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141.
The off response of the P III component isolated by aspartate in the human eyecup in vitro showed an initial rapid decay followed by a slow decay. The rapid decay in the human ERG originates mainly in cones. The rapid decay was also observed in human subjects. The spectral sensitivity curve of the rapid decay was found to be shifted toward short wavelengths in all nine protanopes tested. In these cases of protanopia, anomalous cone functions were indicated.  相似文献   
142.
Probabilistic fuel pin gap distributions within a wire-spaced fuel subassembly and sensitivities of the related uncertainties to fuel pin gaps are discussed. The analyses consist mainly of expressing a local fuel pin gap in terms of sensitivity functions of the related uncertainties and calculating the corresponding probabilistic distribution through taking all the possible combinations of the distribution of uncertainties. The results of illustrative calculations show that with the reliability level of 0.9987, the maximum deviation of the pin gap at the cladding hot spot of a center fuel subassembly is 8.05% from its nominal value and the corresponding probabilistic pin gap distribution is shifted to the narrower side due to the external confinement of a pin bundle with a wrapper tube.  相似文献   
143.
144.
The deformation up to fracture at 150 K was undertaken on α-β brass two-phase bicrystals. The variation of the slip systems during the proceeding deformation was studied and explained on the basis of incompatible stresses. The normal stress-strain curves were analyzed for various types of bicrystals and the bending that appeared in the specimens when unloaded was explained with respect to the occurrence of the Bauschinger effect in the α phase. Fracture modes other than those observed at room temperature were present. The results, and other minor problems, were discussed.  相似文献   
145.
It is known that a behavior-based control approach is effective for acquiring an intelligent control system of robots. However, further improvements are required for making any behavior-based control system robust against changes in the environments. A module learning method has been applied in the framework of fuzzy behavior-based control to have an adaptive behavioral fusion. In this paper, an adaptive fusion strategy is proposed to adaptively select a cooperative fusion unit or competitive fusion unit, depending on the external sensor information. Some simulations are given to illustrate that the present control systems are flexible against the change of environments or untrained environments, compared to those with a conventional priority-based fusion unit.  相似文献   
146.
The moderately thermophilic bacterium Bacillus subtilis WU-S2B desulfurized dibenzothiophene (DBT) at 50 degrees C through the selective cleavage of carbon-sulfur bonds. In this study, three enzymes involved in the microbial DBT desulfurization were purified and characterized. The first two enzymes, DBT monooxygenase (BdsC) and DBT sulfone monooxygenase (BdsA), were purified from the wild-type strain, and the last one, 2'-hydroxybiphenyl 2-sulfinic acid desulfinase (BdsB), was purified from the recombinant Escherichia coli overexpressing the gene, bdsB, with chaperonin genes, groEL/ES. The genes of BdsC and BdsA were also overexpressed. The molecular weights of BdsC and BdsA were determined to be 200 and 174 kDa, respectively, by gel filtration chromatography, suggesting that both enzymes had four identical subunits. BdsB had a monomeric structure of 40 kDa. The three enzymes were characterized and compared with the corresponding enzymes (DszC, DszA, and DszB) of mesophilic desulfurization bacteria. The specific activities of BdsC, BdsA, and BdsB were 84.2, 855, and 280 units/mg, respectively, and the latter two activities were higher than those of DszA and DszB. The heat stability and optimum temperature of BdsC, BdsA, and BdsB were higher than those of DszC, DszA, and DszB. Other enzymatic properties were investigated in detail.  相似文献   
147.
Dodecyl and dodecanoyl groups (C12) are attached at the chain ends of poly[N5-(2-hydroxyethyl) l-glutamine] (PHEG), and association behavior of this both-ends hydrophobically modified water soluble polypeptide (C12-PHEG-C12) has been investigated by means of light scattering measurements. Water/ethylene glycol (EG) mixed solvents were used as selective solvent for PHEG block, and PHEG changed its structure from random-coil state to α-helix with increasing EG content in the mixed solvent (WEG). When WEG is less than 0.5, flower-like micelle with C12 associated core and PHEG corona in loop conformation was suggested to be formed. Increase of WEG from 0.5 to 0.6 induced drastic increase of association number and size of the associate, in which many C12 associated cores may be connected by PHEG in bridge conformation. This structure change of associate is considered to be driven by the increase of helix content of PHEG with WEG, which enhances the possibility to form bridge conformation because of its rigidity. Solution preparation method, i.e. order of addition of solvent, was found to influence the structure of associate, although its effect on the helix content of PHEG was negligible.  相似文献   
148.
An experimental guided millimeter-wave transmission system is constructed employing two 806-Mbit/s digital repeaters, an 8.4-km waveguide line loop, and channel coupling networks. This paper presents its characteristics, such as waveforms, amplitude and delay, error rate, and timing jitter in some detail.  相似文献   
149.
The heat capacities of metallic uranium and thorium from 80 to 1000 K have been determined by laser-flash calorimetry. The results on uranium agree very well with those in the literature over the temperature range investigated. The results on thorium are several percent lower than the heat-capacity values hitherto reported, while the enthalpy data at high temperatures in the literature are in good agreement with the present results. Shomate's analysis showed that the present results are the most consistent through the temperature range from 80 to 1000 K. On this, a revised table of thermodynamic functions of thorium from 80 to 1000 K is presented. The excess heat capacity on thorium has been found to be not appreciable up to 1000 K, in contrast with the large excess heat capacity above 300 K for uranium.  相似文献   
150.
Deformation modes have been investigated in metastable beta Ti-15Mo-5Zr alloy single crystals using both transmission electron microscopy techniques and multisurface trace analysis. {332} twinning and 〈111〉 crystallographic slip were observed to occur at an initial stage of deformation depending on deformation axis. {332} twinning occurs in a crystal whose tensile axis lies around 〈111〉, while 〈111〉 slip appears in a crystal having the tensile axis in the neighborhood of 〈001〉 to 〈011〉. The twinning system which possesses the maximum resolved shear stress is always operative in both tensile and compressive deformations. Single crystals of this alloy exhibit an asymmetry of the active slip plane and of the yield stress in a manner similar to other bcc metals and dilute alloys.  相似文献   
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