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901.
Necessary and sufficient conditions for oscillation of second‐order dynamic equations on time scales
Yong Zhou Bashir Ahmad Ahmed Alsaedi 《Mathematical Methods in the Applied Sciences》2019,42(13):4488-4497
In this paper, we establish necessary and sufficient conditions for oscillation of second‐order strongly superlinear and strongly sublinear dynamic equations. Our results unify and improve many known results in the literature. 相似文献
902.
Ahmad Sohail Ashraf Muhammad Ali Kashif 《Journal of Thermal Analysis and Calorimetry》2021,144(3):941-953
Journal of Thermal Analysis and Calorimetry - Among numerous methods which have been employed to reinforce the thermal efficiency in many systems, one is the thermal radiation which is a mode of... 相似文献
903.
Ahmad Shafiq Nadeem Sohail Muhammad Noor Khan Muhammad Naveed 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1187-1199
Journal of Thermal Analysis and Calorimetry - Cattaneo–Christov with variable thermal relaxation time and entropy generation is the main concern of this study. The micropolar fluid with... 相似文献
904.
Abeer Mogadem Mohamed Ali Almamary Naji Arafat Mahat Khairunadwa Jemon Wan Azlina Ahmad Imran Ali 《Molecules (Basel, Switzerland)》2021,26(4)
The current research is focused on studying the biological efficacy of flexirubin, a pigment extracted from Chryseobacterium artocarpi CECT 8497.Different methods such as DPPH, H2O2, NO•, O2•−, •OH, lipid peroxidation inhibition by FTC and TBA, ferric reducing and ferrous chelating activity were carried out to evaluate the antioxidant activity of flexirubin. Molecular docking was also carried out, seeking the molecular interactions of flexirubin and a standard antioxidant compound with SOD enzyme to figure out the possible flexirubin activity mechanism. The new findings revealed that the highest level of flexirubin exhibited similar antioxidant activity as that of the standard compound according to the H2O2, •OH, O2•−, FTC and TBA methods. On the other hand, flexirubin at the highest level has shown lower antioxidant activity than the positive control according to the DPPH and NO• and even much lower when measured by the FRAP method. Molecular docking showed that the interaction of flexirubin was in the binding cavity of the SOD enzyme and did not affect its metal-binding site. These results revealed that flexirubin has antioxidant properties and can be a useful therapeutic compound in preventing or treating free radical-related diseases. 相似文献
905.
Ameneh Izadi Masoumi Shadi Sadegh Afshari Amri S. Ahmad Nabavi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(1):158-166
Russian Journal of Physical Chemistry A - The interaction of many biomarker gas molecules on pure, AlB-doped and GaB-doped boron nitride nanotube was studied by the density functional theory method... 相似文献
906.
Malik Aijaz Ahmad Ojha Suvash Chandra Schaduangrat Nalini Nantasenamat Chanin 《Molecular diversity》2022,26(1):467-487
Molecular Diversity - Alzheimer’s disease (AD) is one of the most common forms of dementia and is associated with a decline in cognitive function and language ability. The deficiency of the... 相似文献
907.
Mohammad Ali Kamyabi Fatemeh Soleymani-Bonoti Leila Taheri Ahmad Morsali Hassan Hosseini-Monfared 《应用有机金属化学》2020,34(5):e5562
Oxygen reduction at the polarized water/1,2-dichloroethane (DCE) interface catalyzed by a Cu (II) coordination polymer (Cu–pol) was studied with two lipophilic electron donors ferrocene (Fc) and tetrathiafulvalene (TTF). The results of the ion transfer voltammetry and two-phase shake flask experiments suggest proceeding of the catalytic reaction as proton-coupled electron transfer reduction of oxygen to hydrogen peroxide and water. In this process, while the protons supplied from the aqueous phase, the electrons provided from the organic phase by the weak electron donor, Fc. The O2 molecule takes a superoxide structure with Cu–pol which resulted to hydrogen peroxide or water on reduction. Furthermore, the results revealed that the apparent rate constant of TTF + Cu-pol is higher than that of Fc + Cu-pol system due to the faster kinetic reaction of TTF with respect to Fc. 相似文献
908.
