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[en] We study the non-uniform nuclear matter using the self-consistent Thomas-Fermi approximation with a relativistic mean-field model. The non-uniform matter is assumed to be composed of a lattice of heavy nuclei surrounded by dripped nucleons. At each temperature T, proton fraction Yp , and baryon mass density ρ B, we determine the thermodynamically favored state by minimizing the free energy with respect to the radius of the Wigner-Seitz cell, while the nucleon distribution in the cell can be determined self-consistently in the Thomas-Fermi approximation. A detailed comparison is made between the present results and previous calculations in the Thomas-Fermi approximation with a parameterized nucleon distribution that has been adopted in the widely used Shen equation of state.
[en] The problem of energy harvesting using piezoelectric transducers for pavement system applications is formulated with a focus on moving vehicle excitations. The pavement behavior is described by an infinite Bernoulli–Euler beam subjected to a moving line load and resting on a Winkler foundation. A closed-form dynamic response of the pavement is determined by a Fourier transform and the residue theorem. The voltage and power outputs of the piezoelectric harvester embedded in the pavements are then obtained by the direct piezoelectric effect. A comprehensive parametric study is conducted to show the effect of damping, the Winkler modulus, and the velocity of moving vehicles on the voltage and power output of the piezoelectric harvester. It is found that the output increases sharply when the velocity of the vehicle is close to the so-called critical velocity. (paper)
[en] Three-dimensional collagen-chitosan scaffolds were fabricated with type I collagen and chitosan through freeze drying and glutaraldehyde cross-linking. Dermal fibroblasts were isolated from neonatal Sprague-Dawley rat skin by dispase II/collagenase I digestion. The fibroblasts were then seeded into the scaffolds to construct tissue-engineered dermis. The microstructure of the scaffolds as well as the fibroblasts' proliferation, cytokine secretion and cell cycle were investigated. Flow cytometry analysis indicated that cells in the scaffolds proliferated steadily. IL-6 concentration measurement by the ELISA test suggested that the scaffolds could promote secretion of the fibroblasts' cytokine. These results show that the fibroblasts and the scaffolds interact well with each other, and the fibroblasts have better proliferation ability and biological activity in the scaffolds than in monolayer culture. The scaffolds are a promising candidate for tissue repair and regeneration with enhanced biostability and good cytocompatibility.
[en] Effect of high magnetic field strength on M6C carbide precipitation morphology in W6Mo5Cr4V3 high speed steel was investigated. Results showed that at low and medium tempering temperatures, the high magnetic field significantly affects the precipitation morphology of M6C carbides and shows strong spheroidization. This effect increases with the enhancement of the magnetic field strength. At high tempering temperature, the high magnetic field has no obvious effect on M6C carbide precipitation behavior. (paper)
[en] TiO2 nanoparticles doped with total 5 mol% of phosphorus and zinc elements were synthesized using a sol-gel method. The alcoholic solution of tetraethylorthotitanite was mixed with an aqueous solution of Zn(NO3)2 and/or H3PO4, followed by refluxing at 90 deg. C for 4 h. After centrifugally filtration and drying, the dried particles were calcined at various temperatures and were then physically and chemically analyzed. The results indicated that by doping both zinc and phosphorus elements into Ti-O framework, the resultant TiO2 can maintain anatase monophase at temperatures as high as 800 deg. C. The P/Zn-TiO2 nanoparticles prepared, using [H3PO4]/[Zn(NO3)2] ≥ 2, at 600-800 deg. C can decompose ≥96 mol% of the MB after 30 min of UV irradiation and ≥80 mol% of the MB after 60 min of white light irradiation, which are much better than those of the P25 particles
[en] The development and application of second generation high temperature superconducting (2G-HTS) tapes have attracted much attention in China recently. Progress in upscaling high performance 2G-HTS tape production at Shanghai Superconductor Technology (SST) is reported in this paper. With ion beam assisted deposition, biaxially textured buffer layers with a configuration of CeO2/LaMnO3/MgO/Y2O3/Al2O3/C-276 have successfully been fabricated. In-plane and out-of-plane texture degrees of CeO2 films achieve 2°–4° and 2°, respectively. A multi-plume multi-turn pulsed laser deposition (PLD) system combined with the so-called ‘radiation assisted conductive heater’ has been proposed and further developed for REBCO layer deposition. Our effort was focused on minimizing the temperature variations in the deposition region by modifying the heating shield that assists the conductive heater of the drum-like cylinder. A