Preparation and characterization of lithium ion-conducting glass-ceramics in the Li1 + xCrxGe2 − x(PO4)3 system

Li₂O–Cr₂O₃–GeO₂–P₂O₅ based glasses were synthesized by a conventional melt-quenching method and successfully converted into glass-ceramics through heat treatment. Experimental results of DTA, XRD, ac impedance techniques and FESEM indicated that Li_1.4Cr_0.4Ge_1.6(PO₄)₃ glass-ceramics treated at 900 °C for 12 h in the Li_1 + xCr_xGe_2 − x(PO₄)₃ (x = 0–0.8) system exhibited the best glass stability against crystallization and the highest ambient conductivity value of 6.81 × 10⁻⁴ S/cm with an activation energy as low as 26.9 kJ/mol. In addition, the Li_1.4Cr_0.4Ge_1.6(PO₄)₃ glass-ceramics displayed good chemical stability against lithium metal at room temperature. The good thermal and chemical stability, excellent conducting property, easy preparation and low cost make it promising to be used as solid-state electrolytes for all-solid-state lithium batteries.     

高效液相色谱法测定茶叶中游离糖的含量

1引言 茶叶中的游离糖不仅是构成茶叶滋味的主要成分,给茶汤带来甜醇的味道,而且在茶叶加工过程中可发生非酶促褐变作用,生成相应的醛类和吡咯类、吡嗪类等含氮化合物,因而对于茶叶的色泽和香气的形成有重要影响.     

Porous sulfated metal oxide SO<Subscript>4</Subscript><Superscript>2−</Superscript>/Fe<Subscript>2</Subscript>O<Subscript>3</Subscript> as an anode material for Li-ion batteries with enhanced electrochemical performance

Sulfated metal oxide SO₄ ^2?/Fe₂O₃ was prepared by a novel facile sol–gel method combined with a subsequent heating treatment process. The as-synthesized products were analyzed by XRD, FTIR, and FE-SEM. Compared with the unsulfated Fe₂O₃, the agglomeration of particles has been alleviated after the incorporation of SO₄ ^2?. Interestingly, the primary particle size of the SO₄ ^2?/Fe₂O₃ (about 5 nm) is similar to its normal counterparts even after the calcination treatment. More importantly, SO₄ ^2?/Fe₂O₃ exhibits a porous architecture, which is an intriguing feature for electrode materials. When used as anode materials in Li-ion batteries, SO₄ ^2?/Fe₂O₃ delivered a higher reversible discharge capacity (992 mAh g^?1), with smaller charge transfer resistance, excellent rate performance, and better cycling stability than normal Fe₂O₃. We believed that the presence of SO₄ ^2? and porous architecture should be responsible for the enhanced electrochemical performance, which could provide more continuous and accessible conductive paths for Li⁺ and electrons.     

Enhanced voltammetric anion sensing at halogen and hydrogen bonding ferrocenyl SAMs

Halogen bonding mediated electrochemical anion sensing has very recently been established as a potent platform for the selective and sensitive detection of anions, although the principles that govern binding and subsequent signal transduction remain poorly understood. Herein we address this challenge by providing a comprehensive study of novel redox-active halogen bonding (XB) and hydrogen bonding (HB) ferrocene-isophthalamide-(iodo)triazole receptors in solution and at self-assembled monolayers (SAMs). Under diffusive conditions the sensory performance of the XB sensor was significantly superior. In molecular films the XB and HB binding motifs both display a notably enhanced, but similar, response to specific anions. Importantly, the enhanced response of these films is rationalised by a consideration of the (interfacial) dielectric microenvironment. These effects, and the resolved relationship between anion binding and signal transduction, underpin an improved fundamental understanding of anion sensing at redox-active interfaces which will benefit not just the development of more potent, real-life relevant, sensors but also new tools to study host–guest interactions at interfaces.

Surface enhancement effects in the sensing of anions at redox-active molecular films are investigated in detail and rationalised based on a consideration of the dielectric binding microenvironment.     

康普顿型谐波自由电子激光器的增益与饱和特性

本文用微扰方法计算了电子分布函数，得到了康普顿型谐波自由电子激光器小信号增益及饱和增益的公式，最后对模型及结果进行了分析与讨论。     

Engineered Binding Microenvironments in Halogen Bonding Polymers for Enhanced Anion Sensing

Mimicking Nature's polymeric protein architectures by designing hosts with binding cavities screened from bulk solvent is a promising approach to achieving anion recognition in competitive media. Accomplishing this, however, can be synthetically demanding. Herein we present a synthetically tractable approach, by directly incorporating potent supramolecular anion-receptive motifs into a polymeric scaffold, tuneable through a judicious selection of the co-monomer. A comprehensive analysis of anion recognition and sensing is demonstrated with redox-active, halogen bonding polymeric hosts. Notably, the polymeric hosts consistently outperform their monomeric analogues, with especially large halide binding enhancements of ca. 50-fold observed in aqueous-organic solvent mixtures. These binding enhancements are rationalised by the generation and presentation of low dielectric constant binding microenvironments from which there is appreciable solvent exclusion.     

A new tricyclic-alpha,beta-unsaturate ketone and a new delta-hexano lactone glycoside from Adenocaulon himalaicum

Two new compounds, a tricyclic-alpha,beta-unsaturate ketone (adenocaulone) (1) and a delta-hexanolactone glycoside (adenocaulolide) (2), along with 10 known compounds 3-12 were isolated from Adenocaulon himalaicum Edgew. Their structures were elucidated by spectroscopic methods (IR, MS, 1H, 13C and 2D NMR). In addition, the antibacterial activity of compounds 2, 3 and 4 were tested.     

Nanochemoprevention by encapsulation of (-)-epigallocatechin-3-gallate with bioactive peptides/chitosan nanoparticles for enhancement of its bioavailability

Nanochemoprevention by oral consumption was developed by the encapsulation of (-)-epigallocatechin-3-gallate (EGCG) with nanoparticles that were electrostatically assembled from bioactive caseinophosphopeptides and chitosan, which was highly biocompatible and able to enhance the bioavailability of EGCG.     

The Schwarzschild black hole’s remnant via the Bohr-Sommerfeld quantization rule

A d-dimensional Schwarzschild black hole is quantized by the action variable and the Bohr-Sommerfeld quantization rule in this paper. We find that the spectra of the horizon area and the entropy are evenly spaced. The black hole mass is also quantized and it’s spectrum spacing is proportional inversely to the mass. The ground state appears and has a constant entropy $\pi k_B$ . The ground state mass is shown to be the black hole remnant predicted by the generalized uncertainty principle and may be a candidate of dark matter.