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排序方式: 共有1723条查询结果,搜索用时 15 毫秒
981.
Mohammad Akbari Mostafa Farajpour Mostafa Aalifar Mohammad Sadat Hosseini 《Natural product research》2018,32(3):322-326
The effects of gamma irradiation (GR) on total phenol, anthocyanin and antioxidant activity were investigated in three different Persian pistachio nuts at doses of 0, 1, 2 and 4 kGy. The antioxidant activity, as determined by FRAP and DPPH methods, revealed a significant increase in the 1–2 kGy dose range. Total phenol content (TPC) revealed a similar pattern or increase in this range. However, when radiation was increased to 4 kGy, TPC in all genotypes decreased. A radiation dose of 1 kGy had no significant effect on anthocyanin content of Kale-Ghouchi (K) and Akbari (A) genotypes, while it significantly increased the anthocyanin content in the Ghazvini (G) genotype. In addition, increasing the radiation to 4 kGy significantly increased the anthocyanin content of K and G genotypes. To conclude, irradiation could increase the phenolic content, anthocyanin and antioxidant activity of pistachio nuts. 相似文献
982.
Ahmadi Mostafa Rashedi Reza Ahmadjo Saeid Karimi Mahsa Zahmaty Majid Mortazavi Seyed Mohammad Mahdi 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2523-2533
Journal of Thermal Analysis and Calorimetry - Development of olefin block copolymers (OBCs) based on new catalytic systems is challenging. We evaluate the performance of rac-ethylenebis(1-η... 相似文献
983.
M. S. Mostafa M. M. Wakkad A. Gaber N. Afify 《Journal of Thermal Analysis and Calorimetry》1995,45(6):1525-1531
The thermophysical properties (thermal diffusivitya, specific heatC p and thermal conductivity λ), of Bi1.5Sb0.5Te3 were measured in the temperature range 300–700 K. The results showed that the contribution of the charge carriers to the thermal conduction is negligibly small in comparison with the contribution of phonons at high temperatures. On the other hand, the heat conduction due to the simultaneous thermal diffusion of electrons and holes is important as well as the lattice thermal conduction. The explanation of the results was supported by using electrical conductivity measurements and X-ray diffraction. 相似文献
984.
Hossein Rezaei 《Journal of Dispersion Science and Technology》2016,37(7):969-979
The aim of this work was to apply dissipative particle dynamics (DPD) mesoscopic simulations to study the interfacial orientation and the effect of the nonionic surfactant, hexaethylene glycol monododecyl ether (C12E6), on different (oil (dodecane)/water) microemulsion systems. The Hildebrand-solubility-parameter model and Flory–Huggins/Hansen-solubility-parameter (FH/HSP) model were combined to evaluate the DPD interaction parameter (aij) where the solubility parameters (δi) as DPD input parameters were preliminary validated by all-atom molecular dynamics (MD) results and experimental data. The interfacial property dependence of dodecane/water/C12E6 system on the oil/water (o/w) ratio and on the concentration of surfactant and orientation at the interface were investigated. It was found that the surfactant addition reduced the IFT of o/w interfaces and this reduction was more efficient for water-in-oil microemulsions (o/w ≤ 1). 相似文献
985.
Ali Shirzadmehr Mosayeb Rezaei Hasan Bagheri Hosein Khoshsafar 《International journal of environmental analytical chemistry》2016,96(10):929-944
In this research, a new strategy for construction of a development potentiometric carbon paste Zn2+-ion selective electrode based on a novel nano-sensing layer is suggested. The proposed nano-sensing layer was prepared with the addition of a synthesised Zn2+-ion imprinted polymer nanoparticles ‘as an efficient sensing agent’ into the carbon paste matrix consisting of graphite powder, nanographene-composite ‘graphene nanosheets decorated with silver nanoparticles’ and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ‘ an ionic liquid ’, as the conducting binder. Under the optimised experimental conditions, the suggested nanographene-composite potentiometric sensor presented a low detection limit of 1.93 × 10?1 μg L?1 and a linear analytical range from 2.62 × 10?1 to 6.54 × 105 μg L?1 with an excellent Nernstian slope of 29.80 mV decade?1. The proposed zinc selective sensor was successfully applied for the highly sensitive determination of trace amounts of Zn2+ in environmental and biological samples with satisfactory results. 相似文献
986.
Mostafa I. Abdelglil Sanaa O. Abdallah Mohamed A. El-Desouky Mohammad Y. Alfaifi Serag Eldin I. Elbehairi Aly F. Mohamed 《Molecules (Basel, Switzerland)》2021,26(22)
We aimed to evaluate the anticancer potential of crude venom (CV), γ irradiated Certastes cerastes venom (IRRV), and propolis ethanolic extract (PEE). IRRV showed a higher toxicity than CV, while CV-PEE showed higher toxicity than IRRV and CV against lung [A549] and prostate [PC3] cancer cells. Toxicity to [A549] and [PC3] cells was concentration and cell type dependent. In comparison to controls, apoptotic genes showed a significant upregulation of P53 and Casp-3 and a downregulation of Bcl-2. Also, induced elevated DNA accumulation in the [S] phase post PC3 cell treatment with IRRV and CV, as well as a significant DNA accumulation at G2/M phase after IRRV treatment of A549 cells. In contrast, PC3 cells showed a negligible cellular DNA accumulation after PEE treatment. Glutathione reductase [GR] was reduced in case of PC3 and A549 cell treated with IRRV, CV, and PEE compared with its values in untreated cell control. The Malondialdehyde [MDA] values in both cells recorded a significant elevation post IRRV treatment compared to the rest of the treatment regimen and untreated cell control. Similarly, IRRV and CV-PEE mix showed obviously higher reactive oxygen species [ROS] values than PC3 and A549 cell treatments with CV and PEE. 相似文献
987.
