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81.
Pearsall Matthew J.; Christian Michael S.; Ellis Aleksander P. J. 《Canadian Metallurgical Quarterly》2010,95(1):183
The primary purpose in this study was to extend theory and research regarding the motivational process in teams by examining the effects of hybrid rewards on team performance. Further, to better understand the underlying team level mechanisms, the authors examined whether the hypothesized benefits of hybrid over shared and individual rewards were due to increased information allocation and reduced social loafing. Results from 90 teams working on a command-and-control simulation supported the hypotheses. Hybrid rewards led to higher levels of team performance than did individual and shared rewards; these effects were due to improvements in information allocation and reductions in social loafing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
83.
Rawashdeh Majdi Shorfuzzaman Mohammad Artoli Abdel Monim Shamim Hossain M. Ghoneim Ahmed 《Multimedia Tools and Applications》2017,76(20):21157-21170
Multimedia Tools and Applications - Massive amounts of data are available on social websites, therefore finding the suitable item is a challenging issue. According to recent social statistics, we... 相似文献
84.
Maria N. Timofeeva Maxim S. Melgunov Oxana A. Kholdeeva Mikhail E. Malyshev Aleksander N. Shmakov Vladimir B. Fenelonov 《Applied catalysis. B, Environmental》2007,75(3-4):290-297
Iron-containing mesoporous mesophase materials Fe-MMM-2 have been synthesized by a sol–mesophase route under mild acidic conditions and characterized by DRS-UV–vis, XRD, and N2 adsorption measurements. It was found that pH of the synthesis solution and iron content in the samples affect both the textural characteristics and the state of iron atoms. Isolated iron species predominate in silica framework under Fe < 2 wt% and pH 1.0 or Fe 1 wt% and pH < 2.0. These species are stable to leaching and highly active in full H2O2-based phenol oxidation. The increase in iron loading and pH of the synthesis solution lead to the agglomeration and formation of oligomeric iron species, which, in turn, results in the reduction of the catalytic activity of Fe-MMM-2 and the increase of iron leaching. 相似文献
85.
Mariusz Chalecki Wojciech Czaplejewicz Aleksander Pawłuszewicz 《Welding International》2013,27(3):165-169
The aim of this research was to develop a process for welding BORON 27 type quenched steel, manufactured in Finland. The composition of a shielding gas mixture was selected by means of trials: 90% Ar, 5% CO2, and 5% O2. Joints were reproduced by this method, i.e. welded, quenched joints as well as unquenched welded joints, and were tested for quality. Tests included X-ray radiography, macroscopic testing, hardness tests, and tearing and bending resistance tests. The results of these tests were presented in the article. 相似文献
86.
Effect of different concentration of rapeseed‐oil‐based polyol and water on structure and mechanical properties of flexible polyurethane foams 下载免费PDF全文
Flexible polyurethane foams (FPURFs) with varied concentration of water from 3.2 to 4.2% and rapeseed oil based polyol (ROP) in the range of 13–22% in polyol premix were obtained. Effects of changes in polyurethane (PUR) formulation on the foaming process and mechanical properties of FPURFs were analyzed. It was found that the change of water content in PUR formulation influences its foaming process. Higher water content in the PUR formulation increases the growth velocity and the temperature of reaction mixture. In the case of foams modified with ROP, an opposite effect can be observed, where higher content of that component resulted in overall downturn of the foaming process and decreases of registered temperature inside the foams core. An addition of ROP beneficially influences on foams cellular structure favoring creation of finer cells. Such modification of PUR formulation with ROP increased apparent density, reduced hardness, and resilience of flexible foams. What is more the support factor of FPURFs with ROP was higher in comparison to the reference foam. Along with higher water content in the PUR formulation, apparent density and hardness has decreased and foams ability to absorb energy has been increased. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42372. 相似文献
87.
