rheological properties of PET/PC reactive blends

    Directory of Open Access Journals (Sweden)

    Luis C. Mendes

    2013-01-01

    Full Text Available The solid state polymerization (SSP of PET/PC reactive extrusion blends - with and without cobalt catalyst - at different polymer ratios was studied. Thermal and rheological evaluations were performed. DSC results showed changes in the PET's Tg, Tch, Tm and Xc.. The melt flow rate (MFR decreased for PET and the blends. The intrinsic viscosity increased. The variation in calorimetric and rheological properties might be attributed to the PET's chain extension reactions - esterification and transesterification. These reactions led to an increase in the PET's molar mass, consequently shifting the PET's Tg to lower temperature and PET's crystallization, besides reducing the blend miscibility and flowability.

  1. Thermal theory of autowave processes in low-temperature solid-phase radiochemical reactions

    International Nuclear Information System (INIS)

    Barelko, V.V.; Barkalov, I.M.; Vaganov, D.A.; Zanin, A.M.; Kiryukhin, D.P.

    1982-01-01

    A new phenomenon in radiation cryochemistry concerning the class of autowave processes was previously discovered. It was observed in halogenation and hydrohalogenation of hydrocarbons and consisted of spontaneous, laminar propagation of a chemical transformation wave based on a frozen mixture of reagents previously irradiated with 60 Co γ-rays. The effect of the positive inverse correlation between the chemical conversion and brittle fracture of a solid sample of reagents is the phenomenological basis of the phenomenon; formation of fractures triggers a reactive process which takes place on their active surface (or in the layer adjacent to it), and the chemical reaction, in turn, stimulates the subsequent development of the process of decomposition. As a result, a single brittle fracture and chemical conversion wave which moves along the solid sample arises. Different mechanisms of generation of fracture surfaces under the effect of the reaction are possible. A difference in the densities of the initial reagents and the products of the reaction could be one of the causes of brittle fracture, and the thermal stresses induced by the exothermicity of the chemical processes could be another cause. The present work concerns the analysis of the features of the wave process which occurs based on the second, thermal mechanism. The analysis was conducted within the framework of a phenomenological approach which does not require specific definition of the nature of the chemical activation of the system during its brittle fracture

  2. Chemical degradation of proteins in the solid state with a focus on photochemical reactions.

    Science.gov (United States)

    Mozziconacci, Olivier; Schöneich, Christian

    2015-10-01

    Protein pharmaceuticals comprise an increasing fraction of marketed products but the limited solution stability of proteins requires considerable research effort to prepare stable formulations. An alternative is solid formulation, as proteins in the solid state are thermodynamically less susceptible to degradation. Nevertheless, within the time of storage a large panel of kinetically controlled degradation reactions can occur such as, e.g., hydrolysis reactions, the formation of diketopiperazine, condensation and aggregation reactions. These mechanisms of degradation in protein solids are relatively well covered by the literature. Considerably less is known about oxidative and photochemical reactions of solid proteins. This review will provide an overview over photolytic and non-photolytic degradation reactions, and specially emphasize mechanistic details on how solid structure may affect the interaction of protein solids with light. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. An alternative preparation method for ion exchanged catalysts: Solid state redox reaction

    DEFF Research Database (Denmark)

    Schneider, E.; Hagen, A.; Grunwaldt, J.-D.

    2004-01-01

    A new method for modifying zeolites with zinc is proposed. The solid state redox reaction between metallic zinc and ZSM-5 zeolites with different Si/Al ratios was investigated by temperature programmed hydrogen evolution (TPHE), X-ray absorption near edge structure (XANES) and diffuse reflectance...... infrared Fourier transform spectroscopy (DRIFTS). The evolution of hydrogen was detected at temperatures above 620 K. The source of hydrogen was the solid state redox reaction of the metal with protons of the support. The samples exhibit catalytic activity in ethane aromatization indicating that zinc...... should be located at the same sites as in catalysts prepared by conventional methods. Combination of XANES and catalytic activity point to zinc being mainly present in tetrahedral geometry under reaction conditions....

  4. Analysis of structural and thermal stability in the positive electrode for sulfide-based all-solid-state lithium batteries

    Science.gov (United States)

    Tsukasaki, Hirofumi; Otoyama, Misae; Mori, Yota; Mori, Shigeo; Morimoto, Hideyuki; Hayashi, Akitoshi; Tatsumisago, Masahiro

    2017-11-01

    Sulfide-based all-solid-state batteries using a non-flammable inorganic solid electrolyte are promising candidates as a next-generation power source owing to their safety and excellent charge-discharge cycle characteristics. In this study, we thus focus on the positive electrode and investigated structural stabilities of the interface between the positive electrode active material LiNi1/3Mn1/3Co1/3O2 (NMC) and the 75Li2S·25P2S5 (LPS) glass electrolyte after charge-discharge cycles via transmission electron microscopy (TEM). To evaluate the thermal stability of the fabricated all-solid-state cell, in-situ TEM observations for the positive electrode during heating are conducted. As a result, structural and morphological changes are detected in the LPS glasses. Thus, exothermal reaction present in the NMC-LPS composite positive electrode after the initial charging is attributable to the crystallization of LPS glasses. On the basis of a comparison with crystallization behavior in single LPS glasses, the origin of exothermal reaction in the NMC-LPS composites is discussed.

  5. Achieving dynamic behaviour and thermal expansion in the organic solid state via co-crystallization.

    Science.gov (United States)

    Hutchins, Kristin M; Groeneman, Ryan H; Reinheimer, Eric W; Swenson, Dale C; MacGillivray, Leonard R

    2015-08-01

    Thermal expansion involves a response of a material to an external stimulus that typically involves an increase in a crystallographic axis (positive thermal expansion (PTE)), although shrinking with applied heat (negative thermal expansion (NTE)) is known in rarer cases. Here, we demonstrate a means to achieve dynamic molecular motion and thermal expansions in organic solids via co-crystallizations. One co-crystal component is known to exhibit dynamic behaviour in the solid state while the second, when varied systematically, affords co-crystals with linear thermal expansion coefficients that range from colossal to nearly zero. Two co-crystals exhibit rare NTE. We expect the approach to guide the design of molecular solids that enable predesigned motion related to thermal expansion processes.

  6. Solid-state reactions to synthesize nanostructured lead selenide semiconductor powders by high-energy milling

    Energy Technology Data Exchange (ETDEWEB)

    Rojas-Chavez, H., E-mail: uu_gg_oo@yahoo.com.mx [Centro de Investigacion e Innovacion Tecnologica - IPN, Cerrada de CECATI s/n, Col. Santa Catarina, Del. Azcapotzalco (Mexico) and Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada - IPN, Legaria 694, Col. Irrigacion, Del. Miguel Hidalgo (Mexico); Reyes-Carmona, F. [Facultad de Quimica - UNAM, Circuito de la Investigacion Cientifica s/n, C.U. Del. Coyoacan (Mexico); Jaramillo-Vigueras, D. [Centro de Investigacion e Innovacion Tecnologica - IPN, Cerrada de CECATI s/n, Col. Santa Catarina, Del. Azcapotzalco (Mexico)

    2011-10-15

    Highlights: {yields} PbSe synthesized from PbO instead of Pb powder do not require an inert atmosphere. {yields} During high-energy milling oxygen has to be chemically reduced from the lead oxide. {yields} Solid-state and solid-gas chemical reactions promote both solid and gaseous products. -- Abstract: Both solid-solid and gas-solid reactions have been traced during high-energy milling of Se and PbO powders under vial (P, T) conditions in order to synthesize the PbSe phase. Chemical and thermodynamic arguments are postulated to discern the high-energy milling mechanism to transform PbO-Se micropowders onto PbSe-nanocrystals. A set of reactions were evaluated at around room temperature. Therefore an experimental campaign was designed to test the nature of reactions in the PbO-Se system during high-energy milling.

  7. Solid-state reactions to synthesize nanostructured lead selenide semiconductor powders by high-energy milling

    International Nuclear Information System (INIS)

    Rojas-Chavez, H.; Reyes-Carmona, F.; Jaramillo-Vigueras, D.

    2011-01-01

    Highlights: → PbSe synthesized from PbO instead of Pb powder do not require an inert atmosphere. → During high-energy milling oxygen has to be chemically reduced from the lead oxide. → Solid-state and solid-gas chemical reactions promote both solid and gaseous products. -- Abstract: Both solid-solid and gas-solid reactions have been traced during high-energy milling of Se and PbO powders under vial (P, T) conditions in order to synthesize the PbSe phase. Chemical and thermodynamic arguments are postulated to discern the high-energy milling mechanism to transform PbO-Se micropowders onto PbSe-nanocrystals. A set of reactions were evaluated at around room temperature. Therefore an experimental campaign was designed to test the nature of reactions in the PbO-Se system during high-energy milling.

  8. Synthesisofc-lifepo4 composite by solid state reaction method

    Science.gov (United States)

    Rahayu, I.; Hidayat, S.; Noviyanti, A. R.; Rakhmawaty, D.; Ernawati, E.

    2017-02-01

    In this research, the enhancement of LiFePO4 conductivity was conducted by doping method with carbon materials. Carbon-based materials were obtained from the mixture of sucrose, and the precursor of LiH2PO4 and α-Fe2O3 was synthesized by solid state reaction. Sintering temperature was varied at 700°C, 800°C, 900°C and 1,000°C. The result showed that C-LiFePO4 could be synthesized by using solid state reaction method. Based on the XRD and FTIR spectrums, C-LiFePO4 can be identified as the type of crystal, characterized by the appearance of sharp signal on (011), (211) and typical peak of LiFePO4 materials. The result of conductivity measurement from C-LiFePO4 at sintering temperature of 900°C and 1,000°C was 2×10-4 S/cm and 4×10-4S/cm, respectively. The conductivity value at sintering temperature of 700°C and 800°C was very small (<10-6 S/cm), which cannot be measured by the existing equipment.

  9. Vibrational-state-selected ion--molecule reaction cross sections at thermal energies

    NARCIS (Netherlands)

    Pijkeren, D. van; Boltjes, E.; Eck, J. van; Niehaus, A.

    1984-01-01

    A method designed to measure relative ion—molecule reaction rates at thermal collision energies for selected reactant ion vibrational states is described. Relative reaction rates are determined for the three endothermic reactions: H2+ (υ)(He,H)HeH+, H2+ (υ)(Ne,H)NeH+, D2+(υ)(Ne, D)NeD+, and for the

  10. Synthesis of CaTiO3:Pr persistent phosphors by a modified solid-state reaction

    International Nuclear Information System (INIS)

    Yin Shengyu; Chen Donghua; Tang Wanjun; Peng Yuhua

    2007-01-01

    Using tetra-n-butyl titanate and calcium nitrate as raw materials, the praseodymium-doped calcium titanates have been synthesized via a modified solid-state reaction. The decomposition process of the precursor, crystallization, and particle sizes of CaTiO 3 :Pr have been investigated by using thermal analysis, powder X-ray diffraction and transmission electron microscopy (TEM). TG-DTG curves and X-ray diffraction analysis indicate that crystalline calcium titanate has been synthesized at calcining temperature of 600 deg. C for 2 h. Photoluminescence and decay curves show that the sample obtained at the sintering temperature of 900 deg. C exhibited the optimal luminous property

  11. Thermal Stir Welding: A New Solid State Welding Process

    Science.gov (United States)

    Ding, R. Jeffrey

    2003-01-01

    Thermal stir welding is a new welding process developed at NASA's Marshall Space Flight Center in Huntsville, AL. Thermal stir welding is similar to friction stir welding in that it joins similar or dissimilar materials without melting the parent material. However, unlike friction stir welding, the heating, stirring and forging elements of the process are all independent of each other and are separately controlled. Furthermore, the heating element of the process can be either a solid-state process (such as a thermal blanket, induction type process, etc), or, a fusion process (YG laser, plasma torch, etc.) The separation of the heating, stirring, forging elements of the process allows more degrees of freedom for greater process control. This paper introduces the mechanics of the thermal stir welding process. In addition, weld mechanical property data is presented for selected alloys as well as metallurgical analysis.

  12. Design Considerations of a Solid State Thermal Energy Storage

    Science.gov (United States)

    Janbozorgi, Mohammad; Houssainy, Sammy; Thacker, Ariana; Ip, Peggy; Ismail, Walid; Kavehpour, Pirouz

    2016-11-01

    With the growing governmental restrictions on carbon emission, renewable energies are becoming more prevalent. A reliable use of a renewable source however requires a built-in storage to overcome the inherent intermittent nature of the available energy. Thermal design of a solid state energy storage has been investigated for optimal performance. The impact of flow regime, laminar vs. turbulent, on the design and sizing of the system is also studied. The implications of low thermal conductivity of the storage material are discussed and a design that maximizes the round trip efficiency is presented. This study was supported by Award No. EPC-14-027 Granted by California Energy Commission (CEC).

  13. Solid State Pathways towards Molecular Complexity in Space

    Science.gov (United States)

    Linnartz, Harold; Bossa, Jean-Baptiste; Bouwman, Jordy; Cuppen, Herma M.; Cuylle, Steven H.; van Dishoeck, Ewine F.; Fayolle, Edith C.; Fedoseev, Gleb; Fuchs, Guido W.; Ioppolo, Sergio; Isokoski, Karoliina; Lamberts, Thanja; Öberg, Karin I.; Romanzin, Claire; Tenenbaum, Emily; Zhen, Junfeng

    2011-12-01

    It has been a long standing problem in astrochemistry to explain how molecules can form in a highly dilute environment such as the interstellar medium. In the last decennium more and more evidence has been found that the observed mix of small and complex, stable and highly transient species in space is the cumulative result of gas phase and solid state reactions as well as gas-grain interactions. Solid state reactions on icy dust grains are specifically found to play an important role in the formation of the more complex ``organic'' compounds. In order to investigate the underlying physical and chemical processes detailed laboratory based experiments are needed that simulate surface reactions triggered by processes as different as thermal heating, photon (UV) irradiation and particle (atom, cosmic ray, electron) bombardment of interstellar ice analogues. Here, some of the latest research performed in the Sackler Laboratory for Astrophysics in Leiden, the Netherlands is reviewed. The focus is on hydrogenation, i.e., H-atom addition reactions and vacuum ultraviolet irradiation of interstellar ice analogues at astronomically relevant temperatures. It is shown that solid state processes are crucial in the chemical evolution of the interstellar medium, providing pathways towards molecular complexity in space.

  14. Thermal conductivity characteristics of dewatered sewage sludge by thermal hydrolysis reaction.

    Science.gov (United States)

    Song, Hyoung Woon; Park, Keum Joo; Han, Seong Kuk; Jung, Hee Suk

    2014-12-01

    The purpose of this study is to quantify the thermal conductivity of sewage sludge related to reaction temperature for the optimal design of a thermal hydrolysis reactor. We continuously quantified the thermal conductivity of dewatered sludge related to the reaction temperature. As the reaction temperature increased, the dewatered sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. Therefore, the bound water in the sludge cells comes out as free water, which changes the dewatered sludge from a solid phase to slurry in a liquid phase. As a result, the thermal conductivity of the sludge was more than 2.64 times lower than that of the water at 20. However, above 200, it became 0.704 W/m* degrees C, which is about 4% higher than that of water. As a result, the change in physical properties due to thermal hydrolysis appears to be an important factor for heat transfer efficiency. Implications: The thermal conductivity of dewatered sludge is an important factor the optimal design of a thermal hydrolysis reactor. The dewatered sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. The liquid phase slurry has a higher thermal conductivity than pure water.

  15. Solid state reactions of MoO3 and Na2MoO4 with (U.85,Ce.15)O2x

    International Nuclear Information System (INIS)

    Dahale, N.D.; Keskar, Meera; Singh Mudher, K.D.; Chawla, K.L.

    1999-01-01

    (U .85 ,Ce .15 )MoO 6-x was prepared by the solid state reactions of (U .85 ,Ce .15 )O 2±x with MoO 3 in air at 600 deg C. Solid state reactions of Na 2 MoO 4 with (U .85 ,Ce .15 )MoO 6.x up to 550 deg C in air led to the formation of Na 2 (U .85 ,Ce .15 )Mo 2 O 10-x and Na 2 (U .85 , Ce .15 ) 2 Mo 3 O 16-x . These compounds were characterised by x-ray and thermal methods. The x-ray powder data of (U .85 , Ce .15 ) MoO 6-x were indexed on monoclinic system whereas, data of Na 2 (U .85 ,Ce .15 ) Mo 2 O 10-x and Na 2 (U .85 ,Ce .15 ) 2 Mo 3 O 16-x were indexed on orthorhombic and monoclinic system respectively. (author)

  16. Growth behavior of LiMn2O4 particles formed by solid-state reactions in air and water vapor

    International Nuclear Information System (INIS)

    Kozawa, Takahiro; Yanagisawa, Kazumichi; Murakami, Takeshi; Naito, Makio

    2016-01-01

    Morphology control of particles formed during conventional solid-state reactions without any additives is a challenging task. Here, we propose a new strategy to control the morphology of LiMn 2 O 4 particles based on water vapor-induced growth of particles during solid-state reactions. We have investigated the synthesis and microstructural evolution of LiMn 2 O 4 particles in air and water vapor atmospheres as model reactions; LiMn 2 O 4 is used as a low-cost cathode material for lithium-ion batteries. By using spherical MnCO 3 precursor impregnated with LiOH, LiMn 2 O 4 spheres with a hollow structure were obtained in air, while angulated particles with micrometer sizes were formed in water vapor. The pore structure of the particles synthesized in water vapor was found to be affected at temperatures below 700 °C. We also show that the solid-state reaction in water vapor is a simple and valuable method for the large-scale production of particles, where the shape, size, and microstructure can be controlled. - Graphical abstract: This study has demonstrated a new strategy towards achieving morphology control without the use of additives during conventional solid-state reactions by exploiting water vapor-induced particle growth. - Highlights: • A new strategy to control the morphology of LiMn 2 O 4 particles is proposed. • Water vapor-induced particle growth is exploited in solid-state reactions. • The microstructural evolution of LiMn 2 O 4 particles is investigated. • The shape, size and microstructure can be controlled by solid-state reactions.

  17. Advanced materials for solid state hydrogen storage: “Thermal engineering issues”

    International Nuclear Information System (INIS)

    Srinivasa Murthy, S.; Anil Kumar, E.

    2014-01-01

    Hydrogen has been widely recognized as the “Energy Carrier” of the future. Efficient, reliable, economical and safe storage and delivery of hydrogen form important aspects in achieving success of the “Hydrogen Economy”. Gravimetric and volumetric storage capacities become important when one considers portable and mobile applications of hydrogen. In the case of solid state hydrogen storage, the gas is reversibly embedded (by physisorption and/or chemisorption) in a solid matrix. A wide variety of materials such as intermetallics, physisorbents, complex hydrides/alanates, metal organic frameworks, etc. have been investigated as possible storage media. This paper discusses the feasibility of lithium– and sodium–aluminum hydrides with emphasis on their thermodynamic and thermo-physical properties. Drawbacks such as poor heat transfer characteristics and poor kinetics demand special attention to the thermal design of solid state storage devices. - Highlights: • Advanced materials suitable for solid state hydrogen storage are discussed. • Issues related to thermodynamic and thermo-physical properties of hydriding materials are brought out. • Hydriding and dehydriding behavior including sorption kinetics of complex hydrides with emphasis on alanates are explained

  18. Emanation thermal analysis. Application in solid state chemistry, analytical chemistry and engineering

    International Nuclear Information System (INIS)

    Balek, V.; Tel'deshi, Yu.

    1986-01-01

    Voluminous material on application of emenation thermal analysis for investigation of solids is systematized. General concepts and historical review of development of the method are given. Methods of introduction of inert gases into solids are considered. Theoretical aspects of inert gas evolution from solids labelled by radioactive gas or its maternal isotope are stated. The methods for measuring inert gases are considered. The possibilities, limitations and perspectives of development of radiometric emanation methods for the solution of various problems of analytical chemistry and thechnology are discussed

  19. Residual thermal stresses in a solid sphere cast from a thermosetting material

    Science.gov (United States)

    Levitsky, M.; Shaffer, B. W.

    1975-01-01

    Expressions are developed for the residual thermal stresses in a solid sphere cast from a chemically hardening thermosetting material in a rigid spherical mold. The description of the heat generation rate and temperature variation is derived from a first-order chemical reaction. Solidification is described by the continuous transformation of the material from an inviscid liquidlike state into an elastic solid, with intermediate properties determined by the degree of chemical reaction. Residual stress components are obtained as functions of the parameters of the hardening process and the properties of the hardening material. Variation of the residual stresses with a nondimensionalized reaction rate parameter and the relative compressibility of the hardened material is discussed in detail.

  20. In situ Spectroscopy of Solid-State Chemical Reaction in PbBr2-Deposited CsBr Crystals

    Science.gov (United States)

    Kondo, Shin-ichi; Matsunaga, Toshihiro; Saito, Tadaaki; Asada, Hiroshi

    2003-09-01

    It is possible to measure the fundamental optical absorption spectra of CsPbBr3 and Cs4PbBr6, whose stability is predicted by the study of phase diagram in the binary system CsBr-PbBr2, by means of in situ optical absorption and reflection spectroscopy of thermally induced solid-state chemical reaction in PbBr2-deposited CsBr crystals. On heavy annealing of the crystals, the Pb2+ ions are uniformly dispersed in the crystal matrix. The present experiment provides a novel method for measuring intrinsic optical absorption of ternary metal halides and also for in situ monitoring of doping metal halide crystal with impurities (metal ions or halogen ions).

  1. Solid-state reaction in Fe/V multilayers by ion beam mixing with thermal annealing

    International Nuclear Information System (INIS)

    Borges, J.F.M.; Costa, M.I. da Jr.; Teixeira, S.R.; Cunha, J.B.M. da; Alves, M.C.M.

    2001-01-01

    We report a study on the structural and magnetic properties of iron-vanadium thin films, originally grown in multilayer form [Fe(20 A)/V(20 A)] 20 , and mixed by ion beam mixing (IBM) and a subsequent thermal treatment. The samples were structurally characterised by X-ray diffraction (XRD) in the θ-2θ geometry and X-ray absorption spectroscopy (XAS). The magnetic characterisation was made using conversion electron Moessbauer spectroscopy (CEMS). The XRD result for the as-deposited multilayer shows a high-degree crystallinity, while CEMS suggests abrupt interface, since no significant contribution from vanadium in iron is observed. After the IBM and thermal treatment, the results from XRD show an FeV solid solution indexed as a bcc-disordered structure (α phase). XAS structural results are consistent with the XRD observations. CEMS results show a magnetic moment reduction for mixed samples

  2. A green synthesis of a layered titanate, potassium lithium titanate; lower temperature solid-state reaction and improved materials performance

    International Nuclear Information System (INIS)

    Ogawa, Makoto; Morita, Masashi; Igarashi, Shota; Sato, Soh

    2013-01-01

    A layered titanate, potassium lithium titanate, with the size range from 0.1 to 30 µm was prepared to show the effects of the particle size on the materials performance. The potassium lithium titanate was prepared by solid-state reaction as reported previously, where the reaction temperature was varied. The reported temperature for the titanate preparation was higher than 800 °C, though 600 °C is good enough to obtain single-phase potassium lithium titanate. The lower temperature synthesis is cost effective and the product exhibit better performance as photocatalysts due to surface reactivity. - Graphical abstract: Finite particle of a layered titanate, potassium lithium titanate, was prepared by solid-state reaction at lower temperature to show modified materials performance. Display Omitted - Highlights: • Potassium lithium titanate was prepared by solid-state reaction. • Lower temperature reaction resulted in smaller sized particles of titanate. • 600 °C was good enough to obtain single phased potassium lithium titanate. • The product exhibited better performance as photocatalyst

  3. A Tunable Mid-Infrared Solid-State Laser with a Compact Thermal Control System

    Directory of Open Access Journals (Sweden)

    Deyang Yu

    2018-05-01

    Full Text Available Tunable mid-infrared lasers are widely used in laser spectroscopy, gas sensing and many other related areas. In order to solve heat dissipation problems and improve the environmental temperature adaptability of solid-state laser sources, a tunable all-fiber laser pumped optical parametric oscillator (OPO was established, and a compact thermal control system based on thermoelectric coolers, an automatic temperature control circuit, cooling fins, fans and heat pipes was integrated and designed for the laser. This system is compact, light and air-cooling which satisfies the demand for miniaturization of lasers. A mathematical model and method was established to estimate the cooling capacity of this thermal control system under different ambient environments. A finite-element model was built and simulated to analyze the thermal transfer process. Experiments in room and high temperature environments were carried out and showed that the substrate temperature of a pump module could be maintained at a stable value with controlled precision to 0.2 degrees, while the output power stability of the laser was within ±1%. The experimental results indicate that this compact air-cooling thermal control system could effectively solve the heat dissipation problem of mid-infrared solid-state lasers with a one hundred watts level pump module in room and high temperature environments.

  4. Growth behavior of LiMn{sub 2}O{sub 4} particles formed by solid-state reactions in air and water vapor

    Energy Technology Data Exchange (ETDEWEB)

    Kozawa, Takahiro, E-mail: t-kozawa@jwri.osaka-u.ac.jp [Joining and Welding Research Institute, Osaka University, 11–1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Yanagisawa, Kazumichi [Research Laboratory of Hydrothermal Chemistry, Faculty of Science, Kochi University, 2–5-1 Akebono-cho, Kochi 780-8520 (Japan); Murakami, Takeshi; Naito, Makio [Joining and Welding Research Institute, Osaka University, 11–1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)

    2016-11-15

    Morphology control of particles formed during conventional solid-state reactions without any additives is a challenging task. Here, we propose a new strategy to control the morphology of LiMn{sub 2}O{sub 4} particles based on water vapor-induced growth of particles during solid-state reactions. We have investigated the synthesis and microstructural evolution of LiMn{sub 2}O{sub 4} particles in air and water vapor atmospheres as model reactions; LiMn{sub 2}O{sub 4} is used as a low-cost cathode material for lithium-ion batteries. By using spherical MnCO{sub 3} precursor impregnated with LiOH, LiMn{sub 2}O{sub 4} spheres with a hollow structure were obtained in air, while angulated particles with micrometer sizes were formed in water vapor. The pore structure of the particles synthesized in water vapor was found to be affected at temperatures below 700 °C. We also show that the solid-state reaction in water vapor is a simple and valuable method for the large-scale production of particles, where the shape, size, and microstructure can be controlled. - Graphical abstract: This study has demonstrated a new strategy towards achieving morphology control without the use of additives during conventional solid-state reactions by exploiting water vapor-induced particle growth. - Highlights: • A new strategy to control the morphology of LiMn{sub 2}O{sub 4} particles is proposed. • Water vapor-induced particle growth is exploited in solid-state reactions. • The microstructural evolution of LiMn{sub 2}O{sub 4} particles is investigated. • The shape, size and microstructure can be controlled by solid-state reactions.

  5. Time-resolved X-ray absorption spectroscopy for the study of solid state reactions: synthesis of nanocrystalline barium titanate and thermal decomposition of ammonium hexachlorometallate compounds; Zeitaufgeloeste Roentgenabsorptionspektroskopie zur Untersuchung von Festkoerperreaktionen: Synthese von nanokristallinem Bariumtitanat und thermische Zersetzung von Ammoniumhexachlorometallat-Verbindungen

    Energy Technology Data Exchange (ETDEWEB)

    Rumpf, H.

    2001-07-01

    This report presents investigations on the mechanism of two different types of solid-state reactions: At first, barium titanate nanopowders were prepared through a combined polymerization and pyrolysis of a metallo-organic precursor. The mean particle size d{sub m} could be adjusted by choosing appropriate reaction temperatures and tempering atmospheres. In the present in situ study of this particular solid-phase reaction, X-ray absorption near edge structure (XANES) spectroscopy at the Ti K and Ba L{sub 3}-edges was applied in the preparation route of BaTiO{sub 3} nanopowders. A pronounced distortion of the lattice symmetry was found to occur in very fine BaTiO{sub 3} nanopowders (d{sub m} < 20 nm). Secondly, in situ XANES investigations were carried out at the Cl K, Pd L{sub 3}, Rh L{sub 3}, and Pt L{sub 3}-edges to study the mechanism of the thermal decomposition of ammonium hexachlorometallates. The results exceed structural information obtained by in situ X-ray diffraction methods and thermal analysis. Feff8 multiple scattering simulations have been carried out to disclose new intermediate phases of unknown reference compounds. (orig.)

  6. Aromatic C-Nitroso Compounds and Their Dimers: A Model for Probing the Reaction Mechanisms in Crystalline Molecular Solids

    Directory of Open Access Journals (Sweden)

    Ivana Biljan

    2017-12-01

    Full Text Available This review is focused on the dimerization and dissociation of aromatic C-nitroso compounds and their dimers, the reactions that could be used as a convenient model for studying the thermal organic solid-state reaction mechanisms. This molecular model is simple because it includes formation or breaking of only one covalent bond between two nitrogen atoms. The crystalline molecular solids of nitroso dimers (azodioxides dissociate by photolysis under the cryogenic conditions, and re-dimerize by slow warming. The thermal re-dimerization reaction is examined under the different topotactic conditions in crystals: disordering, surface defects, and phase transformations. Depending on the conditions, and on the molecular structure, aromatic C-nitroso compounds can associate to form one-dimensional polymeric structures and are able to self-assemble on gold surfaces.

  7. Low-temperature synthesis of actinide tetraborides by solid-state metathesis reactions

    Science.gov (United States)

    Lupinetti, Anthony J [Los Alamos, NM; Garcia, Eduardo [Los Alamos, NM; Abney, Kent D [Los Alamos, NM

    2004-12-14

    The synthesis of actinide tetraborides including uranium tetraboride (UB.sub.4), plutonium tetraboride (PuB.sub.4) and thorium tetraboride (ThB.sub.4) by a solid-state metathesis reaction are demonstrated. The present method significantly lowers the temperature required to .ltoreq.850.degree. C. As an example, when UCl.sub.4 is reacted with an excess of MgB.sub.2, at 850.degree. C., crystalline UB.sub.4 is formed. Powder X-ray diffraction and ICP-AES data support the reduction of UCl.sub.3 as the initial step in the reaction. The UB.sub.4 product is purified by washing water and drying.

  8. Recoil chemistry and solid state exchange in cobalt complexes : a new model

    International Nuclear Information System (INIS)

    Ramshesh, V.

    1981-01-01

    During the last thirty years considerable work has been done on various aspects of recoil chemistry and solid state exchange in cobalt complexes. Several interesting features such as 'oxygen effect', 'water of hydration effect', 'dilution with isomorphous materials', etc., have been observed. These data led workers to reject the older hypothesis based on 'fragmentation' and 'recombination' and suggest models based on exciton or electron induced exchange. However some recent data show that perhaps both the processes viz., thermal annealing in n-irradiated systems and solid state exchange are not bulk processes. This has led the author to propose a new model. In this model greater emphasis is placed on dissociation reactions followed by recombination and/or exchange reactions. (author)

  9. Numerical modeling of thermal performance: Natural convection and radiation of solid state lighting

    NARCIS (Netherlands)

    Ye, H.; Gielen, A.W.J.; Zeijl, H.W. van; Werkhoven, R.J.; Zhang, G.Q.

    2011-01-01

    The increased electrical currents used to drive light emitting diode (LED) cause significant heat generation in the solid state lighting (SSL) system. As the temperature will directly affect the maximum light output, quality, reliability and the life time of the SSL system, thermal management is a

  10. Simultaneous formation and detection of the reaction product of solid-state aspartame sweetener by FT-IR/DSC microscopic system.

    Science.gov (United States)

    Lin, S Y; Cheng, Y D

    2000-10-01

    The solid-state stability of aspartame hemihydrate (APM) sweetener during thermal treatment is important information for the food industry. The present study uses the novel technique of Fourier transform infrared microspectroscopy equipped with differential scanning calorimetry (FT-IR/DSC microscopic system) to accelerate and determine simultaneously the thermal-dependent impurity formation of solid-state APM. The results indicate a dramatic change in IR spectra from 50, 110 or 153 degrees C, which was respectively attributed to the onset temperature of water evaporation, dehydration and cyclization processes. It is suggested that the processes of dehydration and intramolecular cyclization occurred in the solid-state APM during the heating process. As an impurity, 3-carboxymethyl-6-benzyl-2,5-diketopiperazine (DKP) degraded from solid state APM via intramolecular cyclization and liberation of methanol. This was evidenced by this novel FT-IR/DSC microscopic system in a one-step procedure.

  11. Synthesising and comparing electrical properties of NTC thermistors prepared from nano powder and solid state reaction

    International Nuclear Information System (INIS)

    Azad, N.; Ghanbari Shohany, B.; Hosseini, S. M.; Kompany, A.

    2011-01-01

    In this research, NTC thermistors with composition of NiMn 2-x Co x O 4 (x = 0.4, 0.8, 1.2, 1.6) prepared by two methods: solid state reaction and sol-gel (gel-combustion). The average particle size was monitored and structure of the calcinated powders have been investigated using x-ray diffraction and tunneling electron microscopy techniques. The average particle size was estimated to be about 65 nm with the cubic and cubic + tetragonal phases for low and high cobalt concentrations, respectively. The grain size of samples verifies with scanning electron microscopy images. Upon increasing the cobalt fraction, the grain size of samples increases from about 2μm to a few μm in size. The electrical properties of these thermistors depend on the grain size. The grain size of samples made from sol-gel is smaller than from solid state reaction under the same condition. For longer sintering time of the samples prepared by gel-combustion method, the grain size was increased then the electrical parameters of nano powder improved and we obtain better results than the samples prepared from solid state reaction.

  12. Preparation and characterization of bismuth ruthenate pyrochlore via solid state reaction and sol-gel methods

    Directory of Open Access Journals (Sweden)

    Mayuree Sansernnivet

    2010-01-01

    Full Text Available Bismuth ruthenate pyrochlores, potential cathode materials for intermediate temperature solid oxide fuel cells(ITSOFCs, were prepared via solid-state and sol-gel method. Effects of the preparation routes and conditions on the phase and microstructures of the materials were investigated in this study using XRD and SEM. The study showed that the preparation method and the adding sequence of the starting meterials have a significant effect on the crystal phase and the particle size obtained. Sol-gel synthesis could yield a material with only pyrochlore structure, i.e. Bi2Ru2O7, while the solid state method yielded powder with a small amount of the secondary RuO2 phase. The sol-gel synthesis resulted in materialswith a finer particle size (~0.3-1.0 μm compared to powder synthesized via the solid state reaction method.

  13. Thermal neutron detection by means of an organic solid-state track detector

    International Nuclear Information System (INIS)

    Doerschel, B.; Streubel, G.

    1979-01-01

    Thermal neutrons can be detected by means of organic solid-state track detectors if they are combined with radiators in which charged secondary particles are produced in neutron interaction processes. The secondary particles can produce etchable tracks in the detector material. For thermal neutron fluence determination from the track densities, the thermal neutron sensitivity was calculated for cellulose triacetate detectors with LiF radiators, taking into account energy and angular distribution of the alpha particles produced in the LiF radiator. This value is in good agreement with the sensitivity measured during irradiation in different neutron fields if corrections are considered the production of etchable or visuable tracks. Measuring range and measuring accuracy meet the requirements of thermal neutron detection in personnel dosimetry. Possibilities of extending the measuring range are discussed. (author)

  14. Formation of amorphous Ti-50at.%Pt by solid state reactions during mechanical alloying

    CSIR Research Space (South Africa)

    Mahlatji, ML

    2013-10-01

    Full Text Available Mechanical alloying of an equiatomic mixture of crystalline elemental powders of Ti and Pt in a high-energy ball mill results in formation of an amorphous alloy by solid-state reactions. Mechanical alloying was carried out in an argon atmosphere...

  15. The effect of B_2O_3 flux on growth NLBCO superconductor by solid state reaction and wet-mixing methods

    International Nuclear Information System (INIS)

    Suharta, W. G.; Wendri, N.; Ratini, N.; Suarbawa, K. N.

    2016-01-01

    The synthesis of B_2O_3 flux substituted NLBCO superconductor NdBa_1_._7_5La_0_._2_5Cu_3O_7_-_∂ has been done using solid state reaction and wet-mixing methods in order to obtain homogeneous crystals and single phase. From DTA/TGA characteritations showed the synthesis process by wet-mixing requires a lower temperature than the solid state reaction in growing the superconductor NdBa_1_._7_5La_0_._2_5Cu_3O_7_-_∂. Therefore, in this research NdBa_1_._7_5La_0_._2_5Cu_3O_7_-_∂ sample calcinated at 650°C for wet-mixing method and 820°C for solid state reaction methods. The all samples was sintered at 950°C for ten hours. Crystallinity of the sample was confirmed using X-ray techniques and generally obtained sharp peaks that indicates the sample already well crystallized. Search match analyses for diffraction data gave weight fractions of impurity phase of the solid state reaction method higher than wet-mixing method. In this research showed decreasing the price of the lattice parameter about 1% with the addition of B_2O_3 flux for the both synthesis process and 2% of wet mixing process for all samples. Characterization using scanning electron microscopy (SEM) showed the distribution of crystal zise for wet-mixing method more homogeneous than solid state reaction method, with he grain size of samples is around 150–250 nm. The results of vibrating sample magnetometer (VSM) showed the paramagnetic properties for all samples.

  16. Synthesis of Ca_3CO_4O_9 via solid state reaction

    International Nuclear Information System (INIS)

    Melo, K.P.; Dutra, R.P.S.; Marques, K.A.; Junior, S.M.S.; Brasileiro, C.T.; Coutinho, S.V.C.R.; Souza, T.; Chagas, T.F.; Silva, R.M.; Macedo, D.A.

    2016-01-01

    Solid oxide fuel cells (SOFCs) stand out as the most promising today's energy conversion technologies. In the development of cathode materials for SOFC, calcium cobaltate (Ca3Co4O9, C349) appears as a potential alternative to traditional lanthanum manganites. In this work, C349 was prepared via solid state reaction of stoichiometric mixtures containing CaCO3 from mollusk shells, in natura (M1) and heat treated at 550 ° C (M2), and Co3O4 obtained by citrate method. The M1 and M2 mixtures were calcined at 800 (powder) and 900 ° C (tablets) for 12 h. The crystal structure and phase composition of the powder and the reaction products were studied by X-ray diffraction Rietveld refinement of the diffraction data. The results showed the formation of free C349 secondary stages, showing a good alternative to use waste from seafood shells as raw material for obtaining high-value ceramics.(author)

  17. Synthesis of monoclinic Celsian from Coal Fly Ash by using a one-step solid-state reaction process

    Energy Technology Data Exchange (ETDEWEB)

    Long-Gonzalez, D.; Lopez-Cuevas, J.; Gutierrez-Chavarria, C.A.; Pena, P.; Baudin, C.; Turrillas, X. [CINVESTAV, Coahuila (Mexico)

    2010-03-15

    Monoclinic (Celsian) and hexagonal (Hexacelsian) Ba1-xSrxAl{sub 2}Si2O8 solid solutions, where x=0, 0.25, 0.375, 0.5, 0.75 or 1, were synthesized by using Coal Fly Ash (CFA) as main raw material, employing a simple one-step solid-state reaction process involving thermal treatment for 5 h at 850-1300{sup o}C. Fully monoclinic Celsian was obtained at 1200{sup o} C/5 h, for SrO contents of 0.25 {<=} x {<=} 0.75. However, an optimum SrO level of 0.25 {<=} x {<=} 0.375 was recommended for the stabilization of Celsian. These synthesis conditions represent a significant improvement over the higher temperatures, longer times and/or multi-step processes needed to obtain fully monoclinic Celsian, when other raw materials are used for this purpose, according to previous literature. These results were attributed to the role of the chemical and phase constitution of CFA as well as to a likely mineralizing effect of CaO and TiO{sub 2} present in it, which enhanced the Hexacelsian to Celsian conversion.

  18. Iron based superconductors and related compounds synthesized by solid state metathesis and high temperature reactions

    International Nuclear Information System (INIS)

    Frankovsky, Rainer

    2013-01-01

    The results of this thesis can be divided into three major topics, which can also be seen as different approaches of solid state chemistry to reveal interesting features of known and unknown compounds and to develop alternative synthesis routes. Firstly, known compounds with related structural motifs to the superconducting iron-arsenides were investigated regarding their structural and physical properties. In case of La 3 Pd 4 Ge 4 the influence of Fe doping on the properties was studied, whereas in the series ZrMAs (M=Ti,V) the physical properties have not yet been reported at all and were investigated for the first time. Secondly, an alternative synthesis route has been developed for the synthesis of superconducting LaFeAsO 1-x F x . This solid state metathesis reaction distinctly increased the quality of the samples compared to conventionally prepared products. Furthermore, the reaction pathway was investigated and clarified, which helps to understand the processes during high temperature solid state metathesis reactions in general. Thirdly, this alternative synthesis route was expanded to other systems and new compounds like co-substituted LaFe 1-x Mn x AsO 1-y F y were prepared and thoroughly investigated. This led to a complex study of the interplay of magnetism, electronic and structural conditions and the occurrence of superconducting properties. The investigation and understanding of such complex coherences will probably be decisive for the further understanding of the superconducting mechanism in iron based superconductors.

  19. Solid state photon upconversion utilizing thermally activated delayed fluorescence molecules as triplet sensitizer

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Tony C.; Congreve, Daniel N.; Baldo, Marc A., E-mail: baldo@mit.edu [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2015-07-20

    The ability to upconvert light is useful for a range of applications, from biological imaging to solar cells. But modern technologies have struggled to upconvert incoherent incident light at low intensities. Here, we report solid state photon upconversion employing triplet-triplet exciton annihilation in an organic semiconductor, sensitized by a thermally activated-delayed fluorescence (TADF) dye. Compared to conventional phosphorescent sensitizers, the TADF dye maximizes the wavelength shift in upconversion due to its small singlet-triplet splitting. The efficiency of energy transfer from the TADF dye is 9.1%, and the conversion yield of sensitizer exciton pairs to singlet excitons in the annihilator is 1.1%. Our results demonstrate upconversion in solid state geometries and with non-heavy metal-based sensitizer materials.

  20. Catalytic reaction in a porous solid subject to a boundary layer flow

    Energy Technology Data Exchange (ETDEWEB)

    Mihail, R; Teddorescu, C

    1978-01-01

    A mathematical model of a boundary layer flowing past a catalytic slab was developed which included an analysis of the coupled mass and heat transfer and the heterogeneous chemical reaction. The porous flat plate was used to illustrate the interaction of boundary layer flow with chemical reaction within a porous catalytic body. The model yielded systems of transcendental equations which were solved numerically by means of a superposition integral in connection with a norm reduction procedure. A parametric study was conducted and an analysis of the possible multiplicity of steady states was developed and illustrated for the extreme case of infinite solid thermal conductivity. Tables, diagrams, graphs, and 12 references.

  1. Solid-state reaction in Ti/Ni multilayered films studied by using magneto-optical spectroscopy

    CERN Document Server

    Lee, Y P; Kim, K W; Kim, C G; Kudryavtsev, Y V; Nemoshkalenko, V V; Szymanski, B

    2000-01-01

    A comparative study of the solid-state reaction (SSR) in a series of Ti/Ni multilayered films (MLDs) with bilayer periods of 0.65-22.2 nm and a constant Ti to Ni sublayer thickness ratio was performed by using experimental and computer-simulated magneto-optical (MO) spectroscopy based on different models of MLFs, as well as x-ray diffraction (XRD). The spectral and sublayer thickness dependences of the MO properties of the Ti/Ni MLFs were explained on the basis of the electromagnetic theory. The existence of a threshold nominal Ni-sublayer thickness of about 3 nm for the as-deposited Ti/Ni MLF to observe of the equatorial Kerr effect was explained by a solid-state reaction which formed nonmagnetic alloyed regions between pure components during the MLF deposition. The SSR in the Ti/Ni MLFs, which was caused by the low temperature annealing, led to the formation of an amorphous Ti-Ni alloy and took place mainly in the Ti/Ni MLFs with ''thick'' sublayers. For the caes of Ti/Ni MLFs, the MO approach turned out to...

  2. Achievement of solid-state plasma fusion ('Cold-Fusion')

    International Nuclear Information System (INIS)

    Arata, Yoshiaki; Zhang, Yue-Chang

    1995-01-01

    Using a 'QMS' (Quadrupole Mass Spectrometer), the authors detected a significantly large amount (10 20 -10 21 [cm -3 ]) of helium ( 2 4 He), which was concluded to have been produced by a deuterium nuclear reaction within a host solid. These results were found to be fully repeatable and supported the authors' proposition that solid state plasma fusion ('Cold Fusion') can be generated in energetic deuterium Strongly Coupled Plasma ('SC-plasma'). This fusion reaction is thought to be sustained by localized 'Latticequake' in a solid-state media with the deuterium density equivalent to that of the host solid. While exploring this basic proposition, the characteristic differences when compared with ultra high temperature-state plasma fusion ('Hot Fusion') are clarified. In general, the most essential reaction product in both types of the deuterium plasma fusion is considered to be helium, irrespective of the 'well-known and/or unknown reactions', which is stored within the solid-state medium in abundance as a 'Residual Product', but which generally can not enter into nor be released from host-solid at a room temperature. Even measuring instruments with relatively poor sensitivity should be able to easily detect such residual helium. An absence of residual helium means that no nuclear fusion reaction has occurred, whereas its presence provides crucial evidence that nuclear fusion has, in fact, occurred in the solid. (author)

  3. In Situ Solid-State Reactions Monitored by X-ray Absorption Spectroscopy: Temperature-Induced Proton Transfer Leads to Chemical Shifts.

    Science.gov (United States)

    Stevens, Joanna S; Walczak, Monika; Jaye, Cherno; Fischer, Daniel A

    2016-10-24

    The dramatic colour and phase alteration with the solid-state, temperature-dependent reaction between squaric acid and 4,4'-bipyridine has been probed in situ with X-ray absorption spectroscopy. The electronic and chemical sensitivity to the local atomic environment through chemical shifts in the near-edge X-ray absorption fine structure (NEXAFS) revealed proton transfer from the acid to the bipyridine base through the change in nitrogen protonation state in the high-temperature form. Direct detection of proton transfer coupled with structural analysis elucidates the nature of the solid-state process, with intermolecular proton transfer occurring along an acid-base chain followed by a domino effect to the subsequent acid-base chains, leading to the rapid migration along the length of the crystal. NEXAFS thereby conveys the ability to monitor the nature of solid-state chemical reactions in situ, without the need for a priori information or long-range order. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. One-step simultaneous differential scanning calorimetry-FTIR microspectroscopy to quickly detect continuous pathways in the solid-state glucose/asparagine Maillard reaction.

    Science.gov (United States)

    Hwang, Deng-Fwu; Hsieh, Tzu-Feng; Lin, Shan-Yang

    2013-01-01

    The stepwise reaction pathway of the solid-state Maillard reaction between glucose (Glc) and asparagine (Asn) was investigated using simultaneous differential scanning calorimetry (DSC)-FTIR microspectroscopy. The color change and FTIR spectra of Glc-Asn physical mixtures (molar ratio = 1:1) preheated to different temperatures followed by cooling were also examined. The successive reaction products such as Schiff base intermediate, Amadori product, and decarboxylated Amadori product in the solid-state Glc-Asn Maillard reaction were first simultaneously evidenced by this unique DSC-FTIR microspectroscopy. The color changed from white to yellow-brown to dark brown, and appearance of new IR peaks confirmed the formation of Maillard reaction products. The present study clearly indicates that this unique DSC-FTIR technique not only accelerates but also detects precursors and products of the Maillard reaction in real time.

  5. Microstructure and growth kinetics of nickel silicide ultra-thin films synthesized by solid-state reactions

    Science.gov (United States)

    Coia, Cedrik

    The objective of the thesis is to develop a detailed fundamental understanding of the thermally induced solid-state reactions that lead to the formation of the NiSi. We use in situ synchrotron x-ray diffraction as well as wafer curvature measurements to monitor reactions as they occur during the annealing treatment. These analyses are complemented by ex situ transmission electron microscopy, Rutherford backscattering spectroscopy, and secondary ions mass spectroscopy. The solid-state reactions between 4 to 500 nm-thick Ni films and Si (001) are considerably more complex than previously believed. In addition to the commonly observed phases listed above, we observe the formation of three additional compounds---θ-Ni2Si, Ni31Si12 and Ni3Si2---before the complete transformation of the reacted film into NiSi. These compounds are found to co-exist laterally (within the same layer) with delta-Ni2Si and/or NiSi. The metastable compound θ-Ni2Si, which formation results from texture inheritance and rapid growth through vacancy diffusion, is present in all samples and forms at the same temperature (300+/-10°C) regardless of the initial Ni thickness. Indeed, this compound forms rapidly during ramps anneals, apparently consuming all the delta-Ni2Si for initial Ni films thickness of up to 10 nm. Its disappearance is also rapid and is correlated to both the growth of NiSi and to a surprising return of the orthorhombic delta-Ni 2Si. The formation sequence is therefore not monotonic in composition in contrast to what is usually expected in solid-state reactions. An investigation of the effect of alloying elements (Pt and Co) and impurities (B, P, As, F, N) on the Ni-Si reactions enables us to determine that nucleation plays a limiting role in the growth of metastable θ-Ni2Si and that the template provided by delta-Ni2Si is crucial in promoting this nucleation. Furthermore, reactions with amorphized and amorphous substrates indicate that the possibility of epitaxy with the Si

  6. The effect of B{sub 2}O{sub 3} flux on growth NLBCO superconductor by solid state reaction and wet-mixing methods

    Energy Technology Data Exchange (ETDEWEB)

    Suharta, W. G., E-mail: wgsuharta@gmail.com; Wendri, N.; Ratini, N.; Suarbawa, K. N. [Departement of Physics Faculty of Mathematics and Natural Science Udayana University Bali Indonesia (Indonesia)

    2016-03-11

    The synthesis of B{sub 2}O{sub 3} flux substituted NLBCO superconductor NdBa{sub 1.75}La{sub 0.25}Cu{sub 3}O{sub 7-∂} has been done using solid state reaction and wet-mixing methods in order to obtain homogeneous crystals and single phase. From DTA/TGA characteritations showed the synthesis process by wet-mixing requires a lower temperature than the solid state reaction in growing the superconductor NdBa{sub 1.75}La{sub 0.25}Cu{sub 3}O{sub 7-∂}. Therefore, in this research NdBa{sub 1.75}La{sub 0.25}Cu{sub 3}O{sub 7-∂} sample calcinated at 650°C for wet-mixing method and 820°C for solid state reaction methods. The all samples was sintered at 950°C for ten hours. Crystallinity of the sample was confirmed using X-ray techniques and generally obtained sharp peaks that indicates the sample already well crystallized. Search match analyses for diffraction data gave weight fractions of impurity phase of the solid state reaction method higher than wet-mixing method. In this research showed decreasing the price of the lattice parameter about 1% with the addition of B{sub 2}O{sub 3} flux for the both synthesis process and 2% of wet mixing process for all samples. Characterization using scanning electron microscopy (SEM) showed the distribution of crystal zise for wet-mixing method more homogeneous than solid state reaction method, with he grain size of samples is around 150–250 nm. The results of vibrating sample magnetometer (VSM) showed the paramagnetic properties for all samples.

  7. Reliability and Lifetime Prediction of Remote Phosphor Plates in Solid-State Lighting Applications Using Accelerated Degradation Testing

    NARCIS (Netherlands)

    Yazdan Mehr, M.; van Driel, W.D.; Zhang, G.Q.

    2015-01-01

    A methodology, based on accelerated degradation testing, is developed to predict the lifetime of remote phosphor plates used in solid-state lighting (SSL) applications. Both thermal stress and light intensity are used to accelerate degradation reaction in remote phosphor plates. A reliability model,

  8. Impact of organic-mineral matter interactions on thermal reaction pathways for coal model compounds

    Energy Technology Data Exchange (ETDEWEB)

    Buchanan, A.C. III; Britt, P.F.; Struss, J.A. [Oak Ridge National Lab., TN (United States). Chemical and Analytical Sciences Div.

    1995-07-01

    Coal is a complex, heterogeneous solid that includes interdispersed mineral matter. However, knowledge of organic-mineral matter interactions is embryonic, and the impact of these interactions on coal pyrolysis and liquefaction is incomplete. Clay minerals, for example, are known to be effective catalysts for organic reactions. Furthermore, clays such as montmorillonite have been proposed to be key catalysts in the thermal alteration of lignin into vitrinite during the coalification process. Recent studies by Hatcher and coworkers on the evolution of coalified woods using microscopy and NMR have led them to propose selective, acid-catalyzed, solid state reaction chemistry to account for retained structural integrity in the wood. However, the chemical feasibility of such reactions in relevant solids is difficult to demonstrate. The authors have begun a model compound study to gain a better molecular level understanding of the effects in the solid state of organic-mineral matter interactions relevant to both coal formation and processing. To satisfy the need for model compounds that remain nonvolatile solids at temperatures ranging to 450 C, model compounds are employed that are chemically bound to the surface of a fumed silica (Si-O-C{sub aryl}linkage). The organic structures currently under investigation are phenethyl phenyl ether (C{sub 6}H{sub 5}CH{sub 2}CH{sub 2}OC{sub 6}H{sub 5}) derivatives, which serve as models for {beta}-alkyl aryl ether units that are present in lignin and lignitic coals. The solid-state chemistry of these materials at 200--450 C in the presence of interdispersed acid catalysts such as small particle size silica-aluminas and montmorillonite clay will be reported. Initial focus will be on defining the potential impact of these interactions on coal pyrolysis and liquefaction.

  9. Preparation of Ultra-Fine Nickel Manganite Powders and Ceramics by a Solid-State Coordination Reaction

    NARCIS (Netherlands)

    Fang, Dao-lai; Wang, Zhongbing; Wang, Zhichun; Yang, Pinghua; Liu, W.; Liu, Wei; Winnubst, Aloysius J.A.; Chen, Chusheng

    2006-01-01

    A solid-state coordination reaction was adopted to prepare negative temperature coefficient ceramics. A mixed oxalate NiMn2(C2O4)3·6H2O, a coordination compound, was synthesized by milling a mixture of nickel acetate, manganese acetate, and oxalic acid for 5 h at room temperature. An ultrafine

  10. Magnetic properties of ZnFe2O4 nanoparticles produced by a low-temperature solid-state reaction method

    International Nuclear Information System (INIS)

    Li Fashen; Wang Haibo; Wang Li; Wang Jianbo

    2007-01-01

    ZnFe 2 O 4 nanoparticles with average grain size ranging from 40 to 60 nm behaving superparamagnetic at room temperature have been produced using a low-temperature solid-state reaction (LTSSR) method without ball-milling process. Abnormal magnetic properties such as S-shape hysteresis loops and non-zero magnetic moments were observed. ZnFe 2 O 4 nanoparticles were also synthesized using a NaOH coprecipitation method and a PVA sol-gel method to study the relationship between the preparation processes and the magnetic properties. Spin-glass behavior was observed in the low temperature solid-state reaction produced Zn ferrite in the zero-field cooled (ZFC) measurement. Our work proves that the various preparation methods will to some extent determine the properties of magnetic nanoparticles

  11. Densification of Ce0.9Gd0.1O1.95 barrier layer by in-situ solid state reaction

    DEFF Research Database (Denmark)

    Ni, De Wei; Esposito, Vincenzo

    2014-01-01

    A novel methodology, called in-situ solid state reaction (SSR), is developed and achieved for the densification of gadolinia doped ceria (CGO) barrier layer (BL) within the solid oxide fuel cell (SOFC) technology. The method is based on the combined use of impregnation technique and a designed two...

  12. Solid-solid phase change thermal storage application to space-suit battery pack

    Science.gov (United States)

    Son, Chang H.; Morehouse, Jeffrey H.

    1989-01-01

    High cell temperatures are seen as the primary safety problem in the Li-BCX space battery. The exothermic heat from the chemical reactions could raise the temperature of the lithium electrode above the melting temperature. Also, high temperature causes the cell efficiency to decrease. Solid-solid phase-change materials were used as a thermal storage medium to lower this battery cell temperature by utilizing their phase-change (latent heat storage) characteristics. Solid-solid phase-change materials focused on in this study are neopentyl glycol and pentaglycerine. Because of their favorable phase-change characteristics, these materials appear appropriate for space-suit battery pack use. The results of testing various materials are reported as thermophysical property values, and the space-suit battery operating temperature is discussed in terms of these property results.

  13. Solid-State Physics Introduction to the Theory

    CERN Document Server

    Patterson, James

    2010-01-01

    Learning Solid State Physics involves a certain degree of maturity, since it involves tying together diverse concepts from many areas of physics. The objective is to understand, in a basic way, how solid materials behave. To do this one needs both a good physical and mathematical background. One definition of Solid State Physics is it is the study of the physical (e.g. the electrical, dielectric, magnetic, elastic, and thermal) properties of solids in terms of basic physical laws. In one sense, Solid State Physics is more like chemistry than some other branches of physics because it focuses on common properties of large classes of materials. It is typical that Solid State Physics emphasizes how physics properties link to electronic structure. We have retained the term Solid Modern solid state physics came of age in the late thirties and forties and is now is part of condensed matter physics which includes liquids, soft materials, and non-crystalline solids. This solid state/condensed matter physics book begin...

  14. Solid state green synthesis and catalytic activity of CuO nanorods in thermal decomposition of potassium periodate

    Science.gov (United States)

    Patel, Vinay Kumar; Bhattacharya, Shantanu

    2017-09-01

    The present study reports a facile solid state green synthesis process using the leaf extracts of Hibiscus rosa-sinensis to synthesize CuO nanorods with average diameters of 15-20 nm and lengths up to 100 nm. The as-synthesized CuO nanorods were characterized by x-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and selected area electron diffraction. The formation mechanism of CuO nanorods has been explained by involving the individual role of amide I (amino groups) and carboxylate groups under excess hydroxyl ions released from NaOH. The catalytic activity of CuO nanorods in thermal decomposition of potassium periodate microparticles (µ-KIO4) microparticles was studied by thermo gravimetric analysis measurement. The original size (~100 µm) of commercially procured potassium periodate was reduced to microscale length scale to about one-tenth by PEG200 assisted emulsion process. The CuO nanorods prepared by solid state green route were found to catalyze the thermal decomposition of µ-KIO4 with a reduction of 18 °C in the final thermal decomposition temperature of potassium periodate.

  15. Research Update: Utilizing magnetization dynamics in solid-state thermal energy conversion

    Directory of Open Access Journals (Sweden)

    Stephen R. Boona

    2016-10-01

    Full Text Available We review the spin-Seebeck and magnon-electron drag effects in the context of solid-state energy conversion. These phenomena are driven by advective magnon-electron interactions. Heat flow through magnetic materials generates magnetization dynamics, which can strongly affect free electrons within or adjacent to the magnetic material, thereby producing magnetization-dependent (e.g., remnant electric fields. The relative strength of spin-dependent interactions means that magnon-driven effects can generate significantly larger thermoelectric power factors as compared to classical thermoelectric phenomena. This is a surprising situation in which spin-based effects are larger than purely charge-based effects, potentially enabling new approaches to thermal energy conversion.

  16. Solid State Physics Introduction to the Theory

    CERN Document Server

    Patterson, James D

    2007-01-01

    Learning Solid State Physics involves a certain degree of maturity, since it involves tying together diverse concepts from many areas of physics. The objective is to understand, in a basic way, how solid materials behave. To do this one needs both a good physical and mathematical background. One definition of Solid State Physics is it is the study of the physical (e.g. the electrical, dielectric, magnetic, elastic, and thermal) properties of solids in terms of basic physical laws. In one sense, Solid State Physics is more like chemistry than some other branches of physics because it focuses on common properties of large classes of materials. It is typical that Solid State Physics emphasizes how physics properties link to electronic structure. We have retained the term Solid State Physics, even though Condensed Matter Physics is more commonly used. Condensed Matter Physics includes liquids and non-crystalline solids such as glass, which we shall not discuss in detail. Modern Solid State Physics came of age in ...

  17. Absolute efficiency calibration of 6LiF-based solid state thermal neutron detectors

    Science.gov (United States)

    Finocchiaro, Paolo; Cosentino, Luigi; Lo Meo, Sergio; Nolte, Ralf; Radeck, Desiree

    2018-03-01

    The demand for new thermal neutron detectors as an alternative to 3He tubes in research, industrial, safety and homeland security applications, is growing. These needs have triggered research and development activities about new generations of thermal neutron detectors, characterized by reasonable efficiency and gamma rejection comparable to 3He tubes. In this paper we show the state of the art of a promising low-cost technique, based on commercial solid state silicon detectors coupled with thin neutron converter layers of 6LiF deposited onto carbon fiber substrates. A few configurations were studied with the GEANT4 simulation code, and the intrinsic efficiency of the corresponding detectors was calibrated at the PTB Thermal Neutron Calibration Facility. The results show that the measured intrinsic detection efficiency is well reproduced by the simulations, therefore validating the simulation tool in view of new designs. These neutron detectors have also been tested at neutron beam facilities like ISIS (Rutherford Appleton Laboratory, UK) and n_TOF (CERN) where a few samples are already in operation for beam flux and 2D profile measurements. Forthcoming applications are foreseen for the online monitoring of spent nuclear fuel casks in interim storage sites.

  18. Nickel Oxide (NiO nanoparticles prepared by solid-state thermal decomposition of Nickel (II schiff base precursor

    Directory of Open Access Journals (Sweden)

    Aliakbar Dehno Khalaji

    2015-06-01

    Full Text Available In this paper, plate-like NiO nanoparticles were prepared by one-pot solid-state thermal decomposition of nickel (II Schiff base complex as new precursor. First, the nickel (II Schiff base precursor was prepared by solid-state grinding using nickel (II nitrate hexahydrate, Ni(NO32∙6H2O, and the Schiff base ligand N,N′-bis-(salicylidene benzene-1,4-diamine for 30 min without using any solvent, catalyst, template or surfactant. It was characterized by Fourier Transform Infrared spectroscopy (FT-IR and elemental analysis (CHN. The resultant solid was subsequently annealed in the electrical furnace at 450 °C for 3 h in air atmosphere. Nanoparticles of NiO were produced and characterized by X-ray powder diffraction (XRD at 2θ degree 0-140°, FT-IR spectroscopy, scanning electron microscopy (SEM and transmission electron microscopy (TEM. The XRD and FT-IR results showed that the product is pure and has good crystallinity with cubic structure because no characteristic peaks of impurity were observed, while the SEM and TEM results showed that the obtained product is tiny, aggregated with plate-like shape, narrow size distribution with an average size between 10-40 nm. Results show that the solid state thermal decomposition method is simple, environmentally friendly, safe and suitable for preparation of NiO nanoparticles. This method can also be used to synthesize nanoparticles of other metal oxides.

  19. CuInSe2 nano-crystallite reaction kinetics using solid state reaction from Cu2Se and In2Se3 powders

    International Nuclear Information System (INIS)

    Hsiang, Hsing-I; Lu, Li-Hsin; Chang, Yu-Lun; Ray, Dahtong; Yen, Fu-Su

    2011-01-01

    Highlights: → CuInSe 2 phase increased gradually accompanied with a decrease in γ-In 2 Se 3 and no intermediate phase during calcination. → CuInSe 2 formation from Cu 2 Se and In 2 Se 3 powders follows a one-dimensional diffusion-controlled reaction with apparent activation energy of about 122.5 kJ/mol. → The solid reaction kinetics may be dominated by the diffusion of In 3+ ions. - Abstract: The reaction mechanism and CuInSe 2 formation kinetics using a solid state reaction from Cu 2 Se and In 2 Se 3 powders synthesized using a heating up process were investigated using X-ray diffractomy (XRD) and transmission electron microscopy (TEM). It was observed that the CuInSe 2 phase increased gradually, accompanied with a decrease in γ-In 2 Se 3 with no intermediate phase as the calcination temperature and soaking time were increased. The reaction kinetics was analyzed using the Avrami and polynomial kinetic model, suggesting that CuInSe 2 formation from Cu 2 Se and In 2 Se 3 powders follows a diffusion-controlled reaction with an apparent activation energy of about 122.5-182.3 kJ/mol. Cu 2 Se and In 2 Se 3 phases react and directly transform into CIS without the occurrence of any intermediate phase and the size of the newly formed CuInSe 2 crystallites was close to that of the Cu 2 Se reactant particle based on the TEM results, which indicated that the solid reaction kinetics may be dominated by the diffusion of In 3+ ions.

  20. Design of laser-driven SiO2-YAG:Ce composite thick film: Facile synthesis, robust thermal performance, and application in solid-state laser lighting

    Science.gov (United States)

    Xu, Jian; Liu, Bingguo; Liu, Zhiwen; Gong, Yuxuan; Hu, Baofu; Wang, Jian; Li, Hui; Wang, Xinliang; Du, Baoli

    2018-01-01

    In recent times, there have been rapid advances in the solid-state laser lighting technology. Due to the large amounts of heat accumulated from the high flux laser radiation, color conversion materials used in solid-state laser lighting devices should possess high durability, high thermal conductivity, and low thermal quenching. The aim of this study is to develop a thermally robust SiO2-YAG:Ce composite thick film (CTF) for high-power solid-state laser lighting applications. Commercial colloidal silica which was used as the source of SiO2, played the roles of an adhesive, a filler, and a protecting agent. Compared to the YAG:Ce powder, the CTF exhibits remarkable thermal stability (11.3% intensity drop at 200 °C) and durability (4.5% intensity drop after 1000 h, at 85 °C and 85% humidity). Furthermore, the effects of the substrate material and the thickness of the CTF on the laser lighting performance were investigated in terms of their thermal quenching and luminescence saturation behaviors, respectively. The CTF with a thickness of 50 μm on a sapphire substrate does not show luminescence saturation, despite a high-power density of incident radiation i.e. 20 W/mm2. These results demonstrate the potential applicability of the CTF in solid-state laser lighting devices.

