排序方式: 共有41条查询结果,搜索用时 15 毫秒
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Niloufar Afzali Reihaneh Kardanpour Farnaz Zadehahmadi Shahram Tangestaninejad Majid Moghadam Valiollah Mirkhani Adam Mechler Iraj Mohammadpoor‐Baltork Mehrnaz Bahadori 《应用有机金属化学》2019,33(11)
A novel heterogeneous nanocatalyst was established by supporting molybdenum (VI) on Zr6 nodes in the structure of the well‐known UiO‐66 metal–organic framework (MOF). The structure of the UiO‐66 before and after Mo (VI) immobilization was confirmed with XRD, DR‐FTIR and UV–vis spectroscopy, and the presence and amount of Mo (VI) was identified by X‐ray photoelectron spectroscopy and inductively coupled plasma atomic emission spectroscopy. TEM imaging confirmed the absence of Mo clusters on the MOF surface, while SEM confirmed that the appearance of the MOF has not changed upon immobilizing the Mo (VI) catalyst. BET adsorption measurements were used to confirm the porosity of the catalyst. The catalytic activity of this heterogeneous catalyst was investigated in oxidation of sulfides with H2O2 in acetonitrile and oxidative desulfurization of dibenzothiophene. Easy work up, convenient and steady reuse and high activity and selectivity are prominent properties of this new hybrid material. 相似文献
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In the present work, dispersive liquid-liquid microextraction based on solidification of floating organic drop was developed as a simple and rapid technique for separation of silver ions from aqueous samples. In this technique, 700 μL 0.02% of 5-(4'-dimethylamino benzyliden)-rhodanine (chelating agent) was added into the 10 mL analyte sample in a test tube and 30.0 μL 1-undecanol (extraction solvent) was injected shortly thereafter. The test tubes were sonicated, centrifuged and then some effective parameters on extraction and complex formation, such as type and volume of extraction and disperser solvent, pH, the amount of chelating agent and extraction time were optimized. The effect of the interfering ions on the analytes recovery was also investigated. The calibration graph was linear in the range of 0.10-10.0 ng mL(-1) with detection limit of 0.056 ng mL(-1) (n=8). The relative standard deviation (RSD) was ±4.3% (n=8, C=5.0 ng mL(-1)) and the enrichment factor was 250.0. The proposed method was applied for extraction and determination of silver in different water samples. 相似文献
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H. Nazemiyeh F. Bahadori A. Delazar M. Ay G. Topcu U. Kolak L. Nahar A. A. Auzie S. D. Sarker 《Chemistry of Natural Compounds》2008,44(2):174-177
Reversed-phase preparative HPLC purification of the methanol (MeOH) extract of the aerial parts of Erica arborea resulted in the isolation of a new flavonoid glycoside, tricetin 4′-O-α-L-rhamnopyranoside, together with the known flavonoid, isorhamnetin 3-O-α-L-rhamnopyranoside. The structures of these compounds were determined by spectroscopic means. The antioxidant properties
of these compounds were assessed by the DPPH assay.
Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 138–140, March–April, 2008. 相似文献
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In this study,the three dimensional nanoscale organization in the photoactive layers of poly(3-hexylthiophene) (P3HT) and a methanofullerene derivative (PCBM) is revealed by transmission electron tomography.After annealing treatment,either at elevated temperature or during slow solvent evaporation,nanoscale interpenetrating networks are formed with high crystalline order and favorable concentration gradients of both components through the thickness of the photoactive layer.Such a tailored morphology acco... 相似文献
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A novel correlation for estimation of hydrate forming condition of natural gases 总被引:1,自引:0,他引:1 下载免费PDF全文
An inherent problem with natural gas production or transmission is the formation of gas hydrates, which can lead to safety hazards to production/
transportation systems and to substantial economic risks. Therefore, an understanding of conditions where hydrates form is necessary to
overcome hydrate related issues. Over the years, several models requiring more complicated and longer computations have been proposed for
the prediction of hydrate formation conditions of natural gases. For these reasons, it is essential to develop a reliable and simple-to-use method
for oil and gas practitioners. The purpose of this study is to formulate a novel empirical correlation for rapid estimation of hydrate formation
condition of sweet natural gases. The developed correlation holds for wide range of temperatures (265–298 K), pressures (1200 to 40000 kPa)
and molecular weights (16−29). New proposed correlation shows consistently accurate results across proposed pressure, temperature and
molecular weight ranges. This consistency could not be matched by any of the widely accepted existing correlations within the investigated
range. For all conditions, new correlation showed average absolute deviation to be less than 0.2% and provided much better results than the
widely accepted existing correlations. 相似文献
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Farimani MM Taheri S Ebrahimi SN Bahadori MB Khavasi HR Zimmermann S Brun R Hamburger M 《Organic letters》2012,14(1):166-169
Hydrangenone, a new heptacyclic isoprenoid with a 6/7/6/5/5 membered carbon ring skeleton, was isolated from the aerial parts of Salvia hydrangea. The structure was established by extensive NMR spectroscopic methods. The relative and absolute configuration of 1 was assigned by NOESY and X-ray crystallographic analysis and by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Compound 1 showed in vitro antiplasmodial activity, with an IC(50) value of 1.4 μM against P. falciparum. A plausible biosynthetic pathway of 1 was also proposed. 相似文献
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S.S. Penner C.P. Wang M.Y. Bahadori 《Journal of Quantitative Spectroscopy & Radiative Transfer》1985,33(3):293-295
Selected developing laser techniques for potential applications to flames with particulate loading are briefly described. 相似文献
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Alireza Bahadori Saeid Mokhatab Brian F. Towlera 《天然气化学杂志》2007,16(4):349-353
Natural gases containing sour components exhibit different gas compressibility factor(Z) behavior than do sweet gases.Therefore,a new accurate method should be developed to account for these differences.Several methods are available today for calculating the Z-factor from an cquation of state. However,these equations are more complex than the foregoing correlations,involving a large number of parameters,which require more complicated and longer computations.The aim of this study is to develop a simplified calculation method for a rapid estimating Z-factor for sour natural gases containing as much as 90% total acid gas.In this article,two new correlations are first presented for calculating the pseudo- critical pressure and temperature of the gas mixture as a function of the gas specific gravity.Then,a simple correlation on the basis of the standard gas compressibility factor chart is introduced for a quick estimation of sweet gases' compressibility factor as a function of reduced pressure and temperature.Finally,a new corrective term related to the mole fractions of carbon dioxide and hydrogen sulfide is developed. 相似文献
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