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31.
Naser Zamani 《代数通讯》2013,41(4):1297-1307
Let (R,𝔪) be a local ring and s ≥ ?1. Using the notion of M-sequence in dimension > s, we introduce Cohen–Macaulay modules in dimension > s. Among other things concerning Cohen–Macaulay modules in dimension > s, some finiteness results of the support and the associated primes of local cohomology modules are investigated. 相似文献
32.
33.
Rozita Zoghi Majid M. Heravi Naser Montazeri Masoud Mohammadi Zeydi Tayebeh Hosseinnejad 《应用有机金属化学》2020,34(4):e5435
A novel polymer supported [poly (styrene-co-maleic imide) (SMI)]Cu(I) nano-particles was prepared via in situ reaction of 4-amino-5-methyl-4H-1,2,4-triazole-3-thione with [poly (styrene-co-maleic anhydride)] (SMA) along with immobilization of CuI. These nano-particles were fully characterized by using scanning electron microscopy (SEM), energy dispersive spectroscopy analysis, Xray (EDAX), inductively coupled plasma (ICP) analysis, 1H NMR and FT-IR techniques. Moreover, the structural and electronic features of metal–ligand interactions in the complex model of polymer-supported copper nanocatalyst were assessed using density functional theory calculations. The catalytic activity of these supported Cu(I) nonoparticles was examined in one of the classiest name reaction so–called “click reaction” which is coined K. B Sharpless for the regioselective synthesis of 1,2,3-triazole derivatives using a multicomponent reaction (MCR) involving benzyl halides, sodium azide and terminal alkynes in water as a green solvent. This heterogeneous catalyst showed excellent catalytic activity and was separated by simple filtration and was used at least in five consecutive runs without a significant decrease in its activity. 相似文献
34.
Ahmad Ahmeda Naser Abbasi Hori Ghaneialvar Mohammad Mahdi Zangeneh Akram Zangeneh 《应用有机金属化学》2020,34(4):e5480
The aim of the study was the rapid green synthesis of titanium nanoparticles using the aqueous extract of Falcaria vulgaris leaves (TiNPs@FV) and exploring their antioxidant, cytotoxicity, antifungal, antibacterial, and cutaneous wound healing activities under in vitro and in vivo condition. These nanoparticles were characterized by UV-Vis, Fourier transform-infrared(FT-IR), X-ray diffraction XRD), field emission-scanning electron microscopy FE-SEM), and transmission electron microscopy TEM) analyses. The synthesized TiNPs@FV had great cell viability on human umbilical vein endothelial cells and indicted this method was nontoxic. DPPH (2,2-diphenyl-1-picrylhydrazyl) test revealed similar antioxidant potentials for F. vulgaris, TiNPs@FV, and butylated hydroxytoluene. All data of antibacterial, antifungal, and cutaneous wound healing tests were analyzed by SPSS 22 software. In the antimicrobial part of this study, TiNPs@FV indicated higher antifungal and antibacterial effects than all standard antibiotics (p ≤ 0.01). Minimal inhibitory concentration (MIC) and minimal fungicidal concentration of TiNPs@FV against all fungi were at 2–4 mg/mL and 2-8 mg/mL ranges, respectively. But, MIC and minimal bactericidal concentration of TiNPs@FV against all bacteria were at 2-8 mg/mL and 2-16 mg/mL ranges, respectively. In the part of cutaneous wound healing, use of TiNPs@FV ointment significantly (p ≤ 0.01) raised the wound contracture, vessel, hydroxyl proline, hexuronic acid, hexosamine, fibrocyte, and fibrocytes/fibroblast rate and significantly (p ≤ 0.01) decreased the wound area, total cells, neutrophil, and lymphocyte compared to other groups in rats. The results of FT-IR, UV-Vis, XRD, TEM, and FE-SEM confirm that the aqueous extract of F. vulgaris leaves can be used to yield titanium nanoparticles with a notable amount of remedial effects. 相似文献
35.
Basically there exists a significant interest in dynamic friction models [1]. These dynamic models describe μ as a time dependent process parameter. The indentification of the belonging parameters needs a special kind of measurements. This is due to the fact that the measurements with the classical pin on disk arrangement give stationary values of μ only, the measurements of dynamic properties are even infeasible. A new advanced tribometer has been developed. This tribometer allows measurements of complex unsteady friction processes. The experimental characteristics and the realization of this novel tribometer are presented by concrete measurements. (© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
36.