Synthesis of several O‐ethyl phos‐phorodiamidates derived from unsubstituted, or 6‐bromo‐, or 6‐nitro‐3‐amino‐2‐methyl‐3H‐quinazolin‐4‐one and either amino acid esters or fatty amines is described. These compounds showed high insecticidal activity toward mosquito larvae, with lethal concentrations LC50 and LC90 as low as 0.028 and 1.724 ppm, respectively. The highest activity was observed with those compounds containing both a nitro substituent and a 10‐carbon‐atom fatty‐amine moiety. Multiple regression analysis was used to explain the larvicidal activity variation of these compounds. The larvicidal activity generally decreased according to the following order of amino acid moieties: glutamic acid > methionine > glycine > alanine > phenylalanine. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 455–460, 1999 相似文献
988.
Mondal Arunendu Laskar Inamur R. Chaudhuri Nirmalendu Ray Mostafa Golam Ghosh Ashutosh Prasad J. Shashidhara 《Transition Metal Chemistry》1999,24(3):282-286
[NiL2](NO3)2 (1) and [NiL2](CF3CO2)2 (2) (L = N2-methyldiethylenetriamine] have been synthesized and their X-ray single crystal structures have been determined. The triamines are ligated to NiII s-facially in (1) and meridionally in (2), with a NiN6 chromophore in each complex. 相似文献
989.
Heba A. El Gizawy Sylvia A. Boshra Ahmed Mostafa Sara H. Mahmoud Muhammad I. Ismail Aisha A. Alsfouk Azza T. Taher Ahmed A. Al-Karmalawy 《Molecules (Basel, Switzerland)》2021,26(19)
In response to the urgent need to control Coronavirus disease 19 (COVID-19), this study aims to explore potential anti-SARS-CoV-2 agents from natural sources. Moreover, cytokine immunological responses to the viral infection could lead to acute respiratory distress which is considered a critical and life-threatening complication associated with the infection. Therefore, the anti-viral and anti-inflammatory agents can be key to the management of patients with COVID-19. Four bioactive compounds, namely ferulic acid 1, rutin 2, gallic acid 3, and chlorogenic acid 4 were isolated from the leaves of Pimenta dioica (L.) Merr (ethyl acetate extract) and identified using spectroscopic evidence. Furthermore, molecular docking and dynamics simulations were performed for the isolated and identified compounds (1–4) against SARS-CoV-2 main protease (Mpro) as a proposed mechanism of action. Furthermore, all compounds were tested for their half-maximal cytotoxicity (CC50) and SARS-CoV-2 inhibitory concentrations (IC50). Additionally, lung toxicity was induced in rats by mercuric chloride and the effects of treatment with P. dioca aqueous extract, ferulic acid 1, rutin 2, gallic acid 3, and chlorogenic acid 4 were recorded through measuring TNF-α, IL-1β, IL-2, IL-10, G-CSF, and genetic expression of miRNA 21-3P and miRNA-155 levels to assess their anti-inflammatory effects essential for COVID-19 patients. Interestingly, rutin 2, gallic acid 3, and chlorogenic acid 4 showed remarkable anti-SARS-CoV-2 activities with IC50 values of 31 µg/mL, 108 μg/mL, and 360 µg/mL, respectively. Moreover, the anti-inflammatory effects were found to be better in ferulic acid 1 and rutin 2 treatments. Our results could be promising for more advanced preclinical and clinical studies especially on rutin 2 either alone or in combination with other isolates for COVID-19 management. 相似文献
990.
Hassane Assaaoudi Mostafa Ijjaali Abdelaziz Ennaciri Ian S. Butler Janusz A. Kozinski 《Journal of chemical crystallography》2007,37(9):601-608
Abstract The cyclotriphosphate salt, ErNa3(P3O9)2 · 9H2O, has been characterized by single-crystal X-ray diffraction [hexagonal, space group , with unit cell parameters of a = b = 30.8451(14), c = 12.8063(8) ?; Z = 18]. The structure consists of alternating layers of [P3O9]3− groups, ErO8 dodecahedra, Na(1)O6 and Na(2)O7 polyhedra linked together by water molecules. The P3O9 rings are grouped along the c-axis in a P3O9–ErO8 arrangement thereby producing broad, hexagonal channels of diameter of 6.65 ? with a side dimension of 3.907 ?. The absence
of coincidences for the majority of the IR and Raman bands observed for the cyclotriphosphate salt is in accord with the centrosymmetric
structure of the material. The vibrational spectra have been interpreted on the basis of factor group effects.
Graphical abstract
We report the crystal structure and vibrational spectra of erbium trisodium bis(cyclotriphosphate)nanohydrate salt
ErNa
3
(P
3
O
9
)
2
·
9H
2
O
H. Assaaoudi, M. Ijjaali, A. Ennaciri, I. S. Butler* and J. A. Kozinski
Crystal structure and vibrational spectra of erbium trisodium bis(cyclotriphosphate) nonahydrate,ErNa3(P3O9)2 · 9H2O.
Projection of the coordination polyhedra of ErNa3(P3O9)2 · 9H2O down the c axis 相似文献