Dennis P. Arnold、David A. James1997-05-01The Journal of Organic Chemistry
Porphyrin dimers linked in the meso -positions by bridges containing alkynes conjugated with the porphyrin π-systems display highly perturbed electronic absorption spectra. We have prepared a series of such dimers using meso -ethynyl nickel(II) octaethylporphyrin as the primary building block. The bridging units inclu…
Porphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer StudiesMetal-Catalyzed Oxygenation Mechanisms
Yiping Zhang、Pamela J. Zapf、Linda M. Meyer 等 5 位作者1997-05-01Inorganic Chemistry
The hydrothermal reactions of vanadium oxide and molybdenum oxide starting materials with divalent first-row transition metal cations in the presence of nitrogen donor chelating ligands yield the heterometallic hexanuclear clusters [{Zn(bipy)(2)}(2)V(4)O(12)] (2), [{Zn(phen)(2)}(2)V(4)O(12)].H(2)O (3.H(2)O), and [{Ni(…
Metal-Organic Frameworks: Synthesis and ApplicationsPolyoxometalates: Synthesis and ApplicationsAdvanced Nanomaterials in Catalysis
Michele Laus、A. S. Angeloni、Oriano Francescangeli 等 5 位作者1997-05-01Macromolecular Symposia
Abstract The peculiar liquid crystalline behavior of two poly(urethane‐ester)s TDI‐C6C4 and TDI‐C6C8 is reported. Evidence is provided of the formation of two nematic mesophases, a cybotactic nematic and a conventional nematic mesophase, in TDI‐C6C8 and of one cybotactic nematic mesophase in TDI‐C6C4. IR spectroscopy…
Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsSynthesis and Properties of Aromatic Compounds
Lorna J. Gibson、Michael F. Ashby1997-05-01Cambridge University Press eBooks
Introduction and synopsis Foams can be made out of almost anything: metals, plastics, ceramics, glasses, and even composites. Their properties depend on two separate sets of parameters. There are those which describe the geometric structure of the foam – the size and shape of the cells, the way in which matter is dist…
Asphalt Pavement Performance EvaluationCellular and Composite StructuresPolymer composites and self-healing
Jens Eggers1997-05-01Physikalische Blätter
Abstract Die Wirkungsweise von Rasensprengern, Parfumzerstäubern oder Tintenstrahldruckern beruht auf der Oberflächenspannung. Diese führt dazu, daß sich ein Flüssigkeitsstrahl unter Verringerung der Oberfläche einschnürt und Tropfen bildet. In der Nähe des singulären Punktes, in dem sich ein Tropfen abtrennt, gelten…
Surface Modification and SuperhydrophobicityFluid Dynamics and Thin FilmsPlant Surface Properties and Treatments
P. Predeep、N. S. Saxena1997-05-01Physica Scripta
Thermal conductivity and thermal diffusivity of three rare earth oxide powders (Gadolinium oxide, Samarium oxide and Yttrium oxide) are measured experimentally using Transient Plane Source (TPS) technique at ambient temperature. An attempt has been made to accommodate the effect of porosity of the powders on thermal c…
Numerical methods in inverse problemsThermal properties of materialsRadiative Heat Transfer Studies
Gaboury Benoit、Tim F. Rozan、Richard April1997-05-01Soil Science Society of America Journal
Abstract Soil weathering is an important source of nutrient cations and P for development of forested ecosystems, but the rates at which these nutrients are released are not well known. Measurement of weathering products can be used in long‐term (5–10 yr) mesocosm studies to evaluate soil weathering rates. In this stu…
Geochemistry and Elemental AnalysisClay minerals and soil interactionsMine drainage and remediation techniques
Владимир И. Минкин、V. N. Komissarov1997-05-01Molecular crystals and liquid crystals science technology. Section A, Molecular crystals and liquid crystals/Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals
A new class of photochromic compounds, derivatives of 2,3-dihydro-2-spiro-4′-(2′,6′-di-tert-butylcyclohexadienon-2′,5′- one) erimidine is described and their photochromic and thermochromic rearrangements described.
