S. Fazekas、J. Kertész、D. E. Wolf2004-04-09arXiv
We performed computer simulations based on a two-dimensional Distinct Element Method to study granular systems of magnetized spherical particles. We measured the angle of repose and the surface roughness of particle piles, and we studied the effect of magnetization on avalanching. We report linear dependence of both a…
Materials ScienceSoft Condensed Matter
H. A. Taroco、A. L. Mota2004-04-09arXiv
In this work we present an application of the lambda-phi^4 field theoretical model to the adsorption of atoms and molecules on metallic surfaces - the electrochemical deposition. The usual approach to this system consists in the computational simulation using Monte Carlo techniques of an effective lattice-gas Hamilton…
Materials Science
A. Aguayo、David J. Singh2004-04-09Physical Review B
Density-functional calculations of the electronic structure of the complex hydride ${\mathrm{NaAlH}}_{4}$ and the reference systems NaH and ${\mathrm{AlH}}_{3}$ are reported. We find a substantially ionic electronic structure for ${\mathrm{NaAlH}}_{4},$ which emphasizes the importance of solid-state effects in this ma…
Quantum, superfluid, helium dynamicsNuclear Materials and PropertiesHydrogen Storage and Materials
S. B. Roy、G. K. Perkins、M. K. Chattopadhyay 等 8 位作者2004-04-09Physical Review Letters
First order ferromagnetic (FM) to antiferromagnetic (AFM) phase transition in doped CeFe2 alloys is studied with the micro-Hall probe technique. Clear visual evidence of magnetic phase coexistence on micrometer scales and the evolution of this phase coexistence as a function of temperature, magnetic field, and time ac…
Magnetic Properties of AlloysMagnetic and transport properties of perovskites and related materialsRare-earth and actinide compounds
Orlando Auciello、J. Birrell、John A. Carlisle 等 7 位作者2004-04-09Journal of Physics Condensed Matter
Most MEMS devices are currently based on silicon because of the available surface machining technology. However, Si has poor mechanical and tribological properties which makes it difficult to produce high performance Si based MEMS devices that could work reliably, particularly in harsh environments; diamond, as a supe…
Diamond and Carbon-based Materials ResearchMetal and Thin Film MechanicsForce Microscopy Techniques and Applications
Yurii A. Shchipunov、Tat'yana Yu. Karpenko2004-04-09Langmuir
New monolithic nanocomposite silica biomaterials were synthesized on the basis of various natural polysaccharides and recently introduced completely water-soluble precursor tetrakis(2-hydroxyethyl) orthosilicate. The sol-gel processes were performed in aqueous solutions without the addition of organic solvents and cat…
Diatoms and Algae ResearchBone Tissue Engineering MaterialsMesoporous Materials and Catalysis
Dale R. Miller、Dale C. Swenson、Edward G. Gillan2004-04-09Journal of the American Chemical Society
Derivatized s-triazine (C3N3) precursors have seen significant recent use in the production of carbon nitride materials. Larger polycyclic molecular precursors, such as those containing an s-heptazine core (C6N7 or tri-s-triazine), may improve stability and order in carbon nitride products. In this Communication, we d…
Synthesis and Characterization of Heterocyclic CompoundsOrganic Light-Emitting Diodes ResearchLuminescence and Fluorescent Materials
Dmitry Zaslavsky、Andrei Pakoulev、Vladimir Burtman2004-04-09arXiv
The interest in monomolecular films as electric conductors arises from the search for innovative materials. The utility of non-covalently bonded films is limited because they are mechanically unstable and consist of poorly connected domains. Consequently, charge transfers in these films are limited to the distances in…
cond-mat.otherMaterials Science
Wilfried Wunderlich、Nguyen Thi Hue、Sakae Tanemura2004-04-09arXiv
This research for Eco-materials focuses on the improvement of photo response of titania thin films. The goal of this research is to find a suitable substrate for decreasing the band-gap of titania, to improve the microstructure and to seek for new processing techniques in nano-meter scale. The sol-gel technique using…
Materials Science
Dennis P. Clougherty、Charles A. Foell2004-04-09arXiv
We consider a one dimensional model of an electron in a doubly (or nearly) degenerate band that interacts with elastic distortions. We show that the electron equations of motion reduce to a set of coupled non-linear Schrodinger equations. For the case of interband electron-phonon coupling stemming from local Jahn-Tell…
quant-phMaterials Sciencenlin.PS
Wilfried Wunderlich、Lei Miao、Masaki Tanemura 等 9 位作者2004-04-09arXiv
