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51.
Visible‐light‐driven photocatalytic degradation of fenpyroximate in rotating packed bed reactor using Fe3O4@PbS@Ni2P magnetic nanocomposite photocatalyst: Response surface modelling and optimization 下载免费PDF全文
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An efficient experimentally simple and inexpensive catalyst system for the selective amidation of aryl iodides using 15 mol% of CuI as catalyst, 15 mol% of L-proline as ligand and KF/Al2O3 as a base in toluene is described. 相似文献
54.
Abedinifar Fahimeh Babazadeh Rezaei Elham Biglar Mahmood Larijani Bagher Hamedifar Halleh Ansari Samira Mahdavi Mohammad 《Molecular diversity》2021,25(4):2571-2604
Molecular Diversity - Thiophene-based analogs have been fascinated by a growing number of scientists as a potential class of biologically active compounds. Furthermore, they play a vital role for... 相似文献
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Physical and chemical analysis of the polysaccharide isolated from Sargassum Terarrium (brown algae) of Karachi coast showed characteristics of the sodium alginate. Optical rotations and sulphated ash content were found and FTIR spectra showed a sharp and strong absorption band at 1600 cm?1 representing carboxylate ion which conforms high uronic acid content of the product. The viscosities of aqueous 0.1% sodium alginate solution were measured in the presence of copper II chloride (CuCl2). The viscosities were found to be increased with the increase in the concentration of electrolyte. Viscosities were also found affected with temperature. ‘A’ and ‘B’ coefficients of Jones–Dole equation were evaluated. The increase in positive values of ‘B’ coefficient with the rise of temperature led to conclusion that given electrolyte in 0.1% aqueous sodium alginate solution behaves as structure maker. Thermodynamic parameters regarding to activated state like energy of activation Eη, change in free energy of activation ΔGη and change of entropy of activation ΔSη were also evaluated. Straight-line plots of log η versus 1/T observed with positive slopes show the effect of temperature on the viscosities of solutions. Energy of activation (Eη) was found to be decreased with the rise of temperature. Change in free energy of activation (ΔGη) was also found to be increased with increase in concentrations of electrolyte and also with rise of temperature. The values of change in entropy of activation (ΔSη) were also calculated. Negative values of ΔSη were found to be increased with increase in concentration of electrolyte and also with rise of temperature. 相似文献
57.
The nanocatalyst-assisted sonodegradation of Basic Blue 41 (BB41) dye in aqueous medium was modeled and optimized using response
surface method (RSM) based on Box-Behnken design. The studied variables included pH, initial dye concentration, H2O2 concentration and sonolysis time while each factor varied at three levels: Low level (−1), Medium level (0) and High level
(+1). The ultrasound -assisted degradation was well described by developing quadratic model with correlation value squared
(R2) of 0.9114. Factor effects along with interaction effects were evaluated. The graphical optimization step was conducted to
achieve the best experimental condition in dye removal. pH, H2O2 concentration and initial dye concentration of the reaction were investigated. It was recognized that at lower pH values
the dye removal rate decreased. However, dye removal rate increased (82.5%) by increasing the concentration of H2O2 and by lowering the initial dye concentration.
相似文献
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Parvin Farshchi Seyed Khatiboleslam Sadrnezhaad Naser Moharram Nejad Mahmood Mahmoodi Leila Ibrahimi Ghavam Abadi 《Journal of nanoparticle research》2011,13(8):3511-3519
Using survey data, public awareness of and attitudes toward nanotechnology are examined in Iran (N = 759). Iran is a developing country with a national nanotechnology action plan for a ten year period starting from 2003
and has been active in the field of research and development of nanotechnology meanwhile. First, the results show that majority
of people are still not familiar with nanotechnology and perceived risks posed by this technology are not considered to be
a lot and most people feel its benefits outweigh the risks. The emotions toward this technology are of a hopeful and positive
nature and this technology is looked upon favorably in Iran. In particular, our results reveals that although the level of
trust is high specially in scientists to communicate the risks with the public, there are a great number who just have some
trust not quite a lot of it. Knowing that it is a hard and time-consuming effort to manage a nation’s view on nanotechnology,
extensive research as well as collaboration with other countries is needed to effectively communicate the risks in time. 相似文献
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Mahmood Alaghmandan Yemon Choi Ebrahim Samei 《Journal of Mathematical Analysis and Applications》2014
Let G be a restricted direct product of finite groups {Gi}i∈I, and let Z?1(G) denote the centre of its group algebra. We show that Z?1(G) is amenable if and only if Gi is abelian for all but finitely many i , and characterize the maximal ideals of Z?1(G) which have bounded approximate identities. We also study when an algebra character of Z?1(G) belongs to c0 or ?p and provide a variety of examples. 相似文献
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