Ahmad Ahmeda Mohammad Mahdi Zangeneh Shirin Mansooridara Zahra Malek Akram Zangeneh 《应用有机金属化学》2020,34(3):e5355
Metallic nanoparticles have gained significant attention in the area of biomedical technology. Because of its high surface area, metallic nanoparticles are being widely used in various fields including the medical and engineering sciences. One of the valuable applications of metallic nanoparticles especially copper, zinc, and iron nanoparticles is increasing the physiological function of central nervous system. Besides, Iranian people are using the Salvia chloroleuca for neuroprotective properties. In the present research, iron nanoparticles were biosynthesized by S. chloroleuca leaf aqueous extract as reducing and stabilizing agents. Also, we revealed the protective effect of FeNPs in methadone-treated PC12 cells. FeNPs were characterized and analyzed using common nanotechnology techniques including FT-IR, UV–Vis. spectroscopy; EDS, TEM, and FE-SEM. TEM and FE-SEM images revealed a uniform spherical morphology for FeNPs. In the biological part of the current study, the both treatments of FeNPs significantly (p ≤ 0.01) reduced the cell cytotoxicity and cell death index as well as increased the cell viability and cell proliferation in methadone-treated PC12 cells. In these treatments, mitochondrial membrane potential significantly (p ≤ 0.01) increased compared to methadone-induced PC12 cells. DPPH free radical scavenging test was did to evaluate the antioxidant potentials of FeCl3, S. chloroleuca, and FeNPs. DPPH test indicated similar antioxidant activities for S. chloroleuca, FeNPs, and butylated hydroxytoluene. In current experiment, we concluded that iron nanoparticles biosynthesized by S. chloroleuca leaf aqueous extract suppressed methadone-induced cell death in a dose-dependent manner in PC12 cells. 相似文献
909.
Sepideh Gharehyakheh Ahmad Ahmeda Amir Haddadi Morteza Jamshidi Masoumeh Nowrozi Mohammad Mahdi Zangeneh Akram Zangeneh 《应用有机金属化学》2020,34(4):e5492
Because herbal nanoparticles have antimicrobial properties, researchers have tried to synthesize them to aid in increasing the shelf time of food and food products. In this regard, gold nanoparticles (AuNPs) synthesized by plants are particularly important. In this study, fresh and clean leaves of Satureja hortensis were selected for the synthesis of AuNPs. We also evaluated the efficacy of these nanoparticles to increase the shelf life of and remove Escherichia coli O157:H7 and Listeria monocytogenes from minced camel's meat. The nanoparticles were analyzed by UV–visible spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction tests. The FT-IR spectroscopy results demonstrated that the antioxidant compounds in the plant were the sources of reducing power, reducing gold ions to AuNPs. FE-SEM and TEM images revealed the size of the nanoparticles to be 22.26 nm. The 2,2-diphenyl-1-picrylhydrazyl test revealed similar antioxidant potentials for S. hortensis, AuNPs, and butylated hydroxytoluene. S. hortensis and AuNPs had high cell viability dose-dependently against the human umbilical vein endothelial cell line. At the beginning of the food industry part of this experiment, all samples of control, S. hortensis, and AuNPs were preserved at 4°C for 20 days. During these 20 days, the sensory, chemical, and microbiological parameters were assessed for all samples. AuNPs significantly inhibited the growth of E. coli and L. monocytogenes. In addition, AuNPs significantly increased the protein carbonyl content, thiobarbituric acid reactive substances, pH, peroxide value, total volatile base nitrogen, and sensory attributes (color, odor, and overall acceptability). The best results were seen in AuNPs (1%). These findings reveal that the inclusion of S. hortensis extract improves the solubility of AuNPs, which led to a notable enhancement in their preservative and antibacterial effects. 相似文献
910.