  1. An Integrated Approach to Thermal Analysis of Pharmaceutical Solids

    Science.gov (United States)

    Riley, Shelley R. Rabel

    2015-01-01

    A three-tiered experiment for undergraduate Instrumental Analysis students is presented in which students characterize the solid-state thermal behavior of an active pharmaceutical ingredient (acetaminophen) and excipient (a-lactose hydrate) using differential scanning calorimetry, thermogravimetric analysis, and thermal microscopy. Students are…

  2. High-pressure synthesis of rhombohedral α-AgGaO{sub 2} via direct solid state reaction

    Energy Technology Data Exchange (ETDEWEB)

    Akhtar, Meysam [Department of Physics and Astronomy, University of Louisville, 102 Natural Science Building, Louisville, KY 40292 (United States); Menon, Madhu [Center for Computational Sciences, University of Kentucky, 325 McVey Hall, Lexington, KY 40506 (United States); Sunkara, Mahendra [Conn Center for Renewable Energy Research, University of Louisville, Ernst Hall Room 102A, Louisville, KY 40292 (United States); Sumanasekera, Gamini [Department of Physics and Astronomy, University of Louisville, 102 Natural Science Building, Louisville, KY 40292 (United States); Conn Center for Renewable Energy Research, University of Louisville, Ernst Hall Room 102A, Louisville, KY 40292 (United States); Durygin, Andriy [Center for the Study of Matter at Extreme Conditions, Florida International University, VH 140, University Park, Miami, FL 33199 (United States); Jasinski, Jacek B., E-mail: jacek.jasinski@louisville.edu [Conn Center for Renewable Energy Research, University of Louisville, Ernst Hall Room 102A, Louisville, KY 40292 (United States)

    2015-08-25

    Highlights: • Direct synthesis of α-AgGaO{sub 2} via a solid state reaction of Ag{sub 2}O and Ga{sub 2}O{sub 3} powders. • Utilizing high pressure diamond anvil cell to facilitate solid state reaction. • Experimental and theoretical study of vibrational modes for α-AgGaO{sub 2}. • Extensive characterization of synthesized α-AgGaO{sub 2} samples. • GGA + U formalism-based DFT calculations of electronic structure and band gap in α-AgGaO{sub 2}. - Abstract: In this work, we demonstrate the application of high pressure conditions to enable the direct synthesis of α-AgGaO{sub 2} via a solid state reaction of Ag{sub 2}O and Ga{sub 2}O{sub 3}. Synthesis experiments were carried out at pressures and temperatures up to ∼10 GPa and ∼600 °C, respectively, using a resistively-heated diamond anvil cell. Thus synthesized α-AgGaO{sub 2} samples were characterized and their chemical composition and crystal structure were confirmed. In particular, electron diffraction confirmed the rhombohedral delafossite crystal structure of the synthesized AgGaO{sub 2} and its corresponding lattice parameters of a = 2.99 Å and c = 18.43 Å. The vibrational modes analysis was also conducted using a combination of ab initio density functional theory (DFT) and Raman spectroscopy. This analysis yielded good agreement between the calculated Raman-active modes and experimental Raman data. Finally, the application of the GGA + U formalism-based on DFT to calculate the electronic band structure of α-AgGaO{sub 2} provided a more realistic theoretical band gap value than those reported previously.

  3. Rapid Synthesis of Lead Oxide Nanorods by One-step Solid-state Chemical Reaction at Room Temperature

    Institute of Scientific and Technical Information of China (English)

    CAO, Ya-Li(曹亚丽); JIA, Dian-Zeng(贾殿赠); LIU, Lang(刘浪); LUO, Jian-Min(骆建敏)

    2004-01-01

    A simple and facile method was reported to synthesize lead oxide nanorods. Nanorods of lead oxide were obtained directly from grinding solid metal salt and sodium hydroxide in agate mortar with the assistance of a suitable nonionic surfactant in only one step, which is different from the result of hydroxide in solution. The product has been characterized by XRD, TEM and SEM. The formation mechanism of rod-like morphology is discussed and the surfactant plays an important soft-template role in modifying the interface of solid-state reaction and according process of rod-formation.

  4. Thermal degradation of polyoxymethylene produced by solid-state polymerization

    International Nuclear Information System (INIS)

    Pearson, A.W.N.; Groves, G.W.

    1976-01-01

    The thermal degradation of polyoxymethylene produced by the solid-state polymerization of trioxane crystals was studied. Changes in small-angle and wide-angle x-ray patterns, weight loss, and density were measured in specimens heated in air at 175, 185, and 195 0 C. The polyoxymethylene contained materials in two different crystallographic orientations which behaved differently. Material in the so-called ''twin'' orientation melted preferentially at 185 and 195 0 C, and at 185 0 C resolidified on cooling in parallel to the main orientation, in a lamellar structure. At 195 0 C, randomly oriented material was produced on resolidification. At 175 0 C, there was no evidence of melting or the formation of a lamellar structure, but the twin material was preferentially degraded so that only material in the main orientation remained after a time of 1500 min. The more rapid loss by degradation of the twin material was attributed to its having a lower molecular weight than the material in the main orientation

  5. Thermal characterization of polymer matrix composites containing microencapsulated paraffin in solid or liquid state

    International Nuclear Information System (INIS)

    Sari-Bey, Sana; Fois, Magali; Krupa, Igor; Ibos, Laurent; Benyoucef, Boumédiène

    2014-01-01

    Highlights: • Thermal characterization of PCL/Micronal composites. • Melting enthalpy and heat capacity measured by DSC. • Interest: have measured thermal properties at different temperatures. • Thermophysical properties measurement temperatures chosen outside phase changes. • Characteristics useful to model composites heat transfer for LHTES applications. - Abstract: This work focuses on the study of heat transfer mechanisms in composites materials which may be used for Latent Heat Thermal Energy Storage applications. These composites contain phase change material (PCM) which can absorb and release energy during thermal cycling. PCM’s used here are paraffins microencapsulated in poly(methylmethacrylate); microencapsulation avoids the flow of paraffin when it is in the liquid state. Samples with different paraffin weight fractions and particles shape and distribution were studied in this work. Scanning Electron Microscopy and Differential Scanning Calorimetry were used to determine morphology and perform measurements of phase changes temperatures, enthalpies and heat capacity respectively. Further, a periodic method (DICO) allowed measuring thermal conductivity (λ) and diffusivity (a) of the composites at temperatures below and above of the paraffin phase change from crystalline solid to isotropic liquid

  6. Semiempirical equations for modeling solid-state kinetics based on a Maxwell-Boltzmann distribution of activation energies: applications to a polymorphic transformation under crystallization slurry conditions and to the thermal decomposition of AgMnO4 crystals.

    Science.gov (United States)

    Skrdla, Peter J; Robertson, Rebecca T

    2005-06-02

    Many solid-state reactions and phase transformations performed under isothermal conditions give rise to asymmetric, sigmoidally shaped conversion-time (x-t) profiles. The mathematical treatment of such curves, as well as their physical interpretation, is often challenging. In this work, the functional form of a Maxwell-Boltzmann (M-B) distribution is used to describe the distribution of activation energies for the reagent solids, which, when coupled with an integrated first-order rate expression, yields a novel semiempirical equation that may offer better success in the modeling of solid-state kinetics. In this approach, the Arrhenius equation is used to relate the distribution of activation energies to a corresponding distribution of rate constants for the individual molecules in the reagent solids. This distribution of molecular rate constants is then correlated to the (observable) reaction time in the derivation of the model equation. In addition to providing a versatile treatment for asymmetric, sigmoidal reaction curves, another key advantage of our equation over other models is that the start time of conversion is uniquely defined at t = 0. We demonstrate the ability of our simple, two-parameter equation to successfully model the experimental x-t data for the polymorphic transformation of a pharmaceutical compound under crystallization slurry (i.e., heterogeneous) conditions. Additionally, we use a modification of this equation to model the kinetics of a historically significant, homogeneous solid-state reaction: the thermal decomposition of AgMnO4 crystals. The potential broad applicability of our statistical (i.e., dispersive) kinetic approach makes it a potentially attractive alternative to existing models/approaches.

  7. Direct determination of enthalpies of solid phase reactions by immersion method; Determination directe des enthalpies de reaction en phase solide par une methode de plongee

    Energy Technology Data Exchange (ETDEWEB)

    Roux, A; Richard, M; Eyraud, L; Stevanovic, M; Elston, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    It is not generally possible to measure the enthalpy change corresponding to solid phase reactions using the dynamic differential thermal analysis method because these reactions are usually too slow at the temperature of operation of present equipment. A ballistic differential thermal analysis apparatus has been developed which is based on an immersion-compensation method; it overcomes the difficulties previously encountered. This apparatus has been used after calibration for determining the enthalpies of formation of calcium and cadmium titanates. and also the Wigner energies of BeO, MgO and Al{sub 2}O{sub 3} samples irradiated at variable dose at a temperature of under 100 deg. C. (authors) [French] Il n'est generalement pas possible de mesurer la variation d'enthalpie correspondant aux reactions en phase solide par la methode d'analyse thermique differentielle dynamique. En effet, ces reactions sont le plus souvent trop lentes aux temperatures d'utilisation des dispositifs actuels. Un appareil d'analyse thermique differentielle balistique, base sur une methode de plongee avec compensation, a ete mis au point et permet de surmonter les difficultes precedentes. Apres etalonnages, cet appareil a ete utilise pour la determination des enthalpies de formation du titanate de calcium et du titanate de cadmium ainsi que pour celle des energies Wigner emmagasinees dans des echantillons de BeO, MgO et Al{sub 2}O{sub 3} irradies a une temperature inferieure a 100 deg. C et a differentes doses. (auteurs)

  8. Solid state thermal rectifier

    Science.gov (United States)

    None

    2016-07-05

    Thermal rectifiers using linear nanostructures as core thermal conductors have been fabricated. A high mass density material is added preferentially to one end of the nanostructures to produce an axially non-uniform mass distribution. The resulting nanoscale system conducts heat asymmetrically with greatest heat flow in the direction of decreasing mass density. Thermal rectification has been demonstrated for linear nanostructures that are electrical insulators, such as boron nitride nanotubes, and for nanostructures that are conductive, such as carbon nanotubes.

  9. Thermal pressure and isochoric thermal conductivity of solid CO2

    International Nuclear Information System (INIS)

    Purs'kij, O.Yi.

    2005-01-01

    The analysis of the correlation between the thermal pressure and the isochoric thermal conductivity of solid CO 2 has been carried out. The temperature dependences of the thermal pressure and isochoric thermal conductivity for samples with various molar volumes have been obtained. The isothermal pressure dependences of the thermal conductivity of solid CO 2 have been calculated. The form of the temperature dependence of the isochoric thermal conductivity taking the thermal pressure into account has been revealed. Behaviour of the isochoric thermal conductivity is explained by phonon-phonon interaction and additional influence of the thermal pressure

  10. Solid state nuclear track detection principles, methods and applications

    CERN Document Server

    Durrani, S A; ter Haar, D

    1987-01-01

    Solid State Nuclear Track Detection: Principles, Methods and Applications is the second book written by the authors after Nuclear Tracks in Solids: Principles and Applications. The book is meant as an introduction to the subject solid state of nuclear track detection. The text covers the interactions of charged particles with matter; the nature of the charged-particle track; the methodology and geometry of track etching; thermal fading of latent damage trails on tracks; the use of dielectric track recorders in particle identification; radiation dossimetry; and solid state nuclear track detecti

  11. Thermal energy storage for solar power generation - State of the art

    Science.gov (United States)

    Shukla, K. N.

    1981-12-01

    High temperature storage for applications in solar-thermal electric systems is considered. Noting that thermal storage is in either the form of latent, sensible or chemically stored heat, sensible heat storage is stressed as the most developed of the thermal storage technologies, spanning direct heating of a storage medium from 120-1250 C. Current methods involve solids, packed beds, fluidized beds, liquids, hot water, organic liquids, and inorganic liquids and molten salts. Latent heat storage comprises phase-change materials that move from solid to liquid with addition of heat and liquid to solid with the removal of heat. Metals or inorganic salts are candidates, and the energy balances are outlined. Finally, chemical heat storage is examined, showing possible high energy densities through catalytic, thermal dissociation reactions.

  12. Thermal physics of gas-thermal coatings formation processes. State of investigations

    International Nuclear Information System (INIS)

    Fialko, N.M.; Prokopov, V.G.; Meranova, N.O.; Borisov, Yu.S.; Korzhik, V.N.; Sherenkovskaya, G.P.; AN Ukrainskoj SSR, Kiev

    1993-01-01

    The analysis of state of investigations of gas-thermal coatings formation processes in presented. Classification of approaches to mathematical simulation of thermal phenomena studies is offered. The general characteristics of three main approaches to the analysis of heat transport processes is given. Some problems of mathematical simulation of single particle thermal interaction with solid surface are considered in details. The main physical assumptions are analysed

  13. Facilitated Oxygen Chemisorption in Heteroatom-Doped Carbon for Improved Oxygen Reaction Activity in All-Solid-State Zinc-Air Batteries.

    Science.gov (United States)

    Liu, Sisi; Wang, Mengfan; Sun, Xinyi; Xu, Na; Liu, Jie; Wang, Yuzhou; Qian, Tao; Yan, Chenglin

    2018-01-01

    Driven by the intensified demand for energy storage systems with high-power density and safety, all-solid-state zinc-air batteries have drawn extensive attention. However, the electrocatalyst active sites and the underlying mechanisms occurring in zinc-air batteries remain confusing due to the lack of in situ analytical techniques. In this work, the in situ observations, including X-ray diffraction and Raman spectroscopy, of a heteroatom-doped carbon air cathode are reported, in which the chemisorption of oxygen molecules and oxygen-containing intermediates on the carbon material can be facilitated by the electron deficiency caused by heteroatom doping, thus improving the oxygen reaction activity for zinc-air batteries. As expected, solid-state zinc-air batteries equipped with such air cathodes exhibit superior reversibility and durability. This work thus provides a profound understanding of the reaction principles of heteroatom-doped carbon materials in zinc-air batteries. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Constant rate thermal analysis of a dehydrogenation reaction

    Czech Academy of Sciences Publication Activity Database

    Perejon, A.; Perez-Maqueda, L. A.; Sanchez-Jimenez, P.E.; Criado, J. M.; Murafa, Nataliya; Šubrt, Jan

    2016-01-01

    Roč. 6, č. 84 (2016), s. 81454-81460 ISSN 2046-2069 Institutional support: RVO:61388980 Keywords : solid-state reaction s * hydrogen storage properties * milled magnesium hydride Subject RIV: CA - Inorganic Chemistry Impact factor: 3.108, year: 2016

  15. Thermoelectric Properties of the Perovskite-Type Oxide SrTi1-xNbxO3 Synthesized by Solid-State Reaction Method

    Science.gov (United States)

    Khan, Tamal Tahsin; Ur, Soon-Chul

    2018-05-01

    The perovskite-type oxide materials SrTi1-xNbxO3 (X = .02, 0.03, 0.04, 0.05 and 0.06) were synthesized by the conventional solid-state reaction method and the thermoelectric properties in terms of Nb doping at the B-site in the oxides were investigated in this study. The formation of single phase cubic perovskite structure was confirmed by the powder X-ray diffraction analysis. Negative conduction is shown in this materials system. The absolute value of Seebeck coefficient increased with increasing temperature over the measured temperature. The electrical conductivity decreased monotonically with increasing temperature, showing degenerating conduction behavior. The thermal conductivity, k, generally decreased with increasing temperature. The power factor increased with increasing Nb-doping level up to 5.0 mol% and hence the dimensionless figure of merit ZT, increased up to 5.0 mol%. The maximum ZT value was observed for SrTi0.95Nb0.05O3 at 873 K.

  16. Solid State Lighting Reliability Components to Systems

    CERN Document Server

    Fan, XJ

    2013-01-01

    Solid State Lighting Reliability: Components to Systems begins with an explanation of the major benefits of solid state lighting (SSL) when compared to conventional lighting systems including but not limited to long useful lifetimes of 50,000 (or more) hours and high efficacy. When designing effective devices that take advantage of SSL capabilities the reliability of internal components (optics, drive electronics, controls, thermal design) take on critical importance. As such a detailed discussion of reliability from performance at the device level to sub components is included as well as the integrated systems of SSL modules, lamps and luminaires including various failure modes, reliability testing and reliability performance. This book also: Covers the essential reliability theories and practices for current and future development of Solid State Lighting components and systems Provides a systematic overview for not only the state-of-the-art, but also future roadmap and perspectives of Solid State Lighting r...

  17. The role of MgCl2 compounds in preparation of Tin oxide micro particles by one-step solid - state chemical reaction method and characterization of microstructure

    International Nuclear Information System (INIS)

    Hojabry, A.; Rezainik, Y.; Abdoljavad, N.; Moghimi, N.; Shakib, M.

    2007-01-01

    In this paper, Tin oxide (SnO 2 ) nano crystals have been synthesized by one-step solid-state chemical reactions method. In the first step, the powder of SnCl 4 . 5H 2 O was mixed with MgCl 2 and Mg(OH) 2 with a weight ratio of Sn to Mg (2:1) in the air atmosphere at room, and then annealed at 200 d egree C , 400 d egree C and 600 d egree C in air for 4 h to give different size of nanoparticles. This method is a simple, efficient and economic preparation for SnO 2 nanoparticles with adjustable grain sizes in the range of 7-32 nm in high yield. The microstructure and morphology of SnO 2 nanoparticles have been studied by X-ray diffraction (XRD), scanning electron microscopy and thermal analysis (thermogravimetric analysis -differential thermal analysis).

  18. Stoichiometric control in Bi4Ti3O12 synthesis by novel hybrid solid state reaction

    DEFF Research Database (Denmark)

    Gadea, C.; Phatharapeetranun, N.; Ksapabutr, B.

    2018-01-01

    The synthesis of bismuth titanate Bi4Ti3O12 (BiT) is performed via a novel solid state reaction. The reaction is designed to control the stoichiometric content of the highly volatile element, i.e. Bi. The chemical route consists in trapping bismuth oxide colloids in a stabilized titanium based sol...

  19. Face-to-Face Packing of 2,3,9,10-Tetrasubstituted Pentacene Derivatives Revealed through a Solid State [4 + 4] Thermal Cycloaddition and Molecular Dynamic Simulation.

    Science.gov (United States)

    Pal, Bikash; Lin, Bo-Chao; Dela Cerna, Mark Vincent Carreon; Hsu, Chao-Ping; Lin, Chih-Hsiu

    2016-08-05

    2,3,9,10-Substituted pentacene tetraesters and pentacene diester-dinitriles were synthesized. These pentacene derivatives underwent an unusual solid state [4 + 4] thermal dimerization with good efficiency and complete stereoselectivity. This observation indicates this series of pentacene derivatives adopt π-π stacking geometry with large mutual overlap in solid state. This notion was confirmed by molecualr dynamic simulation.

  20. Solid-state reaction mechanism and microwave dielectric properties of CaTiO3–LaAlO3 ceramics

    International Nuclear Information System (INIS)

    Jiang, Juan; Fang, Danhua; Lu, Chao; Dou, Zhanming; Wang, Gan; Zhang, Fan; Zhang, Tianjin

    2015-01-01

    Highlights: • CaTiO 3 –LaAlO 3 perovskite ceramics were prepared by four sintering reaction routes. • The solid-state reaction mechanism was investigated by XRD and TG/DSC techniques. • Sintering routes had more influence on the parameters of Q × f and τ f than on ε r . - Abstract: 0.675CaTiO 3 –0.325LaAlO 3 perovskite ceramics were prepared by a conventional sintering process through four reaction routes. The solid-state reaction mechanisms were investigated by X-ray diffraction and thermogravimetric/differential scanning calorimetric analysis techniques. The results show that interactions occurred between mixtures of CaCO 3 and TiO 2 as well as La 2 O 3 and Al 2 O 3 , and they can influence the sintering behavior of the mixtures. Prior to the formation of solid solutions, the perovskite phases CaTiO 3 and LaAlO 3 were formed regardless of the combination of oxide powders used as reagents. From the powder mixtures which were calcined at 1200 °C, a Ca-rich Ca 9 Al 6 O 18 phase was present at 1400 °C if free La 2 O 3 and Al 2 O 3 used in the reaction mixtures. Ca-rich phases were also formed at higher temperature (1450 °C) if LaAlO 3 was present. The densities of the ceramics obtained by the four routes were different at specific sintering temperatures, and the highest density was obtained for the reaction route two. Results indicated that the preparation pathways had more influence on Q × f and temperature coefficient of the resonant frequency (τ f ) than on the dielectric constants (ε r ), and Q × f decreased and τ f increased rapidly when the secondary phase presented. Route four is considered as an optimal pathway for the preparation of 0.675CaTiO 3 –0.325LaAlO 3 ceramics.

  1. Thermally activated reaction–diffusion-controlled chemical bulk reactions of gases and solids

    Directory of Open Access Journals (Sweden)

    S. Möller

    2015-01-01

    Full Text Available The chemical kinetics of the reaction of thin films with reactive gases is investigated. The removal of thin films using thermally activated solid–gas to gas reactions is a method to in-situ control deposition inventory in vacuum and plasma vessels. Significant scatter of experimental deposit removal rates at apparently similar conditions was observed in the past, highlighting the need for understanding the underlying processes. A model based on the presence of reactive gas in the films bulk and chemical kinetics is presented. The model describes the diffusion of reactive gas into the film and its chemical interaction with film constituents in the bulk using a stationary reaction–diffusion equation. This yields the reactive gas concentration and reaction rates. Diffusion and reaction rate limitations are depicted in parameter studies. Comparison with literature data on tokamak co-deposit removal results in good agreement of removal rates as a function of pressure, film thickness and temperature.

  2. Effect of excited states on thermonuclear reaction rates

    International Nuclear Information System (INIS)

    Sargood, D.G.

    1983-01-01

    Values of the ratio of the thermonuclear reaction rate of a reaction, with target nuclei in a thermal distribution of energy states, to the reaction rate with all target nuclei in their ground states are tabulated for neutron, proton and α-particle induced reactions on the naturally occurring nuclei from 20 Ne to 70 Zn, at temperatures of 1, 2, 3.5 and 5x10 9 K. The ratios are determined from reaction rates based on statistical model cross sections

  3. In Situ Imaging the Oxygen Reduction Reactions of Solid State Na-O2 Batteries with CuO Nanowires as the Air Cathode.

    Science.gov (United States)

    Liu, Qiunan; Yang, Tingting; Du, Congcong; Tang, Yongfu; Sun, Yong; Jia, Peng; Chen, Jingzhao; Ye, Hongjun; Shen, Tongde; Peng, Qiuming; Zhang, Liqiang; Huang, Jianyu

    2018-05-14

    We report real time imaging of the oxygen reduction reactions (ORRs) in all solid state sodium oxygen batteries (SOBs) with CuO nanowires (NWs) as the air cathode in an aberration-corrected environmental transmission electron microscope under an oxygen environment. The ORR occurred in a distinct two-step reaction, namely, a first conversion reaction followed by a second multiple ORR. In the former, CuO was first converted to Cu 2 O and then to Cu; in the latter, NaO 2 formed first, followed by its disproportionation to Na 2 O 2 and O 2 . Concurrent with the two distinct electrochemical reactions, the CuO NWs experienced multiple consecutive large volume expansions. It is evident that the freshly formed ultrafine-grained Cu in the conversion reaction catalyzed the latter one-electron-transfer ORR, leading to the formation of NaO 2 . Remarkably, no carbonate formation was detected in the oxygen cathode after cycling due to the absence of carbon source in the whole battery setup. These results provide fundamental understanding into the oxygen chemistry in the carbonless air cathode in all solid state Na-O 2 batteries.

  4. Coherent diffractive imaging of solid state reactions in zinc oxide crystals

    Science.gov (United States)

    Leake, Steven J.; Harder, Ross; Robinson, Ian K.

    2011-11-01

    We investigated the doping of zinc oxide (ZnO) microcrystals with iron and nickel via in situ coherent x-ray diffractive imaging (CXDI) in vacuum. Evaporated thin metal films were deposited onto the ZnO microcrystals. A single crystal was selected and tracked through annealing cycles. A solid state reaction was observed in both iron and nickel experiments using CXDI. A combination of the shrink wrap and guided hybrid-input-output phasing methods were applied to retrieve the electron density. The resolution was 33 nm (half order) determined via the phase retrieval transfer function. The resulting images are nevertheless sensitive to sub-angstrom displacements. The exterior of the microcrystal was found to degrade dramatically. The annealing of ZnO microcrystals coated with metal thin films proved an unsuitable doping method. In addition the observed defect structure of one crystal was attributed to the presence of an array of defects and was found to change upon annealing.

  5. Operando Solid-State NMR Observation of Solvent-Mediated Adsorption-Reaction of Carbohydrates in Zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Long; Alamillo, Ricardo; Elliott, William A.; Andersen, Amity; Hoyt, David W.; Walter, Eric D.; Han, Kee Sung; Washton, Nancy M.; Rioux, Robert M.; Dumesic, James A.; Scott, Susannah L.

    2017-04-18

    Liquid-phase processing of molecules using heterogeneous catalysts – an important strategy for obtaining renewable chemicals sustainably from biomass – involves reactions that occur at solid-liquid interfaces. In glucose isomerization catalyzed by basic faujasite zeolites, the catalytic activity depends strongly on the solvent composition: initially, it declines precipitously when water is mixed with a small amount of the organic co-solvent γ-valerolactone (GVL), then recovers as the GVL content increases. Using solid-state 13C NMR spectroscopy, we observed glucose isomers located inside the zeolite pores directly, and followed their transformations into fructose and mannose in real time. At low GVL concentrations, glucose is depleted in the zeolite pores relative to the liquid phase, while higher GVL concentrations in solution drive glucose inside the pores, resulting in up to a 32 enhancement in the local glucose concentration. Although their populations exchange rapidly, molecules present at the reactive interface experience a significantly different environment from the bulk solution.

  6. Reaction of hydrogen atoms produced by radiolysis and photolysis in solid phase at 4 and 77 K

    International Nuclear Information System (INIS)

    Miyazaki, Tetsuo

    1991-01-01

    The behavior of H atoms in the solid phase has been reviewed with special attention to comparison of H atoms produced by radiolysis with those produced by photolysis. The paper consists of three parts. I -Production of H atoms: (1) the experimental results which indicate H-atom formation in the radiolysis of solid alkane are summarized; (2) ESR saturation behavior of trapped H atoms depends upon the method of H-atom-production, i.e. photolysis or radiolysis, and upon the initial energy of H atoms in the photolysis. II - Diffusion of H atoms: (1) activation energies for thermally-activated diffusion of H atoms are shown; (2) quantum diffusion of H atoms in solid H 2 is explained in terms of repetition of tunneling reaction H 2 + H → H + H 2 . III -Reaction of H atoms: (1) reactions and trapping processes of hot H atoms have been shown in solid methane and argon by use of hot H atoms with specified initial energy; (2) when H atoms are produced by the radiolysis of solvent alkane or by the photolysis of HI in the alkane mixtures at 77 K, the H atoms react very selectively with solute alkane at low concentration. The selective reaction of the H atom has been found in eight matrices; (3) activation energy for a hydrogen-atom-abstraction reaction by thermal H atoms at low temperatures is less than than several kJ mol -1 because of quantum tunneling. The absolute rate constants for H 2 (D 2 , HD) + H(D) tunneling reactions have been determined experimentally in solid hydrogen at 4.2K; (4) theoretical studies for tunneling reactions H 2 (D 2 ,HD) + H(D) at ultralow temperatures were reviewed. The calculated rate constants were compared with the rate constants obtained experimentally. (author)

  7. Thermal rate coefficients in collinear versus bent transition state reactions: the N+N{sub 2} case study

    Energy Technology Data Exchange (ETDEWEB)

    Lagana, Antonio; Faginas Lago, Noelia; Rampino, Sergio [Dipartimento di Chimica, Universita di Perugia, 06123 Perugia (Italy); Huarte-Larranaga, FermIn [Computer Simulation and Modeling Lab (CoSMoLab), Parc CientIfic de Barcelona, 08028 Barcelona (Spain); GarcIa, Ernesto [Departamento de Quimica Fisica, Universidad del PaIs Vasco, 01006 Vitoria (Spain)], E-mail: lagana05@gmail.com, E-mail: fhuarte@pcb.ub.es, E-mail: e.garcia@ehu.es

    2008-10-15

    Zero total angular momentum exact quantum calculations of the probabilities of the N+N{sub 2} reaction have been performed on the L3 potential energy surface having a bent transition state. This has allowed us to work out J-shifting estimates of the thermal rate coefficient based on the calculation of either detailed (state-to-state) or cumulative (multiconfiguration) probabilities. The results obtained are used to compare the numerical outcomes and the concurrent computational machineries of both quantum and semiclassical approaches as well as to exploit the potentialities of the J-shifting model. The implications of moving the barrier to reaction from the previously proposed collinear geometry of the LEPS to the bent one of L3 are also investigated by comparing the related detailed reactive probabilities.

  8. Reversible bulk-phase change of anthroyl compounds for photopatterning based on photodimerization in the molten state and thermal back reaction.

    Science.gov (United States)

    Kihara, Hideyuki; Yoshida, Masaru

    2013-04-10

    As new organic materials for rewritable photopatterning, 2-anthroyl and 9-anthroyl ester compounds were synthesized. Their bulk-phase changes (we use "bulk-phase change" as complete phase change in a mass of a material neither in a surface nor in a small quantity in this study) triggered by photodimerization under melting conditions (melt-photodimerization) and subsequent thermal back reactions were investigated. All the anthroyl compounds exhibited melting points lower than ca. 160 °C, and they were nearly quantitatively converted to the corresponding photodimers by UV irradiation at temperatures of ∼5 °C higher than their respective melting points. We found that there were two kinds of bulk-phase change behaviors through the photoreaction. Two of the anthroyl compounds remained isotropic and lost fluidity during the melt-photodimerization. The obtained photodimers exhibited robust solid-state amorphous phases at room temperature. In contrast, the other three anthroyl compounds showed crystallization during the melt-photodimerization. The resulting photodimers changed from isotropic to crystalline phases, even at high temperature. Various experiments revealed that the bulk phase of the photodimers was affected not by the existence of regioisomers but by their fluidity at the photoirradiation temperature. The latter three photodimers retained enough fluidity, reflecting their high molecular mobilities at the photoirradiation temperature at which the isothermal crystallization occurred. The other two products were not able to crystallize due to low fluidity, resulting in amorphous phases. We also found that all the photodimers reverted to the corresponding monomers by thermal back reaction and recovered their initial photochemical and thermal properties. Using these reversible bulk-phase changes of the anthroyl compounds, we successfully demonstrated rewritable photopatterning in not only negative images but also positive ones, based on the optical contrast

  9. Physical Acoustics in the Solid State

    CERN Document Server

    Lüthi, B

    2006-01-01

    Suitable for researchers and graduate students in physics and material science, "Physical Acoustics in the Solid State" reviews the modern aspects in the field, including many experimental results, especially those involving ultrasonics. Practically all fields of solid-state physics are covered: metals, semiconductors, magnetism, superconductivity, different kinds of phase transitions, low-dimensional systems, and the quantum Hall effect. After a review of the relevant experimental techniques and an introduction to the theory of elasticity, emphasizing the symmetry aspects, applications in the various fields of condensed matter physics are presented. Also treated are Brillouin-scattering results and results from thermodynamic investigations, such as thermal expansion and specific heat.

  10. Physical Acoustics in the Solid State

    CERN Document Server

    Lüthi, Bruno

    2007-01-01

    Suitable for researchers and graduate students in physics and material science, "Physical Acoustics in the Solid State" reviews the modern aspects in the field, including many experimental results, especially those involving ultrasonics. Practically all fields of solid-state physics are covered: metals, semiconductors, magnetism, superconductivity, different kinds of phase transitions, low-dimensional systems, and the quantum Hall effect. After a review of the relevant experimental techniques and an introduction to the theory of elasticity, emphasizing the symmetry aspects, applications in the various fields of condensed matter physics are presented. Also treated are Brillouin-scattering results and results from thermodynamic investigations, such as thermal expansion and specific heat.

  11. Thermal diffusivity of samarium-gadolinium zirconate solid solutions

    International Nuclear Information System (INIS)

    Pan, W.; Wan, C.L.; Xu, Q.; Wang, J.D.; Qu, Z.X.

    2007-01-01

    We synthesized samarium-gadolinium zirconate solid solutions and determined their thermal diffusivities, Young's moduli and thermal expansion coefficients, which are very important for their application in thermal barrier coatings. Samarium-gadolinium zirconate solid solutions have extremely low thermal diffusivity between 20 and 600 deg. C. The solid solutions have lower Young's moduli and higher thermal expansion coefficients than those of pure samarium and gadolinium zirconates. This combination of characteristics is promising for the application of samarium and gadolinium zirconates in gas turbines. The mechanism of phonon scattering by point defects is discussed

  12. Solid state multinuclear NMR. A versatile tool for studying the reactivity of solid systems

    Energy Technology Data Exchange (ETDEWEB)

    MacKenzie, Kenneth J.D. [MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, P.O. Box 600, Wellington (New Zealand)

    2004-08-31

    Traditionally, X-ray powder diffraction has been a favoured method for studying chemical reactions in the solid state, but the increasing importance of energy-efficient synthesis methods for solids (e.g. sol-gel synthesis, mechanochemical synthesis) has led to the need for an analytical method not dependent on long-range structural periodicity. Multinuclear solid state nuclear magnetic resonance (NMR) represents a technique which is equally applicable to amorphous or crystalline solids, and is now used in increasing numbers of solid state studies.This paper briefly outlines the principles and practical details of this powerful technique and gives examples of its use in solid-state chemistry, particularly in very recent studies of mechanochemical synthesis of advanced sialon ceramics. The temperature at which these technically important silicon aluminium oxynitride compounds are formed can be significantly lowered by high-energy grinding of their components to produce X-ray amorphous precursors. Solid-state NMR has been used to provide detailed information which could not have been obtained by any other means about the chemical environment of the Si and Al atoms in these amorphous precursors, and the various atomic movements undergone as they crystallise to the final product.

  13. Thermally multiplexed polymerase chain reaction.

    Science.gov (United States)

    Phaneuf, Christopher R; Pak, Nikita; Saunders, D Curtis; Holst, Gregory L; Birjiniuk, Joav; Nagpal, Nikita; Culpepper, Stephen; Popler, Emily; Shane, Andi L; Jerris, Robert; Forest, Craig R

    2015-07-01

    Amplification of multiple unique genetic targets using the polymerase chain reaction (PCR) is commonly required in molecular biology laboratories. Such reactions are typically performed either serially or by multiplex PCR. Serial reactions are time consuming, and multiplex PCR, while powerful and widely used, can be prone to amplification bias, PCR drift, and primer-primer interactions. We present a new thermocycling method, termed thermal multiplexing, in which a single heat source is uniformly distributed and selectively modulated for independent temperature control of an array of PCR reactions. Thermal multiplexing allows amplification of multiple targets simultaneously-each reaction segregated and performed at optimal conditions. We demonstrate the method using a microfluidic system consisting of an infrared laser thermocycler, a polymer microchip featuring 1 μl, oil-encapsulated reactions, and closed-loop pulse-width modulation control. Heat transfer modeling is used to characterize thermal performance limitations of the system. We validate the model and perform two reactions simultaneously with widely varying annealing temperatures (48 °C and 68 °C), demonstrating excellent amplification. In addition, to demonstrate microfluidic infrared PCR using clinical specimens, we successfully amplified and detected both influenza A and B from human nasopharyngeal swabs. Thermal multiplexing is scalable and applicable to challenges such as pathogen detection where patients presenting non-specific symptoms need to be efficiently screened across a viral or bacterial panel.

  14. Effect of the reaction medium on the properties of solid catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Boreskov, G.K.

    1980-01-01

    The effect of the reaction medium on the properties of solid catalysts, such as bulk or supported metals, alloys, or metal oxides, include variations in surface composition, structure, and catalytic properties due to catalyst interaction with the reactants. This interaction leads to the establishment of a steady state, which is determined by the composition of the reaction medium and temperature, but is independent of the initial state of the catalyst. This steady state for a catalyst of a given chemical composition is characterized by an approximately constant specific activity in most chemical reactions, which is almost independent of the preparation method, surface area, or crystal size of the catalyst. The structurally sensitive reactions, which occur only on limited segments of catalyst surface characterized by specific structures, are the exception. The effects of the variations in catalytic properties caused by the reaction medium on the steady-state and nonsteady-state reaction kinetics are also discussed based on the results obtained for oxidative dehydrogenation of 1-butene over an iron/antimony oxide catalyst.

  15. Accurate and approximate thermal rate constants for polyatomic chemical reactions

    International Nuclear Information System (INIS)

    Nyman, Gunnar

    2007-01-01

    In favourable cases it is possible to calculate thermal rate constants for polyatomic reactions to high accuracy from first principles. Here, we discuss the use of flux correlation functions combined with the multi-configurational time-dependent Hartree (MCTDH) approach to efficiently calculate cumulative reaction probabilities and thermal rate constants for polyatomic chemical reactions. Three isotopic variants of the H 2 + CH 3 → CH 4 + H reaction are used to illustrate the theory. There is good agreement with experimental results although the experimental rates generally are larger than the calculated ones, which are believed to be at least as accurate as the experimental rates. Approximations allowing evaluation of the thermal rate constant above 400 K are treated. It is also noted that for the treated reactions, transition state theory (TST) gives accurate rate constants above 500 K. TST theory also gives accurate results for kinetic isotope effects in cases where the mass of the transfered atom is unchanged. Due to neglect of tunnelling, TST however fails below 400 K if the mass of the transferred atom changes between the isotopic reactions

  16. Thermal Effects Induced by Laser Irradiation of Solids

    International Nuclear Information System (INIS)

    Galovic, S.

    2004-01-01

    A part of incident energy is absorbed within the irradiated sample when a solid is exposed to the influence of laser radiation, to more general electromagnetic radiation within the wide range of wavelengths (from microwaves, to infrared radiation to X-rays), or to the energy of particle beams (electronic, protonic, or ionic). The absorption process signifies a highly selective excitation of the electronic state of atoms or molecules, followed by thermal and non-thermal de-excitation processes. Non-radiation de-excitation-relaxation processes induce direct sample heating. In addition, a great number of non-thermal processes (e.g., photoluminescence, photochemistry, photovoltage) may also induce heat generation as a secondary process. This method of producing heat is called the photothermal effect.The photothermal effect and subsequent propagation of thermal waves on the surface and in the volume of the solid absorbing the exciting beam may produce the following: variations in the temperature on the surfaces of the sample; deformation and displacement of surfaces; secondary infrared radiation (photothermal radiation); the formation of the gradient of the refractivity index; changes in coefficients of reflection and absorbtion; the generation of sound (photoacoustic generation), etc. These phenomena may be used in the investigation and measurement of various material properties since the profile and magnitude of the generated signal depend upon the nature of material absorbing radiation. A series of non-destructive spectroscopic, microscopic and defectoscopic detecting techniques, called photothermal methods, is developed on the basis of the above-mentioned phenomena.This paper outlines the interaction between the intensity modulated laser beam and solids, and presents a mathematical model of generated thermal sources. Generalized models for a photothermal response of optically excited materials have been obtained, including thermal memory influence on the propagation

  17. Hybrid perovskite resulting from the solid-state reaction between the organic cations and perovskite layers of alpha1-(Br-(CH(2))(2)-NH(3))(2)PbI(4).

    Science.gov (United States)

    Sourisseau, Sebastien; Louvain, Nicolas; Bi, Wenhua; Mercier, Nicolas; Rondeau, David; Buzaré, Jean-Yves; Legein, Christophe

    2007-07-23

    The alpha1-(Br-(CH(2))(2)-NH(3))(2)PbI(4) hybrid perovskite undergoes a solid-state transformation, that is, the reaction between the organic cations and the perovskite layers to give the new hybrid perovskite (Br-(CH(2))(2)-NH(3))(2-x)(I-(CH(2))(2)-NH(3))(x)PbBr(x)I(4-x), based on mixed halide inorganic layers. This transformation has been followed by a conventional powder X-ray diffraction system equipped with a super speed detector, and both solid-state (13)C NMR and ESI/MS measurements have been adopted in the estimation of the rate of halide substitution. The first reaction step leads to the special composition of x approximately 1 (A phase), while the complete substitution is not achieved even at elevated temperature (x(max) approximately 1.85 (B phase)). This unprecedented solid-state reaction between organic and inorganic components of a hybrid perovskite can be considered as a completely new strategy to achieve interesting hybrid perovskites.

  18. Curing reactions of bismaleimide resins catalyzed by triphenylphosphine. High resolution solid-state 13C NMR study

    International Nuclear Information System (INIS)

    Shibahara, Sumio; Enoki, Takashi; Yamamoto, Takahisa; Motoyoshiya, Jiro; Hayashi, Sadao.

    1996-01-01

    The curing reactions of bismaleimide resins consisted of N,N'-4,4'-diphenylmethanebismaleimide (BMI) and o,o'-diallylbisphenol-A (DABA) in the presence of triphenylphosphine (TPP) as a catalyst were investigated. DSC measurements showed that the catalytic effect of TPP on the curing reaction of BMI was more in the presence of DABA than in its absence. In order to explore this curing reaction, N-phenylmaleimide (PMI) and o-allylphenol (AP) were selected as model compounds. The products of the PMI/TPP system were oligomers and polymers of PMI, whereas the main product of the PMI/AP/TPP system was the PMI trimer which had the five-membered ring formed via the phosphonium ylide intermediate. In these model reactions, 13 C NMR was found to be useful to distinguish between trimerization and polymerization of PMI. On the basis of the results of the model reactions, the curing reactions of bismaleimide resins were investigated by high resolution solid state 13 C NMR techniques. In the BMI/TPP system, maleimides polymerize above 175degC, but the polymerization does not proceed at 120degC. On the other hand, maleimides trimerize above 120degC in the presence of DABA and TPP. The mechanism of the trimerization is briefly discussed. (author)

  19. Solid state reaction studies in Fe3O4–TiO2 system by diffusion couple method

    International Nuclear Information System (INIS)

    Ren, Zhongshan; Hu, Xiaojun; Xue, Xiangxin; Chou, Kuochih

    2013-01-01

    Highlights: •The solid state reactions of Fe2O3-TiO2 system was studied by the diffusion couple method. •Different products were formed by diffusion, and the FeTiO3 was more stable phase. •The inter-diffusion coefficients and diffusion activation energy were estimated. -- Abstract: The solid state reactions in Fe 3 O 4 –TiO 2 system has been studied by diffusion couple experiments at 1323–1473 K, in which the oxygen partial pressure was controlled by the CO–CO 2 gas mixture. The XRD analysis was used to confirm the phases of the inter-compound, and the concentration profiles were determined by electron probe microanalysis (EPMA). Based on the concentration profile of Ti, the inter-diffusion coefficients in Fe 3 O 4 phase, which were both temperature and concentration of Ti ions dependent, were calculated by the modified Boltzmann–Matano method. According to the relation between the thickness of diffusion layer and temperature, the diffusion coefficient of the Fe 3 O 4 –TiO 2 system was obtained. According to the Arrhenius equation, the estimated diffusion activation energy was about 282.1 ± 18.8 kJ mol −1

  20. Low-temperature (75 °C) solid-state reaction enhanced by less-crystallized nanoporous PbI2 films for efficient CH3NH3PbI3 perovskite solar cells

    International Nuclear Information System (INIS)

    Zheng, Huifeng; Liu, Yangqiao; Sun, Jing

    2017-01-01

    Highlights: • Efficient perovskite solar cells were prepared with solid-state reaction at 75 °C. • Ln-PbI 2 is superior to c-PbI 2 when applied in low-temperature solid-state reaction. • A higher champion PCE was obtained at 75 °C (13.8%) than that of 140 °C (11.8%). • Non-radiative defects increase significantly when annealed at high temperature. - Abstract: Organohalide perovskite films are usually prepared with the solid-state reaction at a high temperature ≥100 °C, which causes the increase of non-radiative defects and decomposition of perovskite films. Here, we demonstrate it’s feasible to prepare high-quality perovskite films with the solid-state reaction method even at a temperature of 75 °C, when enhanced by less-crystallized nanoporous PbI 2 (ln-PbI 2 ) films. The replacement of compact PbI 2 (c-PbI 2 ) by ln-PbI 2 , results in a significant improvement of crystallinity of perovskite films, besides the elimination of remnant PbI 2 . As a result, ln-PbI 2 based perovskite solar cells display much higher power conversion efficiency (PCE) and better stability. Moreover, annealing duration was found to be critical for high PCE and was optimized as 60 min. Finally, with the optimal process, the champion device displayed a PCE of 13.8% and the average PCE reached 10.1% with a satisfactory deviation. Furthermore, we found annealing at high temperature (140 °C) led to a lower PCE compared with that annealed at 75 °C, because non-radiative defects increased significantly during high-temperature annealing. This work may open up a promising avenue for preparing high-quality perovskite films with the low-temperature solid-state reaction method, which is desirable for real application.

  1. Thermal Conductivity of Carbon Nanotubes Embedded in Solids

    Institute of Scientific and Technical Information of China (English)

    CAO Bing-Yang; HOU Quan-Wen

    2008-01-01

    @@ A carbon-nanotube-atom fixed and activated scheme of non-equilibrium molecular dynamics simulations is put forward to extract the thermal conductivity of carbon nanotubes (CNTs) embedded in solid argon. Though a 6.5% volume fraction of CNTs increases the composite thermal conductivity to about twice as much as that of the pure basal material, the thermal conductivity of CNTs embedded in solids is found to be decreased by 1/8-1/5with reference to that of pure ones. The decrease of the intrinsic thermal conductivity of the solid-embedded CNTs and the thermal interface resistance are demonstrated to be responsible for the results.

  2. Benchmark calculations of thermal reaction rates. I - Quantal scattering theory

    Science.gov (United States)

    Chatfield, David C.; Truhlar, Donald G.; Schwenke, David W.

    1991-01-01

    The thermal rate coefficient for the prototype reaction H + H2 yields H2 + H with zero total angular momentum is calculated by summing, averaging, and numerically integrating state-to-state reaction probabilities calculated by time-independent quantum-mechanical scattering theory. The results are very carefully converged with respect to all numerical parameters in order to provide high-precision benchmark results for confirming the accuracy of new methods and testing their efficiency.

  3. 29Si solid state NMR investigation of pozzolanic reaction occurring in lime-treated Ca-bentonite

    International Nuclear Information System (INIS)

    Pomakhina, Elena; Deneele, Dimitri; Gaillot, Anne-Claire; Paris, Michael; Ouvrard, Guy

    2012-01-01

    Lime is widely used as additive to improve the mechanical properties of natural soil used in earthworks. However, the physico-chemical mechanisms involved are yet not well understood. In order to develop and optimize this treatment method, a better understanding of the interaction between lime and the minerals of the soils, in particular clay minerals, is required. In this study, Ca-bentonite was treated with 2, 5 and 10 wt.% of lime during 1 to 98 days. Modifications in the Si local environment were then monitored by solid state nuclear magnetic resonance to investigate the pozzolanic reaction. All the soil mineral phases contribute to the release of Si and to the pozzolanic reaction, with a rapid and total consumption of Si-polymorph and an exacerbated dissolution of montmorillonite. Mechanism of C–S–H formation, function of the Ca content in the system, was found to match the sorosilicate-tobermorite model described in cement systems.

  4. Growing large columnar grains of CH3NH3PbI3 using the solid-state reaction method enhanced by less-crystallized nanoporous PbI2 films

    Science.gov (United States)

    Zheng, Huifeng; Wang, Weiqi; Liu, Yangqiao; Sun, Jing

    2017-03-01

    Compact, pinhole-free and PbI2-free perovskite films, are desirable for high-performance perovskite solar cells (PSCs), especially if large columnar grains are obtained in which the adverse effects of grain boundaries will be minimized. However, the conventional solid-state reaction methods, originated from the two-step method, failed to grow columnar grains of CH3NH3PbI3 in a facile way. Here, we demonstrate a strategy for growing large columnar grains of CH3NH3PbI3, by less-crystallized nanoporous PbI2 (ln-PbI2) film enhanced solid-state reaction method. We demonstrated columnar grains were obtainable only when ln-PbI2 films were applied. Therefore, the replacement of compact PbI2 by ln-PbI2 in the solid-sate reaction, leads to higher power conversion efficiency, better reproducibility, better stability and less hysteresis. Furthermore, by systematically investigating the effects of annealing temperature and duration, we found that an annealing temperature ≥120 °C was also critical for growing columnar grains. With the optimal process, a champion efficiency of 16.4% was obtained and the average efficiency reached 14.2%. Finally, the mechanism of growing columnar grains was investigated, in which a VPb″ -assisted hooping model was proposed. This work reveals the origins of grain growth in the solid-state reaction method, which will contribute to preparing high quality perovskite films with much larger columnar grains.

  5. High average power solid state laser power conditioning system

    International Nuclear Information System (INIS)

    Steinkraus, R.F.

    1987-01-01

    The power conditioning system for the High Average Power Laser program at Lawrence Livermore National Laboratory (LLNL) is described. The system has been operational for two years. It is high voltage, high power, fault protected, and solid state. The power conditioning system drives flashlamps that pump solid state lasers. Flashlamps are driven by silicon control rectifier (SCR) switched, resonant charged, (LC) discharge pulse forming networks (PFNs). The system uses fiber optics for control and diagnostics. Energy and thermal diagnostics are monitored by computers

  6. Solid State Formation Mechanism of Li4Ti5O12 from an Anatase TiO2 Source

    DEFF Research Database (Denmark)

    Shen, Yanbin; Søndergaard, Martin; Christensen, Mogens

    2014-01-01

    Solid state synthesis of Li4Ti5O12 anode material for Li ion batteries typically results in products containing rutile TiO2 and Li2TiO3 impurities, and subsequent high calcination temperatures lead to particle growth that reduces capacity and rate ability. Here, the formation and growth of Li4Ti5O......12 particles by a solid-state reaction using anatase TiO2 with various crystallite sizes and Li2CO3 is investigated by in situ high temperature powder X-ray diffraction (HT-PXRD) and thermal gravimetry-differential thermal analysis (TG-DTA). The combined data provide insight into the origin...... crystallite sizes (∼50 nm, ∼30 nm, ∼20 nm, and amorphous) were explored, and decreasing crystallite sizes causes a reduced initial reaction temperature. Using anatase with a crystallite size of ∼20 nm resulted in phase pure Li4Ti5O12 at the lowest temperature (800 °C). PXRD and TG-DTA results also revealed...

  7. Chemical and thermal stability of core-shelled magnetite nanoparticles and solid silica

    Science.gov (United States)

    Cendrowski, Krzysztof; Sikora, Pawel; Zielinska, Beata; Horszczaruk, Elzbieta; Mijowska, Ewa

    2017-06-01

    Pristine nanoparticles of magnetite were coated by solid silica shell forming core/shell structure. 20 nm thick silica coating significantly enhanced the chemical and thermal stability of the iron oxide. Chemical and thermal stability of this structure has been compared to the magnetite coated by mesoporous shell and pristine magnetite nanoparticles. It is assumed that six-membered silica rings in a solid silica shell limit the rate of oxygen diffusion during thermal treatment in air and prevent the access of HCl molecules to the core during chemical etching. Therefore, the core/shell structure with a solid shell requires a longer time to induce the oxidation of iron oxide to a higher oxidation state and, basically, even strong concentrated acid such as HCl is not able to dissolve it totally in one month. This leads to the desired performance of the material in potential applications such as catalysis and environmental protection.

  8. IFE Power Plant design principles. Drivers. Solid state laser drivers

    International Nuclear Information System (INIS)

    Nakai, S.; Andre, M.; Krupke, W.F.; Mak, A.A.; Soures, J.M.; Yamanaka, M.

    1995-01-01

    The present status of solid state laser drivers for an inertial confinement thermonuclear fusion power plant is discussed. In particular, the feasibility of laser diode pumped solid state laser drivers from both the technical and economic points of view is briefly reviewed. Conceptual design studies showed that they can, in principle, satisfy the design requirements. However, development of new solid state materials with long fluorescence lifetimes and good thermal characteristics is a key issue for laser diode pumped solid state lasers. With the advent of laser diode pumping many materials which were abandoned in the past can presently be reconsidered as viable candidates. It is also concluded that it is important to examine the technical requirements for solid state lasers in relation to target performance criteria. The progress of laser diode pumped lasers in industrial applications should also be closely watched to provide additional information on the economic feasibility of this type of driver. 15 refs, 9 figs, 2 tabs

  9. Solid state physics

    CERN Document Server

    Burns, Gerald

    2013-01-01

    Solid State Physics, International Edition covers the fundamentals and the advanced concepts of solid state physics. The book is comprised of 18 chapters that tackle a specific aspect of solid state physics. Chapters 1 to 3 discuss the symmetry aspects of crystalline solids, while Chapter 4 covers the application of X-rays in solid state science. Chapter 5 deals with the anisotropic character of crystals. Chapters 6 to 8 talk about the five common types of bonding in solids, while Chapters 9 and 10 cover the free electron theory and band theory. Chapters 11 and 12 discuss the effects of moveme

  10. The Pictet-Spengler reaction in solid-phase combinatorial chemistry

    DEFF Research Database (Denmark)

    Nielsen, Thomas E; Diness, Frederik; Meldal, Morten

    2003-01-01

    The Pictet-Spengler reaction is an important reaction for the generation of tetrahydro-beta-carbolines and tetrahydroisoquinoline ring systems, which exhibit a range of biological and pharmacological properties. This review covers the solid-phase Pictet-Spengler reaction, as employed in solid...

  11. Structural and dynamic properties of solid state ionics

    International Nuclear Information System (INIS)

    Sakuma, T.

    1995-01-01

    The structural and dynamic properties of solid state ionics are reviewed. The low temperature phase transition of the copper halide-chalcogen compounds by specific heat measurements, electrical conductivity measurements and x-ray diffraction measurements are explained. The structures of solid state ionics investigated by the usual x-ray diffraction method and the anomalous x-ray scattering (AXS) measurement are discussed. The expression of the diffuse scattering intensity including the correlations among the thermal displacements of atoms has been given and applied to α-AgI type solid state ionics and lithium sulphate. The presence of low-energy excitations in crystalline copper ion conductors and the superionic conducting glass is investigated by neutron inelastic scattering measurements. The relation between the excitation energy and the mass of the cations is discussed. (author). 141 refs., 21 figs., 7 tabs

  12. Formation of barium strontium titanate powder by solid state reaction using different calcination temperatures

    International Nuclear Information System (INIS)

    Teoh Wah Tzu; Ahmad Fauzi Mohd Noor; Zainal Arifin Ahmad

    2002-01-01

    The unique electrical properties of large permittivity in Barium Strontium Titanate have been widely used to make capacitors; it can be produced by solid state reaction. In this study, the mixture of Barium Carbonate, Strontium Carbonate and Titanium Dioxide was calcined at 500 degree C, 1000 degree C, 1100 degree C , 1150 degree C, 1200 degree C, 1250 degree C and 1300 degree C. The results of the phases change in each stage were investigated via X ay Diffraction. The results show that the formation of Barium Strontium Titanate started at 1100 degree C with the presence of other phases. The mixture is fully reacted to form Barium Strontium Titanate at 1150 degree C. Only Barium Strontium Titanate was formed as the calcination temperature was set higher. (Author)

  13. Solid-State Synthesis and Effect of Temperature on Optical Properties of CuO Nanoparticles

    Institute of Scientific and Technical Information of China (English)

    C.C.Vidyasagar; Y.Arthoba Naik; T.G.Venkatesha; R.Viswanatha

    2012-01-01

    Modulation of band energies through size control offers new ways to control photoresponse and photoconversion efficiency of the solar cell. The P-type semiconductor of copper oxide is an important functional material used for photovoltaic cells. Cu O is attractive as a selective solar absorber since it has high solar absorbance and a low thermal emittance. The present work describes the synthesis and characterization of semiconducting Cu O nanoparticles via one-step, solid-state reaction in the presence of Polyethylene glycol400 as size controlling agent for the preparation of Cu O nanoparticles at different temperatures. Solid-state mechanochemical processing, which is not only a physical size reduction process in conventional milling but also a chemical reaction, is mechanically activated at the nanoscale during grinding. The present method is a simple and efficient method of preparing nanoparticles with high yield at low cost. The structural and chemical composition of the nanoparticles were analyzed by X-ray diffraction, field emission scanning electron microscopy and energy-dispersive spectrometer, respectively. Optical properties and band gap of Cu O nanoparticles were studied by UV-Vis spectroscopy. These results showed that the band gap energy decreased with increase of annealing temperature, which can be attributed to the improvement in grain size of the samples.

  14. In situ57Fe Moessbauer Investigation of Solid-State Redox Reactions of Lithium Insertion Electrodes for Advanced Batteries

    International Nuclear Information System (INIS)

    Sakai, Yoichi; Ariyoshi, Kingo; Ohzuku, Tsutomu

    2002-01-01

    A novel in situ electrochemical cell for 57 Fe Moessbauer measurements was developed in order to clarify the mechanisms of solid-state redox reactions in lithium insertion materials containing iron. Our in situ Moessbauer technique was successfully applied to the determination as to which transition metal ion was a redox center in the insertion electrodes, such as LiFe 0.5 Mn 1.5 O 4 , LiFeTiO 4 , or LiFe 0.25 Ni 0.75 O 2 , for the lithium-ion batteries.

  15. Degradation reactions in SONY-type Li-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Roth, E.P.; Nagasubramanian, G.

    2000-07-01

    Thermal instabilities were identified in SONY-type lithium-ion cells and correlated with interactions of cell constituents and reaction products. Three temperature regions of interaction were identified and associated with the state of charge (degree of Li intercalation) of the cell. Anodes were shown to undergo exothermic reactions as low as 100 C involving the solid electrolyte interface (SEI) layer and the LiPF{sub 6} salt in the electrolyte (EC:PC:DEC/LiPF{sub 6}). These reactions could account for the thermal runaway observed in these cells beginning at 100 C. Exothermic reactions were also observed in the 200 C--300 C region between the intercalated lithium anodes, the LiPF{sub 6} salt, and the PVDF. These reactions were followed by a high-temperature reaction region, 300 C--400 C, also involving the PVDF binder and the intercalated lithium anodes. The solvent was not directly involved in these reactions but served as a moderator and transport medium. Cathode exothermic reactions with the PVDF binder were observed above 200 C and increased with the state of charge (decreasing Li content). This offers an explanation for the observed lower thermal runaway temperatures for charged cells.

  16. Solid-state reaction mechanism and microwave dielectric properties of CaTiO{sub 3}–LaAlO{sub 3} ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Juan [Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Faculty of Materials Science & Engineering, Hubei University, Wuhan 430062 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Hubei University, Wuhan 430062 (China); Fang, Danhua; Lu, Chao; Dou, Zhanming; Wang, Gan; Zhang, Fan [Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Faculty of Materials Science & Engineering, Hubei University, Wuhan 430062 (China); Zhang, Tianjin, E-mail: zhangtj@hubu.edu.cn [Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Faculty of Materials Science & Engineering, Hubei University, Wuhan 430062 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Hubei University, Wuhan 430062 (China)

    2015-07-25

    Highlights: • CaTiO{sub 3}–LaAlO{sub 3} perovskite ceramics were prepared by four sintering reaction routes. • The solid-state reaction mechanism was investigated by XRD and TG/DSC techniques. • Sintering routes had more influence on the parameters of Q × f and τ{sub f} than on ε{sub r}. - Abstract: 0.675CaTiO{sub 3}–0.325LaAlO{sub 3} perovskite ceramics were prepared by a conventional sintering process through four reaction routes. The solid-state reaction mechanisms were investigated by X-ray diffraction and thermogravimetric/differential scanning calorimetric analysis techniques. The results show that interactions occurred between mixtures of CaCO{sub 3} and TiO{sub 2} as well as La{sub 2}O{sub 3} and Al{sub 2}O{sub 3}, and they can influence the sintering behavior of the mixtures. Prior to the formation of solid solutions, the perovskite phases CaTiO{sub 3} and LaAlO{sub 3} were formed regardless of the combination of oxide powders used as reagents. From the powder mixtures which were calcined at 1200 °C, a Ca-rich Ca{sub 9}Al{sub 6}O{sub 18} phase was present at 1400 °C if free La{sub 2}O{sub 3} and Al{sub 2}O{sub 3} used in the reaction mixtures. Ca-rich phases were also formed at higher temperature (1450 °C) if LaAlO{sub 3} was present. The densities of the ceramics obtained by the four routes were different at specific sintering temperatures, and the highest density was obtained for the reaction route two. Results indicated that the preparation pathways had more influence on Q × f and temperature coefficient of the resonant frequency (τ{sub f}) than on the dielectric constants (ε{sub r}), and Q × f decreased and τ{sub f} increased rapidly when the secondary phase presented. Route four is considered as an optimal pathway for the preparation of 0.675CaTiO{sub 3}–0.325LaAlO{sub 3} ceramics.

  17. Energy-saving approaches to solid state street lighting

    Science.gov (United States)

    Vitta, Pranciškus; Stanikūnas, Rytis; Tuzikas, Arūnas; Reklaitis, Ignas; Stonkus, Andrius; Petrulis, Andrius; Vaitkevičius, Henrikas; Žukauskas, Artūras

    2011-10-01

    We consider the energy-saving potential of solid-state street lighting due to improved visual performance, weather sensitive luminance control and tracking of pedestrians and vehicles. A psychophysical experiment on the measurement of reaction time with a decision making task was performed under mesopic levels of illumination provided by a highpressure sodium (HPS) lamp and different solid-state light sources, such as daylight and warm-white phosphor converted light-emitting diodes (LEDs) and red-green-blue LED clusters. The results of the experiment imply that photopic luminances of road surface provided by solid-state light sources with an optimized spectral power distribution might be up to twice as low as those provided by the HPS lamp. Dynamical correction of road luminance against road surface conditions typical of Lithuanian climate was estimated to save about 20% of energy in comparison with constant-level illumination. The estimated energy savings due to the tracking of pedestrians and vehicles amount at least 25% with the cumulative effect of intelligent control of at least 40%. A solid-state street lighting system with intelligent control was demonstrated using a 300 m long test ground consisting of 10 solid-state street luminaires, a meteorological station and microwave motion sensor network operated via power line communication.

  18. The abundant excess heat production during low energy nuclear reaction in the nano scale solid state the cold fusion, 14 years' legacy

    International Nuclear Information System (INIS)

    Woo, Tae Ho; Miley, George H.; Lipson, Andrei; Kim, Sung O.; Luo, Nie; Castano, Carlos H.

    2002-01-01

    The quite abundant excess heat and radioactive materials are found during the solid state reaction. This phenomenon has done during the Low Energy Nuclear Reaction (LENR) in the nano scale molecular structure electrodes and Hydrogen compound electrolytes. The Palladium (or Nickel) and Platinum are incorporated as the electrode and the Light Water (H 2 O) as the electrolyte. The excess heat was produced up to 40% in year 2001. The Alpha particles are also detected. The computer code, Coherent Lattice Accelerator Inter-Ionic Reaction Enhancer (CLAIRE) Code System, is constructed for the simulation. The 0.1 A of the distance between two the Hydrogen ion (proton) and Palladium nucleus is the critical point for the nuclear fusion reaction

  19. Model Experiment of Thermal Runaway Reactions Using the Aluminum-Hydrochloric Acid Reaction

    Science.gov (United States)

    Kitabayashi, Suguru; Nakano, Masayoshi; Nishikawa, Kazuyuki; Koga, Nobuyoshi

    2016-01-01

    A laboratory exercise for the education of students about thermal runaway reactions based on the reaction between aluminum and hydrochloric acid as a model reaction is proposed. In the introductory part of the exercise, the induction period and subsequent thermal runaway behavior are evaluated via a simple observation of hydrogen gas evolution and…

  20. Measurement of the rates of reaction of the ground and metastable excited states of 02+, N0+ and 0+ with atmospheric gases at thermal energy

    International Nuclear Information System (INIS)

    Glosik, J.; Rakshit, A.B.; Twiddy, N.D.; Adams, N.G.; Smith, D.

    1978-01-01

    Thermal-energy reaction rate coefficients and product ion distributions have been measured for reactions of both the ground state and metastable electronic states of 0 2 + , N0 + and 0 + with several neutral species, using a selected-ion flow tube. In general the excited-ion reaction rates are fast, frequently approaching the Langevin limit. Collisional quenching occurs for the reactions of N0 + sup(star) with N 2 ,0 2 and H 2 and the quenching rates have been determined. The ion source also provided a substantial yield of doubly charged 0 2 permitting some measurements of reaction rates of 0 2 2+ . (author)

  1. Electrical and Dielectric Properties of Polyaniline and Polyaniline/Montmorillonite Nanocomposite Prepared by Solid Reaction Using Spectroscopy Impedance

    Directory of Open Access Journals (Sweden)

    Imene Bekri-Abbes

    2015-01-01

    Full Text Available The combination of two components with uniform distribution in nanoscale is expected to facilitate wider applications of the material. In this study, polyaniline (PAn and polyaniline/montmorillonite (Mt nanocomposite were prepared by solid reaction using persulfate of ammonium as oxidant. The phase composition and morphology of the nanocomposite were characterized by FTIR, UV-visible spectroscopy, X-ray diffractometer, thermal gravimetric analysis, and scanning electron microscopy. The electrical and dielectric properties were determined using spectroscopy impedance. The analysis of UV-visible and FTIR spectroscopy demonstrated that aniline chloride has been polymerized into PAn in its conducting emeraldine form. Thermogravimetric analysis suggested that PAn chains intercalated in the clay host are more thermally stable than those of free PAn prepared by solid-solid reaction. Electrical measurements were carried out using the complex impedance technique in the frequency range of 10−2 to 104 Hz at different temperatures. The ac conductivity data of different nanocomposites were analyzed as a function of frequency and temperature. It has been found that the incorporation of inorganic clay phase into polyaniline matrix has an effect on the electrical and dielectric properties of the nanomaterial.

  2. Thermogravimetric analysis and kinetic study of formation of lithium titanate by solid state route

    International Nuclear Information System (INIS)

    Sonak, Sagar; Jain, Uttam; Sahu, Ashok Kumar; Kumar, Sanjay; Krishnamurthy, Nagaiyar

    2015-01-01

    The kinetics of formation of lithium titanate from the solid state reaction of lithium carbonate and titanium oxide was studied using non-isothermal thermogravimetric technique. Thermogravimetric data for the reaction of lithium carbonate and titanium oxide was obtained at various heating rates. The methods such as Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose were used to estimate the kinetic parameters from the obtained thermogravimetric data. The average activation energy for the formation of lithium titanate by solid state route was found to be 243 kJ/mol K. The reaction mechanism was determined by the method given by Malek. It was found that the three dimensional diffusion model best describes the reaction kinetics. A kinetic equation describing the reaction is proposed and reaction mechanism is discussed

  3. Transport processes in exothermic gas-solid reactions

    International Nuclear Information System (INIS)

    Vijay, P.L.; Sathiyamoorthy, D.

