分光光度法测定水中活性氯的方法研究与改进

研究了N,N-二乙基-1,4-苯二胺分光光度法和便携式光度计测定水中活性氯的精密度和准确度,结果表明:便携光度测定法同实验室测定方法具有等效的准确度和精密度。对N,N-二乙基-1,4-苯二胺分光光度法研究结果表明,显色剂于4℃下保存应不超过7d;对于标准曲线测定时碘酸钾的反应时间,应由1min更改为30min。     

N,N-二乙基-1,4-苯二胺分光光度法测定水中游离氯方法的优化

按照国标方法《水质游离氯和总氯的测定N,N-二乙基-1,4-苯二胺分光光度法》HJ586-2010绘制游离氯标准曲线时存在曲线的相关系数经常0.999,无法达到国标要求(标准曲线回归方程相关系数应0.999)的问题。通过研究化学反应过程中的影响因素并优化实验条件,使标准曲线的相关系数达到了国标要求,准确性也符合方法要求。     

室内空气中氨的测定方法改进

氨在室内空气中是主要的污染物之一[1-4],氨的测定方法较多,其中靛酚蓝分光光度法(GB/T18204.25 2000)录敏度高,选择性好,但操作较复杂,为此对操作步骤中的温度和显色时间进行了改进.     

CTAB苯芴酮光度法测定工业废水中锑

目前环境监测中锑的分析,多采用2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(简称5-Br-PADAP)分光光度法、原子吸收光度法、阳极溶出伏安法测定.本法选择了十六烷基三甲基溴化铵(简称CTAB)为表面活性剂,利用苯芴酮显色分析工业废水中锑的含量.提出了显色酸度的基本条件,考察了锡、钒、铁、铬等干扰元素的消除方法.摩尔吸光系数.ε_(510)=3.3×10~4,锑量在0—50μg/25ml内符合比尔定律.     

双波长分光光度法测定含硝酸盐水样中二甲基乙酰胺

紫外分光光度法是目前水中N,N-二甲基乙酰胺(DMAC)的常用分析方法。研究结果表明,硝酸盐对紫外分光光度法测定DMAC具有很强的干扰。本研究中提出一种双波长法用于消除水中硝酸盐的干扰作用,所采用的波长对为194.0nm和219.0nm。精密度实验及加标回收实验表明,方法的相对标准偏差在4%以内,回收率为95%~102%,可有效消除硝酸盐的干扰作用。     

高灵敏显色反应体系分光光度法测定痕量镉

利用镉(Ⅱ)-碘化钾-丁基罗丹明B-PVA高灵敏显色体系分光光度法测定了水样及发样中的痕量镉,含量在0～1.5(μg/25ml)范围内符合比耳定律。表观摩尔吸光系数为1.14×10~6L·mol~(-1)·Cm~(-1)。     

分光光度法测定水中硝基苯类化合物检出限的优化

对测定水中硝基苯类化合物的锌还原-盐酸萘乙二胺分光光度法进行优化,简化了操作步骤,并将参加显色反应的水样体积由4.0 mL增加至8.0 mL,比色皿厚度由10 mm增加至20 mm,方法推荐检出限由0.20 mg/L降至0.05 mg/L,实验室检出限为0.042 mg/L,改进后的方法对标准样品的测定结果符合要求。     

二氨基联苯胺分光光度法测定水质中硒的方法改进

采用3.3＇-二氨基联苯胺分光光度法对测定水质中硒的方法进行改进，主要研究了样品中硒的测定条件，通过对不同显色波长、酸碱度显色条件、显色剂用量、酸碱度比色条件的研究，得出比较理想的定量分析条件。采用该方法测定硒，显色稳定，准确度、精密度均能达到要求。     

环境水中微量亚硝酸盐的快速测定

NO_2~-是水体监测的必测项目之一,其分析方法国内外普遍采用N-1萘—乙二胺二盐酸盐(NEDD)分光光度法.该法灵敏度高,采用先加磺胺溶液后加NEDD溶液两步显色的程序.但NEDD溶液仅能稳定1个月,而且有毒性,要避免与皮肤接触或吸入体内.此外,方法的水样用量较大,不适合样品量少的     