Ramin Maleki Nasim Mohammad Nezhad Naser Samadi Khalil Farhadi 《Mikrochimica acta》2009,165(1-2):97-101
Dispersive liquid–liquid microextraction (DLLME) in conjunction with high-performance liquid chromatography-diode array detection (HPLC-DAD) has been applied to the extraction and determination of EDTA in sediments and water samples. The effect of extraction, nature and volume of disperser solvent, pH value of sample solution, extraction time and extraction temperature were investigated. Under the optimal conditions the analytical range of EDTA was from 3.0 to 50.0 μg L?1 with a correlation coefficient of 0.9982 and a detection limit of 1.7 μg L?1. The relative standard deviation (RSD) was less than 5.4% (n?=?5), and the recovery values were in the range of 89–95%. The simplicity, high enrichment, high recovery and good repeatability are the main advantages of the method presented. The DLLME-HPLC-DAD method was successfully applied to the analysis of EDTA in aqueous samples. 相似文献
37.
Mahboubeh Rahmati-Rostami Cyrus Ghotbi Masih Hosseini-Jenab Amir Naser Ahmadi Amir Hossein Jalili 《The Journal of chemical thermodynamics》2009,41(9):1052-1055
The solubility of hydrogen sulphide in three ionic liquids, viz. 1-hexyl-3-methylilmidazolium hexafluorophosphate ([hmim][PF6]), 1-hexyl-3-methylimidazolium tetrafluoroborate ([hmim][BF4]), and 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([hmim][Tf2N]), at temperatures ranging from 303.15 K to 343.15 K and pressures up to 1.1 MPa were determined. The solubility values were correlated using the Krichevsky–Kasarnovsky equation and Henry’s constants were obtained at different temperatures. Partial molar thermodynamic functions of solvation such as standard Gibbs free energy, enthalpy, and entropy were calculated from the solubility results. Comparison of the values obtained show that the solubility of H2S in these three ionic liquids was in the sequence: [hmim][BF4] > [hmim][PF6] ≈ [hmim][Tf2N]. 相似文献
38.
Naser Foroughifar Akbar Mobinikhaledi Sattar Ebrahimi Mohammad Ali Bodaghi Fard Hassan Moghanian 《中国化学会会志》2009,56(5):1043-1047
Some new and optically active 1,2,4‐triazolo thiadiazoles bearing N‐phthaloyl‐l ‐amino acids were synthesized by reaction of 4‐amino‐5‐(3‐ or 4‐)pyridyl‐3‐mercapto‐(4H)‐1,2,4‐triazoles with N‐phthaloyl‐l ‐amino acids in the presence of phosphorus oxychloride. All the newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR and elemental analysis. 相似文献
39.
Arman Kiani-B Kia Fallahi Naser Pariz Henry Leung 《Communications in Nonlinear Science & Numerical Simulation》2009,14(3):863-879
In recent years chaotic secure communication and chaos synchronization have received ever increasing attention. In this paper, for the first time, a fractional chaotic communication method using an extended fractional Kalman filter is presented. The chaotic synchronization is implemented by the EFKF design in the presence of channel additive noise and processing noise. Encoding chaotic communication achieves a satisfactory, typical secure communication scheme. In the proposed system, security is enhanced based on spreading the signal in frequency and encrypting it in time domain. In this paper, the main advantages of using fractional order systems, increasing nonlinearity and spreading the power spectrum are highlighted. To illustrate the effectiveness of the proposed scheme, a numerical example based on the fractional Lorenz dynamical system is presented and the results are compared to the integer Lorenz system. 相似文献
40.
Ali Mirzaei Dakdareh Cavus Falamaki Naser Ghasemian 《Journal of nanoparticle research》2018,20(11):309
A novel nano-size MnxOy/clinoptilolite catalyst of high activity for propane-SCR reaction of NOx at low temperatures has been synthesized by a hydrothermal method in a temperature range of 80–180 °C. The optimum synthesis temperature resulting in maximum NOx conversion was 150 °C. An optimum manganese oxide loading of 0.2 wt.% results in the best catalytic behavior (71% NOx conversion). All catalysts exhibited an optimal propane-SCR reaction temperature of 200 °C. The optimum catalyst produces no detectable CO (GHSV 27,000 h) at 200 °C. Manganese in the optimum catalyst exists as Mn2+ (37.8%), Mn3+ (14.2%), and Mn4+ (48%). 相似文献