Sample records for conventional solid state

  1. An extrapolation scheme for solid-state NMR chemical shift calculations

    NASA Astrophysics Data System (ADS)

    Nakajima, Takahito

    2017-06-01

    Conventional quantum chemical and solid-state physical approaches include several problems to accurately calculate solid-state nuclear magnetic resonance (NMR) properties. We propose a reliable computational scheme for solid-state NMR chemical shifts using an extrapolation scheme that retains the advantages of these approaches but reduces their disadvantages. Our scheme can satisfactorily yield solid-state NMR magnetic shielding constants. The estimated values have only a small dependence on the low-level density functional theory calculation with the extrapolation scheme. Thus, our approach is efficient because the rough calculation can be performed in the extrapolation scheme.

  2. Nonthermal effects in photostimulated solid state reaction of Mn doped SrTiO3

    NASA Astrophysics Data System (ADS)

    Daraselia, D.; Japaridze, D.; Jibuti, Z.; Shengelaya, A.; Müller, K. A.

    2017-04-01

    The effect of a photostimulated solid state reaction was investigated in Mn doped SrTiO3 samples. Light irradiation was performed by either halogen or UV lamps in order to study the effect of the spectral composition, and the results were compared with samples prepared at the same temperatures in a conventional furnace. The obtained samples were studied by X-ray diffraction for structural characterization and by Electron Paramagnetic Resonance, which provides microscopic information about the local environment as well as the valence state of Mn ions. It was found that light irradiation significantly enhances the solid state reaction rate compared to synthesis in the conventional furnace. Moreover, it was observed that UV lamp irradiation is much more effective compared to halogen lamps. This indicates that the absorption of light with energy larger than the materials band gap plays an important role and points towards the nonthermal mechanism of the photostimulated solid state reaction.

  3. Review—Practical Challenges Hindering the Development of Solid State Li Ion Batteries

    DOE PAGES

    Kerman, Kian; Luntz, Alan; Viswanathan, Venkatasubramanian; ...

    2017-06-09

    Solid state electrolyte systems boasting Li+ conductivity of >10 mS cm -1 at room temperature have opened the potential for developing a solid state battery with power and energy densities that are competitive with conventional liquid electrolyte systems. The primary focus of this review is twofold. First, differences in Li penetration resistance in solid state systems are discussed, and kinetic limitations of the solid state interface are highlighted. Second, technological challenges associated with processing such systems in relevant form factors are elucidated, and architectures needed for cell level devices in the context of product development are reviewed. Specific research vectorsmore » that provide high value to advancing solid state batteries are outlined and discussed.« less

  4. A review of lithium and non-lithium based solid state batteries

    NASA Astrophysics Data System (ADS)

    Kim, Joo Gon; Son, Byungrak; Mukherjee, Santanu; Schuppert, Nicholas; Bates, Alex; Kwon, Osung; Choi, Moon Jong; Chung, Hyun Yeol; Park, Sam

    2015-05-01

    Conventional lithium-ion liquid-electrolyte batteries are widely used in portable electronic equipment such as laptop computers, cell phones, and electric vehicles; however, they have several drawbacks, including expensive sealing agents and inherent hazards of fire and leakages. All solid state batteries utilize solid state electrolytes to overcome the safety issues of liquid electrolytes. Drawbacks for all-solid state lithium-ion batteries include high resistance at ambient temperatures and design intricacies. This paper is a comprehensive review of all aspects of solid state batteries: their design, the materials used, and a detailed literature review of various important advances made in research. The paper exhaustively studies lithium based solid state batteries, as they are the most prevalent, but also considers non-lithium based systems. Non-lithium based solid state batteries are attaining widespread commercial applications, as are also lithium based polymeric solid state electrolytes. Tabular representations and schematic diagrams are provided to underscore the unique characteristics of solid state batteries and their capacity to occupy a niche in the alternative energy sector.

  5. Method and apparatus for semi-solid material processing

    DOEpatents

    Han, Qingyou [Knoxville, TN; Jian, Xiaogang [Knoxville, TN; Xu, Hanbing [Knoxville, TN; Meek, Thomas T [Knoxville, TN

    2009-02-24

    A method of forming a material includes the steps of: vibrating a molten material at an ultrasonic frequency while cooling the material to a semi-solid state to form non-dendritic grains therein; forming the semi-solid material into a desired shape; and cooling the material to a solid state. The method makes semi-solid castings directly from molten materials (usually a metal), produces grain size usually in the range of smaller than 50 .mu.m, and can be easily retrofitted into existing conventional forming machine.

  6. Method and apparatus for semi-solid material processing

    DOEpatents

    Han, Qingyou [Knoxville, TN; Jian, Xiaogang [Knoxville, TN; Xu, Hanbing [Knoxville, TN; Meek, Thomas T [Knoxville, TN

    2009-11-24

    A method of forming a material includes the steps of: vibrating a molten material at an ultrasonic frequency while cooling the material to a semi-solid state to form non-dendritic grains therein; forming the semi-solid material into a desired shape; and cooling the material to a solid state. The method makes semi-solid castings directly from molten materials (usually a metal), produces grain size usually in the range of smaller than 50 .mu.m, and can be easily retrofitted into existing conventional forming maching.

  7. Method and apparatus for semi-solid material processing

    DOEpatents

    Han, Qingyou [Knoxville, TN; Jian, Xiaogang [Knoxville, TN; Xu, Hanbing [Knoxville, TN; Meek, Thomas T [Knoxville, TN

    2007-05-15

    A method of forming a material includes the steps of: vibrating a molten material at an ultrasonic frequency while cooling the material to a semi-solid state to form non-dendritic grains therein; forming the semi-solid material into a desired shape; and cooling the material to a solid state. The method makes semi-solid castings directly from molten materials (usually a metal), produces grain size usually in the range of smaller than 50 .mu.m, and can be easily retrofitted into existing conventional forming machine.

  8. Fundamental characteristics of degradation-recoverable solid-state DFB polymer laser.

    PubMed

    Yoshioka, Hiroaki; Yang, Yu; Watanabe, Hirofumi; Oki, Yuji

    2012-02-13

    A novel solid-state dye laser with degradation recovery was proposed and demonstrated. Polydimethylsiloxane was used as a nanoporous solid matrix to enable the internal circulation of dye molecules in the solid state. An internal circulation model for the dye molecules was also proposed and verified numerically by assuming molecular mobility and using a proposed diffusion equation. The durability of the laser was increased 20.5-fold compared with that of a conventional polymethylmethacrylate laser. This novel laser solves the low-durability problem of dye-doped polymer lasers.

  9. The Operating Principle of a Fully Solid State Active Magnetic Regenerator

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abdelaziz, Omar

    As an alternative refrigeration technology, magnetocaloric refrigeration has the potential to be safer, quieter, more efficient, and more environmentally friendly than the conventional vapor compression refrigeration technology. Most of the reported active magnetic regenerator (AMR) systems that operate based on the magnetocaloric effect use heat transfer fluid to exchange heat, which results in complicated mechanical subsystems and components such as rotating valves and hydraulic pumps. This paper presents an operating principle of a fully solid state AMR, in which an alternative mechanism for heat transfer between the AMR and the heat source/sink is proposed. The operating principle of the fullymore » solid state AMR is based on moving rods/sheets (e.g. copper, brass, iron or aluminum), which are employed to replace the heat transfer fluid. Such fully solid state AMR would provide a significantly higher heat transfer rate than a conventional AMR because the conductivity of moving solid rods/plates is high and it enables the increase in the machine operating frequency hence the cooling capacity. The details of operating principle are presented and discussed here. One of the key enabling features for this technology is the contact between the moving rods/sheets and magnetocaloric material, and heat exchange mechanism at the heat source/sink. This paper provides an overview of the design for a fully solid state magnetocaloric refrigeration system along with guidelines for their optimal design.« less

  10. Solid-state NMR imaging system

    DOEpatents

    Gopalsami, Nachappa; Dieckman, Stephen L.; Ellingson, William A.

    1992-01-01

    An apparatus for use with a solid-state NMR spectrometer includes a special imaging probe with linear, high-field strength gradient fields and high-power broadband RF coils using a back projection method for data acquisition and image reconstruction, and a real-time pulse programmer adaptable for use by a conventional computer for complex high speed pulse sequences.

  11. Solar power satellite system definition study. Volume 4: Solid State SPS Analysis, Phase 3

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A 2500 megawatt solid ground output Solar Power Satellite (SPS) of conventional configuration was designed and analyzed. Because the power per receiving antenna is halved, as compared with the klystron reference, twice the number of receiving antennas are needed to deliver the same total power. The solid state approach appears feasible with a slightly greater specific mass and slightly higher cost than the klystron SPS design.

  12. Emulating short-term synaptic dynamics with memristive devices

    NASA Astrophysics Data System (ADS)

    Berdan, Radu; Vasilaki, Eleni; Khiat, Ali; Indiveri, Giacomo; Serb, Alexandru; Prodromakis, Themistoklis

    2016-01-01

    Neuromorphic architectures offer great promise for achieving computation capacities beyond conventional Von Neumann machines. The essential elements for achieving this vision are highly scalable synaptic mimics that do not undermine biological fidelity. Here we demonstrate that single solid-state TiO2 memristors can exhibit non-associative plasticity phenomena observed in biological synapses, supported by their metastable memory state transition properties. We show that, contrary to conventional uses of solid-state memory, the existence of rate-limiting volatility is a key feature for capturing short-term synaptic dynamics. We also show how the temporal dynamics of our prototypes can be exploited to implement spatio-temporal computation, demonstrating the memristors full potential for building biophysically realistic neural processing systems.

  13. Combinatorial synthesis of phosphors using arc-imaging furnace

    PubMed Central

    Ishigaki, Tadashi; Toda, Kenji; Yoshimura, Masahiro; Uematsu, Kazuyoshi; Sato, Mineo

    2011-01-01

    We have applied a novel ‘melt synthesis technique’ rather than a conventional solid-state reaction to rapidly synthesize phosphor materials. During a synthesis, the mixture of oxides or their precursors is melted by light pulses (10–60 s) in an arc-imaging furnace on a water-cooled copper hearth to form a globule of 1–5 mm diameter, which is then rapidly cooled by turning off the light. Using this method, we synthesized several phosphor compounds including Y3Al5O12:Ce(YAG) and SrAl2O4:Eu,Dy. Complex phosphor oxides are difficult to produce by conventional solid-state reaction techniques because of the slow reaction rates among solid oxides; as a result, the oxides form homogeneous compounds or solid solutions. On the other hand, melt reactions are very fast (10–60 s) and result in homogeneous compounds owing to rapid diffusion and mixing in the liquid phase. Therefore, melt synthesis techniques are suitable for preparing multi component homogeneous compounds and solid solutions. PMID:27877432

  14. Combinatorial synthesis of phosphors using arc-imaging furnace

    NASA Astrophysics Data System (ADS)

    Ishigaki, Tadashi; Toda, Kenji; Yoshimura, Masahiro; Uematsu, Kazuyoshi; Sato, Mineo

    2011-10-01

    We have applied a novel 'melt synthesis technique' rather than a conventional solid-state reaction to rapidly synthesize phosphor materials. During a synthesis, the mixture of oxides or their precursors is melted by light pulses (10-60 s) in an arc-imaging furnace on a water-cooled copper hearth to form a globule of 1-5 mm diameter, which is then rapidly cooled by turning off the light. Using this method, we synthesized several phosphor compounds including Y3Al5O12:Ce(YAG) and SrAl2O4:Eu,Dy. Complex phosphor oxides are difficult to produce by conventional solid-state reaction techniques because of the slow reaction rates among solid oxides; as a result, the oxides form homogeneous compounds or solid solutions. On the other hand, melt reactions are very fast (10-60 s) and result in homogeneous compounds owing to rapid diffusion and mixing in the liquid phase. Therefore, melt synthesis techniques are suitable for preparing multi component homogeneous compounds and solid solutions.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kozawa, Takahiro, E-mail: t-kozawa@jwri.osaka-u.ac.jp; Yanagisawa, Kazumichi; Murakami, Takeshi

    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 particlesmore » 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.« less

  16. Realisation of an all solid state lithium battery using solid high temperature plastic crystal electrolytes exhibiting liquid like conductivity.

    PubMed

    Shekibi, Youssof; Rüther, Thomas; Huang, Junhua; Hollenkamp, Anthony F

    2012-04-07

    Replacement of volatile and combustible electrolytes in conventional lithium batteries is desirable for two reasons: safety concerns and increase in specific energy. In this work we consider the use of an ionic organic plastic crystal material (IOPC), N-ethyl-N-methylpyrrolidinium tetrafluoroborate, [C2mpyr][BF(4)], as a solid-state electrolyte for lithium battery applications. The effect of inclusion of 1 to 33 mol% lithium tetrafluoroborate, LiBF(4), into [C2mpyr][BF(4)] has been investigated over a wide temperature range by differential scanning calorimetry (DSC), impedance spectroscopy, cyclic voltammetry and cycling of full Li|LiFePO(4) batteries. The increases in ionic conductivity by orders of magnitude observed at higher temperature are most likely associated with an increase in Li ion mobility in the highest plastic phase. At concentrations >5 mol% LiBF(4) the ionic conductivity of these solid-state composites is comparable to the ionic conductivity of room temperature ionic liquids. Galvanostatic cycling of Li|Li symmetrical cells showed that the reversibility of the lithium metal redox reaction at the interface of this plastic crystal electrolyte is sufficient for lithium battery applications. For the first time we demonstrate an all solid state lithium battery incorporating solid electrolytes based on IOPC as opposed to conventional flammable organic solvents.

  17. Microwave Crystallization of Lithium Aluminum Germanium Phosphate Solid-State Electrolyte.

    PubMed

    Mahmoud, Morsi M; Cui, Yuantao; Rohde, Magnus; Ziebert, Carlos; Link, Guido; Seifert, Hans Juergen

    2016-06-23

    Lithium aluminum germanium phosphate (LAGP) glass-ceramics are considered as promising solid-state electrolytes for Li-ion batteries. LAGP glass was prepared via the regular conventional melt-quenching method. Thermal, chemical analyses and X-ray diffraction (XRD) were performed to characterize the prepared glass. The crystallization of the prepared LAGP glass was done using conventional heating and high frequency microwave (MW) processing. Thirty GHz microwave (MW) processing setup were used to convert the prepared LAGP glass into glass-ceramics and compared with the conventionally crystallized LAGP glass-ceramics that were heat-treated in an electric conventional furnace. The ionic conductivities of the LAGP samples obtained from the two different routes were measured using impedance spectroscopy. These samples were also characterized using XRD and scanning electron microscopy (SEM). Microwave processing was successfully used to crystallize LAGP glass into glass-ceramic without the aid of susceptors. The MW treated sample showed higher total, grains and grain boundary ionic conductivities values, lower activation energy and relatively larger-grained microstructure with less porosity compared to the corresponding conventionally treated sample at the same optimized heat-treatment conditions. The enhanced total, grains and grain boundary ionic conductivities values along with the reduced activation energy that were observed in the MW treated sample was considered as an experimental evidence for the existence of the microwave effect in LAGP crystallization process. MW processing is a promising candidate technology for the production of solid-state electrolytes for Li-ion battery.

  18. Investigation of Super Tube Structure and Performance (Postprint)

    DTIC Science & Technology

    2010-04-01

    thermosyphon is claimed as thermally superconductive and offers solid state mode of heat transport. A host of speculations about this claim was emerging...sealed structure and design of a conventional heat pipe or thermosyphon is claimed as thermally superconductive and offers solid state mode of heat...matrix. The tilt angle was varied to check for gravity dependence. Tests were run as step functions allowing the tube to reach steady state at a new

  19. Solid-state 27Al MRI and NMR thermometry for catalytic applications with conventional (liquids) MRI instrumentation and techniques.

    PubMed

    Koptyug, Igor V; Sagdeev, Dmitry R; Gerkema, Edo; Van As, Henk; Sagdeev, Renad Z

    2005-07-01

    Multidimensional images of Al2O3 pellets, cordierite monolith, glass tube, polycrystalline V2O5 and other materials have been detected by 27Al, 51V, and 23Na NMR imaging using techniques and instrumentation conventionally employed for imaging of liquids. These results demonstrate that, contrary to the widely accepted opinion, imaging of "rigid" solids does not necessarily require utilization of solid state NMR imaging approaches, pulse sequences and hardware even for quadrupolar nuclei which exhibit line widths in excess of 100 kHz, such as 51V in polycrystalline V2O5. It is further demonstrated that both 27Al NMR signal intensity and spin-lattice relaxation time decrease with increasing temperature and thus can potentially serve as temperature sensitive parameters for spatially resolved NMR thermometry.

  20. A self-forming composite electrolyte for solid-state sodium battery with ultra-long cycle life

    DOE PAGES

    Zhang, Zhizhen; Yang, Xiao -Qing; Zhang, Qinghua; ...

    2016-10-31

    Replacing organic liquid electrolyte with inorganic solid electrolytes (SE) can potentially address the inherent safety problems in conventional rechargeable batteries. Furthermore, all-solid-state batteries have been plagues by the relatively low ionic conductivity of solid electrolytes and large charge-transfer resistance resulted from solid-solid interfaces between electrode materials and solid electrolytes. Here we report a new design strategy for improving the ionic conductivity of solid electrolyte by self-forming a composite material. An optimized Na + ion conducting composite electrolyte derived from the NASICON structure was successfully synthesized, yielding ultra-high ionic conductivity of 3.4 mS cm –1 at 25°C and 14 ms cmmore » –1 at 80°C.« less

  1. 15N and 31P solid-state NMR study of transmembrane domain alignment of M2 protein of influenza A virus in hydrated cylindrical lipid bilayers confined to anodic aluminum oxide nanopores.

    PubMed

    Chekmenev, Eduard Y; Hu, Jun; Gor'kov, Peter L; Brey, William W; Cross, Timothy A; Ruuge, Andres; Smirnov, Alex I

    2005-04-01

    This communication reports the first example of a high resolution solid-state 15N 2D PISEMA NMR spectrum of a transmembrane peptide aligned using hydrated cylindrical lipid bilayers formed inside nanoporous anodic aluminum oxide (AAO) substrates. The transmembrane domain SSDPLVVA(A-15N)SIIGILHLILWILDRL of M2 protein from influenza A virus was reconstituted in hydrated 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine bilayers that were macroscopically aligned by a conventional micro slide glass support or by the AAO nanoporous substrate. 15N and 31P NMR spectra demonstrate that both the phospholipids and the protein transmembrane domain are uniformly aligned in the nanopores. Importantly, nanoporous AAO substrates may offer several advantages for membrane protein alignment in solid-state NMR studies compared to conventional methods. Specifically, higher thermal conductivity of aluminum oxide is expected to suppress thermal gradients associated with inhomogeneous radio frequency heating. Another important advantage of the nanoporous AAO substrate is its excellent accessibility to the bilayer surface for exposure to solute molecules. Such high accessibility achieved through the substrate nanochannel network could facilitate a wide range of structure-function studies of membrane proteins by solid-state NMR.

  2. Flexible solid-state symmetric supercapacitors based on MnO2 nanofilms with high rate capability and long cyclability

    NASA Astrophysics Data System (ADS)

    Wu, Lingxia; Li, Ruizhi; Guo, Junling; Zhou, Cheng; Zhang, Wenpei; Wang, Chong; Huang, Yu; Li, Yuanyuan; Liu, Jinping

    2013-08-01

    Flexible solid-state symmetric supercapacitor was fabricated using MnO2 nanofilms growing directly on carbon cloth as the electrodes and PVA/H3PO4 gel as the electrolyte/separator. The device can be operated at a stable cell-voltage up to 1.4 V, obviously larger than that of conventional solid-state symmetric supercapacitors (≤1 V). It exhibited excellent rate capability with a scan rate as high as 20 V s-1 and a long cyclability (˜60000 cycles) even under severe mechanical deformation. The charge storage mechanism at different scan rates was also quantitatively analyzed.

  3. Flicker

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2013-03-01

    Solid-state lighting program technology fact sheet that discusses flicker metrics, contributing factors, and consequences in addition to comparing the flicker attributes of a sample of conventional and LED sources.

  4. All-solid-state lithium-ion and lithium metal batteries - paving the way to large-scale production

    NASA Astrophysics Data System (ADS)

    Schnell, Joscha; Günther, Till; Knoche, Thomas; Vieider, Christoph; Köhler, Larissa; Just, Alexander; Keller, Marlou; Passerini, Stefano; Reinhart, Gunther

    2018-04-01

    Challenges and requirements for the large-scale production of all-solid-state lithium-ion and lithium metal batteries are herein evaluated via workshops with experts from renowned research institutes, material suppliers, and automotive manufacturers. Aiming to bridge the gap between materials research and industrial mass production, possible solutions for the production chains of sulfide and oxide based all-solid-state batteries from electrode fabrication to cell assembly and quality control are presented. Based on these findings, a detailed comparison of the production processes for a sulfide based all-solid-state battery with conventional lithium-ion cell production is given, showing that processes for composite electrode fabrication can be adapted with some effort, while the fabrication of the solid electrolyte separator layer and the integration of a lithium metal anode will require completely new processes. This work identifies the major steps towards mass production of all-solid-state batteries, giving insight into promising manufacturing technologies and helping stakeholders, such as machine engineering, cell producers, and original equipment manufacturers, to plan the next steps towards safer batteries with increased storage capacity.

  5. Harnessing Solid-State Ionic Transport for Nanomanufacturing and Nanodevices

    ERIC Educational Resources Information Center

    Hsu, Keng Hao

    2009-01-01

    Through this work a new all-solid, ambient processing condition direct metal patterning technique has been developed and characterized. This ionic-transport-based patterning technique is capable of sub-50nm feature resolution under ambient conditions. It generates features with a rate that is comparable to conventional dry-etching techniques. A…

  6. Lowering the operational temperature of all-solid-state lithium polymer cell with highly conductive and interfacially robust solid polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Aldalur, Itziar; Martinez-Ibañez, Maria; Piszcz, Michal; Rodriguez-Martinez, Lide M.; Zhang, Heng; Armand, Michel

    2018-04-01

    Novel solid polymer electrolytes (SPEs), comprising of comb polymer matrix grafted with soft and disordered polyether moieties (Jeffamine®) and lithium bis(fluorosulfonyl)imide (LiFSI) are investigated in all-solid-state lithium metal (Li°) polymer cells. The LiFSI/Jeffamine-based SPEs are fully amorphous at room temperature with glass transitions as low as ca. -55 °C. They show higher ionic conductivities than conventional poly(ethylene oxide) (PEO)-based SPEs at ambient temperature region, and good electrochemical compatibility with Li° electrode. These exceptional properties enable the operational temperature of Li° | LiFePO4 cells to be decreased from an elevated temperature (70 °C) to room temperature. Those results suggest that LiFSI/Jeffamine-based SPEs can be promising electrolyte candidates for developing safe and high performance all-solid-state Li° batteries.

  7. Intermediate couplings: NMR at the solids-liquids interface

    NASA Astrophysics Data System (ADS)

    Spence, Megan

    2006-03-01

    Anisotropic interactions like dipolar couplings and chemical shift anisotropy have long offered solid-state NMR spectroscopists valuable structural information. Recently, solution-state NMR structural studies have begun to exploit residual dipolar couplings of biological molecules in weakly anisotropic solutions. These residual couplings are about 0.1% of the coupling magnitudes observed in the solid state, allowing simple, high-resolution NMR spectra to be retained. In this work, we examine the membrane-associated opioid, leucine enkephalin (lenk), in which the ordering is ten times larger than that for residual dipolar coupling experiments, requiring a combination of solution-state and solid-state NMR techniques. We adapted conventional solid-state NMR techniques like adiabatic cross- polarization and REDOR for use with such a system, and measured small amide bond dipolar couplings in order to determine the orientation of the amide bonds (and therefore the peptide) with respect to the membrane surface. However, the couplings measured indicate large structural rearrangements on the surface and contradict the published structures obtained by NOESY constraints, a reminder that such methods are of limited use in the presence of large-scale dynamics.

  8. All solid-state SBS phase conjugate mirror

    DOEpatents

    Dane, Clifford B.; Hackel, Lloyd A.

    1999-01-01

    A stimulated Brillouin scattering (SBS) phase conjugate laser mirror uses a solid-state nonlinear gain medium instead of the conventional liquid or high pressure gas medium. The concept has been effectively demonstrated using common optical-grade fused silica. An energy threshold of 2.5 mJ and a slope efficiency of over 90% were achieved, resulting in an overall energy reflectivity of >80% for 15 ns, 1 um laser pulses. The use of solid-state materials is enabled by a multi-pass resonant architecture which suppresses transient fluctuations that would otherwise result in damage to the SBS medium. This all solid state phase conjugator is safer, more reliable, and more easily manufactured than prior art designs. It allows nonlinear wavefront correction to be implemented in industrial and defense laser systems whose operating environments would preclude the introduction of potentially hazardous liquids or high pressure gases.

  9. All solid-state SBS phase conjugate mirror

    DOEpatents

    Dane, C.B.; Hackel, L.A.

    1999-03-09

    A stimulated Brillouin scattering (SBS) phase conjugate laser mirror uses a solid-state nonlinear gain medium instead of the conventional liquid or high pressure gas medium. The concept has been effectively demonstrated using common optical-grade fused silica. An energy threshold of 2.5 mJ and a slope efficiency of over 90% were achieved, resulting in an overall energy reflectivity of >80% for 15 ns, 1 um laser pulses. The use of solid-state materials is enabled by a multi-pass resonant architecture which suppresses transient fluctuations that would otherwise result in damage to the SBS medium. This all solid state phase conjugator is safer, more reliable, and more easily manufactured than prior art designs. It allows nonlinear wavefront correction to be implemented in industrial and defense laser systems whose operating environments would preclude the introduction of potentially hazardous liquids or high pressure gases. 8 figs.

  10. Current status of solid-state lithium batteries employing solid redox polymerization cathodes

    NASA Astrophysics Data System (ADS)

    Visco, S. J.; Doeff, M. M.; Dejonghe, L. C.

    1991-03-01

    The rapidly growing demand for secondary batteries having high specific energy and power has naturally led to increased efforts in lithium battery technology. Still, the increased safety risks associated with high energy density systems has tempered the enthusiasm of proponents of such systems for use in the consumer marketplace. The inherent advantages of all-solid-state batteries in regards to safety and reliability are strong factors in advocating their introduction to the marketplace. However, the low ionic conductivity of solid electrolytes relative to nonaqueous liquid electrolytes implies low power densities for solid state systems operating at ambient temperatures. Recent advances in polymer electrolytes have led to the introduction of solid electrolytes having conductivities in the range of 10(exp -4)/ohm cm at room temperature; this is still two orders of magnitude lower than liquid electrolytes. Although these improved ambient conductivities put solid state batteries in the realm of practical devices, it is clear that solid state batteries using such polymeric separators will be thin film devices. Fortunately, thin film fabrication techniques are well established in the plastics and paper industry, and present the possibility of continuous web-form manufacturing. This style of battery manufacture should make solid polymer batteries very cost-competitive with conventional secondary cells. In addition, the greater geometric flexibility of thin film solid state cells should provide benefits in terms of the end-use form factor in device design. This work discusses the status of solid redox polymerization cathodes.

  11. A novel steam explosion sterilization improving solid-state fermentation performance.

    PubMed

    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.

  12. Spatial distribution of organic functional groups supported on mesoporous silica nanoparticles: A study by conventional and DNP-enhanced 29Si solid-state NMR

    DOE PAGES

    Kobayashi, Takeshi; Singappuli-Arachchige, Dilini; Wang, Zhuoran; ...

    2016-12-23

    Solid-state NMR spectroscopy, both conventional and dynamic nuclear polarization (DNP)-enhanced, was employed to study the spatial distribution of organic functional groups attached to the surface of mesoporous silica nanoparticles via co-condensation and grafting. The most revealing information was provided by DNP-enhanced two-dimensional 29Si– 29Si correlation measurements, which unambiguously showed that post-synthesis grafting leads to a more homogeneous dispersion of propyl and mercaptopropyl functionalities than co-condensation. Furthermore, during the anhydrous grafting process, the organosilane precursors do not self-condense and are unlikely to bond to the silica surface in close proximity (less than 4 Å) due to the limited availability of suitablymore » arranged hydroxyl groups.« less

  13. High capacity and stable all-solid-state Li ion battery using SnO2-embedded nanoporous carbon.

    PubMed

    Notohara, Hiroo; Urita, Koki; Yamamura, Hideyuki; Moriguchi, Isamu

    2018-06-08

    Extensive research efforts are devoted to development of high performance all-solid-state lithium ion batteries owing to their potential in not only improving safety but also achieving high stability and high capacity. However, conventional approaches based on a fabrication of highly dense electrode and solid electrolyte layers and their close contact interface is not always applicable to high capacity alloy- and/or conversion-based active materials such as SnO 2 accompanied with large volume change in charging-discharging. The present work demonstrates that SnO 2 -embedded nanoporous carbons without solid electrolyte inside the nanopores are a promising candidate for high capacity and stable anode material of all-solid-state battery, in which the volume change reactions are restricted in the nanopores to keep the constant electrode volume. A prototype all-solid-state full cell consisting of the SnO 2 -based anode and a LiNi 1/3 Co 1 / 3 Mn 1/3 O 2 -based cathode shows a good performance of 2040 Wh/kg at 268.6 W/kg based on the anode material weight.

  14. Determining the environmental training needs and training preferences of tribal officials on reservations in the United States

    NASA Astrophysics Data System (ADS)

    Saxena, Jeeta Lakhani

    The problem of this research was to determine the priority environmental management training needs (drinking water, wastewater, and solid waste), classroom training system preferences and related cultural factors of Native American tribal officials with environmental responsibilities living on reservations in the United States. The researcher conducted telephone interviews with 18 tribal officials on reservations in diverse geographic areas of the United States to determine their classroom training preferences. These officials also responded to a mail/fax survey comprised of 28 statements describing their environmental responsibilities in the areas of drinking water, wastewater, and solid waste. Tribal officials indicated how important the statements were according to them on a scale of 1--5 (1 being low importance and 5 being high importance). Tribal officials also indicated their ability to perform in the stated areas on a scale of 1 to 5 (1 being low ability and 5 being high ability). It was found that tribal officials felt they needed training in the areas of: (1) Solid Waste: Awareness of conventional and alternative solid waste management strategies as well as assessing the reservation's need related to solid waste management. (2) Regional or Inter-Governmental Strategies : Working with the federal, and, state governments for enforcing and developing regulations. (3) Drinking water: Assessing the reservation's drinking water needs and awareness of conventional and alternative drinking water systems. (4) Training for environmental staff: Determining and planning training for environmental personnel is another area of need indicated by the responding tribal officials. (5) Wastewater : Assessing the reservations wastewater needs, compliance and liability issues and awareness of alternative and conventional wastewater systems. It was also found that tribal officials preferred: (1) Trainers who were knowledgeable about the subject matter and tribal culture, problems and issues related to environmental management. (2) Cooperative learning in the form of group exercises and group discussions. Activities such as field trips, case studies or role play were strongly preferred. (3) To receive relevant information from different sources. (4) To attend training within a 200-mile radius. (5) To attend training that was 2--3 days in duration. (6) To attend training sessions organized in circular or U-shaped arrangements.

  15. Potential traceable markers of organic matter in organic and conventional dairy manure using ultraviolet–visible and solid-state 13C nuclear magnetic resonance spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Organic dairy (OD) production is drawing increasing attention because of public concerns about food safety, animal welfare and the potential environmental impacts of conventional dairy (CD) systems. However, very limited information is available on how organic farming practices affect the chemical ...

  16. 'All-solid-state' electrochemistry of a protein-confined polymer electrolyte film

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parthasarathy, Meera; Pillai, Vijayamohanan K.; Mulla, Imtiaz S.

    2007-12-07

    Interfacial redox behavior of a heme protein (hemoglobin) confined in a solid polymer electrolyte membrane, Nafion (a perfluoro sulfonic acid ionomer) is investigated using a unique 'all-solid-state' electrochemical methodology. The supple phase-separated structure of the polymer electrolyte membrane, with hydrophilic pools containing solvated protons and water molecules, is found to preserve the incorporated protein in its active form even in the solid-state, using UV-visible, Fluorescence (of Tryptophan and Tyrosine residues) and DRIFT (diffuse reflectance infrared Fourier transform) spectroscopy. More specifically, solid-state cyclic voltammetry and electrochemical impedance of the protein-incorporated polymer films reveal that the Fe{sup 2+}-form of the entrapped proteinmore » is found to bind molecular oxygen more strongly than the native protein. In the 'all-solid-state' methodology, as there is no need to dip the protein-modified electrode in a liquid electrolyte (like the conventional electrochemical methods), it offers an easier means to study a number of proteins in a variety of polymer matrices (even biomimetic assemblies). In addition, the results of the present investigation could find interesting application in a variety of research disciplines, in addition to its fundamental scientific interest, including protein biotechnology, pharmaceutical and biomimetic chemistry.« less

  17. Addressing the Interface Issues in All-Solid-State Bulk-Type Lithium Ion Battery via an All-Composite Approach.

    PubMed

    Chen, Ru-Jun; Zhang, Yi-Bo; Liu, Ting; Xu, Bing-Qing; Lin, Yuan-Hua; Nan, Ce-Wen; Shen, Yang

    2017-03-22

    All-solid-state bulk-type lithium ion batteries (LIBs) are considered ultimate solutions to the safety issues associated with conventional LIBs using flammable liquid electrolyte. The development of bulk-type all-solid-state LIBs has been hindered by the low loading of active cathode materials, hence low specific surface capacity, and by the high interface resistance, which results in low rate and cyclic performance. In this contribution, we propose and demonstrate a synergistic all-composite approach to fabricating flexible all-solid-state LIBs. PEO-based composite cathode layers (filled with LiFePO 4 particles) of ∼300 μm in thickness and composite electrolyte layers (filled with Al-LLZTO particles) are stacked layer-by-layer with lithium foils as negative layer and hot-pressed into a monolithic all-solid-state LIB. The flexible LIB delivers a high specific discharge capacity of 155 mAh/g, which corresponds to an ultrahigh surface capacity of 10.8 mAh/cm 2 , exhibits excellent capacity retention up to at least 10 cycles and could work properly under harsh operating conditions such as bending or being sectioned into pieces. The all-composite approach is favorable for improving both mesoscopic and microscopic interfaces inside the all-solid-state LIB and may provide a new toolbox for design and fabrication of all-solid-state LIBs.

  18. Novel Nanostructured Solid Materials for Modulating Oral Drug Delivery from Solid-State Lipid-Based Drug Delivery Systems.

    PubMed

    Dening, Tahnee J; Rao, Shasha; Thomas, Nicky; Prestidge, Clive A

    2016-01-01

    Lipid-based drug delivery systems (LBDDS) have gained significant attention in recent times, owing to their ability to overcome the challenges limiting the oral delivery of poorly water-soluble drugs. Despite the successful commercialization of several LBDDS products over the years, a large discrepancy exists between the number of poorly water-soluble drugs displaying suboptimal in vivo performances and the application of LBDDS to mitigate their various delivery challenges. Conventional LBDDS, including lipid solutions and suspensions, emulsions, and self-emulsifying formulations, suffer from various drawbacks limiting their widespread use and commercialization. Accordingly, solid-state LBDDS, fabricated by adsorbing LBDDS onto a chemically inert solid carrier material, have attracted substantial interest as a viable means of stabilizing LBDDS whilst eliminating some of the various limitations. This review describes the impact of solid carrier choice on LBDDS performance and highlights the importance of appropriate solid carrier material selection when designing hybrid solid-state LBDDS. Specifically, emphasis is placed on discussing the ability of the specific solid carrier to modulate drug release, control lipase action and lipid digestion, and enhance biopharmaceutical performance above the original liquid-state LBDDS. To encourage the interested reader to consider their solid carrier choice on a higher level, various novel materials with the potential for future use as solid carriers for LBDDS are described. This review is highly significant in guiding future research directions in the solid-state LBDDS field and fostering the translation of these delivery systems to the pharmaceutical marketplace.

  19. Rapid, cool sintering of wet processed yttria-stabilized zirconia ceramic electrolyte thin films.

    PubMed

    Park, Jun-Sik; Kim, Dug-Joong; Chung, Wan-Ho; Lim, Yonghyun; Kim, Hak-Sung; Kim, Young-Beom

    2017-09-29

    Here we report a photonic annealing process for yttria-stabilized zirconia films, which are one of the most well-known solid-state electrolytes for solid oxide fuel cells (SOFCs). Precursor films were coated using a wet-chemical method with a simple metal-organic precursor solution and directly annealed at standard pressure and temperature by two cycles of xenon flash lamp irradiation. The residual organics were almost completely decomposed in the first pre-annealing step, and the fluorite crystalline phases and good ionic conductivity were developed during the second annealing step. These films showed properties comparable to those of thermally annealed films. This process is much faster than conventional annealing processes (e.g. halogen furnaces); a few seconds compared to tens of hours, respectively. The significance of this work includes the treatment of solid-state electrolyte oxides for SOFCs and the demonstration of the feasibility of other oxide components for solid-state energy devices.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tan, Guoqiang; Wu, Feng; Zhan, Chun

    The development of safe, stable, and long-life Li-ion batteries is being intensively pursued to enable the electrification of transportation and intelligent grid applications. Here, we report a new solid-state Li-ion battery technology, using a solid nanocomposite electrolyte composed of porous silica matrices with in situ immobilizing Li+ conducting ionic liquid, anode material of MCMB, and cathode material of LiCoO 2, LiNi 1/3Co 1/3Mn 1/3O 2, or LiFePO 4. An injection printing method is used for the electrode/electrolyte preparation. Solid nanocomposite electrolytes exhibit superior performance to the conventional organic electrolytes with regard to safety and cycle-life. They also have a transparentmore » glassy structure with high ionic conductivity and good mechanical strength. Solid-state full cells tested with the various cathodes exhibited high specific capacities, long cycling stability, and excellent high temperature performance. This solid-state battery technology will provide new avenues for the rational engineering of advanced Li-ion batteries and other electrochemical devices.« less

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Tony C.; Congreve, Daniel N.; Baldo, Marc A., E-mail: baldo@mit.edu

    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 ismore » 1.1%. Our results demonstrate upconversion in solid state geometries and with non-heavy metal-based sensitizer materials.« less

  2. A Quasi-Solid-State Li-Ion Capacitor Based on Porous TiO2 Hollow Microspheres Wrapped with Graphene Nanosheets.

    PubMed

    Wang, Faxing; Wang, Chun; Zhao, Yujuan; Liu, Zaichun; Chang, Zheng; Fu, Lijun; Zhu, Yusong; Wu, Yuping; Zhao, Dongyuan

    2016-12-01

    The quasi-solid-state Li-ion capacitor is demonstrated with graphene nanosheets prepared by an electrochemical exfoliation as the positive electrode and the porous TiO 2 hollow microspheres wrapped with the same graphene nanosheets as the negative electrode, using a Li-ion conducting gel polymer electrolyte. This device may be the key to bridging the gap between conventional lithium-ion batteries and supercapacitors, meanwhile meeting the safety demands of electronic devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Acoustic Pump

    NASA Technical Reports Server (NTRS)

    Heyman, Joseph S.

    1993-01-01

    Pump uses acoustic-radiation forces. Momentum transferred from sound waves to sound-propagating material in way resulting in net pumping action on material. Acoustic pump is solid-state pump. Requires no moving parts, entirely miniaturized, and does not invade pumped environment. Silent, with no conventional vibration. Used as pump for liquid, suspension, gas, or any other medium interacting with radiation pressure. Also used where solid-state pump needed for reliability and controllability. In microgravity environment, device offers unusual control for low flow rates. For medical or other applications in which contamination cannot be allowed, offers noninvasive pumping force.

  4. Volkov basis for simulation of interaction of strong laser pulses and solids

    NASA Astrophysics Data System (ADS)

    Kidd, Daniel; Covington, Cody; Li, Yonghui; Varga, Kálmán

    2018-01-01

    An efficient and accurate basis comprised of Volkov states is implemented and tested for time-dependent simulations of interactions between strong laser pulses and crystalline solids. The Volkov states are eigenstates of the free electron Hamiltonian in an electromagnetic field and analytically represent the rapidly oscillating time-dependence of the orbitals, allowing significantly faster time propagation than conventional approaches. The Volkov approach can be readily implemented in plane-wave codes by multiplying the potential energy matrix elements with a simple time-dependent phase factor.

  5. Solid state optical microscope

    DOEpatents

    Young, I.T.

    1983-08-09

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal. 2 figs.

  6. Solid-state optical microscope

    DOEpatents

    Young, I.T.

    1981-01-07

    A solid state optical microscope is described wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. Means for scanning in one of two orthogonal directions are provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

  7. Solid state optical microscope

    DOEpatents

    Young, Ian T.

    1983-01-01

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

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

    PubMed

    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.

  9. Screened hybrid density functionals for solid-state chemistry and physics.

    PubMed

    Janesko, Benjamin G; Henderson, Thomas M; Scuseria, Gustavo E

    2009-01-21

    Density functional theory incorporating hybrid exchange-correlation functionals has been extraordinarily successful in providing accurate, computationally tractable treatments of molecular properties. However, conventional hybrid functionals can be problematic for solids. Their nonlocal, Hartree-Fock-like exchange term decays slowly and incorporates unphysical features in metals and narrow-bandgap semiconductors. This article provides an overview of our group's work on designing hybrid functionals for solids. We focus on the Heyd-Scuseria-Ernzerhof screened hybrid functional [J. Chem. Phys. 2003, 118, 8207], its applications to the chemistry and physics of solids and surfaces, and our efforts to build upon its successes.

  10. STUDY ON SYNTHESIS AND EVOLUTION OF NANOCRYSTALLINE Mg4Ta2O9 BY AQUEOUS SOL-GEL PROCESS

    NASA Astrophysics Data System (ADS)

    Wu, H. T.; Yang, C. H.; Wu, W. B.; Yue, Y. L.

    2012-06-01

    Nanosized and highly reactive Mg4Ta2O9 were successfully synthesized by aqueous sol-gel method compared with conventional solid-state method. Ta-Mg-citric acid solution was first formed and then evaporated resulting in a dry gel for calcination in the temperature ranging from 600°C to 800°C for crystallization in oxygen atmosphere. The crystallization process from the gel to crystalline Mg4Ta2O9 was identified by thermal analysis and phase evolution of powders was studied using X-ray diffraction (XRD) technique during calcinations. Particle size and morphology were examined by transmission electron microscopy (TEM) and high resolution scanning electron microscopy (HR-SEM). The results revealed that sol-gel process showed great advantages over conventional solid-state method and Mg4Ta2O9 nanopowders with the size of 20-30 nm were obtained at 800°C.

  11. Conventional physics can explain cold fusion excess heat

    NASA Astrophysics Data System (ADS)

    Chubb, S. R.

    In 1989, when Fleischmann, Pons and Hawkins (FP), claimed they had created room temperature, nuclear fusion in a solid, a firestorm of controversy erupted. Beginning in 1991, the Office of Naval Research began a decade-long study of the FP excess heat effect. This effort documented the fact that the excess heat that FP observed is the result of a form of nuclear fusion that can occur in solids at reduced temperature, dynamically, through a deuteron (d)+d□4He reaction, without high-energy particles or □ rays. A key reason this fact has not been accepted is the lack of a cogent argument, based on fundamental physical ideas, justifying it. In the paper, this question is re-examined, based on a generalization of conventional energy band theory that applies to finite, periodic solids, in which d's are allowed to occupy wave-like, ion band states, similar to the kinds of states that electrons occupy in ordinary metals. Prior to being experimentally observed, the Ion Band State Theory (IBST) of cold fusion predicted a potential d+d□4He reaction, without high energy particles, would explain the excess heat, the 4He would be found in an unexpected place (outside heat-producing electrodes), and high-loading, x□1, in PdDx, would be required.

  12. Experimental Aspects of Polarization Optimized Experiments (POE) for Magic Angle Spinning Solid-State NMR of Microcrystalline and Membrane-Bound Proteins.

    PubMed

    Gopinath, T; Veglia, Gianluigi

    2018-01-01

    Conventional NMR pulse sequences record one spectrum per experiment, while spending most of the time waiting for the spin system to return to the equilibrium. As a result, a full set of multidimensional NMR experiments for biological macromolecules may take up to several months to complete. Here, we present a practical guide for setting up a new class of MAS solid-state NMR experiments (POE or polarization optimized experiments) that enable the simultaneous acquisition of multiple spectra of proteins, accelerating data acquisition. POE exploit the long-lived 15 N polarization of isotopically labeled proteins and enable one to obtain up to eight spectra, by concatenating classical NMR pulse sequences. This new strategy propels data throughput of solid-state NMR spectroscopy of fibers, microcrystalline preparations, as well as membrane proteins.

  13. Protein-nucleotide contacts in motor proteins detected by DNP-enhanced solid-state NMR.

    PubMed

    Wiegand, Thomas; Liao, Wei-Chih; Ong, Ta Chung; Däpp, Alexander; Cadalbert, Riccardo; Copéret, Christophe; Böckmann, Anja; Meier, Beat H

    2017-11-01

    DNP (dynamic nuclear polarization)-enhanced solid-state NMR is employed to directly detect protein-DNA and protein-ATP interactions and identify the residue type establishing the intermolecular contacts. While conventional solid-state NMR can detect protein-DNA interactions in large oligomeric protein assemblies in favorable cases, it typically suffers from low signal-to-noise ratios. We show here, for the oligomeric DnaB helicase from Helicobacter pylori complexed with ADP and single-stranded DNA, that this limitation can be overcome by using DNP-enhanced spectroscopy. Interactions are established by DNP-enhanced 31 P- 13 C polarization-transfer experiments followed by the recording of a 2D 13 C- 13 C correlation experiment. The NMR spectra were obtained in less than 2 days and allowed the identification of residues of the motor protein involved in nucleotide binding.

  14. Structures and fabrication techniques for solid state electrochemical devices

    DOEpatents

    Visco, Steven J.; Jacobson, Craig P.; DeJonghe, Lutgard C.

    2006-10-10

    Low-cost, mechanically strong, highly electronically conductive porous substrates and associated structures for solid-state electrochemical devices, techniques for forming these structures, and devices incorporating the structures provide solid state electrochemical device substrates of novel composition and techniques for forming thin electrode/membrane/electrolyte coatings on the novel or more conventional substrates. In particular, in one aspect the invention provides techniques for co-firing of device substrate (often an electrode) with an electrolyte or membrane layer to form densified electrolyte/membrane films 5 to 20 microns thick. In another aspect, densified electrolyte/membrane films 5 to 20 microns thick may be formed on a pre-sintered substrate by a constrained sintering process. In some cases, the substrate may be a porous metal, alloy, or non-nickel cermet incorporating one or more of the transition metals Cr, Fe and Cu, or alloys thereof.

  15. Conventional and Microwave Joining of Silicon Carbide Using Displacement Reactions

    NASA Technical Reports Server (NTRS)

    Kingsley, J.; Yiin, T.; Barmatz, M.

    1995-01-01

    Microwave heating was used to join Silicon Carbide rods using a thin TiC /Si tape interlayer . Microwaves quickly heated the rods and tape to temperatures where solid-state displacement reactions between TiC and Si occurred.

  16. Synthesis of nano-scale fast ion conducting cubic Li7La3Zr2O12.

    PubMed

    Sakamoto, Jeff; Rangasamy, Ezhiylmurugan; Kim, Hyunjoung; Kim, Yunsung; Wolfenstine, Jeff

    2013-10-25

    A solution-based process was investigated for synthesizing cubic Li7La3Zr2O12 (LLZO), which is known to exhibit the unprecedented combination of fast ionic conductivity, and stability in air and against Li. Sol-gel chemistry was developed to prepare solid metal-oxide networks consisting of 10 nm cross-links that formed the cubic LLZO phase at 600 ° C. Sol-gel LLZO powders were sintered into 96% dense pellets using an induction hot press that applied pressure while heating. After sintering, the average LLZO grain size was 260 nm, which is 13 times smaller compared to LLZO prepared using a solid-state technique. The total ionic conductivity was 0.4 mS cm(-1) at 298 K, which is the same as solid-state synthesized LLZO. Interestingly, despite the same room temperature conductivity, the sol-gel LLZO total activation energy is 0.41 eV, which 1.6 times higher than that observed in solid-state LLZO (0.26 eV). We believe the nano-scale grain boundaries give rise to unique transport phenomena that are more sensitive to temperature when compared to the conventional solid-state LLZO.

  17. "Cooking the sample": radiofrequency induced heating during solid-state NMR experiments.

    PubMed

    d'Espinose de Lacaillerie, Jean-Baptiste; Jarry, Benjamin; Pascui, Ovidiu; Reichert, Detlef

    2005-09-01

    Dissipation of radiofrequency (RF) energy as heat during continuous wave decoupling in solid-state NMR experiment was examined outside the conventional realm of such phenomena. A significant temperature increase could occur while performing dynamic NMR measurements provided the sample contains polar molecules and the sequence calls for relatively long applications of RF power. It was shown that the methyl flip motion in dimethylsulfone (DMS) is activated by the decoupling RF energy conversion to heat during a CODEX pulse sequence. This introduced a significant bias in the correlation time-temperature dependency measurement used to obtain the activation energy of the motion. By investigating the dependency of the temperature increase in hydrated lead nitrate on experimental parameters during high-power decoupling one-pulse experiments, the mechanisms for the RF energy deposition was identified. The samples were heated due to dissipation of the energy absorbed by dielectric losses, a phenomenon commonly known as "microwave" heating. It was thus established that during solid-state NMR experiments at moderate B0 fields, RF heating could lead to the heating of samples containing polar molecules such as hydrated polymers and inorganic solids. In particular, this could result in systematic errors for slow dynamics measurements by solid-state NMR.

  18. All-Solid-State Sodium-Selective Electrode with a Solid Contact of Chitosan/Prussian Blue Nanocomposite

    PubMed Central

    Ghosh, Tanushree; Rieger, Jana

    2017-01-01

    Conventional ion-selective electrodes with a liquid junction have the disadvantage of potential drift. All-solid-state ion-selective electrodes with solid contact in between the metal electrode and the ion-selective membrane offer high capacitance or conductance to enhance potential stability. Solution-casted chitosan/Prussian blue nanocomposite (ChPBN) was employed as the solid contact layer for an all-solid-state sodium ion-selective electrode in a potentiometric sodium ion sensor. Morphological and chemical analyses confirmed that the ChPBN is a macroporous network of chitosan that contains abundant Prussian blue nanoparticles. Situated between a screen-printed carbon electrode and a sodium-ionophore-filled polyvinylchloride ion-selective membrane, the ChPBN layer exhibited high redox capacitance and fast charge transfer capability, which significantly enhanced the performance of the sodium ion-selective electrode. A good Nernstian response with a slope of 52.4 mV/decade in the linear range from 10−4–1 M of NaCl was observed. The stability of the electrical potential of the new solid contact was tested by chronopotentiometry, and the capacitance of the electrode was 154 ± 4 µF. The response stability in terms of potential drift was excellent (1.3 µV/h) for 20 h of continuous measurement. The ChPBN proved to be an efficient solid contact to enhance the potential stability of the all-solid-state ion-selective electrode. PMID:29099804

  19. Wafer-scale development and experimental verification of 0.36 mm2 228 mV open-circuit-voltage solid-state CMOS-compatible glucose fuel cell

    NASA Astrophysics Data System (ADS)

    Arata, Shigeki; Hayashi, Kenya; Nishio, Yuya; Kobayashi, Atsuki; Nakazato, Kazuo; Niitsu, Kiichi

    2018-04-01

    The world’s smallest (0.36 mm2) solid-state CMOS-compatible glucose fuel cell, which exhibits an open-circuit voltage (OCV) of 228 mV and a power generation density of 1.32 µW/cm2 with a 30 mM glucose solution, is reported in this paper. Compared with conventional wet etching, dry etching (reactive ion etching) for patterning minimizes damage to the anode and cathode, resulting in a cell with a small size and a high OCV, sufficient for CMOS circuit operation.

  20. Facile solid-state synthesis of oxidation-resistant metal nanoparticles at ambient conditions

    NASA Astrophysics Data System (ADS)

    Lee, Kyu Hyung; Jung, Hyuk Joon; Lee, Ju Hee; Kim, Kyungtae; Lee, Byeongno; Nam, Dohyun; Kim, Chung Man; Jung, Myung-Hwa; Hur, Nam Hwi

    2018-05-01

    A simple and scalable method for the synthesis of metal nanoparticles in the solid-state was developed, which can produce nanoparticles in the absence of solvents. Nanoparticles of coinage metals were synthesized by grinding solid hydrazine and the metal precursors in their acetates and oxides at 25 °C. The silver and gold acetates converted completely within 6 min into Ag and Au nanoparticles, respectively, while complete conversion of the copper acetate to the Cu sub-micrometer particles took about 2 h. Metal oxide precursors were also converted into metal nanoparticles by grinding alone. The resulting particles exhibit distinctive crystalline lattice fringes, indicating the formation of highly crystalline phases. The Cu sub-micrometer particles are better resistant to oxidation and exhibit higher conductivity compared to conventional Cu nanoparticles. This solid-state method was also applied for the synthesis of platinum group metals and intermetallic Cu3Au, which can be further extended to synthesize other metal nanoparticles.

  1. Modeling an in-register, parallel "iowa" aβ fibril structure using solid-state NMR data from labeled samples with rosetta.

    PubMed

    Sgourakis, Nikolaos G; Yau, Wai-Ming; Qiang, Wei

    2015-01-06

    Determining the structures of amyloid fibrils is an important first step toward understanding the molecular basis of neurodegenerative diseases. For β-amyloid (Aβ) fibrils, conventional solid-state NMR structure determination using uniform labeling is limited by extensive peak overlap. We describe the characterization of a distinct structural polymorph of Aβ using solid-state NMR, transmission electron microscopy (TEM), and Rosetta model building. First, the overall fibril arrangement is established using mass-per-length measurements from TEM. Then, the fibril backbone arrangement, stacking registry, and "steric zipper" core interactions are determined using a number of solid-state NMR techniques on sparsely (13)C-labeled samples. Finally, we perform Rosetta structure calculations with an explicitly symmetric representation of the system. We demonstrate the power of the hybrid Rosetta/NMR approach by modeling the in-register, parallel "Iowa" mutant (D23N) at high resolution (1.2Å backbone rmsd). The final models are validated using an independent set of NMR experiments that confirm key features. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Solid-state supercapacitors with rationally designed heterogeneous electrodes fabricated by large area spray processing for wearable energy storage applications.

    PubMed

    Huang, Chun; Zhang, Jin; Young, Neil P; Snaith, Henry J; Grant, Patrick S

    2016-05-10

    Supercapacitors are in demand for short-term electrical charge and discharge applications. Unlike conventional supercapacitors, solid-state versions have no liquid electrolyte and do not require robust, rigid packaging for containment. Consequently they can be thinner, lighter and more flexible. However, solid-state supercapacitors suffer from lower power density and where new materials have been developed to improve performance, there remains a gap between promising laboratory results that usually require nano-structured materials and fine-scale processing approaches, and current manufacturing technology that operates at large scale. We demonstrate a new, scalable capability to produce discrete, multi-layered electrodes with a different material and/or morphology in each layer, and where each layer plays a different, critical role in enhancing the dynamics of charge/discharge. This layered structure allows efficient utilisation of each material and enables conservative use of hard-to-obtain materials. The layered electrode shows amongst the highest combinations of energy and power densities for solid-state supercapacitors. Our functional design and spray manufacturing approach to heterogeneous electrodes provide a new way forward for improved energy storage devices.

  3. [Fundamentals of plasma chemistry and its application to drug engineering].

    PubMed

    Kuzuya, M

    1996-04-01

    In this review, our novel research works in both low temperature plasma chemistry and solid state plasma chemistry were described. As for low temperature plasma, the ESR study on plasma-induced radicals of several selected conventional polymers was shown including the detailed analyses of the radical structure and the mechanism by which the radicals were formed on typical degradable methacrylic polymers and cross-linkable polystyrene. One of the pharmaceutical applications of the plasma processing for drug delivery system (DDS) was also described, which includes the preparations of double-compressed tablet consisting of drugs as a core material and various types of polymers as a wall material followed by plasma-irradiation on such a tablet. As for solid state plasma, the detailed reaction mechanism of solid state mechanochemical polymerization was shown including the solid state single electron transfer and the special feature of the resulting polymers. The structural criteria for polymerizable monomer derived from the quantum chemical considerations were also established. Based on the above findings, we synthesized various polymeric prodrugs by mechanochemical polymerization and studied the nature of hydrolyses (drug release).

  4. Rapid acquisition of data dense solid-state CPMG NMR spectral sets using multi-dimensional statistical analysis

    DOE PAGES

    Mason, H. E.; Uribe, E. C.; Shusterman, J. A.

    2018-01-01

    Tensor-rank decomposition methods have been applied to variable contact time 29 Si{ 1 H} CP/CPMG NMR data sets to extract NMR dynamics information and dramatically decrease conventional NMR acquisition times.

  5. Rapid acquisition of data dense solid-state CPMG NMR spectral sets using multi-dimensional statistical analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mason, H. E.; Uribe, E. C.; Shusterman, J. A.

    Tensor-rank decomposition methods have been applied to variable contact time 29 Si{ 1 H} CP/CPMG NMR data sets to extract NMR dynamics information and dramatically decrease conventional NMR acquisition times.

  6. A mass diffusion-based interpretation of the effect of total solids content on solid-state anaerobic digestion of cellulosic biomass.

    PubMed

    Xu, Fuqing; Wang, Zhi-Wu; Tang, Li; Li, Yebo

    2014-09-01

    In solid-state anaerobic digestion (SS-AD) of cellulosic biomass, the volumetric methane production rate has often been found to increase with the increase in total solids (TS) content until a threshold is reached, and then to decrease. This phenomenon cannot be explained by conventional understanding derived from liquid anaerobic digestion. This study proposed that the high TS content-caused mass diffusion limitation may be responsible for the observed methane production deterioration. Based on this hypothesis, a new SS-AD model was developed by taking into account the mass diffusion limitation and hydrolysis inhibition. The good agreement between model simulation and the experimental as well as literature data verified that the observed reduction in volumetric methane production rate could be ascribed to hydrolysis inhibition as a result of the mass diffusion limitation in SS-AD. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Structures And Fabrication Techniques For Solid State Electrochemical Devices

    DOEpatents

    Visco, Steven J.; Jacobson, Craig P.; DeJonghe, Lutgard C.

    2005-12-27

    Provided are low-cost, mechanically strong, highly electronically conductive porous substrates and associated structures for solid-state electrochemical devices, techniques for forming these structures, and devices incorporating the structures. The invention provides solid state electrochemical device substrates of novel composition and techniques for forming thin electrode/membrane/electrolyte coatings on the novel or more conventional substrates. In particular, in one embodiment the invention provides techniques for co-firing of device substrate (often an electrode) with an electrolyte or membrane layer to form densified electrolyte/membrane films 5 to 20 microns thick. In another embodiment, densified electrolyte/membrane films 5 to 20 microns thick may be formed on a pre-sintered substrate by a constrained sintering process. In some cases, the substrate may be a porous metal, alloy, or non-nickel cermet incorporating one or more of the transition metals Cr, Fe, Cu and Ag, or alloys thereof.

  8. Structures and fabrication techniques for solid state electrochemical devices

    DOEpatents

    Visco, Steven J.; Jacobson, Craig P.; DeJonghe, Lutgard C.

    2003-08-12

    Provided are low-cost, mechanically strong, highly electronically conductive porous substrates and associated structures for solid-state electrochemical devices, techniques for forming these structures, and devices incorporating the structures. The invention provides solid state electrochemical device substrates of novel composition and techniques for forming thin electrode/membrane/electrolyte coatings on the novel or more conventional substrates. In particular, in one embodiment the invention provides techniques for co-firing of device substrate (often an electrode) with an electrolyte or membrane layer to form densified electrolyte/membrane films 5 to 20 microns thick. In another embodiment, densified electrolyte/membrane films 5 to 20 microns thick may be formed on a pre-sintered substrate by a constrained sintering process. In some cases, the substrate may be a porous metal, alloy, or non-nickel cermet incorporating one or more of the transition metals Cr, Fe, Cu and Ag, or alloys thereof.

  9. Endothelial cell density after photorefractive keratectomy for moderate myopia using a 213 nm solid-state laser system.

    PubMed

    Tsiklis, Nikolaos S; Kymionis, George D; Pallikaris, Aristofanis I; Diakonis, Vasilios F; Ginis, Harilaos S; Kounis, George A; Panagopoulou, Sophia I; Pallikaris, Ioannis G

    2007-11-01

    To evaluate whether photorefractive keratectomy (PRK) for moderate myopia using a solid-state laser with a wavelength of 213 nm alters the corneal endothelial cell density. University refractive surgery center. The corneal endothelium was analyzed preoperatively and 1, 6, and 12 months postoperatively using corneal confocal microscopy (modified HRT II with a Rostock Cornea Module, Heidelberg Engineering) in 60 eyes (30 patients). Patients were randomized to have myopic PRK using a 213 nm wavelength solid-state laser (study group) or a conventional 193 nm wavelength excimer laser (control group). Three endothelial images were acquired in each of 30 preoperative normal eyes to evaluate the repeatability of endothelial cell density measurements. Repeated-measures analysis of variance was used to compare the variations in endothelial cell density between the 2 lasers and the changes in endothelial cell density over time. There were no statistically significant differences in sex, age, corneal pachymetry, attempted correction, preoperative endothelial cell density, or postoperative refractive outcomes (uncorrected visual acuity, best spectacle-corrected visual acuity, and spherical equivalent refraction) between the 2 groups (P>.05). The coefficient of repeatability of endothelial cell density was 131 cells/mm(2). The measured endothelial cell count per 1.0 mm(2) did not significantly change up to 1 year postoperatively in either group (both P>.05). No statistically significant difference was found between the 2 groups in any postoperative interval (P>.05). Photorefractive keratectomy for moderate myopia using a 213 nm wavelength solid-state laser or a conventional 193 nm wavelength excimer laser did not significantly affect corneal endothelial density during the 1-year postoperative period.

  10. Beyond flexible batteries: aesthetically versatile, printed rechargeable power sources for smart electronics

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Young

    2017-05-01

    Forthcoming wearable/flexible electronics with compelling shape diversity and mobile usability have garnered significant attention as a kind of disruptive technology to drastically change our daily lives. From a power source point of view, conventional rechargeable batteries (represented by lithium-ion batteries) with fixed shapes and dimensions are generally fabricated by winding (or stacking) cell components (such as anodes, cathodes and separator membranes) and then packaging them with (cylindrical-/rectangular-shaped) metallic canisters or pouch films, finally followed by injection of liquid electrolytes. In particular, the use of liquid electrolytes gives rise to serious concerns in cell assembly, because they require strict packaging materials to avoid leakage problems and also separator membranes to prevent electrical contact between electrodes. For these reasons, the conventional cell assembly and materials have pushed the batteries to lack of variety in form factors, thus imposing formidable challenges on their integration into versatile-shaped electronic devices. Here, as a facile and efficient strategy to address the aforementioned longstanding challenge, we demonstrate a new class of printed solid-state Li-ion batteries and also all-inkjet-printed solid-state supercapacitors with exceptional shape conformability and aesthetic versatility which lie far beyond those achievable with conventional battery technologies.

  11. Preliminary Analysis of a Fully Solid State Magnetocaloric Refrigeration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abdelaziz, Omar

    Magnetocaloric refrigeration is an alternative refrigeration technology with significant potential energy savings compared to conventional vapor compression refrigeration technology. Most of the reported active magnetic regenerator (AMR) systems that operate based on the magnetocaloric effect use heat transfer fluid to exchange heat, which results in complicated mechanical subsystems and components such as rotating valves and hydraulic pumps. In this paper, we propose an alternative mechanism for heat transfer between the AMR and the heat source/sink. High-conductivity moving rods/sheets (e.g. copper, brass, iron, graphite, aluminum or composite structures from these) are utilized instead of heat transfer fluid significantly enhancing the heatmore » transfer rate hence cooling/heating capacity. A one-dimensional model is developed to study the solid state AMR. In this model, the heat exchange between the solid-solid interfaces is modeled via a contact conductance, which depends on the interface apparent pressure, material hardness, thermal conductivity, surface roughness, surface slope between the interfaces, and material filled in the gap between the interfaces. Due to the tremendous impact of the heat exchange on the AMR cycle performance, a sensitivity analysis is conducted employing a response surface method, in which the apparent pressure, effective surface roughness and grease thermal conductivity are the uncertainty factors. COP and refrigeration capacity are presented as the response in the sensitivity analysis to reveal the important factors influencing the fully solid state AMR and optimize the solid state AMR efficiency. The performances of fully solid state AMR and traditional AMR are also compared and discussed in present work. The results of this study will provide general guidelines for designing high performance solid state AMR systems.« less

  12. Electrochemical Stability of Li 10GeP 2S 12 and Li 7La 3Zr 2O 12 Solid Electrolytes

    DOE PAGES

    Han, Fudong; Zhu, Yizhou; He, Xingfeng; ...

    2016-01-21

    The electrochemical stability window of solid electrolyte is overestimated by the conventional experimental method using a Li/electrolyte/inert metal semiblocking electrode because of the limited contact area between solid electrolyte and inert metal. Since the battery is cycled in the overestimated stability window, the decomposition of the solid electrolyte at the interfaces occurs but has been ignored as a cause for high interfacial resistances in previous studies, limiting the performance improvement of the bulk-type solid-state battery despite the decades of research efforts. Thus, there is an urgent need to identify the intrinsic stability window of the solid electrolyte. The thermodynamic electrochemicalmore » stability window of solid electrolytes is calculated using first principles computation methods, and an experimental method is developed to measure the intrinsic electrochemical stability window of solid electrolytes using a Li/electrolyte/electrolyte-carbon cell. The most promising solid electrolytes, Li10GeP2S12 and cubic Li-garnet Li7La3Zr2O12, are chosen as the model materials for sulfide and oxide solid electrolytes, respectively. The results provide valuable insights to address the most challenging problems of the interfacial stability and resistance in high-performance solid-state batteries.« less

  13. Mechanism of Formation of Li 7 P 3 S 11 Solid Electrolytes through Liquid Phase Synthesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Yuxing; Lu, Dongping; Bowden, Mark

    Crystalline Li7P3S11 is a promising solid electrolyte for all solid state lithium/lithium ion batteries. A controllable liquid phase synthesis of Li7P3S11 is more desirable compared to conventional mechanochemical synthesis, but recent attempts suffer from reduced ionic conductivities. Here we elucidate the formation mechanism of crystalline Li7P3S11 synthesized in the liquid phase (acetonitrile, or ACN). We conclude that the crystalline Li7P3S11 forms through a two-step reaction: 1) formation of solid Li3PS4∙ACN and amorphous Li2S∙P2S5 phases in the liquid phase; 2) solid-state conversion of the two phases. The implication of this two-step reaction mechanism to the morphology control and the transport propertiesmore » of liquid phase synthesized Li7P3S11 is identified and discussed.« less

  14. A comprehensive in vitro study of image accuracy and quality for periodontal diagnosis. Part 1: the influence of X-ray generator on periodontal measurements using conventional and digital receptors.

    PubMed

    Vandenberghe, Bart; Corpas, Livia; Bosmans, Hilde; Yang, Jie; Jacobs, Reinhilde

    2011-08-01

    The aim of this study was the determination of image accuracy and quality for periodontal diagnosis using various X-ray generators with conventional and digital radiographs. Thirty-one in vitro periodontal defects were evaluated on intraoral conventional (E-, F/E-speed) and digital images (three indirect, two direct sensors). Standardised radiographs were made with an alternating current (AC), a high-frequency (HF) and a direct current (DC) X-ray unit at rising exposure times (20-160 ms with 20-ms interval) with a constant kV of 70. Three observers assessed bone levels for comparison to the gold standard. Lamina dura, contrast, trabecularisation, crater and furcation involvements were evaluated. Irrespective X-ray generator-type, measurement deviations increased at higher exposure times for solid-state, but decreased for photostimulable storage phosphor (PSP) systems. Accuracy for HF or DC was significantly higher than AC (p < 0.0001), especially at low exposure times. At 0.5- to 1-mm clinical deviation, 27-53% and 32-55% dose savings were demonstrated when using HF or DC generators compared to AC, but only for PSP. No savings were found for solid-state sensors, indicating their higher sensitivity. The use of digital sensors compared to film allowed 15-90% dose savings using the AC tube, whilst solid-state sensors allowed approximately 50% savings compared to PSP, depending on tube type and threshold level.. Accuracy of periodontal diagnosis increases when using HF or DC generators and/or digital receptors with adequate diagnostic information at lower exposure times.

  15. Printable Solid-State Lithium-Ion Batteries: A New Route toward Shape-Conformable Power Sources with Aesthetic Versatility for Flexible Electronics.

    PubMed

    Kim, Se-Hee; Choi, Keun-Ho; Cho, Sung-Ju; Choi, Sinho; Park, Soojin; Lee, Sang-Young

    2015-08-12

    Forthcoming flexible/wearable electronic devices with shape diversity and mobile usability garner a great deal of attention as an innovative technology to bring unprecedented changes in our daily lives. From the power source point of view, conventional rechargeable batteries (one representative example is a lithium-ion battery) with fixed shapes and sizes have intrinsic limitations in fulfilling design/performance requirements for the flexible/wearable electronics. Here, as a facile and efficient strategy to address this formidable challenge, we demonstrate a new class of printable solid-state batteries (referred to as "PRISS batteries"). Through simple stencil printing process (followed by ultraviolet (UV) cross-linking), solid-state composite electrolyte (SCE) layer and SCE matrix-embedded electrodes are consecutively printed on arbitrary objects of complex geometries, eventually leading to fully integrated, multilayer-structured PRISS batteries with various form factors far beyond those achievable by conventional battery technologies. Tuning rheological properties of SCE paste and electrode slurry toward thixotropic fluid characteristics, along with well-tailored core elements including UV-cured triacrylate polymer and high boiling point electrolyte, is a key-enabling technology for the realization of PRISS batteries. This process/material uniqueness allows us to remove extra processing steps (related to solvent drying and liquid-electrolyte injection) and also conventional microporous separator membranes, thereupon enabling the seamless integration of shape-conformable PRISS batteries (including letters-shaped ones) into complex-shaped objects. Electrochemical behavior of PRISS batteries is elucidated via an in-depth analysis of cell impedance, which provides a theoretical basis to enable sustainable improvement of cell performance. We envision that PRISS batteries hold great promise as a reliable and scalable platform technology to open a new concept of cell architecture and fabrication route toward flexible power sources with exceptional shape conformability and aesthetic versatility.

