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101.
The Galerkin finite element model (GFEM) may provide oscillatory results when employed to predict contaminant transport in groundwater unless a very fine mesh is used. Adaptation of a very fine mesh may make the application of the GFEM impractical to field problems. The Petrov—Galerkin finite element models (PGFEMs) can provide oscillation free results for relatively coarser mesh. However, the PGFEM violates the Galerkin principle and introduces large “numerical” dispersion. The objective of this paper has been to develop accurate criteria to improve the applicability of the GFEM to obtain oscillation free accurate results for coarser mesh and compare its performance with that of the PGFEM. It has been shown that the GFEM provides oscillation free accurate results for coarser mesh with Peclet number Pe 20. Further, the GFEM prediction has always been more accurate than the PGFEM for a variety of source configurations and flow fields. 相似文献
102.
In a biological process where the herbal tea (Stachys lavandulifolia) aqueous extract was applied as a capping and reducing agent, nanoparticles (NPs) of silver (Ag) were synthesized. These AgNPs were characterized using Fourier transform‐infrared spectroscopy, field emission‐scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, transmission electron microscopy and ultraviolet–visible spectroscopy. The synthesized AgNPs had great cell viability dose‐dependently [investigating the effect of the plant on human umbilical vein endothelial cell line] and indicated this method was non‐toxic. In this study, the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging test was carried out to examine antioxidant properties, which revealed similar antioxidant properties for AgNPs and butylated hydroxytoluene. Agar diffusion tests were applied to determine the antibacterial characteristics. The macro‐broth tube test was run to determine minimum inhibitory concentration. All data of antibacterial and cutaneous wound‐healing examinations were analyzed by SPSS 21 software (Duncan post hoc test). AgNPs showed higher antibacterial property than all standard antibiotics (p ≤ 0.01). Also, AgNPs prevented the growth of all bacteria at 2–8 mg/ml concentrations and destroyed them at 2–16 mg/ml concentrations (p ≤ 0.01). For the in vivo experiment, after creating the cutaneous wound, the rats were randomly divided into six groups: untreated control; treatment with Eucerin basal ointment; treatment with 3% tetracycline ointment; treatment with 0.2% AgNO3 ointment; treatment with 0.2% S. lavandulifolia ointment; and treatment with 0.2% AgNPs ointment. These groups were treated for 10 days. For histopathological and biochemical analysis of the healing trend, a 3 × 3‐cm section was prepared from all dermal thicknesses at day 10. Use of AgNPs ointment in the treatment groups substantially reduced (p ≤ 0.01) the wound area, total cells, neutrophil, macrophage and lymphocyte, and remarkably raised (p ≤ 0.01) the wound contracture, hydroxyl proline, hexosamine, hexuronic acid, fibrocyte and fibrocytes/fibroblast rate compared with other groups. Seemingly, AgNPs can be used as a medical supplement owing to their non‐cytotoxic, antioxidant, antibacterial and cutaneous wound‐healing properties. 相似文献
103.
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
104.
Waqas M. Akram Nimra Asghar Z. Gulzar M. M. Javed M. A. 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2069-2074
Journal of Thermal Analysis and Calorimetry - Heat transportation analysis subjected to porous medium consideration has increased because of industrial and engineering utilization. Typical examples... 相似文献
105.
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
106.
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
107.
Abdul Khaliq Syed Muhammad Ali Shah Muhammad Akram Naveed Munir Muhammad Daniyal Muhammad Irshad 《Natural product research》2020,34(13):1951-1955
AbstractThe olive (Olea europaea L.) is a worldwide famous tree crop having valuable commercial role due to nutritional as well as therapeutic benefits obtained from its edible oil. Eight varieties of Olea europaea L. fruits were obtained from three Agricultural research institutes located in different areas of Pakistan including Quetta, Lorallia and Zhob to extract and determine their oil contents by conventional method as solvent extraction (soxhlet apparatus). Statistical analysis showed significant (p?=?0.002) difference in oil composition of collected plants. Highest amount (percentage) of oil was obtained from Gemlik variety (65%) from Lorallia and lowest oil content from Dolece-agogia variety (17.5%) collected from Quetta. Further research is under consideration to rule out best suitable factors including some soil and environmental factors to obtained more potential cultivars of Olea europaea in Pakistan. 相似文献
108.
Saeid Farhadi Mozhgan Afshari Mansoureh Maleki Zaynab Babazadeh 《Tetrahedron letters》2005,46(49):8483-8486
An efficient, selective and green procedure for the photocatalytic oxidation of primary and secondary benzylic alcohols to the corresponding aldehydes and ketones has been achieved using silica-encapsulated H3PW12O40 as a recyclable heterogeneous photocatalyst in acetonitrile under oxygen gas as the sole reoxidant of the catalyst. 相似文献
109.
110.