发光分析的发展概述

光的基础知识、应用以及未来的发展趋势。文章按照不同的分类形式介绍了发光分析的发展状况及目前的使用状况,并针对当前的发展水平作出了预测。     

High-performance doped carbon electrocatalyst derived from soybean biomass and promoted by zinc chloride

A high-performance doped carbon catalyst with a BET surface area of up to 949 m² g⁻¹ has been prepared by pyrolyzing soybean biomass with ZnCl₂ as an activator, followed by acid leaching with H₂SO₄ and graphitization. For the cathodic reduction of oxygen, the catalyst exhibits excellent activity in an alkaline medium. Its onset potential and half-wave potential for the oxygen reduction reaction reach −0.02 V and −0.12 V (vs. Ag/AgCl) in 0.1 M KOH, almost comparable to those of commercial 20 wt% Pt/C catalyst. It is found that the addition of zinc chloride can significantly enhance the catalyst's surface area and activity. We suggest that the high performance of this type of catalyst is mainly contributed from its high active center density resulted from the high surface area of the catalyst, which is caused by the activation of zinc chloride.     

3次谐波电流对照明线路导体截面选择的影响

照明配电系统中,气体放电灯产生的3次谐波电流对中性线导体电流影响很大。分析了3次谐波电流在三相四线制线路中的影响,导体截面选择的依据和相关计算。实例计算分析结果表明,在照明供电线路中,3次谐波电流对导线截面的选择起决定作用,因此在照明线路的设计中应考虑谐波的影响,避免供电事故的发生。     

纤维形态特性对纸张结构和性能的影响

纤维特征在造纸过程中影响纸张的结构,决定纸张的性能。本文主要论述了造纸纤维的几种重要特征,如纤维长度、粗度,纤维强度等,分析了纤维的特征对纸张结构和性能的影响。     

建筑实训馆在砌体结构课程教学中的应用实践

针对砌体结构课程传统教学方式效果不佳的问题,尝试进行课程教学改革。结果表明,以建筑实训馆教学资源为平台,利用建筑实训馆实物开展现场教学,既能激发学生的学习兴趣,又能加深学生对知识点的理解,教学效果良好。     

Mn/Cu nanoclusters-grafted N-doped carbon nanotubes: Robust oxygen electrode catalysts for Zn-air batteries

Developing efficient nonprecious electrocatalysts that can drive the oxygen electrode reactions in zinc-air batteries (ZABs) is important but remains challenging. In this work, novel materials comprising Mn/Cu nanoclusters-grafted N-doped carbon nanotubes are synthesized by preparing and then pyrolyzing Mn/Cu polyphthalocyanine-encapsulated carbon nanotubes (CNTs), followed by treating the products with acidic solution. The materials are named CNTs@(Mn,Cu)PPc-T, where T denotes the pyrolysis temperature in °C, and they are demonstrated to serve as efficient oxygen electrode catalysts for zinc-air batteries (ZABs). Among them, the one synthesized at 900 °C, CNTs@(Mn,Cu)PPc-900, requires more positive onset and half-wave potentials for reduction of oxygen and a low overpotential for the evolution of oxygen. A rechargeable ZAB assembled with CNTs@(Mn,Cu)PPc-900 electrocatalyst delivers a high power density (158.5 mW cm⁻²) and displays an excellent stability in 200 cycles of charge/discharge (in over 33 h). Such performance is even superior to that of a ZAB containing the benchmark Pt/C + RuO₂ catalyst as an air cathode under identical testing condition.     

微萃取-聚结分离技术在碳四脱甲醇中的应用

针对某石化公司混合碳四深加工项目中因甲醇水洗塔效率的局限性而导致混合碳四中甲醇含量超标的问题,开发了一种混合微萃取耦合模块化深度聚结分离的碳四脱甲醇的成套技术设备,并在某石化公司现场进行中试侧线实验研究。实验结果表明,该成套设备在进出口压降为5kPa,注水比例为5%,停留时间180s以内：对入口甲醇含量分别为300~400μL/L,1200~1400μL/L和40000~50000μL/L的混合碳四,出口甲醇含量为10~30μL/L、50~100μL/L和4000~5000μL/L;分离效率分别为96%、95%及88%以上。分离迅速且在较宽的操作弹性范围内表现出深度分离甲醇的能力及低压降的特点,表明了该技术在碳四水洗脱甲醇系统中具有良好的适用性,为混合碳四分离甲醇提供了新思路。     

核壳无皂乳液聚合合成苯丙表面施胶剂的研究

采用核壳无皂乳液聚合技术合成了苯丙表面施胶剂,在25%的单体浓度下,通过改变稳定剂的用量、核层软硬单体配比、功能单体的用量、乙烯基磺酸钠的用量、引发剂和相对分子质量调节剂的用量获得了施胶效果的变化规律以及最佳合成条件,产品的性价比高于德国BK-532产品。     

木材造纸废弃物基质对番茄生长发育的影响

利用木材造纸废弃物（造纸除尘木屑和造纸污泥）制作蔬菜栽培基质。以造纸除尘木屑∶造纸污泥（体积比）分别为3∶1、5∶1、7∶1等3种类型的栽培基质进行番茄无土栽培的比较研究。结果表明：不同配比木材造纸废弃物栽培基质对番茄生长发育、产量的影响均有明显差别。番茄在除尘木屑和污泥基质3∶1的情况下,每667m2番茄产量达8224.6kg,较对照土壤栽培增产13.3%,是较适宜的栽培基质配方。本实验证明,木材造纸废弃物可为大棚作物无土栽培提供一种新的基质资源。     

2，4-二溴苯酚的合成实验

研究了以苯酚为原料,在乙醇一水介质中,进行溴化反应生成2,4-二溴苯酚的优化工艺条件。合成最佳反应条件为：苯酚、溴素与双氧水的物质的量比为1：0．98：0．98,演化反应温度为0—5℃;反应时间为2h;洗涤温度为40—50℃。优化条件下,收率可达96％,产品经质谱验证及气相色谱分析,百分含量为98．3％。