影响磷矿废渣中氰化物测定的干扰去除

若按常规的测定程序 ,即先用乙酸锌、酒石酸溶液蒸馏 ,然后取蒸馏液用硝酸银滴定或用异烟酸 -吡唑啉酮显色后分光光度法测定。但实验表明 ,馏出液在硝酸银滴定或异烟酸 -吡唑啉酮显色过程中都会出现黑色沉淀 ,使测定工作无法继续。通过推测 ,黑色沉淀可能是由于存在硫离子 ( S2 +)引起的。为去除其对滴定和显色过程的干扰 ,可在馏出液中加入适量碳酸镉 ( Cd CO3)或碳酸铅 ( Pb-CO3)粉末使硫离子 ( S2 +)形成沉淀 ,然后过滤除去硫离子 ,过滤液再用磷酸、EDTA蒸馏 ,馏出液再按硝酸银滴定法或异烟酸 -吡唑啉酮用分光光度法即可测定。影响…     

基于Sentinel-3 OLCI影像的渤海FUI水色指数遥感提取及应用

水色是水体水文学特征的基本要素之一。水色测定主要是采用福莱尔比色表(Forel-Ule Scale)将自然水体按颜色从深蓝到红棕共分为21个级别,用以观测、记录海洋和内陆水体的颜色。基于2020—2021年大辽河口、黄河口西南及秦皇岛近岸海域的现场实测数据和同步Sentinel-3 OLCI影像,验证了FUI水色指数遥感提取结果的准确性,发现当现场测量时间与卫星过境时间接近时,FUI水色指数遥感提取结果与实测结果基本一致。利用2021年1—12月Sentinel-3 OLCI影像,提取了渤海月均FUI水色指数遥感产品,发现渤海FUI水色指数的主要变化区间为5~17,整体呈现辽东湾、渤海湾及莱州湾沿岸海域高,秦皇岛海域及其他离岸海域低的空间分布特征,且存在秋冬季高、春夏季低的时间变化规律。此外,FUI水色指数对诸多海洋生态环境问题具有显著的指示功能。尝试将其应用于海洋水色异常和海水水质类别观测,均取得了较好的应用效果。由此可见,FUI水色指数遥感提取将在今后的海洋生态环境监测与评价方面发挥重要作用。     

近岸海域水色异常遥感监测方法研究

水体颜色是判断水体质量的重要依据，利用遥感技术检测水色异常是进行水质评估和水体污染监测的重要技术手法。基于盐城市废黄河入海口处的GF1-WFV影像数据，利用遥感影像自身光谱特征来构建水色异常判断函数，对研究区域的水色异常进行快速提取和定位，并比较分析了基于单景影像特征和多景影像特征设置判断阈值的提取结果。研究结果表明：该方法完全基于遥感影像光谱特征，可有效提取出未知类型的水色异常信息；与基于单景影像设置的判断阈值相比，基于双景影像设置的判断阈值更合理、更适用，提取速度更快，提取范围更精确，Kappa系数为0.80;另外，采用合适窗口大小进行均值滤波处理能有效防止提取结果细碎和斑块化。     

Assessing the visual impact of physical features of tall buildings: Height,top, color

Considering their features, tall building are of high importance in the view of a city. Among their important features are height, top and color which are also some of the most important factors in their effectiveness. In the present study we assessed the effectiveness of these physical features in the overall visual impact of these tall buildings and determined the significance of each of these features in the visual impact of the tall buildings. To this end, we examined a tall building in the largest city of Iran (Tehran). We altered the physical features (its height, top, and color) of the building, providing nine images for each variable element. Combining these pictures, 27 trio pictures were eventually prepared and assessed by a sample of 384 people randomly selected from the population of Tehran. Then, the data were analyzed. The results indicated that height was the most effective factor in the eyes of the citizens, followed by top and, then, color with the least effect among the three factors. In a more thorough analysis of the interactive effect of the factors on each other, we reached the conclusion that height can affect the visual impact of top and color but top can only affect the visual impact of color and slightly the impact of height. However, the effect of color on the other two factors was insignificant.     

