Maria Letizia Focarete、Giuseppina Ceccorulli、Mariastella Scandola 等 4 位作者1998-11-07Macromolecules
Blends of atactic poly[( R, S )-3-hydroxybutyrate], a-PHB, with poly(ε-caprolactone), PCL, and with poly( l -lactic acid), PLLA, were obtained in the form of compression-molded films. The phase behavior of the blends was different: a-PHB and PCL were totally immiscible, whereas a-PHB/PLLA blends were miscible over the…
Microplastics and Plastic PollutionCarbon dioxide utilization in catalysisbiodegradable polymer synthesis and properties
Nelle L. Slack、Mathias Schellhorn、Petra Eiselt 等 9 位作者1998-11-06Macromolecules
We report the first evidence of the potential of new amphiphilic ABA-triblock copolymers as gelling agents for lamellar liquid crystalline L α phases. Recently, we described a new type of lamellar hydrogels which are not based on a polymer network swollen in water but are obtained by the addition of small amounts of a…
Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsLipid Membrane Structure and Behavior
Masatoshi Tokita、Kensuke Osada、Masayuki Yamada 等 4 位作者1998-11-06Macromolecules
Smectic state morphology of the main-chain liquid crystal PB-14 polyester was studied by small-angle X-ray scattering (SAXS), differential scanning calorimetry, and transmission electron microscope methods. The PB-14 polyester forms isotropic liquid (I), smectic H (S H ), and crystalline phases in order of decreasing…
Material Dynamics and PropertiesSurfactants and Colloidal SystemsLiquid Crystal Research Advancements
Naoki Sakamoto、Takeji Hashimoto1998-11-06Macromolecules
We have investigated the ordering dynamics of a triblock copolymer of a polystyrene- block -polyisoprene- block -polystyrene with asymmetric composition from the disordered sphere phase, where spherical microdomains exist but they have only a short-range liquidlike order, to the cylindrical and spherical microdomains…
Rheology and Fluid Dynamics StudiesBlock Copolymer Self-AssemblyPolymer crystallization and properties
Amy Herhold、Deniz Ertas、Alex J. Levine 等 4 位作者1998-11-06arXiv
We report detailed nucleation studies on the liquid-to-solid transition of hexadecane using nearly monodisperse hexadecane-in-water emulsions. A careful consideration of the kinetics of isothermal and nonisothermal freezing show deviations from predictions of classical nucleation theory, if one assumes that the emulsi…
Soft Condensed MatterMaterials Science
Kwok-On Ng、David Vanderbilt1998-11-06arXiv
We present first-principles calculations of the structural and electronic properties of Si(001)-SiO2 interfaces. We first arrive at reasonable structures for the c-Si/a-SiO2 interface via a Monte-Carlo simulated annealing applied to an empirical interatomic potential, and then relax these structures using first-princi…
Materials Science
A. I. Yanson、G. Rubio Bollinger、H. E. van den Brom 等 5 位作者1998-11-06arXiv
The continuing miniaturization of microelectronics raises the prospect of nanometre-scale devices with mechanical and electrical properties that are qualitatively different from those at larger dimensions. The investigation of these properties, and particularly the increasing influence of quantum effects on electron t…
Materials ScienceMesoscale and Nanoscale Physics
Zhen Wang、Thomas J. Pinnavaia1998-11-06OpenAlex
The first examples of thermoset polyurethane−clay nanocomposites have been prepared by curing a polyurethane network in the presence of alkylammonium-exchanged forms of montmorillonite. A unique stress−strain behavior was observed for the elastomeric nanocomposites. The reinforcement effects of the silicate nanolayers…
Polymer Nanocomposites and PropertiesPolymer composites and self-healingConcrete and Cement Materials Research
Zhi Ren、Zhiwei Huang、Jiasai Xu 等 7 位作者1998-11-06OpenAlex
Free-standing aligned carbon nanotubes have previously been grown above 700 degreesC on mesoporous silica embedded with iron nanoparticles. Here, carbon nanotubes aligned over areas up to several square centimeters were grown on nickel-coated glass below 666 degreesC by plasma-enhanced hot filament chemical vapor depo…
Silicon Nanostructures and PhotoluminescenceGraphene research and applicationsCarbon Nanotubes in Composites
Frank Caruso、Rachel A. Caruso、Helmuth Möhwald1998-11-06OpenAlex
Hollow silica and silica-polymer spheres with diameters between 720 and 1000 nanometers were fabricated by consecutively assembling silica nanoparticles and polymer onto colloids and subsequently removing the templated colloid either by calcination or decomposition upon exposure to solvents. Scanning and transmission…
Electrophoretic Deposition in Materials SciencePolymer Surface Interaction StudiesMesoporous Materials and Catalysis
