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211.
Most Hebrew words are composed of 2 intertwined morphemes: a triconsonantal root and a phonological word pattern. Previous research with conjugated verb forms has shown consistent priming from the verbal patterns, suggesting that verbal forms are automatically parsed by native speakers into their morphemic constituents. The authors investigated the decomposition process, focusing on the structural properties of verbal forms that are perceived and extracted during word recognition. The manipulations consisted of using verbal forms derived from "weak" roots that have one consonant missing in some of the forms. The results demonstrated that if 1 consonant is missing, the parsing system collapses, and there is no evidence for morphological priming. In contrast, when a random consonant is inserted into the weak form, the verbal-pattern priming re-emerges. This outcome suggests that the constraint imposed on the decomposition process is primarily structural and abstract. Moreover, the all-or-none pattern of results is characteristic of rule-based behavior and not of simple correlational systems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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213.
Parking garage “Am Gericht” in Frankfurt am Main – a refurbishment with cathodic corrosion protection. After several decades in use a refurbishment is often necessary for the bearing structure of reinforced concrete parking garages due to chlorides, which have been brought into concrete by road salt, and the resulting corrosion of the reinforcement, which may lead to a serious decrease of the bearing capacity. With the system of the cathodic protection of the reinforcement exists a cost‐effective and reliable technique as an alternative to common solutions. An intensive investigation of the structure, the knowledge of the reasonable limits of the system, excellent design and execution of the construction work and the monitoring of the working system are nevertheless required, which is illustrated by the example of the parking garage “Am Gericht” in Frankfurt am Main. 相似文献
214.
Marcelo Carmo Thorsten Roepke Amilton M. dos Santos Marcelo Linardi 《Journal of power sources》2009,191(2):330-337
The objective of this study is to graft the surface of carbon black, by chemically introducing polymeric chains (Nafion® like) with proton-conducting properties. This procedure aims for a better interaction of the proton-conducting phase with the metallic catalyst particles, as well as hinders posterior support particle agglomeration. Also loss of active surface can be prevented. The proton conduction between the active electrocatalyst site and the Nafion® ionomer membrane should be enhanced, thus diminishing the ohmic drop in the polymer electrolyte membrane fuel cell (PEMFC). PtRu nanoparticles were supported on different carbon materials by the impregnation method and direct reduction with ethylene glycol and characterized using amongst others FTIR, XRD and TEM. The screen printing technique was used to produce membrane electrode assemblies (MEA) for single cell tests in H2/air (PEMFC) and methanol operation (DMFC). In the PEMFC experiments, PtRu supported on grafted carbon shows 550 mW cm−2 gmetal−1 power density, which represents at least 78% improvement in performance, compared to the power density of commercial PtRu/C ETEK. The DMFC results of the grafted electrocatalyst achieve around 100% improvement. The polarization curves results clearly show that the main cause of the observed effect is the reduction in ohmic drop, caused by the grafted polymer. 相似文献
215.
Steel composite construction of the bow buildings at the Berlin Main station. Currently Berlin main station, Europe's largest crossway terminal, is under construction next to the government quarter. The east‐west glass roof intersects two buildings. These “bow‐buildings” highlight the underground north‐south track in a characteristic way. The north‐south glass roof, measuring 180 m, is hanging between these buildings. The “bow‐buildings” are office towers with 12 storeys. The steel composite structure is on the outside of the cladding. The buildings in form of a bridge are remarkable. They consist of 4 storeys an have a span of 87 m. 相似文献
216.
Occurrence, sources, and fate of benzothiazoles in municipal wastewater treatment plants 总被引:2,自引:0,他引:2
A set of six benzothiazoles was determined in effluents of three municipal wastewater treatment plants. Total concentrations of benzothiazoles ranged from 1.9 to 6.7 microg/ L, with benzothiazole-2-sulfonate (BTSA) being most prominent (35 - 70%), followed by benzothiazole, 2-hydroxybenzothiazole, and 2-methylthi benzothiazole (MTBT). The removal of benzothiazoles in tertiary municipal wastewater treatment was investigated in more detail in one of the plants during two sampling periods of several weeks. Total benzothiazole concentration decreased by 5-28% only. This very limited removal was primarily due to BTSA and MTBT that were either hardly removed or even increased in concentration. In street runoff benzothiazoles exceeded the wastewater concentrations by 1 order of magnitude, showing that surface runoff can be a significant source of benzothiazole emission. In household wastewater total concentrations were in the range of 50-80% of that found in municipal wastewater. These investigations outline that benzothiazoles, a class of polar and biologically active industrial chemicals, are regularly released with treated municipal wastewater and exhibit a considerable lifetime in surface waters. 相似文献
217.
