Ian M. Reaney、Enrico Colla、N. Setter1994-07-01OpenAlex
The temperature coefficient of the dielectric permittivity (τ ε ) of nonferroelectric complex perovskites is of importance in the application of these cermaics to microwave filters and resonators. Recent work has directly related changes in the τ ε of complex perovskites to the onset of structural phase transitions wh…
Ferroelectric and Piezoelectric MaterialsAcoustic Wave Resonator TechnologiesMicrowave Dielectric Ceramics Synthesis
Damian A. Hajduk、Paul E. Harper、Sol M. Grüner 等 7 位作者1994-07-01OpenAlex
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Gyroid: A New Equilibrium Morphology in Weakly Segregated Diblock CopolymersDamian A. Hajduk, Paul E. Harper, Sol M. Gruner, Christian C. Honeker, Gia Kim, Edwin L. Thomas, and Lewis J. FettersCite this: Macromolecules 1994, 27, 15, 4063–4075Publication Date (Print):July…
Block Copolymer Self-Assembly
Richard A. Vaia、Rachel K. Teukolsky、Emmanuel P. Giannelis1994-07-01OpenAlex
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInterlayer Structure and Molecular Environment of Alkylammonium Layered SilicatesRichard A. Vaia, Rachel K. Teukolsky, and Emmanuel P. GiannelisCite this: Chem. Mater. 1994, 6, 7, 1017–1022Publication Date (Print):July 1, 1994Publication History Published online1 May 2002Pub…
Clay minerals and soil interactionsZeolite Catalysis and SynthesisMesoporous Materials and Catalysis
Fan Yuan、Michael Leunig、S.K. Huang 等 6 位作者1994-07-01OpenAlex
Microvascular permeability and interstitial penetration of sterically stabilized liposomes in both normal s.c. tissue and human colon adenocarcinoma LS174T xenograft were quantified by using the dorsal skin-fold chamber implanted in severe combined immunodeficient mice and intravital fluorescence microscopy. Significa…
Nanoparticle-Based Drug DeliveryNanoplatforms for cancer theranosticsCancer, Hypoxia, and Metabolism
Joseph L. Keddie、Richard Jones、Rachel A. Cory1994-07-01OpenAlex
The glass transition temperature of thin polystyrene films has been measured as a function of film thickness. It is found that the glass transition decreases in temperature as the thickness of the film is reduced. The effect is not strongly molecular-weight dependent, ruling out chain confinement as the major cause; i…
Material Dynamics and PropertiesPhase Equilibria and ThermodynamicsFluid Dynamics and Thin Films
Raffaele Resta1994-07-01OpenAlex
The macroscopic electric polarization of a crystal is often defined as the dipole of a unit cell. In fact, such a dipole moment is ill defined, and the above definition is incorrect. Looking more closely, the quantity generally measured is differential polarization, defined with respect to a "reference state" of the s…
Acoustic Wave Resonator TechnologiesSolid-state spectroscopy and crystallographyPhotorefractive and Nonlinear Optics
Adriano Zanier、Urs Debrunner、Hans W. Jäckle1994-06-29CHIMIA International Journal for Chemistry
Thermoanalytical techniques have found widespread use as a quality-control tool for petroleum and related products. Pressure differential scanning calorimetry (PDSC) has been effectively used as an alternative method to estimate thermal-oxidation stability of middle-destillate fuels. In this paper, the fuels were rate…
Chemical and Physical Properties in Aqueous SolutionsChemical Thermodynamics and Molecular StructureThermal and Kinetic Analysis
Claude Piguet、Bernard Bocquet、Gérard Hopfgartner1994-06-29Helvetica Chimica Acta
Abstract The development of a modified Phillips reaction allows the synthesis of complicated heteroleptic ligands based on pyridine and 1 H ‐benzimidazole moieties. The key‐step formation of aromatic 1 H ‐benzimidazole rings from N ‐(2‐nitroaryl)arenecarboxamides significantly improves the possibilities of the classic…
Magnetism in coordination complexesLanthanide and Transition Metal ComplexesSupramolecular Chemistry and Complexes
F. C. Porter1994-06-29OpenAlex
A cornerstone reference in the field, this work analyzes available information on the corrosion resistance of zinc and its alloys both as solid materials and as coatings on steel, detailing the corrosion resistance of zinc in atmospheric, aqueous, underground and chemical environments. Corrosion Resistance of Zinc and…
Metallurgy and Material Science
Ken C. Usher、S. James Remington、David P. Martin 等 4 位作者1994-06-28Biochemistry
Two extremely potent inhibitors of citrate synthase, carboxyl and primary amide analogues of acetyl coenzyme A, have been synthesized. The ternary complexes of these inhibitors with oxaloacetate and citrate synthase have been crystallized and their structures analyzed at 1.70- and 1.65-A resolution, respectively. The…
Enzyme Structure and FunctionBiochemical and Molecular ResearchCarbohydrate Chemistry and Synthesis
R J Gulley、D T Alle、Michael J. Brennan 等 5 位作者1994-06-28Journal of Physics B Atomic Molecular and Optical Physics
