Picomole‐level Formaldehyde Determination in Gaseous and Beer Samples Using Flow Injection Chemiluminescence Analysis

Based on the linear enhancement of formaldehyde (FA) within 7.0 ～ 1000 pmol l^?1 on luminol—bovine serum albumin (BSA) chemiluminescence (CL) system, FA determination in air and beer samples using CL with flow injection (FI) was proposed. The detection limit was 2.5 pmol l^?1 (3σ) and the relative standard deviations were less than 4.5% (n = 7). At a flow rate of 2.0 mL min^?1, a whole analysis from sampling to washing only needed 32 s, offering a sample throughput of 112 h^?1. This proposed method was successfully utilized to determine FA vapor pressure in liquid (121.8 ± 3.8 Pa), FA content in real air sample (8.93 ± 0.03 mg m^?3), and FA levels in beer (199.5 ± 5.6 ～ 225.2 ± 3.5 mg l^?1), giving determination recoveries from 90.7% to 109.3%. The mechanism of BSA—FA interaction was also investigated, showing FA binding to BSA was a spontaneous process mainly through hydrogen bonding and van der Waals force by FI‐CL, with binding constant K of 1.89 × 10⁶ l mol^?1 and the number of binding sites n of 0.86. Molecular docking analysis further revealed FA could enter into the pocket at subdomain IIA of BSA, with K of 1.71 × 10⁵ l mol^?1 and ΔG of ‐29.68 kJ mol^?1.     

Inactivation of Bacillus subtilis Spores Using Various Combinations of Ultraviolet Treatment with Addition of Hydrogen Peroxide

This study aims at comparing the inactivation of Bacillus subtilis spores by various combinations of UV treatment and hydrogen peroxide (H₂O₂) addition. The combinations included sequential (UV–H₂O₂, H₂O₂–UV) and simultaneous (UV/H₂O₂) processes. Results showed that B. subtilis spores achieved a certain inactivation effect through UV treatment. However, hardly any inactivation effect by H₂O₂ alone was observed. H₂O₂ had a significant synergetic effect when combined with UV treatment, while high irradiance and H₂O₂ concentration both favored the reaction. When treated with 0.60 mm H₂O₂ and 113.0 μW/cm² UV irradiance for 6 min, the simultaneous UV/H₂O₂ treatment showed significantly improved disinfection effect (4.13 log) compared to that of UV–H₂O₂ (3.03 log) and H₂O₂–UV (2.88 log). The relationship between the inactivation effect and the exposure time followed a typical pseudo‐first‐order kinetics model. The pseudo‐first‐order rate constants were 0.478, 0.447 and 0.634 min^?1, for the UV‐H₂O₂, H₂O₂–UV and UV/H₂O₂ processes, respectively, further confirming the optimal disinfection effect of the UV/H₂O₂ process. The disinfection could be ascribed to the OH radicals, as verified by the level of para‐chlorobenzoic acid (pCBA).     

Thermoelectric Properties of Sn-S Bulk Materials Prepared by Mechanical Alloying and Spark Plasma Sintering

To study the possibility of SnS as an earth-abundant and environmentally friendly thermoelectric material, the electrical and thermal transport properties of bulk materials prepared by combining mechanical alloying and spark plasma sintering were investigated. It was revealed that SnS has potential as a good thermoelectric material, benefiting from its intrinsically low thermal conductivity below 1.0 W/m/K above 400 K and its high Seebeck coefficient over 500 μV/K. Although the highest ZT value was 0.16 at 823 K in the pristine sample, further enhancement can be expected through chemical doping to increase the electrical conductivity. It was also revealed that changing the stoichiometric ratio and sintering temperature had less apparent influence on the microstructure and thermoelectric properties of SnS because redundant S in the powders decomposed during the sintering process.     

电涡流式钞票厚度检测传感器设计

在ATM机和纸币清分机中,钞票的厚度检测是必须的功能,通过钞票的厚度特征可以识别钞票上粘贴的胶带和折角等,从而剔除不合格钞票。本文论述了一种电涡流式钞票厚度检测传感器,采用并列的结构相同的多路厚度传感器,通过每路独立的厚度传感器检测出来的信号,拼接成整张钞票的厚度特征,从而识别钞票是否有异常。本传感器具有电路简单、成本低、检测范围大等优点。     

基于安卓电视机芯智能升级的应用研究

对比了目前几种安卓电视智能升级方案,提出了一种在现有电视技术条件下,通过一个自定义接口完成安卓电视机芯智能升级的方案。该方法具有电视整机机芯升级简单、便捷、成本低、原有整机利用率高的优点。并以50个管脚的自定义接口为例,具体阐述了安卓电视机芯升级的软件、硬件解决方案。     

Joint channel assignment and routing in multiradio multichannel wireless mesh networks with directional antennas

The aggregate capacity of a wireless mesh network (WMN) is severely affected by interflow interference. In this paper, we propose a network architecture that incorporates directional antennas with multiple orthogonal channels to effectively enhance the performance of WMNs. First, a sectored connectivity graph is introduced to model multiradio multichannel WMNs with directional antennas. Next we formulate the topology design, directional interface assignment, channel allocation, and routing mathematically as a mixed integer linear programming problem. This problem is solved using an iterated local search algorithm to obtain optimized network resource allocation. Simulation results indicate that the proposed architecture can achieve higher packet delivery ratio while providing better network fairness. Copyright © 2014 John Wiley & Sons, Ltd.     

Generalized intuitionistic fuzzy geometric aggregation operators and their application to multi-criteria decision making

In this paper, we extend the generalized weighted geometric and generalized ordered weighted geometric operators to intuitionistic fuzzy environments, that is, we develop a series of generalized intuitionistic fuzzy geometric operators to aggregate input arguments that are expressed by intuitionistic fuzzy values based on Archimedean t-conorm and t-norm. Then some desired properties of these aggregation operators are investigated. The relations between these operators and some existing intuitionistic fuzzy geometric aggregation operators are discussed in detail. Furthermore, applying these proposed operators, we develop an approach for multi-criteria decision making with intuitionistic fuzzy information. Finally, a practical example is given to verify the developed approach and to demonstrate its practicality and effectiveness.     

一种用于角度传感器中的仪表放大器

主要设计了一种用于角度传感器系统中的仪表放大器。为了满足角度传感器系统中对信号频率的要求,需要仪表放大器的带宽足够宽能够达到3.3 MHz。该电路采用标准三运算放大器结构电路,以折叠共源共栅结构的放大器为基础,对共模信号进行抑制,对差分信号进行放大,提高了放大器的精度,增大了仪表放大器的带宽。采用Chartered 0.35μm CMOS双栅工艺对电路进行仿真和流片验证,测试结果表明:在0.8～2.85 V内,仪表放大器的共模抑制比达到了102 dB,带宽能够达到3.3 MHz,输出摆幅为1.7 V,电路功能良好,达到了设计要求,该电路可用于汽车电子以及医疗设备系统。     

A ligand-free copper(I) oxide catalyzed strategy for the N-arylation of azoles in water

A simple and practical protocol has been developed for the cross-coupling of azoles and aryl iodides under ligand-free copper(I) oxide catalyzed conditions in water. The protocol uses tetrabutylammonium bromide (TBAB) as the phase-transfer catalyst, and water as the solvent, and shows good tolerance towards various functional groups.