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61.
Turbulence is one of the most important phenomena in analyzing thermohydrodynamic characteristics of gas-liquid two-phase flow. For the purpose of accurate prediction of the turbulence phenomena, a basic conservation equation of Reynolds stress was derived based on the local instant formulation of mass and momentum conservations of two-phase flow. In this equation, interfacial transfer terms of turbulence appear as source terms. Detailed considerations on these transport terms were carried out. It was shown that they consist of a viscous damping term due to small scale interfacial structures, a drag induced turbulence generation term due to large scale interfacial structures and a term representing the exchange between surface energy and turbulence. Based on the mechanistic modeling and turbulence modulations, carried out were physical interpretations of interfacial area concentrations of small and large scale interfacial structures, a viscous damping term due to small scale interface and turbulence generation term due to large scale interface.  相似文献   
62.
A milk protein fraction with alkaline isoelectric points (milk basic protein, MBP) inhibits both bone resorption and osteoclastogenesis for in vitro models. We previously identified bovine angiogenin as a component of MBP that inhibits bone resorption. However, purified angiogenin had no effect on osteoclastogenesis, suggesting that MBP contains unidentified component(s) that inhibit osteoclast formation. In this study, we purified lactoperoxidase (LPO) as the predominant inhibitor of osteoclastogenesis in MBP. The LPO treatment downregulated levels of reactive oxygen species in osteoclasts. Signaling by receptor activator of NF-kappa-B ligand/receptor activator of NF-kappa-B (RANKL/RANK) was downregulated in LPO-treated cells, and, in particular, the ubiquitination of tumor necrosis factor receptor associate factor 6 (TRAF6) and activation of downstream signaling cascades (JNK, p38, ERK, and NFκB) were suppressed. Ultimately, LPO treatment led to decreased expression of c-Fos and NFAT2. These results suggest that MBP contains at least 2 components that independently suppress bone resorption through a unique mechanism: angiogenin inhibits bone resorption and LPO inhibits RANKL-induced osteoclast differentiation. These data explain many of the positive aspects of milk consumption on bone health.  相似文献   
63.
从Wine Lover晋级为酒奴,先是仅在餐厅侍酒师的安排下舒舒服服地享用美酒,进而开始购买为不同品种的葡萄设计的酒杯、某某名人签名的酒刀、一整套储酒设备,最后就自己做起窖主,甚至像sex and the city的Mr Big那样,在纳帕谷之类的风景圣地买下一块风水好地,正正经经做起庄主来了。  相似文献   
64.
Serizawa  Y. Takeshita  S. 《Electronics letters》1987,23(25):1353-1354
The received power frequency correlation coefficient taking account of amplitudes, phase path delays and angles of arrival of rays is derived theoretically to evaluate the frequency selectivity of multipath fading. An estimation of frequency selectivity reduction due to aperture antennas is presented by using ray tracing data.  相似文献   
65.
A method for calculating antenna-reflector combination gain for rectangular reflectors operating in the Fresnel region is derived instead of an approximate method based on an equi-area circular reflector. The scope of microwave application of the method is discussed, and reflector-equipped microwave links in operation are examined using the new method. A field test result using 50-GHz radio equipment with four types of reflectors shows good agreements with the theoretical calculations  相似文献   
66.
Poly(lactide)s stereocomplex ultrathin film with controlled structure at a molecular level was able to be prepared by stepwise assembly using the stereocomplex interaction. Pure stereocomplex crystal can be easily obtained by using this technique. When the substrates pre-coated with the stereocomplex assembly were immersed into solution of poly(L-lactide) or poly(D-lactide) for a long time, each polymer was homogeneously deposited on the substrates. The enantiomer was epitaxially crystallized on the stereocomplex film. The XRD pattern of the films showed similar characteristic peaks of the stereocomplex, indicating that the crystallization was influenced by conformation of polymer at the substrate. This is the first case of the epitaxially growth of polymers on the structurally regulated surface. These films had high degree of crystallinity although the assemblies did not undergo a crystallization process. This method was considered to be a general method that can be applied to other polymers, which able to form stereocomplex.  相似文献   
67.
