军光放电降解酸性红染料废水

利用辉光放电这一高级氧化技术处理酸性红染料废水。辉光放电降解酸性红的动力学过程显示,符合一级反应动力学方程;研究了不同条件下（如电压、电极间距和pH）辉光放电降解酸性红的降解效率,得出实验室内辉光放电降解酸性红的最佳试验条件：酸性条件pH3、电压600V和电极间距10mm。在此条件下,辉光放电降解酸性红染料废水具有降解率高、时间短和效果好等优点。     

高压脉冲放电降解直接耐晒翠蓝GL废水

采用自制高压脉冲放电等离子体反应器降解染料废水中的DB86(直接耐晒翠蓝GL),研究脉冲电压、电极间距、气体流量、初始质量浓度等参数对DB86降解效果的影响，并分析放电过程中质量浓度ρ_TOC、pH值的变化规律。结果表明：DB86质量浓度为100 mg/L时，在脉冲电压22 kV、脉冲频率50 Hz、放电间距8 mm、空气流量3.0 L/min、电导率200μS/cm条件下降解效果达到最好。动力学研究表明，高压脉冲放电降解DB86染料废水的过程符合伪一级反应动力学模型。通过对DB86分子降解机理分析，得出放电过程产生的活性物质导致染料废水降解，其中·OH起关键作用。并生成第3方酸性物质甲酸、乙酸等。整个放电过程中溶液的pH值呈下降趋势，溶液最终显酸性。     

双通道放电等离子体处理模拟酸性紫红染料废水

采用低温等离子体技术,在自行设计的双通道放电等离子体装置中,对模拟酸性紫红染料废水进行了降解研究.考察了电极距液面间距、液层厚度、初始浓度、pH等因素对酸性紫红废水脱色率的影响.结果显示,电极距液面间距越小,废水脱色率越高;随着液层厚度的增大,相同时间下脱色率降低;随着初始浓度的增大,在相同放电时间下脱色率降低,随着时间的延长,不同浓度的染料废水脱色率都可达到90%以上;pH对脱色率的影响不大.结论表明自行设计的双通道放电等离子体装置对模拟酸性紫红染料废水的脱色率高,同时具有处理时间短,对废水的操作条件较宽,不受pH的限制等优势.     

辉光放电等离子体降解番红花红T染料废水

利用辉光放电等离子体(GDP)对阳离子染料番红花红T模拟废水进行降解。通过测量番红花红T染料废水处理前后在紫外可见区最大吸收波长554 nm的吸光度来计算降解效率,同时考察在降解过程中溶液的pH、电导率的变化。结果表明,初始质量浓度分别为50、100 mg/L的番红花红T水溶液在经过15 min后降解效率分别高达99.34%、98.99%,且降解过程符合准1级动力学特征。随着放电处理的进行,溶液的电导率增大、pH降低,说明在放电处理进行中产生了大量荷电离子及酸性物质。通过对3种不同情况下降解结果的比较(放电处理加Fe离子、仅放电处理和放电处理加Na2SO4),推测对番红花红T起主要降解作用的是羟基(·OH)自由基。     

双通道放电等离子体对酸性嫩黄的脱色规律及机理研究

以偶氮染料酸性嫩黄水溶液为例,采用低温等离子体技术,在自行设计的双通道放电等离子体装置中考察双通道放电低温等离子体降解染料废水的影响因素及反应机理.结果表明,相同放电时间下随电极距液面间距减少,废水脱色率增高;随着液层厚度的增大,初始质量浓度的增大,在相同放电时间下脱色率会降低,但随着时间的延长,脱色率都可达到90%以上;pH对脱色率的影响不大.研究表明自行设计的双通道放电等离子体装置对模拟酸性嫩黄染料废水的脱色率高,同时具有处理时间短、对废水的操作条件较宽、不受pH限制等优势.此外进一步验证了等离子体技术对染料废水脱色的主要因素是羟基自由基.     

介质阻挡放电等离子体处理酸性大红GR废水

采用一种以待处理废水为接地极的介质阻挡放电反应器,对模拟酸性大红GR废水进行降解试验,考察了峰值电压、放电频率、放电间距、作用时间及溶液初始浓度等因素对酸性大红GR降解效果的影响,并对降解机理进行了初步探讨。试验结果表明,在废水初始质量浓度为30 mg/L,pH=2,放电间距6 mm,放电电压8 kV,放电频率10 kHz的条件下,放电处理20 min后脱色率达到76.4%;向反应体系中加入Fe2+有利于提高染料废水的脱色效果,溶液中Fe2+浓度为0.48 mmol/L时,放电处理20 min后脱色率达到92.1%。废水脱色率随处理时间的延长而提高,COD的变化则呈现上升-下降-上升-下降的趋势。酸性大红GR废水经放电处理后的中间产物主要为甲酸、乙酸、苯、对苯二酚、1-萘醌、6-萘酚、邻苯二甲酸(酐)、对羟基苯甲酸等,表明酸性大红GR分子上的C-N键断裂后,苯环在.OH的攻击下开环。降解产物中存在少量的羟基苯胺和对硝基苯胺,表明有少部分酸性大红GR的降解是通过N=N的断裂开始的。     

BiFeO3/H2O2体系有效降解酸性复红染料废水的研究

以BiFeO3和H2O2组成非均相类Fenton体系催化降解酸性复红(acidic fuchsin)染料废水.探讨了过氧化氢用量、反应时间、反应温度、催化剂用量、染料初始浓度以及pH值等因素的影响.实验结果显示在过氧化氢体积百分数为0.65％、反应时间为50 min、反应温度为303 K、催化剂用量为0.45 g/L、酸性复红溶液初始浓度为120 mg/L和pH值为7.5的最优条件下,废水脱色率＞99％.降解过程动力学的初步研究说明该过程符合一级动力学方程,在303 K时表观速率常数和表观活化能分别为0.1011 min-1、23.04 kJ/mol.     

