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Sample records for hydrogen bond network

  1. Energetics of Hydrogen Bond Network Rearrangements in Liquid...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Bond Network Rearrangements in Liquid Water Print The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen ...

  2. Energetics of Hydrogen Bond Network Rearrangements in Liquid Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Print Wednesday, 25 May 2005 00:00 The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen bonding (H-bonding) network structure and its associated dynamics. However, despite intense experimental and theoretical scrutiny, a complete description of this structure has been elusive. Recently, with the

  3. Energetics of Hydrogen Bond Network Rearrangements in Liquid Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Print The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen bonding (H-bonding) network structure and its associated dynamics. However, despite intense experimental and theoretical scrutiny, a complete description of this structure has been elusive. Recently, with the help of their novel liquid microjet apparatus, a University of California, Berkeley, group derived

  4. Energetics of Hydrogen Bond Network Rearrangements in Liquid Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Print The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen bonding (H-bonding) network structure and its associated dynamics. However, despite intense experimental and theoretical scrutiny, a complete description of this structure has been elusive. Recently, with the help of their novel liquid microjet apparatus, a University of California, Berkeley, group derived

  5. Energetics of Hydrogen Bond Network Rearrangements in Liquid Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Print The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen bonding (H-bonding) network structure and its associated dynamics. However, despite intense experimental and theoretical scrutiny, a complete description of this structure has been elusive. Recently, with the help of their novel liquid microjet apparatus, a University of California, Berkeley, group derived

  6. Energetics of Hydrogen Bond Network Rearrangements in Liquid Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Print The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen bonding (H-bonding) network structure and its associated dynamics. However, despite intense experimental and theoretical scrutiny, a complete description of this structure has been elusive. Recently, with the help of their novel liquid microjet apparatus, a University of California, Berkeley, group derived

  7. Energetics of Hydrogen Bond Network Rearrangements in Liquid Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Print The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen bonding (H-bonding) network structure and its associated dynamics. However, despite intense experimental and theoretical scrutiny, a complete description of this structure has been elusive. Recently, with the help of their novel liquid microjet apparatus, a University of California, Berkeley, group derived

  8. Energetics of Hydrogen Bond Network Rearrangements in Liquid Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Print The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen bonding (H-bonding) network structure and its associated dynamics. However, despite intense experimental and theoretical scrutiny, a complete description of this structure has been elusive. Recently, with the help of their novel liquid microjet apparatus, a University of California, Berkeley, group derived

  9. Energetics of Hydrogen Bond Network Rearrangements in Liquid Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energetics of Hydrogen Bond Network Rearrangements in Liquid Water Print The unique chemical and physical properties of liquid water are thought to result from the highly directional hydrogen bonding (H-bonding) network structure and its associated dynamics. However, despite intense experimental and theoretical scrutiny, a complete description of this structure has been elusive. Recently, with the help of their novel liquid microjet apparatus, a University of California, Berkeley, group derived

  10. Hydrogen-Bond Networks: Strengths of Different Types of Hydrogen Bonds and An Alternative to the Low Barrier Hydrogen-Bond Proposal

    SciTech Connect (OSTI)

    Shokri, Alireza; Wang, Yanping; O'Doherty, George A.; Wang, Xue B.; Kass, Steven R.

    2013-11-27

    We report quantifying the strengths of different types of hydrogen bonds in hydrogen bond networks (HBNs) via measurement of the adiabatic electron detachment energy of the conjugate base of a small covalent polyol model compound (i.e., (HOCH2CH2CH(OH)CH2)2CHOH) in the gas phase and the pKa of the corresponding acid in DMSO. The latter result reveals that the hydrogen bonds to the charged center and those that are one solvation shell further away (i.e., primary and secondary) provide 5.3 and 2.5 pKa units of stabilization per hydrogen bond in DMSO. Computations indicate that these energies increase to 8.4 and 3.9 pKa units in benzene and that the total stabilizations are 16 (DMSO) and 25 (benzene) pKa units. Calculations on a larger linear heptaol (i.e., (HOCH2CH2CH(OH)CH2CH(OH)CH2)2CHOH) reveal that the terminal hydroxyl groups each contribute 0.6 pKa units of stabilization in DMSO and 1.1 pKa units in benzene. All of these results taken together indicate that the presence of a charged center can provide a powerful energetic driving force for enzyme catalysis and conformational changes such as in protein folding due to multiple hydrogen bonds in a HBN.

  11. Pressure-induced localisation of the hydrogen-bond network in KOH-VI

    SciTech Connect (OSTI)

    Hermann, Andreas Nelmes, Richard J.; Loveday, John S.; Guthrie, Malcolm

    2015-12-28

    Using a combination of ab initio crystal structure prediction and neutron diffraction techniques, we have solved the full structure of KOH-VI at 7 GPa. Rather than being orthorhombic and proton-ordered as had previously be proposed, we find that this high-pressure phase of potassium hydroxide is tetragonal (space group I4/mmm) and proton disordered. It has an unusual hydrogen bond topology, where the hydroxyl groups form isolated hydrogen-bonded square planar (OH){sub 4} units. This structure is stable above 6.5 GPa and, despite being macroscopically proton-disordered, local ice rules enforce microscopic order of the hydrogen bonds. We suggest the use of this novel type of structure to study concerted proton tunneling in the solid state, while the topology of the hydrogen bond network could conceivably be exploited in data storage applications based solely on the manipulations of hydrogen bonds. The unusual localisation of the hydrogen bond network under applied pressure is found to be favored by a more compact packing of the constituents in a distorted cesium chloride structure.

  12. The hydrogen-bond network of water supports propagating optical phonon-like modes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Elton, Daniel C.; Fernández-Serra, Marivi

    2016-01-04

    The local structure of liquid water as a function of temperature is a source of intense research. This structure is intimately linked to the dynamics of water molecules, which can be measured using Raman and infrared spectroscopies. The assignment of spectral peaks depends on whether they are collective modes or single-molecule motions. Vibrational modes in liquids are usually considered to be associated to the motions of single molecules or small clusters. Using molecular dynamics simulations, here we find dispersive optical phonon-like modes in the librational and OH-stretching bands. We argue that on subpicosecond time scales these modes propagate through water’smore » hydrogen-bond network over distances of up to 2 nm. In the long wavelength limit these optical modes exhibit longitudinal–transverse splitting, indicating the presence of coherent long-range dipole–dipole interactions, as in ice. Lastly, our results indicate the dynamics of liquid water have more similarities to ice than previously thought.« less

  13. Cooperative Roles of Charge Transfer and Dispersion Terms in Hydrogen-Bonded Networks of (H2O)n, n = 6, 11, and 16

    SciTech Connect (OSTI)

    Iwata, Suehiro; Bandyopadhyay, Pradipta; Xantheas, Sotiris S.

    2013-08-01

    The perturbation expansion based on the locally-projected molecular orbital (LPMO PT) was applied to the study of the hydrogenbonded networks of water clusters with up to 16 molecules. Utilizing the local nature of the occupied and excited MOs on each monomer, the chargetransfer and dispersion terms are evaluated for every pair of molecules. The two terms are strongly correlated with each other for the hydrogen-bonded pairs. The strength of the hydrogen bonds in the clusters is further classified by the types of the hydrogen donor and acceptor water molecules. The relative energies evaluated with th LPMO PT among the isomers of (H2O)6, (H2O)11, and (H2O)16 agree very well with those obtained from CCSD(T) calculations with large basis sets. The binding energy of the LPMO PT is approximately free of the basis set superposition errors caused both by the orbital basis inconsistency and by the configuration basis inconsistency.

  14. Hydrogen Adsorption Induces Interlayer Carbon Bond Formation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Adsorption Induces Interlayer Carbon Bond Formation in Supported Few-Layer ... that only a sub-monolayer amount of hydrogen adsorption on the topmost layer results ...

  15. Probing the hydrogen-bond network of water via time-resolved soft x-ray spectroscopy

    SciTech Connect (OSTI)

    Huse, Nils; Wen, Haidan; Nordlund, Dennis; Szilagyi, Erzsi; Daranciang, Dan; Miller, Timothy A.; Nilsson, Anders; Schoenlein, Robert W.; Lindenberg, Aaron M.

    2009-04-24

    We report time-resolved studies of hydrogen bonding in liquid H2O, in response to direct excitation of the O-H stretch mode at 3 mu m, probed via soft x-ray absorption spectroscopy at the oxygen K-edge. This approach employs a newly developed nanofluidic cell for transient soft x-ray spectroscopy in liquid phase. Distinct changes in the near-edge spectral region (XANES) are observed, and are indicative of a transient temperature rise of 10K following transient laser excitation and rapid thermalization of vibrational energy. The rapid heating occurs at constant volume and the associated increase in internal pressure, estimated to be 8MPa, is manifest by distinct spectral changes that differ from those induced by temperature alone. We conclude that the near-edge spectral shape of the oxygen K-edge is a sensitive probe of internal pressure, opening new possibilities for testing the validity of water models and providing new insight into the nature of hydrogen bonding in water.

  16. Hydrogen bond dynamics in bulk alcohols

    SciTech Connect (OSTI)

    Shinokita, Keisuke; Cunha, Ana V.; Jansen, Thomas L. C.; Pshenichnikov, Maxim S.

    2015-06-07

    Hydrogen-bonded liquids play a significant role in numerous chemical and biological phenomena. In the past decade, impressive developments in multidimensional vibrational spectroscopy and combined molecular dynamicsquantum mechanical simulation have established many intriguing features of hydrogen bond dynamics in one of the fundamental solvents in nature, water. The next class of a hydrogen-bonded liquidalcoholshas attracted much less attention. This is surprising given such important differences between water and alcohols as the imbalance between the number of hydrogen bonds, each molecule can accept (two) and donate (one) and the very presence of the hydrophobic group in alcohols. Here, we use polarization-resolved pump-probe and 2D infrared spectroscopy supported by extensive theoretical modeling to investigate hydrogen bond dynamics in methanol, ethanol, and isopropanol employing the OH stretching mode as a reporter. The sub-ps dynamics in alcohols are similar to those in water as they are determined by similar librational and hydrogen-bond stretch motions. However, lower density of hydrogen bond acceptors and donors in alcohols leads to the appearance of slow diffusion-controlled hydrogen bond exchange dynamics, which are essentially absent in water. We anticipate that the findings herein would have a potential impact on fundamental chemistry and biology as many processes in nature involve the interplay of hydrophobic and hydrophilic groups.

  17. Does fluoride disrupt hydrogen bond network in cationic lipid bilayer? Time-dependent fluorescence shift of Laurdan and molecular dynamics simulations

    SciTech Connect (OSTI)

    Pokorna, Sarka; Jurkiewicz, Piotr; Hof, Martin; Vazdar, Mario; Cwiklik, Lukasz; Jungwirth, Pavel

    2014-12-14

    Time-dependent fluorescence shift (TDFS) of Laurdan embedded in phospholipid bilayers reports on hydration and mobility of the phospholipid acylgroups. Exchange of H{sub 2}O with D{sub 2}O prolongs the lifetime of lipid-water and lipid-water-lipid interactions, which is reflected in a significantly slower TDFS kinetics. Combining TDFS measurements in H{sub 2}O and D{sub 2}O hydrated bilayers with atomistic molecular dynamics (MD) simulations provides a unique tool for characterization of the hydrogen bonding at the acylgroup level of lipid bilayers. In this work, we use this approach to study the influence of fluoride anions on the properties of cationic bilayers composed of trimethylammonium-propane (DOTAP). The results obtained for DOTAP are confronted with those for neutral phosphatidylcholine (DOPC) bilayers. Both in DOTAP and DOPC H{sub 2}O/D{sub 2}O exchange prolongs hydrogen-bonding lifetime and does not disturb bilayer structure. These results are confirmed by MD simulations. TDFS experiments show, however, that for DOTAP this effect is cancelled in the presence of fluoride ions. We interpret these results as evidence that strongly hydrated fluoride is able to steal water molecules that bridge lipid carbonyls. Consequently, when attracted to DOTAP bilayer, fluoride disrupts the local hydrogen-bonding network, and the differences in TDFS kinetics between H{sub 2}O and D{sub 2}O hydrated bilayers are no longer observed. A distinct behavior of fluoride is also evidenced by MD simulations, which show different lipid-ion binding for Cl{sup −} and F{sup −}.

  18. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Surprising Path for Proton Transfer Without Hydrogen Bonds Print Hydrogen bonds are found everywhere in chemistry and biology and are critical in DNA and RNA. A hydrogen bond...

  19. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Surprising Path for Proton Transfer Without Hydrogen Bonds A Surprising Path for Proton Transfer Without Hydrogen Bonds Print Wednesday, 25 July 2012 00:00 Hydrogen bonds are...

  20. Intramolecular hydrogen bonding as a synthetic tool to induce...

    Office of Scientific and Technical Information (OSTI)

    hydrogen bonding as a synthetic tool to induce chemical selectivity in acid catalyzed porphyrin synthesis Citation Details In-Document Search Title: Intramolecular hydrogen bonding ...

  1. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Surprising Path for Proton Transfer Without Hydrogen Bonds A Surprising Path for Proton Transfer Without Hydrogen Bonds Print Wednesday, 25 July 2012 00:00 Hydrogen bonds are found everywhere in chemistry and biology and are critical in DNA and RNA. A hydrogen bond results from the attractive dipolar interaction of a chemical group containing a hydrogen atom with a group containing an electronegative atom, such as nitrogen, oxygen, or fluorine, in the same or a different molecule. Conventional

  2. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Surprising Path for Proton Transfer Without Hydrogen Bonds Print Hydrogen bonds are found everywhere in chemistry and biology and are critical in DNA and RNA. A hydrogen bond results from the attractive dipolar interaction of a chemical group containing a hydrogen atom with a group containing an electronegative atom, such as nitrogen, oxygen, or fluorine, in the same or a different molecule. Conventional wisdom has it that proton transfer from one molecule to another can only happen via

  3. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Surprising Path for Proton Transfer Without Hydrogen Bonds Print Hydrogen bonds are found everywhere in chemistry and biology and are critical in DNA and RNA. A hydrogen bond results from the attractive dipolar interaction of a chemical group containing a hydrogen atom with a group containing an electronegative atom, such as nitrogen, oxygen, or fluorine, in the same or a different molecule. Conventional wisdom has it that proton transfer from one molecule to another can only happen via

  4. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Surprising Path for Proton Transfer Without Hydrogen Bonds Print Hydrogen bonds are found everywhere in chemistry and biology and are critical in DNA and RNA. A hydrogen bond results from the attractive dipolar interaction of a chemical group containing a hydrogen atom with a group containing an electronegative atom, such as nitrogen, oxygen, or fluorine, in the same or a different molecule. Conventional wisdom has it that proton transfer from one molecule to another can only happen via

  5. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Surprising Path for Proton Transfer Without Hydrogen Bonds Print Hydrogen bonds are found everywhere in chemistry and biology and are critical in DNA and RNA. A hydrogen bond results from the attractive dipolar interaction of a chemical group containing a hydrogen atom with a group containing an electronegative atom, such as nitrogen, oxygen, or fluorine, in the same or a different molecule. Conventional wisdom has it that proton transfer from one molecule to another can only happen via

  6. Pressure-Induced Hydrogen Bond Symmetrization in Iron Oxyhydroxide...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Pressure-Induced Hydrogen Bond Symmetrization in Iron Oxyhydroxide ... Publication Date: 2014-07-21 OSTI Identifier: 1123936 Resource Type: Journal Article ...

  7. Intramolecular hydrogen bonding as a synthetic tool to induce chemical

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    selectivity in acid catalyzed porphyrin synthesis Intramolecular hydrogen bonding as a synthetic tool to induce chemical selectivity in acid catalyzed porphyrin synthesis Authors: Megiatto, J. D., Patterson, D., Sherman, B. D., Moore, T. A., Gust, D., and Moore, A. L. Title: Intramolecular hydrogen bonding as a synthetic tool to induce chemical selectivity in acid catalyzed porphyrin synthesis Source: Chemical Communications Year: 2012 Volume: 48 Pages: 4558-4560 ABSTRACT: A straightforward

  8. Northeast Hydrogen Station Network Summary

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    World leader in gases, technologies and services for Industry and Health June 10, 2016 NE Hydrogen Station Network Summary DOE AMR 2016 2 World leader in gases, technologies and services for Industry and Health East Coast Planned Fueling network- Stations 12 Stations for the North East  NYC and Long Island- (4)  Boston Area - (4)  Connecter Stations - (1) Hartford, CT & (1) Providence, RI  Northern New Jersey- (2) 6/18/2016 3 World leader in gases, technologies and services for

  9. Glassy dynamics of hydrogen-bonded heteroditopic molecules

    SciTech Connect (OSTI)

    Lou, Nan; Wang, Yangyang; Li, Haixia; Sokolov, Alexei P; Xiong, Huiming

    2012-01-01

    A self-complementary heteroditopic molecule composed of thymine and diamidopyridine end groups and a flexible aliphatic interconnecting chain has been synthesized. The glassy dynamics of this hydrogen-bonded supramolecule have been investigated by using dielectric and rheological measurements, in combination with infra-red spectroscopy and solid-state 13C NMR experiments. Decoupling of main dielectric relaxation from viscosity has been found in the vicinity of the glass transition and the temperature dependence of viscosity appears to be stronger than that of dielectric relaxation. The unusual dynamic decoupling phenomenon is ascribed to the chemical/dynamic heterogeneity and formation of hydrogen bonds in the supramolecules.

  10. Hydrogen Adsorption Induces Interlayer Carbon Bond Formation in Supported

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Few-Layer Graphene | Stanford Synchrotron Radiation Lightsource Hydrogen Adsorption Induces Interlayer Carbon Bond Formation in Supported Few-Layer Graphene Friday, February 28, 2014 Among the allotropes of carbon, diamond has some of the most remarkable physical properties of any material in terms of hardness, stiffness, thermal conductivity, transparency and chemical inertness1. Graphite, which is the most thermodynamically stable form of carbon at room temperature and at ambient

  11. Hydrogen Bonding Under High-Pressure (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Conference: Hydrogen Bonding Under High-Pressure Citation Details In-Document Search ... Subject: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY Word Cloud More Like ...

  12. Panel 2, Hydrogen Delivery in the Natural Gas Pipeline Network

    Broader source: Energy.gov (indexed) [DOE]

    the Natural Gas Pipeline Network DOE'S HYDROGEN ENERGY STORAGE FOR GRID AND ... >Unanswered Questions >CEC's Mobile Hydrogen Station 3 3 Company Overview ESTABLISHED ...

  13. Blending Hydrogen into Natural Gas Pipeline Networks: A Review...

    Broader source: Energy.gov (indexed) [DOE]

    This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and natural gas mixture to defray the cost of building ...

  14. Structural Aspects of Hydrogen Bonding with Nitrate and Sulfate: Design Criteria for Polyalcohol Hosts

    SciTech Connect (OSTI)

    Hay, Benjamin P.; Dixon, David A.; Lumetta, Gregg J.; Vargas, Rubicelia; Garza, Jorge

    2004-01-01

    Organic hosts for oxyanion complexation can be constructed by combining two or more hydrogen bonding sites. The deliberate design of architectures for such hosts requires knowledge of the optimal geometry for the hydrogen bonds formed between the host and the guest. Important structural parameters include the O--H distance, the O--H-D angle, the X-O--H angle, and the X-O--H-D dihedral angle (H-D=hydrogen bond donor, X=any atom). This information can be obtained through the analysis of hydrogen bonding observed in crystal structures and electronic structure calculations on simple gas-phase complexes. In this chapter, we present an analysis of hydrogen bonding structural parameters for alcohol hydrogen donors and the oxygen atom acceptors in nitrate and sulfate.

  15. California Hydrogen Highway Network October 3, 2007

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrogen Highway Network April 3, 2008 California Air Resources Board California Blueprint Plan * Phased approach to infrastructure implementation * Environmental goals * Shared risk CaH2Net Background * Governor's Executive Order, S-7-04 formed the CaH2Net in April 2004 * A Blueprint Plan, May 2005 * Legislative Authority - SB76, $6.5 Million, stations, vehicles, support - Budget Act 2006, $6.5 Million, ZBuses, stations - Budget Act 2007, $6 Million, stations, support The State's Contribution *

  16. Ultrafast conversions between hydrogen bonded structures in liquid water observed by femtosecond x-ray spectroscopy

    SciTech Connect (OSTI)

    Wen, Haidan; Huse, Nils; Schoenlein, Robert W.; Lindenberg, Aaron M.

    2010-05-01

    We present the first femtosecond soft x-ray spectroscopy in liquids, enabling the observation of changes in hydrogen bond structures in water via core-hole excitation. The oxygen K-edge of vibrationally excited water is probed with femtosecond soft x-ray pulses, exploiting the relation between different water structures and distinct x-ray spectral features. After excitation of the intramolecular OH stretching vibration, characteristic x-ray absorption changes monitor the conversion of strongly hydrogen-bonded water structures to more disordered structures with weaker hydrogen-bonding described by a single subpicosecond time constant. The latter describes the thermalization time of vibrational excitations and defines the characteristic maximum rate with which nonequilibrium populations of more strongly hydrogen-bonded water structures convert to less-bonded ones. On short time scales, the relaxation of vibrational excitations leads to a transient high-pressure state and a transient absorption spectrum different from that of statically heated water.

  17. Hydrogen-bond Specific Materials Modification in Group IV Semiconductors

    SciTech Connect (OSTI)

    Tolk, Norman H.; Feldman, L. C.; Luepke, G.

    2015-09-14

    Executive summary Semiconductor dielectric crystals consist of two fundamental components: lattice atoms and electrons. The former component provides a crystalline structure that can be disrupted by various defects or the presence of an interface, or by transient oscillations known as phonons. The latter component produces an energetic structure that is responsible for the optical and electronic properties of the material, and can be perturbed by lattice defects or by photo-excitation. Over the period of this project, August 15, 1999 to March 31, 2015, a persistent theme has been the elucidation of the fundamental role of defects arising from the presence of radiation damage, impurities (in particular, hydrogen), localized strain or some combination of all three. As our research effort developed and evolved, we have experienced a few title changes, which reflected this evolution. Throughout the project, ultrafast lasers usually in a pump-probe configuration provided the ideal means to perturb and study semiconductor crystals by both forms of excitation, vibrational (phonon) and electronic (photon). Moreover, we have found in the course of this research that there are many interesting and relevant scientific questions that may be explored when phonon and photon excitations are controlled separately. Our early goals were to explore the dynamics of bond-selective vibrational excitation of hydrogen from point defects and impurities in crystalline and amorphous solids, initiating an investigation into the behavior of hydrogen isotopes utilizing a variety of ultrafast characterization techniques, principally transient bleaching spectroscopy to experimentally obtain vibrational lifetimes. The initiative could be divided into three related areas: (a) investigation of the change in electronic structure of solids due to the presence of hydrogen defect centers, (b) dynamical studies of hydrogen in materials and (c) characterization and stability of metastable hydrogen

  18. Pressure-induced magnetic crossover driven by hydrogen bonding in CuF2(H2O)2(3-chloropyridine)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    O'Neal, Kenneth R.; Brinzari, Tatiana V.; Wright, Joshua B.; Ma, Chunli; Giri, Santanab; Schlueter, John A.; Wang, Qian; Jena, Puru; Liu, Zhenxian; Musfeldt, Janice L.

    2014-08-13

    Here, hydrogen bonding plays a foundational role in the life, earth, and chemical sciences, with its richness and strength depending on the situation. In molecular materials, these interactions determine assembly mechanisms, control superconductivity, and even permit magnetic exchange. In spite of its long-standing importance, exquisite control of hydrogen bonding in molecule-based magnets has only been realized in limited form and remains as one of the major challenges. Here, we report the discovery that pressure can tune the dimensionality of hydrogen bonding networks in CuF2(H2O)2(3-chloropyridine) to induce magnetic switching. Specifically, we reveal how the development of exchange pathways under compression combinedmore » with an enhanced ab-plane hydrogen bonding network yields a three dimensional superexchange web between copper centers that triggers a reversible magnetic crossover. Similar pressure- and strain-driven crossover mechanisms involving coordinated motion of hydrogen bond networks may play out in other quantum magnets.« less

  19. Sulfate Recognition by Persistent Crystalline Capsules with Rigidified Hydrogen Bonding Cavities

    SciTech Connect (OSTI)

    Custelcean, Radu; Remy, Priscilla; Jiang, Deen; Bonnesen, Peter V; Moyer, Bruce A

    2008-01-01

    electivity is a fundamental property of pervasive importance in chemistry and biology as reflected in phenomena as diverse as membrane transport, catalysis, sensing, adsorption, complexation, and crystallization. Although the key principles of complementarity and preorganization governing the binding interactions underlying such phenomena were delineated long ago, truly profound selectivity has proven elusive by design in part because synthetic molecular architectures are neither maximally complementary for binding target species nor sufficiently rigid. Even if a host molecule possesses a high degree of complementarity for a guest species, it all too often can distort its structure or even rearrange its conformation altogether to accommodate competing guests. One approach taken by researchers to overcome this challenge has been to devise extremely rigid molecules that bind species within complementary cavities. Although examples have been reported to demonstrate the principle, such cases are not generally of practical utility, because of inefficient synthesis and often poor kinetics. Alternatively, flexible building blocks can be employed, but then the challenge becomes one of locking them in place. Taking a cue from natural binding agents that derive their rigidity from a network of molecular interactions, especially hydrogen bonding, we present herein an example of a crystalline, self-assembled capsule that binds sulfate by a highly complementary array of rigidified hydrogen bonds (H-bonds). Although covalent or self-assembled capsules have been previously employed as anion hosts, they typically lack the strict combination of complementarity and rigidity required for high selectivity. Furthermore, the available structural data for these systems is either restricted to a limited number of anions of similar size and shape, or varies significantly from one anion to another, which hampers the rationalization of the observed selectivity. We have been employing

  20. Hydrogen-bond acidic functionalized carbon nanotubes (CNTs) with covalently-bound hexafluoroisopropanol groups

    SciTech Connect (OSTI)

    Fifield, Leonard S.; Grate, Jay W.