  16. Lithium Metal-Copper Vanadium Oxide Battery with a Block Copolymer Electrolyte

    DOE PAGES

    Devaux, Didier; Wang, Xiaoya; Thelen, Jacob L.; ...

    2016-09-08

    Lithium (Li) batteries comprising multivalent positive active materials such as copper vanadium oxide have high theoretical capacity. These batteries with a conventional liquid electrolyte exhibit limited cycle life because of copper dissolution into the electrolyte. In this paper, we report here on the characterization of solid-state Li metal batteries with a positive electrode based on α-Cu 6.9V 6O 18.9 (α-CuVO 3). We replaced the liquid electrolyte by a nanostructured solid block copolymer electrolyte comprising of a mixture of polystyrene-b-poly(ethylene oxide) (SEO) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt. In situ X-ray diffraction was used to follow the Li insertion/de-insertion mechanism into themore » α-CuVO 3 host material and its reversibility. In situ X-ray scattering revealed that the multistep electrochemical reactions involved are similar in the presence of liquid or solid electrolyte. The capacity fade of the solid-state batteries is less rapid than that of α-CuVO 3–Li metal batteries with a conventional liquid electrolyte. Hard X-ray microtomography revealed that upon cycling, voids and Cu-rich agglomerates were formed at the interface between the Li metal and the SEO electrolyte. Finally, the void volume and the volume occupied by the Cu-rich agglomerates were independent of C-rate and cycle number.« less

  17. Mechanical and Thermal Properties of Dental Composites Cured with CAD/CAM Assisted Solid-State Laser

    PubMed Central

    De Santis, Roberto; Gloria, Antonio; Maietta, Saverio; Martorelli, Massimo; De Luca, Alessandro; Spagnuolo, Gianrico; Riccitiello, Francesco; Rengo, Sandro

    2018-01-01

    Over the last three decades, it has been frequently reported that the properties of dental restorative composites cured with argon laser are similar or superior to those achieved with conventional halogen and light emitting diode (LED) curing units. Whereas laser curing is not dependent on the distance between the curing unit and the material, such distance represents a drawback for conventional curing units. However, a widespread clinical application of this kind of laser remains difficult due to cost, heavy weight, and bulky size. Recently, with regard to the radiation in the blue region of the spectrum, powerful solid-state lasers have been commercialized. In the current research, CAD (computer-aided design)/CAM (computer-aided manufacturing) assisted solid-state lasers were employed for curing of different dental restorative composites consisting of micro- and nanoparticle-reinforced materials based on acrylic resins. Commercial LED curing units were used as a control. Temperature rise during the photopolymerisation process and bending properties were measured. By providing similar light energy dose, no significant difference in temperature rise was observed when the two light sources provided similar intensity. In addition, after 7 days since curing, bending properties of composites cured with laser and LED were similar. The results suggested that this kind of laser would be suitable for curing dental composites, and the curing process does not suffer from the tip-to-tooth distance. PMID:29584683

  18. gamma. -irradiated sewage solids in diets for sheep: nutritive evaluations and long-term assessments of possible toxicants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sanson, D.W.

    1983-01-01

    Air-dried solids from primary (undigested) sewage sludge were collected at Las Cruces, New Mexico (a non-industrial town with population about 50,000). Bagged sewage solids were ..gamma..-irradiated (1 megarad dosage) to kill parasites and pathogenic organisms and evaluated as prospective feedstuffs for sheep. Pelleted, complete diets for gestating-lactating fine-wool ewes and for their growing-finishing lambs were formulated to be isonitrogenous with either 3.5% cottonseed meal (conventional diet) or 7% sewage solids (experimental diet). Digestibility of organic matter and crude protein, and biological value of nitrogen, did not differ (P > .05) between diets, as determined with wethers. Wether lambs fed tomore » slaughter with conventional or experimental diets did not differ (P > .05) in rate of gain, carcass characteristics, element concentrations in blood and serum chemistry profiles, although liver Cu and kidney Pb levels were increased (P < .05) about 1.6-fold by sewage solids. Element contents of spleen and muscles did not differ (P > .05) due to diets. These studies confirm previous research at New Mexico State University which indicates that dried solids from municipal (primary) sludge provide nutritive benefits to sheep with risks of toxicity and heavy metal accumulation that appear tolerable where managed properly.« less

  19. Semiconductor Laser Diode Arrays by MOCVD (Metalorganic Chemical Vapor Deposition)

    DTIC Science & Technology

    1987-09-01

    laser diode arrays are intended to be used as an optical pump for solid state yttrium aluminum garnet (YAG) lasers. In particular, linear uniform...corresponds to about . , 8080A. Such thin layer structures, while difficult to grow by such conventional growth methods as liquid phase epitaxy ( LPE ...lower yet than for DH lasers grown by LPE . , - Conventional self-aligned stripe laser This structure is formed by growing (on an n-type GaAs substrate

  20. Solid state power controllers

    NASA Technical Reports Server (NTRS)

    Gibbs, R. S.

    1974-01-01

    Solid state power controllers (SSPC's) are to be considered for use as replacements of electromechanical relays and circuit breakers in future spacecraft and aircraft. They satisfy the combined function of both the relay and circuit breaker and can be remotely controlled by small signals, typically 10 mA, 5 to 28 v(dc). They have the advantage over conventional relay/circuit breaker systems in that they can be located near the utilization equipment and the primary ac or dc bus. The low level control, trip indication and status signals can be circuited by small gauge wire for control, computer interface, logic, electrical multiplexing, onboard testing, power management, and distribution purposes. This results in increased system versatility at appreciable weight saving and increased reliability. Conventional systems require the heavy gage load wiring and the control wiring to be routed from the bus to the load to other remote relay contacts, switches, sensors, etc. and to the circuit breaker located in the flight engineer's compartment for purposes of manual reset.

  1. Development of an integrated electrochemical system for in vitro yeast viability testing.

    PubMed

    Adami, Andrea; Ress, Cristina; Collini, Cristian; Pedrotti, Severino; Lorenzelli, Leandro

    2013-02-15

    This work describes the development and testing of a microfabricated sensor for rapid cell growth monitoring, especially focused on yeast quality assessment for wine applications. The device consists of a NMOS ISFET sensor with Si(3)N(4) gate, able to indirectly monitor extracellular metabolism through pH variation of the medium, and a solid-state reference electrode implemented with PVC membranes doped with lipophilic salts (tetrabutylammonium-tetrabutylborate (TBA-TBB) and Potassium tetrakis(4-chlorphenyl)borate (KTClpB)). The use of a solid state reference electrode enables the implementation of a large number of cell assays in parallel, without the need of external conventional reference electrodes. Microbial growth testing has been performed both in standard culture conditions and on chip at different concentrations of ethanol in order to carry out a commonly used screening of wine yeast strains. Cell growth tests can be performed in few hours, providing a fast, sensitive and low cost analysis with respect to the conventional procedures. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Cleaner processing: a sulphide-free approach for depilation of skins.

    PubMed

    Ranjithkumar, Ammasi; Durga, Jayanthi; Ramesh, Ramakrishnan; Rose, Chellan; Muralidharan, Chellappa

    2017-01-01

    The conventional unhairing process in leather making utilises large amount of lime and sodium sulphide which is hazardous and poses serious waste disposal concerns. Under acidic conditions, sodium sulphide liberates significant quantities of hydrogen sulphide which causes frequent fatal accidents. Further, the conventional unhairing process involves destruction of the hair leading to increased levels of biological oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS) and total suspended solids (TSS) in the effluent. A safe approach is needed to overcome such environmental and health problems through an eco-benign process. The present study deals with a clean technology in which the keratinous body is detached from the dermis using enzymes produced from Bacillus crolab MTCC 5468 by solid state fermentation (SSF) as an alternative to noxious chemicals. Complete unhairing of skin could be achieved with an enzyme concentration of 1.2 % (w/w). The bio-chemical parameters of the spent liquor of the enzymatic process were environmentally favourable when compared with conventional method. The study indicates that the enzymatic unhairing is a safe process which could be used effectively in leather processing to alleviate pollution and health problems.

  3. Peculiarities of methane clathrate hydrate formation and solid-state deformation, including possible superheating of water ice

    USGS Publications Warehouse

    Stern, L.A.; Kirby, S.H.; Durham, W.B.

    1996-01-01

    Slow, constant-volume heating of water ice plus methane gas mixtures forms methane clathrate hydrate by a progressive reaction that occurs at the nascent ice/liquid water interface. As this reaction proceeds, the rate of melting of metastable water ice may be suppressed to allow short-lived superheating of ice to at least 276 kelvin. Plastic flow properties measured on clathrate test specimens are significantly different from those of water ice; under nonhydrostatic stress, methane clathrate undergoes extensive strain hardening and a process of solid-state disproportionation or exsolution at conditions well within its conventional hydrostatic stability field.

  4. High Speed Solid State Circuit Breaker

    NASA Technical Reports Server (NTRS)

    Podlesak, Thomas F.

    1993-01-01

    The U.S. Army Research Laboratory, Fort Monmouth, NJ, has developed and is installing two 3.3 MW high speed solid state circuit breakers at the Army's Pulse Power Center. These circuit breakers will interrupt 4160V three phase power mains in no more than 300 microseconds, two orders of magnitude faster than conventional mechanical contact type circuit breakers. These circuit breakers utilize Gate Turnoff Thyristors (GTO's) and are currently utility type devices using air cooling in an air conditioned enclosure. Future refinements include liquid cooling, either water or two phase organic coolant, and more advanced semiconductors. Each of these refinements promises a more compact, more reliable unit.

  5. Solid-state NMR adiabatic TOBSY sequences provide enhanced sensitivity for multidimensional high-resolution magic-angle-spinning 1H MR spectroscopy

    NASA Astrophysics Data System (ADS)

    Andronesi, Ovidiu C.; Mintzopoulos, Dionyssios; Struppe, Jochem; Black, Peter M.; Tzika, A. Aria

    2008-08-01

    We propose a solid-state NMR method that maximizes the advantages of high-resolution magic-angle-spinning (HRMAS) applied to intact biopsies when compared to more conventional liquid-state NMR approaches. Theoretical treatment, numerical simulations and experimental results on intact human brain biopsies are presented. Experimentally, it is proven that an optimized adiabatic TOBSY (TOtal through Bond correlation SpectroscopY) solid-state NMR pulse sequence for two-dimensional 1H- 1H homonuclear scalar-coupling longitudinal isotropic mixing provides a 20%-50% improvement in signal-to-noise ratio relative to its liquid-state analogue TOCSY (TOtal Correlation SpectroscopY). For this purpose we have refined the C9151 symmetry-based 13C TOBSY pulse sequence for 1H MRS use and compared it to MLEV-16 TOCSY sequence. Both sequences were rotor-synchronized and implemented using WURST-8 adiabatic inversion pulses. As discussed theoretically and shown in simulations, the improved magnetization-transfer comes from actively removing residual dipolar couplings from the average Hamiltonian. Importantly, the solid-state NMR techniques are tailored to perform measurements at low temperatures where sample degradation is reduced. This is the first demonstration of such a concept for HRMAS metabolic profiling of disease processes, including cancer, from biopsies requiring reduced sample degradation for further genomic analysis.

  6. Preparation of the polyelectrolyte complex hydrogel of biopolymers via a semi-dissolution acidification sol-gel transition method and its application in solid-state supercapacitors

    NASA Astrophysics Data System (ADS)

    Zhao, Jian; Chen, Yu; Yao, Ying; Tong, Zong-Rui; Li, Pu-Wang; Yang, Zi-Ming; Jin, Shao-Hua

    2018-02-01

    Hydrogels have drawn many attentions as the solid-state electrolytes in flexible solid-state supercapacitors (SCs) recently. Among them, the polyelectrolyte complex hydrogel (PECH) electrolytes of natural polymers are more competitive because of their environmentally friendly property and low cost. However, while mixing two biopolymer solutions with opposite charges, the strong electrostatic interactions between the cationic and anionic biopolymers may result in precipitates instead of hydrogels. Here we report a novel method, semi-dissolution acidification sol-gel transition (SD-A-SGT), for the preparation of the PECH of chitosan (CTS) and sodium alginate (SA), with the controllable sol-gel transition and uniform composition and successfully apply it as the hydrogel electrolyte of solid-state supercapacitors (SCs). The CTS-SA PECH exhibits an extremely high ionic conductivity of 0.051 S·cm-1 and reasonable mechanical properties with a tensile strength of 0.29 MPa and elongation at break of 109.5%. The solid-state SC fabricated with the CTS-SA PECH and conventional polyaniline (PANI) nanowire electrodes provided a high specific capacitance of 234.6 F·g-1 at 5 mV·s-1 and exhibited excellent cycling stability with 95.3% capacitance retention after 1000 cycles. Our work may pave a novel avenue to the preparation of biodegradable PECHs of full natural polymers, and promote the development of environmentally friendly electronic devices.

  7. Promises and challenges in solid-state lighting

    NASA Astrophysics Data System (ADS)

    Schubert, Fred

    2010-03-01

    Lighting technologies based on semiconductor light-emitting diodes (LEDs) offer unprecedented promises that include three major benefits: (i) Gigantic energy savings enabled by efficient conversion of electrical energy to optical energy; (ii) Substantial positive contributions to sustainability through reduced emissions of global-warming gases, acid-rain gases, and toxic substances such as mercury; and (iii) The creation of new paradigms in lighting driven by the unique controllability of solid-state lighting sources. Due to the powerful nature of these benefits, the transition from conventional lighting sources to solid-state lighting is virtually assured. This presentation will illustrate the new world of lighting and illustrate the pervasive changes to be expected in lighting, displays, communications, and biotechnology. The presentation will also address the formidable challenges that must be addressed to continue the further advancement of solid-state lighting technology. These challenges offer opportunities for research and innovation. Specific challenges include light management, carrier transport, and optical design. We will present some innovative approaches in order to solve known technical challenges faced by solid-state lighting. These approaches include the demonstration and use of new optical thin-film materials with a continuously tunable refractive index. These approaches also include the use of polarization-matched structures that reduce the polarization fields in GaInN LEDs and the hotly debated efficiency droop, that is, the decreasing LED efficiency at high currents.

  8. A novel solid state photocatalyst for living radical polymerization under UV irradiation

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; McKenzie, Thomas G.; Ren, Jing M.; Tan, Shereen; Nam, Eunhyung; Qiao, Greg G.

    2016-02-01

    This study presents the development of a novel solid state photocatalyst for the photoinduced controlled radical polymerization of methacrylates under mild UV irradiation (λmax ≈ 365 nm) in the absence of conventional photoinitiators, metal-catalysts or dye sensitizers. The photocatalyst design was based on our previous finding that organic amines can act in a synergistic photochemical reaction with thiocarbonylthio compounds to afford well controlled polymethacrylates under UV irradiation. Therefore, in the current contribution an amine-rich polymer was covalently grafted onto a solid substrate, thus creating a heterogeneous catalyst that would allow for facile removal, recovery and recyclability when employed for such photopolymerization reactions. Importantly, the polymethacrylates synthesized using the solid state photocatalyst (ssPC) show similarly excellent chemical and structural integrity as those catalysed by free amines. Moreover, the ssPC could be readily recovered and re-used, with multiple cycles of polymerization showing minimal effect on the integrity of the catalyst. Finally, the ssPC was employed in various photo-“click” reactions, permitting high yielding conjugations under photochemical control.

  9. Solid-state supercapacitors with rationally designed heterogeneous electrodes fabricated by large area spray processing for wearable energy storage applications

    PubMed Central

    Huang, Chun; Zhang, Jin; Young, Neil P.; Snaith, Henry J.; Grant, Patrick S.

    2016-01-01

    Supercapacitors are in demand for short-term electrical charge and discharge applications. Unlike conventional supercapacitors, solid-state versions have no liquid electrolyte and do not require robust, rigid packaging for containment. Consequently they can be thinner, lighter and more flexible. However, solid-state supercapacitors suffer from lower power density and where new materials have been developed to improve performance, there remains a gap between promising laboratory results that usually require nano-structured materials and fine-scale processing approaches, and current manufacturing technology that operates at large scale. We demonstrate a new, scalable capability to produce discrete, multi-layered electrodes with a different material and/or morphology in each layer, and where each layer plays a different, critical role in enhancing the dynamics of charge/discharge. This layered structure allows efficient utilisation of each material and enables conservative use of hard-to-obtain materials. The layered electrode shows amongst the highest combinations of energy and power densities for solid-state supercapacitors. Our functional design and spray manufacturing approach to heterogeneous electrodes provide a new way forward for improved energy storage devices. PMID:27161379

  10. Tunable femtosecond lasers with low pump thresholds

    NASA Astrophysics Data System (ADS)

    Oppo, Karen

    The work in this thesis is concerned with the development of tunable, femtosecond laser systems, exhibiting low pump threshold powers. The main motive for this work was the development of a low threshold, self-modelocked Ti:Al2O3 laser in order to replace the conventional large-frame argon-ion pump laser with a more compact and efficient all-solid-state alternative. Results are also presented for an all-solid-state, self-modelocked Cr:LiSAF laser, however most of this work is concerned with self-modelocked Ti:Al2O3 laser systems. In chapter 2, the operation of a regeneratively-initiated, and a hard-aperture self- modelocked Ti:Al2O3 laser, pumped by an argon-ion laser, is discussed. Continuous- wave oscillation thresholds as low as 160mW have been demonstrated, along with self-modelocked threshold powers as low as 500mW. The measurement and suppression of phase noise on modelocked lasers is discussed in chapter 3. This is followed by a comparison of the phase noise characteristics of the regeneratively-initiated, and hard-aperture self-modelocked Ti:Al2O3 lasers. The use of a synchronously-operating, high resolution electron-optical streak camera in the evaluation of timing jitter is also presented. In chapter 4, the construction and self-modelocked operation of an all-solid-state Ti:Al2O3 laser is described. The all-solid-state alternative to the conventional argon-ion pump laser was a continuous-wave, intracavity-frequency doubled, diode-laser pumped Nd:YLF ring laser. At a total diode-laser pump power of 10W, this minilaser was capable of producing a single frequency output of 1W, at 523.5nm in a TEM00 beam. The remainder of this thesis looks at the operation of a self-modelocked Ti:Al2O3 laser generating ultrashort pulses at wavelengths as long as 1053nm. The motive for this work was the development of an all-solid-state, self- modelocked Ti:Al2O3 laser operating at 1053nm, for use as a master oscillator in a Nd:glass power chain.

  11. A comparative study of conventionally sintered and microwave sintered nickel zinc ferrite

    NASA Astrophysics Data System (ADS)

    Rani, Rekha; Juneja, J. K.; Raina, K. K.; Kotnala, R. K.; Prakash, Chandra

    2014-04-01

    For the present work, nickel zinc ferrite having compositional formula Ni0.8Zn0.2Fe2O4 was synthesized by conventional solid state method and sintered in conventional and microwave furnaces. Pellets were sintered with very short soaking time of 10 min at 1150 °C in microwave furnace whereas 4 hrs of soaking time was selected for conventional sintering at 1200 °C. Phase formation was confirmed by X-ray diffraction analysis technique. Scanning electron micrographs were taken for microstructural study. Dielectric properties were studied as a function of temperature. To study magnetic behavior, M-H hysteresis loops were recorded for both samples. It is observed that microwave sintered sample could obtain comparable properties to the conventionally sintered one in lesser soaking time at lower sintering temperature.

  12. Coatable Li4 SnS4 Solid Electrolytes Prepared from Aqueous Solutions for All-Solid-State Lithium-Ion Batteries.

    PubMed

    Choi, Young Eun; Park, Kern Ho; Kim, Dong Hyeon; Oh, Dae Yang; Kwak, Hi Ram; Lee, Young-Gi; Jung, Yoon Seok

    2017-06-22

    Bulk-type all-solid-state lithium-ion batteries (ASLBs) for large-scale energy-storage applications have emerged as a promising alternative to conventional lithium-ion batteries (LIBs) owing to their superior safety. However, the electrochemical performance of bulk-type ASLBs is critically limited by the low ionic conductivity of solid electrolytes (SEs) and poor ionic contact between the active materials and SEs. Herein, highly conductive (0.14 mS cm -1 ) and dry-air-stable SEs (Li 4 SnS 4 ) are reported, which are prepared using a scalable aqueous-solution process. An active material (LiCoO 2 ) coated by solidified Li 4 SnS 4 from aqueous solutions results in a significant improvement in the electrochemical performance of ASLBs. Side-effects of the exposure of LiCoO 2 to aqueous solutions are minimized by using predissolved Li 4 SnS 4 solution. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Preparation and electrochemical properties of Zr-site substituted Li7La3(Zr2-xMx)O12 (M = Ta, Nb) solid electrolytes

    NASA Astrophysics Data System (ADS)

    Huang, Mian; Shoji, Mao; Shen, Yang; Nan, Ce-Wen; Munakata, Hirokazu; Kanamura, Kiyoshi

    2014-09-01

    Li7La3Zr2O12 (LLZ) solid electrolytes with Zr site partially substituted by Ta and Nb elements were prepared via the conventional solid-state reaction. All the compositions could lead to the cubic garnet-type structure after sintering at 1150 °C. The use of γ-Al2O3 as a sintering aid in the preparation of doped LLZ was studied. It was shown that Al could help to improve the micro-structure for Nb doping, but not necessary for Ta doping. The Ta and Nb doping enhanced the ionic conductivity at 25 °C to 4.09 × 10-4 S cm-1 and 4.50 × 10-4 S cm-1, respectively. A conductivity as high as 1.23 × 10-3 S cm-1 was obtained when measured at 50 °C in air for the Nb-doped LLZ. All-solid-state batteries with LLZTa and LLZNb solid electrolytes were assembled and tested. The cyclic voltammetry (CV) measurement indicated the successful working of the batteries.

  14. Molecular Structure of Humin and Melanoidin via Solid State NMR

    PubMed Central

    Herzfeld, Judith; Rand, Danielle; Matsuki, Yoh; Daviso, Eugenio; Mak-Jurkauskas, Melody; Mamajanov, Irena

    2011-01-01

    Sugar-derived humins and melanoidins figure significantly in food chemistry, agricultural chemistry, biochemistry and prebiotic chemistry. Despite wide interest and significant experimental attention, the amorphous and insoluble nature of the polymers has made them resistant to conventional structural characterization. Here we make use of solid-state NMR methods, including selective 13C substitution, 1H-dephasing, and double quantum filtration. The spectra, and their interpretation, are simplified by relying exclusively on hydronium for catalysis. The results for polymers derived from ribose, deoxyribose and fructose indicate diverse pathways to furans, suggest a simple route to pyrroles in the presence of amines, and reveal a heterogenous network-type polymer in which sugar molecules cross-link the heterocycles. PMID:21456563

  15. Detection of X-ray photons by solution-processed organic-inorganic perovskites

    PubMed Central

    Yakunin, Sergii; Sytnyk, Mykhailo; Kriegner, Dominik; Shrestha, Shreetu; Richter, Moses; Matt, Gebhard J.; Azimi, Hamed; Brabec, Christoph J.; Stangl, Julian; Kovalenko, Maksym V.; Heiss, Wolfgang

    2017-01-01

    The evolution of real-time medical diagnostic tools such as angiography and computer tomography from radiography based on photographic plates was enabled by the development of integrated solid-state X-ray photon detectors, based on conventional solid-state semiconductors. Recently, for optoelectronic devices operating in the visible and near infrared spectral regions, solution-processed organic and inorganic semiconductors have also attracted immense attention. Here we demonstrate a possibility to use such inexpensive semiconductors for sensitive detection of X-ray photons by direct photon-to-current conversion. In particular, methylammonium lead iodide perovskite (CH3NH3PbI3) offers a compelling combination of fast photoresponse and a high absorption cross-section for X-rays, owing to the heavy Pb and I atoms. Solution processed photodiodes as well as photoconductors are presented, exhibiting high values of X-ray sensitivity (up to 25 µC mGyair-1 cm-3) and responsivity (1.9×104 carriers/photon), which are commensurate with those obtained by the current solid-state technology. PMID:28553368

  16. Design and performance of a vacuum-bottle solid-state calorimeter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bracken, D.S.; Biddle, R.; Cech, R.

    1997-11-01

    EG and G Mound Applied Technologies calorimetry personnel have developed a small, thermos-bottle solid-state calorimeter, which is now undergoing performance testing at Los Alamos National Laboratory. The thermos-bottle solid-state calorimeter is an evaluation prototype for characterizing the heat output of small heat standards and other homogeneous heat sources. The current maximum sample size is 3.5 in. long with a diameter of 0.8 in. The overall size of the thermos bottle and thermoelectric cooling device is 9.25 in. high by 3.75 in. diameter and less than 3 lb. Coupling this unit with compact electronics and a laptop computer makes this calorimetermore » easily hand carried by a single individual. This compactness was achieved by servo controlling the reference temperature below room temperature and replacing the water bath used in conventional calorimeter design with the thermos-bottle insulator. Other design features will also be discussed. The performance of the calorimeter will be presented.« less

  17. Conventional Physics can Explain Excess Heat in the Fleischmann-Pons Cold Fusion Effect

    NASA Astrophysics Data System (ADS)

    Chubb, Scott

    2011-03-01

    In 1989, when Fleischmann and Pons (FP) claimed they had created room temperature, nuclear fusion in a solid, a firestorm of controversy erupted. Beginning in 1991, the Office of Naval Research began a decade-long study of the FP excess heat effect. This effort documented the fact that the excess heat that FP observed is the result of a form of nuclear fusion that can occur in solids at reduced temperature, dynamically, through a deuteron (d)+d?helium-4 reaction, without high-energy particles or ? rays. This fact has been confirmed at SRI and at a number of other laboratories (most notably in the laboratory of Y. Arata, located at Osaka University, Japan). A key reason this fact has not been accepted is the lack of a cogent argument, based on fundamental physical ideas, justifying it. In the paper, this question is re-examined, based on a generalization of conventional energy band theory that applies to finite, periodic solids, in which d's are allowed to occupy wave-like, ion band states, similar to the kinds of states that electrons occupy in ordinary metals. Prior to being experimentally observed, the Ion Band State Theory of cold fusion predicted a potential d+d?helium-4 reaction, without high energy particles, would explain the excess heat, the helium-4 would be found in an unexpected place (outside heat- producing electrodes), and high-loading, x?1, in PdDx, would be required.

  18. Pennsylvania's technologically enhanced, naturally occurring radioactive material experiences and studies of the oil and gas industry.

    PubMed

    Allard, David J

    2015-02-01

    This presentation provides an overview of the Commonwealth of Pennsylvania's experiences and ongoing studies related to technologically enhanced, naturally occurring radioactive material (TENORM) in the oil and gas industry. It has been known for many years that Pennsylvania's geology is unique, with several areas having relatively high levels of natural uranium and thorium. In the 1950s, a few areas of the state were evaluated for commercial uranium production. In the late 1970s, scoping studies of radon in homes prompted the Pennsylvania Department of Environmental Protection (DEP) Bureau of Radiation Protection (BRP) to begin planning for a larger state-wide radon study. The BRP and Oil and Gas Bureau also performed a TENORM study of produced water in the early 1990s for a number of conventional oil and gas wells. More recently, BRP and the Bureau of Solid Waste developed radiation monitoring regulations for all Pennsylvania solid waste disposal facilities. These were implemented in 2001, prompting another evaluation of oil and gas operations and sludge generated from the treatment of conventionally produced water and brine but mainly focused on the disposal of TENORM solid waste in the state's Resource Conservation and Recovery Act Subtitle D landfills. However, since 2008, the increase in volumes of gas well wastewater and levels of Ra observed in the unconventional shale gas well flow-back fracking water has compelled DEP to fully re-examine these oil and gas operations. Specifically, with BRP in the lead, a new TENORM study of oil and gas operations and related wastewater treatment operations has been initiated (), supported by an American National Standards Institute standard on TENORM () and a U.S. Government Accountability Office report on shale resource development and risks (). This study began in early 2013 and will examine the potential public and worker radiation exposure and environmental impact as well as re-evaluate TENORM waste disposal. This presentation summarizes conventional and unconventional oil and gas well operations, geology and respective uranium/thorium content, radium content in oil and gas wastewater, treatment solids, radon in natural gas, the scope of other TENORM issues in the state, regulatory framework, national regulations and guidance. It also provides an overview of past and the status of ongoing TENORM studies in the Commonwealth (; Rowan and Kraemer 2012; ).

  19. Nano-Structured Solids and Heterogeneous Catalysts: Powerful Tools for the Reduction of CBRN Threats

    NASA Astrophysics Data System (ADS)

    Guidotti, M.; Rossodivita, A.; Ranghieri, M. C.

    In the field of non-conventional CBRN weapons, the recent rapid development of nanotechnology and catalysis over nanosized solids provides innovative tools for the detection, protection and decontamination against these threats. By improving the efficiency of the countermeasures and by minimizing the negative effects of a deliberate use of CBRN agents, the practical application of the new technologies will readily represent a step forward in lowering the vulnerability of the civilian populations and in preventing the use of mass destruction weapons by terrorist groups or by `rogue states' supporting terrorists' activity. In such scenario, some relevant examples of nanosystems applied to the defense from non-conventional warfare agents will be here presented and commented. The key role of nanotechnology and heterogeneous catalysis for a multidisciplinary approach in counteracting CBRN threats will be highlighted too.

  20. Nanostructures by ion beams

    NASA Astrophysics Data System (ADS)

    Schmidt, B.

    Ion beam techniques, including conventional broad beam ion implantation, ion beam synthesis and ion irradiation of thin layers, as well as local ion implantation with fine-focused ion beams have been applied in different fields of micro- and nanotechnology. The ion beam synthesis of nanoparticles in high-dose ion-implanted solids is explained as phase separation of nanostructures from a super-saturated solid state through precipitation and Ostwald ripening during subsequent thermal treatment of the ion-implanted samples. A special topic will be addressed to self-organization processes of nanoparticles during ion irradiation of flat and curved solid-state interfaces. As an example of silicon nanocrystal application, the fabrication of silicon nanocrystal non-volatile memories will be described. Finally, the fabrication possibilities of nanostructures, such as nanowires and chains of nanoparticles (e.g. CoSi2), by ion beam synthesis using a focused Co+ ion beam will be demonstrated and possible applications will be mentioned.

  1. The slab geometry laser. I - Theory

    NASA Technical Reports Server (NTRS)

    Eggleston, J. M.; Kane, T. J.; Kuhn, K.; Byer, R. L.; Unternahrer, J.

    1984-01-01

    Slab geometry solid-state lasers offer significant performance improvements over conventional rod-geometry lasers. A detailed theoretical description of the thermal, stress, and beam-propagation characteristics of a slab laser is presented. The analysis includes consideration of the effects of the zig-zag optical path, which eliminates thermal and stress focusing and reduces residual birefringence.

  2. Solid State Research.

    DTIC Science & Technology

    1984-05-15

    The chemistry of the conventional CVD of W films may be summarized by the overall reaction, WF 6 + 3 H2 - W + 6 HF (2-I) The activation energy for the...3 GATE VOLTAGE M Psum 3-1. Subdwedi obMaauls of n- &Md p-donnal SOIINOITs beforw de atar -vmdlmion. 30 - , ’_ 1 - - - - - -. .I Another effect of

  3. Simplified High-Power Inverter

    NASA Technical Reports Server (NTRS)

    Edwards, D. B.; Rippel, W. E.

    1984-01-01

    Solid-state inverter simplified by use of single gate-turnoff device (GTO) to commutate multiple silicon controlled rectifiers (SCR's). By eliminating conventional commutation circuitry, GTO reduces cost, size and weight. GTO commutation applicable to inverters of greater than 1-kilowatt capacity. Applications include emergency power, load leveling, drives for traction and stationary polyphase motors, and photovoltaic-power conditioning.

  4. Development of natural cellulase inhibitor mediated intensified biological pretreatment technology using Pleurotus florida for maximum recovery of cellulose from paddy straw under solid state condition.

    PubMed

    Naresh Kumar, Manickam; Ravikumar, Rajarathinam; Thenmozhi, Senniyappan; Kirupa Sankar, Muthuvelu

    2017-11-01

    Inhibitor mediated intensified bio-pretreatment (IMBP) technology using natural cellulase inhibitor (NCI) for maximum cellulose recovery from paddy straw was studied. Pretreatment was carried out under solid state condition. Supplementation of 8% NCI in pretreatment medium improves cellulose recovery and delignification by 1.2 and 1.5-fold respectively, compared to conventional bio-pretreatment due to inhibition of 61% of cellulase activity in IMBP. Further increase in NCI concentration showed negative effect on Pleurotus florida growth and suppress the laccase productivity by 1.1-fold. Laccase activity in IMBP was found to be 2.0U/mL on 19 th day, which is higher than (1.5U/mL) conventional bio-pretreatment. Physico-chemical modifications in paddy straw before and after pretreatment were analysed by SEM, ATR-FTIR, XRD and TGA. According to these findings, the IMBP technology can be a viable eco-friendly technology for sustainable production of bioethanol with maximum cellulose recovery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Performance analysis of three-dimensional-triple-level cell and two-dimensional-multi-level cell NAND flash hybrid solid-state drives

    NASA Astrophysics Data System (ADS)

    Sakaki, Yukiya; Yamada, Tomoaki; Matsui, Chihiro; Yamaga, Yusuke; Takeuchi, Ken

    2018-04-01

    In order to improve performance of solid-state drives (SSDs), hybrid SSDs have been proposed. Hybrid SSDs consist of more than two types of NAND flash memories or NAND flash memories and storage-class memories (SCMs). However, the cost of hybrid SSDs adopting SCMs is more expensive than that of NAND flash only SSDs because of the high bit cost of SCMs. This paper proposes unique hybrid SSDs with two-dimensional (2D) horizontal multi-level cell (MLC)/three-dimensional (3D) vertical triple-level cell (TLC) NAND flash memories to achieve higher cost-performance. The 2D-MLC/3D-TLC hybrid SSD achieves up to 31% higher performance than the conventional 2D-MLC/2D-TLC hybrid SSD. The factors of different performance between the proposed hybrid SSD and the conventional hybrid SSD are analyzed by changing its block size, read/write/erase latencies, and write unit of 3D-TLC NAND flash memory, by means of a transaction-level modeling simulator.

  6. High power diode lasers for solid-state laser pumps

    NASA Technical Reports Server (NTRS)

    Linden, Kurt J.; Mcdonnell, Patrick N.

    1994-01-01

    The development and commercial application of high power diode laser arrays for use as solid-state laser pumps is described. Such solid-state laser pumps are significantly more efficient and reliable than conventional flash-lamps. This paper describes the design and fabrication of diode lasers emitting in the 780 - 900 nm spectral region, and discusses their performance and reliability. Typical measured performance parameters include electrical-to-optical power conversion efficiencies of 50 percent, narrow-band spectral emission of 2 to 3 nm FWHM, pulsed output power levels of 50 watts/bar with reliability values of over 2 billion shots to date (tests to be terminated after 10 billion shots), and reliable operation to pulse lengths of 1 ms. Pulse lengths up to 5 ms have been demonstrated at derated power levels, and CW performance at various power levels has been evaluated in a 'bar-in-groove' laser package. These high-power 1-cm stacked-bar arrays are now being manufactured for OEM use. Individual diode laser bars, ready for package-mounting by OEM customers, are being sold as commodity items. Commercial and medical applications of these laser arrays include solid-state laser pumping for metal-working, cutting, industrial measurement and control, ranging, wind-shear/atmospheric turbulence detection, X-ray generation, materials surface cleaning, microsurgery, ophthalmology, dermatology, and dental procedures.

  7. Highly Conductive Solid-State Hybrid Electrolytes Operating at Subzero Temperatures.

    PubMed

    Kwon, Taeyoung; Choi, Ilyoung; Park, Moon Jeong

    2017-07-19

    We report a unique, highly conductive, dendrite-inhibited, solid-state polymer electrolyte platform that demonstrates excellent battery performance at subzero temperatures. A design based on functionalized inorganic nanoparticles with interconnected mesopores that contain surface nitrile groups is the key to this development. Solid-state hybrid polymer electrolytes based on succinonitrile (SN) electrolytes and porous nanoparticles were fabricated via a simple UV-curing process. SN electrolytes were effectively confined within the mesopores. This stimulated favorable interactions with lithium ions, reduced leakage of SN electrolytes over time, and improved mechanical strength of membranes. Inhibition of lithium dendrite growth and improved electrochemical stability up to 5.2 V were also demonstrated. The hybrid electrolytes exhibited high ionic conductivities of 2 × 10 -3 S cm -1 at room temperature and >10 -4 S cm -1 at subzero temperatures, leading to stable and improved battery performance at subzero temperatures. Li cells made with lithium titanate anodes exhibited stable discharge capacities of 151 mAh g -1 at temperatures below -10 °C. This corresponds to 92% of the capacity achieved at room temperature (164 mAh g -1 ). Our work represents a significant advance in solid-state polymer electrolyte technology and far exceeds the performance available with conventional polymeric battery separators.

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murgia, Fabrizio; Antitomaso, Philippe; Stievano, Lorenzo

    The ternary Chevrel phase Cu{sub 2}Mo{sub 6}S{sub 8} was successfully synthetized using a simple and cost-effective solid-state microwave-assisted reaction. While solid-state routes require days of high-temperature treatment under inert atmosphere, highly pure and crystalline Cu{sub 2}Mo{sub 6}S{sub 8} could be obtained in only 400 s from this precursor, the Chevrel binary phase Mo{sub 6}S{sub 8} was then obtained by copper removal through acidic leaching, and was evaluated as a positive electrode material for Mg-battery. The electrochemical performance in half-cell configuration shows reversible capacity exceeding 80 mAh/g, which is comparable to previous works carried out with materials synthesized by conventional high-temperaturemore » solid-state routes. - Graphical abstract: Ultrafast micro-wave synthesis of Chevrel phase Cu{sub 2}Mo{sub 6}S{sub 8} towards Mo{sub 6}S{sub 8} as positive electrode of Mg-battery. - Highlights: • Chevrel phase Cu{sub 2}Mo{sub 6}S{sub 8} is synthesized by fast microwave-assisted solid-state reaction. • Highly-pure and well-crystalline Cu{sub 2}Mo{sub 6}S{sub 8} is obtained. • Mo{sub 6}S{sub 8} obtained from leaching is tested as a positive electrode for Mg batteries.« less

  9. Solid-state NMR on bacterial cells: selective cell wall signal enhancement and resolution improvement using dynamic nuclear polarization.

    PubMed

    Takahashi, Hiroki; Ayala, Isabel; Bardet, Michel; De Paëpe, Gaël; Simorre, Jean-Pierre; Hediger, Sabine

    2013-04-03

    Dynamic nuclear polarization (DNP) enhanced solid-state nuclear magnetic resonance (NMR) has recently emerged as a powerful technique for the study of material surfaces. In this study, we demonstrate its potential to investigate cell surface in intact cells. Using Bacillus subtilis bacterial cells as an example, it is shown that the polarizing agent 1-(TEMPO-4-oxy)-3-(TEMPO-4-amino)propan-2-ol (TOTAPOL) has a strong binding affinity to cell wall polymers (peptidoglycan). This particular interaction is thoroughly investigated with a systematic study on extracted cell wall materials, disrupted cells, and entire cells, which proved that TOTAPOL is mainly accumulating in the cell wall. This property is used on one hand to selectively enhance or suppress cell wall signals by controlling radical concentrations and on the other hand to improve spectral resolution by means of a difference spectrum. Comparing DNP-enhanced and conventional solid-state NMR, an absolute sensitivity ratio of 24 was obtained on the entire cell sample. This important increase in sensitivity together with the possibility of enhancing specifically cell wall signals and improving resolution really opens new avenues for the use of DNP-enhanced solid-state NMR as an on-cell investigation tool.

  10. Effect of a commercial housing system on egg quality during extended storage.

    PubMed

    Jones, D R; Karcher, D M; Abdo, Z

    2014-05-01

    Egg producers in the United States are utilizing a variety of commercial egg production systems to provide consumer choice and meet legislative requirements. Consumer egg grades in the United States were developed for conventional cage production, and it is unclear what effect alternative production systems might have on egg quality during retail and consumer home storage. The current study was undertaken to determine what changes in egg quality characteristics occur during extended cold storage for commercially produced conventional cage, enriched colony cage, and cage-free aviary eggs. During 12 wk of cold storage, egg weight, albumen height, Haugh unit, static compression shell strength, vitelline membrane strength and deformation, yolk index, shell dynamic stiffness, and whole egg total solids were monitored. Overall, aviary and enriched eggs were significantly (P < 0.05) heavier than conventional cage. Albumen height and Haugh unit (P < 0.05) were significantly greater for conventional cage than enriched eggs. Static compression shell strength was greatest (P < 0.05) for enriched eggs compared with aviary. No overall housing system effects for yolk measurements, shell dynamic stiffness, or whole egg total solids were observed. Albumen height, Haugh unit, and yolk quality measurements were all greatest at 0 and lowest at 12 wk of storage (P < 0.05). The rate of quality change among the housing systems for each measured attribute at 4, 6, and 12 wk was determined. Other than differences in the change of egg weight at 4 wk, no significant differences in the rate of quality decline were found among the housing systems. The results of the current study indicate that current US egg quality standards should effectively define quality for commercially produced conventional cage, enriched colony cage, and cage-free aviary eggs.

  11. On the absence of reverse running waves in general displacement of lattice vibration in popular books on solid state theory

    NASA Astrophysics Data System (ADS)

    Xia, Shangda; Lou, Liren

    2018-05-01

    In this article we point out that there is a deficiency in the presentation of the general solution of harmonic lattice vibration, the omission of half of the allowed running waves, in many popular textbooks published since 1940, e.g. O Madelung’s 1978 Introduction to Solid-State Theory and J Solyom’s 2007 Fundamentals of the Physics of Solids, vol 1. So we provide a revised presentation, which gives a complete general solution and demonstrates clearly that the conventional complex normal coordinate should be a superposition of two coordinates (multiplied by a factor \\sqrt{1/2}) of running waves travelling oppositely along q and -q, not only a coordinate of a unidirectional running wave as many books considered. It is noticed that the book, Quantum Theory of the Solid State: An Introduction, by L Kantorovich, published in 2004, and the review article, ‘Phonons in perfect crystals’ by W Cochran and R A Cowly, published in 1967, for a one-dimensional single-atom chain gave correct (but not normalized) formulae for the general solution of lattice vibration and the normal coordinate. However, both of them stated still that each normal coordinate describes an independent mode of vibration, which in our opinion needs to be further discussed. Moreover, in books such as Fundamentals of the Physics of Solids, vol 1, by J Solyom, and The Physics and Chemistry of Solids, by S R Elliott, published in 2006 and 2007, respectively, the reverse waves were still lost. Hence, we also discuss a few related topics. In quantization of the lattice vibration, the introduction of the conventional two (not one) independent phonon operators in a normal coordinate is closely related to the ‘independence’ of the two constituent waves mentioned above, and we propose a simple propositional relation between the phonon operator and the corresponding running wave coordinate. Moreover, only the coordinate of the superposition wave (not the running wave), as the normal coordinate can give the correct quantization commutation relations. In addition, there is an interference between the direct and reverse running waves in kinetic and potential energies, which also questions the popular term ‘normal mode’ for a running wave mode. Therefore we have made a few suggestions and discuss the terms of relative quantities.

  12. Preliminary assessment for DNA extraction on microfluidic channel

    NASA Astrophysics Data System (ADS)

    Gopinath, Subash C. B.; Hashim, Uda; Uda, M. N. A.

    2017-03-01

    The aim of this research is to extract, purify and yield DNA in mushroom from solid state mushroom sample by using fabricated continuous high-capacity sample delivery microfluidic through integrated solid state extraction based amino-coated silica bead. This device is made to specifically extract DNA in mushroom sample in continuous inflow process with energy and cost consumption. In this project, we present two methods of DNA extraction and purification which are by using centrifuge (complex and conventional method) and by using microfluidic biosensor (new and fast method). DNA extracted can be determined by using ultraviolet-visible spectroscopy (UV-VIS). The peak obtained at wavelength 260nm after measuring the absorbance of sample proves that DNA is successfully extracted from the mushroom.

  13. Solid-state and fusion resistance spot welding of TD-NiCr sheet

    NASA Technical Reports Server (NTRS)

    Moore, T. J.

    1973-01-01

    By using specially processed TD-NiCr sheet in both 0.4-mm (0.015-in.) and 1.6-mm (0.062-in.) thicknesses and carefully selected welding procedures, solid state resistance spot welds were produced which, after postheating at 1200 C, were indistinguishable from the parent material. Stress-rupture shear tests of single-spot lap joints in 0.4-mm (0.015-in.) thick sheet showed that these welds were as strong as the parent material. Similar results were obtained in tensile-shear tests at room temperature and 1100 C and in fatigue tests. Conventional fusion spot welds in commercial sheet were unsatisfactory because of poor stress-rupture shear properties resulting from metallurgical damage to the parent material.

  14. An automatic analyzer of solid state nuclear track detectors using an optic RAM as image sensor

    NASA Astrophysics Data System (ADS)

    Staderini, Enrico Maria; Castellano, Alfredo

    1986-02-01

    An optic RAM is a conventional digital random access read/write dynamic memory device featuring a quartz windowed package and memory cells regularly ordered on the chip. Such a device is used as an image sensor because each cell retains data stored in it for a time depending on the intensity of the light incident on the cell itself. The authors have developed a system which uses an optic RAM to acquire and digitize images from electrochemically etched CR39 solid state nuclear track detectors (SSNTD) in the track count rate up to 5000 cm -2. On the digital image so obtained, a microprocessor, with appropriate software, performs image analysis, filtering, tracks counting and evaluation.

  15. Fusion processing of itraconazole solid dispersions by kinetisol dispersing: a comparative study to hot melt extrusion.

    PubMed

    DiNunzio, James C; Brough, Chris; Miller, Dave A; Williams, Robert O; McGinity, James W

    2010-03-01

    KinetiSol Dispersing (KSD) is a novel high energy manufacturing process investigated here for the production of pharmaceutical solid dispersions. Solid dispersions of itraconazole (ITZ) and hypromellose were produced by KSD and compared to identical formulations produced by hot melt extrusion (HME). Materials were characterized for solid state properties by modulated differential scanning calorimetry and X-ray diffraction. Dissolution behavior was studied under supersaturated conditions. Oral bioavailability was determined using a Sprague-Dawley rat model. Results showed that KSD was able to produce amorphous solid dispersions in under 15 s while production by HME required over 300 s. Dispersions produced by KSD exhibited single phase solid state behavior indicated by a single glass transition temperature (T(g)) whereas compositions produced by HME exhibited two T(g)s. Increased dissolution rates for compositions manufactured by KSD were also observed compared to HME processed material. Near complete supersaturation was observed for solid dispersions produced by either manufacturing processes. Oral bioavailability from both processes showed enhanced AUC compared to crystalline ITZ. Based on the results presented from this study, KSD was shown to be a viable manufacturing process for the production of pharmaceutical solid dispersions, providing benefits over conventional techniques including: enhanced mixing for improved homogeneity and reduced processing times. 2009 Wiley-Liss, Inc. and the American Pharmacists Association

  16. A novel monodisperse SiO2@C-dot for the rapid and facile identification of latent fingermarks using self-quenching resistant solid-state fluorescence.

    PubMed

    Peng, Di; Liu, Xiang; Huang, Mengjun; Wang, Dan; Liu, Renlong

    2018-04-24

    Solid powder fluorescence shows great potential for application in medicine, biology, and engineering, especially in the identification of latent fingermarks in forensic science. However, conventional developing methods suffer from some drawbacks, such as low contrast, low sensitivity, low selectivity, and high toxicity. To conquer these challenges, novel SiO2@C-dot microspheres were prepared via a facile one-pot hydrothermal method by using citric acid as a carbon source and aminosilane as a nitrogen source. Interestingly, the results showed that the resultant powders possess good monodispersity, high fluorescence emission, and resistance to self-quenching. Additionally, the mechanism for the solid-state fluorescence of SiO2@C-dot compounds was also investigated. More importantly, the fingermarks on various surfaces, including transparent glasses, ceramic tiles, transparent plastics, aluminum alloys, plastic cards, painted woods, artificial leathers, and Chinese paper money, developed by the powders have indicated well-defined papillary ridges under a 365 nm UV lamp. The novel strategy of using monodisperse SiO2@C-dot microspheres as a fluorescent label for developing latent fingermarks showed greater advantages compared to conventional methods, which was also demonstrated using the automatic fingerprint identification system. It is simple, rapid, low-cost, nontoxic, and effective, and is expected to be a promising alternative for the development of latent fingerprints in forensic science.

  17. Characterization of manure from conventional and phytase transgenic pigs by advanced solid-state NMR spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Non-point phosphorus (P) pollution from animal manure is becoming a serious global problem. The current solution for the swine industry is including the enzyme phytase as a component of the cereal grain diet. A very real possibility in the future is the production of transgenic pigs that express phy...

  18. Molten salt synthesis of nanocrystalline phase of high dielectric constant material CaCu3Ti4O12.

    PubMed

    Prakash, B Shri; Varma, K B R

    2008-11-01

    Nanocrystalline powders of giant dielectric constant material, CaCu3Ti4O12 (CCTO), have been prepared successfully by the molten salt synthesis (MSS) using KCl at 750 degrees C/10 h, which is significantly lower than the calcination temperature (approximately 1000 degrees C) that is employed to obtain phase pure CCTO in the conventional solid-state reaction route. The water washed molten salt synthesized powder, characterized by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), and Transmission electron microscopy (TEM) confirmed to be a phase pure CCTO associated with approximately 150 nm sized crystallites of nearly spherical shape. The decrease in the formation temperature/duration of CCTO in MSS method was attributed to an increase in the diffusion rate or a decrease in the diffusion length of reacting ions in the molten salt medium. As a consequence of liquid phase sintering, pellets of as-synthesized KCl containing CCTO powder exhibited higher sinterability and grain size than that of KCl free CCTO samples prepared by both MSS method and conventional solid-state reaction route. The grain size and the dielectric constant of KCl containing CCTO ceramics increased with increasing sintering temperature (900 degrees C-1050 degrees C). Indeed the dielectric constants of these ceramics were higher than that of KCl free CCTO samples prepared by both MSS method and those obtained via the solid-state reaction route and sintered at the same temperature. Internal barrier layer capacitance (IBLC) model was invoked to correlate the observed dielectric constant with the grain size in these samples.

  19. Energy issues in microwave food processing: A review of developments and the enabling potentials of solid-state power delivery.

    PubMed

    Atuonwu, J C; Tassou, S A

    2018-01-23

    The enormous magnitude and variety of microwave applications in household, commercial and industrial food processing creates a strong motivation for improving the energy efficiency and hence, sustainability of the process. This review critically assesses key energy issues associated with microwave food processing, focusing on previous energy performance studies, energy performance metrics, standards and regulations. Factors affecting energy-efficiency are categorised into source, load and source-load matching factors. This highlights the need for highly-flexible and controllable power sources capable of receiving real-time feedback on load properties, and effecting rapid control actions to minimise reflections, heating non-uniformities and other imperfections that lead to energy losses. A case is made for the use of solid-state amplifiers as alternatives to conventional power sources, magnetrons. By a full-scale techno-economic analysis, including energy aspects, it is shown that the use of solid-state amplifiers as replacements to magnetrons is promising, not only from an energy and overall technical perspective, but also in terms of economics.

  20. Toward practical all-solid-state lithium-ion batteries with high energy density and safety: Comparative study for electrodes fabricated by dry- and slurry-mixing processes

    NASA Astrophysics Data System (ADS)

    Nam, Young Jin; Oh, Dae Yang; Jung, Sung Hoo; Jung, Yoon Seok

    2018-01-01

    Owing to their potential for greater safety, higher energy density, and scalable fabrication, bulk-type all-solid-state lithium-ion batteries (ASLBs) employing deformable sulfide superionic conductors are considered highly promising for applications in battery electric vehicles. While fabrication of sheet-type electrodes is imperative from the practical point of view, reports on relevant research are scarce. This might be attributable to issues that complicate the slurry-based fabrication process and/or issues with ionic contacts and percolation. In this work, we systematically investigate the electrochemical performance of conventional dry-mixed electrodes and wet-slurry fabricated electrodes for ASLBs, by varying the different fractions of solid electrolytes and the mass loading. This information calls for a need to develop well-designed electrodes with better ionic contacts and to improve the ionic conductivity of solid electrolytes. As a scalable proof-of-concept to achieve better ionic contacts, a premixing process for active materials and solid electrolytes is demonstrated to significantly improve electrochemical performance. Pouch-type 80 × 60 mm2 all-solid-state LiNi0·6Co0·2Mn0·2O2/graphite full-cells fabricated by the slurry process show high cell-based energy density (184 W h kg-1 and 432 W h L-1). For the first time, their excellent safety is also demonstrated by simple tests (cutting with scissors and heating at 110 °C).

  1. Crosslinked hydrogels-a promising class of insoluble solid molecular dispersion carriers for enhancing the delivery of poorly soluble drugs.

    PubMed

    Sun, Dajun D; Lee, Ping I

    2014-02-01

    Water-insoluble materials containing amorphous solid dispersions (ASD) are an emerging category of drug carriers which can effectively improve dissolution kinetics and kinetic solubility of poorly soluble drugs. ASDs based on water-insoluble crosslinked hydrogels have unique features in contrast to those based on conventional water-soluble and water-insoluble carriers. For example, solid molecular dispersions of poorly soluble drugs in poly(2-hydroxyethyl methacrylate) (PHEMA) can maintain a high level of supersaturation over a prolonged period of time via a feedback-controlled diffusion mechanism thus avoiding the initial surge of supersaturation followed by a sharp decline in drug concentration typically encountered with ASDs based on water-soluble polymers. The creation of both immediate- and controlled-release ASD dosage forms is also achievable with the PHEMA based hydrogels. So far, ASD systems based on glassy PHEMA have been shown to be very effective in retarding precipitation of amorphous drugs in the solid state to achieve a robust physical stability. This review summarizes recent research efforts in investigating the potential of developing crosslinked PHEMA hydrogels as a promising alternative to conventional water-soluble ASD carriers, and a related finding that the rate of supersaturation generation does affect the kinetic solubility profiles implications to hydrogel based ASDs.

  2. Crosslinked hydrogels—a promising class of insoluble solid molecular dispersion carriers for enhancing the delivery of poorly soluble drugs

    PubMed Central

    Sun, Dajun D.; Lee, Ping I.

    2014-01-01

    Water-insoluble materials containing amorphous solid dispersions (ASD) are an emerging category of drug carriers which can effectively improve dissolution kinetics and kinetic solubility of poorly soluble drugs. ASDs based on water-insoluble crosslinked hydrogels have unique features in contrast to those based on conventional water-soluble and water-insoluble carriers. For example, solid molecular dispersions of poorly soluble drugs in poly(2-hydroxyethyl methacrylate) (PHEMA) can maintain a high level of supersaturation over a prolonged period of time via a feedback-controlled diffusion mechanism thus avoiding the initial surge of supersaturation followed by a sharp decline in drug concentration typically encountered with ASDs based on water-soluble polymers. The creation of both immediate- and controlled-release ASD dosage forms is also achievable with the PHEMA based hydrogels. So far, ASD systems based on glassy PHEMA have been shown to be very effective in retarding precipitation of amorphous drugs in the solid state to achieve a robust physical stability. This review summarizes recent research efforts in investigating the potential of developing crosslinked PHEMA hydrogels as a promising alternative to conventional water-soluble ASD carriers, and a related finding that the rate of supersaturation generation does affect the kinetic solubility profiles implications to hydrogel based ASDs. PMID:26579361

  3. Investigation on the interface between Li10GeP2S12 electrolyte and carbon conductive agents in all-solid-state lithium battery.

    PubMed

    Yoon, Kyungho; Kim, Jung-Joon; Seong, Won Mo; Lee, Myeong Hwan; Kang, Kisuk

    2018-05-23

    All-solid-state batteries are considered as one of the attractive alternatives to conventional lithium-ion batteries, due to their intrinsic safe properties benefiting from the use of non-flammable solid electrolytes in ASSBs. However, one of the issues in employing the solid-state electrolyte is the sluggish ion transport kinetics arising from the chemical and physical instability of the interfaces among solid components including electrode material, electrolyte and additive agents. In this work, we investigate the stability of the interface between carbon conductive agents and Li 10 GeP 2 S 12 in a composite cathode and its effect on the electrochemical performance of ASSBs. It is found that the inclusion of various carbon conductive agents in composite cathode leads to inferior kinetic performance of the cathode despite expectedly enhanced electrical conductivity of the composite. We observe that the poor kinetic performance is attributed to a large interfacial impedance which is gradually developed upon the inclusions of the various carbon conductive agents regardless of their physical differences. The analysis through X-ray Photoelectron Spectroscopy suggests that the carbon additives in the composite cathode stimulate the electrochemical decomposition of LGPS electrolyte degrading its surface during cycling, indicating the large interfacial resistance stems from the undesirable decomposition of the electrolyte at the interface.

  4. Irinotecan-loaded double-reversible thermogel with improved antitumor efficacy without initial burst effect and toxicity for intramuscular administration.

    PubMed

    Din, Fakhar Ud; Kim, Dong Wuk; Choi, Ju Yeon; Thapa, Raj Kumar; Mustapha, Omer; Kim, Dong Shik; Oh, Yu-Kyoung; Ku, Sae Kwang; Youn, Yu Seok; Oh, Kyung Taek; Yong, Chul Soon; Kim, Jong Oh; Choi, Han-Gon

    2017-05-01

    Intramuscularly administered, anti-tumour drugs induce severe side effects due to their direct contact with body tissues and initial burst effect. In this study, to solve this problem, a novel double-reversible thermogel system (DRTG) for the intramuscular administration of irinotecan was developed. This irinotecan-loaded DRTG was prepared by dispersing the irinotecan-loaded thermoreversible solid lipid nanoparticles (SLNs) in the thermoreversible hydrogel. In DRTG, the former was solid at 25°C but converted to liquid at 36.5°C; in contrast, the latter existed in a liquid form but transformed to gel state in the body. The DRTG was easily administered intramuscularly. Its particle size and drug content were not noticeably changeable, resulting that it was stable at 40°C for at least 6months. Compared to the irinotecan-loaded solution and conventional hydrogel, the DRTG significantly delayed drug release, leading to a reduced burst effect. Moreover, it showed decreased C max and maintained the sustained plasma concentrations at a relatively low level for the long period of 60h in rats, resulting in ameliorated side effects of the anti-tumour drug. Furthermore, it gave significantly improved anti-tumour efficacy in tumour-bearing mice compared to the hydrogel but, unlike the conventional hydrogel, induced no body weight loss and local damage to the muscle. Thus, this DRTG with improved antitumor efficacy without initial burst effect and toxicity could provide a potential pharmaceutical system for the intramuscular administration of irinotecan. Intramuscularly administered, anti-tumour drugs induce severe side effects due to their direct contact with body tissues and initial burst effect. To solve this problem, we developed a novel double-reversible thermogel system (DRTG) for the intramuscular administration of irinotecan. Unlike the conventional hydrogel, the DRTG is a dispersion of the irinotecan-loaded thermoreversible solid lipid nanoparticles in the thermoreversible hydrogel. In DRTG, the former was solid at 25°C but converted to liquid at 36.5°C; in contrast, the latter existed in a liquid form but transformed to gel state in the body. This DRTG gave significantly improved anti-tumour efficacy in tumour-bearing mice compared to the hydrogel but, unlike the conventional hydrogel, induced no body weight loss and local damage to the muscle. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  5. Simultaneous dual-radionuclide myocardial perfusion imaging with a solid-state dedicated cardiac camera.

    PubMed

    Ben-Haim, Simona; Kacperski, Krzysztof; Hain, Sharon; Van Gramberg, Dean; Hutton, Brian F; Erlandsson, Kjell; Sharir, Tali; Roth, Nathaniel; Waddington, Wendy A; Berman, Daniel S; Ell, Peter J

    2010-08-01

    We compared simultaneous dual-radionuclide (DR) stress and rest myocardial perfusion imaging (MPI) with a novel solid-state cardiac camera and a conventional SPECT camera with separate stress and rest acquisitions. Of 27 consecutive patients recruited, 24 (64.5+/-11.8 years of age, 16 men) were injected with 74 MBq of (201)Tl (rest) and 250 MBq (99m)Tc-MIBI (stress). Conventional MPI acquisition times for stress and rest are 21 min and 16 min, respectively. Rest (201)Tl for 6 min and simultaneous DR 15-min list mode gated scans were performed on a D-SPECT cardiac scanner. In 11 patients DR D-SPECT was performed first and in 13 patients conventional stress (99m)Tc-MIBI SPECT imaging was performed followed by DR D-SPECT. The DR D-SPECT data were processed using a spill-over and scatter correction method. DR D-SPECT images were compared with rest (201)Tl D-SPECT and with conventional SPECT images by visual analysis employing the 17-segment model and a five-point scale (0 normal, 4 absent) to calculate the summed stress and rest scores. Image quality was assessed on a four-point scale (1 poor, 4 very good) and gut activity was assessed on a four-point scale (0 none, 3 high). Conventional MPI studies were abnormal at stress in 17 patients and at rest in 9 patients. In the 17 abnormal stress studies DR D-SPECT MPI showed 113 abnormal segments and conventional MPI showed 93 abnormal segments. In the nine abnormal rest studies DR D-SPECT showed 45 abnormal segments and conventional MPI showed 48 abnormal segments. The summed stress and rest scores on conventional SPECT and DR D-SPECT were highly correlated (r=0.9790 and 0.9694, respectively). The summed scores of rest (201)Tl D-SPECT and DR-DSPECT were also highly correlated (r=0.9968, p<0.0001 for all). In six patients stress perfusion defects were significantly larger on stress DR D-SPECT images, and five of these patients were imaged earlier by D-SPECT than by conventional SPECT. Fast and high-quality simultaneous DR MPI is feasible with D-SPECT in a single imaging session with comparable diagnostic performance and image quality to conventional SPECT and to a separate rest (201)Tl D-SPECT acquisition.

  6. Ionic-Liquid-Based Polymer Electrolytes for Battery Applications.

    PubMed

    Osada, Irene; de Vries, Henrik; Scrosati, Bruno; Passerini, Stefano

    2016-01-11

    The advent of solid-state polymer electrolytes for application in lithium batteries took place more than four decades ago when the ability of polyethylene oxide (PEO) to dissolve suitable lithium salts was demonstrated. Since then, many modifications of this basic system have been proposed and tested, involving the addition of conventional, carbonate-based electrolytes, low molecular weight polymers, ceramic fillers, and others. This Review focuses on ternary polymer electrolytes, that is, ion-conducting systems consisting of a polymer incorporating two salts, one bearing the lithium cation and the other introducing additional anions capable of plasticizing the polymer chains. Assessing the state of the research field of solid-state, ternary polymer electrolytes, while giving background on the whole field of polymer electrolytes, this Review is expected to stimulate new thoughts and ideas on the challenges and opportunities of lithium-metal batteries. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Magneto-ionic control of interfacial magnetism

    NASA Astrophysics Data System (ADS)

    Bauer, Uwe; Yao, Lide; Tan, Aik Jun; Agrawal, Parnika; Emori, Satoru; Tuller, Harry L.; van Dijken, Sebastiaan; Beach, Geoffrey S. D.

    2015-02-01

    In metal/oxide heterostructures, rich chemical, electronic, magnetic and mechanical properties can emerge from interfacial chemistry and structure. The possibility to dynamically control interface characteristics with an electric field paves the way towards voltage control of these properties in solid-state devices. Here, we show that electrical switching of the interfacial oxidation state allows for voltage control of magnetic properties to an extent never before achieved through conventional magneto-electric coupling mechanisms. We directly observe in situ voltage-driven O2- migration in a Co/metal-oxide bilayer, which we use to toggle the interfacial magnetic anisotropy energy by >0.75 erg cm-2 at just 2 V. We exploit the thermally activated nature of ion migration to markedly increase the switching efficiency and to demonstrate reversible patterning of magnetic properties through local activation of ionic migration. These results suggest a path towards voltage-programmable materials based on solid-state switching of interface oxygen chemistry.

  8. Sensitizing solid state nuclear magnetic resonance of dilute nuclei by spin-diffusion assisted polarization transfers.

    PubMed

    Lupulescu, Adonis; Frydman, Lucio

    2011-10-07

    Recent years have witnessed efforts geared at increasing the sensitivity of NMR experiments, by relying on the suitable tailoring and exploitation of relaxation phenomena. These efforts have included the use of paramagnetic agents, enhanced (1)H-(1)H incoherent and coherent transfers processes in 2D liquid state spectroscopy, and homonuclear (13)C-(13)C spin diffusion effects in labeled solids. The present study examines some of the opportunities that could open when exploiting spontaneous (1)H-(1)H spin-diffusion processes, to enhance relaxation and to improve the sensitivity of dilute nuclei in solid state NMR measurements. It is shown that polarization transfer experiments executed under sufficiently fast magic-angle-spinning conditions, enable a selective polarization of the dilute low-γ spins by their immediate neighboring protons. Repolarization of the latter can then occur during the time involved in monitoring the signal emitted by the low-γ nuclei. The basic features involved in the resulting approach, and its potential to improve the effective sensitivity of solid state NMR measurements on dilute nuclei, are analyzed. Experimental tests witness the advantages that could reside from utilizing this kind of approach over conventional cross-polarization processes. These measurements also highlight a number of limitations that will have to be overcome for transforming selective polarization transfers of this kind into analytical methods of choice. © 2011 American Institute of Physics

  9. Characterization of biomass waste torrefaction under conventional and microwave heating.

    PubMed

    Ho, Shih-Hsin; Zhang, Congyu; Chen, Wei-Hsin; Shen, Ying; Chang, Jo-Shu

    2018-05-13

    To evaluate the potential of microwave heating for biomass torrefaction, the torrefaction performances and energy utilization of coffee grounds and microalga residue, under conventional and microwave heating were investigated and compared with each other. For the two biomass samples, the dehydrogenation of the coffee grounds was more sensitive to torrefaction severity, whereas the microalga residue consumed more energy under the same torrefaction conditions. Microwave heating under lower torrefaction severity had a higher energy efficiency. As regard to the lower solid yields or higher torrefaction severity, the energy efficiency of microwave heating was close to that of conventional heating, irrespective of the feedstocks. This revealed the comparable energy consumption state between the two heating modes. Accordingly, it is concluded that microwave torrefaction is more efficient for biomass upgrading and densification than conventional torrefaction. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Solid-state supercapacitors with ionic liquid gel polymer electrolyte based on poly (3, 4-ethylenedioxythiophene), carbon nanotubes, and metal oxides nanocomposites for electrical energy storage

    NASA Astrophysics Data System (ADS)

    Obeidat, Amr M.

    Clean and renewable energy systems have emerged as an important area of research having diverse and significant new applications. These systems utilize different energy storage methods such as the batteries and supercapacitors. Supercapacitors are electrochemical energy storage devices that are designed to bridge the gap between batteries and conventional capacitors. Supercapacitors which store electrical energy by electrical double layer capacitance are based on large surface area structured carbons. The materials systems in which the Faradaic reversible redox reactions store electrical energy are the transition metal oxides and electronically conducting polymers. Among the different types of conducting polymers, poly (3, 4- ethylenedioxythiophene) (PEDOT) is extensively investigated owing to its chemical and mechanical stability. Due to instability of aqueous electrolytes at high voltages and toxicity of organic electrolytes, potential of supercapacitors has not been fully exploited. A novel aspect of this work is in utilizing the ionic liquid gel polymer electrolyte to design solid-state supercapacitors for energy storage. Various electrochemical systems were investigated including graphene, PEDOT, PEDOT-carbon nanotubes, PEDOT-manganese oxide, and PEDOT-iron oxide nanocomposites. The electrochemical performance of solid-state supercapacitor devices was evaluated based on cyclic voltammetry (CV), charge-discharge (CD), prolonged cyclic tests, and electrochemical impedance spectroscopy (EIS) techniques. Raman spectroscopy technique was also utilized to analyze the bonding structure of the electrode materials. The graphene solid-state supercapacitor system displayed areal capacitance density of 141.83 mF cm-2 based on high potential window up to 4V. The PEDOT solid-state supercapacitor system was synthesized in acetonitrile and aqueous mediums achieving areal capacitance density of 219.17 mF cm-2. The hybrid structure of solid-state supercapacitors was also studied in solid-state design based on PEDOT and graphene electrodes that produced areal capacitance density of 198.26 mF cm-2. Symmetrical PEDOT-manganese oxide nanocomposites were synthesized by co-deposition and dip-coating techniques to fabricate solid-state supercapacitor systems achieving areal capacitance density of 122.08 mF cm-2 credited to the PEDOT-MnO2 supercapacitor that was synthesized by dipping the PEDOT electrode in pure KMnO4 solution. The electrochemical performance of PEDOT-carbon nanotube solid-state supercapacitors was also investigated in both acetonitrile and aqueous medium showing good dispersion characteristics with optimum CNT content of 1 mg. The PEDOT-CNT solid-state supercapacitor system synthesized in acetonitrile displayed areal capacitance density of 297.43 mF cm-2. PEDOT-Fe2O3 nanocomposites were synthesized by single-step co-deposition techniques, and these were used to fabricate solid-state supercapacitors achieving areal capacitance density of 96.89 mF cm-2. Furthermore, some of these thin flexible solid-state supercapacitors were integrated with solar cells for direct storage of solar electricity, which proved to be promising as autonomous power source for flexible and wearable electronics. This dissertation describes the electrode synthesis, design and properties of solid-state supercapacitors, and their electrochemical performance in the storage of electrical energy.

  11. On the application of CaF2:Eu and SrF2:Eu phosphors in LED based phototherapy lamp

    NASA Astrophysics Data System (ADS)

    Belsare, P. D.; Moharil, S. V.; Joshi, C. P.; Omanwar, S. K.

    2013-06-01

    In the last few years the interest of scientific community has been increased towards solid state lighting based on LEDs because of their superior advantages over the conventional fluorescent lamps. As the GaN based LEDs are easily available efforts of the researchers are now on making the new phosphors which are excitable in the near UV region (360-400nm) for solid state lighting. This paper reports the photoluminescence characteristics of CaF2:Eu and SrF2:Eu phosphor prepared by wet chemical method. The violet emission of these phosphors with near UV excitation can be useful in making a phototherapy lamp based on LEDs for treating various skin diseases like acne vulgaris and hyperbilirubinemia.

