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排序方式: 共有199条查询结果,搜索用时 15 毫秒
21.
In this paper, the water waves problem for uneven bottoms in a highly nonlinear regime is studied. It is well known that, for such regimes, a generalization of the Boussinesq equations called the Green–Naghdi equations can be derived and justified when the bottom is variable (Lannes and Bonneton in Phys Fluids 21, 2009). Moreover, the Green–Naghdi and Boussinesq equations are fully nonlinear and dispersive systems. We derive here new linear asymptotic models of the Green–Naghdi and Boussinesq equations so that they have the same accuracy as the standard equations. We solve explicitly the new linear models and numerically validate the results. 相似文献
22.
Tlili Iskander Hamadneh Nawaf N. Khan Waqar A. Atawneh Samer 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1899-1912
Journal of Thermal Analysis and Calorimetry - This study will focus on the first- and second-law analyses of MHD Couette–Poiseuille flow of water-based nanofluids in a rotating permeable... 相似文献
23.
Racha El Debs Maguy Abi Jaoudé Nicolas Morin Cécile Miege Jérôme Randon 《Journal of separation science》2011,34(15):1805-1810
In recent years, metal oxides such as titania have been commercially available as chromatographic beds that can potentially be used to achieve novel separations of polar compounds. For example β blockers, which are more often encountered in environmental sciences, have a wide range of polarity, and their basic character leads to difficult sample treatment and separation on conventional silica‐based sorbents. The contribution of titania to the selective analysis of nine β blockers was evaluated in terms of retention mechanisms observed in hydrophilic interaction LC using acetonitrile/water mobile phases with various additives. The mobile phase additives enabled to control the β blocker charge as well as the titania surface charge. Depending on their respective ionic state, various retention mechanisms were identified at low water contents (<40%), including mainly adsorption mixed with hydrophilic interaction LC partition, ion exchange and ion exclusion. An unexpected retention was also observed for high water content and high pH, changing the selectivity of the support. 相似文献
24.
Ahmed AL-Osta Bushra Saleh Samer Vijaykumar V. Jadhav Umesh T. Nakate Rajaram S. Mane Mu. Naushad 《Journal of Solid State Electrochemistry》2017,21(9):2609-2614
Present work deals with a two-step synthesis and electrochemical properties of nickel oxide @copper oxide@copper (NiO@CuO@Cu) bilayered electrode. In the first step, anodization (40 V for 25 min) of Cu foil has been carried out for forming Cu-hydroxide@Cu which when annealed at 300 °C for 1 h produces CuO@Cu. In the second step, Ni-hydroxide is deposited onto CuO@Cu by applying current density of 0.03 A/cm2 for 3 min which when re-annealed at 300 °C for 1 h gives out NiO@CuO@Cu bilayered electrode. Obtained NiO@CuO@Cu bilayered electrode demonstrates separate CuO and NiO phases. The electrochemical properties have obtained using cyclic voltammetry, galvonostatic charge-discharge, and Nyquist plot measurements that reveal an importance of NiO@CuO@Cu as a potential electrode material in the electrochemical supercapacitor application with 58.14, 51.25, and 4.73 F g?1 values in 0.5 M, NaOH, KOH, and Na2SO4 electrolytes, respectively, measured at 2 mVs?1 scan rate. 相似文献
25.
Douglas R. Bey 《School science and mathematics》1972,72(9):810-810
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B. Blank A. Bey I. Matea J. Souin L. Audirac M. J. G. Borge G. Canchel P. Delahaye F. Delalee C. -E. Demonchy R. Domínguez-Reyes L. M. Fraile J. Giovinazzo Tran Trong Hui J. Huikari D. Lunney F. Munoz J. -L. Pedroza C. Plaisir L. Serani S. Sturm O. Tengblad F. Wenander 《The European Physical Journal A - Hadrons and Nuclei》2010,44(3):363-372
The half-lives of 38Ca and 39Ca have been measured at ISOLDE of CERN. The REXTRAP facility was used to prepare ultra-clean samples of radioactive nuclei for precision decay spectroscopy. 38Ca is one of the T z = - 1 , 0+ $ \rightarrow$ 0+ $ \beta$ -emitting nuclides used to determine the vector coupling constant of the weak interaction and the Vud quark-mixing matrix element. The result obtained, T 1/2 = 443.8(19) ms, is four times more precise than the average of previous measurements. For 39Ca , a half-life of T 1/2 = 860.7(10) ms is obtained, a result in agreement with the average value from the literature. 相似文献
29.
Aad G Abbott B Abdallah J Abdelalim AA Abdesselam A Abdinov O Abi B Abolins M Abramowicz H Abreu H Acerbi E Acharya BS Ackers M Adams DL Addy TN Adelman J Aderholz M Adomeit S Adragna P Adye T Aefsky S Aguilar-Saavedra JA Aharrouche M Ahlen SP Ahles F Ahmad A Ahsan M Aielli G Akdogan T Akesson TP Akimoto G Akimov AV Alam MS Alam MA Albrand S Aleksa M Aleksandrov IN Aleppo M Alessandria F Alexa C Alexander G Alexandre G Alexopoulos T Alhroob M Aliev M Alimonti G Alison J Aliyev M Allport PP 《Physical review letters》2010,105(25):252303
By using the ATLAS detector, observations have been made of a centrality-dependent dijet asymmetry in the collisions of lead ions at the Large Hadron Collider. In a sample of lead-lead events with a per-nucleon center of mass energy of 2.76 TeV, selected with a minimum bias trigger, jets are reconstructed in fine-grained, longitudinally segmented electromagnetic and hadronic calorimeters. The transverse energies of dijets in opposite hemispheres are observed to become systematically more unbalanced with increasing event centrality leading to a large number of events which contain highly asymmetric dijets. This is the first observation of an enhancement of events with such large dijet asymmetries, not observed in proton-proton collisions, which may point to an interpretation in terms of strong jet energy loss in a hot, dense medium. 相似文献
30.
We prove that in a tournament of odd order , the number of antidirected Hamiltonian paths starting with a forward arc and the number of Hamiltonian circuits have the same parity. 相似文献