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101.
102.
We investigate the scattering of a polychromatic plane light wave incident upon an anisotropic particle. It is different from light wave scattered by an isotropic particle that the frequency shifts of spectral lines will be induced by the rotation of the anisotropic particle. The analytical expression for the spectrum of the scattered field is derived and numerical examples are also illustrated. We suggest an application that the angular speed of rotation of the anisotropic scatterer can be scaled by measurement of the spectrum of the scattered field. 相似文献
103.
J-semicommutative环的性质 总被引:1,自引:0,他引:1
环冗称为J—semicommutative若对任意B,b∈R由ab=0可以推得aRb∈J(R),这里J(R)是环R的Jacobson根.环R是J—semicommutative环当且仅当它的平凡扩张是J—semicommutative环当且仅当它的Don'oh扩张是J—semicommutative环当且仅当它的Nagata扩张是,一semicommutative环当且仅当它的幂级数环是J—semicommutative环.若R/J(R)是semicommutative环,则可得到R是J-semicommutative环.本文进一步论证了如果,是环月的一个幂零理想,且R/I是J—semicommutative环,则R也是J-semicommutative环最后给出了J—semicommutative环与其他一些常见环的联系 相似文献
104.
在G-度量空间的框架下,利用自映象对的非相容性和(Ag)型R-弱交换性条件,在既不要求空间的完备性,也不要求映象连续的条件下,建立了一类?-压缩条件下的4个映象的几个新的公共不动点定理,此定理在很大程度上改进和发展了已有文献的相关结果. 相似文献
105.
Wenchang Chu 《Results in Mathematics》2012,61(3-4):209-221
By means of Abel’s lemma on summation by parts, we derive several infinite series identities, which involve the classical harmonic numbers and their variants. 相似文献
106.
Xuxin Yang Weibing Wang Jianhua Shen 《Journal of Applied Mathematics and Computing》2012,40(1-2):511-528
We consider the existence of multiple positive solutions of the singular boundary value problem for the Sturm-Liouville equation with impulses on the half line. By applying the fixed-point index theorem of a cone map, existence and multiplicity results about positive solutions are obtained. Our results improve and generalize some well-known results. An example is presented to demonstrate applications of our main results. 相似文献
107.
Using first‐principles calculations, we investigate the chemical functionalizations of beryllium monoxide (BeO) nanostructures by the fluorine and hydrogen atoms. We find that the hydrogenation weakens the Be–O bonds and causes the instability of semihydrogenated nanosheets, while the fluorination is energetically favorable and forms a stable semifluorinated conformation. More importantly, the semifluorinated BeO sheet exhibits an intrinsic half‐metallic behavior, which is robust with a large half‐metal gap and a high Curie temperature above room temperature. By the same strategy of fluorination, the half‐metallicity can also be achieved in the one‐dimensional BeO nanotubes and nanoribbons. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
108.
利用相转移催化剂十六烷基三甲基溴化铵(CTMAB)催化的连二亚硫酸钠引发的苯酚衍生物与含氟碘代烷的氟烷基化反应, 合成了含氟烷基取代的酚类化合物. 研究了双酚A与含氟碘代烷的氟烷基化反应, 得到了一类重要的含氟单体, 即含氟烷基取代的双酚A衍生物. 通过改变含氟碘代烷与双酚A的摩尔比, 可以得到单取代、二取代和四取代的含氟烷基双酚A衍生物. 相似文献
109.
The interactions between solitoffs are extensively investigated. Besides the known solitoff fission and fusion interactions, two new types of solitoff interactions are discovered, named the solitoff reconnection and the solitoff annihilation. Taking the asymmetric Nizhnik--Novikov--Veselov equation as an illustrative system, five types of solitoff interactions are graphically revealed on the basis of the analytical solution obtained by the modified tanh function expansion method. 相似文献
110.
《Comptes Rendus de l'Académie des Sciences》2001,329(11):797-802
Extending the previous work by Chambon et al. [2] to the finite deformation regime, a local second gradient theory of plasticity for isotropic materials with microstructure is developed based on the multiplicative decomposition of the deformation gradient, the additive decomposition of the second deformation gradient and the principle of maximum dissipation. 相似文献