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Nonlinear Dynamics - We establish a nonlinear non-conservative mathematical framework for the acoustic-electro-elastic dynamics of the response of a piezoelectric disk to high-level acoustic... 相似文献
93.
Agabekov V. E. Kazak N. S. Belyi V. N. Kurilkina S. N. Ryzhevich A. A. Shahab S. N. Mitkovets A. I. Mashchenko A. G. 《Journal of Applied Spectroscopy》2021,88(4):816-824
Journal of Applied Spectroscopy - A polarizing light beam splitter is created in the form of two Dove prisms of BK7 glass with a multilayer thin-fi lm coating made of two periodic substructures... 相似文献
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Arash Rabbani Todor G. Baychev Shahab Ayatollahi Andrey P. Jivkov 《Transport in Porous Media》2017,116(1):143-161
This article describes experimental results and the numerical validation for multiphase, multicomponent evaporation in porous media 1d flow. We apply the model of Lindner et al. (Transp. Porous Media 112(2):313–332, 2016. doi: 10.1007/s11242-016-0646-6). The permeability of the porous medium is measured in an additional setup with a constant head permeameter to verify the validity of Darcy flow. The heat losses are considered in an analytical approach of correlating measured temperatures and heat inputs with enthalpies. A method of interpreting the experimental results is discussed to determine the phase state. We can show good qualitative agreement of the shift and position of the evaporation region when varying boundary conditions such as mass flux, concentration and heat input. 相似文献
97.
Karimi Zarchi Mohammad Ali Darbandizadeh Mohammad Abadi Seyed Shahab Addin 《Research on Chemical Intermediates》2019,45(5):2605-2639
Research on Chemical Intermediates - Facile and efficient protocols for some multicomponent coupling reactions such as the Suzuki reaction and synthesis of polyhydroquinoline and... 相似文献
98.
Sarkar D Sullivan S Joudaki S Amblard A Holz DE Cooray A 《Physical review letters》2008,100(24):241302
Our ignorance of dark energy is generally described by a two-parameter equation of state. In these approaches, a particular ad hoc functional form is assumed, and only two independent parameters are incorporated. We propose a model-independent, multiparameter approach to fitting dark energy and show that next-generation surveys will constrain the equation of state in three or more independent redshift bins to better than 10%. Future knowledge of dark energy will surpass two numbers (e.g., [w{0},w{1}] or [w{0},w{a}]), and we propose a more flexible approach to the analysis of present and future data. 相似文献
99.
Derakhshan S Kleinke KM Dashjav E Kleinke H 《Chemical communications (Cambridge, England)》2004,(21):2428-2429
HfMoSb4, isostructural with the isoelectronic NbSb2, exhibits nonmetallic properties, as predicted via electronic structure calculations made before the actual discovery of HfMoSb4. 相似文献
100.
Maryam Ganjikhah Shahab Shariati Elahe Bozorgzadeh 《Journal of the Iranian Chemical Society》2017,14(4):763-769
Formaldehyde is known as a highly toxic compound to humans and identified as a carcinogenic substance. In this study, Hantzsch reaction was utilized for the derivatization of trace amounts of formaldehyde in aqueous samples with acetylacetone in the presence of ammonia to form an extractable colored product named 3,5-diacetyl 1,4-dihydrolutidine (DDL) and its further extraction using two-phase hollow fiber liquid-phase microextraction. The main experimental variables affecting the extraction performance were investigated and optimized. Under the optimum conditions (sample volume 12 mL; reaction temperature 70 °C; ammonium acetate buffer solution 4 mL 0.1 mol L?1; acetylacetone 5 mL 0.15 mol L?1; solvent octanol, salt concentration 20% (w/v) NaCl; pH of donor phase 7.0; stirring speed 400 rpm and extraction time 30 min), the linear dynamic range, limit of detection (LOD as 3S b/m) and relative standard deviation (RSD %) of the proposed method were obtained as 5–250 μg L?1 (r 2 = 0.9979), 3.6 μg L?1 and 2.5%, respectively. Finally, the applicability of the proposed method was examined, and very good results were obtained. The results confirmed the applicability of the proposed method as a versatile, low-cost and sensitive preconcentration method for determination of low concentrations of formaldehyde in aqueous solutions. 相似文献