  12. Ionic Salt Effect on the Phase Transition of PS-b-P2VP Copolymers

    NASA Astrophysics Data System (ADS)

    Kim, Bokyung; An, Hyungju; Ryu, Du Yeol; Kim, Jehan

    2009-03-01

    Solid-state electrolytes have long been considered as suitable candidates owing to the simple and easy processes for rechargeable battery manufactures, compared to conventional liquid electrolyte counterparts. Especially, polymer/salt systems involving PMMA and PVP complex forms have been studied since they provide stable electrochemical characteristics as well as mechanical properties. We studied the phase behavior of PS-b-P2VP upon the salt addition by small angle x-ray scattering (SAXS) and depolarized light scattering. Transition temperatures of block copolymer were significantly influenced by the salt addition in addition to the changes of d-spacings, which is caused by the effective coordinative interaction between P2VP block and salt. This study suggests a simple approach to solid-state block copolymer electrolytes.

  13. Process for making dense thin films

    DOEpatents

    Jacobson, Craig P.; Visco, Steven J.; DeJonghe, Lutgard C.

    2005-07-26

    Provided are low-cost, mechanically strong, highly electronically conductive porous substrates and associated structures for solid-state electrochemical devices, techniques for forming these structures, and devices incorporating the structures. The invention provides solid state electrochemical device substrates of novel composition and techniques for forming thin electrode/membrane/electrolyte coatings on the novel or more conventional substrates. In particular, in one embodiment the invention provides techniques for firing of device substrate to form densified electrolyte/membrane films 5 to 20 microns thick. In another embodiment, densified electrolyte/membrane films 5 to 20 microns thick may be formed on a pre-sintered substrate by a constrained sintering process. In some cases, the substrate may be a porous metal, alloy, or non-nickel cermet incorporating one or more of the transition metals Cr, Fe, Cu and Ag, or alloys thereof.

  14. Elucidation of Free Radical and Optogalvanic Spectroscopy Associated with Microgravity Combustion via Conventional and Novel Laser Platforms

    NASA Technical Reports Server (NTRS)

    Misra, Prabhakar; She, Yong-Bo; Zhu, Xin-Ming; King, Michael

    1997-01-01

    Combustion studies under both normal gravity and microgravity conditions depend a great deal on the availability and quality of the diagnostic systems used for such investigations. Microgravity phenomena are specially susceptible to even small perturbations and therefore non-intrusive diagnostic techniques are of paramount importance for successful understanding of reduced-gravity combustion phenomena. Several non-intrusive diagnostic techniques are available for probing and delineating normal as well as reduced gravity combustion processes, such as Rayleigh scattering, Raman scattering, Mie scattering, velocimetry, interferometric and Schlieren techniques, emission and laser-induced fluorescence (LIF) spectroscopy. Our approach is to use the LIF technique as a non-intrusive diagnostic tool for the study of combustion-associated free radicals and use the concomitant optogalvanic transitions to accomplish precise calibration of the laser wavelengths used for recording the excitation spectra of transient molecular species. In attempting to perform spectroscopic measurements on chemical intermediates, we have used conventional laser sources as well as new and novel platforms employing rare-earth doped solid-state lasers. Conventional (commercially available) sources of tunable UV laser radiation are extremely cumbersome and energy-consuming devices that are not very suitable for either in-space or in-flight (or microgravity drop tower) experiments. Traditional LIF sources of tunable UV laser radiation involve in addition to a pump laser (usually a Nd:YAG laser with an attached frequency-doubling stage), a tunable dye laser. In turn, the dye laser has to be provided with a dye circulation system and a subsequent stage for frequency-doubling of the dye laser radiation, together with a servo-tuning system (termed the 'Autotracker') to follow the wavelength changes and also an optical system (called the 'Frequency Separator') for separation of the emanating visible and UV beams. In contrast to this approach, we have devised an alternate arrangement for recording LIF excitation spectra of free radicals (following appropriate precursor fragmentation) that utilizes a tunable rare-earth doped solid state laser system with direct UV pumping. We have designed a compact and portable tunable UV laser system incorporating features necessary for both in-space and in-flight spectroscopy experiments. For the purpose of LIF excitation, we have developed an all-solid-state tunable UV laser that employs direct pumping of the solid-state UV-active medium employing UV harmonics from a Nd:YAG laser. An optical scheme with counterpropagating photolysis and excitation beams focused by suitable lenses into a reaction vacuum chamber was employed.

  15. Novel Li[(CF3SO2)(n-C4F9SO2)N]-Based Polymer Electrolytes for Solid-State Lithium Batteries with Superior Electrochemical Performance.

    PubMed

    Ma, Qiang; Qi, Xingguo; Tong, Bo; Zheng, Yuheng; Feng, Wenfang; Nie, Jin; Hu, Yong-Sheng; Li, Hong; Huang, Xuejie; Chen, Liquan; Zhou, Zhibin

    2016-11-02

    Solid polymer electrolytes (SPEs) would be promising candidates for application in high-energy rechargeable lithium (Li) batteries to replace the conventional organic liquid electrolytes, in terms of the enhanced safety and excellent design flexibility. Herein, we first report novel perfluorinated sulfonimide salt-based SPEs, composed of lithium (trifluoromethanesulfonyl)(n-nonafluorobutanesulfonyl)imide (Li[(CF 3 SO 2 )(n-C 4 F 9 SO 2 )N], LiTNFSI) and poly(ethylene oxide) (PEO), which exhibit relatively efficient ionic conductivity (e.g., 1.04 × 10 -4 S cm -1 at 60 °C and 3.69 × 10 -4 S cm -1 at 90 °C) and enough thermal stability (>350 °C), for rechargeable Li batteries. More importantly, the LiTNFSI-based SPEs could not only deliver the excellent interfacial compatibility with electrodes (e.g., Li-metal anode, LiFePO 4 and sulfur composite cathodes), but also afford good cycling performances for the Li|LiFePO 4 (>300 cycles at 1C) and Li-S cells (>500 cycles at 0.5C), in comparison with the conventional LiTFSI (Li[(CF 3 SO 2 ) 2 N])-based SPEs. The interfacial impedance and morphology of the cycled Li-metal electrodes are also comparatively analyzed by electrochemical impedance spectra and scanning electron microscopy, respectively. These indicate that the LiTNFSI-based SPEs would be potential alternatives for application in high-energy solid-state Li batteries.

  16. Electrode-Impregnable and Cross-Linkable Poly(ethylene oxide)-Poly(propylene oxide)-Poly(ethylene oxide) Triblock Polymer Electrolytes with High Ionic Conductivity and a Large Voltage Window for Flexible Solid-State Supercapacitors.

    PubMed

    Han, Jae Hee; Lee, Jang Yong; Suh, Dong Hack; Hong, Young Taik; Kim, Tae-Ho

    2017-10-04

    We present cross-linkable precursor-type gel polymer electrolytes (GPEs) that have large ionic liquid uptake capability, can easily penetrate electrodes, have high ion conductivity, and are mechanically strong as high-performance, flexible all-solid-state supercapacitors (SC). Our polymer precursors feature a hydrophilic-hydrophobic poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock main-chain structure and trifunctional silane end groups that can be multi-cross-linked with each other through a sol-gel process. The cross-linked solid-state electrolyte film with moderate IL content (200 wt %) shows a well-balanced combination of excellent ionic conductivity (5.0 × 10 -3 S cm -1 ) and good mechanical stability (maximum strain = 194%). Moreover, our polymer electrolytes have various advantages including high thermal stability (decomposition temperature > 330 °C) and the capability to impregnate electrodes to form an excellent electrode-electrolyte interface due to the very low viscosity of the precursors. By assembling our GPE-impregnated electrodes and solid-state GPE film, we demonstrate an all-solid-state SC that can operate at 3 V and provides an improved specific capacitance (112.3 F g -1 at 0.1 A g -1 ), better rate capability (64% capacity retention until 20 A g -1 ), and excellent cycle stability (95% capacitance decay over 10 000 charge/discharge cycles) compared with those of a reference SC using a conventional PEO electrolyte. Finally, flexible SCs with a high energy density (22.6 W h kg -1 at 1 A g -1 ) and an excellent flexibility (>93% capacitance retention after 5000 bending cycles) can successfully be obtained.

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Utilization of municipal solid and liquid wastes for bioenergy and bioproducts production.

    PubMed

    Chen, Paul; Xie, Qinglong; Addy, Min; Zhou, Wenguang; Liu, Yuhuan; Wang, Yunpu; Cheng, Yanling; Li, Kun; Ruan, Roger

    2016-09-01

    Municipal wastes, be it solid or liquid, are rising due to the global population growth and rapid urbanization and industrialization. Conventional management practice involving recycling, combustion, and treatment/disposal is deemed unsustainable. Solutions must be sought to not only increase the capacity but also improve the sustainability of waste management. Research has demonstrated that the non-recyclable waste materials and bio-solids can be converted into useable heat, electricity, or fuel and chemical through a variety of processes, including gasification, pyrolysis, anaerobic digestion, and landfill gas in addition to combustion, and wastewater streams have the potential to support algae growth and provide other energy recovery options. The present review is intended to assess and analyze the current state of knowledge in the municipal solid wastes and wastewater treatment and utilization technologies and recommend practical solution options and future research and development needs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Effect of Process Parameter on Barium Titanate Stannate (BTS) Materials Sintered at Low Sintering

    NASA Astrophysics Data System (ADS)

    Shukla, Alok; Bajpai, P. K.

    2011-11-01

    Ba(Ti1-xSnx)O3 solid solutions with (x = 0.15, 0.20, 0.30 and 0.40) are synthesized using conventional solid state reaction method. Formation of solid solutions in the range 0 ≤ x ≤0.40 is confirmed using X-ray diffraction technique. Single phase solid solutions with homogeneous grain distribution are observed at relatively low sintering by controlling process parameters viz. sintering time. Composition at optimized temperature (1150 °C) sintered by varying the sintering time, stabilize in cubic perovskite phase. The % experimental density increase with increasing the time of sintering instead of increasing sintering temperature. The lattice parameter increases by increasing the tin composition in the material. This demonstrates that process parameter optimization can lead to single phase at relatively lower sintering-a major advantage for the materials used as capacitor element in MLCC.

  20. Innovative processing of dense LSGM electrolytes for IT-SOFC's

    NASA Astrophysics Data System (ADS)

    Rambabu, B.; Ghosh, Samrat; Zhao, Weichang; Jena, Hrudananda

    This paper reports for the first time the attempted synthesis of SrO- and MgO-doped LaGaO 3 (La 1- xSr xGa 1- yMg yO 3-0.5(x+ y), LSGM) perovskite by an aqueous 'regenerative' solution route. This novel technique enabled recycling of the undesired product and subsequently yielded product with much better phase purity and density than that obtained from the solid-state route. La 0.8Sr 0.2Ga 0.85Mg 0.15O 2.825 (LSGM-2015) and LaGaO 3 were prepared using both the regenerative sol-gel (RSG) and conventional solid-state route at 1400 °C. Series of La 0.8Sr 0.2Ga 0.83Mg 0.17O 2.815 (LSGM-2017) pellets were also prepared by the RSG method at different sintering temperature (1200-1500 °C) and time. The effect of conventional and microwave sintering of samples obtained from both solid-state and regenerative route was also investigated. Microwave heating was carried out using SiC as a microwave susceptor. The LSGM pellets prepared by using different synthetic methods were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and pellet density was determined by pycnometry. The LSGM-2015 prepared by RSG route exhibited conductivity σ t = 0.066 and 0.029 S cm -1 at 800 and 700 °C, respectively, and activation energy of the bulk, grain-boundary, and total are E b = 0.97 eV, E gb = 1.03 eV and E t = 1.01 eV, respectively. The sintering temperature severely affected the grain size (<0.1-10 μm) and also the grain-boundary resistance (3-175 kΩ). The unique aspect of this RSG technique is that the final product can be recycled which makes the process cost effective and time saving compared to the solid-state ceramic technique and this technique would allow optimization of processing parameters in a cost effective and time saving manner for obtaining well sintered LSGM as an electrolyte for IT-SOFC's.

  1. Removal of Strontium from Drinking Water by Conventional ...

    EPA Pesticide Factsheets

    The United States Environmental Protection Agency Contaminant Candidate List 3 lists strontium as a contaminant for potential regulatory consideration in drinking water. There is very little data available on strontium removal from drinking water. As a result, there is an immediate need to perform treatment studies. The objective of this work is to evaluate the effectiveness of conventional and lime-soda ash softening treatments to remove strontium from surface and ground waters. Conventional drinking water treatment with aluminum and iron coagulants were able to achieve 12% and 5.9% strontium removal at best, while lime softening removed as much as 78% from natural strontium-containing ground water. Systematic fundamental experiments showed that strontium removal during the lime-soda ash softening was related to pH, calcium concentration and dissolved inorganic carbon concentration. Final strontium concentration was also directly associated with initial strontium concentration. Precipitated solids showed well-formed crystals or agglomerates of mixed solids, two polymorphs of calcium carbonate (vaterite and calcite), and strontianite, depending on initial water quality conditions. X-ray diffraction analysis suggested that strontium likely replaced calcium inside the crystal lattice and was likely mainly responsible for removal during lime softening. To inform the public.

  2. Designed Synthesis of Mesoporous Solid-Supported Lewis Acid-Base Pairs and Their CO2 Adsorption Behaviors.

    PubMed

    Zakharova, Maria V; Masoumifard, Nima; Hu, Yimu; Han, Jongho; Kleitz, Freddy; Fontaine, Frédéric-Georges

    2018-04-18

    Conventional amines and phosphines, such as diethylenetriamine, diphenylpropylphosphine, triethylamine, and tetramethylpiperidine, were grafted or impregnated on the surface of metalated SBA-15 materials, such as Ti-, Al-, and Zr-SBA-15, to generate air-stable solid-supported Lewis acid-base pairs. The Lewis acidity of the metalated materials before and after the introduction of Lewis bases was verified by means of pyridine adsorption-Fourier transform infrared spectroscopy. Detailed characterization of the materials was achieved by solid-state 13 C and 31 P MAS NMR spectroscopy, low-temperature N 2 physisorption, X-ray photoelectron spectroscopy, and energy-dispersive X-ray mapping analyses. Study of their potential interactions with CO 2 was performed using CO 2 adsorption isotherm experiments, which provided new insights into their applicability as solid CO 2 adsorbents. A correlation between solid-supported Lewis acid-base pair strength and the resulting affinity to CO 2 is discussed based on the calculation of isosteric enthalpy of adsorption.

  3. Low temperature magnetic properties of GdFeO3

    NASA Astrophysics Data System (ADS)

    Paul, Pralay; Prajapat, C. L.; Rajarajan, A. K.; Rao, T. V. Chandrasekhar

    2018-04-01

    Polycrystalline GdFeO3 was prepared using conventional solid state reaction method. Magnetization studies at low temperatures show antiferromagnetic ordering of Gd moments at ˜2.5K. Saturation in magnetization is noted at 2K under moderate magnetic fields, a result hitherto unreported. We conjecture that such a saturation is indicative of weakening of Dzyaloshinskii-Moriya interaction between Gd and Fe sublattices.

  4. Three-Dimensional Solid-State Lithium-Ion Batteries Fabricated by Conformal Vapor-Phase Chemistry.

    PubMed

    Pearse, Alexander; Schmitt, Thomas; Sahadeo, Emily; Stewart, David M; Kozen, Alexander; Gerasopoulos, Konstantinos; Talin, A Alec; Lee, Sang Bok; Rubloff, Gary W; Gregorczyk, Keith E

    2018-05-22

    Three-dimensional thin-film solid-state batteries (3D TSSB) were proposed by Long et al. in 2004 as a structure-based approach to simultaneously increase energy and power densities. Here, we report experimental realization of fully conformal 3D TSSBs, demonstrating the simultaneous power-and-energy benefits of 3D structuring. All active battery components-electrodes, solid electrolyte, and current collectors-were deposited by atomic layer deposition (ALD) onto standard CMOS processable silicon wafers microfabricated to form arrays of deep pores with aspect ratios up to approximately 10. The cells utilize an electrochemically prelithiated LiV 2 O 5 cathode, a very thin (40-100 nm) Li 2 PO 2 N solid electrolyte, and a SnN x anode. The fabrication process occurs entirely at or below 250 °C, promising compatibility with a variety of substrates as well as integrated circuits. The multilayer battery structure enabled all-ALD solid-state cells to deliver 37 μAh/cm 2 ·μm (normalized to cathode thickness) with only 0.02% per-cycle capacity loss. Conformal fabrication of full cells over 3D substrates increased the areal discharge capacity by an order of magnitude while simulteneously improving power performance, a trend consistent with a finite element model. This work shows that the exceptional conformality of ALD, combined with conventional semiconductor fabrication methods, provides an avenue for the successful realization of long-sought 3D TSSBs which provide power performance scaling in regimes inaccessible to planar form factor cells.

  5. Improved Dielectric Properties via Mechano-Chemical Activation in Ba0.80Pb0.20TiO3 Ceramics

    NASA Astrophysics Data System (ADS)

    Kumar, Parveen; Rani, Renu; Singh, Sangeeta; Juneja, J. K.; Prakash, Chandra; Raina, K. K.

    2011-12-01

    The present report is about the preparation and dielectric properties of commonly used Ba0.80Pb0.20TiO3 (BPT) ferroelectric ceramic via Mechano-Chemical Activation (MCA). Results were compared by the BPT sample prepared by conventional solid state method. The BPT sample prepared via MCA technique was found to have decreased tetragonality, dielectric constant value (ɛRT = 450 and ɛmax = 6170) approximately double the value for sample prepared by conventional method (ɛRT = 260 and ɛmax = 3275). Also, the sample prepared by MCA was found to be less frequency dependent. Thus, the BPT sample prepared via MCA is more suitable for capacitor applications requiring lesser frequency dependency than the conventionally prepared BPT sample.

  6. Spin-echo based diagonal peak suppression in solid-state MAS NMR homonuclear chemical shift correlation spectra

    NASA Astrophysics Data System (ADS)

    Wang, Kaiyu; Zhang, Zhiyong; Ding, Xiaoyan; Tian, Fang; Huang, Yuqing; Chen, Zhong; Fu, Riqiang

    2018-02-01

    The feasibility of using the spin-echo based diagonal peak suppression method in solid-state MAS NMR homonuclear chemical shift correlation experiments is demonstrated. A complete phase cycling is designed in such a way that in the indirect dimension only the spin diffused signals are evolved, while all signals not involved in polarization transfer are refocused for cancellation. A data processing procedure is further introduced to reconstruct this acquired spectrum into a conventional two-dimensional homonuclear chemical shift correlation spectrum. A uniformly 13C, 15N labeled Fmoc-valine sample and the transmembrane domain of a human protein, LR11 (sorLA), in native Escherichia coli membranes have been used to illustrate the capability of the proposed method in comparison with standard 13C-13C chemical shift correlation experiments.

  7. Aircraft Photovoltaic Power-Generating System.

    NASA Astrophysics Data System (ADS)

    Doellner, Oscar Leonard

    Photovoltaic cells, appropriately cooled and operating in the combustion-created high radiant-intensity environment of gas-turbine and jet engines, may replace the conventional (gearbox-driven) electrical power generators aboard jet aircraft. This study projects significant improvements not only in aircraft electrical power-generating-system performance, but also in overall aircraft performance. Jet -engine design modifications incorporating this concept not only save weight (and thus fuel), but are--in themselves --favorable to jet-engine performance. The dissertation concentrates on operational, constructional, structural, thermal, optical, radiometrical, thin-film, and solid-state theoretical aspects of the overall project. This new electrical power-generating system offers solid-state reliability with electrical power-output capability comparable to that of existing aircraft electromechanical power-generating systems (alternators and generators). In addition to improvements in aircraft performance, significant aircraft fuel- and weight-saving advantages are projected.

  8. High piezoelectric performance of poly(lactic acid) film manufactured by solid-state extrusion

    NASA Astrophysics Data System (ADS)

    Yoshida, Mitsunobu; Onogi, Takayuki; Onishi, Katsuki; Inagaki, Takuma; Tajitsu, Yoshiro

    2014-09-01

    Recently, the application of uniaxially stretched poly(l-lactic acid) (PLLA) films to speakers, actuators, and pressure sensors has been attempted, taking advantage of their piezoelectric performance. However, the shear piezoelectric constant d14 of uniaxially stretched PLLA film is conventionally 6-10 pC N-1. To realize a high sensitivity of pressure sensors, compact speakers, and actuators, and a low driving voltage, further improvement of the piezoelectric performance is desired. In this study, we carried out solid-state extrusion (SSE) to stretch and orient poly(d-lactic acid) (PDLA) and verified its effects on piezoelectric performance. By SSE, we were able to improve the mechanical strength and elastic modulus of PDLA samples. Furthermore, the d14 of the samples was significantly increased to approximately 20 pC N-1.

  9. Adapting radio technology to LED feedback systems

    NASA Astrophysics Data System (ADS)

    Salsbury, Marc; Ashdown, Ian

    2007-09-01

    Superheterodyne techniques were originally developed for radio transmission and reception nearly a century ago. In this paper we explore the adaptation of this technology to the problem of simultaneously monitoring the intensities of multiple LED channels with a single photosensor. The use of superheterodyne techniques obviates the need for multiple photosensors filters and tristimulus color filters to monitor the relative intensities of red, green, and blue LEDs. In addition, they alleviate the problems of electrical and optical noise, as well as the influence of ambient illumination on the photosensors. They can also be used to advantage with phosphor-coated white light LEDs in solid state lighting systems. Taking a broader view, the use of such techniques demonstrates the value of looking outside the realm of conventional LED power and control technologies when designing solid state lighting systems.

  10. Flexible Asymmetrical Solid-State Supercapacitors Based on Laboratory Filter Paper.

    PubMed

    Zhang, Leicong; Zhu, Pengli; Zhou, Fengrui; Zeng, Wenjin; Su, Haibo; Li, Gang; Gao, Jihua; Sun, Rong; Wong, Ching-Ping

    2016-01-26

    In this study, a flexible asymmetrical all-solid-state supercapacitor with high electrochemical performance was fabricated with Ni/MnO2-filter paper (FP) as the positive electrode and Ni/active carbon (AC)-filter paper as negative electrode, separated with poly(vinyl alcohol) (PVA)-Na2SO4 electrolyte. A simple procedure, such as electroless plating, was introduced to prepare the Ni/MnO2-FP electrode on the conventional laboratory FP, combined with the subsequent step of electrodeposition. Electrochemical results show that the as-prepared electrodes display outstanding areal specific capacitance (1900 mF/cm(2) at 5 mV/s) and excellent cycling performance (85.1% retention after 1000 cycles at 20 mA/cm(2)). Such a flexible supercapacitor assembled asymmetrically in the solid state exhibits a large volume energy density (0.78 mWh/cm(3)) and superior flexibility under different bending conditions. It has been demonstrated that the supercapacitors could be used as a power source to drive a 3 V light-emitting diode indicator. This study may provide an available method for designing and fabricating flexible supercapacitors with high performance in the application of wearable and portable electronics based on easily available materials.

  11. Preparation of Mo-Re-C samples containing Mo7Re13C with the β-Mn-type structure by solid state reaction of planetary-ball-milled powder mixtures of Mo, Re and C, and their crystal structures and superconductivity

    NASA Astrophysics Data System (ADS)

    Oh-ishi, Katsuyoshi; Nagumo, Kenta; Tateishi, Kazuya; Takafumi, Ohnishi; Yoshikane, Kenta; Sugiyama, Machiko; Oka, Kengo; Kobayashi, Ryota

    2017-01-01

    Mo-Re-C compounds containing Mo7Re13C with the β-Mn structure were synthesized with high-melting-temperature metals Mo, Re, and C powders using a conventional solid state method with a planetary ball milling machine instead of the arc melting method. Use of the ball milling machine was necessary to obtain Mo7Re13C with the β-Mn structure using the solid state method. Almost single-phase Mo7Re13C with a trace of impurity were obtained using the synthesis method. By XRF and lattice parameter measurements on the samples, Fe element existed in the compound synthesized using the planetary ball milling machine with a pot and balls made of steel, though Fe element was not detected in the compound synthesized using a pot and balls made of tungsten carbide. The former compound containg the Fe atom did not show superconductivity but the latter compound without the Fe atom showed superconductivity at 6.1 K.

  12. A facile method to prepare "green" nano-phosphors with a large Stokes-shift and solid-state enhanced photophysical properties based on surface-modified gold nanoclusters.

    PubMed

    Cheng, C H; Huang, H Y; Talite, M J; Chou, W C; Yeh, J M; Yuan, C T

    2017-12-15

    Colloidal nano-materials, such as quantum dots (QDs) have been applied to light-conversion nano-phosphors due to their unique tunable emission. However, most of the QDs involve toxic elements and are synthesized in a hazardous solvent. In addition, conventional QD nano-phosphors with a small Stokes shift suffered from reabsorption losses and aggregation-induced quenching in the solid state. Here, we demonstrate a facile, matrix-free method to prepare eco-friendly nano-phosphors with a large Stokes shift based on aqueous thiolate-stabilized gold nanoclusters (GSH-AuNCs) with simple surface modifications. Our method is just to drop GSH-AuNCs solution on the aluminum foil and then surface-modified AuNCs (Al-GSH-AuNCs) can be spontaneously precipitated out of the aqueous solution. Compared with pristine GSH-AuNCs in solution, the Al-GSH-AuNCs exhibit enhanced solid-state PL quantum yields, lengthened PL lifetime, and spectral blue shift, which can be attributed to the aggregation-induced emission enhancement facilitated by surface modifications. Such surface-treatment induced aggregation of AuNCs can restrict the surface-ligand motion, leading to the enhancement of PL properties in the solid state. In addition, the Al-GSH-AuNCs nano-phosphors with a large Stokes shift can mitigate the aggregation-induced PL quenching and reabsorption losses, which would be potential candidates for "green" nano-phosphors. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Comparison of conventional and automated breast volume ultrasound in the description and characterization of solid breast masses based on BI-RADS features.

    PubMed

    Kim, Hyunji; Cha, Joo Hee; Oh, Ha-Yeun; Kim, Hak Hee; Shin, Hee Jung; Chae, Eun Young

    2014-07-01

    To compare the performance of radiologists in the use of conventional ultrasound (US) and automated breast volume ultrasound (ABVU) for the characterization of benign and malignant solid breast masses based on breast imaging and reporting data system (BI-RADS) criteria. Conventional US and ABVU images were obtained in 87 patients with 106 solid breast masses (52 cancers, 54 benign lesions). Three experienced radiologists who were blinded to all examination results independently characterized the lesions and reported a BI-RADS assessment category and a level of suspicion of malignancy. The results were analyzed by calculation of Cohen's κ coefficient and by receiver operating characteristic (ROC) analysis. Assessment of the agreement of conventional US and ABVU indicated that the posterior echo feature was the most discordant feature of seven features (κ = 0.371 ± 0.225) and that orientation had the greatest agreement (κ = 0.608 ± 0.210). The final assessment showed substantial agreement (κ = 0.773 ± 0.104). The areas under the ROC curves (Az) for conventional US and ABVU were not statistically significant for each reader, but the mean Az values of conventional US and ABVU by multi-reader multi-case analysis were significantly different (conventional US 0.991, ABVU 0.963; 95 % CI -0.0471 to -0.0097). The means for sensitivity, specificity, positive predictive value, and negative predictive value of conventional US and ABVU did not differ significantly. There was substantial inter-observer agreement in the final assessment of solid breast masses by conventional US and ABVU. ROC analysis comparing the performance of conventional US and ABVU indicated a marginally significant difference in mean Az, but not in mean sensitivity, specificity, positive predictive value, or negative predictive value.

  14. Uses of continuum radiation in the AXAF calibration

    NASA Technical Reports Server (NTRS)

    Kolodziejczak, J. J.; Austin, R. A.; Elsner, R. F.; O'Dell, S. L.; Sulkanen, M. E.; Swartz, D. A.; Tennant, A. F.; Weisskopf, M. C.; Zirnstein, G.; McDermott, W. C.

    1997-01-01

    X-ray calibration of the Advanced X-ray Astrophysics Facility (AXAF) observatory at the MSFC X-Ray Calibration Facility (XRCF) made novel use of the x-ray continuum from a conventional electron-impact source. Taking advantage of the good spectral resolution of solid-state detectors, continuum measurements proved advantageous in calibrating the effective area of AXAF's High-Resolution Mirror Assembly (HRMA) and in verifying its alignment to the XRCF's optical axis.

  15. Transforming from planar to three-dimensional lithium with flowable interphase for solid lithium metal batteries

    PubMed Central

    Liu, Yayuan; Lin, Dingchang; Jin, Yang; Liu, Kai; Tao, Xinyong; Zhang, Qiuhong; Zhang, Xiaokun; Cui, Yi

    2017-01-01

    Solid-state lithium (Li) metal batteries are prominent among next-generation energy storage technologies due to their significantly high energy density and reduced safety risks. Previously, solid electrolytes have been intensively studied and several materials with high ionic conductivity have been identified. However, there are still at least three obstacles before making the Li metal foil-based solid-state systems viable, namely, high interfacial resistance at the Li/electrolyte interface, low areal capacity, and poor power output. The problems are addressed by incorporating a flowable interfacial layer and three-dimensional Li into the system. The flowable interfacial layer can accommodate the interfacial fluctuation and guarantee excellent adhesion at all time, whereas the three-dimensional Li significantly reduces the interfacial fluctuation from the whole electrode level (tens of micrometers) to local scale (submicrometer) and also decreases the effective current density for high-capacity and high-power operations. As a consequence, both symmetric and full-cell configurations can achieve greatly improved electrochemical performances in comparison to the conventional Li foil, which are among the best reported values in the literature. Noticeably, solid-state full cells paired with high–mass loading LiFePO4 exhibited, at 80°C, a satisfactory specific capacity even at a rate of 5 C (110 mA·hour g−1) and a capacity retention of 93.6% after 300 cycles at a current density of 3 mA cm−2 using a composite solid electrolyte middle layer. In addition, when a ceramic electrolyte middle layer was adopted, stable cycling with greatly improved capacity could even be realized at room temperature. PMID:29062894

  16. Transforming from planar to three-dimensional lithium with flowable interphase for solid lithium metal batteries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Yayuan; Lin, Dingchang; Jin, Yang

    Solid-state lithium (Li) metal batteries are prominent among next-generation energy storage technologies due to their significantly high energy density and reduced safety risks. Previously, solid electrolytes have been intensively studied and several materials with high ionic conductivity have been identified. However, there are still at least three obstacles before making the Li metal foil-based solid-state systems viable, namely, high interfacial resistance at the Li/electrolyte interface, low areal capacity, and poor power output. The problems are addressed by incorporating a flowable interfacial layer and three-dimensional Li into the system. The flowable interfacial layer can accommodate the interfacial fluctuation and guarantee excellentmore » adhesion at all time, whereas the three-dimensional Li significantly reduces the interfacial fluctuation from the whole electrode level (tens of micrometers) to local scale (submicrometer) and also decreases the effective current density for high-capacity and high-power operations. As a consequence, both symmetric and full-cell configurations can achieve greatly improved electrochemical performances in comparison to the conventional Li foil, which are among the best reported values in the literature. Noticeably, solid-state full cells paired with high–mass loading LiFePO4 exhibited, at 80°C, a satisfactory specific capacity even at a rate of 5 C (110 mA·hour g -1) and a capacity retention of 93.6% after 300 cycles at a current density of 3 mA cm -2 using a composite solid electrolyte middle layer. In addition, when a ceramic electrolyte middle layer was adopted, stable cycling with greatly improved capacity could even be realized at room temperature.« less

  17. Transforming from planar to three-dimensional lithium with flowable interphase for solid lithium metal batteries

    DOE PAGES

    Liu, Yayuan; Lin, Dingchang; Jin, Yang; ...

    2017-10-01

    Solid-state lithium (Li) metal batteries are prominent among next-generation energy storage technologies due to their significantly high energy density and reduced safety risks. Previously, solid electrolytes have been intensively studied and several materials with high ionic conductivity have been identified. However, there are still at least three obstacles before making the Li metal foil-based solid-state systems viable, namely, high interfacial resistance at the Li/electrolyte interface, low areal capacity, and poor power output. The problems are addressed by incorporating a flowable interfacial layer and three-dimensional Li into the system. The flowable interfacial layer can accommodate the interfacial fluctuation and guarantee excellentmore » adhesion at all time, whereas the three-dimensional Li significantly reduces the interfacial fluctuation from the whole electrode level (tens of micrometers) to local scale (submicrometer) and also decreases the effective current density for high-capacity and high-power operations. As a consequence, both symmetric and full-cell configurations can achieve greatly improved electrochemical performances in comparison to the conventional Li foil, which are among the best reported values in the literature. Noticeably, solid-state full cells paired with high–mass loading LiFePO4 exhibited, at 80°C, a satisfactory specific capacity even at a rate of 5 C (110 mA·hour g -1) and a capacity retention of 93.6% after 300 cycles at a current density of 3 mA cm -2 using a composite solid electrolyte middle layer. In addition, when a ceramic electrolyte middle layer was adopted, stable cycling with greatly improved capacity could even be realized at room temperature.« less

  18. Enhanced Multiferroic Properties of YMnO3 Ceramics Fabricated by Spark Plasma Sintering Along with Low-Temperature Solid-State Reaction

    PubMed Central

    Wang, Meng; Wang, Ting; Song, Shenhua; Ravi, Muchakayala; Liu, Renchen; Ji, Shishan

    2017-01-01

    Based on precursor powders with a size of 200–300 nm prepared by the low-temperature solid-state reaction method, phase-pure YMnO3 ceramics are fabricated using spark plasma sintering (SPS). X-ray diffraction (XRD) and scanning electron microscopy (SEM) reveal that the high-purity YMnO3 ceramics can be prepared by SPS at 1000 °C for 5 minutes with annealing at 800 °C for 2 h. The relative density of the sample is as high as 97%, which is much higher than those of the samples sintered by other methods. The present dielectric and magnetic properties are much better than those of the samples fabricated by conventional methods and SPS with ball-milling precursors, and the ferroelectric loops at room temperature can be detected. These findings indicate that the YMnO3 ceramics prepared by the low temperature solid reaction method and SPS possess excellent dielectric lossy ferroelectric properties at room temperature, and magnetic properties at low temperature (10 K), making them suitable for potential multiferroic applications. PMID:28772832

  19. Modeling combined heat transfer in an all solid state optical cryocooler

    NASA Astrophysics Data System (ADS)

    Kuzhiveli, Biju T.

    2017-12-01

    Attaining cooling effect by using laser induced anti-Stokes fluorescence in solids appears to have several advantages over conventional mechanical systems and has been the topic of recent analysis and experimental work. Using anti-Stokes fluorescence phenomenon to remove heat from a glass by pumping it with laser light, stands as a pronouncing physical basis for solid state cooling. Cryocooling by fluorescence is a feasible solution for obtaining compactness and reliability. It has a distinct niche in the family of small capacity cryocoolers and is undergoing a revolutionary advance. In pursuit of developing laser induced anti-Stokes fluorescent cryocooler, it is required to develop numerical tools that support the thermal design which could provide a thorough analysis of combined heat transfer mechanism within the cryocooler. The paper presents the details of numerical model developed for the cryocooler and the subsequent development of a computer program. The program has been used for the understanding of various heat transfer mechanisms and is being used for thermal design of components of an anti-Stokes fluorescent cryocooler.

  20. Bose-Einstein Condensates in 1D Optical Lattices: Nonlinearity and Wannier-Stark Spectra

    NASA Astrophysics Data System (ADS)

    Arimondo, Ennio; Ciampini, Donatella; Morsch, Oliver

    The development of powerful laser cooling and trapping techniques has made possible the controlled realization of dense and cold gaseous samples, thus opening the way for investigations in the ultracold temperature regimes not accessible with conventional techniques. A Bose-Einstein condensate (BEC) represents a peculiar gaseous state where all the particles reside in the same quantum mechanical state. Therefore BECs exhibit quantum mechanical phe-nomena on a macroscopic scale with a single quantum mechanical wavefunction describing the external degrees of freedom. That control of the external degrees of freedom is combined with a precise control of the internal degrees. The BEC investigation has become a very active area of research in contem-porary physics. The BEC study encompasses different subfields of physics, i.e., atomic and molecular physics, quantum optics, laser spectroscopy, solid state physics. Atomic physics and laser spectroscopy provide the methods for creating and manipulating the atomic and molecular BECs. However owing to the interactions between the particles composing the condensate and to the configuration of the external potential, concepts and methods from solid state physics are extensively used for BEC description.

  1. Solid state power controllers

    NASA Technical Reports Server (NTRS)

    Gibbs, R. S.

    1973-01-01

    The rationale, analysis, design, breadboarding and testing of the incremental functional requirements are reported that led to the development of prototype 1 and 5 Amp dc and 1 Amp ac solid state power controllers (SSPC's). The SSPC's are to be considered for use as a replacement of electro-mechanical relays and circuit breakers in future spacecraft and aircraft. They satisfy the combined function of both the relay and circuit breaker and can be remotely controlled by small signals, typically 10 mA, 5 to 28 Vdc. They have the advantage over conventional relay/circuit breaker systems in that they can be located near utilization equipment and the primary ac or dc bus. The low level control, trip indication and status signals can be circuited by small guage wire for control, computer interface, logic, electrical multiplexing, unboard testing, and power management and distribution purposes. This results in increased system versatility at appreciable weight saving and increased reliability.

  2. Using Solid State Disk Array as a Cache for LHC ATLAS Data Analysis

    NASA Astrophysics Data System (ADS)

    Yang, W.; Hanushevsky, A. B.; Mount, R. P.; Atlas Collaboration

    2014-06-01

    User data analysis in high energy physics presents a challenge to spinning-disk based storage systems. The analysis is data intense, yet reads are small, sparse and cover a large volume of data files. It is also unpredictable due to users' response to storage performance. We describe here a system with an array of Solid State Disk as a non-conventional, standalone file level cache in front of the spinning disk storage to help improve the performance of LHC ATLAS user analysis at SLAC. The system uses several days of data access records to make caching decisions. It can also use information from other sources such as a work-flow management system. We evaluate the performance of the system both in terms of caching and its impact on user analysis jobs. The system currently uses Xrootd technology, but the technique can be applied to any storage system.

  3. Holistic Assessment and Ethical Disputation on a New Trend in Solid Biofuels.

    PubMed

    Hašková, Simona

    2017-04-01

    A new trend in the production technology of solid biof uels has appeared. There is a wide consensus that most solid biofuels will be produced according to the new production methods within a few years. Numerous samples were manufactured from agro-residues according to conventional methods as well as new methods. Robust analyses that reviewed the hygienic, environmental, financial and ethical aspects were performed. The hygienic and environmental aspect was assessed by robust chemical and technical analyses. The financial aspect was assessed by energy cost breakdown. The ethical point of view was built on the above stated findings, the survey questionnaire and critical discussion with the literature. It is concluded that the new production methods are significantly favourable from both the hygienic and environmental points of view. Financial indicators do not allow the expressing of any preference. Regarding the ethical aspect, it is concluded that the new methods are beneficial in terms of environmental responsibility. However, it showed that most of the customers that took part in the survey are price oriented and therefore they tend to prefer the cheaper-conventional alternative. In the long term it can be assumed that expansion of the new technology and competition among manufacturers will reduce the costs.

  4. Field-Controlled Electrical Switch with Liquid Metal.

    PubMed

    Wissman, James; Dickey, Michael D; Majidi, Carmel

    2017-12-01

    When immersed in an electrolyte, droplets of Ga-based liquid metal (LM) alloy can be manipulated in ways not possible with conventional electrocapillarity or electrowetting. This study demonstrates how LM electrochemistry can be exploited to coalesce and separate droplets under moderate voltages of ~1-10 V. This novel approach to droplet interaction can be explained with a theory that accounts for oxidation and reduction as well as fluidic instabilities. Based on simulations and experimental analysis, this study finds that droplet separation is governed by a unique limit-point instability that arises from gradients in bipolar electrochemical reactions that lead to gradients in interfacial tension. The LM coalescence and separation are used to create a field-programmable electrical switch. As with conventional relays or flip-flop latch circuits, the system can transition between bistable (separated or coalesced) states, making it useful for memory storage, logic, and shape-programmable circuitry using entirely liquids instead of solid-state materials.

  5. Garnet-type solid-state fast Li ion conductors for Li batteries: critical review.

    PubMed

    Thangadurai, Venkataraman; Narayanan, Sumaletha; Pinzaru, Dana

    2014-07-07

    Batteries are electrochemical devices that store electrical energy in the form of chemical energy. Among known batteries, Li ion batteries (LiBs) provide the highest gravimetric and volumetric energy densities, making them ideal candidates for use in portable electronics and plug-in hybrid and electric vehicles. Conventional LiBs use an organic polymer electrolyte, which exhibits several safety issues including leakage, poor chemical stability and flammability. The use of a solid-state (ceramic) electrolyte to produce all-solid-state LiBs can overcome all of the above issues. Also, solid-state Li batteries can operate at high voltage, thus, producing high power density. Various types of solid Li-ion electrolytes have been reported; this review is focused on the most promising solid Li-ion electrolytes based on garnet-type metal oxides. The first studied Li-stuffed garnet-type compounds are Li5La3M2O12 (M = Nb, Ta), which show a Li-ion conductivity of ∼10(-6) at 25 °C. La and M sites can be substituted by various metal ions leading to Li-rich garnet-type electrolytes, such as Li6ALa2M2O12, (A = Mg, Ca, Sr, Ba, Sr0.5Ba0.5) and Li7La3C2O12 (C = Zr, Sn). Among the known Li-stuffed garnets, Li6.4La3Zr1.4Ta0.6O12 exhibits the highest bulk Li-ion conductivity of 10(-3) S cm(-1) at 25 °C with an activation energy of 0.35 eV, which is an order of magnitude lower than that of the currently used polymer, but is chemically stable at higher temperatures and voltages compared to polymer electrolytes. Here, we discuss the chemical composition-structure-ionic conductivity relationship of the Li-stuffed garnet-type oxides, as well as the Li ion conduction mechanism.

  6. NQR: From imaging to explosives and drugs detection

    NASA Astrophysics Data System (ADS)

    Osán, Tristán M.; Cerioni, Lucas M. C.; Forguez, José; Ollé, Juan M.; Pusiol, Daniel J.

    2007-02-01

    The main aim of this work is to present an overview of the nuclear quadrupole resonance (NQR) spectroscopy capabilities for solid state imaging and detection of illegal substances, such as explosives and drugs. We briefly discuss the evolution of different NQR imaging techniques, in particular those involving spatial encoding which permit conservation of spectroscopic information. It has been shown that plastic explosives and other forbidden substances cannot be easily detected by means of conventional inspection techniques, such as those based on conventional X-ray technology. For this kind of applications, the experimental results show that the information inferred from NQR spectroscopy provides excellent means to perform volumetric and surface detection of dangerous explosive and drug compounds.

  7. Linking high harmonics from gases and solids.

    PubMed

    Vampa, G; Hammond, T J; Thiré, N; Schmidt, B E; Légaré, F; McDonald, C R; Brabec, T; Corkum, P B

    2015-06-25

    When intense light interacts with an atomic gas, recollision between an ionizing electron and its parent ion creates high-order harmonics of the fundamental laser frequency. This sub-cycle effect generates coherent soft X-rays and attosecond pulses, and provides a means to image molecular orbitals. Recently, high harmonics have been generated from bulk crystals, but what mechanism dominates the emission remains uncertain. To resolve this issue, we adapt measurement methods from gas-phase research to solid zinc oxide driven by mid-infrared laser fields of 0.25 volts per ångström. We find that when we alter the generation process with a second-harmonic beam, the modified harmonic spectrum bears the signature of a generalized recollision between an electron and its associated hole. In addition, we find that solid-state high harmonics are perturbed by fields so weak that they are present in conventional electronic circuits, thus opening a route to integrate electronics with attosecond and high-harmonic technology. Future experiments will permit the band structure of a solid to be tomographically reconstructed.

  8. Proton conducting ceramics in membrane separations

    DOEpatents

    Brinkman, Kyle S; Korinko, Paul S; Fox, Elise B; Chen, Frank

    2015-04-14

    Perovskite materials of the general formula SrCeO.sub.3 and BaCeO.sub.3 are provided having improved conductivity while maintaining an original ratio of chemical constituents, by altering the microstructure of the material. A process of making Pervoskite materials is also provided in which wet chemical techniques are used to fabricate nanocrystalline ceramic materials which have improved grain size and allow lower temperature densification than is obtainable with conventional solid-state reaction processing.

  9. Optical devices featuring nonpolar textured semiconductor layers

    DOEpatents

    Moustakas, Theodore D; Moldawer, Adam; Bhattacharyya, Anirban; Abell, Joshua

    2013-11-26

    A semiconductor emitter, or precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate in a nonpolar orientation. The textured layers enhance light extraction, and the use of nonpolar orientation greatly enhances internal quantum efficiency compared to conventional devices. Both the internal and external quantum efficiencies of emitters of the invention can be 70-80% or higher. The invention provides highly efficient light emitting diodes suitable for solid state lighting.

  10. Rotational fluxons of Bose-Einstein condensates in coplanar double-ring traps

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brand, J.; Institute of Natural Sciences, Massey University; Haigh, T. J.

    Rotational analogs to magnetic fluxons in conventional Josephson junctions are predicted to emerge in the ground state of rotating tunnel-coupled annular Bose-Einstein condensates (BECs). Such topological condensate-phase structures can be manipulated by external potentials. We determine conditions for observing macroscopic quantum tunneling of a fluxon. Rotational fluxons in double-ring BECs can be created, manipulated, and controlled by external potentials in different ways than is possible in the solid-state system, thus rendering them a promising candidate system for studying and utilizing quantum properties of collective many-particle degrees of freedom.

  11. Enhanced photoluminescence of SrWO{sub 4}:Eu{sup 3+} red phosphor synthesized by mechanochemically assisted solid state metathesis reaction method at room temperature

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peter, Anthuvan John, E-mail: quantajohn@gmail.com; Banu, I. B. Shameem

    2015-06-24

    Optically efficient europium activated alkaline earth metal tungstate nano phosphor (SrWO{sub 4}) with different doping concentrations have been synthesized by mechanochemically assisted solid state metathesis reaction at room temperature for the first time. The XRD and Raman spectra results indicated that the prepared powders exhibit a scheelite-type tetragonal structure. FTIR spectra exhibited a high absorption band situated at around 854 cm{sup −1}, which was ascribed to the W–O antisymmetric stretching vibrations into the [WO{sub 4}]{sup 2−} tetrahedron groups. Analysis of the emission spectra with different Eu{sup 3+} concentrations revealed that the optimum dopant concentration for SrWO{sub 4}: x Eu{sup 3+} phosphormore » is about 8 mol% of Eu{sup 3+}.The red emission intensity of the SSM prepared SrWO{sub 4}: 0.08Eu{sup 3+} phosphors are 2 times greater than that of the commercial Y{sub 2}O{sub 2}S: Eu{sup 3+} red phosphor prepared by the conventional solid state reaction method. All the results indicate that the phosphor is a promising red phosphor pumped by NUV InGaN chip for fabricating WLED.« less

  12. Present status of solid state photoelectrochemical solar cells and dye sensitized solar cells using PEO-based polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Singh, Pramod Kumar; Nagarale, R. K.; Pandey, S. P.; Rhee, H. W.; Bhattacharya, Bhaskar

    2011-06-01

    Due to energy crises in the future, much effort is being directed towards alternate sources. Solar energy is accepted as a novel substitute for conventional sources of energy. Out of the long list of various types of solar cells available on the market, solid state photoelectrochemical solar cells (SSPECs) and dye sensitized solar cells (DSSCs) are proposed as an alternative to costly crystalline solar cell. This review provides a common platform for SSPECs and DSSCs using polymer electrolyte, particularly on polyethylene oxide (PEO)-based polymer electrolytes. Due to numerous advantageous properties of PEO, it is frequently used as an electrolyte in both SSPECs as well as DSSCs. In DSSCs, so far high efficiency (more than 11%) has been obtained only by using volatile liquid electrolyte, which suffers many disadvantages, such as corrosion, leakage and evaporation. The PEO-based solid polymer proves its importance and could be used to solve the problems stated above. The recent developments in SSPECs and DSSCs using modified PEO electrolytes by adding nano size inorganic fillers, blending with low molecular weight polymers and ionic liquid (IL) are discussed in detail. The role of ionic liquid in modifying the electrical, structural and photoelectrochemical properties of PEO polymer electrolytes is also described.

  13. A LOW-E MAGIC ANGLE SPINNING PROBE FOR BIOLOGICAL SOLID STATE NMR AT 750 MHz

    PubMed Central

    McNeill, Seth A.; Gor’kov, Peter L.; Shetty, Kiran; Brey, William W.; Long, Joanna R.

    2009-01-01

    Crossed-coil NMR probes are a useful tool for reducing sample heating for biological solid state NMR. In a crossed-coil probe, the higher frequency 1H field, which is the primary source of sample heating in conventional probes, is produced by a separate low-inductance resonator. Because a smaller driving voltage is required, the electric field across the sample and the resultant heating is reduced. In this work we describe the development of a magic angle spinning (MAS) solid state NMR probe utilizing a dual resonator. This dual resonator approach, referred to as “Low-E,” was originally developed to reduce heating in samples of mechanically aligned membranes. The study of inherently dilute systems, such as proteins in lipid bilayers, via MAS techniques requires large sample volumes at high field to obtain spectra with adequate signal-to-noise ratio under physiologically relevant conditions. With the Low-E approach, we are able to obtain homogeneous and sufficiently strong radiofrequency fields for both 1H and 13C frequencies in a 4 mm probe with a 1H frequency of 750 MHz. The performance of the probe using windowless dipolar recoupling sequences is demonstrated on model compounds as well as membrane embedded peptides. PMID:19138870

  14. Raman spectroscopy, "big data", and local heterogeneity of solid state synthesized lithium titanate

    NASA Astrophysics Data System (ADS)

    Pelegov, Dmitry V.; Slautin, Boris N.; Gorshkov, Vadim S.; Zelenovskiy, Pavel S.; Kiselev, Evgeny A.; Kholkin, Andrei L.; Shur, Vladimir Ya.

    2017-04-01

    Existence of defects is an inherent property of real materials. Due to an explicit correlation between defects concentration and conductivity, it is important to understand the level and origins of the structural heterogeneity for any particulate electrode material. Poor conductive lithium titanate Li4Ti5O12 (LTO), widely used in batteries for grids and electric buses, needs it like no one else. In this work, structural heterogeneity of compacted lithium titanate is measured locally in 100 different points by conventional micro-Raman technique, characterized in terms of variation of Raman spectra parameters and interpreted using our version of "big data" analysis. This very simple approach with automated measurement and treatment has allowed us to demonstrate inherent heterogeneity of solid-state synthesized LTO and attribute it to the existence of lithium and oxygen vacancies. The proposed approach can be used as a fast, convenient, and cost-effective defects-probing tool for a wide range of materials with defects-sensitive properties. In case of LTO, such an approach can be used to increase its charge/discharge rates by synthesis of materials with controlled nonstoichiometry. New approaches to solid state synthesis of LTO, suitable for high-power applications, will help to significantly reduce the costs of batteries for heavy-duty electric vehicles and smart-grids.

  15. Large angle solid state position sensitive x-ray detector system

    DOEpatents

    Kurtz, David S.; Ruud, Clay O.

    1998-01-01

    A method and apparatus for x-ray measurement of certain properties of a solid material. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided.

  16. Evaluation of the operating performance of conventional versus flocculator secondary clarifiers at the Kuwahee Wastewater Treatment Plant, Knoxville, Tennessee.

    PubMed

    Moreno, Patricio A; Reed, Gregory D

    2007-05-01

    The difference in performance of three differently designed circular secondary clarifiers in the same wastewater treatment plant was analyzed in this paper. Data obtained using flocculated suspended solids and disperse suspended solids tests were analyzed using statistical tools. The conventional clarifier showed more variability in the average effluent suspended solids concentration when compared with the flocculator-clarifiers. Furthermore, a difference in performance among the two different flocculator-clarifiers was found.

  17. Novel electrosprayed nanospherules for enhanced aqueous solubility and oral bioavailability of poorly water-soluble fenofibrate

    PubMed Central

    Yousaf, Abid Mehmood; Mustapha, Omer; Kim, Dong Wuk; Kim, Dong Shik; Kim, Kyeong Soo; Jin, Sung Giu; Yong, Chul Soon; Youn, Yu Seok; Oh, Yu-Kyoung; Kim, Jong Oh; Choi, Han-Gon

    2016-01-01

    Purpose The purpose of the present research was to develop a novel electrosprayed nanospherule providing the most optimized aqueous solubility and oral bioavailability for poorly water-soluble fenofibrate. Methods Numerous fenofibrate-loaded electrosprayed nanospherules were prepared with polyvinylpyrrolidone (PVP) and Labrafil® M 2125 as carriers using the electrospray technique, and the effect of the carriers on drug solubility and solvation was assessed. The solid state characterization of an optimized formulation was conducted by scanning electron microscopy, powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopic analyses. Oral bioavailability in rats was also evaluated for the formulation of an optimized nanospherule in comparison with free drug and a conventional fenofibrate-loaded solid dispersion. Results All of the electrosprayed nanospherule formulations had remarkably enhanced aqueous solubility and dissolution compared with free drug. Moreover, Labrafil M 2125, a surfactant, had a positive influence on the solubility and dissolution of the drug in the electrosprayed nanospherule. Increases were observed as the PVP/drug ratio increased to 4:1, but higher ratios gave no significant increases. In particular, an electrosprayed nanospherule composed of fenofibrate, PVP, and Labrafil M 2125 at the weight ratio of 1:4:0.5 resulted in a particle size of <200 nm with the drug present in the amorphous state. It demonstrated the highest solubility (32.51±2.41 μg/mL), an excellent dissolution (~85% in 10 minutes), and an oral bioavailability ~2.5-fold better than that of the free drug. It showed similar oral bioavailability compared to the conventional solid dispersion. Conclusion Electrosprayed nanospherules, which provide improved solubility and bioavailability, are promising drug delivery tools for oral administration of poorly water-soluble fenofibrate. PMID:26834471

  18. Novel electrosprayed nanospherules for enhanced aqueous solubility and oral bioavailability of poorly water-soluble fenofibrate.

    PubMed

    Yousaf, Abid Mehmood; Mustapha, Omer; Kim, Dong Wuk; Kim, Dong Shik; Kim, Kyeong Soo; Jin, Sung Giu; Yong, Chul Soon; Youn, Yu Seok; Oh, Yu-Kyoung; Kim, Jong Oh; Choi, Han-Gon

    2016-01-01

    The purpose of the present research was to develop a novel electrosprayed nanospherule providing the most optimized aqueous solubility and oral bioavailability for poorly water-soluble fenofibrate. Numerous fenofibrate-loaded electrosprayed nanospherules were prepared with polyvinylpyrrolidone (PVP) and Labrafil(®) M 2125 as carriers using the electrospray technique, and the effect of the carriers on drug solubility and solvation was assessed. The solid state characterization of an optimized formulation was conducted by scanning electron microscopy, powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopic analyses. Oral bioavailability in rats was also evaluated for the formulation of an optimized nanospherule in comparison with free drug and a conventional fenofibrate-loaded solid dispersion. All of the electrosprayed nanospherule formulations had remarkably enhanced aqueous solubility and dissolution compared with free drug. Moreover, Labrafil M 2125, a surfactant, had a positive influence on the solubility and dissolution of the drug in the electrosprayed nanospherule. Increases were observed as the PVP/drug ratio increased to 4:1, but higher ratios gave no significant increases. In particular, an electrosprayed nanospherule composed of fenofibrate, PVP, and Labrafil M 2125 at the weight ratio of 1:4:0.5 resulted in a particle size of <200 nm with the drug present in the amorphous state. It demonstrated the highest solubility (32.51±2.41 μg/mL), an excellent dissolution (~85% in 10 minutes), and an oral bioavailability ~2.5-fold better than that of the free drug. It showed similar oral bioavailability compared to the conventional solid dispersion. Electrosprayed nanospherules, which provide improved solubility and bioavailability, are promising drug delivery tools for oral administration of poorly water-soluble fenofibrate.

  19. Eco-friendly luminescent solar concentrators with low reabsorption losses and resistance to concentration quenching based on aqueous-solution-processed thiolate-gold nanoclusters

    NASA Astrophysics Data System (ADS)

    Huang, H. Y.; Cai, K. B.; Chang, L. Y.; Chen, P. W.; Lin, T. N.; Lin, C. A. J.; Shen, J. L.; Talite, M. J.; Chou, W. C.; Yuan, C. T.

    2017-09-01

    Heavy-metal-containing quantum dots (QDs) with engineered electronic states have been served as luminophores in luminescent solar concentrators (LSCs) with impressive optical efficiency. Unfortunately, those QDs involve toxic elements and need to be synthesized in a hazardous solvent. Recently, biocompatible, eco-friendly gold nanoclusters (AuNCs), which can be directly synthesized in an aqueous solution, have gained much attention for promising applications in ‘green photonics’. Here, we explored the solid-state photophysical properties of aqueous-solution-processed, glutathione-stabilized gold nanoclusters (GSH-AuNCs) with a ligand-to-metal charge-transfer (LMCT) state for developing ‘green’ LSCs. We found that such GSH-AuNCs exhibit a large Stokes shift with almost no spectral overlap between the optical absorption and PL emission due to the LMCT states, thus, suppressing reabsorption losses. Compared with GSH-AuNCs in solution, the photoluminescence quantum yields (PL-QYs) of the LSCs can be enhanced, accompanied with a lengthened PL lifetime owing to the suppression of non-radiative recombination rates. In addition, the LSCs do not suffer from severe concentration-induced PL quenching, which is a common weakness for conventional luminophores. As a result, a common trade-off between light-harvesting efficiency and solid-state PL-QYs can be bypassed due to nearly-zero spectral overlap integral between the optical absorption and PL emission. We expect that GSH-AuNCs hold great promise for serving as luminophores for ‘green’ LSCs by further enhancing solid-state PL-QYs.

  20. Eco-friendly luminescent solar concentrators with low reabsorption losses and resistance to concentration quenching based on aqueous-solution-processed thiolate-gold nanoclusters.

    PubMed

    Huang, H Y; Cai, K B; Chang, L Y; Chen, P W; Lin, T N; Lin, C A J; Shen, J L; Talite, M J; Chou, W C; Yuan, C T

    2017-09-15

    Heavy-metal-containing quantum dots (QDs) with engineered electronic states have been served as luminophores in luminescent solar concentrators (LSCs) with impressive optical efficiency. Unfortunately, those QDs involve toxic elements and need to be synthesized in a hazardous solvent. Recently, biocompatible, eco-friendly gold nanoclusters (AuNCs), which can be directly synthesized in an aqueous solution, have gained much attention for promising applications in 'green photonics'. Here, we explored the solid-state photophysical properties of aqueous-solution-processed, glutathione-stabilized gold nanoclusters (GSH-AuNCs) with a ligand-to-metal charge-transfer (LMCT) state for developing 'green' LSCs. We found that such GSH-AuNCs exhibit a large Stokes shift with almost no spectral overlap between the optical absorption and PL emission due to the LMCT states, thus, suppressing reabsorption losses. Compared with GSH-AuNCs in solution, the photoluminescence quantum yields (PL-QYs) of the LSCs can be enhanced, accompanied with a lengthened PL lifetime owing to the suppression of non-radiative recombination rates. In addition, the LSCs do not suffer from severe concentration-induced PL quenching, which is a common weakness for conventional luminophores. As a result, a common trade-off between light-harvesting efficiency and solid-state PL-QYs can be bypassed due to nearly-zero spectral overlap integral between the optical absorption and PL emission. We expect that GSH-AuNCs hold great promise for serving as luminophores for 'green' LSCs by further enhancing solid-state PL-QYs.

  1. Compact Solid State Terahertz Detectors

    DTIC Science & Technology

    2007-07-09

    We think that the noise in our Be doped GaAs quantum well structures is of the shot noise origin as in conventional GaAs QWIPs designed for mid...University of Leeds as follows: Within the frame of this project attention will be focussed on the low-frequency noise of the proposed devices. More...specifically, the Johnson and shot noise , as well as 1/f noise spectra, will be measured at various temperatures from 4 K up to 300 K. The figure

  2. The 120V 20A PWM switch for applications in high power distribution

    NASA Astrophysics Data System (ADS)

    Borelli, V.; Nimal, W.

    1989-08-01

    A 20A/120VDC (voltage direct current) PWM (Pulse Width Modulation) Solid State Power Controller (SSPC) developed under ESA contract to be used in the power distribution system of Columbus is described. The general characteristics are discussed and the project specification defined. The benefits of a PWM solution over a more conventional approach, for the specific application considered are presented. An introduction to the SSPC characteristics and a functional description are presented.

  3. Microwave surface resistance of bulk YBa2Cu3O6+x material

    NASA Astrophysics Data System (ADS)

    Fathy, A.; Kalokitis, D.; Belohoubek, E.; Sundar, H. G. K.; Safari, A.

    1988-10-01

    Superconducting Y-Ba-Cu-O samples were prepared by conventional solid-state reaction. The microwave surface resistance of 1:2:3 compound superconductor material was measured in a special disk resonator structure at 10 GHz. At liquid-nitrogen temperatures the microwave surface resistance is comparable to that of Au. At lower temperature (~10 K) the surface resistance is an order of magnitude lower than that of Au at the same temperature.

  4. Threshold analysis of pulsed lasers with application to a room-temperature Co:MgF2 laser

    NASA Technical Reports Server (NTRS)

    Harrison, James; Welford, David; Moulton, Peter F.

    1989-01-01

    Rate-equation calculations are used to model accurately the near-threshold behavior of a Co:MgF2 laser operating at room temperature. The results demonstrate the limitations of the conventional threshold analysis in cases of practical interest. This conclusion is applicable to pulsed solid-state lasers in general. The calculations, together with experimental data, are used to determine emission cross sections for the Co:MgF2 laser.

  5. An Overview of Ni Base Additive Fabrication Technologies for Aerospace Applications (Preprint)

    DTIC Science & Technology

    2011-03-01

    fusion welding processes that have the ability to add filler material can be used as additive manufacturing processes . The majority of the work in the...Laser Additive Manufacturing (LAM) The LAM process uses a conventional laser welding heat source (CO2 or solid state laser) combined with a...wrought properties. The LAM process typically has a lower deposition rate (0.5 – 10 lbs/hr) compared to EB, PTA or TIG based processes , although as

  6. Generation of programmable temporal pulse shape and applications in micromachining

    NASA Astrophysics Data System (ADS)

    Peng, X.; Jordens, B.; Hooper, A.; Baird, B. W.; Ren, W.; Xu, L.; Sun, L.

    2009-02-01

    In this paper we presented a pulse shaping technique on regular solid-state lasers and the application in semiconductor micromachining. With a conventional Q-switched laser, all of the parameters can be adjusted over only limited ranges, especially the pulse width and pulse shape. However, some laser link processes using traditional laser pulses with pulse widths of a few nanoseconds to a few tens of nanoseconds tend to over-crater in thicker overlying passivation layers and thereby cause IC reliability problems. Use of a laser pulse with a special shape and a fast leading edge, such as tailored pulse, is one technique for controlling link processing. The pulse shaping technique is based on light-loop controlled optical modulation to shape conventional Q-switched solid-state lasers. One advantage of the pulse shaping technique is to provide a tailored pulse shape that can be programmed to have more than one amplitude value. Moreover, it has the capability of providing programmable tailored pulse shapes with discrete amplitude and time duration components. In addition, it provides fast rising and fall time of each pulse at fairly high repetition rate at 355nm with good beam quality. The regular-to-shaped efficiency is up to 50%. We conclude with a discussion of current results for laser processing of semiconductor memory link structures using programmable temporal pulse shapes. The processing experiments showed promising results with shaped pulse.

  7. 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

    NASA Astrophysics Data System (ADS)

    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 (<100 °C). Here, we comprehensively investigated the effects of non-coordinating solvent vapor on the properties of perovskite film, and obtained micron-sized columnar grains (with an average grain size of 1.4 μm) of CH3NH3PbI3 even at a low temperature of 75 °C when annealed with benzyl alcohol vapor. The perovskite 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.

  8. Embedding solar cell materials with on-board integrated energy storage for load-leveling and dark power delivery (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Pint, Cary L.; Westover, Andrew S.; Cohn, Adam P.; Erwin, William R.; Share, Keith; Metke, Thomas; Bardhan, Rizia

    2015-10-01

    This work will discuss our recent advances focused on integrating high power energy storage directly into the native materials of both conventional photovoltaics (PV) and dye-sensitized solar cells (DSSCs). In the first case (PV), we demonstrate the ability to etch high surface-area porous silicon charge storage interfaces directly into the backside of a conventional polycrystalline silicon photovoltaic device exhibiting over 14% efficiency. These high surface area materials are then coupled with solid-state ionic liquid-polymer electrolytes to produce solid-state fully integrated devices where the PV device can directly inject charge into an on-board supercapacitor that can be separately discharged under dark conditions with a Coulombic efficiency of 84%. In a similar manner, we further demonstrate that surface engineered silicon materials can be utilized to replace Pt counterelectrodes in conventional DSSC energy conversion devices. As the silicon counterelectrodes rely strictly on surface Faradaic chemical reactions with the electrolyte on one side of the wafer electrode, we demonstrate double-sided processing of electrodes that enables dual-function of the material for simultaneous energy storage and conversion, each on opposing sides. In both of these devices, we demonstrate the ability to produce an all-silicon coupled energy conversion and storage system through the common ability to convert unused silicon in solar cells into high power silicon-based supercapacitors. Beyond the proof-of-concept design and performance of this integrated solar-storage system, this talk will conclude with a brief discussion of the hurdles and challenges that we envision for this emerging area both from a fundamental and technological viewpoint.

  9. Semi-solid processing of high-chromium tool steel to obtain microstructures without carbide network

    NASA Astrophysics Data System (ADS)

    Jirková, H.; Aišman, D.; Rubešová, K.; Opatová, K.; Mašek, B.

    2017-02-01

    Treatment of high-alloy tool steels that involves transition to the semi-solid state can transform the sharp-edged primary carbides which usually form during solidification. These carbides severely impair toughness and are virtually impossible to eliminate by conventional treatment routes. Upon classical semi-solid processing which dissolves these carbides, the resulting microstructure consists of polyhedral and super-saturated austenite embedded in lamellar austenite-carbide network. This type of microstructure reflects in the mechanical properties, predominantly in material behaviour under tensile loading. Such a network, however, can be removed by appropriate thermomechanical treatment. In the present experiment, various procedures involving heating to the semi-solid state were tested on X210Cr12 tool steel. The feedstock was heated to the temperature range of 1220 - 1280 °C. The heating was followed by procedures involving either water quenching to the forming temperature, room temperature or temperature from the range from 500 °C to 1000 °C followed by reheating to the forming temperature. It was found that the development of the lamellar network strongly depends on the temperature of heating to semi-solid state. Thermomechanical treatment produced microstructures in which the matrix consisted of a mixture of polyhedral austenite grains and the M-A constituent. In addition, the initial lamellar eutectic network was partially or even completely melted and substituted with a mixture of very fine recrystallized austenite grains and precipitates of chromium carbides. Some fine M7C3 carbides were present in the austenitic-martensitic matrix as well. When appropriate processing parameters were chosen, very good mechanical properties were obtained, among them a hardness of 860 HV10.

  10. Fast probe of local electronic states in nanostructures utilizing a single-lead quantum dot

    PubMed Central

    Otsuka, Tomohiro; Amaha, Shinichi; Nakajima, Takashi; Delbecq, Matthieu R.; Yoneda, Jun; Takeda, Kenta; Sugawara, Retsu; Allison, Giles; Ludwig, Arne; Wieck, Andreas D.; Tarucha, Seigo

    2015-01-01

    Transport measurements are powerful tools to probe electronic properties of solid-state materials. To access properties of local electronic states in nanostructures, such as local density of states, electronic distribution and so on, micro-probes utilizing artificial nanostructures have been invented to perform measurements in addition to those with conventional macroscopic electronic reservoirs. Here we demonstrate a new kind of micro-probe: a fast single-lead quantum dot probe, which utilizes a quantum dot coupled only to the target structure through a tunneling barrier and fast charge readout by RF reflectometry. The probe can directly access the local electronic states with wide bandwidth. The probe can also access more electronic states, not just those around the Fermi level, and the operations are robust against bias voltages and temperatures. PMID:26416582

  11. Stable dye-sensitized solar cells based on a gel electrolyte with ethyl cellulose as the gelator

    NASA Astrophysics Data System (ADS)

    Vasei, Maryam; Tajabadi, Fariba; Jabbari, Ali; Taghavinia, Nima

    2015-09-01

    A simple gelating process is developed for the conventional acetonitrile-based electrolyte of dye solar cells, based on ethyl cellulose as the gelator. The electrolyte becomes quasi-solid-state upon addition of an ethanolic solution of ethyl cellulose to the conventional acetonitrile-based liquid electrolyte. The photovoltaic conversion efficiency with the new gel electrolyte is only slightly lower than with the liquid electrolyte, e.g., 6.5 % for liquid electrolyte versus 5.9 % for gel electrolyte with 5.8 wt% added ethyl cellulose. Electrolyte gelation has small effect on the ionic diffusion coefficient of iodide, and the devices are remarkably stable for at least 550 h under irradiation at 55 °C.

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hendon, Christopher H.; Rieth, Adam J.; Korzyński, Maciej D.

    Metal–organic frameworks (MOFs) allow compositional and structural diversity beyond conventional solid-state materials. Continued interest in the field is justified by potential applications of exceptional breadth, ranging from gas storage and separation, which takes advantage of the inherent pores and their volume, to electronic applications, which requires precise control of electronic structure. In this Outlook we present some of the pertinent challenges that MOFs face in their conventional implementations, as well as opportunities in less traditional areas. Here the aim is to discuss select design concepts and future research goals that emphasize nuances relevant to this class of materials as amore » whole. Particular emphasis is placed on synthetic aspects, as they influence the potential for MOFs in gas separation, electrical conductivity, and catalytic applications.« less

  13. Enhanced oral bioavailability of vinpocetine through mechanochemical salt formation: physico-chemical characterization and in vivo studies.

