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1.
Gold nanoparticles have unique and excellent medical and nonmedical properties and application compared with other metallic nanoparticles. Recently, they have been used for the prevention, control, and treatment of bacterial and fungal diseases. In the recent study, fresh and clean leaves of Allium noeanum Reut. ex Regel leaves have been used for the synthesis of gold nanoparticles. Also, we evaluated the cytotoxicity, antioxidant, and antibacterial properties of HAuCl4, A. noeanum, and the synthesized nanoparticles (Au NPs). These nanoparticles were analyzed by FT‐IR, UV, XRD, EDS, FE‐SEM, and TEM tests. FTIR results offered antioxidant compounds in the plant were the sources of reducing power, reducing gold ions to Au NPs. In TEM images revealed an average diameter of 10‐30 nm. At the beginning of biological experiments, DPPH free radical scavenging test was carried out to examine the antioxidant property. Also, in the bacterial part of this study, the concentration of HAuCl4, A. noeanum, and AuNPs with minimum dilution and no turbidity was considered MIC. To determine MBC, 60 μL of MIC and three preceding chambers were cultured on Muller Hinton Agar. The minimum concentration with no bacterial growth was considered MBC. Au NPs revealed excellent antioxidant potential against DPPH, non‐toxicity property against human umbilical vein endothelial cells, and antibacterial activities against Streptococcus pneumonia, Bacillus subtilis, Staphylococcus aureus, Staphylococcus saprophyticus, Salmonella typhimurium, Pseudomonas aeruginosa, Shigella flexneri, and Escherichia coli O157:H7. These findings show that the inclusion of A. noeanum extract improves the solubility of Au NPs, which led to a notable enhancement in the antioxidant and antibacterial effects. 相似文献
2.
Sarafraz M. M. Tian Zhe Tlili I. Kazi Sabeena Goodarzi Marjan 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2435-2445
Journal of Thermal Analysis and Calorimetry - In the present study, a set of experiments were accomplished to appraise the thermal performance and heat transfer of n-pentane-acetone and... 相似文献
3.
Cellulose - Bookkeeper, the most widely used deacidification process based on MgO particles, was systematically evaluated on two sets of nonvaluable historical paper samples. Established analytical... 相似文献
4.
Marjan Hematyar Ali Es-haghi Majid Soleimani Ali Rezaie Mokarram 《Journal of the Iranian Chemical Society》2017,14(12):2665-2671
In this work, magnetic solid-phase extraction based on sodium dodecyl sulfate-coated Fe3O4 nanoparticles has been successfully applied for extraction and preconcentration of trace amounts of nystatin from water and vaccine samples prior to high-performance liquid chromatography–ultraviolet detection. Various experimental parameters affecting extraction and recovery of the analyte, such as the amount of sodium dodecyl sulfate, pH of the sample solution, salt concentration, extraction time, sample volume and desorption conditions, were systematically studied and optimized. Under optimized conditions, nystatin was quantitatively extracted. Proper linear range with good coefficient of determination, (R 2 > 0.99) and limit of detection and quantification (based on signal-to-noise ratios of 3 and 10) of 2.0 and 5.0 µg L?1, over the investigated concentration range (5–700 µg L?1), were obtained, respectively. The intra-day and inter-day relative standard deviations at 50 µg L?1 level of NYS were 1.4 and 4.5% based on six replicate determinations. The accuracy of the method was evaluated by recovery measurements on spiked samples. Suitable recoveries of 96–102 and 26–44% were achieved (at spiked levels of 50, 300 and 500 µg L?1) for water and vaccine samples, respectively. 相似文献
5.
Waqas Hassan Farooq Umar Khan Shan Ali Alshehri Hashim M. Goodarzi Marjan 《Journal of Thermal Analysis and Calorimetry》2021,145(4):2033-2044
Journal of Thermal Analysis and Calorimetry - The increasing need of the modern era of technology for better ways to increase the heat transfer performance of thermal systems has made nanoliquids... 相似文献
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Firouz Matloubi Moghaddam Zohreh Mirjafary Marjan Jebeli Javan Sara Motamen Hamid Saeidian 《Tetrahedron letters》2014
A mild and efficient tandem process for the synthesis of new highly substituted 2-pyrones starting from commercially available 2-arylacetic acids has been developed. The synthesis is based on the Knoevenagel condensation of 1,3-cyclohexadiones with various β-formyl-esters, followed by lactonization in the presence of nano ZnO (20 mol %). Moderate to high yields and readily available cheap starting materials are the key features of the present method. 相似文献
8.
The Origin of the Selectivity and Activity of Ruthenium‐Cluster Catalysts for Fuel‐Cell Feed‐Gas Purification: A Gas‐Phase Approach 下载免费PDF全文
Dr. Sandra M. Lang Prof. Dr. Thorsten M. Bernhardt Marjan Krstić Prof. Dr. Vlasta Bonačić‐Koutecký 《Angewandte Chemie (International ed. in English)》2014,53(21):5467-5471
Gas‐phase ruthenium clusters Run+ (n=2–6) are employed as model systems to discover the origin of the outstanding performance of supported sub‐nanometer ruthenium particles in the catalytic CO methanation reaction with relevance to the hydrogen feed‐gas purification for advanced fuel‐cell applications. Using ion‐trap mass spectrometry in conjunction with first‐principles density functional theory calculations three fundamental properties of these clusters are identified which determine the selectivity and catalytic activity: high reactivity toward CO in contrast to inertness in the reaction with CO2; promotion of cooperatively enhanced H2 coadsorption and dissociation on pre‐formed ruthenium carbonyl clusters, that is, no CO poisoning occurs; and the presence of Ru‐atom sites with a low number of metal–metal bonds, which are particularly active for H2 coadsorption and activation. Furthermore, comprehensive theoretical investigations provide mechanistic insight into the CO methanation reaction and discover a reaction route involving the formation of a formyl‐type intermediate. 相似文献
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10.
Synthetic Approaches towards the Sulfonamide Substituted‐1,5‐Diarylimidazole‐2‐thiones as Selective Cyclooxygense‐2 inhibitors 下载免费PDF全文
Latifeh Navidpour Mohsen Amini Ramin Miri Omidreza Firuzi Marjan Tavakkoli Abbas Shafiee 《Journal of heterocyclic chemistry》2014,51(1):71-79
A new series of sulfonamide substituted 1,5‐diarylimidazole, possessing C‐2 alkylthio moiety, were synthesized for their cyclooxygense‐2 (COX‐2) inhibitory activity starting from condensation of N,N‐dibenzylaminosulfonylphenacylamine hydrochloride ( 2 ) and corresponding isothiocyanate in the presence of Et3N, followed by alkylation in the basic medium. In concomitant with these intermediates, 2‐arylamino‐5‐arylthiazole derivatives 5 were also produced. The ratio of these two products was variable with different isothiocyanates. Final debenzylation was achieved using concentrated sulfuric acid to give the title sulfonamides 8 . 相似文献