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121.
Describes an experiment with 72 university students in which fear-relevant (snakes, spiders, and rats) and fear-irrelevant (flowers, mushrooms, and berries) pictures were compared as conditioned and instigating stimuli in a vicarious classical conditioning paradigm with skin conductance responses as the dependent variable. A female confederate model and an S watched the pictures side by side. After a few stimulus presentations, the experimenter (E) interrupted to investigate alleged overreactions of the model to one of the stimulus classes. The model then vividly described a phobia for this object, which was to serve as a vicarious instigating stimulus. The experiment continued for a few conditioning trials, and then the E announced that the disturbing stimulus would be omitted before the 2nd part of the experiment. There was no effect of stimulus content on vicariously instigated responses, although significant overall instigation was observed. However, the responses to the stimulus that was paired with the model's phobic stimulus, that is, the vicariously conditioned responses, failed to extinguish during the 2nd part of the experiment when it was fear-relevant but extinguished immediately when it was fear-irrelevant. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
122.
A theoretical analysis of the gain properties of m.e.s.f.e.t. drain mixers is presented. The m.e.s.f.e.t. model includes the nonlinearity of both the transconductance and the drain resistance. For a special case, a simple analytical expression for the gain is given. Numerical results for a typical example are briefly presented as an illustration. 相似文献
123.
124.
Transparent refractive-index matched micro (TRIMM) particles have proved to be an excellent scattering component for use in translucent sheets. Measurements of hemispheric transmittance and reflectance versus angle of incidence, as well as angle-resolved studies of such translucent sheets, have been carried out to complement earlier published hemispheric reflectance and transmittance spectral measurements carried out at normal angle of incidence. Hemispheric values relative to angle of incidence are of interest for daylighting applications and building simulations, and angle-resolved measurements are vital for verifying that our modeling tools are reliable. Ray-tracing simulations based on Mie scattering for the individual TRIMM particles and angle-resolved measurements are in good agreement, indicating that the simulation method used is practical for the design of new scattering profiles by varying particle concentration or refractive index. 相似文献
125.
Miecislaw Taube 《Atomic Energy》1967,22(1):10-13
An attempt is made to classify fast reactors . Versions of a fast reactor with liquid fuel in a boiling coolant - solvent are considered separately. The advantages of this type of reactor and the feasibility of its construction are evaluated; the basic characteristics of the reactor are derived.Institute of Nuclear Research, Warsaw-Zeran, Polish People's Republic. Translated from Atomnaya Énergiya, Vol.22, No.1, pp. 10–13, January, 1967. 相似文献
126.
Massimo F. Bertino Bernd Smarsly Antonio Stocco Arne Stark 《Advanced functional materials》2009,19(8):1235-1240
A technique is presented that allows for altering of the physical characteristics of films of TiO2 nanoparticles by exposure to visible light. In this technique, dye‐sensitized oxide nanoparticles are deposited on a substrate by dip‐coating. Photodissociation of the organic ligand layer leads to cross‐linking of the nanoparticles. Consequently, irradiated films have a decreased porosity, an increased index of refraction and an increased hydrophobicity. Films irradiated with green light are compared to films irradiated with UV light. Within experimental error, visible‐ and UV‐illumination induces the same changes in the films. The mechanism of surfactant elimination in dye‐sensitized oxide particles is discussed, patterning is demonstrated, and prospective applications of the technique are considered. 相似文献
127.
Xinliang Feng Yanyu Liang Linjie Zhi Arne Thomas Dongqing Wu Ingo Lieberwirth Ute Kolb Klaus Müllen 《Advanced functional materials》2009,19(13):2125-2129
One‐dimensional fibers and tubes are constructed through the oriented carbon‐carbon cross‐linking reactions towards rigid conjugated polymer networks. As the result, a template‐free and one‐step synthesis of CNTs and CNFs is achieved through a simple carbonization of the as‐formed carbon‐rich tubular and fiberlike polyphenylene precursors under argon. Microporous CNTs and CNFs with a surface area up to 900 m2 g–1 are obtained, together with HR‐TEM characterizations indicating the formation of intrinsic microporous structure in these rigid carbon‐rich networks. The primary electrochemical experiments reveal their promising applications as advanced electrodes in electrochemical double‐layered capacitor (EDLC). 相似文献
128.