Hristov AN Lee C Cassidy T Long M Heyler K Corl B Forster R 《Journal of dairy science》2011,94(1):382-395
The objectives of this experiment were to investigate the effects of lauric (LA) and myristic (MA) acids on ruminal fermentation, production, and milk fatty acid (FA) profile in lactating dairy cows and to identify the FA responsible for the methanogen-suppressing effect of coconut oil. The experiment was conducted as a replicated 3 × 3 Latin square. Six ruminally cannulated cows (95 ± 26.4 DIM) were subjected to the following treatments: 240 g/cow per day each of stearic acid (SA, control), LA, or MA. Experimental periods were 28 d and cows were refaunated between periods. Lauric acid reduced protozoal counts in the rumen by 96%, as well as acetate, total VFA, and microbial N outflow from the rumen, compared with SA and MA. Ruminal methane production was not affected by treatment. Dry matter intake was reduced 35% by LA compared with SA and MA, which resulted in decreased milk yield. Milk fat content also was depressed by LA compared with SA and MA. Treatment had no effect on milk protein content. All treatments increased milk concentration of the respective treatment FA. Concentration of C12:0 was more than doubled by LA, and C14:0 was increased (45%) by MA compared with SA. Concentration of milk FA < C16 was 20% lower for LA than MA. Concentrations of trans 18:1 FA (except trans 12) and CLA isomers were increased by LA compared with SA and MA. Overall, the concentrations of saturated FA in milk fat were reduced, and that of > C16 FA and MUFA were increased, by LA compared with the other treatments. In this study, LA had profound effects on ruminal fermentation, mediated through inhibited microbial populations, and decreased DMI, milk yield, and milk fat content. Despite the significant decrease in protozoal counts, however, LA had no effect on ruminal methane production. Thus, the antimethanogenic effect of coconut oil, observed in related studies, is likely due to total FA application level, the additive effect of LA and MA, or a combination of both. Both LA and MA modified milk FA profile significantly. 相似文献
218.
Fangqing Xie Andreas Peukert Thorsten Bender Christian Obermair Florian Wertz Philipp Schmieder Thomas Schimmel 《Advanced materials (Deerfield Beach, Fla.)》2018,30(31)
The single‐atom transistor represents a quantum electronic device at room temperature, allowing the switching of an electric current by the controlled and reversible relocation of one single atom within a metallic quantum point contact. So far, the device operates by applying a small voltage to a control electrode or “gate” within the aqueous electrolyte. Here, the operation of the atomic device in the quasi‐solid state is demonstrated. Gelation of pyrogenic silica transforms the electrolyte into the quasi‐solid state, exhibiting the cohesive properties of a solid and the diffusive properties of a liquid, preventing the leakage problem and avoiding the handling of a liquid system. The electrolyte is characterized by cyclic voltammetry, conductivity measurements, and rotation viscometry. Thus, a first demonstration of the single‐atom transistor operating in the quasi‐solid‐state is given. The silver single‐atom and atomic‐scale transistors in the quasi‐solid‐state allow bistable switching between zero and quantized conductance levels, which are integer multiples of the conductance quantum G0 = 2e2/h. Source–drain currents ranging from 1 to 8 µA are applied in these experiments. Any obvious influence of the gelation of the aqueous electrolyte on the electron transport within the quantum point contact is not observed. 相似文献
219.
220.
Betul Akkopru-Akgun Daniel M. Marincel Kosuke Tsuji Thorsten J. M. Bayer Clive A. Randall Michael T. Lanagan Susan Trolier-McKinstry 《Journal of the American Ceramic Society》2021,104(10):5270-5280
Charge transport mechanisms governing DC resistance degradation in ferroelectric films are influenced by defects, particularly oxygen vacancies. This paper demonstrates that oxygen vacancies migrate in lead zirconate titanate (PZT) films under a DC bias field and contribute to resistance degradation. Model PZT thin films were developed in which the concentration and distribution of oxygen vacancies were controlled via (a) changing the dopant type and concentration from 1%–4% Mn (acceptor) to 1%–4% Nb (donor) or (b) annealing undoped PZT films at varying partial pressures of PbO. The presence of associated (immobile) and dissociated (mobile) oxygen vacancies was distinguished by thermally stimulated depolarization current (TSDC) measurements. The impact of mobile oxygen vacancies on local defect chemistry and associated charge transport mechanisms was explored by electron energy loss spectroscopy (EELS). For Mn-doped PZT films, following resistance degradation, TSDC studies revealed only one depolarization peak with an activation energy of 0.6–0.8 eV; this peak was associated with ionic space charge presumably due to migration of oxygen vacancies. The magnitude of the depolarization current peak increased with increasing degradation times. A similar depolarization current peak attributed to the existence of mobile oxygen vacancies was also observed for undoped and Nb-doped PZT films; the magnitude of this peak decreased as the Nb or PbO contents in PZT films increased. An additional TSDC peak associated with polaron hopping between Ti3+ and Ti4+ was found in both Nb-doped PZT films and undoped PZT films annealed under low PbO partial pressure. Degraded Nb-doped samples exhibited a chemical shift in the TiL2,3 peak to lower energy losses and the appearance of shoulders on the t2g and eg peaks, implying a reduction of Ti cations in regions near the cathode. 相似文献