Measurements of Wastewater True Color by 4/6 Wavelength Methods and Artificial Neural Network

The ADMI (American Dye Manufactures’ Institute) 3 and 31 wavelength (WL) methods are the most popular measurements of the wastewater true color. However, significantly different measured results were found between the ADMI 3 and 31 WL methods for the same sample. This finding indicates that the ADMI 3 and 31 WL values should not be directly substituted for each other, resulting in the incomparability of these two color values. An innovative calculation using the Back-Propagation Neural Network (BPN) was therefore proposed to replace the original calculation method proposed in Standard Method. The BPN-calculated ADMI 3 WL values were found to be very close to the corresponding measured ADMI 31 WL values. Additionally, for more accurate measurement of the true color, new measurement methods containing 4 and 6 wavelengths were proposed and cooperated with the BPN calculation model. The new approaches performed very accuracy measured results of the wastewater true color. Finally, the trained BPN calculation models were built to be applied to measure the true color of real textile samples and also performed very good measured results.     

水质 色度测定——稀释倍数法探讨

稀释倍数法是测定污水色度的国家标准方法,通过对稀释次数、稀释方法的比较实验等对色度的测定方法进行探讨,提出几点体会,在色度的测定中有一定的实用性。     

Texture Analysis for Mapping Tamarix parviflora Using Aerial Photographs along the Cache Creek, California

Natural color photographs were used to detect the coverage of saltcedar, Tamarix parviflora, along a 40 km portion of Cache Creek near Woodland, California. Historical aerial photographs from 2001 were retrospectively evaluated and compared with actual ground-based information to assess accuracy of the assessment process. The color aerial photos were sequentially digitized, georeferenced, classified using color and texture methods, and mosaiced into maps for field use. Eight types of ground cover (Tamarix, agricultural crops, roads, rocks, water bodies, evergreen trees, non-evergreen trees and shrubs (excluding Tamarix)) were selected from the digitized photos for separability analysis and supervised classification. Due to color similarities among the eight cover types, the average separability, based originally only on color, was very low. The separability was improved significantly through the inclusion of texture analysis. Six types of texture measures with various window sizes were evaluated. The best texture was used as an additional feature along with the color, for identifying Tamarix. A total of 29 color photographs were processed to detect Tamarix infestations using a combination of the original digital images and optimal texture features. It was found that the saltcedar covered a total of 3.96 km² (396 hectares) within the study area. For the accuracy assessment, 95 classified samples from the resulting map were checked in the field with a global position system (GPS) unit to verify Tamarix presence. The producer's accuracy was 77.89%. In addition, 157 independently located ground sites containing saltcedar were compared with the classified maps, producing a user's accuracy of 71.33%.     

彩釉砖的辐射水平及其放射防护管理

简述了我国国产彩釉砖的辐射水平、室内装修彩釉砖的限值以及它对人体产生辐射的途径，提出了放射防护管理措施和存在的问题。     

水中亚硝化细菌和硝化细菌检测方法的探讨

介绍了亚硝化细菌和硝化细菌的培养方法,并用MPN法计数亚硝化细菌和硝化细菌.对判断培养物中亚硝酸盐和硝酸盐存在的显色反应进行了对比试验.结果表明, 在NO-3的显色反应中,可用氨基磺酸铵溶液作为NO-2的抑制剂,并且要先加入二苯胺,再滴加浓硫酸,这样更便于结果观察.指出硝化细菌培养基对于显色反应没有影响,NO-2显色的质量浓度为0.15 mg/L.     

邻菲啰啉直接光度法测定水中总铁

为了准确快速测定印染企业生产用水中的铁，探讨了Fe3＋在水浴和室温25℃时的还原反应试验，发现在这2个条件下Fe3＋均能被盐酸烃胺快速还原为Fe3＋，进而提出了测定水中总铁的新方法——邻菲哕啉直接光度法。并对该方法的检出限、显色络合物的稳定性、干扰及消除、盐酸用量、校准曲线、精密度和准确度进行了试验。检出限为0．03mg／L，显色络合物显色15min可稳定6个月，精密度RSD〈4．32％，加标回收率为95．3％～103％。通过地下水、地表水、工业废水和铁标准样品的比对实验表明，邻菲哕啉直接光度法与邻菲啰啉光度法（标准法）的测定结果无显著差异。     

还原-偶氮光度法测定气体中硝基苯类的改进

因吸收液相对偏多,采气量偏少,过滤液偏少,最后参加显色反应的气体量很少,实验现象是显色溶液全部无色;如果减少吸收液,增加采气量,增加过滤液,使参加显色反应的气体增加很多,这样分析才科学、合理。