In Tae Bae、Donald A. Tryk、Daniel A. Scherson1998-04-29The Journal of Physical Chemistry B
Electronic aspects of an iron porphyrin, 5,10,15,20-tetrakis(4-methoxyphenyl)-21 H,23 H -porphine iron(III) chloride (FeTMPPCl) molecularly dispersed on a high area carbon black (Black Pearls 2000, BP) and then heat-treated (or thermally activated) at 800 °C in a flowing inert atmosphere, were investigated in situ in…
Electrocatalysts for Energy ConversionElectrochemical sensors and biosensorsPorphyrin and Phthalocyanine Chemistry
G. Grinstein、Yuhai Tu、J. Tersoff1998-04-29arXiv
We analyze the stability of a planar solid-solid interface at which a chemical reaction occurs. Examples include oxidation, nitridation, or silicide formation. Using a continuum model, including a general formula for the stress-dependence of the reaction rate, we show that stress effects can render a planar interface…
Materials Science
Goetz S. Uhrig1998-04-29arXiv
The validity of the adiabatic approach to spin-Peierls transitions is assessed. An alternative approach is developed which maps the initial magneto-elastic problem to an effective magnetic problem only. Thus the equivalence of magneto-elastic solitons and magnetic spinons is shown. No soft phonon is required for the t…
Materials ScienceStrongly Correlated Electrons
Mingqi Zhao、Li Sun、Richard M. Crooks1998-04-29OpenAlex
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTPreparation of Cu Nanoclusters within Dendrimer TemplatesMingqi Zhao, Li Sun, and Richard M. CrooksView Author Information Department of Chemistry, P.O. Box 300012 Texas A&M University, College Station, Texas 77842-3012 Cite this: J. Am. Chem. Soc. 1998, 120, 19, 4877–…
Gold and Silver Nanoparticles Synthesis and ApplicationsDendrimers and Hyperbranched PolymersNanocluster Synthesis and Applications
Komandur V. R. Chary、Thallada Bhaskar、Gurram Kishan 等 4 位作者1998-04-28The Journal of Physical Chemistry B
A series of molybdena catalysts supported on anatase titania with Mo loadings ranging from 2 to 12 wt % were investigated by 1 H MAS NMR, XRD, ESR, and oxygen chemisorption. 1 H MAS NMR spectra reveals the presence of two types of OH groups (acidic and basic) on TiO 2 . Dispersion of molybdena was determined by the ox…
Catalytic Processes in Materials ScienceCatalysis and Hydrodesulfurization StudiesCatalysis and Oxidation Reactions
Takashi Yamamoto、Takafumi Shido、Shinji Inagaki 等 5 位作者1998-04-28The Journal of Physical Chemistry B
A robust trigonal prismatic cluster anion [Pt 3 (CO) 6 ] 5 2- (ν CO = 2078, 1878 cm -1; λ max = 405 and 702 nm; R 1 (Pt−Pt) = 2.68 Å (CN = 2.0); R 2 (Pt−Pt) = 3.08 Å (CN = 1.5)) is selectively synthesized in the ordered hexagonal channel of FSM-16 by the reductive carbonylation of H 2 PtCl 6 /NR 4 + /FSM-16 under a CO…
Catalytic Processes in Materials ScienceMesoporous Materials and CatalysisCatalysis and Oxidation Reactions
Karl M. Kadish、Ning Guo、Eric Van Caemelbecke 等 11 位作者1998-04-28Inorganic Chemistry
Four unsymmetrical covalently linked porphyrin dimers were synthesized, and their electrochemical, spectroelectrochemical, and/or photophysical properties were examined. The investigated compounds are represented as M[ p -(TPP-DEHMP)]M and M[ m -(TPP-DEHMP)]M (M = H 2, Zn), where p -(TPP-DEHMP) is the tetraanion of 1-…
Photosynthetic Processes and MechanismsPorphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer Studies
Jaideep Chatterjee、Alex Nikolov、Darsh T. Wasan1998-04-28Industrial & Engineering Chemistry Research
This paper discusses the dynamic interfacial tension (IFT) variation in a system containing an acidic oil in contact with an alkaline solution which may contain a preformed surfactant. A modified technique similar, in principle, to the sessile drop technique is used for monitoring the dynamic IFT which is in the ultra…
Surface Modification and SuperhydrophobicitySurfactants and Colloidal SystemsPolymer Surface Interaction Studies
Christopher L. Cahill、Younghee Ko、Jonathan C. Hanson 等 5 位作者1998-04-28Chemistry of Materials
The structure of QUI-MnGS-1 has been determined from single-crystal X-ray diffraction on a ∼0.03 × 0.03 × 0.02 mm sample using synchrotron radiation. This material [(C 7 H 13 N)Mn 0.25 Ge 1.75 S 4 ·H 2 O] crystallizes in space group I 4̄2 d with unit cell a = 11.581(1) and c = 18.741(3) Å. The extended framework of th…
Metal-Organic Frameworks: Synthesis and ApplicationsCrystal Structures and PropertiesInorganic Fluorides and Related Compounds
Florent Boucher、Roger Rousseau1998-04-28Inorganic Chemistry
The compound Cs 3 Te 22 is well-known for its interesting structural features. It contains both a unique 2,3-connected defect square Te sheet and Te 8 rings. For a better understanding of the structure and bonding, the band structure of Cs 3 Te 22 is examined by means of the ab initio tight-binding linear muffin-tin o…
Chalcogenide Semiconductor Thin FilmsCrystal Structures and PropertiesSolid-state spectroscopy and crystallography