    2010-06-01

    Fluorinated hydrogen-bond acidic groups are directly attached to the backbone of single walled carbon nanotubes (SWCNTs) without the introduction of intermediate electron donating surface groups. Hexafluoroalcohol functional groups are exceptionally strong hydrogen bond acids, and are added to the nanotube surface using the aryl diazonium approach to create hydrogen-bond acidic carbon nanotube (CNT) surfaces. These groups can promote strong hydrogen-bonding interactions with matrix materials in composites or with molecular species to be concentrated and sensed. In the latter case, this newly developed material is expected to find useful application in chemical sensors and in CNT-based preconcentrator devices for the detection of pesticides, chemical warfare agents and explosives.

  1. Short strong hydrogen bonds in proteins: a case study of rhamnogalacturonan acetylesterase

    SciTech Connect (OSTI)

    Langkilde, Annette; Kristensen, Søren M.; Lo Leggio, Leila; Mølgaard, Anne; Jensen, Jan H.; Houk, Andrew R.; Navarro Poulsen, Jens-Christian; Kauppinen, Sakari; Larsen, Sine

    2008-08-01

    The short hydrogen bonds in rhamnogalacturonan acetylesterase have been investigated by structure determination of an active-site mutant, {sup 1}H NMR spectra and computational methods. Comparisons are made to database statistics. A very short carboxylic acid carboxylate hydrogen bond, buried in the protein, could explain the low-field (18 p.p.m.) {sup 1}H NMR signal. An extremely low-field signal (at approximately 18 p.p.m.) in the {sup 1}H NMR spectrum of rhamnogalacturonan acetylesterase (RGAE) shows the presence of a short strong hydrogen bond in the structure. This signal was also present in the mutant RGAE D192N, in which Asp192, which is part of the catalytic triad, has been replaced with Asn. A careful analysis of wild-type RGAE and RGAE D192N was conducted with the purpose of identifying possible candidates for the short hydrogen bond with the 18 p.p.m. deshielded proton. Theoretical calculations of chemical shift values were used in the interpretation of the experimental {sup 1}H NMR spectra. The crystal structure of RGAE D192N was determined to 1.33 Å resolution and refined to an R value of 11.6% for all data. The structure is virtually identical to the high-resolution (1.12 Å) structure of the wild-type enzyme except for the interactions involving the mutation and a disordered loop. Searches of the Cambridge Structural Database were conducted to obtain information on the donor–acceptor distances of different types of hydrogen bonds. The short hydrogen-bond interactions found in RGAE have equivalents in small-molecule structures. An examination of the short hydrogen bonds in RGAE, the calculated pK{sub a} values and solvent-accessibilities identified a buried carboxylic acid carboxylate hydrogen bond between Asp75 and Asp87 as the likely origin of the 18 p.p.m. signal. Similar hydrogen-bond interactions between two Asp or Glu carboxy groups were found in 16% of a homology-reduced set of high-quality structures extracted from the PDB. The shortest

  2. California Hydrogen Highway Network October 3, 2007 | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrogen Highway Network October 3, 2007 California Hydrogen Highway Network October 3, 2007 Presented at Refueling Infrastructure for Alternative Fuel Vehicles: Lessons Learned for Hydrogen Conference, April 2-3, 2008, Sacramento, California bevan_carb_h2hwynet.pdf (451.31 KB) More Documents & Publications California Regulations on Renewble Hydrogen and Low Carbon Technologies Panel Session III: Innovation and Coordination Asia/ITS

  3. Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds Print Wednesday, 28 June 2006 00:00 Two of the major challenges for humanity in the next 20 years are the shrinking availability of fossil fuels and the global warming and potential climate changes that result from their ever-increasing use. One possible solution to these problems is to use an energy carrier such as hydrogen, and ways to produce and store

  4. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    9.0.2. To examine how the molecules were bonded, the team first created a gaseous molecular beam of methylated uracil monomers and dimers, then ionized them with vacuum...

  5. Determination of Hydrogen Bond Structure in Water versus Aprotic Environments To Test the Relationship Between Length and Stability

    SciTech Connect (OSTI)

    Sigala, Paul A.; Ruben, Eliza A.; Liu, Corey W.; Piccoli, Paula M. B.; Hohenstein, Edward G.; Martinez, Todd J.; Schultz, Arthur J.; Herschiag, Daniel

    2015-05-06

    Hydrogen bonds profoundly influence the architecture and activity of biological macromolecules. Deep appreciation of hydrogen bond contributions to biomolecular function thus requires a detailed understanding of hydrogen bond structure and energetics and the relationship between these properties. Hydrogen bond formation energies (Delta G(f)) are enormously more favorable in aprotic solvents than in water, and two classes of contributing factors have been proposed to explain this energetic difference, focusing respectively on the isolated and hydrogen-bonded species: (I) water stabilizes the dissociated donor and acceptor groups much better than aprotic solvents, thereby reducing the driving force for hydrogen bond formation; and (II) water lengthens hydrogen bonds compared to aprotic environments, thereby decreasing the potential energy within the hydrogen bond. Each model has been proposed to provide a dominant contribution to Delta G(f), but incisive tests that distinguish the importance of these contributions are lacking. Here we directly test the structural basis of model II. Neutron crystallography, NMR spectroscopy, and quantum mechanical calculations demonstrate that O-H center dot center dot center dot O hydrogen bonds in crystals, chloroform, acetone, and water have nearly identical lengths and very similar potential energy surfaces despite Delta G(f) differences >8 kcal/mol across these solvents. These results rule out a substantial contribution from solvent-dependent differences in hydrogen bond structure and potential energy after association (model II) and thus support the conclusion that differences in hydrogen bond Delta G(f) are predominantly determined by solvent interactions with the dissociated groups (model I). These findings advance our understanding of universal hydrogen-bonding interactions and have important implications for biology and engineering.

  6. Californias Hydrogen Fueling Network Status and Challenges

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    CALIFORNIA'S HYDROGEN FUELING NETWORK STATUS AND CHALLENGES June 10, 2016 For questions or comments, contact: Andrew Martinez (916) 322-8449 andrew.martinez@arb.ca.gov CURRENT NETWORK STATUS California's Hydrogen Network 50 Funded and Planned by 2017 23 Open and Fueling Vehicles Today 24! Campbell Current Development Status *Includes Fountain Valley as Open- Non-Retail, which is not expected to continue beyond 2016 18! FCEV Deployment June 2016 AB 8 Report Coming Soon! ? ? ? 2016 HyStEP Update *

  7. Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds Print Two of the major challenges for humanity in the next 20 years are the shrinking availability of fossil fuels and the global warming and potential climate changes that result from their ever-increasing use. One possible solution to these problems is to use an energy carrier such as hydrogen, and ways to produce and store hydrogen in electric power plants and vehicles is a major research focus for materials scientists and

  8. Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds Print Two of the major challenges for humanity in the next 20 years are the shrinking availability of fossil fuels and the global warming and potential climate changes that result from their ever-increasing use. One possible solution to these problems is to use an energy carrier such as hydrogen, and ways to produce and store hydrogen in electric power plants and vehicles is a major research focus for materials scientists and

  9. Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds Print Two of the major challenges for humanity in the next 20 years are the shrinking availability of fossil fuels and the global warming and potential climate changes that result from their ever-increasing use. One possible solution to these problems is to use an energy carrier such as hydrogen, and ways to produce and store hydrogen in electric power plants and vehicles is a major research focus for materials scientists and

  10. Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds Print Two of the major challenges for humanity in the next 20 years are the shrinking availability of fossil fuels and the global warming and potential climate changes that result from their ever-increasing use. One possible solution to these problems is to use an energy carrier such as hydrogen, and ways to produce and store hydrogen in electric power plants and vehicles is a major research focus for materials scientists and

  11. Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds Print Two of the major challenges for humanity in the next 20 years are the shrinking availability of fossil fuels and the global warming and potential climate changes that result from their ever-increasing use. One possible solution to these problems is to use an energy carrier such as hydrogen, and ways to produce and store hydrogen in electric power plants and vehicles is a major research focus for materials scientists and

  12. Recognizing molecular patterns by machine learning: An agnostic structural definition of the hydrogen bond

    SciTech Connect (OSTI)

    Gasparotto, Piero; Ceriotti, Michele

    2014-11-07

    The concept of chemical bonding can ultimately be seen as a rationalization of the recurring structural patterns observed in molecules and solids. Chemical intuition is nothing but the ability to recognize and predict such patterns, and how they transform into one another. Here, we discuss how to use a computer to identify atomic patterns automatically, so as to provide an algorithmic definition of a bond based solely on structural information. We concentrate in particular on hydrogen bonding – a central concept to our understanding of the physical chemistry of water, biological systems, and many technologically important materials. Since the hydrogen bond is a somewhat fuzzy entity that covers a broad range of energies and distances, many different criteria have been proposed and used over the years, based either on sophisticate electronic structure calculations followed by an energy decomposition analysis, or on somewhat arbitrary choices of a range of structural parameters that is deemed to correspond to a hydrogen-bonded configuration. We introduce here a definition that is univocal, unbiased, and adaptive, based on our machine-learning analysis of an atomistic simulation. The strategy we propose could be easily adapted to similar scenarios, where one has to recognize or classify structural patterns in a material or chemical compound.

  13. Chemical bonding in hydrogen and lithium under pressure

    SciTech Connect (OSTI)

    Naumov, Ivan I.; Hemley, Russell J.; Hoffmann, Roald; Ashcroft, N. W.

    2015-08-14

    Though hydrogen and lithium have been assigned a common column of the periodic table, their crystalline states under common conditions are drastically different: the former at temperatures where it is crystalline is a molecular insulator, whereas the latter is a metal that takes on simple structures. On compression, however, the two come to share some structural and other similarities associated with the insulator-to-metal and metal-to-insulator transitions, respectively. To gain a deeper understanding of differences and parallels in the behaviors of compressed hydrogen and lithium, we performed an ab initio comparative study of these systems in selected identical structures. Both elements undergo a continuous pressure-induced s-p electronic transition, though this is at a much earlier stage of development for H. The valence charge density accumulates in interstitial regions in Li but not in H in structures examined over the same range of compression. Moreover, the valence charge density distributions or electron localization functions for the same arrangement of atoms mirror each other as one proceeds from one element to the other. Application of the virial theorem shows that the kinetic and potential energies jump across the first-order phase transitions in H and Li are opposite in sign because of non-local effects in the Li pseudopotential. Finally, the common tendency of compressed H and Li to adopt three-fold coordinated structures as found is explained by the fact that such structures are capable of yielding a profound pseudogap in the electronic densities of states at the Fermi level, thereby reducing the kinetic energy. These results have implications for the phase diagrams of these elements and also for the search for new structures with novel properties.

  14. Anion Binding in Metal-Organic Frameworks Functionalized with Urea Hydrogen-Bonding Groups

    SciTech Connect (OSTI)

    Custelcean, Radu; Moyer, Bruce A; Bryantsev, Vyacheslav S.; Hay, Benjamin P.

    2006-01-01

    A series of metal-organic frameworks (MOFs) functionalized with urea hydrogen-bonding groups has been synthesized and structurally analyzed by single-crystal X-ray diffraction to evaluate the efficacy of anion coordination by urea within the structural constraints of the MOFs. We found that urea-based functionalities may be used for anion binding within metal-organic frameworks when the tendency for urea{hor_ellipsis}urea self-association is decreased by strengthening the intramolecular CH{hor_ellipsis}O hydrogen bonding of N-phenyl substituents to the carbonyl oxygen atom. Theoretical calculations indicate that N,N'-bis(m-pyridyl)urea (BPU) and N,N'-bis(m-cyanophenyl)urea (BCPU) should have enhanced hydrogen-bonding donor abilities toward anions and decreased tendencies to self-associate into hydrogen-bonded tapes compared to other disubstituted ureas. Accordingly, BPU and BCPU were incorporated in MOFs as linkers through coordination of various Zn, Cu, and Ag transition metal salts, including Zn(ClO{sub 4}){sub 2}, ZnSO{sub 4}, Cu(NO{sub 3}){sub 2}, Cu(CF{sub 3}SO{sub 3}){sub 2}, AgNO{sub 3}, and AgSO{sub 3}CH{sub 3}. Structural analysis by single-crystal X-ray diffraction showed that these linkers are versatile anion binders, capable of chelate hydrogen bonding to all of the oxoanions explored. Anion coordination by the urea functionalities was found to successfully compete with urea self-association in all cases except for that of charge-diffuse perchlorate.

  15. Hydrogen-bond driven loop-closure kinetics in unfolded polypeptide chains

    SciTech Connect (OSTI)

    Daidone, Isabella [University of Heidelberg; Neuweiler, H [University of Heidelberg; Doose, S [University of Heidelberg; Sauer, M [University of Heidelberg; Smith, Jeremy C [ORNL

    2010-12-01

    Characterization of the length dependence of end-to-end loop-closure kinetics in unfolded polypeptide chains provides an understanding of early steps in protein folding. Here, loop-closure in poly-glycine-serine peptides is investigated by combining single-molecule fluorescence spectroscopy with molecular dynamics simulation. For chains containing more than 10 peptide bonds loop-closing rate constants on the 20-100 nanosecond time range exhibit a power-law length dependence. However, this scaling breaks down for shorter peptides, which exhibit slower kinetics arising from a perturbation induced by the dye reporter system used in the experimental setup. The loop-closure kinetics in the longer peptides is found to be determined by the formation of intra-peptide hydrogen bonds and transient beta-sheet structure, that accelerate the search for contacts among residues distant in sequence relative to the case of a polypeptide chain in which hydrogen bonds cannot form. Hydrogen-bond-driven polypeptide-chain collapse in unfolded peptides under physiological conditions found here is not only consistent with hierarchical models of protein folding, that highlights the importance of secondary structure formation early in the folding process, but is also shown to speed up the search for productive folding events.

  16. Enhancement in Organic Photovoltaic Efficiency through the Synergistic Interplay of Molecular Donor Hydrogen Bonding and -Stacking

    SciTech Connect (OSTI)

    Shewmon, Nathan; Watkins, Davita; Galindo, Johan; Zerdan, Raghida; Chen, Jihua; Keum, Jong Kahk; Roitberg, Adrian; Xue, Jiangeng; Castellano, Ronald

    2015-07-20

    For organic photovoltaic (OPV) cells based on the bulk heterojunction (BHJ) structure, it remains challenging to rationally control the degree of phase separation and percolation within blends of donors and acceptors to secure optimal charge separation and transport. Reported is a bottom-up, supramolecular approach to BHJ OPVs wherein tailored hydrogen bonding (H-bonding) interactions between π-conjugated electron donor molecules encourage formation of vertically aligned donor π-stacks while simultaneously suppressing lateral aggregation; the programmed arrangement facilitates fine mixing with fullerene acceptors and efficient charge transport. The approach is illustrated using conventional linear or branched quaterthiophene donor chromophores outfitted with terminal functional groups that are either capable or incapable of self-complementary H-bonding. When applied to OPVs, the H-bond capable donors yield a twofold enhancement in power conversion efficiency relative to the comparator systems, with a maximum external quantum efficiency of 64%. H-bond promoted assembly results in redshifted absorption (in neat films and donor:C 60 blends) and enhanced charge collection efficiency despite disparate donor chromophore structure. Both features positively impact photocurrent and fill factor in OPV devices. Film structural characterization by atomic force microscopy, transmission electron microscopy, and grazing incidence wide angle X-ray scattering reveals a synergistic interplay of lateral H-bonding interactions and vertical π-stacking for directing the favorable morphology of the BHJ.

  17. Enhancement in Organic Photovoltaic Efficiency through the Synergistic Interplay of Molecular Donor Hydrogen Bonding and -Stacking

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shewmon, Nathan; Watkins, Davita; Galindo, Johan; Zerdan, Raghida; Chen, Jihua; Keum, Jong Kahk; Roitberg, Adrian; Xue, Jiangeng; Castellano, Ronald

    2015-07-20

    For organic photovoltaic (OPV) cells based on the bulk heterojunction (BHJ) structure, it remains challenging to rationally control the degree of phase separation and percolation within blends of donors and acceptors to secure optimal charge separation and transport. Reported is a bottom-up, supramolecular approach to BHJ OPVs wherein tailored hydrogen bonding (H-bonding) interactions between π-conjugated electron donor molecules encourage formation of vertically aligned donor π-stacks while simultaneously suppressing lateral aggregation; the programmed arrangement facilitates fine mixing with fullerene acceptors and efficient charge transport. The approach is illustrated using conventional linear or branched quaterthiophene donor chromophores outfitted with terminal functional groupsmore » that are either capable or incapable of self-complementary H-bonding. When applied to OPVs, the H-bond capable donors yield a twofold enhancement in power conversion efficiency relative to the comparator systems, with a maximum external quantum efficiency of 64%. H-bond promoted assembly results in redshifted absorption (in neat films and donor:C 60 blends) and enhanced charge collection efficiency despite disparate donor chromophore structure. Both features positively impact photocurrent and fill factor in OPV devices. Film structural characterization by atomic force microscopy, transmission electron microscopy, and grazing incidence wide angle X-ray scattering reveals a synergistic interplay of lateral H-bonding interactions and vertical π-stacking for directing the favorable morphology of the BHJ.« less

  18. Panel 2, Hydrogen Delivery in the Natural Gas Pipeline Network

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in the Natural Gas Pipeline Network DOE'S HYDROGEN ENERGY STORAGE FOR GRID AND TRANSPORTATION SERVICES WORKSHOP Sacramento, CA May 14, 2014 Brian Weeks Gas Technology Institute 2 2 Topics for Today >GTI Introduction >Natural Gas Infrastructure is Undergoing Changes >Questions that have been addressed >Two Scenarios >Unanswered Questions >CEC's Mobile Hydrogen Station 3 3 Company Overview ESTABLISHED 1941 > Independent, not-for-profit company established by natural gas

  19. Anion Coordination in Metal-Organic Frameworks Functionalized with Urea Hydrogen-Bonding Groups

    SciTech Connect (OSTI)

    Custelcean, Radu; Moyer, Bruce A.; Bryantsev, Vyacheslav; Hay, Benjamin P.

    2005-12-15

    A series of metal-organic frameworks (MOFs) functionalized with urea hydrogen-bonding groups have been designed, synthesized, and structurally analyzed by single crystal X-ray diffraction to evaluate the efficacy of anion binding within the structural constraints of the MOFs. We found that urea-based functionalities may be used for anion binding within metal-organic frameworks when the tendency for urea???urea self-association is decreased by strengthening the intramolelcular CH???O hydrogen bonding of N-phenyl substituents to the carbonyl oxygen atom. Theoretical calculations indicate that N,N?-bis(m-pyridyl)urea (BPU) and N,N?-bis(m-cyanophenyl)urea (BCPU) should have enhanced hydrogen-bonding donor abilities toward anions and decreased tendencies to self-associate into hydrogen-bonded chains compared to other disubstituted ureas. Accordingly, BPU and BCPU were incorporated in MOFs as linkers through coordination of various Zn, Cu, and Ag transition metal salts, including Zn(ClO4)2, ZnSO4, Cu(NO3)2, Cu(CF3SO3)2, AgNO3 and AgSO3CH3. Structural analysis by single-crystal X-ray diffraction showed that these linkers are versatile anion binders, capable of chelate hydrogen bonding to all of the oxoanions explored. Anion binding by the urea functionalities was found to successfully compete with urea self-association in all cases except for that of charge-diffuse perchlorate. This research was sponsored by the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences of the U.S. Department of Energy, under contract number DE-AC05-00OR22725 with Oak Ridge National Laboratory (managed by UT-Battelle, LLC), and performed at Oak Ridge National laboratory and Pacific Northwest National Laboratory (managed by Battelle for the U.S. Department of Energy under contract DE-AC05-76RL01830). This research was performed in part using the Molecular Science Computing Facility (MSCF) in the William R. Wiley Environmental Molecular Sciences laboratory

  20. A coordinatively saturated sulfate encapsulated in a metal-organic framework functionalized with urea hydrogen-bonding groups

    SciTech Connect (OSTI)

    Custelcean, Radu; Moyer, Bruce A.; Hay, Benjamin P.

    2005-10-14

    A functional coordination polymer decorated with urea hydrogen-bonding donor groups has been designed for optional binding of sulfate; self-assembly of a tripodal tri-urea linker with Ag2SO4 resulted in the formation of a 1D metal-organic framework that encapsulated SO42- anions via twelve complementary hydrogen bonds, which represents the highest coordination number observed for sulfate in a natural or synthetic host.

  1. A coordinatively saturated sulfate encapsulated in a metal-organic framework functionalized with urea hydrogen-bonding groups

    SciTech Connect (OSTI)

    Custelcean, Radu; Moyer, Bruce A; Hay, Benjamin

    2005-01-01

    A functional coordination polymer decorated with urea hydrogen-bonding donor groups has been designed for optimal binding of sulfate; self-assembly of a tripodal tris-urea linker with Ag2SO4 resulted in the formation of a 1D metal - organic framework that encapsulates SO42- anions via twelve complementary hydrogen bonds, which represents the highest coordination number observed for sulfate in a natural or synthetic host.

  2. Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key Issues

    Fuel Cell Technologies Publication and Product Library (EERE)

    This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and natural gas mixture to defray the cost of building dedicated hydrogen pipeline

  3. Blending Hydrogen into Natural Gas Pipeline Networks. A Review of Key Issues

    SciTech Connect (OSTI)

    Melaina, M. W.; Antonia, O.; Penev, M.

    2013-03-01

    This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and natural gas mixture to defray the cost of building dedicated hydrogen pipelines. Blending hydrogen into the existing natural gas pipeline network has also been proposed as a means of increasing the output of renewable energy systems such as large wind farms.

  4. Observation of Fractional Stokes-Einstein Behavior in the Simplest Hydrogen-bonded Liquid

    SciTech Connect (OSTI)

    Herwig, Kenneth W; Molaison, Jamie J; Fernandez-Alonso, F.; Bermejo, F. J.; Turner, John F. C.; McLain, Sylvia E.

    2007-01-01

    Quasielastic neutron scattering has been used to investigate the single-particle dynamics of hydrogen fluoride across its entire liquid range at ambient pressure. For T > 230 K, translational diffusion obeys the celebrated Stokes-Einstein relation, in agreement with nuclear magnetic resonance studies. At lower temperatures, we find significant deviations from the above behavior in the form of a power law with exponent xi = -0.71+/-0.05. More striking than the above is a complete breakdown of the Debye-Stokes-Einstein relation for rotational diffusion. Our findings provide the first experimental verification of fractional Stokes-Einstein behavior in a hydrogen-bonded liquid, in agreement with recent computer simulations.

  5. Transition pathways in a many-body system: Application to hydrogen-bond breaking in water

    SciTech Connect (OSTI)

    Csajka, F.S.; Chandler, D.

