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991.
992.
993.
In this Note we establish an interior Lp-type estimate for the solutions of Maxwell's equations with source term in a domain filled with two different materials separated by a interface. Due to the singularity of the dielectric permittivity, the usual elliptic estimates cannot be applied directly. A special curl–div decomposition is introduced for the electric field to reduce the problem to an elliptic equation in divergence form with discontinuous coefficients. The potential theory analysis and the jump condition lead to the Lp estimates which are superior to the straightforward Nash–Moser estimates. The reduction procedure is expected to be useful for numerical simulation. Such an estimate is crucial for solving nonlinear Maxwell's equations that arise for example in the modeling of nonlinear optics. To cite this article: G. Bao et al., C. R. Acad. Sci. Paris, Ser. I 337 (2003). 相似文献
994.
In the strain field measurements, especially in large strain field measurements, the correlation coefficient values obtained by the digital speckle correlation method are usually very low due to the relative pixel movement of the subset. The measuring error, therefore, is increased. A primary method, that is called compensation algorithm, is introduced for improving the correlation coefficient. A flow scheme with the compensation algorithm of our software is developed and some improved techniques for reducing the calculation time and error are discussed in the paper. After obtaining a set of displacement data with high correlation coefficient, a de-noise wavelet processing is adopted. It is obvious that the measuring accuracy of the strain field is better then before. A strain field of testing experiment is performed with this compensation technique. The correlation coefficients can increase from 0.70 to 0.99, which will be of much benefit for the improvements of the measuring accuracy. 相似文献
995.
In this paper, we study the stability of a class of recursive sequence under certain conditions. 相似文献
996.
电磁场的不变量的求证方法讨论 总被引:1,自引:0,他引:1
用几种不同的方法对电磁场的不变量进行了求证和讨论,指出每种方法都可以归结为利用四维协变张量元素本身构造出洛伦兹不变量。 相似文献
997.
本文给出了Fuzzy拓扑线性空间的若干特征刻划,简化了判断Fuzzy拓扑线性空间的条件,研究了Fuzzy拓扑线性空间的层次结构,揭示了Fuzzy拓扑线性空间与分明拓扑线性空间的内在联系,得到了Fuzzy拓扑线性空间的“平移不变性”与“局部凸性”都是可截性质。 相似文献
998.
New thermotropic side chain liquid crystalline ionomers (LCIs), containing 4-(4-allyloxybenzyloxy)-4'-alkoxybiphenyl (IM) as mesogenic unit and allyltriethylammonium bromide (ATAB) as non-mesogenic unit, were synthesized by graft copolymerization upon polymethylhydrosiloxane. The chemical structures of the polymers were confirmed by IR spectroscopy. Differential scanning calorimetry (DSC) was used to measure the thermal properties of these polymers; the mesogenic properties were characterized by polarizing optical micrography, DSC and X-ray diffraction. The influence of the alkoxy chain length on the clearing temperatures of the ionomers is clearly shown in an odd-even effect, similar to other side chain liquid crystal polymers. The mesomorphic behaviour of the ionomers is compared with that of isomeric ionomers synthesized in previous work. The results demonstrate that the phase behaviour of the two series of isomeric ionomers is similar, but with the difference that the melting temperature of ionomers with biphenyl located at the end of the mesogen is higher than for ionomers with biphenyl located at the middle of the mesogen. The latter are more useful for smectic orientational order than the former. 相似文献
999.
Anunoniaisasignificantalkalinepollutantintheatmosphere.AInInoniaeInittedintothetroposphereisreadilytraPpedbyacidicclouddropletSanditneutralizestheacidityofthedropletStoformammoniumsaltS.Therefore,thedetendnationoftheanunoniumioninwetdepositionisveryimportantinatmosphericchemistry,andthereisaneedforasimPleandrapidmethodforthedetendnationofNfu .Variousdetectionmethodsandtechniquesareusedfordetendninganunoniaorammoniumion,suchasionchromatography',ion-selectiveeIectrode',BLMselectrochendcalse… 相似文献
1000.
Yan Yan Liu Sheng Qin Xia Zhang Hua Zeng Rui Qiao Xue Song Wang Bao Wen Zhang 《中国化学快报》2008,19(2):157-160
A new hypocrellin B (HB) derivative bearing a bispyrrolecarboxamide-containing side chain was synthesized, which presents improved absorptivity in phototherapeufic window than HB and affinity feature towards dsDNA. 相似文献