C. Haas、Joost P.H. Drenth1998-04-28The Journal of Physical Chemistry B
The phase diagram of a protein−water system is described with a simple model with parameters for the interaction between protein molecules in the liquid and in the solid phase. The model reproduces essential features of the phase diagram, such as the (metastable) liquid−liquid immiscibility region and the triple point…
Enzyme Structure and FunctionCrystallization and Solubility Studiesnanoparticles nucleation surface interactions
Keiji Nakajima、Atsuko Yamashita、Hiroyuki Akama 等 8 位作者1998-04-28Proceedings of the National Academy of Sciences
A pair of tropinone reductases (TRs) share 64% of the same amino acid residues and belong to the short-chain dehydrogenase/reductase family. In the synthesis of tropane alkaloids in several medicinal plants, the TRs reduce a carbonyl group of an alkaloid intermediate, tropinone, to hydroxy groups with different diaste…
Carbohydrate Chemistry and SynthesisEnzyme Structure and FunctionPorphyrin Metabolism and Disorders
Paula M.D. Fitzgerald、Joseph K. Wu、Jeffrey H. Toney1998-04-28Biochemistry
As part of a structure-aided effort to design clinically useful inhibitors of metallo-beta-lactamases, the X-ray crystal structure of a complex between the metallo-beta-lactamase from Bacteroides fragilis and 4-morpholinoethanesulfonic acid (MES) has been determined and a model for the structure has been refined to a…
Protein Structure and DynamicsMicrobial Natural Products and BiosynthesisEnzyme Structure and Function
Mougang Hu、Nicole Brasseur、S. Zeki Yıldız 等 5 位作者1998-04-28Journal of Medicinal Chemistry
A series of benzyl-substituted phthalonitriles, substituted at the 3-, 4-, and 4,5-positions, underwent varied condensations with phthalonitrile to give a series of protected (monohydroxy- and polyhydroxyphthalocyaninato)zinc(II) derivatives which were readily cleaved to give several hydroxyphthalocyanines (ZnPc) (pht…
Nanoplatforms for cancer theranosticsPorphyrin and Phthalocyanine ChemistryPhotodynamic Therapy Research Studies
Namyong Y. Kim、Paul E. Laibinis1998-04-28Journal of the American Chemical Society
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTDerivatization of Porous Silicon by Grignard Reagents at Room TemperatureNamyong Y. Kim and Paul E. LaibinisView Author Information Departments of Chemistry and Chemical Engineering Massachusetts Institute of Technology Cambridge, Massachusetts 02139 Cite this: J. Am.…
Semiconductor materials and devicesSilicon Nanostructures and PhotoluminescenceDielectric properties of ceramics
Laurent E. Cartier、Takumi Okihara、Bernard Lotz1998-04-28Macromolecules
The crystal structure of syndiotactic polystyrene (sPS) in its stable α form (a so-called “superstructure” named α‘‘) is reevaluated. As shown by all previous investigations, the trigonal unit cell contains three triplets of extended sPS chains. The azimuthal orientation of the three triplets is shown to differ from t…
Polymer crystallization and propertiesCrystallography and molecular interactionsSynthesis and Properties of Aromatic Compounds
M. J. Gerald Lesley、Alden D. Woodward、Nicholas J. Taylor 等 10 位作者1998-04-28Chemistry of Materials
A series of neutral pyridyl adducts involving the strong Lewis acids BF 3 and B(C 6 F 5 ) 3 has been prepared, and their second-order nonlinear optical coefficients (EFISH method) have been examined. The formation of the pyridyl−boron bond leads to enhancement of the dipole moments and second-order NLO coefficients (β…
Crystal Structures and PropertiesNonlinear Optical Materials ResearchSolid-state spectroscopy and crystallography
Donatella Carbonera、Marilena Di Valentin、Carlo Corvaja 等 10 位作者1998-04-28Journal of the American Chemical Society
The photochemistry of a molecular triad consisting of a porphyrin (P) covalently linked to a carotenoid polyene (C) and a fullerene derivative (C 60 ) has been studied at 20 K by time-resolved EPR spectroscopy following laser excitation. Excitation of the porphyrin moiety yields C− 1 P−C 60, which decays by photoinduc…
Photosynthetic Processes and MechanismsPorphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer Studies
R. Hilfer1998-04-28arXiv
The established macroscopic equations of motion for two phase immiscible displacement in porous media are known to be physically incomplete because they do not contain the surface tension and surface areas governing capillary phenomena. Therefore a more general system of macroscopic equations is derived here which inc…
Materials Science
Yves Grohens、Maurice Brogly、Clorinthe Labbe 等 5 位作者1998-04-28Langmuir
The glass transition temperature ( T g ) of layers of stereoregular poly(methyl methacrylate) (PMMA) spin-cast on silicon and aluminum surfaces has been investigated by ellipsometry. The interfacial specific interactions were highlighted and quantified by infrared reflection absorption spectroscopy. It was found that…
Liquid Crystal Research AdvancementsMaterial Dynamics and PropertiesTheoretical and Computational Physics