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51.
We reply to the charges by K.H. Yang in his paper “Gauge invariance and experimental processes”. 相似文献
52.
53.
The dehydrogenation of the known 3-methyl-5,8-dihydropyrazolo[1,2-a]pyridazin-1-one (2) to the ten π electron heteroaromatic 3-methylpyrazolo[1,2-a]pyridazin-1-one ( 3 ) is reported. Conversions of the pyrazolone 2 to the pyrazoloselenone 6 via the chloropyrazolium chloride 7 , and of pyrazolones 2 and 3 and pyrazoloselenone 6 into the corresponding O or Se ethyl pyrazolium fluoroborates 5, 4 , and 8 by triethyloxonium fluoroborate are also described. 相似文献
54.
The momentum transfer to absorbing particles is derived from the Lorentz force density without prior assumption of the momentum of light in media. We develop a view of momentum conservation rooted in the stress tensor formalism that is based on the separation of momentum contributions to bound and free currents and charges consistent with the Lorentz force density. This is in contrast with the usual separation of material and field contributions. The theory is applied to predict a decrease in optical momentum transfer to Mie particles due to absorption, which contrasts the common intuition based on the scattering and absorption by Rayleigh particles. 相似文献
55.
Huynh Le Thanh Nguyen Tran Thi Thuy Dung Nguyen Hoang Hai Au Nguyen Thi Thu Trang Tran Van Man Grag Akhil Le My Loan Phung 《Journal of Solid State Electrochemistry》2018,22(7):2247-2254
Journal of Solid State Electrochemistry - Olivine LiFePO4 (LFP) is a promising cathode material for high-rated lithium-ion batteries. However, olivine faced a severe disadvantage of low... 相似文献
56.
We demonstrate 60-fs pulses with an average output power of 84 mW from a diode-pumped Nd:glass laser mode locked by a low-finesse antiresonant Fabry-Perot saturable absorber (A-FPSA). The mode-locked spectrum spreads over most of the available Nd:glass fluorescence bandwidth. At increased pulse energy fluence or decreased negative group-velocity dispersion, multiple pulsing was observed. We experimentally characterize this behavior, which can be explained by the saturation behavior of the A-FPSA and the limited available gain bandwidth. These considerations are significant for the design of saturable absorbers to achieve stable passive mode locking. 相似文献
57.
Lydia Außenhofer 《Mathematische Zeitschrift》2007,257(2):231-237
We construct a quotient group of an uncountable product of integers which is not Pontryagin reflexive. 相似文献
58.
On analyzing the topological structures of the three types of tetrahedral fullerenes (which consist only of triangles and
hexagons), (1) C
n
(T
d
,n=12h
2; h=1,2,…), (2) C
n
(T
d
,n=4h
2;h=1,2,…), and (3) C
n
(T,n=4(h
2+hk+k
2);h>k,h,k=1,2,…), we have obtained theoretically the Infrared and Raman active modes by means of the derived formulas for the decomposition
of their nuclear motions into irreducible representations, and the 13C NMR spectra with natural abundance for 13C by using the distribution functions for all of the tetrahedral (T
d
and T) fullerenes, respectively.
Received: 25 May 1998 / Accepted: 30 July 1998 / Published online: 23 November 1998 相似文献
59.
On the bases of the topological structures of the three big classes of icosahedral fullerenes: (1) Cn(Ih, n=60h2; h=1, 2,…), (2) Cn(Ih, n=20h2; h=1, 2,…), and (3) Cn(I, n=20(h2+hk+k2), h>k; h, k=1, 2,…), we derived formulas for the decomposition of their nuclear motions into irreducible representations. Hence, we obtained the infrared and Raman active modes for all of the icosahedral (Ih and I) fullerenes theoretically. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 66 : 113–117, 1998 相似文献
60.