Feng Zhao、Edward E. E. Frietman、Xiao Li1998-11-05Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE
In this paper, a novel type of red sensitive photo-polymer system for optical storage, here called RSPP, is presented. First of all, the components in RSPP, for example, photo- sensitizer, photo-initiator, monomer, copolymer, combiner, stabilizer, hardener, and fabrication and processing technique of RSPP are given. T…
Photonic and Optical DevicesLiquid Crystal Research AdvancementsSemiconductor Lasers and Optical Devices
Dmitry N. Chigrin、Andrei V. Lavrinenko、Dmitry A. Yarotsky 等 4 位作者1998-11-05arXiv
We show that under certain conditions one-dimensional dielectric lattice possesses total omnidirectional reflection of incident light. The predictions are verified experimentally using Na3AlF6/ZnSe multilayer structure developed by means of standard optical technology. The structure was found to exhibit reflection coe…
Materials ScienceSoft Condensed Matter
O.A. Ruano、O.D. Sherby、J. Wadsworth1998-11-04University of North Texas Digital Library (University of North Texas)
A review is presented of the debates between the present authors and other investigators regarding the possible role of diffusional creep in the plastic flow of polycrystalline metals at low stresses. These debates are recorded in eleven papers over the past seventeen years. ln these papers it has been shown that the…
High Temperature Alloys and CreepMaterial Properties and Failure MechanismsMicrostructure and mechanical properties
Takuji Ikeda、Fujio Izumi、Tetsuya Kodaira 等 4 位作者1998-11-04Chemistry of Materials
The electron-density distribution in hydrated and dehydrated sodium-type zeolite LTA was visualized from X-ray powder diffraction data by combining Rietveld analysis and a maximum-entropy method. The X-ray diffraction data were analyzed on the basis of the composition Na 95 Si 97 Al 95 O 384 and a structural model (sp…
Zeolite Catalysis and SynthesisCrystal Structures and PropertiesX-ray Diffraction in Crystallography
Toshiyuki Hibino、Atsumu Tsunashima1998-11-04Chemistry of Materials
Calcined hydrotalcite-like compounds (HTlcs) can be reconstructed to their original structure by exposure to an aqueous solution, provided that the original HTlcs contain volatile interlayer anions. In the present study, repetitive treatment consisting of calcination at 400 °C and subsequent reconstruction in an aqueo…
Magnesium Oxide Properties and ApplicationsLayered Double Hydroxides Synthesis and ApplicationsMicrowave Dielectric Ceramics Synthesis
Richard W. Wagner、Feirong Li、Hai Du 等 4 位作者1998-11-03Organic Process Research & Development
Prior manual work has shown that the condensation of mesitaldehyde and pyrrole leading to tetramesitylporphyrin depends sensitively on concentration and requires cocatalysis involving BF 3 ·O(Et) 2 and ethanol or other protic species. We have applied an automated microscale chemistry workstation capable of parallel or…
Porphyrin and Phthalocyanine ChemistryOxidative Organic Chemistry ReactionsSurface Chemistry and Catalysis
M. A. Novotny、M. Kolesik、P. A. Rikvold1998-11-03arXiv
We provide a proof that when there is no forcing the recently introduced projective dynamics Monte Carlo algorithm gives the exact lifetime of the metastable state, within statistical uncertainties. We also show numerical evidence illustrating that for slow forcing the approach to the zero-forcing limit is rather rapi…
cond-mat.stat-mechMaterials Science
Giorgio Bertotti、Vittorio Basso、Alessandro Magni1998-11-03arXiv
The conditions under which relaxation dynamics in the presence of quenched-in disorder lead to rate-independent hysteresis are discussed. The calculation of average hysteresis branches is reduced to the solution of the level-crossing problem for the stochastic field describing quenched-in disorder. Closed analytical s…
Materials Science
E. Penev、P. Kratzer、M. Scheffler1998-11-03arXiv
Three different clusters, Si_9H_12, Si_15H_16, and Si_21H_20, are used in density-functional theory calculations in conjunction with ab initio pseudopotentials to study how the energetics of H_2 dissociativ e adsorption on and associative desorption from Si(001) depends on the cluster size. The results are compared to…
Materials Science
R. Resta、S. Sorella1998-11-03arXiv
The insulating state of matter is characterized by the excitation spectrum, but also by qualitative features of the electronic ground state. The insulating ground wavefunction in fact: (i) sustains macroscopic polarization, and (ii) is localized. We give a sharp definition of the latter concept, and we show how the tw…
Strongly Correlated ElectronsMaterials Science