Marlys J. M. Nesset、Sheng Cai、Tatjana Kh. Shokhireva 等 8 位作者2000-01-14Inorganic Chemistry
The perchloratoiron(III) complexes of a series of 2,6-disubstituted tetraphenylporphyrin ligands, where the 2,6-phenyl substituents were -H, -F, -Cl, -Br, or -OMe, as well as two 2,4,6-phenyl-substituted complexes, where the substituents were -Me and -OMe, have been investigated as a function of temperature by 1H NMR…
Porphyrin and Phthalocyanine ChemistryMagnetism in coordination complexesLuminescence and Fluorescent Materials
Dominique Madern、Christine Ebel、Moshe Mevarech 等 6 位作者2000-01-14Biochemistry
L-Malate (MalDH) and L-lactate (LDH) dehydrogenases belong to the same family of NAD-dependent enzymes. LDHs are tetramers, whereas MalDHs can be either dimeric or tetrameric. To gain insight into molecular relationships between LDHs and MalDHs, we studied folding intermediates of a mutant of the LDH-like MalDH (a pro…
Hemoglobin structure and functionEnzyme Structure and FunctionProtein Structure and Dynamics
David J. Abdallah、Richard G. Weiss2000-01-14Chemistry of Materials
The phase properties of 14 tetra- n -alkylammonium and -phosphonium salts with chloride, bromide, iodide, and perchlorate as anions and alkyl chain lengths from heptyl to octadecyl have been examined as neat solids and as gelators in thermally reversible organogels. These gelator structures are among the simplest inve…
Lipid Membrane Structure and BehaviorMolecular Sensors and Ion DetectionSupramolecular Self-Assembly in Materials
Mirko Vitiello、Núria López、Francesc Illas 等 4 位作者2000-01-14The Journal of Physical Chemistry A
The interaction of H 2 with the defect sites of the SiO 2 surface has been studied by means of gradient-corrected density functional theory calculations on cluster models. The mechanism of hydrogen dissociation, the energy of reactants and products, and the corresponding activation energies and transition states have…
Semiconductor materials and devicesGlass properties and applicationsLuminescence Properties of Advanced Materials
Takakuni Hirabayashi、Yutaka Kameo、Masato Myodo2000-01-14Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE
In the research and development of various advanced technologies needed for decontamination and decommissioning of nuclear facilities, laser was applied to decontamination of metal and concrete surfaces and to cutting of large metal of low level radioactive waste. (a) Laser decontamination for metal waste: Metal waste…
Graphite, nuclear technology, radiation studies
Stéphane Richard、Dominique Madern、Elsa D. Garcin 等 4 位作者2000-01-14Biochemistry
Previous biophysical studies of tetrameric malate dehydrogenase from the halophilic archaeon Haloarcula marismortui (Hm MalDH) have revealed the importance of protein-solvent interactions for its adaptation to molar salt conditions that strongly affect protein solubility, stability, and activity, in general. The struc…
Photosynthetic Processes and MechanismsEnzyme Production and CharacterizationEnzyme Structure and Function
Thierry Toupance、M. Kermarec、Catherine Louis2000-01-14The Journal of Physical Chemistry B
The size of metal copper particles supported on silica was studied as a function of the following parameters: the preparation route, the nature of the metallic precursor, the copper content, and the thermal pretreatments before reduction. Two modes of preparation were investigated: (i) incipient wetness impregnation w…
Catalytic Processes in Materials ScienceNanomaterials for catalytic reactionsMesoporous Materials and Catalysis
S. Rajesh、G. Ananthakrishna2000-01-14arXiv
The dynamics of a model, originally proposed for a type of instability in plastic flow, has been investigated in detail. The bifurcation portrait of the system in two physically relevant parameters exhibits a rich variety of dynamical behaviour, including period bubbling and period adding or Farey sequences. The compl…
Materials Sciencenlin.CD
A. M. R. Teixeira、P. T. C. Freire、A. J. D. Moreno 等 7 位作者2000-01-14arXiv
Pressure-dependent Raman scattering studies in the range 0.0 -- 32 kbar were carried out in L-alanine in order to investigate its external mode phonon spectra in relation to the phase transitions in the crystal. A careful analysis of the spectra shows that the low-energy Raman modes exhibit variation both in frequency…
Materials Science
D. Passerone、F. Ercolessi、E. Tosatti2000-01-14arXiv
Deposition/removal of metal atoms on the hex reconstructed (100) surface of Au, Pt and Ir should present intriguing aspects, since a new island implies hex -> square deconstruction of the substrate, and a new crater the square -> hex reconstruction of the uncovered layer. To obtain a microscopic understanding of how i…
