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991.
J.H. Kim H.Y. Koo S.K. Hong J.M. Han H.C. Jang Y.N. Ko Y.J. Hong Y.C. Kang S.H. Kang S.B. Cho 《Advanced Powder Technology》2012,23(3):387-392
Fe powders for thermal batteries were prepared by reduction of iron oxide powders obtained by spray pyrolysis. The iron oxide powders prepared by spray pyrolysis had fine size, spherical shape and high surface area. The morphologies of the Fe powders were affected by the preparation temperatures of the iron oxide powders. The Fe powders obtained from the iron oxide powders prepared by spray pyrolysis at 900 and 1000 °C had slightly aggregated structure of the primary powders with several microns sizes. The powders had pure Fe phases at reducing temperatures between 600 and 800 °C. The heat pellets with diameter of 18.2 mm were prepared using Fe powders and potassium perchlorate (KClO4). The porosity of the prepared heat pellet was about 40%. The break strength of the heat pellet was 0.9 kgf. The ignition sensitivity of the heat pellet was 4 W. The maximum burn rate of the heat pellet obtained from the Fe powders were 8.6 cm s?1. 相似文献
992.
993.
Huang WY Yeh CL Lin JH Yang JS Ko TH Lin YH 《Journal of materials science. Materials in medicine》2012,23(6):1465-1478
This work developed a novel bi-layer wound dressing composed of 3D activated carbon fibers that allows facilitates fibroblast cell growth and migration to a wound site for tissue reconstruction, and the gentamicin is incorporated into a poly(γ-glutamic acid)/gelatin membrane to prevent bacterial infection. In an in vitro, field emission scanning electron microscopy shows that rat skin fibroblasts appeared and spread on the surface of activated carbon fibers, and penetrated the interior and exterior of the 3D activated carbon fiber construct to a depth of roughly 200 μm. An in vivo analysis shows that fibroblast cells containing the proposed 3D scaffold had the potential of a biologically functionalized dressing to accelerate wound closure. Additionally, fibroblasts migrated to the wound site in a bi-layer wound dressing containing fibroblasts, enhancing fibronectin and type I collagen expression, resulting in faster skin regeneration than that achieved with a Tegaderm? hydrocolloid dressing or gauze. 相似文献
994.
Rampichová M Martinová L Koštáková E Filová E Míčková A Buzgo M Michálek J Přádný M Nečas A Lukáš D Amler E 《Journal of materials science. Materials in medicine》2012,23(2):555-563
The structural properties of microfiber meshes made from poly(2-hydroxyethyl methacrylate) (PHEMA) were found to significantly
depend on the chemical composition and subsequent cross-linking and nebulization processes. PHEMA microfibres showed promise
as scaffolds for chondrocyte seeding and proliferation. Moreover, the peak liposome adhesion to PHEMA microfiber scaffolds
observed in our study resulted in the development of a simple drug anchoring system. Attached foetal bovine serum-loaded liposomes
significantly improved both chondrocyte adhesion and proliferation. In conclusion, fibrous scaffolds from PHEMA are promising
materials for tissue engineering and, in combination with liposomes, can serve as a simple drug delivery tool. 相似文献
995.
Won HS Kim HG Yun YS Jeon EK Ko YH Kim YS Kim YO Yoon SA 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(1):31-37
Anemia is a common complication in dialysis patients because of their relative erythropoietin deficiency. Despite treatment with erythropoiesis-stimulating agents (ESAs), some patients experienced ESA hyporesponsiveness. We evaluated the clinical and laboratory factors that affect ESA hyporesponsiveness and investigated the relationships between hepcidin, inflammatory markers, and the iron profiles of hemodialysis patients. Sixty-eight patients receiving hemodialysis at a single institution were evaluated in a cross-sectional study. The patients were divided into tertiles based on the ESA hyporesponsiveness index (EHRI), defined as the weekly ESA dose per kilogram of body weight divided by the hemoglobin level. The mean EHRI values for each tertile were 3.3 ± 1.2 (T1), 10.2 ± 2.9 (T2), and 24.5 ± 11.6 (T3). The mean serum erythropoietin levels were significantly higher in the Q3 and Q4 groups. Thus, patients with ESA hyporesponsiveness showed relative resistance to erythropoietin therapy. In univariate and multivariate analyses, patients in the third tertile of EHRI showed significantly higher mean interleukin-6 (IL-6) levels. Serum C-reactive protein (CRP) levels showed a similar trend, but the differences were not significant. Serum hepcidin levels tended toward lower mean values in the third tertile of EHRI. No relationship was observed between hepcidin and inflammatory markers or iron status. In conclusion, IL-6, but not CRP, is a strong predictor of ESA hyporesponsiveness in hemodialysis patients who have sufficient iron. It may be difficult to use hepcidin as an independent clinical marker because of the many factors that influence it and their interactions. 相似文献
996.