    1998-07-01

    We apply a stochastic method introduced by Dellago {ital et al.} [J. Chem. Phys. {bold 108}, 1964 (1998)] to sample transition paths in high-dimensional systems. The method connects two endpoint regions (for example a reactant and a product region) by a set of space-time paths. This approach is an importance sampling for rare events that does not require prior knowledge of the location of dynamical bottlenecks. Transition paths are generated with a weight corresponding to a chain of Metropolis Monte Carlo steps. We derive Monte Carlo algorithms and apply the technique to the dynamics of hydrogen-bond breaking in liquid water. We obtain averages in a transition path ensemble for the structure and energy along the trajectory. While characterized by a rate constant, hydrogen-bond breaking in water occurs frequently enough to be studied by standard methods. The process therefore provides a useful test of path sampling methods. The comparison between path sampling and standard Monte Carlo demonstrate the feasibility of transition path sampling for a many-body system with a rough potential energy surface. {copyright} {ital 1998 American Institute of Physics.}

  6. Probing surface hydrogen bonding and dynamics by natural abundance, multidimensional, 17O DNP-NMR spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Perras, Frederic A.; Chaudhary, Umesh; Slowing, Igor I.; Pruski, Marek

    2016-05-06

    Dynamic nuclear polarization (DNP)-enhanced solid-state nuclear magnetic resonance (SSNMR) spectroscopy is increasingly being used as a tool for the atomic-level characterization of surface sites. DNP surface-enhanced SSNMR spectroscopy of materials has, however, been limited to studying relatively receptive nuclei, and the particularly rare 17O nuclide, which is of great interest for materials science, has not been utilized. We demonstrate that advanced 17O SSNMR experiments can be performed on surface species at natural isotopic abundance using DNP. We use 17O DNP surface-enhanced 2D SSNMR to measure 17O{1H} HETCOR spectra as well as dipolar oscillations on a series of thermally treatedmore » mesoporous silica nanoparticle samples having different pore diameters. These experiments allow for a nonintrusive and unambiguous characterization of hydrogen bonding and dynamics at the surface of the material; no other single experiment can give such details about the interactions at the surface. Lastly, our data show that, upon drying, strongly hydrogen-bonded surface silanols, whose motions are greatly restricted by the interaction when compared to lone silanols, are selectively dehydroxylated.« less

  7. The role of hydrogen bonds in protein folding and protein association

    SciTech Connect (OSTI)

    Ben-Naim, A. (National Inst. of Health, Bethesda, MD (USA))

    1991-02-07

    The contribution of a pair of functional groups that can form either intermolecular or intramolecular hydrogen bonds to the total standard free energy of the process of protein folding or protein association is examined. It is found that this contribution can be quite large, either positive or negative, depending on the particular process and on the solvent density. This is in contrast to the common belief that the hydrogen-bond energies tend to be compensated in these processes. For the binding process, in which the two functional groups are completely removed from the aqueous environment, the contribution of such a pair of functional groups to {Delta}G can be as high as +6.4 kcal/mol. This is the main reason why hydrophobic rather than hydrophilic surfaces tend to attach to each other. In contrast, when the two functional groups are only partially removed from the aqueous environment, as in the case of the formation of {alpha}-helix, their contribution to {Delta}G can be negative and of the order of about 1 kcal/mol.

  8. Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Issues | Department of Energy Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key Issues Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key Issues The United States has 11 distinct natural gas pipeline corridors: five originate in the Southwest, four deliver natural gas from Canada, and two extend from the Rocky Mountain region. This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and

  9. UC Davis Models: Geospatial Station Network Design Tool and Hydrogen Infrastructure Rollout Economic Analysis Model

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    UC Davis Models Geospatial Station Network Design Tool & Hydrogen Infrastructure Rollout Economic Analysis Model (University of California-Davis) Objectives Analyze regional strategies for early rollout of hydrogen infrastructure in support of fuel cell vehicle commercialization. Estimate how many hydrogen fueling stations would be needed and how much it will cost to develop cost competitive hydrogen supply. Compare the cost of hydrogen from different types and sizes of hydrogen stations

  10. Selectivity Principles in Anion Separation by Crystallization of Hydrogen-Bonding Capsules

    SciTech Connect (OSTI)

    Custelcean, Radu; Bock, Aurelien; Moyer, Bruce A

    2010-01-01

    The fundamental factors controlling anion selectivity in the crystallization of hydrogen-bonding capsules [Mg(H2O)6][X L2] (X = SO42-, 1a; SeO42-, 1b; SO32-, 1c; CO32-, 1d; L = tris[2-(3-pyridylurea)ethyl]-amine) from water have been investigated by solution and solid-state thermodynamic measurements, anion competition experiments, and X-ray structural analysis. The crystal structures of 1a-d are isomorphous, thereby simplifying the interpretation of the observed selectivities based on differences in anion coordination geometries. The solubilities of 1a-d in water follow the order: 1a < 1b < 1c < 1d, which is consistent with the selectivity for the tetrahedral sulfate and selenate anions observed in competitive crystallization experiments. Crystallization of the capsules is highly exothermic, with the most favorable {Delta}H{sub cryst}{sup o} of -99.1 and -108.5 kJ/mol corresponding to SO42- and SeO42-, respectively, in agreement with the X-ray structural data showing shape complementarity between these tetrahedral anions and the urea-lined cavities of the capsules. Sulfite, on the other hand, has a significantly less negative {Delta}H{sub cryst}{sup o} of -64.6 kJ/mol, which may be attributed to its poor fit inside the capsules, involving repulsive interactions. The more favorable entropy of crystallization for this anion, however, partly offsets the enthalpic disadvantage, resulting in a solubility product very similar to that of the selenate complex. Because of their very similar shape and size, SO42- and SeO42- have a propensity to form solid solutions, which limits the selectivity between these two anions in competitive crystallizations. In the end, a comprehensive picture of contributing factors to anion selectivity in crystalline hydrogen-bonding capsules emerges.

  11. On the competition between hydrogen abstraction versus C-O bond fission in initiating dimethyl ether combustion

    SciTech Connect (OSTI)

    Francisco, J.

    1999-07-01

    There has been a growing interest in the potential use of dimethyl ether (DME) as a diesel fuel in compression ignition engines. There are two initiation steps involved in the combustion of DME, one involving C-O bond fission and the other involving hydrogen abstraction by molecular oxygen. The kinetics and thermodynamics of C-O bond fission were explored computationally in a previous paper. The present paper addresses the competing process--hydrogen abstraction by molecular oxygen. Ab initio molecular orbital calculations are used to study the structures and energetics of the reactants, products, and the transition state for the CH{sub 3}OCH{sub 3} + O{sub 2} reaction. The calculations predict a barrier for hydrogen abstraction from CH{sub 3}OCH{sub 3} by O{sub 2} of 47.4 kcal/mol. This is lower than the barrier height for C-O bond fission previously calculated to be 81.1 kcal/mol. The results support values used in current models for the combustion of DME. Moreover, an examination of rates for C-O bond fission versus hydrogen abstraction by O{sub 2} suggests that the bimolecular process is the dominant pathway.

  12. Communication: Towards the binding energy and vibrational red shift of the simplest organic hydrogen bond: Harmonic constraints for methanol dimer

    SciTech Connect (OSTI)

    Heger, Matthias; Suhm, Martin A.; Mata, Ricardo A.

    2014-09-14

    The discrepancy between experimental and harmonically predicted shifts of the OH stretching fundamental of methanol upon hydrogen bonding to a second methanol unit is too large to be blamed mostly on diagonal and off-diagonal anharmonicity corrections. It is shown that a decisive contribution comes from post-MP2 electron correlation effects, which appear not to be captured by any of the popular density functionals. We also identify that the major deficiency is in the description of the donor OH bond. Together with estimates for the electronic and harmonically zero-point corrected dimer binding energies, this work provides essential constraints for a quantitative description of this simple hydrogen bond. The spectroscopic dissociation energy is predicted to be larger than 18 kJ/mol and the harmonic OH-stretching fundamental shifts by about ?121 cm{sup ?1} upon dimerization, somewhat more than in the anharmonic experiment (?111 cm{sup ?1})

  13. Structural Criteria for the Rational Design of Selective Ligands: Convergent Hydrogen Bonding Sites for the Nitrate Anion

    SciTech Connect (OSTI)

    Hay, Benjamin P.; Gutowski, Maciej S.; Dixon, David A.; Garza , Jorge; Vargas, Rubicelia; Moyer, Bruce A.

    2004-06-30

    Molecular hosts for anion complexation are often constructed by combining two or more hydrogen bonding functional groups, DH. The deliberate design of complementary host architectures requires knowledge of the optimal geometry for the hydrogen bonds formed between the host and the guest. Herein, we present a detailed study of the structural aspects of hydrogen bonding interactions with the NO3 anion. A large number of crystal structures are analyzed to determine the number of hydrogen bond contacts per anion and to further characterize the structural aspects of these interactions. Electronic structure calculations are used to determine stable geometries and interaction energies for NO3 complexes with several simple molecules possessing DH groups, including water, methanol, N-methylformamide, and methane. Theoretical results are reported at several levels of density functional theory, including BP86/DN**, B3LYP/TZVP, and B3LYP/TZVP+, and at MP2/aug-cc-pVDZ. In addition, MP2 binding energies for these complexes were obtained at the complete basis set limit by extrapolating from single point energies obtained with larger correlation-consistent basis sets. The results establish that NO3 has an intrinsic hydrogen bonding topography in which there are six optimal sites for proton location. The structural features observed in crystal structures and in the optimized geometries of complexes are explained by a preference to locate the DH protons in these positions. For the strongest hydrogen bonding interactions, the NOH angle is bent at an angle of 115 10, and the hydrogen atom lies in the NO3 plane giving ONOH dihedral angles of 0 and 180. In addition, the D-H vector points towards the oxygen atom, giving DHO angles that are near linear, 170 10. Due to steric hindrance, simple alcohol OH and amide NH donors form 3:1 complexes with NO3, with HO distances of 1.85 0.5 . Thus, the optimal cavity radius for a tridentate host, defined as the

  14. Proton transfer through hydrogen bonds in two-dimensional water layers: A theoretical study based on ab initio and quantum-classical simulations

    SciTech Connect (OSTI)

    Bankura, Arindam; Chandra, Amalendu

    2015-01-28

    The dynamics of proton transfer (PT) through hydrogen bonds in a two-dimensional water layer confined between two graphene sheets at room temperature are investigated through ab initio and quantum-classical simulations. The excess proton is found to be mostly solvated as an Eigen cation where the hydronium ion donates three hydrogen bonds to the neighboring water molecules. In the solvation shell of the hydronium ion, the three coordinated water molecules with two donor hydrogen bonds are found to be properly presolvated to accept a proton. Although no hydrogen bond needs to be broken for transfer of a proton to such presolvated water molecules from the hydronium ion, the PT rate is still found to be not as fast as it is for one-dimensional chains. Here, the PT is slowed down as the probability of finding a water with two donor hydrogen bonds in the solvation shell of the hydronium ion is found to be only 25%-30%. The hydroxide ion is found to be solvated mainly as a complex anion where it accepts four H-bonds through its oxygen atom and the hydrogen atom of the hydroxide ion remains free all the time. Here, the presolvation of the hydroxide ion to accept a proton requires that one of its hydrogen bonds is broken and the proton comes from a neighboring water molecule with two acceptor and one donor hydrogen bonds. The coordination number reduction by breaking of a hydrogen bond is a slow process, and also the population of water molecules with two acceptor and one donor hydrogen bonds is only 20%-25% of the total number of water molecules. All these factors together tend to slow down the hydroxide ion migration rate in two-dimensional water layers compared to that in three-dimensional bulk water.

  15. Effects of ion energy on the crystal size and hydrogen bonding in plasma-deposited nanocrystalline silicon thin films

    SciTech Connect (OSTI)

    Lebib, S.; Roca i Cabarrocas, P.

    2005-05-15

    We present a detailed study of the effects of the substrate temperature, radio-frequency (rf) power, and total pressure on the crystal size and hydrogen bonding in nanocrystalline silicon thin films codeposited on the grounded and rf electrodes of an asymmetric radio frequency glow discharge reactor. Raman spectroscopy, x-ray diffraction, and spectroscopic ellipsometry measurements show that by varying the deposition parameters we can obtain crystal sizes in the range of 3-10 nm and crystalline fractions in the range of 20% up to 97%. The obtaining of small crystallite sizes (4-5 nm) in films submitted to high-energy (100-300 eV) ion bombardment is highlighted by infrared-absorption and hydrogen evolution measurements, which display characteristic features of hydrogen bonded at the surface of the crystallites. Therefore, hydrogen bonding is a unique way to demonstrate the presence of small crystallites in films at the transition between amorphous and nanocrystalline, films which look amorphous when characterized by standard techniques such as Raman spectroscopy and x-ray diffraction.

  16. Hydrogen-bonding interactions and protic equilibria in room-temperature ionic liquids containing crown ethers.

    SciTech Connect (OSTI)

    Marin, T.; Shkrob, I.; Dietz, M.

    2011-04-14

    Nuclear magnetic resonance (NMR) spectroscopy has been used to study hydrogen-bonding interactions between water, associated and dissociated acids (i.e., nitric and methanesulfonic acids), and the constituent ions of several water-immiscible room-temperature ionic liquids (ILs). In chloroform solutions also containing a crown ether (CE), water molecules strongly associate with the IL ions, and there is rapid proton exchange between these bound water molecules and hydronium associated with the CE. In neat ILs, the acids form clusters differing in their degree of association and ionization, and their interactions with the CEs are weak. The CE can either promote proton exchange between different clusters in IL solution when their association is weak or inhibit such exchange when the association is strong. Even strongly hydrophobic ILs are shown to readily extract nitric acid from aqueous solution, typically via the formation of a 1:1:1 {l_brace}H{sub 3}O{sup +} {center_dot} CE{r_brace}NO{sub 3}{sup -} complex. In contrast, the extraction of methanesulfonic acid is less extensive and proceeds mainly by IL cation-hydronium ion exchange. The relationship of these protic equilibria to the practical application of hydrophobic ILs (e.g., in spent nuclear fuel reprocessing) is discussed.

  17. Nickel superoxide dismutase: structural and functional roles of His1 and its H-bonding network

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Maroney, Michael J.; Cabelli, Diane E.; Ryan, Kelly C.; Guce, Abigail I.; Johnson, Olivia E.; Brunold, Thomas C.; Garman, Scott C.

    2015-01-21

    Crystal structures of nickel-dependent superoxide dismutases (NiSODs) reveal the presence of a H-bonding network formed between the NH group of the apical imidazole ligand from His1 and the Glu17 carboxylate from a neighboring subunit in the hexameric enzyme. This interaction is supported by another intrasubunit H-bond between Glu17 and Arg47. In this study, four mutant NiSOD proteins were produced to experimentally evaluate the roles of this H-bonding network and compare the results with prior predictions from density functional theory calculations. The X-ray crystal structure of H1A-NiSOD, which lacks the apical ligand entirely, reveals that in the absence of the Glu17-His1more » H-bond, the active site is disordered. Characterization of this variant using X-ray absorption spectroscopy (XAS) shows that Ni(II) is bound in the expected N₂S₂ planar coordination site. Despite these structural perturbations, the H1A-NiSOD variant retains 4% of wild-type (WT) NiSOD activity. Three other mutations were designed to preserve the apical imidazole ligand but perturb the H-bonding network: R47A-NiSOD, which lacks the intramolecular H-bonding interaction; E17R/R47A-NiSOD, which retains the intramolecular H-bond but lacks the intermolecular Glu17-His1 H-bond; and E17A/R47ANiSOD, which lacks both H-bonding interactions. These variants were characterized by a combination of techniques, including XAS to probe the nickel site structure, kinetic studies employing pulse-radiolytic production of superoxide, and electron paramagnetic resonance to assess the Ni redox activity. The results indicate that in addition to the roles in redox tuning suggested on the basis of previous computational studies, the Glu17-His1 H-bond plays an important structural role in the proper folding of the “Ni-hook” motif that is a critical feature of the active site.« less

  18. Nickel superoxide dismutase: structural and functional roles of His1 and its H-bonding network

    SciTech Connect (OSTI)

    Maroney, Michael J.; Cabelli, Diane E.; Ryan, Kelly C.; Guce, Abigail I.; Johnson, Olivia E.; Brunold, Thomas C.; Garman, Scott C.

    2015-01-21

    Crystal structures of nickel-dependent superoxide dismutases (NiSODs) reveal the presence of a H-bonding network formed between the NH group of the apical imidazole ligand from His1 and the Glu17 carboxylate from a neighboring subunit in the hexameric enzyme. This interaction is supported by another intrasubunit H-bond between Glu17 and Arg47. In this study, four mutant NiSOD proteins were produced to experimentally evaluate the roles of this H-bonding network and compare the results with prior predictions from density functional theory calculations. The X-ray crystal structure of H1A-NiSOD, which lacks the apical ligand entirely, reveals that in the absence of the Glu17-His1 H-bond, the active site is disordered. Characterization of this variant using X-ray absorption spectroscopy (XAS) shows that Ni(II) is bound in the expected N?S? planar coordination site. Despite these structural perturbations, the H1A-NiSOD variant retains 4% of wild-type (WT) NiSOD activity. Three other mutations were designed to preserve the apical imidazole ligand but perturb the H-bonding network: R47A-NiSOD, which lacks the intramolecular H-bonding interaction; E17R/R47A-NiSOD, which retains the intramolecular H-bond but lacks the intermolecular Glu17-His1 H-bond; and E17A/R47ANiSOD, which lacks both H-bonding interactions. These variants were characterized by a combination of techniques, including XAS to probe the nickel site structure, kinetic studies employing pulse-radiolytic production of superoxide, and electron paramagnetic resonance to assess the Ni redox activity. The results indicate that in addition to the roles in redox tuning suggested on the basis of previous computational studies, the Glu17-His1 H-bond plays an important structural role in the proper folding of the Ni-hook motif that is a critical feature of the active site.

  19. Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key Issues

    SciTech Connect (OSTI)

    Melaina, M. W.; Antonia, O.; Penev, M.

    2013-03-01

    The United States has 11 distinct natural gas pipeline corridors: five originate in the Southwest, four deliver natural gas from Canada, and two extend from the Rocky Mountain region. This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and natural gas mixture to defray the cost of building dedicated hydrogen pipelines.

  20. The effect of large amplitude motions on the transition frequency redshift in hydrogen bonded complexes: A physical picture

    SciTech Connect (OSTI)

    Mackeprang, Kasper; Kjaergaard, Henrik G.; Salmi, Teemu; Hnninen, Vesa; Halonen, Lauri

    2014-05-14

    We describe the vibrational transitions of the donor unit in water dimer with an approach that is based on a three-dimensional local mode model. We perform a perturbative treatment of the intermolecular vibrational modes to improve the transition wavenumber of the hydrogen bonded OH-stretching transition. The model accurately predicts the transition wavenumbers of the vibrations in water dimer compared to experimental values and provides a physical picture that explains the redshift of the hydrogen bonded OH-oscillator. We find that it is unnecessary to include all six intermolecular modes in the vibrational model and that their effect can, to a good approximation, be computed using a potential energy surface calculated at a lower level electronic structure method than that used for the unperturbed model.

  1. A conformationally persistent pseudo-bicyclic guanidinium for anion coordination as stabilized by dual intramolecular hydrogen bonds

    SciTech Connect (OSTI)

    Seipp, Charles A.; Williams, Neil J.; Bryantsev, Vyacheslav S.; Custelcean, Radu; Moyer, Bruce A.

    2015-11-30

    In this paper, the first example of a pseudo-bicyclic guanidinium ligand is reported. When bound to an anion, the N,N'-bis(2-pyridyl)guanidinium cation persistently adopts the planar α,α conformation featuring intramolecular N···H–N–H···N hydrogen bonds in the solid state, which facilitates crystallization of sulphate from aqueous mixtures of anions.

  2. Hydrogen adsorption and desorption with 3D silicon nanotube-network and film-network structures: Monte Carlo simulations

    SciTech Connect (OSTI)

    Li, Ming; Kang, Zhan; Huang, Xiaobo

    2015-08-28

    Hydrogen is clean, sustainable, and renewable, thus is viewed as promising energy carrier. However, its industrial utilization is greatly hampered by the lack of effective hydrogen storage and release method. Carbon nanotubes (CNTs) were viewed as one of the potential hydrogen containers, but it has been proved that pure CNTs cannot attain the desired target capacity of hydrogen storage. In this paper, we present a numerical study on the material-driven and structure-driven hydrogen adsorption of 3D silicon networks and propose a deformation-driven hydrogen desorption approach based on molecular simulations. Two types of 3D nanostructures, silicon nanotube-network (Si-NN) and silicon film-network (Si-FN), are first investigated in terms of hydrogen adsorption and desorption capacity with grand canonical Monte Carlo simulations. It is revealed that the hydrogen storage capacity is determined by the lithium doping ratio and geometrical parameters, and the maximum hydrogen uptake can be achieved by a 3D nanostructure with optimal configuration and doping ratio obtained through design optimization technique. For hydrogen desorption, a mechanical-deformation-driven-hydrogen-release approach is proposed. Compared with temperature/pressure change-induced hydrogen desorption method, the proposed approach is so effective that nearly complete hydrogen desorption can be achieved by Si-FN nanostructures under sufficient compression but without structural failure observed. The approach is also reversible since the mechanical deformation in Si-FN nanostructures can be elastically recovered, which suggests a good reusability. This study may shed light on the mechanism of hydrogen adsorption and desorption and thus provide useful guidance toward engineering design of microstructural hydrogen (or other gas) adsorption materials.

  3. Hydrogen bonds, interfacial stiffness moduli, and the interlaminar shear strength of carbon fiber-epoxy matrix composites

    SciTech Connect (OSTI)

    Cantrell, John H.

    2015-03-15

    The chemical treatment of carbon fibers used in carbon fiber-epoxy matrix composites greatly affects the fraction of hydrogen bonds (H-bonds) formed at the fiber-matrix interface. The H-bonds are major contributors to the fiber-matrix interfacial shear strength and play a direct role in the interlaminar shear strength (ILSS) of the composite. The H-bond contributions τ to the ILSS and magnitudes K{sub N} of the fiber-matrix interfacial stiffness moduli of seven carbon fiber-epoxy matrix composites, subjected to different fiber surface treatments, are calculated from the Morse potential for the interactions of hydroxyl and carboxyl acid groups formed on the carbon fiber surfaces with epoxy receptors. The τ calculations range from 7.7 MPa to 18.4 MPa in magnitude, depending on fiber treatment. The K{sub N} calculations fall in the range (2.01 – 4.67) ×10{sup 17} N m{sup −3}. The average ratio K{sub N}/|τ| is calculated to be (2.59 ± 0.043) × 10{sup 10} m{sup −1} for the seven composites, suggesting a nearly linear connection between ILSS and H-bonding at the fiber-matrix interfaces. The linear connection indicates that τ may be assessable nondestructively from measurements of K{sub N} via a technique such as angle beam ultrasonic spectroscopy.

  4. Co-localised Raman and force spectroscopy reveal the roles of hydrogen bonds and π-π interactions in defining the mechanical properties of diphenylalanine nano- and micro-tubes

    SciTech Connect (OSTI)

    Sinjab, Faris; Bondakov, Georgi; Notingher, Ioan

    2014-06-23

    An integrated atomic force and polarized Raman microscope were used to measure the elastic properties of individual diphenylalanine (FF) nano- and micro-tubes and to obtain quantitative information regarding the inter-molecular interactions that define their mechanical properties. For individual tubes, co-localised force spectroscopy and Raman spectroscopy measurements allowed the calculation of the Young's and shear moduli (25 ± 5 GPa and 0.28 ± 0.05 GPa, respectively) and the contribution of hydrogen bonding network to the Young's modulus (∼17.6 GPa). The π-π interactions between the phenyl rings, dominated by T-type arrangements, were estimated based on previously published X-ray data to only 0.20 GPa. These results provide experimental evidence obtained from individual FF tubes that the network of H-bonds dominates the elastic properties of the FF tubes.

  5. Synthesis and structure of a 2D → 3D framework with coexistence of hydrogen bonds and polythreading character

    SciTech Connect (OSTI)

    Zhang, Ming-Dao Zhuang, Qi-Fan; Xu, Jing; Cao, Hui

    2015-12-15

    The title complex, ([Co(BPPA)(5-OH-bdc)] · (H{sub 2}O)){sub n} was prepared under hydrothermal conditions based on two ligands, namely, bis(4-(pyridin-4-yl)phenyl)amine (BPPA) and 5-hydroxyisophthalic acid (5-OH-H{sub 2}bdc). 5-OH-bdc{sup 2–} anions coordinated to Co atoms to give layers in crystal. BPPA ligands coordinate to Co atoms and thread into the adjacent layers. There are hydrogen bonds between adjacent layers, giving rise to a 2D → 3D framework.