A 67-year-old female with extensive inflammatory breast cancer was treated with oral chemoendocrine therapy using 5'-deoxy-5-fluorouridine (5'-DFUR) 1,200 mg and medroxyprogesterone acetate (MPA) 1,200 mg before intra-arterial infusion chemotherapy, which made the extensive inflammatory skin lesion improve remarkably. Sequential intra-arterial infusion made the skin lesion completely disappear. But the main tumor remained, so extended mastectomy was performed. These findings suggested that this therapy was effective for the prevention of extension of the skin lesion on the inflammatory breast cancer, and also served as induction therapy for this modality.  相似文献   
68.
The longitudinal and transverse wave velocities of polycrystalline MgO were successfully measured simultaneously and five types of elastic moduli, the Debye temperature, and the Grüneisen parameter were evaluated as functions of temperature from 298 to 1764 K. An aluminum foil was used as a couplant between the MgO specimen and waveguide. Both acoustic waves were successfully propagated into the specimen through the solid and liquid aluminum layers. In particular, no influence of melted aluminum foil on the acoustic wave velocities was observed. With increasing temperature, the Young's, shear, and bulk moduli decreased monotonically and the Grüneisen parameter and Poisson's ratio increased monotonically, which indicated a decrease in the ionic bonding strength. The Debye temperature decreased almost linearly with increasing temperature, which showed the effect of thermal expansion. Although previous investigators concluded that the Grüneisen parameter was almost independent of temperature, our data showed an obvious gradual increase in this parameter with temperature. In addition, our results implied the possibility of an abrupt increase in the Grüneisen parameter at temperatures less than 400 K. The slope of the Lamé parameter–temperature plot was almost zero over the entire investigated temperature range. On the basis of three‐dimensional volume‐nonpreserving shear, this behavior was interpreted as being caused by interlocking associated with the network of short Mg–O bonds.  相似文献   
69.
The radial stainless steel plates (RPs) used for Toroidal field (TF) coils in the International Thermonuclear Experimental Reactor (ITER) are 13 m long, 9 m wide and 10 cm thick, which are quite large. Even though they are very large structures, high manufacturing tolerances and high mechanical strength at 4 K are required. It is also required that each RP should be fabricated every three weeks. Therefore, the authors intend to develop efficient manufacturing methods for an ITER TF coil RP. Laser welding is then selected as a welding method for RP. Especially, the development of high technology laser welding is necessary to prevent hot cracking in the material used for the RP; namely, fully austenitic stainless steel with high nitrogen content. The authors carried out trial laser welding experiments aiming at its application to RP. As a result, it was effective to make the angle of back inclination of the weld head at a uniform welding speed. It also seemed that the sensitivity of hot cracking could be reduced by optimizing the chemical compositions of material used for RP. The base material and the welded joints satisfied mechanical properties in 4 K. The application of the laser welding technology to the fully austenitic stainless steel was therefore demonstrated.  相似文献   
70.
The combustion process of pyrotechnics was studied in order to obtain informations of the rate control parameters of burning rate. The pyrotechnics tested was made of Mg (magnesium) and TF (polyfluoroethylene). The burning rate measurements revealed that the burning rate of the Mg/TF propellants (pellet in shape) increases with increasing the weight fraction (ξ) of Mg in the range of ξ > 0.33. Though the adiabatic flame temperature is the maximum at ξ = 0.33, the burning rate increases with decreasing the flame temperature. The total burning surface area of the Mg particles mixed with in the unit mass of propellant plays an important role on the oxidation process in the gas phase just above the propellant burning surface. The heat flux feedback from the gas phase to the propellant burning surface increases with increasing ξ. Therefore, the burning rate increases as ξ increases.  相似文献   
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