Titanium dioxide has been extensively studied in recent decades for its important photocatalytic application in environmental purification. The search for a method to narrow the optical band-gap of TiO2 plays a key role for enhancing its photocatalytic application. The optical band gap of epitaxial rutile and anatase…
Materials Science
Ph. Sciau、A. Kania、Brahim Dkhil 等 5 位作者2004-04-09Journal of Physics Condensed Matter
The structures and phase transitions of AgNbO 3 were investigated using neutron powder diffraction and restricted single-crystal x-ray diffraction. Both methods have revealed the high temperature M 3 –O 1 , O 2 –T and T–C phase transitions but have not given any significant evidence of low temperature M 1 –M 2 and M 2…
Ferroelectric and Piezoelectric MaterialsSolid-state spectroscopy and crystallographyMicrowave Dielectric Ceramics Synthesis
Bharat R. Acharya、Andrew N. Primak、Satyendra Kumar2004-04-09OpenAlex
A biaxial nematic phase had been predicted with D(2h) symmetry, wherein the mesogen's long and short transverse axes are simultaneously aligned along the two orthogonal, primary and secondary directors, n and m, respectively. The unique low-angle x-ray diffraction patterns in the nematic phases exhibited by three rigi…
Liquid Crystal Research AdvancementsMolecular spectroscopy and chiralitySynthesis and Properties of Aromatic Compounds
Louis A. Madsen、Theo J. Dingemans、Michi Nakata 等 4 位作者2004-04-09OpenAlex
We have synthesized liquid crystal (LC) mesogens based on a nonlinear oxadiazole unit that exhibit nematic phases near 200 degrees C. Polarized microscopy and conoscopy indicate that these LCs are biaxial nematics. Unambiguous and quantitative evidence for biaxiality is achieved using 2H NMR spectroscopy. "2D powder"…
Liquid Crystal Research AdvancementsPlant Reproductive BiologyPhotonic Crystals and Applications
Hongyi Zhou2004-04-08Journal of Applied Polymer Science
Abstract Efforts to evaluate interlayer adhesion of coextruded films are often hampered by the inability to initiate delamination. On the other hand, interlayer delamination was often noticed at cut or trimmed edges of coextruded films. In this study, a test method was developed by first initiating delamination by uni…
Polymer crystallization and propertiesMaterial Properties and ProcessingMechanical Behavior of Composites
Kun Xu、John C. Selby、Mark A. Shannon 等 4 位作者2004-04-08Journal of Applied Polymer Science
Abstract The adhesion mechanism between polyimides and aromatic thermosetting copolyester (ATSP) involved in the solid‐state bonding technique using submicrometer ATSP coatings was evaluated. The adhesion strength at the interface between ATSP and polyimide is strongly related to the diffusion of ATSP into the polyimi…
Organic Electronics and PhotovoltaicsSynthesis and properties of polymersSilicone and Siloxane Chemistry
Marta Castellote、Esperanza Menéndez、Carmen Andrade 等 6 位作者2004-04-08Environmental Science & Technology
Electric arc furnace dust (EAFD), generated by the steel-making industry, is in itself an intrinsic hazardous waste; however, the case may also be that scrap used in the process is accidentally contaminated by radioactive elements such as cesium. In this case the resulting EAFD is to be handled as radioactive waste, b…
Graphite, nuclear technology, radiation studiesNon-Destructive Testing TechniquesNuclear and radioactivity studies
Guoping Yan、Hua Li、Si‐Xue Cheng 等 7 位作者2004-04-08Journal of Applied Polymer Science
Abstract A series of biodegradable amphiphilic A‐B‐A type triblock copolymers P(BLA‐PEG‐BLA), composed of hydrophilic poly(ethylene glycol) (PEG) as a middle block component (B) and hydrophobic poly(β‐benzyl‐ L ‐aspartate) as outer polypeptide block components (A), were synthesized by copolymerization of β‐benzyl‐ L ‐…
Drug Solubulity and Delivery SystemsAdvanced Drug Delivery SystemsNanoparticle-Based Drug Delivery
Noriaki Kubota、S. Sasaki、Norihito Doki 等 5 位作者2004-04-08Crystal Growth & Design
The growth-starting supercooling Δ T G, defined as a supercooling at which a crystal starts to grow on cooling, was measured for the (100) face of a potassium dihydrogen phosphate (KDP) crystal on which an Al (III) impurity had been adsorbed beforehand. When adsorption was made onto the nongrowing (100) face at a low…
Calcium Carbonate Crystallization and InhibitionNonlinear Optical Materials ResearchCrystallization and Solubility Studies
Taesung Jung、Woo‐Sik Kim、Chang Kyun Choi2004-04-08Crystal Growth & Design
The effect of stoichiometric reaction conditions on CaCO 3 crystallization was investigated using a Ca(OH) 2 −H 2 CO 3 reaction system in which the influence of ionic byproducts on the crystallization was effectively excluded. The largest rhombohedron-like crystals were produced under stoichiometic reaction conditions…
Calcium Carbonate Crystallization and InhibitionCrystallization and Solubility StudiesMinerals Flotation and Separation Techniques