    1997-01-01

    The variation of the concentration of gaseous reactant, temperature distribution for an exothermic reaction, the diffusivity factor and the reaction ratio profiles with various radial positions of a solid reactant have been computed and illustrated for a specific case of reduction reaction of UO 3 by hydrogen

  4. Use of labelled atoms in thermal analysis

    International Nuclear Information System (INIS)

    Balek, V.; Beckman, I.N.

    1985-01-01

    The article informs of the preparation of labelled samples for which the most frequently used radionuclides are 14 C, 3 H or 2 H, 32 P, 35 S and others as well as radioactive gases such as 85 Kr, 133 Xe or 220 Rn and 222 Rn. The equipment is described for the application of labelled atoms in thermal analysis consisting of a detector for measuring radioactivity and a system for measuring thermal analysis parameters. Examples are given of the use of labelled atoms in the study of chemical reactions of solids, in autoradiography or in Moessbauer spectroscopy. The greatest attention is devoted to the use of labelled atoms in emanation thermal analysis. By this technique it is possible to study chemical reactions and phase transformations, to continuously monitor changes in the surface and morphology of dispersion substances, to characterize the mobility of defects in the structure of solids and the active state of the structure of solids and to ascertain mechanical, radiation and chemical effects on solids. Attention is also devoted to the technological applications of emanation thermal analysis (the solidification of cement paste, calcination and the firing of the mixture of oxides for the manufacture of ferrites). (E.S.)

  5. The reductive decomposition of calcium sulphate I. Kinetics of the apparent solid-solid reaction

    NARCIS (Netherlands)

    Kamphuis, B.; Potma, A.W.; Prins, W.; van Swaaij, Willibrordus Petrus Maria

    1992-01-01

    The reductive decomposition of calcium sulphate by hydrogen is used for the regeneration of calcium-based atmospheric fluidized bed combustion (AFBC) SO2 sorbents. The apparent solid¿solid reaction between CaS and CaSO4, one of the steps involved in the reaction mechanism of the reductive

  6. Low-temperature (75 °C) solid-state reaction enhanced by less-crystallized nanoporous PbI{sub 2} films for efficient CH{sub 3}NH{sub 3}PbI{sub 3} perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Huifeng [State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China); University of Chinese Academy of Sciences, 19 Yuquan Road, Beijing 100049 (China); Liu, Yangqiao, E-mail: yqliu@mail.sic.ac.cn [State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China); Suzhou Institute of SICCAS (Shanghai Institute of Ceramics, Chinese Academy of Sciences), 238 North Changchun Road, Taicang 215499, Jiangsu Province (China); Sun, Jing, E-mail: jingsun@mail.sic.ac.cn [State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China)

    2017-05-31

    Highlights: • Efficient perovskite solar cells were prepared with solid-state reaction at 75 °C. • Ln-PbI{sub 2} is superior to c-PbI{sub 2} when applied in low-temperature solid-state reaction. • A higher champion PCE was obtained at 75 °C (13.8%) than that of 140 °C (11.8%). • Non-radiative defects increase significantly when annealed at high temperature. - Abstract: Organohalide perovskite films are usually prepared with the solid-state reaction at a high temperature ≥100 °C, which causes the increase of non-radiative defects and decomposition of perovskite films. Here, we demonstrate it’s feasible to prepare high-quality perovskite films with the solid-state reaction method even at a temperature of 75 °C, when enhanced by less-crystallized nanoporous PbI{sub 2} (ln-PbI{sub 2}) films. The replacement of compact PbI{sub 2} (c-PbI{sub 2}) by ln-PbI{sub 2}, results in a significant improvement of crystallinity of perovskite films, besides the elimination of remnant PbI{sub 2}. As a result, ln-PbI{sub 2} based perovskite solar cells display much higher power conversion efficiency (PCE) and better stability. Moreover, annealing duration was found to be critical for high PCE and was optimized as 60 min. Finally, with the optimal process, the champion device displayed a PCE of 13.8% and the average PCE reached 10.1% with a satisfactory deviation. Furthermore, we found annealing at high temperature (140 °C) led to a lower PCE compared with that annealed at 75 °C, because non-radiative defects increased significantly during high-temperature annealing. This work may open up a promising avenue for preparing high-quality perovskite films with the low-temperature solid-state reaction method, which is desirable for real application.

  7. Solid State NMR Characterization of Complex Metal Hydrides systems for Hydrogen Storage Applications

    Directory of Open Access Journals (Sweden)

    Son-Jong Hwang

    2011-12-01

    Full Text Available Solid state NMR is widely applied in studies of solid state chemistries for hydrogen storage reactions. Use of 11B MAS NMR in studies of metal borohydrides (BH4 is mainly focused, revisiting the issue of dodecaborane formation and observation of 11B{1H} Nuclear Overhauser Effect.

  8. Propagation of Reactions in Thermally-damaged PBX-9501

    Energy Technology Data Exchange (ETDEWEB)

    Tringe, J W; Glascoe, E A; Kercher, J R; Willey, T M; Springer, H K; Greenwood, D W; Molitoris, J D; Smilowitz, L; Henson, B F; Maienschein, J L

    2010-03-05

    A thermally-initiated explosion in PBX-9501 (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) is observed in situ by flash x-ray imaging, and modeled with the LLNL multi-physics arbitrary-Lagrangian-Eulerian code ALE3D. The containment vessel deformation provides a useful estimate of the reaction pressure at the time of the explosion, which we calculate to be in the range 0.8-1.4 GPa. Closely-coupled ALE3D simulations of these experiments, utilizing the multi-phase convective burn model, provide detailed predictions of the reacted mass fraction and deflagration front acceleration. During the preinitiation heating phase of these experiments, the solid HMX portion of the PBX-9501 undergoes a {beta}-phase to {delta}-phase transition which damages the explosive and induces porosity. The multi-phase convective burn model results demonstrate that damaged particle size and pressure are critical for predicting reaction speed and violence. In the model, energetic parameters are taken from LLNL's thermochemical-kinetics code Cheetah and burn rate parameters from Son et al. (2000). Model predictions of an accelerating deflagration front are in qualitative agreement with the experimental images assuming a mode particle diameter in the range 300-400 {micro}m. There is uncertainty in the initial porosity caused by thermal damage of PBX-9501 and, thus, the effective surface area for burning. To better understand these structures, we employ x-ray computed tomography (XRCT) to examine the microstructure of PBX-9501 before and after thermal damage. Although lack of contrast between grains and binder prevents the determination of full grain size distribution in this material, there are many domains visible in thermally damaged PBX-9501 with diameters in the 300-400 {micro}m range.

  9. The abundant excess heat production during low energy nuclear reaction in the nano scale solid state the cold fusion, 14 years' legacy

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Tae Ho; Miley, George H.; Lipson, Andrei; Kim, Sung O.; Luo, Nie; Castano, Carlos H. [The University of Illinois, Urbana (United States)

    2002-05-01

    The quite abundant excess heat and radioactive materials are found during the solid state reaction. This phenomenon has done during the Low Energy Nuclear Reaction (LENR) in the nano scale molecular structure electrodes and Hydrogen compound electrolytes. The Palladium (or Nickel) and Platinum are incorporated as the electrode and the Light Water (H{sub 2}O) as the electrolyte. The excess heat was produced up to 40% in year 2001. The Alpha particles are also detected. The computer code, Coherent Lattice Accelerator Inter-Ionic Reaction Enhancer (CLAIRE) Code System, is constructed for the simulation. The 0.1 A of the distance between two the Hydrogen ion (proton) and Palladium nucleus is the critical point for the nuclear fusion reaction.

  10. Studies on the Luminescence Properties of CaZrO3:Eu3+ Phosphors Prepared by the Solid State Reaction Method

    OpenAIRE

    Sahu, Ishwar Prasad; Bisen, D.P.; Tamrakar, R.K.; Murthy, K.V.R.; Mohapatra, M.

    2017-01-01

    CaZrO3:xEu3+ (x = 1.0, 2.0, 3.0, 4.0, and 5.0 mol%) phosphors were successfully prepared by a solid state reaction method. The crystal structure of sintered phosphors was hexagonal phase with space group of Pm-3m. The near ultra-violet (NUV) excitation, emission spectra of the CaZrO3:xEu3+ phosphors were composed of sharp line emission associated with the transitions from the excited states 5D0 to the ground state 7Fj (j = 0, 1, 2, 3, 4) of Eu3+. The results indicated that CaZrO3:xEu3+ might ...

  11. Studies on thermal expansion and XPS of urania-thoria solid solutions

    International Nuclear Information System (INIS)

    Anthonysamy, S.; Panneerselvam, G.; Bera, Santanu; Narasimhan, S.V.; Vasudeva Rao, P.R.

    2000-01-01

    The thermal expansion characteristics of polycrystalline (U y Th 1-y )O 2 solid solutions with y=0.13, 0.55 and 0.91 were determined in the temperature range from 298 to 1973 K by means of X-ray diffraction technique. For these temperatures, the average linear thermal expansion coefficients for (U 0.13 Th 0.87 )O 2 , (U 0.55 Th 0.45 )O 2 and (U 0.91 Th 0.09 )O 2 are 1.033x10 -5 , 1.083x10 -5 and 1.145x10 -5 K -1 , respectively. The measured thermal expansion values were compared with those calculated by applying the equations for linear thermal expansion of pure urania and thoria. It was shown that the stoichiometric (U, Th)O 2 solid solutions are almost ideal at least up to 2000 K. The binding energies of U 4f 7/2 and Th 4f 7/2 electrons of (U 0.1 Th 0.9 )O 2 , (U 0.25 Th 0.75 )O 2 , (U 0.50 Th 0.50 )O 2 , (U 0.75 Th 0.25 )O 2 and (U 0.90 Th 0.10 )O 2 were experimentally determined by X-ray photoelectron spectroscopy. The result showed the presence of only U 4+ and Th 4+ chemical states in the stoichiometric urania-thoria solid solutions

  12. Solid State Division

    International Nuclear Information System (INIS)

    Green, P.H.; Watson, D.M.

    1989-08-01

    This report contains brief discussions on work done in the Solid State Division of Oak Ridge National Laboratory. The topics covered are: Theoretical Solid State Physics; Neutron scattering; Physical properties of materials; The synthesis and characterization of materials; Ion beam and laser processing; and Structure of solids and surfaces

  13. Solar Pumped High Power Solid State Laser for Space Applications

    Science.gov (United States)

    Fork, Richard L.; Laycock, Rustin L.; Green, Jason J. A.; Walker, Wesley W.; Cole, Spencer T.; Frederick, Kevin B.; Phillips, Dane J.

    2004-01-01

    Highly coherent laser light provides a nearly optimal means of transmitting power in space. The simplest most direct means of converting sunlight to coherent laser light is a solar pumped laser oscillator. A key need for broadly useful space solar power is a robust solid state laser oscillator capable of operating efficiently in near Earth space at output powers in the multi hundred kilowatt range. The principal challenges in realizing such solar pumped laser oscillators are: (1) the need to remove heat from the solid state laser material without introducing unacceptable thermal shock, thermal lensing, or thermal stress induced birefringence to a degree that improves on current removal rates by several orders of magnitude and (2) to introduce sunlight at an effective concentration (kW/sq cm of laser cross sectional area) that is several orders of magnitude higher than currently available while tolerating a pointing error of the spacecraft of several degrees. We discuss strategies for addressing these challenges. The need to remove the high densities of heat, e.g., 30 kW/cu cm, while keeping the thermal shock, thermal lensing and thermal stress induced birefringence loss sufficiently low is addressed in terms of a novel use of diamond integrated with the laser material, such as Ti:sapphire in a manner such that the waste heat is removed from the laser medium in an axial direction and in the diamond in a radial direction. We discuss means for concentrating sunlight to an effective areal density of the order of 30 kW/sq cm. The method integrates conventional imaging optics, non-imaging optics and nonlinear optics. In effect we use a method that combines some of the methods of optical pumping solid state materials and optical fiber, but also address laser media having areas sufficiently large, e.g., 1 cm diameter to handle the multi-hundred kilowatt level powers needed for space solar power.

  14. Solid-State Synthesis and Effect of Temp erature on Optical Prop erties of CuO Nanoparticles

    Institute of Scientific and Technical Information of China (English)

    C. C. Vidyasagar; Y. Arthoba Naik∗; T. G. Venkatesha; R. Viswanatha

    2012-01-01

    Modulation of band energies through size control offers new ways to control photoresponse and photoconversion efficiency of the solar cell. The P-type semiconductor of copper oxide is an important functional material used for photovoltaic cells. CuO is attractive as a selective solar absorber since it has high solar absorbance and a low thermal emittance. The present work describes the synthesis and characterization of semiconducting CuO nanoparticles via one-step, solid-state reaction in the presence of Polyethylene glycol 400 as size controlling agent for the preparation of CuO nanoparticles at different temperatures. Solid-state mechanochemical processing, which is not only a physical size reduction process in conventional milling but also a chemical reaction, is mechanically activated at the nanoscale during grinding. The present method is a simple and efficient method of preparing nanoparticles with high yield at low cost. The structural and chemical composition of the nanoparticles were analyzed by X-ray diffraction, field emission scanning electron microscopy and energy-dispersive spectrometer, respectively. Optical properties and band gap of CuO nanoparticles were studied by UV-Vis spectroscopy. These results showed that the band gap energy decreased with increase of annealing temperature, which can be attributed to the improvement in grain size of the samples.

  15. Synthesis and characterization of ZnGa2O4 particles prepared by solid state reaction

    International Nuclear Information System (INIS)

    Can, Musa Mutlu; Hassnain Jaffari, G.; Aksoy, Seda; Shah, S. Ismat; Fırat, Tezer

    2013-01-01

    Highlights: ► Synthesis of ZnGa 2 O 4 particles produced from metallic Zn and Ga particles. ► The structural comparison of spinel and partially inverse spinel structure in ZnGa 2 O 4 . ► The Ga atoms occupied 13% of tetrahedral site in ZnGa 2 O 4 . ► The band gap, calculated from climate point of UV–visible, was found as 4.6 ± 0.1 eV. ► The optical analyses were shown defective ZnO structure in ZnGa 2 O 4 . - Abstract: We employed solid state reaction technique to synthesize ZnGa 2 O 4 particles, produced in steps of mixing/milling the ingredients in H 2 O following thermal treating under 1200 °C. We compare spinel and partially inverse spinel structure in ZnGa 2 O 4 particles using Rietveld refinement. Crystal structure of ZnGa 2 O 4 particles was identified with two structural phases; normal spinel structure and partially inverse spinel structure using Rietveld refinement. It is found that the partially inverse spinel structures occupy nearly 13% and the rest is normal spinel structure. The obtained X-ray diffraction data show that lattice constant and the position of Oxygen atoms remain almost constant in both structures. The characterization of the particles was also improved using X-ray photoelectron spectroscopy and Fourier transforms infrared spectroscopy measurements. The optical analyses were done with UV–visible spectroscopy. The band gap, calculated from climate point of UV–visible data, was found as 4.6 ± 0.1 eV. Despite no unexpected compound (such as ZnO and Ga 2 O 3 ) in the structure, the optical analyses were shown defective ZnO structure in ZnGa 2 O 4 .

  16. Solid State Division

    Energy Technology Data Exchange (ETDEWEB)

    Green, P.H.; Watson, D.M. (eds.)

    1989-08-01

    This report contains brief discussions on work done in the Solid State Division of Oak Ridge National Laboratory. The topics covered are: Theoretical Solid State Physics; Neutron scattering; Physical properties of materials; The synthesis and characterization of materials; Ion beam and laser processing; and Structure of solids and surfaces. (LSP)

  17. Hydrothermal reaction of albite and a sodium aluminosilicate glass: A solid-state NMR study

    Science.gov (United States)

    Yang, Wang-hong Alex; Kirkpatrick, R. James

    1989-04-01

    We present here a solid-state NMR study of the structure and chemical composition of the products and mechanisms of the reaction of crystalline low albite and a glass of nearly albite composition with aqueous solutions of pH from 1 to 11 at 250°C. For the crystalline albite, there are no detectable bulk or surface structural changes due to aqueous attack, consistent with the idea that both cation exchange and disruption of the aluminosilicate framework occur only near the mineral/solution interface and that the hydrated surface layer, if it exists, is not more than about 30 Å thick. This reaction occurs by solution/reprecipitation, and its rate decreases with increasing solution pH, supporting the idea that the dissolution of feldspar is initiated by cation-exchange. For the glass, the reaction proceeds by cation exchange of protons for Na +, incorporation of molecular water into the bulk glass, and a small amount of depolymerization of the aluminosilicate framework in the interior of the glass. Cation exchange becomes less important with increasing solution pH. The incorporation of molecular water and cation-exchange cause structural changes in the glass via solidstate adjustment without dissolution/reprecipitation. The large cations in the hydrated glass (Na and K) probably have a shell of water molecules around them, with a maximum average coordination number of six. The secondary phases formed from both albite and the glass are often amorphous and can be well characterized by NMR. The compositional and structural variations of the amorphous phases are important factors in these reactions and cannot be ignored in theoretical models of aluminosilicate dissolution. As expected, the aluminum coordination in the secondary phases changes from six-fold to four-fold as the solution pH increases.

  18. Advanced kinetics for calorimetric techniques and thermal stability screening of sulfide minerals

    International Nuclear Information System (INIS)

    Iliyas, Abduljelil; Hawboldt, Kelly; Khan, Faisal

    2010-01-01

    Thermal methods of analysis such as differential scanning calorimetry (DSC) provide a powerful methodology for the study of solid reactions. This paper proposes an improved thermal analysis methodology for thermal stability investigation of complex solid-state reactions. The proposed methodology is based on differential iso-conversional approach and involves peak separation, individual peak analysis and combination of isothermal/non-isothermal DSC measurements for kinetic analysis and prediction. The proposed thermal analysis, which coupled with Mineral Libration Analyzer (MLA) technique was employed to investigate thermal behavior of sulfide mineral oxidation. The importance of various experimental variables such as particle size, heating rate and atmosphere were investigated and discussed. The information gained from such an advanced thermal analysis method is useful for scale-up processes with potential of significant savings in plant operations, as well as in mitigating adverse environmental and safety issues arising from handling and storage of sulfide minerals.

  19. Characteristics of rapid-thermal-annealed LiCoO2 cathode film for an all-solid-state thin film microbattery

    International Nuclear Information System (INIS)

    Kim, Han-Ki; Yoon, Young Soo

    2004-01-01

    We report on the fabrication of a LiCoO 2 film for an all-solid-state thin film microbattery by using a rapid-thermal-annealing (RTA) process. The LiCoO 2 films were grown by rf magnetron sputtering using a synthesized LiCoO 2 target in a [O 2 /(Ar+O 2 )] ratio of 10%. Scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES) analysis results showed that the surface layer on the as-deposited LiCoO 2 film was completely removed by rapid thermal annealing process in oxygen ambient for 20 min. In addition, the thin film microbattery fabricated with the annealed LiCoO 2 film shows fairly stable cyclability with a specific discharge capacity of 56.49 μAh/cm2 μm. These results show the possibility of the RTA LiCoO 2 film and rapid thermal annealing process being a promising cathode material and annealing process for thin film microbatteries, respectively

  20. SOLID STATE ENERGY CONVERSION ALLIANCE (SECA) SOLID OXIDE FUEL CELL PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Minh; Jim Powers

    2003-10-01

    This report summarizes the work performed for April 2003--September 2003 reporting period under Cooperative Agreement DE-FC26-01NT41245 for the U.S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid State Energy Conversion Alliance (SECA) Solid oxide Fuel Cell Program''. During this reporting period, the conceptual system design activity was completed. The system design, including strategies for startup, normal operation and shutdown, was defined. Sealant and stack materials for the solid oxide fuel cell (SOFC) stack were identified which are capable of meeting the thermal cycling and degradation requirements. A cell module was tested which achieved a stable performance of 0.238 W/cm{sup 2} at 95% fuel utilization. The external fuel processor design was completed and fabrication begun. Several other advances were made on various aspects of the SOFC system, which are detailed in this report.

  1. Formation of doubly and triply bonded unsaturated compounds HCN, HNC, and CH2NH via N + CH4 low-temperature solid state reaction: from molecular clouds to solar system objects

    Science.gov (United States)

    Mencos, Alejandro; Krim, Lahouari

    2018-06-01

    We show in the current study carried out in solid phase at cryogenic temperatures that methane (CH4) ice exposed to nitrogen atoms is a source of two acids HCN, HNC, and their corresponding hydrogenated unsaturated species CH2NH, in addition to CH3, C2H6, CN-, and three nitrogen hydrides NH, NH2, and NH3. The solid state N + CH4 reaction taken in the ground state seems to be strongly temperature dependent. While at temperatures lower than 10 K only CH3, NH, NH2, and NH3 species formation is promoted due to CH bond dissociation and NH bond formation, stable compounds with CN bonds are formed at temperatures ranged between 10 and 40 K. Many of these reaction products, resulting from CH4 + N reaction, have already been observed in N2-rich regions such as the atmospheres of Titan, Kuiper belt objects, and molecular clouds of the interstellar medium. Our results show the power of the solid state N-atom chemistry in the transformation of simple astrochemical relevant species, such as CH4 molecules and N atoms into complex organic molecules which are also potentially prebiotic species.

  2. Chemical reaction on solid surface observed through isotope tracer technique

    International Nuclear Information System (INIS)

    Tanaka, Ken-ichi

    1983-01-01

    In order to know the role of atoms and ions on solid surfaces as the partners participating in elementary processes, the literatures related to the isomerization and hydrogen exchanging reaction of olefines, the hydrogenation of olefines, the metathesis reaction and homologation of olefines based on solid catalysts were reviewed. Various olefines, of which the hydrogen atoms were substituted with deuterium at desired positions, were reacted using various solid catalysts such as ZnO, K 2 CO 3 on C, MoS 2 (single crystal and powder) and molybdenum oxide (with various carriers), and the infra-red spectra of adsorbed olefines on catalysts, the isotope composition of reaction products and the production rate of the reaction products were measured. From the results, the bonding mode of reactant with the atoms and ions on solid surfaces, and the mechanism of the elementary process were considered. The author emphasized that the mechanism of the chemical reaction on solid surfaces and the role of active points or catalysts can be made clear to the considerable extent by combining isotopes suitably. (Yoshitake, I.)

  3. Solid state reaction studies in Fe{sub 3}O{sub 4}–TiO{sub 2} system by diffusion couple method

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhongshan [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083 (China); School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Hu, Xiaojun, E-mail: huxiaojun@ustb.edu.cn [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083 (China); School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Xue, Xiangxin [School of Materials and Metallurgy, Northeastern University, Shenyang 110006 (China); Chou, Kuochih [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083 (China); School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 (China)

    2013-12-15

    Highlights: •The solid state reactions of Fe2O3-TiO2 system was studied by the diffusion couple method. •Different products were formed by diffusion, and the FeTiO3 was more stable phase. •The inter-diffusion coefficients and diffusion activation energy were estimated. -- Abstract: The solid state reactions in Fe{sub 3}O{sub 4}–TiO{sub 2} system has been studied by diffusion couple experiments at 1323–1473 K, in which the oxygen partial pressure was controlled by the CO–CO{sub 2} gas mixture. The XRD analysis was used to confirm the phases of the inter-compound, and the concentration profiles were determined by electron probe microanalysis (EPMA). Based on the concentration profile of Ti, the inter-diffusion coefficients in Fe{sub 3}O{sub 4} phase, which were both temperature and concentration of Ti ions dependent, were calculated by the modified Boltzmann–Matano method. According to the relation between the thickness of diffusion layer and temperature, the diffusion coefficient of the Fe{sub 3}O{sub 4}–TiO{sub 2} system was obtained. According to the Arrhenius equation, the estimated diffusion activation energy was about 282.1 ± 18.8 kJ mol{sup −1}.

  4. Synthesis of high-purity Li{sub 8}ZrO{sub 6} powder by solid state reaction under hydrogen atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Shin-mura, Kiyoto; Otani, Yu; Ogawa, Seiya [Course of Mechanical Engineering, Graduate School of Engineering, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan); Niwa, Eiki; Hashimoto, Takuya [Department of Physics, College of Humanities and Sciences, Nihon University, 3-8-1 Sakurajousui, Setagaya-ku, Tokyo 156-8550 (Japan); Hoshino, Tsuyoshi [Breeding Functional Materials Development Group, Department of Blanket Systems Research, Rokkasho Fusion Institute, Sector of Fusion Research and Development, Japan Atomic Energy Agency, 2-166 Obuchi, Omotedate, Rokkasho-mura, Kamikita-gun, Aomori 039-3212 (Japan); Sasaki, Kazuya, E-mail: k_sasaki@tokai-u.ac.jp [Course of Mechanical Engineering, Graduate School of Engineering, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan); Department of Prime Mover Engineering, School of Engineering, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan)

    2016-11-01

    Highlights: • A fine pure Li{sub 8}ZrO{sub 6} powder was synthesized by using Li{sub 2}CO{sub 3} and ZrO{sub 2} via a solid state reaction. • Influences on the purity of product powder, lattice defect, and crystal orientation were revealed. • The suitable synthesis conditions of the fine and high purity Li{sub 8}ZrO{sub 6} powder were found. • The reaction process of the synthesis of Li{sub 8}ZrO{sub 6} was estimated. - Abstract: Li{sub 8}ZrO{sub 6} contains a large amount of Li and has a significant potential as a tritium breeder. However, few syntheses of fine-grain, high-purity Li{sub 8}ZrO{sub 6} powder have been reported. In this study, a high-purity powder of Li{sub 8}ZrO{sub 6} was synthesized by solid state reaction under hydrogen atmosphere combined with an effective lithium source and a suitable initial Li:Zr molar ratio. Mixed powders of Li{sub 2}CO{sub 3} and ZrO{sub 2} were fired at around 630 °C in H{sub 2} for several hours and several firing cycles. The low firing temperature inhibited the vaporization of Li during the heating, so that excessive amounts of Li were not needed for the synthesis, and the Li:Zr ratio in the starting material was 10:1 (mol:mol). In this synthesis, Li{sub 2}O was generated via the decomposition of Li{sub 2}CO{sub 3} during firing in H{sub 2}, and reacted with ZrO{sub 2} to form Li{sub 6}Zr{sub 2}O{sub 7}, which reacted with itself to form Li{sub 8}ZrO{sub 6}.

  5. Theoretical solid state physics

    CERN Document Server

    Haug, Albert

    2013-01-01

    Theoretical Solid State Physics, Volume 1 focuses on the study of solid state physics. The volume first takes a look at the basic concepts and structures of solid state physics, including potential energies of solids, concept and classification of solids, and crystal structure. The book then explains single-electron approximation wherein the methods for calculating energy bands; electron in the field of crystal atoms; laws of motion of the electrons in solids; and electron statistics are discussed. The text describes general forms of solutions and relationships, including collective electron i

  6. Thermal properties of paramagnetic solid helium 3

    International Nuclear Information System (INIS)

    Goldstein, L.

    1983-01-01

    It was shown in recent work that over a limited molar volume range and at asymptotically high temperatures the thermal modulations of the pressure along isochores of paramagnetic solid 3 He could be accounted for through the formalism of the Heisenberg model of an antiferromagnetically interacting localized spin- 1/2 system. The internal consistency of this formalism requires the characteristic exchange-interaction parameter of the model derived from pressure modulation data to be identical with that appearing in the other thermal properties of this quantum solid. In a restricted temperature region where the spin excitations are the dominant thermal excitations of the solid, heat capacity data yield exchange-interaction parameters in fair agreement with those derived from pressures along isochores of larger molar volume. At higher temperatures, within well-defined limitations, thermal excitations involve both spin and phononexcitations. Here, because of the opposite temperature variations of the spin and phonon heat capacity components, the ensuing heat capacity minimum determines exactly the exchange-energy parameter and the relevant limiting Debye temperature as a function of the measured temperature location and value of the heat capacity extremum along the experimentally explored isochore. The exchange-energy parameters so derived display larger deviations from their predicted pressure-based values than those resulting from the lower temperature but still asymptotic spin-only heat capacities. At the present time, ambiguities in the experimental determinations of the characteristic Weiss temperatures of the asymptotic paramagnetic susceptibilities prevent one from deriving exchange-energy parameters with them. The present work leads to the prediction, within the limitations of the model formalism, of thermal properties of magnetized solid 3 He

  7. Solid-State Division progress report for period ending March 31, 1983

    International Nuclear Information System (INIS)

    Green, P.H.; Watson, D.M.

    1983-09-01

    Progress and activities are reported on: theoretical solid-state physics (surfaces; electronic, vibrational, and magnetic properties; particle-solid interactions; laser annealing), surface and near-surface properties of solids (surface, plasma-material interactions, ion implantation and ion-beam mixing, pulsed-laser and thermal processing), defects in solids (radiation effects, fracture, impurities and defects, semiconductor physics and photovoltaic conversion), transport properties of solids (fast-ion conductors, superconductivity, mass and charge transport in materials), neutron scattering (small-angle scattering, lattice dynamics, magnetic properties, structure and instrumentation), and preparation and characterization of research materials (growth and preparative methods, nuclear waste forms, special materials)

  8. Solid-State Division progress report for period ending March 31, 1983

    Energy Technology Data Exchange (ETDEWEB)

    Green, P.H.; Watson, D.M. (eds.)

    1983-09-01

    Progress and activities are reported on: theoretical solid-state physics (surfaces; electronic, vibrational, and magnetic properties; particle-solid interactions; laser annealing), surface and near-surface properties of solids (surface, plasma-material interactions, ion implantation and ion-beam mixing, pulsed-laser and thermal processing), defects in solids (radiation effects, fracture, impurities and defects, semiconductor physics and photovoltaic conversion), transport properties of solids (fast-ion conductors, superconductivity, mass and charge transport in materials), neutron scattering (small-angle scattering, lattice dynamics, magnetic properties, structure and instrumentation), and preparation and characterization of research materials (growth and preparative methods, nuclear waste forms, special materials). (DLC)

  9. Porous Organic Nanolayers for Coating of Solid-state Devices

    Science.gov (United States)

    2011-01-01

    Background Highly hydrophobic surfaces can have very low surface energy and such low surface energy biological interfaces can be obtained using fluorinated coatings on surfaces. Deposition of biocompatible organic films on solid-state surfaces is attained with techniques like plasma polymerization, biomineralization and chemical vapor deposition. All these require special equipment or harsh chemicals. This paper presents a simple vapor-phase approach to directly coat solid-state surfaces with biocompatible films without any harsh chemical or plasma treatment. Hydrophilic and hydrophobic monomers were used for reaction and deposition of nanolayer films. The monomers were characterized and showed a very consistent coating of 3D micropore structures. Results The coating showed nano-textured surface morphology which can aid cell growth and provide rich molecular functionalization. The surface properties of the obtained film were regulated by varying monomer concentrations, reaction time and the vacuum pressure in a simple reaction chamber. Films were characterized by contact angle analysis for surface energy and with profilometer to measure the thickness. Fourier Transform Infrared Spectroscopy (FTIR) analysis revealed the chemical composition of the coated films. Variations in the FTIR results with respect to different concentrations of monomers showed the chemical composition of the resulting films. Conclusion The presented approach of vapor-phase coating of solid-state structures is important and applicable in many areas of bio-nano interface development. The exposure of coatings to the solutions of different pH showed the stability of the coatings in chemical surroundings. The organic nanocoating of films can be used in bio-implants and many medical devices. PMID:21569579

  10. Porous Organic Nanolayers for Coating of Solid-state Devices

    Directory of Open Access Journals (Sweden)

    Asghar Waseem

    2011-05-01

    Full Text Available Abstract Background Highly hydrophobic surfaces can have very low surface energy and such low surface energy biological interfaces can be obtained using fluorinated coatings on surfaces. Deposition of biocompatible organic films on solid-state surfaces is attained with techniques like plasma polymerization, biomineralization and chemical vapor deposition. All these require special equipment or harsh chemicals. This paper presents a simple vapor-phase approach to directly coat solid-state surfaces with biocompatible films without any harsh chemical or plasma treatment. Hydrophilic and hydrophobic monomers were used for reaction and deposition of nanolayer films. The monomers were characterized and showed a very consistent coating of 3D micropore structures. Results The coating showed nano-textured surface morphology which can aid cell growth and provide rich molecular functionalization. The surface properties of the obtained film were regulated by varying monomer concentrations, reaction time and the vacuum pressure in a simple reaction chamber. Films were characterized by contact angle analysis for surface energy and with profilometer to measure the thickness. Fourier Transform Infrared Spectroscopy (FTIR analysis revealed the chemical composition of the coated films. Variations in the FTIR results with respect to different concentrations of monomers showed the chemical composition of the resulting films. Conclusion The presented approach of vapor-phase coating of solid-state structures is important and applicable in many areas of bio-nano interface development. The exposure of coatings to the solutions of different pH showed the stability of the coatings in chemical surroundings. The organic nanocoating of films can be used in bio-implants and many medical devices.

  11. Solid-state, ambient-operation thermally activated delayed fluorescence from flexible, non-toxic gold-nanocluster thin films: towards the development of biocompatible light-emitting devices

    Science.gov (United States)

    Talite, M. J. A.; Lin, H. T.; Jiang, Z. C.; Lin, T. N.; Huang, H. Y.; Heredia, E.; Flores, A.; Chao, Y. C.; Shen, J. L.; Lin, C. A. J.; Yuan, C. T.

    2016-08-01

    Luminescent gold nanoclusters (AuNCs) with good biocompatibility have gained much attention in bio-photonics. In addition, they also exhibit a unique photo-physical property, namely thermally activated delayed fluorescence (TADF), by which both singlet and triplet excitons can be harvested. The combination of their non-toxic material property and unique TADF behavior makes AuNCs biocompatible nano-emitters for bio-related light-emitting devices. Unfortunately, the TADF emission is quenched when colloidal AuNCs are transferred to solid states under ambient environment. Here, a facile, low-cost and effective method was used to generate efficient and stable TADF emissions from solid AuNCs under ambient environment using polyvinyl alcohol as a solid matrix. To unravel the underlying mechanism, temperature-dependent static and transient photoluminescence measurements were performed and we found that two factors are crucial for solid TADF emission: small energy splitting between singlet and triplet states and the stabilization of the triplet states. Solid TADF films were also deposited on the flexible plastic substrate with patterned structures, thus mitigating the waveguide-mode losses. In addition, we also demonstrated that warm white light can be generated based on a co-doped single emissive layer, consisting of non-toxic, solution-processed TADF AuNCs and fluorescent carbon dots under UV excitation.

  12. Liquid-like thermal conduction in intercalated layered crystalline solids

    Science.gov (United States)

    Li, B.; Wang, H.; Kawakita, Y.; Zhang, Q.; Feygenson, M.; Yu, H. L.; Wu, D.; Ohara, K.; Kikuchi, T.; Shibata, K.; Yamada, T.; Ning, X. K.; Chen, Y.; He, J. Q.; Vaknin, D.; Wu, R. Q.; Nakajima, K.; Kanatzidis, M. G.

    2018-03-01

    As a generic property, all substances transfer heat through microscopic collisions of constituent particles1. A solid conducts heat through both transverse and longitudinal acoustic phonons, but a liquid employs only longitudinal vibrations2,3. As a result, a solid is usually thermally more conductive than a liquid. In canonical viewpoints, such a difference also serves as the dynamic signature distinguishing a solid from a liquid. Here, we report liquid-like thermal conduction observed in the crystalline AgCrSe2. The transverse acoustic phonons are completely suppressed by the ultrafast dynamic disorder while the longitudinal acoustic phonons are strongly scattered but survive, and are thus responsible for the intrinsically ultralow thermal conductivity. This scenario is applicable to a wide variety of layered compounds with heavy intercalants in the van der Waals gaps, manifesting a broad implication on suppressing thermal conduction. These microscopic insights might reshape the fundamental understanding on thermal transport properties of matter and open up a general opportunity to optimize performances of thermoelectrics.

  13. Influence of cooling modes on purity of solid-state synthesized tetracalcium phosphate

    International Nuclear Information System (INIS)

    Guo Dagang; Xu Kewei; Han Yong

    2005-01-01

    Pure tetracalcium phosphate powder (TTCP) was prepared by a solid-state phase reaction at 1500 deg. C. Effects of cooling modes on the synthesizing process of TTCP powder and its thermal behavior at different heating temperatures were investigated by XRD and FTIR. The results show that cooling in dry air tends to promote formation of single phase TTCP, while in situ cooling in furnace results in a mixture of hydroxyapatite (HAP) and CaO. The examination of the thermal behavior of TTCP indicates that there exists a decomposing zone in the range of 500 deg. C-1200 deg. C, in which the high-temperature synthesized TTCP phase is transformed during the subsequent cooling process. This was confirmed by three additional cooling treatment routes that provide significant experimental evidence to the cooling modes effect on the purity of TTCP. The phase transformation course of starting materials heated to elevated temperatures was further studied by TGA-DSC analysis with the aid of XRD and FTIR, in order to fully understand the complicated synthesizing process of TTCP

  14. Solid state radiation dosimetry

    International Nuclear Information System (INIS)

    Moran, P.R.

    1976-01-01

    Important recent developments provide accurate, sensitive, and reliable radiation measurements by using solid state radiation dosimetry methods. A review of the basic phenomena, devices, practical limitations, and categories of solid state methods is presented. The primary focus is upon the general physics underlying radiation measurements with solid state devices

  15. Luminescence and the solid state

    CERN Document Server

    Ropp, Richard C

    2013-01-01

    Since the discovery of the transistor in 1948, the study of the solid state has been burgeoning. Recently, cold fusion and the ceramic superconductor have given cause for excitement. There are two approaches possible to this area of science, namely, that of solid state physics and solid state chemistry, although both overlap extensively. The former is more concerned with electronic states in solids (including electromagnetics) whereas the latter is more concerned with interactions of atoms in solids. The area of solid state physics is well documented, however, there are very few texts which de

  16. Solid state video cameras

    CERN Document Server

    Cristol, Y

    2013-01-01

    Solid State Video Cameras reviews the state of the art in the field of solid-state television cameras as compiled from patent literature. Organized into 10 chapters, the book begins with the basic array types of solid-state imagers and appropriate read-out circuits and methods. Documents relating to improvement of picture quality, such as spurious signal suppression, uniformity correction, or resolution enhancement, are also cited. The last part considerssolid-state color cameras.

  17. Mechanistic Aspects of the Thermal Decomposition of Dicyclopentadienyl Titanium(IV) Dibenzyl

    NARCIS (Netherlands)

    Boekel, C.P.; Teuben, J.H.; Liefde Meijer, H.J. de

    1975-01-01

    The thermal decomposition of dicyclopentadienyltitanium(IV) dibenzyl in the solid state and in hydrocarbon solvents has been investigated. The compound decomposes via intermolecular abstraction of hydrogen atoms from the cyclopentadienyl rings with quantitative formation of toluene. The reaction was

  18. Risperidone – Solid-state characterization and pharmaceutical compatibility using thermal and non-thermal techniques

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, Josiane Souza Pereira; Veronez, Isabela Pianna; Rodrigues, Larissa Lopes [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil); Trevisan, Marcello G. [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil); National Institute of Bioanalytics Science and Technology – INCTBio, Institute of Chemistry – UNICAMP, 13084-653, Campinas, São Paulo (Brazil); Garcia, Jerusa Simone, E-mail: jerusa.garcia@unifal-mg.edu.br [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil)

    2013-09-20

    Highlights: • DSC was used to characterize Risperidone and study its compatibility with excipients. • FT-IR associated with PCA was used to complement DSC data. • LC analyzes confirmed the DSC and FT-IR/PCA results. • Risperidone was incompatible with three among five excipients evaluated. - Abstract: A full solid-state characterization of risperidone was conducted using differential scanning calorimetry (DSC), thermogravimetry (TG), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) to examine its physicochemical properties and polymorphism. The primary aim of this work was to study the compatibility of risperidone with pharmaceutical excipients using DSC to obtain and compare the curves of the active pharmaceutical ingredient (API) and the excipients with their 1:1 (w/w) binary mixtures. These same binary mixtures were turned to room temperature and analyzed by FT-IR combined with principal component analysis (PCA) to evaluate solid-state incompatibilities. The chemical incompatibilities of these samples were verified using a stability-indicating liquid chromatography (LC) method to assay for the API and evaluate the formation of degradation products. All of these methods showed incompatibilities between risperidone and the excipients magnesium stearate, lactose and cellulose microcrystalline.

  19. Enriched Boron-Doped Amorphous Selenium Based Position-Sensitive Solid-State Thermal Neutron Detector for MPACT Applications

    International Nuclear Information System (INIS)

    Mandal, Krishna

    2017-01-01

    High-efficiency thermal neutron detectors with compact size, low power-rating and high spatial, temporal and energy resolution are essential to execute non-proliferation and safeguard protocols. The demands of such detector are not fully covered by the current detection system such as gas proportional counters or scintillator-photomultiplier tube combinations, which are limited by their detection efficiency, stability of response, speed of operation, and physical size. Furthermore, world-wide shortage of 3 He gas, required for widely used gas detection method, has further prompted to design an alternative system. Therefore, a solid-state neutron detection system without the requirement of 3 He will be very desirable. To address the above technology gap, we had proposed to develop new room temperature solidstate thermal neutron detectors based on enriched boron ( 10 B) and enriched lithium ( 6 Li) doped amorphous Se (As- 0.52%, Cl 5 ppm) semiconductor for MPACT applications. The proposed alloy materials have been identified for its many favorable characteristics - a wide bandgap (~2.2 eV at 300 K) for room temperature operation, high glass transition temperature (t g ~ 85°C), a high thermal neutron cross-section (for boron ~ 3840 barns, for lithium ~ 940 barns, 1 barn = 10 -24 cm 2 ), low effective atomic number of Se for small gamma ray sensitivity, and high radiation tolerance due to its amorphous structure.

  20. A coupled mechanical-chemical model for reflecting the influence of stress on oxidation reactions in thermal barrier coating

    Science.gov (United States)

    Chen, Lin; Yueming, Li

    2018-06-01

    In this paper, a coupled mechanical-chemical model is established based on the thermodynamic framework, in which the contribution of chemical expansion to free energy is introduced. The stress-dependent chemical potential equilibrium at the gas-solid interface and the stress gradient-dependent diffusion equation as well as a so-called generalized force which is conjugate to the oxidation rate are derived from the proposed model, which could reflect the influence of stresses on the oxidation reaction. Based on the proposed coupled mechanical-chemical model, a user element subroutine is developed in ABAQUS. The numerical simulation of the high temperature oxidation in the thermal barrier coating is carried out to verify the accuracy of the proposed model, and then the influence of stresses on the oxidation reaction is investigated. In thermally grown oxide, the considerable stresses would be induced by permanent volumetric swelling during the oxidation. The stresses play an important role in the chemical potential equilibrium at the gas-solid interface and strongly affect the oxidation reaction. The gradient of the stresses, however, only occurs in the extremely thin oxidation front layer, which plays a very limited role in the oxidation reaction. The generalized force could be divided into the stress-dependent and the stress-independent parts. Comparing with the stress-independent part, the stress-dependent part is smaller, which has little influence on oxidation reaction.

  1. Graphite Carbon-Supported Mo2C Nanocomposites by a Single-Step Solid State Reaction for Electrochemical Oxygen Reduction.

    Science.gov (United States)

    Huang, K; Bi, K; Liang, C; Lin, S; Wang, W J; Yang, T Z; Liu, J; Zhang, R; Fan, D Y; Wang, Y G; Lei, M

    2015-01-01

    Novel graphite-molybdenum carbide nanocomposites (G-Mo2C) are synthesized by a typical solid state reaction with melamine and MoO3 as precursors under inert atmosphere. The characterization results indicate that G-Mo2C composites are composed of high crystallization and purity of Mo2C and few layers of graphite carbon. Mo2C nanoparticles with sizes ranging from 5 to 50 nm are uniformly supported by surrounding graphite layers. It is believed that Mo atom resulting from the reduction of MoO3 is beneficial to the immobilization of graphite carbon. Moreover, the electrocatalytic performances of G-Mo2C for ORR in alkaline medium are investigated by cyclic voltammetry (CV), rotating disk electrode (RDE) and chronoamperometry test with 3M methanol. The results show that G-Mo2C has a considerable catalytic activity and superior methanol tolerance performance for the oxygen reduction reaction (ORR) benefiting from the chemical interaction between the carbide nanoparticles and graphite carbon.

  2. Forming a three-dimensional porous organic network via solid-state explosion of organic single crystals.

    Science.gov (United States)

    Bae, Seo-Yoon; Kim, Dongwook; Shin, Dongbin; Mahmood, Javeed; Jeon, In-Yup; Jung, Sun-Min; Shin, Sun-Hee; Kim, Seok-Jin; Park, Noejung; Lah, Myoung Soo; Baek, Jong-Beom

    2017-11-17

    Solid-state reaction of organic molecules holds a considerable advantage over liquid-phase processes in the manufacturing industry. However, the research progress in exploring this benefit is largely staggering, which leaves few liquid-phase systems to work with. Here, we show a synthetic protocol for the formation of a three-dimensional porous organic network via solid-state explosion of organic single crystals. The explosive reaction is realized by the Bergman reaction (cycloaromatization) of three enediyne groups on 2,3,6,7,14,15-hexaethynyl-9,10-dihydro-9,10-[1,2]benzenoanthracene. The origin of the explosion is systematically studied using single-crystal X-ray diffraction and differential scanning calorimetry, along with high-speed camera and density functional theory calculations. The results suggest that the solid-state explosion is triggered by an abrupt change in lattice energy induced by release of primer molecules in the 2,3,6,7,14,15-hexaethynyl-9,10-dihydro-9,10-[1,2]benzenoanthracene crystal lattice.

  3. Alternative materials for solid oxide fuel cells: Factors affecting air-sintering of chromite interconnections

    International Nuclear Information System (INIS)

    Chick, L.A.; Bates, J.L.

    1992-01-01

    The purpose of this research is to develop alternative materials for solid oxide fuel cell (SOFC) interconnections and electrodes with improved electrical, thermal and electrochemical properties. Another objective is to develop synthesis and fabrication processes for these materials whereby they can be consolidated in air into SOFC's. The approach is to (1) develop modifications of the current, state-of-the-art materials used in SOFC's, (2) minimize the number of cations used in the SOFC materials to reduce potential deleterious interactions, (3) improve thermal, electrical, and electrochemical properties, (4) develop methods to synthesize both state-of-the-art and alternative materials for the simultaneous fabrication and consolidation in air of the interconnections and electrodes with the solid electrolyte, and (5) understand electrochemical reactions at materials interfaces and the effects of component compositions and processing on those reactions

  4. Analytical model for the effects of wetting on thermal boundary conductance across solid/classical liquid interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Caplan, Matthew E.; Giri, Ashutosh; Hopkins, Patrick E., E-mail: phopkins@virginia.edu [Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States)

    2014-04-21

    We develop an analytical model for the thermal boundary conductance between a solid and a liquid. By infusing recent developments in the phonon theory of liquid thermodynamics with diffuse mismatch theory, we derive a closed form model that can predict the effects of wetting on the thermal boundary conductance across an interface between a solid and a classical liquid. We account for the complete wetting (hydrophilicity), or lack thereof (hydrophobicity), of the liquid to the solid by considering varying contributions of transverse mode interactions between the solid and liquid interfacial layers; this transverse coupling relationship is determined with local density of states calculations from molecular dynamics simulations between Lennard-Jones solids and a liquids with different interfacial interaction energies. We present example calculations for the thermal boundary conductance between both hydrophobic and hydrophilic interfaces of Al/water and Au/water, which show excellent agreement with measured values reported by Ge et al. [Z. Ge, D. G. Cahill, and P. V. Braun, Phys. Rev. Lett. 96, 186101 (2006)]. Our model does not require any fitting parameters and is appropriate to model heat flow across any planar interface between a solid and a classical liquid.

  5. Contribution to the modelling of gas-solid reactions and reactors; Contribution a la modelisation des reactions et des reacteurs gaz-solide

    Energy Technology Data Exchange (ETDEWEB)

    Patisson, F

    2005-09-15

    Gas-solid reactions control a great number of major industrial processes involving matter transformation. This dissertation aims at showing that mathematical modelling is a useful tool for both understanding phenomena and optimising processes. First, the physical processes associated with a gas-solid reaction are presented in detail for a single particle, together with the corresponding available kinetic grain models. A second part is devoted to the modelling of multiparticle reactors. Different approaches, notably for coupling grain models and reactor models, are illustrated through various case studies: coal pyrolysis in a rotary kiln, production of uranium tetrafluoride in a moving bed furnace, on-grate incineration of municipal solid wastes, thermogravimetric apparatus, nuclear fuel making, steel-making electric arc furnace. (author)

  6. Preparation, characterization and thermal behaviour study of 4-dimethyl amino benzal pyruvate of lanthanides (III) and yttrium (III) in solid state

    International Nuclear Information System (INIS)

    Miyano, M.H.

    1990-01-01

    Solid state compounds involving Ln and DMBP, where Ln trivalent lanthanides (except promethium) and yttrium; DMBP 4-dimethyl amino benzylidene pyruvate, were prepared by addition of ligand to the corresponding metal ions chlorides, both in aqueous solution. The precipitates were washed with distilled water and dried at 40 0 C in a forced circulation oven. Complexometry with EDTA, thermogravimetry (TG), differential thermal analysis (DTA), infra-red absorption and X-ray diffraction have been used in the study of these compounds. (author)

  7. Rechargeable quasi-solid state lithium battery with organic crystalline cathode

    Science.gov (United States)

    Hanyu, Yuki; Honma, Itaru

    2012-01-01

    Utilization of metal-free low-cost high-capacity organic cathodes for lithium batteries has been a long-standing goal, but critical cyclability problems owing to dissolution of active materials into the electrolyte have been an inevitable obstacle. For practical utilisation of numerous cathode-active compounds proposed over the past decades, a novel battery construction strategy is required. We have designed a solid state cell that accommodates organic cathodic reactions in solid phase. The cell was successful at achieving high capacity exceeding 200 mAh/g with excellent cycleability. Further investigations confirmed that our strategy is effective for numerous other redox-active organic compounds. This implies hundreds of compounds dismissed before due to low cycleability would worth a re-visit under solid state design. PMID:22693655

  8. Self-aligned nanocrystalline ZnO hexagons by facile solid-state and co-precipitation route

    International Nuclear Information System (INIS)

    Thorat, J. H.; Kanade, K. G.; Nikam, L. K.; Chaudhari, P. D.; Panmand, R. P.; Kale, B. B.

    2012-01-01

    In this study, we report the synthesis of well-aligned nanocrystalline hexagonal zinc oxide (ZnO) nanoparticles by facile solid-state and co-precipitation method. The co-precipitation reactions were performed using aqueous and ethylene glycol (EG) medium using zinc acetate and adipic acid to obtain zinc adipate and further decomposition at 450 °C to confer nanocrystalline ZnO hexagons. XRD shows the hexagonal wurtzite structure of the ZnO. Thermal study reveals complete formation of ZnO at 430 °C in case of solid-state method, whereas in case of co-precipitation method complete formation was observed at 400 °C. Field emission scanning electron microscope shows spherical morphology for ZnO synthesized by solid-state method. The aqueous-mediated ZnO by co-precipitation method shows rod-like morphology. These rods are formed via self assembling of spherical nanoparticles, however, uniformly dispersed spherical crystallites were seen in EG-mediated ZnO. Transmission electron microscope (TEM) investigations clearly show well aligned and highly crystalline transparent and thin hexagonal ZnO. The particle size was measured using TEM and was observed to be 50–60 nm in case of solid-state method and aqueous-mediated co-precipitation method, while 25–50 nm in case of EG-mediated co-precipitation method. UV absorption spectra showed sharp absorption peaks with a blue shift for EG-mediated ZnO, which demonstrate the mono-dispersed lower particle size. The band gap of the ZnO was observed to be 3.4 eV which is higher than the bulk, implies nanocrystalline nature of the ZnO. The photoluminescence studies clearly indicate the strong violet and weak blue emission in ZnO nanoparticles which is quite unique. The process investigated may be useful to synthesize other oxide semiconductors and transition metal oxides.

  9. Self-aligned nanocrystalline ZnO hexagons by facile solid-state and co-precipitation route

    Energy Technology Data Exchange (ETDEWEB)

    Thorat, J. H. [Mahatma Phule College, Department of Chemistry (India); Kanade, K. G. [Annasaheb Awate College (India); Nikam, L. K. [B.G. College (India); Chaudhari, P. D.; Panmand, R. P.; Kale, B. B., E-mail: kbbb1@yahoo.com [Center for Materials for Electronics Technology (C-MET) (India)

    2012-02-15

    In this study, we report the synthesis of well-aligned nanocrystalline hexagonal zinc oxide (ZnO) nanoparticles by facile solid-state and co-precipitation method. The co-precipitation reactions were performed using aqueous and ethylene glycol (EG) medium using zinc acetate and adipic acid to obtain zinc adipate and further decomposition at 450 Degree-Sign C to confer nanocrystalline ZnO hexagons. XRD shows the hexagonal wurtzite structure of the ZnO. Thermal study reveals complete formation of ZnO at 430 Degree-Sign C in case of solid-state method, whereas in case of co-precipitation method complete formation was observed at 400 Degree-Sign C. Field emission scanning electron microscope shows spherical morphology for ZnO synthesized by solid-state method. The aqueous-mediated ZnO by co-precipitation method shows rod-like morphology. These rods are formed via self assembling of spherical nanoparticles, however, uniformly dispersed spherical crystallites were seen in EG-mediated ZnO. Transmission electron microscope (TEM) investigations clearly show well aligned and highly crystalline transparent and thin hexagonal ZnO. The particle size was measured using TEM and was observed to be 50-60 nm in case of solid-state method and aqueous-mediated co-precipitation method, while 25-50 nm in case of EG-mediated co-precipitation method. UV absorption spectra showed sharp absorption peaks with a blue shift for EG-mediated ZnO, which demonstrate the mono-dispersed lower particle size. The band gap of the ZnO was observed to be 3.4 eV which is higher than the bulk, implies nanocrystalline nature of the ZnO. The photoluminescence studies clearly indicate the strong violet and weak blue emission in ZnO nanoparticles which is quite unique. The process investigated may be useful to synthesize other oxide semiconductors and transition metal oxides.

  10. Nano-sized Li4Ti5O12 anode material with excellent performance prepared by solid state reaction: The effect of precursor size and morphology

    International Nuclear Information System (INIS)

    Li, Xiangru; Hu, Hao; Huang, Sheng; Yu, Gaige; Gao, Lin; Liu, Haowen; Yu, Ying

    2013-01-01

    Graphical abstract: - Highlights: • Nano-sized Li 4 Ti 5 O 12 has been prepared through solid state reaction by using axiolitic TiO 2 as precursor. • The prepared nano-sized Li 4 Ti 5 O 12 anode material shows excellent electrochemical performance. • The utilization of precursor with special morphology and size is one of the useful ways to prepare more active electrode materials. - Abstract: Spinel nano-sized Li 4 Ti 5 O 12 anode material of secondary lithium-ion battery has been successfully prepared by solid state reaction using axiolitic TiO 2 assembled by 10–20 nm nanoparticles and Li 2 CO 3 as precursors. The synthesis condition, grain size effect and corresponding electrochemical performance of the special Li 4 Ti 5 O 12 have been studied in comparison with those of the normal Li 4 Ti 5 O 12 originated from commercial TiO 2 . We also propose the mechanism that using the nano-scaled TiO 2 with special structure and unexcess Li 2 CO 3 as precursors can synthesize pure phase nano-sized Li 4 Ti 5 O 12 at 800 °C through solid state reaction. The prepared nano-sized Li 4 Ti 5 O 12 anode material for Li-ion batteries shows excellent capacity performance with rate capacity of 174.2, 164.0, 157.4, 146.4 and 129.6 mA h g −1 at 0.5, 1, 2, 5 and 10 C, respectively, and capacity retention of 95.1% after 100 cycles at 1 C. In addition, the specific capacity fade for the cell with the different Li 4 Ti 5 O 12 active materials resulted from the increase of internal resistance after 100 cycles is compared

  11. Thermally stimulated exoelectron emission from solid Xe

    International Nuclear Information System (INIS)

    Khyzhniy, I.V.; Grigorashchenko, O.N.; Savchenko, E.V.; Ponomarev, A.N.; Bondybey, V.E.

    2007-01-01

    Thermally-stimulated emission of exoelectrons and photons from solid Xe pre-irradiated by low-energy electrons were studied. A high sensitivity of thermally-stimulated luminescence (TSL) and thermally-stimulated exoelectron emission (TSEE) to sample prehistory was demonstrated. It was shown that electron traps in unannealed samples are characterized by much broader distribution of trap levels in comparison with annealed samples and their concentration exceeds in number that in annealed samples. Both phenomena, TSL and TSEE, were found to be triggered by release of electrons from the same kind of traps. The data obtained suggest a competition between two relaxation channels: charge recombination and electron transport terminated by TSL and TSEE. It was found that TSEE predominates at low temperatures while at higher temperatures TSL prevails. An additional relaxation channel, a photon-stimulated exoelectron emission pre-irradiated solid Xe, was revealed

  12. Emerging applications of spark plasma sintering in all solid-state lithium-ion batteries and beyond

    Science.gov (United States)

    Zhu, Hongzheng; Liu, Jian

    2018-07-01

    Solid-state batteries have received increasing attention due to their high safety aspect and high energy and power densities. However, the development of solid-state batteries is hindered by inferior solid-solid interfaces between the solid-state electrolyte and electrode, which cause high interfacial resistance, reduced Li-ion and electron transfer rate, and limited battery performance. Recently, spark plasma sintering (SPS) is emerging as a promising technique for fabricating solid-state electrolyte and electrode pellets with clean and intimate solid-solid interfaces. During the SPS process, the unique reaction mechanism through the combination of current, pressure and high heating rate allow the formation of desirable solid-solid interfaces between active material particles. Herein, this work focuses on the overview of the application of SPS for fabricating solid-state electrolyte and electrode in all solid-state Li-ion batteries, and beyond, such as solid-state Li-S and Na-ion batteries. The correlations among SPS parameters, interfacial resistance, and electrochemical properties of solid-state electrolytes and electrodes are discussed for different material systems. In the end, we point out future opportunities and challenges associated with SPS application in the hot area of solid-state batteries. It is expected that this timely review will stimulate more fundamental and applied research in the development of solid-state batteries by SPS.

  13. Synthesis and regulation of α-LiZnPO4.H2O via a solid-state reaction at low-heating temperatures

    International Nuclear Information System (INIS)

    Liao Sen; Chen Zhipeng; Tian Xiaozhen; Wu Wenwei

    2009-01-01

    A simple and novel route for the synthesis of a lithium zinc phosphate hydrate, α-LiZnPO 4 .H 2 O, was studied, and the target product was obtained with LiH 2 PO 4 .H 2 O and ZnCO 3 as raw materials and polyethylene glycol-400 (PEG-400) as a surfactant via a one step solid-state reaction at room temperature (25 deg. C). The product was characterized with X-ray powder diffraction (XRD), thermogravimetric analysis and the 1st derivativative of thermogravimetric analysis (TG/DTG) and Fourier transform infrared spectroscopy (FTIR). The comparison experimental results suggested that aging temperature controlled the products of the synthesis, that is, the α-LiZnPO 4 .H 2 O was formed when the reaction mixture was aged at room temperature, and the α-LiZnPO 4 was obtained when the reaction mixture was aged at 80 deg. C.

  14. Drug-Excipient Interactions in the Solid State: The Role of Different Stress Factors.

    Science.gov (United States)

    Gressl, Corinna; Brunsteiner, Michael; Davis, Adrian; Landis, Margaret; Pencheva, Klimentina; Scrivens, Garry; Sluggett, Gregory W; Wood, Geoffrey P F; Gruber-Woelfler, Heidrun; Khinast, Johannes G; Paudel, Amrit

    2017-12-04

    Understanding properties and mechanisms that govern drug degradation in the solid state is of high importance to ensure drug stability and safety of solid dosage forms. In this study, we attempt to understand drug-excipient interactions in the solid state using both theoretical and experimental approaches. The model active pharmaceutical ingredients (APIs) under study are carvedilol (CAR) and codeine phosphate (COP), which are known to undergo esterification with citric acid (CA) in the solid state. Starting from the crystal structures of two different polymorphs of each compound, we calculated the exposure and accessibility of reactive hydroxyl groups for a number of relevant crystal surfaces, as well as descriptors that could be associated with surface stabilities using molecular simulations. Accelerated degradation experiments at elevated temperature and controlled humidity were conducted to assess the propensity of different solid forms of the model APIs to undergo chemical reactions with anhydrous CA or CA monohydrate. In addition, for CAR, we studied the solid state degradation at varying humidity levels and also under mechano-activation. Regarding the relative degradation propensities, we found that variations in the exposure and accessibility of molecules on the crystal surface play a minor role compared to the impact of molecular mobility due to different levels of moisture. We further studied drug-excipient interactions under mechano-activation (comilling of API and CA) and found that the reaction proceeded even faster than in physical powder mixtures kept at accelerated storage conditions.

  15. Modeling of positron states and annihilation in solids

    International Nuclear Information System (INIS)

    Puska, M.J.

    2003-01-01

    Theoretical models and computational aspects to describe positron states and to predict positron annihilation characteristics in solids are discussed. The comparison of the calculated positron lifetimes, core annihilation lineshapes, and two-dimensional angular correlation maps with experimental results are used in identifying the structure (including the chemical composition) of vacancy-type defects and their development e.g. during thermal annealing. The basis of the modeling is the two-component density-functional theory. The ensuing approximations and the state-of-the-art electronic-structure computation methods enable practical schemes with a quantitative predicting power. (author)

  16. Electron transfer reactions in microporous solids. Progress report, September 1990--January 1993

    Energy Technology Data Exchange (ETDEWEB)

    Mallouk, T.E.

    1993-01-01

    Basic thrust the research program involves use of microporous solids (zeolites, clays, layered and tunnel structure oxide semiconductors) as organizing media for artificial photosynthetic systems. Purpose of the microporous solid is twofold. First, it induces spatial organization of photoactive and electroactive components (sensitizers, semiconductor particles, electron relays, and catalysts) at the solid-solution interface, enhancing the quantum efficiency of charge separation and separating physically the ultimate electron donor and acceptor in the electron transport chain. Second, since the microcrystalline solid admits only molecules of a certain charge and size, it is possible to achieve permanent charge separation by sieving chemical photoproducts (e.g., H{sub 2} and I{sub 3}{sup {minus}}, or H{sub 2} and O{sub 2)} from each other. Spectroscopic and electrochemical methods are used to study the kinetics of electron transfer reactions in these hybrid molecular/solid state assemblies.

  17. The solid state track detectors for α-particles angular distribution measurements

    International Nuclear Information System (INIS)

    Bakr, M.H.S.

    1978-01-01

    The solid state track detectors technique is described in details from the point of view of applying them in nuclear reactions research. Using an optimum developing solution, the etching rate of polycarbonate detector was found to be 10.5 μ/hour. The energy resolution of this detector was estimated using 241 Am α-source at α-energies between 1 and 3 Mev. The scattering chamber designed for angular distribution measurements using solid state track detectors is described. A special schematic normograph for range-energy-degrading foils relation is given

  18. Solid-state reactions during mechanical alloying of ternary Fe-Al-X (X=Ni, Mn, Cu, Ti, Cr, B, Si) systems: A review

    Science.gov (United States)

    Hadef, Fatma

    2016-12-01

    The last decade has witnessed an intensive research in the field of nanocrystalline materials due to their enhanced properties. A lot of processing techniques were developed in order to synthesis these novel materials, among them mechanical alloying or high-energy ball milling. In fact, mechanical alloying is one of the most common operations in the processing of solids. It can be used to quickly and easily synthesize a variety of technologically useful materials which are very difficult to manufacture by other techniques. One advantage of MA over many other techniques is that is a solid state technique and consequently problems associated with melting and solidification are bypassed. Special attention is being paid to the synthesis of alloys through reactions mainly occurring in solid state in many metallic ternary Fe-Al-X systems, in order to improve mainly Fe-Al structural and mechanical properties. The results show that nanocrystallization is the common result occurring in all systems during MA process. The aim of this work is to illustrate the uniqueness of MA process to induce phase transformation in metallic Fe-Al-X (X=Ni, Mn, Cu, Ti, Cr, B, Si) systems.

  19. Detection of DNA hybridizations using solid-state nanopores

    International Nuclear Information System (INIS)

    Balagurusamy, Venkat S K; Weinger, Paul; Sean Ling, Xinsheng

    2010-01-01

    We report an experimental study of using DNA translocation through solid-state nanopores to detect the sequential arrangement of two double-stranded 12-mer hybridization segments on a single-stranded DNA molecule. The sample DNA is a trimer molecule formed by hybridizing three single-stranded oligonucleotides. A polystyrene bead is attached to the end of the trimer DNA, providing a mechanism in slowing down the translocation and suppressing the thermal diffusion, thereby allowing the detection of short features of DNA by standard patch-clamp electronics. The electrical signature of the translocation of a trimer molecule through a nanopore has been identified successfully in the temporal traces of ionic current. The results reported here represent the first successful attempt in using a solid-state nanopore as an ionic scanning device in resolving individual hybridization segments (or 'probes') on a DNA molecule.

  20. Detection of DNA hybridizations using solid-state nanopores

    Energy Technology Data Exchange (ETDEWEB)

    Balagurusamy, Venkat S K; Weinger, Paul; Sean Ling, Xinsheng, E-mail: Xinsheng_Ling@brown.edu [Department of Physics, Brown University, Providence, RI 02912 (United States)

    2010-08-20

    We report an experimental study of using DNA translocation through solid-state nanopores to detect the sequential arrangement of two double-stranded 12-mer hybridization segments on a single-stranded DNA molecule. The sample DNA is a trimer molecule formed by hybridizing three single-stranded oligonucleotides. A polystyrene bead is attached to the end of the trimer DNA, providing a mechanism in slowing down the translocation and suppressing the thermal diffusion, thereby allowing the detection of short features of DNA by standard patch-clamp electronics. The electrical signature of the translocation of a trimer molecule through a nanopore has been identified successfully in the temporal traces of ionic current. The results reported here represent the first successful attempt in using a solid-state nanopore as an ionic scanning device in resolving individual hybridization segments (or 'probes') on a DNA molecule.

