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371.
372.
The present paper deals with the analysis of a non-oxide type of vertical-cavity surface-emitting laser (VCSEL) for operation
at 850 nm. The modeling and characterization of the VCSEL is presented in the context of design considerations. Efforts are
made to emphasize the behavioral features of the proposed VCSEL, in view of the analytical investigation, which has been performed
through a series of simulations for various relevant parameters that are vital for the determination of the VCSEL characteristics.
Some of these parameters are the intensity and refractive-index distributions, gain response, spontaneous emission, material
gain variations, etc. The results obtained are compared with the oxide-confined VCSEL. It is observed that the proposed model
of the VCSEL is suitable at the operating wavelength of 850 nm. 相似文献
373.
374.
Hiroki Sano Tamotsu Izumida Ken-Ichi Mitani Tomoyoshi Ohwada Kichi-Suke Saito 《Central European Journal of Mathematics》2014,12(5):778-786
In [Mineno K., Nakamura Y., Ohwada T., Characterization of the intermediate values of the triangle inequality, Math. Inequal. Appl., 2012, 15(4), 1019–1035] there was established a norm inequality which characterizes all intermediate values of the triangle inequality, i.e. C n that satisfy 0 ≤ C n ≤ Σ j=1 n ‖x j ‖ ? ‖Σ j=1 n x j ‖, x 1,...,x n ∈ X. Here we study when this norm inequality attains equality in strictly convex Banach spaces. 相似文献
375.
Sen R Koner S Bhattacharjee A Kusz J Miyashita Y Okamoto K 《Dalton transactions (Cambridge, England : 2003)》2011,40(26):6952-6960
[Ru(bpy)(3)](2+) (bpy = 2,2'-bipyridine) ions were entrapped into the cavities of two-dimensional anionic sheet-like coordination polymeric networks of [M(dca)(3)](-) (dca = dicyanamide; M = Mn(II) and Fe(II)). The prepared compounds, {[Ru(bpy)(3)][Mn(dca)(3)](2)}(n) (1) and {[Ru(bpy)(3)][Fe(dca)(3)](2)}(n) (2), were structurally characterized by X-ray single crystal analysis. The spectroscopic properties of the [Ru(bpy)(3)](2+) ion dramatically changed on its entrapment in [M(dca)(3)](-). The [Ru(bpy)(3)](2+) moiety present in 1 and 2 exhibits novel dual photo-emission at room temperature. 相似文献
376.
Katsuo Mitani 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(6):1033-1049
The dyad and triad tacticities of polypropylenes were determined quantitatively with the aid of a computer form the 100-MHz proton magnetic resonance spectra in o-dichlorobenzene solution at 165[ddot]C. The contents of tactic dyad and traid evaluated from the 100-MHz PMR spectra are in fair agreement with the values determined from the 220-MHz PMR and 13C-(1H) spectra, respectively. The fraction soluble in boiling ethyl ether of polymer prepared with the Ti(O-n-Bu)Cl3-AlEt2 Cl catalyst shows a character of stereorandomness, and the ethyl ether-soluble portion of polymer polymerized with the TiCl3-AlEt2 Cl catalyst has a character of stereoblock sequence. Furthermore, by IR analysis, it has become apparent that the former has a (CH2)2 group formed by two propylene units in a tail-to-tail arrangement. 相似文献
377.
378.
Asymmetric trans-addition reactions of simple olefins have been performed by using optically active 2-selenobinaphthyls 1 , 2a–g. Introduction of an amide group at the 2′-position in the binaphthyl skeleton enhances considerably the diastereomeric excess (de) of the asymmetric methoxyselenenylation. In the case of trans-olefins, introduction of another chiral center in the amide group further enhances the de due to double stereodifferentiation between the (R)-binaphthyl skeleton and the chiral amide group introduced at the 2′-position in the binaphthyl skeleton. The use of chiral nucleophiles is also effective to enhance the de for symmetrical cis-olefins. 相似文献