Hydrogen-bonded dimer of N,N′-(5-n-butyl-5-oxodibenzo[b,d]phosphole-3,7-diyl)bis(benzamide) dimethylformamide solvate

The structure of a large wing-span phosphine, in the oxide form, N,N-(5-n-butyl-5-oxodibenzo[b,d]phosphole-3,7-diyl)bis(benzamide), C₃₀H₂₇N₂O₃P, cocrystallized with dimethylformamide (DMF), C₃H₇NO, is reported. The title compound is crystallized in a triclinic system with cell dimensions of a = 10.295(8) b = 12.743(5) c = 13.239(6) Å, = 108.14(3), = 108.16(5), = 101.20(4)°, and V=1484.4(5) ų, and forms a hydrogen-bonded dimer via two hydrogen bond linkages of the P—O ··· H—N type involving one of the two amide groups.     

Synthesis and characterization of diphenylaminodiphenyl stryl based alternating copolymers

Diphenylaminobiphenylated stryl based alternating copolymers with phenyl or fluorene, which were expected to have a terphenylene vinylene backbone containing an (N,N‐diphenylamino)biphenyl pendant and a phenyl/fluorene/phenylene vinylene backbone containing an (N,N‐diphenylamino)biphenyl pendant, were synthesized by a Suzuki coupling reaction. The obtained copolymers were confirmed with various types of spectroscopy. The alternating copolymers showed good hole‐injection properties because of their low oxidation potential and good solubility and high thermal stability with a high glass‐transition temperature. The alternating copolymers showed blue emissions because of the adjusted conjugation lengths; the maximum wavelength was 460 nm for poly{4,4′‐biphenylene‐α‐[4″‐(N,N′‐diphenylamino)diphenyl]vinylene‐alt‐5‐(2′‐ethylhexyloxy)‐2‐methoxybenzene} and 487 nm for poly{4,4′‐biphenylene‐α‐[4″‐(N,N′‐diphenylamino)diphenyl] vinylene‐alt‐9,9‐dihexylfluorene}. The maximum brightness of indium tin oxide/poly(3,4‐ethylene dioxythiophene)/polymer/LiF/Al devices with poly{4,4′‐biphenylene‐α‐[4″‐(N,N′‐diphenylamino)diphenyl]vinylene‐alt‐5‐(2′‐ethylhexyloxy)‐2‐methoxybenzene} or poly{4,4′‐biphenylene‐α‐[4″‐(N,N′‐diphenylamino)diphenyl]vinylene‐alt‐9,9‐dihexylfluorene} as the emitting layer was 250 or 1000 cd/m², respectively. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 341–347, 2007     

在无机盐和阴离子表面活性剂存在下2-(5-溴-2-噻唑偶氮)-5-二乙氨基苯甲酸与镍显色反应的研究

本文合成了新显色剂2-(5-溴-2-噻唑偶氮)-5-二乙氨基苯甲酸(简称5-Br-TAEB),利用光度法测定了试剂的三级质子化常数,研究了它与镍显色反应的最佳条件,同时对表面活性剂及无机盐的作用机理进行了初步探讨。实验结果表明,在NaCl和NaDS存在下,pH=5.0～8.0范围内,5-Br-TAEB与镍形成稳定的蓝色络合物,络合比为Ni~(2+):5-Br-TAEB=1:2,摩尔吸光系数ε_(642)=1.23×10~5 SL·mol~(-1)·cm~(-1)。镍浓度在0～10μg/25ml范围内服从比尔定律,方法用于铝合金中镍的测定,结果满意。     

二连通偶图的周长

本文给出了二连通偶图 G 的周长的下界的新的形式及 G 为哈密尔顿的新的充分条件.     

Un modèle stochastique pour l'étude du bruit de fond dans un réacteur contrôlé par un dispositif de réglage automatique

Résumé On essaie de trouver l'équation du mouvement de la barre de contrôle d'un réacteur en théorie ponctuelle à un groupe de neutrons retardés à partir des principes stochastiques.     

Measurement of the spectral distribution of a multi-mode dye laser light by using speckle patterns

A simple method of measuring the wavelength γ₁ and the spectral line spacing Δγ of a multi-mode dye laser light by using the correlated speckle patterns produced at the far-field of a diffuser is proposed. Examples of the obtained values of γ₁ and Δγ are 6.0 × 10³ Å and 3.0 × 10¹ Å, respectively.     

Bornes quasi-inferieures et bornes superieures de la pression de ruine des coques de revolution par la methode des elements finis et par la programmation non-lineaire

This work is concerned with rigid-plastic limit analysis of shells of revolution subject to rotationally symmetric loadings. These shells, of arbitrary shape, are discretized into a series of finite elements, each being a conical shell. The von Mises condition, valid for sandwich shells, is used to compare the results obtained with existing values. After assembling the finite elements, the limit analysis program is reduced to a simple application of the non-linear programming technique where both the sequential unconstrained minimization technique (SUMT) and feasible conjugate direction (FCD) are utilized respectively for statically admissible and kinematically admissible approaches. Therefore, upper bounds and lower bounds of the collapse loads are found for some sample problems : conical, spherical, ellipsoidal, torispherical shells etc. These numerical results are illustrated and compared with existing ones described in the literature.