氨水混合吸收剂脱除CO2实验研究

氨水作为一种很有应用前景的CO2化学吸收剂,存在吸收速率慢的问题.使用湿壁塔实验台,考察了不同种类的添加剂(MEA、PZ、1-MPZ、2-MPZ)对氨水吸收CO2速率的影响.结果表明,4种添加剂均能明显提高氨水吸收CO2的速率,其中PZ具有最好的促进效果.0、0.1、0.3和0.5 mol·mol-1负荷下,3 mol·L-1NH3+0.3 mol·L-1PZ溶液的总传质系数(KG)分别是3 mol·L-1NH3溶液在相应负荷下的3、3.2、3.2和2.9倍.改变反应温度、添加剂量、PZ浓度等条件对基于NH3/PZ混合吸收剂吸收CO2的反应过程进行实验,得到了其在不同条件下的KG,初步探讨CO2吸收的反应机制,并计算出准一级反应速率常数为42.7 m3·(mol·s)-1.     

接种丛枝菌根真菌对蜈蚣草吸收铀的影响

采用盆栽土壤实验,模拟铀(uranium,U)污染土壤,以蜈蚣草(Pteris vittata L.)为研究材料,每盆接种丛枝菌根真菌地表球囊霉(Glomus versiforme,Gv)30 g,探索蜈蚣草菌根对U污染土壤不同时间段的修复效果.结果表明,蜈蚣草菌根侵染率2013年9月最低为57.14%,2014年3月最高为75.20%,呈先上升后下降的年周期变化规律;同一时期蜈蚣草的生物量(干重)Gv组显著高于CK组,根系最为明显;接种Gv组蜈蚣草各器官总U含量均显著高于CK组,且被吸收的U主要固定在根部,Gv组根部总U含量均高于同一时期CK组;接种Gv组基质中总U含量小于CK组,其中接种Gv后蜈蚣草对铁锰氧化态和硫化物态U的吸收效果最好;基质中各形态U随培养时间的延长含量均呈下降趋势.接种Gv组比CK组富集系数大,且均大于1;菌根侵染率与富集系数呈显著正相关关系.以上结果说明接种Gv促进蜈蚣草对U的吸收,因此,蜈蚣草丛枝菌根真菌共生体对治理U污染土壤有良好的应用前景.     

Aluminium in tea plantations: mobility in soils and plants, and the influence of nitrogen fertilization

The levels of extractable aluminum (Al) in soils of tea plantations, Al concentrations in tea leaves and the impact of nitrogen fertilization on these two parameters were investigated. In addition, the properties of soils from tea plantations were compared to those from soils of adjacent non-tea fields to evaluate the effect of land use conversion (from non-tea soils to tea soils). Exchangeable Al (extracted in 1 mol l⁻¹ KCl) ranged from 0.03 to 7.32 cmol_c kg⁻¹ in 94 tea fields and decreased rapidly with increasing soil pH. In comparison with non-tea soils, tea soils had a significantly lower pH and exchangeable Mg²⁺ concentration but higher organic matter contents and exchangeable K⁺ concentration. Contents of extractable Al were not different (P > 0.05) between these two soils. The concentrations of Al in mature tea leaves correlated significantly with exchangeable Al in soil samples taken at a depth of 20–40 cm and with exchangeable Al saturations in soil sampled at␣depths of 0–20 and 20–40 cm. In the pot experiment, nitrogen fertilization significantly increased extractable Al levels but decreased soil pH and the levels of exchangeable base cations. Nevertheless, the levels of Al in mature leaves and young shoots were significantly reduced by the application of large amounts of N fertilizer.     

微纳米气液分散体系吸收NO

以模拟烟气为气源,去离子水为水源,通过微纳米气泡发生器形成微纳米气液分散体系,吸收模拟烟气中的NO,考察了多种因素对脱硝率(η)和气相体积总传质系数(KGa)的影响,分析了微纳米气液分散体系吸收NO的反应机理。结果表明:η和KGa随着进气NO体积分数和十二烷基苯磺酸钠(SDBS)质量浓度的提高而下降;随着吸收液初始pH的提高先降低后升高;随着进气O_2体积分数的增大而提高;随着吸收液温度的升高先提高后降低;控制进气NO体积分数为0.06%时,在吸收液初始pH为2.0、吸收剂为去离子水、吸收液温度为25℃、进气O_2体积分数为10%的最佳条件下,脱硝率可达81.0%。微纳米气液分散体系是通过产生羟基自由基从而对NO进行氧化吸收的。     

电化学间接氧化法处理H_2S气体的研究

采用填料塔对铁盐溶液吸收 H2 S的过程进行了初步研究 ,考察了气液比、填料层高度、吸收温度、Fe3+浓度、进气 H2 S浓度和 H+浓度等因素对 H2 S去除率的影响。结果表明 ,气液比、填料层高度和吸收温度对吸收效率的影响比较显著。通过正交试验选出最佳工艺条件 ,在此工艺条件下 H2 S的去除率接近 10 0 %。     

用分光光度法测定有机质的研究

在强酸性溶液中、165℃和催化剂作用的条件下,土壤中的有机碳被K2Cr2O7迅速氧化,而K2Cr2O7中的Cr6+还原成Cr3+,Cr3+在600nm波长上有特征吸收,其吸光度与有机碳的浓度成正比。根据吸光度可计算出土壤有机质的含量。实验证明试剂和工作曲线的斜率有很好的稳定性和重现性。分光光度法测定有机质快速、准确。     

分光光度法测定测田废水中的COD_(Cr)

为了快速监测油田废水中的化学需氧量ＣＯＤＣｒ,因此采用ＴＬ－１（Ａ）型污水ＣＯＤＣｒ速测仪进行加热催化消解,然后再用分光光度比色法测定ＣＯＤＣｒ,实验中进行了方法的准确度、精确度及Ｃｌ－影响实验,并与标准的重铬酸钾法进行了对比实验,结果说明分光光度法简单快速、重现性较好、准确度较高,对同一产品的测定结果与重铬酸钾法非常一致。因此,本方法可用于油田废水中的ＣＯＤＣｒ监测。     

纳氏试剂光度法测定废水中氨氮的问题讨论

应用纳氏试剂比色法测定废水中的氨氮时,水样显色后稳定时间短,影响测定结果的准确性,针对这一问题进行了实验研究。实验中对主要影响因素Ｉ－和ＯＨ－的浓度变化进行了条件实验,结果表明选用所配的Ⅲ型纳氏试剂（ＫＩ含量为７．５ｇ）,可获得稳定的有色胶体,也可采用Ⅰ型纳氏试剂（ＫＩ含量为７．０ｇ）、在中和硼酸后再多加２ｍＬＮａＯＨ（１ｍｏｌ／Ｌ）,也可获得稳定的有色胶体。     

A SIMPLE TECHNIQUE FOR ESTIMATING ABSORPTION AND SCATTERING COEFFICIENTS1

ABSTRACT: Results from five different test systems, which include a wide range of optical conditions, indicate credible estimates of the values of the absorption and scattering coefficients can be calculated from paired measurements of Secchi disc transparency and the diffuse attenuation coefficient. The diagnostic utility of the estimates in identifying components and processes that regulate light penetration is demonstrated for three different cases. The simple estimation technique is valuable in the analysis of existing data bases that lack comprehensive optical information to develop and evaluate alternate models for light penetration and to establish the experimental needs of future field programs to support lake management efforts.     

共沉淀—原子吸收法分析铁强化盐中的铁

本文采用原子吸收分光光度法,测定铁强化盐中微量铁。用数理统计方法检证了方法的可靠性。