Absolute differential (in angle) and total scattering cross sections for low-energy (0.1-7.0 eV) electron scattering from neon have been measured. Both data sets have been analysed using phaseshift techniques and comparisons are made between the present cross sections and phaseshifts and similar data from previous swa…
Atomic and Molecular PhysicsX-ray Spectroscopy and Fluorescence AnalysisElectron and X-Ray Spectroscopy Techniques
M. Venugopal、John A. M. Ramshaw、Emory H. Braswell 等 5 位作者1994-06-28Biochemistry
Collagen-like peptides with potential for ion pair formation were studied to investigate the role of electrostatic interactions in the triple-helix conformation. Three peptides--(POG)10, the EK-containing peptide (POG)4EKG(POG)5, and T3-487, a peptide with 18 residues of type III collagen and a C-terminal (GPO)4 tail-…
Collagen: Extraction and CharacterizationChemical Synthesis and AnalysisProtein Hydrolysis and Bioactive Peptides
L. Karásek、Bohumil Meissner1994-06-27Journal of Applied Polymer Science
Abstract Experimental data were obtained on the concentration dependence of the fraction of total filler–bound polymer, fraction of polymer in a coherent polymer–filler gel, and fraction of solvent‐dispersed filler particles in compounds of fume silica (Aerosil OX50) with natural rubber (NR) and styrene butadiene rubb…
Adsorption, diffusion, and thermodynamic properties of materialsPolymer Nanocomposites and PropertiesSurfactants and Colloidal Systems
P. H. Hao、X. Y. Hou、F. L. Zhang 等 4 位作者1994-06-27Applied Physics Letters
The energy band gap of light-emitting porous silicon is determined by high-resolution electron energy loss spectroscopy, and the valence band edge of porous silicon with respect to its Fermi level is measured by ultraviolet photoelectron spectroscopy. By combining the results with that measured from clean Si, a pictur…
Silicon Nanostructures and PhotoluminescenceNanowire Synthesis and ApplicationsSemiconductor materials and devices
M.F. Planche、J.C. Thiéblemont、N. Mazars 等 4 位作者1994-06-27Journal of Applied Polymer Science
Abstract The chemical synthesis of polypyrrole in water, with FeCl 3 as an oxidant of pyrrole, was investigated. During these experiments in ambient air, a large evaporation of pyrrole was observed. Moreover, a kinetic study of pyrrole disappearance by high‐performance liquid chromatography (HPLC), with various FeCl 3…
Electrochemical Analysis and ApplicationsAnalytical Chemistry and SensorsConducting polymers and applications
P. Czarnecki、W. Nawrocik、Z. Pająk 等 4 位作者1994-06-27Journal of Physics Condensed Matter
Polycrystalline pyridinium perchlorate has been studied over a wide range of temperatures by differential thermal analysis, proton NMR spectra and relaxation, and dielectric permittivity measurements. Two solid-solid phase transitions at 232 and 248 K have been revealed and the pyridinium cation reorientations in all…
Nonlinear Optical Materials ResearchAcoustic Wave Resonator TechnologiesSolid-state spectroscopy and crystallography
Din Ping Tsai、J. Kovacs、Zhouhang Wang 等 7 位作者1994-06-27Physical Review Letters
Highly localized, laser-excited optical modes of silver colloid fractal clusters were observed using photon scanning tunneling microscopy. The spatial distribution of the modes shows the frequency and polarization selectivity suggested by numerical simulations. The results verify the main concepts of the recently deve…
Photonic Crystals and ApplicationsGold and Silver Nanoparticles Synthesis and ApplicationsNear-Field Optical Microscopy
M. Grae Worster、Ross C. Kerr1994-06-25Journal of Fluid Mechanics
We investigate interactions between interfacial disequilibrium and compositional convection during the freezing of an alloy from below to form a mushy layer. A theoretical model is developed in which a stagnant mushy layer underlies a melt that is convecting vigorously, driven by compositional gradients associated wit…
Solidification and crystal growth phenomenaAluminum Alloy Microstructure PropertiesMetallurgical Processes and Thermodynamics
Stefan H. J. Idziak、Cyrus R. Safinya、Robert Hill 等 9 位作者1994-06-24Science
An x-ray surface forces apparatus for simultaneously measuring forces and structures of confined complex fluids under static and flow conditions is described. This apparatus, combined with an intense synchrotron x-ray source, allows investigation of molecular orientations within a thin liquid crystal film confined bet…
Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsBlock Copolymer Self-Assembly
Joachim Scholz、A. Scholz、Roman Weimann 等 5 位作者1994-06-22Angewandte Chemie International Edition in English
The quinoxaline and phenazine dianions can each be stabilized by two lanthanocene units, which leads to the novel binuclear rare-earth complexes with short LaC and LaN contacts. These La–ligand contacts resemble those in “aromatic alkali-metal amides”. The phenazine complex is shown on the right.
Lanthanide and Transition Metal ComplexesOrganometallic Complex Synthesis and CatalysisMagnetism in coordination complexes