    PubMed

    Hasa, Dritan; Voinovich, Dario; Perissutti, Beatrice; Grassi, Mario; Bonifacio, Alois; Sergo, Valter; Cepek, Cinzia; Chierotti, Michele R; Gobetto, Roberto; Dall'Acqua, Stefano; Invernizzi, Sergio

    2011-08-01

    Enhancing oral bioavailability of vinpocetine by forming its amorphous citrate salt through a solvent-free mechanochemical process, in presence of micronised crospovidone and citric acid. The impact of formulation and process variables (amount of polymer and citric acid, and milling time) on vinpocetine solubilization kinetics from the coground was studied through an experimental design. The best performing samples were characterized by employing a multidisciplinary approach, involving Differential scanning calorimetry, X-ray diffraction, Raman imaging/spectroscopy, X-ray photoelectron spectroscopy, solid-state NMR spectroscopy, porosimetry and in vivo studies on rats to ascertain the salt formation, their solid-state characteristics and oral bioavailability in comparison to vinpocetine citrate salt (Oxopocetine(®)). The analyses attested that the mechanochemical process is a viable way to produce in absence of solvents vinpocetine citrate salt in an amorphous state. From the in vivo studies on rats the obtained salt was four times more bioavailable than its physical mixture and bioequivalent to the commercial salt produced by conventional synthetic process implying the use of solvent.

  14. Real-time assessment of critical quality attributes of a continuous granulation process.

    PubMed

    Fonteyne, Margot; Vercruysse, Jurgen; Díaz, Damián Córdoba; Gildemyn, Delphine; Vervaet, Chris; Remon, Jean Paul; De Beer, Thomas

    2013-02-01

    There exists the intention to shift pharmaceutical manufacturing of solid dosage forms from traditional batch production towards continuous production. The currently applied conventional quality control systems, based on sampling and time-consuming off-line analyses in analytical laboratories, would annul the advantages of continuous processing. It is clear that real-time quality assessment and control is indispensable for continuous production. This manuscript evaluates strengths and weaknesses of several complementary Process Analytical Technology (PAT) tools implemented in a continuous wet granulation process, which is part of a fully continuous from powder-to-tablet production line. The use of Raman and NIR-spectroscopy and a particle size distribution analyzer is evaluated for the real-time monitoring of critical parameters during the continuous wet agglomeration of an anhydrous theophylline- lactose blend. The solid state characteristics and particle size of the granules were analyzed in real-time and the critical process parameters influencing these granule characteristics were identified. The temperature of the granulator barrel, the amount of granulation liquid added and, to a lesser extent, the powder feed rate were the parameters influencing the solid state of the active pharmaceutical ingredient (API). A higher barrel temperature and a higher powder feed rate, resulted in larger granules.

  15. Pushing the Theoretical Limit of Li-CFx Batteries: A Tale of Bi-functional Electrolyte

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rangasamy, Ezhiylmurugan; Li, Juchuan; Sahu, Gayatri

    2014-01-01

    In a typical battery, electrodes deliver capacities less or equal the theoretical maxima of the electrode materials.1 The inert electrolyte functions solely as the ionic conductor without contribution to the cell capacity because of its distinct mono-function in the concept of conventional batteries. Here we demonstrate that the most energy-dense Li-CFx battery2 delivers a capacity exceeding the theoretical maximum of CFx with a solid electrolyte of Li3PS4 (LPS) that has dual functions: as the inert electrolyte at the anode and the active component at the cathode. Such a bi-functional electrolyte reconciles both inert and active characteristics through a synergistic dischargemore » mechanism of CFx and LPS. Li3PS4 is known as an inactive solid electrolyte with a broad electrochemical window over 5 V.3 The synergy at the cathode is through LiF, the discharge product of CFx, which activates the electrochemical discharge of LPS at a close electrochemical potential of CFx. Therefore, the solid-state Li-CFx batteries output 126.6% energy beyond their theoretic limits without compromising the stability of the cell voltage. The extra energy comes from the electrochemical discharge of LPS, the inert electrolyte. This bi-functional electrolyte revolutionizes the concept of conventional batteries and opens a new avenue for the design of batteries with an unprecedentedly high energy density.« less

  16. Coiled transmission line pulse generators

    DOEpatents

    McDonald, Kenneth Fox

    2010-11-09

    Methods and apparatus are provided for fabricating and constructing solid dielectric "Coiled Transmission Line" pulse generators in radial or axial coiled geometries. The pour and cure fabrication process enables a wide variety of geometries and form factors. The volume between the conductors is filled with liquid blends of monomers, polymers, oligomers, and/or cross-linkers and dielectric powders; and then cured to form high field strength and high dielectric constant solid dielectric transmission lines that intrinsically produce ideal rectangular high voltage pulses when charged and switched into matched impedance loads. Voltage levels may be increased by Marx and/or Blumlein principles incorporating spark gap or, preferentially, solid state switches (such as optically triggered thyristors) which produce reliable, high repetition rate operation. Moreover, these Marxed pulse generators can be DC charged and do not require additional pulse forming circuitry, pulse forming lines, transformers, or an a high voltage spark gap output switch. The apparatus accommodates a wide range of voltages, impedances, pulse durations, pulse repetition rates, and duty cycles. The resulting mobile or flight platform friendly cylindrical geometric configuration is much more compact, light-weight, and robust than conventional linear geometries, or pulse generators constructed from conventional components. Installing additional circuitry may accommodate optional pulse shape improvements. The Coiled Transmission Lines can also be connected in parallel to decrease the impedance, or in series to increase the pulse length.

  17. Study on ABO and RhD blood grouping: Comparison between conventional tile method and a new solid phase method (InTec Blood Grouping Test Kit).

    PubMed

    Yousuf, R; Abdul Ghani, S A; Abdul Khalid, N; Leong, C F

    2018-04-01

    'InTec Blood Grouping Test kit' using solid-phase technology is a new method which may be used at outdoor blood donation site or at bed side as an alternative to the conventional tile method in view of its stability at room temperature and fulfilled the criteria as point of care test. This study aimed to compare the efficiency of this solid phase method (InTec Blood Grouping Test Kit) with the conventional tile method in determining the ABO and RhD blood group of healthy donors. A total of 760 voluntary donors who attended the Blood Bank, Penang Hospital or offsite blood donation campaigns from April to May 2014 were recruited. The ABO and RhD blood groups were determined by the conventional tile method and the solid phase method, in which the tube method was used as the gold standard. For ABO blood grouping, the tile method has shown 100% concordance results with the gold standard tube method, whereas the solid-phase method only showed concordance result for 754/760 samples (99.2%). Therefore, for ABO grouping, tile method has 100% sensitivity and specificity while the solid phase method has slightly lower sensitivity of 97.7% but both with good specificity of 100%. For RhD grouping, both the tile and solid phase methods have grouped one RhD positive specimen as negative each, thus giving the sensitivity and specificity of 99.9% and 100% for both methods respectively. The 'InTec Blood Grouping Test Kit' is suitable for offsite usage because of its simplicity and user friendliness. However, further improvement in adding the internal quality control may increase the test sensitivity and validity of the test results.

  18. Electron tunneling in nanoscale electrodes for battery applications

    NASA Astrophysics Data System (ADS)

    Yamada, Hidenori; Narayanan, Rajaram; Bandaru, Prabhakar R.

    2018-03-01

    It is shown that the electrical current that may be obtained from a nanoscale electrochemical system is sensitive to the dimensionality of the electrode and the density of states (DOS). Considering the DOS of lower dimensional systems, such as two-dimensional graphene, one-dimensional nanotubes, or zero-dimensional quantum dots, yields a distinct variation of the current-voltage characteristics. Such aspects go beyond conventional Arrhenius theory based kinetics which are often used in experimental interpretation. The obtained insights may be adapted to other devices, such as solid-state batteries. It is also indicated that electron transport in such devices may be considered through electron tunneling.

  19. Optically powered remote gas monitor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dubaniewicz, T.H. Jr.; Chilton, J.E.

    1995-12-31

    Many mines rely on toxic gas sensors to help maintain a safe and healthy work environment. This report describes a prototype monitoring system developed by the US Bureau of Mines (USBM) that uses light to power and communicate with several remote toxic gas sensors. The design is based on state-of-art optical-to-electrical power converters, solid-state diode lasers, and fiber optics. This design overcomes several problems associated with conventional wire-based systems by providing complete electrical isolation between the remote sensors and the central monitor. The prototype performed well during a 2-week field trial in the USBM Pittsburgh Research Center Safety Research Coalmore » Mine.« less

  20. Synthesis, structural and semiconducting properties of Ba(Cu1/3 Sb2/3)O3-PbTiO3 solid solutions

    NASA Astrophysics Data System (ADS)

    Singh, Chandra Bhal; Kumar, Dinesh; Prashant, Verma, Narendra Kumar; Singh, Akhilesh Kumar

    2018-05-01

    We report the synthesis and properties of a new solid solution 0.05Ba(Cu1/3Sb2/3)O3-0.95PbTiO3 (BCS-PT) which shows the semiconducting properties. In this study, we have designed new perovskite-type (ABO3) solid solution of BCS-PT that have tunable optical band gap. BCS-PT compounds were prepared by conventional solid-state reaction method and their structural, micro-structural and optical properties were analyzed. The calcination temperature for BCS-PT solid solutions has been optimized to obtain a phase pure system. The Reitveld analysis of X-ray data show that all samples crystallize in tetragonal crystal structure with space group P4mm. X-ray investigation revealed that increase in calcination temperature led to increase of lattice parameter `a' while `c' parameter value lowered. The band gap of PbTiO3 is reduced from 3.2 eV to 2.8 eV with BCS doping and with increasing calcination temperature it further reduces to 2.56 eV. The reduced band gap indicated that the compounds are semiconducting and can be used for photovoltaic device applications.

  1. Lubrication with solids.

    NASA Technical Reports Server (NTRS)

    Buckley, D. H.; Johnson, R. L.

    1972-01-01

    Brief discussion of the historical background, variety range, chemistry, physics, and other properties of solid lubricants, and review of their current uses. The widespread use of solid lubricants did not occur until about 1947. At present, they are the object of such interest that a special international conference on their subject was held in 1971. They are used at temperatures beyond the useful range of conventional lubricating oils and greases. Their low volatility provides them with the capability of functioning effectively in vacuum and invites their use in space applications. Their high load carrying ability makes them useful with heavily loaded components. Solid lubricants, however, do lack some of the desirable properties of conventional lubricants. Unlike oils and greases, which have fluidity and can continuously be carried back into contact with lubricated surfaces, solid lubricants, because of their immobility, have finite lives. Also, oils and greases can carry away frictional heat from contacting surfaces, while solid lubricants cannot.

  2. Surpassing the Theoretical Limit of Porosity in Conventional Solid-State Foaming: Microstructure Characterization of Length Scales in a Copper Metal Foam

    DTIC Science & Technology

    2014-11-01

    powder metallurgy processes (e.g., using a polymer foam as a fugitive template7) can exceed 85% porosity, it is more common for powder metallurgy ...for the 0.5 GPa compact is a remarkable result from a powder metallurgy process, especially because the pore structure is not dominated by necks...strengths in bulk engineering structures produced via powder metallurgy . Completely unique to this process is the ability to create foamed powder . This

  3. Designed synthesis and stacking architecture of solid and mesoporous TiO(2) nanoparticles for enhancing the light-harvesting efficiency of dye-sensitized solar cells.

    PubMed

    Ahn, Ji Young; Moon, Kook Joo; Kim, Ji Hoon; Lee, Sang Hyun; Kang, Jae Wook; Lee, Hyung Woo; Kim, Soo Hyung

    2014-01-22

    We fabricated solid and mesoporous TiO2 nanoparticles (NPs) with relatively large primary sizes of approximately 200 nm via inorganic templates for aero-sol-gel and subsequent aqueous-washing processes. The amount of dye molecules adsorbed by the internal pores in the mesoporous TiO2 NPs was increased by creating the nanopores within the solid TiO2 NPs. Simultaneously, the light-scattering effect of the mesoporous TiO2 NPs fabricated by this approach was secured by maintaining their spherical shape and relatively large average size. By precisely accumulating the fabricated solid or mesoporous 200 nm diameter TiO2 NPs on top of a conventional 25 nm diameter TiO2 NP-based underlayer, we could systematically examine the effect of the solid and mesoporous TiO2 NPs on the photovoltaic performance of dye-sensitized solar cells (DSSCs). Consequently, the stacking architecture of the mesoporous TiO2 NP-based overlayer, which functioned as both a light-scattering and dye-supporting medium, on top of a conventional solid TiO2 NP-based underlayer in a DSSC photoelectrode (i.e., double-layer structures) was found to be very promising for significantly improving the photovoltaic properties of conventional solid TiO2 NP single-layer-based DSSCs.

  4. Solid-state laser pumping with a planar compound parabolic concentrator.

    PubMed

    Panteli, D V; Pani, B M; Beli, L Z

    1997-10-20

    A novel solid-state laser-pumping scheme is proposed that combines a reflective lamp chamber and a compound parabolic concentrator (CPC) as a light guide. The CPC is made of a transparent material of high refractive index, and light is guided by the total internal reflection, with drastically reduced reflection losses. Material is chosen so that the absorption losses are minimized in the pumping wavelength range. The lamp chamber is designed with the principles of nonimaging optics, which ensures that the radiation is efficiently transferred from the lamp to the input aperture of the CPC. The pumping efficiency was first estimated theoretically, which gave us enough justification for the more accurate calculations with ray tracing. Single as well as multiple pumping cavities are discussed. New pumping geometry results in significantly increased pumping efficiency compared with conventional geometries. Also the lamp and the laser rod are separated, leading to reduced thermal load. We found that the proposed pumping method is also applicable to diode-pumped lasers.

  5. Single Benzene Green Fluorophore: Solid-State Emissive, Water-Soluble, and Solvent- and pH-Independent Fluorescence with Large Stokes Shifts.

    PubMed

    Beppu, Teruo; Tomiguchi, Kosuke; Masuhara, Akito; Pu, Yong-Jin; Katagiri, Hiroshi

    2015-06-15

    Benzene is the simplest aromatic hydrocarbon with a six-membered ring. It is one of the most basic structural units for the construction of π conjugated systems, which are widely used as fluorescent dyes and other luminescent materials for imaging applications and displays because of their enhanced spectroscopic signal. Presented herein is 2,5-bis(methylsulfonyl)-1,4-diaminobenzene as a novel architecture for green fluorophores, established based on an effective push-pull system supported by intramolecular hydrogen bonding. This compound demonstrates high fluorescence emission and photostability and is solid-state emissive, water-soluble, and solvent- and pH-independent with quantum yields of Φ=0.67 and Stokes shift of 140 nm (in water). This architecture is a significant departure from conventional extended π-conjugated systems based on a flat and rigid molecular design and provides a minimum requirement for green fluorophores comprising a single benzene ring. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Atomic Scale Dynamics of Contact Formation in the Cross-Section of InGaAs Nanowire Channels

    DOE PAGES

    Chen, Renjie; Jungjohann, Katherine L.; Mook, William M.; ...

    2017-03-23

    In the alloyed and compound contacts between metal and semiconductor transistor channels we see that they enable self-aligned gate processes which play a significant role in transistor scaling. At nanoscale dimensions and for nanowire channels, prior experiments focused on reactions along the channel length, but the early stage of reaction in their cross sections remains unknown. We report on the dynamics of the solid-state reaction between metal (Ni) and semiconductor (In 0.53Ga 0.47As), along the cross-section of nanowires that are 15 nm in width. Unlike planar structures where crystalline nickelide readily forms at conventional, low alloying temperatures, nanowires exhibit amore » solid-state amorphization step that can undergo a crystal regrowth step at elevated temperatures. Here, we capture the layer-by-layer reaction mechanism and growth rate anisotropy using in situ transmission electron microscopy (TEM). Our kinetic model depicts this new, in-plane contact formation which could pave the way for engineered nanoscale transistors.« less

  7. DNP-enhanced ultrawideline solid-state NMR spectroscopy: Studies of platinum in metal–organic frameworks

    DOE PAGES

    Kobayashi, Takeshi; Perras, Frederic A.; Goh, Tian Wei; ...

    2016-06-06

    Ultrawideline dynamic nuclear polarization (DNP)-enhanced 195Pt solid-state NMR (SSNMR) spectroscopy and theoretical calculations are used to determine the coordination of atomic Pt species supported within the pores of metal–organic frameworks (MOFs). The 195Pt SSNMR spectra, with breadths reaching 10,000 ppm, were obtained by combining DNP with broadbanded cross-polarization and CPMG acquisition. Although the DNP enhancements in static samples are lower than those typically observed under magic-angle spinning conditions, the presented measurements would be very challenging using the conventional SSNMR methods. The DNP-enhanced ultrawideline NMR spectra served to separate signals from cis- and trans-coordinated atomic Pt 2+ species supported on themore » UiO-66-NH 2 MOF. Here, the data revealed a dominance of kinetic effects in the formation of Pt 2+ complexes and the thermodynamic effects in their reduction to nanoparticles. A single cis-coordinated Pt 2+ complex was confirmed in MOF-253.« less

  8. Solid State pH Sensor Based on Light Emitting Diodes (LED) As Detector Platform

    PubMed Central

    Lau, King Tong; Shepherd, R.; Diamond, Danny; Diamond, Dermot

    2006-01-01

    A low-power, high sensitivity, very low-cost light emitting diode (LED)-based device developed for low-cost sensor networks was modified with bromocresol green membrane to work as a solid-state pH sensor. In this approach, a reverse-biased LED functioning as a photodiode is coupled with a second LED configured in conventional emission mode. A simple timer circuit measures how long (in microsecond) it takes for the photocurrent generated on the detector LED to discharge its capacitance from logic 1 (+5 V) to logic 0 (+1.7 V). The entire instrument provides an inherently digital output of light intensity measurements for a few cents. A light dependent resistor (LDR) modified with similar sensor membrane was also used as a comparison method. Both the LED sensor and the LDR sensor responded to various pH buffer solutions in a similar way to obtain sigmoidal curves expected of the dye. The pKa value obtained for the sensors was found to agree with the literature value.

  9. A Solid State Pyranometer

    NASA Astrophysics Data System (ADS)

    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.

  10. Formation of 1.4 MeV runaway electron flows in air using a solid-state generator with 10 MV/ns voltage rise rate

    NASA Astrophysics Data System (ADS)

    Mesyats, G. A.; Pedos, M. S.; Rukin, S. N.; Rostov, V. V.; Romanchenko, I. V.; Sadykova, A. G.; Sharypov, K. A.; Shpak, V. G.; Shunailov, S. A.; Ul'masculov, M. R.; Yalandin, M. I.

    2018-04-01

    Fulfillment of the condition that the voltage rise time across an air gap is comparable with the time of electron acceleration from a cathode to an anode allows a flow of runaway electrons (REs) to be formed with relativistic energies approaching that determined by the amplitude of the voltage pulse. In the experiment described here, an RE energy of 1.4 MeV was observed by applying a negative travelling voltage pulse of 860-kV with a maximum rise rate of 10 MV/ns and a rise time of 100-ps. The voltage pulse amplitude was doubled at the cathode of the 2-cm-long air gap due to the delay of conventional pulsed breakdown. The above-mentioned record-breaking voltage pulse of ˜120 ps duration with a peak power of 15 GW was produced by an all-solid-state pulsed power source utilising pulse compression/sharpening in a multistage gyromagnetic nonlinear transmission line.

  11. Using Solid State Drives as a Mid-Tier Cache in Enterprise Database OLTP Applications

    NASA Astrophysics Data System (ADS)

    Khessib, Badriddine M.; Vaid, Kushagra; Sankar, Sriram; Zhang, Chengliang

    When originally introduced, flash based solid state drives (SSD) exhibited a very high random read throughput with low sub-millisecond latencies. However, in addition to their steep prices, SSDs suffered from slow write rates and reliability concerns related to cell wear. For these reasons, they were relegated to a niche status in the consumer and personal computer market. Since then, several architectural enhancements have been introduced that led to a substantial increase in random write operations as well as a reasonable improvement in reliability. From a purely performance point of view, these high I/O rates and improved reliability make the SSDs an ideal choice for enterprise On-Line Transaction Processing (OLTP) applications. However, from a price/performance point of view, the case for SSDs may not be clear. Enterprise class SSD Price/GB, continues to be at least 10x higher than conventional magnetic hard disk drives (HDD) despite considerable drop in Flash chip prices.

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

    NASA Astrophysics Data System (ADS)

    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.

  13. Visualization of electrochemically driven solid-state phase transformations using operando hard X-ray spectro-imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Linsen; Chen-Wiegart, Yu-chen Karen; Wang, Jiajun

    In situ techniques with high temporal, spatial and chemical resolution are key to understand ubiquitous solid-state phase transformations, which are crucial to many technological applications. Hard X-ray spectro-imaging can visualize electrochemically driven phase transformations but demands considerably large samples with strong absorption signal so far. Here we show a conceptually new data analysis method to enable operando visualization of mechanistically relevant weakly absorbing samples at the nanoscale and study electrochemical reaction dynamics of iron fluoride, a promising high-capacity conversion cathode material. In two specially designed samples with distinctive microstructure and porosity, we observe homogeneous phase transformations during both discharge andmore » charge, faster and more complete Li-storage occurring in porous polycrystalline iron fluoride, and further, incomplete charge reaction following a pathway different from conventional belief. In conclusion, these mechanistic insights provide guidelines for designing better conversion cathode materials to realize the promise of high-capacity lithium-ion batteries.« less

  14. Visualization of electrochemically driven solid-state phase transformations using operando hard X-ray spectro-imaging

    DOE PAGES

    Li, Linsen; Chen-Wiegart, Yu-chen Karen; Wang, Jiajun; ...

    2015-04-20

    In situ techniques with high temporal, spatial and chemical resolution are key to understand ubiquitous solid-state phase transformations, which are crucial to many technological applications. Hard X-ray spectro-imaging can visualize electrochemically driven phase transformations but demands considerably large samples with strong absorption signal so far. Here we show a conceptually new data analysis method to enable operando visualization of mechanistically relevant weakly absorbing samples at the nanoscale and study electrochemical reaction dynamics of iron fluoride, a promising high-capacity conversion cathode material. In two specially designed samples with distinctive microstructure and porosity, we observe homogeneous phase transformations during both discharge andmore » charge, faster and more complete Li-storage occurring in porous polycrystalline iron fluoride, and further, incomplete charge reaction following a pathway different from conventional belief. In conclusion, these mechanistic insights provide guidelines for designing better conversion cathode materials to realize the promise of high-capacity lithium-ion batteries.« less

  15. A stable perovskite electrolyte in moist air for Li-ion batteries.

    PubMed

    Li, Yutao; Xu, Henghui; Chien, Po-Hsiu; Wu, Nan; Xin, Sen; Xue, Leigang; Park, Kyusung; Hu, Yan-Yan; Goodenough, John B

    2018-05-07

    Solid-oxide Li+ electrolytes of a rechargeable cell are generally sensitive to moisture in the air, H+ exchanges for the mobile Li+ of the electrolyte and forms insulating surface phases at the electrolyte interfaces and in the grain boundaries of a polycrystalline membrane. These surface phases dominate the total interfacial resistance of a conventional rechargeable cell having a solid-electrolyte separator. We report a new perovskite Li+ solid electrolyte, Li0.38Sr0.44Ta0.7Hf0.3O2.95F0.05, having a Li-ion conductivity σLi = 4.8×10-4 S cm-1 at 25 oC that does not react with water having 3≤pH≤14. The solid electrolyte with a thin Li+-conducting polymer on its surface to prevent reduction of Ta5+ is wet by metallic lithium and provides low-impedance dendrite-free plating/stripping of a lithium anode. It is also stable on contact with a composite polymer cathode. With this solid electrolyte, we demonstrate excellent cycling performance of an all-solid-state Li/LiFePO4 cell, a Li-S cell with a polymer-gel cathode, and a supercapacitor. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Flexible, solid-state, ion-conducting membrane with 3D garnet nanofiber networks for lithium batteries

    PubMed Central

    Fu, Kun (Kelvin); Gong, Yunhui; Dai, Jiaqi; Gong, Amy; Han, Xiaogang; Yao, Yonggang; Wang, Chengwei; Wang, Yibo; Chen, Yanan; Yan, Chaoyi; Li, Yiju; Wachsman, Eric D.; Hu, Liangbing

    2016-01-01

    Beyond state-of-the-art lithium-ion battery (LIB) technology with metallic lithium anodes to replace conventional ion intercalation anode materials is highly desirable because of lithium’s highest specific capacity (3,860 mA/g) and lowest negative electrochemical potential (∼3.040 V vs. the standard hydrogen electrode). In this work, we report for the first time, to our knowledge, a 3D lithium-ion–conducting ceramic network based on garnet-type Li6.4La3Zr2Al0.2O12 (LLZO) lithium-ion conductor to provide continuous Li+ transfer channels in a polyethylene oxide (PEO)-based composite. This composite structure further provides structural reinforcement to enhance the mechanical properties of the polymer matrix. The flexible solid-state electrolyte composite membrane exhibited an ionic conductivity of 2.5 × 10−4 S/cm at room temperature. The membrane can effectively block dendrites in a symmetric Li | electrolyte | Li cell during repeated lithium stripping/plating at room temperature, with a current density of 0.2 mA/cm2 for around 500 h and a current density of 0.5 mA/cm2 for over 300 h. These results provide an all solid ion-conducting membrane that can be applied to flexible LIBs and other electrochemical energy storage systems, such as lithium–sulfur batteries. PMID:27307440

  17. Hydrothermal preparation of blue molybdenum bronze nanoribbons: structural changes in mother crystals, related to solid-state conversion and crystallite splitting to nanomorphology

    NASA Astrophysics Data System (ADS)

    Nishida, Takamasa; Eda, Kazuo

    2018-02-01

    Hydrothermal syntheses of alkali-metal blue molybdenum bronze nanoribbons, which are expected to exhibit unique properties induced by a combined effect of extrinsic and intrinsic low-dimensionalities, from hydrated-alkali-metal molybdenum bronzes were investigated. Nanoribbons grown along the quasi-one-dimensional (1D) conductive direction of Cs0.3MoO3, which is difficult to prepare by the conventional methods, were first synthesized. The nanomorphology formation is achieved by a solid-state conversion (or crystallite splitting) and subsequent crystallite growth, and the structural changes of the starting material related to the conversion were first observed by powder X-ray diffraction and scanning transmission electron microscopy as a result of finely tuned reaction system and preparation conditions. The structural changes were analyzed by model simulations and were attributed to the structural modulations that were concerned with the intralayer packing disorder and with two-dimensional long-range ordered structure, formed in MoO3 sheets of the hydrated molybdenum bronze. Moreover, the modulations were related to displacement defects of the Mo-O framework units generated along the [100] direction in the hydrated molybdenum bronze. Then, it was suggested that the solid-state conversion into blue molybdenum bronze and the crystallite splitting to nanomorphology were initiated by the breaking of the Mo-O-Mo bonds at the defects. [Figure not available: see fulltext.

  18. Cobalt terephthalate MOF-templated synthesis of porous nano-crystalline Co3O4 by the new indirect solid state thermolysis as cathode material of asymmetric supercapacitor

    NASA Astrophysics Data System (ADS)

    Bigdeli, Hadise; Moradi, Morteza; Hajati, Shaaker; Kiani, Mohammad Ali; Toth, Jozsef

    2017-10-01

    In this work, two different types of Co3O4 nano-crystals were synthesized by (i) conventional direct solid state thermolysis of cobalt terephthalate metal-organic framework (MOF-71) and (ii) new indirect solid state thermolysis of Co(OH)2 derived by alkaline aqueous treatment of MOF-71. The products were then characterized by X-ray diffraction technique (XRD), Fourier transforms infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Reflection electron energy loss spectroscopy (REELS), Brunauer, Emmett, and Teller (BET), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) techniques. By REELS analysis the energy band gap of MOF-71 was determined to be 3.7 eV. Further, electrochemical performance of each Co3O4 nanostructure was studied by the cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) in a three-electrode system in KOH electrolyte. An asymmetric supercapacitor was fabricated using indirect Co3O4 nanoparticles as cathode and electrochemically reduced graphene oxide as anode, and the electrochemical properties were studied and showed a high energy density of 13.51 Wh kg-1 along with a power density of 9775 W kg-1 and good cycling stability with capacitance retention rate of 85% after 2000 cycles.

  19. Flexible, solid-state, ion-conducting membrane with 3D garnet nanofiber networks for lithium batteries

    NASA Astrophysics Data System (ADS)

    Kun, Kelvin; Gong, Yunhui; Dai, Jiaqi; Gong, Amy; Han, Xiaogang; Yao, Yonggang; Wang, Chengwei; Wang, Yibo; Chen, Yanan; Yan, Chaoyi; Li, Yiju; Wachsman, Eric D.; Hu, Liangbing

    2016-06-01

    Beyond state-of-the-art lithium-ion battery (LIB) technology with metallic lithium anodes to replace conventional ion intercalation anode materials is highly desirable because of lithium's highest specific capacity (3,860 mA/g) and lowest negative electrochemical potential (˜3.040 V vs. the standard hydrogen electrode). In this work, we report for the first time, to our knowledge, a 3D lithium-ion-conducting ceramic network based on garnet-type Li6.4La3Zr2Al0.2O12 (LLZO) lithium-ion conductor to provide continuous Li+ transfer channels in a polyethylene oxide (PEO)-based composite. This composite structure further provides structural reinforcement to enhance the mechanical properties of the polymer matrix. The flexible solid-state electrolyte composite membrane exhibited an ionic conductivity of 2.5 × 10-4 S/cm at room temperature. The membrane can effectively block dendrites in a symmetric Li | electrolyte | Li cell during repeated lithium stripping/plating at room temperature, with a current density of 0.2 mA/cm2 for around 500 h and a current density of 0.5 mA/cm2 for over 300 h. These results provide an all solid ion-conducting membrane that can be applied to flexible LIBs and other electrochemical energy storage systems, such as lithium-sulfur batteries.

  20. Ultrafiltration of thin stillage from conventional and e-mill dry grind processes.

    PubMed

    Arora, Amit; Dien, Bruce S; Belyea, Ronald L; Wang, Ping; Singh, Vijay; Tumbleson, M E; Rausch, Kent D

    2011-05-01

    We used ultrafiltration (UF) to evaluate membrane filtration characteristics of thin stillage and determine solids and nutrient compositions of filtered streams. To obtain thin stillage, corn was fermented using laboratory methods. UF experiments were conducted in batch mode under constant temperature and flow rate conditions. Two regenerated cellulose membranes (10 and 100 kDa molecular weight cutoffs) were evaluated with the objective of retaining solids as well as maximizing permeate flux. Optimum pressures for 10 and 100 kDa membranes were 207 and 69 kPa, respectively. Total solids, ash, and neutral detergent fiber contents of input TS streams of dry grind and E-Mill processes were similar; however, fat and protein contents were different (p < 0.05). Retentate obtained from conventional thin stillage fractionation had higher mean total solids contents (27.6% to 27.8%) compared to E-Mill (22.2% to 23.4%). Total solids in retentate streams were found similar to those from commercial evaporators used in industry (25% to 35% total solids). Fat contents of retentate streams ranged from 16.3% to 17.5% for the conventional process. A 2% increment in fat concentration was observed in the E-Mill retentate stream. Thin stillage ash content was reduced 60% in retentate streams.

  1. Research study on multi-KW-DC distribution system

    NASA Technical Reports Server (NTRS)

    Berkery, E. A.; Krausz, A.

    1975-01-01

    A detailed definition of the HVDC test facility and the equipment required to implement the test program are provided. The basic elements of the test facility are illustrated, and consist of: the power source, conventional and digital supervision and control equipment, power distribution harness and simulated loads. The regulated dc power supplies provide steady-state power up to 36 KW at 120 VDC. Power for simulated line faults will be obtained from two banks of 90 ampere-hour lead-acid batteries. The relative merits of conventional and multiplexed power control will be demonstrated by the Supervision and Monitor Unit (SMU) and the Automatically Controlled Electrical Systems (ACES) hardware. The distribution harness is supported by a metal duct which is bonded to all component structures and functions as the system ground plane. The load banks contain passive resistance and reactance loads, solid state power controllers and active pulse width modulated loads. The HVDC test facility is designed to simulate a power distribution system for large aerospace vehicles.

  2. Electrode-Electrolyte Interfaces in Lithium-Sulfur Batteries with Liquid or Inorganic Solid Electrolytes.

    PubMed

    Yu, Xingwen; Manthiram, Arumugam

    2017-11-21

    Electrode-electrolyte interfacial properties play a vital role in the cycling performance of lithium-sulfur (Li-S) batteries. The issues at an electrode-electrolyte interface include electrochemical and chemical reactions occurring at the interface, formation mechanism of interfacial layers, compositional/structural characteristics of the interfacial layers, ionic transport across the interface, and thermodynamic and kinetic behaviors at the interface. Understanding the above critical issues is paramount for the development of strategies to enhance the overall performance of Li-S batteries. Liquid electrolytes commonly used in Li-S batteries bear resemblance to those employed in traditional lithium-ion batteries, which are generally composed of a lithium salt dissolved in a solvent matrix. However, due to a series of unique features associated with sulfur or polysulfides, ether-based solvents are generally employed in Li-S batteries rather than simply adopting the carbonate-type solvents that are generally used in the traditional Li + -ion batteries. In addition, the electrolytes of Li-S batteries usually comprise an important additive, LiNO 3 . The unique electrolyte components of Li-S batteries do not allow us to directly take the interfacial theories of the traditional Li + -ion batteries and apply them to Li-S batteries. On the other hand, during charging/discharging a Li-S battery, the dissolved polysulfide species migrate through the battery separator and react with the Li anode, which magnifies the complexity of the interfacial problems of Li-S batteries. However, current Li-S battery development paths have primarily been energized by advances in sulfur cathodes. Insight into the electrode-electrolyte interfacial behaviors has relatively been overshadowed. In this Account, we first examine the state-of-the-art contributions in understanding the solid-electrolyte interphase (SEI) formed on the Li-metal anode and sulfur cathode in conventional liquid-electrolyte Li-S batteries and how the resulting chemical and physical properties of the SEI affect the overall battery performance. A few strategies recently proposed for improving the stability of SEI are briefly summarized. Solid Li + -ion conductive electrolytes have been attempted for the development of Li-S batteries to eliminate the polysulfide shuttle issues. One approach is based on a concept of "all-solid-state Li-S battery," in which all the cell components are in the solid state. Another approach is based on a "hybrid-electrolyte Li-S battery" concept, in which the solid electrolyte plays roles both as a Li + -ion conductor for the electrochemical reaction and as a separator to prevent polysulfide shuttle. However, these endeavors with the solid electrolyte are not able to provide an overall satisfactory cell performance. In addition to the low ionic conductivity of solid-state electrolytes, a critical issue lies in the poor interfacial properties between the electrode and the solid electrolyte. This Account provides a survey of the relevant research progress in understanding and manipulating the interfaces of electrode and solid electrolytes in both the "all-solid-state Li-S batteries" and the "hybrid-electrolyte Li-S batteries". A recently proposed "semi-solid-state Li-S battery" concept is also briefly discussed. Finally, future research and development directions in all the above areas are suggested.

  3. Ultrastructural changes of sheep cumulus-oocyte complexes following different methods of vitrification.

    PubMed

    Ebrahimi, Bita; Valojerdi, Mojtaba Rezazadeh; Eftekhari-Yazdi, Poopak; Baharvand, Hossein

    2012-05-01

    To determine the ultrastructural changes of sheep cumulus-oocyte complexes (COCs) following different methods of vitrification, good quality isolated COCs (GV stage) were randomly divided into the non-vitrified control, conventional straw, cryotop and solid surface vitrification groups. In both conventional and cryotop methods, vitrified COCs were respectively loaded by conventional straws and cryotops, and then plunged directly into liquid nitrogen (LN2); whereas in the solid surface group, vitrified COCs were first loaded by cryotops and then cooled before plunging into LN2. Post-warming survivability and ultrastructural changes of healthy COCs in the cryotop group especially in comparison with the conventional group revealed better viability rate and good preservation of the ooplasm organization. However in all vitrification groups except the cryotop group, mitochondria were clumped. Solely in the conventional straw group, the mitochondria showed different densities and were extremely distended. Moreover in the latter group, plenty of large irregular connected vesicles in the ooplasm were observed and in some parts their membrane ruptured. Also, in the conventional and solid surface vitrification groups, cumulus cells projections became retracted from the zona pellucida in some parts. In conclusion, the cryotop vitrification method as compared with other methods seems to have a good post-warming survivability and shows less deleterious effects on the ultrastructure of healthy vitrified-warmed sheep COCs.

  4. Effect of microwave-assisted sintering on dielectric properties of CaCu3Ti4O12 ceramic

    NASA Astrophysics Data System (ADS)

    Rani, Suman; Ahlawat, Neetu; Punia, R.; Kundu, R. S.; Ahlawat, N.

    2016-05-01

    In this present work, CaCu3Ti4O12 (CCTO) was synthesized by conventional solid-state reaction technique. The synthesis process was carried out in two phases; by conventional process (calcination and sintering at 1080°C for 10 hours) and phase II involves the micro assisted pre sintering of conventionally calcined CCTO for very short soaking time of 30 min at 1080°C in a microwave furnace followed by sintering at 1080°C for 10 hours in conventional furnace. X-ray diffraction (XRD) patterns confirmed the formation of single phase ceramic. Dielectric properties were studied over the frequency range from 50Hz -5MHz at temperatures (273K-343K). It was observed that pre- microwave sintering enhance the dielectric constant values from 10900 to 11893 and respectively reduces the dielectric loss values from 0.49 to 0.34 at room temperature(1 KHz). CCTO ceramics which are found desirable for many technological applications. The effect is more pronounced at low frequencies of applied electric field.

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berger, Cornelius M.; Mahmoud, Abdelfattah; Hermann, Raphaël P.

    Rechargeable oxide batteries (ROB) comprise a regenerative solid oxide cell (rSOC) and a storage medium for oxygen ions. A sealed ROB avoids pumping loss, heat loss, and gas purity expenses in comparison with conventional rSOC. However, the iron oxide base storage medium degrades during charging–discharging cycles. In comparison, CaFe 3O 5 has improved cyclability and a high reversible oxygen storage capacity of 22.3 mol%. In this paper, we analyzed the redox mechanism of this compound. After a solid-state synthesis of CaFe 3O 5, we verified the phase composition and studied the redox reaction by means of X-ray diffraction, Mössbauer spectrometry,more » and scanning electron microscopy. Finally, results show a great potential to operate the battery with this storage material during multiple charging–discharging cycles.« less

  6. Mercury emission to the atmosphere from municipal solid waste landfills: A brief review

    NASA Astrophysics Data System (ADS)

    Tao, Zhengkai; Dai, Shijin; Chai, Xiaoli

    2017-12-01

    Municipal solid waste (MSW) landfill is regarded as an important emission source of atmospheric mercury (Hg), which is associated with potential health and environmental risks, as outlined by the Minamata Convention on Hg. This review presents the current state of knowledge with regards to landfill Hg sources, Hg levels in MSW and cover soils, Hg emission to the atmosphere, available Hg biogeochemical transformations, research methods for Hg emission, and important areas for future research. In addition, strategies for controlling landfill Hg emissions are considered, including reducing the Hg load in landfill and in situ controls. These approaches mainly focus on Hg source reduction, Hg recycling programs, public education, and in situ technology such as timely soil cover, vegetation, and end-of-pipe technology for controlling Hg emission from landfill gas.

  7. Evaluation of Stability and Biological Activity of Solid Nanodispersion of Lambda-Cyhalothrin.

    PubMed

    Cui, Bo; Feng, Lei; Pan, Zhenzhong; Yu, Manli; Zeng, Zhanghua; Sun, Changjiao; Zhao, Xiang; Wang, Yan; Cui, Haixin

    2015-01-01

    Pesticides are essential agrochemicals used to protect plants from diseases, pests and weeds. However, the formulation defects of conventional pesticides cause food toxicity and ecological environmental problems. In this study, a novel, efficient and environmentally friendly formulation of lambda-cyhalothrin, a solid nanodispersion, was successfully developed based on melt-emulsification and high-speed shearing methods. The solid nanodispersion presented excellent advantages over conventional pesticide formulations in such formulation functions as dispersibility, stability and bioavailability. The formulation is free of organic solvents, and the use of surfactant is reduced. Therefore, the application of the solid nanodispersion in crop production will improve efficacy and reduce the occurrence of both pesticide residues in food and environmental pollution from pesticides.

  8. Evaluation of Stability and Biological Activity of Solid Nanodispersion of Lambda-Cyhalothrin

    PubMed Central

    Cui, Bo; Feng, Lei; Pan, Zhenzhong; Yu, Manli; Zeng, Zhanghua; Sun, Changjiao; Zhao, Xiang; Wang, Yan; Cui, Haixin

    2015-01-01

    Pesticides are essential agrochemicals used to protect plants from diseases, pests and weeds. However, the formulation defects of conventional pesticides cause food toxicity and ecological environmental problems. In this study, a novel, efficient and environmentally friendly formulation of lambda-cyhalothrin, a solid nanodispersion, was successfully developed based on melt-emulsification and high-speed shearing methods. The solid nanodispersion presented excellent advantages over conventional pesticide formulations in such formulation functions as dispersibility, stability and bioavailability. The formulation is free of organic solvents, and the use of surfactant is reduced. Therefore, the application of the solid nanodispersion in crop production will improve efficacy and reduce the occurrence of both pesticide residues in food and environmental pollution from pesticides. PMID:26281043

  9. Grand Challenges and Future Opportunities for Metal–Organic Frameworks

    PubMed Central

    2017-01-01

    Metal–organic frameworks (MOFs) allow compositional and structural diversity beyond conventional solid-state materials. Continued interest in the field is justified by potential applications of exceptional breadth, ranging from gas storage and separation, which takes advantage of the inherent pores and their volume, to electronic applications, which requires precise control of electronic structure. In this Outlook we present some of the pertinent challenges that MOFs face in their conventional implementations, as well as opportunities in less traditional areas. Here the aim is to discuss select design concepts and future research goals that emphasize nuances relevant to this class of materials as a whole. Particular emphasis is placed on synthetic aspects, as they influence the potential for MOFs in gas separation, electrical conductivity, and catalytic applications. PMID:28691066

  10. Integrated structure vacuum tube

    NASA Technical Reports Server (NTRS)

    Dimeff, J.; Kerwin, W. J. (Inventor)

    1976-01-01

    High efficiency, multi-dimensional thin film vacuum tubes suitable for use in high temperature, high radiation environments are described. The tubes are fabricated by placing thin film electrode members in selected arrays on facing interior wall surfaces of an alumina substrate envelope. Cathode members are formed using thin films of triple carbonate. The photoresist used in photolithography aids in activation of the cathodes by carbonizing and reacting with the reduced carbonates when heated in vacuum during forming. The finely powdered triple carbonate is mixed with the photoresist used to delineate the cathode locations in the conventional solid state photolithographic manner. Anode and grid members are formed using thin films of refractory metal. Electron flow in the tubes is between grid elements from cathode to anode as in a conventional three-dimensional tube.

  11. Use of photovoltaic detector for photocatalytic activity estimation

    NASA Astrophysics Data System (ADS)

    Das, Susanta Kumar; Satapathy, Pravakar; Rao, P. Sai Shruti; Sabar, Bilu; Panda, Rudrashish; Khatua, Lizina

    2018-05-01

    Photocatalysis is a very important process and have numerous applications. Generally, to estimate the photocatalytic activity of newly grown material, its reaction rate constant w.r.t to some standard commercial TiO2 nanoparticles like Degussa P25 is evaluated. Here a photovoltaic detector in conjunction with laser is used to determine this rate constant. This method is tested using Zinc Orthotitanate (Zn2TiO4) nanoparticles prepared by solid state reaction and it is found that its reaction rate constant is six times higher than that of P25. The value is found to be close to the value found by a conventional system. Our proposed system is much more cost-effective than the conventional one and has the potential to do real time monitoring of the photocatalytic activity.

  12. Grand Challenges and Future Opportunities for Metal–Organic Frameworks

    DOE PAGES

    Hendon, Christopher H.; Rieth, Adam J.; Korzyński, Maciej D.; ...

    2017-06-06

    Metal–organic frameworks (MOFs) allow compositional and structural diversity beyond conventional solid-state materials. Continued interest in the field is justified by potential applications of exceptional breadth, ranging from gas storage and separation, which takes advantage of the inherent pores and their volume, to electronic applications, which requires precise control of electronic structure. In this Outlook we present some of the pertinent challenges that MOFs face in their conventional implementations, as well as opportunities in less traditional areas. Here the aim is to discuss select design concepts and future research goals that emphasize nuances relevant to this class of materials as amore » whole. Particular emphasis is placed on synthetic aspects, as they influence the potential for MOFs in gas separation, electrical conductivity, and catalytic applications.« less

  13. Large angle solid state position sensitive x-ray detector system

    DOEpatents

    Kurtz, D.S.; Ruud, C.O.

    1998-03-03

    A method and apparatus for x-ray measurement of certain properties of a solid material are disclosed. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided. 7 figs.

  14. Large angle solid state position sensitive x-ray detector system

    DOEpatents

    Kurtz, D.S.; Ruud, C.O.

    1998-07-21

    A method and apparatus are disclosed for x-ray measurement of certain properties of a solid material. In distinction to known methods and apparatus, this invention employs a specific fiber-optic bundle configuration, termed a reorganizer, itself known for other uses, for coherently transmitting visible light originating from the scintillation of diffracted x-radiation from the solid material gathered along a substantially one dimensional linear arc, to a two-dimensional photo-sensor array. The two-dimensional photodetector array, with its many closely packed light sensitive pixels, is employed to process the information contained in the diffracted radiation and present the information in the form of a conventional x-ray diffraction spectrum. By this arrangement, the angular range of the combined detector faces may be increased without loss of angular resolution. Further, the prohibitively expensive coupling together of a large number of individual linear diode photodetectors, which would be required to process signals generated by the diffracted radiation, is avoided. 7 figs.

  15. Surface chemistry of carbon dioxide revisited

    NASA Astrophysics Data System (ADS)

    Taifan, William; Boily, Jean-François; Baltrusaitis, Jonas

    2016-12-01

    This review discusses modern developments in CO2 surface chemistry by focusing on the work published since the original review by H.J. Freund and M.W. Roberts two decades ago (Surface Science Reports 25 (1996) 225-273). It includes relevant fundamentals pertaining to the topics covered in that earlier review, such as conventional metal and metal oxide surfaces and CO2 interactions thereon. While UHV spectroscopy has routinely been applied for CO2 gas-solid interface analysis, the present work goes further by describing surface-CO2 interactions under elevated CO2 pressure on non-oxide surfaces, such as zeolites, sulfides, carbides and nitrides. Furthermore, it describes additional salient in situ techniques relevant to the resolution of the interfacial chemistry of CO2, notably infrared spectroscopy and state-of-the-art theoretical methods, currently used in the resolution of solid and soluble carbonate species in liquid-water vapor, liquid-solid and liquid-liquid interfaces. These techniques are directly relevant to fundamental, natural and technological settings, such as heterogeneous and environmental catalysis and CO2 sequestration.

  16. Solid dispersion of efavirenz in PVP K-30 by conventional solvent and kneading methods.

    PubMed

    Alves, Lariza Darlene Santos; de La Roca Soares, Mônica Felts; de Albuquerque, Camila Tavares; da Silva, Elica Rodrigues; Vieira, Alexandre Couto Carneiro; Fontes, Danilo Augusto Ferreira; Figueirêdo, Camila Bezerra Melo; Soares Sobrinho, José Lamartine; Rolim Neto, Pedro José

    2014-04-15

    Efavirenz (EFV) used as a part of the treatment of first choice in antiretroviral therapy for AIDS has low aqueous solubility and presents problems of absorption. We thus initially present a phase solubility diagram with carriers of different classes. With a view to obtaining a solid dispersion (SD) with suitable consistency to that of a solid formulation, we chose to use PVP K-30, since polymers present some of the best results. The kneading (KN) and solvent evaporation (EV) methods were thus used at different rates. These were characterized by the way of DSC, FT-IR, SEM, DR-X and dissolution. SD EV proved unsatisfactory, resulting in a decreased dissolution rate, despite the amorphous state of the samples, while the SD KN 4:1 (EFV:polymer) and physical mixtures (PM) had a higher rate of dissolution. SD KN and PM 4:1 were also evaluated for stability after storage, with benefits being observed in relation to EFV. Copyright © 2014. Published by Elsevier Ltd.

  17. Defects in electro-optically active polymer solids

    NASA Technical Reports Server (NTRS)

    Martin, David C.

    1993-01-01

    There is considerable current interest in the application of organic and polymeric materials for electronic and photonic devices. The rapid, non-linear optical (NLO) response of these materials makes them attractive candidates for waveguides, interferometers, and frequency doublers. In order to realize the full potential of these systems, it is necessary to develop processing schemes which can fabricate these molecules into ordered arrangements. There is enormous potential for introducing well-defined, local variations in microstructure to control the photonic properties of organic materials by rational 'defect engineering.' This effort may eventually become as technologically important as the manipulation of the electronic structure of solid-state silicon based devices is at present. The success of this endeavor will require complimentary efforts in the synthesis, processing, and characterization of new materials. Detailed information about local microstructure will be necessary to understand the influence of symmetry breaking of the solid phases near point, line, and planar defects. In metallic and inorganic polycrystalline materials, defects play an important role in modifying macroscopic properties. To understand the influence of particular defects on the properties of materials, it has proven useful to isolate the defect by creating bicrystals between two-component single crystals. In this way the geometry of a grain boundary defect and its effect on macroscopic properties can be determined unambiguously. In crystalline polymers it would be valuable to establish a similar depth of understanding about the relationship between defect structure and macroscopic properties. Conventionally processed crystalline polymers have small crystallites (10-20 nm), which implies a large defect density in the solid state. Although this means that defects may play an important or even dominant role in crystalline or liquid crystalline polymer systems, it also makes it difficult to isolate the effect of a particular boundary on a macroscopically observed property. However, the development of solid-state and thin-film polymerization mechanisms have facilitated the synthesis of highly organized and ordered polymers. These systems provide a unique opportunity to isolate and investigate in detail the structure of covalently bonded solids near defects and the effect of these defects on the properties of the material. The study of defects in solid polymers has been the subject of a recent review (Martin, 1993).

  18. Fabrication of single domain GdBCO bulk superconductors by a new modified TSIG technique

    NASA Astrophysics Data System (ADS)

    Yang, W. M.; Zhi, X.; Chen, S. L.; Wang, M.; Li, J. W.; Ma, J.; Chao, X. X.

    2014-01-01

    Single domain GdBCO bulk superconductors have been fabricated with new and traditional solid phases by a top seeded infiltration and growth (TSIG) process technique. In the conventional TSIG process, three types of powders, such as Gd2BaCuO5, GdBa2Cu3O7-x and Ba3Cu5O8, must be prepared, but in our new modified TSIG technique, only BaCuO2 powders are required during the fabrication of the single domain GdBCO bulk superconductors. The solid phase used in the conventional process is Gd2BaCuO5 instead of the solid phase (Gd2O3 + BaCuO2) utilized in the new process. The liquid phase used in the conventional process is a mixture of (GdBa2Cu3O7-x + Ba3Cu5O8), and the liquid phase in the new process is a mixture of (Gd2O3 + 10BaCuO2 + 6CuO). Single domain GdBCO bulk superconductors have been fabricated with the new solid and liquid phases. The levitation force of the GdBCO bulk samples fabricated by the new solid phase is 28 N, which is slightly higher than that of the samples fabricated using the conventional solid phases (26 N). The microstructure and the levitation force of the samples indicate that this new method can greatly simplify the fabrication process, introduce nanometer-sized flux centers, improve the levitation force and working efficiency, and greatly reduce the cost of fabrication of single domain GdBCO bulk superconductors by the TSIG process.

  19. Improved physicochemical characteristics of felodipine solid dispersion particles by supercritical anti-solvent precipitation process.

    PubMed

    Won, Dong-Han; Kim, Min-Soo; Lee, Sibeum; Park, Jeong-Sook; Hwang, Sung-Joo

    2005-09-14

    Solid dispersions of felodipine were formulated with HPMC and surfactants by the conventional solvent evaporation (CSE) and supercritical anti-solvent precipitation (SAS) methods. The solid dispersion particles were characterized by particle size, zeta potential, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), solubility and dissolution studies. The effects of the drug/polymer ratio and surfactants on the solubility of felodipine were also studied. The mean particle size of the solid dispersions was 200-250 nm; these had a relatively regular spherical shape with a narrow size distribution. The particle size of the solid dispersions from the CSE method increased at 1 h after dispersed in distilled water. However, the particle sizes of solid dispersions from the SAS process were maintained for 6 h due to the increased solubility of felodipine. The physical state of felodipine changed from crystalline to amorphous during the CSE and SAS processes, confirmed by DSC/XRD data. The equilibrium solubility of the felodipine solid dispersion prepared by the SAS process was 1.5-20 microg/ml, while the maximum solubility was 35-110 microg/ml. Moreover, the solubility of felodipine increased with decreasing drug/polymer ratio or increasing HCO-60 content. The solid dispersions from the SAS process showed a high dissolution rate of over 90% within 2 h. The SAS process system may be used to enhance solubility or to produce oral dosage forms with high dissolution rate.

  20. Demonstration-scale evaluation of a novel high-solids anaerobic digestion process for converting organic wastes to fuel gas and compost.

    PubMed

    Rivard, C J; Duff, B W; Dickow, J H; Wiles, C C; Nagle, N J; Gaddy, J L; Clausen, E C

    1998-01-01

    Early evaluations of the bioconversion potential for combined wastes such as tuna sludge and sorted municipal solid waste (MSW) were conducted at laboratory scale and compared conventional low-solids, stirred-tank anaerobic systems with the novel, high-solids anaerobic digester (HSAD) design. Enhanced feedstock conversion rates and yields were determined for the HSAD system. In addition, the HSAD system demonstrated superior resiliency to process failure. Utilizing relatively dry feedstocks, the HSAD system is approximately one-tenth the size of conventional low-solids systems. In addition, the HSAD system is capable of organic loading rates (OLRs) on the order of 20-25 g volatile solids per liter digester volume per d (gVS/L/d), roughly 4-5 times those of conventional systems. Current efforts involve developing a demonstration-scale (pilot-scale) HSAD system. A two-ton/d plant has been constructed in Stanton, CA and is currently in the commissioning/startup phase. The purposes of the project are to verify laboratory- and intermediate-scale process performance; test the performance of large-scale prototype mechanical systems; demonstrate the long-term reliability of the process; and generate the process and economic data required for the design, financing, and construction of full-scale commercial systems. This study presents conformational fermentation data obtained at intermediate-scale and a snapshot of the pilot-scale project.

  1. Characterization and evaluation of avermectin solid nanodispersion prepared by microprecipitation and lyophilisation techniques

    PubMed Central

    Wang, Chunxin; Zhao, Xiang; Yao, Junwei; Zeng, Zhanghua; Wang, Yan; Sun, Changjiao; Liu, Guoqiang; Cui, Haixin

    2018-01-01

    Poorly water-soluble and photosensitive pesticide compounds are difficult to formulate as solvent-free nanoformulations with high efficacy. A avermectin solid nanodispersion with a mean particle size of 188 nm was developed by microprecipitation and lyophilisation techniques. The suspensibility and wetting time of the solid nanodispersion in water were 99.8% and 13 s, respectively, superior to those of conventional water dispersible granules and wettable powders. The anti-photolysis performance of the nanoformulation was twice that of the technical material, and the biological activity against diamondback moths was more than 1.5 times that of the conventional solid formulations while taking LC 50 as the evaluation index. Moreover, the formulation composition substantially decreased the surfactant content and avoided organic solvents. Microprecipitation combined with lyophilisation is an easy and promising method to construct solid nanoformulations for pesticides with poor water solubility and environmental sensitivity. The application of the highly effective solid nanodispersion in crop production will have a great potential in reducing chemical residues and environmental pollution. PMID:29360866

  2. Physicochemical characterization of solid dispersions of carbamazepine formulated by supercritical carbon dioxide and conventional solvent evaporation method.

    PubMed

    Sethia, Sundeep; Squillante, Emilio

    2002-09-01

    Solid dispersions of carbamazepine (CBZ) were formulated by supercritical fluid processing (SCP) and conventional solvent evaporation in polyethylene glycol (PEG) 8000 with either Gelucire 44/14 or vitamin E TPGS NF (d-alpha-tocopheryl PEG 1000 succinate). Formulations were evaluated by dissolution, scanning electron microscopy, powder X-ray diffraction, and differential scanning calorimetry, and excipient cytotoxicity in Caco-2 cells by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt] assay. CBZ release was enhanced from supercritical fluid-treated CBZ and the CBZ/PEG 8000 (1:5), CBZ/PEG 8000/TPGS or Gelucire 44/14 (1:4:1) solid dispersions. The radically altered morphologies of SCP samples seen by scanning electron microscopy suggested polymorphic change that was confirmed by the X-ray diffraction and differential scanning calorimetry. Disappearance of the characteristic CBZ melting peak indicated that CBZ was dissolved inside the carrier system. Polymorphic change of CBZ during SCP led to faster dissolution. Therefore, SCP provides advantages over solid dispersions prepared by conventional processes. Copyright 2002 Wiley-Liss Inc.

  3. Potential impact of ZT = 4 thermoelectric materials on solar thermal energy conversion technologies.

    PubMed

    Xie, Ming; Gruen, Dieter M

    2010-11-18

    State-of-the-art methodologies for the conversion of solar thermal power to electricity are based on conventional electromagnetic induction techniques. If appropriate ZT = 4 thermoelectric materials were available, it is likely that conversion efficiencies of 30-40% could be achieved. The availability of all solid state electricity generation would be a long awaited development in part because of the elimination of moving parts. This paper presents a preliminary examination of the potential performance of ZT = 4 power generators in comparison with Stirling engines taking into account specific mass, volume and cost as well as system reliability. High-performance thermoelectrics appear to have distinct advantages over magnetic induction technologies.

  4. Remote quantum entanglement between two micromechanical oscillators.

    PubMed

    Riedinger, Ralf; Wallucks, Andreas; Marinković, Igor; Löschnauer, Clemens; Aspelmeyer, Markus; Hong, Sungkun; Gröblacher, Simon

    2018-04-01

    Entanglement, an essential feature of quantum theory that allows for inseparable quantum correlations to be shared between distant parties, is a crucial resource for quantum networks 1 . Of particular importance is the ability to distribute entanglement between remote objects that can also serve as quantum memories. This has been previously realized using systems such as warm 2,3 and cold atomic vapours 4,5 , individual atoms 6 and ions 7,8 , and defects in solid-state systems 9-11 . Practical communication applications require a combination of several advantageous features, such as a particular operating wavelength, high bandwidth and long memory lifetimes. Here we introduce a purely micromachined solid-state platform in the form of chip-based optomechanical resonators made of nanostructured silicon beams. We create and demonstrate entanglement between two micromechanical oscillators across two chips that are separated by 20 centimetres . The entangled quantum state is distributed by an optical field at a designed wavelength near 1,550 nanometres. Therefore, our system can be directly incorporated in a realistic fibre-optic quantum network operating in the conventional optical telecommunication band. Our results are an important step towards the development of large-area quantum networks based on silicon photonics.

  5. Solid Waste Management with Emphasis on Environmental Aspect

    NASA Astrophysics Data System (ADS)

    Sinha, Navin Kr.; Choudhary, Binod Kumar; Shree, Shalini

    2011-12-01

    In this paper focus on Solid waste management. Its comprises of purposeful and systematic control of generation, storage, collection, transport, separations, processing, recycling, recovery and disposal of solid waste. Awareness of Four R's management & EMS support also for management Solid waste. Basel convention on the Control of transboundary movements of hazardous wastes and their Disposal usually known simply as the Basel Convention, is an international treaty that was designed to reduce the movements of hazardous waste between nations, and specifically to prevent transfer of hazardous waste from developed to less developed countries (LDCs). it came into force 5 May 1992. According to this "Substances or objects which are disposed of or are intended to be disposed of or are required to be disposed of by the provisions of national law"(UNEP).

  6. Application of the Flory-Huggins theory to the solubility of solids in glyceryl trioleate

    USGS Publications Warehouse

    Chiou, Cary T.; Manes, Milton

    1986-01-01

    The conventional thermodynamic deviation for ideal solid–liquid solubilities is modified by substituting the Flory–Huggins model for Raoult's law. A comparison of published data for eleven solides in glyceryl trioleate with the predictions of the conventional and modified equations shows that the significantly higher athermal solubilities from the modified equation are in much better agreement with the experimental data. This suggests that discrepancies between the data and the predictions of the conventional model for ideal systems result from the inappropriate use of Raoult's law for systems with significant solute–solvent size disparity rather than from specific interactions.

  7. Time-resolved methods in biophysics. 7. Photon counting vs. analog time-resolved singlet oxygen phosphorescence detection.

    PubMed

    Jiménez-Banzo, Ana; Ragàs, Xavier; Kapusta, Peter; Nonell, Santi

    2008-09-01

    Two recent advances in optoelectronics, namely novel near-IR sensitive photomultipliers and inexpensive yet powerful diode-pumped solid-state lasers working at kHz repetition rate, enable the time-resolved detection of singlet oxygen (O2(a1Deltag)) phosphorescence in photon counting mode, thereby boosting the time-resolution, sensitivity, and dynamic range of this well-established detection technique. Principles underlying this novel approach and selected examples of applications are provided in this perspective, which illustrate the advantages over the conventional analog detection mode.

  8. Aircraft photovoltaic power-generating system

    NASA Astrophysics Data System (ADS)

    Doellner, Oscar Leonard

    Photovoltaic cells, appropriately cooled and operating in the combustion-created high radiant-intensity environment of gas-turbine and jet engines, may replace the conventional (gearbox-driven) electrical power generators aboard jet aircraft. This study projects significant improvements not only in aircraft electrical power-generating-system performance, but also in overall aircraft performance. Jet-engine design modifications incorporating this concept not only save weight (and thus fuel), but are - in themselves - favorable to jet-engine performance. The dissertation concentrates on operational, constructional, structural, thermal, optical, radiometrical, thin-film, and solid-state theoretical aspects of the overall project.

  9. Broadband electron spin resonance at low frequency without resonant cavity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jang, Z.; Suh, B.; Corti, M.

    2008-04-09

    We have developed a nonconventional broadband electron spin resonance (ESR) spectrometer operating continuously in the frequency range from 0.5 to 9 GHz. Dual antenna structure and the microwave absorbing environment differentiate the setup from the conventional one and enable broadband operation with any combination of frequency or magnetic field modulation and frequency or magnetic field sweeping. Its performance has been tested with the measurements on a 1,1-diphenyl-2-picrylhydrazyl (DPPH) sample and with the measurements on the single molecular magnet, V6, in solid state at low temperature.

  10. Fabrication and characteristics of experimental radiographic amplifier screens. [image transducers with improved image contrast and resolution

    NASA Technical Reports Server (NTRS)

    Szepesi, Z.

    1978-01-01

    The fabrication process and transfer characteristics for solid state radiographic image transducers (radiographic amplifier screens) are described. These screens are for use in realtime nondestructive evaluation procedures that require large format radiographic images with contrast and resolution capabilities unavailable with conventional fluoroscopic screens. The screens are suitable for in-motion, on-line radiographic inspection by means of closed circuit television. Experimental effort was made to improve image quality and response to low energy (5 kV and up) X-rays.

  11. Challenges and opportunities of the bio-pesticides production by solid-state fermentation: filamentous fungi as a model.

    PubMed

    De la Cruz Quiroz, Reynaldo; Roussos, Sevastianos; Hernández, Daniel; Rodríguez, Raúl; Castillo, Francisco; Aguilar, Cristóbal N

    2015-01-01

    In recent years, production and use of bio-pesticides have increasing and replacing some synthetic chemical pesticides applied to food commodities. In this review, biological control is focused as an alternative, to some synthetic chemical treatments that cause environmental, human health, and food quality risks. In addition, several phytopathogenic microorganisms have developed resistance to some of these synthetic chemicals and become more difficult to control. Worldwide, the bio-pesticides market is growing annually at a rate of 44% in North America, 20% in Europe and Oceania, 10% in Latin and South American countries and 6% in Asia. Use of agro-industrial wastes and solid-state fermentation (SSF) technology offers an alternative to bio-pesticide production with advantages versus conventional submerged fermentations, as reduced cost and energy consumption, low production of residual water and high stability products. In this review, recent data about state of art regarding bio-pesticides production under SSF on agroindustrial wastes will be discussed. SSF can be defined as a microbial process that generally occurs on solid material in the absence of free water. This material has the ability to absorb water with or without soluble nutrients, since the substrate must have water to support the microorganism's growth and metabolism. Changes in water content are analyzed in order to select the conditions for a future process, where water stress can be combined with the best spore production conditions, obtaining in this way an inexpensive biotechnological option for modern agriculture in developing countries.

  12. A Modified Alderman-Grant Coil makes possible an efficient cross-coil probe for high field solid-state NMR of lossy biological samples

    NASA Astrophysics Data System (ADS)

    Grant, Christopher V.; Yang, Yuan; Glibowicka, Mira; Wu, Chin H.; Park, Sang Ho; Deber, Charles M.; Opella, Stanley J.

    2009-11-01

    The design, construction, and performance of a cross-coil double-resonance probe for solid-state NMR experiments on lossy biological samples at high magnetic fields are described. The outer coil is a Modified Alderman-Grant Coil (MAGC) tuned to the 1H frequency. The inner coil consists of a multi-turn solenoid coil that produces a B 1 field orthogonal to that of the outer coil. This results in a compact nested cross-coil pair with the inner solenoid coil tuned to the low frequency detection channel. This design has several advantages over multiple-tuned solenoid coil probes, since RF heating from the 1H channel is substantially reduced, it can be tuned for samples with a wide range of dielectric constants, and the simplified circuit design and high inductance inner coil provides excellent sensitivity. The utility of this probe is demonstrated on two electrically lossy samples of membrane proteins in phospholipid bilayers (bicelles) that are particularly difficult for conventional NMR probes. The 72-residue polypeptide embedding the transmembrane helices 3 and 4 of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) (residues 194-241) requires a high salt concentration in order to be successfully reconstituted in phospholipid bicelles. A second application is to paramagnetic relaxation enhancement applied to the membrane-bound form of Pf1 coat protein in phospholipid bicelles where the resistance to sample heating enables high duty cycle solid-state NMR experiments to be performed.

  13. Digital imaging with solid state x-ray image intensifiers

    NASA Astrophysics Data System (ADS)

    Damento, Michael A.; Radspinner, Rachel; Roehrig, Hans

    1999-10-01

    X-ray cameras in which a CCD is lens coupled to a large phosphor screen are known to suffer from a loss of x-ray signal due to poor light collection from conventional phosphors, making them unsuitable for most medical imaging applications. By replacing the standard phosphor with a solid-state image intensifier, it may be possible to improve the signal-to-noise ratio of the images produced with these cameras. The solid-state x-ray image intensifier is a multi- layer device in which a photoconductor layer controls the light output from an electroluminescent phosphor layer. While prototype devices have been used for direct viewing and video imaging, they are only now being evaluated in a digital imaging system. In the present work, the preparation and evaluation of intensifiers with a 65 mm square format are described. The intensifiers are prepared by screen- printing or doctor blading the following layers onto an ITO coated glass substrate: ZnS phosphor, opaque layer, CdS photoconductor, and carbon conductor. The total thickness of the layers is approximately 350 micrometers , 350 VAC at 400 Hz is applied to the device for operation. For a given x-ray dose, the intensifiers produce up to three times the intensity (after background subtracting) of Lanex Fast Front screens. X-ray images produced with the present intensifiers are somewhat noisy and their resolution is about half that of Lanex screens. Modifications are suggested which could improve the resolution and noise of the intensifiers.

  14. Bottom-Up and Top-Down Solid-State NMR Approaches for Bacterial Biofilm Matrix Composition

    PubMed Central

    Cegelski, Lynette

    2015-01-01

    The genomics and proteomics revolutions have been enormously successful in providing crucial “parts lists” for biological systems. Yet, formidable challenges exist in generating complete descriptions of how the parts function and assemble into macromolecular complexes and whole-cell assemblies. Bacterial biofilms are complex multicellular bacterial communities protected by a slime-like extracellular matrix that confers protection to environmental stress and enhances resistance to antibiotics and host defenses. As a non-crystalline, insoluble, heterogeneous assembly, the biofilm extracellular matrix poses a challenge to compositional analysis by conventional methods. In this Perspective, bottom-up and top-down solid-state NMR approaches are described for defining chemical composition in complex macrosystems. The “sum-of-theparts” bottom-up approach was introduced to examine the amyloid-integrated biofilms formed by E. coli and permitted the first determination of the composition of the intact extracellular matrix from a bacterial biofilm. An alternative top-down approach was developed to define composition in V. cholerae biofilms and relied on an extensive panel of NMR measurements to tease out specific carbon pools from a single sample of the intact extracellular matrix. These two approaches are widely applicable to other heterogeneous assemblies. For bacterial biofilms, quantitative parameters of matrix composition are needed to understand how biofilms are assembled, to improve the development of biofilm inhibitors, and to dissect inhibitor modes of action. Solid-state NMR approaches will also be invaluable in obtaining parameters of matrix architecture. PMID:25797008

  15. Bottom-up and top-down solid-state NMR approaches for bacterial biofilm matrix composition.

    PubMed

    Cegelski, Lynette

    2015-04-01

    The genomics and proteomics revolutions have been enormously successful in providing crucial "parts lists" for biological systems. Yet, formidable challenges exist in generating complete descriptions of how the parts function and assemble into macromolecular complexes and whole-cell assemblies. Bacterial biofilms are complex multicellular bacterial communities protected by a slime-like extracellular matrix that confers protection to environmental stress and enhances resistance to antibiotics and host defenses. As a non-crystalline, insoluble, heterogeneous assembly, the biofilm extracellular matrix poses a challenge to compositional analysis by conventional methods. In this perspective, bottom-up and top-down solid-state NMR approaches are described for defining chemical composition in complex macrosystems. The "sum-of-the-parts" bottom-up approach was introduced to examine the amyloid-integrated biofilms formed by Escherichia coli and permitted the first determination of the composition of the intact extracellular matrix from a bacterial biofilm. An alternative top-down approach was developed to define composition in Vibrio cholerae biofilms and relied on an extensive panel of NMR measurements to tease out specific carbon pools from a single sample of the intact extracellular matrix. These two approaches are widely applicable to other heterogeneous assemblies. For bacterial biofilms, quantitative parameters of matrix composition are needed to understand how biofilms are assembled, to improve the development of biofilm inhibitors, and to dissect inhibitor modes of action. Solid-state NMR approaches will also be invaluable in obtaining parameters of matrix architecture. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Bottom-up and top-down solid-state NMR approaches for bacterial biofilm matrix composition

    NASA Astrophysics Data System (ADS)

    Cegelski, Lynette

    2015-04-01

    The genomics and proteomics revolutions have been enormously successful in providing crucial "parts lists" for biological systems. Yet, formidable challenges exist in generating complete descriptions of how the parts function and assemble into macromolecular complexes and whole-cell assemblies. Bacterial biofilms are complex multicellular bacterial communities protected by a slime-like extracellular matrix that confers protection to environmental stress and enhances resistance to antibiotics and host defenses. As a non-crystalline, insoluble, heterogeneous assembly, the biofilm extracellular matrix poses a challenge to compositional analysis by conventional methods. In this perspective, bottom-up and top-down solid-state NMR approaches are described for defining chemical composition in complex macrosystems. The "sum-of-the-parts" bottom-up approach was introduced to examine the amyloid-integrated biofilms formed by Escherichia coli and permitted the first determination of the composition of the intact extracellular matrix from a bacterial biofilm. An alternative top-down approach was developed to define composition in Vibrio cholerae biofilms and relied on an extensive panel of NMR measurements to tease out specific carbon pools from a single sample of the intact extracellular matrix. These two approaches are widely applicable to other heterogeneous assemblies. For bacterial biofilms, quantitative parameters of matrix composition are needed to understand how biofilms are assembled, to improve the development of biofilm inhibitors, and to dissect inhibitor modes of action. Solid-state NMR approaches will also be invaluable in obtaining parameters of matrix architecture.