We fabricated the vertically-aligned zinc oxide (ZnO)/silicon (Si) double nanostructures by simple processes using the metal-assisted chemical etching and a subsequent hydrothermal synthesis, and their optical property was investigated. For efficient antireflection characteristics, Si nanostructures were optimized by changing the size of the dewetted silver (Ag) at different etching times. The thermally dewetted Ag nanoparticles or semi-island films as metal catalysts were controlled by the Ag film thickness and dewetting temperature. To form the ZnO/Si double nanostructures, ZnO nanorods were synthesized on the chemically etched Si nanostructures using a thin sputtered ZnO seed layer. The grown ZnO nanorod arrays (NRAs) exhibited good crystallinity and further reduced the surface reflection due to their antireflective property. The ZnO/Si double nanostructures showed the increased peak intensity of X-ray diffraction as well as the significantly reduced solar weight reflectance of 6.05% compared to 11.71% in the ZnO NRAs on the flat Si substrate. Also, the enhanced antireflection property of ZnO/Si double nanostructures was theoretically analyzed by performing the rigorous coupled wave analysis simulation. 相似文献
997.
For this investigation of the Ge behavior of condensed Si(1-y)Ge(y) (y > x) cores during the oxidation of Si(1-x)Ge(x) nanowires, Si(1-x)Ge(x) nanowires were grown in a tube furnace by the vapor-liquid-solid method and thermally oxidized. The test results were characterized using several techniques of transmission electron microscopy. The two types of Ge condensation are related to the diameter and Ge content of the nanowires. The consumption of Si atoms in prolonged oxidation caused the condensed SiGe cores to become Ge-only cores; and the continuous oxidation resulted in the oxidation of the Ge cores. The oxidation of Ge atoms was confirmed by scanning transmission electron microscopy. 相似文献
998.
Lee W Yoo B Kim K Lee DK Kim H Ko MJ 《Journal of nanoscience and nanotechnology》2012,12(2):1492-1496
The compact and thin TiO2 blocking layers (c-TiO2) were formed on F-doped SnO2 (FTO) substrate in quantum dots-sensitized solar cells (QSSCs) by chemical deposition. The c-TiO2 layers induced indirect contact between electrolyte and FTO electrode, which reduced leakage in QSSCs. The QSSCs showed power conversion efficiency (Eff) of 3.85% in the presence of c-TiO2 layers which leads to 21% improved compared to that without c-TiO2 layers (Eff = 3.18%). The presence of the c-TiO2 layers in QSSCs also improved the stability under illumination. 相似文献
999.
Electrocatalytic performances of phthalocyanines (Pcs) involving N-benzyl-4-phenyloxyacetamide moieties, dispersed on a high-surface area carbon substrate, Vulcan XC-72 (VC) and Nafion (Nf), towards oxygen reduction in acidic medium were determined and compared. The VC/Nf/CoPc(5) catalyst showed much higher catalytic activity than those of the other Pc(1–4)-based catalysts (H2Pc 1, ZnPc 2, NiPc 3 and CuPc 4) and that of unsubstituted CoPc-based one. The comparison of the performance of VC/Nf/Pt-5 dual catalyst with that of VC/Nf/Pt one indicated that the former can be a good alternative to the latter as a cathode catalyst both in direct methanol and H2/O2 fuel cell applications. 相似文献
1000.
Wentao Zhai Yoorim Ko Wenli Zhu Anson Wong Chul B. Park 《International journal of molecular sciences》2009,10(12):5381-5397
The crystallization and melting behaviors of linear polylactic acid (PLA) treated by compressed CO2 was investigated. The isothermal crystallization test indicated that while PLA exhibited very low crystallization kinetics under atmospheric pressure, CO2 exposure significantly increased PLA’s crystallization rate; a high crystallinity of 16.5% was achieved after CO2 treatment for only 1 min at 100 °C and 6.89 MPa. One melting peak could be found in the DSC curve, and this exhibited a slight dependency on treatment times, temperatures, and pressures. PLA samples tended to foam during the gas release process, and a foaming window as a function of time and temperature was established. Based on the foaming window, crystallinity, and cell morphology, it was found that foaming clearly reduced the needed time for PLA’s crystallization equilibrium. 相似文献