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351.
352.
Hamid Reza Mortaheb Babak Mokhtarani Nima Shafiee Ali Sharifi 《Journal of solution chemistry》2018,47(12):2007-2020
An experimental study on the isobaric vapor–liquid equilibria for the ternary system of acetone?+?methanol?+?1-methyl-3-octylimidazolium thiocyanate ([Omim][SCN]) as well as the two acetone?+?ionic liquid (IL) and methanol?+?IL binary systems was performed at 100 kPa using a recirculating still (VLE 602 Fischer apparatus). A low IL mole fraction of 0.027 was found to be sufficient break the azeotrope due to the high and specific interactions with acetone and methanol. The nonrandom two-liquid model was used to represent the experimental data. The results are compared with those in the literature for the same mixed solvent system using other ILs. 相似文献
353.
Babak Kaboudin Ali Zangooei Foad Kazemi Tsutomu Yokomatsu 《Tetrahedron letters》2018,59(11):1046-1049
A simple method is reported for the synthesis of alkylaminophenols in moderate to good yields via a three-component, catalyst-free decarboxylative coupling of proline with salicylaldehyde and boronic acids. 相似文献
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355.
A model updating methodology is proposed for calibration of nonlinear finite element (FE) models simulating the behavior of real-world complex civil structures subjected to seismic excitations. In the proposed methodology, parameters of hysteretic material models assigned to elements (or substructures) of a nonlinear FE model are updated by minimizing an objective function. The objective function used in this study is the misfit between the experimentally identified time-varying modal parameters of the structure and those of the FE model at selected time instances along the response time history. The time-varying modal parameters are estimated using the deterministic–stochastic subspace identification method which is an input–output system identification approach. The performance of the proposed updating method is evaluated through numerical and experimental applications on a large-scale three-story reinforced concrete frame with masonry infills. The test structure was subjected to seismic base excitations of increasing amplitude at a large outdoor shake-table. A nonlinear FE model of the test structure has been calibrated to match the time-varying modal parameters of the test structure identified from measured data during a seismic base excitation. The accuracy of the proposed nonlinear FE model updating procedure is quantified in numerical and experimental applications using different error metrics. The calibrated models predict the exact simulated response very accurately in the numerical application, while the updated models match the measured response reasonably well in the experimental application. 相似文献
356.
In this Letter, the concept of transmit array antenna enabling light concentration in the near-IR region is explored. As for the elements of the transmit array, concentric loop scatterers are chosen due to their design flexibility and potential for providing high phase variation by changing the dimensions of the loops. Periodic behaviors of the concentric loop elements are obtained by means of the finite-difference time-domain method. Using these results, a transmit array configuration is designed, and a focused beam at a desired distance is achieved. To model the electromagnetic fields of the finite array, the field equivalence principle and proper dyadic Green's functions are applied. 相似文献
357.
Jason M. Hogan David M. S. Johnson Susannah Dickerson Tim Kovachy Alex Sugarbaker Sheng-wey Chiow Peter W. Graham Mark A. Kasevich Babak Saif Surjeet Rajendran Philippe Bouyer Bernard D. Seery Lee Feinberg Ritva Keski-Kuha 《General Relativity and Gravitation》2011,43(7):1953-2009
We propose an atom interferometer gravitational wave detector in low Earth orbit (AGIS-LEO). Gravitational waves can be observed by comparing a pair of atom interferometers separated by a 30 km baseline. In the proposed configuration, one or three of these interferometer pairs are simultaneously operated through the use of two or three satellites in formation flight. The three satellite configuration allows for the increased suppression of multiple noise sources and for the detection of stochastic gravitational wave signals. The mission will offer a strain sensitivity of ${<10^{-18}/\sqrt{{\rm Hz}}}$ in the 50mHz?C10Hz frequency range, providing access to a rich scientific region with substantial discovery potential. This band is not currently addressed with the LIGO, VIRGO, or LISA instruments. We analyze systematic backgrounds that are relevant to the mission and discuss how they can be mitigated at the required levels. Some of these effects do not appear to have been considered previously in the context of atom interferometry, and we therefore expect that our analysis will be broadly relevant to atom interferometric precision measurements. Finally, we present a brief conceptual overview of shorter-baseline $({\lesssim100\,{\rm m}})$ atom interferometer configurations that could be deployed as proof-of-principle instruments on the International Space Station (AGIS-ISS) or an independent satellite. 相似文献
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359.
Babak Kaboudin Ramin Mostafalu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):776-780
Abstract A simple, efficient, and novel method has been developed for the phosphorylation of phenols. Treatment of phenols with a mixture of triethylphosphate/phosphorus pentoxide gives the corresponding phosphate derivatives in good yields. This method is easy, rapid, and offers good yields for the phosphorylation of phenols. The reaction of triethylphosphate with phosphorus pentoxide was also studied by variable-temperature 31P-NMR spectroscopy. 相似文献
360.
Karimi B Behzadnia H Rafiee M Vali H 《Chemical communications (Cambridge, England)》2012,48(22):2776-2778
A novel nano-fibrillated mesoporous carbon (IFMC) was found to be an effective modifier in combination with ionic liquid 1-octylpyridinum hexafluorophosphate (OPFP) as a binder to give impregnated graphite electrodes with outstanding electrochemical performances. 相似文献