  6. Bioinspired Molecular Co-Catalysts Bonded to a Silicon Photocathode for Solar Hydrogen Evolution

    SciTech Connect (OSTI)

    Hou, Yidong

    2011-11-08

    The production of fuels from sunlight represents one of the main challenges in the development of a sustainable energy system. Hydrogen is the simplest fuel to produce and although platinum and other noble metals are efficient catalysts for photoelectrochemical hydrogen evolution earth-abundant alternatives are needed for large-scale use. We show that bioinspired molecular clusters based on molybdenum and sulphur evolve hydrogen at rates comparable to that of platinum. The incomplete cubane-like clusters (Mo{sub 3}S{sub 4}) efficiently catalyse the evolution of hydrogen when coupled to a p-type Si semiconductor that harvests red photons in the solar spectrum. The current densities at the reversible potential match the requirement of a photoelectrochemical hydrogen production system with a solar-to-hydrogen efficiency in excess of 10% (ref. 16). The experimental observations are supported by density functional theory calculations of the Mo{sub 3}S{sub 4} clusters adsorbed on the hydrogen-terminated Si(100) surface, providing insights into the nature of the active site.

  7. Observation of slow dangling-bond relaxation in [ital p]-type hydrogenated amorphous silicon

    SciTech Connect (OSTI)

    Carlen, M.W.; Xu, Y.; Crandall, R.S. )

    1995-01-15

    Using junction-capacitance methods, we study the thermal charge emission of holes trapped in the dangling-bond defect [ital D] of [ital p]-type [ital a]-Si:H. Over a significant temperature range, we find a linear temperature-independent relation between emission time and the residence time of the hole on the [ital D] defect. We attribute this characteristic to a structural-relaxation process that is slow in disordered materials.

  8. Networks of ultrasmall Pd/Cr bilayer nanowires as high performance hydrogen sensors.

    SciTech Connect (OSTI)

    Zeng, X.-Q.; Wang, Y.-L.; Deng, H.; Latimer, M. L.; Xiao, Z.-L.; Pearson, J.; Xu, T.; Wang, H.-H.; Welp, U.; Crabtree, G. W.; Kwok, W.-K.

    2011-01-01

    The newly developed hydrogen sensor, based on a network of ultrasmall pure palladium nanowires sputter-deposited on a filtration membrane, takes advantage of single palladium nanowires' characteristics of high speed and sensitivity while eliminating their nanofabrication obstacles. However, this new type of sensor, like the single palladium nanowires, cannot distinguish hydrogen concentrations above 3%, thus limiting the potential applications of the sensor. This study reports hydrogen sensors based on a network of ultrasmall Cr-buffered Pd (Pd/Cr) nanowires on a filtration membrane. These sensors not only are able to outperform their pure Pd counterparts in speed and durability but also allow hydrogen detection at concentrations up to 100%. The new networks consist of a thin layer of palladium deposited on top of a Cr adhesion layer 1-3 nm thick. Although the Cr layer is insensitive to hydrogen, it enables the formation of a network of continuous Pd/Cr nanowires with thicknesses of the Pd layer as thin as 2 nm. The improved performance of the Pd/Cr sensors can be attributed to the increased surface area to volume ratio and to the confinement-induced suppression of the phase transition from Pd/H solid solution ({alpha}-phase) to Pd hydride ({beta}-phase).

  9. Hydrogen responses of ultrathin Pd films and nanowire networks with a Ti buffer layer.

    SciTech Connect (OSTI)

    Zeng, X. Q.; Wang, Y. L.; Xiao, Z. L.; Latimer, M. L.; Xu, T.; Kwok, W. K.

    2012-01-01

    We report on hydrogen responses of ultrathin films and nanowire networks of palladium on titanium buffered silicon substrates and filtration membranes, respectively. We found that in both systems signatures such as retarding responses and saturation of the resistance changes at high hydrogen concentrations associated with the transition from Pd/H solid solution to Pd hydride diminish with decreasing the thickness of the palladium layer from 7 to 2 nm. Our results not only reveal a new way to suppress the phase transition in Pd/H system but also provide an alternative approach to achieve fast and sensitive hydrogen sensors with a wide concentration detection range.

  10. Hydrogen gas sensing with networks of ultra-small palladium nanowires formed on filtration membranes.

    SciTech Connect (OSTI)

    Zeng, X. Q.; Latimer, M. L.; Xiao, Z. L.; Panuganti, S.; Welp, U.; Kwok, W. K.; Xu, T.

    2010-11-29

    Hydrogen sensors based on single Pd nanowires show promising results in speed, sensitivity, and ultralow power consumption. The utilization of single Pd nanowires, however, face challenges in nanofabrication, manipulation, and achieving ultrasmall transverse dimensions. We report on hydrogen sensors that take advantage of single palladium nanowires in high speed and sensitivity and that can be fabricated conveniently. The sensors are based on networks of ultrasmall (<10 nm) palladium nanowires deposited onto commercially available filtration membranes. We investigated the sensitivities and response times of these sensors as a function of the thickness of the nanowires and also compared them with a continuous reference film. The superior performance of the ultrasmall Pd nanowire network based sensors demonstrates the novelty of our fabrication approach, which can be directly applied to palladium alloy and other hydrogen sensing materials.

  11. Production of Hydrogen by Electrocatalysis: Making the H-H Bond by Combining Protons and Hydrides

    SciTech Connect (OSTI)

    Bullock, R. Morris; Appel, Aaron M.; Helm, Monte L.

    2014-03-25

    Generation of hydrogen by reduction of two protons by two electrons can be catalysed by molecular electrocatalysts. Determination of the thermodynamic driving force for elimination of H2 from molecular complexes is important for the rational design of molecular electrocatalysts, and allows the design of metal complexes of abundant, inexpensive metals rather than precious metals (“Cheap Metals for Noble Tasks”). The rate of H2 evolution can be dramatically accelerated by incorporating pendant amines into diphosphine ligands. These pendant amines in the second coordination sphere function as protons relays, accelerating intramolecular and intermolecular proton transfer reactions. The thermodynamics of hydride transfer from metal hydrides and the acidity of protonated pendant amines (pKa of N-H) contribute to the thermodynamics of elimination of H2; both of the hydricity and acidity can be systematically varied by changing the substituents on the ligands. A series of Ni(II) electrocatalysts with pendant amines have been developed. In addition to the thermochemical considerations, the catalytic rate is strongly influenced by the ability to deliver protons to the correct location of the pendant amine. Protonation of the amine endo to the metal leads to the N-H being positioned appropriately to favor rapid heterocoupling with the M-H. Designing ligands that include proton relays that are properly positioned and thermodynamically tuned is a key principle for molecular electrocatalysts for H2 production as well as for other multi-proton, multi-electron reactions important for energy conversions. The research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Pacific Northwest National Laboratory is operated by Battelle for DOE.

  12. Bioengineering and Coordination of Regulatory Networks and Intracellular Complexes to Maximize Hydrogen Production by Phototrophic Microorganisms

    SciTech Connect (OSTI)

    Tabita, F. Robert [The Ohio State University] [The Ohio State University

    2013-07-30

    In this study, the Principal Investigator, F.R. Tabita has teemed up with J. C. Liao from UCLA. This project's main goal is to manipulate regulatory networks in phototrophic bacteria to affect and maximize the production of large amounts of hydrogen gas under conditions where wild-type organisms are constrained by inherent regulatory mechanisms from allowing this to occur. Unrestrained production of hydrogen has been achieved and this will allow for the potential utilization of waste materials as a feed stock to support hydrogen production. By further understanding the means by which regulatory networks interact, this study will seek to maximize the ability of currently available unrestrained organisms to produce hydrogen. The organisms to be utilized in this study, phototrophic microorganisms, in particular nonsulfur purple (NSP) bacteria, catalyze many significant processes including the assimilation of carbon dioxide into organic carbon, nitrogen fixation, sulfur oxidation, aromatic acid degradation, and hydrogen oxidation/evolution. Moreover, due to their great metabolic versatility, such organisms highly regulate these processes in the cell and since virtually all such capabilities are dispensable, excellent experimental systems to study aspects of molecular control and biochemistry/physiology are available.

  13. Correlating Extent of PtNi Bond Formation with Low-temperature Hydrogenation of Benzene and 1,3-butadiene over Supported Pt/Ni Bimetallic Catalysts

    SciTech Connect (OSTI)

    Lonergan, W.; Vlachos, D; Chen, J

    2010-01-01

    Low-temperature hydrogenation of benzene and 1,3-butadiene on supported Pt/Ni catalysts have been used as probe reactions to correlate hydrogenation activity with the extent of Pt-Ni bimetallic bond formation. Pt/Ni bimetallic and Pt and Ni monometallic catalysts were supported on {gamma}-Al{sub 2}O{sub 3} using incipient wetness impregnation. Two sets of bimetallic catalysts were synthesized: one set to study the effect of metal atomic ratio and the other to study the effect of impregnation sequence. Fourier transform infrared spectroscopy (FTIR) CO adsorption studies were performed to characterize the surface composition of the bimetallic nanoparticles, and transmission electron microscopy (TEM) was utilized to characterize the particle size distribution. Batch reactor studies with FTIR demonstrated that all bimetallic catalysts outperformed monometallic catalysts for both benzene and 1,3-butadiene hydrogenation. Within the two sets of bimetallic catalysts, it was found that catalysts with a smaller Pt:Ni ratio possessed higher hydrogenation activity and that catalysts synthesized using co-impregnation had greater activity than sequentially impregnated catalysts. Extended X-ray absorption fine structure (EXAFS) measurements were performed in order to verify the extent of Pt-Ni bimetallic bond formation, which was found to correlate with the hydrogenation activity.

  14. hydrogen

    National Nuclear Security Administration (NNSA)

    3%2A en Cheaper catalyst may lower fuel costs for hydrogen-powered cars http:www.nnsa.energy.govblogcheaper-catalyst-may-lower-fuel-costs-hydrogen-powered-cars

  15. hydrogen

    National Nuclear Security Administration (NNSA)

    3%2A en Cheaper catalyst may lower fuel costs for hydrogen-powered cars http:nnsa.energy.govblogcheaper-catalyst-may-lower-fuel-costs-hydrogen-powered-cars

  16. Encapsulation of Protonated Diamines in a Water-Soluble Chiral, Supramolecular Assembly Allows for Measurement of Hydrogen-Bond Breaking Followed by Nitrogen Inversion/Rotation (NIR)

    SciTech Connect (OSTI)

    Meux, Susan C.; Pluth, Michael D.; Bergman, Robert G.; Raymond, Kenneth N.

    2007-09-19

    Amine nitrogen inversion, difficult to observe in aqueous solution, is followed in a chiral, supramolecular host molecule with purely-rotational T-symmetry that reduces the local symmetry of encapsulated monoprotonated diamines and enables the observation and quantification of {Delta}G{double_dagger} for the combined hydrogen-bond breaking and nitrogen inversion rotation (NIR) process. Free energies of activation for the combined hydrogen-bond breaking and NIR process inside of the chiral assembly were determined by the NMR coalescence method. Activation parameters for ejection of the protonated amines from the assembly confirm that the NIR process responsible for the coalescence behavior occurs inside of the assembly rather than by a guest ejection/NIR/re-encapsulation mechanism. For one of the diamines, N,N,N{prime},N{prime}-tetramethylethylenediamine (TMEDA), the relative energy barriers for the hydrogen-bond breaking and NIR process were calculated at the G3(MP2)//B3LYP/6-31++G(d,p) level of theory, and these agreed well with the experimental data.

  17. The effect of hydrogen bonding on torsional dynamics: A combined far-infrared jet and matrix isolation study of methanol dimer

    SciTech Connect (OSTI)

    Kollipost, F.; Heger, M.; Suhm, M. A.; Andersen, J.; Mahler, D. W.; Wugt Larsen, R.; Heimdal, J.

    2014-11-07

    The effect of strong intermolecular hydrogen bonding on torsional degrees of freedom is investigated by far-infrared absorption spectroscopy for different methanol dimer isotopologues isolated in supersonic jet expansions or embedded in inert neon matrices at low temperatures. For the vacuum-isolated and Ne-embedded methanol dimer, the hydrogen bond OH librational mode of the donor subunit is finally observed at ?560 cm{sup ?1}, blue-shifted by more than 300 cm{sup ?1} relative to the OH torsional fundamental of the free methanol monomer. The OH torsional mode of the acceptor embedded in neon is observed at ?286 cm{sup ?1}. The experimental findings are held against harmonic predictions from local coupled-cluster methods with single and double excitations and a perturbative treatment of triple excitations [LCCSD(T)] and anharmonic. VPT2 corrections at canonical MP2 and density functional theory (DFT) levels in order to quantify the contribution of vibrational anharmonicity for this important class of intermolecular hydrogen bond vibrational motion.

  18. A series of Cd(II) complexes with {pi}-{pi} stacking and hydrogen bonding interactions: Structural diversities by varying the ligands

    SciTech Connect (OSTI)

    Wang Xiuli; Zhang Jinxia; Liu Guocheng; Lin Hongyan

    2011-02-15

    Seven new Cd(II) complexes consisting of different phenanthroline derivatives and organic acid ligands, formulated as [Cd(PIP){sub 2}(dnba){sub 2}] (1), [Cd(PIP)(ox)].H{sub 2}O (2), [Cd(PIP)(1,4-bdc)(H{sub 2}O)].4H{sub 2}O (3), [Cd(3-PIP){sub 2}(H{sub 2}O){sub 2}].4H{sub 2}O (4), [Cd{sub 2}(3-PIP){sub 4}(4,4'-bpdc)(H{sub 2}O){sub 2}].5H{sub 2}O (5), [Cd(3-PIP)(nip)(H{sub 2}O)].H{sub 2}O (6), [Cd{sub 2}(TIP){sub 4}(4,4'-bpdc)(H{sub 2}O){sub 2}].3H{sub 2}O (7) (PIP=2-phenylimidazo[4,5-f]1,10-phenanthroline, 3-PIP=2-(3-pyridyl)imidazo[4,5-f]1,10-phenanthroline, TIP=2-(2-thienyl)imidazo[4,5-f]1,10-phenanthroline, Hdnba=3,5-dinitrobenzoic acid, H{sub 2}ox=oxalic acid, 1,4-H{sub 2}bdc=benzene-1,4-dicarboxylic acid, 4,4'-H{sub 2}bpdc=biphenyl-4,4'-dicarboxylic acid, H{sub 2}nip=5-nitroisophthalic acid) have been synthesized under hydrothermal conditions. Complexes 1 and 4 possess mononuclear structures; complexes 5 and 7 are isostructural and have dinuclear structures; complexes 2 and 3 feature 1D chain structures; complex 6 contains 1D double chain, which are further extended to a 3D supramolecular structure by {pi}-{pi} stacking and hydrogen bonding interactions. The N-donor ligands with extended {pi}-system and organic acid ligands play a crucial role in the formation of the final supramolecular frameworks. Moreover, thermal properties and fluorescence of 1-7 are also investigated. -- Graphical abstract: Seven new supramolecular architectures have been successfully isolated under hydrothermal conditions by reactions of different phen derivatives and Cd(II) salts together with organic carboxylate anions auxiliary ligands. Display Omitted Research highlights: {yields} Complexes 1-7 are 0D or 1D polymeric structure, the {pi}-{pi} stacking and H-bonding interactions extend the complexes into 3D supramolecular network. To our knowledge, systematic study on {pi}-{pi} stacking and H-bonding interactions in cadmium(II) complexes are still limited. {yields} The structural

  19. Quantitative Tools for Dissection of Hydrogen-Producing Metabolic Networks-Final Report

    SciTech Connect (OSTI)

    Rabinowitz, Joshua D.; Dismukes, G.Charles.; Rabitz, Herschel A.; Amador-Noguez, Daniel

    2012-10-19

    During this project we have pioneered the development of integrated experimental-computational technologies for the quantitative dissection of metabolism in hydrogen and biofuel producing microorganisms (i.e. C. acetobutylicum and various cyanobacteria species). The application of these new methodologies resulted in many significant advances in the understanding of the metabolic networks and metabolism of these organisms, and has provided new strategies to enhance their hydrogen or biofuel producing capabilities. As an example, using mass spectrometry, isotope tracers, and quantitative flux-modeling we mapped the metabolic network structure in C. acetobutylicum. This resulted in a comprehensive and quantitative understanding of central carbon metabolism that could not have been obtained using genomic data alone. We discovered that biofuel production in this bacterium, which only occurs during stationary phase, requires a global remodeling of central metabolism (involving large changes in metabolite concentrations and fluxes) that has the effect of redirecting resources (carbon and reducing power) from biomass production into solvent production. This new holistic, quantitative understanding of metabolism is now being used as the basis for metabolic engineering strategies to improve solvent production in this bacterium. In another example, making use of newly developed technologies for monitoring hydrogen and NAD(P)H levels in vivo, we dissected the metabolic pathways for photobiological hydrogen production by cyanobacteria Cyanothece sp. This investigation led to the identification of multiple targets for improving hydrogen production. Importantly, the quantitative tools and approaches that we have developed are broadly applicable and we are now using them to investigate other important biofuel producers, such as cellulolytic bacteria.

  20. Binding of the Respiratory Chain Inhibitor Antimycin to theMitochondrial bc1 Complex: A New Crystal Structure Reveals an AlteredIntramolecular Hydrogen-Bonding Pattern

    SciTech Connect (OSTI)

    Huang, Li-shar; Cobessi, David; Tung, Eric Y.; Berry, Edward A.

    2005-05-10

    Antimycin A (antimycin), one of the first known and most potent inhibitors of the mitochondrial respiratory chain, binds to the quinone reduction site of the cytochrome bc1 complex.Structure-activity-relationship studies have shown that the N-formylamino-salicyl-amide group is responsible for most of the binding specificity, and suggested that a low pKa for the phenolic OH group and an intramolecular H-bond between that OH and the carbonyl O of the salicylamide linkage are important. Two previous X-ray structures of antimycin bound to vertebrate bc1 complex gave conflicting results. A new structure reported here of the bovine mitochondrial bc1 complex at 2.28Angstrom resolution with antimycin bound, allows us for the first time to reliably describe the binding of antimycin and shows that the intramolecular hydrogen bond described in solution and in the small-molecule structure is replaced by one involving the NH rather than carbonyl O of the amide linkage, with rotation of the amide group relative to the aromatic ring. The phenolic OH and formylamino N form H-bonds with conserved Asp228 of cyt b, and the formylamino O H-bonds via a water molecule to Lys227. A strong density the right size and shape for a diatomic molecule is found between the other side of the dilactone ring and the alpha-A helix.

  1. N-(N-[2-(3,5-Difluorophenyl)acetyl]-(S)-alanyl)-(S)-phenylglycine tert-butyl ester (DAPT): an inhibitor of γ-secretase, revealing fine electronic and hydrogen-bonding features

    SciTech Connect (OSTI)

    Czerwinski, Andrzej; Valenzuela, Francisco; Afonine, Pavel; Dauter, Miroslawa; Dauter, Zbigniew

    2010-12-01

    The title compound, C{sub 23}H{sub 26}F{sub 2}N{sub 2}O{sub 4}, is a dipeptidic inhibitor of γ-secretase, one of the enzymes involved in Alzheimer’s dis@@ease. The mol@@ecule adopts a compact conformation, without intra@@molecular hydrogen bonds. In the crystal structure, one of the amide N atoms forms the only inter@@molecular N—H⋯O hydrogen bond; the second amide N atom does not form hydrogen bonds. High-resolution synchrotron diffraction data permitted the unequivocal location and refinement without restraints of all H atoms, and the identification of the characteristic shift of the amide H atom engaged in the hydrogen bond from its ideal position, resulting in a more linear hydrogen bond. Significant residual densities for bonding electrons were revealed after the usual SHELXL refinement, and modeling of these features as additional inter@@atomic scatterers (IAS) using the program PHENIX led to a significant decrease in the R factor from 0.0411 to 0.0325 and diminished the r.m.s. deviation level of noise in the final difference Fourier map from 0.063 to 0.037 e Å{sup −3}.

  2. On the protonation states, hydrogen bonding and catalytic mechanism of family 11 glycosidases: Direct visualization with neutrons

    SciTech Connect (OSTI)

    Fisher, Suzanne Zoe; Graham, David E.; Hanson, Leif; Kovalevskyi, Andrii Y.; Langan, Paul; Parks, Jerry M.; Wan, Qun; Ostermann, Andreas; Schrader, Tobias

    2015-10-06

    Most enzymatic reactions involve hydrogen or proton transfer among the enzyme, substrate, and water at physiological pH. Thus, enzyme catalysis cannot be fully understood without accurate mapping of hydrogen atom positions in these macromolecular catalysts. Direct information on the location of hydrogen atoms can be obtained using neutron crystallography. We used neutron crystallography and biomolecular simulation to characterize the initial stage of the glycoside hydrolysis reaction catalyzed by a family 11 glycoside hydrolase. We provide evidence that the catalytic glutamate residue alternates between two conformations bearing different basicities, first to obtain a proton from the bulk solvent, and then to deliver it to the glycosidic oxygen to initiate the hydrolysis reaction.

  3. In situ ultra-small-angle X-ray scattering study under uniaxial stretching of colloidal crystals prepared by silica nanoparticles bearing hydrogen-bonding polymer grafts

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ishige, Ryohei; Williams, Gregory A.; Higaki, Yuji; Ohta, Noboru; Sato, Masugu; Takahara, Atsushi; Guan, Zhibin

    2016-04-19

    A molded film of single-component polymer-grafted nanoparticles (SPNP), consisting of a spherical silica core and densely grafted polymer chains bearing hydrogen-bonding side groups capable of physical crosslinking, was investigated byin situultra-small-angle X-ray scattering (USAXS) measurement during a uniaxial stretching process. Static USAXS revealed that the molded SPNP formed a highly oriented twinned face-centered cubic (f.c.c.) lattice structure with the [11-1] plane aligned nearly parallel to the film surface in the initial state. Structural analysis ofin situUSAXS using a model of uniaxial deformation induced by rearrangement of the nanoparticles revealed that the f.c.c. lattice was distorted in the stretching direction inmore » proportion to the macroscopic strain until the strain reached 35%, and subsequently changed into other f.c.c. lattices with different orientations. The lattice distortion and structural transition behavior corresponded well to the elastic and plastic deformation regimes, respectively, observed in the stress–strain curve. The attractive interaction of the hydrogen bond is considered to form only at the top surface of the shell and then plays an effective role in cross-linking between nanoparticles. The rearrangement mechanism of the nanoparticles is well accounted for by a strong repulsive interaction between the densely grafted polymer shells of neighboring particles.« less

  4. Joint neutron crystallographic and NMR solution studies of Tyr residue ionization and hydrogen bonding: Implications for enzyme-mediated proton transfer

    SciTech Connect (OSTI)

    Michalczyk, Ryszard; Unkefer, Clifford J.; Bacik, John -Paul; Schrader, Tobias E.; Ostermann, Andreas; Kovalevsky, Andrey Y.; McKenna, Robert; Fisher, Suzanne Zoe

    2015-05-05

    Proton transfer is a fundamental mechanism at the core of many enzyme-catalyzed reactions. It is also exquisitely sensitive to a number of factors, including pH, electrostatics, proper active-site geometry, and chemistry. Carbonic anhydrase has evolved a fast and efficient way to conduct protons through a combination of hydrophilic amino acid side chains that coordinate a highly ordered H-bonded water network. This study uses a powerful approach, combining NMR solution studies with neutron protein crystallography, to determine the effect of pH and divalent cations on key residues involved in proton transfer in human carbonic anhydrase. Lastly, the results have broad implications for our understanding of proton transfer and how subtle changes in ionization and H-bonding interactions can modulate enzyme catalysis.

