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11.
Fahmy M. Asaad Nazih Latif Nawal Mishriky Ibrahim Zeid 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):17-18
Abstract In the present investigation, the authors could obtain a new series of spiranes (1) through the reaction of the high potential quinone tetrachloro-o-benzoquinone with 2-aryl-3-phenyl-3H-quinazoline-4-thiones. Thus, 2,3-diphenyl- (2a), 2-p-tolyl-3-phenyl- (2b) and 2-p-anisyl-3-phenyl- (2c)-3H-quinazoline-4-thiones react readily with tetrachloro-o-benzoquinone, in boiling toluene, to give the corresponding spiro-1,3-benzodioxole-2,4′-(3′H)-quinazolines (1a-c), respectively. 相似文献
12.
Tauqeer Ahmad Yasir Ayesha Khan Milan Skalicky Allah Wasaya Muhammad Ishaq Asif Rehmani Naeem Sarwar Khuram Mubeen Mudassir Aziz Mohamed M. Hassan Fahmy A. S. Hassan Muhammad Aamir Iqbal Marian Brestic Mohammad Sohidul Islam Subhan Danish Ayman EL Sabagh 《Molecules (Basel, Switzerland)》2021,26(9)
Soil salinity disrupts the physiological and biochemical processes of crop plants and ultimately leads to compromising future food security. Sodium nitroprusside (SNP), a contributor to nitric oxide (NO), holds the potential to alleviate abiotic stress effects and boost tolerance in plants, whereas less information is available on its role in salt-stressed lentils. We examined the effect of exogenously applied SNP on salt-stressed lentil plants by monitoring plant growth and yield-related attributes, biochemistry of enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) amassing of leaf malondialdehyde (MDA) and hydrogen peroxide (H2O2). Salinity stress was induced by NaCl application at concentrations of 50 mM (moderate salinity) and 100 mM (severe salinity), while it was alleviated by SNP application at concentrations of 50 µM and 100 µM. Salinity stress severely inhibited the length of roots and shoots, the relative water content, and the chlorophyll content of the leaves, the number of branches, pods, seeds, seed yield, and biomass per plant. In addition, MDA, H2O2 as well as SOD, CAT, and POD activities were increased with increasing salinity levels. Plants supplemented with SNP (100 µM) showed a significant improvement in the growth- and yield-contributing parameters, especially in plants grown under moderate salinity (50 mM NaCl). Essentially, the application of 100 µM SNP remained effective to rescue lentil plants under moderate salinity by regulating plant growth and biochemical pathways. Thus, the exogenous application of SNP could be developed as a useful strategy for improving the performance of lentil plants in salinity-prone environments. 相似文献
13.
Sayed Abdel-Khalek Angelo Plastino Abdel-Shafy Fahmy Obada 《Central European Journal of Physics》2011,9(6):1426-1433
The dynamics of the Buck and Sukumar model (B. Buck and C. V. Sukumar, Phys. Lett. A 81, 132 (1981)) is investigated using
different semi-classical information-theory tools. Their interplay reveals somewhat unexpected features. A new signature for
the classical-quantum barrier is encountered thereby. 相似文献
14.
H.M. Fahmy M. Abdul-Wahab H. Abdel-Reheem 《Journal of Electroanalytical Chemistry》1985,184(1):135-145
The electroreduction of two series of rhodanine derivatives has been investigated at the DME. The first wave was assigned to the saturation of the azomethine linkage and the reduction of the ethylenic double bond in series I and II, respectively. On the other hand, the second wave in both series was assigned to the reduction of the C-S group and partly to the catalytic hydrogen evolution catalyzed by these compounds. 相似文献
15.
AA Yan LI Kai CAO ZhongHua & HU WenRui Key Laboratory of Microgravity 《中国科学:物理学 力学 天文学(英文版)》2011,(2)
The dependency of the critical Marangoni number on the geometrical aspect ratio of the floating half zone is essential to predict the onset of oscillatory thermocapillary convection.The experimental studies in the microgravity conditions on floating half zones of several centimeters in diameter have predicted that the critical Marangoni number increases with the increasing aspect ratio,and the terrestrial experimental studies have predicted the contradictory conclusion for floating half zones of several mil... 相似文献
16.
The time-delayed Burgers equation is introduced and the improved tanh-function method is used to construct exact multiple-soliton and triangular periodic solutions. For an understanding of the nature of the exact solutions that contained the time-delay parameter, we calculated the numerical solutions of this equation by using the Adomian decomposition method and the variational iteration method (IVM) to the boundary value problem. 相似文献
17.
Non-Gravitational Effects with Density-Matching in Evaluating the Influence of Sedimentation on Colloidal Coagulation 下载免费PDF全文
The method of density matching between the solid and liquid phases is often adopted to effectively eliminate the effect of sedimentation of suspensions in studies on dynamic behaviour of a colloidal system. However, the associated changes in the solvent composition may bring side effects to the properties investigated and therefore might lead to a faulty conclusion if the relevant correction is not made. To illustrate the importance of this side effect, we present an example of the sedimentation influence on the coagulation rate of suspensions of 2μm (diameter) polystyrene. The liquid mixtures, in the proper proportions of water (H2O), deuterium oxide (D2O) and methanol (MeOH) as the liquid phase, density-matched and unmatched experiments are performed. Besides the influence of viscosity, the presence of methanol in solvent media, used to enhance the sedimentation effect, causes significant changes (reduction) in rapid coagulation rates compared to that in pure water. Without the relevant corrections for those non-gravitational factors it seems that gravitational sedimentation would retard the coagulation. The magnitude of the contribution from the non-gravitational factor is quantitatively determined, making the relevant correction possible. After necessary the influence of the sedimentation on coagulation rates at corrections for all factors, our experiments show that the initial stage of the coagulation is not observable. 相似文献
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20.
Saleh Ahmed Mohamed Ehab A. Drees Mohamed O. El-Badry Afaf S. Fahmy 《Applied biochemistry and biotechnology》2010,160(7):2054-2065
α-Amylase activity was screened in the peel, as waste fruit, of 13 species and cultivars of Egyptian citrus. The species Citrus sinensis cv. Abosora had the highest activity. α-Amylase AI from Abosora peel was purified to homogeneity using anion and cation-exchange,
and gel filtration chromatographies. Molecular weight of α-amylase AI was found to be 42 kDa. The hydrolysis properties of
α-amylase AI toward different substrates indicated that corn starch is the best substrate. The α-amylase had the highest activity
toward glycogen compared with amylopectin and dextrin. Potato starch had low affinity toward α-amylase AI but it did not hydrolyze
β-cyclodextrin and dextran. Apparent Km for α-amylase AI was 5 mg (0.5%) starch/ml. α-Amylase AI showed optimum activity at
pH 5.6 and 40 °C. The enzyme was thermally stable up to 40 °C and inactivated at 70 °C. The effect of mono and divalent metal
ions were tested for the α-amylase AI. Ba2+ was found to have activating effect, where as Li+ had negligible effect on activity. The other metals caused inhibition effect. Activity of the α-amylase AI was increased
one and half in the presence of 4 mM Ca2+ and was found to be partially inactivated at 10 mM Ca2+. The reduction of starch viscosity indicated that the enzyme is endoamylase. The results suggested that, in addition to citrus
peel is a rich source of pectins and flavanoids, α-amylase AI from orange peel could be involved in the development and ripening
of citrus fruit and may be used for juice processing. 相似文献