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81.
Borisova T. D. Blagoveshchenskaya N. F. Kalishin A. S. Häggström M. I. Rietveld M. T. 《Radiophysics and Quantum Electronics》2020,62(12):793-806
Radiophysics and Quantum Electronics - We present the results of experimental studies of the generation peculiarities and features of the Langmuir and ion–acoustic turbulence in the F region... 相似文献
82.
Adeniyi Adebayo A. Akintayo Cecilia O. Akintayo Emmanuel T. Conradie Jeanet 《Structural chemistry》2020,31(3):861-875
Structural Chemistry - Natural-based polyols are seen by polyurethane industries as an alternative to the petroleum-based polyols because of increasing challenges due to the oil crisis and global... 相似文献
83.
Yunnikova L. P. Akentʼeva T. A. Likhareva Yu. E. 《Russian Journal of Organic Chemistry》2020,56(12):2244-2247
Russian Journal of Organic Chemistry - Reactions of tropylium tetrafluoroborate with 4-nitrobenzohydrazide, semicarbazide hydrochloride, thiosemicarbazide, and N-benzylurea afforded the... 相似文献
84.
This paper investigates the unsteady stagnation-point flow and heat transfer over a moving plate with mass transfer,which is also an exact solution to the unsteady Navier-Stokes(NS)equations.The boundary layer energy equation is solved with the closed form solutions for prescribed wall temperature and prescribed wall heat flux conditions.The wall temperature and heat flux have power dependence on both time and spatial distance.The solution domain,the velocity distribution,the flow field,and the temperature distribution in the fluids are studied for different controlling parameters.These parameters include the Prandtl number,the mass transfer parameter at the wall,the wall moving parameter,the time power index,and the spatial power index.It is found that two solution branches exist for certain combinations of the controlling parameters for the flow and heat transfer problems.The heat transfer solutions are given by the confluent hypergeometric function of the first kind,which can be simplified into the incomplete gamma functions for special conditions.The wall heat flux and temperature profiles show very complicated variation behaviors.The wall heat flux can have multiple poles under certain given controlling parameters,and the temperature can have significant oscillations with overshoot and negative values in the boundary layers.The relationship between the number of poles in the wall heat flux and the number of zero-crossing points is identified.The difference in the results of the prescribed wall temperature case and the prescribed wall heat flux case is analyzed.Results given in this paper provide a rare closed form analytical solution to the entire unsteady NS equations,which can be used as a benchmark problem for numerical code validation. 相似文献
85.
Dr. Haoxuan Li Haifei Wen Dr. Zhijun Zhang Dr. Nan Song Prof. Ryan T. K. Kwok Prof. Jacky W. Y. Lam Prof. Lei Wang Prof. Dong Wang Prof. Ben Zhong Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20551-20555
Using reverse thinking of the aggregation-induced emission (AIE) principle, we demonstrate an ingenious and universal protocol for amplifying molecular motions to boost photothermal efficiency of fibers. Core–shell nanofibers having the olive oil solution of AIE-active molecules as the core surrounded by PVDF-HFP shell were constructed by coaxial electrospinning. The molecularly dissolved state of AIE-active molecules allows them to freely rotate and/or vibrate in nanofibers upon photoexcitation and thus significantly elevates the proportion of non-radiative energy dissipation, affording impressive heat-generating efficiency. Photothermal evaluation shows that the core–shell nanofibers with excellent durability can reach up to 22.36 % of photothermal conversion efficiency, which is 26-fold as the non-core–shell counterpart. Such a core–shell fiber can be used for photothermal textiles and solar steam generation induced by natural sunlight with green and carbon-zero emission. 相似文献
86.
87.
N. Stallkamp S. Ringleb B. Arndt M. Kiffer S. Kumar T. Morgenroth G.G. Paulus W. Quint Th. Stöhlker M. Vogel 《X射线光谱测定》2020,49(1):188-191
Detailed investigations of laser–ion interactions require well-defined ion targets and detection techniques for high-sensitivity measurements of reaction educts and products. To this end, we have designed and built the High-Intensity Laser-Ion Trap Experiment Penning trap setup, which features various ion-target preparation techniques including selection, cooling, compression, and positioning as well as destructive and non-destructive measurement techniques to determine the number of stored ions for all charge states individually and simultaneously. We have recently performed first commissioning experiments of ion deceleration and dynamic ion capture with highly charged ion bunches from an electron beam ion source. We have characterized our single-pass non-destructive ion counter in detail and were able to determine the ion velocity as well as the number of ions from the signals acquired. 相似文献
88.
89.
Optics and Spectroscopy - A new method for studying the conformational state of a protein and its interaction with a solvent has been developed. The method is based on measuring the refractive... 相似文献
90.
Optics and Spectroscopy - The design of neutral nonpolarizing interference systems formed on the face of one of the two prisms that are components of an optical element in the form of a cube is... 相似文献