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151.
Sajjad Keshipour Nastaran Kalam Khalteh 《Journal of the Iranian Chemical Society》2016,13(11):1977-1982
A new support for Pd(II) was synthesized via the functionalization of Fe3O4 nanoparticles with N-(2-aminoethyl)acetamide. PdCl2 was anchored to the support for obtaining a heterogeneous magnetically recoverable catalyst for Pd(II). High yield and excellent selectivity were obtained for the green epoxidation of styrene derivatives using H2O2 as a green oxidant in H2O as the solvent at 100 °C. Also, the recovered catalyst is applicable for four times without significant decrease in yield. 相似文献
152.
Farhat Ullah Abdul Sadiq Abid Hussain Sajjad Ahmad Muhammad Imran 《Natural product research》2016,30(12):1440-1444
This study was designed to investigate antioxidant and anticholinesterase potential of Iris germanica var; florentina. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential of plant samples were investigated by Ellman’s assay. Antioxidant activity was performed using DPPH, H2O2 and ABTS free radical scavenging assays. Total phenolics and flavonoids contents were expressed in mg GAE/g dry weight and mg RTE/g, respectively. In AChE inhibition assay, Ig.Fl, Ig.Sp and Ig.Cf fractions exhibited highest activity with IC50 values of < 0.1, 5.64 and 19 μg/mL, respectively. In BChE inhibitory assay, Ig.Fl, Ig.Sp, Ig.Cf and Ig.Cr were most active with IC50 of < 0.1, < 0.1, 31 and 78 μg/mL, respectively. In DPPH assay, Ig.Fl and Ig.Cf exhibited highest inhibition of free radicals, 80.52% (IC50 = 9 μg/mL) and 78.30% (IC50 = 8 μg/mL), respectively. In ABTS assay Ig.Cr, Ig.Cf, Ig.Fl and Ig.Sp exhibited IC50 values of < 0.1, 2, 2 and 3 μg/mL, respectively. 相似文献
153.
Optimal economic load dispatch based on wind energy and risk constrains through an intelligent algorithm 下载免费PDF全文
This article focus on optimal economic load dispatch based on an intelligent method of shark smell optimization (SSO). In this problem, the risk constrains has been considered which has root in uncertainity and unpredictable behavior of wind power. Regarding to increasing of this clean energy in power systems and un‐dispatchable behavior of wind power, its conditional value at risk index considered in this article which consists of loss from load and "spilling" wind energy connected with unpredictable imbalances among generation and load. This problem has been considered as an optimization problem based on SSO that evaluate the balance between cost and risk. This algorithm is based on distinct shark smell abilities for localizing the prey. In sharks' movement, the concentration of the odor is an important factor to guide the shark to the prey. In other words, the shark moves in the way with higher odor concentration. This characteristic is used in the proposed SSO algorithm to find the solution of an optimization problem. Effectiveness of the proposed method has been applied over 30‐bus power system in comparison with other techniques. © 2016 Wiley Periodicals, Inc. Complexity 21: 494–506, 2016 相似文献
154.
Ethylene polymerization was carried out by using a group of new dizirconium(IV) tetrapyrrole complexes as catalysts and MAO as co-catalyst under 1 atmosphere pressure of ethylene gas at 25 and 40°C. The highest value of catalyst activity was obtained
at 40°C by using bizirconium complexes including one calix[4]pyrrole between two zirconium centers and two terminal chlorines,
while zirconium(IV) complexes with coordinated THF, almost have not catalytic activity. The maximum catalytic activity mounted to 830 kg/mol·bar·h by Zr2(Cy4
Pyr
4)Cl4. The results show that the structure of the coordination sphere of zirconium(IV) has great influence on the rate of polymerization,
molar masses of forming polymer, and its molecular mass distribution.
Correspondence: Sajjad Mohebbi, Chemistry Department, University of Kurdistan, P.O. Box 66176-416, Sanandaj, Iran. 相似文献
155.
Photocatalytic activity of TiO2 nanoparticles in the visible light region was enhanced. TiO2–CdSe and TiO2–CdSe/CdS nanohybrids were supported on the reduced graphene oxide. These nanohybrid materials were applied as photocatalyst toward oxidation of aromatic alcohols under a mild condition and the molecular oxygen as oxidant. A plausible mechanism for the photocatalytic oxidation was also proposed. Desired nanohybrids were obtained via in situ fixation of CdSe/CdS on the surface of nanosheets of reduced graphene oxide (rGO). Finally, it was modified by TiO2 sol nanoparticles through a hydrothermal method. The obtained nanomaterials, were characterized by SEM, TEM imaging, XRD, EDAX, DRS and XPS analyses. The size of nanohybrids materials were distributed mostly in a narrow range of 50–65 and 60–75 nm for TiO2–rGO–CdSe and TiO2–rGO–CdSe/CdS, respectively. These photocatalysts showed high catalytic activity under visible light irradiation in a short reaction time and even higher selectivity rather than UV irradiation. The yield of catalytic oxidation increased at least 25–30% for TiO2–CdSe/CdS on rGO, which could be related to its higher light sensitivity and lower energy band gap. The photocatalysts were recycled and reused 8 times without significant loss of their activities due to their stability under visible light. 相似文献
156.
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159.
Ali Ghaffari 《数学学报(英文版)》2008,24(7):1089-1096
In this paper, among other things, the author studies the weak^*-closed left translation invariant complemented subspace of semigroup algebras and group algebras. Also, the author studies the relationships between projections and amenability. 相似文献
160.