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11.
Rasa Kazakevičiūtė‐Makovska Safa Mogharebi Holger Steeb Gunther Eggeler Klaus Neuking 《Advanced Engineering Materials》2013,15(8):732-739
Experimental study of temperature‐ and frequency‐dependent properties of the commercially available shape memory polymer Tecoflex? EG 72D (TFX) (Lubrizol, USA) using dynamic mechanical analysis (DMA) technique is presented. Temperature scan DMA tests have been carried out in three distinct deformation modes, uniaxial tension, three‐point bending, and simple torsion, using two different testing rigs at different test parameters (frequency, strain amplitude, and heating rate) in temperatures ranging from below to above the glass transition temperature. The influence of different test parameters and some discrepancies in the temperature‐dependent storage and loss moduli (and hence the loss factor) measured by DMA in different deformation modes are discussed. 相似文献
12.
J. Požela K. Požeal A. Šilėnas V. Jasutis L. Dapkus A. Kinduris V. Jucienė 《Semiconductors》2002,36(1):116-120
The current response of AlxGa1−x
As graded-gap layers to optical and X-ray radiation was studied. A graded-gap electric field in the 15-μm-thick AlxGa1−x
As layers, with x varying from 0 to 0.4, ensures the complete collection of charges generated by ionizing radiation and makes it possible to
attain the value of 0.25 A/W for the current-power sensitivity of AlxGa1−x
As. In the layers with a lowered doping level of the narrow-gap region of the graded-gap AlxGa1−x
As layer, the voltage-power sensitivity to X-ray radiation with energy lower than 15 keV is as high as 1.6×103 V/W in the photovoltaic mode.
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Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 36, No. 1, 2002, pp. 124–128.
Original Russian Text Copyright ? 2002 by J. Požela, K. Požela, Šilėnas, Jasutis, Dapkus, Kinduris, Jucienė. 相似文献
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A. Balčiūnaitė Z. Sukackienė K. Antanavičiūtė J. Vaičiūnienė A. Naujokaitis L. Tamašauskaitė-Tamašiūnaitė E. Norkus 《International Journal of Hydrogen Energy》2021,46(2):1989-1996
Effective Co/Cu, CoB/Cu, and CoBM (M = Mo,Zn,Fe)/Cu catalysts were prepared on the copper surface by a simple electroless deposition method using a morpholine borane as a reducing agent in the glycine solution. The activity of the deposited catalysts was investigated for hydrogen generation from an alkaline sodium borohydride solution. It was determined that these synthesized catalysts demonstrated the catalytic activity for the hydrolysis reaction of NaBH4. The lowest obtained activation energy (EA) of the hydrolysis reaction of NaBH4was 27 kJ mol?1 for the CoBMo/Cu catalyst. The hydrogen generation rate of 15.30 ml min?1 was achieved using CoBMo/Cu catalysts at 313 K and it increased ~3.5 times with the increase of temperature to 343 K. The highest hydrogen generation rate obtained by CoBMo/Cu films may be related to the hierarchical cauliflower-shaped 3D structures and the high roughness surface area. Moreover, the CoBMo/Cu catalyst showed an excellent reusability. 相似文献
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Scientometrics - The concept of Earth system science denotes a shift in the scientific discourse from disciplinary accounts of isolated components of the global environment towards the holistic and... 相似文献
18.
Genetic diversity of phalaris arundinacea populations in relation to river regulation in the Merkys basin,Lithuania
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N. O. Anderson L. Jocienė E. Krokaitė T. Rekašius A. Paulauskas E. Kupčinskienė 《河流研究与利用》2018,34(4):300-309
During the 1950s–1960s, the Merkys river basin, the largest protected area of Lithuania, underwent severe anthropogenic regulations. Within the Baltic States, the genetic diversity of Phalaris arundinacea populations is unknown and how they might be affected by anthropogenic activities such as river regulation. The objectives of this study were to compare molecular parameters (SSRs or microsatellite loci) within and among populations from natural river fragments with populations from regulated river parts. Study populations have greater genetic diversity within, rather than among, populations. The upstream portion of the Merkys basin populations had lower genetic diversity compared with further downstream. The mean number of polymorphic SSR loci was lower for populations from regulated parts of the river basin compared with natural ones. Main principle coordinate analysis revealed populations of regulated rivers at marginal positions. Bayesian clustering showed that current populations are admixtures of 3 distinct genetic groups, based on STRUCTURE analysis (K = 3 groupings) in geographic subdivisions of (a) downstream populations (Var?n?, Verseka, Upper Grūda, Lower Grūda, Upper Merkys, Lower Merkys), (b) upstream populations (Upper ?al?ia, Ber??, Lower ?al?ia, Visin?ia, Lower ?altyk??ia, Nedil?), and (c) the 2 regulated sites in the distinct geographic area of Taurupis and Upper ?altyk??ia. P. arundinacea in the Merkys river basin does not all belong to a single, random‐mating population encompassing its tributaries or among populations across its geographic scales. In several instances, river regulation might impair the genetic diversity of P. arundinacea populations. 相似文献
19.
Daiva Leskauskaite Ina Jasutiene Ernesta Malinauskyte Milda Kersiene Paulius Matusevicius 《International Journal of Dairy Technology》2016,69(2):177-183
The purpose of this study was to analyse emulsions for vitamin D3 delivery in yoghurt and sour cream. Oil‐in‐water emulsions stabilised by whey proteins alone and by whey proteins plus carboxymethylcellulose were used. No change in vitamin D3 added to the yoghurt and sour cream in the form of both emulsions was observed after storage at 7 days in light and 14 days in dark at 4 °C. The results of bioavailability tests, using rats, for vitamin D3 from the fortified emulsions and yoghurt indicated that it is feasible to use stabilised emulsions as delivery systems of vitamin D3 in fortified products. 相似文献
20.
Vidmantas Dikinis Violeta Rėzaitė Irina Demčenko Algirdas Seiskis Tauras Bernatavičius 《金属精饰学会汇刊》2013,91(3-4):98-104
The influence of the components of an acidic solution: Cr(III) nitrate-malonic acid-Co(II) salt and treatment conditions on zinc dissolution and formation of Chromate films as well as on their decorative and protective properties have been studied using the analytical, XPS, structural and accelerated corrosion test methods. An organic acid is the main component, which has an essential influence on zinc dissolution and formation of Chromate films as well as their decorative and protective properties. The influence of organic acid is directly related with the state of the Cr3+ ions in chromating solution. When the Cr3+ ions are in the form of hexaaquaions, the organic acid increases the quantities of the zinc dissolved and the Cr(III) deposited on the zinc surface (especially at 60°C). It also predetermines the formation of a thick, porous Chromate film with large cracks at 60°C. Its decorative and protective properties are rather poor. When Cr3+ ions are in the form of a complex with organic acid, the quantities of the zinc dissolved and the Cr(III) deposited on the zinc surface significantly decrease and thinner Chromate films with an even surface, good decorative appearance and high corrosion resistance are formed Decorative blue-bright Cr(VI)-free films with a slight iridescent tint, obtained in solution, containing Cr(III) nitrate (0.2), malonic acid (0.3) and Co(II) nitrate (0.02) mol dm?3, at p H 1.6-2.0 at room temperature over 30–60 s, possess corrosion resistance (192–240 h in a salt spray chamber) similar to that of iridescent Chromate films, obtained in acidic Cr(VI) solution. 相似文献