  17. Solid state recycling of aluminium alloys via a porthole die hot extrusion process: Scaling up to production

    NASA Astrophysics Data System (ADS)

    Paraskevas, Dimos; Kellens, Karel; Deng, Yelin; Dewulf, Wim; Kampen, Carlos; Duflou, Joost R.

    2017-10-01

    Whereas industrial symbiosis has led to increased energy and resource efficiency in process industries, this concept has not yet been applied in discrete product manufacturing. Metal scrap is first conventionally recycled, for which substantial energy and resource efficiency losses have been reported. Recent research has however proven the feasibility of `meltless' recycling of light metal scrap, yielding a first glimpse of potential industrial symbiosis. Various solid state recycling techniques (such as recycling via hot extrusion or Spark Plasma Sintering) have been proposed for scrap consolidation directly into bulk products or semis by physical disruption and dispersion of the oxide surface film by imposing significant plastic and shear strain. Solid State Recycling (SSR) methods can omit substantial material losses as they bypass the metallurgical recycling step. In this context the case of direct production of bulk aluminium profiles via hot extrusion at industrial scale is demonstrated within this paper. The extrusion tests were performed directly into the production line, highlighting the scaling up potentials and the industrial relevance of this research. A significant amount of machining chips were collected, chemically cleaned and cold compacted into chip based billets with ˜80% relative density. Afterwards the scrap consolidation was achieved by imposing significant plastic and shear deformation into the material during hot extrusion through a modified 2-porthole extrusion die-set. The production process sequence along with microstructural investigations and mechanical properties comparison of the cast based profile used as reference versus the chip based profile are presented.

  18. ARPA solid state laser and nonlinear materials program

    NASA Astrophysics Data System (ADS)

    Moulton, Peter F.

    1994-06-01

    The Research Division of Schwartz Electro-Optics, as part of the ARPA Solid State Laser and Nonlinear Materials Program, conducted a three-year study 'Erbium-Laser-Based Infrared Sources.' The aim of the study was to improve the understanding of semiconductor-laser-pumped, infrared (IR) solid state lasers based on the trivalent rare-earth ion erbium (Er) doped into a variety of host crystals. The initial program plan emphasized operation of erbium-doped materials on the 2.8-3.0 micrometers laser transition. Pulsed, Q-switched sources using that transition, when employed as a pump source for parametric oscillators, can provide tunable mid-IR energy. The dynamics of erbium lasers are more complex than conventional neodymium (Nd)-doped lasers and we intended to use pump-probe techniques to measure the level and temporal behavior of gain in various materials. To do so we constructed a number of different cw Er-doped lasers as probe sources and employed the Cr:LiSAF(LiSrAlF6) laser as a pulsed pump source that would simulate pulsed diode arrays. We identified the 970-nm wavelength pump band of Er as the most efficient and were able to make use of recently developed cw and pulsed InGaAs strained-quantum-well diode lasers in the effort. At the conclusion of the program we demonstrated the first pulsed diode bar pumping of the most promising materials for pulsed operation, the oxide garnets YSGG and GGG and the fluoride BaY2F8.

  19. Preparation of Mo-Re-C samples containing Mo{sub 7}Re{sub 13}C with the β-Mn-type structure by solid state reaction of planetary-ball-milled powder mixtures of Mo, Re and C, and their crystal structures and superconductivity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oh-ishi, Katsuyoshi, E-mail: oh-ishi@kc.chuo-u.ac.jp; Nagumo, Kenta; Tateishi, Kazuya

    Mo-Re-C compounds containing Mo{sub 7}Re{sub 13}C with the β-Mn structure were synthesized with high-melting-temperature metals Mo, Re, and C powders using a conventional solid state method with a planetary ball milling machine instead of the arc melting method. Use of the ball milling machine was necessary to obtain Mo{sub 7}Re{sub 13}C with the β-Mn structure using the solid state method. Almost single-phase Mo{sub 7}Re{sub 13}C with a trace of impurity were obtained using the synthesis method. By XRF and lattice parameter measurements on the samples, Fe element existed in the compound synthesized using the planetary ball milling machine with amore » pot and balls made of steel, though Fe element was not detected in the compound synthesized using a pot and balls made of tungsten carbide. The former compound containg the Fe atom did not show superconductivity but the latter compound without the Fe atom showed superconductivity at 6.1 K. - Graphical abstract: Temperature dependence of the magnetic susceptibility measured under 10 Oe for the superconducting PBM-T samples without Fe element and non-superconducting PBM-S with Fe element. The inset is the enlarged view of the data for the PBM-S sample.« less

  20. Production of fungal antibiotics using polymeric solid supports in solid-state and liquid fermentation.

    PubMed

    Bigelis, Ramunas; He, Haiyin; Yang, Hui Y; Chang, Li-Ping; Greenstein, Michael

    2006-10-01

    The use of inert absorbent polymeric supports for cellular attachment in solid-state fungal fermentation influenced growth, morphology, and production of bioactive secondary metabolites. Two filamentous fungi exemplified the utility of this approach to facilitate the discovery of new antimicrobial compounds. Cylindrocarpon sp. LL-Cyan426 produced pyrrocidines A and B and Acremonium sp. LL-Cyan416 produced acremonidins A-E when grown on agar bearing moist polyester-cellulose paper and generated distinctly different metabolite profiles than the conventional shaken or stationary liquid fermentations. Differences were also apparent when tenfold concentrated methanol extracts from these fermentations were tested against antibiotic-susceptible and antibiotic-resistant Gram-positive bacteria, and zones of inhibition were compared. Shaken broth cultures of Acremonium sp. or Cylindrocarpon sp. showed complex HPLC patterns, lower levels of target compounds, and high levels of unwanted compounds and medium components, while agar/solid support cultures showed significantly increased yields of pyrrocidines A and B and acremonidins A-E, respectively. This method, mixed-phase fermentation (fermentation with an inert solid support bearing liquid medium), exploited the increase in surface area available for fungal growth on the supports and the tendency of some microorganisms to adhere to solid surfaces, possibly mimicking their natural growth habits. The production of dimeric anthraquinones by Penicillium sp. LL-WF159 was investigated in liquid fermentation using various inert polymeric immobilization supports composed of polypropylene, polypropylene cellulose, polyester-cellulose, or polyurethane. This culture produced rugulosin, skyrin, flavomannin, and a new bisanthracene, WF159-A, after fermentation in the presence and absence of polymeric supports for mycelial attachment. The physical nature of the different support systems influenced culture morphology and relative metabolite yields, as determined by HPLC analysis and measurement of antimicrobial activity. The application of such immobilized-cell fermentation methods under solid and liquid conditions facilitated the discovery of new antibiotic compounds, and offers new approaches to fungal fermentation for natural product discovery.

  1. Calcium-Iron Oxide as Energy Storage Medium in Rechargeable Oxide Batteries

    DOE PAGES

    Berger, Cornelius M.; Mahmoud, Abdelfattah; Hermann, Raphaël P.; ...

    2016-08-08

    Rechargeable oxide batteries (ROB) comprise a regenerative solid oxide cell (rSOC) and a storage medium for oxygen ions. A sealed ROB avoids pumping loss, heat loss, and gas purity expenses in comparison with conventional rSOC. However, the iron oxide base storage medium degrades during charging–discharging cycles. In comparison, CaFe 3O 5 has improved cyclability and a high reversible oxygen storage capacity of 22.3 mol%. In this paper, we analyzed the redox mechanism of this compound. After a solid-state synthesis of CaFe 3O 5, we verified the phase composition and studied the redox reaction by means of X-ray diffraction, Mössbauer spectrometry,more » and scanning electron microscopy. Finally, results show a great potential to operate the battery with this storage material during multiple charging–discharging cycles.« less

  2. FSILP: fuzzy-stochastic-interval linear programming for supporting municipal solid waste management.

    PubMed

    Li, Pu; Chen, Bing

    2011-04-01

    Although many studies on municipal solid waste management (MSW management) were conducted under uncertain conditions of fuzzy, stochastic, and interval coexistence, the solution to the conventional linear programming problems of integrating fuzzy method with the other two was inefficient. In this study, a fuzzy-stochastic-interval linear programming (FSILP) method is developed by integrating Nguyen's method with conventional linear programming for supporting municipal solid waste management. The Nguyen's method was used to convert the fuzzy and fuzzy-stochastic linear programming problems into the conventional linear programs, by measuring the attainment values of fuzzy numbers and/or fuzzy random variables, as well as superiority and inferiority between triangular fuzzy numbers/triangular fuzzy-stochastic variables. The developed method can effectively tackle uncertainties described in terms of probability density functions, fuzzy membership functions, and discrete intervals. Moreover, the method can also improve upon the conventional interval fuzzy programming and two-stage stochastic programming approaches, with advantageous capabilities that are easily achieved with fewer constraints and significantly reduces consumption time. The developed model was applied to a case study of municipal solid waste management system in a city. The results indicated that reasonable solutions had been generated. The solution can help quantify the relationship between the change of system cost and the uncertainties, which could support further analysis of tradeoffs between the waste management cost and the system failure risk. Copyright © 2010 Elsevier Ltd. All rights reserved.

  3. Microbial response to environmental gradients in a ceramic-based diffusion system.

    PubMed

    Wolfaardt, G M; Hendry, M J; Birkham, T; Bressel, A; Gardner, M N; Sousa, A J; Korber, D R; Pilaski, M

    2008-05-01

    A solid, porous matrix was used to establish steady-state concentration profiles upon which microbial responses to concentration gradients of nutrients or antimicrobial agents could be quantified. This technique relies on the development of spatially defined concentration gradients across a ceramic plate resulting from the diffusion of solutes through the porous ceramic matrix. A two-dimensional, finite-element numerical transport model was used to predict the establishment of concentration profiles, after which concentration profiles of conservative tracers were quantified fluorometrically and chemically at the solid-liquid interface to verify the simulated profiles. Microbial growth responses to nutrient, hypochloride, and antimicrobial concentration gradients were then quantified using epifluorescent or scanning confocal laser microscopy. The observed microbial response verified the establishment and maintenance of stable concentration gradients along the solid-liquid interface. These results indicate the ceramic diffusion system has potential for the isolation of heterogeneous microbial communities as well as for testing the efficacy of antimicrobial agents. In addition, the durability of the solid matrix allowed long-term investigations, making this approach preferable to conventional gel-stabilized systems that are impeded by erosion as well as expansion or shrinkage of the gel. Copyright 2008 Wiley Periodicals, Inc.

  4. Origin of giant dielectric permittivity and weak ferromagnetic behavior in (1-x)LaFeO3-xBaTiO3 (0.0 ≤ x ≤ 0.25) solid solutions

    NASA Astrophysics Data System (ADS)

    Sreenivasu, T.; Tirupathi, P.; Prabahar, K.; Suryanarayana, B.; Chandra Mouli, K.

    The solid solutions of (1-x) LaFeO3-xBaTiO3 (0.0≤x≤0.25) have been synthesized successfully by the conventional solid-state reaction method. Room temperature (RT) X-ray diffraction studies reveal the stabilization of orthorhombic phase with Pbnm space group. Complete solubility in the perovskite series was demonstrated up to x=0.25. The dielectric permittivity shows colossal dielectric constant (CDC) at RT. The doping of BaTiO3 in LaFeO3 exhibit pronounced CDC up to a composition x=0.15, further it starts to decrease. The frequency-dependent dielectric loss exhibits polaronic conduction, which can attribute to presence of multiple valence of iron. The relaxation frequency and polaronic conduction mechanism was shifted towards RT as function of x. Moreover, large magnetic moment with weak ferromagnetic behavior is observed in doped LaFeO3 solid solution, which might be the destruction of spin cycloid structure due to insertion of Ti in Fe-O-Fe network of LaFeO3.

  5. Synthesis, structure, and ionic conductivity of solid solution, Li10+δM1+δP2-δS12 (M = Si, Sn).

    PubMed

    Hori, Satoshi; Suzuki, Kota; Hirayama, Masaaki; Kato, Yuki; Saito, Toshiya; Yonemura, Masao; Kanno, Ryoji

    2014-01-01

    Solid solutions of the silicon and tin analogous phases of the superionic conductor Li(10)MP(2)S(12) (M = Si, Sn) were synthesized by a conventional solid-state reaction in an evacuated silica tube at 823 K. The ranges of the solid solutions were determined to be 0.20 < δ < 0.43 and -0.25 < δ < -0.01 in Li(10+δ)M(1+δ)P(2-δ)S(12) (0.525 ≤k≤ 0.60 and 0.67 ≤k≤ 0.75 in Li(4-k)M(1-k)PkS(4)) for the Si and Sn systems, respectively. The ionic conductivity of these systems varied as a function of the changing M ions: the Si and Sn systems showed lower conductivity than the Ge system, Li(10+δ)Ge(1+δ)P(2-δ)S(12). The conductivity change for different elements might be due to the lattice size and lithium content affecting the ionic conduction. The relationship between ionic conduction, structure, and lithium concentration is discussed based on the structural and electrochemical information for the silicon, germanium, and tin systems.

  6. Dendrite Suppression by Synergistic Combination of Solid Polymer Electrolyte Crosslinked with Natural Terpenes and Lithium-Powder Anode for Lithium-Metal Batteries.

    PubMed

    Shim, Jimin; Lee, Jae Won; Bae, Ki Yoon; Kim, Hee Joong; Yoon, Woo Young; Lee, Jong-Chan

    2017-05-22

    Lithium-metal anode has fundamental problems concerning formation and growth of lithium dendrites, which prevents practical applications of next generation of high-capacity lithium-metal batteries. The synergistic combination of solid polymer electrolyte (SPE) crosslinked with naturally occurring terpenes and lithium-powder anode is promising solution to resolve the dendrite issues by substituting conventional liquid electrolyte/separator and lithium-foil anode system. A series of SPEs based on polysiloxane crosslinked with natural terpenes are prepared by facile thiol-ene click reaction under mild condition and the structural effect of terpene crosslinkers on electrochemical properties is studied. Lithium powder with large surface area is prepared by droplet emulsion technique (DET) and used as anode material. The effect of the physical state of electrolyte (solid/liquid) and morphology of lithium-metal anode (powder/foil) on dendrite growth behavior is systematically studied. The synergistic combination of SPE and lithium-powder anode suggests an effective solution to suppress the dendrite growth owing to the formation of a stable solid-electrolyte interface (SEI) layer and delocalized current density. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Monte Carlo simulations for the free energies of C60 and C70 fullerene crystals by acceptance ratio method and expanded ensemble method

    NASA Astrophysics Data System (ADS)

    Kim, Minkyu; Chang, Jaeeon; Sandler, Stanley I.

    2014-02-01

    Accurate values of the free energies of C60 and C70 fullerene crystals are obtained using expanded ensemble method and acceptance ratio method combined with the Einstein-molecule approach. Both simulation methods, when tested for Lennard-Jones crystals, give accurate results of the free energy differing from each other in the fifth significant digit. The solid-solid phase transition temperature of C60 crystal is determined from free energy profiles, and found to be 260 K, which is in good agreement with experiment. For C70 crystal, using the potential model of Sprik et al. [Phys. Rev. Lett. 69, 1660 (1992)], low-temperature solid-solid phase transition temperature is found to be 160 K determined from the free energy profiles. Whereas this is somewhat lower than the experimental value, it is in agreement with conventional molecular simulations, which validates the methodological consistency of the present simulation method. From the calculations of the free energies of C60 and C70 crystals, we note the significance of symmetry number for crystal phase needed to properly account for the indistinguishability of orientationally disordered states.

  8. Extending the applicability of the Tkatchenko-Scheffler dispersion correction via iterative Hirshfeld partitioning

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bučko, Tomáš, E-mail: bucko@fns.uniba.sk; Department of Computational Materials Physics, Fakultät für Physik and Center for Computational Materials Science, Universität Wien, Sensengasse, Wien 1090; Lebègue, Sébastien, E-mail: sebastien.lebegue@univ-lorraine.fr

    2014-07-21

    Recently we have demonstrated that the applicability of the Tkatchenko-Scheffler (TS) method for calculating dispersion corrections to density-functional theory can be extended to ionic systems if the Hirshfeld method for estimating effective volumes and charges of atoms in molecules or solids (AIM’s) is replaced by its iterative variant [T. Bučko, S. Lebègue, J. Hafner, and J. Ángyán, J. Chem. Theory Comput. 9, 4293 (2013)]. The standard Hirshfeld method uses neutral atoms as a reference, whereas in the iterative Hirshfeld (HI) scheme the fractionally charged atomic reference states are determined self-consistently. We show that the HI method predicts more realistic AIMmore » charges and that the TS/HI approach leads to polarizabilities and C{sub 6} dispersion coefficients in ionic or partially ionic systems which are, as expected, larger for anions than for cations (in contrast to the conventional TS method). For crystalline materials, the new algorithm predicts polarizabilities per unit cell in better agreement with the values derived from the Clausius-Mosotti equation. The applicability of the TS/HI method has been tested for a wide variety of molecular and solid-state systems. It is demonstrated that for systems dominated by covalent interactions and/or dispersion forces the TS/HI method leads to the same results as the conventional TS approach. The difference between the TS/HI and TS approaches increases with increasing ionicity. A detailed comparison is presented for isoelectronic series of octet compounds, layered crystals, complex intermetallic compounds, and hydrides, and for crystals built of molecules or containing molecular anions. It is demonstrated that only the TS/HI method leads to accurate results for systems where both electrostatic and dispersion interactions are important, as illustrated for Li-intercalated graphite and for molecular adsorption on the surfaces in ionic solids and in the cavities of zeolites.« less

  9. Advances in emerging drugs for the treatment of neuroblastoma.

    PubMed

    Berlanga, Pablo; Cañete, Adela; Castel, Victoria

    2017-03-01

    Neuroblastoma is the most common solid extracranial tumor of childhood. Outcome for children with high-risk neuroblastoma remains suboptimal. More than half of children diagnosed with high-risk neuroblastoma either do not respond to conventional therapies or relapse after treatment with dismal prognosis. Areas covered: This paper presents a short review of the state of the art in the current treatment of high-risk neuroblastoma. An updated review of new targeted therapies in this group of patients is also presented. Expert opinion: In order to improve prognosis for high-risk patients there is an urgent need to better understand spatial and temporal heterogeneity and obtain new predictive preclinical models in neuroblastoma. Combination strategies with conventional chemotherapy and/or other targeted therapies may overcome current ALK inhibitors resistance. Improvement of international and transatlantic cooperation to speed clinical trials accrual is needed.

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

    NASA Technical Reports Server (NTRS)

    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.

  11. Recent advances in the science and technology for solid state lighting

    NASA Astrophysics Data System (ADS)

    Munkholm, Anneli

    2003-03-01

    Recent development of high power light emitting diodes (LEDs) has enabled fabrication of solid state devices with efficiencies that surpass that of incandescent light, as well as providing a total light output significantly exceeding that of conventional indicator LEDs. This breakthrough in high flux is opening up new applications for use of high power LEDs, such as liquid crystal display backlighting and automotive headlights. Some of the key elements to this technological breakthrough are the flip-chip device design, power packaging and phosphor coating technology, which will be discussed. In addition to device design improvements, our fundamental knowledge of the III-nitride material system is improving and has resulted in higher internal quantum efficiencies. Strain plays a significant role in complex AlInGaN heterostructures used in current devices. Using a multi-beam optical strain sensor (MOSS) system to measure the wafer curvature in situ, we have characterized the strain during metal-organic chemical vapor deposition of III-nitrides. Strain measurements of InGaN, AlGaN and Si-doped GaN films on GaN will be presented.

  12. Solid-state laser sources for remote sensing

    NASA Technical Reports Server (NTRS)

    Byer, R. L.; Kane, T.; Eggleston, J.; Long, S. Y.

    1983-01-01

    Recent progress in slab-geometry and conventional rod Nd:YAG solid-state lasers for applications in remote sensing is presented. Developments in slab geometry lasers, which were aimed at improving pulse energy and tuning range, have been based on the use of a Nd:glass substrate with a zig-zag optical path, with selective Raman shifting in gases and harmonic generation in LiNbO3 and KDP to extend the tuning range into the UV and visible regions. The theoretically predicted advantages of the elimination of birefringence and thermal and stress-induced focusing in the slab-geometry laser have been confirmed in measurements on a test-bed Nd:glass system, and a CW lamp pumped Nd:YAG oscillator, which have also demonstrated an order of magnitude improvement in laser performance. A single axial mode Nd:YAG oscillator has also been designed which, operating in a 3-msec quasi-CW mode, has a chirp rate of 30 kHz/microsec and a free-running stability of + or - 20 MHz. With chirp compensation, this stability is adequate for wind velocity measurements by coherent lidar.

  13. Modulated electron-multiplied fluorescence lifetime imaging microscope: all-solid-state camera for fluorescence lifetime imaging.

    PubMed

    Zhao, Qiaole; Schelen, Ben; Schouten, Raymond; van den Oever, Rein; Leenen, René; van Kuijk, Harry; Peters, Inge; Polderdijk, Frank; Bosiers, Jan; Raspe, Marcel; Jalink, Kees; Geert Sander de Jong, Jan; van Geest, Bert; Stoop, Karel; Young, Ian Ted

    2012-12-01

    We have built an all-solid-state camera that is directly modulated at the pixel level for frequency-domain fluorescence lifetime imaging microscopy (FLIM) measurements. This novel camera eliminates the need for an image intensifier through the use of an application-specific charge coupled device design in a frequency-domain FLIM system. The first stage of evaluation for the camera has been carried out. Camera characteristics such as noise distribution, dark current influence, camera gain, sampling density, sensitivity, linearity of photometric response, and optical transfer function have been studied through experiments. We are able to do lifetime measurement using our modulated, electron-multiplied fluorescence lifetime imaging microscope (MEM-FLIM) camera for various objects, e.g., fluorescein solution, fixed green fluorescent protein (GFP) cells, and GFP-actin stained live cells. A detailed comparison of a conventional microchannel plate (MCP)-based FLIM system and the MEM-FLIM system is presented. The MEM-FLIM camera shows higher resolution and a better image quality. The MEM-FLIM camera provides a new opportunity for performing frequency-domain FLIM.

  14. Evaluation of Origin Ensemble algorithm for image reconstruction for pixelated solid-state detectors with large number of channels

    NASA Astrophysics Data System (ADS)

    Kolstein, M.; De Lorenzo, G.; Mikhaylova, E.; Chmeissani, M.; Ariño, G.; Calderón, Y.; Ozsahin, I.; Uzun, D.

    2013-04-01

    The Voxel Imaging PET (VIP) Pathfinder project intends to show the advantages of using pixelated solid-state technology for nuclear medicine applications. It proposes designs for Positron Emission Tomography (PET), Positron Emission Mammography (PEM) and Compton gamma camera detectors with a large number of signal channels (of the order of 106). For PET scanners, conventional algorithms like Filtered Back-Projection (FBP) and Ordered Subset Expectation Maximization (OSEM) are straightforward to use and give good results. However, FBP presents difficulties for detectors with limited angular coverage like PEM and Compton gamma cameras, whereas OSEM has an impractically large time and memory consumption for a Compton gamma camera with a large number of channels. In this article, the Origin Ensemble (OE) algorithm is evaluated as an alternative algorithm for image reconstruction. Monte Carlo simulations of the PET design are used to compare the performance of OE, FBP and OSEM in terms of the bias, variance and average mean squared error (MSE) image quality metrics. For the PEM and Compton camera designs, results obtained with OE are presented.

  15. A review of the development of portable laser induced breakdown spectroscopy and its applications

    NASA Astrophysics Data System (ADS)

    Rakovský, J.; Čermák, P.; Musset, O.; Veis, P.

    2014-11-01

    In this review, we present person-transportable laser induced breakdown spectroscopy (LIBS) devices that have previously been developed and reported in the literature as well as their applications. They are compared with X-ray fluorescent (XRF) devices, which represent their strongest competition. Although LIBS devices have advantages over XRF devices, such as sensitivity to the light elements, high spatial resolution and the possibility to distinguish between different layers of the sample, there are also disadvantages and both are discussed here. Furthermore, the essential portable LIBS instrumentation (laser, spectrograph and detector) is presented, and published results related to new laser sources (diode-pumped solid-state, microchip and fiber lasers) used in LIBS are overviewed. Compared to conventional compact flashlamp pumped solid-state lasers, the new laser sources provide higher repetition rates, higher efficiency (less power consumption) and higher beam quality, resulting in higher fluences, even for lower energies, and could potentially increase the figure of merit of portable LIBS instruments. Compact spectrometers used in portable LIBS devices and their parts (spectrograph, detector) are also discussed.

  16. Development of a Solid-State Fermentation System for Producing Bioethanol from Food Waste

    NASA Astrophysics Data System (ADS)

    Honda, Hiroaki; Ohnishi, Akihiro; Fujimoto, Naoshi; Suzuki, Masaharu

    Liquid fermentation is the a conventional method of producing bioethanol. However, this method results in the formation of high concentrations waste after distillation and futher treatment requires more energy and is costly(large amounts of costly energy).Saccharification of dried raw garbage was tested for 12 types of Koji starters under the following optimum culture conditions: temperature of 30°C and initial moisture content of 50%.Among all the types, Aspergillus oryzae KBN650 had the highest saccharifying power. The ethanol-producing ability of the raw garbage was investigated for 72 strains of yeast, of which Saccharomyces cerevisiae A30 had the highest ethanol production(yield)under the following optimum conditions: 1 :1 ratio of dried garbage and saccharified garbage by weight, and initial moisture content of 60%. Thus, the solid-state fermentation system consisted of the following 4 processes: moisture control, saccharification, ethanol production and distillation. This system produced 0.6kg of ethanol from 9.6kg of garbage. Moreover the ethanol yield from all sugars was calculated to be 0.37.

  17. Effect of microwave-assisted sintering on dielectric properties of CaCu{sub 3}Ti{sub 4}O{sub 12} ceramic

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rani, Suman, E-mail: sumanranigju@gmail.com; Ahlawat, Neetu; Punia, R.

    2016-05-23

    In this present work, CaCu{sub 3}Ti{sub 4}O{sub 12} (CCTO) was synthesized by conventional solid-state reaction technique. The synthesis process was carried out in two phases; by conventional process (calcination and sintering at 1080°C for 10 hours) and phase II involves the micro assisted pre sintering of conventionally calcined CCTO for very short soaking time of 30 min at 1080°C in a microwave furnace followed by sintering at 1080°C for 10 hours in conventional furnace. X-ray diffraction (XRD) patterns confirmed the formation of single phase ceramic. Dielectric properties were studied over the frequency range from 50Hz -5MHz at temperatures (273K-343K). It wasmore » observed that pre- microwave sintering enhance the dielectric constant values from 10900 to 11893 and respectively reduces the dielectric loss values from 0.49 to 0.34 at room temperature(1 KHz). CCTO ceramics which are found desirable for many technological applications. The effect is more pronounced at low frequencies of applied electric field.« less

  18. Mechanism for enhanced absorption of a solid dispersion formulation of LY2300559 using the artificial stomach duodenum model.

    PubMed

    Polster, Christopher S; Wu, Sy-Juen; Gueorguieva, Ivelina; Sperry, David C

    2015-04-06

    An artificial stomach duodenum (ASD) model has been used to demonstrate the performance difference between two formulations of LY2300559, a low-solubility acidic developmental drug. The two formulations investigated were a conventional high-shear wet granulation (HSWG) formulation and a solid dispersion formulation. A pharmacokinetic study in humans demonstrated the enhanced performance of the solid dispersion formulation relative to the HSWG formulation. The Cmax and AUC of the solid dispersion was 2.6 and 1.9 times greater, respectively, compared to the HSWG formulation. In the ASD, the solid dispersion formulation performance was characterized by three main phases: (1) rapid release in the stomach, creating a supersaturated concentration of drug, (2) precipitation in the stomach, and (3) rapid redissolution of the precipitate in the duodenum to concentration levels that are supersaturated relative to crystalline drug. A series of complementary experiments were employed to describe this performance behavior mechanistically. Imaging experiments with a pH indicating dye showed that local pH gradients from meglumine in the solid dispersion formulation were responsible for creating a high initial supersaturation concentration in the stomach. Upon dissipation of meglumine, the drug precipitated in the stomach as an amorphous solid. Because the precipitated drug is in an amorphous form, it can then rapidly redissolve as it transits to the more neutral environment of the duodenum. This unexpected sequence of physical state changes gives a mechanistic explanation for the enhanced in vivo performance of the solid dispersion formulation relative to the HSWG formulation.

  19. DNA extraction on bio-chip: history and preeminence over conventional and solid-phase extraction methods.

    PubMed

    Ayoib, Adilah; Hashim, Uda; Gopinath, Subash C B; Md Arshad, M K

    2017-11-01

    This review covers a developmental progression on early to modern taxonomy at cellular level following the advent of electron microscopy and the advancement in deoxyribonucleic acid (DNA) extraction for expatiation of biological classification at DNA level. Here, we discuss the fundamental values of conventional chemical methods of DNA extraction using liquid/liquid extraction (LLE) followed by development of solid-phase extraction (SPE) methods, as well as recent advances in microfluidics device-based system for DNA extraction on-chip. We also discuss the importance of DNA extraction as well as the advantages over conventional chemical methods, and how Lab-on-a-Chip (LOC) system plays a crucial role for the future achievements.

  20. Dynamic modelling of solids in a full-scale activated sludge plant preceded by CEPT as a preliminary step for micropollutant removal modelling.

    PubMed

    Baalbaki, Zeina; Torfs, Elena; Maere, Thomas; Yargeau, Viviane; Vanrolleghem, Peter A

    2017-04-01

    The presence of micropollutants in the environment has triggered research on quantifying and predicting their fate in wastewater treatment plants (WWTPs). Since the removal of micropollutants is highly related to conventional pollutant removal and affected by hydraulics, aeration, biomass composition and solids concentration, the fate of these conventional pollutants and characteristics must be well predicted before tackling models to predict the fate of micropollutants. In light of this, the current paper presents the dynamic modelling of conventional pollutants undergoing activated sludge treatment using a limited set of additional daily composite data besides the routine data collected at a WWTP over one year. Results showed that as a basis for modelling, the removal of micropollutants, the Bürger-Diehl settler model was found to capture the actual effluent total suspended solids (TSS) concentrations more efficiently than the Takács model by explicitly modelling the overflow boundary. Results also demonstrated that particular attention must be given to characterizing incoming TSS to obtain a representative solids balance in the presence of a chemically enhanced primary treatment, which is key to predict the fate of micropollutants.

  1. Impact of conventional or intensive milk replacer programs on Holstein heifer performance through six months of age and during first lactation.

    PubMed

    Raeth-Knight, M; Chester-Jones, H; Hayes, S; Linn, J; Larson, R; Ziegler, D; Ziegler, B; Broadwater, N

    2009-02-01

    The objectives were to evaluate the impact of conventional or intensive milk replacer (MR) feeding programs on heifer calf performance through 6 mo of age, age at first calving, and first lactation performance. At 3 (+/-1 d) d of age, 133 Holstein heifer calves from 3 commercial dairy farms were randomly assigned, within calf source, to a conventional [20% crude protein (CP), 20% fat] or intensive MR (28% CP, 18% fat). Milk replacer treatments and percent solids were 1) conventional nonacidified (CNA), 13.9%; 2) conventional acidified (CA), 13.9%; 3) modified intensive high solids (IHS), 16.7%; 4) modified intensive low solids (ILS), 12.5%; and 5) intensive high solids, high feeding (IHSHF), 16.7%. Calves were individually housed and remained on trial for 56 d. At 2 mo of age, heifers were grouped in pens by treatment with 6 heifers per pen (4 pens per treatment). An 18.1% CP grower concentrate mix (dry matter basis) was fed to heifers that received a conventional MR and a 21.2% CP grower concentrate mix was fed to heifers that received the intensive MR preweaning. Heifers were offered 2.45 kg/d (dry matter basis) of their respective grower concentrate mix for 112 d plus free access to hay and water. At approximately 24 wk of age, heifers were transported to a second-stage grower before returning to their respective farms approximately 1 mo before calving. First-lactation performance was determined using Dairy Herd Improvement Association records. The IHSHF treatment resulted in increased calf body weight and hip height during the preweaning and early postweaning (PEP) period and the postweaning heifer grower (PHG) period as compared with the conventional (CNA and CA) or modified intensive MR treatments (IHS and ILS). Calves receiving the IHS treatment were heavier at d 56 of the PEP period compared with the conventional or ILS treatments; however, this growth advantage was not maintained in the PHG period. Feed cost per kilogram of gain during the PEP period was lowest for CNA and CA, intermediate for IHS and ILS, and highest for the IHSHF treatment. There was no effect of MR feeding program on first-lactation performance; however, heifers that received the IHSHF MR preweaning calved 27.5 d earlier than those fed a conventional MR.

  2. Overcoming the black body limit in plasmonic and graphene near-field thermophotovoltaic systems.

    PubMed

    Ilic, Ognjen; Jablan, Marinko; Joannopoulos, John D; Celanovic, Ivan; Soljacić, Marin

    2012-05-07

    Near-field thermophotovoltaic (TPV) systems with carefully tailored emitter-PV properties show large promise for a new temperature range (600 – 1200K) solid state energy conversion, where conventional thermoelectric (TE) devices cannot operate due to high temperatures and far-field TPV schemes suffer from low efficiency and power density. We present a detailed theoretical study of several different implementations of thermal emitters using plasmonic materials and graphene. We find that optimal improvements over the black body limit are achieved for low bandgap semiconductors and properly matched plasmonic frequencies. For a pure plasmonic emitter, theoretically predicted generated power density of 14 W/cm2 and efficiency of 36% can be achieved at 600K (hot-side), for 0.17eV bandgap (InSb). Developing insightful approximations, we argue that large plasmonic losses can, contrary to intuition, be helpful in enhancing the overall near-field transfer. We discuss and quantify the properties of an optimal near-field photovoltaic (PV) diode. In addition, we study plasmons in graphene and show that doping can be used to tune the plasmonic dispersion relation to match the PV cell bangap. In case of graphene, theoretically predicted generated power density of 6(120) W/cm2 and efficiency of 35(40)% can be achieved at 600(1200)K, for 0.17eV bandgap. With the ability to operate in intermediate temperature range, as well as high efficiency and power density, near-field TPV systems have the potential to complement conventional TE and TPV solid state heat-to-electricity conversion devices.

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

    NASA Astrophysics Data System (ADS)

    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.

  4. Digital Cellular Solid Pressure Vessels: A Novel Approach for Human Habitation in Space

    NASA Technical Reports Server (NTRS)

    Cellucci, Daniel; Jenett, Benjamin; Cheung, Kenneth C.

    2017-01-01

    It is widely assumed that human exploration beyond Earth's orbit will require vehicles capable of providing long duration habitats that simulate an Earth-like environment - consistent artificial gravity, breathable atmosphere, and sufficient living space- while requiring the minimum possible launch mass. This paper examines how the qualities of digital cellular solids - high-performance, repairability, reconfigurability, tunable mechanical response - allow the accomplishment of long-duration habitat objectives at a fraction of the mass required for traditional structural technologies. To illustrate the impact digital cellular solids could make as a replacement to conventional habitat subsystems, we compare recent proposed deep space habitat structural systems with a digital cellular solids pressure vessel design that consists of a carbon fiber reinforced polymer (CFRP) digital cellular solid cylindrical framework that is lined with an ultra-high molecular weight polyethylene (UHMWPE) skin. We use the analytical treatment of a linear specific modulus scaling cellular solid to find the minimum mass pressure vessel for a structure and find that, for equivalent habitable volume and appropriate safety factors, the use of digital cellular solids provides clear methods for producing structures that are not only repairable and reconfigurable, but also higher performance than their conventionally manufactured counterparts.

  5. Progress and prospect on failure mechanisms of solid-state lithium batteries

    NASA Astrophysics Data System (ADS)

    Ma, Jun; Chen, Bingbing; Wang, Longlong; Cui, Guanglei

    2018-07-01

    By replacing traditional liquid organic electrolyte with solid-state electrolyte, the solid-state lithium batteries powerfully come back to the energy storage field due to their eminent safety and energy density. In recent years, a variety of solid-state lithium batteries based on excellent solid-state electrolytes are developed. However, the performance degradation of solid-state lithium batteries during cycling and storing is still a serious challenge for practical application. Therefore, this review summarizes the research progress of solid-state lithium batteries from the perspectives of failure phenomena and failure mechanisms. Additionally, the development of methodologies on studying the failure mechanisms of solid-state lithium batteries is also reviewed. Moreover, some perspectives on the remaining questions for understanding the failure behaviors and achieving long cycle life, high safety and high energy density solid-state lithium batteries are presented. This review will help researchers to recognize the status of solid-state lithium batteries objectively and attract much more research interest in conquering the failure issues of solid-state lithium batteries.

  6. Solid oxide fuel cells fueled with reducible oxides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chuang, Steven S.; Fan, Liang Shih

    A direct-electrochemical-oxidation fuel cell for generating electrical energy includes a cathode provided with an electrochemical-reduction catalyst that promotes formation of oxygen ions from an oxygen-containing source at the cathode, a solid-state reduced metal, a solid-state anode provided with an electrochemical-oxidation catalyst that promotes direct electrochemical oxidation of the solid-state reduced metal in the presence of the oxygen ions to produce electrical energy, and an electrolyte disposed to transmit the oxygen ions from the cathode to the solid-state anode. A method of operating a solid oxide fuel cell includes providing a direct-electrochemical-oxidation fuel cell comprising a solid-state reduced metal, oxidizing themore » solid-state reduced metal in the presence of oxygen ions through direct-electrochemical-oxidation to obtain a solid-state reducible metal oxide, and reducing the solid-state reducible metal oxide to obtain the solid-state reduced metal.« less

  7. Phosphorus-31 MRI of bones using quadratic echo line-narrowing

    NASA Astrophysics Data System (ADS)

    Frey, Merideth; Barrett, Sean; Insogna, Karl; Vanhouten, Joshua

    2012-02-01

    There is a great need to probe the internal composition of bone on the sub-0.1 mm length scale, both to study normal features and to look for signs of disease. Despite the obvious importance of the mineral fraction to the biomechanical properties of skeletal tissue, few non-destructive techniques are available to evaluate changes in its chemical structure and functional microarchitecture on the interior of bones. MRI would be an excellent candidate, but bone is a particularly challenging tissue to study given the relatively low water density and wider linewidths of its solid components. Recent fundamental research in quantum computing gave rise to a new NMR pulse sequence - the quadratic echo - that can be used to narrow the broad NMR spectrum of solids. This offers a new route to do high spatial resolution, 3D ^31P MRI of bone that complements conventional MRI and x-ray based techniques to study bone physiology and structure. We have used our pulse sequence to do 3D ^31P MRI of ex vivo bones with a spatial resolution of (sub-450 μm)^3, limited only by the specifications of a conventional 4 Tesla liquid-state MRI system. We will describe our plans to push this technique towards the factor of 1000 increase in spatial resolution imposed by fundamental limits.

  8. Dry-grind processing using amylase corn and superior yeast to reduce the exogenous enzyme requirements in bioethanol production.

    PubMed

    Kumar, Deepak; Singh, Vijay

    2016-01-01

    Conventional corn dry-grind ethanol production process requires exogenous alpha and glucoamylases enzymes to breakdown starch into glucose, which is fermented to ethanol by yeast. This study evaluates the potential use of new genetically engineered corn and yeast, which can eliminate or minimize the use of these external enzymes, improve the economics and process efficiencies, and simplify the process. An approach of in situ ethanol removal during fermentation was also investigated for its potential to improve the efficiency of high-solid fermentation, which can significantly reduce the downstream ethanol and co-product recovery cost. The fermentation of amylase corn (producing endogenous α-amylase) using conventional yeast and no addition of exogenous α-amylase resulted in ethanol concentration of 4.1 % higher compared to control treatment (conventional corn using exogenous α-amylase). Conventional corn processed with exogenous α-amylase and superior yeast (producing glucoamylase or GA) with no exogenous glucoamylase addition resulted in ethanol concentration similar to control treatment (conventional yeast with exogenous glucoamylase addition). Combination of amylase corn and superior yeast required only 25 % of recommended glucoamylase dose to complete fermentation and achieve ethanol concentration and yield similar to control treatment (conventional corn with exogenous α-amylase, conventional yeast with exogenous glucoamylase). Use of superior yeast with 50 % GA addition resulted in similar increases in yield for conventional or amylase corn of approximately 7 % compared to that of control treatment. Combination of amylase corn, superior yeast, and in situ ethanol removal resulted in a process that allowed complete fermentation of 40 % slurry solids with only 50 % of exogenous GA enzyme requirements and 64.6 % higher ethanol yield compared to that of conventional process. Use of amylase corn and superior yeast in the dry-grind processing industry can reduce the total external enzyme usage by more than 80 %, and combining their use with in situ removal of ethanol during fermentation allows efficient high-solid fermentation.

  9. Anaerobic digestion of municipal solid waste: Technical developments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rivard, C.J.

    1996-01-01

    The anaerobic biogasification of organic wastes generates two useful products: a medium-Btu fuel gas and a compost-quality organic residue. Although commercial-scale digestion systems are used to treat municipal sewage wastes, the disposal of solid organic wastes, including municipal solid wastes (MSW), requires a more cost-efficient process. Modern biogasification systems employ high-rate, high-solids fermentation methods to improve process efficiency and reduce capital costs. The design criteria and development stages are discussed. These systems are also compared with conventional low-solids fermentation technology.

  10. European scientific notes. Volume 38. Number 1. Monthly publication

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shaffer, L.E.

    1984-01-01

    Topics include: Gender-mixed Crews on Dutch Combat Ships; Max-Planck-Institute for Psycholinguistics; Cancer Therapy with Magnetism; 9th European Underwater Biomedical Society Convention; International Center for Genetic Engineering and Biotechnology; Biotechnological Route to Polyphenylene; 2nd Romania-US Seminar on Polymer Chemistry; Statistical Climatology; A Code for Generating Dynamic Models of Robots; Fifth Generation Computing Systems; New Data Logger; Erosion by Liquid and Solid Impact, ELSI VI; Physical Chemistry of the Solid State -- Metals and alloys; NATO Buys a New Oceanographic Research Vessel; Oceanexpo/Oceantropigues 1984; Progress in Development of Wave Energy to Generate Electricity; IAPSO Symposia and Oceanography at the 18th IUGG; Newmore » Decision Support System; High Energy Channeling Research in Switzerland; Muon-Catalyzed Fusion; 2nd International Symposium on Acoustic Remote Sensing of the Atmosphere and Ocean; and Support of Science Research by the British Military.« less

  11. Hybrid Circuits with Nanofluidic Diodes and Load Capacitors

    NASA Astrophysics Data System (ADS)

    Ramirez, P.; Garcia-Morales, V.; Gomez, V.; Ali, M.; Nasir, S.; Ensinger, W.; Mafe, S.

    2017-06-01

    The chemical and physical input signals characteristic of micro- and nanofluidic devices operating in ionic solutions should eventually be translated into output electric currents and potentials that are monitored with solid-state components. This crucial step requires the design of hybrid circuits showing robust electrical coupling between ionic solutions and electronic elements. We study experimentally and theoretically the connectivity of the nanofluidic diodes in single-pore and multipore membranes with conventional capacitor systems for the cases of constant, periodic, and white-noise input potentials. The experiments demonstrate the reliable operation of these hybrid circuits over a wide range of membrane resistances, electrical capacitances, and solution p H values. The model simulations are based on empirical equations that have a solid physical basis and provide a convenient description of the electrical circuit operation. The results should contribute to advance signal transduction and processing using nanopore-based biosensors and bioelectronic interfaces.

  12. Analyses of moisture in polymers and composites

    NASA Technical Reports Server (NTRS)

    Ryan, L. E.; Vaughan, R. W.

    1980-01-01

    A suitable method for the direct measurement of moisture concentrations after humidity/thermal exposure on state of the art epoxy and polyimide resins and their graphite and glass fiber reinforcements was investigated. Methods for the determination of moisture concentration profiles, moisture diffusion modeling and moisture induced chemical changes were examined. Carefully fabricated, precharacterized epoxy and polyimide neat resins and their AS graphite and S glass reinforced composites were exposed to humid conditions using heavy water (D20), at ambient and elevated temperatures. These specimens were fixtured to theoretically limit the D20 permeation to a unidirectional penetration axis. The analytical techniques evaluated were: (1) laser pyrolysis gas chromatography mass spectrometry; (2) solids probe mass spectrometry; (3) laser pyrolysis conventional infrared spectroscopy; and (4) infrared imaging thermovision. The most reproducible and sensitive technique was solids probe mass spectrometry. The fabricated exposed specimens were analyzed for D20 profiling after humidity/thermal conditioning at three exposure time durations.

  13. Production and characterization of pure cryogenic inertial fusion targets

    NASA Astrophysics Data System (ADS)

    Boyd, B. A.; Kamerman, G. W.

    An experimental cryogenic inertial fusion target generator and two optical techniques for automated target inspection are described. The generator produces 100 microns diameter solid hydrogen spheres at a rate compatible with fueling requirements of conceptual inertial fusion power plants. A jet of liquified hydrogen is disrupted into droplets by an ultrasonically excited nozzle. The droplets solidify into microspheres while falling through a chamber maintained below the hydrogen triple point pressure. Stable operation of the generator has been demonstrated for up to three hours. The optical inspection techniques are computer aided photomicrography and coarse diffraction pattern analysis (CDPA). The photomicrography system uses a conventional microscope coupled to a computer by a solid state camera and digital image memory. The computer enhances the stored image and performs feature extraction to determine pellet parameters. The CDPA technique uses Fourier transform optics and a special detector array to perform optical processing of a target image.

  14. Alternatives for joining Si wafers to strain-accommodating Cu for high-power electronics

    NASA Astrophysics Data System (ADS)

    Faust, Nicholas; Messler, Robert W.; Khatri, Subhash

    2001-10-01

    Differences in the coefficients of thermal expansion (CTE) between silicon wafers and underlying copper electrodes have led to the use of purely mechanical dry pressure contacts for primary electrical and thermal connections in high-power solid-state electronic devices. These contacts are limited by their ability to dissipate I2R heat from within the device and by their thermal fatigue life. To increase heat dissipation and effectively deal with the CTE mismatch, metallurgical bonding of the silicon to a specially-structured, strain-accommodating copper electrode has been proposed. This study was intended to seek alternative methods for and demonstrate the feasibility of bonding Si to structured Cu in high-power solid-state devices. Three different but fundamentally related fluxless approaches identified and preliminarily assessed were: (1) conventional Sn-Ag eutectic solder; (2) a new, commercially-available active solder based on the Sn-Ag eutectic; and (3) solid-liquid interdiffusion bonding using the Au-In system. Metallurgical joints were made with varying quality levels (according to nonde-structive ultrasonic C-scan mapping, SEM, and electron microprobe) using each approach. Mechanical shear testing resulted in cohesive failure within the Si or the filler alloys. The best approach, in which eutectic Sn-Ag solder in pre-alloyed foil form was employed on Si and Cu substrates metallized (from the substrate outward) with Ti, Ni and Au, exhibited joint thermal conduction 74% better than dry pressure contacts.

  15. Experimental cocrystal screening and solution based scale-up cocrystallization methods.

    PubMed

    Malamatari, Maria; Ross, Steven A; Douroumis, Dennis; Velaga, Sitaram P

    2017-08-01

    Cocrystals are crystalline single phase materials composed of two or more different molecular and/or ionic compounds generally in a stoichiometric ratio which are neither solvates nor simple salts. If one of the components is an active pharmaceutical ingredient (API), the term pharmaceutical cocrystal is often used. There is a growing interest among drug development scientists in exploring cocrystals, as means to address physicochemical, biopharmaceutical and mechanical properties and expand solid form diversity of the API. Conventionally, coformers are selected based on crystal engineering principles, and the equimolar mixtures of API and coformers are subjected to solution-based crystallization that are commonly employed in polymorph and salt screening. However, the availability of new knowledge on cocrystal phase behaviour in solid state and solutions has spurred the development and implementation of more rational experimental cocrystal screening as well as scale-up methods. This review aims to provide overview of commonly employed solid form screening techniques in drug development with an emphasis on cocrystal screening methodologies. The latest developments in understanding and the use of cocrystal phase diagrams in both screening and solution based scale-up methods are also presented. Final section is devoted to reviewing the state of the art research covering solution based scale-up cocrystallization process for different cocrystals besides more recent continuous crystallization methods. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. A Li-Garnet composite ceramic electrolyte and its solid-state Li-S battery

    NASA Astrophysics Data System (ADS)

    Huang, Xiao; Liu, Cai; Lu, Yang; Xiu, Tongping; Jin, Jun; Badding, Michael E.; Wen, Zhaoyin

    2018-04-01

    A high strength Li-Garnet solid electrolyte composite ceramic is successfully prepared via conventional solid state method with Li6.4La3Zr1.4Ta0.6O12 and nano MgO powders. Well sintered ceramic pellets and bars are obtained with 0-9 wt.% MgO. Fracture strength is approximately 135 MPa for composite ceramics with 5-9 wt.% MgO, which is ∼50% higher than that of pure Li6.4La3Zr1.4Ta0.6O12 (90 MPa). Lithium-ion conductivity of the composite is above 5 × 10-4 S cm-1 at room temperature; comparable to the pure Li6.4La3Zr1.4Ta0.6O12 material. SEM cross-sections of the composite ceramic shows a much more uniform microstructure comparing with pure ones, owing to the grain growth inhibition effect of the MgO second phase. A battery cell consisting of Li/composite ceramics/Sulfur-Carbon at 25 °C exhibits a capacity of 685 mAh g-1 at 0.2 C at the 200th cycle, while maintaining a coulombic efficiency of 100%. These results indicate that the composite ceramic Li6.4La3Zr1.4Ta0.6O12-MgO is promising for the production of electrolyte membrane and fabrication of Li-Sulfur batteries.

  17. Diagnostic performances of shear wave elastography: which parameter to use in differential diagnosis of solid breast masses?

    PubMed

    Lee, Eun Jung; Jung, Hae Kyoung; Ko, Kyung Hee; Lee, Jong Tae; Yoon, Jung Hyun

    2013-07-01

    To evaluate which shear wave elastography (SWE) parameter proves most accurate in the differential diagnosis of solid breast masses. One hundred and fifty-six breast lesions in 139 consecutive women (mean age: 43.54 ± 9.94 years, range 21-88 years), who had been scheduled for ultrasound-guided breast biopsy, were included. Conventional ultrasound and SWE were performed in all women before biopsy procedures. Ultrasound BI-RADS final assessment and SWE parameters were recorded. Diagnostic performance of each SWE parameter was calculated and compared with those obtained when applying cut-off values of previously published data. Performance of conventional ultrasound and ultrasound combined with each parameter was also compared. Of the 156 breast masses, 120 (76.9 %) were benign and 36 (23.1 %) malignant. Maximum stiffness (Emax) with a cut-off of 82.3 kPa had the highest area under the receiver operating characteristics curve (Az) value compared with other SWE parameters, 0.860 (sensitivity 88.9 %, specificity 77.5 %, accuracy 80.1 %). Az values of conventional ultrasound combined with each SWE parameter showed lower (but not significantly) values than with conventional ultrasound alone. Maximum stiffness (82.3 kPa) provided the best diagnostic performance. However the overall diagnostic performance of ultrasound plus SWE was not significantly better than that of conventional ultrasound alone. • SWE offers new information over and above conventional breast ultrasound • Various SWE parameters were explored regarding distinction between benign and malignant lesions • An elasticity of 82.3 kPa appears optimal in differentiating solid breast masses • However, ultrasound plus SWE was not significantly better than conventional ultrasound alone.

  18. Advanced Protection & Service Restoration for FREEDM Systems

    NASA Astrophysics Data System (ADS)

    Singh, Urvir

    A smart electric power distribution system (FREEDM system) that incorporates DERs (Distributed Energy Resources), SSTs (Solid State Transformers - that can limit the fault current to two times of the rated current) & RSC (Reliable & Secure Communication) capabilities has been studied in this work in order to develop its appropriate protection & service restoration techniques. First, a solution is proposed that can make conventional protective devices be able to provide effective protection for FREEDM systems. Results show that although this scheme can provide required protection but it can be quite slow. Using the FREEDM system's communication capabilities, a communication assisted Overcurrent (O/C) protection scheme is proposed & results show that by using communication (blocking signals) very fast operating times are achieved thereby, mitigating the problem of conventional O/C scheme. Using the FREEDM System's DGI (Distributed Grid Intelligence) capability, an automated FLISR (Fault Location, Isolation & Service Restoration) scheme is proposed that is based on the concept of 'software agents' & uses lesser data (than conventional centralized approaches). Test results illustrated that this scheme is able to provide a global optimal system reconfiguration for service restoration.

  19. Comparative treatment effectiveness of conventional trench and seepage pit systems.

    PubMed

    Field, J P; Farrell-Poe, K L; Walworth, J L

    2007-03-01

    On-site wastewater treatment systems can be a potential source of groundwater contamination in regions throughout the United States and other parts of the world. Here, we evaluate four conventional trench systems and four seepage pit systems to determine the relative effectiveness of these systems for the treatment of septic tank effluent in medium- to coarse-textured arid and semiarid soils. Soil borings were advanced up to twice the depth of the trenches (4 m) and seepage pits (15 m) at two horizontal distances (30 cm and 1.5 m) from the sidewalls of the systems. Soil samples were analyzed for various biological and chemical parameters, including Escherichia coli, total coliform, pH, total organic carbon, total dissolved solids, total nitrogen, ammonium-nitrogen, and nitrate-nitrogen. Most soil parameters investigated approached background levels more rapidly near the trenches than the seepage pits, as sampling distance increased both vertically and horizontally from the sidewalls of the systems.

  20. Mathematical Simulation for Integrated Linear Fresnel Spectrometer Chip

    NASA Technical Reports Server (NTRS)

    Park, Yeonjoon; Yoon, Hargoon; Lee, Uhn; King, Glen C.; Choi, Sang H.

    2012-01-01

    A miniaturized solid-state optical spectrometer chip was designed with a linear gradient-gap Fresnel grating which was mounted perpendicularly to a sensor array surface and simulated for its performance and functionality. Unlike common spectrometers which are based on Fraunhoffer diffraction with a regular periodic line grating, the new linear gradient grating Fresnel spectrometer chip can be miniaturized to a much smaller form-factor into the Fresnel regime exceeding the limit of conventional spectrometers. This mathematical calculation shows that building a tiny motionless multi-pixel microspectrometer chip which is smaller than 1 cubic millimter of optical path volume is possible. The new Fresnel spectrometer chip is proportional to the energy scale (hc/lambda), while the conventional spectrometers are proportional to the wavelength scale (lambda). We report the theoretical optical working principle and new data collection algorithm of the new Fresnel spectrometer to build a compact integrated optical chip.

  1. Examination of the Reelfoot Rift Petroleum System, south-central United States, and the elements that remain for potential exploration and development

    USGS Publications Warehouse

    Coleman, James; Pratt, Thomas L.

    2016-01-01

    No production has been established in the Reel-foot rift. However, at least nine of 22 exploratory wells have reported petroleum shows, mainly gas shows with some asphalt or solid hydrocarbon residue. Regional seismic profiling shows the presence of two large inversion structures (Blytheville arch and Pascola arch). The Blytheville arch is marked by a core of structurally thickened Elvins Shale, whereas the Pascola arch reflects the structural uplift of a portion of the entire rift basin. Structural uplift and faulting within the Reelfoot rift since the late Paleozoic appear to have disrupted older conventional hydrocarbon traps and likely spilled any potential conventional petroleum accumulations. The remaining potential resources within the Reelfoot rift are likely shale gas accumulations within the Elvins Shale; however, reservoir continuity and porosity as well as pervasive faulting appear to be significant future challenges for explorers and drillers.

  2. Improved design of anaerobic digesters for household biogas production in indonesia: one cow, one digester, and one hour of cooking per day.

    PubMed

    Usack, Joseph G; Wiratni, Wiratni; Angenent, Largus T

    2014-01-01

    A government-sponsored initiative in Indonesia to design and implement low-cost anaerobic digestion systems resulted in 21 full-scale systems with the aim to satisfy the cooking fuel demands of rural households owning at least one cow. The full-scale design consisted of a 0.3 m diameter PVC pipe, which was operated as a conventional plug-flow system. The system generated enough methane to power a cooking stove for ∼ 1 h. However, eventual clogging from solids accumulation inside the bioreactor proved to be a major drawback. Here, we improved the digester configuration to remedy clogging while maintaining system performance. Controlled experiments were performed using four 9-L laboratory-scale digesters operated at a temperature of 27 ± 1 °C, a volatile solids loading rate of 2.0 g VS · L(-1) · day(-1), and a 21-day hydraulic retention time. Two of the digesters were replicates of the original design (control digesters), while the other two digesters included internal mixing or effluent recycle (experimental digesters). The performance of each digester was compared based on methane yields, VS removal efficiencies, and steady-state solids concentrations during an operating period of 311 days. Statistical analyses revealed that internal mixing and effluent recycling resulted in reduced solids accumulation compared to the controls without diminishing methane yields or solids removal efficiencies.

  3. Feasibility study of solid oxide fuel cell engines integrated with sprinter gas turbines: Modeling, design and control

    NASA Astrophysics Data System (ADS)

    Jia, Zhenzhong; Sun, Jing; Dobbs, Herb; King, Joel

    2015-02-01

    Conventional recuperating solid oxide fuel cell (SOFC)/gas turbine (GT) system suffers from its poor dynamic capability and load following performance. To meet the fast, safe and efficient load following requirements for mobile applications, a sprinter SOFC/GT system concept is proposed in this paper. In the proposed system, an SOFC stack operating at fairly constant temperature provides the baseline power with high efficiency while the fast dynamic capability of the GT-generator is fully explored for fast dynamic load following. System design and control studies have been conducted by using an SOFC/GT system model consisting of experimentally-verified component models. In particular, through analysis of the steady-state simulation results, an SOFC operation strategy is proposed to maintain fairly constant SOFC power (less than 2% power variation) and temperature (less than 2 K temperature variation) over the entire load range. A system design procedure well-suited to the proposed system has also been developed to help determining component sizes and the reference steady-state operation line. In addition, control analysis has been studied for both steady-state and transient operations. Simulation results suggest that the proposed system holds the promise to achieve fast and safe transient operations by taking full advantage of the fast dynamics of the GT-generator.

  4. High-resolution magnetic resonance spectroscopy using a solid-state spin sensor

    NASA Astrophysics Data System (ADS)

    Glenn, David R.; Bucher, Dominik B.; Lee, Junghyun; Lukin, Mikhail D.; Park, Hongkun; Walsworth, Ronald L.

    2018-03-01

    Quantum systems that consist of solid-state electronic spins can be sensitive detectors of nuclear magnetic resonance (NMR) signals, particularly from very small samples. For example, nitrogen–vacancy centres in diamond have been used to record NMR signals from nanometre-scale samples, with sensitivity sufficient to detect the magnetic field produced by a single protein. However, the best reported spectral resolution for NMR of molecules using nitrogen–vacancy centres is about 100 hertz. This is insufficient to resolve the key spectral identifiers of molecular structure that are critical to NMR applications in chemistry, structural biology and materials research, such as scalar couplings (which require a resolution of less than ten hertz) and small chemical shifts (which require a resolution of around one part per million of the nuclear Larmor frequency). Conventional, inductively detected NMR can provide the necessary high spectral resolution, but its limited sensitivity typically requires millimetre-scale samples, precluding applications that involve smaller samples, such as picolitre-volume chemical analysis or correlated optical and NMR microscopy. Here we demonstrate a measurement technique that uses a solid-state spin sensor (a magnetometer) consisting of an ensemble of nitrogen–vacancy centres in combination with a narrowband synchronized readout protocol to obtain NMR spectral resolution of about one hertz. We use this technique to observe NMR scalar couplings in a micrometre-scale sample volume of approximately ten picolitres. We also use the ensemble of nitrogen–vacancy centres to apply NMR to thermally polarized nuclear spins and resolve chemical-shift spectra from small molecules. Our technique enables analytical NMR spectroscopy at the scale of single cells.

  5. Algorithm to illustrate context using dynamic lighting effects

    NASA Astrophysics Data System (ADS)

    John, Roshy M.; Balasubramanian, T.

    2007-09-01

    With the invention of Ultra-Bright LED, solid state lighting has come to something which is much more efficient and energy saving when compared to conventional incandescent or fluorescent lighting. With the use of proper driver electronics now a days it is possible to install solid state lighting systems with the cost same as that of any other lighting technology. This paper is a part of the research project we are doing in our lab, which deals with using ultra bright LEDs of different colors for lighting applications. The driver electronics are made in such a way that, the color and brightness of the lights will change according to context. For instance, if one of the users is reading a story or listening to music in a Personal Computer or in a hand held device such as a PDA, the lighting systems and the HVAC (Heating Ventilation Air-conditioning) systems will change dramatically according to the content of the story or the music. The vulnerability of solid-state lighting helps to accomplish such an effect. Such a type of system will help the reader to feel the story mentally and physically as well. We developed complete driver electronics for the system using multiple microcomputers and a full software suite which uses complex algorithms to decode the context from text or music and synchronize it to lighting and HVAC information. The paper also presents some case-study statistics which shows the advantage of using the system to teach kindergarten children, deaf and dumb children and for language learning classes.

  6. Solution-processable glass LiI-Li 4SnS 4 superionic conductors for all-solid-state Li-ion batteries

    DOE PAGES

    Kern Ho Park; Oh, Dae Yang; Choi, Young Eun; ...

    2015-12-22

    The new, highly conductive (4.1 × 10 –4 S cm –1 at 30 °C), highly deformable, and dry-air-stable glass 0.4LiI-0.6Li 4SnS 4 is prepared using a homogeneous methanol solution. Furthermore, the solution process enables the wetting of any exposed surface of the active materials with highly conductive solidified electrolytes (0.4LiI-0.6Li 4SnS 4), resulting in considerable improvements in electrochemical performances of these electrodes over conventional mixture electrodes.

  7. Plasmon-assisted radiolytic energy conversion in aqueous solutions

    PubMed Central

    Kim, Baek Hyun; Kwon, Jae W.

    2014-01-01

    The field of conventional energy conversion using radioisotopes has almost exclusively focused on solid-state materials. Herein, we demonstrate that liquids can be an excellent media for effective energy conversion from radioisotopes. We also show that free radicals in liquid, which are continuously generated by beta radiation, can be utilized for electrical energy generation. Under beta radiation, surface plasmon obtained by the metallic nanoporous structures on TiO2 enhanced the radiolytic conversion via the efficient energy transfer between plasmons and free radicals. This work introduces a new route for the development of next-generation power sources. PMID:24918356

  8. Printed Antennas Made Reconfigurable by Use of MEMS Switches

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.

    2005-01-01

    A class of reconfigurable microwave antennas now undergoing development comprise fairly conventional printed-circuit feed elements and radiating patches integrated with novel switches containing actuators of the microelectromechanical systems (MEMS) type. In comparison with solid-state electronic control devices incorporated into some prior printed microwave antennas, the MEMS-based switches in these antennas impose lower insertion losses and consume less power. Because the radio-frequency responses of the MEMS switches are more nearly linear, they introduce less signal distortion. In addition, construction and operation are simplified because only a single DC bias line is needed to control each MEMS actuator.

  9. Arthritis inflammation monitored by subcutaneous millimeter wave thermography.

    PubMed

    Edrich, J; Smyth, C J

    1978-01-01

    A new technique for remote, noninvasive mapping of temperature elevations of the human joints is described; it uses the mm wave radiation emitted by the human body. A solid state switched scanner for 68 GHz is described which overcomes the depth limitations of conventional, infrared thermographs and can measure to subcutaneous depths of several mm with a temperature resolution of 0.25 degrees C. Measurements on rheumatoid arthritic knee joints are presented which show little correlation with simultaneously measured skin temperatures. Significant longterm thermographic changes induced by steroid injection indicate a potential for objective patient monitoring and development of new treatment methods.

  10. Hybrid microwave/conventionally heated calorimeter

    NASA Astrophysics Data System (ADS)

    Binner, Jon G. P.; Price, Duncan M.; Reading, Mike; Vaidhyanathan, Bala

    2005-06-01

    The design and construction of a calorimeter in which the specimen may be heated by microwave radiation and/or hot air is described. The apparatus was used to examine the effect of microwave radiation on the melting of benzil (89°C) and the solid-state phase transition of silver iodide (147°C). Reproducibility of transition temperature determinations were within ±1°C. No changes were observed for benzil but silver iodide exhibited an apparent reduction in transition temperature to around 120°C in the presence of microwaves, which increased with the level of microwave irradiation.

  11. Quantum logic gates based on coherent electron transport in quantum wires.

    PubMed

    Bertoni, A; Bordone, P; Brunetti, R; Jacoboni, C; Reggiani, S

    2000-06-19

    It is shown that the universal set of quantum logic gates can be realized using solid-state quantum bits based on coherent electron transport in quantum wires. The elementary quantum bits are realized with a proper design of two quantum wires coupled through a potential barrier. Numerical simulations show that (a) a proper design of the coupling barrier allows one to realize any one-qbit rotation and (b) Coulomb interaction between two qbits of this kind allows the implementation of the CNOT gate. These systems are based on a mature technology and seem to be integrable with conventional electronics.

  12. Site-Selective Benzannulation of N-Heterocycles in Bidentate Ligands Leads to Blue-Shifted Emission from [( P^N)Cu]2(μ-X)2 Dimers.

    PubMed

    Mondal, Rajarshi; Lozada, Issiah B; Davis, Rebecca L; Williams, J A Gareth; Herbert, David E

    2018-05-07

    Benzannulated bidentate pyridine/phosphine ( P^N) ligands bearing quinoline or phenanthridine (3,4-benzoquinoline) units have been prepared, along with their halide-bridged, dimeric Cu(I) complexes of the form [( P^N)Cu] 2 (μ-X) 2 . The copper complexes are phosphorescent in the orange-red region of the spectrum in the solid-state under ambient conditions. Structural characterization in solution and the solid-state reveals a flexible conformational landscape, with both diamond-like and butterfly motifs available to the Cu 2 X 2 cores. Comparing the photophysical properties of complexes of (quinolinyl)phosphine ligands with those of π-extended (phenanthridinyl)phosphines has revealed a counterintuitive impact of site-selective benzannulation. Contrary to conventional assumptions regarding π-extension and a bathochromic shift in the lowest energy absorption maxima, a blue shift of nearly 40 nm in the emission wavelength is observed for the complexes with larger ligand π-systems, which is assigned as phosphorescence on the basis of emission energies and lifetimes. Comparison of the ground-state and triplet excited state structures optimized from DFT and TD-DFT calculations allows attribution of this effect to a greater rigidity for the benzannulated complexes resulting in a higher energy emissive triplet state, rather than significant perturbation of orbital energies. This study reveals that ligand structure can impact photophysical properties for emissive molecules by influencing their structural rigidity, in addition to their electronic structure.

  13. Effect of proton-conduction in electrolyte on electric efficiency of multi-stage solid oxide fuel cells

    PubMed Central

    Matsuzaki, Yoshio; Tachikawa, Yuya; Somekawa, Takaaki; Hatae, Toru; Matsumoto, Hiroshige; Taniguchi, Shunsuke; Sasaki, Kazunari

    2015-01-01

    Solid oxide fuel cells (SOFCs) are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Therefore, evolved technologies are required to achieve considerably higher electrical efficiencies. Here we present an innovative concept for a critically-high fuel-to-electricity conversion efficiency of up to 85% based on the lower heating value (LHV), in which a high-temperature multi-stage electrochemical oxidation is combined with a proton-conducting solid electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 76% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC). PMID:26218470

  14. Effect of proton-conduction in electrolyte on electric efficiency of multi-stage solid oxide fuel cells.

    PubMed

    Matsuzaki, Yoshio; Tachikawa, Yuya; Somekawa, Takaaki; Hatae, Toru; Matsumoto, Hiroshige; Taniguchi, Shunsuke; Sasaki, Kazunari

    2015-07-28

    Solid oxide fuel cells (SOFCs) are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Therefore, evolved technologies are required to achieve considerably higher electrical efficiencies. Here we present an innovative concept for a critically-high fuel-to-electricity conversion efficiency of up to 85% based on the lower heating value (LHV), in which a high-temperature multi-stage electrochemical oxidation is combined with a proton-conducting solid electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 76% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC).

  15. Coordinated garbage collection for raid array of solid state disks

    DOEpatents

    Dillow, David A; Ki, Youngjae; Oral, Hakki S; Shipman, Galen M; Wang, Feiyi

    2014-04-29

    An optimized redundant array of solid state devices may include an array of one or more optimized solid-state devices and a controller coupled to the solid-state devices for managing the solid-state devices. The controller may be configured to globally coordinate the garbage collection activities of each of said optimized solid-state devices, for instance, to minimize the degraded performance time and increase the optimal performance time of the entire array of devices.

