Single-mode rib polymer waveguides and electro-optic polymer waveguide switches

Mode-matching and effective index methods are used to analyze single-mode operation of optical rib polymer waveguides. Their single-mode waveguiding conditions are determined. Single-mode rib waveguides fabricated from guest–host polyetherketone are presented. The estimated propagation loss of straight rib-waveguides is 0.7 dB/cm at 1.55 μm. Furthermore, by using the mode field-transfer matrix method, 2×2 and 4×4 polymer Mach–Zehnder interference switch operating at 1.55 μm wavelength has been designed based on optical multi-mode interference.     

Co-P非晶态合金电子性质和局域结构的理论研究

根据Co P非晶态合金结构的短程有序和结构中可能存在P -P相互作用的实验事实 ,选择了单磷原子簇模型ConP(n =1～ 5 )和双磷原子簇模型ConP2 (n =1～ 4 ) ,用密度泛函理论方法对其进行计算 .结果表明 ,在单磷Co2 P( 2 ) 、Co3 P( 1) 及Co4P( 2 ) 模型体系中 ,Co原子供给P原子电子 ,与电负性规则一致 ,同时Co和P之间具较强化学作用 ,可以形成稳定的原子簇 ;而在双磷和单磷原子簇Co5P( 1) 模型体系中 ,形成的原子簇不稳定 ,采用单磷Co2 P( 2 ) 、Co3 P( 1) 及Co4P( 2 ) 模型能较好地反映Co P非晶态合金的结构特点 .     

LOCAL WELL-POSEDNESS AND ILL-POSEDNESS ON THE EQUATION OF TYPE □u = uk((e)u)α

This paper undertakes a systematic treatment of the low regularity local wellposedness and ill-posedness theory in Hs andHs for semilinear wave equations with polynomial nonlinearity in u and (e)u. This ill-posed result concerns the focusing type equations with nonlinearity on u and (e)tu.     

Three-Step Predictor-Corrector of Exponential Fitting Method for Nonlinear Schroedinger Equations

We develop the three-step explicit and implicit schemes of exponential fitting methods. We use the three- step explicit exponential fitting scheme to predict an approximation, then use the three-step implicit exponential fitting scheme to correct this prediction. This combination is called the three-step predictor-corrector of exponential fitting method. The three-step predictor-corrector of exponential fitting method is applied to numerically compute the coupled nonlinear Schroedinger equation and the nonlinear Schroedinger equation with varying coefficients. The numerical results show that the scheme is highly accurate.     

An efficient one‐pot synthesis of novel pyrimidoquinoline derivatives under microwave irradiation without catalyst

A series of pyrimidoquinoline derivatives were synthesized through one‐pot condensation of 2,6‐diaminopyrimidin‐4‐one, aldehyde and cyclic a 1,3‐dicarbonyl compound in glycol under microwave irradiation without catalyst. The protocol in the absence of catalyst has the advantage of good yield (87‐95%), short reaction time (4‐7 min) and an environmentally friendly technique.     

激光晶体YAG中Er3+的辐射跃迁

本文讨论和分析了激光晶体YAG中Er3+离子的激光上能级的4S3/2、4I11/2和4I13/2辐射跃迁的有关因素。     

Blind Channel Identification Based on Noisy Observation by Stochastic Approximation Method

A stochastic approximation algorithm for estimating multichannel coefficients is proposed, and the estimate is proved to converge to the true parameters a.s. up-to a constant scaling factor. The estimate is updated after receiving each new observation, so the output data need not be collected in advance. The input signal is allowed to be dependent and the observation is allowed to be corrupted by noise, but no noise statistics are used in the estimation algorithm.     

ADSORBENTS USED IN THE CLEARANCE OF ENDOTOXIN

1.INTRODUCTION[()-227.3()]Endotoxinislipopolysaccharide(LPS)derivedfromthecellmembranesofgram-negativebacteria.Endotoxincancausefebrilereactionsinanimalswithsymptomsofhighfever,vasodilation,diarrheaandfetalshockwheninjectedeveninaverysmallamount[1].Iftheconcentrationofendotoxininpatients?bloodishighenoughitcancauseseveresepsis,whichisamajorcauseofdeathinpatientsandcontinuestohaveahighmortalitydespiteappropriatesurgery,potentantibiotic,andintensivesupportivetherapy[2~5].LipidAisthemaintox…     

Preparation and Selectivity of Molecularly Imprinted Polymer Coating on the Micro Pore Membrane of Polytetrafluoroethylene

In order to obtain mechanically stable membrane for practical application, the imprinted polymer was synthesized in the pores of polyfluoromembrane, the binding and transport ability of the membrane were studied.     

Distance riemannienne,théorème de Rademacher et inégalité de transport sur le groupe des lacets

In this Note, we shall consider the Riemannian distance on loop groups, which will be identified to one introduced by Hino and Ramirez [M. Hino, J.A. Ramirez, Small-time Gaussian behavior of symmetric diffusion semigroups, Ann. Probab. 31 (2003) 1254–1295]. A transportation cost inequality is established. To cite this article: S. Fang, J. Shao, C. R. Acad. Sci. Paris, Ser. I 341 (2005).