  5. Joint neutron crystallographic and NMR solution studies of Tyr residue ionization and hydrogen bonding: Implications for enzyme-mediated proton transfer

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Michalczyk, Ryszard; Unkefer, Clifford J.; Bacik, John -Paul; Schrader, Tobias E.; Ostermann, Andreas; Kovalevsky, Andrey Y.; McKenna, Robert; Fisher, Suzanne Zoe

    2015-05-05

    Proton transfer is a fundamental mechanism at the core of many enzyme-catalyzed reactions. It is also exquisitely sensitive to a number of factors, including pH, electrostatics, proper active-site geometry, and chemistry. Carbonic anhydrase has evolved a fast and efficient way to conduct protons through a combination of hydrophilic amino acid side chains that coordinate a highly ordered H-bonded water network. This study uses a powerful approach, combining NMR solution studies with neutron protein crystallography, to determine the effect of pH and divalent cations on key residues involved in proton transfer in human carbonic anhydrase. Lastly, the results have broad implicationsmore » for our understanding of proton transfer and how subtle changes in ionization and H-bonding interactions can modulate enzyme catalysis.« less

  6. On the protonation states, hydrogen bonding and catalytic mechanism of family 11 glycosidases: Direct visualization with neutrons

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Fisher, Suzanne Zoe; Graham, David E.; Hanson, Leif; Kovalevskyi, Andrii Y.; Langan, Paul; Parks, Jerry M.; Wan, Qun; Ostermann, Andreas; Schrader, Tobias

    2015-10-06

    Most enzymatic reactions involve hydrogen or proton transfer among the enzyme, substrate, and water at physiological pH. Thus, enzyme catalysis cannot be fully understood without accurate mapping of hydrogen atom positions in these macromolecular catalysts. Direct information on the location of hydrogen atoms can be obtained using neutron crystallography. We used neutron crystallography and biomolecular simulation to characterize the initial stage of the glycoside hydrolysis reaction catalyzed by a family 11 glycoside hydrolase. We provide evidence that the catalytic glutamate residue alternates between two conformations bearing different basicities, first to obtain a proton from the bulk solvent, and then tomore » deliver it to the glycosidic oxygen to initiate the hydrolysis reaction.« less

  7. Engineering and Coordination of Regulatory Networks and Intracellular Complexes to Maximize Hydrogen Production by Phototrophic Microorganisms

    SciTech Connect (OSTI)

    James C. Liao

    2012-05-22

    This project is a collaboration with F. R. Tabita of Ohio State. Our major goal is to understand the factors and regulatory mechanisms that influence hydrogen production. The organisms to be utilized in this study, phototrophic microorganisms, in particular nonsulfur purple (NSP) bacteria, catalyze many significant processes including the assimilation of carbon dioxide into organic carbon, nitrogen fixation, sulfur oxidation, aromatic acid degradation, and hydrogen oxidation/evolution. Our part of the project was to develop a modeling technique to investigate the metabolic network in connection to hydrogen production and regulation. Organisms must balance the pathways that generate and consume reducing power in order to maintain redox homeostasis to achieve growth. Maintaining this homeostasis in the nonsulfur purple photosynthetic bacteria is a complex feat with many avenues that can lead to balance, as these organisms possess versatile metabolic capabilities including anoxygenic photosynthesis, aerobic or anaerobic respiration, and fermentation. Growth is achieved by using H{sub 2} as an electron donor and CO{sub 2} as a carbon source during photoautotrophic and chemoautotrophic growth, where CO{sub 2} is fixed via the Calvin-Benson-Bassham (CBB) cycle. Photoheterotrophic growth can also occur when alternative organic carbon compounds are utilized as both the carbon source and electron donor. Regardless of the growth mode, excess reducing equivalents generated as a result of oxidative processes, must be transferred to terminal electron acceptors, thus insuring that redox homeostasis is maintained in the cell. Possible terminal acceptors include O{sub 2}, CO{sub 2}, organic carbon, or various oxyanions. Cells possess regulatory mechanisms to balance the activity of the pathways which supply energy, such as photosynthesis, and those that consume energy, such as CO{sub 2} assimilation or N{sub 2} fixation. The major route for CO{sub 2} assimilation is the CBB

  8. NanoCapillary Network Proton Conducting Membranes for High Temperature Hydrogen/Air Fuel Cells

    SciTech Connect (OSTI)

    Pintauro, Peter

    2012-07-09

    The objective of this proposal is to fabricate and characterize a new class of NanoCapillary Network (NCN) proton conducting membranes for hydrogen/air fuel cells that operate under high temperature, low humidity conditions. The membranes will be intelligently designed, where a high density interconnecting 3-D network of nm-diameter electrospun proton conducting polymer fibers is embedded in an inert (uncharged) water/gas impermeable polymer matrix. The high density of fibers in the resulting mat and the high ion-exchange capacity of the fiber polymer will ensure high proton conductivity. To further enhance water retention, molecular silica will be added to the sulfonated polymer fibers. The uncharged matrix material will control water swelling of the high ion-exchange capacity proton conducting polymer fibers and will impart toughness to the final nanocapillary composite membrane. Thus, unlike other fuel cell membranes, the role of the polymer support matrix will be decoupled from that of the proton-conducting channels. The expected final outcome of this 5-year project is the fabrication of fuel cell membranes with properties that exceed the DOE’s technical targets, in particular a proton conductivity of 0.1 S/cm at a temperature less than or equal to120°C and 25-50% relative humidity.

  9. Bonded semiconductor substrate

    DOE Patents [OSTI]

    Atwater, Jr.; Harry A. , Zahler; James M.

    2010-07-13

    Ge/Si and other nonsilicon film heterostructures are formed by hydrogen-induced exfoliation of the Ge film which is wafer bonded to a cheaper substrate, such as Si. A thin, single-crystal layer of Ge is transferred to Si substrate. The bond at the interface of the Ge/Si heterostructures is covalent to ensure good thermal contact, mechanical strength, and to enable the formation of an ohmic contact between the Si substrate and Ge layers. To accomplish this type of bond, hydrophobic wafer bonding is used, because as the invention demonstrates the hydrogen-surface-terminating species that facilitate van der Waals bonding evolves at temperatures above 600.degree. C. into covalent bonding in hydrophobically bound Ge/Si layer transferred systems.

  10. Optical and electrochemical properties of hydrogen-bondedphenol...

    Office of Scientific and Technical Information (OSTI)

    properties of hydrogen-bonded phenol-pyrrolidino60fullerenes Citation Details In-Document Search Title: Optical and electrochemical properties of hydrogen-bonded ...

  11. Hydrogen interaction kinetics of Ge dangling bonds at the Si{sub 0.25}Ge{sub 0.75}/SiO{sub 2} interface

    SciTech Connect (OSTI)

    Stesmans, A. Nguyen Hoang, T.; Afanas'ev, V. V.

    2014-07-28

    The hydrogen interaction kinetics of the GeP{sub b1} defect, previously identified by electron spin resonance (ESR) as an interfacial Ge dangling bond (DB) defect occurring in densities ?7??10{sup 12}?cm{sup ?2} at the SiGe/SiO{sub 2} interfaces of condensation grown (100)Si/a-SiO{sub 2}/Ge{sub 0.75}Si{sub 0.25}/a-SiO{sub 2} structures, has been studied as function of temperature. This has been carried out, both in the isothermal and isochronal mode, through defect monitoring by capacitance-voltage measurements in conjunction with ESR probing, where it has previously been demonstrated the defects to operate as negative charge traps. The work entails a full interaction cycle study, comprised of analysis of both defect passivation (pictured as GeP{sub b1}-H formation) in molecular hydrogen (?1?atm) and reactivation (GeP{sub b1}-H dissociation) in vacuum. It is found that both processes can be suitably described separately by the generalized simple thermal (GST) model, embodying a first order interaction kinetics description based on the basic chemical reactions GeP{sub b1}?+?H{sub 2}???GeP{sub b1}H?+?H and GeP{sub b1}H???GeP{sub b1}?+?H, which are found to be characterized by the average activation energies E{sub f}?=?1.44??0.04?eV and E{sub d}?=?2.23??0.04?eV, and attendant, assumedly Gaussian, spreads ?E{sub f}?=?0.20??0.02?eV and ?E{sub d}?=?0.15??0.02?eV, respectively. The substantial spreads refer to enhanced interfacial disorder. Combination of the separately inferred kinetic parameters for passivation and dissociation results in the unified realistic GST description that incorporates the simultaneous competing action of passivation and dissociation, and which is found to excellently account for the full cycle data. For process times t{sub a}???35?min, it is found that even for the optimum treatment temperature ?380?C, only ?60% of the GeP{sub b1} system can be electrically silenced, still far remote from device grade level. This ineffectiveness is

  12. Temperature dependent structural variation from 2D supramolecular network to 3D interpenetrated metal–organic framework: In situ cleavage of S–S and C–S bonds

    SciTech Connect (OSTI)

    Ugale, Bharat; Singh, Divyendu; Nagaraja, C.M.

    2015-03-15

    Two new Zn(II)–organic compounds, [Zn(muco)(dbds){sub 2}(H{sub 2}O){sub 2}] (1) and [Zn(muco)(dbs)] (2) (where, muco=trans, trans-muconate dianion, dbds=4,4′-dipyridyldisulfide and dbs=4,4′-dipyridylsulfide) have been synthesized from same precursors but at two different temperatures. Both the compounds have been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, IR spectroscopy, thermal analysis and photoluminescence studies. Compound 1 prepared at room temperature possesses a molecular structure extended to 2D supramolecular network through (H–O…H) hydrogen-bonding interactions. Compound 2, obtained at high temperature (100 °C) shows a 3-fold interpenetrating 3D framework constituted by an in situ generated dbs linker by the cleavage of S–S and C–S bonds of dbds linker. Thus, the influence of reaction temperature on the formation of two structural phases has been demonstrated. Both 1 and 2 exhibit ligand based luminescence emission owing to n→π⁎ and π→π⁎ transitions and also high thermal stabilities. - Graphical abstract: The influence of temperature on the formation of two structural phases, a 2D supramolecular network and a 3D 3-fold interpenetrating framework has been demonstrated and their luminescence emission is measured. - Highlights: • Two new Zn(II)–organic compounds were synthesized by tuning reaction temperatures. • Temperature induced in situ generation of dbs linker has been observed. • The compounds exhibit high thermal stability and luminescence emission properties. • The effect of temperature on structure, dimension and topology has been presented.

  13. Hydrogen-based electrochemical energy storage

    DOE Patents [OSTI]

    Simpson, Lin Jay

    2013-08-06

    An energy storage device (100) providing high storage densities via hydrogen storage. The device (100) includes a counter electrode (110), a storage electrode (130), and an ion conducting membrane (120) positioned between the counter electrode (110) and the storage electrode (130). The counter electrode (110) is formed of one or more materials with an affinity for hydrogen and includes an exchange matrix for elements/materials selected from the non-noble materials that have an affinity for hydrogen. The storage electrode (130) is loaded with hydrogen such as atomic or mono-hydrogen that is adsorbed by a hydrogen storage material such that the hydrogen (132, 134) may be stored with low chemical bonding. The hydrogen storage material is typically formed of a lightweight material such as carbon or boron with a network of passage-ways or intercalants for storing and conducting mono-hydrogen, protons, or the like. The hydrogen storage material may store at least ten percent by weight hydrogen (132, 134) at ambient temperature and pressure.

  14. Hydrogen scavengers

    DOE Patents [OSTI]

    Carroll, David W.; Salazar, Kenneth V.; Trkula, Mitchell; Sandoval, Cynthia W.

    2002-01-01

    There has been invented a codeposition process for fabricating hydrogen scavengers. First, a .pi.-bonded allylic organometallic complex is prepared by reacting an allylic transition metal halide with an organic ligand complexed with an alkali metal; and then, in a second step, a vapor of the .pi.-bonded allylic organometallic complex is combined with the vapor of an acetylenic compound, irradiated with UV light, and codeposited on a substrate.

  15. Integrating large-scale functional genomics data to dissect metabolic networks for hydrogen production

    SciTech Connect (OSTI)

    Harwood, Caroline S

    2012-12-17

    The goal of this project is to identify gene networks that are critical for efficient biohydrogen production by leveraging variation in gene content and gene expression in independently isolated Rhodopseudomonas palustris strains. Coexpression methods were applied to large data sets that we have collected to define probabilistic causal gene networks. To our knowledge this a first systems level approach that takes advantage of strain-to strain variability to computationally define networks critical for a particular bacterial phenotypic trait.

  16. An Alternative Low-Cost Process for Deposition of MCrAlY Bond Coats for Advanced Syngas/Hydrogen Turbine Applications

    SciTech Connect (OSTI)

    Zhang, Ying

    2015-09-11

    The objective of this project was to develop and optimize MCrAlY bond coats for syngas/hydrogen turbine applications using a low-cost electrolytic codeposition process. Prealloyed CrAlY-based powders were codeposited into a metal matrix of Ni, Co or Ni-Co during the electroplating process, and a subsequent post-deposition heat treatment converted it to the MCrAlY coating. Our research efforts focused on: (1) investigation of the effects of electro-codeposition configuration and parameters on the CrAlY particle incorporation in the NiCo-CrAlY composite coatings; (2) development of the post-deposition heat treating procedure; (3) characterization of coating properties and evaluation of coating oxidation performance; (4) exploration of a sulfurfree electroplating solution; (5) cost analysis of the present electrolytic codeposition process. Different electro-codeposition configurations were investigated, and the rotating barrel system demonstrated the capability of depositing NiCo-CrAlY composite coatings uniformly on the entire specimen surface, with the CrAlY particle incorporation in the range 37-42 vol.%. Post-deposition heat treatment at 1000-1200 °C promoted interdiffusion between the CrAlY particles and the Ni-Co metal matrix, resulting in β/γ’/γ or β/γ’ phases in the heat-treated coatings. The results also indicate that the post-deposition heat treatment should be conducted at temperatures ≤1100 °C to minimize Cr evaporation and outward diffusion of Ti. The electro-codeposited NiCrAlY coatings in general showed lower hardness and surface roughness than thermal spray MCrAlY coatings. Coating oxidation performance was evaluated at 1000-1100 °C in dry and wet air environments. The initial electro-codeposited NiCoCrAlY coatings containing relatively high sulfur did not show good oxidation resistance. After modifications of the coating process, the cleaner NiCoCrAlY coating exhibited good oxidation performance at 1000 °C during the 2,000 1-h cyclic

  17. Insight into methanol synthesis from CO2 hydrogenation on Cu(111): Complex reaction network and the effects of H2O

    SciTech Connect (OSTI)

    Zhao, Yafan; Yang, Yong; Mims, Charles A.; Peden, Charles HF; Li, Jun; Mei, Donghai

    2011-05-31

    Methanol synthesis from CO2 hydrogenation on supported Cu catalysts is of considerable importance in the chemical and energy industries. Although extensive experimental and theoretical efforts have been carried out in the past decades, the most fundamental questions such as the reaction mechanisms and the key reaction intermediates are still in debate. In the present work, a comprehensive reaction network for CO2 hydrogenation to methanol on Cu(111) was studied using periodic density functional theory (DFT) calculations. All of the elementary reaction steps in the reaction network were identified in an unbiased way with the dimer method. Our calculation results show that methanol synthesis from direct hydrogenation of formate on Cu(111) is not feasible due to the high activation barriers for some of the elementary steps. Instead, we find that CO2 hydrogenation to hydrocarboxyl (trans-COOH) is kinetically more favorable than formate in the presence of H2O via a unique proton transfer mechanism. The trans-COOH is then converted into hydroxymethylidyne (COH) via dihydroxycarbene (COHOH) intermediates, followed by three consecutive hydrogenation steps to form hydroxymethylene (HCOH), hydroxymethyl (H2COH), and methanol. This is consistent with recent experimental observations [1], which indicate that direct hydrogenation of formate will not produce methanol under dry hydrogen conditions. Thus, both experiment and computational modeling clearly demonstrate the important role of trace amounts of water in methanol synthesis from CO2 hydrogenation on Cu catalysts. The proposed methanol synthesis route on Cu(111) not only provides new insights into methanol synthesis chemistry, but also demonstrates again that spectroscopically observed surface species are often not critical reaction intermediates but rather spectator species. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  18. Crystal structure and characterization of the novel NH{sup +} Midline-Horizontal-Ellipsis N hydrogen bonded polar crystal [NH{sub 2}(CH{sub 2}){sub 4}NH][BF{sub 4}

    SciTech Connect (OSTI)

    Wojtas, M.; Gagor, A.; Czupinski, O.; Medycki, W.; Jakubas, R.

    2012-03-15

    Dielectric properties and phase transitions of the piperazinium tetrafluoroborate ([NH{sub 2}(CH{sub 2}){sub 4}NH][BF{sub 4}], abbreviated as PFB) crystal are related to the one-dimensional arrangement of the cations linked by the bistable NH{sup +} Midline-Horizontal-Ellipsis N hydrogen bonds and molecular motions of the [BF{sub 4}]{sup -} units. The crystal structure of [NH{sub 2}(CH{sub 2}){sub 4}NH][BF{sub 4}] is monoclinic at room temperature with the polar space group Pn. The polar/acentric properties of the room temperature phase IV have been confirmed by the piezoelectric and pyroelectric measurements. DSC measurements show that the compound undergoes three first-order structural phase transitions: at 421/411 K (heating/cooling), at 386/372 K and at 364/349 K. {sup 1}H and {sup 19}F NMR measurements indicate the reorientational motions of [BF{sub 4}]{sup -} anions and piperazinium(+) cations as well as the proton motion in the hydrogen-bonded chains of piperazine along the [001] direction. Over the phase I the isotropic reorientational motions or even self-diffusion of the cations and anions are expected. The conductivity measurements in the vicinity of the II-I PT indicate a superionic phase over the phase I. - Graphical abstract: It must be emphasized that the titled compound represents the first organic-inorganic simple salt containing the single-protonated piperazinium cation which was studied by means of the wide variety of experimental techniques. A survey of Cambridge Structural Database (CSD version 5.32 (November 2010) and updates (May 2011)) for structure containing the piperazinium cations yields 248 compounds with the doubly protonated piperazinium(2+) cations and only eight compounds with the singly protonated piperazinium(+) cations. Among these structures only one is the hybrid organic-inorganic material. This is piperazinium nitrate characterized structurally. The crystal packing of [NH{sub 2}(CH{sub 2}){sub 4}NH][BF{sub 4}], phase IV. The

  19. FINAL TECHNICAL REPORT for grant DE-FG02-93ER14353 ????"Carbon-Hydrogen Bond Functionalization Catalyzed by Transition Metal Systems"

    SciTech Connect (OSTI)

    Alan S. Goldman

    2012-05-21

    Alkanes are our most abundant organic resource but are highly resistant to selective chemical transformations. Alkenes (olefins) by contrast are the single most versatile class of molecules for selective transformations, and are intermediates in virtually every petrochemical process as well as a vast range of commodity and fine chemical processes. Over the course of this project we have developed the most efficient catalysts to date for the selective conversion of alkanes to give olefins, and have applied these catalysts to other dehydrogenation reactions. We have also developed some of the first efficient catalysts for carbonylation of alkanes and arenes to give aldehydes. The development of these catalysts has been accompanied by elucidation of the mechanism of their operation and the factors controlling the kinetics and thermodynamics of C-H bond activation and other individual steps of the catalytic cycles. This fundamental understanding will allow the further improvement of these catalysts, as well as the development of the next generation of catalysts for the functionalization of alkanes and other molecules containing C-H bonds.

  20. Hydrogen Infrastructure Market Readiness: Opportunities and Potential...

    Broader source: Energy.gov (indexed) [DOE]

    Recent progress with fuel cell electric vehicles (FCEVs) has focused attention on hydrogen ... a sufficient network of hydrogen stations to support large-volume vehicle deployments. ...

  1. International Hydrogen Infrastructure Challenges Workshop Summary

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Webinar: International Hydrogen Infrastructure Challenges Workshop Summary - NOW, NEDO and ... of Intent to expand the network of hydrogen filling stations in Germany * overall ...

  2. BREAKING BOND

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    BREAKING BOND the Can chemistry help unbind us from fossil fuels? 1663 July 2016 21 When ... Their goal: to use chemistry to construct gasoline-like hydrocarbons from plant sugars. ...

  3. Hydrogen cluster/network in tobermorite as studied by multiple-quantum spin counting {sup 1}H NMR

    SciTech Connect (OSTI)

    Mogami, Yuuki; Yamazaki, Satoru; Matsuno, Shinya; Matsui, Kunio; Noda, Yasuto; Takegoshi, K.

    2014-12-15

    Proton multiple-quantum (MQ) spin-counting experiment has been employed to study arrangement of hydrogen atoms in 9 Å/11 Å natural/synthetic tobermorites. Even though all tobermorite samples give similar characterless, broad static-powder {sup 1}H NMR spectra, their MQ spin-counting spectra are markedly different; higher quanta in 11 Å tobermorite do not grow with the MQ excitation time, while those in 9 Å one do. A statistical analysis of the MQ results recently proposed [26] is applied to show that hydrogens align in 9 Å tobermorite one dimensionally, while in 11 Å tobermorite they exist as a cluster of 5–8 hydrogen atoms.

  4. Ion aggregation in high salt solutions: Ion network versus ion cluster

    SciTech Connect (OSTI)

    Kim, Seongheun; Kim, Heejae; Choi, Jun-Ho; Cho, Minhaeng

    2014-09-28

    The critical aggregation phenomena are ubiquitous in many self-assembling systems. Ions in high salt solutions could also spontaneously form larger ion aggregates, but their effects on hydrogen-bond structures in water have long been controversial. Here, carrying out molecular dynamics (MD) simulation studies of high salt solutions and comparing the MD simulation results with infrared absorption and pump-probe spectroscopy of OD stretch mode of HDO in highly concentrated salt solutions and {sup 13}C-NMR chemical shift of S{sup 13}CN{sup ?} in KSCN solutions, we find evidence on the onset of ion aggregate and large-scale ion-ion network formation that concomitantly breaks water hydrogen-bond structure in certain salt solutions. Despite that these experimental results cannot provide direct evidence on the three-dimensional morphological structures of ion aggregates, they serve as reference data for verifying MD simulation methods. The MD results suggest that disrupted water hydrogen-bond network is intricately intertwined with ion-ion network. This further shows morphological variation of ion aggregate structures from ion cluster to ion network in high salt solutions that are interrelated to the onset of macroscopic aggregate formation and the water hydrogen-bond structure making and breaking processes induced by Hofmeister ions.

  5. Polymer system for gettering hydrogen

    DOE Patents [OSTI]

    Shepodd, Timothy Jon; Whinnery, LeRoy L.

    2000-01-01

    A novel composition comprising organic polymer molecules having carbon-carbon double bonds, for removing hydrogen from the atmosphere within enclosed spaces. Organic polymers molecules containing carbon-carbon double bonds throughout their structures, preferably polybutadiene, polyisoprene and derivatives thereof, intimately mixed with an insoluble catalyst composition, comprising a hydrogenation catalyst and a catalyst support, preferably Pd supported on carbon, provide a hydrogen getter composition useful for removing hydrogen from enclosed spaces even in the presence of contaminants such as common atmospheric gases, water vapor, carbon dioxide, ammonia, oil mists, and water. The hydrogen getter composition disclosed herein is particularly useful for removing hydrogen from enclosed spaces containing potentially explosive mixtures of hydrogen and oxygen.

  6. Polymer formulations for gettering hydrogen

    DOE Patents [OSTI]

    Shepodd, Timothy Jon; Whinnery, LeRoy L.

    1998-11-17

    A novel composition comprising organic polymer molecules having carbon-carbon double bonds, for removing hydrogen from the atmosphere within enclosed spaces. Organic polymers molecules containing carbon-carbon double bonds throughout their structures, preferably polybutadiene, polyisoprene and derivatives thereof, intimately mixed with an insoluble catalyst composition, comprising a hydrogenation catalyst and a catalyst support, preferably Pd supported on carbon, provide a hydrogen getter composition useful for removing hydrogen from enclosed spaces even in the presence of contaminants such as common atmospheric gases, water vapor, carbon dioxide, ammonia, oil mists, and water. The hydrogen getter composition disclosed herein is particularly useful for removing hydrogen from enclosed spaces containing potentially explosive mixtures of hydrogen and oxygen.

  7. Polymer formulations for gettering hydrogen

    DOE Patents [OSTI]

    Shepodd, T.J.; Whinnery, L.L.

    1998-11-17

    A novel composition is described comprising organic polymer molecules having carbon-carbon double bonds, for removing hydrogen from the atmosphere within enclosed spaces. Organic polymers molecules containing carbon-carbon double bonds throughout their structures, preferably polybutadiene, polyisoprene and derivatives thereof, intimately mixed with an insoluble catalyst composition, comprising a hydrogenation catalyst and a catalyst support, preferably Pd supported on carbon, provide a hydrogen getter composition useful for removing hydrogen from enclosed spaces even in the presence of contaminants such as common atmospheric gases, water vapor, carbon dioxide, ammonia, oil mists, and water. The hydrogen getter composition disclosed herein is particularly useful for removing hydrogen from enclosed spaces containing potentially explosive mixtures of hydrogen and oxygen. 1 fig.

  8. Diffusion bonding

    DOE Patents [OSTI]

    Anderson, Robert C.

    1976-06-22

    1. A method for joining beryllium to beryllium by diffusion bonding, comprising the steps of coating at least one surface portion of at least two beryllium pieces with nickel, positioning a coated surface portion in a contiguous relationship with an other surface portion, subjecting the contiguously disposed surface portions to an environment having an atmosphere at a pressure lower than ambient pressure, applying a force upon the beryllium pieces for causing the contiguous surface portions to abut against each other, heating the contiguous surface portions to a maximum temperature less than the melting temperature of the beryllium, substantially uniformly decreasing the applied force while increasing the temperature after attaining a temperature substantially above room temperature, and maintaining a portion of the applied force at a temperature corresponding to about maximum temperature for a duration sufficient to effect the diffusion bond between the contiguous surface portions.

