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961.
The authors investigated the impact of response activation on dual-task performance by presenting a subliminal prime before the stimulus in Task 2 (S2) of a psychological refractory period (PRP) task. Congruence between prime and S2 modulated the reaction times in Task 2 at short stimulus onset asynchrony despite a PRP effect. This Task 2 congruence effect was paralleled by a Task 1 congruence effect and emerged exclusively under conditions of cross talk, whereas it did not occur under dual-task conditions preventing cross talk between tasks. This suggests that response activation operates during the PRP in dual tasks and affects the response times in Task 2 via cross talk between common processing elements at prebottleneck stages but not by directly affecting the postbottleneck stages. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
962.
S. Abderrahmane A. Himour L. Ponsonnet 《Materials science & engineering. C, Materials for biological applications》2008,28(5-6):901-905
This work is devoted to the biocides effects by electrochlorination under a pulsated bipolar polarization (PBP) of low potentials (− 1 V/cm to + 1.6 V/cm). Two working electrodes were used, one in platinum and the other in AISI 430 stainless steel, in two different electrolytes: sterilized distilled water and 0,9N sterilized NaCl solution, contaminated by E. Coli or by Pseudomonas Aeruginosa. The inactivation of these bacteria was established under the action of three biocide treatments: E.F (Electric Field); the combination of E.F and Active Chlorine (A.C) and the combination of E.F, A.C and Ions in Solutions (I.S). The synergistic effect of these treatments leads to a high efficiency in disinfection. The results showed that the total inactivation of the E. Coli stain is reached in half a minute, while that of P. aeruginosa is reached in 20 min. The use of an economic stainless steel electrode allowed us to observe that, for pulsate frequencies higher than 103 s− 1, the formation of active chlorine increased whereas the corrosion speed decreased. 相似文献
963.
Phosphating of cold-rolled steel was investigated. A dense, uniform and fine-grained zinc phosphate crystalline layer was observed after nickel activation. These crystal-line layers were shown to have improved strength, durability and corrosion resistance. The mechanism of the growth of the zinc phosphate layer is discussed. 相似文献
964.
本文研究了二辛基硫醚的萃取性能并将其用于地质样品中痕量银的中子活化分析(NAA)。将地质样品于反应堆(中子通量为(4-7)×10~(13)n/cm~2·s)中照射200h,冷却一个月以上,用HF-HNO_3-HClO_4分解样品,于1N HNO_3介质中用0.2M二辛基硫醚-氯仿溶液萃取,有机相作Ge(Li)γ谱分析,用相对比较法求出样品中银含量。化学产额为92%。分析了水系沉积物、岩石和土壤标样,测得银的含量范围为0.023-4.35ppm,实际样品的测定精密度在±15%以内。 相似文献
965.
Effect of the activation procedure on the performance of Mo/H-MFI catalysts for the non-oxidative conversion of methane to aromatics 总被引:1,自引:0,他引:1
Sharifah B. Derouane-Abd Hamid J. Ross Anderson Iver Schmidt Christophe Bouchy Claus J. H. Jacobsen Eric G. Derouane 《Catalysis Today》2000,63(2-4):461-469
The effect of pre-treatment on the performance of Mo/H-MFI zeolite catalysts applied to the non-oxidative conversion of methane to aromatics has been investigated. It is demonstrated that catalyst performance depends on activation conditions. Activation of the Mo-oxide/H-MFI precursor with an n-butane/hydrogen mixture results in higher catalyst stability and benzene selectivity which are tentatively attributed to the formation of the -MoC1−x carbide, with f.c.c. structure as revealed by XRD. 相似文献
966.
Nicolas Plumeré 《Electrochimica acta》2007,53(3):1244-1251
The surface of spherical nonporous monodisperse silica particles (diameter: 200 nm) is covalently modified with hydride by means of hydrosilanization. A direct silicon-carbon link between the hydride modified silica surface and 10-undecylenic acid is obtained by photochemical radical initiated hydrosilylation. A ferrocene unit is attached through an amide link to the carboxylic acid modified surface. Solid-state NMR and DRIFT spectroscopy indicate success of the reactions. The electrochemical oxidation and reduction of the ferrocene modified silica particles are observed after their adsorption on a platinum electrode. The cyclic voltammograms indicate, in addition to the charge transfer between ferrocene units on the particle surface, an interparticle charge transfer. 相似文献
967.
