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231.
232.
A novel donor–acceptor type conducting polymer based on BODIPY dye as acceptor and EDOT units as donor parts is synthesized electrochemically. The unique combination of BODIPY and EDOT units provides an ambipolar (n- and p-doping processes) low band gap material (4). This is the first example of p–n junction in an organic π-conjugated material where BODIPY unit is incorporated directly in the main chain. Furthermore, the polymer film exhibits electrochromic behavior upon p-doping: a color change from light violet (neutral) to indigo (oxidized). 相似文献
233.
A novel conducting polymer was successfully synthesized via electropolymerization of 1-(1H-pyrrol-1-yl)-2,5-di(thiophen-2-yl)-1H-pyrrole. The electrochemical and electro-optical properties of the corresponding polymer, which was the first example of polymer containing 1,1′-bipyrrole units, were elaborated using electroanalytical and spectroscopic techniques. Cyclic voltammograms and electro-optical studies showed that the polymer has a stable and well-defined reversible redox process as well as electrochromic behavior. The processable polymer film also possessed a yellowish orange light emitter property. 相似文献
234.
Hoefling Atilla; Likowski Katja U.; Deutsch Roland; H?fner Michael; Seibt Beate; Mühlberger Andreas; Weyers Peter; Strack Fritz 《Canadian Metallurgical Quarterly》2009,9(1):50
The main purpose of this study was to examine if disgust toward unpalatable foods would be reduced among food-deprived subjects and if this attenuation would occur automatically even under moderate levels of food deprivation. Subjects were either satiated or food deprived for 15 hours and electromyographic activity was recorded at the levator muscle region while they were watching pictures of palatable versus unpalatable foods, and pictures of positive versus disgust-related control pictures. For control purposes, subjects' activity of the zygomaticus and corrugator muscles was also recorded. As compared with satiated subjects, food-deprived subjects exhibited stronger activity in the zygomaticus muscle region when watching pictures of palatable foods (but not when watching positive control pictures). More important, hungry subjects exhibited weaker activity in the levator muscle region when watching pictures of unpalatable foods (but not when watching disgusting control pictures). Thus, this is the first study ever to show that specific emotions (disgust) are moderated by homeostatic dysregulation automatically. Results indicate that the modulation of facial expressions might play an important role in lowering the threshold for food intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
235.
New compounds consisting of aniline units linked by polyether bridges have been synthesized and their electrochemical polymerization was performed via constant potential electrolysis and cyclic voltammetry in an aqueous solution containing 3.0 mol L?1 H2SO4. Chemical polymerization was carried out using (NH4)2S2O8 as oxidizing agent. It was found that both methods gave the same polymer product without any cleavage of the polyether bridge between aniline rings. The polymers were characterized using the Fourier transform infrared spectroscopic technique and the thermal behavior of electrochemically prepared polymers was investigated using thermogravimetric analysis. Spectroelectrochemical properties of the films were investigated using the in situ UV‐visible spectroscopic technique. Copyright © 2007 Society of Chemical Industry 相似文献
236.
Video games in psychotherapy. 总被引:1,自引:0,他引:1
Video games have found their way into the clinical care of youth in most medical fields, and academic interest in their use is increasing steadily. The popularity of video games among youth may qualify them as a useful tool in psychotherapy for children and adolescents. Limited literature on use of video games in mental health care suggests that they can help young patients become more cooperative and enthusiastic about psychotherapy. Recent experience suggests that video games may facilitate therapeutic relationships, complement the psychological assessment of youth by evaluating cognitive skills, and elaborate and clarify conflicts during the therapy process. Concerns about video game content, perceived effects on youth, and lack of familiarity with this medium may form a barrier in their use in therapy offices. Further research on the benefits of video game use in psychotherapy, including patient characteristics that may moderate outcomes, is needed. Finally, future collaborations between clinicians and video game developers may produce specific games to be used in psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
237.
Behaviour of masonry structures under earthquake loading. The objective of the seismic design of structures is to provide sufficient resistance considering the ductility of the structure. With experiments on storey‐high walls at the University of Dortmund the performance of masonry shear walls under simulated earthquake loading was identified up to failure. The nonlinear behaviour of the walls was evaluated with regard to resistance and potential for ductility. Depending on the type of the limit state the walls exhibited different quantities of ductility. Analyses showed that within certain limits mechanisms with higher ductility can be attained by appropriate tuning of the structural parameters. Considering configurations of walls typical for terraced houses and apartment buildings the structural ductility and the corresponding behaviour factors for seismic design (see EC 8 and DIN 4149) were assessed. 相似文献
238.
It has been shown that in the context of a linear theory for a floating body with six degrees of freedom each of the 6× 6 added-mass and damping matrices contains three distinct Cartesian second-order tensors in regard to translational, rotational and interaction between translational and rotational oscillations. As a result of this, a new technique based on the transformation law of second-order tensors is introduced for motion analysis of offshore platforms which can be used as an alternative to the common methods in offshore engineering. 相似文献
239.
The management of resources has been claimed to be as important as scheduling methods. Inefficiency in managing resources may bring about severe delays and cost overruns caused by resource shortages in some cases and/or idle resources in others. Therefore, resources should be utilized efficiently to prevent project failures. Resource leveling is one of the approaches that are used for the management of resources. It aims to minimize fluctuations, peaks, and valleys in resource utilization without changing the completion time of a project and the number of resources required. Although the main principle behind traditional resource leveling is achieving an even flow of resources while the original project duration remains unchanged, the literature supports the need to develop an efficient model that discriminates among the activities that are selected for participation in resource leveling. For this purpose, this study has developed a model that considers the float consumption rates of activities in resource leveling. The float consumption rate is the percentage that is set to determine the maximum amount of float which will be consumed to shift the start time of the activity. The proposed model allows a scheduler to assign float consumption rates to each activity that can be used during the resource leveling procedure. When the required information is inputted, the proposed model automatically changes the required daily resources as it shifts the noncritical activities along their available total float times. The proposed model is expected to minimize the likelihood of severe delays and cost overruns. The model is demonstrated by constructing a network and its resource utilization histograms. 相似文献
240.
Y. G. Devrim 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2013,35(3):238-246
Abstract Pyrolysis kinetics of the Yeni Çeltek lignite/sugar beet pulp blends prepared at different ratios (100:0, 80:20, 60:40, 40:60, 20:80, and 0:100) were investigated by thermogravimetric analysis in the present study. All the experiments were carried out in nitrogen atmosphere under non-isothermal conditions with a heating rate range of 30 K/min in the pyrolysis temperature interval of 298–1,173 K. The Arrhenius model is applied to determine the kinetic parameters from TG/DTG curves. Apparent activation energies of the lignite and sugar beet pulp were calculated as 51.55 kJ/mol and 97.27 kJ/mol, respectively. Activation energies of the blends were also calculated and were found to vary between 54.87 and 74.83 kJ/mol. Effects of blending ratio of lignite to sugar beet pulp on kinetic parameters were investigated and the results were discussed. 相似文献