  16. Microgravity and Hypogravity Compatible Methods for the Destruction of Solid Wastes by Magnetically Assisted Gasification

    NASA Technical Reports Server (NTRS)

    Atwater, James E.; Akse, James R.; Wheeler, Richard R., Jr.; Jovanovic, Goran N.; Pinto-Espinoza, Joaquin; Reed, Brian; Sornchamni, Thana

    2003-01-01

    This report summarizes a three-year collaborative effort between researchers at UMPQUA Research Company (URC) and the Chemical Engineering Department at Oregon State University (OSU). The Magnetically Assisted Gasification (MAG) concept was originally conceived as a microgravity and hypogravity compatible means for the decomposition of solid waste materials generated aboard spacecraft, lunar and planetary habitations, and for the recovery of potentially valuable resources. While a number of methods such as supercritical water oxidation (SCW0), fluidized bed incineration, pyrolysis , composting and related biological processes have been demonstrated for the decomposition of solid wastes, none of these methods are particularly well- suited for employment under microgravity or hypogravity conditions. For example, fluidized bed incineration relies upon a balance between drag forces which the flowing gas stream exerts upon the fluidization particles and the opposing force of gravity. In the absence of gravity, conventional fluidization cannot take place. Hypogravity operation can also be problematic for conventional fluidized bed reactors, because the various factors which govern fluidization phenomena do not all scale linearly with gravity. For this reason it may be difficult to design and test fluidized bed reactors in lg, which are intended to operate under different gravitational conditions. However, fluidization can be achieved in microgravity (and hypogravity) if a suitable replacement force to counteract the forces between fluid and particles can be found. Possible alternatives include: centripetal force, electric fields, or magnetic fields. Of these, magnetic forces created by the action of magnetic fields and magnetic field gradients upon ferromagnetic media offer the most practical approach. The goal of this URC-OSU collaborative effort was to develop magnetic hardware and methods to control the degree of fluidization (or conversely consolidation) of granular ferromagnetic media and to employ these innovations in sequential filtration and fluidized bed processes for the segregation and decomposition of solid waste materials, and for the concentration and collection of inorganic residue (ash). This required the development of numerous enabling technologies and tools.

  17. Numerical Simulation of Transient Liquid Phase Bonding under Temperature Gradient

    NASA Astrophysics Data System (ADS)

    Ghobadi Bigvand, Arian

    Transient Liquid Phase bonding under Temperature Gradient (TG-TLP bonding) is a relatively new process of TLP diffusion bonding family for joining difficult-to-weld aerospace materials. Earlier studies have suggested that in contrast to the conventional TLP bonding process, liquid state diffusion drives joint solidification in TG-TLP bonding process. In the present work, a mass conservative numerical model that considers asymmetry in joint solidification is developed using finite element method to properly study the TG-TLP bonding process. The numerical results, which are experimentally verified, show that unlike what has been previously reported, solid state diffusion plays a major role in controlling the solidification behavior during TG-TLP bonding process. The newly developed model provides a vital tool for further elucidation of the TG-TLP bonding process.

  18. Novel method for determination of zinc traces in beverages and water samples by solid surface fluorescence using a conventional quartz cuvette.

    PubMed

    Talio, María Carolina; Acosta, María Gimena; Acosta, Mariano; Olsina, Roberto; Fernández, Liliana P

    2015-05-15

    A new method for zinc pre-concentration/separation and determination by molecular fluorescence is proposed. The metal was complexed with o-phenanthroline and eosin at pH 7.5 in Tris; a piece of filter paper was used as a solid support and solid fluorescent emission measured using a conventional quartz cuvette. Under optimal conditions, the limits of detection and quantification were 0.36 × 10(-3) and 1.29 × 10(-3) μg L(-1), respectively, and the linear range from 1.29 × 10(-3) to 4.50 μg L(-1). This method showed good sensitivity and selectivity, and it was applied to the determination of zinc in foods and tap water. The absence of filtration reduced the consumption of water and electricity. Additionally, the use of common filter papers makes it a simpler and more rapid alternative to conventional methods, with sensitivity and accuracy similar to atomic spectroscopies using a typical laboratory instrument. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Preparation of LaB{sub 3}O{sub 6}:Eu{sup 3+} phosphors by a facile precursor method and their luminescent properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Xia; Liang, Pan; Huang, Hong-Sheng

    2014-04-01

    Graphical abstract: LaB{sub 3}O{sub 6}:Eu{sup 3+} phosphor was obtained by calcining the precursor which was synthesized by boric acid melting method. It (a) exhibits much stronger PL intensity than that (b) prepared by conventional solid state reaction method. - Highlights: • A calcining precursor method was used for preparation of LaB{sub 3}O{sub 6}:Eu{sup 3+} phosphor. • Precursor was prepared by boric acid melting method. • The luminescence intensity of LaB{sub 3}O{sub 6}:Eu{sup 3+} was enhanced by the present method. - Abstract: The LaB{sub 3}O{sub 6}:Eu{sup 3+} phosphors were prepared by calcining the precursors which were synthesized by boric acid meltingmore » method using rare earth oxide and boric acid as raw materials, and they were characterized by EDS, XRD, IR, SEM and PL. The influences of reaction temperature for the preparation of precursor and subsequent calcination temperature and time of precursor on the luminescence properties of LaB{sub 3}O{sub 6}:Eu{sup 3+} phosphor were investigated. The results showed that the LaB{sub 3}O{sub 6}:Eu{sup 3+} phosphors with maximum luminescent intensity were obtained by calcining precursor at 1000 °C for 6 h, in which the precursor was prepared at 200 °C for 72 h. Compared with the conventional high temperature solid-state reaction method, the pure LaB{sub 3}O{sub 6}:Eu{sup 3+} phosphor can be obtained at relatively lower calcination temperature by the precursor method and exhibits much stronger emission intensity.« less

  20. Ultrashort pulsed laser ablation for decollation of solid state lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Hördemann, C.; Anand, H.; Gillner, A.

    2017-08-01

    Rechargeable lithium-ion batteries with liquid electrolytes are the main energy source for many electronic devices that we use in our everyday lives. However, one of the main drawbacks of this energy storage technology is the use of liquid electrolyte, which can be hazardous to the user as well as the environment. Moreover, lithium-ion batteries are limited in voltage, energy density and operating temperature range. One of the most novel and promising battery technologies available to overcome the above-mentioned drawbacks is the Solid-State Lithium-Ion Battery (SSLB). This battery type can be produced without limitations to the geometry and is also bendable, which is not possible with conventional batteries1 . Additionally, SSLBs are characterized by high volumetric and gravimetric energy density and are intrinsically safe since no liquid electrolyte is used2-4. Nevertheless, the manufacturing costs of these batteries are still high. The existing production-technologies are comparable to the processes used in the semiconductor industry and single cells are produced in batches with masked-deposition at low deposition rates. In order to decrease manufacturing costs and to move towards continuous production, Roll2Roll production methods are being proposed5, 6. These methods offer the possibility of producing large quantities of substrates with deposited SSLB-layers. From this coated substrate, single cells can be cut out. For the flexible decollation of SSLB-cells from the substrate, new manufacturing technologies have to be developed since blade-cutting, punching or conventional laser-cutting processes lead to short circuiting between the layers. Here, ultra-short pulsed laser ablation and cutting allows the flexible decollation of SSLBs. Through selective ablation of individual layers, an area for the cutting kerf is prepared to ensure a shortcut-free decollation.

  1. Ensemble MD simulations restrained via crystallographic data: Accurate structure leads to accurate dynamics

    PubMed Central

    Xue, Yi; Skrynnikov, Nikolai R

    2014-01-01

    Currently, the best existing molecular dynamics (MD) force fields cannot accurately reproduce the global free-energy minimum which realizes the experimental protein structure. As a result, long MD trajectories tend to drift away from the starting coordinates (e.g., crystallographic structures). To address this problem, we have devised a new simulation strategy aimed at protein crystals. An MD simulation of protein crystal is essentially an ensemble simulation involving multiple protein molecules in a crystal unit cell (or a block of unit cells). To ensure that average protein coordinates remain correct during the simulation, we introduced crystallography-based restraints into the MD protocol. Because these restraints are aimed at the ensemble-average structure, they have only minimal impact on conformational dynamics of the individual protein molecules. So long as the average structure remains reasonable, the proteins move in a native-like fashion as dictated by the original force field. To validate this approach, we have used the data from solid-state NMR spectroscopy, which is the orthogonal experimental technique uniquely sensitive to protein local dynamics. The new method has been tested on the well-established model protein, ubiquitin. The ensemble-restrained MD simulations produced lower crystallographic R factors than conventional simulations; they also led to more accurate predictions for crystallographic temperature factors, solid-state chemical shifts, and backbone order parameters. The predictions for 15N R1 relaxation rates are at least as accurate as those obtained from conventional simulations. Taken together, these results suggest that the presented trajectories may be among the most realistic protein MD simulations ever reported. In this context, the ensemble restraints based on high-resolution crystallographic data can be viewed as protein-specific empirical corrections to the standard force fields. PMID:24452989

  2. Modes of surface premelting in colloidal crystals composed of attractive particles

    NASA Astrophysics Data System (ADS)

    Li, Bo; Wang, Feng; Zhou, Di; Peng, Yi; Ni, Ran; Han, Yilong

    2016-03-01

    Crystal surfaces typically melt into a thin liquid layer at temperatures slightly below the melting point of the crystal. Such surface premelting is prevalent in all classes of solids and is important in a variety of metallurgical, geological and meteorological phenomena. Premelting has been studied using X-ray diffraction and differential scanning calorimetry, but the lack of single-particle resolution makes it hard to elucidate the underlying mechanisms. Colloids are good model systems for studying phase transitions because the thermal motions of individual micrometre-sized particles can be tracked directly using optical microscopy. Here we use colloidal spheres with tunable attractions to form equilibrium crystal-vapour interfaces, and study their surface premelting behaviour at the single-particle level. We find that monolayer colloidal crystals exhibit incomplete premelting at their perimeter, with a constant liquid-layer thickness. In contrast, two- and three-layer crystals exhibit conventional complete melting, with the thickness of the surface liquid diverging as the melting point is approached. The microstructures of the surface liquids differ in certain aspects from what would be predicted by conventional premelting theories. Incomplete premelting in the monolayer crystals is triggered by a bulk isostructural solid-solid transition and truncated by a mechanical instability that separately induces homogeneous melting within the bulk. This finding is in contrast to the conventional assumption that two-dimensional crystals melt heterogeneously from their free surfaces (that is, at the solid-vapour interface). The unexpected bulk melting that we observe for the monolayer crystals is accompanied by the formation of grain boundaries, which supports a previously proposed grain-boundary-mediated two-dimensional melting theory. The observed interplay between surface premelting, bulk melting and solid-solid transitions challenges existing theories of surface premelting and two-dimensional melting.

  3. Elucidating the Charge Transfer Mechanism in Radical Polymer Thin Films

    NASA Astrophysics Data System (ADS)

    Mukherjee, Sanjoy; Boudouris, Bryan

    The active role of polymers in organic electronics has attracted significant attention in recent decades. Beyond conventional conjugated polymers, recently radical polymers have received a great deal of consideration by the community. Radical polymers are redox-active macromolecules with non-conjugated backbones functionalized with persistent radical sites. Because of their nascent nature, many open questions regarding the physics of their solid-state charge transfer mechanism still exist. In order to address these questions, well-defined radical polymers were synthesized and blended in a manner such that there was tight control over the radical density within the conducting thin films. We demonstrate that the systematic manipulation of the radical-to-radical spacing in open-shell macromolecules leads to exponential changes in the macroscopic electrical conductivity, and temperature-independent charge transport behaviour. Thus, a clear picture emerges that charge transfer in radical polymers is dictated by a tunnelling mechanism between proximal sites. This behavior is consistent with a distinct mechanism similar to redox reactions in biological media, but is unique relative to transport in common conjugated polymers. These results constitute the first experimental insight into the mechanism of solid-state electrical conduction in radical polymers.

  4. Enhanced cycling stability of NiCo2S4@NiO core-shell nanowire arrays for all-solid-state asymmetric supercapacitors.

    PubMed

    Huang, Yuanyuan; Shi, Tielin; Jiang, Shulan; Cheng, Siyi; Tao, Xiangxu; Zhong, Yan; Liao, Guanglan; Tang, Zirong

    2016-12-07

    As a new class of pseudocapacitive material, metal sulfides possess high electrochemical performance. However, their cycling performance as conventional electrodes is rather poor for practical applications. In this article, we report an original composite electrode based on NiCo 2 S 4 @NiO core-shell nanowire arrays (NWAs) with enhanced cycling stability. This three-dimensional electrode also has a high specific capacitance of 12.2 F cm -2 at the current density of 1 mA cm -2 and excellent cycling stability (about 89% retention after 10,000 cycles). Moreover, an all-solid-state asymmetric supercapacitor (ASC) device has been assembled with NiCo 2 S 4 @NiO NWAs as the positive electrode and active carbon (AC) as the negative electrode, delivering a high energy density of 30.38 W h kg -1 at 0.288 KW kg -1 and good cycling stability (about 109% retention after 5000 cycles). The results show that NiCo 2 S 4 @NiO NWAs are promising for high-performance supercapacitors with stable cycling based on the unique core-shell structure and well-designed combinations.

  5. Enhanced cycling stability of NiCo2S4@NiO core-shell nanowire arrays for all-solid-state asymmetric supercapacitors

    NASA Astrophysics Data System (ADS)

    Huang, Yuanyuan; Shi, Tielin; Jiang, Shulan; Cheng, Siyi; Tao, Xiangxu; Zhong, Yan; Liao, Guanglan; Tang, Zirong

    2016-12-01

    As a new class of pseudocapacitive material, metal sulfides possess high electrochemical performance. However, their cycling performance as conventional electrodes is rather poor for practical applications. In this article, we report an original composite electrode based on NiCo2S4@NiO core-shell nanowire arrays (NWAs) with enhanced cycling stability. This three-dimensional electrode also has a high specific capacitance of 12.2 F cm-2 at the current density of 1 mA cm-2 and excellent cycling stability (about 89% retention after 10,000 cycles). Moreover, an all-solid-state asymmetric supercapacitor (ASC) device has been assembled with NiCo2S4@NiO NWAs as the positive electrode and active carbon (AC) as the negative electrode, delivering a high energy density of 30.38 W h kg-1 at 0.288 KW kg-1 and good cycling stability (about 109% retention after 5000 cycles). The results show that NiCo2S4@NiO NWAs are promising for high-performance supercapacitors with stable cycling based on the unique core-shell structure and well-designed combinations.

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Raj, C. Justin, E-mail: cjustinraj@gmail.com; Paramesh, G.; Prakash, B. Shri

    Highlights: • Mg doped zinc oxide ceramics were fabricated by co-precipitation/solid state reaction. • MZO ceramics shown a Debye type and colossal dielectric response. • Physical absorption of atmospheric water vapor contributes these high permittivity. • The fabricated ceramic shows Maxwell–Wagner type of relaxation. - Abstract: Zn{sub 1−x}Mg{sub x}O ( ≤ x ≤ 0.1) ceramics were fabricated by conventional solid-state reaction of co-precipitated zinc oxide and magnesium hydroxide nanoparticles. Structural and morphological properties of the fabricated ceramics were studied using X-ray diffraction and scanning electron microscopic analysis. The dielectric measurements of the ceramics were carried out as a function ofmore » frequency and temperature respectively. Interestingly, Mg doped ZnO (MZO) samples exhibited colossal dielectric response (∼1 × 10{sup 4} at 1 kHz) with Debye like relaxation. The detailed dielectric studies and thermal analyses showed that the unusual dielectric response of the samples were originated from the defected grain and grain boundary (GB) conductivity relaxations due to the absorbed atmospheric water vapor (moisture). Impedance spectroscopy was employed to determine the defected grain and GB resistances, capacitances and which supported Maxwell–Wagner type relaxation phenomena.« less

  7. Predictive modeling of solidification during laser additive manufacturing of nickel superalloys: recent developments, future directions

    NASA Astrophysics Data System (ADS)

    Ghosh, Supriyo

    2018-01-01

    Additive manufacturing (AM) processes produce parts with improved physical, chemical, and mechanical properties compared to conventional manufacturing processes. In AM processes, intricate part geometries are produced from multicomponent alloy powder, in a layer-by-layer fashion with multipass laser melting, solidification, and solid-state phase transformations, in a shorter manufacturing time, with minimal surface finishing, and at a reasonable cost. However, there is an increasing need for post-processing of the manufactured parts via, for example, stress relieving heat treatment and hot isostatic pressing to achieve homogeneous microstructure and properties at all times. Solidification in an AM process controls the size, shape, and distribution of the grains, the growth morphology, the elemental segregation and precipitation, the subsequent solid-state phase changes, and ultimately the material properties. The critical issues in this process are linked with multiphysics (such as fluid flow and diffusion of heat and mass) and multiscale (lengths, times and temperature ranges) challenges that arise due to localized rapid heating and cooling during AM processing. The alloy chemistry-process-microstructure-property-performance correlation in this process will be increasingly better understood through multiscale modeling and simulation.

  8. Enhanced cycling stability of NiCo2S4@NiO core-shell nanowire arrays for all-solid-state asymmetric supercapacitors

    PubMed Central

    Huang, Yuanyuan; Shi, Tielin; Jiang, Shulan; Cheng, Siyi; Tao, Xiangxu; Zhong, Yan; Liao, Guanglan; Tang, Zirong

    2016-01-01

    As a new class of pseudocapacitive material, metal sulfides possess high electrochemical performance. However, their cycling performance as conventional electrodes is rather poor for practical applications. In this article, we report an original composite electrode based on NiCo2S4@NiO core-shell nanowire arrays (NWAs) with enhanced cycling stability. This three-dimensional electrode also has a high specific capacitance of 12.2 F cm−2 at the current density of 1 mA cm−2 and excellent cycling stability (about 89% retention after 10,000 cycles). Moreover, an all-solid-state asymmetric supercapacitor (ASC) device has been assembled with NiCo2S4@NiO NWAs as the positive electrode and active carbon (AC) as the negative electrode, delivering a high energy density of 30.38 W h kg−1 at 0.288 KW kg−1 and good cycling stability (about 109% retention after 5000 cycles). The results show that NiCo2S4@NiO NWAs are promising for high-performance supercapacitors with stable cycling based on the unique core-shell structure and well-designed combinations. PMID:27924927

  9. Fuzzy logic control of rotating drum bioreactor for improved production of amylase and protease enzymes by Aspergillus oryzae in solid-state fermentation.

    PubMed

    Sukumprasertsri, Monton; Unrean, Pornkamol; Pimsamarn, Jindarat; Kitsubun, Panit; Tongta, Anan

    2013-03-01

    In this study, we compared the performance of two control systems, fuzzy logic control (FLC) and conventional control (CC). The control systems were applied for controlling temperature and substrate moisture content in a solidstate fermentation for the biosynthesis of amylase and protease enzymes by Aspergillus oryzae. The fermentation process was achieved in a 200 L rotating drum bioreactor. Three factors affecting temperature and moisture content in the solid-state fermentation were considered. They were inlet air velocity, speed of the rotating drum bioreactor, and spray water addition. The fuzzy logic control system was designed using four input variables: air velocity, substrate temperature, fermentation time, and rotation speed. The temperature was controlled by two variables, inlet air velocity and rotational speed of bioreactor, while the moisture content was controlled by spray water. Experimental results confirmed that the FLC system could effectively control the temperature and moisture content of substrate better than the CC system, resulting in an increased enzyme production by A. oryzae. Thus, the fuzzy logic control is a promising control system that can be applied for enhanced production of enzymes in solidstate fermentation.

  10. Solid state consolidation nanocrystalline copper-tungsten using cold spray

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hall, Aaron Christopher; Sarobol, Pylin; Argibay, Nicolas

    It is well known that nanostructured metals can exhibit significantly improved properties compared to metals with conventional grain size. Unfortunately, nanocrystalline metals typically are not thermodynamically stable and exhibit rapid grain growth at moderate temperatures. This severely limits their processing and use, making them impractical for most engineering applications. Recent work has shown that a number of thermodynamically stable nanocrystalline metal alloys exist. These alloys have been prepared as powders using severe plastic deformation (e.g. ball milling) processes. Consolidation of these powders without compromise of their nanocrystalline microstructure is a critical step to enabling their use as engineering materials. Wemore » demonstrate solid-state consolidation of ball milled copper-tantalum nanocrystalline metal powder using cold spray. Unfortunately, the nanocrystalline copper-tantalum powder that was consolidated did not contain the thermodynamically stable copper-tantalum nanostructure. Nevertheless, this does this demonstrates a pathway to preparation of bulk thermodynamically stable nanocrystalline copper-tantalum. Furthermore, it demonstrates a pathway to additive manufacturing (3D printing) of nanocrystalline copper-tantalum. Additive manufacturing of thermodynamically stable nanocrystalline metals is attractive because it enables maximum flexibility and efficiency in the use of these unique materials.« less

  11. A flexible Li-ion battery with design towards electrodes electrical insulation

    NASA Astrophysics Data System (ADS)

    Vieira, E. M. F.; Ribeiro, J. F.; Sousa, R.; Correia, J. H.; Goncalves, L. M.

    2016-08-01

    The application of micro electromechanical systems (MEMS) technology in several consumer electronics leads to the development of micro/nano power sources with high power and MEMS integration possibility. This work presents the fabrication of a flexible solid-state Li-ion battery (LIB) (~2.1 μm thick) with a design towards electrodes electrical insulation, using conventional, low cost and compatible MEMS fabrication processes. Kapton® substrate provides flexibility to the battery. E-beam deposited 300 nm thick Ge anode was coupled with LiCoO2/LiPON (cathode/solid-state electrolyte) in a battery system. LiCoO2 and LiPON films were deposited by RF-sputtering with a power source of 120 W and 100 W, respectively. LiCoO2 film was annealed at 400 °C after deposition. The new design includes Si3N4 and LiPO thin-films, providing electrode electrical insulation and a battery chemical stability safeguard, respectively. Microstructure and battery performance were investigated by scanning electron microscopy, electric resistivity and electrochemical measurements (open circuit potential, charge/discharge cycles and electrochemical impedance spectroscopy). A rechargeable thin-film and lightweight flexible LIB using MEMS processing compatible materials and techniques is reported.

  12. Traceable measurements of the electrical parameters of solid-state lighting products

    NASA Astrophysics Data System (ADS)

    Zhao, D.; Rietveld, G.; Braun, J.-P.; Overney, F.; Lippert, T.; Christensen, A.

    2016-12-01

    In order to perform traceable measurements of the electrical parameters of solid-state lighting (SSL) products, it is necessary to technically adequately define the measurement procedures and to identify the relevant uncertainty sources. The present published written standard for SSL products specifies test conditions, but it lacks an explanation of how adequate these test conditions are. More specifically, both an identification of uncertainty sources and a quantitative uncertainty analysis are absent. This paper fills the related gap in the present written standard. New uncertainty sources with respect to conventional lighting sources are determined and their effects are quantified. It shows that for power measurements, the main uncertainty sources are temperature deviation, power supply voltage distortion, and instability of the SSL product. For current RMS measurements, the influence of bandwidth, shunt resistor, power supply source impedance and ac frequency flatness are significant as well. The measurement uncertainty depends not only on the test equipment but is also a function of the characteristics of the device under test (DUT), for example, current harmonics spectrum and input impedance. Therefore, an online calculation tool is provided to help non-electrical experts. Following our procedures, unrealistic uncertainty estimations, unnecessary procedures and expensive equipment can be prevented.

  13. Skin photoprotection improvement: synergistic interaction between lipid nanoparticles and organic UV filters.

    PubMed

    Nikolić, S; Keck, C M; Anselmi, C; Müller, R H

    2011-07-29

    A photoprotective formulation was developed with an increased sunprotection factor (SPF), compared to a conventional nanoemulsion, but having the same concentration of three molecular sunscreens, namely ethylhexyl triazone, bis-ethylhexyloxyphenol methoxyphenyl triazine, and ethylhexyl methoxycinnamate. The sunscreen mixture was incorporated into nanostructured lipid carriers (NLCs). The ability of nine different solid lipids to yield stable aqueous NLC suspensions was assessed. After the production by hot high pressure homogenization, the NLC were analyzed in terms of particle size, physical state, particle shape, ultraviolet absorbance and stability. The particle size for all NLC was around 200 nm after production. The NLC suspension with carnauba wax had superior UV absorbance, NLC from bees wax showed similar efficiency as the reference emulsion. The NLC formulations were incorporated into hydrogel formulations and the in vitro SPF was measured. This study demonstrated that approximately 45% higher SPF values could be obtained when the organic UV filters were incorporated into carnauba wax NLC, in comparison to the reference nanoemulsion and bees wax NLC. The data showed that the synergistic effect of NLC and incorporated sunscreens depends not only on the solid state of the lipid but also on its type. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. A novel optical gating method for laser gated imaging

    NASA Astrophysics Data System (ADS)

    Ginat, Ran; Schneider, Ron; Zohar, Eyal; Nesher, Ofer

    2013-06-01

    For the past 15 years, Elbit Systems is developing time-resolved active laser-gated imaging (LGI) systems for various applications. Traditional LGI systems are based on high sensitive gated sensors, synchronized to pulsed laser sources. Elbit propriety multi-pulse per frame method, which is being implemented in LGI systems, improves significantly the imaging quality. A significant characteristic of the LGI is its ability to penetrate a disturbing media, such as rain, haze and some fog types. Current LGI systems are based on image intensifier (II) sensors, limiting the system in spectral response, image quality, reliability and cost. A novel propriety optical gating module was developed in Elbit, untying the dependency of LGI system on II. The optical gating module is not bounded to the radiance wavelength and positioned between the system optics and the sensor. This optical gating method supports the use of conventional solid state sensors. By selecting the appropriate solid state sensor, the new LGI systems can operate at any desired wavelength. In this paper we present the new gating method characteristics, performance and its advantages over the II gating method. The use of the gated imaging systems is described in a variety of applications, including results from latest field experiments.

  15. Beating the Heat: Fast Scanning Melts Beta Sheet Crystals

    NASA Astrophysics Data System (ADS)

    Cebe, Peggy; Hu, Xiao; Kaplan, David; Zhuravlev, Evgeny; Wurm, Andreas; Arbeiter, Daniella; Schick, Christoph

    2014-03-01

    Beta-pleated-sheet crystals are among the most stable of protein secondary structures, and are responsible for the remarkable physical properties of many fibrous proteins, such as silk. Previous thinking was that beta-pleated-sheet crystals in the dry solid state would not melt upon input of heat energy alone. Indeed, at conventional heating rates (~1-50 °C/min), silk exhibits its glass transition (~175 °C), followed by cold crystallization, and then by immediate thermal degradation beginning at about 225 °C. Here we demonstrate that beta-pleated-sheet crystals can melt directly from the solid state to become random coils, helices, and turns. We use fast scanning chip calorimetry at 2,000 K/s to avoid thermal degradation, and report the first reversible thermal melting of protein beta-pleated-sheet crystals, exemplified by silk fibroin. The similarity between thermal melting behavior of lamellar crystals of synthetic polymers and beta-pleated-sheet crystals is confirmed. The authors acknowledge support from the National Science Foundation and German Academic Exchange Service DAAD; EZ acknowledges a European Union funded Marie Curie EST fellowship (ADVATEC); XH and DK acknowledge NIH P41 Tissue Engineering Resource Center.

  16. Aircraft Propeller Hub Repair

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muth, Thomas R.; Peter, William H.

    The team performed a literature review, conducted residual stress measurements, performed failure analysis, and demonstrated a solid state additive manufacturing repair technique on samples removed from a scrapped propeller hub. The team evaluated multiple options for hub repair that included existing metal buildup technologies that the Federal Aviation Administration (FAA) has already embraced, such as cold spray, high velocity oxy-fuel deposition (HVOF), and plasma spray. In addition the team helped Piedmont Propulsion Systems, LLC (PPS) evaluate three potential solutions that could be deployed at different stages in the life cycle of aluminum alloy hubs, in addition to the conventional spraymore » coating method for repair. For new hubs, a machining practice to prevent fretting with the steel drive shaft was recommended. For hubs that were refurbished with some material remaining above the minimal material condition (MMC), a silver interface applied by an electromagnetic pulse additive manufacturing method was recommended. For hubs that were at or below the MMC, a solid state additive manufacturing technique using ultrasonic welding (UW) of thin layers of 7075 aluminum to the hub interface was recommended. A cladding demonstration using the UW technique achieved mechanical bonding of the layers showing promise as a viable repair method.« less

  17. Potassium ferrate treatment of RFETS` contaminated groundwater

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1995-01-01

    The potassium ferrate treatment study of Rocky Flats Environmental Technology Site (RFETS) groundwater was performed under the Sitewide Treatability Studies Program (STSP). This study was undertaken to determine the effectiveness of potassium ferrate in a water treatment system to remove the contaminants of concern (COCS) from groundwater at the RFETS. Potassium ferrate is a simple salt where the iron is in the plus six valence state. It is the iron at the plus six valence state (Fe {sup +6}) that makes it an unique water treatment chemical, especially in waters where the pH is greater than seven. In basic solutionsmore » where the solubility of the oxides/hydroxides of many of the COCs is low, solids are formed as the pH is raised. By using ferrate these solids are agglomerated so they can be effectively removed by sedimentation in conventional water treatment equipment. The objective of this study was to determine the quality of water after treatment with potassium ferrate and to determine if the Colorado Water Quality Control Commission (CWQCC) discharge limits for the COCs listed in Table 1.0-1 could be met. Radionuclides in the groundwater were of special concern.« less

  18. Laboratory Production of Lemon Liqueur (Limoncello) by Conventional Maceration and a Two-Syringe System to Illustrate Rapid Solid-Liquid Dynamic Extraction

    ERIC Educational Resources Information Center

    Naviglio, Daniele; Montesano, Domenico; Gallo, Monica

    2015-01-01

    Two experimental techniques of solid-liquid extraction are compared relating to the lab-scale production of lemon liqueur, most commonly named "limoncello"; the first is the official method of maceration for the solid-liquid extraction of analytes and is widely used to extract active ingredients from a great variety of natural products;…

  19. Enhanced oral bioavailability of felodipine by novel solid self-microemulsifying tablets.

    PubMed

    Jing, Boyu; Wang, Zhiyuan; Yang, Rui; Zheng, Xia; Zhao, Jia; Tang, Si; He, Zhonggui

    2016-01-01

    The novel self-microemulsifying (SME) tablets were developed to enhance the oral bioavailability of a poor water-soluble drug felodipine (FDP). Firstly, FDP was dissolved in the optimized liquid self-microemusifying drug delivery systems (SMEDDS) containing Miglyol® 812, Cremophor® RH 40, Tween 80 and Transcutol® P, and the mixture was solidified with porous silicon dioxide and crospovidone as adsorbents. Then after combining the solidified powders with other excipients, the solid SME tablets were prepared by wet granulation-compression method. The prepared tablets possessed satisfactory characterization; the droplet size of the SME tablets following self-emulsification in water was nearly equivalent to the liquid SMEDDS (68.4 ± 14.0 and 64.4 ± 12.0 nm); differential scanning calorimetry (DSC) and powder X-ray diffractometry (PXRD) analysis demonstrated that FDP in SME tablets had undergone a polymorphism transition from a crystal form to an amorphous state, which was further confirmed by transmission electron microscopy (TEM). A similar dissolution performance of SME tablets and liquid SMEDDS was also obtained under the sink condition (85% within 10 min), both significantly higher than commercial tablets. The oral bioavailability was evaluated for the SME tablets, liquid SMEDDS and commercial conventional tablets in the fasted beagle dogs. The AUC of FDP from the SME tablets was about 2-fold greater than that of conventional tablets, but no significant difference was found when compared with the liquid SMEDDS. Accordingly, these preliminary results suggest that this formulation approach offers a useful large-scale producing method to prepare the solid SME tablets from the liquid SMEDDS for oral bioavailability equivalent enhancement of poorly soluble FDP.

  20. The equation of state of 5-nitro-2,4-dihydro-1,2,4,-triazol-3-one determined via in-situ optical microscopy and interferometry measurements

    DOE PAGES

    Stavrou, Elissaios; Zaug, Joseph M.; Bastea, Sorin; ...

    2016-04-07

    Quasi-hydrostatic high-pressure equations of state (EOS) are typically determined, for crystalline solids, by measuring unit-cell volumes using x-ray diffraction (XRD) techniques. However, when characterizing low-symmetry materials with large unit cells, conventional XRD approaches may become problematic. To overcome this issue, we examined the utility of a "direct" approach toward determining high pressure material volume by measuring surface area and sample thickness using optical microscopy and interferometry (OMI) respectively. We have validated this experimental approach by comparing results obtained for TATB (2,4,6-triamino-1,3,5-trinitrobenzene) with an EOS determined from synchrotron XRD measurements; and, a good match is observed. We have measured the highmore » pressure EOS of 5-nitro-2,4-dihydro-1,2,4-triazol-3-one (α-NTO) up to 33 GPa. No high-pressure XRD EOS data have been published on α-NTO, probably due to its complex crystal structure. Furthermore, the results of this study suggest that OMI is a reliable and versatile alternative for determining EOSs, especially when conventional methodologies are impractical.« less

  1. High-precision Non-Contact Measurement of Creep of Ultra-High Temperature Materials for Aerospace

    NASA Technical Reports Server (NTRS)

    Rogers, Jan R.; Hyers, Robert

    2008-01-01

    For high-temperature applications (greater than 2,000 C) such as solid rocket motors, hypersonic aircraft, nuclear electric/thermal propulsion for spacecraft, and more efficient jet engines, creep becomes one of the most important design factors to be considered. Conventional creep-testing methods, where the specimen and test apparatus are in contact with each other, are limited to temperatures approximately 1,700 C. Development of alloys for higher-temperature applications is limited by the availability of testing methods at temperatures above 2000 C. Development of alloys for applications requiring a long service life at temperatures as low as 1500 C, such as the next generation of jet turbine superalloys, is limited by the difficulty of accelerated testing at temperatures above 1700 C. For these reasons, a new, non-contact creep-measurement technique is needed for higher temperature applications. A new non-contact method for creep measurements of ultra-high-temperature metals and ceramics has been developed and validated. Using the electrostatic levitation (ESL) facility at NASA Marshall Space Flight Center, a spherical sample is rotated quickly enough to cause creep deformation due to centrifugal acceleration. Very accurate measurement of the deformed shape through digital image analysis allows the stress exponent n to be determined very precisely from a single test, rather than from numerous conventional tests. Validation tests on single-crystal niobium spheres showed excellent agreement with conventional tests at 1985 C; however the non-contact method provides much greater precision while using only about 40 milligrams of material. This method is being applied to materials including metals and ceramics for non-eroding throats in solid rockets and next-generation superalloys for turbine engines. Recent advances in the method and the current state of these new measurements will be presented.

  2. Analysis of International Space Station Materials on MISSE-3 and MISSE-4

    NASA Technical Reports Server (NTRS)

    Finckenor, Miria M.; Golden, Johnny L.; O'Rourke, Mary Jane

    2008-01-01

    For high-temperature applications (> 2,000 C) such as solid rocket motors, hypersonic aircraft, nuclear electric/thermal propulsion for spacecraft, and more efficient jet engines, creep becomes one of the most important design factors to be considered. Conventional creep-testing methods, where the specimen and test apparatus are in contact with each other, are limited to temperatures 1,700 deg. C. Development of alloys for higher-temperature applications is limited by the availability of testing methods at temperatures above 2000 C. Development of alloys for applications requiring a long service life at temperatures as low as 1500 C, such as the next generation of jet turbine superalloys, is limited by the difficulty of accelerated testing at temperatures above 1700 0c. For these reasons, a new, non-contact creep-measurement technique is needed for higher temperature applications. A new non-contact method for creep measurements of ultra-high-temperature metals and ceramics has been developed and validated. Using the electrostatic levitation (ESL) facility at NASA Marshall Space Flight Center, a spherical sample is rotated quickly enough to cause creep deformation due to centrifugal acceleration. Very accurate measurement of the deformed shape through digital image analysis allows the stress exponent n to be determined very precisely from a single test, rather than from numerous conventional tests. Validation tests on single-crystal niobium spheres showed excellent agreement with conventional tests at 1985 C; however the non-contact method provides much greater precision while using only about 40 milligrams of material. This method is being applied to materials including metals and ceramics for noneroding throats in solid rockets and next-generation superalloys for turbine engines. Recent advances in the method and the current state of these new measurements will be presented.

  3. Rapid Solid-Liquid Dynamic Extraction (RSLDE): a New Rapid and Greener Method for Extracting Two Steviol Glycosides (Stevioside and Rebaudioside A) from Stevia Leaves.

    PubMed

    Gallo, Monica; Vitulano, Manuela; Andolfi, Anna; DellaGreca, Marina; Conte, Esterina; Ciaravolo, Martina; Naviglio, Daniele

    2017-06-01

    Stevioside and rebaudioside A are the main diterpene glycosides present in the leaves of the Stevia rebaudiana plant, which is used in the production of foods and low-calorie beverages. The difficulties associated with their extraction and purification are currently a problem for the food processing industries. The objective of this study was to develop an effective and economically viable method to obtain a high-quality product while trying to overcome the disadvantages derived from the conventional transformation processes. For this reason, extractions were carried out using a conventional maceration (CM) and a cyclically pressurized extraction known as rapid solid-liquid dynamic extraction (RSLDE) by the Naviglio extractor (NE). After only 20 min of extraction using the NE, a quantity of rebaudioside A and stevioside equal to 1197.8 and 413.6 mg/L was obtained, respectively, while for the CM, the optimum time was 90 min. From the results, it can be stated that the extraction process by NE and its subsequent purification developed in this study is a simple, economical, environmentally friendly method for producing steviol glycosides. Therefore, this method constitutes a valid alternative to conventional extraction by reducing the extraction time and the consumption of toxic solvents and favouring the use of the extracted metabolites as food additives and/or nutraceuticals. As an added value and of local interest, the experiment was carried out on stevia leaves from the Benevento area (Italy), where a high content of rebaudioside A was observed, which exhibits a sweet taste compared to stevioside, which has a significant bitter aftertaste.

  4. Removal of strontium from drinking water by conventional treatment and lime softening in bench-scale studies.

    PubMed

    O'Donnell, Alissa J; Lytle, Darren A; Harmon, Stephen; Vu, Kevin; Chait, Hannah; Dionysiou, Dionysios D

    2016-10-15

    The United States Environmental Protection Agency Contaminant Candidate List 3 lists strontium as a contaminant for potential regulatory consideration in drinking water. Very limited data is available on strontium removal from drinking water and as a result, there is an immediate need for treatment information. The objective of this work is to evaluate the effectiveness of coagulation/filtration and lime-soda ash softening treatment methods to remove strontium from surface and ground waters. Coagulation/filtration jar test results on natural waters showed that conventional treatment with aluminum and iron coagulants were able to achieve only 12% and 5.9% strontium removal, while lime softening removed as high as 78% from natural strontium-containing ground water. Controlled batch experiments on synthetic water showed that strontium removal during the lime-soda ash softening was affected by pH, calcium concentration and dissolved inorganic carbon concentration. In all softening jar tests, the final strontium concentration was directly related to the initial strontium concentration and the removal of strontium was directly associated with calcium removal. Precipitated solids showed well-formed crystals or agglomerates of mixed solids, two polymorphs of calcium carbonate (vaterite and calcite), and strontianite, depending on initial water quality conditions. X-ray diffraction analysis suggested that strontium was likely incorporated in the calcium carbonate crystal lattice and was likely responsible for removal during lime softening. Copyright © 2016. Published by Elsevier Ltd.

  5. Vortex Matter in Highly Strained Nb_{75}Zr_{25}: Analogy with Viscous Flow of Disordered Solids

    NASA Astrophysics Data System (ADS)

    Chandra, Jagdish; Manekar, Meghmalhar; Sharma, V. K.; Mondal, Puspen; Tiwari, Pragya; Roy, S. B.

    2017-01-01

    We present the results of magnetization and magneto-transport measurements in the superconducting state of an as-cast Nb_{75}Zr_{25} alloy. We also report the microstructure of our sample at various length scales by using optical, scanning electron and transmission electron microscopies. The information of microstructure is used to understand the flux pinning properties in the superconducting state within the framework of collective pinning. The magneto-transport measurements show a non-Arrhenius behaviour of the temperature- and field-dependent resistivity across the resistive transition and is understood in terms of a model for viscous flow of disordered solids which is popularly known as the `shoving model'. The activation energy for flux flow is assumed to be mainly the elastic energy stored in the flux-line lattice. The scaling of pinning force density indicates the presence of two pinning mechanisms of different origins. The elastic constants of the flux-line lattice are used to estimate the length scale of vortex lattice movement, or the volume displaced by the flux-line lattice. It appears that the vortex lattice displacement estimated from elastic energy considerations is of the same order of magnitude as that of the flux bundle hopping length during flux flow. Our results could provide possible directions for establishing a framework where vortex matter and glass-forming liquids or amorphous solids can be treated in a similar manner for understanding the phenomenon of viscous flow in disordered solids or more generally the pinning and depinning properties of elastic manifolds in random media. It is likely that the vortex molasses scenario is more suited to explain the vortex dynamics in conventional low-T_C superconductors.

  6. Conventional and microwave pyrolysis of a macroalgae waste from the Agar-Agar industry. Prospects for bio-fuel production.

    PubMed

    Ferrera-Lorenzo, N; Fuente, E; Bermúdez, J M; Suárez-Ruiz, I; Ruiz, B

    2014-01-01

    A comparative study of the pyrolysis of a macroalgae industrial solid waste (algae meal) in an electrical conventional furnace and in a microwave furnace has been carried out. It was found that the chars obtained from both pyrolyses are similar and show good properties for performing as a solid bio-fuel and as a precursor of activated carbon. Bio-oils from conventional pyrolysis have a greater number of phenolic, pyrrole and alkane compounds whereas benzene and pyridine compounds are more predominant in microwave pyrolysis with a major presence of light compounds. The bio-gas fraction from microwave pyrolysis presents a much higher syngas content (H2+CO), and a lower CO2 and CH4 proportion than that obtained by conventional pyrolysis. Yields are similar for both treatments with a slightly higher gas yield in the case of microwave pyrolysis due to the fact that microwave heating favors heterogeneous reactions between the gases and the char. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Ceramic Electrolyte Membrane Technology: Enabling Revolutionary Electrochemical Energy Storage

    DTIC Science & Technology

    2015-10-05

    ion batteries . Solid-state Li- ion batteries could significantly improve safety and eliminate the need for complex...advancing ceramic electrolyte technology for use in solid-state Li- ion batteries . Solid-state Li- ion batteries could significantly improve safety and...technology for use in solid-state Li- ion batteries and high specific energy Li-S and Li- air batteries . Solid-state Li- ion batteries could

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Du Hongliang; Zhou Wancheng; Luo Fa

    The (1-x)(K{sub 0.5}Na{sub 0.5})NbO{sub 3}-x(Ba{sub 0.5}Sr{sub 0.5})TiO{sub 3} (KNN-BST) solid solution has been synthesized by conventional solid-state sintering in order to search for the new lead-free relaxor ferroelectrics for high temperature applications. The phase structure, dielectric properties, and relaxor behavior of the (1-x)KNN-xBST solid solution are systematically investigated. The phase structure of the (1-x)KNN-xBST solid solution gradually changes from pure perovskite phase with an orthorhombic symmetry to the tetragonal symmetry, then to the pseudocubic phase, and to the cubic phase with increasing addition of BST. The 0.90KNN-0.10BST solid solution shows a broad dielectric peak with permittivity maximum near 2500 andmore » low dielectric loss (<4%) in the temperature range of 100-250 deg. C. The result indicates that this material may have great potential for a variety of high temperature applications. The diffuse phase transition and the temperature of the maximum dielectric permittivity shifting toward higher temperature with increasing frequency, which are two typical characteristics for relaxor ferroelectrics, are observed in the (1-x)KNN-xBST solid solution. The dielectric relaxor behavior obeys a modified Curie-Weiss law and a Vogel-Fulcher relationship. The relaxor nature is attributed to the appearance of polar nanoregions owing to the formation of randon fields including local electric fields and elastic fields. These results confirm that the KNN-based relaxor ferroelectrics can be regarded as an alternative direction for the development of high temperature lead-free relaxor ferroelectrics.« less

  9. Enhanced solid-state citric acid bio-production using apple pomace waste through surface response methodology.

    PubMed

    Dhillon, G S; Brar, S K; Verma, M; Tyagi, R D

    2011-04-01

      To evaluate the potential of apple pomace (AP) supplemented with rice husk for hyper citric acid production through solid-state fermentation by Aspergillus niger NRRL-567. Optimization of two key parameters, such as moisture content and inducer (ethanol and methanol) concentration was carried out by response surface methodology.   In this study, the effect of two crucial process parameters for solid-state citric acid fermentation by A. niger using AP waste supplemented with rice husk were thoroughly investigated in Erlenmeyer flasks through response surface methodology. Moisture and methanol had significant positive effect on citric acid production by A. niger grown on AP (P < 0·05). Higher values of citric acid on AP by A. niger (342·41gkg(-1) and 248·42gkg(-1) dry substrate) were obtained with 75% (v/w) moisture along with two inducers [3% (v/w) methanol and 3% (v/w) ethanol] with fermentation efficiency of 93·90% and 66·42%, respectively depending upon the total carbon utilized after 144h of incubation period. With the same optimized parameters, conventional tray fermentation was conducted. The citric acid concentration of 187·96gkg(-1) dry substrate with 3% (v/w) ethanol and 303·34gkg(-1) dry substrate with 3% (v/w) methanol were achieved representing fermentation efficiency of 50·80% and 82·89% in tray fermentation depending upon carbon utilization after 120h of incubation period.   Apple pomace proved to be the promising substrate for the hyper production of citric acid through solid-state tray fermentation, which is an economical technique and does not require any sophisticated instrumentation.   The study established that the utilization of agro-industrial wastes have positive repercussions on the economy and will help to meet the increasing demands of citric acid and moreover will help to alleviate the environmental problems resulting from the disposal of agro-industrial wastes. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  10. Bulk-Type All-Solid-State Lithium-Ion Batteries: Remarkable Performances of a Carbon Nanofiber-Supported MgH2 Composite Electrode.

    PubMed

    Zeng, Liang; Ichikawa, Takayuki; Kawahito, Koji; Miyaoka, Hiroki; Kojima, Yoshitsugu

    2017-01-25

    Magnesium hydride, MgH 2 , a recently developed compound for lithium-ion batteries, is considered to be a promising conversion-type negative electrode material due to its high theoretical lithium storage capacity of over 2000 mA h g -1 , suitable working potential, and relatively small volume expansion. Nevertheless, it suffers from unsatisfactory cyclability, poor reversibility, and slow kinetics in conventional nonaqueous electrolyte systems, which greatly limit the practical application of MgH 2 . In this work, a vapor-grown carbon nanofiber was used to enhance the electrical conductivity of MgH 2 using LiBH 4 as the solid-state electrolyte. It shows that a reversible capacity of over 1200 mA h g -1 with an average voltage of 0.5 V (vs Li/Li + ) can be obtained after 50 cycles at a current density of 1000 mA g -1 . In addition, the capacity of MgH 2 retains over 1100 mA h g -1 at a high current density of 8000 mA g -1 , which indicates the possibility of using MgH 2 as a negative electrode material for high power and high capacity lithium-ion batteries in future practical applications. Moreover, the widely studied sulfide-based solid electrolyte was also used to assemble battery cells with MgH 2 electrode in the same system, and the electrochemical performance was as good as that using LiBH 4 electrolyte.

  11. General survey of solid-waste management

    NASA Technical Reports Server (NTRS)

    Reese, T. G.; Wadle, R. C.

    1974-01-01

    Potential ways of providing solid-waste management for a building complex serviced by a modular integrated utility system (MIUS) were explored. Literature surveys were conducted to investigate both conventional and unusual systems to serve this purpose. The advantages and disadvantages of the systems most compatible with MIUS are discussed.

  12. From laser particle acceleration to the synthesis of extremely neutron rich isotopes via the novel fission-fusion mechanism

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thirolf, P. G., E-mail: Peter.Thirolf@lmu.de

    2015-02-24

    High-power, short pulse lasers have emerged in the last decade as attractive tools for accelerating charged particles (electrons, ions) to high energies over mm-scale acceleration lengths, thus promising to rival conventional acceleration techniques in the years ahead. In the first part of the article, the principles of laser-plasma interaction as well as the techniques and the current status of the acceleration of electron and ion beams will be briefly introduced. In particular with the upcoming next generation of multi-PW class laser systems, such as the one under construction for the ELI-Nuclear Physics project in Bucharest (ELI-NP), very efficient acceleration mechanismsmore » for brilliant ion beams like radiation pressure acceleration (RPA) come into reach. Here, ultra-dense ion beams reaching solid-state density can be accelerated from thin target foils, exceeding the density of conventionally accelerated ion beams by about 14 orders of magnitude. This unique property of laser-accelerated ion beams can be exploited to explore the scenario of a new reaction mechanism called ‘fission-fusion’, which will be introduced in the second part of the article. Accelerating fissile species (e.g. {sup 232}Th) towards a second layer of the same material will lead to fission both of the beam-like and target-like particles. Due to the close to solid-state density of the accelerated ion bunches, fusion may occur between neutron-rich (light) fission products. This may open an access path towards extremely neutron-rich nuclides in the vicinity of the N=126 waiting point of the astrophysical r process. ‘Waiting points’ at closed nucleon shells play a crucial role in controlling the reaction rates. However, since most of the pathway of heavy-element formation via the rapid-neutron capture process (r-process) runs in ‘terra incognita’ of the nuclear landscape, in particular the waiting point at N=126 is yet unexplored and will remain largely inaccessible to conventional nuclear reaction schemes even at next-generation radioactive beam facilities, underlining the attractive perspectives offered, e.g., by ELI-NP.« less

  13. Improved Design of Anaerobic Digesters for Household Biogas Production in Indonesia: One Cow, One Digester, and One Hour of Cooking per Day

    PubMed Central

    Usack, Joseph G.; Wiratni, Wiratni; Angenent, Largus T.

    2014-01-01

    A government-sponsored initiative in Indonesia to design and implement low-cost anaerobic digestion systems resulted in 21 full-scale systems with the aim to satisfy the cooking fuel demands of rural households owning at least one cow. The full-scale design consisted of a 0.3 m diameter PVC pipe, which was operated as a conventional plug-flow system. The system generated enough methane to power a cooking stove for ∼1 h. However, eventual clogging from solids accumulation inside the bioreactor proved to be a major drawback. Here, we improved the digester configuration to remedy clogging while maintaining system performance. Controlled experiments were performed using four 9-L laboratory-scale digesters operated at a temperature of 27 ± 1°C, a volatile solids loading rate of 2.0 g VS·L−1 ·day−1, and a 21-day hydraulic retention time. Two of the digesters were replicates of the original design (control digesters), while the other two digesters included internal mixing or effluent recycle (experimental digesters). The performance of each digester was compared based on methane yields, VS removal efficiencies, and steady-state solids concentrations during an operating period of 311 days. Statistical analyses revealed that internal mixing and effluent recycling resulted in reduced solids accumulation compared to the controls without diminishing methane yields or solids removal efficiencies. PMID:24715809

  14. Characterization of the Vibrio cholerae extracellular matrix: a top-down solid-state NMR approach.

    PubMed

    Reichhardt, Courtney; Fong, Jiunn C N; Yildiz, Fitnat; Cegelski, Lynette

    2015-01-01

    Bacterial biofilms are communities of bacterial cells surrounded by a self-secreted extracellular matrix. Biofilm formation by Vibrio cholerae, the human pathogen responsible for cholera, contributes to its environmental survival and infectivity. Important genetic and molecular requirements have been identified for V. cholerae biofilm formation, yet a compositional accounting of these parts in the intact biofilm or extracellular matrix has not been described. As insoluble and non-crystalline assemblies, determinations of biofilm composition pose a challenge to conventional biochemical and biophysical analyses. The V. cholerae extracellular matrix composition is particularly complex with several proteins, complex polysaccharides, and other biomolecules having been identified as matrix parts. We developed a new top-down solid-state NMR approach to spectroscopically assign and quantify the carbon pools of the intact V. cholerae extracellular matrix using ¹³C CPMAS and ¹³C{(¹⁵N}, ¹⁵N{³¹P}, and ¹³C{³¹P}REDOR. General sugar, lipid, and amino acid pools were first profiled and then further annotated and quantified as specific carbon types, including carbonyls, amides, glycyl carbons, and anomerics. In addition, ¹⁵N profiling revealed a large amine pool relative to amide contributions, reflecting the prevalence of molecular modifications with free amine groups. Our top-down approach could be implemented immediately to examine the extracellular matrix from mutant strains that might alter polysaccharide production or lipid release beyond the cell surface; or to monitor changes that may accompany environmental variations and stressors such as altered nutrient composition, oxidative stress or antibiotics. More generally, our analysis has demonstrated that solid-state NMR is a valuable tool to characterize complex biofilm systems. Copyright © 2014. Published by Elsevier B.V.

  15. Multiple acquisition of magic angle spinning solid-state NMR experiments using one receiver: Application to microcrystalline and membrane protein preparations

    NASA Astrophysics Data System (ADS)

    Gopinath, T.; Veglia, Gianluigi

    2015-04-01

    Solid-state NMR spectroscopy of proteins is a notoriously low-throughput technique. Relatively low-sensitivity and poor resolution of protein samples require long acquisition times for multidimensional NMR experiments. To speed up data acquisition, we developed a family of experiments called Polarization Optimized Experiments (POE), in which we utilized the orphan spin operators that are discarded in classical multidimensional NMR experiments, recovering them to allow simultaneous acquisition of multiple 2D and 3D experiments, all while using conventional probes with spectrometers equipped with one receiver. POE allow the concatenation of multiple 2D or 3D pulse sequences into a single experiment, thus potentially combining all of the aforementioned advances, boosting the capability of ssNMR spectrometers at least two-fold without the addition of any hardware. In this perspective, we describe the first generation of POE, such as dual acquisition MAS (or DUMAS) methods, and then illustrate the evolution of these experiments into MEIOSIS, a method that enables the simultaneous acquisition of multiple 2D and 3D spectra. Using these new pulse schemes for the solid-state NMR investigation of biopolymers makes it possible to obtain sequential resonance assignments, as well as distance restraints, in about half the experimental time. While designed for acquisition of heteronuclei, these new experiments can be easily implemented for proton detection and coupled with other recent advancements, such as dynamic nuclear polarization (DNP), to improve signal to noise. Finally, we illustrate the application of these methods to microcrystalline protein preparations as well as single and multi-span membrane proteins reconstituted in lipid membranes.

  16. Multiple acquisition of magic angle spinning solid-state NMR experiments using one receiver: application to microcrystalline and membrane protein preparations.

    PubMed

    Gopinath, T; Veglia, Gianluigi

    2015-04-01

    Solid-state NMR spectroscopy of proteins is a notoriously low-throughput technique. Relatively low-sensitivity and poor resolution of protein samples require long acquisition times for multidimensional NMR experiments. To speed up data acquisition, we developed a family of experiments called Polarization Optimized Experiments (POE), in which we utilized the orphan spin operators that are discarded in classical multidimensional NMR experiments, recovering them to allow simultaneous acquisition of multiple 2D and 3D experiments, all while using conventional probes with spectrometers equipped with one receiver. POE allow the concatenation of multiple 2D or 3D pulse sequences into a single experiment, thus potentially combining all of the aforementioned advances, boosting the capability of ssNMR spectrometers at least two-fold without the addition of any hardware. In this perspective, we describe the first generation of POE, such as dual acquisition MAS (or DUMAS) methods, and then illustrate the evolution of these experiments into MEIOSIS, a method that enables the simultaneous acquisition of multiple 2D and 3D spectra. Using these new pulse schemes for the solid-state NMR investigation of biopolymers makes it possible to obtain sequential resonance assignments, as well as distance restraints, in about half the experimental time. While designed for acquisition of heteronuclei, these new experiments can be easily implemented for proton detection and coupled with other recent advancements, such as dynamic nuclear polarization (DNP), to improve signal to noise. Finally, we illustrate the application of these methods to microcrystalline protein preparations as well as single and multi-span membrane proteins reconstituted in lipid membranes. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Multiple Acquisition of Magic Angle Spinning Solid-State NMR Experiments Using One Receiver: Application to Microcrystalline and Membrane Protein Preparations

    PubMed Central

    Gopinath, T.; Veglia, Gianluigi

    2015-01-01

    Solid-State NMR spectroscopy of proteins is a notoriously low-throughput technique. Relatively low-sensitivity and poor resolution of protein samples require long acquisition times for multidimensional NMR experiments. To speed up data acquisition, we developed a family of experiments called Polarization Optimized Experiments (POE), in which we utilized the orphan spin operators that are discarded in classical multidimensional NMR experiments, recovering them to allow simultaneous acquisition of multiple 2D and 3D experiments, all while using conventional probes with spectrometers equipped with one receiver. POEs allow the concatenation of multiple 2D or 3D pulse sequences into a single experiment, thus potentially combining all of the aforementioned advances, boosting the capability of ssNMR spectrometers at least two-fold without the addition of any hardware. In this Perspective, we describe the first generation of POEs, such as dual acquisition MAS (or DUMAS) methods, and then illustrate the evolution of these experiments into MEIOSIS, a method that enables the simultaneous acquisition of multiple 2D and 3D spectra. Using these new pulse schemes for the solid-state NMR investigation of biopolymers makes it possible to obtain sequential resonance assignments, as well as distance restraints, in about half the experimental time. While designed for acquisition of heteronuclei, these new experiments can be easily implemented for proton detection and coupled with other recent advancements, such as dynamic polarization, to improve signal to noise. Finally, we illustrate the application of these methods to microcrystalline protein preparations as well as single and multi-span membrane proteins reconstituted in lipid membranes. PMID:25797011

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    Broad Funding Opportunity Announcement Project: Led by MIT professor Donald Sadoway, the Electroville project team is creating a community-scale electricity storage device using new materials and a battery design inspired by the aluminum production process known as smelting. A conventional battery includes a liquid electrolyte and a solid separator between its 2 solid electrodes. MIT’s battery contains liquid metal electrodes and a molten salt electrolyte. Because metals and salt don’t mix, these 3 liquids of different densities naturally separate into layers, eliminating the need for a solid separator. This efficient design significantly reduces packaging materials, which reduces cost and allowsmore » more space for storing energy than conventional batteries offer. MIT’s battery also uses cheap, earth-abundant, domestically available materials and is more scalable. By using all liquids, the design can also easily be resized according to the changing needs of local communities.« less

  19. Characterizing shallow secondary clarifier performance where conventional flux theory over-estimates allowable solids loading rate.

    PubMed

    Daigger, Glen T; Siczka, John S; Smith, Thomas F; Frank, David A; McCorquodale, J A

    The performance characteristics of relatively shallow (3.3 and 3.7 m sidewater depth in 30.5 m diameter) activated sludge secondary clarifiers were extensively evaluated during a 2-year testing program at the City of Akron Water Reclamation Facility (WRF), Ohio, USA. Testing included hydraulic and solids loading stress tests, and measurement of sludge characteristics (zone settling velocity (ZSV), dispersed and flocculated total suspended solids), and the results were used to calibrate computational fluid dynamic (CFD) models of the various clarifiers tested. The results demonstrated that good performance could be sustained at surface overflow rates in excess of 3 m/h, as long as the clarifier influent mixed liquor suspended solids (MLSS) concentration was controlled to below critical values. The limiting solids loading rate (SLR) was significantly lower than the value predicted by conventional solids flux analysis based on the measured ZSV/MLSS relationship. CFD analysis suggested that this resulted because mixed liquor entering the clarifier was being directed into the settled sludge blanket, diluting it and also creating a 'thin' concentration sludge blanket that overlays the thicker concentration sludge blanket typically expected. These results indicate the need to determine the allowable SLR for shallow clarifiers using approaches other than traditional solids flux analysis. A combination of actual testing and CFD analyses are demonstrated here to be effective in doing so.

  20. Packaging of solid state devices

    DOEpatents

    Glidden, Steven C.; Sanders, Howard D.

    2006-01-03

    A package for one or more solid state devices in a single module that allows for operation at high voltage, high current, or both high voltage and high current. Low thermal resistance between the solid state devices and an exterior of the package and matched coefficient of thermal expansion between the solid state devices and the materials used in packaging enables high power operation. The solid state devices are soldered between two layers of ceramic with metal traces that interconnect the devices and external contacts. This approach provides a simple method for assembling and encapsulating high power solid state devices.

  1. Oxygen ionic conductivity of NTE materials of cubic Zr 1- xLn xW 2- yMo yO 8- x/2 (Ln = Er, Yb)

    NASA Astrophysics Data System (ADS)

    Li, Hai-Hua; Xia, Hai-Ting; Jing, Xi-Ping; Zhao, Xin-Hua

    2008-08-01

    Cubic Zr 1- xLn xW 2- yMo yO 8- x/2 (Ln = Er: x = 0.01, 0.02, 0.03; y = 0; Ln = Yb: x = 0.02, 0.03; y = 0.4) solid solutions, well-known negative thermal expansion (NTE) materials were prepared by using conventional solid state reactions. The morphology and the composition of the fracture surfaces of the ceramic pellets were determined by SEM and EDX technology. The conductance properties of the pellets, such as conductivity and conductance activation energy, were studied by AC impedance spectroscopy and the materials perform clearly oxygen ionic conduction with the conductivity of about 10 -4 S cm -1 at 673 K, a comparable value to that of ceria based solid electrolytes. The substitution of Mo for W enhanced the thermal stability of ZrW 2O 8, so that the conductivity of Zr 0.98Yb 0.02W 1.6Mo 0.4O 7.99 ceramic can be measured up to 873 K, which is about 5.9 × 10 -4 S cm -1.

  2. Biogasification of Walt Disney World biomass waste blend. Final report, January 1982-December 1985

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biljetina, R.; Chynoweth, D.P.; Srivastava, V.J.

    1986-10-01

    The objective of the research is to develop efficient processes for conversion of biomass-waste blends to methane and other resources. To evaluate the technical and economic feasibility, an experimental test unit (ETU) was designed and operated at the Reedy Creek Wastewater Treatment Plant at Walt Disney World in Lake Buena Vista, Florida. The facility integrates a biomethanogenic-conversion process with a wastewater-treatment process employing water hyacinth ponds for secondary and tertiary treatment of sewage. Harvested water hyacinth is subsequently combined with sludge from the primary wastewater clarifier and fed at 1-wet-ton per day to the ETU digester. This results in themore » production of methane and other useful products. The digester was operated as a non-mixed, solids concentrating digester to encourage higher solids and microorganism retention times. Data collected during six steady-state operating periods confirmed earlier laboratory observations that this digester consistently produces 15 to 25% higher methane yields and conversions when compared to conventional stirred-tank digester. Digester operation was evaluated at different loading rates, solids blend ratios and feed configurations. Results from the program have provided a data base for the design of larger conversion systems.« less

  3. Facile synthesis of Li2S-P2S5 glass-ceramics electrolyte with micron range particles for all-solid-state batteries via a low-temperature solution technique (LTST)

    NASA Astrophysics Data System (ADS)

    Choi, Sunho; Lee, Sewook; Park, Jongyeop; Nichols, William T.; Shin, Dongwook

    2018-06-01

    A lithium ion conductive 75Li2Sṡ25P2S5 glass-ceramics electrolyte is, for the first time, successfully synthesized via a new low-temperature solution technique (LTST) and compared to the conventional mechanical-milling technique. Both samples are composed of the highly lithium ion conductive thio-LISICON III analog phase. Due to the uniform dispersion of reactants in an organic liquid, the use of LTST produced significantly smaller and more uniform particle sizes (2.2 ± 1.68 μm) resulting in a 6.5 times higher specific surface area compared to the mechanically-milled sample. A pronounced enhancement of both the rate capability and cyclability is demonstrated for the LTST solid electrolyte sample due to the more intimate contact with the LiCoO2 active material. Furthermore, the LTST sample shows excellent electrochemical stability throughout the potential range of -1 to 5 V. These results suggest that the proposed technique using the optimized LTST process is promising for the preparation of 75Li2Sṡ25P2S5 solid electrolytes for use in advanced Li-ion batteries.

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kobayashi, Takeshi; Singappuli-Arachchige, Dilini; Wang, Zhuoran

    Solid-state NMR spectroscopy, both conventional and dynamic nuclear polarization (DNP)-enhanced, was employed to study the spatial distribution of organic functional groups attached to the surface of mesoporous silica nanoparticles via co-condensation and grafting. The most revealing information was provided by DNP-enhanced two-dimensional 29Si– 29Si correlation measurements, which unambiguously showed that post-synthesis grafting leads to a more homogeneous dispersion of propyl and mercaptopropyl functionalities than co-condensation. Furthermore, during the anhydrous grafting process, the organosilane precursors do not self-condense and are unlikely to bond to the silica surface in close proximity (less than 4 Å) due to the limited availability of suitablymore » arranged hydroxyl groups.« less

  5. Production of 35S for a Liquid Semiconductor Betavoltaic

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meier, David E.; Garnov, A. Y.; Robertson, J. D.

    2009-10-01

    The specific energy density from radioactive decay is five to six orders of magnitude greater than the specific energy density in conventional chemical battery and fuel cell technologies. We are currently investigating the use of liquid semiconductor based betavoltaics as a way to directly convert the energy of radioactive decay into electrical power and potentially avoid the radiation damage that occurs in solid state semiconductor devices due to non-ionizing energy loss. Sulfur-35 was selected as the isotope for the liquid semiconductor demonstrations because it can be produced in high specific activity and it is chemically compatible with known liquid semiconductormore » media.« less

  6. Design of Phosphonated Imidazolium-Based Ionic Liquids Grafted on γ-Alumina: Potential Model for Hybrid Membranes

    PubMed Central

    Pizzoccaro, Marie-Alix; Drobek, Martin; Petit, Eddy; Guerrero, Gilles; Hesemann, Peter; Julbe, Anne

    2016-01-01

    Imidazolium bromide-based ionic liquids bearing phosphonyl groups on the cationic part were synthesized and grafted on γ-alumina (γ-Al2O3) powders. These powders were prepared as companion samples of conventional mesoporous γ-alumina membranes, in order to favor a possible transfer of the results to supported membrane materials, which could be used for CO2 separation applications. Effective grafting was demonstrated using energy dispersive X-ray spectrometry (EDX), N2 adsorption measurements, fourier transform infrared spectroscopy (FTIR), and special attention was paid to 31P and 13C solid state nuclear magnetic resonance spectroscopy (NMR). PMID:27472321

  7. Welding parameter optimization of alloy material by friction stir welding using Taguchi approach and design of experiments

    NASA Astrophysics Data System (ADS)

    Karwande, Amit H.; Rao, Seeram Srinivasa

    2018-04-01

    Friction stir welding (FSW) a welding process in which metals are joint by melting them at their solid state. In different engineering areas such as civil, mechanical, naval and aeronautical engineering beams are widely used of the magnesium alloys for different applications and that are joined by conventional inert gas welding process. Magnesium metal has less density and low melting point for that reason large heat generation in the common welding process so its necessity to adapt new welding process. FSW process increases the weld quality which observed under various mechanical testing by using different tool size.

  8. Lattice Vibrations Boost Demagnetization Entropy in Shape Memory Alloy

    DOE PAGES

    Stonaha, Paul J.; Manley, Michael E.; Bruno, Nick; ...

    2015-10-07

    Magnetocaloric (MC) materials present an avenue for chemical-free, solid state refrigeration through cooling via adiabatic demagnetization. We have used inelastic neutron scattering to measure the lattice dynamics in the MC material Ni 45Co 5Mn 36.6In 13.4. Upon heating across TC, the material exhibits an anomalous increase in phonon entropy of 0.17 0.04 k_B/atom, which is nine times larger than expected from conventional thermal expansion. We find that the phonon softening is focused in a transverse optic phonon, and we present the results of first-principle calculations which predict a strong coupling between lattice distortions and magnetic excitations.

  9. All-femtosecond laser-assisted in situ keratomileusis

    NASA Astrophysics Data System (ADS)

    Gabryte, Egle; Danieliene, Egle; Vaiceliunaite, Agne; Ruksenas, Osvaldas; Vengris, Mikas; Danielius, Romualdas

    2013-03-01

    We present a femtosecond solid-state Yb:KGW laser system capable of performing the complete laser-assisted in situ keratomileusis (LASIK) ophthalmic procedure. The fundamental infrared radiation (IR) is used to create the corneal flap, and subsequently the corneal stromal ablation is performed using the ultraviolet (UV) pulses of the fifth harmonic. The heating of cornea, ablated surface quality, and healing outcomes of the surgeries performed using the femtosecond laser system are investigated by both ex vivo and in vivo experiments and compared to the results of conventional clinical ArF excimer laser application. The results of this research indicate the feasibility of clinical application of femtosecond UV lasers for LASIK procedure.

  10. Mixed-Mode Decohesion Elements for Analyses of Progressive Delamination

    NASA Technical Reports Server (NTRS)

    Davila, Carlos G.; Camanho, Pedro P.; deMoura, Marcelo F.

    2001-01-01

    A new 8-node decohesion element with mixed mode capability is proposed and demonstrated. The element is used at the interface between solid finite elements to model the initiation and propagation of delamination. A single displacement-based damage parameter is used in a strain softening law to track the damage state of the interface. The method can be used in conjunction with conventional material degradation procedures to account for inplane and intra-laminar damage modes. The accuracy of the predictions is evaluated in single mode delamination tests, in the mixed-mode bending test, and in a structural configuration consisting of the debonding of a stiffener flange from its skin.

  11. Ferromagnetic interactions in chromium (III) doped YMnO3

    NASA Astrophysics Data System (ADS)

    Thakur, Rajesh K.; Thakur, Rasna; Kaurav, N.; Okram, G. S.; Gaur, N. K.

    2016-05-01

    Both of the reported compounds with compositions YMn1-xCrxO3 (x = 0.1 and 0.2) are synthesized by using the conventional solid state reaction method and their magnetic properties are analyzed vigilantly. The XRD pattern reveals the hexagonal structure of the reported compounds with space group P63cm (25-1079). The in-depth analysis of the magnetic measurements reveals the enhancement in the ferromagnetic character with Cr doping in YMnO3 compounds. The observed enhancement in the ferromagnetism is found to be due to the increased double exchange interactions among the Cr3+ and Mn3+ ions with Cr doping.

  12. The aggregation of the merocyanine dyes, depending of the type of the counterions.

    PubMed

    Kolev, Tsonko; Koleva, Bojidarka B; Stoyanov, Stanimir; Spiteller, Michael; Petkov, Ivan

    2008-10-01

    Counterions affect on the substructures formation in the case of the merocyanine dye, 1-methyl-4-[2-(4-hydroxyphenyl)ethenyl)]piridinium] hydrogensquarate both in gas and condense phase. Spectroscopically and structural elucidation of these aggregates have been performed, using solid-state conventional and linear-polarized IR-spectroscopy of oriented colloids as a nematic liquid crystal suspension, UV-vis spectroscopy, HPLC tandem ESI mass spectrometry, 1H and 13C NMR, TGV and DSC. Quantum chemical DFT calculations have been carried out as well. Experimental and theoretical data are compared with analogous ones of corresponding iodide salt of dye studied.