  1. Enriched Boron-Doped Amorphous Selenium Based Position-Sensitive Solid-State Thermal Neutron Detector for MPACT Applications

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Krishna [Univ. of South Carolina, Columbia, SC (United States)

    2017-09-29

    High-efficiency thermal neutron detectors with compact size, low power-rating and high spatial, temporal and energy resolution are essential to execute non-proliferation and safeguard protocols. The demands of such detector are not fully covered by the current detection system such as gas proportional counters or scintillator-photomultiplier tube combinations, which are limited by their detection efficiency, stability of response, speed of operation, and physical size. Furthermore, world-wide shortage of 3He gas, required for widely used gas detection method, has further prompted to design an alternative system. Therefore, a solid-state neutron detection system without the requirement of 3He will be very desirable. To address the above technology gap, we had proposed to develop new room temperature solidstate thermal neutron detectors based on enriched boron (10B) and enriched lithium (6Li) doped amorphous Se (As- 0.52%, Cl 5 ppm) semiconductor for MPACT applications. The proposed alloy materials have been identified for its many favorable characteristics - a wide bandgap (~2.2 eV at 300 K) for room temperature operation, high glass transition temperature (tg ~ 85°C), a high thermal neutron cross-section (for boron ~ 3840 barns, for lithium ~ 940 barns, 1 barn = 10-24 cm2), low effective atomic number of Se for small gamma ray sensitivity, and high radiation tolerance due to its amorphous structure.

  2. ''Solid-state fusion'' effects

    International Nuclear Information System (INIS)

    Thompson, D.T.

    1990-01-01

    The ''Solid-State Fusion'' or ''Cold Fusion'' phenomenon, including excess heat generation and the production of nuclear particles, was first reported by Professors Martin Fleischmann and B. Stanley Pons in March 1989. The phenomenon described (the anomalous effects observed when deuterium oxide (heavy water) is electrolysed using a palladium cathode and a platinum anode in the presence of lithium deuteroxide) has many fascinating facets, not least of which is the fact that investigators are unable to produce the effects ''on demand''. Many of the experimental variables which seem to be significant were described and discussed at the ''First Annual Conference on Cold Fusion'' which was held in Salt Lake City, Utah, USA, from 29th to 31st March 1990. The information presented at the conference is summarised here. Some papers addressed the excess heat effects observed, some the nuclear particles, and others the theoretical aspects. These are reviewed. At the end of the conference Fleischmann summarised all the areas where apparent evidence for solid state fusion had been obtained during the past year, namely: excess enthalpy, bursts in enthalpy; tritium, bursts in tritium; neutrons, bursts in neutrons; X-rays, gamma rays and bursts in these. He recommended that emphasis should now be concentrated on confirming reaction products, such as He 4 . New theories were emerging, but one year was too short a time in which to evaluate them fully. (author)

  3. Characterization of the polymer Durolon as a solid state nuclear track detector

    International Nuclear Information System (INIS)

    Pugliesi, Fabio

    2008-01-01

    The polymer Durolon has been characterized as a solid state nuclear track detector. In these detectors a track, resulting from the damages in its molecular structure, induced by a heavy charged particle, is the testimony of the passage of the particle through the polymer. In order to characterize the Durolon the track diameter, track production rate, light transmission through the polymer and the critical angle of incidence of the particle have been studied. The main objective of such studies was to provide the necessary subsidies to understand the information registered. The damages have been induced by alpha particles from the nuclear reaction 10 B(n,α) 7 Li, by irradiating a boron screen in a thermal neutron field from an experimental facility installed in the beam-hole 08 of the IEA-R1 nuclear research reactor of IPEN-CNEN/SP. The study of the parameters have been performed by using a digital system developed in the present work. Its use has provided a higher quality and quickness regarding data acquisition and data analysis as well as the opportunity to quantify several other parameters regarding the imaging formation theory in solid state nuclear track detectors. The characteristics of the Durolon have been compared with the ones of two other detectors Makrofol-E and Makrofol-DE and have demonstrated its potentiality to use. (author)

  4. Solid thermoluminescent dosemeter of sodium tetraborate and brazilian fluorite sensible to thermal neutrons

    International Nuclear Information System (INIS)

    Fratin, L.; Cruz, M.T. da

    1987-01-01

    A solid termoluminescent dosemeter of sodium tetraborate and brazilian fluorite sensible to thermal neutrons is described. The nuclears reactions 1) 10 B + n → 7 Li + He + Q1 (6,1%) where: Q1=2,79 MeV and Eα1 = 1,758 MeV and 2) 10 B + n → 7 Li* + 4 He + Q2 (93,9%) where: Q2 = 2,316 MeV and E2α 2 = 1,474 MeV are responsible by the thermoluminescent response of the thermal neutrons dosemeters. The stages in the fabrication process of this dosemeter of which are:1) sodium tetraborate vitrification, 2) mixture and pressing 3) sintering are cited. The obtainment of a natural fluorite dosemeter with sodium chloride is also shown. (C.G.C.) [pt

  5. Spectroscopic and Electrochemical Properties of Lithium-Rich LiFePO4 Cathode Synthesized by Solid-State Reaction

    Science.gov (United States)

    Rosaiah, P.; Hussain, O. M.; Zhu, Jinghui; Qiu, Yejun

    2017-08-01

    Lithium iron phosphate (Li x FePO4) is synthesized by a solid-state reaction method. The structural, electrical and electrochemical properties are studied in detail. It is found that the increment of lithium concentration (up to x = 1.05) does not affect the structure of LiFePO4 but improves its electrical conductivity as well as electrochemical performance. Surface morphological studies exhibited the formation of rod-like nanoparticles with small size. Electric and dielectric properties are also investigated over a frequency range of 1 Hz-1 MHz at different temperatures. The conductivity increased with increasing temperature, which follows the Arrhenius relation with the activation energy of about 0.31 eV. And the electrochemical tests found that the Li1.05FePO4 cathode possessed improved discharge capacity with better cycling performance.

  6. Thermal effects of variable material properties and metamorphic reactions in a three-component subducting slab

    DEFF Research Database (Denmark)

    Chemia, Zurab; Dolejš, David; Steinle-Neumann, Gerd

    2015-01-01

    We explore the effects of variable material properties, phase transformations, and metamorphic devolatilization reactions on the thermal structure of a subducting slab using thermodynamic phase equilibrium calculations combined with a thermal evolution model. The subducting slab is divided...... into three layers consisting of oceanic sediments, altered oceanic crust, and partially serpentinized or anhydrous harzburgite. Solid-fluid equilibria and material properties are computed for each layer individually to illustrate distinct thermal consequences when chemical and mechanical homogenization...... indicate that subducting sediments and oceanic crust warm by 40 and 70°C, respectively, before the effect of wedge convection and heating is encountered at 1.7 GPa. Retention of fluid in the slab pore space plays a negligible role in oceanic crust and serpentinized peridotites. By contrast, the large...

  7. Solid-state laser engineering

    CERN Document Server

    Koechner, Walter

    1999-01-01

    Solid-State Laser Engineering, written from an industrial perspective, discusses in detail the characteristics, design, construction, and performance of solid-state lasers. Emphasis is placed on engineering and practical considerations; phenomenological aspects using models are preferred to abstract mathematical derivations. This new edition has extensively been updated to account for recent developments in the areas of diode-laser pumping, laser materials, and nonlinear crystals. Walter Koechner received a doctorate in Electrical Engineering from the University of Technology in Vienna, Austria, in 1965. He has published numerous papers in the fields of solid-state physics, optics, and lasers. Dr. Koechner is founder and president of Fibertek, Inc., a research firm specializing in the design, development, and production of advanced solid-state lasers, optical radars, and remote-sensing systems.

  8. Solid-state synthesis of Li_4Ti_5O_1_2 whiskers from TiO_2-B

    International Nuclear Information System (INIS)

    Yao, Wenjun; Zhuang, Wei; Ji, Xiaoyan; Chen, Jingjing; Lu, Xiaohua; Wang, Changsong

    2016-01-01

    Highlights: • The Li_4Ti_5O_1_2 whiskers were synthesized from TiO_2-B whiskers via a solid state reaction. • The TiO_2-B crystal structure for lithium diffusion is easier than anatase. • The separated diffusion and reaction process is crucial for the solid-state syntheses of Li_4Ti_5O_1_2 whiskers. - Abstract: In this work, Li_4Ti_5O_1_2 (LTO) was synthesized from the precursors of TiO_2-B and anatase whiskers, respectively. The synthesized LTO whiskers from TiO_2-B whiskers via a solid state reaction at 650 °C have a high degree of crystallinity with an average diameter of 300 nm. However, when anatase whiskers were used as the precursor, only particle morphology LTO was produced at 750 °C. The further analysis of the precursors, the intermediate products and the final products reveal that the crystal structure of the anatase hinders the diffusion of lithium, leading to a typical reaction–diffusion process. Under this condition, only particle morphology LTO can be produced. However, the crystal structure of the TiO_2-B is easy for lithium diffusion and the process is performed in two separated steps (i.e., diffusion and reaction), which makes it possible to decrease the solid-state reaction temperature down to 650 °C and then maintain the morphologies of whiskers.

  9. Materials research for passive solar systems: Solid-state phase-change materials

    Science.gov (United States)

    Benson, D. K.; Webb, J. D.; Burrows, R. W.; McFadden, J. D. O.; Christensen, C.

    1985-03-01

    A set of solid-state phase-change materials is being evaluated for possible use in passive solar thermal energy storage systems. The most promising materials are organic solid solutions of pentaerythritol (C5H12O4), pentaglycerinve (C5H12O3), and neopentyl glycol (C5H12O2). Solid solution mixtures of these compounds can be tailored so that they exhibit solid-to-solid phase transformations at any desired temperature between 25 C and 188 C, and have latent heats of transformation etween 20 and 70 cal/g. Transformation temperatures, specific heats, and latent heats of transformation have been measured for a number of these materials. Limited cyclic experiments suggest that the solid solutions are stable. These phase-change materials exhibit large amounts of undercooling; however, the addition of certain nucleating agents as particulate dispersions in the solid phase-change material greatly reduces this effect. Computer simulations suggest that the use of an optimized solid-state phase-change material in a Trombe wall could provide better performance than a concrete Trombe wall four times thicker and nine times heavier.

  10. Synthesis and characterization of BaNiO3 using a solid-state ...

    Indian Academy of Sciences (India)

    2017-07-26

    Jul 26, 2017 ... In the present study, the preparation of BaNiO3 nano-oxide is reported via simple solid-state thermal decompo- ... Oxides; perovskite; magnetic fluid; XRD; SEM; VSM. 1. .... ray spectroscopy (EDS) using gold-coated samples.

  11. Thermal ion-molecule reactions in oxygen-containing molecules

    International Nuclear Information System (INIS)

    Kumakura, Minoru

    1981-02-01

    The energetics of ions and the thermal ion-molecule reactions in oxygen-containing molecules have been studied with a modified time-of-flight mass spectrometer. It was found that the translational energy of ion can be easily obtained from analysis of the decay curve using the time-of-flight mass spectrometer. The condensation-elimination reactions proceeded via cross- and homo-elimination mechanism in which the nature of intermediate-complex could be correlated with the nature of reactant ion. It was elucidated that behavior of poly-atomic oxygen-containing ions on the condensation-elimination reactions is considerably influenced by their oxonium ion structures having functional groups. In addition, the rate constants of the condensation-elimination reactions have affected with the energy state of reactant ion and the dipole moment and/or the polarizability of neutral molecule. It was clarified that the rate constants of the ion-molecule clustering reactions in poly-atomic oxygen-containing molecules such as cyclic ether of six member rings are very large and the cluster ions are stable owing to the large number of vibrational degree of freedom in the cluster ions. (author)

  12. Application of solid state track detector to neutron dosimetry

    International Nuclear Information System (INIS)

    Tsuruta, Takao

    1979-01-01

    Though solid state track detectors (SSTD) are radiation measuring instrument for heavy charged particles by itself, it can be used as radiation measuring instrument for neutrons, if nuclear reactions such as (n, f) or (n, α) reaction are utilized. Since the means was found, which permits to observe the tracks of heavy charged particles in a solid with an optical microscope by chemically etching the tracks to enlarge them to etch pits, various types of detectors have been developed for the purpose of measuring neutron dose. The paper is described on the materials and construction of the SSTDs for neutron dosimetry, and the sensitivity is explained with mathematical equations. The features of neutron dosimetry with SSTDs are as follows: They are compact, and scarcely disturb neutron field, thus delicate dose distribution can be known; integration measurement is possible regardless of dose rate values because of integrating type detectors; it is not influenced by β-ray or γ-ray except the case when there is high energy radiation such as causing photonuclear reactions or high dose such as degrading solids, it has pretty high sensitivity; track fading is negligible during the normal measuring time around room temperature; and the etching images of tracks are relatively clear, and various automatic counting systems can be employed. (Wakatsuki, Y.)

  13. Understanding solid state physics

    CERN Document Server

    Holgate, Sharon Ann

    2009-01-01

    Where Sharon Ann Holgate has succeeded in this book is in packing it with examples of the application of solid state physics to technology. … All the basic elements of solid state physics are covered … . The range of materials is good, including as it does polymers and glasses as well as crystalline solids. In general, the style makes for easy reading. … Overall this book succeeds in showing the relevance of solid state physics to the modern world … .-Contemporary Physics, Vol. 52, No. 2, 2011I was indeed amused and inspired by the wonderful images throughout the book, carefully selected by th

  14. Growth of self-textured Ga3+-substituted Li7La3Zr2O12 ceramics by solid state reaction and their significant enhancement in ionic conductivity

    Science.gov (United States)

    Qin, Shiying; Zhu, Xiaohong; Jiang, Yue; Ling, Ming'en; Hu, Zhiwei; Zhu, Jiliang

    2018-03-01

    A highly self-textured Ga2O3-substituted Li7La3Zr2O12 (LLZO-Ga) solid electrolyte with a nominal composition of Li6.55Ga0.15La3Zr2O12 is obtained by a simple and low-cost solid-state reaction technique, requiring no seed crystals to achieve grain orientation. The as-prepared self-textured LLZO-Ga shows a strong (420) preferred orientation with a high Lotgering factor of 0.91. Coherently, a terrace-shaped microstructure consisting of many parallel layers, indicating a two-dimensional-like growth mode, is clearly observed in the self-textured sample. As a result, the highly self-textured garnet-type lithium-ion conducting solid electrolyte of LLZO-Ga exhibits an extremely high ionic conductivity, reaching a state-of-the-art level of 2.06 × 10-3 S cm-1 at room temperature (25 °C) and thus shedding light on an important strategy for improving the structure and ionic conductivity of solid electrolytes.

  15. The influence of the solid thermal conductivity on active magnetic regenerators

    DEFF Research Database (Denmark)

    Nielsen, Kaspar Kirstein; Engelbrecht, Kurt

    2012-01-01

    The influence of the thermal conductivity of the regenerator solid on the performance of a flat plate active magnetic regenerator (AMR) is investigated using an established numerical AMR model. The cooling power at different (fixed) temperature spans is used as a measure of the performance...... for a range of thermal conductivities, operating frequencies, a long and short regenerator, and finally a regenerator with a low and a high number of transfer units (NTU) regenerator. In this way the performance is mapped out and the impact of the thermal conductivity of the solid is probed. Modeling shows...... that under certain operating conditions, the AMR cycle is sensitive to the solid conductivity. It is found that as the operating frequency is increased it is not only sufficient to have a high NTU regenerator but the regenerator performance will also benefit from increased thermal conductivity in the solid...

  16. Improving Reliability of High Power Quasi-CW Laser Diode Arrays for Pumping Solid State Lasers

    Science.gov (United States)

    Amzajerdian, Farzin; Meadows, Byron L.; Baker, Nathaniel R.; Barnes, Bruce W.; Baggott, Renee S.; Lockard, George E.; Singh, Upendra N.; Kavaya, Michael J.

    2005-01-01

    Most Lidar applications rely on moderate to high power solid state lasers to generate the required transmitted pulses. However, the reliability of solid state lasers, which can operate autonomously over long periods, is constrained by their laser diode pump arrays. Thermal cycling of the active regions is considered the primary reason for rapid degradation of the quasi-CW high power laser diode arrays, and the excessive temperature rise is the leading suspect in premature failure. The thermal issues of laser diode arrays are even more drastic for 2-micron solid state lasers which require considerably longer pump pulses compared to the more commonly used pump arrays for 1-micron lasers. This paper describes several advanced packaging techniques being employed for more efficient heat removal from the active regions of the laser diode bars. Experimental results for several high power laser diode array devices will be reported and their performance when operated at long pulsewidths of about 1msec will be described.

  17. Ag_3PO_4 Microcrystals Synthesized by Room-Temperature Solid State Reaction: Enhanced Photocatalytic Activity and Photoelectronchemistry Performance

    International Nuclear Information System (INIS)

    Hao Chen-Chun; Xu Jie; Shi Hong-Long; Fu Jun-Li; Zou Bin; Meng Shan; Wang Wen-Zhong; Jia Ying

    2015-01-01

    Ag_3PO_4 microcrystals with highly enhanced visible light photocatalytic activity are prepared by a facile and simple solid state reaction at room temperature. The composition, morphology and optical properties of the as-prepared Ag_3PO_4 microcrystals are characterized by x-ray diffraction, scanning electron microscopy and UV-vis diffuse reflectance spectra. The photocatalytic properties of Ag_3PO_4 are investigated by the degradation of both methylene blue and methyl orange dyes under visible light irradiation. The as-prepared Ag_3PO_4 microcrystals possess high photocatalytic oxygen production with the rate of 673 μmolh"−"1 g"−"1. Moreover, the as-prepared Ag_3PO_4 microcrystals show an enhanced photoelectrochemistry performance under irradiation of visible light. (paper)

  18. Solid-state laser engineering

    CERN Document Server

    Koechner, Walter

    1996-01-01

    Solid-State Laser Engineering, written from an industrial perspective, discusses in detail the characteristics, design, construction, and performance of solid-state lasers. Emphasis is placed on engineering and practical considerations; phenomenological aspects using models are preferred to abstract mathematical derivations. This new edition has extensively been updated to account for recent developments in the areas of diode-laser pumping, mode locking, ultrashort-pulse generation etc. Walter Koechner received a doctorate in Electrical Engineering from the University of Technology in Vienna, Austria, in 1965. He has published numerous papers in the fields of solid-state physics, optics, and lasers. Dr. Koechner is founder and president of Fibertek, Inc., a research firm specializing in the design, development, and production of advanced solid-state lasers, optical radars, and remote-sensing systems.

  19. Quantifying atom addition reactions on amorphous solid water: a review of recent laboratory advances

    Science.gov (United States)

    He, Jiao; Vidali, Gianfranco

    2018-06-01

    Complex organic molecules found in space are mostly formed on and in the ice mantle covering interstellar dust grains. In clouds where ionizing irradiation is insignificant, chemical reactions on the ice mantle are dominated by thermal processes. Modeling of grain surface chemistry requires detailed information from the laboratory, including sticking coefficients, binding energies, diffusion energy barriers, mechanism of reaction, and chemical desorption rates. In this talk, recent laboratory advances in obtaining these information would be reviewed. Specifically, this talk will focus on the efforts in our group in: 1) Determining the mechanism of atomic hydrogen addition reactions on amorphous solid water (ASW); 2) Measuring the chemical desorption coefficient of H+O3-->O2+OH using the time-resolved scattering technique; and 3) Measuring the diffusion energy barrier of volatile molecules on ASW. Further laboratory studies will be suggested.This research was supported by NSF Astronomy & Astrophysics Research Grant #1615897.

  20. Technical aspects in the obtention of tissue autoradiography using solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Saint Martin, Gisela; Bernaola, Omar A.; Pozzi, Emiliano; Thorp, Silvia; Cabrini, Romulo L.; Tomasi, V.H.

    2007-01-01

    The autoradiography images produced in solid state nuclear track detectors by heavy ions originated in tissue provide relevant information about the spatial biodistribution of heavy particle emitters. Some preliminary aspects of the autoradiography technique are evaluated by two experiments which are in progress, using Lexan and CR 39 foils as solid state nuclear track detectors. In the first case, a tissue sample from rat kidney intoxicated with UO 2 (NO 3 ) 2 was embedded in paraffin and put in contact with a 1 mm thick CR 39 foil. After a two months exposure the foil was chemically developed resulting in scarce tracks. A satisfactory image cannot be obtained in these conditions. More prolonged exposure time is needed to obtain better images of such samples. The second experience consisted in the irradiation of fresh kidney tissue slices from healthy rats in contact with 250 μm thick Lexan foils, in a thermal neutrons flux. The irradiation was performed at the RA-3 facility of the Ezeiza Atomic Center (CAE). The contribution to image produced by tracks of particles due to reactions between neutrons and tissue elements (i.e. 14 N) was evaluated. The etching conditions should be modified in order to desensitize the detector material. (author) [es

  1. CW-Laser-Induced Solid-State Reactions in Mixed Micron-Sized Particles of Silicon Monoxide and Titanium Monoxide: Nano-Structured Composite with Visible Light Absorption

    Czech Academy of Sciences Publication Activity Database

    Křenek, T.; Tesař, J.; Kupčík, Jaroslav; Netrvalová, M.; Pola, M.; Jandová, Věra; Pokorná, Dana; Cuřínová, Petra; Bezdička, Petr; Pola, Josef

    2017-01-01

    Roč. 27, č. 6 (2017), s. 1640-1648 ISSN 1574-1443 Institutional support: RVO:61388980 ; RVO:67985858 Keywords : Cw CO2 laser heating * IR laser imaging * Silicon monoxide * Solid state redox reactions * Ti/Si/O composite * Titanium monoxide Subject RIV: CA - Inorganic Chemistry; CI - Industrial Chemistry, Chemical Engineering (UCHP-M) OBOR OECD: Inorganic and nuclear chemistry; Chemical process engineering (UCHP-M) Impact factor: 1.577, year: 2016

  2. Solid state chemistry an introduction

    CERN Document Server

    Smart, Lesley E

    2012-01-01

    ""Smart and Moore are engaging writers, providing clear explanations for concepts in solid-state chemistry from the atomic/molecular perspective. The fourth edition is a welcome addition to my bookshelves. … What I like most about Solid State Chemistry is that it gives simple clear descriptions for a large number of interesting materials and correspondingly clear explanations of their applications. Solid State Chemistry could be used for a solid state textbook at the third or fourth year undergraduate level, especially for chemistry programs. It is also a useful resource for beginning graduate

  3. The solid state maser

    CERN Document Server

    Orton, J W; Walling, J C; Ter Haar, D

    1970-01-01

    The Solid State Maser presents readings related to solid state maser amplifier from the first tentative theoretical proposals that appeared in the early 1950s to the successful realization of practical devices and their application to satellite communications and radio astronomy almost exactly 10 years later. The book discusses a historical account of the early developments (including that of the ammonia maser) of solid state maser; the properties of paramagnetic ions in crystals; the development of practical low noise amplifiers; and the characteristics of maser devices designed for communica

  4. Computational modeling of chemical reactions and interstitial growth and remodeling involving charged solutes and solid-bound molecules.

    Science.gov (United States)

    Ateshian, Gerard A; Nims, Robert J; Maas, Steve; Weiss, Jeffrey A

    2014-10-01

    Mechanobiological processes are rooted in mechanics and chemistry, and such processes may be modeled in a framework that couples their governing equations starting from fundamental principles. In many biological applications, the reactants and products of chemical reactions may be electrically charged, and these charge effects may produce driving forces and constraints that significantly influence outcomes. In this study, a novel formulation and computational implementation are presented for modeling chemical reactions in biological tissues that involve charged solutes and solid-bound molecules within a deformable porous hydrated solid matrix, coupling mechanics with chemistry while accounting for electric charges. The deposition or removal of solid-bound molecules contributes to the growth and remodeling of the solid matrix; in particular, volumetric growth may be driven by Donnan osmotic swelling, resulting from charged molecular species fixed to the solid matrix. This formulation incorporates the state of strain as a state variable in the production rate of chemical reactions, explicitly tying chemistry with mechanics for the purpose of modeling mechanobiology. To achieve these objectives, this treatment identifies the specific theoretical and computational challenges faced in modeling complex systems of interacting neutral and charged constituents while accommodating any number of simultaneous reactions where reactants and products may be modeled explicitly or implicitly. Several finite element verification problems are shown to agree with closed-form analytical solutions. An illustrative tissue engineering analysis demonstrates tissue growth and swelling resulting from the deposition of chondroitin sulfate, a charged solid-bound molecular species. This implementation is released in the open-source program FEBio ( www.febio.org ). The availability of this framework may be particularly beneficial to optimizing tissue engineering culture systems by examining the

  5. Investigations of structure, bonding, and reactions of radiation-induced free radicals in the solid state using electron spin resonance spectroscopy

    International Nuclear Information System (INIS)

    Hudson, R.L.

    1978-01-01

    Electron spin resonance spectroscopy (ESR) has been used to study the structure, bonding, and reactions of several types of free radicals produced by γ irradiation of solids at 77K. Well-defined spectral patterns and the use of photolysis and annealing treatments assisted the analyses and interpretations. The radical anion BF 3 - was generated and identified unequivocally in a matrix of tetramethylsilane at 77K. Both the ESR data and theoretical calculations support a pyramidal structure with a bond angle of about 110 0 . The present experiments showed that BF 3 - has ESR parameters consistent with those of the isoelectronic radicals CF 3 , NF 3 + , and F 2 NO. γ irradiation of polycrystalline trimethyl borate at 77K gave an ESR spectrum which was assigned to the dimer radical anion [(MeO) 3 B.B(OMe) 3 ] - . Radical anions of dialkyl carbonates were observed for the first time and found to undergo a β-scission reaction to produce alkyl radicals. This free radical reaction is unusual in that it proceeds both thermally and photochemically. For the dimethyl carbonate radical anion, 13 C parameters were obtained from a 13 C enriched sample. The photolysis of trapped radicals in γ irradiated carboxylic esters, RC(O)OR', was studied by ESR spectroscopy and two different reactions were characterized. Two hypervalent silicon radical anions were prepared and examined in SI(OCH 3 ) 4 . The results of the present work thus represent the first complete sets of data on the silicon 3s and 3p spin densities for such species. The first PL 3 - radical anion was prepared by the γ irradiation of crystalline trimethylphosphite, and identified through its photolysis reactions and from the results of radiation chemical experiments

  6. Investigations in the field of solid-state polymerization Pt. 37

    International Nuclear Information System (INIS)

    Mahr, L.; Cser, F.; Kovacs, G.; Hardy, Gy.

    1978-01-01

    Chloranil (CA) and bromanil (BA) which have otherwise similar radiation-chemical properties affect the solid state polymerization of acenaphthylene (ACN) in different manner. CA decreases the rate of polymerization proportionally to its concentration and besides, it also decreases the conversion limit and the molecular weight of the product. BA does not influence the reaction up to a conversion of 20%, but soon afterwards the conversion limit of the polymerization is reached. This limit, above 8M% BA content, is independent of the BA concentration. The reason for the different behaviour is that while BA forms an ideal eutectics with ACN, CA forms a solid solution of limited miscibility at the temperature of the experiments. Both pairs of compounds give charge transfer complex in solid state. The charge transfer complex of BA exists merely at the boundary layer of the crystals, but that of CA is within the crystal lattice of ACN as in a solid solvent. In none of the studied cases could be detected the charge transfer complex with its own specific crystal structure. The effect of CA on the solid state polymerization of ACN is discussed on the basis of the results obtained by PPP and CNDO/2 calculations on ACN and CA. (author)

  7. Facile synthesis of PbTiO3 truncated octahedra via solid-state reaction and their application in low-temperature CO oxidation by loading Pt nanoparticles

    KAUST Repository

    Yin, Simin; Zhu, Yihan; Ren, Zhaohui; Chao, Chunying; Li, Xiang; Wei, Xiao; Shen, Ge; Han, Yu; Han, Gaorong

    2014-01-01

    Perovskite PbTiO3 (PTO) nanocrystals with a truncated octahedral morphology have been prepared by a facile solid-state reaction. Pt nanoparticles preferentially nucleated on the {111} facet of PTO nanocrystals exhibit a remarkable low-temperature catalytic activity towards CO oxidation from a temperature as low as 30 °C and achieve 100% conversion at ∼50 °C. © 2014 the Partner Organisations.

  8. Thermophilic cellulase production by Taralomyces sp. in solid-state cultivation

    Energy Technology Data Exchange (ETDEWEB)

    Nishio, N; Kurisu, H; Nagai, S

    1981-01-01

    The effects of substrate moisture content and culture temperature on the production of carboxymethyl cellulase (CMCase) and avicel hydrolyzing activity (avicelase) by Taralomyces sp. were studied in solid state cultivation using wheat bran. The moisture content of wheat bran was maintained at 40, 45, 50, 55 and 58/sup 0/C throughout the solid state cultures. The maximum avicelase formation was observed when the substrate moisture content and the culture temperature were maintained at 60% and 45/sup 0/C, respectively. The maximum CMCase formation was observed when the moisture content was maintained between 60 and 70% at 50/sup 0/C. Optimum reaction temperatures of CMCase and avicelase were 80 and 60/sup 0/C, respectively.

  9. Solid state chemistry and its applications

    CERN Document Server

    West, Anthony R

    2013-01-01

    Solid State Chemistry and its Applications, 2nd Edition: Student Edition is an extensive update and sequel to the bestselling textbook Basic Solid State Chemistry, the classic text for undergraduate teaching in solid state chemistry worldwide. Solid state chemistry lies at the heart of many significant scientific advances from recent decades, including the discovery of high-temperature superconductors, new forms of carbon and countless other developments in the synthesis, characterisation and applications of inorganic materials. Looking forward, solid state chemistry will be crucial for the

  10. Strain-induced structural changes and chemical reactions. 1: Thermomechanical and kinetic models

    International Nuclear Information System (INIS)

    Levitas, V.I.; Nesterenko, V.F.; Meyers, M.A.

    1998-01-01

    Strain-induced chemical reactions were observed recently (Nesterenko et al) in experiments in the shear band in both Ti-Si and Nb-Si mixtures. Reactions can start in the solid state or after melting of at least one component. One of the aims is to find theoretically whether there are possible macroscopic mechanisms of mechanical intensification of the above and other chemical reactions due to plastic shear in the solid state. Continuum thermodynamical theory of structural changes with an athermal kinetics, which includes martensitic phase transformations, plastic strain-induced chemical reactions and polymorphic transformations, is developed at finite strains. The theory includes kinematics, criterion of structural change and extremum principle for determination of all unknown variable parameters for the case with neglected elastic strains. Thermodynamically consistent kinetic theory of thermally activated structural changes is suggested. The concept of the effective temperature is introduced which takes into account that temperature can vary significantly (on 1,000 K) during the chemical reactions under consideration. The theory will be applied in Part 2 of the paper for the description of chemical reactions in the shear band

  11. Microstructure, ferromagnetic and photoluminescence properties of ITO and Cr doped ITO nanoparticles using solid state reaction

    Science.gov (United States)

    Babu, S. Harinath; Kaleemulla, S.; Rao, N. Madhusudhana; Rao, G. Venugopal; Krishnamoorthi, C.

    2016-11-01

    Indium-tin-oxide (ITO) (In0.95Sn0.05)2O3 and Cr doped indium-tin-oxide (In0.90Sn0.05Cr0.05)2O3 nanoparticles were prepared using simple low cost solid state reaction method and characterized by different techniques to study their structural, optical and magnetic properties. Microstructures, surface morphology, crystallite size of the nanoparticles were studied using X-ray diffractometer (XRD), field emission scanning electron microscope (FE-SEM). From these methods it was found that the particles were about 45 nm. Chemical composition and valence states of the nanoparticles were studied using energy dispersive analysis of X-rays (EDAX) and X-ray photoelectron spectroscopy (XPS). From these techniques it was observed that the elements of indium, tin, chromium and oxygen were present in the system in appropriate ratios and they were in +3, +4, +3 and -2 oxidation states. Raman studies confirmed that the nanoparticle were free from unintentional impurities. Two broad emission peaks were observed at 330 nm and 460 nm when excited wavelength of 300 nm. Magnetic studies were carried out at 300 K and 100 K using vibrating sample magnetometer (VSM) and found that the ITO nanoparticles were ferromagnetic at 100 K and 300 K. Where-as the room temperature ferromagnetism completely disappeared in Cr doped ITO nanoparticles at 100 K and 300 K.

  12. Thermal stress analysis of sulfur deactivated solid oxide fuel cells

    Science.gov (United States)

    Zeng, Shumao; Parbey, Joseph; Yu, Guangsen; Xu, Min; Li, Tingshuai; Andersson, Martin

    2018-03-01

    Hydrogen sulfide in fuels can deactivate catalyst for solid oxide fuel cells, which has become one of the most critical challenges to stability. The reactions between sulfur and catalyst will cause phase changes, leading to increase in cell polarization and mechanical mismatch. A three-dimensional computational fluid dynamics (CFD) approach based on the finite element method (FEM) is thus used to investigate the polarization, temperature and thermal stress in a sulfur deactivated SOFC by coupling equations for gas-phase species, heat, momentum, ion and electron transport. The results indicate that sulfur in fuels can strongly affect the cell polarization and thermal stresses, which shows a sharp decrease in the vicinity of electrolyte when 10% nickel in the functional layer is poisoned, but they remain almost unchanged even when the poisoned Ni content was increased to 90%. This investigation is helpful to deeply understand the sulfur poisoning effects and also benefit the material design and optimization of electrode structure to enhance cell performance and lifetimes in various hydrocarbon fuels containing impurities.

  13. Solid State Energy Conversion Alliance (SECA) Solid Oxide Fuel Cell Program

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Minh

    2006-07-31

    This report summarizes the work performed for Phase I (October 2001 - August 2006) under Cooperative Agreement DE-FC26-01NT41245 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled 'Solid State Energy Conversion Alliance (SECA) Solid Oxide Fuel Cell Program'. The program focuses on the development of a low-cost, high-performance 3-to-10-kW solid oxide fuel cell (SOFC) system suitable for a broad spectrum of power-generation applications. During Phase I of the program significant progress has been made in the area of SOFC technology. A high-efficiency low-cost system was designed and supporting technology developed such as fuel processing, controls, thermal management, and power electronics. Phase I culminated in the successful demonstration of a prototype system that achieved a peak efficiency of 41%, a high-volume cost of $724/kW, a peak power of 5.4 kW, and a degradation rate of 1.8% per 500 hours. . An improved prototype system was designed, assembled, and delivered to DOE/NETL at the end of the program. This prototype achieved an extraordinary peak efficiency of 49.6%.

  14. Solid-state reactions during mechanical alloying of ternary Fe–Al–X (X=Ni, Mn, Cu, Ti, Cr, B, Si) systems: A review

    Energy Technology Data Exchange (ETDEWEB)

    Hadef, Fatma, E-mail: hadef77@yahoo.fr [Laboratoire de Recherche sur la Physico-Chimie des Surfaces et Interfaces, LRPCSI, Université 20 Août 1955, BP 26, Route d’El-Haddaiek, Skikda 21000 (Algeria); Département de Physique, Faculté des Sciences, Université 20 Août 1955, BP 26, Route d’El-Haddaiek, Skikda 21000 (Algeria)

    2016-12-01

    The last decade has witnessed an intensive research in the field of nanocrystalline materials due to their enhanced properties. A lot of processing techniques were developed in order to synthesis these novel materials, among them mechanical alloying or high-energy ball milling. In fact, mechanical alloying is one of the most common operations in the processing of solids. It can be used to quickly and easily synthesize a variety of technologically useful materials which are very difficult to manufacture by other techniques. One advantage of MA over many other techniques is that is a solid state technique and consequently problems associated with melting and solidification are bypassed. Special attention is being paid to the synthesis of alloys through reactions mainly occurring in solid state in many metallic ternary Fe–Al–X systems, in order to improve mainly Fe–Al structural and mechanical properties. The results show that nanocrystallization is the common result occurring in all systems during MA process. The aim of this work is to illustrate the uniqueness of MA process to induce phase transformation in metallic Fe–Al–X (X=Ni, Mn, Cu, Ti, Cr, B, Si) systems. - Highlights: • A review of state of the art on binary Fe–Al alloys was presented. • Structural and microstructural properties of MA ternary Fe–Al–X alloys were summerized. • MA process is a powerful tool for producing metallic alloys at the nanometer scale.

  15. Synthesis and mechanism of formation of oxadeazaflavines by microwave thermal cyclization of ortho-halobenzylidene barbiturates

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa-Villar, J. Daniel; Oliveira, Sandra C.G. de, E-mail: figueroa@ime.eb.br [Grupo de Quimica Medicinal, Departamento de Quimica, Instituto Militar de Engenharia, Rio de Janeiro, RJ (Brazil)

    2011-09-15

    The thermal cyclization reaction of o-halobenzylidene barbiturates was developed as an efficient and simple method for the preparation of oxadeazaflavines. The use of solid state reaction conditions with microwave irradiation afforded the products in 5 min with 47 to 98% yield. Experimental synthetic results and thermogravimetric reaction analyses agree with the molecular modeling mechanism simulation, indicating that this reaction occurs through an intramolecular hetero-Diels-Alder cyclization followed by fast re-aromatization. (author)

  16. Thermal and spectroscopic studies on solid ibuprofen complexes of lighter trivalent lanthanides

    Energy Technology Data Exchange (ETDEWEB)

    Gálico, D.A.; Holanda, B.B.C.; Guerra, R.B.; Legendre, A.O.; Rinaldo, D. [UNESP – Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260 (Brazil); Treu-Filho, O. [UNESP – Univ Estadual Paulista, Instituto de Química, São Paulo CEP 14800-900 (Brazil); Bannach, G., E-mail: gilbert@fc.unesp.br [UNESP – Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260 (Brazil)

    2014-01-10

    Highlights: • Lighter trivalent lanthanide complexes of ibuprofen have been synthesized. • The TG-FTIR allowed the identification of propane as the gas evolved during the thermal decomposition of the neodymium compound. • The thermal analysis provided information about the composition, dehydration, thermal behavior and thermal decomposition of the samples. • The theoretical and experimental spectroscopic studies suggest that the carboxylate group of ibuprofen is coordinated to the metals by a bidentate bond. - Abstract: Solid-state compounds of general formula Ln(L){sub 3}, in which L is ibuprofen and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), X-ray powder diffractometry (DRX), complexometry, Fourier-transformed infrared spectroscopy (FTIR) and thermogravimetry coupled to Fourier-transformed infrared spectroscopy (TG-FTIR) were used to characterize these compounds. The results provided information concerning the chemical composition, dehydration, coordination modes of the ligands, crystallinity of the samples, thermal behavior and thermal decomposition of the compounds. The theoretical and experimental spectroscopic studies suggest that ibuprofen coordinates through the carboxylate group as a chelating ligand.

  17. Thermal and spectroscopic studies on solid ibuprofen complexes of lighter trivalent lanthanides

    International Nuclear Information System (INIS)

    Gálico, D.A.; Holanda, B.B.C.; Guerra, R.B.; Legendre, A.O.; Rinaldo, D.; Treu-Filho, O.; Bannach, G.

    2014-01-01

    Highlights: • Lighter trivalent lanthanide complexes of ibuprofen have been synthesized. • The TG-FTIR allowed the identification of propane as the gas evolved during the thermal decomposition of the neodymium compound. • The thermal analysis provided information about the composition, dehydration, thermal behavior and thermal decomposition of the samples. • The theoretical and experimental spectroscopic studies suggest that the carboxylate group of ibuprofen is coordinated to the metals by a bidentate bond. - Abstract: Solid-state compounds of general formula Ln(L) 3 , in which L is ibuprofen and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), X-ray powder diffractometry (DRX), complexometry, Fourier-transformed infrared spectroscopy (FTIR) and thermogravimetry coupled to Fourier-transformed infrared spectroscopy (TG-FTIR) were used to characterize these compounds. The results provided information concerning the chemical composition, dehydration, coordination modes of the ligands, crystallinity of the samples, thermal behavior and thermal decomposition of the compounds. The theoretical and experimental spectroscopic studies suggest that ibuprofen coordinates through the carboxylate group as a chelating ligand

  18. Standardized Testing Program for Solid-State Hydrogen Storage Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Michael A. [Southwest Research Institute; Page, Richard A. [Southwest Research Institute

    2012-07-30

    In the US and abroad, major research and development initiatives toward establishing a hydrogen-based transportation infrastructure have been undertaken, encompassing key technological challenges in hydrogen production and delivery, fuel cells, and hydrogen storage. However, the principal obstacle to the implementation of a safe, low-pressure hydrogen fueling system for fuel-cell powered vehicles remains storage under conditions of near-ambient temperature and moderate pressure. The choices for viable hydrogen storage systems at the present time are limited to compressed gas storage tanks, cryogenic liquid hydrogen storage tanks, chemical hydrogen storage, and hydrogen absorbed or adsorbed in a solid-state material (a.k.a. solid-state storage). Solid-state hydrogen storage may offer overriding benefits in terms of storage capacity, kinetics and, most importantly, safety.The fervor among the research community to develop novel storage materials had, in many instances, the unfortunate consequence of making erroneous, if not wild, claims on the reported storage capacities achievable in such materials, to the extent that the potential viability of emerging materials was difficult to assess. This problem led to a widespread need to establish a capability to accurately and independently assess the storage behavior of a wide array of different classes of solid-state storage materials, employing qualified methods, thus allowing development efforts to focus on those materials that showed the most promise. However, standard guidelines, dedicated facilities, or certification programs specifically aimed at testing and assessing the performance, safety, and life cycle of these emergent materials had not been established. To address the stated need, the Testing Laboratory for Solid-State Hydrogen Storage Technologies was commissioned as a national-level focal point for evaluating new materials emerging from the designated Materials Centers of Excellence (MCoE) according to

  19. Studies on the luminescence properties of CaZrO3:Eu3+ phosphors prepared by the solid state reaction method

    Directory of Open Access Journals (Sweden)

    Ishwar Prasad Sahu

    2017-03-01

    Full Text Available CaZrO3:xEu3+ (x = 1.0, 2.0, 3.0, 4.0, and 5.0 mol% phosphors were successfully prepared by a solid state reaction method. The crystal structure of sintered phosphors was hexagonal phase with space group of Pm-3m. The near ultra-violet (NUV excitation, emission spectra of the CaZrO3:xEu3+ phosphors were composed of sharp line emission associated with the transitions from the excited states 5D0 to the ground state 7Fj (j = 0, 1, 2, 3, 4 of Eu3+. The results indicated that CaZrO3:xEu3+ might become an important orange-red phosphor candidate for use in white light emitting diodes (WLEDs with near-UV LED chips. The mechanoluminescence (ML intensity increases linearly with increasing impact velocity of the moving piston, suggesting that the sintered phosphors can also be useful as a stress sensor.

  20. Solid-state actinide acid phosphites from phosphorous acid melts

    International Nuclear Information System (INIS)

    Oh, George N.; Burns, Peter C.

    2014-01-01

    The reaction of UO 3 and H 3 PO 3 at 100 °C and subsequent reaction with dimethylformamide (DMF) produces crystals of the compound (NH 2 (CH 3 ) 2 )[UO 2 (HPO 2 OH)(HPO 3 )]. This compound crystallizes in space group P2 1 /n and consists of layers of uranyl pentagonal bipyramids that share equatorial vertices with phosphite units, separated by dimethylammonium. In contrast, the reaction of phosphorous acid and actinide oxides at 210 °C produces a viscous syrup. Subsequent dilution in solvents and use of standard solution-state methods results in the crystallization of two polymorphs of the actinide acid phosphites An(HPO 2 OH) 4 (An=U, Th) and of the mixed acid phosphite–phosphite U(HPO 3 )(HPO 2 OH) 2 (H 2 O)·2(H 2 O). α- and β-An(HPO 2 OH) 4 crystallize in space groups C2/c and P2 1 /n, respectively, and comprise a three-dimensional network of An 4+ cations in square antiprismatic coordination corner-sharing with protonated phosphite units, whereas U(HPO 3 )(HPO 2 OH) 2 (H 2 O) 2 ·(H 2 O) crystallizes in a layered structure in space group Pbca that is composed of An 4+ cations in square antiprismatic coordination corner-sharing with protonated phosphites and water ligands. We discuss our findings in using solid inorganic reagents to produce a solution-workable precursor from which solid-state compounds can be crystallized. - Graphical abstract: Reaction of UO 3 and H 3 PO 3 at 100 °C and subsequent reaction with DMF produces crystals of (NH 2 (CH 3 ) 2 )[UO 2 (HPO 2 OH)(HPO 3 )] with a layered structure. Reaction of phosphorous acid and actinide oxides at 210 °C produces a viscous syrup and further solution-state reactions result in the crystallization of the actinide acid phosphites An(HPO 2 OH) 4 (An=U, Th), with a three-dimensional network structure, and the mixed acid phosphite–phosphite U(HPO 3 )(HPO 2 OH) 2 (H 2 O) 2 ·(H 2 O) with a layered structure. - Highlights: • U(VI), U(IV) and Th(IV) phosphites were synthesized by solution-state

  1. Thermal conductivity of fusion solid breeder materials

    International Nuclear Information System (INIS)

    Liu, Y.Y.; Tam, S.W.

    1986-06-01

    Several simple and useful formulae for estimating the thermal conductivity of lithium-containing ceramic tritium breeder materials for fusion reactor blankets are given. These formulae account for the effects of irradiation, as well as solid breeder configuration, i.e., monolith or a packed bed. In the latter case, a coated-sphere concept is found more attractive in incorporating beryllia (a neutron multiplier) into the blanket than a random mixture of solid breeder and beryllia spheres

  2. A Model of Solid State Gas Sensors

    Science.gov (United States)

    Woestman, J. T.; Brailsford, A. D.; Shane, M.; Logothetis, E. M.

    1997-03-01

    Solid state gas sensors are widely used to measure the concentrations of gases such as CO, CH_4, C_3H_6, H_2, C_3H8 and O2 The applications of these sensors range from air-to-fuel ratio control in combustion processes including those in automotive engines and industrial furnaces to leakage detection of inflammable and toxic gases in domestic and industrial environments. As the need increases to accurately measure smaller and smaller concentrations, problems such as poor selectivity, stability and response time limit the use of these sensors. In an effort to overcome some of these limitations, a theoretical model of the transient behavior of solid state gas sensors has been developed. In this presentation, a model for the transient response of an electrochemical gas sensor to gas mixtures containing O2 and one reducing species, such as CO, is discussed. This model accounts for the transport of the reactive species to the sampling electrode, the catalyzed oxidation/reduction reaction of these species and the generation of the resulting electrical signal. The model will be shown to reproduce the results of published steady state models and to agree with experimental steady state and transient data.

  3. All-solid-state thin film battery based on well-aligned slanted LiCoO{sub 2} nanowires fabricated by glancing angle deposition

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Miyoung [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Lee, Seunghwan [High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Daehee [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Joosun, E-mail: joosun@kist.re.kr [High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Moon, Jooho, E-mail: jmoon@yonsei.ac.kr [Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2017-08-01

    Graphical abstract: We successfully fabricated well-aligned slanted LiCoO{sub 2} nanowires as a one-dimensional nanostructured cathode by glancing angle deposition to enhance the electrochemical performance of all-solid-state thin film batteries. - Highlights: • Well-aligned slanted LiCoO{sub 2} nanowires are fabricated by glancing angle deposition. • One-dimensional nanostructured LiCoO{sub 2} cathode enlarges the contact area. • All-solid-state thin film battery exhibits enhances rate capability and cycling stability. - Abstract: We fabricated all-solid-state thin film batteries based on well-aligned slanted LiCoO{sub 2} nanowires by glancing angle deposition, as a facile template-free method in order to increase the electrochemically active site, i.e., the contact area between the solid electrolyte and the electrode. A highly porous thin film composed of well-separated slanted LiCoO{sub 2} nanowires not only facilitates the penetration of solid electrolyte phase into the cathode, but also alleviates the thermally and mechanically induced stresses during post-annealing and electrochemical cycling. The all-solid-state thin film battery based on the well-aligned slanted LiCoO{sub 2} nanowires, whose contact area between electrolyte and electrode was three times as high as that of a dense thin film, could provide additional migration pathways for lithium ion diffusion due to the enlarged reaction sites. This resulted in enhanced electrochemical kinetics, thereby leading to better rate capability and long-term cyclic stability as compared to the dense LiCoO{sub 2} thin film.

  4. High Reversibility of Soft Electrode Materials in All-solid-state Batteries

    Directory of Open Access Journals (Sweden)

    Atsushi eSakuda

    2016-05-01

    Full Text Available All-solid-state batteries using inorganic solid electrolytes (SEs are considered to be ideal batteries for electric vehicles (EVs and plug-in hybrid electric vehicles (PHEVs because they are potentially safer than conventional lithium-ion batteries (LIBs. In addition, all-solid-state batteries are expected to have long battery lives owing to the inhibition of chemical side reactions because only lithium ions move through the typically used inorganic SEs. The development of high-energy (more than 300 Wh kg-1 secondary batteries has been eagerly anticipated for years. The application of high-capacity electrode active materials is essential for fabricating such batteries. Recently, we proposed metal polysulfides as new electrode materials. These materials show higher conductivity and density than sulfur, which is advantageous for fabricating batteries with relatively higher energy density. Lithium niobium sulfides, such as Li3NbS4, have relatively high density, conductivity, and rate capability among metal polysulfide materials, and batteries with these materials have capacities high enough to potentially exceed the gravimetric energy density of conventional LIBs.Favorable solid-solid contact between the electrode and electrolyte particles is a key factor for fabricating high performance all-solid-state batteries. Conventional oxide-based positive electrode materials tend to be given rise to cracks during fabrication and/or charge-discharge processes. Here we report all-solid-state cells using lithium niobium sulfide as a positive electrode material, where favorable solid-solid contact was established by using lithium sulfide electrode materials because of their high processability. Cracks were barely observed in the electrode particles in the all-solid-state cells before or after charging and discharging with a high capacity of approx. 400 mAh g-1, suggesting that the lithium niobium sulfide electrode charged and discharged without experiencing

  5. The influence of the disordered dipole subsystem on the thermal conductivity of the CO solid at low temperatures

    International Nuclear Information System (INIS)

    Sumarokov, V.; Jezowski, A.; Stachowiak, P.

    2009-01-01

    The thermal conductivity of solid CO is investigated in the temperature range 1-20 K. The experimental temperature dependence of thermal conductivity of solid CO is described using the time-relaxation method within the Debye model. The comparison of the experimental temperature dependences of the thermal conductivity of N 2 and CO shows that in the case of CO there is an additional large phonon scattering at temperatures near the maximum. Analysis of the experimental data indicates that this scattering is caused by the frozen disordered dipole subsystem, similar to a dipole glass. The scattering is described by resonant phonon scattering on tunneling states and on low-energy quasi-harmonic oscillations within the soft potential model

  6. Thermal decomposition of solid mixtures of 2-oxy-4,6-dinitramine-s-triazine (DNAM) and phase stabilized ammonium nitrate (PSAN)

    OpenAIRE

    Simões, P. N.; Pedroso, L. M.; Portugal, A. A.; Campos, J. L.

    2000-01-01

    The thermal decomposition of solid mixtures of 2-oxy-4,6-dinitramine-s-triazine (DNAM) and phase stabilized ammonium nitrate (PSAN) at different mass ratios has been studied. Simultaneous thermal analysis (DSC/TG) and thermomicroscopy have been used. It was found that PSAN promotes the lowering of the decomposition temperature of DNAM. The beginning of this process occurs when both components are in the solid state irrespective of the composition. However, the composition appears as the main ...

  7. Color Rendering Index Thermal Stability Improvement of Glass-Based Phosphor-Converted White Light-Emitting Diodes for Solid-State Lighting

    Directory of Open Access Journals (Sweden)

    Chun-Chin Tsai

    2014-01-01

    Full Text Available High color rendering index performance has been required for phosphor-converted warm-white light-emitting diodes (PC-WWLEDs in lighting industry. The characteristics of low-temperature fabricated phosphor (yellow: Ce3+:YAG, green: Tb3+:YAG, and red: CaAlClSiN3:Eu2+ doped glass were presented for applications to high color rendering index warm-white-light-emitting diodes. Color coordinates (x, y = (0.36, 0.29, quantum yield (QY = 55.6%, color rending index (CRI = 85.3, and correlated color temperature (CCT = 3923 K were characterized. Glass-based PC-WWLEDs was found able to maintain good thermal stability for long-time high-temperature operation. QY decay, CRI remenance, and chromaticity shift were also analyzed for glass- and silicone-based high-power PC-WLEDs by thermal aging at 150°C and 250°C for industrial test standard’s aging time 1008 hours. Better than the silicone’s, thermal stability of glass-based PC-WLEDs has been improved. The resulted high color rendering index (CRI glass phosphor potentially can be used as a phosphor layer for high-performance and low-cost PC-WLEDs used in next-generation indoor solid-state lighting applications.

  8. TSAAS: finite-element thermal and stress analysis of plane and axisymmetric solids with orthotropic temperature-dependent material properties

    Energy Technology Data Exchange (ETDEWEB)

    Browning, R.V.; Anderson, C.A.

    1982-02-01

    The finite element method is used to determine the temperatures, displacements, stresses, and strains in axisymmetric solids with orthotropic, temperature-dependent material properties under axisymmetric thermal and mechanical loads. The mechanical loads can be surface pressures, surface shears, and nodal point forces as well as an axial or centripetal acceleration. The continuous solid is replaced by a system of ring elements with triangular or quadrilateral cross sections. Accordingly, the method is valid for solids that are composed of many different materials and that have complex geometry. Nonlinear mechanical behavior as typified by plastic, locking, or creeping materials can be approximated. Two dimensional mesh generation, plotting, and editing features allow the computer program to be readily used. In addition to a stress analysis program that is based on a modified version of the SAAS code, TSAAS can carry out a transient thermal analysis with the finite element mesh used in stress analysis. An implicit time differencing scheme allows the use of arbitrary time steps with consequent fast running times. At specified times, the program will return to SAAS for thermal stress analysis. Nonlinear thermal properties and Arrhenius reaction kinetics are also incorporated into TSAAS. Several versions of TSAAS are in use at Los Alamos, running on CDC-7600, CRAY-1 and VAX 11/780 computers. This report describes the nominal TSAAS; other versions may have some unique features.

  9. Heat-Assisted Multiferroic Solid-State Memory.

    Science.gov (United States)

    Lepadatu, Serban; Vopson, Melvin M

    2017-08-25

    A heat-assisted multiferroic solid-state memory design is proposed and analysed, based on a PbNbZrSnTiO₃ antiferroelectric layer and Ni 81 Fe 19 magnetic free layer. Information is stored as magnetisation direction in the free layer of a magnetic tunnel junction element. The bit writing process is contactless and relies on triggering thermally activated magnetisation switching of the free layer towards a strain-induced anisotropy easy axis. A stress is generated using the antiferroelectric layer by voltage-induced antiferroelectric to ferroelectric phase change, and this is transmitted to the magnetic free layer by strain-mediated coupling. The thermally activated strain-induced magnetisation switching is analysed here using a three-dimensional, temperature-dependent magnetisation dynamics model, based on simultaneous evaluation of the stochastic Landau-Lifshitz-Bloch equation and heat flow equation, together with stochastic thermal fields and magnetoelastic contributions. The magnetisation switching probability is calculated as a function of stress magnitude and maximum heat pulse temperature. An operating region is identified, where magnetisation switching always occurs, with stress values ranging from 80 to 180 MPa, and maximum temperatures normalised to the Curie temperature ranging from 0.65 to 0.99.

  10. Solid state 13 C NMR quantitative study of wood tar pitches

    International Nuclear Information System (INIS)

    Prauchner, Marcos Juliano; Pasa, Vanya Marcia Duarte; Menezes, Sonia Maria Cabral de

    1999-01-01

    In this work, solid-state 13 C NMR is used with other techniques to characterize Eucalyptus tar pitches and to follow their polymerization reactions. The pitches are the residues of distillation (about 50% m;m) of the tar generated in Eucalyptus slow pyrolysis for charcoal production in metal industry

  11. Measurement of the Thermal Conductivity of Unfrozen and Frozen Food Materials by a Steady State Method with Coaxial Dual-cylinder Apparatus.

    Science.gov (United States)

    Pongsawatmanit, R; Miyawaki, O; Yano, T

    1993-01-01

    Coaxial dual-cylinder apparatus was used to measure the effective thermal conductivity of aqueous solutions of glucose, sucrose, gelatin and egg albumin over a temperature range from -20° to 20°C by the steady state method. The accuracy of the apparatus was confirmed by testing with water and ice. The effective thermal conductivity decreased with an increase in the total solid content in both the frozen and unfrozen states. In the unfrozen state, the effective thermal conductivity was slightly dependent on temperature. In the frozen state, however, the effective thermal conductivity was strongly dependent on temperature; lower temperatures gave higher effective thermal conductivity, reflecting the increase in the ice fration. For the unfrozen samples, the intrinsic thermal conductivity of each solid component was calculated by heat transfer models. All the models tested, series, parallel and Maxwell-Eucken, were equally applicable to describe the heat conduction in the unfrozen state. In the frozen state, however, the strong temperature dependency of the effective thermal conductivity suggests that the effect of the temperature dependency of the ice fraction should be incorporated into theoretical models.

  12. Einstein and solid-state physics

    International Nuclear Information System (INIS)

    Aut, I.

    1982-01-01

    A connection between the development of solid-state physics and the works and activity of Albert Einstein is traced. A tremendous Einstein contribution to solid state physics is marked. A strict establishment of particle-wave dualism; a conclusion about the applicability of the Plank radiation law not only to black body radiation; finding out particles indistinguishability - all three discoveries have a principle significance for solid state physics too

  13. Thermalization of squeezed states

    International Nuclear Information System (INIS)

    Solomon, Allan I

    2005-01-01

    Starting with a thermal squeezed state defined as a conventional thermal state based on an appropriate Hamiltonian, we show how an important physical property, the signal-to-noise ratio, is degraded, and propose a simple model of thermalization (Kraus thermalization)

  14. Thermal testing of solid neutron shielding materials

    International Nuclear Information System (INIS)

    Boonstra, R.H.

    1992-09-01

    Two legal-weight truck casks the GA-4 and GA-9, will carry four PWR and nine BWR spent fuel assemblies, respectively. Each cask has a solid neutron shielding material separating the steel body and the outer steel skin. In the thermal accident specified by NRC regulations in 10CFR Part 71, the cask is subjected to an 800 degree C environment for 30 minutes. The neutron shield need not perform any shielding function during or after the thermal accident, but its behavior must not compromise the ability of the cask to contain the radioactive contents. In May-June 1989 the first series of full-scale thermal tests was performed on three shielding materials: Bisco Products NS-4-FR, and Reactor Experiments RX-201 and RX-207. The tests are described in Thermal Testing of Solid Neutron Shielding Materials, GA-AL 9897, R. H. Boonstra, General Atomics (1990), and demonstrated the acceptability of these materials in a thermal accident. Subsequent design changes to the cask rendered these materials unattractive in terms of weight or adequate service temperature margin. For the second test series, a material specification was developed for a polypropylene based neutron shield with a softening point of at least 280 degree F. The neutron shield materials tested were boronated (0.8--4.5%) polymers (polypropylene, HDPE, NS-4). The Envirotech and Bisco materials are not polypropylene, but were tested as potential backup materials in the event that a satisfactory polypropylene could not be found

  15. Structural investigation of e-beam cured epoxy resins through solid state NMR

    International Nuclear Information System (INIS)

    Alessi, Sabina; Spinella, Alberto; Caponetti, Eugenio; Dispenza, Clelia; Spadaro, Giuseppe

    2012-01-01

    In this paper the network structure of e-beam cured DGEBF based epoxy resins is investigated. Two epoxy systems, having different reactivity and cured in different process conditions, were analyzed through solid state NMR spectroscopy. The analysis shows that the more reactive system has higher cross-linking density and higher uniformity of network distribution. Similar information were obtained, in a previous work, on the same systems through dynamic mechanical thermal analysis. It is worth noting that unlike DMTA tests, which interfere with the molecular structure of the analyzed material, due to the heating during the analysis itself, more reliable information, without any artefact, are obtained by solid state NMR, carried out at constant room temperature. - Highlights: ► The structure of two e-beam cured epoxy systems is investigated through solid state NMR. ► The aim is to have direct information about the structure without inducing modifications. ► The different molecular structures are able to emphasize the response of solid state NMR. ► T 1 H, T 1ρ H and T CH measurements indicate different cross-linking degrees. ► The NMR results are in agreement with DMTA analysis performed in a previous paper.

  16. Classical theory of thermal radiation from a solid.

    Science.gov (United States)

    Guo, Wei

    2016-06-01

    In this work, a solid at a finite temperature is modeled as an ensemble of identical atoms, each of which moves around a lattice site inside an isotropic harmonic potential. The motion of one such atom is studied first. It is found that the atom moves like a time-dependent current density and, thus, can emit electromagnetic radiation. Since all the atoms are identical, they can radiate, too. The resultant radiation from the atoms is the familiar thermal radiation from the solid. After its general expression is obtained, the intensity of the thermal radiation is discussed for its properties, and specifically calculated in the low-temperature limit. Both atomic motion and radiation are formulated in the classical domain.

  17. Solid state photodimerization in an organic salt of 1,2-bis(4-pyridyl ...

    Indian Academy of Sciences (India)

    Abdul Malik P Peedikakkal

    compound 1 undergoes photodimerization reaction in solid state to produce stereo-specific rctt-tetrakis(4- pyridyl)cyclobutane .... of isomers was calculated based on the integrated intensity of 1H NMR signals .... A combinatorial math- ematical ...

  18. Solid-state circuits

    CERN Document Server

    Pridham, G J

    2013-01-01

    Solid-State Circuits provides an introduction to the theory and practice underlying solid-state circuits, laying particular emphasis on field effect transistors and integrated circuits. Topics range from construction and characteristics of semiconductor devices to rectification and power supplies, low-frequency amplifiers, sine- and square-wave oscillators, and high-frequency effects and circuits. Black-box equivalent circuits of bipolar transistors, physical equivalent circuits of bipolar transistors, and equivalent circuits of field effect transistors are also covered. This volume is divided

  19. Interface reactions between Pd thin films and SiC by thermal annealing and SHI irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Njoroge, E.G., E-mail: eric.njoroge@up.ac.za [Department of Physics, University of Pretoria, Pretoria (South Africa); Theron, C.C. [Department of Physics, University of Pretoria, Pretoria (South Africa); Skuratov, V.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Wamwangi, D. [School of Physics, University of Witwatersrand, Johannesburg (South Africa); Hlatshwayo, T.T. [Department of Physics, University of Pretoria, Pretoria (South Africa); Comrie, C.M. [MRD, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); Malherbe, J.B. [Department of Physics, University of Pretoria, Pretoria (South Africa)

    2016-03-15

    The solid-state reactions between Pd thin films and 6H-SiC substrates induced by thermal annealing, room temperature swift heavy ion (SHI) irradiation and high temperature SHI irradiation have been investigated by in situ and real-time Rutherford backscattering spectrometry (RBS) and Grazing incidence X-ray diffraction (GIXRD). At room temperature, no silicides were detected to have formed in the Pd/SiC samples. Two reaction growth zones were observed in the samples annealed in situ and analysed by real time RBS. The initial reaction growth region led to formation of Pd{sub 3}Si or (Pd{sub 2}Si + Pd{sub 4}Si) as the initial phase(s) to form at a temperature of about 450 °C. Thereafter, the reaction zone did not change until a temperature of 640 °C was attained where Pd{sub 2}Si was observed to form in the reaction zone. Kinetic analysis of the initial reaction indicates very fast reaction rates of about 1.55 × 10{sup 15} at cm{sup −2}/s and the Pd silicide formed grew linear with time. SHI irradiation of the Pd/SiC samples was performed by 167 MeV Xe{sup 26+} ions at room temperature at high fluences of 1.07 × 10{sup 14} and 4 × 10{sup 14} ions/cm{sup 2} and at 400 °C at lower fluences of 5 × 10{sup 13} ions/cm{sup 2}. The Pd/SiC interface was analysed by RBS and no SHI induced diffusion was observed for room temperature irradiations. The sample irradiated at 400 °C, SHI induced diffusion was observed to occur accompanied with the formation of Pd{sub 4}Si, Pd{sub 9}Si{sub 2} and Pd{sub 5}Si phases which were identified by GIXRD analysis.

  20. Carbon doped lanthanum aluminate (LaAlO3:C) synthesized by solid state reaction for application in UV thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Alves, N.

    2015-01-01

    In this work we discuss the TL output for LaAlO 3 :C crystals grown by using three different combinations of Al 2 O 3 , La 2 O 3 and carbon atoms during the synthesis process. Recently, LaAlO 3 single crystals, co-doped with Ce 3+ and Dy 3+ rare earth trivalent ions and grown under hydrothermal conditions, have been reported to show high thermoluminescent response (TL) when exposed to low levels of ultraviolet radiation (UVR). However, undoped LaAlO 3 synthesized by solid state reaction method from the 1:1 mixture of aluminum and lanthanum oxide under reducing atmosphere revealed to have still higher thermoluminescent sensitivity to UV photon fields than the co-doped with Ce 3+ and Dy 3+ . It is well known that carbon doped aluminum oxide monocrystals have excellent TL and photoluminescent response properties for X-rays, UV and gamma radiation fields. Thus, we conducted three different syntheses of LaAlO 3 by this solid state reaction method, doping the mixture with carbon. The lanthanum aluminate polycrystals were synthesized from the 1:1 mixture of aluminum and lanthanum oxide, adding 0.1wt.% carbon and annealed at 1700°C for two hours in hydrogen atmosphere. The X-ray diffraction analysis revealed the formation of rhombohedral LaAlO 3 crystallographic phase, however a small percentage (15%) of Al 2 O 3 has been also identified. The UV-Vis absorbance spectra were obtained and F and F + - center were ascribed. The UV irradiations were carried out using a commercial 8W UV lamp. Thermoluminescence measurements were performed at a Harshaw 4500 TL reader. All compositions investigated have shown high TL sensitivity to UVR. (author)

  1. Synthesis and Characterization of Co (OH)2 Nanorods by Solid-state Chemical Reaction at Room Temperature%氢氧化钴纳米棒的室温固相化学合成及其表征

    Institute of Scientific and Technical Information of China (English)

    贾殿赠; 曹亚丽; 刘浪; 周杰; 肖定全

    2005-01-01

    Cobahous hydroxide nanorods were synthesized by solid-state chemical reactions of Co(Ac)2·4H2O, and NaOH at room temperature in the presence of polyethylene glycol 400 (PEG-400). The compositions and morphologies of the products were characterized by XRD, TEM, IR and TG-DTA. The results show that Co(OH)2 nanorods can be obtained only in one-step by means of surfactant-assisted soft-template solid-state chemical reaction method. The surfactant (PEG-400) plays a soft-template like role in the process of Co(OH)2 nanorods formation and leads nanocrystallines to grow along certain direction into nanorods.

