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71.
X-ray photoelectron spectra of Fe 2p32 electrons are measured for passive films on iron and FeCr alloys passivated for 1 h in 1M H2SO4 at + 100 and + 500 mV (s.c.e.). When chromium content of FeCr alloys increased to ca. 12 at.%, binding energy of Fe 2p32 electrons from oxidized state shifted abruptly from ca. 710·3 to ca. 709·6 eV and no more change in binding energy was observed at high chromium content. This abrupt shift of binding energy is in accord with the fact that the Fe2+/Fe3+ ratio showed sharp increase at ca. 12 at.% chromium. This phenomenon can be attributed to the inhibition of oxidation of iron due to the change in film structure and properties.  相似文献   
72.
Guaiacol novolak (GCN) and wood‐tar creosote novolak (WCN) were synthesized by the reactions of wood‐derived guaiacol and creosote with formalin, respectively, and used as hardeners of sorbitol polyglycidyl ether (SPE). Thermal and mechanical properties of the cured resins (SPE‐GCN and SPE‐WCN) and their biocomposites with wood flour (WF) were compared with those of the materials prepared by using a petroleum‐based phenol novolak (PN). Although tan δ peak temperatures of SPE‐GCN and SPE‐WCN were lower than that of SPE‐PN, that (58.5–70.8°C) of SPE‐GCN/WF(40–50 wt %) was higher than that (56.6–57.0°C) of SPE‐PN/WF(40–50 wt %). Tensile moduli of all the biocomposites increased by the addition of WF, while tensile strengths were rather reduced. When the biocomposites with the same WF content were compared, tensile modulus of SPE‐GCN/WF was higher than that of SPE‐PN/WF. The 5% weight loss temperatures (346–291°C) of SPE‐GCN and SPE‐GCN/WF were comparable to those (338–284°C) of SPE‐PN and SPE‐PN/WF. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41347.  相似文献   
73.
Identification of small-molecule ligands for a protein of interest can facilitate the analysis of the protein's functions in biological systems. Small-molecule microarrays have allowed for rapid detection of such ligand-protein interactions in a high-throughput manner, although a label on a protein is needed to observe these interactions. By combining SPR imaging technology with our recently developed photo-cross-linked small-molecule array platform, we developed a novel platform that allows in situ observation of interactions between photo-cross-linked small molecules on gold surfaces and nonlabeled proteins in solution. Interactions of estrogenic and androgenic substances with estrogen receptor alpha were observed using this platform.  相似文献   
74.
Natural convective flows over upward‐facing, inclined plates were investigated experimentally, with an emphasis on the role of opposing flows that appear over the plates inclined slightly from the horizontal line. The flow fields over the plates and the surface temperatures of the heated plates were visualized with both dye and a liquid‐crystal thermometry. The results showed that both the descending and ascending flows appeared over the plates when the inclination angles of the plates were less than 15°. The two flows collided with each other at a certain distance from the plate edge, and then detached from the plate to become a thermal plume. It was found that the above distance was determined solely by the inclination angles and was independent of sizes and heat fluxes of the plates. The local heat transfer coefficients of the plates were also measured. The results showed that the heat transfer from the plate was enhanced by the occurrence of the descending flows. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(5): 362–375, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10036  相似文献   
75.
The presence of radionuclides at five water purification plants was investigated after an explosion at a nuclear power plant hit by the Great East Japan Earthquake on 11 March 2011. Radioactive iodine (131I) and cesium (134Cs and 137Cs) were detected in raw water in Fukushima and neighboring prefectures. 131I was not removed by coagulation-flocculation-sedimentation. 131I was removed by granular activated carbon (GAC) and powdered activated carbon (PAC) at a level of about 30%-40%, although 131I was not removed in some cases. This was also confirmed by laboratory-scale experiments using PAC. The removal percentages of 131I in river and pond waters by 25 mg dry/L of PAC increased from 36% to 59% and from 41% to 48%, respectively, with chlorine dosing before PAC. 134Cs and 137Cs were effectively removed by coagulation at both a water purification plant and in laboratory-scale experiments when turbidity was relatively high. In contrast, 134Cs and 137Cs in pond water with low turbidity were not removed by coagulation. This was because 134Cs and 137Cs in river water were present mainly in particulate form, while in pond water they were present mainly as cesium ions (134Cs+ and 137Cs+). However, the removal of 134Cs and 137Cs in pond water by coagulation increased markedly when 134Cs and 137Cs were mixed with sediment 24 h before coagulation.  相似文献   
76.
The aim of this study is to characterize the damping properties of carbon fiber-reinforced interleaved epoxy composites. Several types of thermoplastic-elastomer films, such as polyurethane elastomers, polyethylene-based ionomers and polyamide elastomers were used as the interleaving materials. The damping properties of the composite laminates with/without the interleaf films were evaluated by the mechanical impedance method. Also, the effects of the lay-up arrangements of the carbon-fiber prepregs on the damping properties of the interleaved laminates were examined. The viscoelastic properties of interleaved polymer films were reflected in the damping properties of the corresponding interleaved laminates. The loss tangent of the interleaf films at the test temperature played an important roll in the loss factor of the interleaved laminates. Also, the stiffness of the films at the resonant frequency of the laminates was another important parameter that controlled the loss factor of the interleaved laminates.  相似文献   
77.
1. A novel ACAT (acyl-CoA: cholesterol acyltransferase) inhibitor, HL-004, exhibited a strong inhibitory effect on the hepatic and intestinal ACAT, but was less effective on the adrenal ACAT in vitro. 2. HL-004 selectively decreased serum VLDL cholesterol, and inhibited hepatic ACAT activity in hamsters fed normal chow. 3. These results suggest that the cholesterol-lowering effect of HL-004 can be attributed to a decrease in hepatic VLDL secretion via inhibition of ACAT.  相似文献   
78.
79.
Turbulent transition mechanism and local heat transfer characteristics of the natural convective flows over upward‐facing inclined plates were investigated experimentally. The experiments were performed in the range of modified local Rayleigh numbers from 104 to 8 × 1014 and of inclination angles θ from 0 to 90°. The flow fields over the plate and the surface temperatures of the plate were visualized with dye and liquid crystal thermometry. The results showed that longitudinal vortices play a main role in the turbulent transition over the plate of θ < 72°. These vortices appear first in the laminar boundary layer, then detach from the plate and, finally become distorted. It is found that the heat transfer is enhanced markedly by the detachment and the distortion of these vortices. The local heat transfer coefficients were measured in the laminar, transitional, and turbulent regions. The results show that the coefficients in the turbulent region become identical and independent of inclination angles. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(3): 278–291, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10091  相似文献   
80.
T. Asami  M. Tanaka  Y. Yanagisawa 《低温学》1996,36(12):997-1003
Characteristics of two types of argon separation process from the purge gas are described, one with two single columns and the other with one double column. Typical flow sheets of these of processes are presented. A comparison is also made for energy consumption in these processes.  相似文献   
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