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61.
A new contactless method for supplying energy to a fluidized bed is presented. An electromagnetic field supplies power to electro conductive inert particles. This technique is characterized by high energy densities and fast heating rates as well as high efficiency. It is essential in the metal processing industry. The experimental results show that the advantages of inductive heating can also be used for fluidized bed applications. The key aspect here is the determination of the time response and its parameters.  相似文献   
62.
Adults with attention-deficit/hyperactivity disorder (ADHD) were examined for early and late attentional processes as a function of controlled attention. The test paradigm was the attentional modulation of prepulse inhibition (PPI; early controlled attentional processing) and prepulse facilitation (PPF; late controlled attentional processing). In 49 patients and 49 controls, the authors measured acoustic startle responses to 96-dB startle pulses preceded 120, 240 (for PPI), 2,000, and 4,500 (for PPF) ms by a 68-dB prepulse noise. Geometric figures signaled that prepulses were to be ignored or attended to (automatic vs. controlled attention). ADHD patients exhibited deficits in prepulse modulation, but these reflected an interaction of controlled attention and time of information processing. Normal PPI and PPF occurred under all conditions except for controlled attentional modulation of PPI. Attention deficits in ADHD patients may reflect not general derangements in information processing or ability to attend but, rather, selective disturbances of controlled attention during early information processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
The synthesis of tetrahydro‐2,1‐benzisothiazolium salts 8 and cyclohepta[c] isothiazolium salts 11 by ring transformation of bicyclic isothiazolium perchlorates 2 , 3 is described and the by‐products 9 , 10 and 12 are characterized. Oxidation of the bicyclic salts 8 and 11 results in a new route to obtain ω‐(2‐aryl‐1,1,3‐trioxo‐2,3‐dihydro‐1H‐isothiazol‐4‐yl)‐alkanoic acids 17 and 18 by Criegee‐type‐rearrangement.  相似文献   
64.
The relative chain propagation constants and the regioselectivities of the oxidations of o-cymene and 2-isopropyl-1,4-dimethylbenzene were determined by competitive oxidations of the hydrocarbons with cumene. As expected, the reactivity of the tertiary C H bond of the isopropyl group is considerably decreased by o-methyl groups. Also in α-isopropylnaphthalene a considerable decrease in the reactivity of the tertiary C H bond takes place. The decrease of the chain propagation constants effects a decrease of the oxidabilities of o-substituted isopropyl aromatics. In the case of the methyl isopropyl benzenes the increase of the chain termination constants by primary peroxy radicals must also be taken into consideration. This results in a decrease of the oxidabilities which can be observed even in p-cymene (in comparison with cumene).  相似文献   
65.
Synthesis and UV-spectroscopic Characterization of Carbenium Ions on Aerosil The interaction of aerosil with various triphenylmethyl derivatives in the cationic vinyl polymerization in 1,2-dichloroethane was studied. The adsorption of the triphenylmethylium ions onto aerosil surfaces strongly depends on both the type of substituents (R   CH3,  OCH3,  Cl,  H and  NO2) and the nature of the counter anion (SbCl6, FeCl4, SnCl5, HSO4, SO42⊖, F, Cl, Br, CF3COO, N3 and SCN). The binding of the triphenylmethylium ions with aerosil occurs via nucleophilic anions such as halides. Counter anions derived from metal halides as MtXn+1 are not able bind on aerosil. Covalent compounds as triphenylmethyl halides are ionized by the acidic aerosil surface. The influence of substituents at the triphenylmethylium ion, the type of counter anions and the influence of water traces on surface — ionization are discussed.  相似文献   
66.
Progress curve experiments combined with optimal experimental design (OED) are an efficient approach to determine enzyme kinetics. However, it is hardly possible to verify why specific experiments are suggested for nonlinear enzyme kinetic model identification. Therefore, we systematically investigated the surface and contour plots of the sensitivities and of the OED criteria which are based on sensitivities. The model reaction was an enzyme catalyzed self‐ligation of aldehydes to chiral 2‐hydroxyketones. The visualization improved the understanding of OED and allowed for deducing and confirming five suggestions for kinetic identification: (1) Avoid experiments vicinal to the reaction equilibrium, (2) Choose the design space as large as possible, (3) Prefer D(eterminant)‐ and E(igenvalue)‐criteria over the A(verage)‐criterion, (4) Apply enzyme concentrations such that the reaction does not complete too fast, and (5) Few optimal experiments result in significantly improved parameter estimations. The graphical analysis also provides information about selecting appropriate optimization algorithms. © 2017 American Institute of Chemical Engineers AIChE J, 2017  相似文献   
67.
68.
According to most models of speech production, the planning of spoken words involves the independent retrieval of segments and metrical frames followed by segment-to-frame association. In some models, the metrical frame includes a specification of the number and ordering of consonants and vowels, but in the word-form encoding by activation and verification (WEAVER) model (A. Roelofs, 1997), the frame specifies only the stress pattern across syllables. In 6 implicit priming experiments, on each trial, participants produced 1 word out of a small set as quickly as possible. In homogeneous sets, the response words shared word-initial segments, whereas in heterogeneous sets, they did not. Priming effects from shared segments depended on all response words having the same number of syllables and stress pattern, but not on their having the same number of consonants and vowels. No priming occurred when the response words had only the same metrical frame but shared no segments. Computer simulations demonstrated that WEAVER accounts for the findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
Two incompatible pictures compete for perceptual dominance when they are presented to one eye each. This so-called binocular rivalry results in an alternation of dominant and suppressed percepts. In accordance with current theories of emotion processing, the authors' previous research has suggested that emotionally arousing pictures predominate in this perceptual process. Three experiments were run with pictures of emotional facial expressions that are known to induce emotions while being well controlled in terms of physical characteristics. In Experiment 1, photographs of emotional and neutral facial expressions were presented of the same actor to minimize physical differences. In Experiment 2, schematic emotional expressions were presented to further eliminate low-level differences. In Experiment 3, a probe-detection task was conducted to control for possible response-biases. Together, these data clearly demonstrate that emotional facial expressions predominate over neutral expressions; they are more often the first percept and they are perceived for longer durations. This is not caused by physical stimulus properties or by response-biases. This novel approach supports that emotionally significant visual stimuli are preferentially perceived. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
This study explores boundary-crossing networks in fuel-cell science and technology. We use the case of Norwegian fuel cell and related hydrogen research to explore techno-science networks. Standard bibliometric and patent indicators are presented. Then we explore different types of network maps — maps based on co-authorship, co-patenting and co-activity data. Different network configurations occur for each type of map. Actors reach different levels of prominence in the different maps, but most of them are active both in science and technology. This illustrates that to appreciate fully the range of science-technology interplay, all three analyses need to be taken into account.  相似文献   
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