  2. Heating-induced inner-sphere substitution and reduction-oxidation reactions of the solid phenanthroline containing cobalt (2) and cobalt (3) complexes

    International Nuclear Information System (INIS)

    Palade, D.M.

    1996-01-01

    The results of the differential thermal and thermogravimetric analyses of solid phenanthroline-containing complexes of cobalt (2) and cobalt (3) in the atmosphere of the air have been analyzed. Mechanism of redox reactions occurring when cobalt (3) complexes are heated has been discussed. It is shown that some of gaseous products of the redox processes appear as a result of secondary reactions and not the processes of the ligands oxidation by Co 3+ . The influence of certain inner-sphere and coordinated anions (of I, inclusively) on cobalt (3) complexes behaviour during heating has been considered

  3. Microstructure, ferromagnetic and photoluminescence properties of ITO and Cr doped ITO nanoparticles using solid state reaction

    Energy Technology Data Exchange (ETDEWEB)

    Babu, S. Harinath [Thin Films Laboratory, Centre for Crystal Growth, VIT University, Vellore-632014, Tamilnadu, India. (India); Kaleemulla, S., E-mail: skaleemulla@gmail.com [Thin Films Laboratory, Centre for Crystal Growth, VIT University, Vellore-632014, Tamilnadu, India. (India); Rao, N. Madhusudhana [Thin Films Laboratory, Centre for Crystal Growth, VIT University, Vellore-632014, Tamilnadu, India. (India); Rao, G. Venugopal [Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102, Tamilnadu (India); Krishnamoorthi, C. [Thin Films Laboratory, Centre for Crystal Growth, VIT University, Vellore-632014, Tamilnadu, India. (India)

    2016-11-01

    Indium-tin-oxide (ITO) (In{sub 0.95}Sn{sub 0.05}){sub 2}O{sub 3} and Cr doped indium-tin-oxide (In{sub 0.90}Sn{sub 0.05}Cr{sub 0.05}){sub 2}O{sub 3} nanoparticles were prepared using simple low cost solid state reaction method and characterized by different techniques to study their structural, optical and magnetic properties. Microstructures, surface morphology, crystallite size of the nanoparticles were studied using X-ray diffractometer (XRD), field emission scanning electron microscope (FE-SEM). From these methods it was found that the particles were about 45 nm. Chemical composition and valence states of the nanoparticles were studied using energy dispersive analysis of X-rays (EDAX) and X-ray photoelectron spectroscopy (XPS). From these techniques it was observed that the elements of indium, tin, chromium and oxygen were present in the system in appropriate ratios and they were in +3, +4, +3 and −2 oxidation states. Raman studies confirmed that the nanoparticle were free from unintentional impurities. Two broad emission peaks were observed at 330 nm and 460 nm when excited wavelength of 300 nm. Magnetic studies were carried out at 300 K and 100 K using vibrating sample magnetometer (VSM) and found that the ITO nanoparticles were ferromagnetic at 100 K and 300 K. Where-as the room temperature ferromagnetism completely disappeared in Cr doped ITO nanoparticles at 100 K and 300 K.

  4. A molecular dynamics study of thermal transport in nanoparticle doped Argon like solid

    Energy Technology Data Exchange (ETDEWEB)

    Shahadat, Muhammad Rubayat Bin, E-mail: rubayat37@gmail.com; Ahmed, Shafkat; Morshed, A. K. M. M. [Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka (Bangladesh)

    2016-07-12

    Interfacial phenomena such as mass and type of the interstitial atom, nano scale material defect influence heat transfer and the effect become very significant with the reduction of the material size. Non Equilibrium Molecular Dynamics (NEMD) simulation was carried out in this study to investigate the effect of the interfacial phenomena on solid. Argon like solid was considered in this study and LJ potential was used for atomic interaction. Nanoparticles of different masses and different molecular defects were inserted inside the solid. From the molecular simulation, it was observed that a large interfacial mismatch due to change in mass in the homogenous solid causes distortion of the phonon frequency causing increase in thermal resistance. Position of the doped nanoparticles have more profound effect on the thermal conductivity of the solid whereas influence of the mass ratio is not very significant. Interstitial atom positioned perpendicular to the heat flow causes sharp reduction in thermal conductivity. Structural defect caused by the molecular defect (void) also observed to significantly affect the thermal conductivity of the solid.

  5. New materials for solid state electrochemistry

    International Nuclear Information System (INIS)

    Ferloni, P.; Consiglio Nazionale delle Ricerche, Pavia; Magistris, A.; Consiglio Nazionale delle Ricerche, Pavia

    1994-01-01

    Solid state electrochemistry is an interdisciplinary area, undergoing nowadays a fast development. It is related on the one hand to chemistry, and on the other hand to crystallography, solid state physics and materials science. In this paper structural and electrical properties of some families of new materials interesting for solid state electrochemistry are reviewed. Attention is focused essentially on ceramic and crystalline materials, glasses and polymers, displaying high ionic conductivity and potentially suitable for various applications in solid state electrochemical devices. (orig.)

  6. Theoretical solid state physics

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Research activities at ORNL in theoretical solid state physics are described. Topics covered include: surface studies; particle-solid interactions; electronic and magnetic properties; and lattice dynamics

  7. Studies on reducing the thermal loads of solar-pumped solid state lasers; Taiyoko reiki laser no netsufuka teigen ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, K; Yugami, H; Naito, H; Arashi, H [Tohoku University, Sendai (Japan)

    1997-11-25

    It was intended to reduce the thermal loads of solar-pumped solid state lasers (highly densified solar light is irradiated directly onto a laser medium to cause excitation. No electric power is required for the excitation.). For this purpose, experiments were performed by using a selective permeation film. Solar light includes wavelengths not effective for excitation, which causes heat generation and thermal loads such as lens heating effect and thermal stress compounded refraction, degrading the laser beam quality. The Nd:YAG was used as a laser medium, and a multi-layered film (composed of SiO2 and TiO2) which cuts wavelength below 500 nm as a selective permeation film to cut light having wavelengths not required for excitation. A laser transmitting experiment revealed that the slope efficiency is improved by 27% as compared to not using the film. Beam fluctuation was improved to 45%. Using the selective permeation film has realized more efficient conversion of the solar light into a beam with better quality. The results for calculation of heat lens effect by using temperature distribution simulation showed good agreement with experimental values. Using the selective permeation film can suppress the maximum temperature of a laser rod to 68%, as well as the thermal stress. 9 figs., 2 tabs.

  8. Facile and efficient room temperature solid state reaction enabled synthesis of antimony nanoparticles embedded within reduced graphene oxide for enhanced sodium-ion storage

    Science.gov (United States)

    Zhang, Xiukui; Wu, Ping; Jiang, Li; Zhang, Xiaofang; Shi, Hongxia; Zhu, Xiaoshu; Wei, Shaohua; Zhou, Yiming

    2018-06-01

    Herein, a very simple and cost-effective solid state reaction method is employed to obtain, for the first time, the antimony nanoparticles embedded within reduced graphene oxide matrices (designated as Sb/rGO). By directly grinding antimony chloride and sodium hydroxide together at room temperature in the presence of graphene oxide (GO), Sb4O5Cl2 precursor was quickly obtained, which is evenly incorporated in the graphene oxide matrices. After subsequent chemical reduction by NaBH4, the Sb/rGO composite was successfully synthesized. The as-prepared Sb/rGO composite consists of uniform Sb nanoparticles of sub-20 nm, all of which have been wrapped in and protected by the rGO matrices. The Sb nanoparticles serve as a sufficient sodium ion reservoir while the rGO matrices provide highly efficient pathways for transport of sodium ions and electrons. Moreover, the volume expansion of Sb during sodiation can be buffered in the rGO matrices. As a result, the Sb/rGO composite exhibits excellent electrochemical performance in sodium-ion batteries (SIBs), including an enhanced cycling stability with a highly reversible charge capacity of 455 mA h g-1 after 45 cycles at 100 mA g-1, and a coulombic efficiency exceeding 98% during cycling. The findings in the present work pave the way to not only synthesize the designated promising electrode materials for high performance SIBs, but also thoroughly understand the solid-state reaction.

  9. Contribution to the modelling of gas-solid reactions and reactors

    International Nuclear Information System (INIS)

    Patisson, F.

    2005-09-01

    Gas-solid reactions control a great number of major industrial processes involving matter transformation. This dissertation aims at showing that mathematical modelling is a useful tool for both understanding phenomena and optimising processes. First, the physical processes associated with a gas-solid reaction are presented in detail for a single particle, together with the corresponding available kinetic grain models. A second part is devoted to the modelling of multiparticle reactors. Different approaches, notably for coupling grain models and reactor models, are illustrated through various case studies: coal pyrolysis in a rotary kiln, production of uranium tetrafluoride in a moving bed furnace, on-grate incineration of municipal solid wastes, thermogravimetric apparatus, nuclear fuel making, steel-making electric arc furnace. (author)

  10. Thermal transport across solid-solid interfaces enhanced by pre-interface isotope-phonon scattering

    Science.gov (United States)

    Lee, Eungkyu; Luo, Tengfei

    2018-01-01

    Thermal transport across solid interfaces can play critical roles in the thermal management of electronics. In this letter, we use non-equilibrium molecular dynamics simulations to investigate the isotope effect on the thermal transport across SiC/GaN interfaces. It is found that engineered isotopes (e.g., 10% 15N or 71Ga) in the GaN layer can increase the interfacial thermal conductance compared to the isotopically pure case by as much as 23%. Different isotope doping features, such as the isotope concentration, skin depth of the isotope region, and its distance from the interface, are investigated, and all of them lead to increases in thermal conductance. Studies of spectral temperatures of phonon modes indicate that interfacial thermal transport due to low-frequency phonons (transport. This work may provide insights into interfacial thermal transport and useful guidance to practical material design.

  11. Evolution of weak perturbations in gas-solid suspension with chemical reaction

    Energy Technology Data Exchange (ETDEWEB)

    Sharypov, O.V. [Russian Academy of Sciences, Novosibirsk (Russian Federation). Inst. of Thermophysics; Novosibirsk State Univ. (Russian Federation); Anufriev, I.S. [Novosibirsk State Univ. (Russian Federation)

    2013-07-01

    Dynamics of weak finite-amplitude perturbations in two-phase homogeneous medium (gas + solid particles) with non-equilibrium chemical reaction in gas is studied theoretically. Non-linear model of plane perturbation evolution is substantiated. The model takes into account wave-kinetic interaction and dissipation effects, including inter-phase heat and momentum transfer. Conditions for uniform state of the system are analyzed. Non-linear equation describing evolution of plane perturbation is derived under weak dispersion and dissipation effects. The obtained results demonstrate self-organization in the homogeneous system: steady-state periodic structure arises, its period, amplitude and velocity depends on the features of the medium. The dependencies of these parameters on dissipation and chemical kinetics are analyzed.

  12. All solid state pulsed power system for water discharge

    OpenAIRE

    Sakugawa, Takashi; Yamaguchi, Takahiro; Yamamoto, Kunihiro; Kiyan, Tsuyoshi; Namihira, Takao; Katsuki, Sunao; Akiyama, Hidenori; サクガワ, タカシ; ヤマグチ, タカヒロ; ヤマモト, クニヒロ; キヤン, ツヨシ; ナミヒラ, タカオ; カツキ, スナオ; アキヤマ, ヒデノリ; 佐久川, 貴志

    2005-01-01

    Pulsed power has been used to produce non-thermal plasmas in gases that generate a high electric field at the tip of streamer discharges, where high energy electrons, free radicals, and ozone are produced. Recently, all solid state pulsed power generators, which are operated with high repetition rate, long lifetime and high reliability, have been developed for industrial applications, such as high repetition rate pulsed gas lasers, high energy density plasma (EUV sources) and water discharges...

  13. Quantum Computing in Solid State Systems

    CERN Document Server

    Ruggiero, B; Granata, C

    2006-01-01

    The aim of Quantum Computation in Solid State Systems is to report on recent theoretical and experimental results on the macroscopic quantum coherence of mesoscopic systems, as well as on solid state realization of qubits and quantum gates. Particular attention has been given to coherence effects in Josephson devices. Other solid state systems, including quantum dots, optical, ion, and spin devices which exhibit macroscopic quantum coherence are also discussed. Quantum Computation in Solid State Systems discusses experimental implementation of quantum computing and information processing devices, and in particular observations of quantum behavior in several solid state systems. On the theoretical side, the complementary expertise of the contributors provides models of the various structures in connection with the problem of minimizing decoherence.

  14. Origin of stabilization and destabilization in solid-state redox reaction of oxide ions for lithium-ion batteries.

    Science.gov (United States)

    Yabuuchi, Naoaki; Nakayama, Masanobu; Takeuchi, Mitsue; Komaba, Shinichi; Hashimoto, Yu; Mukai, Takahiro; Shiiba, Hiromasa; Sato, Kei; Kobayashi, Yuki; Nakao, Aiko; Yonemura, Masao; Yamanaka, Keisuke; Mitsuhara, Kei; Ohta, Toshiaki

    2016-12-23

    Further increase in energy density of lithium batteries is needed for zero emission vehicles. However, energy density is restricted by unavoidable theoretical limits for positive electrodes used in commercial applications. One possibility towards energy densities exceeding these limits is to utilize anion (oxide ion) redox, instead of classical transition metal redox. Nevertheless, origin of activation of the oxide ion and its stabilization mechanism are not fully understood. Here we demonstrate that the suppression of formation of superoxide-like species on lithium extraction results in reversible redox for oxide ions, which is stabilized by the presence of relatively less covalent character of Mn 4+ with oxide ions without the sacrifice of electronic conductivity. On the basis of these findings, we report an electrode material, whose metallic constituents consist only of 3d transition metal elements. The material delivers a reversible capacity of 300 mAh g -1 based on solid-state redox reaction of oxide ions.

  15. Origin of stabilization and destabilization in solid-state redox reaction of oxide ions for lithium-ion batteries

    Science.gov (United States)

    Yabuuchi, Naoaki; Nakayama, Masanobu; Takeuchi, Mitsue; Komaba, Shinichi; Hashimoto, Yu; Mukai, Takahiro; Shiiba, Hiromasa; Sato, Kei; Kobayashi, Yuki; Nakao, Aiko; Yonemura, Masao; Yamanaka, Keisuke; Mitsuhara, Kei; Ohta, Toshiaki

    2016-01-01

    Further increase in energy density of lithium batteries is needed for zero emission vehicles. However, energy density is restricted by unavoidable theoretical limits for positive electrodes used in commercial applications. One possibility towards energy densities exceeding these limits is to utilize anion (oxide ion) redox, instead of classical transition metal redox. Nevertheless, origin of activation of the oxide ion and its stabilization mechanism are not fully understood. Here we demonstrate that the suppression of formation of superoxide-like species on lithium extraction results in reversible redox for oxide ions, which is stabilized by the presence of relatively less covalent character of Mn4+ with oxide ions without the sacrifice of electronic conductivity. On the basis of these findings, we report an electrode material, whose metallic constituents consist only of 3d transition metal elements. The material delivers a reversible capacity of 300 mAh g−1 based on solid-state redox reaction of oxide ions. PMID:28008955

  16. Solid state theory

    CERN Document Server

    Harrison, Walter A

    2011-01-01

    ""A well-written text . . . should find a wide readership, especially among graduate students."" - Dr. J. I. Pankove, RCA.The field of solid state theory, including crystallography, semi-conductor physics, and various applications in chemistry and electrical engineering, is highly relevant to many areas of modern science and industry. Professor Harrison's well-known text offers an excellent one-year graduate course in this active and important area of research. While presenting a broad overview of the fundamental concepts and methods of solid state physics, including the basic quantum theory o

  17. Solid-State Nanopore

    Directory of Open Access Journals (Sweden)

    Zhishan Yuan

    2018-02-01

    Full Text Available Abstract Solid-state nanopore has captured the attention of many researchers due to its characteristic of nanoscale. Now, different fabrication methods have been reported, which can be summarized into two broad categories: “top-down” etching technology and “bottom-up” shrinkage technology. Ion track etching method, mask etching method chemical solution etching method, and high-energy particle etching and shrinkage method are exhibited in this report. Besides, we also discussed applications of solid-state nanopore fabrication technology in DNA sequencing, protein detection, and energy conversion.

  18. Advances in simultaneous DSC-FTIR microspectroscopy for rapid solid-state chemical stability studies: some dipeptide drugs as examples.

    Science.gov (United States)

    Lin, Shan-Yang; Wang, Shun-Li

    2012-04-01

    The solid-state chemistry of drugs has seen growing importance in the pharmaceutical industry for the development of useful API (active pharmaceutical ingredients) of drugs and stable dosage forms. The stability of drugs in various solid dosage forms is an important issue because solid dosage forms are the most common pharmaceutical formulation in clinical use. In solid-state stability studies of drugs, an ideal accelerated method must not only be selected by different complicated methods, but must also detect the formation of degraded product. In this review article, an analytical technique combining differential scanning calorimetry and Fourier-transform infrared (DSC-FTIR) microspectroscopy simulates the accelerated stability test, and simultaneously detects the decomposed products in real time. The pharmaceutical dipeptides aspartame hemihydrate, lisinopril dihydrate, and enalapril maleate either with or without Eudragit E were used as testing examples. This one-step simultaneous DSC-FTIR technique for real-time detection of diketopiperazine (DKP) directly evidenced the dehydration process and DKP formation as an impurity common in pharmaceutical dipeptides. DKP formation in various dipeptides determined by different analytical methods had been collected and compiled. Although many analytical methods have been applied, the combined DSC-FTIR technique is an easy and fast analytical method which not only can simulate the accelerated drug stability testing but also at the same time enable to explore phase transformation as well as degradation due to thermal-related reactions. This technique offers quick and proper interpretations. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Determination of the percentage of quitine desacetilation reaction by solid state carbon-13 NMR

    International Nuclear Information System (INIS)

    Ferracin, Ricardo J.; Cass, Quezia B.; Bassi, Ana L.

    1997-01-01

    Quitine is a bi-polymer largely found in invertebrates. As most compounds of this class are insoluble in common organic solvents, the des-acetylation percentile was obtained by carbon-13 solid state nuclear magnetic resonance. The methodology is presented. Results are presented

  20. Thermal chemical-mechanical reactive flow model of shock initiation in solid explosives

    International Nuclear Information System (INIS)

    Nicholls, A.L. III; Tarver, C.M.

    1998-01-01

    The three dimensional Arbitrary Lagrange Eulerian hydrodynamic computer code ALE3D with fully coupled thermal-chemical-mechanical material models provides the framework for the development of a physically realistic model of shock initiation and detonation of solid explosives. The processes of hot spot formation during shock compression, subsequent ignition of reaction or failure to react, growth of reaction in individual hot spots, and coalescence of reacting hot spots during the transition to detonation can now be modeled using Arrhenius chemical kinetic rate laws and heat transfer to propagate the reactive flow. This paper discusses the growth rates of reacting hot spots in HMX and TATB and their coalescence during shock to detonation transition. Hot spot deflagration rates are found to be fast enough to consume explosive particles less than 10 mm in diameter during typical shock duration times, but larger particles must fragment and create more reactive surface area in order to be rapidly consumed

  1. Eutectic and solid-state wafer bonding of silicon with gold

    International Nuclear Information System (INIS)

    Abouie, Maryam; Liu, Qi; Ivey, Douglas G.

    2012-01-01

    Highlights: ► Eutectic and solid-state Au-Si bonding are compared for both a-Si and c-Si samples. ► Exchange of a-Si and Au layer was observed in both types of bonded samples. ► Use of c-Si for bonding resulted in formation of craters at the Au/c-Si interface. ► Solid-state Au-Si bonding produces better bonds in terms of microstructure. - Abstract: The simple Au-Si eutectic, which melts at 363 °C, can be used to bond Si wafers. However, faceted craters can form at the Au/Si interface as a result of anisotropic and non-uniform reaction between Au and crystalline silicon (c-Si). These craters may adversely affect active devices on the wafers. Two possible solutions to this problem were investigated in this study. One solution was to use an amorphous silicon layer (a-Si) that was deposited on the c-Si substrate to bond with the Au. The other solution was to use solid-state bonding instead of eutectic bonding, and the wafers were bonded at a temperature (350 °C) below the Au-Si eutectic temperature. The results showed that the a-Si layer prevented the formation of craters and solid-state bonding not only required a lower bonding temperature than eutectic bonding, but also prevented spill out of the solder resulting in strong bonds with high shear strength in comparison with eutectic bonding. Using amorphous silicon, the maximum shear strength for the solid-state Au-Si bond reached 15.2 MPa, whereas for the eutectic Au-Si bond it was 13.2 MPa.

  2. Low Temperature Solid-State Synthesis and Characterization of LaBO3

    Directory of Open Access Journals (Sweden)

    Azmi Seyhun KIPÇAK

    2016-11-01

    Full Text Available Rare earth (lanthanide series borates, possess high vacuum ultraviolet (VUV transparency, large electronic band gaps, chemical and environmental stability and exceptionally large optical damage thresholds and used in the development of plasma display panels (PDPs. In this study the synthesis of lanthanum borates via solid-state method is studied. For this purpose, lanthanum oxide (La2O3 and boric acid (H3BO3 are used for as lanthanum and boron sources, respectively. Different elemental molar ratios of La to B (between 3:1 to 1:6 as La2O3:H3BO3 were reacted by solid-state method at the reaction temperatures between 500°C - 700°C with the constant reaction time of 4 h. Following the synthesis, characterizations of the synthesized products are conducted by X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FT-IR, Raman spectroscopy and scanning electron microscope (SEM. From the results of the experiments, three types of lanthanum borates of; La3BO6, LaBO3 and La(BO23 were observed at different reaction parameters. Among these three types of lanthanum borates LaBO3 phase were obtained as a major phase.

  3. Solid state pump lasers with high power and high repetition rate

    International Nuclear Information System (INIS)

    Oba, Masaki; Kato, Masaaki; Arisawa, Takashi

    1995-01-01

    We built a laser diode pumped solid state green laser (LDPSSGL) rated at high repetition rate. Two laser heads are placed in one cavity with a rotator in between to design to avoid thermal lensing and thermal birefringence effect. Although average green laser power higher than 10 W was obtained at 1 kHz repetition rate with pulse width of 20-30 nsec, the beam quality was so much deteriorated that energy efficiency was as low as 2 %. Learning from this experience that high power oscillator causes a lot of thermal distortion not only in the laser rod but also in the Q-switch device, we proceeded to built a oscillator/amplifier system. A low power oscillator has a slab type crystal in the cavity. As a result spatial distribution of laser power was extremely improved. As we expect that the high repetition rate solid state laser should be CW operated Q-switch type laser from the view point of lifetime of diode lasers, a conventional arc lamp pumped CW Q-switch green YAG laser of which the repetition rate is changeable from 1 kHz to 5 kHz and the pulse width is 250-570 nsec was also tested to obtain pumping characteristics of a dye laser as a function of power, pulse width etc., and dye laser pulse width of 100-130 nsec were obtained. (author)

  4. A model for a countercurrent gas—solid—solid trickle flow reactor for equilibrium reactions. The methanol synthesis

    NARCIS (Netherlands)

    Westerterp, K.R.; Kuczynski, M.

    1987-01-01

    The theoretical background for a novel, countercurrent gas—solid—solid trickle flow reactor for equilibrium gas reactions is presented. A one-dimensional, steady-state reactor model is developed. The influence of the various process parameters on the reactor performance is discussed. The physical

  5. A miniature CSTR cascade for continuous flow of reactions containing solids

    OpenAIRE

    Mo, Yiming; Jensen, Klavs F

    2016-01-01

    Continuous handling of solids creates challenges for realizing continuous production of pharmaceuticals and fine chemicals. We present a new miniature continuous stirred-tank reactor (CSTR) cascade to handle solid-forming reactions in flow. Single-phase residence time distribution (RTD) measurements of the CSTR cascade reveal nearly ideal CSTR mixing behavior of the individual units. Consistency of experimental and predicted conversions of a Diels–Alder reaction further confirms the CSTR perf...

  6. Solid-state synthesis of Li{sub 4}Ti{sub 5}O{sub 12} whiskers from TiO{sub 2}-B

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Wenjun [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 Xin Mofan Road, Nanjing 210009 (China); Zhuang, Wei [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 Xin Mofan Road, Nanjing 210009 (China); College of Biotechnology and Pharmaceutical Engineering, National Engineering Technique Research Center for Biotechnology, Nanjing Tech University, No. 30, Puzhu South Road, Nanjing 211816 (China); Ji, Xiaoyan [Division of Energy Science/Energy Engineering, Luleå University of Technology, Luleå 97187 Sweden (Sweden); Chen, Jingjing; Lu, Xiaohua [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 Xin Mofan Road, Nanjing 210009 (China); Wang, Changsong, E-mail: wcs@njtech.edu.cn [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 Xin Mofan Road, Nanjing 210009 (China)

    2016-03-15

    Highlights: • The Li{sub 4}Ti{sub 5}O{sub 12} whiskers were synthesized from TiO{sub 2}-B whiskers via a solid state reaction. • The TiO{sub 2}-B crystal structure for lithium diffusion is easier than anatase. • The separated diffusion and reaction process is crucial for the solid-state syntheses of Li{sub 4}Ti{sub 5}O{sub 12} whiskers. - Abstract: In this work, Li{sub 4}Ti{sub 5}O{sub 12} (LTO) was synthesized from the precursors of TiO{sub 2}-B and anatase whiskers, respectively. The synthesized LTO whiskers from TiO{sub 2}-B whiskers via a solid state reaction at 650 °C have a high degree of crystallinity with an average diameter of 300 nm. However, when anatase whiskers were used as the precursor, only particle morphology LTO was produced at 750 °C. The further analysis of the precursors, the intermediate products and the final products reveal that the crystal structure of the anatase hinders the diffusion of lithium, leading to a typical reaction–diffusion process. Under this condition, only particle morphology LTO can be produced. However, the crystal structure of the TiO{sub 2}-B is easy for lithium diffusion and the process is performed in two separated steps (i.e., diffusion and reaction), which makes it possible to decrease the solid-state reaction temperature down to 650 °C and then maintain the morphologies of whiskers.

  7. Chemical cleavage reactions of DNA on solid support: application in mutation detection

    Directory of Open Access Journals (Sweden)

    Cotton Richard GH

    2003-05-01

    Full Text Available Abstract Background The conventional solution-phase Chemical Cleavage of Mismatch (CCM method is time-consuming, as the protocol requires purification of DNA after each reaction step. This paper describes a new version of CCM to overcome this problem by immobilizing DNA on silica solid supports. Results DNA test samples were loaded on to silica beads and the DNA bound to the solid supports underwent chemical modification reactions with KMnO4 (potassium permanganate and hydroxylamine in 3M TEAC (tetraethylammonium chloride solution. The resulting modified DNA was then simultaneously cleaved by piperidine and removed from the solid supports to afford DNA fragments without the requirement of DNA purification between reaction steps. Conclusions The new solid-phase version of CCM is a fast, cost-effective and sensitive method for detection of mismatches and mutations.

  8. Uranium isotope separation in the solid state. Progress report, December 1, 1976--June 1, 1977

    International Nuclear Information System (INIS)

    Bernstein, E.R.

    1977-06-01

    Since we were actively able to work on this project, we have been engaged in three separate lines of research. Each of these has been related to laser-induced isotope separation of uranium in the solid state. The three areas are: (a) improved reaction chemistry for both host materials Zr(BH 4 ) 4 and Hf(BH 4 ) 4 and U(BH 4 ) 4 itself; (b) improved spectroscopic techniques in order to obtain sharper spectra; and (c) solid state photochemical investigations to study U(BH 4 ) 4 photodecomposition mechanism and yield as a function of wave length. These are all integral parts of the solid state isotope separation procedure and are discussed in terms of the overall process proposed

  9. Numerical Simulations of Pillar Structured Solid State Thermal Neutron Detector Efficiency and Gamma Discrimination

    Energy Technology Data Exchange (ETDEWEB)

    Conway, A; Wang, T; Deo, N; Cheung, C; Nikolic, R

    2008-06-24

    This work reports numerical simulations of a novel three-dimensionally integrated, {sup 10}boron ({sup 10}B) and silicon p+, intrinsic, n+ (PIN) diode micropillar array for thermal neutron detection. The inter-digitated device structure has a high probability of interaction between the Si PIN pillars and the charged particles (alpha and {sup 7}Li) created from the neutron - {sup 10}B reaction. In this work, the effect of both the 3-D geometry (including pillar diameter, separation and height) and energy loss mechanisms are investigated via simulations to predict the neutron detection efficiency and gamma discrimination of this structure. The simulation results are demonstrated to compare well with the measurement results. This indicates that upon scaling the pillar height, a high efficiency thermal neutron detector is possible.

  10. Applications of solid-state nuclear track detectors (SSNTDs) for fast ion and fusion reaction product measurements in TEXTOR experiments

    Energy Technology Data Exchange (ETDEWEB)

    Szydlowski, A.; Malinowski, K.; Malinowska, A. [Association EURTOM-IPPLM Warsaw, The Andrzej Soltan Institute for Nuclear Studies, 05-400 Otwock-Swierk (Poland); Wassenhove, G. Van [EURATOM-Belgium State Association, LPP, ERM/KMS, Trilateral Euregio Cluster, B-1000 Brussels (Belgium); Schweer, B. [Association EURATOM-FZJ, Institutte of Plasma Physicx, Juelich (Germany)

    2011-07-01

    Full text of publication follows: The paper reports on measurements of fusion reaction protons which were performed on TEXTOR facility in January 2009. The basic experimental scheme was similar to that applied in the previous measurements [1, 2]. The main experimental tool equipment was a small ion pinhole camera which was equipped with a PM-355 detector sample and was attached to a water cooled manipulator. The camera was placed below the plasma ring in the direction of ion drifts, at a distance of 4.4 cm from LCFS. However, in the described experiment it was aligned at an angle to the mayor TEXTOR radius (contrary to previous experiments), so that the input pinhole was oriented first at {gamma} = 45 degrees (shots 108799 - 108818) and then {gamma} = 600 (shots 108832 - 108847). The discharges were executed with one neutral beam of the total power 0.6 - 1.0 MW. In the first series (Nos 108799 - 108818) the plasma was additionally heated by ICRH of frequency 38 MHz. The irradiated detector samples were subjected to the same interrupted etching procedure as the samples used in the CR-39/PM-355 detector calibration measurements [1, 2]. After that, track density distributions and track diameter histograms were measured under an optical microscope. By the use of the calibration curves, it was possible to distinguish craters produced by protons from other craters and to convert the obtained histograms into proton energy spectra. The craters induced by lower energy ions appeared to be concentrated in narrower areas, whereas higher energy ions were registered in a more diffused detector fields. The paper shows again that the CR-39/PM-355 detector is an useful diagnostic tool for tokamak experiments, for measurement of charged ions. References: [1] A. Szydlowski, A. Malinowska, M. Jaskola, A. Korman, M.J. Sadowski, G. Van Wassenhove, B. Schweer and the TEXTOR team, A. Galkowski, 'Application of Solid State Nuclear Track Detectors in TEXTOR Experiment for Measurements

  11. Micron-sized columnar grains of CH3NH3PbI3 grown by solvent-vapor assisted low-temperature (75 °C) solid-state reaction: The role of non-coordinating solvent-vapor

    Science.gov (United States)

    Zheng, Huifeng; Liu, Yangqiao; Sun, Jing

    2018-04-01

    The preparation of hybrid perovskite films with large columnar grains via low-temperature solid-state reaction remains a big challenge. Conventional solvent annealing using DMF, DMSO and ethanol, etc. fails to work effectively at low temperature (solar cells based on benzyl-alcohol-vapor annealing (75 °C), delivered much higher photovoltaic performance, better stability and smaller hysteresis than those based on conventional thermal annealing. Additionally, a champion power conversion efficiency (PCE) of 15.1% was obtained and the average PCE reached 12.2% with a tiny deviation. Finally, the mechanism of solvent annealing with non-coordinating solvent was discussed. Moreover, we revealed that high polarity and high boiling point of the solvent used for generating vapor, was critical to grow micron-sized columnar grains at such a low temperature (75 °C). This work will contribute to understanding the mechanism of grain growth in solvent annealing and improving its facility and effectiveness.

  12. Solid state chemistry of rare earth oxides. Final report, September 1, 1950--July 31, 1977

    International Nuclear Information System (INIS)

    Eyring, L.

    1977-07-01

    Work under Contract E(11-1)-1109 and its antecedents has been primarily for the purpose of obtaining detailed thermodynamic, kinetic and structural information on the complex rare earth oxides of praseodymium and terbium. These systems exhibit homologous series of ordered phases, order-disorder transformations, wide-range nonstoichiometric phases, chemical hysteresis in two-phase regions and many other solid state reaction phenomena. Fluorite-related materials of importance to ERDA occur as nuclear fuels, radiation power sources, insulators and solid electrolytes. The rare earth oxides serve directly as model systems for such similar materials and, in a more general sense, they serve as models of solids in general since they exhibit nearly the full range of solid state properties

  13. On the sensitivity of FPPE - TWRC method in thermal effusivity investigations of solids

    International Nuclear Information System (INIS)

    Dadarlat, Dorin; Streza, Mihaela; Pop, Mircea N; Tosa, Valer

    2009-01-01

    The front detection configuration (FPPE) together with the thermal-wave-resonator-cavity (TWRC) method was used for direct measurement of the thermal effusivity of solid materials inserted as backings in the FPPE detection cell. It was demonstrated that the normalized phase of the FPPE signal has an oscillating dependence as a function of sample's thickness. The paper presents experimental results on solid materials, with various values of thermal effusivity (Cu, brass, steel, bakelite, wood). A study of the sensitivity of the technique for different liquid/backing effusivity ratios is performed. The highest sensitivity was obtained when investigating solids with values of thermal effusivity not far from the effusivity of the liquid layer of the detection cell.

  14. Thermal conductivities of (ZrxPu(1-x)/2Am(1-x)/2)N solid solutions

    International Nuclear Information System (INIS)

    Nishi, Tsuyoshi; Takano, Masahide; Akabori, Mitsuo; Arai, Yasuo

    2011-01-01

    The thermal conductivity of Zr-based transuranium (TRU) nitride solid solutions is important for designing subcritical cores in nitride-fueled ADS. Some results have been reported concerning the thermal conductivities of (Zr,Pu)N. However, there have been no experimental data on the thermal conductivities of Zr-based nitride solid solutions containing MA. In this study, the authors prepared sintered samples of (Zr x Pu (1-x)/2 Am (1-x)/2) N (x=0.0, 0.58, 0.80) solid solutions. The thermal diffusivity and heat capacity of (Zr x Pu (1-x)/2 Am (1-x)/2) N solid solutions were measured using a laser flash method and drop calorimetry, respectively. Thermal conductivities were determined from the measured thermal diffusivities, heat capacities and bulk densities over a temperature range of 473 to 1473 K. The thermal conductivities of (Zr 0.58 Pu 0.21 Am 0.21 )N and (Zr 0.80 Pu 0.10 Am 0.10 )N solid solutions were found to be higher than that of (Pu 0.5 Am 0.5 )N due to the high thermal conductivity of ZrN as the principal component, although they were lower than that of ZrN due to the impurifying effect of the transuranium elements. Thus, the thermal conductivities of (Zr x Pu (1-x)/2 Am (1-x)/2) N solid solutions increased with increasing ZrN concentration. Moreover, in order to help to promote the design study of nitride-fueled ADS, the thermal conductivity of the (Zr x Pu (1-x)/2 Am (1-x)/2) N solid solutions were fitted to an equation using the least squares method. (author)

  15. Solid-state devices and applications

    CERN Document Server

    Lewis, Rhys

    1971-01-01

    Solid-State Devices and Applications is an introduction to the solid-state theory and its devices and applications. The book also presents a summary of all major solid-state devices available, their theory, manufacture, and main applications. The text is divided into three sections. The first part deals with the semiconductor theory and discusses the fundamentals of semiconductors; the kinds of diodes and techniques in their manufacture; the types and modes of operation of bipolar transistors; and the basic principles of unipolar transistors and their difference with bipolar transistors. The s

  16. The physics of solid-state neutron detector materials and geometries.

    Science.gov (United States)

    Caruso, A N

    2010-11-10

    Detection of neutrons, at high total efficiency, with greater resolution in kinetic energy, time and/or real-space position, is fundamental to the advance of subfields within nuclear medicine, high-energy physics, non-proliferation of special nuclear materials, astrophysics, structural biology and chemistry, magnetism and nuclear energy. Clever indirect-conversion geometries, interaction/transport calculations and modern processing methods for silicon and gallium arsenide allow for the realization of moderate- to high-efficiency neutron detectors as a result of low defect concentrations, tuned reaction product ranges, enhanced effective omnidirectional cross sections and reduced electron-hole pair recombination from more physically abrupt and electronically engineered interfaces. Conversely, semiconductors with high neutron cross sections and unique transduction mechanisms capable of achieving very high total efficiency are gaining greater recognition despite the relative immaturity of their growth, lithographic processing and electronic structure understanding. This review focuses on advances and challenges in charged-particle-based device geometries, materials and associated mechanisms for direct and indirect transduction of thermal to fast neutrons within the context of application. Calorimetry- and radioluminescence-based intermediate processes in the solid state are not included.

  17. PERFORMANCE OPTIMIZATION OF THE DIODE-PUMPED SOLID-STATE LASER FOR SPACE APPLICATIONS

    Directory of Open Access Journals (Sweden)

    D. A. Arkhipov

    2015-11-01

    Full Text Available Subject of Research. Thermophysical and optical techniques of parameter regulation for diode pumped solid-state laser are studied as applied to space laser communication and laser ranging lines. Methods. The investigations are carried out on the base of the original design of diode pumped solid-state laser module that includes the following: Nd:YAG slab element, diode pumped by 400W QCW produced by NORTHROP GRUMMAN; two-pass unstable resonator with rotation of the laser beam aperture about its axis through 1800; the output mirror of the resonator with a variable reflection coefficient; hyperthermal conductive plates for thermal stabilization of the laser diode generation modes. The presence of thermal conductive plates excludes conventional running water systems applied as cooling systems for solid-state laser components. The diodes temperature stabilization is achieved by applying the algorithm of pulse-width modulation of power of auxiliary electric heaters. To compensate for non-stationary thermal distortions of the slab refractive index, the laser resonator scheme comprises a prism reflector with an apex angle of 1200. Narrow sides of the prism are covered with reflective coating, and its wide side is sprayed with antireflection coating. The beam aperture is turned around its axis through 1800 because of triple reflection of the beam inside the prism. The turning procedure leads to compensating for the output beam phase distortions in view of symmetric character of the aberrations of slab refractive index. To suppress parasitic oscillations inside the slab, dielectric coatings of wide sides of the slab are used. Main Results. We have demonstrated theoretically and experimentally that the usage of hyperthermal conductive plates together with the algorithm of pulse-width modulation provides stabilizing of the diode substrate temperature accurate within ± 0.1 °С and smoothing the temperature distribution along the plate surface accurate

  18. Characterising of solid state electrochemical cells under operation

    DEFF Research Database (Denmark)

    Holtappels, Peter

    2014-01-01

    Compared to significant progress in PEMFC especially regarding the utilization of complex fuels such as methanol significant progress has been made by applying spectroscopic / differential IR and spectrometric techniques to working fuel cells, the processes in solid state high temperature...... electrochemical cells are still a "black box". In order to identify local reaction sites, surface coverage and potential/current introduced materials and surface modifications, in situ techniques are needed to gain a better understanding of the elementary and performance limiting steps for these cells...

  19. Solid-state polymeric dye lasers

    CERN Document Server

    Singh, S; Sridhar, G; Muthuswamy, V; Raja, K

    2003-01-01

    This paper presents a review of the organic solid-state polymer materials, which have become established as a new laser media. The photostability of these materials is discussed. Different types of solid-state lasers built around these materials are also reviewed.

  20. Solid State Self-Healing System: Effects of Using Immiscible Healing Agents

    International Nuclear Information System (INIS)

    Noor Nabilah Muhamad; Mohd Suzeren Mohd Jamil

    2015-01-01

    The solid state self-healing system was obtained by employs a thermosetting epoxy resin, into which a thermoplastic is dissolved. The aim of this study is to identify the effect of using immiscible healing agents, which are polyvinyl chloride and polyvinyl alcohol, on solid state self-healing system. Healing was achieved by heating the fractured resins to a specific temperature; above their glass transition temperature (Tg) which obtained from dynamic mechanical analysis (DMA) in order for thermal expansion to occur. The thermal properties and bonding formed in the epoxy resins were characterized by means of Fourier Transform Infrared Spectroscopy (FTIR). Izod impact test was performed in preliminary work. Further work then has been done using compact tension test to demonstrate details self-healing capability of the different specimens. Under compact tension test, it was found that healable resin with PVC has highest healing efficiency followed PVA with 7.4 % and 3 % of average percentage healing efficiencies respectively. These results are due to the different solubility parameters of the thermoset/ network and thermoplastic polymer which led to the phase separation. Morphological studies using microscope optic prove the fracture-healing process and morphological properties of the resins. (author)

  1. Environmental performance evaluation of an advanced-design solid-state television camera

    Science.gov (United States)

    1979-01-01

    The development of an advanced-design black-and-white solid-state television camera which can survive exposure to space environmental conditions was undertaken. A 380 x 488 element buried-channel CCD is utilized as the image sensor to ensure compatibility with 525-line transmission and display equipment. Specific camera design approaches selected for study and analysis included: (1) component and circuit sensitivity to temperature; (2) circuit board thermal and mechanical design; and (3) CCD temperature control. Preferred approaches were determined and integrated into the final design for two deliverable solid-state TV cameras. One of these cameras was subjected to environmental tests to determine stress limits for exposure to vibration, shock, acceleration, and temperature-vacuum conditions. These tests indicate performance at the design goal limits can be achieved for most of the specified conditions.

  2. Analysis of thermal expansivity of solids at extreme compression

    Directory of Open Access Journals (Sweden)

    J. Shanker

    2008-12-01

    Full Text Available Thermodynamics of solids in the limit of infinite pressure formulated by Stacey reveals that the thermal expansivity (alpha of solids tends to zero at infinite pressure. The earlier models for the volume dependence of thermal expansivity do not satisfy the infinite pressure behaviour of thermal expansivity. The expressions for the volume dependence of the isothermal Anderson- Grüneisen parameter (delta T considered in the derivation of earlier formulations for alpha (V have been found to be inadequate. A formulation for the volume dependence of delta T is presented here which is similar to the model due to Burakovsky and Preston for the volume dependence of the Grüneisen parameter. The new formulation for alpha (V reveals that delta T infinity must be greater than zero for satisfying the thermodynamic result according to which alpha tends to zero at infinite pressure. It is found that our model fits well the experimental data on thermal expansivity alpha (V for hcp iron corresponding to a wide range of pressures (0-360 GPa.

  3. Gas-Solid Reaction Route toward the Production of Intermetallics from Their Corresponding Oxide Mixtures

    Directory of Open Access Journals (Sweden)

    Hesham Ahmed

    2016-08-01

    Full Text Available Near-net shape forming of metallic components from metallic powders produced in situ from reduction of corresponding pure metal oxides has not been explored to a large extent. Such a process can be probably termed in short as the “Reduction-Sintering” process. This methodology can be especially effective in producing components containing refractory metals. Additionally, in situ production of metallic powder from complex oxides containing more than one metallic element may result in in situ alloying during reduction, possibly at lower temperatures. With this motivation, in situ reduction of complex oxides mixtures containing more than one metallic element has been investigated intensively over a period of years in the department of materials science, KTH, Sweden. This review highlights the most important features of that investigation. The investigation includes not only synthesis of intermetallics and refractory metals using the gas solid reaction route but also study the reaction kinetics and mechanism. Environmentally friendly gases like H2, CH4 and N2 were used for simultaneous reduction, carburization and nitridation, respectively. Different techniques have been utilized. A thermogravimetric analyzer was used to accurately control the process conditions and obtain reaction kinetics. The fluidized bed technique has been utilized to study the possibility of bulk production of intermetallics compared to milligrams in TGA. Carburization and nitridation of nascent formed intermetallics were successfully carried out. A novel method based on material thermal property was explored to track the reaction progress and estimate the reaction kinetics. This method implies the dynamic measure of thermal diffusivity using laser flash method. These efforts end up with a successful preparation of nanograined intermetallics like Fe-Mo and Ni-W. In addition, it ends up with simultaneous reduction and synthesis of Ni-WN and Ni-WC from their oxide mixtures

  4. Organic solid-state lasers

    CERN Document Server

    Forget, Sébastien

    2013-01-01

    Organic lasers are broadly tunable coherent sources, potentially compact, convenient and manufactured at low-costs. Appeared in the mid 60’s as solid-state alternatives for liquid dye lasers, they recently gained a new dimension after the demonstration of organic semiconductor lasers in the 90's. More recently, new perspectives appeared at the nanoscale, with organic polariton and surface plasmon lasers. After a brief reminder to laser physics, a first chapter exposes what makes organic solid-state organic lasers specific. The laser architectures used in organic lasers are then reviewed, with a state-of-the-art review of the performances of devices with regard to output power, threshold, lifetime, beam quality etc. A survey of the recent trends in the field is given, highlighting the latest developments with a special focus on the challenges remaining for achieving direct electrical pumping of organic semiconductor lasers. A last chapter covers the applications of organic solid-state lasers.

  5. Solid-state synthesis, structure and properties of a novel open-framework cadmium selenite bromide: [Cd10(SeO3)8Br4]·HBr·H2O

    International Nuclear Information System (INIS)

    Chen, Wen-Tong; Wang, Ming-Sheng; Wang, Guan-E; Chen, Hui-Fen; Guo, Guo-Cong

    2013-01-01

    A novel open-framework cadmium selenite bromide, [Cd 10 (SeO 3 ) 8 Br 4 ]·HBr·H 2 O (1), has been obtained by a solid-state reaction at 450 °C, and the structure has been determined by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in Pbcm of the orthorhombic system: a=10.882(3), b=16.275(5), c=18.728(6) Å, V=3317(2) Å 3 , R1/wR2=0.0411/0.0659. Compound 1 is characteristic of a novel 3-D open-framework structure, composing ∞ 2 [CdSeO 3 ] layers and the pillars of edge-shared CdO 3 Br 2 square pyramids. The lattice water molecules and the HBr molecules locate in the voids of the framework. Optical absorption spectrum of 1 reveals the presence of an optical gap of 1.65 eV. Solid-state photoluminescent study indicates that compound 1 exhibits strong violet emission. TG–DSC measurement shows that compound 1 is thermally stable up to 200 °C. - Graphical abstract: A metal selenite halide has been synthesized and features a 3-D open-framework structure, composing edge-shared CdO 8 decahedra and pillars of edge-sharing pentahedra. UV–vis, TG–DSC and luminescent measurements are also reported. Highlights: • This paper reports a novel cadmium selenite bromide obtained by an intermediate-temperature solid-state reaction. • The title compound is characteristic of a novel 3-D open-framework structure, composing ∞ 2 [CdSeO 3 ] layers and the pillars of edge-shared CdO 3 Br 2 square pyramids. • The title compound is thermally stable up to 200 °C. • The title compound has an optical gap of 1.65 eV and exhibits strong violet emission

  6. Cu2Se and Cu Nanocrystals as Local Sources of Copper in Thermally Activated In Situ Cation Exchange

    KAUST Repository

    Casu, Alberto; Genovese, Alessandro; Manna, Liberato; Longo, Paolo; Buha, Joka; Botton, Gianluigi A.; Lazar, Sorin; Kahaly, M. Upadhyay; Schwingenschlö gl, Udo; Prato, Mirko; Li, Hongbo; Ghosh, Sandeep; Palazon, Francisco; De Donato, Francesco; Lentijo Mozo, Sergio; Zuddas, Efisio; Falqui, Andrea

    2016-01-01

    Among the different synthesis approaches to colloidal nanocrystals a recently developed toolkit is represented by cation exchange reactions, where the use of template nanocrystals gives access to materials that would be hardly attainable via direct synthesis. Besides, post-synthetic treatments, such as thermally activated solid state reactions, represent a further flourishing route to promote finely controlled cation exchange. Here, we report that, upon in situ heating in a transmission electron microscope, Cu2Se nanocrystals deposited on an amorphous solid substrate undergo partial loss of Cu atoms, which are then engaged in local cation exchange reactions with Cu “acceptors” phases represented by rod- and wire- shaped CdSe nanocrystals. This thermal treatment slowly transforms the initial CdSe nanocrystals into Cu2-xSe nanocrystals, through the complete sublimation of Cd and the partial sublimation of Se atoms. Both Cu “donor” and “acceptor” particles were not always in direct contact with each other, hence the gradual transfer of Cu species from Cu2Se or metallic Cu to CdSe nanocrystals was mediated by the substrate and depended on the distance between the donor and acceptor nanostructures. Differently from what happens in the comparably faster cation exchange reactions performed in liquid solution, this study shows that slow cation exchange reactions can be performed at the solid state, and helps to shed light on the intermediate steps involved in such reactions.

  7. Cu2Se and Cu Nanocrystals as Local Sources of Copper in Thermally Activated In Situ Cation Exchange

    KAUST Repository

    Casu, Alberto

    2016-01-27

    Among the different synthesis approaches to colloidal nanocrystals a recently developed toolkit is represented by cation exchange reactions, where the use of template nanocrystals gives access to materials that would be hardly attainable via direct synthesis. Besides, post-synthetic treatments, such as thermally activated solid state reactions, represent a further flourishing route to promote finely controlled cation exchange. Here, we report that, upon in situ heating in a transmission electron microscope, Cu2Se nanocrystals deposited on an amorphous solid substrate undergo partial loss of Cu atoms, which are then engaged in local cation exchange reactions with Cu “acceptors” phases represented by rod- and wire- shaped CdSe nanocrystals. This thermal treatment slowly transforms the initial CdSe nanocrystals into Cu2-xSe nanocrystals, through the complete sublimation of Cd and the partial sublimation of Se atoms. Both Cu “donor” and “acceptor” particles were not always in direct contact with each other, hence the gradual transfer of Cu species from Cu2Se or metallic Cu to CdSe nanocrystals was mediated by the substrate and depended on the distance between the donor and acceptor nanostructures. Differently from what happens in the comparably faster cation exchange reactions performed in liquid solution, this study shows that slow cation exchange reactions can be performed at the solid state, and helps to shed light on the intermediate steps involved in such reactions.

  8. Synthesis, characterization and thermal expansion studies on thorium-praseodymium mixed oxide solid solutions

    International Nuclear Information System (INIS)

    Panneerselvam, G.; Antony, M.P.; Srinivasan, T.G.; Vasudeva Rao, P.R.

    2010-01-01

    Full text: Thorium-praseodymium mixed oxide solid solutions containing 15, 25, 40 and 55 mole percent of praseodymia were synthesized by mixing the solutions of thorium nitrate in water and praseodymium oxide (Pr 6 O 11 ) in conc. HNO 3 . Subsequently, their hydroxides were co-precipitated by the addition of aqueous ammonia. Further the precipitate was dried at 50 deg C, calcined at 600 deg C for 4 hours and sintered at 1200 deg C for 6 h in air. X-ray diffraction measurements were performed for phase identification and lattice parameter derivation. Single-phase fluorite structure was observed for all the compositions. Bulk and theoretical densities of solid solutions were also determined by immersion and X-ray techniques. Thermal expansion coefficients and percentage linear thermal expansion of the solid solutions were determined using high temperature X-ray diffraction technique in the temperature range 300 to 1700 K for the first time. The room temperature lattice constants estimated for above compositions are 0.5578, 0.5565, 0.5545 and 0.5526 nm, respectively. The mean linear thermal expansion coefficients for the solid solutions are 15.48 x 10 -6 K -1 , 18.35 x 10 -6 K -1 , 22.65 x 10 -6 K -1 and 26.95 x 10 -6 K -1 , respectively. The percentage linear thermal expansions in this temperature range are 1.68, 1.89, 2.21 and 2.51 respectively. It is seen that the solid solutions are stable up to 1700 K. It is also seen that the effect and nature of the dopant are the important parameters influencing the thermal expansion of the ThO 2 . The lattice parameter of the solid solutions exhibited a decreasing trend with respect to praseodymia addition. The percentage linear thermal expansion of the solid solutions increases steadily with increasing temperature

  9. Gas-Solid Reaction Properties of Fluorine Compounds and Solid Adsorbents for Off-Gas Treatment from Semiconductor Facility

    Directory of Open Access Journals (Sweden)

    Shinji Yasui

    2012-01-01

    Full Text Available We have been developing a new dry-type off-gas treatment system for recycling fluorine from perfluoro compounds present in off-gases from the semiconductor industry. The feature of this system is to adsorb the fluorine compounds in the exhaust gases from the decomposition furnace by using two types of solid adsorbents: the calcium carbonate in the upper layer adsorbs HF and converts it to CaF2, and the sodium bicarbonate in the lower layer adsorbs HF and SiF4 and converts them to Na2SiF6. This paper describes the fluorine compound adsorption properties of both the solid adsorbents—calcium carbonate and the sodium compound—for the optimal design of the fixation furnace. An analysis of the gas-solid reaction rate was performed from the experimental results of the breakthrough curve by using a fixed-bed reaction model, and the reaction rate constants and adsorption capacity were obtained for achieving an optimal process design.

  10. Thermal solid-state Z/E isomerization of 2-alkylidene-4-oxothiazolidines: effects of non-covalent interactions

    Directory of Open Access Journals (Sweden)

    ZDRAVKO DŽAMBASKI

    2011-03-01

    Full Text Available Configurational isomerization of stereo-defined 5-substituted and unsubstituted 2-alkylidene-4-oxothiazolidines (1 in the solid state, giving the Z/E mixtures in various ratios, was investigated by 1H-NMR spectroscopy, X-ray powder crystallography and differential scanning calorimetry (DSC. The Z/E composition can be rationalized in terms of non-covalent interactions, involving intermolecular and intramolecular hydrogen bonding and directional non-bonded 1,5-type S×××O interactions. X-Ray powder crystallography, using selected crystalline (Z-4-oxothiazolidine substrates, revealed transformation to the amorphous state during the irreversible Z®E process. A correlation between previous results on the Z/E isomerization in solution and now in the solid state was established.

  11. Solution and solid-state electrochemiluminescence of a fac-tris(2-phenylpyridyl)iridium(III)-cored dendrimer

    International Nuclear Information System (INIS)

    Reid, Ellen F.; Burn, Paul L.; Lo, Shih-Chun; Hogan, Conor F.

    2013-01-01

    The solution phase and solid-state electrochemistry and electrochemiluminescence (ECL) of an iridium(III) complex-cored dendrimeric analogue of Ir(ppy) 3 , (G1pIr), are reported. The solid-state electrochemistry and solid-state ECL of Ir(ppy) 3 itself is also described for the first time. In solution phase, the dendrimer displays greater immunity to oxygen quenching in photoluminescence (PL) experiments and exhibits greater ECL efficiency compared to the parent Ir(ppy) 3 core under the same conditions, despite a lower photoluminescence quantum yield. It is proposed that the dendrons which effectively shield the core from PL quenching interactions in the solid-state counteract the effects of parasitic side-reactions during the solution ECL experiments. Electroactive and ECL-active solid-state films of both Ir(ppy) 3 and G1pIr were produced by drop-coating on boron doped diamond electrodes. Films of Ir(ppy) 3 produced stable co-reactant ECL. However, films of G1pIr produced lower than expected ECL intensity. This was attributed to poorer charge transport and the lipophilicity of the film limiting the rate of interaction with the co-reactant required for formation of the excited state

  12. Solid-State NMR Study of New Copolymers as Solid Polymer Electrolytes

    Directory of Open Access Journals (Sweden)

    Jean-Christophe Daigle

    2018-01-01

    Full Text Available We report the analysis of comb-like polymers by solid-state NMR. The polymers were previously evaluated as solid-polymer-electrolytes (SPE for lithium-polymer-metal batteries that have suitable ionic conductivity at 60 °C. We propose to develop a correlation between 13C solid-state NMR measurements and phase segregation. 13C solid-state NMR is a perfect tool for differentiating polymer phases with fast or slow motions. 7Li was used to monitor the motion of lithium ions in the polymer, and activation energies were calculated.

  13. Effects of solid fission products forming dissolved oxide (Nd) and metallic precipitate (Ru) on the thermal conductivity of uranium base oxide fuel

    International Nuclear Information System (INIS)

    Kim, Dong-Joo; Yang, Jae-Ho; Kim, Jong-Hun; Rhee, Young-Woo; Kang, Ki-Won; Kim, Keon-Sik; Song, Kun-Woo

    2007-01-01

    The effects of solid fission products on the thermal conductivity of uranium base oxide nuclear fuel were experimentally investigated. Neodymium (Nd) and ruthenium (Ru) were added to represent the physical states of solid fission products such as 'dissolved oxide' and 'metallic precipitate', respectively. Thermal conductivity was determined on the basis of the thermal diffusivity, density and specific heat values. The effects of the additives on the thermal conductivity were quantified in the form of the thermal resistivity equation - the reciprocal of the phonon conduction equation - which was determined from the measured data. It is concluded that the thermal conductivity of the irradiated nuclear fuel is affected by both the 'dissolved oxide' and the 'metallic precipitate', however, the effects are in the opposite direction and the 'dissolved oxide' influences the thermal conductivity more significantly than that of the 'metallic precipitate'

  14. Partitioned airs at microscale and nanoscale: thermal diffusivity in ultrahigh porosity solids of nanocellulose

    Science.gov (United States)

    Sakai, Koh; Kobayashi, Yuri; Saito, Tsuguyuki; Isogai, Akira

    2016-02-01

    High porosity solids, such as plastic foams and aerogels, are thermally insulating. Their insulation performance strongly depends on their pore structure, which dictates the heat transfer process in the material. Understanding such a relationship is essential to realizing highly efficient thermal insulators. Herein, we compare the heat transfer properties of foams and aerogels that have very high porosities (97.3-99.7%) and an identical composition (nanocellulose). The foams feature rather closed, microscale pores formed with a thin film-like solid phase, whereas the aerogels feature nanoscale open pores formed with a nanofibrous network-like solid skeleton. Unlike the aerogel samples, the thermal diffusivity of the foam decreases considerably with a slight increase in the solid fraction. The results indicate that for suppressing the thermal diffusion of air within high porosity solids, creating microscale spaces with distinct partitions is more effective than directly blocking the free path of air molecules at the nanoscale.

  15. High Reversibility of “Soft” Electrode Materials in All-Solid-State Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Sakuda, Atsushi, E-mail: a.sakuda@aist.go.jp; Takeuchi, Tomonari, E-mail: a.sakuda@aist.go.jp; Shikano, Masahiro; Sakaebe, Hikari; Kobayashi, Hironori [Department of Energy and Environment, Research Institute for Electrochemical Energy, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda (Japan)

    2016-05-10

    All-solid-state batteries using inorganic solid electrolytes (SEs) are considered to be ideal batteries for electric vehicles and plug-in hybrid electric vehicles because they are potentially safer than conventional lithium-ion batteries (LIBs). In addition, all-solid-state batteries are expected to have long battery life owing to the inhibition of chemical side reactions because only lithium ions move through the typically used inorganic SEs. The development of high-energy density (more than 300 Wh kg{sup −1}) secondary batteries has been eagerly anticipated for years. The application of high-capacity electrode active materials is essential for fabricating such batteries. Recently, we proposed metal polysulfides as new electrode materials. These materials show higher conductivity and density than sulfur, which is advantageous for fabricating batteries with relatively higher energy density. Lithium niobium sulfides, such as Li{sub 3}NbS{sub 4}, have relatively high density, conductivity, and rate capability among metal polysulfide materials, and batteries with these materials have capacities high enough to potentially exceed the gravimetric-energy density of conventional LIBs. Favorable solid–solid contact between the electrode and electrolyte particles is a key factor for fabricating high performance all-solid-state batteries. Conventional oxide-based positive electrode materials tend to give rise to cracks during fabrication and/or charge–discharge processes. Here, we report all-solid-state cells using lithium niobium sulfide as a positive electrode material, where favorable solid–solid contact was established by using lithium sulfide electrode materials because of their high processability. Cracks were barely observed in the electrode particles in the all-solid-state cells before or after charging and discharging with a high capacity of approximately 400 mAh g{sup −1} suggesting that the lithium niobium sulfide electrode charged and discharged without

  16. High Reversibility of “Soft” Electrode Materials in All-Solid-State Batteries

    International Nuclear Information System (INIS)

    Sakuda, Atsushi; Takeuchi, Tomonari; Shikano, Masahiro; Sakaebe, Hikari; Kobayashi, Hironori

    2016-01-01

    All-solid-state batteries using inorganic solid electrolytes (SEs) are considered to be ideal batteries for electric vehicles and plug-in hybrid electric vehicles because they are potentially safer than conventional lithium-ion batteries (LIBs). In addition, all-solid-state batteries are expected to have long battery life owing to the inhibition of chemical side reactions because only lithium ions move through the typically used inorganic SEs. The development of high-energy density (more than 300 Wh kg −1 ) secondary batteries has been eagerly anticipated for years. The application of high-capacity electrode active materials is essential for fabricating such batteries. Recently, we proposed metal polysulfides as new electrode materials. These materials show higher conductivity and density than sulfur, which is advantageous for fabricating batteries with relatively higher energy density. Lithium niobium sulfides, such as Li 3 NbS 4 , have relatively high density, conductivity, and rate capability among metal polysulfide materials, and batteries with these materials have capacities high enough to potentially exceed the gravimetric-energy density of conventional LIBs. Favorable solid–solid contact between the electrode and electrolyte particles is a key factor for fabricating high performance all-solid-state batteries. Conventional oxide-based positive electrode materials tend to give rise to cracks during fabrication and/or charge–discharge processes. Here, we report all-solid-state cells using lithium niobium sulfide as a positive electrode material, where favorable solid–solid contact was established by using lithium sulfide electrode materials because of their high processability. Cracks were barely observed in the electrode particles in the all-solid-state cells before or after charging and discharging with a high capacity of approximately 400 mAh g −1 suggesting that the lithium niobium sulfide electrode charged and discharged without experiencing

  17. Solid Lithium Ion Conductors (SLIC) for Lithium Solid State Batteries

    Data.gov (United States)

    National Aeronautics and Space Administration — To identify the most lithium-ion conducting solid electrolytes for lithium solid state batteries from the emerging types of solid electrolytes, based on a...

  18. Polycarbonate-based polyurethane as a polymer electrolyte matrix for all-solid-state lithium batteries

    Science.gov (United States)

    Bao, Junjie; Shi, Gaojian; Tao, Can; Wang, Chao; Zhu, Chen; Cheng, Liang; Qian, Gang; Chen, Chunhua

    2018-06-01

    Four kinds of polycarbonate-based polyurethane with 8-14 wt% hard segments content are synthesized via reactions of polycarbonatediol, hexamethylene diisocyanate and diethylene glycol. The mechanical strength of the polyurethanes increase with the increase of hard segments content. Solid polymer electrolytes composed of the polycarbonate-based polyurethanes and LiTFSI exhibits fascinating characteristics for all-solid-state lithium batteries with a high ionic conductivity of 1.12 × 10-4 S cm-1 at 80 °C, an electrochemical stability window up to 4.5 V (vs. Li+/Li), excellent mechanical strength and superior interfacial stability against lithium metal. The all-solid-state batteries using LiFePO4 cathode can deliver high discharge capacities (161, 158, 134 and 93 mAh g-1 at varied rates of 0.2, 0.5, 1 and 2 C) at 80 °C and excellent cycling performance (with 91% capacity retention after 600 cycles at 1 C). All the results indicate that such a polyurethane-based solid polymer electrolyte can be a promising candidate for all-solid-state lithium batteries.

  19. Mechanistic Aspects of the Thermal Decomposition of Dicyclopentadienyltitanium(IV)diaryl Compounds

    NARCIS (Netherlands)

    Boekel, C.P.; Teuben, J.H.; Liefde Meijer, H.J. de

    1975-01-01

    The thermal decomposition of a number of compounds Cp2TiR2 (R = aryl) was studied in the solid state and in various solvents. A first-order reaction was observed and activation energies of 20-30 kcal mol-1 were found depending on the nature of R. The activation energy for Cp2Ti(C6H5)2 (20-22 kcal

  20. Through-furnace for burning solid organic substances

    International Nuclear Information System (INIS)

    Kemmler, G.; Schlich, E.

    1984-01-01

    The through-furnace for burning radio-active organic solid waste consists of a reaction pipe heated from the outside, an input device and an output device. A solid pump is used as the input device, which has a common longitudinal axis with the reaction pipe. The reaction pipe is widened in the transport direction of the combustion pipe, where the angle between the longitudinal axis and the pipe wall is 0.5 to 5 0 . The pipe wall is wholely or partially permeable to gas. The thermal treatment of the solid organic substances can occur by combustion or by pyrohydrolysis or pyrolysis in the through-furnace. (orig./HP) [de

  1. Solid state magnetism

    CERN Document Server

    Crangle, John

    1991-01-01

    Solid state magnetism is important and attempts to understand magnetic properties have led to an increasingly deep insight into the fundamental make up of solids. Both experimental and theoretical research into magnetism continue to be very active, yet there is still much ground to cover before there can be a full understanding. There is a strong interplay between the developments of materials science and of magnetism. Hundreds of new materials have been dis­ covered, often with previously unobserved and puzzling magnetic prop­ erties. A large and growing technology exists that is based on the magnetic properties of materials. Very many devices used in everyday life involve magnetism and new applications are being invented all the time. Under­ standing the fundamental background to the applications is vital to using and developing them. The aim of this book is to provide a simple, up-to-date introduction to the study of solid state magnetism, both intrinsic and technical. It is designed to meet the needs a...

