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41.
Based on a Belief-Action-Outcome framework, we produced a model that shows senior managers’ perception of both the antecedents to and the consequences of Green IS adoption by a firm. This conceptual model and its associated hypotheses were empirically tested using a dataset generated from a survey of 405 organizations. The results suggest that coercive pressure influences the attitude toward Green IS adoption while mimetic pressure does not. In addition, we found that there was a significant relationship between Green IS adoption, attitude, and consideration of future consequences. Finally, we found that only long term Green IS adoption was positively related to environmental performance. 相似文献
42.
Titania porous layers with a rough surface were synthesized via micro-arc oxidation (MAO) and the effect of the applied voltage and electrolyte concentration on surface structure, and chemical composition of the layers was studied. Morphological and topographical investigations, performed by SEM and AFM, revealed that pore size and surface roughness of the layers increased with the applied voltage and the electrolyte concentration. Based on the XRD and XPS results, the grown layers consisted of anatase and rutile phases with varying fractions depending on growth conditions. It was found that anatase/rutile relative content reached its maximum value at medium applied voltages or electrolyte concentrations. Finally, hydrophilicity of the grown layers was determined using a water contact angle apparatus, and a correlation between measured contact angles and MAO-parameters was suggested. It was observed that the layers synthesized under the applied voltage of 400 V in the electrolytes with a concentration of 10 g l−1 exhibited the highest hydrophilicity. 相似文献
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Roya Jamarani Matthew W. Halloran Kushal Panchal Omar Garcia-Valdez Roozbeh Mafi James A. Nicell Richard L. Leask Milan Marić 《Polymer Engineering and Science》2021,61(4):1209-1219
Gas checks are visible fleck-shaped defects that occur on the surface of poly(vinyl chloride) (PVC) films during industrial calendering. Films containing these surface defects often do not meet minimum product specifications and therefore must be disposed of or recycled, resulting in increased cost and material waste. Currently, gas checks are controlled by keeping film gauge low and through trial-and-error modifications of processing parameters by calender operators. In this work, our group developed a series of chemical additives that can be blended with PVC to prevent the formation of gas check defects. We found that a series of poly(caprolactone) (PCL)-based compounds with diester linkers and alkyl chain cappers were all effective at preventing the formation of gas checks during calendering, with additive concentrations as low as 8 phr producing films with no gas checks. We found that the blends produced with our additives had higher melt viscosities than those produced with additives that do not remove gas checks, suggesting that viscosity plays an important role in preventing gas check defects. 相似文献
45.
Mohammad Reza Nabid Roya Sedghi Roghayeh Sharifi Hossein Abdi Oskooie Majid M. Heravi 《Iranian Polymer Journal》2013,22(2):85-92
New application of conducting polymers as stable nanocomposites for nitrate ion exchange materials in water and wastewater treatment and for environmental protection is introduced in this work. The nanocomposites of multi-walled carbon nanotubes (MWCNTs) with different polymers such as: polyaniline (PANI), polypyrrole (PPY), poly(1,8-diaminonaphthalene) [P(1,8-DAN)] and poly(2-vinylpyridine) (P2VP) were synthesized with different dopants as effective and reusable nanocomposites for nitrate removal from drinking water. Nitrate anions at toxic concentrations were removed from water using ion exchange mechanism without any toxic byproducts. The obtained results demonstrate that effective ion exchange occurs between NO3 ? and Cl?. There are some protonated heteroatoms in polymer chains that are bonded with anions of dopants and their counter ions in nanocomposites. These dopant anions on the =NH+– groups of polymers can be exchanged with NO3 ? in water. Adsorption of NO3 ? on polymer/MWCNTs nanocomposites showed dependency to some parameters. Different experimental parameters such as pH and temperature of the sample, polymers dopant, and the ratio of polymer to MWCNTs in nanocomposites affect the amount of nitrate removal. The highest removal efficiency was achieved at 1.20 g L?1 of PANI/MWCNTs (3:1) nanocomposite, pH = 6.5 and ambient temperature. After five successive cycles of nitrate removal, this parameter was still up to 70 % compared to the first run (up to 80 %). 相似文献
46.