  9. Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ESnet About ESnet Our Mission The Network ESnet History Governance & Policies Career Opportunities ESnet Staff & Org Chart Contact Us Contact Us Technical Assistance: 1 800-33-ESnet (Inside US) 1 800-333-7638 (Inside US) 1 510-486-7600 (Globally) 1 510-486-7607 (Globally) Report Network Problems: trouble@es.net Provide Web Site Feedback: info@es.net About ESnet A Platform for Science Discovery The Energy Sciences Network (ESnet) is a high-performance, unclassified network built to

  10. Communicating Hydrogen: Matching Message with Media

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Communicating Hydrogen: Matching Message with Media Henry Gentenaar, The Media Network Christy Cooper, DOE Hydrogen Program State/Regional Hydrogen and Fuel Cell Initiatives Networking Meeting NHA Annual Hydrogen Conference March 19, 2007 * San Antonio, TX 1 Making the Hydrogen Message "Stick" * We are a communications-based society - Constant stream of information/constant contact * "Supersaturated" - more info than we can process * Information is nothing if it doesn't

  11. Nearly Equivalent Inter- and Intramolecular Hydrogen Bonding...

    Office of Scientific and Technical Information (OSTI)

    DOE Contract Number: AC52-07NA27344 Resource Type: Journal Article Resource Relation: Journal Name: Journal of Physical Chemistry. C; Journal Volume: 116; Journal Issue: 3 ...

  12. Disruption of Hydrogen Bonds between Major Histocompatibility...

    Office of Scientific and Technical Information (OSTI)

    NTerminus Is Not Sufficient to Form a Human Leukocyte Antigen-DM Receptive State of ... NTerminus Is Not Sufficient to Form a Human Leukocyte Antigen-DM Receptive State of ...

  13. Nearly Equivalent Inter- and Intramolecular Hydrogen Bonding...

    Office of Scientific and Technical Information (OSTI)

    Resource Relation: Journal Name: Journal of Physical Chemistry. C; Journal Volume: 116; Journal Issue: 3 Publisher: American Chemical Society Research Org: Lawrence Livermore ...

  14. Hydrogen sensor

    DOE Patents [OSTI]

    Duan, Yixiang; Jia, Quanxi; Cao, Wenqing

    2010-11-23

    A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

  15. Hydrogen Safety Panel | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Panel Hydrogen Safety Panel 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. scs_07_weiner.pdf (1.41 MB) More Documents & Publications Hydrogen Safety: First Responder Education Hydrogen Safety Knowledge Tools NanoCapillary Network Proton Conducting Membranes for High Temperature Hydrogen/Air Fuel Cells

  16. Hydrogenation apparatus

    DOE Patents [OSTI]

    Friedman, Joseph [Encino, CA; Oberg, Carl L [Canoga Park, CA; Russell, Larry H [Agoura, CA

    1981-01-01

    Hydrogenation reaction apparatus comprising a housing having walls which define a reaction zone and conduits for introducing streams of hydrogen and oxygen into the reaction zone, the oxygen being introduced into a central portion of the hydrogen stream to maintain a boundary layer of hydrogen along the walls of the reaction zone. A portion of the hydrogen and all of the oxygen react to produce a heated gas stream having a temperature within the range of from 1100.degree. to 1900.degree. C., while the boundary layer of hydrogen maintains the wall temperature at a substantially lower temperature. The heated gas stream is introduced into a hydrogenation reaction zone and provides the source of heat and hydrogen for a hydrogenation reaction. There also is provided means for quenching the products of the hydrogenation reaction. The present invention is particularly suitable for the hydrogenation of low-value solid carbonaceous materials to provide high yields of more valuable liquid and gaseous products.

  17. Questions and Issues on Hydrogen Pipelines: Pipeline Transmission of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrogen | Department of Energy Questions and Issues on Hydrogen Pipelines: Pipeline Transmission of Hydrogen Questions and Issues on Hydrogen Pipelines: Pipeline Transmission of Hydrogen Pipping of GH2 Pipeline. Background: FG 64 built in 50ies, KP added in 70ies, active mining area over total length hpwgw_questissues_campbell.pdf (1.02 MB) More Documents & Publications Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key Issues Hydrogen Pipeline Discussion EIS-0487:

  18. Hydrogen Behavior

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Efficiency » Vehicles » Hydrogen & Fuel Cells Hydrogen & Fuel Cells Watch this video to find out how fuel cell technology generates clean electricity from hydrogen to power our buildings and transportation-while emitting nothing but water. Learn more about hydrogen and fuel cell technology basics. Fuel cells produce electricity from a number of domestic fuels, including hydrogen and renewables, and can provide power for virtually any application -- from cars and buses to commercial

  19. Hydrogenation process for solid carbonaceous materials

    DOE Patents [OSTI]

    Cox, John L.; Wilcox, Wayne A.

    1979-01-01

    Coal or other solid carbonaceous material is contacted with an organic solvent containing both hydrogen and a transition metal catalyst in solution to hydrogenate unsaturated bonds within the carbonaceous material. This benefaction step permits subsequent pyrolysis or hydrogenolysis of the carbonaceous fuel to form gaseous and liquid hydrocarbon products of increased yield and quality.

  20. Trending: Metal Oxo Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Trending: Metal Oxo Bonds Trending: Metal Oxo Bonds Print Wednesday, 29 May 2013 00:00 Metal oxides are important for scientific and technical applications in a variety of disciplines, including materials science, chemistry, and biology. Highly covalent metal-oxygen multiple bonds (metal oxos) are the building blocks of metal oxides and have a bearing on the oxide's desirable chemical, magnetic, electronic, and thermal properties. The lack of a more sophisticated grasp of bonding in metal oxides

  1. Hydrogen sensor (Patent) | DOEPatents

    Office of Scientific and Technical Information (OSTI)

    Hydrogen sensor Title: Hydrogen sensor A hydrogen sensor for detectingquantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites ...

  2. Hydrogen Storage

    Fuel Cell Technologies Publication and Product Library (EERE)

    This 2-page fact sheet provides a brief introduction to hydrogen storage technologies. Intended for a non-technical audience, it explains the different ways in which hydrogen can be stored, as well a

  3. Hydrogen Analysis

    Broader source: Energy.gov [DOE]

    Presentation on Hydrogen Analysis to the DOE Systems Analysis Workshop held in Washington, D.C. July 28-29, 2004 to discuss and define role of systems analysis in DOE Hydrogen Program.

  4. Hydrogen Safety

    Fuel Cell Technologies Publication and Product Library (EERE)

    This 2-page fact sheet, intended for a non-technical audience, explains the basic properties of hydrogen and provides an overview of issues related to the safe use of hydrogen as an energy carrier.

  5. Polymer formulations for gettering hydrogen

    DOE Patents [OSTI]

    Shepodd, Timothy J.; Even, Jr., William R.

    2000-01-01

    A novel method for preparing a hydrogenation composition comprising organic polymer molecules having carbon--carbon double bonds, for removing hydrogen from the atmosphere within enclosed spaces and particularly from atmospheres within enclosed spaces that contain air, water vapor, oxygen, carbon dioxide or ammonia. The organic polymers molecules containing carbon--carbon double bonds throughout their structures, preferably polybutadiene, polyisoprene and derivatives thereof, intimately mixed with an insoluble noble metal catalyst composition. High molecular weight polymers may be added to the organic polymer/catalyst mixture in order to improve their high temperature performance. The hydrogenation composition is prepared by dispersing the polymers in a suitable solvent, forming thereby a solution suspension, flash-freezing droplets of the solution in a liquid cryogen, freeze-drying the frozen droplets to remove frozen solvent incorporated in the droplets, and recovering the dried powder thus formed.

  6. Hydrogen Scenarios

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    OnLocation, Inc., Energy Systems Consulting 1 Hydrogen Scenarios Presentation to the Hydrogen Delivery Analysis Meeting by Frances Wood OnLocation, Inc. Energy Systems Consulting May 9, 2007 OnLocation, Inc., Energy Systems Consulting 2 Outline * Brief summary of NEMS-H2 model * Representation of Hydrogen Delivery * Hydrogen Demand Sensitivities * Integration and Energy System Impacts - A Carbon Policy Scenario Example OnLocation, Inc., Energy Systems Consulting 3 NEMS-H2 Overview OnLocation,

  7. Bonding thermoplastic polymers

    DOE Patents [OSTI]

    Wallow, Thomas I.; Hunter, Marion C.; Krafcik, Karen Lee; Morales, Alfredo M.; Simmons, Blake A.; Domeier, Linda A.

    2008-06-24

    We demonstrate a new method for joining patterned thermoplastic parts into layered structures. The method takes advantage of case-II permeant diffusion to generate dimensionally controlled, activated bonding layers at the surfaces being joined. It is capable of producing bonds characterized by cohesive failure while preserving the fidelity of patterned features in the bonding surfaces. This approach is uniquely suited to production of microfluidic multilayer structures, as it allows the bond-forming interface between plastic parts to be precisely manipulated at micrometer length scales. The bond enhancing procedure is easily integrated in standard process flows and requires no specialized equipment.

  8. Hydrogen Storage

    SciTech Connect (OSTI)

    2008-11-01

    This 2-page fact sheet provides a brief introduction to hydrogen storage technologies. Intended for a non-technical audience, it explains the different ways in which hydrogen can be stored, as well as the technical challenges and research goals for storing hydrogen on board a vehicle.

  9. Hydrogen Production

    SciTech Connect (OSTI)

    2014-09-01

    This 2-page fact sheet provides a brief introduction to hydrogen production technologies. Intended for a non-technical audience, it explains how different resources and processes can be used to produce hydrogen. It includes an overview of research goals as well as “quick facts” about hydrogen energy resources and production technologies.

  10. Clean Energy Bond Finance Model: Industrial Development Bonds (IDBs) |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Bond Finance Model: Industrial Development Bonds (IDBs) Clean Energy Bond Finance Model: Industrial Development Bonds (IDBs) Overview of industrial development bonds. Author: Clean Energy and Bond Finance Initiative (CE+BFI) Industrial Development Bonds (IDBs) Fact Sheet More Documents & Publications Reduce Risk, Increase Clean Energy: How States and Cities are Using Old Finance Tools to Scale Up a New Industry Clean Energy and Bond Finance Initiative Financing

  11. Reliability of Bonded Interfaces

    Broader source: Energy.gov [DOE]

    2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

  12. Qualified Energy Conservation Bonds (QECBs)

    Broader source: Energy.gov [DOE]

    With tax credit bonds, generally the borrower who issues the bond pays back only the principal of the bond, and the bondholder receives federal tax credits in lieu of the traditional bond interest...

  13. Hydrogenation apparatus

    DOE Patents [OSTI]

    Friedman, J.; Oberg, C. L.; Russell, L. H.

    1981-06-23

    Hydrogenation reaction apparatus is described comprising a housing having walls which define a reaction zone and conduits for introducing streams of hydrogen and oxygen into the reaction zone, the oxygen being introduced into a central portion of the hydrogen stream to maintain a boundary layer of hydrogen along the walls of the reaction zone. A portion of the hydrogen and all of the oxygen react to produce a heated gas stream having a temperature within the range of from 1,100 to 1,900 C, while the boundary layer of hydrogen maintains the wall temperature at a substantially lower temperature. The heated gas stream is introduced into a hydrogenation reaction zone and provides the source of heat and hydrogen for a hydrogenation reaction. There also is provided means for quenching the products of the hydrogenation reaction. The present invention is particularly suitable for the hydrogenation of low-value solid carbonaceous materials to provide high yields of more valuable liquid and gaseous products. 2 figs.

  14. Zirconium Catalyst Follows a Low Energy Pathway for Carbon-Nitrogen Bond

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Formation | The Ames Laboratory Zirconium Catalyst Follows a Low Energy Pathway for Carbon-Nitrogen Bond Formation Chemists have synthesized a highly selective and highly efficient zirconium catalyst that makes new carbon-nitrogen bonds by adding a nitrogen-hydrogen bond to a carbon-carbon double bond. Nitrogen-containing chemicals are important as agrichemicals, pharmaceuticals, and specialty chemicals. These zirconium catalysts are expected to show greater tolerance to other functionality

  15. Zirconium Catalyst Follows a Low Energy Pathway for Carbon-Nitrogen Bond

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Formation | The Ames Laboratory Zirconium Catalyst Follows a Low Energy Pathway for Carbon-Nitrogen Bond Formation Chemists have synthesized a highly selective and highly efficient zirconium catalyst that makes new carbon-nitrogen bonds by adding a nitrogen-hydrogen bond to a carbon-carbon double bond. Nitrogen-containing chemicals are important as agrichemicals, pharmaceuticals, and specialty chemicals. These zirconium catalysts are expected to show greater tolerance to other functionality

  16. Hydrogen Storage in Carbon Nanotubes Through Formation of C-H...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Storage in Carbon Nanotubes Through Formation of C-H Bonds Print Two of the major ... One possible solution to these problems is to use an energy carrier such as hydrogen, and ...

  17. Structural origin of bulk molecular hydrogen in hydrogenated amorphous silicon

    SciTech Connect (OSTI)

    Liu, X.; Pohl, R.O.; Crandall, R.S.

    1999-07-01

    The elastic anomaly observed previously at the triple point of bulk molecular hydrogen in hydrogenated amorphous silicon films prepared by hot-wire chemical-vapor deposition has also been observed in deuterated films at the triple point of D{sub 2}. The origin of this anomaly has now been traced to bubbles formed at the crystalline-amorphous interface. An upper limit of the pressure in these bubbles at their formation temperature, 440 C, has been estimated to be 11 MPa, and is suggested to be a measure of the bonding strength between film and substrate at that temperature. Bubble formation after heat treatment at 400 C has also been observed in films prepared by plasma-enhanced chemical-vapor deposition. The internal friction anomalies resemble those observed previously in cold-worked hydrogenated iron where they have been interpreted through plastic deformation of solid hydrogen in voids.

  18. Trending: Metal Oxo Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Trending: Metal Oxo Bonds Print Metal oxides are important for scientific and technical applications in a variety of disciplines, including materials science, chemistry, and biology. Highly covalent metal-oxygen multiple bonds (metal oxos) are the building blocks of metal oxides and have a bearing on the oxide's desirable chemical, magnetic, electronic, and thermal properties. The lack of a more sophisticated grasp of bonding in metal oxides constitutes a roadblock to innovation in a wide

  19. BONDING ALUMINUM METALS

    DOE Patents [OSTI]

    Noland, R.A.; Walker, D.E.

    1961-06-13

    A process is given for bonding aluminum to aluminum. Silicon powder is applied to at least one of the two surfaces of the two elements to be bonded, the two elements are assembled and rubbed against each other at room temperature whereby any oxide film is ruptured by the silicon crystals in the interface; thereafter heat and pressure are applied whereby an aluminum-silicon alloy is formed, squeezed out from the interface together with any oxide film, and the elements are bonded.

  20. Trending: Metal Oxo Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in both in technological and biological processes that are often governed by careful control over the physical and chemical properties of metal-oxygen bonds. For example,...

  1. Trending: Metal Oxo Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and technical applications in a variety of disciplines, including materials science, chemistry, and biology. Highly covalent metal-oxygen multiple bonds (metal oxos) are the...

  2. Hydrogen Production

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Production Hydrogen can be produced using diverse, domestic resources. Fossil fuels, such as natural gas and coal, can be converted to produce hydrogen, and the use of carbon capture, utilization, and storage can reduce the carbon footprint of these processes. Hydrogen can also be produced from low carbon and renewable resources, including biomass grown from non-food crops and splitting water using electricity from wind, solar, geothermal, nuclear, and hydroelectric. This diversity of potential

  3. Hydrogen Liquefaction

    Broader source: Energy.gov (indexed) [DOE]

    Equilibrium Liquid Hydrogen is 0.2% Ortho, 99.8% Para 3 Liquid Supply North America ... Forecourt: attributes & challenges (NFPA-55) Energy & Capital: LH2 will ...

  4. New Pathways and Metrics for Enhanced, Reversible Hydrogen Storage in Boron-Doped Carbon Nanospaces

    SciTech Connect (OSTI)

    Pfeifer, Peter; Wexler, Carlos; Hawthorne, M. Frederick; Lee, Mark W.; Jalistegi, Satish S.

    2014-08-14

    This project, since its start in 2007—entitled “Networks of boron-doped carbon nanopores for low-pressure reversible hydrogen storage” (2007-10) and “New pathways and metrics for enhanced, reversible hydrogen storage in boron-doped carbon nanospaces” (2010-13)—is in support of the DOE's National Hydrogen Storage Project, as part of the DOE Hydrogen and Fuel Cells Program’s comprehensive efforts to enable the widespread commercialization of hydrogen and fuel cell technologies in diverse sectors of the economy. Hydrogen storage is widely recognized as a critical enabling technology for the successful commercialization and market acceptance of hydrogen powered vehicles. Storing sufficient hydrogen on board a wide range of vehicle platforms, at energy densities comparable to gasoline, without compromising passenger or cargo space, remains an outstanding technical challenge. Of the main three thrust areas in 2007—metal hydrides, chemical hydrogen storage, and sorption-based hydrogen storage—sorption-based storage, i.e., storage of molecular hydrogen by adsorption on high-surface-area materials (carbons, metal-organic frameworks, and other porous organic networks), has emerged as the most promising path toward achieving the 2017 DOE storage targets of 0.055 kg H2/kg system (“5.5 wt%”) and 0.040 kg H2/liter system. The objective of the project is to develop high-surface-area carbon materials that are boron-doped by incorporation of boron into the carbon lattice at the outset, i.e., during the synthesis of the material. The rationale for boron-doping is the prediction that boron atoms in carbon will raise the binding energy of hydro- gen from 4-5 kJ/mol on the undoped surface to 10-14 kJ/mol on a doped surface, and accordingly the hydro- gen storage capacity of the material. The mechanism for the increase in binding energy is electron donation from H2 to electron-deficient B atoms, in the form of sp2 boron-carbon bonds. Our team is proud to have

  5. Thermal Performance and Reliability of Bonded Interfaces | Department of

    Broader source: Energy.gov (indexed) [DOE]

    Energy 2 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting ape028_devoto_2012_o.pdf (1.45 MB) More Documents & Publications Reliability of Bonded Interfaces Thermal Performance and Reliability of Bonded Interfaces Thermal Performance and Reliability Energy

    1 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation ape028_narumanchi_2011_o.pdf (740.98 KB) More

  6. Qualified Energy Conservation Bonds

    Broader source: Energy.gov [DOE]

    A Qualified Energy Conservation Bond (QECB) is a bond that enables qualified state, tribal, and local government issuers to borrow money at attractive rates to fund energy conservation projects (it is important to note that QECBs are not grants). A QECB is among the lowest-cost public financing tools because the U.S. Department of the Treasury subsidizes the issuer's borrowing costs.

  7. Hydrogen | Open Energy Information

    Open Energy Info (EERE)

    Hydrogen Jump to: navigation, search TODO: Add description Related Links List of Companies in Hydrogen Sector List of Hydrogen Incentives Hydrogen Energy Data Book Retrieved from...

  8. Network analysis of proton transfer in liquid water

    SciTech Connect (OSTI)

    Shevchuk, Roman; Rao, Francesco; Agmon, Noam

    2014-06-28

    Proton transfer in macromolecular systems is a fascinating yet elusive process. In the last ten years, molecular simulations have shown to be a useful tool to unveil the atomistic mechanism. Notwithstanding, the large number of degrees of freedom involved make the accurate description of the process very hard even for the case of proton diffusion in bulk water. Here, multi-state empirical valence bond molecular dynamics simulations in conjunction with complex network analysis are applied to study proton transfer in liquid water. Making use of a transition network formalism, this approach takes into account the time evolution of several coordinates simultaneously. Our results provide evidence for a strong dependence of proton transfer on the length of the hydrogen bond solvating the Zundel complex, with proton transfer enhancement as shorter bonds are formed at the acceptor site. We identify six major states (nodes) on the network leading from the special pair to a more symmetric Zundel complex required for transferring the proton. Moreover, the second solvation shell specifically rearranges to promote the transfer, reiterating the idea that solvation beyond the first shell of the Zundel complex plays a crucial role in the process.

  9. Hydrogen Bibliography

    SciTech Connect (OSTI)

    Not Available

    1991-12-01

    The Hydrogen Bibliography is a compilation of research reports that are the result of research funded over the last fifteen years. In addition, other documents have been added. All cited reports are contained in the National Renewable Energy Laboratory (NREL) Hydrogen Program Library.

  10. Insights from Hydrogen Refueling Station Manufacturing Competitiveness Analysis

    Broader source: Energy.gov [DOE]

    NREL is collaborating with Great Lakes Wind Network on comprehensive hydrogen refueling stations manufacturing competitiveness and supply chain analyses. This presentation to the 2015 Fuel Cell...

  11. Florida Hydrogen Initiative

    SciTech Connect (OSTI)

    Block, David L

    2013-06-30

    The Florida Hydrogen Initiative (FHI) was a research, development and demonstration hydrogen and fuel cell program. The FHI program objectives were to develop Florida?s hydrogen and fuel cell infrastructure and to assist DOE in its hydrogen and fuel cell activities The FHI program funded 12 RD&D projects as follows: Hydrogen Refueling Infrastructure and Rental Car Strategies -- L. Lines, Rollins College This project analyzes strategies for Florida's early stage adaptation of hydrogen-powered public transportation. In particular, the report investigates urban and statewide network of refueling stations and the feasibility of establishing a hydrogen rental-car fleet based in Orlando. Methanol Fuel Cell Vehicle Charging Station at Florida Atlantic University ? M. Fuchs, EnerFuel, Inc. The project objectives were to design, and demonstrate a 10 kWnet proton exchange membrane fuel cell stationary power plant operating on methanol, to achieve an electrical energy efficiency of 32% and to demonstrate transient response time of less than 3 milliseconds. Assessment of Public Understanding of the Hydrogen Economy Through Science Center Exhibits, J. Newman, Orlando Science Center The project objective was to design and build an interactive Science Center exhibit called: ?H2Now: the Great Hydrogen Xchange?. On-site Reformation of Diesel Fuel for Hydrogen Fueling Station Applications ? A. Raissi, Florida Solar Energy Center This project developed an on-demand forecourt hydrogen production technology by catalytically converting high-sulfur hydrocarbon fuels to an essentially sulfur-free gas. The removal of sulfur from reformate is critical since most catalysts used for the steam reformation have limited sulfur tolerance. Chemochromic Hydrogen Leak Detectors for Safety Monitoring ? N. Mohajeri and N. Muradov, Florida Solar Energy Center This project developed and demonstrated a cost-effective and highly selective chemochromic (visual) hydrogen leak detector for safety monitoring

  12. Qualified Energy Conservation Bonds

    Broader source: Energy.gov [DOE]

    Provides an in-depth description of qualified energy conservation bonds, including process and mechanics, case studies, utilization trends, barriers, and regulatory and legal issues. Author: Energy Programs Consortium

  13. Bonding aerogels with polyurethanes

    SciTech Connect (OSTI)

    Matthews, F.M.; Hoffman, D.M.

    1989-11-01

    Aerogels, porous silica glasses with ultra-fine cell size (30nm), are made by a solution gelation (sol-gel) process. The resulting gel is critical point dried to densities from 0.15--0.60 g/cc. This material is machinable, homogeneous, transparent, coatable and bondable. To bond aerogel an adhesive should have long cure time, no attack on the aerogel structure, and high strength. Several epoxies and urethanes were examined to determine if they satisfied these conditions. Bond strengths above 13 psi were found with double bubble and DP-110 epoxies and XI-208/ODA-1000 and Castall U-2630 urethanes. Hardman Kalex Tough Stuff'' A-85 hardness urethane gave 18 psi bond strength. Hardman A-85, Tuff-Stuff'' was selected for further evaluation because it produced bond strengths comparable to the adherend cohesive strength. 5 refs., 2 figs.

  14. Breaking the Bond

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Breaking the Bond 1663 Los Alamos science and technology magazine Latest Issue:July 2016 past issues All Issues » submit Breaking the Bond Can chemistry help unbind us from fossil fuels? July 21, 2016 info graphic gas pump Accelerating toward a more sustainable future: gas pumps may someday soon contain bio-gasoline made from plants. We are condensing millions of years of fossilization into a few chemical reactions. Fossil fuels are a finite resource. Unfortunately, the existing global

  15. Low temperature material bonding technique

    DOE Patents [OSTI]

    Ramsey, J. Michael (Knoxville, TN); Foote, Robert S. (Oak Ridge, TN)

    2002-02-12

    A method of performing a lower temperature bonding technique to bond together two mating pieces of glass includes applying a sodium silicate aqueous solution between the two pieces.