  2. Solid state photochemistry. Subpanel A-2(c): Challenges and opportunities in photochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Czanderna, A.W. [National Renewable Energy Laboratory, Golden, CO (United States)

    1996-09-01

    In contrast with the prior two subsections, the topics in solid state photochemistry range from photo(thermal)-induced degradation to synthesizing new compounds with desirable functions or properties. We will therefore discuss the importance of each relative to existing technological barriers, recent progress, potential applications, and the advantages expected from new information from basic science, especially, as it relates to the DOE mission.

  3. Physico-chemical studies on samarium soaps in solid state

    International Nuclear Information System (INIS)

    Mehrotra, K.N.; Chauhan, M.; Shukla, R.K.

    1989-01-01

    The physico-chemical characteristics of samarium soaps (caproate and caprate) in solid state were investigated by IR, X-ray diffraction and TGA measurements. The IR results revealed that the fatty acids exist in dimeric state through hydrogen bonding and samarium soaps possess partial ionic character. The X-ray diffraction measurements were used to calculate the long spacings and the results confirmed the double layer structure of samarium soaps. The decomposition reaction was found kinetically of zero order and the values of energy of activation for the decomposition process for caproate and caprate were found to be 8,0 and 7,8 kcal mol -1 , respectively. (Authors)

  4. ELECTRICAL RESISTIVITY AND SEEBECK COEFFICIENT IN Ca(LaMnO COMPOUNDS PREPARED BY SOLID STATE REACTION METHOD

    Directory of Open Access Journals (Sweden)

    Jorge I. Villa

    2017-01-01

    Full Text Available By using the solid state reaction method samples of  Ca1-xLaxMnO3 (0 ≤ x ≥ 0.15 were prepared. Their transport properties were studied by electrical resistivity rho(T and Seebeck coefficient S(T measurements as a function of temperature and lanthanum content, in the temperature range between 100 and 290K. The structural and morphological properties were studied by X-ray diffraction analysis (XRD and scanning electron microscopy (SEM, respectively. The Seebeck coefficient is negative throughout the studied temperature range indicating a conduction given by negative charge carriers, its magnitude decreases with the lanthanum content from |-261| mV/K to |-120| mV/K. The electrical resistivity shows a semiconducting behavior, it was interpreted in terms of small polaron hopping model. Thermoelectric properties of the obtained compounds were studied by the thermoelectric power factor PF, which reaches maximum values around 2mW/K2cm, these values become this kind of ceramics promising thermoelectric compound, to be used in technological applications.

  5. Room temperature photoluminescence in the visible range from silicon nanowires grown by a solid-state reaction

    International Nuclear Information System (INIS)

    Anguita, J V; Sharma, P; Henley, S J; Silva, S R P

    2009-01-01

    The solid-liquid-solid method (also known as the solid-state method) is used to produce silicon nanowires at the core of silica nanowires with a support catalyst layer structure of nickel and titanium layers sputtered on oxide-coated silicon wafers. This silane-free process is low cost and large-area compatible. Using electron microscopy and Raman spectroscopy we deduce that the wires have crystalline silicon cores. The nanowires show photoluminescence in the visible range (orange), and we investigate the origin of this band. We further show that the nanowires form a random mesh that acts as an efficient optical trap, giving rise to an optically absorbing medium.

  6. Room temperature photoluminescence in the visible range from silicon nanowires grown by a solid-state reaction

    Science.gov (United States)

    Anguita, J. V.; Sharma, P.; Henley, S. J.; Silva, S. R. P.

    2009-11-01

    The solid-liquid-solid method (also known as the solid-state method) is used to produce silicon nanowires at the core of silica nanowires with a support catalyst layer structure of nickel and titanium layers sputtered on oxide-coated silicon wafers. This silane-free process is low cost and large-area compatible. Using electron microscopy and Raman spectroscopy we deduce that the wires have crystalline silicon cores. The nanowires show photoluminescence in the visible range (orange), and we investigate the origin of this band. We further show that the nanowires form a random mesh that acts as an efficient optical trap, giving rise to an optically absorbing medium.

  7. Method and apparatus for obtaining enhanced production rate of thermal chemical reactions

    Science.gov (United States)

    Tonkovich, Anna Lee Y [Pasco, WA; Wang, Yong [Richland, WA; Wegeng, Robert S [Richland, WA; Gao, Yufei [Kennewick, WA

    2003-04-01

    The present invention is a method and apparatus (vessel) for providing a heat transfer rate from a reaction chamber through a wall to a heat transfer chamber substantially matching a local heat transfer rate of a catalytic thermal chemical reaction. The key to the invention is a thermal distance defined on a cross sectional plane through the vessel inclusive of a heat transfer chamber, reaction chamber and a wall between the chambers. The cross sectional plane is perpendicular to a bulk flow direction of the reactant stream, and the thermal distance is a distance between a coolest position and a hottest position on the cross sectional plane. The thermal distance is of a length wherein the heat transfer rate from the reaction chamber to the heat transfer chamber substantially matches the local heat transfer rate.

  8. Thermal Reactions of H2O2 on Icy Satellites and Small Bodies: Descent with Modification?

    Science.gov (United States)

    Hudson, Reggie L.; Loeffler, Mark J.

    2012-01-01

    Magnetospheric radiation drives surface and near-surface chemistry on Europa, but below a few meters Europa's chemistry is hidden from direct observation . As an example, surface radiation chemistry converts H2O and SO2 into H2O2 and (SO4)(sup 2-), respectively, and these species will be transported downward for possible thermally-driven reactions. However, while the infrared spectra and radiation chemistry of H2O2-containing ices are well documented, this molecule's thermally-induced solid-phase chemistry has seldom been studied. Here we report new results on thermal reactions in H2O + H2O2 + SO2 ices at 50 - 130 K. As an example of our results, we find that warming H2O + H2O2 + SO2 ices promotes SO2 oxidation to (SO4)(sup 2-). These results have implications for the survival of H2O2 as it descends, with modification, towards a subsurface ocean on Europa. We suspect that such redox chemistry may explain some of the observations related to the presence and distribution of H2O2 across Europa's surface as well as the lack of H2O2 on Ganymede and Callisto.

  9. thermal analysis of a small scale solid waste-fired steam boiler

    African Journals Online (AJOL)

    user

    Thermal analysis of a small scale solid waste-fired steam generator is presented in this paper. The analysis was based on the chosen design specifications which are operating steam ... include: wind, bio-energy, geothermal, solar thermal,.

  10. Reaction Hamiltonian and state-to-state description of chemical reactions

    International Nuclear Information System (INIS)

    Ruf, B.A.; Kresin, V.Z.; Lester, W.A. Jr.

    1985-08-01

    A chemical reaction is treated as a quantum transition from reactants to products. A specific reaction Hamiltonian (in second quantization formalism) is introduced. The approach leads to Franck-Condon-like factor, and adiabatic method in the framework of the nuclear motion problems. The influence of reagent vibrational state on the product energy distribution has been studied following the reaction Hamiltonian method. Two different cases (fixed available energy and fixed translational energy) are distinguished. Results for several biomolecular reactions are presented. 40 refs., 5 figs

  11. High-powered, solid-state rf systems

    International Nuclear Information System (INIS)

    Reid, D.W.

    1987-01-01

    Over the past two years, the requirement to supply megawatts of rf power for space-based applications at uhf and L-band frequencies has caused dramatic increases in silicon solid-state power capabilities in the frequency range from 10 to 3000 MHz. Radar and communications requirements have caused similar increases in gallium arsenide solid-state power capabilities in the frequency ranges from 3000 to 10,000 MHz. This paper reviews the present state of the art for solid-state rf amplifiers for frequencies from 10 to 10,000 MHz. Information regarding power levels, size, weight, and cost will be given. Technical specifications regarding phase and amplitude stability, efficiency, and system architecture will be discussed. Solid-stage rf amplifier susceptibility to radiation damage will also be examined

  12. Solid-state lithium battery

    Science.gov (United States)

    Ihlefeld, Jon; Clem, Paul G; Edney, Cynthia; Ingersoll, David; Nagasubramanian, Ganesan; Fenton, Kyle Ross

    2014-11-04

    The present invention is directed to a higher power, thin film lithium-ion electrolyte on a metallic substrate, enabling mass-produced solid-state lithium batteries. High-temperature thermodynamic equilibrium processing enables co-firing of oxides and base metals, providing a means to integrate the crystalline, lithium-stable, fast lithium-ion conductor lanthanum lithium tantalate (La.sub.1/3-xLi.sub.3xTaO.sub.3) directly with a thin metal foil current collector appropriate for a lithium-free solid-state battery.

  13. A new chemical route to a hybrid nanostructure: room-temperature solid-state reaction synthesis of Ag@AgCl with efficient photocatalysis.

    Science.gov (United States)

    Hu, Pengfei; Cao, Yali

    2012-08-07

    The room-temperature solid-state chemical reaction technique has been used to synthesize the silver nanoparticle-loaded semiconductor silver@silver chloride for the first time. It has the advantages of convenient operation, lower cost, less pollution, and mass production. This simple technique created a wide array of nanosized silver particles which had a strong surface plasmon resonance effect in the visible region, and built up an excellent composite structure of silver@silver chloride hybrid which exhibited high photocatalytic activity and stability towards decomposition of organic methyl orange under visible-light illumination. Moreover, this work achieved the control of composition of the silver@silver chloride composite simply by adjusting the feed ratio of reactants. It offers an alternative method for synthesising metal@semiconductor composites.

  14. Carbon doped lanthanum aluminate (LaAlO3:C) UV thermoluminescent properties synthesized by solid state reaction with three different mixing methodologies

    International Nuclear Information System (INIS)

    Alves, N.

    2017-01-01

    In this work we discuss the thermoluminescent (TL) response for LaAlO 3 :C crystals grown by using three different combinations of Al 2 O 3 , La 2 O 3 and carbon atoms during the synthesis process. Recently, LaAlO 3 single crystals, co-doped with Ce 3+ and Dy 3+ rare earth trivalent ions and grown under hydrothermal conditions, have been reported to show high thermoluminescent response (TL) when exposed to low levels of ultraviolet radiation (UVR). However, undoped LaAlO 3 synthesized by solid state reaction method from the 1:1 mixture of aluminum and lanthanum oxide under reducing atmosphere revealed to have still higher thermoluminescent sensitivity to UV photon fields than the co-doped with Ce 3+ and Dy 3+ . It is well known that carbon doped aluminum oxide monocrystals have excellent TL and photoluminescent response properties for X-rays, UV and gamma radiation fields. Thus, we conducted three different syntheses of LaAlO 3 by the solid state reaction method, doping the mixture with carbon. The lanthanum aluminate polycrystals were synthesized from the 1:1 mixture of aluminum and lanthanum oxide, adding 0.1wt.% carbon and annealed at 1700°C for two hours in hydrogen atmosphere. The X-ray diffraction analysis revealed the formation of rhombohedral LaAlO 3 crystallographic phase, however a small percentage (15%) of Al 2 O 3 has been also identified. The UV-Vis absorbance spectra were obtained and F and F + - center were ascribed. The UV irradiations were carried out using a commercial 8W UV lamp. Thermoluminescence measurements were performed at a Harshaw 4500 TL reader. All compositions investigated have shown high TL sensitivity to UVR. (author)

  15. Theoretical and experimental study on solid chemical reaction between BaCO3 and TiO2 in microwave field

    International Nuclear Information System (INIS)

    Liu Hanxing; Guo, Liling; Zou Long; Cao Minhe; Zhou Jian; Ouyang Shixi

    2004-01-01

    Solid-state chemical reaction mechanism for the reaction between BaCO 3 and TiO 2 in microwave field was investigated based on X-ray power diffraction (XRD) data and theory of diffusion. The compositions of the resultant after reaction under different conditions were studied by employing XRD. The quantitative analyses based on XRD data showed the reaction in microwave field was quite different from that in the conventional method. A model was proposed to explain the change of the ratio between the reactant BaCO 3 , TiO 2 and the resultant BaTiO 3 for the chemical reaction. The formation kinetic of BaTiO 3 from the BaCO 3 and TiO 2 was calculated by employing this theoretical model. The reaction rate between BaCO 3 and TiO 2 in microwave field was much higher than that in conventional method. The activation energy of the atomic diffusions in this solid chemical reaction is only 58 kJ/mol, which was only about 1/4 of 232 kJ/mol in the conventional value. The result suggests that the microwave field enhance atomic diffusion during the reaction

  16. A Solid State Pyranometer

    Directory of Open Access Journals (Sweden)

    Dumitrescu Anca Laura

    2015-12-01

    Full Text Available The construction of a solid state device-based pyranometer designated to broadband irradiance measurements is presented in this paper. The device is built on the physical basis that the temperature difference between two bodies of identical shape and external surface area, identically exposed to the incident radiation, but having different absorption and heat transfer coefficients (e.g. one body is painted white and the other is painted black, is proportional to the incident irradiance. This proportionality may be put in evidence if the two bodies consisting of identical arrays of correspondingly painted semiconductor diodes, due to the thermal behaviour of their p-n junction. It is theoretically predicted and experimentally confirmed that the voltage drop across a diode passed through a constant forward current linearly decreases with the temperature of the junction. In other words, a signal proportional to the irradiance of the light source may be obtained via conventional analog electronics. The calibration of the apparatus, as performed by means of a professional device (LP PYRA 03, indicates a good linearity.

  17. A Solid State Pyranometer

    Science.gov (United States)

    Dumitrescu, Anca Laura; Paulescu, Marius; Ercuta, Aurel

    2015-12-01

    The construction of a solid state device-based pyranometer designated to broadband irradiance measurements is presented in this paper. The device is built on the physical basis that the temperature difference between two bodies of identical shape and external surface area, identically exposed to the incident radiation, but having different absorption and heat transfer coefficients (e.g. one body is painted white and the other is painted black), is proportional to the incident irradiance. This proportionality may be put in evidence if the two bodies consisting of identical arrays of correspondingly painted semiconductor diodes, due to the thermal behaviour of their p-n junction. It is theoretically predicted and experimentally confirmed that the voltage drop across a diode passed through a constant forward current linearly decreases with the temperature of the junction. In other words, a signal proportional to the irradiance of the light source may be obtained via conventional analog electronics. The calibration of the apparatus, as performed by means of a professional device (LP PYRA 03), indicates a good linearity.

  18. Influence of foaming agents on solid thermal conductivity of foam glasses prepared from CRT panel glass

    DEFF Research Database (Denmark)

    Østergaard, Martin Bonderup; Petersen, Rasmus Rosenlund; König, Jakob

    2017-01-01

    The understanding of the thermal transport mechanism of foam glass is still lacking. The contribution of solid- and gas conduction to the total thermal conductivity remains to be reported. In many foam glasses, the solid phase consist of a mix of an amorphous and a crystalline part where foaming...... containing glass and crystalline foaming agents and amorphous samples where the foaming agents are completely dissolved in the glass structure, respectively. Results show that the samples prepared by sintering have a higher thermal conductivity than the samples prepared by melt-quenching. The thermal...... conductivities of the sintered and the melt-quenched samples represent an upper and lower limit of the solid phase thermal conductivity of foam glasses prepared with these foaming agents. The content of foaming agents dissolved in the glass structure has a major impact on the solid thermal conductivity of foam...

  19. Solid-phase vibrational redox reactions in coordinated oxides

    International Nuclear Information System (INIS)

    Kostikova, G.P.; Korol'kov, D.V.; Kostikov, Yu.P.

    1996-01-01

    The properties of multicomponent oxides (YBa 2 Cu 3 O 7-x , etc.), incorporating different valency forms of each of two (or more) different elements have been compared with the properties of the known chemical systems, where vibrational (periodic) redox-reactions are realized a fortiori. The essence of the new theoretical concept suggested consists in the following: high-T c superconductivity of the complex oxides and similar compounds originates from vibrational redox reaction proceeding in solid phase and involving different valency atoms of every element

  20. High peak power picosecond hybrid fiber and solid-state amplifier system

    International Nuclear Information System (INIS)

    Wushouer, X; Yan, P; Yu, H; Liu, Q; Fu, X; Yan, X; Gong, M

    2010-01-01

    We report the high peak power picosecond hybrid fiber and solid-state laser amplifier system. The passively mode-locked solid-state seed source produced an average power of 1.8 W with pulse width of 14 ps and repetition rate of 86 MHz. It was directly coupled into the first Yb-doped polarized photonic crystal fiber amplifier stage. To avoid the nonlinear effects in fiber, the output power from the first stage was merely amplified to 24 W with the narrow spectra broadening of 0.21 nm. For the improvement of the peak power, the dual-end pumped composite Nd:YVO 4 amplifier system has been chosen at the second stage. To reduce the serious thermal effect, the thermally bonded composite YVO 4 – Nd:YVO 4 – YVO 4 rod crystal was used as the gain medium. The 53 W TEM 00 mode with the peak power of 40 kW, beam quality of M 2 < 1.15, corresponding to the optical-optical efficiency of 42.4% was obtained at the hybrid amplifier laser system. The system allows using a low power seed source and demonstrates an increase in the peak power beyond a fiber master oscillator power amplifier's (MOPA's) limit

  1. Reaction mechanism and thermal stability study on cathode materials for rechargeable lithium ion batteries

    Science.gov (United States)

    Fang, Jin

    (0≤y≤0.4) is stable up to 600 °C with particle size above 100 nm particle. And in this work Mn rich olivine phase Fe1-yMnyPO4 is found to be thermally stable up to at least 450 °C with particle size down to below 50 nm, different delithiation methods result in different decomposition routes, electrochemical delithiation results in decreased thermal stability. Moisture exposure appears the most detrimental to the thermal stability of Mn-rich samples. LiNi0.5Mn1.5O4 has attracted a lot of attentions because the potential is even higher (˜ 4.7 V vs Li +/Li0). However, electrolyte decomposition is quite often observed during electrochemistry cycles due to the high voltage operation window. Spinel LiNi0.5Mn1.5O4 is known as ordered and disordered according to the distribution of cations which relates to the synthesis conditions. Mn and Ni ions distribute either randomly in 16d sites of an Fd3m-space group or ordered in 4a and 12d sites of P4332 space group. During discharge and charge processes, Li ions insert and extract from the structure with the oxidation state of Ni changing between +2 and +4 while Mn remains as Mn4+. So far the correlation between cation distribution and electrochemical performance is still unclear, mostly the disordered samples are observed to have better rate capabilities. In order to study the reaction mechanism, combined XRD and XAS are used to investigate the oxidation state of transition metals and structure change of LiNi0.5Mn1.5O4 during electrochemical cycling, disordered and ordered samples were compared and studied, and both samples show three phases transformation during charge and discharge. However, the samples suffer from severe electrolyte decomposition which has influence on the results. Good spinel samples with nice electrochemistry performance is required, pure spinel samples are obtained by using co-precipitation method, the distribution of transition metal ions can be controlled by controlling the synthesis temperature

  2. Thermal reactions of uranium metal, UO 2, U 3O 8, UF 4, and UO 2F 2 with NF 3 to produce UF 6

    Science.gov (United States)

    McNamara, Bruce; Scheele, Randall; Kozelisky, Anne; Edwards, Matthew

    2009-11-01

    This paper demonstrates that NF 3 fluorinates uranium metal, UO 2, UF 4, UO 3, U 3O 8, and UO 2F 2·2H 2O to produce the volatile UF 6 at temperatures between 100 and 550 °C. Thermogravimetric and differential thermal analysis reaction profiles are described that reflect changes in the uranium fluorination/oxidation state, physiochemical effects, and instances of discrete chemical speciation. Large differences in the onset temperatures for each system investigated implicate changes in mode of the NF 3 gas-solid surface interaction. These studies also demonstrate that NF 3 is a potential replacement fluorinating agent in the existing nuclear fuel cycle and in actinide volatility reprocessing.

  3. Fluidized Bed Reactor as Solid State Fermenter

    Directory of Open Access Journals (Sweden)

    Krishnaiah, K.

    2005-01-01

    Full Text Available Various reactors such as tray, packed bed, rotating drum can be used for solid-state fermentation. In this paper the possibility of fluidized bed reactor as solid-state fermenter is considered. The design parameters, which affect the performances are identified and discussed. This information, in general can be used in the design and the development of an efficient fluidized bed solid-state fermenter. However, the objective here is to develop fluidized bed solid-state fermenter for palm kernel cake conversion into enriched animal and poultry feed.

  4. An optics-based variable-temperature assay system for characterizing thermodynamics of biomolecular reactions on solid support

    Energy Technology Data Exchange (ETDEWEB)

    Fei, Yiyan; Landry, James P.; Zhu, X. D., E-mail: xdzhu@physics.ucdavis.edu [Department of Physics, University of California, One Shields Avenue, Davis, California 95616 (United States); Li, Yanhong; Yu, Hai; Lau, Kam; Huang, Shengshu; Chokhawala, Harshal A.; Chen, Xi [Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616 (United States)

    2013-11-15

    A biological state is equilibrium of multiple concurrent biomolecular reactions. The relative importance of these reactions depends on physiological temperature typically between 10 °C and 50 °C. Experimentally the temperature dependence of binding reaction constants reveals thermodynamics and thus details of these biomolecular processes. We developed a variable-temperature opto-fluidic system for real-time measurement of multiple (400–10 000) biomolecular binding reactions on solid supports from 10 °C to 60 °C within ±0.1 °C. We illustrate the performance of this system with investigation of binding reactions of plant lectins (carbohydrate-binding proteins) with 24 synthetic glycans (i.e., carbohydrates). We found that the lectin-glycan reactions in general can be enthalpy-driven, entropy-driven, or both, and water molecules play critical roles in the thermodynamics of these reactions.

  5. Electron stimulated reactions of methyl iodide coadsorbed with amorphous solid water

    International Nuclear Information System (INIS)

    Perry, C. C.; Faradzhev, N. S.; Madey, T. E.; Fairbrother, D. H.

    2007-01-01

    The electron stimulated reactions of methyl iodide (MeI) adsorbed on and suspended within amorphous solid water (ice) were studied using a combination of postirradiation temperature programmed desorption and reflection absorption infrared spectroscopy. For MeI adsorbed on top of amorphous solid water (ice), electron beam irradiation is responsible for both structural and chemical transformations within the overlayer. Electron stimulated reactions of MeI result principally in the formation of methyl radicals and solvated iodide anions. The cross section for electron stimulated decomposition of MeI is comparable to the gas phase value and is only weakly dependent upon the local environment. For both adsorbed MeI and suspended MeI, reactions of methyl radicals within MeI clusters lead to the formation of ethane, ethyl iodide, and diiodomethane. In contrast, reactions between the products of methyl iodide and water dissociation are responsible for the formation of methanol and carbon dioxide. Methane, formed as a result of reactions between methyl radicals and either parent MeI molecules or hydrogen atoms, is also observed. The product distribution is found to depend on the film's initial chemical composition as well as the electron fluence. Results from this study highlight the similarities in the carbon-containing products formed when monohalomethanes coadsorbed with amorphous solid water are irradiated by either electrons or photons

  6. Solid state physics for metallurgists

    CERN Document Server

    Weiss, Richard J

    2013-01-01

    Metal Physics and Physical Metallurgy, Volume 6: Solid State Physics for Metallurgists provides an introduction to the basic understanding of the properties that make materials useful to mankind. This book discusses the electronic structure of matter, which is the domain of solid state physics.Organized into 12 chapters, this volume begins with an overview of the electronic structure of free atoms and the electronic structure of solids. This text then examines the basis of the Bloch theorem, which is the exact periodicity of the potential. Other chapters consider the fundamental assumption in

  7. Solid-State Powered X-band Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Othman, Mohamed A.K. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Nann, Emilio A. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Dolgashev, Valery A. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Tantawi, Sami [SLAC National Accelerator Lab., Menlo Park, CA (United States); Neilson, Jeff [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2017-03-06

    In this report we disseminate the hot test results of an X-band 100-W solid state amplifier chain for linear accelerator (linac) applications. Solid state power amplifiers have become increasingly attractive solutions for achieving high power in radar and maritime applications. Here the performance of solid state amplifiers when driving an RF cavity is investigated. Commercially available, matched and fully-packaged GaN on SiC HEMTs are utilized, comprising a wideband driver stage and two power stages. The amplifier chain has a high poweradded- efficiency and is able to supply up to ~1.2 MV/m field gradient at 9.2 GHz in a simple test cavity, with a peak power exceeding 100 W. These findings set forth the enabling technology for solid-state powered linacs.

  8. The quantitative monitoring of mechanochemical reaction between solid L-tartaric acid and sodium carbonate monohydrate by terahertz spectroscopy

    Science.gov (United States)

    Liu, Xiaohong; Liu, Guifeng; Zhao, Hongwei; Zhang, Zengyang; Wei, Yongbo; Liu, Min; Wen, Wen; Zhou, Xingtai

    2011-11-01

    The solid-state reaction of chiral tartaric acid and alkali carbonate was studied by terahertz time-domain spectroscopy (THz-TDS). The sodium tartrate dihydrate was synthesized with high efficiency by mechanical grinding in the solid-state without waste that is particularly sustainable and environmentally benign. Distinct THz absorptions were observed for reactants and products. It indicates that THz spectroscopy is sensitive to different materials and crystal structures. The characteristic THz absorption peak at 1.09 THz of L (+)-Tartaric acid was selected for quantitative analysis. The reaction kinetics could be expressed by the Second-order equation and the Jander equation, which is consistent with a three-dimensional diffusion mechanism. The combination of multi-techniques including synchrotron radiation X-ray powder diffraction (SRXRPD), Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM) was used to investigate the grinding process and presented supporting evidences. The results demonstrate that THz spectroscopy technique has great potential applications in process monitoring and analysis in pharmaceutical and chemical synthesis industry.

  9. Solid state radiation chemistry. Features important in basic research and applications

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1998-01-01

    The basic research of chemical radiation effects has been mostly proceeded in aqueous systems. When one turns from aqueous to the 'dry solute' systems, reactions are running in a very different way. The examined compound, previously the solute, becomes then the only constituent of the system, absorbing all ionising energy. Majority of dosimeters and of radiation processed systems is solid: these are crystalline or rigid substances of high viscosity, sometimes of complicated phase-compositions being no longer homogenous like liquids. Main features of the solid (and rigid) state radiation chemistry is to be discussed in five parts: I. Character of absorption process. Absorption of radiation is in all media heterogenous on the molecular level, i.e. with formation of single- and multi-ionisation spurs. The yield of the latters is 15-25% of the total ionisations, depending on the system, even at low LET radiation. In spite of random distribution of initial ionisations, the single-ionisation spurs can turn rapidly into specifically arranged, temporal localisations. The variety of spur reactions is usually more complicated than that in aqueous systems. II. Character of transients. Intermediates in solid state radiation chemistry exhibit very different transport properties: from free electrons moving fast and far, to electrons changing the position by different physicochemical mechanisms, to easy movable H-atoms, and to practically unmovable, only vibrating, new fragments of a lattice or glass. III. Paramagnetic intermediates. Radicals living for microseconds in liquids, when created and trapped in a solid matrix are usually very stable, e.g. they can have a difference of half-life times of 12 orders of magnitude, however their chemical composition remais identical. (author)

  10. Low-temperature solid-state synthesis and optical properties of ZnO/CdS nanocomposites

    International Nuclear Information System (INIS)

    Liu, Jinsong; Zhu, Kongjun; Sheng, Beibei; Li, Ziquan; Tai, Guoan; Qiu, Jinhao; Wang, Jing; Chen, Jiankang; You, Yuncheng; Gu, Qilin; Liu, Pengcheng

    2015-01-01

    Highlights: • Using a low-temperature solid-state method, ZnO/CdS nanocomposites were obtained • Grain growth kinetics of cubic CdS and hexagonal ZnO phase was described. • Sufficient grinding and heating treatment was a key for formation of composites. • Optical properties could be easily manipulated by reaction temperature and time. - Abstract: A simple low-temperature solid-state reaction in the presence of the surfactant PEG400 was developed to obtain ZnO/CdS nanocomposites. The effects of synthesis temperature and reaction time on crystal structure and optical properties of the nanocomposites were investigated by several technologies. X-ray diffraction (XRD) and high resolution transmission electron microscope (HRTEM) characterizations showed that the products consisted of the nanoparticles, and the grain growth kinetics of the cubic CdS and the hexagonal ZnO phase in the nanocomposites was described. The mechanism analysis suggested that sufficient grinding and heating treatment was a key to form the ZnO/CdS nanocomposites, and the surfactant PEG400 was proved not to involve the reaction and prevent the nanoparticles from aggregating to larger in whole grinding and heat-treatment process. Ultraviolet–visible (UV–vis) spectra revealed that the band gaps of the nanocomposites could be tuned by the reaction temperature and reaction time. Photoluminescence (PL) spectra showed that the changing position and the intensity of the emission peaks resulted from the rate of electron transfer and recombination probability under the different conditions

  11. Thermophysical Properties of Matter - the TPRC Data Series. Volume 13. Thermal Expansion - Nonmetallic Solids

    Science.gov (United States)

    1977-01-01

    topography of the state of knowledge on the thermal expansion of nonmetallic solids. We believe there is also much food for reflec- West Lafayette...34 Lithium Silicates ......... 713 209 Magnesium Metasilicate MgSiO. .. ......... 715 210 Magnesium Orthosilicate Mg2 SiO . . . . . . . . . . . . 718 211...Antiferromagnetism of Praseodymium," Phys. Rev. Letters, 12(20), 553-5, 1964. 66. Goode, J.M., "Phase Transition Temperature of Polonium ,"J. Chem. Phys., 26(5), 1269

  12. Effects of calcination temperature on phase formation and particle size of Zn{sub 2}Nb{sub 34}O{sub 87} powder synthesized by solid-state reaction

    Energy Technology Data Exchange (ETDEWEB)

    Amonpattaratkit, Penphitcha, E-mail: p.amonpattaratkit@gmail.com [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Ananta, Supon, E-mail: suponananta@yahoo.com [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2013-05-15

    The solid-state mixed oxide method via a rapid vibro-milling technique was explored for the preparation of single-phase Zn{sub 2}Nb{sub 34}O{sub 87} nanopowders. Phase formation of zinc niobate was investigated as a function of calcination temperature by using a combination of thermogravimetric/differential thermal analyzer (TG/DTA) and X-ray diffraction (XRD) techniques. Morphology, particle size and chemical composition of the powders were determined by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) technique. The obtained results clearly revealed the influences of calcination temperature on phase formation and particle size of Zn{sub 2}Nb{sub 34}O{sub 87} nanopowder. - Highlights: ► Single phase Zn{sub 2}Nb{sub 34}O{sub 87} was firstly prepared by solid-state mixed oxide method via a rapid vibro-milling technique. ► The influences of calcination temperature on phase formation and particle size were investigated. ► Zn{sub 2}Nb{sub 34}O{sub 87} powders were characterized by TG–DTA, XRD, SEM and EDX.

  13. Solid-state reaction synthesis and aqueous durability of Ce-doped zirconolite-rich ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Guanjun [State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials, Southwest University of Science and Technology, Mianyang, Sichuan 621010 (China); Zhang, Kuibao, E-mail: xiaobao320@163.com [State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials, Southwest University of Science and Technology, Mianyang, Sichuan 621010 (China); Yin, Dan [State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials, Southwest University of Science and Technology, Mianyang, Sichuan 621010 (China); Zhang, Haibin, E-mail: hbzhang@imr.ac.cn [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900 (China)

    2015-11-15

    In this study, Ce-doped zirconolite-rich ceramics were prepared by solid-state reaction process using cerium as the surrogate of tetravalence actinide nuclide. The occupancy of Ce in the waste forms was investigated. The aqueous durability of Ce-doped zirconolite-rich ceramic was examined as well. The results show that zirconolite and pseudobrookite coexisted after being sintered at 1200 °C for 6 h. Meanwhile, perovskite is inevitable generated during the process. CeO{sub 2} can be successfully incorporated into the lattice structure of the zirconolite-rich ceramics. The maximum containing capacity of CeO{sub 2} is up to 14.95 wt% or y = 0.4. The normalized elemental leaching rates of Ce and Ca are fairly constant in low values of 1.2 × 10{sup −6} and 2.3 × 10{sup −2} g m{sup −2} d{sup −1} after 28 days. The normalized leaching rate of Fe is also in a low value of 2.9 × 10{sup −4} g m{sup −2} d{sup −1} after 7 days. - Highlights: • Ce-doped zirconolite-rich ceramic was produced at 1200 °C. • Pseudobrookite-type Fe{sub 2}TiO{sub 5} was employed to incorporate Fe element. • Ce{sup 3+} and Ce{sup 4+} coexisted in the Ce-doped zirconolite-rich waste form after being sintered at 1200 °C for 6 h. • The leaching rate of Ca was relatively higher than that of borosilicate glasses.

  14. Theoretical analysis for the specific heat and thermal parameters of solid C60

    Science.gov (United States)

    Soto, J. R.; Calles, A.; Castro, J. J.

    1997-08-01

    We present the results of a theoretical analysis for the thermal parameters and phonon contribution to the specific heat in solid C60. The phonon contribution to the specific heat is calculated through the solution of the corresponding dynamical matrix, for different points in the Brillouin zone, and the construccion of the partial and generalized phonon density of states. The force constants are obtained from a first principle calculation, using a SCF Hartree-Fock wave function from the Gaussian 92 program. The thermal parameters reported are the effective temperatures and vibrational amplitudes as a function of temperature. Using this model we present a parametization scheme in order to reproduce the general behaviour of the experimental specific heat for these materials.

  15. All-solid-state lithium batteries – The Mg2FeH6-electrode LiBH4-electrolyte system

    DEFF Research Database (Denmark)

    Huen, Priscilla; Ravnsbæk, Dorthe B.

    2018-01-01

    The complex hydride Mg2FeH6 is investigated as conversion type anode in a solid-state all-hydride Li-battery employing LiBH4 as solid-state electrolyte. In the solid-state battery, Mg2FeH6 exhibits improvements in the capacity retention and initial Coulombic efficiency of > 3 and > 2.5 times......, respectively, compared to the conventional liquid-electrolyte battery. Through investigations of the conversion reactions of Mg2FeH6, formation of MgH2 as intermediate in the conversion to Mg is discovered the first time. In addition, the effect of mixing procedure for the electrode-electrolyte composite...... on the battery performance is discussed....

  16. Computer simulation of the thermal pressure in solids and the equation of state

    International Nuclear Information System (INIS)

    Welch, D.O.; Dienes, G.J.; Paskin, A.

    1976-01-01

    The equation of state of solids was investigated with molecular dynamics techniques by obtaining the pressure as a function of temperature over a wide range of compressions. Data were obtained for fcc crystals with Lennard--Jones interactions and for bcc crystals with Morse interactions. The results were analyzed in terms of the Mie--Gruneisen equation of state. The Gruneisen constant at zero temperature is found to be essentially that obtained from the volume dependence of the mean-squared lattice vibration frequency, and its temperature dependence can be approximated well with a self-consistent cell model. Calculated results are compared with experimental data for argon along the melting line

  17. Microscale solid-state thermal diodes enabling ambient temperature thermal circuits for energy applications

    KAUST Repository

    Wang, Song; Cottrill, Anton L.; Kunai, Yuichiro; Toland, Aubrey R.; Liu, Pingwei; Wang, Wen-Jun; Strano, Michael S.

    2017-01-01

    rectifications range from 1.18 to 1.34. We show that such devices perform reliably enough to operate in thermal diode bridges, dynamic thermal circuits capable of transforming oscillating temperature inputs into single polarity temperature differences – analogous

  18. Method of operating a thermal engine powered by a chemical reaction

    Science.gov (United States)

    Ross, J.; Escher, C.

    1988-06-07

    The invention involves a novel method of increasing the efficiency of a thermal engine. Heat is generated by a non-linear chemical reaction of reactants, said heat being transferred to a thermal engine such as Rankine cycle power plant. The novel method includes externally perturbing one or more of the thermodynamic variables of said non-linear chemical reaction. 7 figs.

  19. Modern state of radiation chemistry of inorganic solids

    International Nuclear Information System (INIS)

    Zakharov, Yu.A.; Nevostruev, V.A.; Ryabykh, S.M.; Safonov, Yu.N.

    1985-01-01

    Regularities of radiolysis of different metal salts and inorganic acid complex anions are considered taking account of the nature of electron states and radiation transformations in them. By chemical processes during irradiation the solid salts considered are divided into 2 groups: salts in which the processes stimulated by radiation lead to chemical transformations in anion and cation subsystems, their valency changed, (1st group); salts in which radiation-chemical transformations influence anion sublattice and cation valency is without any change (2nd group). It is shown that the main part of secondary chemical transformations is realized from low-energy excited electron states. For first group salts these states are of cation nature, at this secondary reactions are determined by ionization processes. For second group salts low-energy electron terms are mostly of anion nature. Classification of inorganic salts by the character of transformations in anion sublattices is marked to be developed

  20. Annual Report of the Tandem Accelerator Center, Nuclear and Solid State Research Project, University of Tsukuba

    International Nuclear Information System (INIS)

    1978-01-01

    In 1977, 12 UD Pelletron tandem accelerator has been operated by the University's researchers and engineers. Except for the tank opening for regular inspection we met twice the troubles which forced to change the accelerating tube. The experiences teach us that it needs about 20 days to finish the conditioning after changing the accelerating tube. A sputter ion source of new version is now being installed on the top floor. Two devices for the detection of X-rays were tested. An apparatus for bombardment of samples in air for biological and medical sciences has been successfully used. The subjects of researches on nuclear physics cover the light-ion reactions, heavy-ion reactions and nuclear spectroscopy. A special emphasis has been put on the measurements on vector- and tensor-analyzing powers in the light-ion reactions, because of a higher efficiency of the polarized ion source. Elaborate works on the heavy-ion reactions including the angular correlation patterns and excitation functions have been made in parallel. Papers of these works are now being prepared, a few having been published already. Moreover, in the University of Tsukuba, a new research system, called Special Research Project on Nuclear and Solid State Sciences Using Accelerated Beams (Nuclear and Solid State Research Project) started in 1978 and will continue for five years. In this research project, researchers from various Institutes in the University of Tsukuba, as well as visiting researchers from other institutions in Japan and from abroad, participate. Using a variety of accelerated beams, i.e. of heavy, light and polarized beams, this research project aims mainly at the high excitation, short life, transient and inhomogeneous states both in nuclear and extra-nuclear world. It covers both fundamental research in nuclear, atomic and solid state sciences as well as their application in various fields. (J.P.N.)

  1. Measurement of Thermal Radiation Properties of Solids

    Science.gov (United States)

    Richmond, J. C. (Editor)

    1963-01-01

    The overall objectives of the Symposium were to afford (1) an opportunity for workers in the field to describe the equipment and procedures currently in use for measuring thermal radiation properties of solids, (2) an opportunity for constructive criticism of the material presented, and (3) an open forum for discussion of mutual problems. It was also the hope of the sponsors that the published proceedings of the Symposium would serve as a valuable reference on measurement techniques for evaluating thermal radiation properties of solids, partic.ularly for those with limited experience in the field. Because of the strong dependence of emitted flux upon temperature, the program committee thought it advisable to devote the first session to a discussion of the problems of temperature measurement. All of the papers in Session I were presented at the request of and upon topics suggested by the Committee. Because of time and space limitations, it, was impossible to consider all temperature measurement problems that might arise--the objective was rather to call to the attention of the reader some of the problems that might be encountered, and to provide references that might provide solutions.

  2. Magnetomechanical coupling in thermal amorphous solids

    Science.gov (United States)

    Hentschel, H. George E.; Ilyin, Valery; Mondal, Chandana; Procaccia, Itamar

    2018-05-01

    Standard approaches to magnetomechanical interactions in thermal magnetic crystalline solids involve Landau functionals in which the lattice anisotropy and the resulting magnetization easy axes are taken explicitly into account. In glassy systems one needs to develop a theory in which the amorphous structure precludes the existence of an easy axis, and in which the constituent particles are free to respond to their local amorphous surroundings and the resulting forces. We present a theory of all the mixed responses of an amorphous solid to mechanical strains and magnetic fields. Atomistic models are proposed in which we test the predictions of magnetostriction for both bulk and nanofilm amorphous samples in the paramagnetic phase. The application to nanofilms with emergent self-affine free interfaces requires a careful definition of the film "width" and its change due to the magnetostriction effect.

  3. Comparative studies on the production of cellulases by thermophilic fungi in submerged and solid-state fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Grajek, W

    1987-05-01

    Six thermophilic fungi were examined for their ability to produce cellulolytic enzymes in liquid (LF) and solid-state fermentation (SSF). The best cellulase activities were achieved by Thermoascus aurantiacus and Sporotrichum thermophile. Taking into consideration that solid-state medium obtained from 100 g of dry sugar-beet pulp occupies about 1 l of fermentor volume equivalent to 1 l of LF, it was confirmed that enzyme productivity per unit volume from both fungi was greater in SSF than in LF. The cellulase system obtained by SSF with T. aurantiacus contained 1.322 IU/l of exo-..beta..-D-glucanase, 53.269 IU/l of endo-..beta..-D-glucanase and 8.974 IU/l of ..beta..-D-glucosidase. The thermal and pH characteristics of cellulases from solid-state fermentation of T. aurantiacus and S. thermophile are described.

  4. Thermal Wigner Operator in Coherent Thermal State Representation and Its Application

    Institute of Scientific and Technical Information of China (English)

    FAN HongYi

    2002-01-01

    In the coherent thermal state representation we introduce thermal Wigner operator and find that it is"squeezed" under the thermal transformation. The thermal Wigner operator provides us with a new direct and neatapproach for deriving Wigner functions of thermal states.

  5. Solid-state lighting-a benevolent technology

    International Nuclear Information System (INIS)

    Schubert, E Fred; Kim, Jong Kyu; Luo Hong; Xi, J-Q

    2006-01-01

    Solid-state light sources are in the process of profoundly changing the way humans generate light for general lighting applications. Solid-state light sources possess two highly desirable features, which set them apart from most other light sources: (i) they have the potential to create light with essentially unit power efficiency and (ii) the properties of light, such as spectral composition and temporal modulation, can be controlled to a degree that is not possible with conventional light sources such as incandescent and fluorescent lamps. The implications are enormous and, as a consequence, many positive developments are to be expected including a reduction in global energy consumption, reduction of global-warming-gas and pollutant emissions and a multitude of new functionalities benefiting numerous applications. This review will assess the impact of solid-state lighting technology on energy consumption, the environment and on emerging application fields that make use of the controllability afforded by solid-state sources. The review will also discuss technical areas that fuel continued progress in solid-state lighting. Specifically, we will review the use of novel phosphor distributions in white light-emitting diodes (LEDs) and show the strong influence of phosphor distribution on efficiency. We will also review the use of reflectors in LEDs with emphasis on 'perfect' reflectors, i.e. reflectors with highly reflective omni-directional characteristics. Finally, we will discuss a new class of thin-film materials with an unprecedented low refractive index. Such low-n materials may strongly contribute to the continuous progress in solid-state lighting

  6. High speed real-time wavefront processing system for a solid-state laser system

    Science.gov (United States)

    Liu, Yuan; Yang, Ping; Chen, Shanqiu; Ma, Lifang; Xu, Bing

    2008-03-01

    A high speed real-time wavefront processing system for a solid-state laser beam cleanup system has been built. This system consists of a core2 Industrial PC (IPC) using Linux and real-time Linux (RT-Linux) operation system (OS), a PCI image grabber, a D/A card. More often than not, the phase aberrations of the output beam from solid-state lasers vary fast with intracavity thermal effects and environmental influence. To compensate the phase aberrations of solid-state lasers successfully, a high speed real-time wavefront processing system is presented. Compared to former systems, this system can improve the speed efficiently. In the new system, the acquisition of image data, the output of control voltage data and the implementation of reconstructor control algorithm are treated as real-time tasks in kernel-space, the display of wavefront information and man-machine conversation are treated as non real-time tasks in user-space. The parallel processing of real-time tasks in Symmetric Multi Processors (SMP) mode is the main strategy of improving the speed. In this paper, the performance and efficiency of this wavefront processing system are analyzed. The opened-loop experimental results show that the sampling frequency of this system is up to 3300Hz, and this system can well deal with phase aberrations from solid-state lasers.

  7. Study of organic ablative thermal-protection coating for solid rocket motor

    Science.gov (United States)

    Hua, Zenggong

    1992-06-01

    A study is conducted to find a new interior thermal-protection material that possesses good thermal-protection performance and simple manufacturing possibilities. Quartz powder and Cr2O3 are investigated using epoxy resin as a binder and Al2O3 as the burning inhibitor. Results indicate that the developed thermal-protection coating is suitable as ablative insulation material for solid rocket motors.

  8. Thermal Wigner Operator in Coherent Thermal State Representation and Its Application

    Institute of Scientific and Technical Information of China (English)

    FANHong-Yi

    2002-01-01

    In the coherent thermal state representation we introduce thermal Wigner operator and find that it is “squeezed” under the thermal transformation.The thermal Wigner operator provides us with a new direct and neat approach for deriving Wigner functions of thermal states.

  9. Two dimensional solid state NMR

    International Nuclear Information System (INIS)

    Kentgens, A.P.M.

    1987-01-01

    This thesis illustrates, by discussing some existing and newly developed 2D solid state experiments, that two-dimensional NMR of solids is a useful and important extension of NMR techniques. Chapter 1 gives an overview of spin interactions and averaging techniques important in solid state NMR. As 2D NMR is already an established technique in solutions, only the basics of two dimensional NMR are presented in chapter 2, with an emphasis on the aspects important for solid spectra. The following chapters discuss the theoretical background and applications of specific 2D solid state experiments. An application of 2D-J resolved NMR, analogous to J-resolved spectroscopy in solutions, to natural rubber is given in chapter 3. In chapter 4 the anisotropic chemical shift is mapped out against the heteronuclear dipolar interaction to obtain information about the orientation of the shielding tensor in poly-(oxymethylene). Chapter 5 concentrates on the study of super-slow molecular motions in polymers using a variant of the 2D exchange experiment developed by us. Finally chapter 6 discusses a new experiment, 2D nutation NMR, which makes it possible to study the quadrupole interaction of half-integer spins. 230 refs.; 48 figs.; 8 tabs

  10. Carbon doped lanthanum aluminate (LaAlO{sub 3}:C) UV thermoluminescent properties synthesized by solid state reaction with three different mixing methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Alves, N., E-mail: neire.radiologia@yahoo.com.br, E-mail: farialo@cdtn.br [Universidade Federal do Estado de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Ferraz, W.B.; Faria, L.O., E-mail: ferrazw@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    In this work we discuss the thermoluminescent (TL) response for LaAlO{sub 3}:C crystals grown by using three different combinations of Al{sub 2}O{sub 3}, La{sub 2}O{sub 3} and carbon atoms during the synthesis process. Recently, LaAlO{sub 3} single crystals, co-doped with Ce{sup 3+} and Dy{sup 3+} rare earth trivalent ions and grown under hydrothermal conditions, have been reported to show high thermoluminescent response (TL) when exposed to low levels of ultraviolet radiation (UVR). However, undoped LaAlO{sub 3} synthesized by solid state reaction method from the 1:1 mixture of aluminum and lanthanum oxide under reducing atmosphere revealed to have still higher thermoluminescent sensitivity to UV photon fields than the co-doped with Ce{sup 3+} and Dy{sup 3+}. It is well known that carbon doped aluminum oxide monocrystals have excellent TL and photoluminescent response properties for X-rays, UV and gamma radiation fields. Thus, we conducted three different syntheses of LaAlO{sub 3} by the solid state reaction method, doping the mixture with carbon. The lanthanum aluminate polycrystals were synthesized from the 1:1 mixture of aluminum and lanthanum oxide, adding 0.1wt.% carbon and annealed at 1700°C for two hours in hydrogen atmosphere. The X-ray diffraction analysis revealed the formation of rhombohedral LaAlO{sub 3} crystallographic phase, however a small percentage (15%) of Al{sub 2}O{sub 3} has been also identified. The UV-Vis absorbance spectra were obtained and F and F{sup +}- center were ascribed. The UV irradiations were carried out using a commercial 8W UV lamp. Thermoluminescence measurements were performed at a Harshaw 4500 TL reader. All compositions investigated have shown high TL sensitivity to UVR. (author)

  11. Effect of nanofiller’s size and shape on the solid state microstructure and thermal properties of poly(butylene succinate) nanocomposites

    International Nuclear Information System (INIS)

    Papageorgiou, Dimitrios G.; Chrissafis, Konstantinos; Pavlidou, Eleni; Deliyanni, Eleni A.; Papageorgiou, George Z.; Terzopoulou, Zoi; Bikiaris, Dimitrios N.

    2014-01-01

    Highlights: • The microstructure and thermal properties of PBSu-based nanocomposites were studied. • Ag and SiO 2 were dispersed more uniformly, compared to GO and MWCNTs. • PBSu/Ag nanocomposites exhibited higher nucleation activity and faster rates. • The order of nucleation efficiency of the fillers was GO < MWCNTs < SiO 2 < Ag. • The activation energy of nanocomposite samples was lower than that of PBSu. - Abstract: We report a study of the solid state microstructure and crystallization kinetics of poly(butylene succinate) (PBSu) reinforced with nanofillers of different shapes, sizes and geometries such as silver, silica (SiO 2 ), multi-walled carbon nanotubes (MWCNTs) and graphene oxide (GO). The solid state structure of neat polymer and nanocomposites were investigated by X-ray diffraction (XRD), polarized optical microscopy (POM) and transmission electron microscopy (TEM). The results indicated that the nanocomposite samples exhibited enhanced crystallinity and nucleation density, along with smaller spherulite size. Additionally, the spherical nanofillers were dispersed more uniformly in the polymeric matrix, than the other two filler types. The crystallization kinetics under both isothermal and dynamic conditions were also studied and as was expected, the nanocomposite samples, crystallize at higher rates due to the increased number of nucleation sites, as was calculated with Avrami, Dobreva and Friedman’s methods. From the crystallization study it was found that the nanocomposite filled with Ag nanoparticles exhibited the highest rates from all other fillers followed from SiO 2 and MWCNTs while GO showed the lowest rates

  12. Solid state microcavity dye lasers fabricated by nanoimprint lithography

    DEFF Research Database (Denmark)

    Nilsson, Daniel; Nielsen, Theodor; Kristensen, Anders

    2004-01-01

    propagating TE–TM modes. The laser cavity has the lateral shape of a trapezoid, supporting lasing modes by reflection on the vertical cavity walls. The solid polymer dye lasers emit laterally through one of the vertical cavity walls, when pumped optically through the top surface by means of a frequency...... doubled, pulsed Nd:YAG laser. Lasing in the wavelength region from 560 to 570 nm is observed from a laser with a side-length of 50 µm. In this proof of concept, the lasers are multimode with a mode wavelength separation of approximately 1.6 nm, as determined by the waveguide propagation constant......We present a solid state polymer microcavity dye laser, fabricated by thermal nanoimprint lithography (NIL) in a dye-doped thermoplast. The thermoplast poly-methylmethacrylate (PMMA) is used due to its high transparency in the visible range and its robustness to laser radiation. The laser dye...

  13. Unconventional exo selectivity in thermal normal-electron-demand Diels-Alder reactions

    Science.gov (United States)

    Ho, Guo-Ming; Huang, Ci-Jhang; Li, Elise Yu-Tzu; Hsu, Sheng-Kai; Wu, Ti; Zulueta, Medel Manuel L.; Wu, Kevin Binchia; Hung, Shang-Cheng

    2016-10-01

    The Diels-Alder reaction is a useful tool for generating functionalized chiral molecules through the concerted cycloaddition of dienes and dienophiles leading to six-membered rings. Traditionally, the selective predictions of the products rely heavily on consideration of the secondary orbital interactions that stabilize the endo pathway. However, there remain some basic examples defying this notion and produce the exo-isomer as major product. Here we systematically evaluated of the structural features driving exo selectivity in thermal normal-electron-demand Diels-Alder reactions. Substitution at the Cβ position and the size and electronegativity of the electron-withdrawing group of the dienophile are contributing factors. Experimental and computational studies both point toward the steric and electrostatic forces between the substituents in both the diene and the dienophile that increase the likelihood of the exo pathway. For these substrates, the dominance of the endo pathway is reduced by transition state distortions and poor structural alignments of the reacting partners. We also noted the tilt of the dienophile with respect to the diene causing steric strain on the functionalities at the more advanced bond forming carbon-carbon position of the endo transition state. Insights into such factors may benefit synthetic planning and asserting control over this important named reaction.

  14. Thermal Analysis of Fission Moly Target Solid Waste Storage

    Energy Technology Data Exchange (ETDEWEB)

    Son, Hyung Min; Park, Jonghark [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    There are various ways to produce Mo-99. Among them, nuclear transmutation of uranium target became the major one owing to its superior specific activity. After the fission molybdenum (FM) target is irradiated, it is transported to treatment facility to extract wanted isotope. During the process, various forms of wastes are produced including filter cake and other solid wastes. The filter cake is mostly consisted of decaying uranium compounds. The solid wastes are then packaged and moved to storage facility which will stay there for considerable amount of time. Being the continuous source of heat, the solid wastes are required to be cooled for the certain amount of time before transported to the storage area. In this study, temperature evaluation of the storage facility is carried out with pre-cooling time sensitivity to check its thermal integrity. In this study, thermal analysis on the FM target solid waste storage is performed. Finite volume method is utilized to numerically discretize and solve the geometry of interest. Analysis shows that the developed method can simulate temperature behavior during storage process, but needs to be checked against other code to see calculation accuracy. Highest temperature distribution is observed when every hole is filled with waste containers. Sensitivity results on pre-cooling time shows that at least 13 months of cooling is necessary to keep the structure integrity.

  15. In situ TEM observation of solid-gas reactions

    International Nuclear Information System (INIS)

    Kishita, K; Kamino, T; Watabe, A; Kuroda, K; Saka, H

    2008-01-01

    Under a gaseous atmosphere at high temperatures, almost all the materials (metal, catalysts, etc.) change their structures and properties. For the research and development of materials, it is of vital importance to clarify mechanisms of solid-gas and liquid-gas reactions. Recently an in situ TEM system combined with an environmental holder, which has a gas injection nozzle close to a specimen-heating element, has been developed. The gas injection nozzle permits gas to flow around the specimens sitting on the heating element made of a fine W filament. The newly developed in situ TEM has a differential pumping system; therefore, the pressure in the specimen chamber is maintained in the range of higher than 1 Pa, while the pressure in the electron gun chamber can be kept in the range of 10 -5 Pa. This system was applied to in situ observation of chemical reactions of metals with gases: Observation of oxidation and reduction under a gas pressure ranging from 10 -5 Pa to 1 Pa at high temperatures (room temperature to ∼1473 K) were successfully carried out on pure metal and rare metal catalysts at near-atomic resolution. This in situ environmental TEM system is promising for clarifying mechanisms of many solid-gas and liquid-gas reactions that take place at high temperatures under a gas atmosphere.

  16. Macroscopic modelling of solid-state fermentation

    NARCIS (Netherlands)

    Hoogschagen, M.J.

    2007-01-01

    Solid-state fermentation is different from the more well known process of liquid fermentation because no free flowing water is present. The technique is primarily used in Asia. Well-known products are the foods tempe, soy sauce and saké. In industrial solid-state fermentation, the substrate usually

  17. Morphological and enzymatic response of the thermotolerant fungus Fomes sp. EUM1 in solid state fermentation under thermal stress.

    Science.gov (United States)

    Ordaz-Hernández, Armando; Ortega-Sánchez, Eric; Montesinos-Matías, Roberto; Hernández-Martínez, Ricardo; Torres-Martínez, Daniel; Loera, Octavio

    2016-08-01

    Thermotolerance of the fungus Fomes sp. EUM1 was evaluated in solid state fermentation (SSF). This thermotolerant strain improved both hyphal invasiveness (38%) and length (17%) in adverse thermal conditions exceeding 30°C and to a maximum of 40°C. In contrast, hyphal branching decreased by 46% at 45°C. The production of cellulases over corn stover increased 1.6-fold in 30°C culture conditions, xylanases increased 2.8-fold at 40°C, while laccase production improved 2.7-fold at 35°C. Maximum production of lignocellulolytic enzymes was obtained at elevated temperatures in shorter fermentation times (8-6 days), although the proteases appeared as a thermal stress response associated with a drop in lignocellulolytic activities. Novel and multiple isoenzymes of xylanase (four bands) and cellulase (six bands) were secreted in the range of 20-150 kDa during growth in adverse temperature conditions. However, only a single laccase isoenzyme (46 kDa) was detected. This is the first report describing the advantages of a thermotolerant white-rot fungus in SSF. These results have important implications for large-scale SSF, where effects of metabolic heat are detrimental to growth and enzyme production, which are severely affected by the formation of high temperature gradients. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Thermal decomposition of lanthanides (III) and yttrium (III) solid complexes from ethyl ene diamine tetraacetic acid

    International Nuclear Information System (INIS)

    Mercadante, A.

    1991-01-01

    Solid state compounds of lanthanides (III) and yttrium derived from ethyl ene diamine tetraacetic acid were prepared from respective basic carbonates, that were neutralized with EDTA stoichiometry quantities. Complexometry with EDTA, thermogravimetry (TG), differential thermal analysis (DTA) and X-ray diffraction have been used in the study of these compounds. The results of complexometry with EDTA as well as TG and DTA curves bed to the stoichiometry of these compounds the following general formula is obeyed: H[Ln(EDTA]. n H 2 O. X-ray powder patterns of these compounds permitted to establish two isomorphous series. The DTA ant TG curves allowed us to study the dehydration process, the thermal stability and thermal decomposition of these compounds. (C.G.C.)

  19. Exploration and exploitation of homologous series of bis(acrylamidoalkanes containing pyridyl and phenyl groups: β-sheet versus two-dimensional layers in solid-state photochemical [2 + 2] reactions

    Directory of Open Access Journals (Sweden)

    Mousumi Garai

    2015-09-01

    Full Text Available The homologous series of phenyl and pyridyl substituted bis(acrylamidoalkanes have been synthesized with the aim of systematic analysis of their crystal structures and their solid-state [2 + 2] reactivities. The changes in the crystal structures with respect to a small change in the molecular structure, that is by varying alkyl spacers between acrylamides and/or by varying the end groups (phenyl, 2-pyridyl, 3-pyridyl, 4-pyridyl on the C-terminal of the amide, were analyzed in terms of hydrogen-bonding interference (N—H...Npy versus N—H...O=C and network geometries. In this series, a greater tendency towards the formation of N—H...O hydrogen bonds (β-sheets and two-dimensional networks over N—H...N hydrogen bonds was observed. Among all the structures seven structures were found to have the required alignments of double bonds for the [2 + 2] reaction such that the formations of single dimer, double dimer and polymer are facilitated. However, only four structures were found to exhibit such a solid-state [2 + 2] reaction to form a single dimer and polymers. The two-dimensional hydrogen-bonding layer via N—H...O hydrogen bonds was found to promote solid-state [2 + 2] photo-polymerization in a single-crystal-to-single-crystal manner. Such two-dimensional layers were encountered only when the spacer between acryl amide moieties is butyl. Only four out of the 16 derivatives were found to form hydrates, two each from 2-pyridyl and 4-pyridyl derivatives. The water molecules in these structures govern the hydrogen-bonding networks by the formation of an octameric water cluster and one-dimensional zigzag water chains. The trends in the melting points and densities were also analyzed.

  20. BOOK REVIEW: Solid State Physics: An Introduction

    Science.gov (United States)

    Jakoby, Bernhard

    2009-07-01

    There's a wealth of excellent textbooks on solid state physics. The author of the present book is well aware of this fact and does not attempt to write just another one. Rather, he has provided a very compact introduction to solid state physics for third-year students. As we are faced with the continuous appearance interdisciplinary fields and associated study curricula in natural and engineering sciences (biophysics, mechatronics, etc), a compact text in solid state physics would be appreciated by students of these disciplines as well. The book features 11 chapters where each is provided with supplementary discussion questions and problems. The first chapters deal with a review of chemical bonding mechanisms, crystal structures and mechanical properties of solids, which are brief but by no means superficial. The following, somewhat more detailed chapter on thermal properties of lattices includes a nice introduction to phonons. The foundations of solid state electronics are treated in the next three chapters. Here the author first discusses the classical treatment of electronic behaviour in metals (Drude model) and continues with a quantum-theoretical approach starting with the free-electron model and leading to the band structures in conductive solids. The next chapter is devoted to semiconductors and ends with a brief but, with respect to the topical scope, adequate discussion of semiconductor devices. The classical topics of magnetic and dielectric behaviour are treated in the sequel. The book closes with a chapter on superconductivity and a brief chapter covering the modern topics of quantum confinement and aspects of nanoscale physics. In my opinion, the author has succeeded in creating a very concise yet not superficial textbook. The account presented often probes subjects deep enough to lay the basis for a thorough understanding, preparing the reader for more specialized textbooks. For instance, I think that this book may serve as an excellent first

  1. Reactions of Ground State Nitrogen Atoms N(4S) with Astrochemically-Relevant Molecules on Interstellar Dusts

    Science.gov (United States)

    Krim, Lahouari; Nourry, Sendres

    2015-06-01

    In the last few years, ambitious programs were launched to probe the interstellar medium always more accurately. One of the major challenges of these missions remains the detection of prebiotic compounds and the understanding of reaction pathways leading to their formation. These complex heterogeneous reactions mainly occur on icy dust grains, and their studies require the coupling of laboratory experiments mimicking the extreme conditions of extreme cold and dilute media. For that purpose, we have developed an original experimental approach that combine the study of heterogeneous reactions (by exposing neutral molecules adsorbed on ice to non-energetic radicals H, OH, N...) and a neon matrix isolation study at very low temperatures, which is of paramount importance to isolate and characterize highly reactive reaction intermediates. Such experimental approach has already provided answers to many questions raised about some astrochemically-relevant reactions occurring in the ground state on the surface of dust grain ices in dense molecular clouds. The aim of this new present work is to show the implication of ground state atomic nitrogen on hydrogen atom abstraction reactions from some astrochemically-relevant species, at very low temperatures (3K-20K), without providing any external energy. Under cryogenic temperatures and with high barrier heights, such reactions involving N(4S) nitrogen atoms should not occur spontaneously and require an initiating energy. However, the detection of some radicals species as byproducts, in our solid samples left in the dark for hours at 10K, proves that hydrogen abstraction reactions involving ground state N(4S) nitrogen atoms may occur in solid phase at cryogenic temperatures. Our results show the efficiency of radical species formation stemming from non-energetic N-atoms and astrochemically-relevant molecules. We will then discuss how such reactions, involving nitrogen atoms in their ground states, might be the first key step

  2. Solid State Photovoltaic Research Branch

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.

  3. Thermal testing of solid neutron shielding materials

    International Nuclear Information System (INIS)

    Boonstra, R.H.

    1990-03-01

    The GA-4 and GA-9 spent fuel shipping casks employ a solid neutron shielding material. During a hypothetical thermal accident, any combustion of the neutron shield must not compromise the ability of the cask to contain the radioactive contents. A two-phase thermal testing program was carried out to assist in selecting satisfactory shielding materials. In the first phase, small-scale screening tests were performed on nine candidate materials using ASTM procedures. From these initial results, three of the nine candidates were chosen for inclusion in the second phase of testing, These materials were Bisco Products NS-4-FR, Reactor Experiments 201-1, and Reactor Experiments 207. In the second phase, each selected material was fabricated into a test article which simulated a full-scale of neutron shield from the cask. The test article was heated in an environmental prescribed by NRC regulations. Results of this second testing phase showed that all three materials are thermally acceptable

  4. Thermal testing of solid neutron shielding materials

    International Nuclear Information System (INIS)

    Boonstra, R.N.

    1990-01-01

    The GA-4 and GA-9 spent fuel shipping casks employ a solid neutron shielding material. During a hypothetical thermal accident, any combustion of the neutron shield must not compromise the ability of the cask to contain the radioactive contents. A two-phase thermal testing program was carried out to assist in selecting satisfactory shielding materials. In the first phase, small-scale screening tests were performed on nine candidate materials using ASTM procedures. From these initial results, three of the nine candidates were chosen for inclusion in the second phase of testing. These materials were Bisco Products NS-4-FR, Reactor Experiments 201-1, and Reactor Experiments 207. In the second phase, each selected material was fabricated into a test article which simulated a full-scale section of neutron shield from the cask. The test article was heated in an environment prescribed by NRC regulations. Results of this second testing phase show that all three materials are thermally acceptable

  5. Detection of different oxidation states of individual manganese porphyrins during their reaction with oxygen at a solid/liquid interface.

    Science.gov (United States)

    den Boer, Duncan; Li, Min; Habets, Thomas; Iavicoli, Patrizia; Rowan, Alan E; Nolte, Roeland J M; Speller, Sylvia; Amabilino, David B; De Feyter, Steven; Elemans, Johannes A A W

    2013-07-01

    Manganese porphyrins have been extensively investigated as model systems for the natural enzyme cytochrome P450 and as synthetic oxidation catalysts. Here, we report single-molecule studies of the multistep reaction of manganese porphyrins with molecular oxygen at a solid/liquid interface, using a scanning tunnelling microscope (STM) under environmental control. The high lateral resolution of the STM, in combination with its sensitivity to subtle differences in the electronic properties of molecules, allowed the detection of at least four distinct reaction species. Real-space and real-time imaging of reaction dynamics enabled the observation of active sites, immobile on the experimental timescale. Conversions between the different species could be tuned by the composition of the atmosphere (argon, air or oxygen) and the surface bias voltage. By means of extensive comparison of the results to those obtained by analogous solution-based chemistry, we assigned the observed species to the starting compound, reaction intermediates and products.