The removal of beta blockers and psycho-active drugs was investigated in a representative conventional German WWTP by long-term measurement campaigns along different biological treatment processes. The activated sludge treatment with an elevated SRT of 18 d was the only process which led to a significant removal of certain beta blockers and psycho-active drugs. The removal efficiency was below 60% for all compounds except for the natural opium alkaloids codeine and morphine being removed by more than 80%. Primary biological transformation and sorption onto sludge as the main removal mechanisms were examined in lab-scale batch experiments. Sorption onto activated sludge was found to be negligible (<3%). The biological transformation could be described by pseudo-first order kinetics and the transformation constants kbiol were used to predict the removal of beta blockers and psycho-active drugs in an activated sludge unit with a model. For most compounds the removal efficiencies measured on the full-scale WWTP were within the 95% confidence intervals predicted by the model. The results from full-scale measurements and modeling indicate that biological transformation in the nitrification tank together with parameters such as the sludge retention time and the temperature is crucial regarding the biological transformation of beta blockers and psycho-active drugs in conventional WWTPs. 相似文献
129.
99Tc- and 239Pu-Doped Glass Leaching Experiments: Residual Alteration Rate and Radionuclide Behavior
Séverine Rolland Magaly Tribet Christophe Jégou Véronique Broudic Magali Magnin Sylvain Peuget Thierry Wiss Arne Janssen Antoine Blondel Pierre Toulhoat 《International Journal of Applied Glass Science》2013,4(4):295-306
The long-term behavior of high-level nuclear glass subjected to alpha/beta radiation by long-life radionuclides must be investigated with respect to geological disposal. This study focuses on the effects of alpha and beta radiations on the chemical reactivity of R7T7 glass with pure water, mainly on the residual alteration rate regime. Glass specimens doped with 0.85 wt% 239PuO2 (α emitter) and 0.24 wt% 99TcO2 (β emitter) that simulate alpha and beta dose rate corresponding to long-term disposal conditions are leached under static conditions in argon atmosphere at 90°C, in initially pure water and at a high surface-area-to-volume ratio (S/V = 20/cm). The alteration rate is monitored by the release of glass alteration tracer elements (B, Na, and Li). Radiation effects on the leached glass and its gel network are characterized by SEM and TEM analyses. Plutonium and technetium releases are also measured by radiometry, and their chemical oxidation state is assessed by measuring the pH and reduction–oxidation potential of the leachates. The results do not highlight any significant effect of alpha/beta radiation on the residual alteration of these doped glasses. These observations are consistent with solid characterizations, which show that a protective layer can be formed under such irradiation fields. Under our experimental conditions (Eh~380 mV/SHE, pH90°C = 8–8.6), very low concentrations of soluble plutonium are measured in the leachate, indicating strong plutonium retention, whereas technetium performs as a soluble element and is not retained in the altered layer. 相似文献
130.
Víctor P. Gil Jiménez Thomas Eriksson Ana García Armada M. Julia Fernández-Getino García Tony Ottosson Arne Svensson 《Wireless Personal Communications》2008,47(1):101-112
In this paper, several algorithms for compressing the feedback of channel quality information are presented and analyzed.
These algorithms are developed for a proposed adaptive modulation scheme for future multi-carrier 4G mobile systems. These
strategies compress the feedback data and, used together with opportunistic scheduling, drastically reduce the feedback data
rate. Thus the adaptive modulation schemes become more suitable and efficient to be implemented in future mobile systems,
increasing data throughput and overall system performance.
相似文献
Arne SvenssonEmail: |