Molecular histology analysis by matrix‐assisted laser desorption/ionization imaging mass spectrometry using gold nanoparticles as matrix

Gold nanoparticles (AuNPs) were applied and optimized as matrix for matrix‐assisted laser desorption/ionization mass spectrometry analysis of animal tissues, and enabled histological analysis of animal tissues at molecular level by imaging mass spectrometry (IMS). AuNPs were coated on animal tissue in a solvent‐free manner via argon ion sputtering. Metabolites, including neurotransmitters, fatty acids and nucleobases, were directly detected from mouse brain tissue. Based on region‐specific chemical profiles, fine histological features of mouse brain tissue and heterogeneous regions of tumor tissue were both revealed. Copyright © 2011 John Wiley & Sons, Ltd.     

基于离子注入隔离的微缩化发光二极管阵列性能

基于F离子注入隔离技术实现一种新型微缩化发光二极管(micromicro-LED)阵列器件,并系统研究注入能量及发光孔径对micro-LED阵列器光电性能的影响.研究结果表明:相比于F离子50 ke V单次注入器件, 50/100 ke V两次注入器件具有更好的光电性能,器件反向漏电降低8.4倍,光输出功率密度提升1.3倍.同时,在不同的发光孔径(6, 8, 10μm)条件下,器件反向漏电流均为3.4×10–8 A,但正向工作电压随孔径增大而减小,分别为3.3, 3.1, 2.9 V.此外,器件不同发光孔径的有效发光面积比(实际发光面积与器件面积之比)分别为85%, 87%, 92%.与传统台面刻蚀micro-LED器件相比,离子注入隔离技术实现的micro-LED器件具有较低反的向漏电流密度、较高的光输出密度及有效发光面积比.     

Acid/Base‐Mediated Uptake and Release of Halide Anions with a Preorganized Aryl‐Triazole Foldamer

A new approach for the construction of artificial receptors capable of selectively uptake and release of halides to mimic the biological halide ions pumps is developed, in which the preorganized aryl‐triazole foldamer was designed to bear a resorcinolic group in the central strand as a switch regulator. By using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene/picric acid as the trigger, the foldamer can be switched between “w”‐shape and helical conformation. Due to the large, half‐open cavity as well as the additional electrostatic repulsion between oxyanions and guest halide, the foldamer in “w”‐shape possesses a much weaker affinity for chloride, bromide, and iodide anions than those in the helical conformation in 6:94 (v/v) [D₆]DMSO/CDCl₃. When the foldamer and chloride ions have the same initial concentrations of 1 mM , 70 % chloride ions in the solution could be reversibly bound or released upon switching.     

High-pressure x-ray diffraction station at the beijing synchrotron radiation facility

Abstract

In the second phase construction of further insertion devices, beamlines and experimental stations at the Beijing Synchrotron Radiation Facility, a dedicated high-pressure x-ray diffraction station will be constructed. We outline the synchrotron radiation source, beamline optics and high-pressure x-ray diffraction apparatus. This facility is planned to operate for users in 1994.

Presented at the IUCr Workshop on ‘Synchrotron Radiation Instrumentation for High Pressure Crystallography’, Daresbury Laboratory 20-21 July 1991     

Analysis of ginsenoside content,functional genes involved in ginsenosides biosynthesis,and activities of antioxidant enzymes in Panax quinquefolium L. adventitious roots by fungal elicitors

Research on Chemical Intermediates - In this study, Candida tropicalis, Aspergillus niger, and a mixture of their cultures were previously used as fungal elicitors in Panax quinquefolium...     

Fabrication of fluorographene nanosheets with high yield and good quality based on supercritical fluid-phase exfoliation

This article presents a novel and simple method of supercritical fluid-phase exfoliation to fabricate fluorographene (FG) nanosheets with high yield and good quality. After soaking with supercritical CO₂ and glycol at 10 MPa and 50 °C for 24 h, fluoride graphite powder was exfoliated by the intercalated CO₂ and glycol molecules during an abrupt depressurization step. Here, supercritical CO₂ acted as a penetrant and glycol acted as a “molecular wedge” to exfoliate fluoride graphite very well. The properties of FG nanosheets were detected by TEM, AFM, UV spectra, FTIR, XPS, Raman spectra, and XRD, which show the possibility of producing thickness-controlled FG nanosheets by varying numbers of supercritical CO₂ process and the high yield of pure FG nanosheets of 32 wt%, four times higher than that of the sample treated only by the traditional method of sonication. Its simplicity, high productivity, low cost, and short processing time make this technique suitable for large-scale manufacturing of FG nanosheets.     

Direct conversion of fructose-based carbohydrates to 5-ethoxymethylfurfural catalyzed by AlCl3·6H2O/BF3·（Et）2O in ethanol

Direct conversion of fructose-based carbohydrates to 5-ethoxymethylfurfural (EMF) catalyzed by Lewis acid in ethanol was investigated. It was found that BF3(Et)2O was favorable for 5-hydroxymethylfurfural (HMF) etherification to EMF. BF3(Et)2O combination with AlCl3 6H2O with the molar ratio of 1 was an effective catalyst system for synthesis of EMF from fructose-based carbohydrates. 55.0%, 45.4% and 23.9% of EMF yields were obtained from fructose, inulin and sucrose under optimized conditions, respectively.