  6. mathematical model of thermal explosion, the dual variational formulation of nonlinear problem, alternative functional

    Directory of Open Access Journals (Sweden)

    V. S. Zarubin

    2016-01-01

    Full Text Available A temperature state of the solid body may depend both on the conditions of heat exchange with external environment surrounding its surface and on the energy release within the body volume, caused, for example, by the processes in nuclear reactor elements or exothermic chemical reactions, absorption of penetrating radiation energy or transformation of a part of the electrical power into heat with flowing electric current (so-called Joule heat.If with growing temperature the intensity of bulk power density increases, a limited steady temperature state can emerge at which heat extracted to the body surface and released within its volume reaches maximum. Thus, small increments of temperature lead to an increase of heat release, which can not be extracted to the body surface by conduction without further temperature increase. As a result, the steady temperature distribution in the body becomes impossible that determines the state of the thermal explosion, so named due to the fact that in this case the appropriate mathematical model predicts an unlimited temperature increase.A lot of published papers and monographs concerning the study of the combustion and explosion processes in a stationary medium analyse the thermal explosion state. The most famous papers consider a mathematical model to describe a temperature distribution in the case when heat release is because of exothermic chemical reactions the rate of which increases with temperature growth. The dependence of the chemical reaction rate on temperature is usually described by the exponential Arrhenius law, which makes it necessary to consider an essentially nonlinear mathematical model containing differential equation, which includes the term, nonlinearly rising with increasing temperature. Even with simplifying assumptions, this model allows an exact closed form solution only in the case of one-dimensional temperature distributions in the two areas of the canonical form: in the plate, infinite

  7. Zr doping effect with low-cost solid-state reaction method to synthesize submicron Li4Ti5O12 anode material

    Science.gov (United States)

    Seo, Inseok; Lee, Cheul-Ro; Kim, Jae-Kwang

    2017-09-01

    To improve the electrochemical properties, fine Zr-doping Li4Ti5O12 anode materials for rechargeable lithium batteries with a uniform particle size distribution were synthesized by a modified solid-state reaction using fine Li2CO3 and TiO2 (anatase) powders as precursors with a Li:Ti molar ratio of 4:5. The use of fine Li2CO3 and TiO2 (anatase) powders as precursors prevented the formation of ZrO2 at 0.1 mol Zr-doping. XRD analysis revealed that the substitution of Zr for Ti leads to the increase of lattice parameters, allowing improved Li diffusion. The discharge capacity retention increased slightly with Zr-doping and the 0.1 mol Zr-doped Li4Ti5O12 electrode achieved 99% retention of discharge capacity.

  8. Efficiency and threshold pump intensity of CW solar-pumped solid-state lasers

    Science.gov (United States)

    Hwang, In H.; Lee, Ja H.

    1991-01-01

    The authors consider the relation between the threshold pumping intensity, the material properties, the resonator parameters, and the ultimate slope efficiencies of various solid-state laser materials for solar pumping. They clarify the relation between the threshold pump intensity and the material parameters and the relation between the ultimate slope efficiency and the laser resonator parameters such that a design criterion for the solar-pumped solid-state laser can be established. Among the laser materials evaluated, alexandrite has the highest slope efficiency of about 12.6 percent; however, it does not seem to be practical for a solar-pumped laser application because of its high threshold pump intensity. Cr:Nd:GSGG is the most promising for solar-pumped lasing. Its threshold pump intensity is about 100 air-mass-zero (AM0) solar constants and its slope efficiency is about 12 percent when thermal deformation is completely prevented.

  9. Biredox ionic liquids with solid-like redox density in the liquid state for high-energy supercapacitors.

    Science.gov (United States)

    Mourad, Eléonore; Coustan, Laura; Lannelongue, Pierre; Zigah, Dodzi; Mehdi, Ahmad; Vioux, André; Freunberger, Stefan A; Favier, Frédéric; Fontaine, Olivier

    2017-04-01

    Kinetics of electrochemical reactions are several orders of magnitude slower in solids than in liquids as a result of the much lower ion diffusivity. Yet, the solid state maximizes the density of redox species, which is at least two orders of magnitude lower in liquids because of solubility limitations. With regard to electrochemical energy storage devices, this leads to high-energy batteries with limited power and high-power supercapacitors with a well-known energy deficiency. For such devices the ideal system should endow the liquid state with a density of redox species close to the solid state. Here we report an approach based on biredox ionic liquids to achieve bulk-like redox density at liquid-like fast kinetics. The cation and anion of these biredox ionic liquids bear moieties that undergo very fast reversible redox reactions. As a first demonstration of their potential for high-capacity/high-rate charge storage, we used them in redox supercapacitors. These ionic liquids are able to decouple charge storage from an ion-accessible electrode surface, by storing significant charge in the pores of the electrodes, to minimize self-discharge and leakage current as a result of retaining the redox species in the pores, and to raise working voltage due to their wide electrochemical window.

  10. Catalytic and Gas-Solid Reactions Involving HCN over Limestone

    DEFF Research Database (Denmark)

    Jensen, Anker; Johnsson, Jan Erik; Dam-Johansen, Kim

    1997-01-01

    In coal-fired combustion systems solid calcium species may be present as ash components or limestone added to the combustion chamber. In this study heterogeneous reactions involving HCN over seven different limestones were investigated in a laboratory fixed-bed quartz reactor at 873-1,173 K...

  11. Recent Advances in Fast Ion Conducting Materials and Devices - Proceedings of the 2nd Asian Conference on Solid State Ionics

    Science.gov (United States)

    Chowdari, B. V. R.; Liu, Qingguo; Chen, Liquan

    * Measurement of Sulfur Concentration with Zirconia-Based Electrolyte Cell in Molten Iron * Influence of SO2 on the Conductivity of Calcia Stabilized Zirconia * Reactions between YSZ and La1-xCaxMnO3 as a Cathode for SOFC * Preparation and Electrical Properties of Lithium β''-Alumina * Influence of Lithia Content on Properties of β''-Alumina Ceramics * Electrical Conductivity of Solid Solutions of Na2SO4 with Na2SeO4 * Effect of Antagonist XO42- = MoO42- and WO42- Ion Substitution on the Electrical Conductivity of Li2SO4 : Li2CO3 Eutectic System * Study on the Electrical Properties and Structure of Multicrystal Materials Li5+xGe1-xCrxV3O12 * Preliminary Study on Synthesis of Silver Zirconium Silicophosphates by Sol - Gel Process * Sodium Ion Conduction in Iron(III) Exchanged Y Zeolite * Electrical Properties of V5O9+x (x = 0, 1) and CuxV5O9.1 * Electrical Properties of the Tetragonal ZrO2 Stabilized with CeO2, CeO2 + Gd2O3 * Study of Preparation and Ionic Conduction of Doped Barium Cerate Perovskite * Preparing Fine Alumina Powder by Homogeneous Precipitation Method for Fabricating β''-Al2O3 * Amorphous Lithium Ion Conductors in Li2S-SiS2-LiBO2 System * Mixed Alkali Effect of Glass Super Ionic Conductors * Electrical Property and Phase Separation, Crystallization Behavior of A Cu+-Conducting Glass * Investigation of Phase Separation and Crystallization for 0.4CuI-0.3 Cu2O-0.3P2O5 Glass by SEM and XRD * Study on the Lithium Solid Electrolytes of Li3N-LiX(X = F, Cl, Br, I)-B2O3 Ternary Systems * Synthesis and Characterization of the Li2O : P2O5 : WO3 Glasses * The Electrochromic Properties of Electrodeposited Ni-O Films in Nonaqueous Electrolytes * All Solid-State WO3-MnO2 Based Electrochromic Window * Electrochromism in Nickel Oxide Films * E S R of X-Irradiated Melt Quenched Li2SO4 * Mixed-Alkali Effect in the Li2O-Na2O-TeO2 Glass System * Electrical and Thermal Studies on Silver Tellurite Glasses * Late Entries (Invited Papers) * Proton Conducting Polymers * Light

  12. Solid-state NMR basic principles and practice

    CERN Document Server

    Apperley, David C; Hodgkinson, Paul

    2014-01-01

    Nuclear Magnetic Resonance (NMR) has proved to be a uniquely powerful and versatile tool for analyzing and characterizing chemicals and materials of all kinds. This book focuses on the latest developments and applications for "solid-state" NMR, which has found new uses from archaeology to crystallography to biomaterials and pharmaceutical science research. The book will provide materials engineers, analytical chemists, and physicists, in and out of lab, a survey of the techniques and the essential tools of solid-state NMR, together with a practical guide on applications. In this concise introduction to the growing field of solid-state nuclear magnetic resonance spectroscopy The reader will find: * Basic NMR concepts for solids, including guidance on the spin-1/2 nuclei concept * Coverage of the quantum mechanics aspects of solid state NMR and an introduction to the concept of quadrupolar nuclei * An understanding relaxation, exchange and quantitation in NMR * An analysis and interpretation of NMR data, with e...

  13. State-of-the-Art Solid Waste Management Life-Cycle Modeling Workshop

    DEFF Research Database (Denmark)

    Damgaard, Anders; Levis, James W.

    There are many alternatives for the management of solid waste including recycling, biological treatment, thermal treatment and landfill disposal. In many cases, solid waste management systems include the use of several of these processes. Solid waste life-cycle assessment models are often used...... to evaluate the environmental consequences of various waste management strategies. The foundation of every life-cycle model is the development and use of process models to estimate the emissions from solid waste unit processes. The objective of this workshop is to describe life-cycle modeling of the solid...... waste processes and systems. The workshop will begin with an introduction to solid waste life-cycle modeling and available models, which will be followed by sessions on life-cycle process modeling for individual processes (e.g., landfills, biological treatment, and thermal treatment). The first part...

  14. The Kapitza thermal boundary resistance between two solids

    International Nuclear Information System (INIS)

    Andersen, A.C.

    1981-01-01

    In this article, the author develops a model of the Kapitza resistance between two solids in which this resistance is seen to be related to the refraction of thermal phonons at the interface, which is a function of the accoustic properties of the two solids. By calculating a kapitza boundary resistance for the two solids in an ideal case (with ideal temperature, ideal interface, and phonon scattering produced only by the interface) and then producing a summation of the three phonon modes, the angles of incidence, and the phonon frequencies, the author produces an equation which expresses the resistance; this equation is known as the accoustic-mis-match model. By then removing the conditions of ideality and adjusting the equation accordingly, the author finds that the acoustic mismatch model is successful in describing the resistance behavior

  15. Influence of light masonry mortar on the thermal insulation of a solid brick wall

    Energy Technology Data Exchange (ETDEWEB)

    Kupke, C

    1980-12-01

    For calculations of the thermal insulation of structural components according to DIN 4108 and to the Thermal Insulation Ordinance, characteristic data of thermal conductivity are used which are contained in DIN 4108 and in the Bundesanzeiger in Supplements to the publication of material characteristics for the calculation of thermal insulation according to the Thermal Insulation Ordinance. For masonry, this value is equivalent to the thermal conductivity of the bricks, including mortar joints. The mortar considered is standard mortar, group II, according to DIN 1053. In the last few years, in order to improve the thermal insulation, mortars of low thermal conductivity and low volume weight - so-called light masonry mortars - have been used to an increasing extent. The improvement in thermal conductivity as compared with standard mortar is referred to as ..delta..lambda; it depends mostly on the thermal conductivity of the light mortar and the bricks. In the article, the laws governing the influence of light masonry mortar on the thermal insulation of masonry of solid bricks and solid blocks are reviewed.

  16. Thermal conductivity and thermal diffusivity of solid UO2

    International Nuclear Information System (INIS)

    Fink, J.K.; Chasanov, M.G.; Leibowitz, L.

    1981-06-01

    New equations for the thermal conductivity of solid UO 2 were derived based upon a nonlinear least squares fit of the data available in the literature. In the development of these equations, consideration was given to their thermodynamic consistency with heat capacity and density and theoretical consistency with enthalpy and heat capacity. Consistent with our previous treatment of enthalpy and heat capacity, 2670 K was selected as the temperature of a phase transition. A nonlinear equation, whose terms represent contributions due to phonons and electrons, was selected for the temperature region below 2670 K. Above 2670 K, the data were fit by a linear equation

  17. Preparation, characterization and thermal properties of PMMA/n-heptadecane microcapsules as novel solid-liquid microPCM for thermal energy storage

    International Nuclear Information System (INIS)

    Sari, Ahmet; Alkan, Cemil; Karaipekli, Ali

    2010-01-01

    This study is focused on the preparation, characterization and thermal properties of microencapsulated n-heptadecane with polymethylmethacrylate shell. The PMMA/heptadecane microcapsules were synthesized as novel solid-liquid microencapsulated phase change material (microPCMs) by emulsion polymerization method. The chemical and thermal characterization of the microPCMs were investigated using scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). The diameters of microPCMs were found in the narrow range (0.14-0.40 μm) under the stirring speed of 2000 rpm. The spherical surfaces of microPCMs were smooth and compact. The DSC results show that microPCMs have good energy storage capacity. Thermal cycling test showed that the microPCMs have good thermal reliability with respect to the changes in their thermal properties after repeated 5000 thermal cycling. TGA analyses also indicated that the microPCMs degraded in three steps and have good thermal stability. Based on all results, it can be considered that the PMMA/heptadecane microcapsules as novel solid-liquid microPCMs have good energy storage potential.

  18. Infrared X-ray and thermal analysis of terbium soaps

    International Nuclear Information System (INIS)

    Mehrotra, K.N.; Sharma, N.

    1996-01-01

    Terbium sops (laureate, myristate and palmitate) were synthesized by direct metathesis of corresponding potassium soap with an aqueous solution of terbium nitrate. The physico-chemical characteristics of soaps in solid state were investigated by IR spectra, X-ray diffraction patterns and TGA measurements. The IR results revealed that the fatty acids exist in dimeric state through hydrogen bonding while the soaps possess partial ionic character. The X-ray analysis showed that the soaps have double layer structure with molecular axes slightly inclined to the basal plane. The thermal analysis suggested that the decomposition of soaps occur in two steps. The energy of activation, order of reaction and various kinetic parameters (i.e. frequency factor, entropy of activation and free energy) for the thermal decomposition of soaps were evaluated. (author). 26 refs, 4 figs, 4 tabs

  19. Photoemission from solids: the transition from solid-state to atomic physics

    International Nuclear Information System (INIS)

    Shirley, D.A.

    1980-08-01

    As the photon energy is increased, photoemission from solids undergoes a slow transition from solid-state to atomic behavior. However, throughout the energy range hν = 10 to 1000 eV or higher both types of phenomena are present. Thus angle-resolved photoemission can only be understood quantitatively if each experimenter recognizes the presence of band-structure, photoelectron diffraction, and photoelectron asymmetry effects. The quest for this understanding will build some interesting bridges between solid-state and atomic physics and should also yield important new insights about the phenomena associated with photoemission

  20. Lithium-ion transport in inorganic solid state electrolyte

    International Nuclear Information System (INIS)

    Gao Jian; Li Hong; Zhao Yu-Sheng; Shi Si-Qi

    2016-01-01

    An overview of ion transport in lithium-ion inorganic solid state electrolytes is presented, aimed at exploring and designing better electrolyte materials. Ionic conductivity is one of the most important indices of the performance of inorganic solid state electrolytes. The general definition of solid state electrolytes is presented in terms of their role in a working cell (to convey ions while isolate electrons), and the history of solid electrolyte development is briefly summarized. Ways of using the available theoretical models and experimental methods to characterize lithium-ion transport in solid state electrolytes are systematically introduced. Then the various factors that affect ionic conductivity are itemized, including mainly structural disorder, composite materials and interface effects between a solid electrolyte and an electrode. Finally, strategies for future material systems, for synthesis and characterization methods, and for theory and calculation are proposed, aiming to help accelerate the design and development of new solid electrolytes. (topical review)

  1. Advances in Solid State Physics

    CERN Document Server

    Haug, Rolf

    2008-01-01

    The present volume 47 of the Advances in Solid State Physics contains the written version of a large number of the invited talks of the 2007 Spring Meeting of the Arbeitskreis Festkörperphysik which was held in Regensburg, Germany, from March 26 to 30, 2007 in conjunction with the 71st Annual Meeting of the Deutsche Physikalische Gesellschaft.It gives an overview of the present status of solid state physics where low-dimensional systems such as quantum dots and quantum wires are dominating. The importance of magnetic materials is reflected by the large number of contributions in the part dealing with ferromagnetic films and particles. One of the most exciting achievements of the last couple of years is the successful application of electrical contacts to and the investigation of single layers of graphene. This exciting physics is covered in Part IV of this book. Terahertz physics is another rapidly moving field which is presented here by five contributions. Achievements in solid state physics are only rarely...

  2. Atomic layer deposition of lithium phosphates as solid-state electrolytes for all-solid-state microbatteries

    International Nuclear Information System (INIS)

    Wang, Biqiong; Liu, Jian; Sun, Qian; Li, Ruying; Sun, Xueliang; Sham, Tsun-Kong

    2014-01-01

    Atomic layer deposition (ALD) has been shown as a powerful technique to build three-dimensional (3D) all-solid-state microbattery, because of its unique advantages in fabricating uniform and pinhole-free thin films in 3D structures. The development of solid-state electrolyte by ALD is a crucial step to achieve the fabrication of 3D all-solid-state microbattery by ALD. In this work, lithium phosphate solid-state electrolytes were grown by ALD at four different temperatures (250, 275, 300, and 325 °C) using two precursors (lithium tert-butoxide and trimethylphosphate). A linear dependence of film thickness on ALD cycle number was observed and uniform growth was achieved at all four temperatures. The growth rate was 0.57, 0.66, 0.69, and 0.72 Å/cycle at deposition temperatures of 250, 275, 300, and 325 °C, respectively. Furthermore, x-ray photoelectron spectroscopy confirmed the compositions and chemical structures of lithium phosphates deposited by ALD. Moreover, the lithium phosphate thin films deposited at 300 °C presented the highest ionic conductivity of 1.73 × 10 −8 S cm −1 at 323 K with ∼0.51 eV activation energy based on the electrochemical impedance spectroscopy. The ionic conductivity was calculated to be 3.3 × 10 −8 S cm −1 at 26 °C (299 K). (paper)

  3. Some solid state properties of LiF:Mg,Cu,P TL-materials

    Energy Technology Data Exchange (ETDEWEB)

    Prokert, K [Dresden Univ. of Technology (Georgia). Inst. of Radiation Protection

    1996-12-31

    This paper describes some investigations of solid state characteristics of a LiF:Mg,Cu,P thermoluminofor. The investigations were carried out with LiF:Mg,Cu,P-thermoluminescence (TL)-material prepared by the chemical institute of the Moscow State University in form of powder and sintered pellets. Following methods were used: (1) Studies of the chemical composition was carried out by x-ray fluorescence analysis with `SPECTRO-X-LAB`-equipment with Rh-anode, B{sub 4}C-polarizator, LN{sub 2}-cooled 30 mm{sup 2} Si(Li)-detector with Be-window (energy resolution 155 keV for Mn-k{sub {alpha}}-radiation). The software of the equipment permits a qualitative and quantitative determination of elements with atomic numbers >10; (2) investigations of the crystal structure were taken by x-ray-diffractometry with a SIEMENS-diffractometer D 500 using Cu-k{sub {alpha}}-radiation. The integrated software permits to analyze the crystalline phases using the data of the measured material by comparison with standards spectra of various pure substances. The results of determination of the chemical composition and the crystal structure show that in the thermoluminofor LiF:Mg,Cu,P, besides the basic material LiF also Li{sub 3}PO{sub 4}- and Li{sub 4}P{sub 2}O{sub 7}-crystal regions exists. The occurrence of the two lithium phosphate phases follow from the high ammonium phosphate content in the mixture for the thermoluminofor production. The formation of the various lithium phosphates depends from state of dehydration of phosphoric acids, created by thermal decomposition of NH{sub 4}H{sub 2}PO{sub 4} before their reactions with LiF start. Therefore the content of these compounds can differ if thermoluminofors are prepared under various conditions. The maintenance of the needed equilibrium of special structures in the material depends on the preparation procedure, on the reading and annealing methods. Typically for such an equilibrium is its poor thermal stability. (Abstract Truncated)

  4. Solid-state membrane module

    Science.gov (United States)

    Gordon, John Howard [Salt Lake City, UT; Taylor, Dale M [Murray, UT

    2011-06-07

    Solid-state membrane modules comprising at least one membrane unit, where the membrane unit has a dense mixed conducting oxide layer, and at least one conduit or manifold wherein the conduit or manifold comprises a dense layer and at least one of a porous layer and a slotted layer contiguous with the dense layer. The solid-state membrane modules may be used to carry out a variety of processes including the separating of any ionizable component from a feedstream wherein such ionizable component is capable of being transported through a dense mixed conducting oxide layer of the membrane units making up the membrane modules. For ease of construction, the membrane units may be planar.

  5. LBM estimation of thermal conductivity in meso-scale modelling

    International Nuclear Information System (INIS)

    Grucelski, A

    2016-01-01

    Recently, there is a growing engineering interest in more rigorous prediction of effective transport coefficients for multicomponent, geometrically complex materials. We present main assumptions and constituents of the meso-scale model for the simulation of the coal or biomass devolatilisation with the Lattice Boltzmann method. For the results, the estimated values of the thermal conductivity coefficient of coal (solids), pyrolytic gases and air matrix are presented for a non-steady state with account for chemical reactions in fluid flow and heat transfer. (paper)

  6. Direct measurement of thermal conductivity in solid iron at planetary core conditions.

    Science.gov (United States)

    Konôpková, Zuzana; McWilliams, R Stewart; Gómez-Pérez, Natalia; Goncharov, Alexander F

    2016-06-02

    The conduction of heat through minerals and melts at extreme pressures and temperatures is of central importance to the evolution and dynamics of planets. In the cooling Earth's core, the thermal conductivity of iron alloys defines the adiabatic heat flux and therefore the thermal and compositional energy available to support the production of Earth's magnetic field via dynamo action. Attempts to describe thermal transport in Earth's core have been problematic, with predictions of high thermal conductivity at odds with traditional geophysical models and direct evidence for a primordial magnetic field in the rock record. Measurements of core heat transport are needed to resolve this difference. Here we present direct measurements of the thermal conductivity of solid iron at pressure and temperature conditions relevant to the cores of Mercury-sized to Earth-sized planets, using a dynamically laser-heated diamond-anvil cell. Our measurements place the thermal conductivity of Earth's core near the low end of previous estimates, at 18-44 watts per metre per kelvin. The result is in agreement with palaeomagnetic measurements indicating that Earth's geodynamo has persisted since the beginning of Earth's history, and allows for a solid inner core as old as the dynamo.

  7. Oriented solid-state NMR spectrosocpy

    DEFF Research Database (Denmark)

    Bertelsen, Kresten

    This thesis is concerned with driving forward oriented solid-state NMR spectroscopy as a viable technique for studying peptides in membrane bilayers. I will show that structural heterogeneity is an intrinsic part of the peptide/lipid system and that NMR can be used to characterize static...... and dynamic structural features of the peptides and its local surroundings. In fact one need to take into account the dynamical features of the system in order to correctly predict the structure from oriented solid-state NMR spectra.      ...

  8. Monolayer Nickel Cobalt Hydroxyl Carbonate for High Performance All-Solid-State Asymmetric Supercapacitors.

    Science.gov (United States)

    Zhao, Yufeng; Ma, Hongnan; Huang, Shifei; Zhang, Xuejiao; Xia, Meirong; Tang, Yongfu; Ma, Zi-Feng

    2016-09-07

    The emergence of atomically thick nanolayer materials, which feature a short ion diffusion channel and provide more exposed atoms in the electrochemical reactions, offers a promising occasion to optimize the performance of supercapacitors on the atomic level. In this work, a novel monolayer Ni-Co hydroxyl carbonate with an average thickness of 1.07 nm is synthesized via an ordinary one-pot hydrothermal route for the first time. This unique monolayer structure can efficiently rise up the exposed electroactive sites and facilitate the surface dependent electrochemical reaction processes, and thus results in outstanding specific capacitance of 2266 F g(-1). Based on this material, an all-solid-state asymmetric supercapacitor is developed adopting alkaline PVA (poly(vinyl alcohol)) gel (PVA/KOH) as electrolyte, which performs remarkable cycling stability (no capacitance fade after 19 000 cycles) together with promising energy density of 50 Wh kg(-1) (202 μWh cm(-2)) and high power density of 8.69 kW kg(-1) (35.1 mW cm(-2)). This as-assembled all-solid-state asymmetric supercapacitor (AASC) holds great potential in the field of portable energy storage devices.

  9. Chemically-induced solid-state dewetting of thin Au films

    International Nuclear Information System (INIS)

    Gazit, Nimrod; Klinger, Leonid; Rabkin, Eugen

    2017-01-01

    We employed the solid state dewetting technique to produce nanoparticles of silver-gold alloy on a sapphire substrate. We deposited a thin gold layer on the substrate with alloy nanoparticles, and studied its thermal stability at low homological temperatures. We demonstrated that a large number of densely spaced holes form at the initial stages of dewetting of the gold layer with nanoparticles. A similar homogeneous gold film deposited on a bare sapphire substrate remained stable under identical annealing conditions, exhibiting the onset of dewetting at higher temperatures, and with a lower number of holes. We attributed the decreased thermal stability of the gold film deposited on the substrate with the silver-gold nanoparticles to accelerated grooving at the grain boundaries and triple junctions in the film. The grooving process is accelerated by the diffusion fluxes of Au atoms driven from the film towards the nanoparticles by the gradient of chemical potential. We developed a quantitative model of this chemically-induced dewetting process, and discussed its applicability for the design of better catalytic systems. Our work demonstrates that the chemical driving forces have to be reckoned with in the analysis of thermal stability of multicomponent thin films.

  10. Dendritic morphology observed in the solid-state precipitation in binary alloys

    Energy Technology Data Exchange (ETDEWEB)

    Husain, S.W.; Ahmed, M.S.; Qamar, I. [Dr. A.Q. Khan Research Labs., Rawalpindi (Pakistan)

    1999-06-01

    The precipitation of {gamma}{sub 2} phase in Cu-Al {beta}-phase alloys has been observed to occur in the dendritic morphology. Such morphology is rarely observed in the solid-state transformations. Earlier it was reported that the {gamma} precipitates were formed in the dendritic shape when Cu-Zn {beta}-phase alloys were cooled from high temperature. The characteristics of these two alloy systems have been examined to find the factors promoting the dendritic morphology in the solid-state transformations. Rapid bulk diffusion and fast interfacial reaction kinetics would promote such morphology. The kinetics of atom attachment to the growing interface is expected to be fast when crystallographic similarities exist between the parent phase and the precipitate. The authors have predicted the dendritic morphology in the solid-state precipitation in many binary alloy systems simply based on such crystallographic similarities. These alloys include, in addition to Cu-Al and Cu-Zn, the {beta}-phase alloys in Ag-Li, Ag-Zn, Cu-Ga, Au-Zn, and Ni-Zn systems, {gamma}-phase alloys in Cu-Sn and Ag-Cd systems, and {delta}-phase alloys in Au-Cd system. Of these, the alloys in Ag-Zn, Ni-Zn, Ag-Cd, and Cu-Sn systems were prepared and it was indeed found that the precipitates formed in the dendritic shape.

  11. Synthesis of Ca{sub 3}CO{sub 4}O{sub 9} via solid state reaction; Sintese de Ca{sub 3}CO{sub 4}O{sub 9} via reacao no estado solido

    Energy Technology Data Exchange (ETDEWEB)

    Melo, K.P.; Dutra, R.P.S.; Marques, K.A.; Junior, S.M.S.; Brasileiro, C.T.; Coutinho, S.V.C.R.; Souza, T.; Chagas, T.F.; Silva, R.M.; Macedo, D.A., E-mail: kliviamelo@outlook.com [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil)

    2016-07-01

    Solid oxide fuel cells (SOFCs) stand out as the most promising today's energy conversion technologies. In the development of cathode materials for SOFC, calcium cobaltate (Ca3Co4O9, C349) appears as a potential alternative to traditional lanthanum manganites. In this work, C349 was prepared via solid state reaction of stoichiometric mixtures containing CaCO3 from mollusk shells, in natura (M1) and heat treated at 550 ° C (M2), and Co3O4 obtained by citrate method. The M1 and M2 mixtures were calcined at 800 (powder) and 900 ° C (tablets) for 12 h. The crystal structure and phase composition of the powder and the reaction products were studied by X-ray diffraction Rietveld refinement of the diffraction data. The results showed the formation of free C349 secondary stages, showing a good alternative to use waste from seafood shells as raw material for obtaining high-value ceramics.(author)

  12. Reaction paths and equilibrium end-points in solid-solution aqueous-solution systems

    Science.gov (United States)

    Glynn, P.D.; Reardon, E.J.; Plummer, Niel; Busenberg, E.

    1990-01-01

    Equations are presented describing equilibrium in binary solid-solution aqueous-solution (SSAS) systems after a dissolution, precipitation, or recrystallization process, as a function of the composition and relative proportion of the initial phases. Equilibrium phase diagrams incorporating the concept of stoichiometric saturation are used to interpret possible reaction paths and to demonstrate relations between stoichiometric saturation, primary saturation, and thermodynamic equilibrium states. The concept of stoichiometric saturation is found useful in interpreting and putting limits on dissolution pathways, but there currently is no basis for possible application of this concept to the prediction and/ or understanding of precipitation processes. Previously published dissolution experiments for (Ba, Sr)SO4 and (Sr, Ca)C??O3orth. solids are interpreted using equilibrium phase diagrams. These studies show that stoichiometric saturation can control, or at least influence, initial congruent dissolution pathways. The results for (Sr, Ca)CO3orth. solids reveal that stoichiometric saturation can also control the initial stages of incongruent dissolution, despite the intrinsic instability of some of the initial solids. In contrast, recrystallisation experiments in the highly soluble KCl-KBr-H2O system demonstrate equilibrium. The excess free energy of mixing calculated for K(Cl, Br) solids is closely modeled by the relation GE = ??KBr??KClRT[a0 + a1(2??KBr-1)], where a0 is 1.40 ?? 0.02, a1, is -0.08 ?? 0.03 at 25??C, and ??KBr and ??KCl are the mole fractions of KBr and KCl in the solids. The phase diagram constructed using this fit reveals an alyotropic maximum located at ??KBr = 0.676 and at a total solubility product, ???? = [K+]([Cl-] + [Br-]) = 15.35. ?? 1990.

  13. Four-phonon scattering significantly reduces intrinsic thermal conductivity of solids

    Science.gov (United States)

    Feng, Tianli; Lindsay, Lucas; Ruan, Xiulin

    2017-10-01

    For decades, the three-phonon scattering process has been considered to govern thermal transport in solids, while the role of higher-order four-phonon scattering has been persistently unclear and so ignored. However, recent quantitative calculations of three-phonon scattering have often shown a significant overestimation of thermal conductivity as compared to experimental values. In this Rapid Communication we show that four-phonon scattering is generally important in solids and can remedy such discrepancies. For silicon and diamond, the predicted thermal conductivity is reduced by 30% at 1000 K after including four-phonon scattering, bringing predictions in excellent agreement with measurements. For the projected ultrahigh-thermal conductivity material, zinc-blende BAs, a competitor of diamond as a heat sink material, four-phonon scattering is found to be strikingly strong as three-phonon processes have an extremely limited phase space for scattering. The four-phonon scattering reduces the predicted thermal conductivity from 2200 to 1400 W/m K at room temperature. The reduction at 1000 K is 60%. We also find that optical phonon scattering rates are largely affected, being important in applications such as phonon bottlenecks in equilibrating electronic excitations. Recognizing that four-phonon scattering is expensive to calculate, in the end we provide some guidelines on how to quickly assess the significance of four-phonon scattering, based on energy surface anharmonicity and the scattering phase space. Our work clears the decades-long fundamental question of the significance of higher-order scattering, and points out ways to improve thermoelectrics, thermal barrier coatings, nuclear materials, and radiative heat transfer.

  14. Thermal expansion of TRU nitride solid solutions as fuel materials for transmutation of minor actinides

    International Nuclear Information System (INIS)

    Takano, Masahide; Akabori, Mitsuo; Arai, Yasuo; Minato, Kazuo

    2009-01-01

    The lattice thermal expansion of the transuranium nitride solid solutions was measured to investigate the composition dependence. The single-phase solid solution samples of (Np 0.55 Am 0.45 )N, (Pu 0.59 Am 0.41 )N, (Np 0.21 Pu 0.52 Am 0.22 Cm 0.05 )N and (Pu 0.21 Am 0.18 Zr 0.61 )N were prepared by carbothermic nitridation of the respective transuranium dioxides and nitridation of Zr metal through hydride. The lattice parameters were measured by the high temperature X-ray diffraction method from room temperature up to 1478 K. The linear thermal expansion of each sample was determined as a function of temperature. The average thermal expansion coefficients over the temperature range of 293-1273 K for the solid solution samples were 10.1, 11.5, 10.8 and 8.8 x 10 -6 K -1 , respectively. Comparison of these values with those for the constituent nitrides showed that the average thermal expansion coefficients of the solid solution samples could be approximated by the linear mixture rule within the error of 2-3%.

  15. Electron spin resonance of spin-trapped radicals of amines and polyamines. Hydroxyl radical reactions in aqueous solutions and. gamma. radiolysis in the solid state

    Energy Technology Data Exchange (ETDEWEB)

    Mossoba, M.M.; Rosenthal, I.; Riesz, P. (National Cancer Inst., Bethesda, MD (USA))

    1982-06-15

    The reactions of hydroxyl radicals with methylamine, dimethylamine, trimethylamine, diethylamine, sec-butylamine, ethylene-diamine, 1,3-diaminopropane, putrescine, cadaverine, 1,7-diaminoheptane, ornithine, spermidine, spermine, agmatine, and arcaine in aqueous solutions have been investigated by spin-trapping and esr. Hydroxyl radicals were generated by the uv photolysis of H/sub 2/O/sub 2/ and 2-methyl-2-nitrosopropane (MNP) was used as the spin-trap. The effects of ionizing radiation on the same polyamines in the polycrystalline state were also investigated. The free radicals produced by ..gamma..-radiolysis of these solids at room temperature in the absence of air were identified by dissolution in aqueous solutions of MNP. The predominant reaction of OH radicals with amines and polyamines below pH 7 was the abstraction of hydrogen atoms from a carbon that is not adjacent to the protonated amino group. For agmatine and arcaine which contain guanidinium groups abstraction occurred from the ..cap alpha..-CH. Dimethylamine was oxidized to the dimethylnitroxyl radical by H/sub 2/O/sub 2/ in the dark. ..gamma..-Radiolysis of polyamines in the polycrystalline state generated radicals due to H-abstraction from either the ..cap alpha..-Ch or from a carbon atom in the middle of the alkyl chain. The deamination radical was obtained from ornithine.

  16. Effect of thermal treatment conditions on properties of vanadium molybdenum oxide catalyst in acrolein oxidation reaction to acrylic acid

    International Nuclear Information System (INIS)

    Gorshkova, T.P.; Tarasova, D.V.; Olen'kova, I.P.; Andrushkevich, T.V.; Nikoro, T.A.

    1984-01-01

    The effect of thermal treatment conditions (temperature and gas medium) on properties of vanadium molybdenum oxide catalyst in acrolein oxidation reaction to acrylic acid is investigated. It is shown that active and selective catalysts are formed in the course of thermal decomposition of the drying product of ammonium metavanadate and paramolybdate under the conditions ensuring the vanadium ion reduction up to tetravalent state with conservation of molybdenum oxidation degree equal to 6. It is possible to realize it either by treatment of the catalyst calcinated in the air flow at 300 deg by the reaction mixture at the activation stage or by gas-reducer flow treatment at 280 deg. Thermal treatment in the reducing medium of the oxidized catalyst does not lead to complete regeneration of its properties

  17. Solid state characterization of commercial crystalline and amorphous atorvastatin calcium samples.

    Science.gov (United States)

    Shete, Ganesh; Puri, Vibha; Kumar, Lokesh; Bansal, Arvind K

    2010-06-01

    Atorvastatin calcium (ATC), an anti-lipid BCS class II drug, is marketed in crystalline and amorphous solid forms. The objective of this study was to perform solid state characterization of commercial crystalline and amorphous ATC drug samples available in the Indian market. Six samples each of crystalline and amorphous ATC were characterized using X-ray powder diffractometry (XRPD), differential scanning calorimetry (DSC), thermogravimetric analysis, Karl Fisher titrimetry, microscopy (hot stage microscopy, scanning electron microscopy), contact angle, and intrinsic dissolution rate (IDR). All crystalline ATC samples were found to be stable form I, however one sample possessed polymorphic impurity, evidenced in XRPD and DSC analysis. Amongst the amorphous ATC samples, XRPD demonstrated five samples to be amorphous 'form 27', while, one matched amorphous 'form 23'. Thermal behavior of amorphous ATC samples was compared to amorphous ATC generated by melt quenching in DSC. ATC was found to be an excellent glass former with T(g)/T(m) of 0.95. Residual crystallinity was detected in two of the amorphous samples by complementary use of conventional and modulated DSC techniques. The wettability and IDR of all amorphous samples was found to be higher than the crystalline samples. In conclusion, commercial ATC samples exhibited diverse solid state behavior that can impact the performance and stability of the dosage forms.

  18. Synthesis, characterization and thermal expansion studies on ThO2-SmO1.5 solid solutions

    International Nuclear Information System (INIS)

    Panneerselvam, G.; Antony, M.P.

    2008-01-01

    Full text: A highly homogeneous Th 1-x Sm x O 2 ; 0 ≤ x ≤ 0.8 solid solutions were synthesized by co-precipitation technique and the co-precipitated samples were sintered at 1473 K. Compositions of the solid solutions were characterized by standard wet-chemical analysis. X-ray diffraction measurements were performed in the sintered pellets for structural analysis, lattice parameter calculation and determination of solid solubility of SmO 1.5 in ThO 2 matrix. Bulk and theoretical densities of solid solutions were also determined. A fluorite structure was observed for ThO 2 -SmO 1.5 solid solutions with 0-55.2 mol % SmO 1.5 . Their thermal expansion coefficients were measured using high temperature X-ray diffraction technique. The mean linear thermal expansivity, αm for ThO 2 -SmO 1.5 solid solutions containing 17.9, 41.7 and 52.0 mole percent of SmO 1.5 were determined in the temperature range 298 to 2000 K for the first time. The mean linear thermal expansion coefficients for ThO 2 -SmO 1.5 solid solutions are 10.47x10 -6 K -1 , 11.16x10 -6 K -1 and 11.45x10 -6 K -1 , respectively. The percentage linear thermal expansion in this temperature range, for ThO 2 -SmO 1.5 solid solutions containing 17.9, 41.7 and 52.0 mol % SmO 1.5 are 1.82,1.94 and 1.99 respectively. It is suggested that the solid solutions are stable up to 2000 K. It is also suggested that the effect and nature of the dopant are the important parameters influenced in the thermal expansion of the ThO 2

  19. Detection of boron in metal alloys with solid state nuclear track detector by neutron induced autoradiography

    International Nuclear Information System (INIS)

    Ali Nabipour; Hosseini, A.; Afarideh, H.

    2002-01-01

    Neutron induced autoradiography is very useful technique for detection as well as measurement of Boron densities in metal alloys. The method is relatively simple and quite sensitive in comparison with other techniques with resolution in the range of PPM. Using this technique with it is also possible to investigate microscopic scattering of Boron in metal alloys. In comparison with most techniques neutron induced autoradiography has its own difficulties and limitations. In this research measurement of Boron densities and investigation of that diffusion in metal alloys has been carried out. A flat nicely polished Boron doped metal samples is covered with a track detecting plastic (CR-39 solid state nuclear track detector) and exposed to thermal neutron dose. After irradiation the plastic detector have been removed and put in an etching solution. Since the diffusion rate of corrosive solution in those area, which heavy ions have been, produces as the result of nuclear reaction with thermal neutron are more than the other areas, some cavities are formed. The diameter of cavities or tracks cross section are increased with increasing the etching time, to some extent that it is possible to observe the cavities with optical microscopes. The density of tracks on the detector surface is directly related to the Boron concentration in the sample and thermal neutron dose. So by measuring the number of tracks on surface of the detector it would possible to calculate the concentration of Boron in metal samples. (Author)

  20. Mechanism to synthesize a ‘moving optical mark’ at solid-ambient interface for the estimation of thermal diffusivity of solid

    Directory of Open Access Journals (Sweden)

    Settu Balachandar

    2016-01-01

    Full Text Available A novel mechanism is proposed, involving a novel interaction between solid-sample supporting unsteady heat flow with its ambient-humidity; invokes phase transformation of water-vapour molecule and synthesize a ‘moving optical-mark’ at sample-ambient-interface. Under tailored condition, optical-mark exhibits a characteristic macro-scale translatory motion governed by thermal diffusivity of solid. For various step-temperature inputs via cooling, position-dependent velocities of moving optical-mark are measured at a fixed distance. A new approach is proposed. ‘Product of velocity of optical-mark and distance’ versus ‘non-dimensional velocity’ is plotted. The slope reveals thermal diffusivity of solid at ambient-temperature; preliminary results obtained for Quartz-glass is closely matching with literature.

  1. Theoretical analysis of thermal molten metal-water reactions

    International Nuclear Information System (INIS)

    Schwalbe, W.

    1982-01-01

    In experiments with greater masses (kg-scale) two extreme cases had been oberved during the course of reaction when hot melt reacted with a vaporizable cooler liquid. Relatively mild hot interactions with slow pressure build-up and small pressure peak in the reaction volume often occurred but there were also some very violent reactions (steam explosions) where a remarkable portion of thermal energy had been transformed into mechanical energy with high pressure peaks. For the two types of reactions overall models for water as a coolant are developed here. Based on calculations and on comparisons with corresponding experiments it is shown that a relatively mild course of reaction can be explained by a fragmentation of the melt under following violent evaporation of the cooling medium. Pressures only with small reaction volumes up to the MPa range can be found in these reactions. The calculations, for example of Bird and Millington, showed a pressure maximum of 1 MPa after 170 ms of the start of the reaction; this agrees very well with the result of the experiment of 1.08 MPa. (orig./GL) [de

  2. An all-solid-state lithium/polyaniline rechargeable cell

    Science.gov (United States)

    Li, Changzhi; Peng, Xinsheng; Zhang, Borong; Wang, Baochen

    1992-07-01

    The performance of an all-solid-state cell having a lithium negative electrode, a modified polyethylene oxide (PEO)-epoxy resin (ER) electrolyte, and a polyaniline (PAn) positive electrode has been studied using cyclic voltammetry, charge/discharge cycling, and polarization curves at various temperatures. The redox reaction of the PAn electrode at the PAn/modified PEO-ER interface exhibits good reversibility. At 50-80 C, the Li/PEO-ER-LiClO4/PAn cell shows more than 40 charge/discharge cycles, 90 percent charge/discharge efficiency, and 54 W h kg discharge energy density (on PAn weight basis) at 50 micro-A between 2 and 4 V. The polarization performance of the battery improves steadily with increase in temperature.

  3. Solid state ionics: a Japan perspective

    Science.gov (United States)

    Yamamoto, Osamu

    2017-12-01

    The 70-year history of scientific endeavor of solid state ionics research in Japan is reviewed to show the contribution of Japanese scientists to the basic science of solid state ionics and its applications. The term 'solid state ionics' was defined by Takehiko Takahashi of Nagoya University, Japan: it refers to ions in solids, especially solids that exhibit high ionic conductivity at a fairly low temperature below their melting points. During the last few decades of exploration, many ion conducting solids have been discovered in Japan such as the copper-ion conductor Rb4Cu16I7Cl13, proton conductor SrCe1-xYxO3, oxide-ion conductor La0.9Sr0.9Ga0.9Mg0.1O3, and lithium-ion conductor Li10GeP2S12. Rb4Cu16I7Cl13 has a conductivity of 0.33 S cm-1 at 25 °C, which is the highest of all room temperature ion conductive solid electrolytes reported to date, and Li10GeP2S12 has a conductivity of 0.012 S cm-1 at 25 °C, which is the highest among lithium-ion conductors reported to date. Research on high-temperature proton conducting ceramics began in Japan. The history, the discovery of novel ionic conductors and the story behind them are summarized along with basic science and technology.

  4. Electron transfer reactions

    CERN Document Server

    Cannon, R D

    2013-01-01

    Electron Transfer Reactions deals with the mechanisms of electron transfer reactions between metal ions in solution, as well as the electron exchange between atoms or molecules in either the gaseous or solid state. The book is divided into three parts. Part 1 covers the electron transfer between atoms and molecules in the gas state. Part 2 tackles the reaction paths of oxidation states and binuclear intermediates, as well as the mechanisms of electron transfer. Part 3 discusses the theories and models of the electron transfer process; theories and experiments involving bridged electron transfe

  5. Thermal runaway reaction hazards and mechanisms of hydroxylamine with acid/base contaminants

    International Nuclear Information System (INIS)

    Wei Chunyang; Saraf, Sanjeev R.; Rogers, William J.; Sam Mannan, M.

    2004-01-01

    Hydroxylamine (HA) has been involved in two incidents since 1999 because of its thermal instability and incompatibility. In this study, thermal runaway reactions of hydroxylamine with various concentrations of KOH and HCl were studied using the reactive system screening tool (RSST) and automatic pressure tracking adiabatic calorimeter (APTAC). The thermokinetic data, such as onset temperature, heat of reaction, maximum self-heat rate, maximum pressure rate, and non-condensable gas pressure, were compared with those of hydroxylamine solution without added impurity. Our study shows that the thermal decomposition behavior of hydroxylamine is affected by the presence of acid/base, and mixing of hydroxylamine with acid/base may cause thermal decomposition at lower temperatures. Different decomposition pathways can be initiated by hydrogen ion and hydroxide ion. The decomposition mechanisms of hydroxylamine in alkaline and acidic solutions are proposed based on the products, information from the literature, and quantum mechanical calculations. The experimental results are discussed in terms of the proposed reaction mechanisms

  6. Chrystal structure properties of Al-doped Li{sub 4}Ti{sub 5}O{sub 12} synthesized by solid state reaction method

    Energy Technology Data Exchange (ETDEWEB)

    Sandi, Dianisa Khoirum, E-mail: dianisa875@gmail.com; Suryana, Risa, E-mail: rsuryana@staff.uns.ac.id [Department of Physics, Faculty of Mathematics and Natural Sciences, Sebelas Maret University (Indonesia); Priyono, Slamet, E-mail: slam013@lipi.go.id [Physics Research Center (P2F)-LIPI, Puspiptek Area, Serpong, Tangerang (Indonesia)

    2016-02-08

    This research aim is to analyze the effect of Aluminum (Al) doping in the structural properties of Al-doped Li{sub 4}Ti{sub 5}O{sub 12} as anode in lithium ion battery. Al-doped Li{sub 4}Ti{sub 5}O{sub 12} powders were synthesized by solid state reaction method. LiOH.H{sub 2}O, TiO{sub 2}, and Al{sub 2}O{sub 3} were raw materials. These materials were milled for 15 h, calcined at temperature of 750{sup o}C and sintered at temperature of 800{sup o}C. Mole percentage of doping Al (x) was varied at x=0; x=0.025; and x =0.05. Al-doped Li{sub 4}Ti{sub 5}O{sub 12} powders were synthesized by solid state reaction method. X-ray diffraction was employed to determine the structure of Li{sub 4}Ti{sub 5}O{sub 12}. The PDXL software was performed on the x-ray diffraction data to estimate the phase percentage, the lattice parameter, the unit cell volume, and the crystal density. Al-doped Li{sub 4}Ti{sub 5}O{sub 12} has cubic crystal structure. Al-doping at x=0 and x=0.025 does not change the phase as Li{sub 4}Ti{sub 5}O{sub 12} while at x=0.050 the phase changes to the LiTiAlO{sub 4}. The diffraction patterns show that the angle shifted to the right as the increase of x which indicated that Al substitute Ti site. Percentage of Li{sub 4}Ti{sub 5}O{sub 12} phase at x=0 and x=0.025 was 97.8% and 96.8%, respectively. However, the lattice parameters, the unit cell volume, and the crystal density does not change significantly at x=0; x=0.025; and x=0.050. Based on the percentage of Li{sub 4}Ti{sub 5}O{sub 12} phase, the Al-doped Li at x=0 and x=0.025 is promising as a lithium battery anode.

  7. Laminating solution-processed silver nanowire mesh electrodes onto solid-state dye-sensitized solar cells

    KAUST Repository

    Hardin, Brian E.

    2011-06-01

    Solution processed silver nanowire meshes (Ag NWs) were laminated on top of solid-state dye-sensitized solar cells (ss-DSCs) as a reflective counter electrode. Ag NWs were deposited in <1 min and were less reflective compared to evaporated Ag controls; however, AgNW ss-DSC devices consistently had higher fill factors (0.6 versus 0.69), resulting in comparable power conversion efficiencies (2.7%) compared to thermally evaporated Ag control (2.8%). Laminated Ag NW electrodes enable higher throughput manufacturing and near unity material usage, resulting in a cheaper alternative to thermally evaporated electrodes. © 2011 Elsevier B.V. All rights reserved.

  8. Advanced thermally stable jet fuels. Technical progress report, April 1993--June 1993

    Energy Technology Data Exchange (ETDEWEB)

    Schobert, H.H.; Eser, S.; Song, C. [and others

    1993-10-01

    The Penn State program in advanced thermally stable coal-based jet fuels has five broad objectives: (1) development of mechanisms of degradation and solids formation; (2) quantitative measurement of growth of sub-micrometer and micrometer-sized particles suspended in fuels during thermal stressing; (3) characterization of carbonaceous deposits by various instrumental and microscopic methods; (4) elucidation of the role of additives in retarding the formation of carbonaceous solids; and (5) assessment of the potential of production of high yields of cycloalkanes by direct liquefaction of coal. Some of our accomplishments and findings are: The product distribution and reaction mechanisms for pyrolysis of alkylcyclohexanes at 450{degree}C have been investigated in detail. In this report we present results of pyrolysis of cyclohexane and a variety of alkylcyclohexanes in nitrogen atmospheres, along with pseudo-first order rate constants, and possible reaction mechanisms for the origin of major pyrolysis products are presented. Addition of PX-21 activated carbon effectively stops the formation of carbonaceous solids on reactor walls during thermal stressing of JPTS. A review of physical and chemical interactions in supercritical fluids has been completed. Work has begun on thermal stability studies of a second generation of fuel additives, 1,2,3,4-tetrahydro-l-naphthol, 9,10-phenanthrenediol, phthalan, and 1,2-benzenedimethanol, and with careful selection of the feedstock, it is possible to achieve 85--95% conversion of coal to liquids, with 40--50% of the dichloromethane-soluble products being naphthalenes. (Further hydrogenation of the naphthalenes should produce the desired highly stable decalins.)

  9. Development of Lithium Stuffed Garnet-Type Oxide Solid Electrolytes with High Ionic Conductivity for Application to All-Solid-State Batteries

    Directory of Open Access Journals (Sweden)

    Ryoji Inada

    2016-07-01

    Full Text Available All-solid-state lithium-ion battery (LiB is expected as one of the next generation energy storage devices because of their high energy density, high safety and excellent cycle stability. Although oxide-based solid electrolyte materials have rather lower conductivity and poor deformability than sulfide-based one, they have other advantages such as their chemical stability and easiness for handling. Among the various oxide-based SEs, lithium stuffed garnet-type oxide with the formula of Li7La3Zr2O12 (LLZ have been widely studied because of their high conductivity above 10-4 Scm-1 at room temperature, excellent thermal performance and stability against Li metal anode.Here, we present our recent progress for the development of garnet-type solid electrolytes with high conductivity by simultaneous substitution of Ta5+ into Zr4+ site and Ba2+ into La3+ site in LLZ. Li+ concentration was fixed to 6.5 per chemical formulae, so that the formulae of our Li garnet-type oxide is expressed as Li6.5La3-xBaxZr1.5-xTa0.5+xO12 (LLBZT and Ba contents x are changed from 0 to 0.3. As results, all LLBZT samples have cubic garnet structure without containing any secondary phases. The lattice parameters of LLBZT decrease with increasing Ba2+ contents x < 0.10 while increase with x from 0.10 to 0.30, possibly due to the simultaneous change of Ba2+ and Ta5+ substitution levels. Relative densities of LLBZT are in the range between 89% and 93% and not influenced so much by the compositions. From AC impedance spectroscopy measurements, the total (bulk + grain conductivity at 27ºC of LLBZT shows its maximum value of 8.34 x 10-4 S cm-1 at x = 0.10, which is slightly higher than the conductivity (= 7.94 x 10-4 S cm-1 of LLZT without substituting Ba (x = 0. Activation energy of the conductivity tends to become lower by Ba substation, while excess Ba substitution degrades the conductivity in LLBZT. LLBZT has wide electrochemical potential window of 0-6 V vs. Li+/Li and

  10. Detection of urea-induced internal denaturation of dsDNA using solid-state nanopores.

    Science.gov (United States)

    Singer, Alon; Kuhn, Heiko; Frank-Kamenetskii, Maxim; Meller, Amit

    2010-11-17

    The ability to detect and measure dsDNA thermal fluctuations is of immense importance in understanding the underlying mechanisms responsible for transcription and replication regulation. We describe here the ability of solid-state nanopores to detect sub-nanometer changes in DNA structure as a result of chemically enhanced thermal fluctuations. In this study, we investigate the subtle changes in the mean effective diameter of a dsDNA molecule with 3-5 nm solid-state nanopores as a function of urea concentration and the DNA's AT content. Our studies reveal an increase in the mean effective diameter of a DNA molecule of approximately 0.6 nm at 8.7 M urea. In agreement with the mechanism of DNA local denaturation, we observe a sigmoid dependence of these effects on urea concentration. We find that the translocation times in urea are markedly slower than would be expected if the dynamics were governed primarily by viscous effects. Furthermore, we find that the sensitivity of the nanopore is sufficient to statistically differentiate between DNA molecules of nearly identical lengths differing only in sequence and AT content when placed in 3.5 M urea. Our results demonstrate that nanopores can detect subtle structural changes and are thus a valuable tool for detecting differences in biomolecules' environment.

  11. Detection of urea-induced internal denaturation of dsDNA using solid-state nanopores

    International Nuclear Information System (INIS)

    Singer, Alon; Kuhn, Heiko; Frank-Kamenetskii, Maxim; Meller, Amit

    2010-01-01

    The ability to detect and measure dsDNA thermal fluctuations is of immense importance in understanding the underlying mechanisms responsible for transcription and replication regulation. We describe here the ability of solid-state nanopores to detect sub-nanometer changes in DNA structure as a result of chemically enhanced thermal fluctuations. In this study, we investigate the subtle changes in the mean effective diameter of a dsDNA molecule with 3-5 nm solid-state nanopores as a function of urea concentration and the DNA's AT content. Our studies reveal an increase in the mean effective diameter of a DNA molecule of approximately 0.6 nm at 8.7 M urea. In agreement with the mechanism of DNA local denaturation, we observe a sigmoid dependence of these effects on urea concentration. We find that the translocation times in urea are markedly slower than would be expected if the dynamics were governed primarily by viscous effects. Furthermore, we find that the sensitivity of the nanopore is sufficient to statistically differentiate between DNA molecules of nearly identical lengths differing only in sequence and AT content when placed in 3.5 M urea. Our results demonstrate that nanopores can detect subtle structural changes and are thus a valuable tool for detecting differences in biomolecules' environment.

  12. Introduction to solid state electronics

    CERN Document Server

    Wang, FFY

    1989-01-01

    This textbook is specifically tailored for undergraduate engineering courses offered in the junior year, providing a thorough understanding of solid state electronics without relying on the prerequisites of quantum mechanics. In contrast to most solid state electronics texts currently available, with their generalized treatments of the same topics, this is the first text to focus exclusively and in meaningful detail on introductory material. The original text has already been in use for 10 years. In this new edition, additional problems have been added at the end of most chapters. These proble

  13. Solid state physics an introduction

    CERN Document Server

    Hofmann, Philip

    2015-01-01

    A must-have textbook for any undergraduate studying solid state physics. This successful brief course in solid state physics is now in its second edition. The clear and concise introduction not only describes all the basic phenomena and concepts, but also such advanced issues as magnetism and superconductivity. Each section starts with a gentle introduction, covering basic principles, progressing to a more advanced level in order to present a comprehensive overview of the subject. The book is providing qualitative discussions that help undergraduates understand concepts even if they can?t foll

  14. A study of the solid-phase thermal decomposition of NTO using simultaneous thermogravimetric modulated beam mass spectrometry (STMBMS)

    Energy Technology Data Exchange (ETDEWEB)

    Minier, L.; Behrens, R. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility; Burkey, T.J. [Univ. of Memphis, TN (United States). Chemistry Dept.

    1997-01-01

    The solid phase thermal reaction chemistry of NTO between 190 and 250 C is presently being evaluated by utilizing STMBMS, a technique that enables the authors to measure the vapor pressure of NTO and to explore the reaction mechanisms and chemical kinetics associated with the NTO thermal decomposition process. The vapor pressure of NTO is expressed as Log{sub 10} p(torr) = 12.5137 + 6,296.553(1/t{sub k}) and the {Delta}H{sub subl} = 28.71 {+-} 0.07 kcal/mol (120.01 {+-} 0.29 kJ/mol). The pyrolysis of NTO results in the formation of gaseous products and a condensed-phase residue. The identity of the major gaseous products and their origin from within the NTO molecules are determined based on the results from pyrolysis of NTO, NTO-3-{sup 13}C, NTO-1,2-{sup 15}N{sub 2} and NTO-{sup 2}H{sub 2}. Identification of the products show the major gaseous products to be N{sub 2}, CO{sub 2}, NO, HNCO, H{sub 2}O and some N{sub 2}O, CO, HCN and NH{sub 3}. The N{sub 2} is mostly derived from the N-1 and N-2 positions with some being from the N-4 and N-1 or N-2 positions. The CO{sub 2} is derived from both carbons in the NTO molecule in comparable amounts. The residue has an elemental formula of C{sub 2.1}H{sub .26}N{sub 2.9}O and FTIR analysis suggests that the residue is polyurea- and polycarbamate-like in nature. The temporal behaviors of the rates of formation of the gaseous products indicate that the overall thermal decomposition of NTO in the temperature range evaluated involves four major processes: (1) NTO sublimation; (2) an apparent solid-solid phase transition between 190 and 195 C; (3) a decomposition regime induced by the presence of exogenous H{sub 2}O at the onset of decomposition; and (4) a decomposition regime that occurs at the onset of decomposition and continues until the depletion of NTO. Decomposition pathways that are consistent with the data are presented.

  15. Ultrasonic methods in solid state physics

    CERN Document Server

    Truell, John; Elbaum, Charles

    1969-01-01

    Ultrasonic Methods in Solid State Physics is devoted to studies of energy loss and velocity of ultrasonic waves which have a bearing on present-day problems in solid-state physics. The discussion is particularly concerned with the type of investigation that can be carried out in the megacycle range of frequencies from a few megacycles to kilomegacycles; it deals almost entirely with short-duration pulse methods rather than with standing-wave methods. The book opens with a chapter on a classical treatment of wave propagation in solids. This is followed by separate chapters on methods and techni

  16. Annealing effects in solid-state track recorders

    International Nuclear Information System (INIS)

    Gold, R.; Roberts, J.H.; Ruddy, F.H.

    1981-01-01

    Current analyses of the annealing process in Solid State Track Recorders (SSTR) reveal fundamental misconceptions. The use of the Arrhenius equation to describe the decrease in track density resulting from annealing is shown to be incorrect. To overcome these deficiencies, generalized reaction rate theory is used to describe the annealing process in SSTR. Results of annealing experiments are used to guide this theoretical formulation. Within this framework, the concept of energy per etchable defect for SSTR is introduced. A general correlation between sensitivity and annealing susceptibility in SSTR is deduced. In terms of this general theory, the apparent correlation between fission track size and fission track density observed under annealing is readily explained. Based on this theoretical treatment of annealing phenomena, qualitative explanations are advanced for current enigmas in SSTR cosmic ray work

  17. What is Eating Ozone? Thermal Reactions between SO2 And O3: Implications for Icy Environments

    Science.gov (United States)

    Loeffler, Mark J.; Hudson, Reggie L.

    2016-01-01

    Laboratory studies are presented, showing for the first time that thermally driven reactions in solid H2O+SO2+O3 mixtures can occur below 150 K, with the main sulfur-containing product being bisulfate (HSO4(-)). Using a technique not previously applied to the low-temperature kinetics of either interstellar or solar system ice analogs, we estimate an activation energy of 32 kJ per mol for HSO4(-) formation. These results show that at the temperatures of the Jovian satellites, SO2 and O3 will efficiently react making detection of these molecules in the same vicinity unlikely. Our results also explain why O3 has not been detected on Callisto and why the SO2 concentration on Callisto appears to be highest on that world's leading hemisphere. Furthermore, our results predict that the SO2 concentration on Ganymede will be lowest in the trailing hemisphere, where the concentration of O3 is the highest. Our work suggests that thermal reactions in ices play a much more important role in surface and sub-surface chemistry than generally appreciated, possibly explaining the low abundance of sulfur-containing molecules and the lack of ozone observed in comets and interstellar ices.

  18. A simple differential steady-state method to measure the thermal conductivity of solid bulk materials with high accuracy.

    Science.gov (United States)

    Kraemer, D; Chen, G

    2014-02-01

    Accurate measurements of thermal conductivity are of great importance for materials research and development. Steady-state methods determine thermal conductivity directly from the proportionality between heat flow and an applied temperature difference (Fourier Law). Although theoretically simple, in practice, achieving high accuracies with steady-state methods is challenging and requires rather complex experimental setups due to temperature sensor uncertainties and parasitic heat loss. We developed a simple differential steady-state method in which the sample is mounted between an electric heater and a temperature-controlled heat sink. Our method calibrates for parasitic heat losses from the electric heater during the measurement by maintaining a constant heater temperature close to the environmental temperature while varying the heat sink temperature. This enables a large signal-to-noise ratio which permits accurate measurements of samples with small thermal conductance values without an additional heater calibration measurement or sophisticated heater guards to eliminate parasitic heater losses. Additionally, the differential nature of the method largely eliminates the uncertainties of the temperature sensors, permitting measurements with small temperature differences, which is advantageous for samples with high thermal conductance values and/or with strongly temperature-dependent thermal conductivities. In order to accelerate measurements of more than one sample, the proposed method allows for measuring several samples consecutively at each temperature measurement point without adding significant error. We demonstrate the method by performing thermal conductivity measurements on commercial bulk thermoelectric Bi2Te3 samples in the temperature range of 30-150 °C with an error below 3%.

  19. Development of a modular directional and spectral neutron detection system using solid-state detectors

    Energy Technology Data Exchange (ETDEWEB)

    Weltz, A., E-mail: weltza3@gmail.com; Torres, B.; McElwain, L.; Dahal, R.; Huang, J.; Bhat, I.; Lu, J.; Danon, Y.

    2015-08-21

    A detection system using room-temperature, microstructured solid-state thermal neutron detectors with very low leakage current has been developed at Rensselaer Polytechnic Institute (RPI) with the ability to provide positional and spectral information about an unknown neutron source. The Directional and Spectral Neutron Detection System (DSNDS) utilizes a set of small-but-scalable, zero-bias solid-state thermal neutron detectors which have demonstrated high thermal neutron efficiency and adequate gamma insensitivity. The DSNDS can gather spectral information about an unknown neutron source with a relatively small number of detectors, simplifying the detector electronics and minimizing cost; however, the DSNDS is modular in design, providing the capability to increase the detection efficiency and angular resolution. The system used in this paper was comprised of a stack of five high-density polyethylene (HDPE) disks with a thickness of 5 cm and a diameter of 30 cm, the middle disk containing 16 detectors positioned as one internal (moderated) and one external (unmoderated) ring of solid-state neutron detectors. These two detector rings provide the ability to determine the directionality of a neutron source. The system gathers spectral information about a neutron source in two ways: by measuring the relative responses of the internal ring of detectors as well as measuring the ratio of the internal-to-external detector responses. Experiments were performed with variable neutron spectra: a {sup 252}Cf spontaneous fission neutron source which was HDPE moderated, HDPE reflected, lead (Pb) shielded, and bare in order to benchmark the system for spectral sensitivity. Simulations were performed in order to characterize the neutron spectra corresponding to each of the source configurations and showed agreement with experimental measurements. The DSNDS demonstrates the ability to determine the relative angle of the source and the hardness of the neutron spectrum. By using the

  20. A stochastic model of solid state thin film deposition: Application to chalcopyrite growth

    Directory of Open Access Journals (Sweden)

    Robert J. Lovelett

    2016-04-01

    Full Text Available Developing high fidelity quantitative models of solid state reaction systems can be challenging, especially in deposition systems where, in addition to the multiple competing processes occurring simultaneously, the solid interacts with its atmosphere. In this work, we develop a model for the growth of a thin solid film where species from the atmosphere adsorb, diffuse, and react with the film. The model is mesoscale and describes an entire film with thickness on the order of microns. Because it is stochastic, the model allows us to examine inhomogeneities and agglomerations that would be impossible to characterize with deterministic methods. We demonstrate the modeling approach with the example of chalcopyrite Cu(InGa(SeS2 thin film growth via precursor reaction, which is a common industrial method for fabricating thin film photovoltaic modules. The model is used to understand how and why through-film variation in the composition of Cu(InGa(SeS2 thin films arises and persists. We believe that the model will be valuable as an effective quantitative description of many other materials systems used in semiconductors, energy storage, and other fast-growing industries.

  1. Silicon solid state devices and radiation detection

    CERN Document Server

    Leroy, Claude

    2012-01-01

    This book addresses the fundamental principles of interaction between radiation and matter, the principles of working and the operation of particle detectors based on silicon solid state devices. It covers a broad scope with respect to the fields of application of radiation detectors based on silicon solid state devices from low to high energy physics experiments including in outer space and in the medical environment. This book covers stateof- the-art detection techniques in the use of radiation detectors based on silicon solid state devices and their readout electronics, including the latest developments on pixelated silicon radiation detector and their application.

  2. Workshop Report: Fundamental Reactions in Solid Propellant Combustion

    Science.gov (United States)

    1979-05-01

    combustion conditions. 6. What effect might a pressure-induced phase transition to a polymorph other than 6- HMX have on the pressure slope break during...pure HMX as well. Nevertheless, it is recommended that the high pressure polymorphs of HMX and RDX be determined. It was also felt that there...plateau burning phenomena E. Solid phase, surface, gas phase reactions F. Phase transitions : melting, vaporization, polymorphs G. Flame

  3. Thermal stress management of a solid oxide fuel cell using neural network predictive control

    International Nuclear Information System (INIS)

    Hajimolana, S.A.; Tonekabonimoghadam, S.M.; Hussain, M.A.; Chakrabarti, M.H.; Jayakumar, N.S.; Hashim, M.A.

