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1.
The Word Accentuation Test assesses the accentuation of 30 infrequent Spanish words written without the accentuation mark and is an easy-to-use tool for estimating premorbid intelligence of Spanish-speaking people. Its intraobserver (0.97) and interobserver (0.93) reliabilities and its correlation with the Wechsler Adult Intelligence Scale (.837) and Raven's Progressive Matrices (.655) are high, offering a good prediction of general intelligence. It is resistant to mental deterioration; 20 demented and 40 controls matched by sex, age, and education obtained similar scores. The discrepancies between current and predicted scores in Raven's scale can diagnose mild-moderate dementia with 0.79 accuracy (sensitivity, 0.78; specificity, 0.82).  相似文献   
2.
Study on the Anti-Coking Nature of Ni/SrTiO3 Catalysts by the CH4 Pyrolysis   总被引:1,自引:0,他引:1  
A solid phase crystallization (spc) method was applied for the preparation of SrTiO3-supported Ni catalysts and compared to the impregnation (imp) method. spc-Ni0.2/SrTiO3 has highly dispersed and stable Ni metal particles resulting in higher activity and higher sustainability against coking than imp-Ni0.2/SrTiO3 in the partial oxidation of CH4. Both catalysts were tested for the CH4 pyrolysis in order to elucidate the catalytic nature against coking of spc-Ni0.2/SrTiO3. The amount of carbon and the rate of H2 formation were similar over both catalysts at both 773 and 1073 K. On both catalysts, CH4 continuously decomposed at 773 K, while the rate of CH4 pyrolysis quickly decreased at 1073 K. Fibrous carbons grew up with a Ni metal particle on the tip of the fiber at 773 K, while carbon balls and short carbon fibers with a Ni metal particle encapsulated inside formed and no sufficient growth of the fiber was observed at 1073 K. The carbon species formed at 773 K was hydrogenated completely to CH4 around 873 K, while the hydrogenation of that formed at 1073 K needed higher temperature around 1073 K. However, the carbon species formed on both the catalysts at either 773 or 1073 K was completely oxidized around 773 K. Thus, judging from the anti-coking nature, the behaviors in the CH4 pyrolysis are similar over both catalysts, nonetheless spc-Ni0.2/SrTiO3 was far superior to imp-Ni0.2/SrTiO3 in the CH4 oxidation. It is likely that the high sustainability against coking of spc-Ni0.2/SrTiO3 is not due to its intrinsic nature suppressing the coking but due to its high activity of reforming which can quickly eliminate the carbon formed on the catalyst surface.  相似文献   
3.
When electric resistivity of Thick Film Resistor (TFR) is adjusted to the desired value, laser beam is irradiated onto the resistor material so that a part of the resistor material is instantaneously vaporized and cut away. This conventional laser trimming method to adjust the resistivity of TFRs is an indispensable technique for manufacturing elec-tronic devices such as hybrid ICs. A peculiar phenomena was revealed by us, that is, when specially selected pulse laser beams were irradiated to TFR, the TFR was surface modified without cutting grooves, and then resistivity of the TFR was decreased. We completed the advanced laser process to apply this peculiar phenomena. 8 By comparing with conventional trimming processes, we can show prominent features of the advanced process, for example, resistivity of fine size TFR (300 micrometers-width and under) can be easily controlled. The decrease in resistivity of the TFR is considered to result from the decrease in specific resistivity of glass in the TFR. Because it is considered that the glass in the TFR is heavily doped with ruthenium impurities during the surface modification due to results of morphology observations and x-ray diffraction analysis. We have applied this advanced laser process to fine size TFR (300 micrometers-width), and developed high density hybrid ICs.  相似文献   
4.
Cytochrome bo is a four-subunit quinol oxidase in the aerobic respiratory chain of Escherichia coli and functions as a redox-coupled proton pump. Subunit I binds all the redox metal centers, low-spin heme b, high-spin heme o, and CuB, whose axial ligands have been identified to be six invariant histidines. This work explored the possible roles of the aromatic amino acid residues conserved in the putative transmembrane helices (or at the boundary of the membrane) of subunit I. Sixteen aromatic amino acid residues were individually substituted by Leu, except for Tyr61 and Trp282 by Phe and Phe415 by Trp. Leu substitutions of Trp280 and Tyr288 in helix VI, Trp331 in loop VII-VIII, and Phe348 in helix VIII reduced the catalytic activity, whereas all other mutations did not affect the in vivo activity. Spectroscopic analyses of the purified mutant enzymes revealed that the defects were attributable to perturbations of the binuclear center. On the basis of these findings and recent crystallographic studies on cytochrome c oxidases, we discuss the possible roles of the conserved aromatic amino acid residues in subunit I of the heme-copper terminal oxidases.  相似文献   
5.