  13. Enhancement of Curie temperature of barium hexaferrite by dense electronic excitations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sharma, Manju; Kashyap, Subhash C.; Gupta, Hem C.

    2014-07-15

    Curie temperature of polycrystalline barium hexaferrite (BaFe{sub 12}O{sub 19}), prepared by conventional solid state technique, is anomalously and significantly enhanced (by nearly 15%) by energetic heavy ion irradiation (150 MeV, Ag{sup 12+}) at ambient temperature due to dense electronic excitations Moderate fluence (1 × 10{sup 12} ions/cm{sup 2}) induces structural defects giving rise to above enhancement. As established by X-ray diffraction, scanning electron microscopy and Raman studies, higher fluence (1 × 10{sup 13} ions/cm{sup 2}) has structurally transformed the sample to amorphous phase with marginal change in magnetization and Curie temperature.

  14. Bubble template synthesis of Sn2Nb2O7 hollow spheres for enhanced visible-light-driven photocatalytic hydrogen production.

    PubMed

    Zhou, Chao; Zhao, Yufei; Bian, Tong; Shang, Lu; Yu, Huijun; Wu, Li-Zhu; Tung, Chen-Ho; Zhang, Tierui

    2013-10-28

    Hierarchical Sn2Nb2O7 hollow spheres were prepared for the first time via a facile hydrothermal route using bubbles generated in situ from the decomposition of urea as soft templates. The as-obtained hollow spheres with a large specific surface area of 58.3 m(2) g(-1) show improved visible-light-driven photocatalytic H2 production activity in lactic acid aqueous solutions, about 4 times higher than that of the bulk Sn2Nb2O7 sample prepared by a conventional high temperature solid state reaction method.

  15. Development of a high power density 2.5 kW class solid oxide fuel cell stack

    NASA Astrophysics Data System (ADS)

    Yokoo, M.; Mizuki, K.; Watanabe, K.; Hayashi, K.

    2011-10-01

    We have developed a 2.5 kW class solid oxide fuel cell stack. It is constructed by combining 70 power generation units, each of which is composed of an anode-supported planar cell and separators. The power generation unit for the 2.5 kW class stack were designed so that the height of the unit were scaled down by 2/3 of that for our conventional 1.5 kW class stack. The power generation unit for the 2.5 kW class stack provided the same output as the unit used for the conventional 1.5 kW class stack, which means that power density per unit volume of the 2.5 kW class stack was 50% greater than that of the conventional 1.5 kW class stack.

  16. Space Commercialization and the Development of Space Law

    NASA Astrophysics Data System (ADS)

    Yun, Zhao

    2017-05-01

    Shortly after the launch of the first manmade satellite in 1957, the United Nations (UN) took the lead in formulating international rules governing space activities. The five international conventions (i.e., the 1967 Outer Space Treaty, the 1968 Rescue Agreement, the 1972 Liability Convention, the 1975 Registration Convention, and the 1979 Moon Agreement) within the UN framework constitute the nucleus of space law; laying a solid legal foundation for securing the smooth development of space activities over the next few decades. Outer space was soon found to be a place with abundant opportunities for commercialization: with telecommunications services the first and most successful commercial application followed by remote sensing and global navigation services. In the last decade, the rapid development of space technologies brought space tourism and space mining to the forefront as well. With more and more commercial activities taking place on a daily basis from the 1980s on, existing space law faces severe challenges. The five conventions, which were enacted at a time when space was monopolized by two superpowers—the United States and the former Soviet Union—also failed to take into account the commercial aspect of space activities. Although there are urgent needs for new rules to deal with the ongoing trend of space commercialization, the international society faces difficulties in adopting new rules due to diversified national interests. As a result, it adjusts legislative strategies by enacting soft laws. In view of the difficulty in adopting binding rules at the international level, states are encouraged to enact their own national space legislation providing sufficient guidance for their domestic space commercial activities. It is expected that the development of soft laws and national space legislation will be the mainstream regulatory activities in the space field for the foreseeable future.

  17. Integration of nanoscale memristor synapses in neuromorphic computing architectures

    NASA Astrophysics Data System (ADS)

    Indiveri, Giacomo; Linares-Barranco, Bernabé; Legenstein, Robert; Deligeorgis, George; Prodromakis, Themistoklis

    2013-09-01

    Conventional neuro-computing architectures and artificial neural networks have often been developed with no or loose connections to neuroscience. As a consequence, they have largely ignored key features of biological neural processing systems, such as their extremely low-power consumption features or their ability to carry out robust and efficient computation using massively parallel arrays of limited precision, highly variable, and unreliable components. Recent developments in nano-technologies are making available extremely compact and low power, but also variable and unreliable solid-state devices that can potentially extend the offerings of availing CMOS technologies. In particular, memristors are regarded as a promising solution for modeling key features of biological synapses due to their nanoscale dimensions, their capacity to store multiple bits of information per element and the low energy required to write distinct states. In this paper, we first review the neuro- and neuromorphic computing approaches that can best exploit the properties of memristor and scale devices, and then propose a novel hybrid memristor-CMOS neuromorphic circuit which represents a radical departure from conventional neuro-computing approaches, as it uses memristors to directly emulate the biophysics and temporal dynamics of real synapses. We point out the differences between the use of memristors in conventional neuro-computing architectures and the hybrid memristor-CMOS circuit proposed, and argue how this circuit represents an ideal building block for implementing brain-inspired probabilistic computing paradigms that are robust to variability and fault tolerant by design.

  18. Solid state recorders for airborne reconnaissance

    NASA Astrophysics Data System (ADS)

    Klang, Mark R.

    2003-08-01

    Solid state recorders have become the recorder of choice for meeting airborne ruggedized requirements for reconnaissance and flight test. The cost of solid state recorders have decreased over the past few years that they are now less expense than the traditional high speed tape recorders. CALCULEX, Inc manufactures solid state recorders called MONSSTR (Modular Non-volatile Solid State Recorder). MONSSTR is being used on many different platforms such as F/A-22, Global Hawk, F-14, F-15, F-16, U-2, RF-4, and Tornado. This paper will discuss the advantages of using solid state recorders to meet the airborne reconnaissance requirement and the ability to record instrumentation data. The CALCULEX recorder has the ability to record sensor data and flight test data in the same chassis. This is an important feature because it eliminates additional boxes on the aircraft. The major advantages to using a solid state recorder include; reliability, small size, light weight, and power. Solid state recorders also have a larger storage capacity and higher bandwidth capability than other recording devices.

  19. The solid-state terahertz spectrum of MDMA (Ecstasy) - A unique test for molecular modeling assignments

    NASA Astrophysics Data System (ADS)

    Allis, Damian G.; Hakey, Patrick M.; Korter, Timothy M.

    2008-10-01

    The terahertz (THz, far-infrared) spectrum of 3,4-methylene-dioxymethamphetamine hydrochloride (Ecstasy) is simulated using solid-state density functional theory. While a previously reported isolated-molecule calculation is noteworthy for the precision of its solid-state THz reproduction, the solid-state calculation predicts that the isolated-molecule modes account for only half of the spectral features in the THz region, with the remaining structure arising from lattice vibrations that cannot be predicted without solid-state molecular modeling. The molecular origins of the internal mode contributions to the solid-state THz spectrum, as well as the proper consideration of the protonation state of the molecule, are also considered.

  20. 30 CFR 70.207 - Bimonthly sampling; mechanized mining units.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... sampling device as follows: (1) Conventional section using cutting machine. On the cutting machine operator or on the cutting machine within 36 inches inby the normal working position; (2) Conventional section shooting off the solid. On the loading machine operator or on the loading machine within 36 inches inby the...

  1. 30 CFR 70.207 - Bimonthly sampling; mechanized mining units.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sampling device as follows: (1) Conventional section using cutting machine. On the cutting machine operator or on the cutting machine within 36 inches inby the normal working position; (2) Conventional section shooting off the solid. On the loading machine operator or on the loading machine within 36 inches inby the...

  2. 30 CFR 70.207 - Bimonthly sampling; mechanized mining units.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... sampling device as follows: (1) Conventional section using cutting machine. On the cutting machine operator or on the cutting machine within 36 inches inby the normal working position; (2) Conventional section shooting off the solid. On the loading machine operator or on the loading machine within 36 inches inby the...

  3. Enhanced solubility and bioavailability of sibutramine base by solid dispersion system with aqueous medium.

    PubMed

    Li, Dong Xun; Jang, Ki-Young; Kang, Wonku; Bae, Kyoungjin; Lee, Mann Hyung; Oh, Yu-Kyoung; Jee, Jun-Pil; Park, Young-Joon; Oh, Dong Hoon; Seo, Youn Gee; Kim, Young Ran; Kim, Jong Oh; Woo, Jong Soo; Yong, Chul Soon; Choi, Han-Gon

    2010-01-01

    To develop a novel sibutramine base-loaded solid dispersion with improved solubility bioavailability, various solid dispersions were prepared with water, hydroxypropylmethyl cellulose (HPMC), poloxamer and citric acid using spray-drying technique. The effect of HPMC, poloxamer and citric acid on the aqueous solubility of sibutramine was investigated. The physicochemical properties of solid dispersion were investigated using scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and X-ray powder diffraction. The dissolution and pharmacokinetics in rats of solid dispersion were evaluated compared to the sibutramine hydrochloride monohydrate-loaded commercial product (Reductil). The sibutramine base-loaded solid dispersion gave two type forms. Like conventional solid dispersion system, one type appeared as a spherical shape with smooth surface, as the carriers and drug with relatively low melting point were soluble in water and formed it. The other appeared as an irregular form with relatively rough surface. Unlike conventional solid dispersion system, this type changed no crystalline form of drug. Our results suggested that this type was formed by attaching hydrophilic carriers to the surface of drug without crystal change, resulting from changing the hydrophobic drug to hydrophilic form. The sibutramine-loaded solid dispersion at the weight ratio of sibutramine base/HPMC/poloxamer/citric acid of 5/3/3/0.2 gave the maximum drug solubility of about 3 mg/ml. Furthermore, it showed the similar plasma concentration, area under the curve (AUC) and C(max) of parent drug, metabolite I and II to the commercial product, indicating that it might give the similar drug efficacy compared to the sibutramine hydrochloride monohydrate-loaded commercial product in rats. Thus, this solid dispersion system would be useful to deliver poorly water-soluble sibutramine base with enhanced bioavailability.

  4. Solid state lighting devices and methods with rotary cooling structures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koplow, Jeffrey P.

    Solid state lighting devices and methods for heat dissipation with rotary cooling structures are described. An example solid state lighting device includes a solid state light source, a rotating heat transfer structure in thermal contact with the solid state light source, and a mounting assembly having a stationary portion. The mounting assembly may be rotatably coupled to the heat transfer structure such that at least a portion of the mounting assembly remains stationary while the heat transfer structure is rotating. Examples of methods for dissipating heat from electrical devices, such as solid state lighting sources are also described. Heat dissipationmore » methods may include providing electrical power to a solid state light source mounted to and in thermal contact with a heat transfer structure, and rotating the heat transfer structure through a surrounding medium.« less

  5. Effect of Microstructure on the Radioluminescence and Transparency of Ce-Doped Strontium Hafnate Ceramics

    PubMed Central

    van Loef, Edgar V.; Wang, Yimin; Miller, Stuart R.; Brecher, Charles; Rhodes, William H.; Baldoni, Gary; Topping, Stephen; Lingertat, Helmut; Sarin, Vinod K.; Shah, Kanai S.

    2011-01-01

    In this paper we report on the fabrication and characterization of SrHfO3:Ce ceramics. Powders were prepared by solid-state synthesis using metal oxides and carbonates. X-ray diffraction measurements showed that phase-pure SrHfO3 is formed at 1200°C. Inductively coupled plasma spectroscopy confirmed the purity and composition of each batch. SrHfO3 exhibits several phase changes in the solid, but this does not appear to be detrimental to the ceramics. Microprobe experiments showed uniform elemental grain composition, whereas aluminum added as charge compensation for trivalent cerium congregated at grain boundaries and triple points. Radioluminescence spectra revealed that the light yield decreases when the concentration of excess Sr increases. The decrease in the light yield may be related to the change of Ce3+ into Ce4+ ions. For stoichiometric SrHfO3:Ce, the light yield is about four times that of bismuth germanate (BGO), the conventional benchmark, indicating great potential for many scintillator applications. PMID:21339835

  6. Dispersion of the Photosensitizer 5,10,15,20-Tetrakis(4-Sulfonatophenyl)-porphyrin by the Amphiphilic Polymer Poly(vinylpirrolidone) in Highly Porous Solid Materials Designed for Photodynamic Therapy.

    PubMed

    Díaz, Claudia; Catalán-Toledo, José; Flores, Mario E; Orellana, Sandra L; Pesenti, Héctor; Lisoni, Judit; Moreno-Villoslada, Ignacio

    2017-08-03

    The ability of the amphiphilic and biocompatible poly(vinylpyrrolidone) to avoid self-aggregation of the photosensitizer 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin in aqueous solution in the presence of the biocompatible polycation chitosan, polymer that induces the dye self-aggregation, is shown. This is related to the tendency of the dye to undergo preferential solvation by the amphiphilic polymer. Importantly, the dispersant ability of this polymer is transferred to the solid state. Thus, aerogels made of the biocompatible polymers chitosan and chondroitin sulfate, and containing the photosensitizer dispersed by the amphiphilic polymer have been synthesized. Production of reactive oxygen species by the aerogel containing the amphiphilic polymer was faster than when the polymer was absent, correlating with the relative concentration of dyes dispersed as monomers. The aerogels presented here constitute low cost biocompatible materials bearing a conventional photosensitizer for photodynamic therapy, easy to produce, store, transport, and manage in clinical practice.

  7. An ultra-high gain and efficient amplifier based on Raman amplification in plasma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vieux, G.; Cipiccia, S.; Grant, D. W.

    Raman amplification arising from the excitation of a density echelon in plasma could lead to amplifiers that significantly exceed current power limits of conventional laser media. Here we show that 1–100 J pump pulses can amplify picojoule seed pulses to nearly joule level. The extremely high gain also leads to significant amplification of backscattered radiation from “noise”, arising from stochastic plasma fluctuations that competes with externally injected seed pulses, which are amplified to similar levels at the highest pump energies. The pump energy is scattered into the seed at an oblique angle with 14 J sr -1, and net gainsmore » of more than eight orders of magnitude. The maximum gain coefficient, of 180 cm -1, exceeds high-power solid-state amplifying media by orders of magnitude. The observation of a minimum of 640 J sr -1 directly backscattered from noise, corresponding to ≈10% of the pump energy in the observation solid angle, implies potential overall efficiencies greater than 10%.« less

  8. An ultra-high gain and efficient amplifier based on Raman amplification in plasma

    DOE PAGES

    Vieux, G.; Cipiccia, S.; Grant, D. W.; ...

    2017-05-25

    Raman amplification arising from the excitation of a density echelon in plasma could lead to amplifiers that significantly exceed current power limits of conventional laser media. Here we show that 1–100 J pump pulses can amplify picojoule seed pulses to nearly joule level. The extremely high gain also leads to significant amplification of backscattered radiation from “noise”, arising from stochastic plasma fluctuations that competes with externally injected seed pulses, which are amplified to similar levels at the highest pump energies. The pump energy is scattered into the seed at an oblique angle with 14 J sr -1, and net gainsmore » of more than eight orders of magnitude. The maximum gain coefficient, of 180 cm -1, exceeds high-power solid-state amplifying media by orders of magnitude. The observation of a minimum of 640 J sr -1 directly backscattered from noise, corresponding to ≈10% of the pump energy in the observation solid angle, implies potential overall efficiencies greater than 10%.« less

  9. An innovative combined on-site process for the remote rural solid waste treatment--a pilot scale case study in China.

    PubMed

    Li, Wen-Bing; Yao, Jun; Tao, Ping-Ping; Hu, Hong; Fang, Cheng-Ran; Shen, Dong-Sheng

    2011-03-01

    The aim of this study was to find a feasible method for the treatment of solid waste generated in the remote rural, where the transportation costs are prohibitive and the resources to construct and maintain conventional treatment plants are not available. This process, consisted of two types of simulated bioreactor landfill (one was recirculated bioreactor landfill, and the other was comprised of fresh and aged refuse reactor) and a soil infiltration system, was operated in ambient temperature for 180 days all together. After treated by the system of fresh and aged refuse reactor, the refuse and leachate reached a strongly degraded and stable state. The remaining leachate can be treated by the soil infiltration system, and 87.5 ± 2.1%, 98.6 ± 1.0% and 95.7 ± 1.7% were achieved by 60 cm soil depths for organic matter, ammonium nitrogen and total nitrogen removal, respectively. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Measuring the electron affinity of organic solids: an indispensable new tool for organic electronics.

    PubMed

    Yoshida, Hiroyuki

    2014-04-01

    Electron affinity is a fundamental energy parameter of materials. In organic semiconductors, the electron affinity is closely related to electron conduction. It is not only important to understand fundamental electronic processes in organic solids, but it is also indispensable for research and development of organic semiconductor devices such as organic light-emitting diodes and organic photovoltaic cells. However, there has been no experimental technique for examining the electron affinity of organic materials that meets the requirements of such research. Recently, a new method, called low-energy inverse-photoemission spectroscopy, has been developed. A beam of low-energy electrons is focused onto the sample surface, and photons emitted owing to the radiative transition to unoccupied states are then detected. From the onset of the spectral intensity, the electron affinity is determined within an uncertainty of 0.1 eV. Unlike in conventional inverse-photoemission spectroscopy, sample damage is negligible and the resolution is improved by a factor of 2. The principle of the method and several applications are reported.

  11. A Rechargeable High-Temperature Molten Salt Iron-Oxygen Battery.

    PubMed

    Peng, Cheng; Guan, Chengzhi; Lin, Jun; Zhang, Shiyu; Bao, Hongliang; Wang, Yu; Xiao, Guoping; Chen, George Zheng; Wang, Jian-Qiang

    2018-06-11

    The energy and power density of conventional batteries are far lower than their theoretical expectations, primarily because of slow reaction kinetics that are often observed under ambient conditions. Here we describe a low-cost and high-temperature rechargeable iron-oxygen battery containing a bi-phase electrolyte of molten carbonate and solid oxide. This new design merges the merits of a solid-oxide fuel cell and molten metal-air battery, offering significantly improved battery reaction kinetics and power capability without compromising the energy capacity. The as-fabricated battery prototype can be charged at high current density, and exhibits excellent stability and security in the highly charged state. It typically exhibits specific energy, specific power, energy density, and power density of 129.1 Wh kg -1 , 2.8 kW kg -1 , 388.1 Wh L -1 , and 21.0 kW L -1 , respectively, based on the mass and volume of the molten salt. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Prediction of Phase Behavior of Spray-Dried Amorphous Solid Dispersions: Assessment of Thermodynamic Models, Standard Screening Methods and a Novel Atomization Screening Device with Regard to Prediction Accuracy

    PubMed Central

    Chavez, Pierre-François; Meeus, Joke; Robin, Florent; Schubert, Martin Alexander; Somville, Pascal

    2018-01-01

    The evaluation of drug–polymer miscibility in the early phase of drug development is essential to ensure successful amorphous solid dispersion (ASD) manufacturing. This work investigates the comparison of thermodynamic models, conventional experimental screening methods (solvent casting, quench cooling), and a novel atomization screening device based on their ability to predict drug–polymer miscibility, solid state properties (Tg value and width), and adequate polymer selection during the development of spray-dried amorphous solid dispersions (SDASDs). Binary ASDs of four drugs and seven polymers were produced at 20:80, 40:60, 60:40, and 80:20 (w/w). Samples were systematically analyzed using modulated differential scanning calorimetry (mDSC) and X-ray powder diffraction (XRPD). Principal component analysis (PCA) was used to qualitatively assess the predictability of screening methods with regards to SDASD development. Poor correlation was found between theoretical models and experimentally-obtained results. Additionally, the limited ability of usual screening methods to predict the miscibility of SDASDs did not guarantee the appropriate selection of lead excipient for the manufacturing of robust SDASDs. Contrary to standard approaches, our novel screening device allowed the selection of optimal polymer and drug loading and established insight into the final properties and performance of SDASDs at an early stage, therefore enabling the optimization of the scaled-up late-stage development. PMID:29518936

  13. Sr- and Nb-co-doped Li7La3Zr2O12 solid electrolyte with Al2O3 addition towards high ionic conductivity

    NASA Astrophysics Data System (ADS)

    Lin, Changwei; Tang, Yu; Song, Jun; Han, Lei; Yu, Jingbo; Lu, Anxian

    2018-06-01

    In the present study, series of garnet-type Li6.75+ x La3- x Sr x Zr1.75Nb0.25O12 solid electrolytes [LLSZN with various Sr contents ( x = 0.05-0.25)] have been prepared via conventional solid-state method. The effects of Sr contents on their phase structure and ionic conductivity have been systematically investigated on the combined measurements of X-ray diffraction and scanning electron microscopy and alter current impedance spectroscopy. Our results reveal that a phase transition from tetragonal to cubic structure occurs when both Sr and Nb elements is introduced, and such a cubic structure can be stable over the whole Sr contents variation, which is suggested to provide a beneficial impact on the performance of LLSZN. Accordingly, both relative density and total ionic conductivity exhibit a favorable tendency of increasing first and then decreasing with increased Sr contents, wherein a peak value at 93.46% and 5.09 × 10-4 S cm-1, respectively, can be well achieved. Particularly, the maximum ionic conductivity is almost twice that of the compared sample (2.93 × 10-4 S cm-1), and possess the minimum activation energy 0.30 eV. Such a modification method, featured with higher efficiency and lower cost, is expected to be helpful for the development of solid electrolyte.

  14. In-situ shear stress indicator using heated strain gages at the flow boundary

    NASA Astrophysics Data System (ADS)

    Yeh, Chi-An; Yang, Fuling

    2011-11-01

    This work borrows the concept of hot-wire anemometry and sketch a technique that uses local heat transfer to infer the flow field and the corresponding stress. Conventional strain gages were mounted at the flow solid boundary as the heat source and acrylic boundary was chosen for its low thermal conductivity ensuring heat accumulation when a gage is energized. The gage would now work in slightly overheated state and its self-heating leads to an additional thermal strain. When exposed to a flow field, heat is brought away by local forced convection, resulting in deviations in gage signal from that developed in quiescent liquid. We have developed a facility to achieve synchronous gage measurements at different locations on a solid boundary. Three steady flow motions were considered: circular Couette flow, rectilinear uniform flow, and rectilinear oscillating flow. Preliminary tests show the gage reading does respond to the imposed flow through thermal effects and greater deviation was measured in flows of higher shear strain rates. The correlation between the gage signals and the imposed flow field is further examined by theoretical analysis. We also introduced a second solid boundary to the vicinity of the gage in the two rectilinear flows. The gage readings demonstrate rises in its magnitudes indicating wall amplification effect on the local shear strain, agreeing to the drag augmentation by a second solid boundary reported in many multiphase flow literatures.

  15. Quantum model of a solid-state spin qubit: Ni cluster on a silicon surface by the generalized spin Hamiltonian and X-ray absorption spectroscopy investigations

    NASA Astrophysics Data System (ADS)

    Farberovich, Oleg V.; Mazalova, Victoria L.; Soldatov, Alexander V.

    2015-11-01

    We present here the quantum model of a Ni solid-state electron spin qubit on a silicon surface with the use of a density-functional scheme for the calculation of the exchange integrals in the non-collinear spin configurations in the generalized spin Hamiltonian (GSH) with the anisotropic exchange coupling parameters linking the nickel ions with a silicon substrate. In this model the interaction of a spin qubit with substrate is considered in GSH at the calculation of exchange integrals Jij of the nanosystem Ni7-Si in the one-electron approach taking into account chemical bonds of all Si-atoms of a substrate (environment) with atoms of the Ni7-cluster. The energy pattern was found from the effective GSH Hamiltonian acting in the restricted spin space of the Ni ions by the application of the irreducible tensor operators (ITO) technique. In this paper we offer the model of the quantum solid-state N-spin qubit based on the studying of the spin structure and the spin-dynamics simulations of the 3d-metal Ni clusters on the silicon surface. The solution of the problem of the entanglement between spin states in the N-spin systems is becoming more interesting when considering clusters or molecules with a spectral gap in their density of states. For quantifying the distribution of the entanglement between the individual spin eigenvalues (modes) in the spin structure of the N-spin system we use the density of entanglement (DOE). In this study we have developed and used the advanced high-precision numerical techniques to accurately assess the details of the decoherence process governing the dynamics of the N-spin qubits interacting with a silicon surface. We have studied the Rabi oscillations to evaluate the N-spin qubits system as a function of the time and the magnetic field. We have observed the stabilized Rabi oscillations and have stabilized the quantum dynamical qubit state and Rabi driving after a fixed time (0.327 μs). The comparison of the energy pattern with the anisotropic exchange models conventionally used for the analysis of this system and, with the results of the experimental XANES spectra, shows that our complex investigations provide a good description of the pattern of the spin levels and the spin structures of the nanomagnetic Ni7 qubit. The results are discussed in the view of the general problem of the solid-state spin qubits and the spin structure of the Ni cluster.

  16. Dynamic Jahn-Teller effect in the parent insulating state of the molecular superconductor Cs₃C₆₀.

    PubMed

    Klupp, Gyöngyi; Matus, Péter; Kamarás, Katalin; Ganin, Alexey Y; McLennan, Alec; Rosseinsky, Matthew J; Takabayashi, Yasuhiro; McDonald, Martin T; Prassides, Kosmas

    2012-06-19

    The 'expanded fulleride' Cs(3)C(60) is an antiferromagnetic insulator in its normal state and becomes a molecular superconductor with T(c) as high as 38 K under pressure. There is mounting evidence that superconductivity is not of the conventional BCS type and electron-electron interactions are essential for its explanation. Here we present evidence for the dynamic Jahn-Teller effect as the source of the dramatic change in electronic structure occurring during the transition from the metallic to the localized state. We apply infrared spectroscopy, which can detect subtle changes in the shape of the C(60)3- ion due to the Jahn-Teller distortion. The temperature dependence of the spectra in the insulating phase can be explained by the gradual transformation from two temperature-dependent solid-state conformers to a single one, typical and unique for Jahn-Teller systems. These results unequivocally establish the relevance of the dynamic Jahn-Teller effect to overcoming Hund's rule and forming a low-spin state, leading to a magnetic Mott-Jahn-Teller insulator.

  17. Sequential Anaerobic/Aerobic Digestion for Enhanced Carbon/Nitrogen Removal and Cake Odor Reduction.

    PubMed

    Ahmad, Muneer; Denee, Marco Abel; Jiang, Hao; Eskicioglu, Cigdem; Kadota, Paul; Gregonia, Theresa

    2016-12-01

      Anaerobic digestion (AD) has been proven to be an effective process for the treatment of wastewater sludge. However, it produces high levels of ammonia in the digester effluent, which may jeopardize meeting stringent nutrient discharge limits. In this study, the effect of a sequential anaerobic/aerobic (AN/AERO) digestion and a single-stage conventional AN digestion (as control) was investigated on mixed (primary + secondary) sludge generated by the Annacis Island wastewater treatment plant (WWTP) (BC, Canada). An overall sludge retention time (SRT) of 22.5 days under three different scenarios was chosen based on the current operational SRT of the digesters at the Annacis Island WWTP. The steady state results have shown that sequential AN/AERO digestion configurations achieved up to 11% higher volatile solids (VS) removal and 72% lower ammonia generation over single-stage conventional AN digestion. Furthermore, sequential AN/AERO system also showed enhanced dewaterability, improved fecal coliform destruction and reduced digested cake odors over control digesters.

  18. Conventional empirical law reverses in the phase transitions of 122-type iron-based superconductors

    DOE PAGES

    Yu, Zhenhai; Wang, Lin; Wang, Luhong; ...

    2014-11-24

    Phase transition of solid-state materials is a fundamental research topic in condensed matter physics, materials science and geophysics. It has been well accepted and widely proven that isostructural compounds containing different cations undergo same pressure-induced phase transitions but at progressively lower pressures as the cation radii increases. However, we discovered that this conventional law reverses in the structural transitions in 122-type iron-based superconductors. In this report, a combined low temperature and high pressure X-ray diffraction (XRD) measurement has identified the phase transition curves among the tetragonal (T), orthorhombic (O) and the collapsed-tetragonal (cT) phases in the structural phase diagram ofmore » the iron-based superconductor AFe 2As 2 (A = Ca, Sr, Eu, and Ba). As a result, the cation radii dependence of the phase transition pressure (T → cT) shows an opposite trend in which the compounds with larger ambient radii cations have a higher transition pressure.« less

  19. A major advance in powder metallurgy

    NASA Technical Reports Server (NTRS)

    Williams, Brian E.; Stiglich, Jacob J., Jr.; Kaplan, Richard B.; Tuffias, Robert H.

    1991-01-01

    Ultramet has developed a process which promises to significantly increase the mechanical properties of powder metallurgy (PM) parts. Current PM technology uses mixed powders of various constituents prior to compaction. The homogeneity and flaw distribution in PM parts depends on the uniformity of mixing and the maintenance of uniformity during compaction. Conventional PM fabrication processes typically result in non-uniform distribution of the matrix, flaw generation due to particle-particle contact when one of the constituents is a brittle material, and grain growth caused by high temperature, long duration compaction processes. Additionally, a significant amount of matrix material is usually necessary to fill voids and create 100 percent dense parts. In Ultramet's process, each individual particle is coated with the matrix material, and compaction is performed by solid state processing. In this program, Ultramet coated 12-micron tungsten particles with approximately 5 wt percent nickel/iron. After compaction, flexure strengths were measured 50 percent higher than those achieved in conventional liquid phase sintered parts (10 wt percent Ni/Fe). Further results and other material combinations are discussed.

  20. Development of techniques in magnetic resonance and structural studies of the prion protein

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bitter, Hans-Marcus L.

    2000-07-01

    Magnetic resonance is the most powerful analytical tool used by chemists today. Its applications range from determining structures of large biomolecules to imaging of human brains. Nevertheless, magnetic resonance remains a relatively young field, in which many techniques are currently being developed that have broad applications. In this dissertation, two new techniques are presented, one that enables the determination of torsion angles in solid-state peptides and proteins, and another that involves imaging of heterogenous materials at ultra-low magnetic fields. In addition, structural studies of the prion protein via solid-state NMR are described. More specifically, work is presented in which themore » dependence of chemical shifts on local molecular structure is used to predict chemical shift tensors in solid-state peptides with theoretical ab initio surfaces. These predictions are then used to determine the backbone dihedral angles in peptides. This method utilizes the theoretical chemicalshift tensors and experimentally determined chemical-shift anisotropies (CSAs) to predict the backbone and side chain torsion angles in alanine, leucine, and valine residues. Additionally, structural studies of prion protein fragments are described in which conformationally-dependent chemical-shift measurements were made to gain insight into the structural differences between the various conformational states of the prion protein. These studies are of biological and pathological interest since conformational changes in the prion protein are believed to cause prion diseases. Finally, an ultra-low field magnetic resonance imaging technique is described that enables imaging and characterization of heterogeneous and porous media. The notion of imaging gases at ultra-low fields would appear to be very difficult due to the prohibitively low polarization and spin densities as well as the low sensitivities of conventional Faraday coil detectors. However, Chapter 5 describes how gas imaging at ultra-low fields is realized by incorporating the high sensitivities of a dc superconducting quantum interference device (SQUID) with the high polarizations attainable through optica11y pumping 129Xe gas.« less

  1. Architecture and method for a burst buffer using flash technology

    DOEpatents

    Tzelnic, Percy; Faibish, Sorin; Gupta, Uday K.; Bent, John; Grider, Gary Alan; Chen, Hsing-bung

    2016-03-15

    A parallel supercomputing cluster includes compute nodes interconnected in a mesh of data links for executing an MPI job, and solid-state storage nodes each linked to a respective group of the compute nodes for receiving checkpoint data from the respective compute nodes, and magnetic disk storage linked to each of the solid-state storage nodes for asynchronous migration of the checkpoint data from the solid-state storage nodes to the magnetic disk storage. Each solid-state storage node presents a file system interface to the MPI job, and multiple MPI processes of the MPI job write the checkpoint data to a shared file in the solid-state storage in a strided fashion, and the solid-state storage node asynchronously migrates the checkpoint data from the shared file in the solid-state storage to the magnetic disk storage and writes the checkpoint data to the magnetic disk storage in a sequential fashion.

  2. Performance and Cost Evaluation of Cryogenic Solid Propulsion Systems

    NASA Astrophysics Data System (ADS)

    Adirim, Harry; Lo, Roger; Knecht, Thomas; Reinbold, Georg-Friedrich; Poller, Sascha

    2002-01-01

    Under the sponsorship of the German Aerospace Center DLR, Cryogenic Solid Propulsion (CSP) is now in its 6th year of R&D. The development proceeds as a joint international university-, small business-, space industry- and professional research effort (Berlin University of Technology / AI: Aerospace Institute, Berlin / Bauman Moscow State Technical University, Russia / ASTRIUM GmbH, Bremen / Fraunhofer Institute for Chemical Technology, Berghausen). This paper aims at introducing CSP as a novel type of chemical propellant that uses frozen liquids as Oxygen (SOX) or Hydrogen Peroxide (SH2O2) inside of a coherent solid Hydrocarbon (PE, PU or HTPB) matrix in solid rocket motors. Theoretically any conceivable chemical rocket propellant combination (including any environmentally benign ,,green propellant") can be used in solid rocket propellant motors if the definition of solids is not restricted to "solid at ambient temperature". The CSP concept includes all suitable high energy propellant combinations, but is not limited to them. Any liquid or hybrid bipropellant combination is (Isp-wise) superior to any conventional solid propellant formulation. While CSPs do share some of the disadvantages of solid propulsion (e.g. lack of cooling fluid and preset thrust-time function), they definitely share one of their most attractive advantages: the low number of components that is the base for high reliability and low cost of structures. In this respect, CSPs are superior to liquid propellant rocket motors with whom, they share the high Isp performance. High performance, low cost, low pollution CSP technology could bring about a near term improvement for chemical Earth-to-orbit high thrust propulsion. In the long run it could surpass conventional chemical propulsion because it is better suited for applying High Energy Density Matter (HEDM) than any other mode of propulsion. So far, ongoing preliminary analyses have not shown any insuperable problems in areas of concern, such as cooling equipment and its operation during fabrication and launch, neither were there problems with thrust to weight ratio of un-cooled but insulated Cryogenic Solid Motors which ascend into their trajectory while leaving the cooling equipment at the launch pad. In performance calculations for new launchers with CSP-replacements of boosters or existing stages, ARIANE 5 and a 3-stage launcher with CSP - 1st stage into GTO serve as examples. For keeping payload-capacity in the reference orbit constant, the modeling of a rocket system essentially requires a process of iteration, in which the propellant mass is varied as central parameter and - with the help of a CSP mass-model - all other dimensions of the booster are derived from mass models etc. accordingly. The process is repeated until the payload resulting from GTO track-optimization corresponds with that of the model ARIANE 5 in sufficient approximation. Under the assumptions made, the application of cryogenic motors lead to a clear reduction of the launch mass. This is essentially caused by the lower propellant mass and secondary by the reduced structure mass. Finally cost calculations have been made by ASTRIUM and demonstrated the cost saving potential of CSP propulsion. For estimating development, production, ground facilities, and operating cost, the parametric cost modeling tool has been used in combination with Cost Estimating Relationships (CER). Parametric cost models only allow comparative analyses, therefore ARIANE 5 in its current (P1) configuration has been estimated using the same mission model as for the CSP launcher. As conclusion of these cost assessment can be stated, that the utilization of cryogenic solid propulsion could offer a considerable cost savings potential. Academic and industrial cooperation is crucial for the challenging R&D work required. It will take the combined capacities of all experts involved to unlock the promises of clean, high Isp CSP propulsion for chemical Earth-to-orbit transportation in next 10 to 15 years to come.

  3. Influencing factors and kinetics analysis on the leaching of iron from boron carbide waste-scrap with ultrasound-assisted method.

    PubMed

    Li, Xin; Xing, Pengfei; Du, Xinghong; Gao, Shuaibo; Chen, Chen

    2017-09-01

    In this paper, the ultrasound-assisted leaching of iron from boron carbide waste-scrap was investigated and the optimization of different influencing factors had also been performed. The factors investigated were acid concentration, liquid-solid ratio, leaching temperature, ultrasonic power and frequency. The leaching of iron with conventional method at various temperatures was also performed. The results show the maximum iron leaching ratios are 87.4%, 94.5% for 80min-leaching with conventional method and 50min-leaching with ultrasound assistance, respectively. The leaching of waste-scrap with conventional method fits the chemical reaction-controlled model. The leaching with ultrasound assistance fits chemical reaction-controlled model, diffusion-controlled model for the first stage and second stage, respectively. The assistance of ultrasound can greatly improve the iron leaching ratio, accelerate the leaching rate, shorten leaching time and lower the residual iron, comparing with conventional method. The advantages of ultrasound-assisted leaching were also confirmed by the SEM-EDS analysis and elemental analysis of the raw material and leached solid samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Measurement of polychlorinated biphenyls in solid waste such as transformer insulation paper by supercritical fluid extraction and gas chromatography electron capture detection.

    PubMed

    Chikushi, Hiroaki; Fujii, Yuka; Toda, Kei

    2012-09-21

    In this work, a method for measuring polychlorinated biphenyls (PCBs) in contaminated solid waste was investigated. This waste includes paper that is used in electric transformers to insulate electric components. The PCBs in paper sample were extracted by supercritical fluid extraction and analyzed by gas chromatography-electron capture detection. The recoveries with this method (84-101%) were much higher than those with conventional water extraction (0.08-14%), and were comparable to those with conventional organic solvent extraction. Limit of detection was 0.0074 mg kg(-1) and measurable up to 2.5 mg kg(-1) for 0.5 g of paper sample. Data for real insulation paper by the proposed method agreed well with those by the conventional organic solvent extraction. Extraction from wood and concrete was also investigated and good performance was obtained as well as for paper samples. The supercritical fluid extraction is simpler, faster, and greener than conventional organic solvent extraction. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Modeling and testing of a tube-in-tube separation mechanism of bodies in space

    NASA Astrophysics Data System (ADS)

    Michaels, Dan; Gany, Alon

    2016-12-01

    A tube-in-tube concept for separation of bodies in space was investigated theoretically and experimentally. The separation system is based on generation of high pressure gas by combustion of solid propellant and restricting the expansion of the gas only by ejecting the two bodies in opposite directions, in such a fashion that maximizes generated impulse. An interior ballistics model was developed in order to investigate the potential benefits of the separation system for a large range of space body masses and for different design parameters such as geometry and propellant. The model takes into account solid propellant combustion, heat losses, and gas phase chemical reactions. The model shows that for large bodies (above 100 kg) and typical separation velocities of 5 m/s, the proposed separation mechanism may be characterized by a specific impulse of 25,000 s, two order of magnitude larger than that of conventional solid rockets. It means that the proposed separation system requires only 1% of the propellant mass that would be needed for a conventional rocket for the same mission. Since many existing launch vehicles obtain such separation velocities by using conventional solid rocket motors (retro-rockets), the implementation of the new separation system design can reduce dramatically the mass of the separation system and increase safety. A dedicated experimental setup was built in order to demonstrate the concept and validate the model. The experimental results revealed specific impulse values of up to 27,000 s and showed good correspondence with the model.

  6. Solid state division progress report, period ending February 29, 1980

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1980-09-01

    Research is reported concerning theoretical solid state physics; surface and near-surface properties of solids; defects in solids; transport properties of solids; neutron scattering; crystal growth and characterization; and isotope research materials.

  7. Vectorized magnetometer for space applications using electrical readout of atomic scale defects in silicon carbide

    NASA Astrophysics Data System (ADS)

    Cochrane, Corey J.; Blacksberg, Jordana; Anders, Mark A.; Lenahan, Patrick M.

    2016-11-01

    Magnetometers are essential for scientific investigation of planetary bodies and are therefore ubiquitous on missions in space. Fluxgate and optically pumped atomic gas based magnetometers are typically flown because of their proven performance, reliability, and ability to adhere to the strict requirements associated with space missions. However, their complexity, size, and cost prevent their applicability in smaller missions involving cubesats. Conventional solid-state based magnetometers pose a viable solution, though many are prone to radiation damage and plagued with temperature instabilities. In this work, we report on the development of a new self-calibrating, solid-state based magnetometer which measures magnetic field induced changes in current within a SiC pn junction caused by the interaction of external magnetic fields with the atomic scale defects intrinsic to the semiconductor. Unlike heritage designs, the magnetometer does not require inductive sensing elements, high frequency radio, and/or optical circuitry and can be made significantly more compact and lightweight, thus enabling missions leveraging swarms of cubesats capable of science returns not possible with a single large-scale satellite. Additionally, the robustness of the SiC semiconductor allows for operation in extreme conditions such as the hot Venusian surface and the high radiation environment of the Jovian system.

  8. Neutron detection with plastic scintillators coupled to solid state photomultiplier detectors

    NASA Astrophysics Data System (ADS)

    Christian, James F.; Johnson, Erik B.; Fernandez, Daniel E.; Vogel, Samuel; Frank, Rebecca; Stoddard, Graham; Stapels, Christopher; Pereira, Jorge; Zegers, Remco

    2017-09-01

    The recent reduction of dark current in Silicon Solid-state photomultipliers (SiSSPMs) makes them an attractive alternative to conventional photomultiplier tubes (PMTs) for scintillation detection applications. Nuclear Physics experiments often require large detector volumes made using scintillation materials, which require sensitive photodetectors, such as a PMTs. PMTs add to the size, fragility, and high-voltage requirements as well as distance requirements for experiments using magnetic fields. This work compares RMD's latest detector modules, denoted as the "year 2 prototype", of plastic scintillators that discriminate gamma and high-energy particle events from neutron events using pulse shape discrimination (PSD) coupled to a SiSSPM to the following two detector modules: a similar "year 1 prototype" and a scintillator coupled to a PMT module. It characterizes the noise floor, relative signal-to-noise ratio (SNR), the timing performance, the PSD figure-of-merit (FOM) and the neutron detection efficiency of RMD's detectors. This work also evaluates the scaling of SiSSPM detector modules to accommodate the volumes needed for many Nuclear Physics experiments. The Si SSPM detector module provides a clear advantage in Nuclear Physics experiments that require the following attributes: discrimination of neutron and gamma-ray events, operation in or near strong magnetic fields, and segmentation of the detector.

  9. The use of carbon black-TiO2 composite prepared using solid state method as counter electrode and E. conferta as sensitizer for dye-sensitized solar cell (DSSC) applications

    NASA Astrophysics Data System (ADS)

    Jaafar, Hidayani; Ahmad, Zainal Arifin; Ain, Mohd Fadzil

    2018-05-01

    In this paper, counter electrodes based on carbon black (CB)-TiO2 composite are proposed as a cost-effective alternative to conventional Pt counter electrodes used in dye-sensitized solar cell (DSSC) applications. CB-TiO2 composite counter electrodes with different weight percentages of CB were prepared using the solid state method and coated onto fluorine-doped tin oxide (FTO) glass using doctor blade method while Eleiodoxa conferta (E. conferta) and Nb-doped TiO2 were used as sensitizer and photoanode, respectively, with electrolyte containing I-/I-3 redox couple. The experimental results revealed that the CB-TiO2 composite influenced the photovoltaic performance by enhancing the electrocatalytic activity. As the amount of CB increased, the catalytic activity improved due to the increase in surface area which then led to low charge-transfer resistance (RCT) at the electrolyte/CB electrode interface. Due to the use of the modified photoanode together with natural dye sensitizers, the counter electrode based on 15 wt% CB-TiO2 composite was able to produce the highest energy conversion efficiency (2.5%) making it a viable alternative counter electrode.

  10. Vectorized magnetometer for space applications using electrical readout of atomic scale defects in silicon carbide

    PubMed Central

    Cochrane, Corey J.; Blacksberg, Jordana; Anders, Mark A.; Lenahan, Patrick M.

    2016-01-01

    Magnetometers are essential for scientific investigation of planetary bodies and are therefore ubiquitous on missions in space. Fluxgate and optically pumped atomic gas based magnetometers are typically flown because of their proven performance, reliability, and ability to adhere to the strict requirements associated with space missions. However, their complexity, size, and cost prevent their applicability in smaller missions involving cubesats. Conventional solid-state based magnetometers pose a viable solution, though many are prone to radiation damage and plagued with temperature instabilities. In this work, we report on the development of a new self-calibrating, solid-state based magnetometer which measures magnetic field induced changes in current within a SiC pn junction caused by the interaction of external magnetic fields with the atomic scale defects intrinsic to the semiconductor. Unlike heritage designs, the magnetometer does not require inductive sensing elements, high frequency radio, and/or optical circuitry and can be made significantly more compact and lightweight, thus enabling missions leveraging swarms of cubesats capable of science returns not possible with a single large-scale satellite. Additionally, the robustness of the SiC semiconductor allows for operation in extreme conditions such as the hot Venusian surface and the high radiation environment of the Jovian system. PMID:27892524

  11. Vectorized magnetometer for space applications using electrical readout of atomic scale defects in silicon carbide.

    PubMed

    Cochrane, Corey J; Blacksberg, Jordana; Anders, Mark A; Lenahan, Patrick M

    2016-11-28

    Magnetometers are essential for scientific investigation of planetary bodies and are therefore ubiquitous on missions in space. Fluxgate and optically pumped atomic gas based magnetometers are typically flown because of their proven performance, reliability, and ability to adhere to the strict requirements associated with space missions. However, their complexity, size, and cost prevent their applicability in smaller missions involving cubesats. Conventional solid-state based magnetometers pose a viable solution, though many are prone to radiation damage and plagued with temperature instabilities. In this work, we report on the development of a new self-calibrating, solid-state based magnetometer which measures magnetic field induced changes in current within a SiC pn junction caused by the interaction of external magnetic fields with the atomic scale defects intrinsic to the semiconductor. Unlike heritage designs, the magnetometer does not require inductive sensing elements, high frequency radio, and/or optical circuitry and can be made significantly more compact and lightweight, thus enabling missions leveraging swarms of cubesats capable of science returns not possible with a single large-scale satellite. Additionally, the robustness of the SiC semiconductor allows for operation in extreme conditions such as the hot Venusian surface and the high radiation environment of the Jovian system.

  12. Polymorph-Dependent Green, Yellow, and Red Emissions of Organic Crystals for Laser Applications.

    PubMed

    Xu, Zhenzhen; Zhang, Zhiwei; Jin, Xue; Liao, Qing; Fu, Hongbing

    2017-12-05

    Color tuning of organic solid-state luminescent materials remains difficult and time-consuming through conventional chemical synthesis. Herein, we reported highly efficient polymorph-dependent green (P1), yellow (P2), and red (P3) emissions of organic crystals made by the same molecular building blocks of 4-(2-{4-[2-(4-diphenylamino-phenyl)-vinyl]-phenyl}-vinyl)-benzonitrile (DOPVB). Single-crystal X-ray diffraction (XRD) and spectroscopic data reveal that all three polymorphs follow the herringbone packing motif in H-type aggregations. On the one hand, from P1, P2 to P3, the reduced pitch translation along π stacks increases the intermolecular interactions between adjacent molecules, therefore leading to gradually red-shifted emissions from 540, 570 to 614 nm. On the other hand, the edge-to-face arrangement and large roll translations avoid strong π-π overlap, making P1, P2 and P3 highly emissive with record-high solid-state fluorescence quantum yields of 0.60, 0.98, and 0.68, respectively. Furthermore, the optically allowed 0-1 transitions of herringbone H-aggregates of P1, P2 and P3 naturally provide a four-level scheme, enabling green and yellow amplified spontaneous emissions (ASE) with very low thresholds. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Effect of Gallium Substitution on Lithium-Ion Conductivity and Phase Evolution in Sputtered Li7-3 xGa xLa3Zr2O12 Thin Films.

    PubMed

    Rawlence, M; Filippin, A N; Wäckerlin, A; Lin, T-Y; Cuervo-Reyes, E; Remhof, A; Battaglia, C; Rupp, J L M; Buecheler, S

    2018-04-25

    Replacing the liquid electrolyte in conventional lithium-ion batteries with thin-film solid-state lithium-ion conductors is a promising approach for increasing energy density, lifetime, and safety. In particular, Li 7 La 3 Zr 2 O 12 is appealing due to its high lithium-ion conductivity and wide electrochemical stability window. Further insights into thin-film processing of this material are required for its successful integration into solid-state batteries. In this work, we investigate the phase evolution of Li 7-3 x Ga x La 3 Zr 2 O 12 in thin films with various amounts of Li and Ga for stabilizing the cubic phase. Through this work, we gain valuable insights into the crystallization processes unique to thin films and are able to form dense Li 7-3 x Ga x La 3 Zr 2 O 12 layers stabilized in the cubic phase with high in-plane lithium-ion conductivities of up to 1.6 × 10 -5 S cm -1 at 30 °C. We also note the formation of cubic Li 7 La 3 Zr 2 O 12 at the relatively low temperature of 500 °C.

  14. Production of versatile peroxidase from Pleurotus eryngii by solid-state fermentation using agricultural residues and evaluation of its catalytic properties.

    PubMed

    Palma, C; Lloret, L; Sepúlveda, L; Contreras, E

    2016-01-01

    Interest in production of ligninolytic enzymes has been growing over recent years for their use in various applications such as recalcitrant pollutants bioremediation; specifically, versatile peroxidase (VP) presents a great potential due to its catalytic versatility. The proper selection of the fermentation mode and the culture medium should be an imperative to ensure a successful production by an economic and available medium that favors the process viability. VP was produced by solid-state fermentation (SSF) of Pleurotus eryngii, using the agricultural residue banana peel as growth medium; an enzymatic activity of 10,800 U L(-1) (36 U g(-1) of substrate) was detected after 18 days, whereas only 1800 U L(-1) was reached by conventional submerged fermentation (SF) with glucose-based medium. The kinetic parameters were determined by evaluating the H2O2 and Mn(2+) concentration effects on the Mn(3+)-tartrate complex formation. The results indicated that although the H2O2 inhibitory effect was observed for the enzyme produced by both media, the reaction rates for VP obtained by SSF were less impacted. This outcome suggests the presence of substances released from banana peel during the fermentation, which might exhibit a protective effect resulting in an improved kinetic behavior of the enzyme.

  15. Study of Hydrogen Production Method using Latent Heat of Liquefied Natural Gas

    NASA Astrophysics Data System (ADS)

    Ogawa, Masaru; Seki, Tatsuyoshi; Honda, Hiroshi; Nakamura, Motomu; Takatani, Yoshiaki

    In recent years, Fuel Cell Electrical Vehicle is expected to improve urban environment. Particularly a hydrogen fuel type FCEV expected for urban use, because its excellent characters such as short startup time, high responsibility and zero emission. On the other hand, as far as hydrogen production is concerned, large amount of CO2 is exhausted into the atmosphere by the process of LNG reforming. In our research, we studied the utilization of LNG latent heat for hydrogen gas production process as well as liquefied hydrogen process. Furthermore, CO2---Capturing as liquid state or solid state from hydrogen gas production process by LNG is also studied. Results of research shows that LNG latent heat is very effect to cool hydrogen gas for conventional hydrogen liquefied process. However, the LNG latent heat is not available for LNG reforming process. If we want to use LNG latent heat for this process, we have to develop new hydrogen gas produce process. In this new method, both hydrogen and CO2 is cooled by LNG directly, and CO2 is removed from the reforming gas. In order to make this method practical, we should develop a new type heat-exchanger to prevent solid CO2 from interfering the performance of it.

  16. Investigation of the processing conditions for the synthesis of rod-shaped LiCoO2

    NASA Astrophysics Data System (ADS)

    Kim, Taejoong; Kim, Yongseon

    2018-07-01

    We investigate the processing conditions for the synthesis of rod-shaped LiCoO2 (LCO) by a solid-state calcination of a precursor material which was prepared by a hydrothermal method. The rod-like morphology appeared to be easily broken due to the growth of primary crystals recrystallized during the calcination process. Therefore, it is crucial to maintain the temperature under a certain limit. However, the temperature must be high enough to obtain proper crystallinity of the LCO, ideally above 800 °C. Thus, we determined the optimal calcination temperature condition from the common range of temperatures that satisfies both these limiting conditions. The precursor with average diameter of 1 µm sustained the rod shape at calcination temperatures of up to 900 °C; therefore, the optimum calcination temperature could be determined between 800 and 900 °C. Whereas, a proper calcination temperature could not be found for the precursor with 500 nm of diameter because the rod shape did not maintain even at 700 °C. Thus, the maximum temperature at which the rod shape is retained decreases with smaller diameter of the precursor rods, indicating adjusting the diameter above a limiting value is necessary to prepare LCO rod by conventional solid state calcination.

  17. Thermal management of LEDs: package to system

    NASA Astrophysics Data System (ADS)

    Arik, Mehmet; Becker, Charles A.; Weaver, Stanton E.; Petroski, James

    2004-01-01

    Light emitting diodes, LEDs, historically have been used for indicators and produced low amounts of heat. The introduction of high brightness LEDs with white light and monochromatic colors have led to a movement towards general illumination. The increased electrical currents used to drive the LEDs have focused more attention on the thermal paths in the developments of LED power packaging. The luminous efficiency of LEDs is soon expected to reach over 80 lumens/W, this is approximately 6 times the efficiency of a conventional incandescent tungsten bulb. Thermal management for the solid-state lighting applications is a key design parameter for both package and system level. Package and system level thermal management is discussed in separate sections. Effect of chip packages on junction to board thermal resistance was compared for both SiC and Sapphire chips. The higher thermal conductivity of the SiC chip provided about 2 times better thermal performance than the latter, while the under-filled Sapphire chip package can only catch the SiC chip performance. Later, system level thermal management was studied based on established numerical models for a conceptual solid-state lighting system. A conceptual LED illumination system was chosen and CFD models were created to determine the availability and limitations of passive air-cooling.

  18. Micro/Nano Fabricated Solid-State Thermoelectric Generator Devices for Integrated High Voltage Power Sources

    NASA Astrophysics Data System (ADS)

    Fleurial, J.-P.; Ryan, M. A.; Snyder, G. J.; Huang, C.-K.; Whitacre, J. F.; Patel, J.; Lim, J.; Borshchevsky, A.

    2002-01-01

    Deep space missions have a strong need for compact, high power density, reliable and long life electrical power generation and storage under extreme temperature conditions. Except for electrochemical batteries and solar cells, there are currently no available miniaturized power sources. Conventional power generators devices become inefficient in extreme environments (such as encountered in Mars, Venus or outer planet missions) and rechargeable energy storage devices can only be operated in a narrow temperature range thereby limiting mission duration. The planned development of much smaller spacecrafts incorporating a variety of micro/nanodevices and miniature vehicles will require novel, reliable power technologies. It is also expected that such micro power sources could have a wide range of terrestrial applications, in particular when the limited lifetime and environmental limitations of batteries are key factors. Advanced solid-state thermoelectric combined with radioisotope or waste heat sources and low profile energy storage devices are ideally suited for these applications. The Jet Propulsion Laboratory has been actively pursuing the development of thermoelectric micro/nanodevices that can be fabricated using a combination of electrochemical deposition and integrated circuit processing techniques. Some of the technical challenges associated with these micro/nanodevice concepts, their expected level of performance and experimental fabrication and testing results to date are presented and discussed.

  19. Study of magnetic behavior in hexagonal-YMn1-xFexO3 (x=0 and 0.2) nanoparticles using remanent magnetization curves

    NASA Astrophysics Data System (ADS)

    Chauhan, Samta; Singh, Amit Kumar; Srivastava, Saurabh Kumar; Chandra, Ramesh

    2016-09-01

    We have studied the magnetic behavior of YMn1-xFexO3 (x=0 and 0.2) nanoparticles synthesized by conventional solid state reaction method. The as-synthesized nanoparticles were found to have hexagonal phase with P63cm space group confirmed by X-Ray diffraction. The particle size was found to be ~70 nm as confirmed by both X-Ray diffraction and Transmission Electron Microscopy. DC magnetization and memory effect measurements imply that the h-YMnO3 nanoparticles bear a resemblance to super spin-glass state following de Almeida-Thouless like behavior which is being suppressed by Fe-doping. The Fe-doping in YMnO3 enhances the antiferromagnetic (AFM) transition temperature TN to ~79 K and induces a new magnetic state due to the surface spins which is realized as diluted antiferromagnet in a field (DAFF) as explored by the thermoremanent and isothermoremanent magnetization measured with different applied magnetic field.

  20. Solid-state modeling of the terahertz spectrum of the high explosive HMX.

    PubMed

    Allis, Damian G; Prokhorova, Darya A; Korter, Timothy M

    2006-02-09

    The experimental solid-state terahertz (THz) spectrum (3-120 cm(-1)) of the beta-crystal form of the high explosive octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) has been analyzed using solid-state density functional theory calculations. Various density functionals (both generalized gradient approximation and local density approximation) are compared in terms of their abilities to reproduce the experimentally observed solid-state structure and low-frequency vibrational motions. Good-to-excellent agreement between solid-state theory and experiment can be achieved in the THz region where isolated-molecule calculations fail to reproduce the observed spectral features, demonstrating a clear limitation of using isolated-molecule calculations for the assignment of THz frequency motions in molecular solids. The deficiency of isolated-molecule calculations is traced to modification of the molecular structure in the solid state through crystal packing effects and the formation of weak C-H...O hydrogen bonds.

  1. Case Study for the ARRA-funded Ground Source Heat Pump (GSHP) Demonstration at Wilders Grove Solid Waste Service Center in Raleigh, NC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Xiaobing; Malhotra, Mini; Xiong, Zeyu

    High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights the findings of a case study of one of the ARRA-funded GSHP demonstration projects, a distributed GSHP system for providing all the space conditioning, outdoor air ventilation, and 100% domestic hot water tomore » the Wilders Grove Solid Waste Service Center of City of Raleigh, North Carolina. This case study is based on the analysis of measured performance data, construction costs, and simulations of the energy consumption of conventional central heating, ventilation, and air-conditioning (HVAC) systems providing the same level of space conditioning and outdoor air ventilation as the demonstrated GSHP system. The evaluated performance metrics include the energy efficiency of the heat pump equipment and the overall GSHP system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of the GSHP system compared with conventional HVAC systems. This case study also identified opportunities for reducing uncertainties in the performance evaluation and improving the operational efficiency of the demonstrated GSHP system.« less

  2. Optofluidic devices with integrated solid-state nanopores

    PubMed Central

    Hawkins, Aaron R.; Schmidt, Holger

    2016-01-01

    This review (with 90 refs.) covers the state of the art in optofluidic devices with integrated solid-state nanopores for use in detection and sensing. Following an introduction into principles of optofluidics and solid-state nanopore technology, we discuss features of solid-state nanopore based assays using optofluidics. This includes the incorporation of solid-state nanopores into optofluidic platforms based on liquid-core anti-resonant reflecting optical waveguides (ARROWs), methods for their fabrication, aspects of single particle detection and particle manipulation. We then describe the new functionalities provided by solid-state nanopores integrated into optofluidic chips, in particular acting as smart gates for correlated electro-optical detection and discrimination of nanoparticles. This enables the identification of viruses and λ-DNA, particle trajectory simulations, enhancing sensitivity by tuning the shape of nanopores. The review concludes with a summary and an outlook. PMID:27046940

  3. Infiltrated La0.4Sr0.4Fe0.03Ni0.03Ti0.94O3 based anodes for all ceramic and metal supported solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Nielsen, Jimmi; Persson, Åsa H.; Sudireddy, Bhaskar R.; Irvine, John T. S.; Thydén, Karl

    2017-12-01

    For improved robustness, durability and to avoid severe processing challenges alternatives to the Ni:YSZ composite electrode is highly desirable. The Ni:YSZ composite electrode is conventionally used for solid oxide fuel cell and solid oxide electrolysis cell. In the present study we report on high performing nanostructured Ni:CGO electrocatalyst coated A site deficient Lanthanum doped Strontium Titanate (La0.4Sr0.4Fe0.03Ni0.03Ti0.94O3) based anodes. The anodes were incorporated into the co-sintered DTU metal supported solid oxide fuel cell design and large sized 12 cm × 12 cm cells were fabricated. The titanate material showed good processing characteristics and surface wetting properties towards the Ni:CGO electrocatalyst coating. The cell performances were evaluated on single cell level (active area 16 cm2) and a power density at 0.7 V and 700 °C of 0.650 Wcm-2 with a fuel utilization of 31% was achieved. Taking the temperature into account the performances of the studied anodes are among the best reported for redox stable and corrosion resistant alternatives to the conventional Ni:YSZ composite solid oxide cell electrode.

  4. Energy efficiency buildings program

    NASA Astrophysics Data System (ADS)

    1981-05-01

    Progress is reported in developing techniques for auditing the energy performance of buildings. The ventilation of buildings and indoor air quality is discussed from the viewpoint of (1) combustion generated pollutants; (2) organic contaminants; (3) radon emanation, measurements, and control; (4) strategies for the field monitoring of indoor air quality; and (5) mechanical ventilation systems using air-to-air heat exchanges. The development of energy efficient windows to provide optimum daylight with minimal thermal losses in cold weather and minimum thermal gain in hot weather is considered as well as the production of high frequency solid state ballasts for fluorescent lights to provide more efficient lighting at a 25% savings over conventional core ballasts. Data compilation, analysis, and demonstration activities are summarized.

  5. Lattice vibrations boost demagnetization entropy in a shape-memory alloy

    NASA Astrophysics Data System (ADS)

    Stonaha, P. J.; Manley, M. E.; Bruno, N. M.; Karaman, I.; Arroyave, R.; Singh, N.; Abernathy, D. L.; Chi, S.

    2015-10-01

    Magnetocaloric (MC) materials present an avenue for chemical-free, solid-state refrigeration through cooling via adiabatic demagnetization. We have used inelastic neutron scattering to measure the lattice dynamics in the MC material N i45C o5M n36.6I n13.4 . Upon heating across the Curie temperature (TC) , the material exhibits an anomalous increase in phonon entropy of 0.22 ±0.04 kB/atom , which is ten times larger than expected from conventional thermal expansion. This transition is accompanied by an abrupt softening of the transverse optic phonon. We present first-principles calculations showing a strong coupling between lattice distortions and magnetic excitations.

  6. Fishing the Fermi sea

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Canfield, P.

    2008-03-01

    Sophocles had it right, the Rolling Stones made a friendly amendment and Linus Pauling detailed the conceptual mechanism for finding novel materials that will define and revolutionize the future. Within the field of solid-state physics, the discovery of remarkable phases and transitions is often tightly coupled to the design, discovery and growth of novel materials. The past several decades of work in the field of correlated electron physics - that is, the study of materials in which the interactions are sufficiently strong that conventional single-electron theories don't apply - can be described by a list of materials that have definedmore » new extremes, be it extremes of temperature, field, pressure, complexity or, even better, simplicity.« less

  7. Iodine-stabilized single-frequency green InGaN diode laser.

    PubMed

    Chen, Yi-Hsi; Lin, Wei-Chen; Shy, Jow-Tsong; Chui, Hsiang-Chen

    2018-01-01

    A 520-nm InGaN diode laser can emit a milliwatt-level, single-frequency laser beam when the applied current slightly exceeds the lasing threshold. The laser frequency was less sensitive to diode temperature and could be finely tuned by adjusting the applied current. Laser frequency was stabilized onto a hyperfine component in an iodine transition through the saturated absorption spectroscopy. The uncertainty of frequency stabilization was approximately 8×10 -9 at a 10-s integration time. This compact laser system can replace the conventional green diode-pumped solid-state laser and applied as a frequency reference. A single longitudinal mode operational region with diode temperature, current, and output power was investigated.

  8. Cell Concepts of Metal-Sulfur Batteries (Metal = Li, Na, K, Mg): Strategies for Using Sulfur in Energy Storage Applications.

    PubMed

    Medenbach, Lukas; Adelhelm, Philipp

    2017-09-29

    There is great interest in using sulfur as active component in rechargeable batteries thanks to its low cost and high specific charge (1672 mAh/g). The electrochemistry of sulfur, however, is complex and cell concepts are required, which differ from conventional designs. This review summarizes different strategies for utilizing sulfur in rechargeable batteries among membrane concepts, polysulfide concepts, all-solid-state concepts as well as high-temperature systems. Among the more popular lithium-sulfur and sodium-sulfur batteries, we also comment on recent results on potassium-sulfur and magnesium-sulfur batteries. Moreover, specific properties related to the type of light metal are discussed.

  9. Heat storage in alloy transformations

    NASA Technical Reports Server (NTRS)

    Birchenall, C. E.

    1980-01-01

    Heats of transformation of eutectic alloys were measured for many binary and ternary systems by differential scanning calorimetry and thermal analysis. Only the relatively cheap and plentiful elements Mg, Al, Si, P, Ca, Cu, Zn were considered. A method for measuring volume change during transformation was developed using x-ray absorption in a confined sample. Thermal expansion coefficients of both solid and liquid states of aluminum and of its eutectics with copper and with silicon also were determined. Preliminary evaluation of containment materials lead to the selection of silicon carbide as the initial material for study. Possible applications of alloy PCMs for heat storage in conventional and solar central power stations, small solar receivers and industrial furnace operations are under consideration.

  10. Thin-film diffusion brazing of titanium alloys

    NASA Technical Reports Server (NTRS)

    Mikus, E. B.

    1972-01-01

    A thin film diffusion brazing technique for joining titanium alloys by use of a Cu intermediate is described. The method has been characterized in terms of static and dynamic mechanical properties on Ti-6Al-4V alloy. These include tensile, fracture toughness, stress corrosion, shear, corrosion fatigue, mechanical fatigue and acoustic fatigue. Most of the properties of titanium joints formed by thin film diffusion brazing are equal or exceed base metal properties. The advantages of thin film diffusion brazing over solid state diffusion bonding and brazing with conventional braze alloys are discussed. The producibility advantages of this process over others provide the potential for producing high efficiency joints in structural components of titanium alloys for the minimum cost.

  11. Electroluminescence of ordered ZnO nanorod array/p-GaN light-emitting diodes with graphene current spreading layer

    PubMed Central

    2014-01-01

    Ordered ZnO nanorod array/p-GaN heterojunction light-emitting diodes (LEDs) have been fabricated by introducing graphene as the current spreading layer, which exhibit improved electroluminescence performance by comparison to the LED using a conventional structure (indium-tin-oxide as the current spreading layer). In addition, by adjusting the diameter of ZnO nanorod array in use, the light emission of the ZnO nanorod array/p-GaN heterojunction LEDs was enhanced further. This work has great potential applications in solid-state lighting, high performance optoelectronic devices, and so on. PACS 78.60.Fi; 85.60.Jb; 78.67.Lt; 81.10.Dn PMID:25489284

  12. Electroluminescence of ordered ZnO nanorod array/p-GaN light-emitting diodes with graphene current spreading layer.

    PubMed

    Dong, Jing-Jing; Hao, Hui-Ying; Xing, Jie; Fan, Zhen-Jun; Zhang, Zi-Li

    2014-01-01

    Ordered ZnO nanorod array/p-GaN heterojunction light-emitting diodes (LEDs) have been fabricated by introducing graphene as the current spreading layer, which exhibit improved electroluminescence performance by comparison to the LED using a conventional structure (indium-tin-oxide as the current spreading layer). In addition, by adjusting the diameter of ZnO nanorod array in use, the light emission of the ZnO nanorod array/p-GaN heterojunction LEDs was enhanced further. This work has great potential applications in solid-state lighting, high performance optoelectronic devices, and so on. 78.60.Fi; 85.60.Jb; 78.67.Lt; 81.10.Dn.

  13. Non-Conventional Applications of Computerized Tomography: Analysis of Solid Dosage Forms Produced by Pharmaceutical Industry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Martins de Oliveira, Jose Jr.; Germano Martins, Antonio Cesar

    X-ray computed tomography (CT) refers to the cross-sectional imaging of an object measuring the transmitted radiation at different directions. In this work, we describe a non-conventional application of computerized tomography: visualization and improvements in the understanding of some internal structural features of solid dosage forms. A micro-CT X-ray scanner, with a minimum resolution of 30 mum was used to characterize some pharmaceutical tablets, granules, controlled-release osmotic tablet and liquid-filled soft-gelatin capsules. The analysis presented in this work are essentially qualitative, but quantitative parameters, such as porosity, density distribution, tablets dimensions, etc. could also be obtained using the related CT techniques.

  14. First principles study on electrochemical and chemical stability of solid electrolyte–electrode interfaces in all-solid-state Li-ion batteries

    DOE PAGES

    Zhu, Yizhou; He, Xingfeng; Mo, Yifei

    2015-12-11

    All-solid-state Li-ion batteries based on ceramic solid electrolyte materials are a promising next-generation energy storage technology with high energy density and enhanced cycle life. The poor interfacial conductance is one of the key limitations in enabling all-solid-state Li-ion batteries. However, the origin of this poor conductance has not been understood, and there is limited knowledge about the solid electrolyte–electrode interfaces in all-solid-state Li-ion batteries. In this paper, we performed first principles calculations to evaluate the thermodynamics of the interfaces between solid electrolyte and electrode materials and to identify the chemical and electrochemical stabilities of these interfaces. Our computation results revealmore » that many solid electrolyte–electrode interfaces have limited chemical and electrochemical stability, and that the formation of interphase layers is thermodynamically favorable at these interfaces. These formed interphase layers with different properties significantly affect the electrochemical performance of all-solid-state Li-ion batteries. The mechanisms of applying interfacial coating layers to stabilize the interface and to reduce interfacial resistance are illustrated by our computation. This study demonstrates a computational scheme to evaluate the chemical and electrochemical stability of heterogeneous solid interfaces. Finally, the enhanced understanding of the interfacial phenomena provides the strategies of interface engineering to improve performances of all-solid-state Li-ion batteries.« less

  15. Processing and characterization of solid and microcellular PHBV/PBAT blend and its RWF/nanoclay composites

    Treesearch

    Alireza Javadi; Yottha Srithep; Jungjoo Lee; Srikanth Pilla; Craig Clemons; Shaoqin Gong; Lih-Sheng Turng

    2010-01-01

    Solid and microcellular components made of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/ poly (butylenes adipate-co-terephthalate) (PBAT) blend (weight ration of PHBV:PBAT = 30:70), recycled wood fiber (RWF), and nanoclay (NC) were prepared via a conventional and microcellular-injection molding process, respectively. Morphology, thermal properties, and...