    2013-01-01

    In SOFC (solid oxide fuel cell) systems operating at high temperatures, temperature fluctuation induces a thermal stress in the electrodes and electrolyte ceramics; therefore, the cell temperature distribution is recommended to be kept as constant as possible. In the present work, a mathematical model based on first principles is presented to avert such temperature fluctuations. The fuel cell running on ammonia is divided into five subsystems and factors such as mass/energy/momentum transfer, diffusion through porous media, electrochemical reactions, and polarization losses inside the subsystems are presented. Dynamic cell-tube temperature responses of the cell to step changes in conditions of the feed streams is investigated. The results of simulation indicate that the transient response of the SOFC is mainly influenced by the temperature dynamics. It is also shown that the inlet stream temperatures are associated with the highest long term start-up time (467 s) among other parameters in terms of step changes. In contrast the step change in fuel velocity has the lowest influence on the start-up time (about 190 s from initial steady state to the new steady state) among other parameters. A NNPC (neural network predictive controller) is then implemented for thermal stress management by controlling the cell tube temperature to avoid performance degradation by manipulating the temperature of the inlet air stream. The regulatory performance of the NNPC is compared with a PI (proportional–integral) controller. The performance of the control system confirms that NNPC is a non-linear-model-based strategy which can assure less oscillating control responses with shorter settling times in comparison to the PI controller. - Highlights: • Effect of the operating parameters on the fuel cell temperature is analysed. • A neural network predictive controller (NNPC) is implemented. • The performance of NNPC is compared with the PI controller. • A detailed model is used for

  4. Thermal testing of solid neutron shielding materials

    International Nuclear Information System (INIS)

    Boonstra, R.H.

    1993-01-01

    In May-June 1989 the first series of full-scale thermal tests was performed on three shielding materials: Bisco Products NS-4-FR, and Reactor Experiments RX-201 and RX-207. The tests are described in Thermal Testing of Solid Neutron Shielding Materials, GA-A19897, R.H. Boonstra, General Atomics (1990), and demonstrated the acceptability of these materials in a thermal accident. Subsequent design changes to the cask rendered these materials unattractive in terms of weight or adequate service temperature margin. For the second test series a material specification was developed for a polypropylene based neutron shield with a softening point of at least 280degF. Table 1 lists the neutron shield materials tested. The Envirotech and Bisco materials are not polypropylene, but were tested as potential backup materials in the event that a satisfactory polypropylene could not be found. The Bisco modified NS-4 and Reactor Experiments HMPP are both acceptable materials from a thermal accident standpoint for use in the shipping cask. Tests of the Kobe PP-R01 and Envirotech HDPE were stopped for safety reasons, due to inability to deal with the heavy smoke, before completion of the 30-minute heating phase. However these materials may prove satisfactory if they could undergo the complete heating. (J.P.N.)

  5. THERMAL PROCESSING OF PHOSPHOGYPSUM WITH USING ENERGY OF INCINERATED SOLID HOUSEHOLD WASTE

    Directory of Open Access Journals (Sweden)

    KROT O. P.

    2017-05-01

    Full Text Available Summary. The use of resources that have not been directly used for their intended purpose is one of the important tasks of sustainable urban development. The need for an integrated approach to the problem of waste management is realized all over the world. In recent decades, there has been a trend in Ukraine for a significant increase in waste. European experience in handling solid domestic waste uses various processing methods: recycling on the basis of separate collection, sorting, composting and thermal processing with generation of thermal and electric energy. In Ukraine, the most common method of handling waste remains burial in landfills that do not meet European standards, are not properly equipped, they do not comply with the norms and rules of storage. This leads to contamination of groundwater, as well as to the release into the atmosphere of various compounds. No less problem is the accumulation of phosphogypsum in industrial waste dumps. It is necessary to develop innovative technology of a complex for utilization of phosphogypsum using thermal energy of solid domestic waste. The article compares the technological characteristics of aggregates for incineration of solid waste and the production of semi-aqua gypsum to identify the possibility of their interfacing, and also formulated tasks for eliminating inconsistencies in interfaced technologies. The equipment of thermal units of interfaced technologies is offered.

  6. Solid-state amorphization in the Ni-Zr system investigated by positron lifetime spectroscopy

    International Nuclear Information System (INIS)

    Bernal, M.J.; De La Cruz, R.M.; Leguey, T.; Pareja, R.; Riveiro, J.M.

    1995-01-01

    The process of mechanical alloying and amorphization of Ni-Zr powders is investigated by positron lifetime spectroscopy, X-ray diffraction and differential scanning calorimetry. The short-lived component of the lifetime spectra is composition and milling-time dependent. The second lifetime component, found during the initial stages of the milling process, appears to be due to annihilation from states trapped at crystalline interface joints. The results indicate that the solid-state reactions induced by ball milling involve the transformation and disappearance of the crystalline interface joints in the powder particles. (orig.)

  7. Optical and thermal energy discharge from tritiated solid hydrogen

    International Nuclear Information System (INIS)

    Magnotta, F.; Mapoles, E.R.; Collins, G.W.; Souers, P.C.

    1991-01-01

    The authors are investigating mechanisms of energy storage and release in tritiated solid hydrogens, by a variety of techniques including ESR, NMR and thermal and optical emission. The nuclear decay of a triton in solid hydrogen initiates the conversion of nuclear energy into stored chemical energy by producing unpaired hydrogen atoms which are trapped within the molecular lattice. The ability to store large quantities of atoms in this manner has been demonstrated and can serve as a basis for new forms of high energy density materials. This paper presents preliminary results of a study of the optical emission from solid hydrogen containing tritium over the visible and near infrared (NIR) spectral regions. Specifically, they have studied optical emission from DT and T 2 using CCD, silicon diode and germanium diode arrays. 8 refs., 6 figs

  8. Probe DNA-Cisplatin Interaction with Solid-State Nanopores

    Science.gov (United States)

    Zhou, Zhi; Hu, Ying; Li, Wei; Xu, Zhi; Wang, Pengye; Bai, Xuedong; Shan, Xinyan; Lu, Xinghua; Nanopore Collaboration

    2014-03-01

    Understanding the mechanism of DNA-cisplatin interaction is essential for clinical application and novel drug design. As an emerging single-molecule technology, solid-state nanopore has been employed in biomolecule detection and probing DNA-molecule interactions. Herein, we reported a real-time monitoring of DNA-cisplatin interaction by employing solid-state SiN nanopores. The DNA-cisplatin interacting process is clearly classified into three stages by measuring the capture rate of DNA-cisplatin adducts. In the first stage, the negative charged DNA molecules were partially discharged due to the bonding of positive charged cisplatin and forming of mono-adducts. In the second stage, forming of DNA-cisplatin di-adducts with the adjacent bases results in DNA bending and softening. The capture rate increases since the softened bi-adducts experience a lower barrier to thread into the nanopores. In the third stage, complex structures, such as micro-loop, are formed and the DNA-cisplatin adducts are aggregated. The capture rate decreases to zero as the aggregated adduct grows to the size of the pore. The characteristic time of this stage was found to be linear with the diameter of the nanopore and this dynamic process can be described with a second-order reaction model. We are grateful to Laboratory of Microfabrication, Dr. Y. Yao, and Prof. R.C. Yu (Institute of Physics, Chinese Academy of Sciences) for technical assistance.

  9. Solid state laser technology - A NASA perspective

    Science.gov (United States)

    Allario, F.

    1985-01-01

    NASA's program for developing solid-state laser technology and applying it to the Space Shuttle and Space Platform is discussed. Solid-state lasers are required to fulfill the Earth Observation System's requirements. The role of the Office of Aeronautics and Space Technology in developing a NASA tunable solid-state laser program is described. The major goals of the program involve developing a solid-state pump laser in the green, using AlGaAs array technology, pumping a Nd:YAG/SLAB crystal or glass, and fabricating a lidar system, with either a CO2 laser at 10.6 microns or a Nd:YAG laser at 1.06 microns, to measure tropospheric winds to an accuracy of + or - 1 m/s and a vertical resolution of 1 km. The procedures to be followed in order to visualize this technology plan include: (1) material development and characterization, (2) laser development, and (3) implementation of the lasers.

  10. Power and Thermal Technologies for Air and Space. Delivery Order 0001: Single Ionic Conducting Solid-State Electrolyte

    National Research Council Canada - National Science Library

    Turner, Allen

    2005-01-01

    This report focuses on the development of a lithium-ion conducting channel as a solid-state electrolyte for rechargeable lithium batteries through the use of thin films of dilithium phthalocyanine (Li2Pc...

  11. Low-Temperature Thermal Reactions Between SO2 and H2O2 and Their Relevance to the Jovian Icy Satellites

    Science.gov (United States)

    Loeffler, Mark J.; Hudson, Reggie L.

    2013-01-01

    Here we present first results on a non-radiolytic, thermally-driven reaction sequence in solid H2O +SO2 + H2O2 mixtures at 50-130 K, which produces sulfate (SO(-2)/(4)), and has an activation energy of 53 kJ/mole. We suspect that these results may explain some of the observations related to the presence and distribution of H2O2 across Europa's surface as well as the lack of H2O2 on Ganymede and Callisto.

  12. Chromium 51 em K2CrO4: reactions of dopant atoms in solid state

    International Nuclear Information System (INIS)

    Valim, J.B.; Nascimento, R.L.G. do; Collins, C.H.; Collins, K.E.

    1986-01-01

    The study of the chemistry of 'dopant' 51 Cr(III) atoms in crystalline Cr(VI) compounds began as a sub-field of Hot Atom Chemistry. We shall review the attempts to use 'dopant' chromium-51 atoms as surrogate chromium recoil atoms with the special property of having a low-energy, recoil-dam-age-free history. These dopant atoms have shown behaviors very similar to those of high energy recoil 51 Gr atoms, thus offering little hope of learning about special damage site structures and reactions by behavioral differences. Recent work has shown that at least some of the 'dopant' 51 Cr(III) is present as a second, non-chromate solid phase in 'doped crystal' experiments. Monodisperse 51 Cr(OH) 3 particles mixed with pure K 2 CrO 4 are very reactive. (Author) [pt

  13. Interference of the two spin components of the capture state in the (n, [gamma]) reaction

    NARCIS (Netherlands)

    Kamp, A.M.F. op den; Kopecky, J.; Stecher-Rasmussen, F.; Abrahams, K.; Endt, P.M.

    1972-01-01

    Measurements of the circularγ-ray polarization for primary transitions in the 39K(n, γ)40K and 57Fe(n, γ)58Fe reactions induced by thermal neutrons give strong evidence for the interference of components in the capture state with different J=values.

  14. Solid state track detectors

    International Nuclear Information System (INIS)

    Reuther, H.

    1976-11-01

    This paper gives a survey of the present state of the development and the application of solid state track detectors. The fundamentals of the physical and chemical processes of the track formation and development are explained, the different detector materials and their registration characteristics are mentioned, the possibilities of the experimental practice and the most variable applications are discussed. (author)

  15. Simulation of thermal stresses in anode-supported solid oxide fuel cell stacks. Part II: Loss of gas-tightness, electrical contact and thermal buckling

    Science.gov (United States)

    Nakajo, Arata; Wuillemin, Zacharie; Van herle, Jan; Favrat, Daniel

    Structural stability issues in planar solid oxide fuel cells arise from the mismatch between the coefficients of thermal expansion of the components. The stress state at operating temperature is the superposition of several contributions, which differ depending on the component. First, the cells accumulate residual stresses due to the sintering phase during the manufacturing process. Further, the load applied during assembly of the stack to ensure electric contact and flatten the cells prevents a completely stress-free expansion of each component during the heat-up. Finally, thermal gradients cause additional stresses in operation. The temperature profile generated by a thermo-electrochemical model implemented in an equation-oriented process modelling tool (gPROMS) was imported into finite-element software (ABAQUS) to calculate the distribution of stress and contact pressure on all components of a standard solid oxide fuel cell repeat unit. The different layers of the cell in exception of the cathode, i.e. anode, electrolyte and compensating layer were considered in the analysis to account for the cell curvature. Both steady-state and dynamic simulations were performed, with an emphasis on the cycling of the electrical load. The study includes two different types of cell, operation under both thermal partial oxidation and internal steam-methane reforming and two different initial thicknesses of the air and fuel compressive sealing gaskets. The results generated by the models are presented in two papers: Part I focuses on cell cracking. In the present paper, Part II, the occurrences of loss of gas-tightness in the compressive gaskets and/or electrical contact in the gas diffusion layer were identified. In addition, the dependence on temperature of both coefficients of thermal expansion and Young's modulus of the metallic interconnect (MIC) were implemented in the finite-element model to compute the plastic deformation, while the possibilities of thermal buckling

  16. Solid State Ionic Materials - Proceedings of the 4th Asian Conference on Solid State Ionics

    Science.gov (United States)

    Chowdari, B. V. R.; Yahaya, M.; Talib, I. A.; Salleh, M. M.

    1994-07-01

    SO4 (X=Si, Ge, Ti) Systems * A DSC and Conductivity Study of the Influence of Cesium Ion on the Beta-Alpha Transition in Silver Iodide * Phase Diagrams, Stoichiometries and Properties of Bi4V2O11:M2+ Solid Electrolytes * Physical Properties of Electrodeposited Silver Chromotungstate * Pseudopotential Study of Bonding in the Superionic Material AgI: The Effect of Statistical Distribution of Mobile Ions * Cubic Phase Dominant Region in Submicron BaTiO3 Particles * The Crystallization of CoZr Amorphous Alloys via Electrical Resistivity * Cation Ratio Related Properties of Synthetic Mg/Al Layered Double Hydroxide and it's Nanocomposite * DC Conductivity of Nano-Particles of Silver Iodide * Effect of Anomalous Diffusion on Quasielastic Scattering in Superionic Conductors * Computer Simulation Study of Conductivity Enhancement in Superionic-Insulator Composites * Dynamics of Superionic Silver and Copper Iodide Salt Melts * Influence of Dopant Salt AgI, Glass Modifier Ag2O and Glass Formers (SeO3 + MoO3) on Electrical Conductivity in Quaternary Glassy System * Fast Ion Conductivity in the Presence of Competitive Network Formers * Role of Alkali Ions in Borate Glasses * Inelastic Light Scattering in Cadmium Borate Glasses * Investigation on Transport Properties of Mixed Glass System 0.75 [0.75AgI:0.25AgCl]. 0.25[Ag2O:CrO3] * Conduction Mechanism in Lithium Tellurite Glasses * Optimized Silver Tungstoarsenate Glass Electrolyte * Stabilized Superfine Zirconia Powder Prepared by Sol-Gel Process * Study of New PAN-based Electrolytes * Electrical and Thermal Characterization of PVA based Polymer Electrolytes * Conductive Electroactive Polymers: Versatile Solid State Ionic Materials * The Role of Ag2O Addition on the Superconducting Properties of Y-124 Compound * Absorption Spectra Studies of the C60 Films on Transition Metal Film Substrates * Effect of Alumina Dispersal on the Conductivity and Crystallite Size of Polymer Electrolyte * New Mixed Galss-Polymer Solid Electrolytes

  17. Solid State Reactor Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mays, G.T.

    2004-03-10

    The Solid State Reactor (SSR) is an advanced reactor concept designed to take advantage of Oak Ridge National Laboratory's (ORNL's) recently developed graphite foam that has enhanced heat transfer characteristics and excellent high-temperature mechanical properties, to provide an inherently safe, self-regulated, source of heat for power and other potential applications. This work was funded by the U.S. Department of Energy's Nuclear Energy Research Initiative (NERI) program (Project No. 99-064) from August 1999 through September 30, 2002. The initial concept of utilizing the graphite foam as a basis for developing an advanced reactor concept envisioned that a suite of reactor configurations and power levels could be developed for several different applications. The initial focus was looking at the reactor as a heat source that was scalable, independent of any heat removal/power conversion process. These applications might include conventional power generation, isotope production and destruction (actinides), and hydrogen production. Having conducted the initial research on the graphite foam and having performed the scoping parametric analyses from neutronics and thermal-hydraulic perspectives, it was necessary to focus on a particular application that would (1) demonstrate the viability of the overall concept and (2) require a reasonably structured design analysis process that would synthesize those important parameters that influence the concept the most as part of a feasible, working reactor system. Thus, the application targeted for this concept was supplying power for remote/harsh environments and a design that was easily deployable, simplistic from an operational standpoint, and utilized the new graphite foam. Specifically, a 500-kW(t) reactor concept was pursued that is naturally load following, inherently safe, optimized via neutronic studies to achieve near-zero reactivity change with burnup, and proliferation resistant. These four major areas

  18. End-Member Formulation of Solid Solutions and Reactive Transport

    Energy Technology Data Exchange (ETDEWEB)

    Lichtner, Peter C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    A model for incorporating solid solutions into reactive transport equations is presented based on an end-member representation. Reactive transport equations are solved directly for the composition and bulk concentration of the solid solution. Reactions of a solid solution with an aqueous solution are formulated in terms of an overall stoichiometric reaction corresponding to a time-varying composition and exchange reactions, equivalent to reaction end-members. Reaction rates are treated kinetically using a transition state rate law for the overall reaction and a pseudo-kinetic rate law for exchange reactions. The composition of the solid solution at the onset of precipitation is assumed to correspond to the least soluble composition, equivalent to the composition at equilibrium. The stoichiometric saturation determines if the solid solution is super-saturated with respect to the aqueous solution. The method is implemented for a simple prototype batch reactor using Mathematica for a binary solid solution. Finally, the sensitivity of the results on the kinetic rate constant for a binary solid solution is investigated for reaction of an initially stoichiometric solid phase with an undersaturated aqueous solution.

  19. Monolithic solid-state lasers for spaceflight

    Science.gov (United States)

    Krainak, Michael A.; Yu, Anthony W.; Stephen, Mark A.; Merritt, Scott; Glebov, Leonid; Glebova, Larissa; Ryasnyanskiy, Aleksandr; Smirnov, Vadim; Mu, Xiaodong; Meissner, Stephanie; Meissner, Helmuth

    2015-02-01

    A new solution for building high power, solid state lasers for space flight is to fabricate the whole laser resonator in a single (monolithic) structure or alternatively to build a contiguous diffusion bonded or welded structure. Monolithic lasers provide numerous advantages for space flight solid-state lasers by minimizing misalignment concerns. The closed cavity is immune to contamination. The number of components is minimized thus increasing reliability. Bragg mirrors serve as the high reflector and output coupler thus minimizing optical coatings and coating damage. The Bragg mirrors also provide spectral and spatial mode selection for high fidelity. The monolithic structure allows short cavities resulting in short pulses. Passive saturable absorber Q-switches provide a soft aperture for spatial mode filtering and improved pointing stability. We will review our recent commercial and in-house developments toward fully monolithic solid-state lasers.

  20. 5V-class bulk-type all-solid-state rechargeable lithium batteries with electrode-solid electrolyte composite electrodes prepared by aerosol deposition

    Science.gov (United States)

    Iriyama, Yasutoshi; Wadaguchi, Masaki; Yoshida, Koki; Yamamoto, Yuta; Motoyama, Munekazu; Yamamoto, Takayuki

    2018-05-01

    Composite electrodes (∼9 μm in thickness) composed of 5V-class electrode of LiNi0.5Mn1.5O4 (LNM) and high Li+ conductive crystalline-glass solid electrolyte (LATP, Ohara Inc.) were prepared at room temperature by aerosol deposition (AD) on platinum sheets. The resultant LNM-LATP composite electrodes were combined with LiPON and Li, and 5V-class bulk-type all-solid-state rechargeable lithium batteries (SSBs) were prepared. The crystallnity of the LNM in the LNM-LATP composite electrode was improved by annealing. Both thermogravimetry-mass spectroscopy analysis and XRD analysis clarified that the side reactions between the LNM and the LATP occurred over 500 °C with oxygen release. From these results, annealing temperature of the LNM-LATP composite electrode system was optimized at 500 °C due to the improved crystallinity of the LNM with avoiding the side-reactions. The SSBs with the composite electrodes (9 μm in thickness, 40 vol% of the LNM) annealed at 500 °C delivered 100 mAh g-1 at 10 μA cm-2 at 100 °C. Degradation of the discharge capacity with the repetition of the charge-discharge reactions was observed, which will originate from large volume change of the LNM (∼6.5%) during the reactions.

  1. Mg-doped biphasic calcium phosphate by a solid state reaction route: Characterization and evaluation of cytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Webler, Geovana D. [Instituto de Física, Universidade Federal de Alagoas, Maceió-AL 57072970 (Brazil); Correia, Ana C.C.; Barreto, Emiliano [Laboratório de Biologia Celular, Universidade Federal de Alagoas, Maceió-AL 57072970 (Brazil); Fonseca, Eduardo J.S., E-mail: eduardo@fis.ufal.br [Instituto de Física, Universidade Federal de Alagoas, Maceió-AL 57072970 (Brazil)

    2015-07-15

    Hydroxyapatite (HAP) and β-tricalcium phosphate (β-TCP) are widely used in tissue engineering because of their chemical similarity to the inorganic bone phase. In this work, we prepare biphasic calcium phosphate (BCP, a mixture of HAP and β-TCP) doped with different concentrations of magnesium to investigate the influence of magnesium on the BCP crystal structure. Magnesium is known to be an important element in the composition of bones and teeth. Recent research has shown that the doping of magnesium into BCP improves its bone metabolism and mechanical properties without affecting its biocompatibility. The samples were prepared by solid-state reaction from calcium carbonate, monobasic ammonium phosphate, and magnesium nitrate hexahydrate. Varying concentrations of magnesium were used and its modifications were examined by different characterization techniques. The phase composition and morphology of the ceramic powders were characterized by X-ray diffraction and scanning electron microscopy, respectively. The functional groups were analyzed using Fourier transform infrared spectroscopy and Raman spectroscopy. Cell viability experiments, using macrophage-like cell lines J774, showed that the synthesized Mg-doped BCP did not exhibit cytotoxicity regardless of the doses assayed or the different concentrations of magnesium used, suggesting it as a good material for potential biological applications. - Highlights: • Simple and fast method for the preparation of the Mg-BCP. • Study of the influence of the incorporation of Mg in the BCP. • Cell viability showed that the synthesized Mg-BCP did not exhibit cytotoxicity.

  2. Mg-doped biphasic calcium phosphate by a solid state reaction route: Characterization and evaluation of cytotoxicity

    International Nuclear Information System (INIS)

    Webler, Geovana D.; Correia, Ana C.C.; Barreto, Emiliano; Fonseca, Eduardo J.S.

    2015-01-01

    Hydroxyapatite (HAP) and β-tricalcium phosphate (β-TCP) are widely used in tissue engineering because of their chemical similarity to the inorganic bone phase. In this work, we prepare biphasic calcium phosphate (BCP, a mixture of HAP and β-TCP) doped with different concentrations of magnesium to investigate the influence of magnesium on the BCP crystal structure. Magnesium is known to be an important element in the composition of bones and teeth. Recent research has shown that the doping of magnesium into BCP improves its bone metabolism and mechanical properties without affecting its biocompatibility. The samples were prepared by solid-state reaction from calcium carbonate, monobasic ammonium phosphate, and magnesium nitrate hexahydrate. Varying concentrations of magnesium were used and its modifications were examined by different characterization techniques. The phase composition and morphology of the ceramic powders were characterized by X-ray diffraction and scanning electron microscopy, respectively. The functional groups were analyzed using Fourier transform infrared spectroscopy and Raman spectroscopy. Cell viability experiments, using macrophage-like cell lines J774, showed that the synthesized Mg-doped BCP did not exhibit cytotoxicity regardless of the doses assayed or the different concentrations of magnesium used, suggesting it as a good material for potential biological applications. - Highlights: • Simple and fast method for the preparation of the Mg-BCP. • Study of the influence of the incorporation of Mg in the BCP. • Cell viability showed that the synthesized Mg-BCP did not exhibit cytotoxicity

  3. Synchrotron radiation in solid state chemistry

    International Nuclear Information System (INIS)

    Ghigna, Paolo; Pin, Sonia; Spinolo, Giorgio; Newton, Mark A.; Chiara Tarantino, Serena; Zema, Michele

    2011-01-01

    An approach towards the reactivity in the solid state is proposed, primarily based on recognizing the crucial role played by the interfacial free energy and by the topotactical relationship between the two reactants, which in turn control formation of the new phase and its spatial and orientational relationships with respect to the parent phases. Using one of the reactants in the form of film, the ratio between bulk and interfacial free energy can be changed, and the effect of interfacial free energy is maximized. The role of Synchrotron Radiation in such an approach is exemplified by using a new developed technique for μ-XANES mapping with nanometric resolution for studying the reactivity of thin films of NiO onto differently oriented Al 2 O 3 single crystals. The result obtained allowed us to speculate about the rate determining step of the NiO+Al 2 O 3 →NiAl 2 O 4 interfacial reaction.

  4. A novel steam explosion sterilization improving solid-state fermentation performance.

    Science.gov (United States)

    Zhao, Zhi-Min; Wang, Lan; Chen, Hong-Zhang

    2015-09-01

    Traditional sterilization of solid medium (SM) requires lengthy time, degrades nutrients, and even sterilizes inadequately compared with that of liquid medium due to its low thermal conductivity. A novel sterilization strategy, high-temperature and short-time steam explosion (SE), was exploited for SM sterilization in this study. Results showed that SE conditions for complete sterilization were 172 °C for 2 min and 128 °C for 5 min. Glucose and xylose contents in medium after SE sterilization increased by 157% and 93% respectively compared with those after conventional sterilization (121 °C, 20 min) while fermentation inhibitors were not detected. FTIR spectra revealed that the mild SE conditions helped to release monosaccharides from the polysaccharides. Bacillus subtilis fermentation productivity on medium after SE sterilization was 3.83 times of that after conventional sterilization. Therefore, SE shortened sterilization time and improved SM nutrition, which facilitated fermentability of SM and should promote economy of solid-state fermentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Solid state physics

    CERN Document Server

    Grosso, Giuseppe

    2013-01-01

    Solid State Physics is a textbook for students of physics, material science, chemistry, and engineering. It is the state-of-the-art presentation of the theoretical foundations and application of the quantum structure of matter and materials. This second edition provides timely coverage of the most important scientific breakthroughs of the last decade (especially in low-dimensional systems and quantum transport). It helps build readers' understanding of the newest advances in condensed matter physics with rigorous yet clear mathematics. Examples are an integral part of the text, carefully de

  6. Annual report of the Tandem Accelerator Center, Nuclear and Solid State Research Project, University of Tsukuba

    International Nuclear Information System (INIS)

    1981-01-01

    During the academic year 1980 - 1981, the 12 UD Pelletron tandem accelerator in UTTAC has experienced several troubles. The accelerator tank had to be opened six times including the scheduled overhaul. Due to these troubles, both the beam time and the chain operation time were reduced by 20% as compared with the preceding year. However, the beam pulsing system was completed, and pulsed beam has been in use. The polarized ion source and the sputter ion source have worked well. A heavy ion booster with interdigital H-structure was designed, and has been under construction. Special efforts have been exerted on the detectors and detector systems. The examples of the achievements mainly associated with the Nuclear and Solid State Research Project are enumerated as follows. The complete experiment on d-p system provided the data on nuclear three body problem. The information about the mechanism of two-nucleon transfer reaction (p,t) was obtained. The mechanisms of (p,p) and (p,d) reactions were clarified. The experiment on the measurement of the magnetic moment of β-emitting products with polarized beam began. The properties of very highly excited states were clarified by the study of heavy ion-induced reactions. A new model for heavy ion fusion reaction was proposed. The mechanism of inner shell ionization was clarified by passing heavy ions through solids. (Kako, I.)

  7. Phosphorescent and thermoluminescent properties of SrAl2O4:Eu2+, Dy3+ phosphors prepared by solid state reaction method

    International Nuclear Information System (INIS)

    Mothudi, B.M.; Ntwaeaborwa, O.M.; Kumar, A.; Sohn, K.; Swart, H.C.

    2012-01-01

    Long persistent SrAl 2 O 4 :Eu 2+ phosphors co-doped with Dy 3+ were prepared by the solid state reaction method. The main diffraction peaks of the monoclinic structure of SrAl 2 O 4 were observed in all the samples. The broad band emission spectra at 497 nm for SrAl 2 O 4 :Eu 2+ , Dy 3+ were observed and the emission is attributed to the 4f 6 5d 1 to 4f 7 transition of Eu 2+ ions. The samples annealed at 1100–1200 °C showed similar broad TL glow curves centered at 120 °C. The similar TL glow curves suggest that the traps responsible for them are similar. The long afterglow displayed by the phosphors annealed at different temperatures, may be attributed to the Dy 3+ ions acting as the hole trap levels, which play an important role in prolonging the duration of luminescence.

  8. On the thermalization achieved in the reactions involving superheavy nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, Rajni [Department of Physics, MCM DAV College for Women, Sector 36A, Chandigarh-160036, India rajnibansal.pu@gmail.com (India)

    2016-05-06

    In the present study, we aim to explore the role of Coulomb potential on the thermalization achieved in the reactions involving superheavy nuclei. Particularly, we shall study the degree of the equilibrium attained in a reaction by the 3D density plots, anisotropy ratio as well as by the rapidity distribution of the nucleons. Our study reveals that the degree of the equilibrium attained in the central reactions of the superheavy nuclei remains unaffected by the Coulomb potential.

  9. High energy bursts from a solid state laser operated in the heat capacity limited regime

    Science.gov (United States)

    Albrecht, G.; George, E.V.; Krupke, W.F.; Sooy, W.; Sutton, S.B.

    1996-06-11

    High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes. 5 figs.

  10. Effects on nuclear fusion reaction on diffusion and thermal conduction in a magnetoplasma

    International Nuclear Information System (INIS)

    Sakai, Kazuo; Aono, Osamu.

    1976-12-01

    In spite of the well spread belief in the field of irreversible thermodynamics, vectorial phenomena couple thermodynamically with the scalar phenomena. Transport coefficients concerning the diffusion and the thermal conduction across a strong magnetic field are calculated in the presence of the deuteron-triton fusion reaction on the basis of the gas kinetic theory. When the reaction takes place, the diffusion increases and the thermal conduction decreases. Effects of the reaction exceed those of the Coulomb collision as the temperature is high enough. (auth.)

  11. Form-stable paraffin/high density polyethylene composites as solid-liquid phase change material for thermal energy storage: preparation and thermal properties

    International Nuclear Information System (INIS)

    Sari, Ahmet

    2004-01-01

    This paper deals with the preparation of paraffin/high density polyethylene (HDPE) composites as form-stable, solid-liquid phase change material (PCM) for thermal energy storage and with determination of their thermal properties. In such a composite, the paraffin (P) serves as a latent heat storage material and the HDPE acts as a supporting material, which prevents leakage of the melted paraffin because of providing structural strength. Therefore, it is named form-stable composite PCM. In this study, two kinds of paraffins with melting temperatures of 42-44 deg. C (type P1) and 56-58 deg. C (type P2) and latent heats of 192.8 and 212.4 J g -1 were used. The maximum weight percentage for both paraffin types in the PCM composites without any seepage of the paraffin in the melted state were found as high as 77%. It is observed that the paraffin is dispersed into the network of the solid HDPE by investigation of the structure of the composite PCMs using a scanning electronic microscope (SEM). The melting temperatures and latent heats of the form-stable P1/HDPE and P2/HDPE composite PCMs were determined as 37.8 and 55.7 deg. C, and 147.6 and 162.2 J g -1 , respectively, by the technique of differential scanning calorimetry (DSC). Furthermore, to improve the thermal conductivity of the form-stable P/HDPE composite PCMs, expanded and exfoliated graphite (EG) by heat treatment was added to the samples in the ratio of 3 wt.%. Thereby, the thermal conductivity was increased about 14% for the form-stable P1/HDPE and about 24% for the P2/HDPE composite PCMs. Based on the results, it is concluded that the prepared form-stable P/HDPE blends as composite type PCM have great potential for thermal energy storage applications in terms of their satisfactory thermal properties and improved thermal conductivity. Furthermore, these composite PCMs added with EG can be considered cost effective latent heat storage materials since they do not require encapsulation and extra cost to enhance

  12. SOLID-STATE STORAGE DEVICE FLASH TRANSLATION LAYER

    DEFF Research Database (Denmark)

    2017-01-01

    Embodiments of the present invention include a method for storing a data page d on a solid-state storage device, wherein the solid-state storage device is configured to maintain a mapping table in a Log-Structure Merge (LSM) tree having a C0 component which is a random access memory (RAM) device...

  13. Distribution and Thermal Maturity of Devonian Carbonate Reservoir Solid Bitumen in Desheng Area of Guizhong Depression, South China

    Directory of Open Access Journals (Sweden)

    Yuguang Hou

    2017-01-01

    Full Text Available The distribution of solid bitumen in the Devonian carbonate reservoir from well Desheng 1, Guizhong Depression, was investigated by optical microscope and hydrocarbon inclusions analysis. Vb and chemical structure indexes measured by bitumen reflectance, laser Raman microprobe (LRM, and Fourier transform infrared spectroscopy (FTIR were carried out to determine the thermal maturity of solid bitumen. Based on the solid bitumen thermal maturity, the burial and thermal maturity history of Devonian carbonate reservoir were reconstructed by basin modeling. The results indicate that the fractures and fracture-related dissolution pores are the main storage space for the solid bitumen. The equivalent vitrinite reflectance of solid bitumen ranges from 3.42% to 4.43% converted by Vb (% and LRM. The infrared spectroscopy analysis suggests that there are no aliphatic chains detected in the solid bitumen which is rich in aromatics C=C chains (1431–1440 cm−1. The results of Vb (%, LRM, and FTIR analysis demonstrate that the solid bitumen has experienced high temperature and evolved to the residual carbonaceous stage. The thermal evolution of Devonian reservoirs had experienced four stages. The Devonian reservoirs reached the highest reservoir temperature 210–260°C during the second rapid burial-warming stage, which is the main period for the solid bitumen formation.

  14. Modeling thermal spike driven reactions at low temperature and application to zirconium carbide radiation damage

    Science.gov (United States)

    Ulmer, Christopher J.; Motta, Arthur T.

    2017-11-01

    The development of TEM-visible damage in materials under irradiation at cryogenic temperatures cannot be explained using classical rate theory modeling with thermally activated reactions since at low temperatures thermal reaction rates are too low. Although point defect mobility approaches zero at low temperature, the thermal spikes induced by displacement cascades enable some atom mobility as it cools. In this work a model is developed to calculate "athermal" reaction rates from the atomic mobility within the irradiation-induced thermal spikes, including both displacement cascades and electronic stopping. The athermal reaction rates are added to a simple rate theory cluster dynamics model to allow for the simulation of microstructure evolution during irradiation at cryogenic temperatures. The rate theory model is applied to in-situ irradiation of ZrC and compares well at cryogenic temperatures. The results show that the addition of the thermal spike model makes it possible to rationalize microstructure evolution in the low temperature regime.

  15. The Design, Synthesis, and Study of Solid-State Molecular Rotors: Structure/Function Relationships for Condensed-Phase Anisotropic Dynamics

    Science.gov (United States)

    Vogelsberg, Cortnie Sue

    strong to direct an assembly of molecular machines, 3) the relative flexibility of the crystal environment proximate to a dynamic component may have a significant effect on its function, and, 4) molecular machines, which possess both solid-state photochemical reactivity and dynamics may show complex reaction kinetics if the correlation time of the dynamic process and the lifetime of the excited state occur on the same time scale and the dynamic moiety inherently participates as a reaction intermediate. The study of periodic mesoporous organosilica with hierarchical order probed molecular dynamics within 2D layers of molecular rotors, organized in only one dimension and with ca. 50% exposed to the mesopore free volume. From their study, it was discovered that: 1) molecular rotors, which comprise the layers of the mesopore walls, form a 2D rotational glass, 2) rotator dynamics within the 2D rotational glass undergo a transition to a 2D rotational fluid, and, 3) a 2D rotational glass transition may be exploited to develop hyper-sensitive thermally activated molecular machines. The study of a metal-organic framework assembled from molecular rotors probed dynamics in a periodic three-dimensional free-volume environment, without the presence of close contacts. From the study of this solid-state material, it was determined that: 1) the intrinsic electronic barrier is one of the few factors, which may affect functional dynamics in a true free-volume environment, and, 2) molecular machines with dynamic barriers <

  16. KfK, Institute for Nuclear Solid-State Physics. Report of results on research and development work 1985

    International Nuclear Information System (INIS)

    1986-02-01

    The Institute for Nuclear Solid-State Physics pursues at time mainly basis-oriented work in the fields of superconductivity and the boundary-surface and microstructure research. The experimental and theoretical works aim to a better understanding of the microscopical and macroscopical properties of certain solids. At time superconductors with high transition point, highly correlated electron systems, conducting polymers, and amorphous substances are studied especially intensively. Technologically relevant materials have in the comparative case preference. Beside the experimental methods of nuclear solid-state physics (neutron scattering, Moessbauer spectroscopy, ion-implantation technology, irradiation and analysis with fast ions) the institute disposes of further highly specificated techniques, like electron-energy-loss-spectroscopy, special material preparation, X-ray diffractometry, and two UHV facilities for the study of the first surface respectively near-surface regions with thermal helium atoms as well as with fast ions. (orig./HSI) [de

  17. optimisation of solid optimisation of solid state fermentation

    African Journals Online (AJOL)

    eobe

    from banana peels via solid state fermentation using Aspergillus niger. ermentation ... [7,8], apple pomace [9], banana peels [4], date palm. [10], carob ... powder, jams, juice, bar, biscuits, wine etc results in ... Yeast extract was taken as nitrogen.

  18. Defect engineering: design tools for solid state electrochemical devices

    International Nuclear Information System (INIS)

    Tuller, Harry L.

    2003-01-01

    The interest in solid state electrochemical devices including sensors, fuel cells, batteries, oxygen permeation membranes, etc. has grown rapidly in recent years. Many of the same figures of merit apply to these different applications, the key ones being ionic conduction in solid electrolytes, mixed ionic-electronic conduction (MIEC) in electrodes and permeation membranes, and gas-solid reaction kinetics in sensors and fuel cells. Optimization of device performance often relies on the careful understanding and control of both ionic and electronic defects in the materials that make up the key device components. To date, most materials in use have been discovered serendipitously. A key focus of this paper is on the tools available to scientists and engineers to practice 'defect engineering' for the purpose of optimizing the performance of such materials. Dopants, controlled structural disorder, and interfaces are examined in relation to increasing the conductivity of solid electrolytes. The creation of defect bands is demonstrated as a means for introducing high levels of electronic conductivity into a solid electrolyte for the purpose of creating a mixed conductor and thereby a monolithic fuel cell structure. Dopants are also examined as a means of reducing losses in a high temperature resonant sensor platform. The control of microstructure, down to the nano-scale, is shown capable of inverting the predominant ionic to an electronic charge carrier and thereby markedly modifying electrical properties. Electrochemical bias and light are also discussed in terms of creating defects locally thereby providing means for micromachining a broad range of materials with precise dimensional control, low residual stress and controlled etch rates

  19. Solid state electrolytes for all-solid-state 3D lithium-ion batteries

    NARCIS (Netherlands)

    Kokal, I.

    2012-01-01

    The focus of this Ph.D. thesis is to understand the lithium ion motion and to enhance the Li-ionic conductivities in commonly known solid state lithium ion conductors by changing the structural properties and preparation methods. In addition, the feasibility for practical utilization of several

  20. Studies on spectroscopic and thermal behaviour of neodymium soaps

    International Nuclear Information System (INIS)

    Mehrotra, K.N.; Chauhan, M.; Shukla, R.K.

    1992-01-01

    The present work has been initiated with a view to study the nature of bonding, structure, thermal and micellar behaviour of neodymium soaps in non-aqueous media. The structure of these soaps in solid state has been investigated by infrared spectra and X-ray diffraction patterns, and spectrophotometric result confirms the nature of bonding and micellar behaviour of neodymium soaps. The results of TGA have been used to explain the order of reaction and to find out the values of energy of activation for the decomposition process. (author). 9 refs., 5 tabs

  1. Theoretical study on thermal stability of molten salt for solar thermal power

    International Nuclear Information System (INIS)

    Wei, Xiaolan; Peng, Qiang; Ding, Jing; Yang, Xiaoxi; Yang, Jianping; Long, Bin

    2013-01-01

    Molten salt (HTS) composed of 53% KNO 3 , 40% NaNO 2 and 7 wt.% NaNO 3 has been used as heat transfer media and thermal storage fluid in the solar thermal power, but thermal decomposition will occur at higher temperature because of the oxidation of nitrite to nitrate in the air. In this paper, the reaction mechanism of NO 2 − oxidation is researched by quantum mechanical method. The results show that two components of the transition state (O 2 NO 2 − ) and intermediate ([NO 4 − ]) are found in the reaction. This reaction is an exothermic reaction and the activation barrier is 94.0 kJ mol −1 . The energy difference of this reaction is very large, so the reaction rate is very slow. -- Highlights: ► The mechanism of the oxidation of nitrite salt in HTS is explained. ► Two components of the transition state (O 2 NO 2 − ) and intermediate ([NO 4 − ]) are found. ► The activation barrier of the nitrite oxidation is determined

  2. Thermal transformations of oxohalide complexes of rhenium(5) and molybdenum(5) with diazo-18-crown-6 in solid phase

    International Nuclear Information System (INIS)

    Ashurova, N.Kh.; Yakubov, K.G.

    1992-01-01

    Methods for synthesis and separation in solid state of the rhenium(5) and molybdenum(5) onium complexes with diaza-18-crown-6(L), the content of which according to the data of elementary analysis, IRS in the close and remote areas, thermogravimetry, conductometry and potentiometry corresponds to the (H 2 L)[EOX 5 ], where E = Re, Mo; X = Cl - , Br - . Thermotransformation of onium compounds is studied by methods of thermal methods (TG-DTG-DTA combined study). Their avility to be affected by solid-phase dehydrohalogenization, e.i. anderson regrouping. The thermolysis products, corresponding to the general formula (EOLX 3 ), are separated and studied

  3. Mathematical model to analyze the dissolution behavior of metastable crystals or amorphous drug accompanied with a solid-liquid interface reaction.

    Science.gov (United States)

    Hirai, Daiki; Iwao, Yasunori; Kimura, Shin-Ichiro; Noguchi, Shuji; Itai, Shigeru

    2017-04-30

    Metastable crystals and the amorphous state of poorly water-soluble drugs in solid dispersions (SDs), are subject to a solid-liquid interface reaction upon exposure to a solvent. The dissolution behavior during the solid-liquid interface reaction often shows that the concentration of drugs is supersaturated, with a high initial drug concentration compared with the solubility of stable crystals but finally approaching the latter solubility with time. However, a method for measuring the precipitation rate of stable crystals and/or the potential solubility of metastable crystals or amorphous drugs has not been established. In this study, a novel mathematical model that can represent the dissolution behavior of the solid-liquid interface reaction for metastable crystals or amorphous drug was developed and its validity was evaluated. The theory for this model was based on the Noyes-Whitney equation and assumes that the precipitation of stable crystals at the solid-liquid interface occurs through a first-order reaction. Moreover, two models were developed, one assuming that the surface area of the drug remains constant because of the presence of excess drug in the bulk and the other that the surface area changes in time-dependency because of agglomeration of the drug. SDs of Ibuprofen (IB)/polyvinylpyrrolidone (PVP) were prepared and their dissolution behaviors under non-sink conditions were fitted by the models to evaluate improvements in solubility. The model assuming time-dependent surface area showed good agreement with experimental values. Furthermore, by applying the model to the dissolution profile, parameters such as the precipitation rate and the potential solubility of the amorphous drug were successfully calculated. In addition, it was shown that the improvement in solubility with supersaturation was able to be evaluated quantitatively using this model. Therefore, this mathematical model would be a useful tool to quantitatively determine the supersaturation

  4. Comparisons of predicted steady-state levels in rooms with extended- and local-reaction bounding surfaces

    Science.gov (United States)

    Hodgson, Murray; Wareing, Andrew

    2008-01-01

    A combined beam-tracing and transfer-matrix model for predicting steady-state sound-pressure levels in rooms with multilayer bounding surfaces was used to compare the effect of extended- and local-reaction surfaces, and the accuracy of the local-reaction approximation. Three rooms—an office, a corridor and a workshop—with one or more multilayer test surfaces were considered. The test surfaces were a single-glass panel, a double-drywall panel, a carpeted floor, a suspended-acoustical ceiling, a double-steel panel, and glass fibre on a hard backing. Each test surface was modeled as of extended or of local reaction. Sound-pressure levels were predicted and compared to determine the significance of the surface-reaction assumption. The main conclusions were that the difference between modeling a room surface as of extended or of local reaction is not significant when the surface is a single plate or a single layer of material (solid or porous) with a hard backing. The difference is significant when the surface consists of multilayers of solid or porous material and includes a layer of fluid with a large thickness relative to the other layers. The results are partially explained by considering the surface-reflection coefficients at the first-reflection angles.

  5. Passivation-free solid state battery

    Science.gov (United States)

    Abraham, Kuzhikalail M.; Peramunage, Dharmasena

    1998-01-01

    This invention pertains to passivation-free solid-state rechargeable batteries composed of Li.sub.4 Ti.sub.5 O.sub.12 anode, a solid polymer electrolyte and a high voltage cathode. The solid polymer electrolyte comprises a polymer host, such as polyacrylonitrile, poly(vinyl chloride), poly(vinyl sulfone), and poly(vinylidene fluoride), plasticized by a solution of a Li salt in an organic solvent. The high voltage cathode includes LiMn.sub.2 O.sub.4, LiCoO.sub.2, LiNiO.sub.2 and LiV.sub.2 O.sub.5 and their derivatives.

  6. The Oxford solid state basics

    CERN Document Server

    Simon, Steven H

    2013-01-01

    The study of solids is one of the richest, most exciting, and most successful branches of physics. While the subject of solid state physics is often viewed as dry and tedious this new book presents the topic instead as an exciting exposition of fundamental principles and great intellectual breakthroughs. Beginning with a discussion of how the study of heat capacity of solids ushered in the quantum revolution, the author presents the key ideas of the field while emphasizing the deepunderlying concepts. The book begins with a discussion of the Einstein/Debye model of specific heat, and the Drude

  7. Level crossing analysis of chemically induced dynamic nuclear polarization: Towards a common description of liquid-state and solid-state cases

    Energy Technology Data Exchange (ETDEWEB)

    Sosnovsky, Denis V.; Ivanov, Konstantin L., E-mail: ivanov@tomo.nsc.ru [International Tomography Centre of SB RAS, Institutskaya 3a, 630090, Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova 2, 630090, Novosibirsk (Russian Federation); Jeschke, Gunnar [Institut für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland); Matysik, Jörg [Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, D-04103 Leipzig (Germany); Vieth, Hans-Martin [International Tomography Centre of SB RAS, Institutskaya 3a, 630090, Novosibirsk (Russian Federation); Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin (Germany)

    2016-04-14

    Chemically Induced Dynamic Nuclear Polarization (CIDNP) is an efficient method of creating non-equilibrium polarization of nuclear spins by using chemical reactions, which have radical pairs as intermediates. The CIDNP effect originates from (i) electron spin-selective recombination of radical pairs and (ii) the dependence of the inter-system crossing rate in radical pairs on the state of magnetic nuclei. The CIDNP effect can be investigated by using Nuclear Magnetic Resonance (NMR) methods. The gain from CIDNP is then two-fold: it allows one to obtain considerable amplification of NMR signals; in addition, it provides a very useful tool for investigating elusive radicals and radical pairs. While the mechanisms of the CIDNP effect in liquids are well established and understood, detailed analysis of solid-state CIDNP mechanisms still remains challenging; likewise a common theoretical frame for the description of CIDNP in both solids and liquids is missing. Difficulties in understanding the spin dynamics that lead to the CIDNP effect in the solid-state case are caused by the anisotropy of spin interactions, which increase the complexity of spin evolution. In this work, we propose to analyze CIDNP in terms of level crossing phenomena, namely, to attribute features in the CIDNP magnetic field dependence to Level Crossings (LCs) and Level Anti-Crossings (LACs) in a radical pair. This approach allows one to describe liquid-state CIDNP; the same holds for the solid-state case where anisotropic interactions play a significant role in CIDNP formation. In solids, features arise predominantly from LACs, since in most cases anisotropic couplings result in perturbations, which turn LCs into LACs. We have interpreted the CIDNP mechanisms in terms of the LC/LAC concept. This consideration allows one to find analytical expressions for a wide magnetic field range, where several different mechanisms are operative; furthermore, the LAC description gives a way to determine CIDNP sign

  8. Solid-state ring laser gyroscope

    Science.gov (United States)

    Schwartz, S.

    The ring laser gyroscope is a rotation sensor used in most kinds of inertial navigation units. It usually consists in a ring cavity filled with a mixture of helium and neon, together with high-voltage pumping electrodes. The use of a gaseous gain medium, while resulting naturally in a stable bidirectional regime enabling rotation sensing, is however the main industrially limiting factor for the ring laser gyroscopes in terms of cost, reliability and lifetime. We study in this book the possibility of substituting for the gaseous gain medium a solid-state medium (diode-pumped Nd-YAG). For this, a theoretical and experimental overview of the lasing regimes of the solid-state ring laser is reported. We show that the bidirectional emission can be obtained thanks to a feedback loop acting on the states of polarization and inducing differential losses proportional to the difference of intensity between the counterpropagating modes. This leads to the achievement of a solid-state ring laser gyroscope, whose frequency response is modified by mode coupling effects. Several configurations, either mechanically or optically based, are then successively studied, with a view to improving the quality of this frequency response. In particular, vibration of the gain crystal along the longitudinal axis appears to be a very promising technique for reaching high inertial performances with a solid-state ring laser gyroscope. Gyrolaser à état solide. Le gyrolaser est un capteur de rotation utilisé dans la plupart des centrales de navigation inertielle. Dans sa forme usuelle, il est constitué d'une cavité laser en anneau remplie d'un mélange d'hélium et de néon pompé par des électrodes à haute tension. L'utilisation d'un milieu amplificateur gazeux, si elle permet de garantir naturellement le fonctionnement bidirectionnel stable nécessaire à la mesure des rotations, constitue en revanche la principale limitation industrielle des gyrolasers actuels en termes de coût, fiabilit

  9. Thermal conductivity of solid cyclohexane in orientationally ordered and disordered phases

    International Nuclear Information System (INIS)

    Konstantinov, V. A.; Revyakin, V. P.; Sagan, V. V.; Pursky, O. I.; Sysoev, V. M.

    2011-01-01

    Thermal conductivity Λ P of solid cyclohexane is measured at a pressure P = 0.1 MPa in the temperature range from 80 K to the melting point, which covers the ranges of low-temperature orientationally ordered phase II and high-temperature orientationally disordered phase I. Thermal conductivity Λ V is measured at a constant volume in orientationally disordered phase I. The thermal conductivity measured at atmospheric pressure decreases with increasing temperature as Λ P ∝ T −1.15 in phase II, whereas Λ P ∝ T −0.3 in phase I. As temperature increases, isochoric thermal conductivity Λ V in phase I increases gradually. The experimental data are described in terms of a modified Debye model of thermal conductivity with allowance for heat transfer by both phonons and “diffuse” modes.

  10. Solid-state dynamics and single-crystal to single-crystal structural transformations in octakis(3-chloropropyl)octasilsesquioxane and octavinyloctasilsesquioxane.

    Science.gov (United States)

    Kowalewska, A; Nowacka, M; Włodarska, M; Zgardzińska, B; Zaleski, R; Oszajca, M; Krajenta, J; Kaźmierski, S

    2017-10-18

    Reactive octahedral silsesquioxanes of rod-like [octakis(3-chloropropyl)octasilsesquioxane - T 8 (CH 2 CH 2 CH 2 Cl) 8 ] and spherical [octavinyloctasilsesquioxane - T 8 (CH[double bond, length as m-dash]CH 2 ) 8 ] structure can undergo reversible thermally induced phase transitions in the solid state. The phase behaviour has been studied with differential scanning calorimetry (DSC, including temperature modulated DSC), X-ray diffraction, dielectric relaxation spectroscopy (DRS), and nuclear magnetic resonance spectroscopy in the solid state (SS NMR), as well as positron annihilation lifetime spectroscopy (PALS) and polarized optical microscopy (POM). The mechanisms involving fitting the molecules into most symmetrical crystal lattices vary for species of different structure. Thermal energy can be used to expand the crystal lattice leading to thermochromism in the case of T 8 (CH[double bond, length as m-dash]CH 2 ) 8 or conversely to an unusual negative thermal expansion of crystals of T 8 (CH 2 CH 2 CH 2 Cl) 8 that results in their self-actuation. The complex behaviour is reflected in unusual changes in the capacitance and fractional free volume of the material. These phenomena can be used for molecular design of advanced well-defined hybrid materials capable of reversible thermally induced structural transformations. The findings present a new perspective for POSS-based flexible metal-organic frameworks (MOF) of cooperative structural transformability via entropy-based translational sub-net sliding.

  11. High-average-power solid state lasers

    International Nuclear Information System (INIS)

    Summers, M.A.

    1989-01-01

    In 1987, a broad-based, aggressive R ampersand D program aimed at developing the technologies necessary to make possible the use of solid state lasers that are capable of delivering medium- to high-average power in new and demanding applications. Efforts were focused along the following major lines: development of laser and nonlinear optical materials, and of coatings for parasitic suppression and evanescent wave control; development of computational design tools; verification of computational models on thoroughly instrumented test beds; and applications of selected aspects of this technology to specific missions. In the laser materials areas, efforts were directed towards producing strong, low-loss laser glasses and large, high quality garnet crystals. The crystal program consisted of computational and experimental efforts aimed at understanding the physics, thermodynamics, and chemistry of large garnet crystal growth. The laser experimental efforts were directed at understanding thermally induced wave front aberrations in zig-zag slabs, understanding fluid mechanics, heat transfer, and optical interactions in gas-cooled slabs, and conducting critical test-bed experiments with various electro-optic switch geometries. 113 refs., 99 figs., 18 tabs

  12. Effect of Grinding on the Solid-State Stability and Particle Dissolution of Acyclovir Polymorphs.

    Science.gov (United States)

    Magnoni, Federico; Gigliobianco, Maria Rosa; Vargas Peregrina, Dolores; Censi, Roberta; Di Martino, Piera

    2017-10-01

    The present work investigated the solid state change of 4 acyclovir polymorphs when ground at room temperature (Method A) and under cryo-grinding in the presence of liquid nitrogen (Method B). Modifications in particle size and shape (evaluated by scanning electron microscopy) and in the water content (evaluated by thermal analysis) were related to transitions at the solid state, as confirmed by X-ray powder diffractometry. Anhydrous Form I was stable under grinding by both Methods A and B. The anhydrous Form II was stable during grinding under Method A, whereas it was progressively converted to the hydrate Form V during grinding under Method B. The hydrate Form V was stable under Method A, whereas it was converted to the anhydrous Form I after 15 min and then to the hydrate Form VI after 45 min of grinding. The hydrate Form VI proved to be stable under grinding by both Methods A and B. Thus, Form I and VI were the only forms that yielded a sizeable decrease in particle size under grinding, with a consequent increase in particle dissolution rate, while maintaining solid state physicochemical stability. Form I treated under Method B grinding gave the best dissolution rate. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  13. Repercussion of Solid state vs. Liquid state synthesized p-n heterojunction RGO-copper phosphate on proton reduction potential in water.

    Science.gov (United States)

    Samal, Alaka; Das, Dipti P; Madras, Giridhar

    2018-02-13

    The same copper phosphate catalysts were synthesized by obtaining the methods involving solid state as well as liquid state reactions in this work. And then the optimised p-n hybrid junction photocatalysts have been synthesized following the same solid/liquid reaction pathways. The synthesized copper phosphate photocatalyst has unique rod, flower, caramel-treat-like morphology. The Mott-Schottky behavior is in accordance with the expected behavior of n-type semiconductor and the carrier concentration was calculated using the M-S analysis for the photocatalyst. And for the p-n hybrid junction of 8RGO-Cu 3 (PO 4 ) 2 -PA (PA abbreviated for photoassisted synthesis method), 8RGO-Cu 3 (PO 4 ) 2 -EG(EG abbreviated for Ethylene Glycol based synthesis method), 8RGO-Cu 3 (PO 4 ) 2 -PEG (PEG abbreviated for Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol based synthesis method)the amount of H 2 synthesized was 7500, 6500 and 4500 µmol/h/g, respectively. The excited electrons resulting after the irradiation of visible light on the CB of p-type reduced graphene oxide (RGO) migrate easily to n-type Cu 3 (PO 4 ) 2 via. the p-n junction interfaces and hence great charge carrier separation was achieved.

  14. An introduction to solid state diffusion

    CERN Document Server

    Borg, Richard J

    2012-01-01

    The energetics and mechanisms of diffusion control the kinetics of such diverse phenomena as the fabrication of semiconductors and superconductors, the tempering of steel, geological metamorphism, the precipitation hardening of nonferrous alloys and corrosion of metals and alloys. This work explains the fundamentals of diffusion in the solid state at a level suitable for upper-level undergraduate and beginning graduate students in materials science, metallurgy, mineralogy, and solid state physics and chemistry. A knowledge of physical chemistry such as is generally provided by a one-year under

  15. Design and fabrication of a novel self-powered solid-state neutron detector

    Science.gov (United States)

    LiCausi, Nicholas

    There is a strong interest in intercepting special nuclear materials (SNM) at national and international borders and ports for homeland security applications. Detection of SNM such as U and Pu is often accomplished by sensing their natural or induced neutron emission. Such detector systems typically use thermal neutron detectors inside a plastic moderator. In order to achieve high detection efficiency gas filled detectors are often used; these detectors require high voltage bias for operation, which complicates the system when tens or hundreds of detectors are deployed. A better type of detector would be an inexpensive solid-state detector that can be mass-produced like any other computer chip. Research surrounding solid-state detectors has been underway since the late 1990's. A simple solid-state detector employs a planar solar-cell type p-n junction and a thin conversion material that converts incident thermal neutrons into detectable alpha-particles and 7Li ions. Existing work has typically used 6LiF or 10B as this conversion layer. Although a simple planar detector can act as a highly portable, low cost detector, it is limited to relatively low detection efficiency (˜10%). To increase the efficiency, 3D perforated p-i-n silicon devices were proposed. To get high efficiency, these detectors need to be biased, resulting in increased leakage current and hence detector noise. In this research, a new type of detector structure was proposed, designed and fabricated. Among several detector structures evaluated, a honeycomb-like silicon p-n structure was selected, which is filled with natural boron as the neutron converter. A silicon p+-n diode formed on the thin silicon wall of the honeycomb structure detects the energetic alpha-particles emitted from the boron conversion layer. The silicon detection layer is fabricated to be fully depleted with an integral step during the boron filling process. This novel feature results in a simplified fabrication process. Three

  16. Chemical and nanometer-scale structure of kerogen and its change during thermal maturation investigated by advanced solid-state 13C NMR spectroscopy

    Science.gov (United States)

    Mao, J.; Fang, X.; Lan, Y.; Schimmelmann, A.; Mastalerz, Maria; Xu, L.; Schmidt-Rohr, K.

    2010-01-01

    We have used advanced and quantitative solid-state nuclear magnetic resonance (NMR) techniques to investigate structural changes in a series of type II kerogen samples from the New Albany Shale across a range of maturity (vitrinite reflectance R0 from 0.29% to 1.27%). Specific functional groups such as CH3, CH2, alkyl CH, aromatic CH, aromatic C-O, and other nonprotonated aromatics, as well as "oil prone" and "gas prone" carbons, have been quantified by 13C NMR; atomic H/C and O/C ratios calculated from the NMR data agree with elemental analysis. Relationships between NMR structural parameters and vitrinite reflectance, a proxy for thermal maturity, were evaluated. The aromatic cluster size is probed in terms of the fraction of aromatic carbons that are protonated (???30%) and the average distance of aromatic C from the nearest protons in long-range H-C dephasing, both of which do not increase much with maturation, in spite of a great increase in aromaticity. The aromatic clusters in the most mature sample consist of ???30 carbons, and of ???20 carbons in the least mature samples. Proof of many links between alkyl chains and aromatic rings is provided by short-range and long-range 1H-13C correlation NMR. The alkyl segments provide most H in the samples; even at a carbon aromaticity of 83%, the fraction of aromatic H is only 38%. While aromaticity increases with thermal maturity, most other NMR structural parameters, including the aromatic C-O fractions, decrease. Aromaticity is confirmed as an excellent NMR structural parameter for assessing thermal maturity. In this series of samples, thermal maturation mostly increases aromaticity by reducing the length of the alkyl chains attached to the aromatic cores, not by pronounced growth of the size of the fused aromatic ring clusters. ?? 2010 Elsevier Ltd. All rights reserved.

  17. In-situ investigation of thermal instabilities and solid state dewetting in polycrystalline platinum thin films via confocal laser microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jahangir, S.; Cheng, Xuan; Huang, H. H.; Nagarajan, V. [School of Materials Science and Engineering, University of New South Wales, Sydney 2052 (Australia); Ihlefeld, J. [Electronic, Optical, and Nanomaterials Department, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    2014-10-28

    Solid state dewetting and the subsequent morphological changes for platinum thin films grown on zinc oxide (ZnO) buffered (001) silicon substrates (Pt/ZnO/SiO{sub 2}/(001)Si system) is investigated under vacuum conditions via a custom-designed confocal laser microscope coupled with a laser heating system. Live imaging of thin film dewetting under a range of heating and quenching vacuum ambients reveals events including hillock formation, hole formation, and hole growth that lead to formation of a network of Pt ligaments, break up of Pt ligaments to individual islands and subsequent Pt islands shape reformation, in chronological fashion. These findings are corroborated by ex-situ materials characterization and quantitative electron microscopy analysis. A secondary hole formation via blistering before film rupture is revealed to be the critical stage, after which a rapid dewetting catastrophe occurs. This process is instantaneous and cannot be captured by ex-situ methods. Finally, an intermetallic phase forms at 900 °C and alters the morphology of Pt islands, suggesting a practical limit to the thermal environments that may be used for these platinized silicon wafers in vacuum conditions.

  18. In-situ investigation of thermal instabilities and solid state dewetting in polycrystalline platinum thin films via confocal laser microscopy

    International Nuclear Information System (INIS)

    Jahangir, S.; Cheng, Xuan; Huang, H. H.; Nagarajan, V.; Ihlefeld, J.

    2014-01-01

    Solid state dewetting and the subsequent morphological changes for platinum thin films grown on zinc oxide (ZnO) buffered (001) silicon substrates (Pt/ZnO/SiO 2 /(001)Si system) is investigated under vacuum conditions via a custom-designed confocal laser microscope coupled with a laser heating system. Live imaging of thin film dewetting under a range of heating and quenching vacuum ambients reveals events including hillock formation, hole formation, and hole growth that lead to formation of a network of Pt ligaments, break up of Pt ligaments to individual islands and subsequent Pt islands shape reformation, in chronological fashion. These findings are corroborated by ex-situ materials characterization and quantitative electron microscopy analysis. A secondary hole formation via blistering before film rupture is revealed to be the critical stage, after which a rapid dewetting catastrophe occurs. This process is instantaneous and cannot be captured by ex-situ methods. Finally, an intermetallic phase forms at 900 °C and alters the morphology of Pt islands, suggesting a practical limit to the thermal environments that may be used for these platinized silicon wafers in vacuum conditions.

  19. Controllable synthesis of a monophase nickel phosphide/carbon (Ni{sub 5}P{sub 4}/C) composite electrode via wet-chemistry and a solid-state reaction for the anode in lithium secondary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yi; Tu, Jiang-Ping; Xiong, Qin-Qin; Mai, Yong-Jin; Zhang, Jun; Qiao, Yan-Qiang; Wang, Xiu-Li; Gu, Chang-Dong [State Key Laboratory of Silicon Materials and Department of Materials, Science and Engineering, Zhejiang University, Hangzhou, 310027 (China); Xiang, Jia-Yuan [Narada Power Source Co. Ltd., Hangzhou, 311105 (China); Mao, Scott X. [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA 15261 (United States)

    2012-09-25

    A monophase nickel phosphide/carbon (Ni{sub 5}P{sub 4}/C) composite with a thin carbon shell is controllably synthesized via the two-step strategy of a wet-chemistry reaction and a solid-state reaction. In this fabrication, the further diffusion of phosphorus atoms in the carbon shell during the solid-state reaction can be responsible for a chemical transformation from a binary phase of Ni{sub 5}P{sub 4}-Ni{sub 2}P to monophase Ni{sub 5}P{sub 4}. Galvanostatic charge-discharge measurements indicate that the Ni{sub 5}P{sub 4}/C composite exhibits a superior, high rate capacity and good cycling stability. About 76.6% of the second capacity (644.1 mA h g{sup -1}) can be retained after 50 cycles at a 0.1 C rate. At a high rate of 3 C, the specific capacity of Ni{sub 5}P{sub 4}/C is still as high as 357.1 mA h g{sup -1}. Importantly, the amorphous carbon shell can enhance the conductivity of the composite and suppress the aggregation of the active particles, leading to their structure stability and reversibility during cycling. As is confirmed from X-ray-diffraction analysis, no evident microstructural changes occur upon cycling. These results reveal that highly crystalline Ni{sub 5}P{sub 4}/C is one of the most promising anode materials for lithium-ion batteries. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. 3D-Printing Electrolytes for Solid-State Batteries.

    Science.gov (United States)

    McOwen, Dennis W; Xu, Shaomao; Gong, Yunhui; Wen, Yang; Godbey, Griffin L; Gritton, Jack E; Hamann, Tanner R; Dai, Jiaqi; Hitz, Gregory T; Hu, Liangbing; Wachsman, Eric D

    2018-05-01

    Solid-state batteries have many enticing advantages in terms of safety and stability, but the solid electrolytes upon which these batteries are based typically lead to high cell resistance. Both components of the resistance (interfacial, due to poor contact with electrolytes, and bulk, due to a thick electrolyte) are a result of the rudimentary manufacturing capabilities that exist for solid-state electrolytes. In general, solid electrolytes are studied as flat pellets with planar interfaces, which minimizes interfacial contact area. Here, multiple ink formulations are developed that enable 3D printing of unique solid electrolyte microstructures with varying properties. These inks are used to 3D-print a variety of patterns, which are then sintered to reveal thin, nonplanar, intricate architectures composed only of Li 7 La 3 Zr 2 O 12 solid electrolyte. Using these 3D-printing ink formulations to further study and optimize electrolyte structure could lead to solid-state batteries with dramatically lower full cell resistance and higher energy and power density. In addition, the reported ink compositions could be used as a model recipe for other solid electrolyte or ceramic inks, perhaps enabling 3D printing in related fields. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.