cond-mat.stat-mechMaterials Science
Igor Luzinov、D Julthongpiput、Hauke Malz 等 5 位作者2000-01-14Macromolecules
Carboxylic acid- and anhydride-terminated polystyrenes of different molecular weights from 4500 to 672 000 were grafted from melt onto silicon substrates modified with epoxysilane monolayer . The grafted chains are densely packed with a density close to the known value for the bulk material. The tethered polymer layer…
Polymer Surface Interaction StudiesMolecular Junctions and NanostructuresSurface Modification and Superhydrophobicity
Fan Zhong、Z. D. Wang2000-01-14arXiv
We analyze the symmetry of all possible magnetic structures of bilayered manganites La_{2-2x}Sr_{1+2x}Mn_2O_7 with doping 0.3 <= x < 0.5 and formulate a corresponding Landau theory of the phase transitions involved. It is shown that canting of spins is not allowed at x=0.3 though is at x=0.4. The observed magnetic ref…
Materials ScienceStrongly Correlated Electrons
Hans R. Kricheldorf、Ingrid Kreiser‐Saunders、Andrea Stricker2000-01-14OpenAlex
Sn(II)2−ethylhexanoate (SnOct 2 ) was reacted with 2 equiv of benzyl alcohol at 20 °C, and a liberation of octanoic acid in a rapid equilibration was found. When the temperature was raised to 180 °C in steps of 40 °C, esterification of benzyl alcohol and octanoic acid was observed up to a conversion of 90%. This ester…
Carbon dioxide utilization in catalysisbiodegradable polymer synthesis and properties
Willem K. Kegel、and Alfons van Blaaderen2000-01-14OpenAlex
The real-space dynamics in a model system of colloidal hard spheres was studied by means of time-resolved fluorescence confocal scanning microscopy. Direct experimental evidence for the presence of dynamical heterogeneities in a dense liquid was obtained from an analysis of particle trajectories in two-dimensional sli…
Material Dynamics and PropertiesPhase Equilibria and ThermodynamicsThermodynamic properties of mixtures
Ke Deng、Jinlong Yang、C. T. Chan2000-01-13Physical Review A
The polarizabilities of Si clusters with 9 to 28 atoms are calculated using a density functional cluster method. The atomic geometries are based on those carefully optimized by energy minimization. The polarizability shows fairly irregular variation with cluster size, but all calculated values are higher than the pola…
Semiconductor materials and devicesQuantum Dots Synthesis And PropertiesSilicon Nanostructures and Photoluminescence
Gianfranco Durin、Stefano Zapperi2000-01-13arXiv
We investigate the scaling properties of the Barkhausen effect, recording the noise in several soft ferromagnetic materials: polycrystals with different grain sizes and amorphous alloys. We measure the Barkhausen avalanche distributions and determine the scaling exponents. In the limit of vanishing external field rate…
cond-mat.stat-mechMaterials Science
F. Comas、Nelson Studart2000-01-13arXiv
We report calculations of high electric field transport for the case of a strained Si/GeSi double heterostructure (DHS) considering transport along the Si channel and by applying the analytical Fokker-Planck approach (FPA), where the process is modeled as drift-diffusion in energy space. We limit ourselves to electron…
Materials Science
V. B. Belyaev、M. B. Miller、A. K. Motovilov 等 10 位作者2000-01-13arXiv
Experimental search for molecular-nuclear transitions H_2O\to^{18}Ne^*(4.522,1^-)\to^{18}F\to^{18}O in water molecules was carried out. The measurements were performed in a low-background laboratory at the Baksan Neutrino Observatory. Under the assumption that the above transitions take place, the estimate for the hal…
nucl-exnucl-thMaterials Science
S. S. A. Razee、J. B. Staunton、B. Ginatempo 等 5 位作者2000-01-13arXiv
The cubic lattice symmetry of ferromagnetic homogeneously disordered alloys is when a compositional modulation is imposed. This can have a profound influence on the magnetocrystalline anisotropy energy (MAE). We describe our ab-initio theory of this effect and use the framework of concentration waves with the electron…
Materials Science
Seiji Miyashita、Keiji Saito、Hiroto Kobayashi 等 4 位作者2000-01-13arXiv
In discrete energy structure of nanoscale magnets, nonadiabatic transitions at avoided level crossings lead to fundamental processes of dynamics of magnetizations. The thermal environment causes dissipative effects on these processes. In this paper we review the features of the nonadiabatic transition and the influenc…
Materials Science