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121.
Molecular Diversity - In this research, QSAR modeling was carried out through SMILES of compounds and on the basis of the Monte Carlo method to predict the antioxidant activity of 79 derivatives of... 相似文献
122.
Acoustic performance of dissipative silencer was evaluated to determine the effectiveness of perforated duct porosity and absorbent material density in reducing occupational noise exposure propagated from centrifugal fan. Design charts were applied to predict noise reduction and length of a dissipative silencer. Dissipative silencers with various punched duct porosity (14%, 30% and 40%) and sound absorbent density (80 Kg/m3, 120 Kg/m3, and 140 Kg/m3) were designed and fabricated. According to ISO9612 and ISO11820, noise level was measured before and after installing all nine test silencers at fixed workstations around the discharge side of a centrifugal fan in a manufacturing plant. On average, the noise level at the discharge side of a fan without silencer was measured to be 93.6 dBA, whereas it was significantly mitigated by 67.4 dBA to 70.1 dBA after installing all silencers. Dynamic insertion loss for a dissipative silencer with 100 cm length was predicted to be 27.9 dB, which was in agreement with experimental ones. Although, there was no significant differences between insertion loss of silencers, the one with 30% porosity and 120 Kg/m3 rock wool density had the highest insertion loss of 26.2 dBA. Dissipative silencers noticeably reduced centrifugal fan noise exposures. Increasing sound absorbent density and duct porosity up to a certain limit could probably be effective in noise reduction of dissipative silencers. 相似文献
123.
Ahmadpour Javad Ahmadi Mahyar Javdani Amirhossein 《Journal of Thermal Analysis and Calorimetry》2019,135(3):1943-1949
Journal of Thermal Analysis and Calorimetry - Nowadays, most of the world’s energy consumption is from fossil fuels. One of these fossil fuels is natural gas condensate which consists of... 相似文献
124.
Methylthiouracil‐modified Carbon Paste Electrode as a New Voltammetric Sensor Based on a 1,4‐Michael Addition Reaction for Detection of Dopamine 下载免费PDF全文
M. Arab Chamjangali A. Ahmadi Reskety N. Goudarzi G. Bagherian 《Electroanalysis》2015,27(12):2708-2717
A sensitive dopamine sensor was constructed based on the modified carbon paste electrode with methylthiouracil as a nucleophile in the 1,4‐Michael addition reaction. An ECE mechanism was suggested for dopamine oxidation at the modified electrode. Design of experiments was used in the optimization of variables. Under the optimum conditions, calibration graph was linear in the range of 0.20–15.0 µM with a detection limit of 73 nM. The relative standard deviations (n=5) for 0.50 µM of dopamine was 3.83 %. The selectivity of the sensor was also studied. The developed sensor was applied for analysis of pharmaceutical and biological samples. 相似文献
125.
Moutab Sahihazar Milad Ahmadi Mohammad Taghi Nouri Mina Rahmani Meisam 《Journal of Solid State Electrochemistry》2019,23(6):1641-1650
Journal of Solid State Electrochemistry - Nanostructured carbon material (NSCM) based chemiresistive sensors are popular for sensing different analytes because of their high sensitivity, low cost,... 相似文献
126.
Majid Rezaeivala Musa Ahmadi Burjor Captain Serap Şahin-Bölükbaşı Ahmad Ali Dehghani-Firouzabadi Robert William Gable 《应用有机金属化学》2020,34(2):e5325
A new unsymmetrical five-coordinate Schiff base ligand (HL) with an N4O donor set ( 2 ) has been prepared by condensation of N1-(2-morpholinoethyl)-N1-([pyridine-2-yl]methyl)propane-1,3-diamine with 2-hydroxy-benzaldehyde. Metal complexes [ML]n+ (M = Zn2+, Cd2+, Mn2+, Cu2+, Ni2+, Ag+, Fe3+, and Co2+ ( 3–10 ) were synthesized by the reaction of the ligand and metal salts in ethanol. The resulting products were characterized by elemental analyses, infrared, 1H and 13C nuclear magnetic resonance spectra (in the case of Cd and Zn complexes), UV–Vis, electrospray ionization-mass spectrometric, and conductivity measurements. The structure of the complexes [ZnL](ClO4) ( 3 ), [CdL](ClO4) ( 4 ), and [CuL](ClO4) ( 7 ) has been determined by single-crystal X-ray diffraction analysis. The metal complexes were determined to have a distorted trigonal bipyramidal (Zn and Cd) or a distorted square pyramidal (Cu) geometry. The cytotoxic potential of each compound (1–10) against MCF-7 and MDA-MB-231 (breast cancer cells), PC-3 (prostate cancer cells), and WI-38 human normal lung fibroblast cells was evaluated using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay. Compounds 1, 2, and 10 did not display any activity toward any cell line tested. None of the compounds except compound 8 was cytotoxic toward PC-3. Compounds 4 and 8 showed the highest cytotoxic activity against the MCF-7 and MDA-MB-231 cell lines. Because compounds 3, 6, and 9 have similar half-maximal inhibitory concentration values against cancer cells and normal cells, these compounds displayed poor selectivity between cancer and normal cells. More importantly, it was observed that compound 5 acts differently toward different types of cell lines. For example, it displays lower cytotoxicity against the WI-38 normal cell line than it does against the MDA-MB-231 cell line. 相似文献
127.
First-principles calculations including dispersion correction are carried out to investigate pristine and Na-decorated graphene-like BC3 (h-BC3) for their application as methane storage materials. Structural optimization shows that the methane is physisorbed on the pristine sheet via van der Waals forces with adsorption energy of ?2.7 kcal/mol. It was found that unlike the pristine graphene, sodium decorated sheet can effectively interact with the CH4 molecule, so that each metal atom bound on sheet may adsorb up to four CH4. Furthermore, no bond dissociation was observed for the adsorption of CH4 on Na-decorated h-BC3, which means that decorated sheet can act as a storage device for methane safety storage. The results indicate that decoration of the Na atom on surface of sheet induces significant changes in electronic properties of the sheet and its E g is unchanged after adsorption of CH4 molecules. Theoretical methane storage capacity of Na-decorated BC3 nanosheet could approach 18.1 wt%. 相似文献
128.
In this study, a novel and eco‐friendly synthesis of benzochromenopyrimidines catalyzed by phosphotugstic acid immobilized on aminated multiwalled carbon nanotubes (MWCNTs@NHBut/PTA) is reported. New solid acid catalyst was prepared through a simple process with good percentage of organo metallic groups and characterized with FTIR, TEM, SEM, EDX and TGA techniques. Reusable catalytic system provides a convenient, safe and green pathway to generate a variety of benzochromenopyrimidines under mild conditions. 相似文献
129.
AbstractIt is well known that when a ring R satisfies ACC on right annihilators of elements, then the right singular ideal of R is nil, in this case, we say R is right nil-singular. Many classes of rings whose singular ideals are nil, but do not satisfy the ACC on right annihilators, are presented and the behavior of them is investigated with respect to various constructions, in particular skew polynomial rings and triangular matrix rings. The class of right nil-singular rings contains π-regular rings and is closed under direct sums. Examples are provided to explain and delimit our results. 相似文献
130.
Ahmadi Behrooz Golneshan Ali Akbar Arasteh Hossein Karimipour Arash Bach Quang-Vu 《Journal of Thermal Analysis and Calorimetry》2020,141(1):495-510
Journal of Thermal Analysis and Calorimetry - In this study, the numerical analysis of energy and exergy has been performed for a gas turbine cycle coupled with an ORC cycle. Validation of current... 相似文献