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。
The second harmonic generation (SHG) by the femtosecond pulses in a nematic liquid crystal has been experimentally studied. It was found that the SHG by a light beam occurs in the bulk of the liquid crystal sample, is accompanied by a luminescence, and is only observed in the presence of the light-induced director reo…
Abstract Stabilization of electroluminescence (EL) from nanocrystalline porous silicon diodes has been achieved by using high pressure water vapor annealing (HWA) of nanocrystalline porous silicon (PS). HWA is performed at 260 °C and a pressure of 1.3 MPa. Devices treated by HWA show no degradation in EL intensity and…
This is the first part of a two-part paper that describes the experimental observations for two similar sections of floor that were dropped onto both hard and water surfaces at 8 m/s, as a part of one experimental campaign. The current paper provides an assessment of a simple box-beam underfloor structure typically fo…
In this work maximum concentrations of the impurities hydrogen chloride and hydrogen sulfide in synthetic wood gas for operation of a solid oxide fuel cell (SOFC) at different working temperatures and flow conditions are reported. Additionally, an analysis of the influence of the impurity concentrations during the hea…
Thermal residual stresses in SiC matrix – MoSi2 reinforced composites were investigated by Raman microprobe spectroscopy and X-ray diffraction. The introduction of 10 and 30 vol% MoSi2 particles generated compressive stresses in the SiC matrix, with magnitude of about –80 and –190 MPa, respectively. A typical residual…
Abstract This paper deals with On‐Chip‐Electrophoresis separation systems micromachined on porous silicon. The electrical insulation properties of the porous substrates were analyzed and related to physical and chemical treatments such as thermal oxidation and silanisation. From this preliminary study, microfluidic de…
Abstract Summary : In this work, we discuss a simple evolutionary algorithm that introduces a “selection pressure” under which two‐letter (AB) copolymer sequences can mutate and transform into the sequences tuned to microphase separation transition (MIST). In particular, we are interested in determining how a sequence…
This paper presents the results of investigation of impregnating polyester varnish modified by incorporation of various nanoparticles: fumed nanosilica, nanosilica and titanium dioxide obtained via sol-gel process, zinc oxide or montmorillonite at loading 1-3 wt. %. The compositions have been formulated using various…
The application of pulse magnetic field to metal solidification is an advanced technique which can remarkably refine solidification structure. In this paper, the effect of pulse magnetic field on solidification structure, mechanical properties and conductivity of pure copper was experimentally investigated. The result…
The effect of a partial or full replacement of yttrium by ytterbium on the crystallization of an oxynitride B‐phase parent glass with composition (e/o) 35Y/Yb:45Si:20Al:83O:17N has been investigated by thermal analysis, X‐ray diffractometry and analytical transmission electron microscopy. Single B‐phase formation was…
We investigated the desorption process of Au nanoparticles immobilized on an amino-terminated SiO 2 /Si surface in a D 2 O environment by in situ attenuated total reflection surface enhanced infrared absorption spectroscopy. The advantages of IR spectroscopy over other methods were demonstrated; the IR spectra are not…
Several model structures have been generated by molecular dynamics simulations for two precursor‐derived amorphous Si‐C‐N ceramics with stoichiometry Si37C32N31 and Si40C24N36, respectively. These can be considered as possible atomistic model structures for the real amorphous ceramics. Although these models vary in th…
Li 0.5 Fe 2.5 O 4 powders were prepared by high temperature thermal decomposition (HTTD) and sol-gel methods. The sample prepared by HTTD method (SA) has space group of Fd3m. The samples annealed at 700°C (SB) and quenched at 1000°C (SC) prepared by sol-gel method have space groups of P4332 and Fd3m, respectively. The…
Silk is a natural protein fibre. It is the only natural fibre available in continuous filament form. Earlier research studies on physical structure and mechanical properties of silk have indicated that the physical and chemical architecture varies between different varieties of silk and a substantial variation of thes…
Light-emitting diodes (LEDs) have been fabricated in which optically active centers are formed by implantation of erbium ions into silicon and subsequent high-temperature annealing in an oxidizing atmosphere and the p-n junction and the ohmic contact are formed by chemical vapor deposition of polycrystalline silicon l…
A model of the accommodation mechanism of the formation of broken subboundaries has been studied by means of computer simulation. It is established that an increase in the power Ω of a disclination on a grain boundary leads to the activation of a source of dislocations in the grain volume, which results in the formati…
Solid‐state NMR spectroscopy is employed for the structural characterization of precursor‐derived Si‐B‐C‐N ceramics. Particular emphasis is given to the structural composition of the BNCx phase which plays a key role for the unusual high temperature stability of these materials. In the present work 11B{15N} REDOR and…
Structural foam cores are becoming more competitive and promise to make a greater contribution to the success of composite sandwich structures. George Marsh reports.
The crystalline and magnetic structures of YMnO 3 and LuMnO 3 hexagonal manganites under pressures of 0–6 GPa and in the temperature range 10–295 K have been investigated by neutron diffraction. Application of pressure leads to a significant decrease in the ordered magnetic moment of Mn ions (at T = 10 K) from 3.27 (0…
Potassium bis(malonato)borate C6H4BKO8 (I) was synthesized for the first time in an aqueous medium. Well-shaped single crystals were formed. Their X-ray diffraction structure (space group P $$\overline 1 $$ , a = 7.4073(2) Å, b = 7.9161(2) Å, c = 9.0755(2) Å, α 113.225(1)°, β = 91.553(1)°, γ = 104.760(2)°, Z = 2) was…