Alkylated and silylated β-cyclodextrin for gas chromatographic chiral stationary phases

1　ＩＮＴＲＯＤＵＣＴＩＯＮＷｉｔｈｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｌｉｆｅｓｃｉｅｎｃｅ ,ｓｅｐａｒａ ｔｉｏｎｏｆｅｎａｎｔｉｏｍｅｒｓｆｏｒｂｏｔｈａｎａｌｙｔｉｃａｌａｎｄｐｒｅｐａｒａ ｔｉｖｅｐｕｒｐｏｓｅｓｉｓａｎａｔｔｒａｃｔｉｖｅｔｏｐｉｃ     

7H-pyrazolo[5, 1-a]benz[d,e]isoquinolin-7-ones: Yellow to orange dyes for synthetic-polymer fibres

N-Amino-1,8-naphthalimides were condensed with ketones containing an α-methylene group and the resulting hydrazones ring closed to afford derivatives of 7H-pyrazolo(5,1-a)benz(d,e)isoquinolin-7-one. These compounds coloured synthetic-polymer fibres, particularly polyester, in brilliant fluorescent greenish-yellow to orange hues of good fastness to light and sublimation. The colour of the dyes is discussed with respect to substituent effects in the pyrazole and naphthalene rings, and in relation to analogous 7H-benzimidazo(2,1-a)benz(d,e)isoquinolin-7-ones.     

Synthesis and characterization of ion conducting cellulose esters with PEO side chains

Cellulose esters with poly(oxyethylene) (PEO) side chains, denoted COE-1 and HPCOE-1A, were prepared through the homogeneous reactions between cellulose or hydroxypropylcellulose and a PEO monocarboxylic acid in the presence of N,N′-dicyclohexylcarbodiimide and 4-N,N′-dimethylamino-pyridine. The LiCF₃SO₃ complexes of the two polymers were prepared, and the effects of salt concentration on the liquid crystallinity, ionic conductivity and morphology were investigated. It has been found that the two kinds of complexes are both thermotropic liquid crystalline materials and exhibit clearing temperatures, T_c, that increase with increasing salt concentration. The increase in T_c for each system is compensated approximately by a rise in T_g, leaving the liquid crystalline temperature ranges fairly constant. A non-Arrhenius temperature dependence of ionic conductivity is predominant in both systems with the maximum conductivities occurring at [Li]/[O]≈0.07. The environmental scanning electron microscopy reveals a very rough, array-like internal structure for the COE-1 complex at this salt concentration.     

Influence of different dopants on the adsorption,morphology, and properties of self‐assembled films of poly(o‐ethoxyaniline)

Self‐assembled films of poly(o‐ethoxyaniline)—POEA alternated with sulfonated lignin (SL)—were successfully produced, and their kinetics of formation and growth investigated for different dopants (hydrochloric acid, methanesulfonic acid, p‐toluenesulfonic acid, and camphorsulfonic acid). These films were characterized by ultraviolet‐visible spectroscopy, atomic force microscopy, surface potential, and electrical resistance measurements. It has been observed that the bulkiest dopants led to a greater time for the polymer deposition and greater amount of material adsorbed. This can be explained by the lower mobility and lower solvation of the bulkiest dopant counterions, which led to a higher screening effect of the charges present in the POEA chains and therefore to a more compact molecular conformation. The morphology of the POEA films were also greatly affected by the type of dopant used, being rougher for the bulkiest dopants. The POEA films also exhibited different electrical responses upon ethylene exposure depending on the dopant, indicating a promising use for gas sensor applications. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1309–1316, 2002     

Electrochemical reduction of some 5-substituted-4-thiohydantoins at the dme

The polarographic behaviour of a series of 5-arylidene-4-thiohydantoin derivatives is reported and discussed. The reduction proceeds via a CECE mechanism in acid media with the formation of a 5-benzyl-4-thiohydantoin and other products. The mechanism is confirmed through pK_a determinations and Hammett's σ-E_1/2 relations.     

Phosphate diesters for dermatological use

A new formulation for dermatological use and hair care was studied. Phosphate diesters of the nonyl-phenol type in association with cocoimidazoline derivatives are compared with four commercial formulations. Foaming capacity, eye and skin irritation, keratin solubilization and defatting properties were studied. The mixture was the best foamforming formulation and the best defatting agent. Also, it was non-irritant for skin and eyes at adequate dilutions and did not dissolve keratin. It is a good formulation for dermatological use and hair care, due to its detergent properties. It ranks high among safe products.
Di-ésters phosphates à usage dermatologique     

Color-Stable Two-Dimensional Tin-Based Perovskite Light-Emitting Diodes: Passivation Effects of Diphenylphosphine Oxide Derivatives

The performance of tin (Sn)-based perovskite light-emitting diodes (PeLEDs) lags behind their lead analogs due to the challenges of Sn²⁺ oxidation, defect passivation, and fast crystallization. Herein, the passivation effects of diphenylphosphine oxide (DPPO) derivatives on the fabrication of PEA₂SnI₄ films are investigated. The DPPO derivatives with hydroxyl group, or including substituent group with the potential to form hydroxyl group, are unfavorable passivators due to their positive effects in accelerating Sn²⁺ oxidation. In comparison, amino-functionalized DPPO molecule is an effective additive to enhance the photoluminescence of PEA₂SnI₄ films due to the effective defect passivation as well as crystallinity improvement. Based on the optimized films, color-stable pure-red PeLEDs are demonstrated with a full width at half maximum of 23 nm at 630 nm, a maximum luminance of 451 cd m⁻², a maximum external quantum efficiency of 3.51%, and a half-lifetime of 13.7 min at 102 cd m⁻². This work opens new prospects on the selection of effective molecular additives for Sn-based perovskites.     

含硫苯衍生物对发光细菌生物毒性的QSAR研究

应用分子力学,半经验量子化学RM1方法,对29个含硫苯衍生物的几何构型进行全优化,将一系列的量子化学参数用于其结构和对发光细菌生物毒性的QSAR研究中．利用SPSS13．0软件,用多元逐步回归法建立了含硫苯衍生物对发光细菌毒性与量化参数的多元回归方程,结果表明,前线轨道能量差△E,辛醇／水分配系数（lgKow）,取代基的Hammett电荷效应常数∑σ,碳原子C（6）上的静电荷E（6）及苯环上碳原子的静电之和∑,E对其生物毒性有明显的影响,其生物毒性可用下列模型来定量描述：lg（1／EC50）=10．238—0．009△E＋3．034E（6）＋2．108∑E-0．2921gKow＋0．522∑σ,N=29,R=0．930．     

Monte Carlo acceleration method for pricing variance derivatives under stochastic volatility models with jump diffusion

Monte Carlo acceleration method for pricing variance derivatives under stochastic volatility models with jump diffusion is researched in the paper. Control variate and importance sampling techniques are used to reduce the variance of the simulated price of the derivative. Based on the closed-form solution of a simplified model with piecewise deterministic volatility and jump diffusion, control variate technique is proposed to reduce the simulation errors. Then importance sampling method is also introduced to solve the rare event of the jump part in the model. Through the analysis of the first and second moments of the underlying processes and simplified processes, the method to construct the efficient control variate is proposed. Importance sampling method enhances the effects of the control variate technique. The numerical experiments illustrate the high efficiency of the acceleration method, in accordance with the theoretical analysis. The methods in the paper can also be extended to the pricing of other path-dependent derivatives.