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151.
Using a direct observation experimental method, the oxide formation behavior on the surface of Fe-Cr-5 mass pct C-Si alloy baths during decarburization by a top-blown Ar-O2 mixture was studied. The effects of the initial Si and Cr content of the alloy, temperature, and oxygen feed ratio on oxide formation were investigated. The results showed that, for alloys without Si, oxide particles, unstable oxide films, and stable oxide films formed sequentially. The presence of Si in the alloy changed the formation behavior of stable oxide film, and increased the crucial C content when stable oxide film started to form. Increasing the temperature, decreasing the initial Cr content, and increasing the ratio of the diluting gas decreased the critical C content at which a stable oxide film started to form. In addition, the P CO and \( a_{{{\text{Cr}}_{2} {\text{O}}_{3} }} \) values at which oxides started to form were estimated using Hilty’s equation and the equilibrium relation to understand the formation conditions and the role of each parameter in oxide formation.  相似文献   
152.
该文针对摄入醋酸菌对于酒精性肝损伤的影响进行了评价。将C57BL/6J小鼠(8周龄,雄性,22~27 g)分为对照组(非乙醇给药组)、乙醇组(给予2.5 g/kg乙醇)、乙醇+醋酸菌组(给予2.5 g/kg乙醇+10 mg醋酸菌),分别每天给药3次,连续经口给药14 d,测定了血清谷草转氨酶(AST)、谷丙转氨酶(ALT)及肝脏油脂浓度。结果表明,与对照组相比较,乙醇组小鼠的AST与ALT浓度,肝脏甘油三酯与胆固醇浓度显著增高(P<0.05);乙醇+醋酸菌组的数值则显著低于乙醇组(P<0.05)。以上结果表明,摄入醋酸菌有可能会减轻酒精性肝损伤。  相似文献   
153.
The interaction between an ethanol cluster ion beam and a silicon surface was investigated. The sputtering depth of a silicon surface irradiated with an ethanol cluster ion beam increased with acceleration voltage. The number of disordered atoms on the silicon surface irradiated with an ethanol cluster ion beam initially showed a small dependence on retarding voltage and then a steep decrease with a further increase in retarding voltage.  相似文献   
154.
The fractal branch-and-bound method has been developed by the authors for stacking-sequence optimizations of symmetric and balanced composite laminates comprise of two in-plane and two out-of-plane lamination parameters. Cylindrical structures such as tanks or pipes, however, are usually made from balanced laminates. In the present study, therefore, we focus on the stacking-sequence optimizations of unsymmetrical composite laminates. In the unsymmetrical laminates, nine lamination parameters including three coupling-lamination parameters exist, and its feasible design region of fractal pattern is unrevealed. The paper clarifies the feasible region in which the in-plane, out-of-plane and coupling lamination parameters create fractal patterns of tetrahedrons or tetradecahedrons. Using the fractal patterns of lamination parameters, the improved fractal branch-and-bound method is proposed for unsymmetrical laminates including coupling lamination parameters. This new method is applied to stacking-sequence optimization problems of maximization of buckling load of cylindrical laminated shells. As a result, the method is successfully applied, and a practical optimal stacking sequence is obtained with low computational cost.  相似文献   
155.
Epidermal growth factor (EGF) signalling regulates normal epithelial and other cell growth, with EGF receptor (EGFR) overexpression reported in many cancers. However, the role of EGFR clusters in cancer and their dependence on EGF binding is unclear. We present novel single-molecule total internal reflection fluorescence microscopy of (i) EGF and EGFR in living cancer cells, (ii) the action of anti-cancer drugs that separately target EGFR and human EGFR2 (HER2) on these cells and (iii) EGFR–HER2 interactions. We selected human epithelial SW620 carcinoma cells for their low level of native EGFR expression, for stable transfection with fluorescent protein labelled EGFR, and imaged these using single-molecule localization microscopy to quantify receptor architectures and dynamics upon EGF binding. Prior to EGF binding, we observe pre-formed EGFR clusters. Unexpectedly, clusters likely contain both EGFR and HER2, consistent with co-diffusion of EGFR and HER2 observed in a different model CHO-K1 cell line, whose stoichiometry increases following EGF binding. We observe a mean EGFR : EGF stoichiometry of approximately 4 : 1 for plasma membrane-colocalized EGFR–EGF that we can explain using novel time-dependent kinetics modelling, indicating preferential ligand binding to monomers. Our results may inform future cancer drug developments.  相似文献   
156.
Redundant multi‐degree‐of‐freedom (MDOF) bilateral system in workspace is expected to be a key technology for the development of next‐generation robots because of the variety of feasible tasks. Nowadays, four‐channel bilateral structures based on acceleration control have been introduced to realize both position and force tracking in a bilateral control system. Additionally, torque observers have been implemented to facilitate force feedback without the use of torque/force sensors. However, differences in controller composition between the joint space and workspace are still unclear. In particular, observer designs in both spaces are important for a realization of torque/force sensorless bilateral control. This paper presents a performance evaluation of an MDOF force sensorless bilateral system performed by considering the design space of observers by numerical and experimental analyses. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(4): 70–80, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22481  相似文献   
157.
158.
Molten salt electrolysis using CaCl2 is employed to produce pure titanium and its alloys directly from TiO2 and a mixture of elemental oxides, respectively, as an alternate to the Kroll process. This is because CaO, which is a reduction by-product, is highly soluble in CaCl2. Good-quality titanium containing only a small amount of residual oxygen has been successfully produced and scaled to industrial levels. Thermochemical and electrochemical bases are reviewed to optimize the process conditions. Several processes using molten salt are being examined for future progress in titanium processing.  相似文献   
159.
Endotoxin release from Pseudomonas aeruginosa treated with cell wall-active carbapenem antibiotics and its effect on the production of tumor necrosis factor alpha and nitric oxide were examined. Treatment of bacteria with imipenem induced much lower levels of endotoxin release than treatment with meropenem. The endotoxin released was demonstrated to be of the smooth type and O-specific polysaccharide-rich. The exposure of the filtrates of P. aeruginosa treated with imipenem to physiologically relevant cells caused low-level production of tumor necrosis factor alpha and nitric oxide, while similar treatment with meropenem induced high levels of production.  相似文献   
160.
The rapid advance of computerization in industrial package design has led to a strong tendency toward CAD/CAM systems using personal computers for quick design and trial manufacturing. New tools based on a database of the cushioning properties of packaging materials will be needed for the design of package cushioning. Using a compression testing machine with computer control, an attempt has been made to construct such a database with registered characteristics for 47 samples of foamed polyethylene, foamed polypropylene and foamed polyethylene-polystyrene. This database offers the following functions and is recorded on floppy disk: (i) calculation of static cushioning properties (value); (ii) print-out of the computed results; (iii) drawing characteristic figures for designing package cushioning; (iv) indicating optimum value of static cushioning properties; (v) additional registration of new samples.  相似文献   
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