Syntheses, characterization and fluorescent properties of two triethylene-glycol dicoumarin-3-carboxylates

Two novel triethylene-glycol dicoumarin-3-carboxylates were synthesized and characterized by element analysis, (1)H NMR, FT-IR and UV-vis absorption spectra. The photoluminescent behaviors of triethylene-glycol dibenzo[5,6]coumarin-3-carboxylate doped in PMMA were discussed. These compounds exhibit strong blue emission under ultraviolet light excitation. Compared to coumarin-3-triethylene glycol diester, the absorption and emission spectra of benzo[5,6]coumarin-3-triethylene glycol diester was bathochromically shifted due to the larger conjugation of benzene moiety. These derivatives have potential possible to explore organic electroluminescent materials.     

声学整流效应的新现象

本文描述了一种新的声学整流效应现象,当Helmholtz共振腔内部声源以共振频率激振时,整流以一股湍流喷流形式发生。流动显示、热线和激光测量结合起来对此声学整流过程进行了研究,结果表明整流是由Reynolds应力作用产生的。     

Cu(I)-promoted one-pot synthesis of 1,4-disubstituted 1,2,3-triazoles from anti-3-aryl-2,3-dibromopropanoic acids and nitrobenzaldehydes

A series of 1,4-disubstituted 1,2,3-triazoles were synthesized through a one-pot process from easily available anti-3-aryl-2,3-dibromopropanoic acids and nitrobenzaldehydes in hexamethylphosphoric triamide. Inexpensive copper(I) iodide was the catalyst.     

Real-time measurement of atmospheric parameters for the 127-element adaptive optics system of 1.8-m telescope

A real-time method for measuring atmospheric parameters based on co-processor field-programmable gate array (FPGA) and main processor digital signal processing (DSP) is proposed for ground-based telescopes with adaptive optics (AO) systems. Coherence length, outer scale, average wind speed, and coherence time are estimated according to closed-loop data on the residual slopes and the corrected voltages of AO systems. This letter introduces the principle and architecture design of the proposed method, which is successfully applied in the 127-element AO system of the 1.8-m telescope of Yunnan Astronomical Observatory. The method enables real-time atmospheric observations with the same object and path of the AO system. This method is also applicable to extended objects.     

Visual and fluorometric determination of telomerase activity by using a cationic conjugated polymer and fluorescence resonance energy transfer

Microchimica Acta - The detection of telomerase activity is important in cancer diagnosis and in screening for anti-cancer drugs. This work describes a fluorometric method for the determination of...     

新席夫碱BPDIB的分析应用研究：Ⅱ.荧光熄灭法测定水中微量铬（Ⅵ）

研究了新荧光试剂邻苯二胺缩双吡哆醛的分析应用。在稀硫酸（ｐＨ１．７－１．８）溶液中，铬（Ⅵ）能氧化邻苯二胺缩双吡哆醛，使其荧光熄灭，其熄灭程度与铬（Ⅵ）量成线性关系，据此提出了荧光熄灭测定水中微量铬（Ⅵ）的方法，铬（Ⅵ）的检出限为６．１１μｇ／Ｌ。     

A new route to fabricate large-area, compact Ag metal mesh films with ordered pores

Ordered Si nanowire (SiNW) arrays can be fabricated by metal-assisted chemical etching. The metal mesh films (MMFs) are extremely important for achieving a high quality of the SiNWs. We have developed a two-step chemical deposition method to obtain compact porous Ag MMFs. By the separation of the nucleation and growth stages of the metal in the two-step deposition processes, the overgrowth of the metals to form randomly aggregated irregular metal particles can be overcome. Hexagonally arranged polystyrene (PS) latex microspheres have been employed as a template for the deposition of porous Ag MMFs. The spacing of the pores in the Ag MMFs is determined by the diameter of PS microspheres, and the pore size can also be tuned by changing Ar plasma etching time. One of the main advantages of the two-step deposition method lies in that Ag MMFs can be produced with PS microspheres that are not limited to a single layer, which dramatically simplifies the tedious processes of producing a monolayered PS template. The two-step chemical deposition method shows great potential in metal-assisted chemical etching.     

Supercapacitor electrodes with especially high rate capability and cyclability based on a novel Pt nanosphere and cysteine-generated graphene

In the present work, supercapacitors based on graphene/Pt films show especially high rate capability (120 F g(-1) even at 50 A g(-1)) and cyclability (no attenuation over 10,000 cycles) and peculiar nanosphere morphology after electrochemical cycling. Furthermore, supercapacitors based on the graphene powder with a binder exhibit high specific capacitance (249 F g(-1) at 0.1 A g(-1)), long cycle life (no attenuation over 40,000 cycles) and high rate capability (150 F g(-1) even at 50 A g(-1)), which are much better than those of most graphene electrode materials. These indicate the great potential of the cysteine reduced graphene electrodes in energy storage.