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141.
Michal Firstenberg Kammasandra Nanjunda Shivananda Irit Cohen Olga Solomeshch Vladislav Medvedev Nir Tessler Yoav Eichen 《Advanced functional materials》2011,21(4):634-643
Sequence‐independent or “click”‐type chemistry is applied for the preparation of novel π‐conjugated oligomers. A variety of bi‐functional monomers for Wittig–Horner olefination are developed and applied in a sequential protection–deprotection process for the preparation of structurally similar π‐conjugated oligomers. Selected oligomers are incorporated as the organic semiconductors in light‐emitting diodes and a field‐effect transistor, demonstrating the potential of the approach. 相似文献
142.
K. N. Vdovin A. E. Pozin I. E. Petrov A. A. Podosyan V. V. Tochilkin 《Steel in Translation》2013,43(7):452-454
The wear topography of the copper mold walls in continuous slab-casting machines at OAO MMK is studied. The results confirm theoretical ideas regarding the interaction of an extended slab and the mold walls. 相似文献
143.
S. V. Gutenko S. A. Petrov Yu. A. Fedonin P. V. Kupriyanov A. V. Androsov 《Journal of Communications Technology and Electronics》2018,63(3):235-238
The possibility of expanding the dynamic range of microwave receivers used in passive radar due to circuit specificities of the input linear circuits is considered. Engineering calculations and graphic dependences of the dynamic range as well as an example of constructive implementation and the results of measuring the main parameters are presented. The conclusion is made on the feasibility and expediency of using in microwave receivers with an extended dynamic range of input linear circuits with disableable amplification stages. 相似文献
144.
The regularities of changes in the properties of the electrical response of reinforced concrete to an impact action in a four-point bending flexural test and the influence of the rebar cage configuration on the processes of failure in reinforced beams and on electrical response parameters have been studied. Criteria have been proposed for determining the stages of failure in reinforced concrete beams, based on electrical response parameters. The nucleation and growth of macrocracks in the tensile zones of reinforced beams is accompanied by a drop in the maximum cross-correlation coefficient of signal spectra at the current and previous loading levels to 0.45–0.6. An increase in the energy attenuation coefficient of electrical responses in a reinforced beam by 1.5–2.5 times can serve as a precursor to its impending catastrophic breakdown. 相似文献
145.
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147.
Andrew Yakimov Victor Kirienko Vladislav Armbrister Anatolii Dvurechenskii 《Nanoscale research letters》2013,8(1):217
We report the fabrication and characterization of a ten-period Ge quantum dot photodetector grown on SiGe pseudosubstrate. The detector exhibits tunable photoresponse in both 3- to 5- μm and 8- to 12- μm spectral regions with responsivity values up to about 1 mA/W at a bias of −3 V and operates under normal incidence radiation with background limited performance at 100 K. The relative response in the mid- and long-wave atmospheric windows could be controlled through the applied voltage. 相似文献
148.
The paper presents several sorting methods of γ-ray events which were implemented in the data acquisition, processing and visualization system, developed at the Institute of Physics of the Slovak Academy of Sciences. The sorting methods using various shapes of gates (conditions) are presented, including rectangular windows, polygons, gates defined by arithmetic functions, spherical, ellipsoidal and composed gates. The examples illustrating the use of these methods are presented as well. 相似文献
149.
The experimental data on the normally hemispherical reflectivity of zirconium oxide ceramics are obtained for the wavelength of 0.63 m in the course of the first cycle of heating by concentrated laser radiation up to temperatures above the melting point and free cooling in ambient air. The obtained data are compared with analogous results of the second and subsequent cycles of heating and cooling. Analysis is made of the effect of the temperature field in the heated layer on the reflectivity and on the effective temperature measured by a pyrometer. 相似文献
150.
Nizhnikov Michael E.; Varlinskaya Elena I.; Petrov Evgeniy S.; Spear Norman E. 《Canadian Metallurgical Quarterly》2006,120(2):267
Toward understanding why infant rats ingest high levels of ethanol without initiation procedures, the authors tested effects of mu and kappa receptor antagonists on ethanol reinforcement in neonatal rats. After an intracisternal injection of CTOP (mu antagonist), nor-Binaltorphimine (kappa antagonist), or saline, newborn (3-hr-old) rats were given conditioning pairings of an odor with intraorally infused ethanol or a surrogate nipple with ethanol administered intraperitoneally (to minimize ethanol's gustatory attributes). In each case, these opioid antagonists reduced or eliminated ethanol's reinforcement effect. The same effects occurred with saccharin as the reinforcer in olfactory conditioning. The results imply that activation of mu and kappa receptors, apparently acting jointly, is necessary for reinforcement or that antagonists of this activity impair basic conditioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献