The effects of serrated grain boundaries on the creep-rupture properties of wrought cobaltbase HS-21 alloys were investigated at 1311 and 1422 K. The amount of grain-boundary sliding and the initiation and growth of grain-boundary cracks were also examined during creep at 1311 K. Specimens with serrated grain boundaries exhibited longer rupture life and larger rupture ductility than those with straight grain boundaries, but these specimens had almost the same rupture life and rupture ductility under lower stresses at 1422 K, because serrated grain boundaries were also formed in specimens with originally straight grain boundaries. The average amount of grain-boundary sliding during creep at 1311 K increased with time (or with creep strain), but was almost the same in both specimens with serrated grain boundaries and those with straight grain boundaries at the same creep strain. Grain-boundary cracks or voids initiated in the early stage of creep in those specimens at 1311 K. Therefore, the strengthening by serrated grain boundaries at high temperatures above about 1311 K was attributed to the retardation of growth and linkage of grain-boundary cracks and voids.  相似文献   
6.
We studied the response of a predatory thrips, Scolothrips takahashii, towards herbivore-induced plant volatiles emitted by Lima bean plants infested by two-spotted spider mites Tetranychus urticae (green form). Tests were conducted with a Y-tube olfactometer in the laboratory and with traps under field conditions. The odor of artificially damaged and uninfested Lima bean leaves was not more attractive than clean air in the Y-tube olfactometer. The predatory insects showed a greater preference for Lima bean leaves infested by the two-spotted spider mites than for either clean air or uninfested bean leaves. They showed the same preference towards infested leaves from which all spider mites and their visible products had been removed. Neither the spider mites themselves nor their products attracted the predators. In a satsuma mandarin grove, two traps with infested Lima bean plants as an odor source attracted 42 adult S. takahashii in 55 days, whereas no S. takahashii were trapped in two control traps with uninfested Lima bean plants during the same period. No S. takahashii were found during this period in the vicinity of either the sample traps or the control traps (5-m radius of each trap). These data showed that S. takahashii use herbivore-induced plant volatiles in their foraging behavior in natural ecosystems.  相似文献   
7.
High luminance Y3Al5O12:Ce3+ (YAG:Ce) nanoparticles were prepared from urea-added nitrate aqueous precursor by flame-assisted spray pyrolysis (FASP). The addition of urea into nitrate precursor plays an important role in YAG:Ce nanoparticle formation and in improving its optical performance. The decomposition and combustion of urea in the flame zone provides additional heat to the particles, which coupled with the evolution of large volumes of gasses, contributes to nanoparticle formation. The as-prepared nanoparticles are hexagonal YAlO3, that are nearly spherical, rough on the surface and dense—and they can be converted to YAG:Ce after being annealed at 1200 °C for 4 h. The heat-treated particles are single crystalline, smooth in surface and dense with an average size around 50 nm. The optimum cerium-doping concentration of YAG:Ce nanoparticles is 4.0 at.%, which exhibits quantum efficiency of 45.0%. This quantum efficiency is comparable with that of YAG:Ce nanoparticles produced from other processes. The efficient emission of YAG:Ce nanoparticles also originates from a relatively good distribution of Ce ions incorporated into the host material of YAG as evidenced from the elemental mapping analysis.  相似文献   
8.
Gallium nitride (GaN) nanoparticles were successfully produced from nano-sized gallium oxide (Ga2O3) particles under a flow of ammonia gas. The gallium oxide nanoparticles were prepared by salt-assisted spray pyrolysis (SASP). Highly crystalline Ga2O3 nanoparticles with an average diameter of approximately 10 nm were obtained at various temperatures when a flux salt (LiCl, 5 mol/l) was added to the precursor solution. The effects of the crystallinity of the Ga2O3 particles and nitridation time on transformation to GaN were characterized using X-ray diffraction and scanning/transmission electron microscopy. Highly crystalline GaN nanoparticles with a mean size of 23.4 nm and a geometric standard deviation of 1.68 nm were obtained when Ga2O3 nanoparticles with relatively low crystallinity were used as the starting material. The resulting GaN nanoparticles showed a photoluminescence peak at 364 nm under UV excitation at 254 nm.  相似文献   
9.
Highly crystalline and hexagonal single-phase cesium tungsten bronze (Cs0.32WO3) nanoparticles were successfully synthesized by a flame-assisted spray pyrolysis followed by annealing under a reducing gas atmosphere. The resulting Cs0.32WO3 nanoparticles featured a pure hexagonal Cs0.32WO3 phase with a high crystallinity and homogeneous chemical composition. Unlike conventional methods, the proposed process in this paper has several advantages, including a short reaction time and the ability to yield products with high purity and good energy efficiency. Furthermore, the Cs0.32WO3 nanoparticles produced in this research showed a remarkable near-infrared shielding ability with a 97.7% cut-off at 1500?nm.  相似文献   
10.
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