  16. Low Temperature Material Bonding Technique

    DOE Patents [OSTI]

    Ramsey, J. Michael (Knoxville, TN); Foote, Robert S. (Oak Ridge, TN)

    2000-10-10

    A method of performing a lower temperature bonding technique to bond together two mating pieces of glass includes applying a sodium silicate aqueous solution between the two pieces.

  17. Hydrogen Production

    Fuel Cell Technologies Publication and Product Library (EERE)

    This 2-page fact sheet provides a brief introduction to hydrogen production technologies. Intended for a non-technical audience, it explains how different resources and processes can be used to produ

  18. Renewable Hydrogen

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrogen NREL Hydrogen Technologies and Systems Center Dr. Robert J. Remick November 16, 2009 NREL/PR-560-47433 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. U.S. Dependence on Imported Oil National Renewable Energy Laboratory Innovation for Our Energy Future 2 Energy Solutions are Challenging We need a balanced portfolio of options- including clean, domestic energy

  19. Hydrogen local vibrational modes in semiconductors

    SciTech Connect (OSTI)

    McCluskey, M D

    1997-06-01

    Following, a review of experimental techniques, theory, and previous work, the results of local vibrational mode (LVM) spectroscopy on hydrogen-related complexes in several different semiconductors are discussed. Hydrogen is introduced either by annealing in a hydrogen ambient. exposure to a hydrogen plasma, or during growth. The hydrogen passivates donors and acceptors in semiconductors, forming neutral complexes. When deuterium is substituted for hydrogen. the frequency of the LVM decreases by approximately the square root of two. By varying the temperature and pressure of the samples, the microscopic structures of hydrogen-related complexes are determined. For group II acceptor-hydrogen complexes in GaAs, InP, and GaP, hydrogen binds to the host anion in a bond-centered orientation, along the [111] direction, adjacent to the acceptor. The temperature dependent shift of the LVMs are proportional to the lattice thermal energy U(T), a consequence of anharmonic coupling between the LVM and acoustical phonons. In the wide band gap semiconductor ZnSe, epilayers grown by metalorganic chemical vapor phase epitaxy (MOCVD) and doped with As form As-H complexes. The hydrogen assumes a bond-centered orientation, adjacent to a host Zn. In AlSb, the DX centers Se and Te are passivated by hydrogen. The second, third, and fourth harmonics of the wag modes are observed. Although the Se-D complex has only one stretch mode, the Se-H stretch mode splits into three peaks. The anomalous splitting is explained by a new interaction between the stretch LVM and multi-phonon modes of the lattice. As the temperature or pressure is varied, and anti-crossing is observed between LVM and phonon modes.

  20. Storing Hydrogen

    SciTech Connect (OSTI)

    Kim, Hyun Jeong; Karkamkar, Abhijeet J.; Autrey, Thomas; Chupas, Peter; Proffen, Thomas E.

    2010-05-31

    Researchers have been studying mesoporous materials for almost two decades with a view to using them as hosts for small molecules and scaffolds for molding organic compounds into new hybrid materials and nanoparticles. Their use as potential storage systems for large quantities of hydrogen has also been mooted. Such systems that might hold large quantities of hydrogen safely and in a very compact volume would have enormous potential for powering fuel cell vehicles, for instance. A sponge-like form of silicon dioxide, the stuff of sand particles and computer chips, can soak up and store other compounds including hydrogen. Studies carried out at the XOR/BESSRC 11-ID-B beamline at the APS have revealed that the nanoscopic properties of the hydrogenrich compound ammonia borane help it store hydrogen more efficiently than usual. The material may have potential for addressing the storage issues associated with a future hydrogen economy. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  1. Hydrogen program overview

    SciTech Connect (OSTI)

    Gronich, S.

    1997-12-31

    This paper consists of viewgraphs which summarize the following: Hydrogen program structure; Goals for hydrogen production research; Goals for hydrogen storage and utilization research; Technology validation; DOE technology validation activities supporting hydrogen pathways; Near-term opportunities for hydrogen; Market for hydrogen; and List of solicitation awards. It is concluded that a full transition toward a hydrogen economy can begin in the next decade.

  2. Detection of Hydrogen Spillover in Palladium-Modified Activated Carbon Fibers During Hydrogen Adsorption

    SciTech Connect (OSTI)

    Contescu, Cristian I; Brown, Craig; Liu, Yun; Bhat, Vinay V; Gallego, Nidia C

    2009-01-01

    Palladium-modified activated carbon fibers (Pd-ACF) are being evaluated for adsorptive hydrogen storage at near-ambient conditions because of their enhanced hydrogen uptake in comparison to Pd-free activated carbon fibers (ACF). The net uptake enhancement (at room temperature and 20 bar) is in excess of the amount corresponding to formation of Pd hydride, and is usually attributed to hydrogen spillover. In this paper, inelastic neutron scattering was used to demonstrate the formation of new C-H bonds in Pd-containing activated carbon fibers after exposure to hydrogen at 20 oC and 1.6 MPa, at the expense of physisorbed H2. This finding is a post-factum proof of the atomic nature of H species formed in presence of a Pd catalyst, and of their subsequent spillover and binding to the carbon support. Chemisorption of hydrogen may explain the reduction in hydrogen uptake from first to second adsorption cycle.

  3. Hydrogen Technologies Group

    SciTech Connect (OSTI)

    Not Available

    2008-03-01

    The Hydrogen Technologies Group at the National Renewable Energy Laboratory advances the Hydrogen Technologies and Systems Center's mission by researching a variety of hydrogen technologies.

  4. Hydrogen | Open Energy Information

    Open Energy Info (EERE)

    Hydrogen Jump to: navigation, search <-- Back to Hydrogen Gateway Technical Reference for Hydrogen Compatibility of Materials KIA FCEV SUNRISE MG 7955 6 7.jpg Guidance on materials...

  5. Hydrogen Transition Infrastructure Analysis

    SciTech Connect (OSTI)

    Melendez, M.; Milbrandt, A.

    2005-05-01

    Presentation for the 2005 U.S. Department of Energy Hydrogen Program review analyzes the hydrogen infrastructure needed to accommodate a transitional hydrogen fuel cell vehicle demand.

  6. NMR study of ortho-molecular hydrogen in hydrogenated amorphous silicon

    SciTech Connect (OSTI)

    Su, T.; Taylor, P.C.; Chen, S.; Crandall, R.S.; Mahan, A.H.

    1999-07-01

    A Jeener-Broekaert three-pulse sequence is used to investigate ortho-molecular hydrogen (o-H{sub 2}) in device quality amorphous silicon films prepared by plasma enhanced chemical vapor deposition (PECVD) and hot wire CVD (HWCVD). For the PECVD sample, the concentration of hydrogen moleculars is {approximately}11% of the total hydrogen concentration, one order of magnitude larger than that inferred from spin-lattice relaxation time measurements ({approximately}1%). Hence, most of the hydrogen molecules do not serve as effective relaxation centers. For HWCVD samples with {approximately}3 to 4% hydrogen and very low void densities, the concentrations of hydrogen molecules are {approximately}1% of the total hydrogen concentration. In these samples, spin-lattice relaxation measurements for bonded hydrogen indicate that the concentration of hydrogen molecules that contribute to spin-lattice relaxation is at most 0.1% of the total hydrogen concentration. Spin-lattice relaxation time (T{sub 1}) measurements of ortho-molecular hydrogen indicate two very different T{sub 1}'s. The longer T{sub 1} is {approximately} 0.6 s, possibly due to an electric quadrupole-quadrupole (EQQ) interaction between o-H{sub 2} molecules and, the shorter T{sub 1} is {approximately} 3 ms, very close to that calculated for a two-phonon Raman process for rotating o-H{sub 2}.

  7. Diffusion Bonding Characterization

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Diffusion Bonding Characterization - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs

  8. GRAPHITE BONDING METHOD

    DOE Patents [OSTI]

    King, L.D.P.

    1964-02-25

    A process for bonding or joining graphite members together in which a thin platinum foil is placed between the members, heated in an inert atmosphere to a temperature of 1800 deg C, and then cooled to room temperature is described. (AEC)

  9. Photochemical tissue bonding

    DOE Patents [OSTI]

    Redmond, Robert W.; Kochevar, Irene E.

    2012-01-10

    Photochemical tissue bonding methods include the application of a photosensitizer to a tissue and/or tissue graft, followed by irradiation with electromagnetic energy to produce a tissue seal. The methods are useful for tissue adhesion, such as in wound closure, tissue grafting, skin grafting, musculoskeletal tissue repair, ligament or tendon repair and corneal repair.

  10. Chemically bonded phospho-silicate ceramics

    DOE Patents [OSTI]

    Wagh, Arun S.; Jeong, Seung Y.; Lohan, Dirk; Elizabeth, Anne

    2003-01-01

    A chemically bonded phospho-silicate ceramic formed by chemically reacting a monovalent alkali metal phosphate (or ammonium hydrogen phosphate) and a sparsely soluble oxide, with a sparsely soluble silicate in an aqueous solution. The monovalent alkali metal phosphate (or ammonium hydrogen phosphate) and sparsely soluble oxide are both in powder form and combined in a stochiometric molar ratio range of (0.5-1.5):1 to form a binder powder. Similarly, the sparsely soluble silicate is also in powder form and mixed with the binder powder to form a mixture. Water is added to the mixture to form a slurry. The water comprises 50% by weight of the powder mixture in said slurry. The slurry is allowed to harden. The resulting chemically bonded phospho-silicate ceramic exhibits high flexural strength, high compression strength, low porosity and permeability to water, has a definable and bio-compatible chemical composition, and is readily and easily colored to almost any desired shade or hue.

  11. Communicating Hydrogen: Matching Message with Media | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Communicating Hydrogen: Matching Message with Media Communicating Hydrogen: Matching Message with Media This presentation by DOE's Christy Cooper was given at the State/Regional Hydrogen and Fuel Cell Initiatives Networking Meeting in March 2007. h2_communications_media.pdf (250.63 KB) More Documents & Publications Documnet for Hydrogen State and Regional Workshop, March 30, 2008, Sacramento, CA Public Relations for Energy Sustainability Microsoft Word - What's New in IE8 v3

  12. Hydrogen Technology Validation

    SciTech Connect (OSTI)

    2008-11-01

    This fact sheet provides a basic introduction to the DOE Hydrogen National Hydrogen Learning Demonstration for non-technical audiences.

  13. Hydrogen Technology Validation

    Fuel Cell Technologies Publication and Product Library (EERE)

    This fact sheet provides a basic introduction to the DOE Hydrogen National Hydrogen Learning Demonstration for non-technical audiences.

  14. Neutron Compton Scattering as a Probe of Hydrogen Bonded (and...

    Office of Scientific and Technical Information (OSTI)

    ... We hope to carry them out under the renewal proposal. A third theme was to confront the ... Country of Publication: United States Language: English Subject: 75 CONDENSED MATTER ...

  15. A Surprising Path for Proton Transfer Without Hydrogen Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ... of the wave-function along the proton transfer pathway. Right: A two-dimensional potential-energy-surface scan shows the proton transfer path in the dimer ion involving a ...

  16. Neutron Compton Scattering as a Probe of Hydrogen Bonded (and...

    Office of Scientific and Technical Information (OSTI)

    States) Oak Ridge Gaseous Diffusion Plant (K-25), Oak Ridge, TN (United States) Oak ... Ridge, TN (United States) Oak Ridge Y-12 Plant (Y-12), Oak Ridge, TN (United States) ...

  17. Neutron Compton Scattering as a Probe of Hydrogen Bonded (and...

    Office of Scientific and Technical Information (OSTI)

    ... Close Cite: Bibtex Format Close 0 pages in this document matching the terms "" Search For Terms: Enter terms in the toolbar above to search the full text of this document for ...

  18. Hydrogen-bond Specific Materials Modification in Group IV Semiconducto...

    Office of Scientific and Technical Information (OSTI)

    defects such as interfaces and dopant layers, as well as other important semiconducting systems. Even so, the emphasis remains on phenomena and processes far from equilibrium,...

  19. Bond Program | Open Energy Information

    Open Energy Info (EERE)

    Bond Program Jump to: navigation, search This article is a stub. You can help OpenEI by expanding it. Retrieved from "http:en.openei.orgwindex.php?titleBondProgram&oldid5427...

  20. Low temperature reactive bonding

    DOE Patents [OSTI]

    Makowiecki, Daniel M. (Livermore, CA); Bionta, Richard M. (Livermore, CA)

    1995-01-01

    The joining technique requires no external heat source and generates very little heat during joining. It involves the reaction of thin multilayered films deposited on faying surfaces to create a stable compound that functions as an intermediate or braze material in order to create a high strength bond. While high temperatures are reached in the reaction of the multilayer film, very little heat is generated because the films are very thin. It is essentially a room temperature joining process.

  1. Opportunities in Bond Financing

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Opportunities in Bond Financing James Dack Vice President Alternative Energy Finance Group Stern Brothers & Co. Seattle, WA 98101 Biogas and Fuel Cells Workshop National Renewable Energy Laboratory Golden, Colorado June 11-13, 2012 2 INTRODUCTION * Stern Brothers, founded in 1917 and headquartered in St. Louis, is an investment banking firm that is focused on project financing (taxable and tax-exempt) for renewable energy, real estate, higher education and healthcare. * Stern's Alternative

  2. Network Maps

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Network Maps Engineering Services The Network Network Maps Network Traffic Volume Historical Network Maps Network Facts & Stats Connected Sites Peering Connections ESnet...

  3. IMPROVED BONDING METHOD

    DOE Patents [OSTI]

    Padgett, E.V. Jr.; Warf, D.H.

    1964-04-28

    An improved process of bonding aluminum to aluminum without fusion by ultrasonic vibrations plus pressure is described. The surfaces to be bonded are coated with an aqueous solution of alkali metal stearate prior to assembling for bonding. (AEC) O H19504 Present information is reviewed on steady state proliferation, differentiation, and maturation of blood cells in mammals. Data are cited from metabolic tracer studies, autoradiographic studies, cytologic studies, studies of hematopoietic response to radiation injuries, and computer analyses of blood cell production. A 3-step model for erythropoiesis and a model for granulocyte kinetics are presented. New approaches to the study of lymphocytopoiesis described include extracorporeal blood irradiation to deplete lymphocytic tissue without direct injury to the formative tissues as a means to study the stressed system, function control, and rates of proliferation. It is pointed out that present knowledge indicates that lymphocytes comprise a mixed family, with diverse life spans, functions, and migration patterns with apparent aimless recycling from modes to lymph to blood to nodes that has not yet been quantitated. Areas of future research are postulated. (70 references.) (C.H.)

  4. Bonding Tools | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Bonding Tools Bonding Tools Bonds are one of the most common forms of financing used by state and local governments, because they are a low-cost source of capital available to most entities. State and local officials may consider using bonds for a variety of clean energy purposes, including: Financing a specific set of energy upgrades in their own facilities (can be combined with an energy savings performance contract) Capitalizing finance programs (e.g., revolving loan fund) for public sector

  5. Qualified Energy Conservation Bond Webinars

    Broader source: Energy.gov [DOE]

    Provides a listing of past qualified energy conservation bond webinars and associated files. Author: U.S. Department of Energy

  6. Hydrogen Sensor Testing, Hydrogen Technologies (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2008-11-01

    Factsheet describing the hydrogen sensor testing laboratory at the National Renewable Energy Laboratory.

  7. Chemical Hydrogen Storage Materials

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Troy A. Semelsberger Los Alamos National Laboratory Hydrogen Storage Summit Jan 27-29, 2015 Denver, CO Chemical Hydrogen Storage Materials 2 Objectives 1. Assess chemical hydrogen storage materials that can exceed 700 bar compressed hydrogen tanks 2. Status (state-of-the-art) of chemical hydrogen storage materials 3. Identify key material characteristics 4. Identify obstacles, challenges and risks for the successful deployment of chemical hydrogen materials in a practical on-board hydrogen

  8. The Hydriding Kinetics of Organic Hydrogen Getters

    SciTech Connect (OSTI)

    Powell, G. L.

    2002-02-11

    The aging of hermetically sealed systems is often accompanied by the gradual production of hydrogen gas that is a result of the decay of environmental gases and the degradation of organic materials. In particular, the oxygen, water, hydrogen ''equilibrium'' is affected by the removal of oxygen due the oxidation of metals and organic materials. This shift of the above ''equilibrium'' towards the formation of hydrogen gas, particularly in crevices, may eventually reach an explosive level of hydrogen gas or degrade metals by hydriding them. The latter process is generally delayed until the oxidizing species are significantly reduced. Organic hydrogen getters introduced by Allied Signal Aerospace Company, Kansas City Division have proven to be a very effective means of preventing hydrogen gas accumulation in sealed containers. These getters are relatively unaffected by air and environmental gases. They can be packaged in a variety of ways to fit particular needs such as porous pellets, fine or coarse [gravel] powder, or loaded into silicone rubber. The hydrogen gettering reactions are extremely irreversible since the hydrogen gas is converted into an organic hydrocarbon. These getters are based on the palladium-catalyzed hydrogenation of triple bonds to double and then single bonds in aromatic aryl compounds. DEB (1,4 bis (phenyl ethynyl) benzene) typically mixed with 25% by weight carbon with palladium (1% by weight of carbon) is one of the newest and best of these organic hydrogen getters. The reaction mechanisms are complex involving solid state reaction with a heterogeneous catalyst leading to the many intermediates, including mixed alkyl and aryl hydrocarbons with the possibilities of many isomers. The reaction kinetics mechanisms are also strongly influenced by the form in which they are packaged. For example, the hydriding rates for pellets and gravel have a strong dependence on reaction extent (i.e., DEB reduction) and a kinetic order in pressure of 0

  9. Hydrogen detector

    DOE Patents [OSTI]

    Kanegae, Naomichi; Ikemoto, Ichiro

    1980-01-01

    A hydrogen detector of the type in which the interior of the detector is partitioned by a metal membrane into a fluid section and a vacuum section. Two units of the metal membrane are provided and vacuum pipes are provided independently in connection to the respective units of the metal membrane. One of the vacuum pipes is connected to a vacuum gauge for static equilibrium operation while the other vacuum pipe is connected to an ion pump or a set of an ion pump and a vacuum gauge both designed for dynamic equilibrium operation.

  10. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

    DOE Patents [OSTI]

    Lilga, M.A.; Hallen, R.T.

    1991-10-15

    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately [pi]-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancillary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H[sub 2] from mixed gas streams such as the product gas from coal gasification processes. 3 figures.

  11. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

    DOE Patents [OSTI]

    Lilga, Michael A.; Hallen, Richard T.

    1991-01-01

    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately .pi.-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancilliary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H.sub.2 from mixed gas streams such as the product gas from coal gasification processes.

  12. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

    DOE Patents [OSTI]

    Lilga, M.A.; Hallen, R.T.

    1990-08-28

    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately [pi]-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancillary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H[sub 2] from mixed gas streams such as the producer gas from coal gasification processes. 3 figs.

  13. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

    DOE Patents [OSTI]

    Lilga, Michael A.; Hallen, Richard T.

    1990-01-01

    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately .pi.-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancilliary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H.sub.2 from mixed gas streams such as the produce gas from coal gasification processes.

  14. Low temperature reactive bonding

    DOE Patents [OSTI]

    Makowiecki, D.M.; Bionta, R.M.

    1995-01-17

    The joining technique is disclosed that requires no external heat source and generates very little heat during joining. It involves the reaction of thin multilayered films deposited on faying surfaces to create a stable compound that functions as an intermediate or braze material in order to create a high strength bond. While high temperatures are reached in the reaction of the multilayer film, very little heat is generated because the films are very thin. It is essentially a room temperature joining process. 5 figures.

  15. DOE Hydrogen and Fuel Cells Program Record 11007: Hydrogen Threshold...

    Office of Environmental Management (EM)

    1007: Hydrogen Threshold Cost Calculation DOE Hydrogen and Fuel Cells Program Record 11007: Hydrogen Threshold Cost Calculation The hydrogen threshold cost is defined as the ...

  16. Safety and Regulatory Structure for CNG, CNG-Hydrogen, Hydrogen...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrogen, Hydrogen Vehicles and Fuels in China Safety and Regulatory Structure for CNG, CNG-Hydrogen, Hydrogen Vehicles and Fuels in China Presentation given by Jinyang Zheng of ...

  17. Ovonic Hydrogen Systems LLC formerly Texaco Ovonic Hydrogen Systems...

    Open Energy Info (EERE)

    Hydrogen Systems LLC formerly Texaco Ovonic Hydrogen Systems LLC Jump to: navigation, search Name: Ovonic Hydrogen Systems LLC (formerly Texaco Ovonic Hydrogen Systems LLC) Place:...

  18. Final Report: Metal Perhydrides for Hydrogen Storage

    SciTech Connect (OSTI)

    Hwang, J-Y.; Shi, S.; Hackney, S.; Swenson, D.; Hu, Y.

    2011-07-26

    Hydrogen is a promising energy source for the future economy due to its environmental friendliness. One of the important obstacles for the utilization of hydrogen as a fuel source for applications such as fuel cells is the storage of hydrogen. In the infrastructure of the expected hydrogen economy, hydrogen storage is one of the key enabling technologies. Although hydrogen possesses the highest gravimetric energy content (142 KJ/g) of all fuels, its volumetric energy density (8 MJ/L) is very low. It is desired to increase the volumetric energy density of hydrogen in a system to satisfy various applications. Research on hydrogen storage has been pursed for many years. Various storage technologies, including liquefaction, compression, metal hydride, chemical hydride, and adsorption, have been examined. Liquefaction and high pressure compression are not desired due to concerns related to complicated devices, high energy cost and safety. Metal hydrides and chemical hydrides have high gravimetric and volumetric energy densities but encounter issues because high temperature is required for the release of hydrogen, due to the strong bonding of hydrogen in the compounds. Reversibility of hydrogen loading and unloading is another concern. Adsorption of hydrogen on high surface area sorbents such as activated carbon and organic metal frameworks does not have the reversibility problem. But on the other hand, the weak force (primarily the van der Waals force) between hydrogen and the sorbent yields a very small amount of adsorption capacity at ambient temperature. Significant storage capacity can only be achieved at low temperatures such as 77K. The use of liquid nitrogen in a hydrogen storage system is not practical. Perhydrides are proposed as novel hydrogen storage materials that may overcome barriers slowing advances to a hydrogen fuel economy. In conventional hydrides, e.g. metal hydrides, the number of hydrogen atoms equals the total valence of the metal ions. One Li

  19. Process for manufacture of thick film hydrogen sensors

    DOE Patents [OSTI]

    Perdieu, Louisa H.

    2000-09-09

    A thick film process for producing hydrogen sensors capable of sensing down to a one percent concentration of hydrogen in carrier gasses such as argon, nitrogen, and air. The sensor is also suitable to detect hydrogen gas while immersed in transformer oil. The sensor includes a palladium resistance network thick film printed on a substrate, a portion of which network is coated with a protective hydrogen barrier. The process utilizes a sequence of printing of the requisite materials on a non-conductive substrate with firing temperatures at each step which are less than or equal to the temperature at the previous step.

  20. Mechanochemical hydrogenation of coal

    DOE Patents [OSTI]

    Yang, Ralph T.; Smol, Robert; Farber, Gerald; Naphtali, Leonard M.

    1981-01-01

    Hydrogenation of coal is improved through the use of a mechanical force to reduce the size of the particulate coal simultaneously with the introduction of gaseous hydrogen, or other hydrogen donor composition. Such hydrogen in the presence of elemental tin during this one-step size reduction-hydrogenation further improves the yield of the liquid hydrocarbon product.

  1. CTP Hydrogen | Open Energy Information

    Open Energy Info (EERE)

    CTP Hydrogen Jump to: navigation, search Name: CTP Hydrogen Place: Westborough, Massachusetts Zip: 1581 Sector: Hydro, Hydrogen Product: CTP Hydrogen is an early stage company...

  2. Solder extrusion pressure bonding process and bonded products produced thereby

    DOE Patents [OSTI]

    Beavis, L.C.; Karnowsky, M.M.; Yost, F.G.

    1992-06-16

    Disclosed is a process for production of soldered joints which are highly reliable and capable of surviving 10,000 thermal cycles between about [minus]40 C and 110 C. Process involves interposing a thin layer of a metal solder composition between the metal surfaces of members to be bonded and applying heat and up to about 1000 psi compression pressure to the superposed members, in the presence of a reducing atmosphere, to extrude the major amount of the solder composition, contaminants including fluxing gases and air, from between the members being bonded, to form a very thin, strong intermetallic bonding layer having a thermal expansion tolerant with that of the bonded members.

  3. Solder extrusion pressure bonding process and bonded products produced thereby

    DOE Patents [OSTI]

    Beavis, Leonard C.; Karnowsky, Maurice M.; Yost, Frederick G.