Performance of carbon-carbon supercapacitors based on organic, aqueous and ionic liquid electrolytes 总被引:1,自引:0,他引:1
Andrzej Lewandowski Angelika Olejniczak Maciej Galinski Izabela Stepniak 《Journal of power sources》2010,195(17):5814-159
Properties of capacitors working with the same carbon electrodes (activated carbon cloth) and three types of electrolytes: aqueous, organic and ionic liquids were compared. Capacitors filled with ionic liquids worked at a potential difference of 3.5 V, their solutions in AN and PC were charged up to the potential difference of 3 V, classical organic systems to 2.5 V and aqueous to 1 V. Cyclic voltammetry, galvanostatic charging/discharging and impedance spectroscopy were used to characterize these capacitors. The highest specific energy was recorded for the device working with ionic liquids, while the highest power is characteristic for the device filled with aqueous H2SO4 electrolyte. Aqueous electrolytes led to energy density an order of magnitude lower in comparison to that characteristic of ionic liquids. 相似文献
968.
Seo Hee Ju 《Journal of power sources》2010,195(13):4327-9158
High-density Li4Ti5O12 powders comprising spherical particles are prepared by spray pyrolysis from a solution containing dimethylacetamide (drying control chemical additive) and citric acid and ethylene glycol (organic additives). The prepared powders have high discharge capacities and good cycle properties. The optimum concentration of dimethylacetamide is 0.5 M. The addition of dimethylacetamide to the polymeric spray solutions containing citric acid and ethylene glycol helps in the effective control of the morphology of the Li4Ti5O12 powders. At a constant current density of 0.17 mA g−1, the initial discharge capacities of the powders obtained from the spray solution with and without the organic additives are 171 and 167 mAh g−1, respectively. 相似文献
969.
Kitiya Hongsirikarn James G. Goodwin Jr. Scott Greenway Stephen Creager 《Journal of power sources》2010,195(1):30-38
The effect of NH3 and NH4+ poisoning on the conductivity of Nafion membranes was investigated via electrochemical impedance spectroscopy. The conductivities of membranes prepared with different NH4+ compositions were measured in deionized water at room temperature and compared to those at 80 °C in a gas phase for various relative humidities. The liquid-phase conductivity decreased linearly with an increase in the NH4+ composition in the membrane (yNH4+), with that of the NH4+-form having a conductivity 25% that of the H+-form. The gas-phase conductivity of the NH4+-form, on the other hand, declined by 66–98% relative to the H+-form depending on humidity. The conductivities of fresh membranes in the presence of gas-phase NH3 at different humidities were also studied. The conductivity decreased with time-on-stream and reached the same conductivity at a given humidity regardless of the NH3 concentration, but the time to reach steady-state varied with NH3 concentration. The yNH4+ at steady-state conductivity was equivalent for all the NH3 concentrations studied. The kinetics of conductivity decrease was slower at higher humidities. The humidity and yNH4+ appear to have a concerted effect on the conductivity. The quantitative conductivity data under practical fuel cell conditions should be useful for future fuel cell modeling. 相似文献
970.
快淬 TiZrVMnNi 贮氢合金的电化学性能研究 总被引:2,自引:0,他引:2
对比研究了熔体旋转和常规铸态Ti0 .8Zr0 .2 Mn0 .5V0 .5Ni1.0 贮氢合金的电化学特性。发现快淬态与铸态合金的活化性能都很好 ,经过 1~ 3次充放电循环 ,就可达到最大放电容量。快淬工艺明显提高了合金的放电容量 ,并且淬速与放电容量之间在一定情况下出现峰值。快淬工艺同时改善合金的放电电压特性 ,使合金的放电平台更平 ,平台电压更高。但是快淬钛基贮氢合金的循环稳定性能和铸态合金一样差 ,放电容量在 10次内急剧衰减。 相似文献