DMSO Chemically Alters Cell Membranes to Slow Exocytosis and Increase the Fraction of Partial Transmitter Released 下载免费PDF全文
Dr. Soodabeh Majdi Neda Najafinobar Johan Dunevall Jelena Lovric Prof. Andrew G. Ewing 《Chembiochem : a European journal of chemical biology》2017,18(19):1898-1902
Dimethyl sulfoxide (DMSO) is frequently used as a solvent in biological studies and as a vehicle for drug therapy; but the side effects of DMSO, especially on the cell environment, are not well understood, and controls with DMSO are not neutral at higher concentrations. Herein, electrochemical measurement techniques are applied to show that DMSO increases exocytotic neurotransmitter release, while leaving vesicular contents unchanged. In addition, the kinetics of release from DMSO‐treated cells are faster than that of untreated ones. The results suggest that DMSO has a significant influence on the chemistry of the cell membrane, leading to alteration of exocytosis. A speculative chemical mechanism of the effect on the fusion pore during exocytosis is presented. 相似文献
88.
Nina Daneu Aleksander Renik Slavko Bernik Drago Kolar 《Journal of the American Ceramic Society》2000,83(12):3165-3171
The effects of adding small quantities of SnO2 to the basic ZnO–Bi2 O3 varistor composition were studied in terms of phase reactions, microstructural development, and the formation of inversion boundaries. Scanning and transmission electron microscopy studies showed that the inversion boundaries, triggered by the addition of SnO2 , cause anisotropic grain growth in the early stages of sintering. ZnO grains that include inversion boundaries grow exaggeratedly, at the expense of normal grains, until they dominate the microstructure. Higher additions of SnO2 lead to an increase in number of grains with inversion boundaries and to a more fine-grained microstructure. The increasing amount of secondary phases is also related to a higher level of SnO2 addition; however, the influence of these phases on ZnO grain growth is subordinate to the role of inversion boundaries. 相似文献
89.
Tanja Vrabelj Aleksander Matavž Hana Uršič Vid Bobnar Barbara Malič 《Journal of the European Ceramic Society》2019,39(7):2325-2330
Sodium niobate thin films doped with manganese (NN), and NN films modified with 5 or 10 mol % calcium zirconate (CZ) on platinized silicon substrates were prepared by chemical solution deposition. The 250-nm-thick films crystallize in a perovskite phase with fine, equiaxed grains. The NN films exhibit well-shaped ferroelectric loops with a remanent polarization and coercive field of ~10 μC/cm2 and ~100 kV/cm, respectively. The modification with CZ strongly influences the ferroelectric response of the films: the remanent polarization progressively decreases to around 2.5 μC/cm2. The absence of an anti-ferroelectric response, which has previously been confirmed in bulk NN-CZ ceramics, is attributed to the nanoscale microstructure and residual thermal stresses. All the studied films exhibit a piezoelectric response with the highest piezoelectric d33 coefficient of 35 pm/V at 300 kV/cm bias field for the NN modified films with 5 mol % CZ, making them candidates for lead-free piezoelectric thin-film applications. 相似文献
90.
Two rapeseed-oil-based polyols were synthesized by partial epoxidation of the double bonds in fatty acid chains and overall opening oxirane rings by using diethylene glycol. Flexible polyurethane foams with varied isocyanate index and modified by partial substitution of petrochemical polyether triol with rapeseed-oil-derived polyols were obtained. Bio-polyols: Polyol I and Polyol II differed in functionalities (2.5 and 5.2, respectively) and hydroxyl values (114 and 196 mg KOH/g, respectively). Influence of the bio-polyols on mechanical properties, resilience, apparent density, and cellular structure of synthesized foams was investigated. Compression properties were examined and compared via determining compression values and compression stress—strain characteristics, as well as tensile strength and elongation at break were estimated. Foams modified with Polyol I had higher values of resilience and elongation at break than those with Polyol II, while higher tensile and compression strength and superior cell structure were observed in the case of foams modified with Polyol II. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献