    1992-01-01

    Production of soldered joints which are highly reliable and capable of surviving 10,000 thermal cycles between about -40.degree. C. and 110.degree. C. Process involves interposing a thin layer of a metal solder composition between the metal surfaces of members to be bonded and applying heat and up to about 1000 psi compression pressure to the superposed members, in the presence of a reducing atmosphere, to extrude the major amount of the solder composition, contaminants including fluxing gases and air, from between the members being bonded, to form a very thin, strong intermetallic bonding layer having a thermal expansion tolerant with that of the bonded members.

  4. Characterization of hydrogenated amorphous germanium compounds obtained by x-ray chemical vapor deposition of germane: Effect of the irradiation dose on optical parameters and structural order

    SciTech Connect (OSTI)

    Arrais, Aldo; Benzi, Paola; Bottizzo, Elena; Demaria, Chiara

    2007-11-15

    Hydrogenated nonstoichiometric germanium materials have been produced by x-ray activated-chemical vapor deposition from germane. The reactions pattern leading to the solid products has been investigated. The dose effect on the composition, the local bonding configuration, and structural characteristics of the deposited solids has been studied using infrared absorption and Raman spectroscopy and has been discussed. Optical parameters have been also determined from ultraviolet-visible spectrophotometry data. The results show that the solids are formed by a random bound network of germanium and hydrogen atoms with a-Ge zones dispersed in the matrix. The Raman results and optical parameters indicate that the structural order, both short-range and intermediate-range, decreases with increasing irradiation time. This behavior suggests that the solid is involved in the reactions leading to the final product and indicates that the formation of amorphous germanium zones is stimulated by postdeposition irradiation, which induces compositional and structural modifications.

  5. Bond-valence methods for pKa prediction. II. Bond-valence, electrostatic, molecular geometry, and solvation effects

    SciTech Connect (OSTI)

    Bickmore, Barry R.; Rosso, Kevin M.; Tadanier, Christopher J.; Bylaska, Eric J.; Doud, Darrin

    2006-08-15

    In a previous contribution, we outlined a method for predicting (hydr)oxy-acid and oxide surface acidity constants based on three main factors: bond valence, Me?O bond ionicity, and molecular shape. Here electrostatics calculations and ab initio molecular dynamics simulations are used to qualitatively show that Me?O bond ionicity controls the extent to which the electrostatic work of proton removal departs from ideality, bond valence controls the extent of solvation of individual functional groups, and bond valence and molecular shape controls local dielectric response. These results are consistent with our model of acidity, but completely at odds with other methods of predicting acidity constants for use in multisite complexation models. In particular, our ab initio molecular dynamics simulations of solvated monomers clearly indicate that hydrogen bonding between (hydr)oxo-groups and water molecules adjusts to obey the valence sum rule, rather than maintaining a fixed valence based on the coordination of the oxygen atom as predicted by the standard MUSIC model.

  6. Vacuum fusion bonding of glass plates

    DOE Patents [OSTI]

    Swierkowski, Steve P.; Davidson, James C.; Balch, Joseph W.

    2001-01-01

    An improved apparatus and method for vacuum fusion bonding of large, patterned glass plates. One or both glass plates are patterned with etched features such as microstructure capillaries and a vacuum pumpout moat, with one plate having at least one hole therethrough for communication with a vacuum pumpout fixture. High accuracy alignment of the plates is accomplished by a temporary clamping fixture until the start of the fusion bonding heat cycle. A complete, void-free fusion bond of seamless, full-strength quality is obtained through the plates; because the glass is heated well into its softening point and because of a large, distributed force that is developed that presses the two plates together from the difference in pressure between the furnace ambient (high pressure) and the channeling and microstructures in the plates (low pressure) due to the vacuum drawn. The apparatus and method may be used to fabricate microcapillary arrays for chemical electrophoresis; for example, any apparatus using a network of microfluidic channels embedded between plates of glass or similar moderate melting point substrates with a gradual softening point curve, or for assembly of glass-based substrates onto larger substrates, such as in flat panel display systems.

  7. Vacuum fusion bonding of glass plates

    DOE Patents [OSTI]

    Swierkowski, Steve P.; Davidson, James C.; Balch, Joseph W.

    2000-01-01

    An improved apparatus and method for vacuum fusion bonding of large, patterned glass plates. One or both glass plates are patterned with etched features such as microstructure capillaries and a vacuum pumpout moat, with one plate having at least one hole therethrough for communication with a vacuum pumpout fixture. High accuracy alignment of the plates is accomplished by a temporary clamping fixture until the start of the fusion bonding heat cycle. A complete, void-free fusion bond of seamless, full-strength quality is obtained through the plates; because the glass is heated well into its softening point and because of a large, distributed force that is developed that presses the two plates together from the difference in pressure between the furnace ambient (high pressure) and the channeling and microstructures in the plates (low pressure) due to the vacuum drawn. The apparatus and method may be used to fabricate microcapillary arrays for chemical electrophoresis; for example, any apparatus using a network of microfluidic channels embedded between plates of glass or similar moderate melting point substrates with a gradual softening point curve, or for assembly of glass-based substrates onto larger substrates, such as in flat panel display systems.

  8. NREL: Learning - Hydrogen Basics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen Basics Hydrogen is a clean-burning fuel, and when combined with oxygen in a fuel cell, it produces heat and electricity with only water vapor as a by-product. But hydrogen...

  9. Evalutation of Natural Gas Pipeline Materials and Infrastructure for Hydrogen/Mixed Gas Service

    Office of Energy Efficiency and Renewable Energy (EERE)

    Objectives: To assist DOE-EE in evaluating the feasibility of using the existing natural gas transmission and distribution piping network for hydrogen/mixed gas delivery

  10. Why Hydrogen? Hydrogen from Diverse Domestic Resources

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    from Diverse Domestic Resources Hydrogen from Diverse Domestic Resources Distributed Generation Transportation HIGH EFFICIENCY HIGH EFFICIENCY & RELIABILITY & RELIABILITY ZERONEAR...

  11. Hydrogen Safety Panel

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    or otherwise restricted information. Project ID: scs07weiner PNNL-SA-65397 2 IEA HIA Task 19 Working Group Hydrogen Safety Training Props Hydrogen Safety Panel Incident...

  12. Hydrogen | Open Energy Information

    Open Energy Info (EERE)

    Hydrogen Jump to: navigation, search Hydrogen Companies Loading map... "format":"googlemaps3","type":"SATELLITE","types":"ROADMAP","SATELLITE","HYBRID","TERRAIN","limit":1000,"o...

  13. Significant Quantum Effects in Hydrogen Activation

    SciTech Connect (OSTI)

    Kyriakou, Georgios; Davidson, Erlend R.; Peng, Guowen; Roling, Luke T.; Singh, Suyash; Boucher, Matthew B.; Marcinkowski, Matthew D.; Mavrikakis, Manos; Michaelides, Angelos; Sykes, E. Charles H.

    2014-05-27

    Dissociation of molecular hydrogen is an important step in a wide variety of chemical, biological, and physical processes. Due to the light mass of hydrogen, it is recognized that quantum effects are often important to its reactivity. However, understanding how quantum effects impact the reactivity of hydrogen is still in its infancy. Here, we examine this issue using a well-defined Pd/Cu(111) alloy that allows the activation of hydrogen and deuterium molecules to be examined at individual Pd atom surface sites over a wide range of temperatures. Experiments comparing the uptake of hydrogen and deuterium as a function of temperature reveal completely different behavior of the two species. The rate of hydrogen activation increases at lower sample temperature, whereas deuterium activation slows as the temperature is lowered. Density functional theory simulations in which quantum nuclear effects are accounted for reveal that tunneling through the dissociation barrier is prevalent for H2 up to 190 K and for D2 up to 140 K. Kinetic Monte Carlo simulations indicate that the effective barrier to H2 dissociation is so low that hydrogen uptake on the surface is limited merely by thermodynamics, whereas the D2 dissociation process is controlled by kinetics. These data illustrate the complexity and inherent quantum nature of this ubiquitous and seemingly simple chemical process. Examining these effects in other systems with a similar range of approaches may uncover temperature regimes where quantum effects can be harnessed, yielding greater control of bond-breaking processes at surfaces and uncovering useful chemistries such as selective bond activation or isotope separation.

  14. Overview of interstate hydrogen pipeline systems.

    SciTech Connect (OSTI)

    Gillette, J .L.; Kolpa, R. L

    2008-02-01

    The use of hydrogen in the energy sector of the United States is projected to increase significantly in the future. Current uses are predominantly in the petroleum refining sector, with hydrogen also being used in the manufacture of chemicals and other specialized products. Growth in hydrogen consumption is likely to appear in the refining sector, where greater quantities of hydrogen will be required as the quality of the raw crude decreases, and in the mining and processing of tar sands and other energy resources that are not currently used at a significant level. Furthermore, the use of hydrogen as a transportation fuel has been proposed both by automobile manufacturers and the federal government. Assuming that the use of hydrogen will significantly increase in the future, there would be a corresponding need to transport this material. A variety of production technologies are available for making hydrogen, and there are equally varied raw materials. Potential raw materials include natural gas, coal, nuclear fuel, and renewables such as solar, wind, or wave energy. As these raw materials are not uniformly distributed throughout the United States, it would be necessary to transport either the raw materials or the hydrogen long distances to the appropriate markets. While hydrogen may be transported in a number of possible forms, pipelines currently appear to be the most economical means of moving it in large quantities over great distances. One means of controlling hydrogen pipeline costs is to use common rights-of-way (ROWs) whenever feasible. For that reason, information on hydrogen pipelines is the focus of this document. Many of the features of hydrogen pipelines are similar to those of natural gas pipelines. Furthermore, as hydrogen pipeline networks expand, many of the same construction and operating features of natural gas networks would be replicated. As a result, the description of hydrogen pipelines will be very similar to that of natural gas pipelines

  15. Effects of hydrogen atoms on surface conductivity of diamond film

    SciTech Connect (OSTI)

    Liu, Fengbin Cui, Yan; Qu, Min; Di, Jiejian

    2015-04-15

    To investigate the effects of surface chemisorbed hydrogen atoms and hydrogen atoms in the subsurface region of diamond on surface conductivity, models of hydrogen atoms chemisorbed on diamond with (100) orientation and various concentrations of hydrogen atoms in the subsurface layer of the diamond were built. By using the first-principles method based on density functional theory, the equilibrium geometries and densities of states of the models were studied. The results showed that the surface chemisorbed hydrogen alone could not induce high surface conductivity. In addition, isolated hydrogen atoms in the subsurface layer of the diamond prefer to exist at the bond centre site of the C-C bond. However, such a structure would induce deep localized states, which could not improve the surface conductivity. When the hydrogen concentration increases, the C-H-C-H structure and C-3H{sub bc}-C structure in the subsurface region are more stable than other configurations. The former is not beneficial to the increase of the surface conductivity. However, the latter would induce strong surface states near the Fermi level, which would give rise to high surface conductivity. Thus, a high concentration of subsurface hydrogen atoms in diamond would make significant contributions to surface conductivity.

  16. Hydrogen delivery technology roadmap

    SciTech Connect (OSTI)

    None, None

    2005-11-15

    Document describing plan for research into and development of hydrogen delivery technology for transportation applications.

  17. Hydrogen Compatibility of Materials

    Broader source: Energy.gov [DOE]

    Presentation slides from the Energy Department webinar, Hydrogen Compatibility of Materials, held August 13, 2013.

  18. Safetygram #9- Liquid Hydrogen

    Broader source: Energy.gov [DOE]

    Hydrogen is colorless as a liquid. Its vapors are colorless, odorless, tasteless, and highly flammable.

  19. Hydrogen Generator Appliance

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    J slide presentation: hydrogen Generator appliance Gus Block, Nuvera Fuel Cells

  20. Hydrogen desorption from hydrogen fluoride and remote hydrogen plasma cleaned silicon carbide (0001) surfaces

    SciTech Connect (OSTI)

    King, Sean W. Tanaka, Satoru; Davis, Robert F.; Nemanich, Robert J.

    2015-09-15

    Due to the extreme chemical inertness of silicon carbide (SiC), in-situ thermal desorption is commonly utilized as a means to remove surface contamination prior to initiating critical semiconductor processing steps such as epitaxy, gate dielectric formation, and contact metallization. In-situ thermal desorption and silicon sublimation has also recently become a popular method for epitaxial growth of mono and few layer graphene. Accordingly, numerous thermal desorption experiments of various processed silicon carbide surfaces have been performed, but have ignored the presence of hydrogen, which is ubiquitous throughout semiconductor processing. In this regard, the authors have performed a combined temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy (XPS) investigation of the desorption of molecular hydrogen (H{sub 2}) and various other oxygen, carbon, and fluorine related species from ex-situ aqueous hydrogen fluoride (HF) and in-situ remote hydrogen plasma cleaned 6H-SiC (0001) surfaces. Using XPS, the authors observed that temperatures on the order of 7001000?C are needed to fully desorb C-H, C-O and Si-O species from these surfaces. However, using TPD, the authors observed H{sub 2} desorption at both lower temperatures (200550?C) as well as higher temperatures (>700?C). The low temperature H{sub 2} desorption was deconvoluted into multiple desorption states that, based on similarities to H{sub 2} desorption from Si (111), were attributed to silicon mono, di, and trihydride surface species as well as hydrogen trapped by subsurface defects, steps, or dopants. The higher temperature H{sub 2} desorption was similarly attributed to H{sub 2} evolved from surface O-H groups at ?750?C as well as the liberation of H{sub 2} during Si-O desorption at temperatures >800?C. These results indicate that while ex-situ aqueous HF processed 6H-SiC (0001) surfaces annealed at <700?C remain terminated by some surface CO and SiO bonding, they may

  1. Advanced Hydrogen Turbine Development

    SciTech Connect (OSTI)

    Joesph Fadok

    2008-01-01

    advanced hydrogen turbine that meets the aggressive targets set forth for the advanced hydrogen turbine, including increased rotor inlet temperature (RIT), lower total cooling and leakage air (TCLA) flow, higher pressure ratio, and higher mass flow through the turbine compared to the baseline. Maintaining efficiency with high mass flow Syngas combustion is achieved using a large high AN2 blade 4, which has been identified as a significant advancement beyond the current state-of-the-art. Preliminary results showed feasibility of a rotor system capable of increased power output and operating conditions above the baseline. In addition, several concepts were developed for casing components to address higher operating conditions. Rare earth modified bond coat for the purpose of reducing oxidation and TBC spallation demonstrated an increase in TBC spallation life of almost 40%. The results from Phase 1 identified two TBC compositions which satisfy the thermal conductivity requirements and have demonstrated phase stability up to temperatures of 1850 C. The potential to join alloys using a bonding process has been demonstrated and initial HVOF spray deposition trials were promising. The qualitative ranking of alloys and coatings in environmental conditions was also performed using isothermal tests where significant variations in alloy degradation were observed as a function of gas composition. Initial basic system configuration schematics and working system descriptions have been produced to define key boundary data and support estimation of costs. Review of existing materials in use for hydrogen transportation show benefits or tradeoffs for materials that could be used in this type of applications. Hydrogen safety will become a larger risk than when using natural gas fuel as the work done to date in other areas has shown direct implications for this type of use. Studies were conducted which showed reduced CO{sub 2} and NOx emissions with increased plant efficiency. An approach to

  2. Improved Hydrogen Gas Getters for TRU Waste -- Final Report

    SciTech Connect (OSTI)

    Mark Stone; Michael Benson; Christopher Orme; Thomas Luther; Eric Peterson

    2005-09-01

    Alpha radiolysis of hydrogenous waste and packaging materials generates hydrogen gas in radioactive storage containers. For that reason, the Nuclear Regulatory Commission limits the flammable gas (hydrogen) concentration in the Transuranic Package Transporter-II (TRUPACT-II) containers to 5 vol% of hydrogen in air, which is the lower explosion limit. Consequently, a method is needed to prevent the build up of hydrogen to 5 vol% during the storage and transport of the TRUPACT-II containers (up to 60 days). One promising option is the use of hydrogen getters. These materials scavenge hydrogen from the gas phase and irreversibly bind it in the solid phase. One proven getter is a material called 1,4-bis (phenylethynyl) benzene, or DEB, characterized by the presence of carbon-carbon triple bonds. Carbon may, in the presence of suitable precious metal catalysts such as palladium, irreversibly react with and bind hydrogen. In the presence of oxygen, the precious metal may also eliminate hydrogen by catalyzing the formation of water. This reaction is called catalytic recombination. DEB has the needed binding rate and capacity for hydrogen that potentially could be generated in the TRUPACT II. Phases 1 and 2 of this project showed that uncoated DEB performed satisfactorily in lab scale tests. Based upon these results, Phase 3, the final project phase, included larger scale testing. Test vessels were scaled to replicate the ratio between void space in the inner containment vessel of a TRUPACT-II container and a payload of seven 55-gallon drums. The tests were run with an atmosphere of air for 63.9 days at ambient temperature (15-27C) and a scaled hydrogen generation rate of 2.60E-07 moles per second (0.35 cc/min). A second type of getter known as VEI, a proprietary polymer hydrogen getter characterized by carbon-carbon double bonds, was also tested in Phase 3. Hydrogen was successfully gettered by both getter systems. Hydrogen concentrations remained below 5 vol% (in air

  3. Composition for absorbing hydrogen

    DOE Patents [OSTI]

    Heung, Leung K.; Wicks, George G.; Enz, Glenn L.

    1995-01-01

    A hydrogen absorbing composition. The composition comprises a porous glass matrix, made by a sol-gel process, having a hydrogen-absorbing material dispersed throughout the matrix. A sol, made from tetraethyl orthosilicate, is mixed with a hydrogen-absorbing material and solidified to form a porous glass matrix with the hydrogen-absorbing material dispersed uniformly throughout the matrix. The glass matrix has pores large enough to allow gases having hydrogen to pass through the matrix, yet small enough to hold the particles dispersed within the matrix so that the hydrogen-absorbing particles are not released during repeated hydrogen absorption/desorption cycles.

  4. Composition for absorbing hydrogen

    DOE Patents [OSTI]

    Heung, L.K.; Wicks, G.G.; Enz, G.L.

    1995-05-02

    A hydrogen absorbing composition is described. The composition comprises a porous glass matrix, made by a sol-gel process, having a hydrogen-absorbing material dispersed throughout the matrix. A sol, made from tetraethyl orthosilicate, is mixed with a hydrogen-absorbing material and solidified to form a porous glass matrix with the hydrogen-absorbing material dispersed uniformly throughout the matrix. The glass matrix has pores large enough to allow gases having hydrogen to pass through the matrix, yet small enough to hold the particles dispersed within the matrix so that the hydrogen-absorbing particles are not released during repeated hydrogen absorption/desorption cycles.

  5. Electron trap level of hydrogen incorporated nitrogen vacancies in silicon nitride

    SciTech Connect (OSTI)

    Sonoda, Ken'ichiro Tsukuda, Eiji; Tanizawa, Motoaki; Yamaguchi, Yasuo

    2015-03-14

    Hydrogen incorporation into nitrogen vacancies in silicon nitride and its effects on electron trap level are analyzed using simulation based on density functional theory with temperature- and pressure-dependent hydrogen chemical potential. If the silicon dangling bonds around a nitrogen vacancy are well separated each other, hydrogen incorporation is energetically stable up to 900 °C, which is in agreement with the experimentally observed desorption temperature. On the other hand, if the dangling bonds strongly interact, the incorporation is energetically unfavorable even at room temperature because of steric hindrance. An electron trap level caused by a nitrogen vacancy becomes shallow by the hydrogen incorporation. An electron is trapped in a deep level created by a silicon dangling bond before hydrogen incorporation, whereas it is trapped in a shallow level created by an anti-bonding state of a silicon-silicon bond after hydrogen incorporation. The simulation results qualitatively explain the experiment, in which reduced hydrogen content in silicon nitride shows superior charge retention characteristics.

  6. Hydrogen Pipeline Discussion

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    praxair.com Copyright © 2003, Praxair Technology, Inc. All rights reserved. Hydrogen Pipeline Discussion BY Robert Zawierucha, Kang Xu and Gary Koeppel PRAXAIR TECHNOLOGY CENTER TONAWANDA, NEW YORK DOE Hydrogen Pipeline Workshop Augusta, GA August 2005 2 Introduction Regulatory and technical groups that impact hydrogen and hydrogen systems ASME, DOE, DOT etc, Compressed Gas Association activities ASTM TG G1.06.08 Hydrogen pipelines and CGA-5.6 Selected experience and guidance Summary and

  7. Overview of Two Hydrogen Energy Storage Studies: Wind Hydrogen in California and Blending in Natural Gas Pipelines (Presentation)

    SciTech Connect (OSTI)

    Melaina, M. W.

    2013-05-01

    This presentation provides an overview of two NREL energy storage studies: Wind Hydrogen in California: Case Study and Blending Hydrogen Into Natural Gas Pipeline Networks: A Review of Key Issues. The presentation summarizes key issues, major model input assumptions, and results.

  8. Smart interfacial bonding alloys

    SciTech Connect (OSTI)

    R. Q. Hwang; J. C. Hamilton; J. E. Houston

    1999-04-01

    The goal of this LDRD was to explore the use of the newly discovered strain-stabilized 2-D interfacial alloys as smart interface bonding alloys (SIBA). These materials will be used as templates for the heteroepitaxial growth of metallic thin films. SIBA are formed by two metallic components which mix at an interface to relieve strain and prevent dislocations from forming in subsequent thin film growth. The composition of the SIBA is determined locally by the amount of strain, and therefore can react smartly to areas of the highest strain to relieve dislocations. In this way, SIBA can be used to tailor the dislocation structure of thin films. This project included growth, characterization and modeling of films grown using SIBA templates. Characterization will include atomic imaging of the dislocations structure, measurement of the mechanical properties of the film using interface force microscopy (IFM) and the nanoindenter, and measurement of the electronic structure of the SIBA with synchrotron photoemission. Resistance of films to sulfidation and oxidation will also be examined. The Paragon parallel processing computer will be used to calculate the structure of the SIBA and thin films in order to develop ability to predict and tailor SIBA and thin film behavior. This work will lead to the possible development of a new class of thin film materials with properties tailored by varying the composition of the SIBA, serving as a buffer layer to relieve the strain between the substrate and the thin film. Such films will have improved mechanical and corrosion resistance allowing application as protective barriers for weapons applications. They will also exhibit enhanced electrical conductivity and reduced electromigration making them particularly suitable for application as interconnects and other electronic needs.

  9. Method of bonding

    DOE Patents [OSTI]

    Saller, deceased, Henry A. (late of Columbus, OH); Hodge, Edwin S. (Columbus, OH); Paprocki, Stanley J. (Columbus, OH); Dayton, Russell W. (Columbus, OH)

    1987-12-01

    1. A method of making a fuel-containing structure for nuclear reactors, comprising providing an assembly comprising a plurality of fuel units; each fuel unit consisting of a core plate containing thermal-neutron-fissionable material, sheets of cladding metal on its bottom and top surfaces, said cladding sheets being of greater width and length than said core plates whereby recesses are formed at the ends and sides of said core plate, and end pieces and first side pieces of cladding metal of the same thickness as the core plate positioned in said recesses, the assembly further comprising a plurality of second side pieces of cladding metal engaging the cladding sheets so as to space the fuel units from one another, and a plurality of filler plates of an acid-dissolvable nonresilient material whose melting point is above 2000.degree. F., each filler plate being arranged between a pair of said second side pieces and the cladding plates of two adjacent fuel units, the filler plates having the same thickness as the second side pieces; the method further comprising enclosing the entire assembly in an envelope; evacuating the interior of the entire assembly through said envelope; applying inert gas under a pressure of about 10,000 psi to the outside of said envelope while at the same time heating the assembly to a temperature above the flow point of the cladding metal but below the melting point of any material of the assembly, whereby the envelope is pressed against the assembly and integral bonds are formed between plates, sheets, first side pieces, and end pieces and between the sheets and the second side pieces; slowly cooling the assembly to room temperature; removing the envelope; and dissolving the filler plates without attacking the cladding metal.

  10. Method for vacuum fusion bonding

    DOE Patents [OSTI]

    Ackler, Harold D.; Swierkowski, Stefan P.; Tarte, Lisa A.; Hicks, Randall K.

    2001-01-01

    An improved vacuum fusion bonding structure and process for aligned bonding of large area glass plates, patterned with microchannels and access holes and slots, for elevated glass fusion temperatures. Vacuum pumpout of all components is through the bottom platform which yields an untouched, defect free top surface which greatly improves optical access through this smooth surface. Also, a completely non-adherent interlayer, such as graphite, with alignment and location features is located between the main steel platform and the glass plate pair, which makes large improvements in quality, yield, and ease of use, and enables aligned bonding of very large glass structures.