Photochromic and Fluorescence ChemistryBioactive Compounds and Antitumor AgentsSynthesis of Organic Compounds
Chad R. Snyder、Hervé Marand1997-05-01Macromolecules
A previous study (Snyder, C. R.; Marand, H.; Mansfield, M. L. Macromolecules 1996, 29, 7508) by the authors suggested that, within the context of the Lauritzen−Hoffman secondary surface nucleation theory, the apportionment factor for the free energy of crystallization (ψ LH ) and the retardation factor due to transpor…
Polymer crystallization and propertiesPolymer Nanocomposites and PropertiesRheology and Fluid Dynamics Studies
Peter A. Tanner、Xia Shangda、Liu Yu-long 等 4 位作者1997-05-01Physical review. B, Condensed matter
Raman spectra have been recorded from 300--10 K for lanthanide hexachloroelpasolites, ${\mathrm{Cs}}_{2}$${\mathrm{NaLCl}}_{6}$. Electronic Raman-scattering intensity ratios have been calculated using Judd-Ofelt-Axe theory and are in reasonable agreement with experimental results, except for those cases where electron…
Glass properties and applicationsCrystal Structures and PropertiesSolid-state spectroscopy and crystallography
Hiromi Matsuhashi、Kenneth J. Klabunde1997-05-01Langmuir
The electron-donating property of Na metal-doped MgO (Na/MgO) was studied by the ESR technique. The spin concentration of (CO) n x - ((CO) 2 - and/or (CO) 6 3 - ) radicals formed from adsorbed CO on a Na/MgO surface was much higher than that of the surface paramagnetic center formed by an electron released from sodium…
Electronic and Structural Properties of OxidesMagnesium Oxide Properties and Applications
Virgil Percec1997-05-01Macromolecular Symposia
Abstract A brief discussion of selected synthetic strategies pursued in the field of molecular, macromolecular and supramolecular liquid crystals is made by reviewing some tandem historical events of the past 100 years of activity in this field. This survey will try to suggest the rational for the discovery, evolution…
Liquid Crystal Research AdvancementsSupramolecular Chemistry and ComplexesSurfactants and Colloidal Systems
W. D. J. Amilaprasadh Norbert、John W. Goodby、Michael Hird 等 4 位作者1997-05-01Liquid Crystals
The synthesis, mesophase morphology and transition temperatures of a series of 1,2,4,5-tetrasubstituted benzenes are described. The compounds have (4-tridecyloxyphenyl)carbonyloxy or (4-tridecyloxyphenyl)ethynyl as the peripheral substituents in all possible combinations ranging from the tetra-ester to the tetra-alkyn…
Liquid Crystal Research AdvancementsSynthesis and Properties of Aromatic CompoundsMolecular spectroscopy and chirality
Khalid Satori、Yoshinori Haga、R. Minatoya 等 5 位作者1997-05-01Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
We have investigated the effects of the sputter-induced roughness on the depth resolution Δz and on the interface position zc obtained by Auger electron spectroscopy (AES) depth profiling of a Ni/Cr multilayer and of an AlAs/GaAs superlattice. We also correlated the escape depth λ with Δz and zc. First, the sputter-in…
Semiconductor materials and devicesElectron and X-Ray Spectroscopy TechniquesIon-surface interactions and analysis
G.C. Montanari1997-05-01IEEE Electrical Insulation Magazine
Inference of ageing mechanisms becomes a very complex matter in insulations, where the presence of electrical field concentrations, temperature gradients, various insulating materials, inhomogeneities, etc., complicates tremendously any physical investigation. This paper focuses on recent developments in modeling insu…
High voltage insulation and dielectric phenomenaLightning and Electromagnetic PhenomenaPower Transformer Diagnostics and Insulation
Tse‐Chuan Chou、Shan-Van Lee1997-05-01Industrial & Engineering Chemistry Research
Epoxidation of oleic acid with oxygen in the presence of benzaldehyde using cobalt(II) tetraphenylporphyrin (Co 2+ -TPP) as catalyst was studied. The results show that high yield of epoxidized oleic acid is obtained by the liquid phase epoxidation of oleic acid in the presence of benzaldehyde using Co 2+ -TPP as catal…
Polymer composites and self-healingPorphyrin and Phthalocyanine ChemistryOxidative Organic Chemistry Reactions
J. Kasperek、M. Lenglet1997-05-01Revue de Métallurgie
Raman and FTIR reflectance spectroscopies have been used for the characterization of the following zinc corrosion products formed by atmospheric corrosion : (ε-Zn(OH)2, hydrozincite Zn5(CO3)2(OH)6, simonkolleite Zn5Cl2(OH)8,H2O and zinc sulfates ZnSO4,H2O, Zn4SO4(OH)6, 5H2O and Zn4SO4(OH)6,H2O. The samples to analyze…
Corrosion Behavior and InhibitionGas Sensing Nanomaterials and SensorsCultural Heritage Materials Analysis
P. Talába、Iva Sroková、Anna Ebringerová 等 5 位作者1997-05-01Journal of Carbohydrate Chemistry
In this paper is reported the partial hydrophobization of O-(2-sulfoethyl)cellulose (SEC) using 1-bromododecane, 1-bromodecane, and 1-bromododecane with cellulose sulfate (CS), respectively, and characterization of the reaction products by both elemental and spectral analyses. The surface tension, critical micelle con…
biodegradable polymer synthesis and properties
Victor S. Lusvardi、Keith G. Pierce、Mark A. Barteau1997-05-01Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
Previous temperature programmed desorption (TPD) experiments on reduced TiO2 (001) surfaces have demonstrated that alkynes are converted to the corresponding aromatic products with high selectivity. This reaction also represents the first example of catalytic assembly of carbon–carbon bonds on a metal oxide surface in…
Catalytic Processes in Materials ScienceCatalysis and Hydrodesulfurization StudiesCatalysis and Oxidation Reactions
T. W. Capehart、R.K. Mishra、C. D. Fuerst 等 6 位作者1997-05-01Physical review. B, Condensed matter
In ${\mathrm{Ce}}_{2}$${\mathrm{Fe}}_{14}$B and ${\mathrm{Ce}}_{2}$${\mathrm{Fe}}_{17}$, cerium is mixed valent and nonmagnetic. Any structural or compositional modification of these intermetallics which induces cerium to become trivalent and develop a local 4f moment should result in compounds with enhanced magnetost…
Magnetic properties of thin filmsRare-earth and actinide compoundsMagnetic Properties of Alloys