辉光放电电解等离子体处理次甲基蓝废水

利用辉光放电电解等离子体技术对次甲基蓝废水的降解进行了研究,详细考察了电压、染料浓度、pH值、催化剂对次甲基蓝降解效果的影响。实验发现,次甲基蓝废水的优化降解条件为:工作电压610 V,pH值3.0,Fe2+催化作用下降解效率明显提高。利用紫外-可见吸收光谱监测了次甲基蓝的降解过程,结果表明,次甲基蓝先被降解成小分子,小分子继而被进一步降解。     

钛基二氧化铅阳极、泡沫镍阴极电化学降解偶氮类染料酸性红18的研究

以钛基二氧化铅作阳极,泡沫镍作阴极对偶氮类染料酸性红18溶液进行电解。在不添加隔膜的条件下,考察了电压、电流、电解质含量、pH值等因素对酸性红18电化学降解的影响,同时对不同降解时间后AR18的相对残余浓度与时间的相关性进行分析,结果表明,酸性红18的降解符合准1级反应动力学方程。在添加隔膜的条件下,对酸性红18在硫酸...     

高压放电降解甲基红废水工艺的研究

采用高压放电降解甲基红模拟废水,以降解率为考察指标,在单因素试验基础上采用响应曲面法研究甲基红废水的初始质量浓度、高压放电电压、曝入空气流量和放电时间对甲基红废水降解率的影响.得到甲基红降解最优工艺条件为:甲基红初始质量浓度46 mg· L-1,放电电压20 kV,曝入空气流量300 mL· min-1,放电时间为120 min,此时甲基红的降解率为93.6％.通过回归方程求解和响应曲面分析,得到二次多项式提取回归模型,经验证试验值与模型预测值拟合性良好.     

COMPARISON OF METHODS OF ANALYSIS OF GYPSUM1

The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO₃ and determination of CaO by KMnO₄ titration, the SO₃ by Andrews method of titration of BaCrO₄ has been found to give very reliable results with the least consumption of time.     

氢气纯度分析方法准确性的探讨

ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l／3为氧气,2／3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中：A一混…     

茶多酚提取方法进展

本文综述了国内外现有茶多酚提取方法的现状以及近期的研究进展，并对其优缺点进行了评价。这将有助于中低档茶的综合利用和茶多酚的进一步开发应用。     

HEASUREHENT OF INSTANTANEOUS RATES OF LOSS OF VOIATILE COMPOUNDS DURING DRYING OF DROPS

A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.

Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology.     

SEDIMENTATION OF BINARY MIXTURES OF PARTICLES OF UNEQUAL DENSITIES AND OF DIFFERENT SIZES

A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases.     

ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES

Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log₁₀ viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log₁₀ viscosity as a function of soda content are smooth up to 50% Na₂O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO₂, 2Na₂O) due to Molecular Substitution of CaO, MgO and Al₂O₃ for Na₂O The effect is clearly brought out by plotting (from the results of English) the change of log₁₀η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature T_a. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log₁₀η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A1₂O₃) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al₂O₃) per 100°. At the aggregation temperature the change of log₁₀η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al₂O₃. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log₁₀η due to substitution of an oxide for Na₂O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na₂O-CaO-SiO₂. Change of Viscosity of Glass (4SiO₂, 2Na₂O) due to of Substitution of B₂O₃ for SiO₂ The change of log₁₀η (from the results of English) is plotted as a function of temperature, and also the change of log₁₀η per per cent B₂O₃. The curves are more complex than for the substitution for Na₂O.     

环氧树脂羟基值测定方法的研究

利用乙酸酐、吡啶和浓硫酸混合的乙酰化试剂测定环氧树脂中羟基值含量的方法具有操作简便、滴定终点明显和分析结果误差小等优点。     

骑式摩托车油箱喷涂工艺的改进

面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。     

用两个形状指数表征粉煤灰颗粒形貌的研究

引用两个形状指数表征颗粒形状的概念,即先将颗粒形状近似为椭圆,再将椭圆图像分离:以圆为基准的颗粒宏观形状指数δ;以光滑椭圆为基准的颗粒轮廓凹凸度,即微观形状指数ζ。分析和发展了近似椭圆模型。并运用图像分析仪对粉煤灰、水泥样品进行实验。结果表明,粉煤灰颗粒的两个形状指数δ和ζ都大于水泥颗粒。证明粉煤灰颗粒的球形度、表面光滑度优于水泥,而且,随着粒径增大,δ和ζ呈下降趋势,表明磨制颗粒越粗。(?)粒形状越不规则。文中还运用近似椭圆模型再现了颗粒的模拟图像。     

典型煤碳燃烧特性研究和数值模拟

本文以三种典型煤的碳燃烧为研究对象，分别采用简单一维沉降燃烧方式和等温加热燃烧方式，实验研究了煤在快速加热条件下，其碳的初期和中，后期燃烧过程。以实验为基础，建立了煤的碳燃烧模型，变工况数值模拟了煤的碳燃烧过程，揭示了煤不同条件下的单颗粒碳燃烧特性。