Hydrophilic microsphere based mesoscopic-lens microscope (MMM)

By increasing the hydrophilicity of microsphere, the evaporation of liquid around the microsphere will be evidently eliminated, so that the droplet can remain stable, and it is more feasible to introduce the liquid immersed MMM system in practical utilizations that require long-time observation. Compared with the non-immersed one, the liquid immersed MMM system performs better in various aspects, and it is convenient to choose microspheres on a wider scale.     

Synthesis of poly(4‐hydroxystyrene)‐based block copolymers containing acid‐sensitive blocks by living anionic polymerization

Living anionic polymerization of an acetal protected 4‐hydroxystyrene monomer, (4‐(2‐tetrahydropyranyloxy)styrene) (OTHPSt), and the chain extension of the poly(OTHPSt) anion with a variety of monomers including styrene, 4‐tert‐butylstyrene, methacryloyl polyhedral oligomeric silsesquioxane (MAPOSS) and hexamethylcyclotrisiloxane is demonstrated. The P(OTHPSt) homopolymer has a glass transition temperature well above room temperature, which facilitates handling and purification of the protected poly(4‐hydroxystyrene) (PHS). The resulting diblock copolymers have narrow dispersities <1.05. Chemoselective mild deprotection conditions for the P(OTHPSt) block were identified to prevent simultaneous degradation of the MAPOSS or dimethylsiloxane (DMS) block, thus allowing for the first reported synthesis of P(HS‐b‐DMS) and P(HS‐b‐MAPOSS). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1458–1468     

A Novel One-Pot Synthesis of Fluorinated α,β-Unsaturated Esters

The reaction of pentafluorophenylmethylene-triphenylarsorane or p-chloro-tetrafluorophenylmethyl-enetriphenylarsorane, generated in situ from methylene-triphenylarsorane and hexafluorobenzene or chloropenta-fluorobenzene, with bromoacetates giving excellent yields of 3-pentafluorophenyl or 3-p-chloro-tetrafluoro-phenyl α, β-unsaturated esters with high steroselectivity is described.     

A Novel Approach to All-Optical Generation of Ultra-Wideband Signals

Abstract

The generation of ultra-wideband signals in the optical domain is highly desirable for ultra-wideband-over-fiber systems, which has recently become a topic of interest. In this article, a novel and simple approach to achieve all-optical generation of ultra-wideband signals is proposed, which is based on delaying and superimposing optical Gaussian pulses with opposite polarities. The proposed system is capable of generating both ultra-wideband monocycle and doublet pulses, and the polarity of the generated ultra-wideband monocycle pulses can be fast-switched to implement pulse polarity modulation with the required bit pattern. A model to describe the proposed system is developed, and the generation of ultra-wideband signals is demonstrated with simulations and a proof-of-concept experiment.     

A Novel One-Pot Synthesis of 2,4-Enynyl Amides

Silylated 2,4-enynyl amides can be synthesized by the reaction of 3-(trimethylsilyl)-2-propynylidenetriphenylarsorane, generated in situ from the corresponding arsonium salt and n-butyllithium, with α-bromoacetamides in 40–59% yields (two steps) and with high stereoselectivity.     

康普顿效应中电子-光子碰撞过程的研究

康普顿散射公式中光子波长的连续变化与光量子假说在表面上存在着不一致.为此文章分析了康普顿效应中电子和光子的碰撞过程,指出康普顿散射光子波长的连续变化可以通过自由电子连续的“虚光子吸收”和“虚光子发射”过程来加以说明.     

A versatile A2 + B3 approach to hyperbranched polyacenaphthenequinones

A series of hyperbranched polyacenaphthenequinones has been prepared by superelectrophilic aromatic substitution of (substituted) acenaphthenequinone and 1,3,5‐tris‐(4‐phenoxybenzoyl)benzene via a facile A₂ + B₃ approach. Because of the strongly increased reactivity of the second A functionality, gelation was efficiently avoided during the polymerization. The structure of the resulting polymer was characterized by NMR spectroscopy and gel permeation chromatography. Further modification of the hyperbranched polyacenaphthenequinone was explored both on the acenaphthenequinone and aromatic moieties. Moreover, the polymer modified through sulfonation was investigated as a water‐soluble acid catalyst for the degradation of biomass resources. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2596‐2603