  16. Light-emitting nanolattices with enhanced brightness

    NASA Astrophysics Data System (ADS)

    Ng, Ryan C.; Mandal, Rajib; Anthony, Rebecca J.; Greer, Julia R.

    2017-02-01

    Three-dimensional (3D) photonic crystals have potential in solid state lighting applications due to their advantages over conventional planar thin film devices. Periodicity in a photonic crystal structure enables engineering of the density of states to improve spontaneous light emission according to Fermi's golden rule. Unlike planar thin films, which suffer significantly from total internal reflection, a 3D architectured structure is distributed in space with many non-flat interfaces, which facilitates a substantial enhancement in light extraction. We demonstrate the fabrication of 3D nano-architectures with octahedron geometry that utilize luminescing silicon nanocrystals as active media with an aluminum cathode and indium tin oxide anode towards the realization of a 3D light emitting device. The developed fabrication procedure allows charge to pass through the nanolattice between two contacts for electroluminescence. These initial fabrication efforts suggest that 3D nano-architected devices are realizable and can reach greater efficiencies than planar devices.

  17. Temperature-dependent ac conductivity and dielectric response of vanadium doped CaCu3Ti4O12 ceramic

    NASA Astrophysics Data System (ADS)

    Sen, A.; Maiti, U. N.; Thapa, R.; Chattopadhyay, K. K.

    2011-09-01

    Successful incorporation of vanadium dopant within the giant dielectric material CaCu 3Ti 4O12 (CCTO) through a conventional solid-state sintering process is achieved and its influence on the dielectric as well as electrical properties as a function of temperature and frequency is reported here. Proper crystalline phase formation together with dopant induced lattice constant shrinkage was confirmed through X-ray diffraction. The temperature dependence of the dielectric constant at different constant frequencies was investigated. We infer that the correlated barrier hopping (CBH) model is dominant in the conduction mechanism of the ceramic as per the temperature-dependent ac conductivity measurements. The electronic parameters such as density of the states at the Fermi level, N( E f) and hopping distance, R ω of the ceramic were also calculated using this model.

  18. Solid-state rechargeable magnesium battery

    DOEpatents

    Shao, Yuyan; Liu, Jun; Liu, Tianbiao; Li, Guosheng

    2016-09-06

    Embodiments of a solid-state electrolyte comprising magnesium borohydride, polyethylene oxide, and optionally a Group IIA or transition metal oxide are disclosed. The solid-state electrolyte may be a thin film comprising a dispersion of magnesium borohydride and magnesium oxide nanoparticles in polyethylene oxide. Rechargeable magnesium batteries including the disclosed solid-state electrolyte may have a coulombic efficiency .gtoreq.95% and exhibit cycling stability for at least 50 cycles.

  19. Solid State Research, 1980:1.

    DTIC Science & Technology

    1980-02-15

    ESD-TR-79-325 H 1 Solid State Research 1980 Prepared under Electronic Systems Division Contract FI%28-80-C-0002 by Lincoln Laboratory MASSkCHIISETTS...it is no longer needed. MASSACHUSETTS IN*STITUTE OF TECHNOLOGY LINCOLN LABORATORY V SOLID STATE RESEARCH QUARTERLY TECHNICAL SUMMARY REPORT I NOVEMBER...January 1990. The topics covered a-e Solid State Device Research , Quantum Electronics, Materials Rese.rch, Microelec- tronics, and Analog Device

  20. Influence of kraft pulping on carboxylate content of softwood kraft pulps

    Treesearch

    Zheng Dang; Thomas Elder; Arthur J. Ragauskas

    2006-01-01

    This study characterizes changes in fiber charge, which is the carboxylate content of fibers, for two sets of kraft pulps: (1) conventional laboratory cooked loblolly pine kraft pulps and (2) conventional pulping (CK) versus low solids pulping (LS) pulps. Laboratory kraft pulping of loblolly pine was carried out to study the influence of pulping conditions, including...

  1. Integrated Interface Strategy toward Room Temperature Solid-State Lithium Batteries.

    PubMed

    Ju, Jiangwei; Wang, Yantao; Chen, Bingbing; Ma, Jun; Dong, Shanmu; Chai, Jingchao; Qu, Hongtao; Cui, Longfei; Wu, Xiuxiu; Cui, Guanglei

    2018-04-25

    Solid-state lithium batteries have drawn wide attention to address the safety issues of power batteries. However, the development of solid-state lithium batteries is substantially limited by the poor electrochemical performances originating from the rigid interface between solid electrodes and solid-state electrolytes. In this work, a composite of poly(vinyl carbonate) and Li 10 SnP 2 S 12 solid-state electrolyte is fabricated successfully via in situ polymerization to improve the rigid interface issues. The composite electrolyte presents a considerable room temperature conductivity of 0.2 mS cm -1 , an electrochemical window exceeding 4.5 V, and a Li + transport number of 0.6. It is demonstrated that solid-state lithium metal battery of LiFe 0.2 Mn 0.8 PO 4 (LFMP)/composite electrolyte/Li can deliver a high capacity of 130 mA h g -1 with considerable capacity retention of 88% and Coulombic efficiency of exceeding 99% after 140 cycles at the rate of 0.5 C at room temperature. The superior electrochemical performance can be ascribed to the good compatibility of the composite electrolyte with Li metal and the integrated compatible interface between solid electrodes and the composite electrolyte engineered by in situ polymerization, which leads to a significant interfacial impedance decrease from 1292 to 213 Ω cm 2 in solid-state Li-Li symmetrical cells. This work provides vital reference for improving the interface compatibility for room temperature solid-state lithium batteries.

  2. Experimental evidence for s-wave pairing symmetry in superconducting Cu(x)Bi2Se3 single crystals using a scanning tunneling microscope.

    PubMed

    Levy, Niv; Zhang, Tong; Ha, Jeonghoon; Sharifi, Fred; Talin, A Alec; Kuk, Young; Stroscio, Joseph A

    2013-03-15

    Topological superconductors represent a newly predicted phase of matter that is topologically distinct from conventional superconducting condensates of Cooper pairs. As a manifestation of their topological character, topological superconductors support solid-state realizations of Majorana fermions at their boundaries. The recently discovered superconductor Cu(x)Bi(2)Se(3) has been theoretically proposed as an odd-parity superconductor in the time-reversal-invariant topological superconductor class, and point-contact spectroscopy measurements have reported the observation of zero-bias conductance peaks corresponding to Majorana states in this material. Here we report scanning tunneling microscopy measurements of the superconducting energy gap in Cu(x)Bi(2)Se(3) as a function of spatial position and applied magnetic field. The tunneling spectrum shows that the density of states at the Fermi level is fully gapped without any in-gap states. The spectrum is well described by the Bardeen-Cooper-Schrieffer theory with a momentum independent order parameter, which suggests that Cu(x)Bi(2)Se(3) is a classical s-wave superconductor contrary to previous expectations and measurements.

  3. Modified Reference SPS with Solid State Transmitting Antenna

    NASA Technical Reports Server (NTRS)

    Woodcock, G. R.; Sperber, B. R.

    1980-01-01

    The development of solid state microwave power amplifiers for a solar power satellite transmitting antenna is discussed. State-of-the-art power-added efficiency, gain, and single device power of various microwave solid state devices are compared. The GaAs field effect transistors and the Si-bipolar transistors appear potentially feasible for solar power satellite use. The integration of solid state devices into antenna array elements is examined and issues concerning antenna integration and consequent satellite configurations are examined.

  4. Mathematical Analysis of the Solidification Behavior of Plain Steel Based on Solute- and Heat-Transfer Equations in the Liquid-Solid Zone

    NASA Astrophysics Data System (ADS)

    Fujimura, Toshio; Takeshita, Kunimasa; Suzuki, Ryosuke O.

    2018-04-01

    An analytical approximate solution to non-linear solute- and heat-transfer equations in the unsteady-state mushy zone of Fe-C plain steel has been obtained, assuming a linear relationship between the solid fraction and the temperature of the mushy zone. The heat transfer equations for both the solid and liquid zone along with the boundary conditions have been linked with the equations to solve the whole equations. The model predictions ( e.g., the solidification constants and the effective partition ratio) agree with the generally accepted values and with a separately performed numerical analysis. The solidus temperature predicted by the model is in the intermediate range of the reported formulas. The model and Neuman's solution are consistent in the low carbon range. A conventional numerical heat analysis ( i.e., an equivalent specific heat method using the solidus temperature predicted by the model) is consistent with the model predictions for Fe-C plain steels. The model presented herein simplifies the computations to solve the solute- and heat-transfer simultaneous equations while searching for a solidus temperature as a part of the solution. Thus, this model can reduce the complexity of analyses considering the heat- and solute-transfer phenomena in the mushy zone.

  5. A novel method for preparation of high dense tetragonal Li7La3Zr2O12

    NASA Astrophysics Data System (ADS)

    Zhao, Pengcheng; Wen, Yuehua; Cheng, Jie; Cao, Gaoping; Jin, Zhaoqing; Ming, Hai; Xu, Yan; Zhu, Xiayu

    2017-03-01

    For conventional preparation methods of Li7La3Zr2O12 (LLZO) solid state electrolytes, there is a stereotype that higher density always comes from higher pressure enforced upon the LLZO pellets. In this paper, a different way with an auto-consolidation mechanism is provided and discussed. No pressing operations are employed during the whole preparation process. Due to the surface tension of liquid melted Li2O at sintering temperature, LLZO particles could aggregate together freely and automatically. The preparation process for dense LLZO is greatly simplified. A dense tetragonal LLZO with high relative density about 93% has been prepared successfully by this auto-consolidation method. And there are no voids observed in the SEM images. At 30 °C, the total conductivity is about 5.67 × 10-5 S cm-1, which is the highest one for tetragonal LLZO in the reported issues, even two times higher than that prepared by hot-pressing method. The activation energy for total conductivity is ∼0.35 eV atom-1 at 30-120 °C, slightly lower than the previous reported values. This work sheds light on the understanding of the consolidation mechanism for solid electrolytes and suggests a reliable route to syhthesize cemanic solid electrolytes.

  6. Improvement of municipal wastewater pretreatment by direct membrane filtration.

    PubMed

    Nascimento, Thiago A; Mejía, Fanny R; Fdz-Polanco, Fernando; Peña Miranda, Mar

    2017-10-01

    The high content of particulate matter in municipal wastewater hinders the conventional anaerobic treatments at psychrophilic temperatures. The hydrolysis of the particulate chemical oxygen demand (pCOD) could be the limiting step under these conditions. Therefore, new pretreatments or improved conventional pretreatments are needed in order to separate pCOD. In this work, direct membrane filtration of municipal wastewater, using an ultrafiltration membrane, was investigated. This intensive pretreatment, which aims to separate soluble chemical oxygen demand (sCOD) and to concentrate pCOD, together with anaerobic treatments of both streams at psychrophilic and mesophilic conditions respectively, could be an alternative to the conventional activated sludge process. The obtained results show a removal yield of 24.9% of the total solids (TS) and 45% of total chemical oxygen demand (tCOD), obtaining a permeate free of suspended solids. This physical removal implies the accumulation of solids inside the membrane tank, reaching the values of 45.4 and 4.4 g/L of TS in the sedimentation and filtration sections, respectively. The membrane operated with filtration, backwashing cycles and continuous gas sparging, with a permeate flux predominantly around 10 L/(m 2  h). The results show the viability of the technology to concentrate pCOD and so to improve energy recovery from municipal wastewater.

  7. A solid state video recorder as a direct replacement of a mechanically driven disc recording device in a security system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Terry, P.L.

    1989-01-01

    Whether upgrading or developing a security system, investing in a solid state video recorder may prove to be quite prudent. Even though the initial cost of a solid state recorder may be more expensive, when comparing it to a disc recorder it is practically maintenance free. Thus, the cost effectiveness of a solid state video recorder over an extended period of time more than justifies the initial expense. This document illustrates the use of a solid state video recorder as a direct replacement. It replaces a mechanically driven disc recorder that existed in a synchronized video recording system. The originalmore » system was called the Universal Video Disc Recorder System. The modified system will now be referred to as the Solid State Video Recording System. 5 figs.« less

  8. Lipid immiscibility and biophysical properties: Molecular order within and among unit cell volumes

    USDA-ARS?s Scientific Manuscript database

    Saturated and unsaturated fatty acids clearly have a discrete chemical structure in the solid state. In a saturated solution, the solid state and solution state are in chemical equilibrium. The lipid stearic acid packs in unit cell volumes in the liquid state as well as in the solid state. Normal...

  9. 5.8kV SiC PiN Diode for Switching of High-Efficiency Inductive Pulsed Plasma Thruster Circuits

    NASA Technical Reports Server (NTRS)

    Toftul, Alexandra; Polzin, Kurt A.; Hudgins, Jerry L.

    2014-01-01

    Inductive Pulsed Plasma Thruster (IPPT) pulse circuits, such as those needed to operate the Pulsed Inductive Thruster (PIT), are required to quickly switch capacitor banks operating at a period of µs while conducting current at levels on the order of at least 10 kA. [1,2] For all iterations of the PIT to date, spark gaps have been used to discharge the capacitor bank through an inductive coil. Recent availability of fast, high-power solid state switching devices makes it possible to consider the use of semiconductor switches in modern IPPTs. In addition, novel pre-ionization schemes have led to a reduction in discharge energy per pulse for electric thrusters of this type, relaxing the switching requirements for these thrusters. [3,4] Solid state switches offer the advantage of greater controllability and reliability, as well as decreased drive circuit dimensions and mass relative to spark gap switches. The use of solid state devices such as Integrated Gate Bipolar Transistors (IGBTs), Gate Turn-off Thyristors (GTOs) and Silicon-Controlled Rectifiers (SCRs) often involves the use of power diodes. These semiconductor devices may be connected antiparallel to the switch for protection from reverse current, or used to reduce power loss in a circuit by clamping off current ringing. In each case, higher circuit efficiency may be achieved by using a diode that is able to transition, or 'switch,' from the forward conducting state ('on' state) to the reverse blocking state ('off' state) in the shortest amount of time, thereby minimizing current ringing and switching losses. Silicon Carbide (SiC) PiN diodes offer significant advantages to conventional fast-switching Silicon (Si) diodes for high power and fast switching applications. A wider band gap results in a breakdown voltage 10 times that of Si, so that a SiC device may have a thinner drift region for a given blocking voltage. [5] This leads to smaller, lighter devices for high voltage applications, as well as reduced forward conduction losses, faster reverse recovery time (faster turn-off), and lower-magnitude reverse recovery current. In addition, SiC devices have lower leakage current as compared to their Si counterparts, and a high thermal conductivity, potentially allowing the former to operate at higher temperatures with a smaller, lighter heatsink (or no heatsink at all).

  10. Solid-state optical refrigeration to sub-100 Kelvin regime

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Melgaard, Seth D.; Albrecht, Alexander R.; Hehlen, Markus P.

    We report that since the first demonstration of net cooling twenty years ago, optical refrigeration of solids has progressed to outperform all other solid-state cooling processes. It has become the first and only solid-state refrigerator capable of reaching cryogenic temperatures, and now the first solid-state cooling below 100 K. Such substantial progress required a multi-disciplinary approach of pump laser absorption enhancement, material characterization and purification, and thermal management. Here we present the culmination of two decades of progress, the record cooling to ≈91K from room temperature.

  11. Solid-state optical refrigeration to sub-100 Kelvin regime

    DOE PAGES

    Melgaard, Seth D.; Albrecht, Alexander R.; Hehlen, Markus P.; ...

    2016-02-05

    We report that since the first demonstration of net cooling twenty years ago, optical refrigeration of solids has progressed to outperform all other solid-state cooling processes. It has become the first and only solid-state refrigerator capable of reaching cryogenic temperatures, and now the first solid-state cooling below 100 K. Such substantial progress required a multi-disciplinary approach of pump laser absorption enhancement, material characterization and purification, and thermal management. Here we present the culmination of two decades of progress, the record cooling to ≈91K from room temperature.

  12. Solid-state optical refrigeration to sub-100 Kelvin regime

    PubMed Central

    Melgaard, Seth D.; Albrecht, Alexander R.; Hehlen, Markus P.; Sheik-Bahae, Mansoor

    2016-01-01

    Since the first demonstration of net cooling twenty years ago, optical refrigeration of solids has progressed to outperform all other solid-state cooling processes. It has become the first and only solid-state refrigerator capable of reaching cryogenic temperatures, and now the first solid-state cooling below 100 K. Such substantial progress required a multi-disciplinary approach of pump laser absorption enhancement, material characterization and purification, and thermal management. Here we present the culmination of two decades of progress, the record cooling to ≈ 91 K from room temperature. PMID:26847703

  13. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    NASA Astrophysics Data System (ADS)

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-01

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 1013 to 1015 n/cm2. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 1015 to 1016 n/cm2 with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  14. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    NASA Technical Reports Server (NTRS)

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-01

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 10(exp 13) to 10(exp 15) n per square centimeters. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 10(exp 15) to 10(exp 16) n per square centimeters with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  15. Comparison of solid-state and submerged-state fermentation for the bioprocessing of switchgrass to ethanol and acetate by Clostridium phytofermentans.

    PubMed

    Jain, Abhiney; Morlok, Charles K; Henson, J Michael

    2013-01-01

    The conversion of sustainable energy crops using microbiological fermentation to biofuels and bioproducts typically uses submerged-state processes. Alternatively, solid-state fermentation processes have several advantages when compared to the typical submerged-state processes. This study compares the use of solid-state versus submerged-state fermentation using the mesophilic anaerobic bacterium Clostridium phytofermentans in the conversion of switchgrass to the end products of ethanol, acetate, and hydrogen. A shift in the ratio of metabolic products towards more acetate and hydrogen production than ethanol production was observed when C. phytofermentans was grown under solid-state conditions as compared to submerged-state conditions. Results indicated that the end product concentrations (in millimolar) obtained using solid-state fermentation were higher than using submerged-state fermentation. In contrast, the total fermentation products (in weight of product per weight of carbohydrates consumed) and switchgrass conversion were higher for submerged-state fermentation. The conversion of xylan was greater than glucan conversion under both fermentation conditions. An initial pH of 7 and moisture content of 80 % resulted in maximum end products formation. Scanning electron microscopy study showed the presence of biofilm formed by C. phytofermentans growing on switchgrass under submerged-state fermentation whereas bacterial cells attached to surface and no apparent biofilm was observed when grown under solid-state fermentation. To our knowledge, this is the first study reporting consolidated bioprocessing of a lignocellulosic substrate by a mesophilic anaerobic bacterium under solid-state fermentation conditions.

  16. Superior Blends Solid Polymer Electrolyte with Integrated Hierarchical Architectures for All-Solid-State Lithium-Ion Batteries.

    PubMed

    Zhang, Dechao; Zhang, Long; Yang, Kun; Wang, Hongqiang; Yu, Chuang; Xu, Di; Xu, Bo; Wang, Li-Min

    2017-10-25

    Exploration of advanced solid electrolytes with good interfacial stability toward electrodes is a highly relevant research topic for all-solid-state batteries. Here, we report PCL/SN blends integrating with PAN-skeleton as solid polymer electrolyte prepared by a facile method. This polymer electrolyte with hierarchical architectures exhibits high ionic conductivity, large electrochemical windows, high degree flexibility, good flame-retardance ability, and thermal stability (workable at 80 °C). Additionally, it demonstrates superior compatibility and electrochemical stability toward metallic Li as well as LiFePO 4 cathode. The electrolyte/electrode interfaces are very stable even subjected to 4.5 V at charging state for long time. The LiFePO 4 /Li all-solid-state cells based on this electrolyte deliver high capacity, outstanding cycling stability, and superior rate capability better than those based on liquid electrolyte. This solid polymer electrolyte is eligible for next generation high energy density all-solid-state batteries.

  17. Process performance of high-solids batch anaerobic digestion of sewage sludge.

    PubMed

    Liao, Xiaocong; Li, Huan; Cheng, Yingchao; Chen, Nan; Li, Chenchen; Yang, Yuning

    2014-01-01

    The characteristics of high-solids anaerobic digestion (AD) of sewage sludge were investigated by comparison with conventional low-solids processes. A series of batch experiments were conducted under mesophilic condition and the initial solid contents were controlled at four levels of 1.79%, 4.47%, 10.28% and 15.67%. During these experiments, biogas production, organic degradation and intermediate products were monitored. The results verified that high-solids batch AD of sewage sludge was feasible. Compared with the low-solids AD with solid contents of 1.79% or 4.47%, the high-solids processes decreased the specific biogas yield per gram of sludge volatile solids slightly, achieved the same organic degradation rate of about 40% within extended degradation time, but increased the volumetric biogas production rate and the treatment capability of digesters significantly. The blocked mass and energy transfer, the low substrate to inoculum rate and the excessive cumulative free ammonia were the main factors impacting the performance of high-solids batch AD.

  18. Synthesis of azines in solid state: reactivity of solid hydrazine with aldehydes and ketones.

    PubMed

    Lee, Byeongno; Lee, Kyu Hyung; Cho, Jaeheung; Nam, Wonwoo; Hur, Nam Hwi

    2011-12-16

    Highly conjugated azines were prepared by solid state grinding of solid hydrazine and carbonyl compounds such as aldehydes and ketones, using a mortar and a pestle. Complete conversion to the azine product is generally achieved at room temperature within 24 h, without using solvents or additives. The solid-state reactions afford azines as the sole products with greater than 97% yield, producing only water and carbon dioxide as waste.

  19. 40 CFR 256.23 - Requirements for closing or upgrading open dumps.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) SOLID WASTES GUIDELINES FOR DEVELOPMENT AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Solid... classification of existing solid waste disposal facilities according to the criteria. This classification shall... solid waste disposal facility; (2) The availability of State regulatory and enforcement powers; and (3...

  20. 40 CFR 256.23 - Requirements for closing or upgrading open dumps.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) SOLID WASTES GUIDELINES FOR DEVELOPMENT AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Solid... classification of existing solid waste disposal facilities according to the criteria. This classification shall... solid waste disposal facility; (2) The availability of State regulatory and enforcement powers; and (3...

  1. Ultraviolet 320 nm laser excitation for flow cytometry.

    PubMed

    Telford, William; Stickland, Lynn; Koschorreck, Marco

    2017-04-01

    Although multiple lasers and high-dimensional analysis capability are now standard on advanced flow cytometers, ultraviolet (UV) lasers (usually 325-365 nm) remain an uncommon excitation source for cytometry. This is primarily due to their cost, and the small number of applications that require this wavelength. The development of the Brilliant Ultraviolet (BUV fluorochromes, however, has increased the importance of this formerly niche excitation wavelength. Historically, UV excitation was usually provided by water-cooled argon- and krypton-ion lasers. Modern flow cytometers primary rely on diode pumped solid state lasers emitting at 355 nm. While useful for all UV-excited applications, DPSS UV lasers are still large by modern solid state laser standards, and remain very expensive. Smaller and cheaper near UV laser diodes (NUVLDs) emitting at 375 nm make adequate substitutes for 355 nm sources in many situations, but do not work as well with very short wavelength probes like the fluorescent calcium chelator indo-1. In this study, we evaluate a newly available UV 320 nm laser for flow cytometry. While shorter in wavelength that conventional UV lasers, 320 is close to the 325 nm helium-cadmium wavelength used in the past on early benchtop cytometers. A UV 320 nm laser was found to excite almost all Brilliant Ultraviolet dyes to nearly the same level as 355 nm sources. Both 320 nm and 355 nm sources worked equally well for Hoechst and DyeCycle Violet side population analysis of stem cells in mouse hematopoetic tissue. The shorter wavelength UV source also showed excellent excitation of indo-1, a probe that is not compatible with NUVLD 375 nm sources. In summary, a 320 nm laser module made a suitable substitute for conventional 355 nm sources. This laser technology is available in a smaller form factor than current 355 nm units, making it useful for small cytometers with space constraints. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

  2. Computational methods for reactive transport modeling: An extended law of mass-action, xLMA, method for multiphase equilibrium calculations

    NASA Astrophysics Data System (ADS)

    Leal, Allan M. M.; Kulik, Dmitrii A.; Kosakowski, Georg; Saar, Martin O.

    2016-10-01

    We present an extended law of mass-action (xLMA) method for multiphase equilibrium calculations and apply it in the context of reactive transport modeling. This extended LMA formulation differs from its conventional counterpart in that (i) it is directly derived from the Gibbs energy minimization (GEM) problem (i.e., the fundamental problem that describes the state of equilibrium of a chemical system under constant temperature and pressure); and (ii) it extends the conventional mass-action equations with Lagrange multipliers from the Gibbs energy minimization problem, which can be interpreted as stability indices of the chemical species. Accounting for these multipliers enables the method to determine all stable phases without presuming their types (e.g., aqueous, gaseous) or their presence in the equilibrium state. Therefore, the here proposed xLMA method inherits traits of Gibbs energy minimization algorithms that allow it to naturally detect the phases present in equilibrium, which can be single-component phases (e.g., pure solids or liquids) or non-ideal multi-component phases (e.g., aqueous, melts, gaseous, solid solutions, adsorption, or ion exchange). Moreover, our xLMA method requires no technique that tentatively adds or removes reactions based on phase stability indices (e.g., saturation indices for minerals), since the extended mass-action equations are valid even when their corresponding reactions involve unstable species. We successfully apply the proposed method to a reactive transport modeling problem in which we use PHREEQC and GEMS as alternative backends for the calculation of thermodynamic properties such as equilibrium constants of reactions, standard chemical potentials of species, and activity coefficients. Our tests show that our algorithm is efficient and robust for demanding applications, such as reactive transport modeling, where it converges within 1-3 iterations in most cases. The proposed xLMA method is implemented in Reaktoro, a unified open-source framework for modeling chemically reactive systems.

  3. A Novel Infrared Gas Monitor

    NASA Astrophysics Data System (ADS)

    Wang, Yingding; Zhong, Hongjie

    2000-03-01

    In the paper a novel non-dispersive infrared(IR) gas monitor is described.It is based on the principle that certain gases absorb IR radiation at specific(and often unique) wavelengths.Conventional devices typically include several primary components:a broadband source, usually an incandescent filament,a rotating chopper shutter,a narrow-band filter,a sample tube and a detector. We have developed a number of IR light emitting diodes(LED) having narrow optical bandwidths and which can be intensity modulated by electrical means,for example InAsSbP(4.2 micron)LED.The IR LED can thus replace the thermal source,narrow-band filter and chopper assembly of the conventional IR gas monitor,yielding a solid state,low- powered,compact and almost maintenance-free instrument with high sensitivity and stability and which free of the effects of mechanical vibration too. The detector used in the IR gas monitor is the solid-state detector,such as PbS,PbSe, InSb,HgCdTe,TGS,LT and PZT detector etc. The different configuration of the IR gas monitor is designed.For example,two-path version for measuring methane concentration by monitoring the 3.31 micron absorption band,it can eliminate the interference effects,such as to compensate for LED intensity changes caused by power and temperature variations,and for signal fluctuations due to changes in detector bias. we also have designed portable single-beam version without the sample tube.Its most primary advantage is very cheap(about cost USD 30 ).It measures carbon dioxide concentration by monitoring the 4.25 micron absorption band.Thought its precisions is low,it is used to control carbon dioxide concentration in the air in the green houses and plastic houses(there are about twenty millon one in the China).Because more carbon dioxide will increase the quanity of vegetable and flower production to a greatextent. It also is used in medical,sanitary and antiepidemic applications,such as hospital, store,hotel,cabin and ballroom etc. Key words:infrared gas monitor LED

  4. Strange but True: The Physics of Glass, Gels and Jellies Is All Related through Rheology

    ERIC Educational Resources Information Center

    Sarker, Dipak K.

    2017-01-01

    Rheology is an enormously far-reaching branch of physics (or physical chemistry) and has a number of different guises. Rheological descriptions define fluids, semi-solids and conventional solids, and the application of this science defines the performance and utility of materials and substances as diverse as foods (such as yogurt and marmalade),…

  5. Czochralski growth of NaNO3-LiNO3 solid solution single crystals using axial vibrational control technique

    NASA Astrophysics Data System (ADS)

    Avetissov, Igor; Sadovskiy, Andrei; Belov, Stanislav; Kong Khan, Chan; Mozhevitina, Elena; Sukhanova, Ekaterina; Zharikov, Eugeniy

    2014-09-01

    T-x diagram of LiNO3-NaNO3 quasi-binary system has been improved using an original technique based on Raman measurements of condense phase. (LiNO3)x(NaNO3)1-x solid solution single crystal has been grown at different regimes of axial vibrational control (AVC) technique. Significant difference in segregation coefficient behavior between AVC-CZ and conventional CZ grown crystals has appeared: with AVC intensity increase the segregation coefficient (SC) raises for light molecular weight elements, SC reduces for medium molecular weight elements, and SC remains practically unchangeable for heavy molecular weight elements. Effect of vibrational intensity on vibron and optical characteristics, microhardness of AVC-CZ (LiNO3)x(NaNO3)1-x solid solution single crystals has been studied. For the AVC-CZ crystals has been observed increases in microhardness as well as in optical transmission up to 10 rel% compare to conventional CZ grown crystals.

  6. Atomistic Simulation of Interfaces in Materials of Solid State Ionics

    NASA Astrophysics Data System (ADS)

    Ivanov-Schitz, A. K.; Mazo, G. N.

    2018-01-01

    The possibilities of describing correctly interfaces of different types in solids within a computer experiment using molecular statics simulation, molecular dynamics simulation, and quantum chemical calculations are discussed. Heterophase boundaries of various types, including grain boundaries and solid electrolyte‒solid electrolyte and ionic conductor‒electrode material interfaces, are considered. Specific microstructural features and mechanisms of the ion transport in real heterophase structures (cationic conductor‒metal anode and anionic conductor‒cathode) existing in solid state ionics devices (such as solid-state batteries and fuel cells) are discussed.

  7. Tunable solid state lasers for remote sensing; Proceedings of the Conference, Stanford University, CA, October 1-3, 1984

    NASA Technical Reports Server (NTRS)

    Byer, R. L. (Editor); Trebino, R. (Editor); Gustafson, E. K. (Editor)

    1985-01-01

    Papers are presented on solid-state lasers for remote sensing, diode-pumped Nd:YAG lasers, and tunable solid-state-laser systems. Topics discussed include titanium-sapphire tunable laser systems, the performance of slab geometry, and the development of slab lasers. Consideration is given to garnet host solid-state lasers, the growth of lasers and nonlinear materials, and nonlinear frequency conversion and tunable sources.

  8. Nanowire membrane-based nanothermite: towards processable and tunable interfacial diffusion for solid state reactions.

    PubMed

    Yang, Yong; Wang, Peng-peng; Zhang, Zhi-cheng; Liu, Hui-ling; Zhang, Jingchao; Zhuang, Jing; Wang, Xun

    2013-01-01

    Interfacial diffusion is of great importance in determining the performance of solid-state reactions. For nanometer sized particles, some solid-state reactions can be triggered accidently by mechanical stress owing to their large surface-to-volume ratio compared with the bulk ones. Therefore, a great challenge is the control of interfacial diffusion for solid state reactions, especially for energetic materials. Here we demonstrate, through the example of nanowire-based thermite membrane, that the thermite solid-state reaction can be easily tuned via the introduction of low-surface-energy coating layer. Moreover, this silicon-coated thermite membrane exhibit controlled wetting behavior ranging from superhydrophilic to superhydrophobic and, simultaneously, to significantly reduce the friction sensitivity of thermite membrane. This effect enables to increase interfacial resistance by increasing the amount of coating material. Indeed, our results described here make it possible to tune the solid-state reactions through the manipulation of interfacial diffusion between the reactants.

  9. Nanowire Membrane-based Nanothermite: towards Processable and Tunable Interfacial Diffusion for Solid State Reactions

    NASA Astrophysics Data System (ADS)

    Yang, Yong; Wang, Peng-Peng; Zhang, Zhi-Cheng; Liu, Hui-Ling; Zhang, Jingchao; Zhuang, Jing; Wang, Xun

    2013-04-01

    Interfacial diffusion is of great importance in determining the performance of solid-state reactions. For nanometer sized particles, some solid-state reactions can be triggered accidently by mechanical stress owing to their large surface-to-volume ratio compared with the bulk ones. Therefore, a great challenge is the control of interfacial diffusion for solid state reactions, especially for energetic materials. Here we demonstrate, through the example of nanowire-based thermite membrane, that the thermite solid-state reaction can be easily tuned via the introduction of low-surface-energy coating layer. Moreover, this silicon-coated thermite membrane exhibit controlled wetting behavior ranging from superhydrophilic to superhydrophobic and, simultaneously, to significantly reduce the friction sensitivity of thermite membrane. This effect enables to increase interfacial resistance by increasing the amount of coating material. Indeed, our results described here make it possible to tune the solid-state reactions through the manipulation of interfacial diffusion between the reactants.

  10. Bottom-up electrochemical preparation of solid-state carbon nanodots directly from nitriles/ionic liquids using carbon-free electrodes and the applications in specific ferric ion detection and cell imaging

    NASA Astrophysics Data System (ADS)

    Niu, Fushuang; Xu, Yuanhong; Liu, Mengli; Sun, Jing; Guo, Pengran; Liu, Jingquan

    2016-03-01

    Carbon nanodots (C-dots), a new type of potential alternative to conventional semiconductor quantum dots, have attracted numerous attentions in various applications including bio-chemical sensing, cell imaging, etc., due to their chemical inertness, low toxicity and flexible functionalization. Various methods including electrochemical (EC) methods have been reported for the synthesis of C-dots. However, complex procedures and/or carbon source-containing electrodes are often required. Herein, solid-state C-dots were simply prepared by bottom-up EC carbonization of nitriles (e.g. acetonitrile) in the presence of an ionic liquid [e.g. 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6)], using carbon-free electrodes. Due to the positive charges of BMIM+ on the C-dots, the final products presented in a precipitate form on the cathode, and the unreacted nitriles and BMIMPF6 can be easily removed by simple vacuum filtration. The as-prepared solid-state C-dots can be well dispersed in an aqueous medium with excellent photoluminescence properties. The average size of the C-dots was found to be 3.02 +/- 0.12 nm as evidenced by transmission electron microscopy. Other techniques such as UV-vis spectroscopy, fluorescence spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy were applied for the characterization of the C-dots and to analyze the possible generation mechanism. These C-dots have been successfully applied in efficient cell imaging and specific ferric ion detection.Carbon nanodots (C-dots), a new type of potential alternative to conventional semiconductor quantum dots, have attracted numerous attentions in various applications including bio-chemical sensing, cell imaging, etc., due to their chemical inertness, low toxicity and flexible functionalization. Various methods including electrochemical (EC) methods have been reported for the synthesis of C-dots. However, complex procedures and/or carbon source-containing electrodes are often required. Herein, solid-state C-dots were simply prepared by bottom-up EC carbonization of nitriles (e.g. acetonitrile) in the presence of an ionic liquid [e.g. 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6)], using carbon-free electrodes. Due to the positive charges of BMIM+ on the C-dots, the final products presented in a precipitate form on the cathode, and the unreacted nitriles and BMIMPF6 can be easily removed by simple vacuum filtration. The as-prepared solid-state C-dots can be well dispersed in an aqueous medium with excellent photoluminescence properties. The average size of the C-dots was found to be 3.02 +/- 0.12 nm as evidenced by transmission electron microscopy. Other techniques such as UV-vis spectroscopy, fluorescence spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy were applied for the characterization of the C-dots and to analyze the possible generation mechanism. These C-dots have been successfully applied in efficient cell imaging and specific ferric ion detection. Electronic supplementary information (ESI) available: Fig. S1. TEM image of the products generated via an electrochemical method using pure BMIMBF4 aqueous solution as the electrolyte; Fig. S2. TEM and HRTEM (inset) images of the water-dispersed solution of C-dots generated from the EC process using electrolytes with a BMIMPF6/3-methylaminopropionitrile volume ratio of 1 : 9 Fig. S3. The effect of pH on the fluorescence intensity (I) of the C-dots; experimental details for detection of Fe3+ in tap water; Fig. S4. Calibration curve for detection of Fe3+ in tap water using the standard addition method. See DOI: 10.1039/c6nr00023a

  11. 76 FR 58496 - Agency Information Collection Activities; Proposed Collection; Comment Request; State Program...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... Activities; Proposed Collection; Comment Request; State Program Adequacy Determination: Municipal Solid Waste... States. Title: State Program Adequacy Determination: Municipal Solid Waste Landfills (MSWLFs) and Non... 4004(a) and Section 1008(a)(3). Section 4005(c) of RCRA, as amended by the Hazardous Solid Waste...

  12. Development of subminiature multi-sensor hot-wire probes

    NASA Technical Reports Server (NTRS)

    Westphal, Russell V.; Ligrani, Phillip M.; Lemos, Fred R.

    1988-01-01

    Limitations on the spatial resolution of multisensor hot wire probes have precluded accurate measurements of Reynolds stresses very near solid surfaces in wind tunnels and in many practical aerodynamic flows. The fabrication, calibration and qualification testing of very small single horizontal and X-array hot-wire probes which are intended to be used near solid boundaries in turbulent flows where length scales are particularly small, is described. Details of the sensor fabrication procedure are reported, along with information needed to successfully operate the probes. As compared with conventional probes, manufacture of the subminiature probes is more complex, requiring special equipment and careful handling. The subminiature probes tested were more fragile and shorter lived than conventional probes; they obeyed the same calibration laws but with slightly larger experimental uncertainty. In spite of these disadvantages, measurements of mean statistical quantities and spectra demonstrate the ability of the subminiature sensors to provide the measurements in the near wall region of turbulent boundary layers that are more accurate than conventional sized probes.

  13. Comparative Plasma Exposure of Albendazole after Administration of Rapidly Disintegrating Tablets in Dogs

    PubMed Central

    Castro, Silvina G.; Dib, Alicia; Suarez, Gonzalo; Allemandi, Daniel; Lanusse, Carlos; Sanchez Bruni, Sergio; Palma, Santiago D.

    2013-01-01

    The main objectives of this study were (a) to evaluate the in vitro performance of the rapid disintegration tablets as a way to improve the solid dispersions and (b) to study the in vivo pharmacokinetics of the albendazole modified formulation in dogs. Rapid disintegration of tablets seems to be a key factor for efficiency of solid dispersions with regard to improvement of the albendazole bioavailability. The in vivo assays performed on dogs showed a marked increase in drug plasma exposure when albendazole was given in solid dispersions incorporated into rapid disintegration tablets compared with conventional solid dosage form. PMID:24063016

  14. [Formulation and special investigations of innovative intraoral solid dosage forms.

    PubMed

    Kristo, K; kATONA, B; Piukovics, P; Olah, I; Sipos, B; Sipos, S E; Sovany, T; Hodi, K; Ifi Regdon, G

    During our work, we summarized the types of solid dosage forms which were in the focus of attention in the last years because of their innovative pharmaceutical technology solution and simple use. The biopharmaceutics of solid dosage forms for intraoral use and the advantages of the use of these dosages forms were presented in general. However, these dosage forms cannot always be prepared with conventional pharmaceutical processes, therefore the special pharmaceutical solutions which can be applied for their preparation were presented. In addition to testing the European Pharmacopoeia dosage forms, the special tests which can be applied for the characterization of innovative solid dosage forms were highlighted.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Biogasification of community-derived biomass and solid wastes in a pilot-scale SOLCON reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Srivastava, V.J.; Biljetina, R.; Isaacson, H.R.

    1988-01-01

    The Institute of Gas Technology has developed a novel, solids- concentrating (SOLCON) bioreactor to convert a variety of individual or mixed feedstocks (biomass and wastes) to methane at higher rates and efficiencies than those obtained from conventional high-rate anaerobic digesters. The biogasification studies are being conducted in a pilot-scale experimental test unit (ETU) located in the Walt Disney World Resort Complex, Orlando, Florida. This paper describes the ETU facility, the logistics of feedstock integration, the SOLCON reactor design and operating techniques, and the results obtained during 4 years of stable, uninterrupted operation with different feedstocks. The SOLCON reactor consistently outperformedmore » the conventional stirred-tank reactor by 20% to 50%.« less

  17. Solid-State Cloud Radar System (CRS) Upgrade and Deployment

    NASA Technical Reports Server (NTRS)

    McLinden, Matt; Heymsfield, Gerald; Li, Lihua; Racette, Paul; Coon, Michael; Venkatesh, Vijay

    2015-01-01

    The recent decade has brought rapid development in solid-state power amplifier (SSPA) technology. This has enabled the use of solid-state precipitation radar in place of high-power and high-voltage systems such as those that use Klystron or Magnetron transmitters. The NASA Goddard Space Flight Center has recently completed a comprehensive redesign of the 94 gigahertz Cloud Radar System (CRS) to incorporate a solid-state transmitter. It is the first cloud radar to achieve sensitivity comparable to that of a high-voltage transmitter using solid-state. The NASA Goddard Space Flight Center's Cloud Radar System (CRS) is a 94 gigahertz Doppler radar that flies on the NASA ER-2 high-altitude aircraft. The upgraded CRS system utilizes a state-of-the-art solid-state 94 gigahertz power amplifier with a peak transmit power of 30 watts. The modernized CRS system is detailed here with data results from its deployment during the 2014 Integrated Precipitation and Hydrology Experiment (IPHEX).

  18. Use of a heated graphite scrubber as a means of reducing interferences in UV-absorbance measurements of atmospheric ozone

    NASA Astrophysics Data System (ADS)

    Turnipseed, Andrew A.; Andersen, Peter C.; Williford, Craig J.; Ennis, Christine A.; Birks, John W.

    2017-06-01

    A new solid-phase scrubber for use in conventional ozone (O3) photometers was investigated as a means of reducing interferences from other UV-absorbing species and water vapor. It was found that when heated to 100-130 °C, a tubular graphite scrubber efficiently removed up to 500 ppb ozone and ozone monitors using the heated graphite scrubber were found to be less susceptible to interferences from water vapor, mercury vapor, and aromatic volatile organic compounds (VOCs) compared to conventional metal oxide scrubbers. Ambient measurements from a graphite scrubber-equipped photometer and a co-located Federal equivalent method (FEM) ozone analyzer showed excellent agreement over 38 days of measurements and indicated no loss in the scrubber's ability to remove ozone when operated at 130 °C. The use of a heated graphite scrubber was found to reduce the interference from mercury vapor to ≤ 3 % of that obtained using a packed-bed Hopcalite scrubber. For a series of substituted aromatic compounds (ranging in volatility and absorption cross section at 253.7 nm), the graphite scrubber was observed to consistently exhibit reduced levels of interference, typically by factors of 2.5 to 20 less than with Hopcalite. Conventional solid-phase scrubbers also exhibited complex VOC adsorption and desorption characteristics that were dependent upon the relative humidity (RH), volatility of the VOC, and the available surface area of the scrubber. This complex behavior involving humidity is avoided by use of a heated graphite scrubber. These results suggest that heated graphite scrubbers could be substituted in most ozone photometers as a means of reducing interferences from other UV-absorbing species found in the atmosphere. This could be particularly important in ozone monitoring for compliance with the United States (U.S.) Clean Air Act or for use in VOC-rich environments such as in smog chambers and monitoring indoor air quality.

  19. Glass for Solid State Devices

    NASA Technical Reports Server (NTRS)

    Bailey, R. F.

    1982-01-01

    Glass film has low intrinsic compressive stress for isolating active layers of magnetic-bubble and other solid-state devices. Solid-state device structure incorporates low-stress glasses as barrier and spacer layers. Glass layers mechanically isolate substrate, conductor, and nickel/iron layers.

  20. Effects of Drying Process on an IgG1 Monoclonal Antibody Using Solid-State Hydrogen Deuterium Exchange with Mass Spectrometric Analysis (ssHDX-MS).

    PubMed

    Moussa, Ehab M; Wilson, Nathan E; Zhou, Qi Tony; Singh, Satish K; Nema, Sandeep; Topp, Elizabeth M

    2018-01-03

    Lyophilization and spray drying are widely used to manufacture solid forms of therapeutic proteins. Lyophilization is used to stabilize proteins vulnerable to degradation in solution, whereas spray drying is mainly used to prepare inhalation powders or as an alternative to freezing for storing bulk drug substance. Both processes impose stresses that may adversely affect protein structure, stability and bioactivity. Here, we compared lyophilization with and without controlled ice nucleation, and spray drying for their effects on the solid-state conformation and matrix interactions of a model IgG1 monoclonal antibody (mAb). Solid-state conformation and matrix interactions of the mAb were probed using solid-state hydrogen-deuterium exchange with mass spectrometric analysis (ssHDX-MS), and solid-state Fourier transform infrared (ssFTIR) and solid-state fluorescence spectroscopies. mAb conformation and/or matrix interactions were most perturbed in mannitol-containing samples and the distribution of states was more heterogeneous in sucrose and trehalose samples that were spray dried. The findings demonstrate the sensitivity of ssHDX-MS to changes weakly indicated by spectroscopic methods, and support the broader use of ssHDX-MS to probe formulation and process effects on proteins in solid samples.

  1. Raman spectra and anomalies of dielectric properties and thermal expansion of lead-free (1-x)Na0.5Bi0.5TiO3-xSrTiO3 (x = 0, 0.08 and 0.1) ceramics

    NASA Astrophysics Data System (ADS)

    Dutkiewicz, E. M.; Suchanicz, J.; Bovtun, V.; Konieczny, K.; Czaja, P.; Kluczewska, K.; Handke, B.; Antonova, M.; Sternberg, A.

    2016-08-01

    Thermal expansion, Raman and dielectric properties of the lead-free (1-x)Na0.5Bi0.5TiO3-xSrTiO3 (x = 0, 0.08 and 0.1) ceramic solid solutions, fabricated by the conventional solid-state reaction method, were investigated. The Sr-doping results in an increase of the dielectric permittivity, broadening of the permittivity maximum, enhancement of the relaxation near depolarization temperature, broadening of the Raman bands and shift of all anomalies toward lower temperatures. The observed effects are attributed to an increase of the degree of cationic disorder and enhancement of the relaxor-like features. Anomalies in the thermal expansion strain were observed at the temperatures corresponding to the dielectric anomalies but not related to any phase transitions. These anomalies are supposed to follow changes of the averaged unit cell volume in the temperature interval of tetragonal and rhombohedral phase coexistence.

  2. Band Gap Distortion in Semiconductors Strongly Driven by Intense Mid-Infrared Laser Fields

    NASA Astrophysics Data System (ADS)

    Kono, J.; Chin, A. H.

    2000-03-01

    Crystalline solids non-resonantly driven by intense time-periodic electric fields are predicted to exhibit unusual band-gap distortion.(e.g., Y. Yacoby, Phys. Rev. 169, 610 (1968); L.C.M. Miranda, Solid State Commun. 45, 783 (1983); J.Z. Kaminski, Acta Physica Polonica A 83, 495(1993).) Such non-perturbative effects have not been observed to date because of the unavoidable sample damage due to the very high intensity required using conventional lasers ( 1 eV photon energy). Here, we report the first clear evidence of laser-induced bandgap shrinkage in semiconductors under intense mid-infrared (MIR) laser fields. The use of long-wavelength light reduces the required intensity and prohibits strong interband absorption, thereby avoiding the damage problem. The significant sub-bandgap absorption persists only during the existence of the MIR laser pulse, indicating the virtual nature of the effect. We show that this particular example of non-perturbative behavior, known as the dynamical Franz-Keldysh effect, occurs when the effective ponderomotive potential energy is comparable to the photon energy of the applied field. This work was supported by ONR, NSF, JST and NEDO.

  3. Study of the Effect on Ionic Conductivity and Structral Morphology of the SR Doped Lanthanum Gallate Solid Electrolyte

    NASA Astrophysics Data System (ADS)

    Sood, Kapil; Singh, K.; Pandey, O. P.

    2013-07-01

    In the present study, lanthanum gallate and Sr-doped lanthanum gallate samples were prepared by conventional solid state reaction method. The phase conformation has been performed by using X-ray diffraction (XRD) study. The elemental composition has been confirmed using energy dispersive spectroscopy (EDS) analysis. Ac conductivity of the samples has been measured in the frequency range 0.1-106 Hz and from 50-800 °C. The impedance plots among real and complex impedances at particular temperature have been discussed. The behavior shows the effect of bulk and grain boundary effects of the doped sample. The impedance plots with frequency have been analyzed. The plots have been well fitted to equivalent circuit model. The conductivity shows the Arrhenius type of behavior. The activation energy has been calculated from the plots and represents that the conductivity through the material is mainly ionic. The structural morphology of the samples has been investigated using scanning electron microscope (SEM). The micrograph shows that the porosity and grain size both decreases with Sr-doping.

  4. Non-aqueous phase cold vapor generation and determination of trace cadmium by atomic fluorescence spectrometry.

    PubMed

    Lei, Zirong; Chen, Luqiong; Hu, Kan; Yang, Shengchun; Wen, Xiaodong

    2018-06-05

    Cold vapor generation (CVG) of cadmium was firstly accomplished in non-aqueous media by using solid reductant of potassium borohydride (KBH 4 ) as a derivation reagent. The mixture of surfactant Triton X-114 micelle and octanol was innovatively used as the non-aqueous media for the CVG and atomic fluorescence spectrometry (AFS) was used for the elemental determination. The analyte ions were firstly extracted into the non-aqueous media from the bulk aqueous phase of analyte/sample solution via a novelly established ultrasound-assisted rapidly synergistic cloud point extraction (UARS-CPE) process and then directly mixed with the solid redcutant KBH 4 to generate volatile elemental state cadmium in a specially designed reactor, which was then rapidly transported to a commercial atomic fluorescence spectrometer for detection. Under the optimal conditions, the limit of detection (LOD) for cadmium was 0.004 μg L -1 . Compared to conventional hydride generation (HG)-AFS, the efficiency of non-aqueous phase CVG and the analytical performance of the developed system was considerably improved. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Nanoparticles-Emerging Potential for Managing Leukemia and Lymphoma.

    PubMed

    Vinhas, Raquel; Mendes, Rita; Fernandes, Alexandra R; Baptista, Pedro V

    2017-01-01

    Nanotechnology has become a powerful approach to improve the way we diagnose and treat cancer. In particular, nanoparticles (NPs) possess unique features for enhanced sensitivity and selectivity for earlier detection of circulating cancer biomarkers. In vivo , NPs enhance the therapeutic efficacy of anticancer agents when compared with conventional chemotherapy, improving vectorization and delivery, and helping to overcome drug resistance. Nanomedicine has been mostly focused on solid cancers due to take advantage from the enhanced permeability and retention (EPR) effect experienced by tissues in the close vicinity of tumors, which enhance nanomedicine's accumulation and, consequently, improve efficacy. Nanomedicines for leukemia and lymphoma, where EPR effect is not a factor, are addressed differently from solid tumors. Nevertheless, NPs have provided innovative approaches to simple and non-invasive methodologies for diagnosis and treatment in liquid tumors. In this review, we consider the state of the art on different types of nanoconstructs for the management of liquid tumors, from preclinical studies to clinical trials. We also discuss the advantages of nanoplatforms for theranostics and the central role played by NPs in this combined strategy.

  6. Plasma-based beam combiner for very high fluence and energy

    DOE PAGES

    Kirkwood, R. K.; Turnbull, D. P.; Chapman, T.; ...

    2017-10-02

    Extreme optical fluences, much beyond the damage threshold of conventional optics, are of interest for a range of high-energy-density physics applications. Nonlinear interactions of multiple beams in plasmas have the potential to produce optics that operate at much higher intensity and fluence than is possible in solids. In inertial confinement fusion experiments indirectly driven with lasers, many beams overlap in the plasma inside a hohlraum, and cross-beam energy transfer by Brillouin scattering has been employed to redistribute energy between laser beams within the target. Here in this paper, we show that in a hot, under-dense plasma the energy of manymore » input beams can be combined into a single well-collimated beam. The emerging beam has an energy of 4 kJ (over 1 ns) that is more than triple that of any incident beam, and a fluence that is more than double. Because the optic produced is plasma, and is diffractive, it is inherently capable of generating higher fluences in a single beam than solid-state refractive or reflective optics.« less

  7. Monoclinic β-Li2TiO3 nanocrystalline particles employing novel urea assisted solid state route: Synthesis, characterization and sintering behavior

    NASA Astrophysics Data System (ADS)

    Tripathi, Biranchi M.; Mohanty, Trupti; Prakash, Deep; Tyagi, A. K.; Sinha, P. K.

    2017-07-01

    Pure phase monoclinic nano-crystalline Li2TiO3 powder was synthesized by a novel urea assisted solid state synthesis method using readily available and economical precursors. A single phase and well crystalline Li2TiO3 powder has been obtained at slightly lower temperature (600-700 °C) and shorter duration (2 h) as compared to the conventional solid state method. The proposed method has significant advantages in comparison to other viable methods mainly in terms of phase purity, powder properties and sinterability. Analysis of chemical composition using inductively coupled plasma atomic emission spectroscopy (ICP-AES) shows no loss of lithium from Li2TiO3 in the proposed method. The emergence of monoclinic Li2TiO3 phase was confirmed by X-ray diffraction (XRD) pattern of as-synthesized powder. The crystallite size of Li2TiO3 powder was calculated to be in the range of 15-80 nm, which varied as a function of urea composition and temperature. The morphology of as-prepared Li2TiO3 powders was examined by scanning electron microscope (SEM). The effect of urea composition on phase and morphology was investigated so as to delineate the role of urea. Upon sintering at < 1000 °C temperature, the Li2TiO3 powder compact attained about 98% of the theoretical density with fine grained (grain size: 2-3 μm) microstructure. It indicates excellent sinter-ability of Li2TiO3 powder synthesized by the proposed method. The fine grained structure is desirable for better tritium breeding performance of Li2TiO3. Electrochemical impedance spectroscopy at variable temperature showed good electrical properties of Li2TiO3. The proposed method is simple, anticipated to be cost effective and convenient to realise for large scale production of phase pure nanocrystalline and having significantly enhanced sinter-ability Li2TiO3 powder.

  8. Dental ablation with 1064 nm, 500 ps, Diode pumped solid state laser: A preliminary study.

    PubMed

    Sozzi, Michele; Fornaini, Carlo; Cucinotta, Annamaria; Merigo, Elisabetta; Vescovi, Paolo; Selleri, Stefano

    2013-01-01

    The Er:YAG laser in conservative dentistry is. good alternative to conventional instruments. Though several studies show the advantages of these devices, some drawbacks and unsolved problems are still present, such as the cost of the device and the large dimensions of the equipment. In the present study, the effectiveness of dental surface ablation with a picosecond infrared diode-pumped solid-state (DPSS) laser was investigated. In vitro tests on extracted human teeth were carried out, with assessment of the ablation quality in the tooth and thermal increase inside the pulp chamber. A solid-state picosecond laser was used for the experiments. The samples were exposed to laser energy at 1064 nm at a frequency of 30 kHz and a 500 ps pulse width. The target teeth were cooled during exposures. The internal temperature of the pulp chamber was monitored with. thermocouple. Optical microscope images showed effective ablation with the absence of carbonisation and micro-cracks. The cooling maintained the temperature rise in the pulp chamber below the permitted 5.5°C. The main problem with the use of lasers in dentistry when teeth are the target is the heat generated in the pulp chamber of the target teeth. With lasers operating in the femtosecond mode, a better management of the internal temperature is possible, but is offset by the high cost of such devices. With the ps domain system used in the present study together with cooling using chilled water, effective and clean ablation could be achieved with a controlled thermal effect in the pulp chamber. In this preliminary study with a picosecond domain DPSS laser using water cooling for the target, effective hard tissue ablation was achieved keeping the thermal increase in the pulp within the permitted range. The results suggest that this system could be used in clinical practice with appropriate modifications.

  9. Review of Graphene as a Solid State Diffusion Barrier.

    PubMed

    Morrow, Wayne K; Pearton, Stephen J; Ren, Fan

    2016-01-06

    Conventional thin-film diffusion barriers consist of 3D bulk films with high chemical and thermal stability. The purpose of the barrier material is to prevent intermixing or penetration from the two materials that encase it. Adhesion to both top and bottom materials is critical to the success of the barrier. Here, the effectiveness of a single atomic layer of graphene as a solid-state diffusion barrier for common metal schemes used in microelectronics is reviewed, and specific examples are discussed. Initial studies of electrical contacts to graphene show a distinct separation in behavior between metallic groups that strongly or weakly bond to it. The two basic classes of metal reactions with graphene are either physisorbed metals, which bond weakly with graphene, or chemisorbed metals, which bond strongly to graphene. For graphene diffusion barrier testing on Si substrates, an effective barrier can be achieved through the formation of a carbide layer with metals that are chemisorbed. For physisorbed metals, the barrier failure mechanism is loss of adhesion at the metal–graphene interface. A graphene layer encased between two metal layers, in certain cases, can increase the binding energy of both films with graphene, however, certain combinations of metal films are detrimental to the bonding with graphene. While the prospects for graphene's future as a solid-state diffusion barrier are positive, there are open questions, and areas for future research are discussed. A better understanding of the mechanisms which influence graphene's ability to be an effective diffusion barrier in microelectronic applications is required, and additional experiments are needed on a broader range of metals, as well as common metal stack contact structures used in microelectronic applications. The role of defects in the graphene is also a key area, since they will probably influence the barrier properties. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. 13C and 19F solid-state NMR and X-ray crystallographic study of halogen-bonded frameworks featuring nitrogen-containing heterocycles.

    PubMed

    Szell, Patrick M J; Gabriel, Shaina A; Gill, Russell D D; Wan, Shirley Y H; Gabidullin, Bulat; Bryce, David L

    2017-03-01

    Halogen bonding is a noncovalent interaction between the electrophilic region of a halogen (σ-hole) and an electron donor. We report a crystallographic and structural analysis of halogen-bonded compounds by applying a combined X-ray diffraction (XRD) and solid-state nuclear magnetic resonance (SSNMR) approach. Single-crystal XRD was first used to characterize the halogen-bonded cocrystals formed between two fluorinated halogen-bond donors (1,4-diiodotetrafluorobenzene and 1,3,5-trifluoro-2,4,6-triiodobenzene) and several nitrogen-containing heterocycles (acridine, 1,10-phenanthroline, 2,3,5,6-tetramethylpyrazine, and hexamethylenetetramine). New structures are reported for the following three cocrystals, all in the P2 1 /c space group: acridine-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C 6 F 3 I 3 ·C 13 H 9 N, 1,10-phenanthroline-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C 6 F 3 I 3 ·C 12 H 8 N 2 , and 2,3,5,6-tetramethylpyrazine-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C 6 F 3 I 3 ·C 8 H 12 N 2 . 13 C and 19 F solid-state magic-angle spinning (MAS) NMR is shown to be a convenient method to characterize the structural features of the halogen-bond donor and acceptor, with chemical shifts attributable to cocrystal formation observed in the spectra of both nuclides. Cross polarization (CP) from 19 F to 13 C results in improved spectral sensitivity in characterizing the perfluorinated halogen-bond donor when compared to conventional 1 H CP. Gauge-including projector-augmented wave density functional theory (GIPAW DFT) calculations of magnetic shielding constants, along with optimization of the XRD structures, provide a final set of structures in best agreement with the experimental 13 C and 19 F chemical shifts. Data for carbons bonded to iodine remain outliers due to well-known relativistic effects.

  11. Simulation of the infiltration process of a ceramic open-pore body with a metal alloy in semi-solid state to design the manufacturing of interpenetrating phase composites

    NASA Astrophysics Data System (ADS)

    Schomer, Laura; Liewald, Mathias; Riedmüller, Kim Rouven

    2018-05-01

    Metal-ceramic Interpenetrating Phase Composites (IPC) belong to a special subcategory of composite materials and reveal enhanced properties compared to conventional composite materials. Currently, IPC are produced by infiltration of a ceramic open-pore body with liquid metal applying high pressure and I or high temperature to avoid residual porosity. However, these IPC are not able to gain their complete potential, because of structural damages and interface reactions occurring during the manufacturing process. Compared to this, the manufacturing of IPC using the semi-solid forming technology offers great perspectives due to relative low processing temperatures and reduced mechanical pressure. In this context, this paper is focusing on numerical investigations conducted by using the FLOW-3D software for gaining a deeper understanding of the infiltration of open-pore bodies with semi-solid materials. For flow simulation analysis, a geometric model and different porous media drag models have been used. They have been adjusted and compared to get a precise description of the infiltration process. Based on these fundamental numerical investigations, this paper also shows numerical investigations that were used for basically designing a semi-solid forming tool. Thereby, the development of the flow front and the pressure during the infiltration represent the basis of the evaluation. The use of an open and closed tool cavity combined with various geometries of the upper die shows different results relating to these evaluation arguments. Furthermore, different overflows were designed and its effects on the pressure at the end of the infiltration process were investigated. Thus, this paper provides a general guideline for a tool design for manufacturing of metal-ceramic IPC using semi-solid forming.

  12. Preparation and application of unhairing enzyme using solid wastes from the leather industry-an attempt toward internalization of solid wastes within the leather industry.

    PubMed

    Ramesh, Renganath Rao; Muralidharan, Vimudha; Palanivel, Saravanan

    2018-01-01

    Usage of the animal fleshing waste as the source of carbon and nitrogen for animal skin unhairing protease (EC 3.4.21) production along with agro-industrial wastes like wheat bran has been investigated. Thermal hydrolysis of delimed fleshing waste for 3 h yielded a fleshing hydrolysate (FH) having a protein content of 20.86 mg/mL and total solids of 46,600 ppm. The FH was lyophilized and spray dried to obtain fleshing hydrolysate powder (FHP) to be used along with wheat bran and rice bran for protease production. The carbon, nitrogen, hydrogen, and sulfur contents of the FHP were found to be 40.1, 13.8, 5.4, and 0.2%. The control solid-state fermented (SSF) medium without FHP showed a maximum activity of only 550 U/g. A maximum protease activity of 956 U/g was obtained by using 6% FHP (taken based on the combined total weight of wheat bran and rice bran) after 96 h of fermentation, resulting in a 1.7-fold increase in the protease activity. The total cost of producing 1 kg of FHP and the cost of producing 1000 kU of protease using FHP along with wheat bran and rice bran were found to be USD 24.62 and USD 2.08, respectively; 25% of SSF protease along with 40% water was found to be capable of unhairing the sheepskins in 7 h eliminating the hazardous conventional lime sulfide unhairing system. Thus, the leather industry's solid waste internalized for the production of unhairing enzyme resulted in a sustainable solution for pollution problems. Graphical abstract ᅟ.

  13. 76 FR 7810 - Notice of Proposed Change to Section I of the South Dakota and North Dakota State Technical Guides

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... must be made to the NRCS State Technical Guides concerning State wetland mapping conventions. The two States are proposing to issue joint State wetland mapping conventions. The joint State wetland mapping conventions will be used as part of the technical documents to conduct wetland determinations on agriculture...

  14. Effects of ultrasonication and conventional mechanical homogenization processes on the structures and dielectric properties of BaTiO3 ceramics.

    PubMed

    Akbas, Hatice Zehra; Aydin, Zeki; Yilmaz, Onur; Turgut, Selvin

    2017-01-01

    The effects of the homogenization process on the structures and dielectric properties of pure and Nb-doped BaTiO 3 ceramics have been investigated using an ultrasonic homogenization and conventional mechanical methods. The reagents were homogenized using an ultrasonic processor with high-intensity ultrasonic waves and using a compact mixer-shaker. The components and crystal types of the powders were determined by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analyses. The complex permittivity (ε ' , ε″) and AC conductivity (σ') of the samples were analyzed in a wide frequency range of 20Hz to 2MHz at room temperature. The structures and dielectric properties of pure and Nb-doped BaTiO 3 ceramics strongly depend on the homogenization process in a solid-state reaction method. Using an ultrasonic processor with high-intensity ultrasonic waves based on acoustic cavitation phenomena can make a significant improvement in producing high-purity BaTiO 3 ceramics without carbonate impurities with a small dielectric loss. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. A Membrane-Free Ferrocene-Based High-Rate Semiliquid Battery.

    PubMed

    Ding, Yu; Zhao, Yu; Yu, Guihua

    2015-06-10

    We report here a ferrocene-based membrane-free, high-rate semiliquid battery that takes advantage of a highly soluble ferrocene/ferrocenium redox couple in nonaqueous phase. The designed battery exhibits stable capacity retention up to 94% of theoretical capacity of ferrocene (145 mAh g(-1)) at a broad current rate up to 60 C owing to rapid mass transport in a liquid phase and fast redox kinetics. The diffusion coefficient and the standard reaction constant are determined to be in the order of 10(-6) cm(2) s(-1) and 10(-1) cm s(-1), respectively, orders of magnitude greater than those in a solid-phase electrode and those in conventional redox flow batteries. Additionally, the battery demonstrates power density and energy density exceeding 1400 W L(-1) and 40 Wh L(-1), respectively, and stable cyclability with capacity retention of ∼80% for 500 cycles. Compared with state-of-the-art energy storage technologies such as Li-ion batteries or conventional redox flow batteries, the proposed liquid battery shows the potential to be an efficient energy storage system with exceptionally high power and reasonable energy density.

  16. Laser Scanning In Inspection

    NASA Astrophysics Data System (ADS)

    West, Patricia; Baker, Lionel R.

    1989-03-01

    This paper is a review of the applications of laser scanning in inspection. The reasons for the choice of a laser in flying spot scanning and the optical properties of a laser beam which are of value in a scanning instrument will be given. The many methods of scanning laser beams in both one and two dimensions will be described. The use of one dimensional laser scanners for automatic surface inspection for transmitting and reflective products will be covered in detail, with particular emphasis on light collection techniques. On-line inspection applications which will be mentioned include: photographic film web, metal strip products, paper web, glass sheet, car body paint surfaces and internal cylinder bores. Two dimensional laser scanning is employed in applications where increased resolution, increased depth of focus, and better contrast are required compared with conventional vidicon TV or solid state array cameras. Such examples as special microscope laser scanning systems and a TV compatible system for use in restricted areas of a nuclear reactor will be described. The technical and economic benefits and limitations of laser scanning video systems will be compared with conventional TV and CCD array devices.

  17. Development of a method to overcome the power threshold during supercontinuum generation based on an Yb-doped photonic crystal fiber

    NASA Astrophysics Data System (ADS)

    Baselt, Tobias; Taudt, Christopher; Nelsen, Bryan; Lasagni, Andrés Fabián; Hartmann, Peter

    2018-02-01

    Optical coherence tomography benefits from the high brightness and bandwidth, as well as the spatial coherence of supercontinuum (SC) sources. The increase of spectral power density (SPD) over conventional light sources leads to shorter measuring times and higher resolutions. For some applications, only a portion of the broad spectral range can be used. Therefore, an increase of the SPD in specific limited spectral regions would provide a clear advantage over spectral filtering. This study describes a method to increase the SPD of SC sources by amplifying the excitation wavelength inside of a nonlinear photonic crystal fiber (PCF). An ytterbium-doped PCF was manufactured by a nanopowder process and used in a fiber amplifier setup as the nonlinear fiber medium. The performance of the fiber was compared with a conventional PCF that possesses comparable parameters. Finally, the system as a whole was characterized in reference to common solid-state laser-based photonic SC light sources. An order-of-magnitude improvement of the power density was observed between the wavelengths from 1100 to 1350 nm.

  18. Advantages offered by high average power picosecond lasers

    NASA Astrophysics Data System (ADS)

    Moorhouse, C.

    2011-03-01

    As electronic devices shrink in size to reduce material costs, device size and weight, thinner material thicknesses are also utilized. Feature sizes are also decreasing, which is pushing manufacturers towards single step laser direct write process as an attractive alternative to conventional, multiple step photolithography processes by eliminating process steps and the cost of chemicals. The fragile nature of these thin materials makes them difficult to machine either mechanically or with conventional nanosecond pulsewidth, Diode Pumped Solids State (DPSS) lasers. Picosecond laser pulses can cut materials with reduced damage regions and selectively remove thin films due to the reduced thermal effects of the shorter pulsewidth. Also, the high repetition rate allows high speed processing for industrial applications. Selective removal of thin films for OLED patterning, silicon solar cells and flat panel displays is discussed, as well as laser cutting of transparent materials with low melting point such as Polyethylene Terephthalate (PET). For many of these thin film applications, where low pulse energy and high repetition rate are required, throughput can be increased by the use of a novel technique to using multiple beams from a single laser source is outlined.

  19. Mechanism for Self-Reacted Friction Stir Welding

    NASA Technical Reports Server (NTRS)

    Venable, Richard; Bucher, Joseph

    2004-01-01

    A mechanism has been designed to apply the loads (the stirring and the resection forces and torques) in self-reacted friction stir welding. This mechanism differs somewhat from mechanisms used in conventional friction stir welding, as described below. The tooling needed to apply the large reaction loads in conventional friction stir welding can be complex. Self-reacted friction stir welding has become popular in the solid-state welding community as a means of reducing the complexity of tooling and to reduce costs. The main problems inherent in self-reacted friction stir welding originate in the high stresses encountered by the pin-and-shoulder assembly that produces the weld. The design of the present mechanism solves the problems. The mechanism includes a redesigned pin-and-shoulder assembly. The welding torque is transmitted into the welding pin by a square pin that fits into a square bushing with set-screws. The opposite or back shoulder is held in place by a Woodruff key and high-strength nut on a threaded shaft. The Woodruff key reacts the torque, while the nut reacts the tensile load on the shaft.

  20. Dynamic leaching and fractionation of trace elements from environmental solids exploiting a novel circulating-flow platform.

    PubMed

    Mori, Masanobu; Nakano, Koji; Sasaki, Masaya; Shinozaki, Haruka; Suzuki, Shiho; Okawara, Chitose; Miró, Manuel; Itabashi, Hideyuki

    2016-02-01

    A dynamic flow-through microcolumn extraction system based on extractant re-circulation is herein proposed as a novel analytical approach for simplification of bioaccessibility tests of trace elements in sediments. On-line metal leaching is undertaken in the format of all injection (AI) analysis, which is a sequel of flow injection analysis, but involving extraction under steady-state conditions. The minimum circulation times and flow rates required to determine the maximum bioaccessible pools of target metals (viz., Cu, Zn, Cd, and Pb) from lake and river sediment samples were estimated using Tessier's sequential extraction scheme and an acid single extraction test. The on-line AIA method was successfully validated by mass balance studies of CRM and real sediment samples. Tessier's test in on-line AI format demonstrated to be carried out by one third of extraction time (6h against more than 17 h by the conventional method), with better analytical precision (<9.2% against >15% by the conventional method) and significant decrease in blank readouts as compared with the manual batch counterpart. Copyright © 2015 Elsevier B.V. All rights reserved.

Top