Roya Ghafele 《Information & Communications Technology Law》2016,25(2):129-149
On the spectrum of policy formulation, the current intermediary liability regime is strongly rooted in the extreme end of policy formulation. The main focus of this policy choice is to provide an ‘enabling’ governance structure. Other options, such as providing a level playing field or exploring how and to what extent the intermediary liability regime will need to even constrain undesired digital behaviour, have hardly been given consideration. The immunities granted under the intermediary liability regime have hence successfully enabled novel business models and assured freedom of expression on the internet, leaving, however, significantly declining investment rates in music an unaddressed policy issue. According to estimates of this study, the cumulative investments lost in the UK, Germany and France alone amounted to up to nearly 4 billion Euro between 2008 and 2014. For the European Union, this situation posits a challenge with important ramifications in the long run. If Europe continues to lose out on investments in creative content, it risks losing its international competitiveness. It is thus proposed to revisit the underlying policy rationale of the intermediary liability regime and explore what steps are needed to provide a more equal level playing field for all types of market participants, be they the traditional music industry or novel forms of online intermediaries. 相似文献
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Minaee Roya Peirovi Mokhtari Mehdi Moghaddam Alireza Ebrahimi Ali Asghar Askarishahi Mohsen Afsharnia Mojtaba 《Water Resources Management》2019,33(4):1557-1569
Water Resources Management - Injection of chlorine as a disinfectant and the correct prediction of the residual amount in water distribution networks are key points and important principles in the... 相似文献
49.
High-performance biodegradable polymers have attracted considerable attention over the years because of their eco-friendly nature. The effects of processing variables on the efficiency of crosslinking, and the rheological and thermal properties of cross-linked polylactic acid (XPLA) have not been comprehensively addressed yet. In this work, XPLA was prepared through solution casting followed by curing in an oven. Enhancements in properties could be quantified in terms of structural changes in 3D structure of XPLA by varying the amount of dicumyl peroxide (DCP) as a cross--linking agent and curing temperature and time. The XPLAs were characterized by differential scanning calorimetry, thermo-gravimetric analysis, swelling, and rheological techniques. The swelling data revealed an increase in gel fraction by 1.32% per 1 °C temperature rise in the range of 125–195 °C. The results were also indicative of an increase in gel faction by 0.32% per minute in the time range of 5–100 min. Maximum variation in gel fraction occurred at 195 °C with high peroxide content. At this temperature, the variation rate of gel content was about 14.99%. With gel formation evolution, especially at 85% completion stage, the melting point was vanished. Rheological measurements showed that the Newtonian plateau disappeared for the cross-linked samples, simultaneously with the onset of shear thinning and zero-shear viscosity, through which the molecular weight obtained by the Mark–Houwink equation shifted to lower frequencies. A mathematical model based on the Charlesby–Pinner equation was developed for predicting the gel content of the XPLA as a function of curing time and peroxide concentration. The Flory–Huggins parameter also changed during the cross-linking process as a function of cross-linking density. This study is focused on adjusting cross-linking density and processing factors, like temperature and time, to achieve an XPLA with desirable properties. 相似文献
50.
Amit Chaudhry 《微纳电子技术》2011,48(6):357-364
研发了一种通过MOSFET的超薄栅氧化物分析直接隧穿电流密度的模型。采用Wentzel-Kramers-Brilliouin(WKB)近似计算了隧穿概率,利用清晰的表面势方程改进模型的准确性。在研究模型中考虑了Si衬底中反型层的量子化和多晶硅栅耗尽,还研究了多晶硅掺杂对栅氧化层隧穿电流的影响。仿真结果表明,栅氧化层隧穿电流随多晶硅栅掺杂浓度的增加而增加。该结论与已报道的结果相吻合,从而证明了该模型的正确性。 相似文献