tape travelling speed of 100–180 m h−1 can be achieved with a steady temperature profile when passing through the deposition zone, which is very beneficial for the growth of the REBCO layer. Taking advantage of the liquid phase growth mode, several compositions of superconducting films with a thickness in the range of 1–2.5 μm have been grown with high growth rates of over 40 nm s−1. Furthermore, the microstructures and superconducting performance were investigated in detail. Based on these studies, superconducting tapes with piece lengths of up to 500 meters have been developed. High I c values at 77 K, self-field (over 520 A cm−1 width) or at low temperature, high magnetic field conditions (over 560 A/4 mm width at 4.2 K, 10 T, perpendicular field) have been achieved. Lamination and jointing techniques have also been developed by SST for power and magnet applications. (paper)
[en] Copper-indium nanorod arrays have been synthesized by electrodeposition using porous anodic alumina nano template supported on a silicon substrate. Porous anodic alumina template was fabricated by evaporating aluminium film onto silicon substrate and then anodizing the aluminium film in diluted phosphoric acid. The approach employs a plasma etching to penetrate the alumina pore barrier layer before electrodeposition, which enables direct electrical and chemical contact with the silicon substrate electrode. The resulting template and copper-indium nonorods obtained were characterized using scanning electron microscopy (SEM) and energy-dispersived X-ray spectroscopic analyzer (EDS), the pores of alumina are found to have dimensions of 150-250 nm pore diameters and 330-510 nm pore spacings, partial filling of the pores of the alumina template by Cu-In is achieved. The results of this work reveal that the alumina nano template is particularly well suited to the etching mask and template-assisted growth of nanostructures to be integrated into rigid substrate.
[en] This survey was conducted to examine the extent of the exposure of Bangkok citizens to lead (Pb) and cadmium (Cd), and to evaluate the role of rice as the source of these heavy metals. In practice, 52 non-smoking adult women in an institution in the vicinity of Bangkok, volunteered to offer blood, spot urine, boiled rice and 24-h total food duplicate samples. Samples were wet-ashed, and then analyzed for Pb and Cd by ICP-MS. Geometric means for the levels in blood (Pb-B and Cd-B) and urine (Pb-U and Cd-U as corrected for creatinine concentration), and also for dietary intake (Pb-F and Cd-F) were 32.3 μg/l for Pb-B, 0.41 μg/l for Cd-B, 2.06 μg/g creatinine for Pb-U, 1.40 μg/g creatinine for Cd-U, 15.1 μg/day for Pb-F and 7.1 μg/day for Cd-F. Rice contributed 30% and 4% of dietary Cd and Pb burden, respectively. When compared with the counterpart values obtained in four neighboring cities in southeast Asia (i.e. Nanning, Tainan, Manila, and Kuala Lumpur), dietary Pb burden of the women in Bangkok was middle in the order among the values for the five cities. Pb level in the blood was the lowest of the levels among the five cities and Pb in urine was also among the low group. This apparent discrepancy in the order between Pb-B (i.e. the fifth) and Pb-F (the third) might be attributable to recent reduction of Pb levels in the atmosphere in Bangkok. Regarding Cd exposure, Cd levels in blood and urine as well as dietary Cd burden of Bangkok women were either the lowest or the next lowest among those in the five cities. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)
[en] In this work, unsealed short Bi-2223/Ag tapes were treated at the high pressure of 100 bar and at different temperatures. It was found that the tapes which had undergone a pre-treatment at high temperature at normal pressure before they were subjected to high pressure processing (HPP) could be compressed by pressure. The thicknesses of these tapes could be reduced from about 0.230 to about 0.220 mm, and most of the pores and cracks in the cores disappeared. These results might provide a feasible method for manufacturing Bi-2223/Ag tapes by HPP on a large scale
[en] The Taiwanese-American Occultation Survey project is designed for the detection of stellar occultations by small-size Kuiper Belt Objects, and it has monitored selected fields along the ecliptic plane by using four telescopes with a 3 deg2 field of view on the sky since 2005. We have analyzed data accumulated during 2005-2012 to detect variable stars. Sixteen fields with observations of more than 100 epochs were examined. We recovered 85 variables among a total of 158 known variable stars in these 16 fields. Most of the unrecovered variables are located in the fields observed less frequently. We also detected 58 variable stars which are not listed in the International Variable Star Index of the American Association of Variable Star Observers. These variable stars are classified as 3 RR Lyrae, 4 Cepheid, 1 δ Scuti, 5 Mira, 15 semi-regular, and 27 eclipsing binaries based on the periodicity and the profile of the light curves.