化学氧化合成聚(苯胺-鲁米诺)复合纳米线的电化学发光特性研究

以过硫酸铵为氧化剂,通过氧化苯胺和鲁米诺混合溶液合成了聚(苯胺-鲁米诺)复合纳米线。相对于鲁米诺425 nm处的最大荧光发射波长,复合纳米线中聚鲁米诺的最大荧光发射波长明显红移到465 nm处。采用简单的滴凃方式将聚(苯胺-鲁米诺)复合纳米线修饰于石墨电极表面,形成一层稳定的聚(苯胺-鲁米诺)复合纳米线膜。此聚(苯胺-鲁米诺)纳米线膜修饰电极呈现出良好的电化学发光特性,H2O2对化学合成的聚(苯胺-鲁米诺)纳米线电化学发光呈现出增敏效应。在优化实验条件下,修饰电极的电化学发光信号与H2O2在5.0×10#9~1.0×10#5mol/L范围内呈线性关系,检出限为2×10#9mol/L。     

Preparation of TiO2/ITO film electrode by AP-MOCVD for photoelectrocatalytic application

Titanium dioxide (TiO2 ) thin films were grown onto Indium tin oxide (ITO) glass under atmospheric pressure by chemical vapor deposition (AP-MOCVD) using titanium tetraisopropoxide astitanium precursor. The as-prepared TiO2 /ITO films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and photoelectrochemical measurements. Their photocatalytic (PC) and photoelectrocatalytic (PEC) activities were evaluated based on the results of methyl orange dye (MO) degradation experiments in aqueous solution. The difference between the front side (EE, electrolyte/electrode interface) and the back side (SE, substrate/electrode interface) illumination was evaluated in both photocurrent and MO degradation experiments. The effect of the film thickness on degradation rate by PEC under the two illumination directions was also studied. Stability of TiO2 /ITO film electrode was investigated in repetitive degradation experiments. Overall, the TiO2 /ITO film with thickness ranging from 321 to1440 nm deposited by MOCVD method is an effective photoelectrode for MO degradation under SE illumination in PEC reaction system.     

Determination of chlorine in titanium sponge by inductively coupled plasma optical emission spectroscopy with microwave digestionEI北大核心CSCD

A determination method for chlorinity in titanium sponge by inductively coupled plasma optical emission spectroscopyICP-OESwas established. The sample was fully dissolved by microwave digestion at high temperature. The spectral line of 134.724 nm was chosenand the effect of coexisting impurities of SiFe MnMgCaNiCr and main matrix was investigated. The results showed that there was no obvious interference for the determination of chlorine. A good linear relationship of chlorinity was exhibited in the range of 0-10 mg/Lr≥0.999with the standard addition recoveries of 98.7%-104% and the RSDs of 2.8%. This method could detect trace chlorine in titanium sponge reliabely. © 2022, Youke Publishing Co.,Ltd. All rights reserved.     

关于Q-曲率流的几个注记

标准球面上的预定纯量曲率问题已经得到很好的研究,为此,几种不同的方法发展起来了.它的高维对应的问题即预定Q-曲率问题也吸引了众多人的注意.负梯度流的方法在处理此类问题上似乎十分有效,至少在曲率备选函数是正的情形下是如此的.本文的目的在于指出,对于指数非线性增长的预定Q-曲率问题,Q-曲率备选函数的正性假设是不必要的.     

Polycyclic aromatic hydrocarbons in the centralized wastewater treatment plant of a chemical industry zone: Removal, mass balance and source analysis

Increased attention has been given to the fate of pollutants such as polycyclic aromatic hydrocarbons (PAHs) introduced to the wastewater treatment plants.Dissolved and adsorbed PAHs were detected in the centralized wastewater treatment plant of a chemical industry zone in Zhejiang Province,China.The most abundant PAHs were the low molecular weight PAHs (e.g.,Acy,Ace,Flu and Phe),accounting for more than 80% of the total 16 PAHs in each treatment stage.Phase partitioning suggested that the removal of PAHs in every treatment stage was influenced greater by the sorption of particles or microorganisms.The removal efficiencies of individual PAHs ranged between 4% and 87% in the primary sedimentation stage,between 1% and 42% in anaerobic hydrolysis stage,between <1% and 70% in aerobic bio-process stage,between 1.5% and 80% in high-density clarifier stage,and between 44% and 97% in the whole treatment process.Mass balance calculations in primary stage showed significant losses for low molecular weight PAHs and relatively good agreements for high molecular weight PAHs as well as in anaerobic hydrolysis,high-density clarifier stage and sludge stream for most PAHs.Great gains of 60%-150% were obtained for high molecular weight PAHs in aerobic bio-process stage due to biosorption and bioaccumulation.Our investigations found that PAHs entering the wastewater treatment plant (WWTP) could be derived from the dyeing chemical processes as the byproducts,and the contribution supported by the largest dyeing chemical group was up to 48%.