Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
It is demonstrated theoretically that particle irradiation may lead to a destabilization of graphitic structures with respect to low-pressure growth of diamond. This is due to the large difference in the cross sections for irradiation-induced displacements of carbon atoms in diamond and graphite. A nonequilibrium phas…
Until now, it has been observed that a collective handling of uniform spheres could only lead to a random close packing of 0.64 maximum volume fraction. In this Letter, we show that denser crystalline arrangements can be obtained when beads are poured at low flow rates into a horizontally shaken container. A parallel…
The photoluminescence (PL) and electroluminescence (EL) properties of Ge-implanted SiO2 layers thermally grown on a Si substrate were investigated and compared to those of Si-implanted SiO2 films. The PL spectra from Ge-implanted SiO2 were recorded as a function of annealing temperature. It was found that the blue-vio…
Understanding the thermal conductivity and heat transfer processes in superlattice structures is critical for the development of thermoelectric materials and optoelectronic devices based on quantum structures. This letter reports modeling of the heat transfer and thermal conductivity of superlattice structures based o…
Silicon dioxide films grown by industrial thermal furnace, rapid thermal, and low-pressure thermal methods were measured by x-ray photoelectron spectroscopy, transmission electron microscopy (TEM), spectroscopic ellipsometry, and capacitance–voltage analysis. Based on TEM measurements, the photoelectron effective atte…
The development of the ordered channel array in the anodic porous alumina was initiated by the textured pattern of the surface made by the molding process, and growth of an almost defect-free channel array can be achieved throughout the textured area. The long-range-ordered channel array with dimensions on the order o…
Dynamics of coarsening of a statistically homogeneous fractal cluster, created by a morphological instability of diffusion-controlled growth, is investigated theoretically. An exact mathematical setting of the problem is presented that obeys a global conservation law. A statistical mean field theory is developed that…
We simulate dense diblock copolymer melts using the lattice bond-fluctuation method. Letting the lengths NA and NB of the A- and B-subchains vary (with NA+NB=N) we study the dependence of the static and dynamic properties on f=NA/N. Changes in the A-B interaction parameter allow to mimic large temperature variations.…
Monte Carlo simulations have been performed for a discotic liquid crystal composed of Gay–Berne particles. On the basis of these simulations for the nematic phase, a subset of the spherical harmonic expansion coefficients of the direct pair correlation function (DPCF) were determined from the pair distribution functio…
We carry out extensive molecular dynamics simulations in order to evaluate the thermodynamic equation of state of the extended simple point charge model of water (customarily described by the acronym SPC/E) over a wide range of temperature and density, with emphasis on the supercooled region. We thereby determine the…
The network structure of natural rubber (NR) achieved during vulcanization was analyzed using the model of rubber elasticity based on the tube concept, applied to the treatment of the stress-strain measurements. This theory allows the separation of constraint and crosslink contributions. Also, network parameters can b…
Epoxy-based divinyl ester resins (DVER) were obtained by reacting diglycidyl ether of bisphenol A (DGEBA) with methacrylic acid (MA) and characterized by FTIR and 1H-NMR spectroscopies and gel permeation chromatography (GPC). The densities and viscosities of the DVER in styrene (S) solutions were measured at different…
Thermoplastic elastomeric hydrogenated styrene—butadiene (HSBR) elastomer was prepared by diimide reduction of styrene-butadiene rubber in the latex stage. The products were characterized by infrared, 1H-NMR, 13C-NMR spectroscopy, and differential scanning calorimetry (DSC). The standard free energy change, ΔG0 at 298…
An important aspect of designing polymeric articles for engineering applications and predicting their properties over their lifetime is the computation of their time-dependent viscoelastic behavior. A simplified numerical computational technique based on a Gaussian spectral distribution model was developed to describe…
Adiabatic temperature rise has been recorded as a function of polymerization time to investigate an adiabatic copolymerization kinetics of ϵ-caprolactam (CL) in the presence of several activators, considering different initial copolymerization temperatures ranging from 130 to 160°C. The copolymerization of CL and PEG-…
The imbedded fiber retraction method was used to assess the effect of increasing octene content and comonomer type on the compatibility of polypropylene-polyolefin elastomer (PP-POE) blends via direct measure of the interfacial tension. The interfacial tension was found to decrease monotonically with increasing octene…
Heavy current bushings passing through steel cover plates and housing walls of power transformers, generators and other large power equipment are thermally hazardous elements of construction and a source of additional power losses. The safety and reliability of such expensive objects and the safety of power delivery o…
The crystallization and morphology of reactor-made blends of isotactic polypropylene (PP) with a large content of ethylene-propylene rubber (EPR) (i.e., > 50%) were investigated. In the blends, PP was found to form spherulites during the crystallization process, with the growth rate constant under isothermal condition…
By using 30/70 polyethersulfone/NMP (N-methyl-2-pyrrolidone) solutions as an example, we have determined the role of air-gap distance on nascent fiber morphology, performance, and thermal properties. An increase in air-gap distance results in a hollow fiber with a less layer of fingerlike voids and a significant lower…
Quantitative x-ray diffraction investigations were performed on ultrafine-grained copper samples with various crystallite sizes processed by severe plastic deformation. In the x-ray diffraction patterns, common features such as the relative maximum intensity, considerable broadening, long tails, centroid positions of…