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Kinetic Spectrophotometric Determination of Trace Titanium(Ⅳ) Based on Oxidation Discoloration of Acid Chrome Blue K with Hydrogen Peroxide 被引量:5
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作者 XIONG Yan ZHOU Zhi-rong WU Fu-hai 《Journal of China University of Mining and Technology》 EI 2007年第3期418-423,共6页
A simple and sensitive kinetic spectrophotometric method for the determination of trace amounts of titanium(IV),based upon the catalytic effect of Ti(IV) on the oxidation of acid chrome blue K (ACBK) by hydrogen perox... A simple and sensitive kinetic spectrophotometric method for the determination of trace amounts of titanium(IV),based upon the catalytic effect of Ti(IV) on the oxidation of acid chrome blue K (ACBK) by hydrogen peroxide in 0.002 mol/L sulfuric acid,is described. The reaction rate is monitored spectrophotometrically by measuring the decrease in absorbance of ACBK at 524 nm. The detection limit of the method is 1.01×10?9 g/mL,and the linear range is 0-0.048 mg/L. The influence of acidity,concentration of reactants,reaction time,reaction temperature and for-eign ions is also discussed. The optimum reaction conditions were established and some kinetic parameters determined. The apparent activation energy of the catalytic reaction is 5.32 kJ/mol. The relative standard deviation for the determi-nation of titanium(IV) at the concentration of 0.048 mg/L is calculated to be 1.31% (n = 11). In combination with sol-vent extraction separation,the method has been successfully applied to the determination of trace titanium(IV) in human hair,plant matter,tea and rock samples. The results are in good agreement with the certified values with the relative standard deviations (RSD) of 1.4%-3.5%. 展开更多
关键词 titanium(IV) kinetic spectrophotometry acid chrome blue K hydrogen peroxide
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Flow-injection Spectrophotometric Determination of Uric Acid in Urine via Prussian Blue Reaction 被引量:1
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作者 WASEEM Amir YAQOOB Mohammad +2 位作者 NABI Abdul MURTAZA Ghulam HUSSAIN Izhar 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第6期929-933,共5页
A simple and sensitive flow injection(FI) spectrophotometric method was reported for the determination of uric acid based on the reduction of Fe(III)/ferricyanide in the presence of uric acid. The in situ reduced ... A simple and sensitive flow injection(FI) spectrophotometric method was reported for the determination of uric acid based on the reduction of Fe(III)/ferricyanide in the presence of uric acid. The in situ reduced ions reacted with unreduced portion of ferricyanide/Fe(III) to form soluble Prussian blue, which was monitored at an absorption wavelength of 735 nm. The optimized conditions allow a linear calibration graph in a concentration range of 1―100 μmol/L. The relative standard deviation was in a range of 0.5%―2.5%, with a detection limit(3σ blank) of 0.3 μmol/L and a sampling frequency of 60 injection/h was obtained. The effect of common substances present in human physiological fluids on the determination of uric acid was examined. The method was applied to determining uric acid in human urine samples with the recoveries in a range of 96%―105%. The results agree well with those by spectrophotometric reference method at a confidence level of 95%. Spectrophotometric procedures for uric acid determination in clinical samples were reviewed briefly. 展开更多
关键词 Flow injection analysis spectrophotometry Uric acid Prussian blue URINE
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Catalytic-kinetic spectrophotometric determination of vanadium (V) based on the Celestine blue-bromate-vanadium (V)-citric acid reaction
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作者 Ramazan Gürkan Olcay Gürkan 《Rare Metals》 SCIE EI CAS CSCD 2011年第4期348-358,共11页
A novel sensitive and relatively selective kinetic method is presented for the determination of V(V) based on its catalytic effect on the oxidation reaction of Celestine blue by potassium bromate in the presence of ... A novel sensitive and relatively selective kinetic method is presented for the determination of V(V) based on its catalytic effect on the oxidation reaction of Celestine blue by potassium bromate in the presence of citric acid as an activator. The reaction was monitored spectropho- tometrically by measuring the decrease in absorbance of Celestine blue at a maximum absorption wavelength of 540 nm between 0.5 and 9 min (the fixed-time method) in an H3PO4 medium at 45℃. The effect of various parameters such as concentrations of H3PO4, citric acid, potassium bromate and Celestine blue, ionic strength, reaction temperature and time on the rate of V(V) catalyzed reaction was studied. The method is free from the most interferences, especially from large amounts of V(IV). The decrease in absorbance is proportional to the concentration of V(V) over the entire concentration range tested (0.025-1.25 lag.mL^-1) with a detection limit of 6.80 tag.L^-1 (according to statistical 3Sblank/k criterion) and a coefficient of variation (CV) of 1.78% (for ten replicate measurements at 95% confidence level). The proposed method suffers from a few interferences such as Cr(VI) and Hg(Ⅱ) ions. The method was successfully applied to the determination of V(V) in river water, lake water, tap water, natural drinking water samples and a certified standard reference material such as SRM-1640 with satis- factory results. The vanadium contents of natural water samples were detected by using both linear calibration curve and standard addition curve methods. The recoveries of spiked vanadium (V) into the certified standard water sample were found to be quantitative, and the reproducibility was satisfactory. It was observed that the results of the SRM 1640 were in good agreement with the certified value. 展开更多
关键词 catalytic effect VANADIUM spectrophotometry BROMATES Celestine blue citric acid
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亚甲蓝分光光度法测定水中阴离子表面活性剂含量的方法改进 被引量:2
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作者 王秋实 吴林源 +3 位作者 张诗委 袁哲 张可佳 赵海谦 《理化检验(化学分册)》 CAS CSCD 北大核心 2024年第1期93-96,共4页
对亚甲蓝分光光度法(GB 7494—1987)测定水中阴离子表面活性剂含量进行了方法改进。以毒性相对较小的二氯甲烷取代三氯甲烷作为萃取剂,试管取代分液漏斗,利用振荡器进行萃取。结果表明:改进方法的最佳萃取时间为1.5 min,单个样品的分析... 对亚甲蓝分光光度法(GB 7494—1987)测定水中阴离子表面活性剂含量进行了方法改进。以毒性相对较小的二氯甲烷取代三氯甲烷作为萃取剂,试管取代分液漏斗,利用振荡器进行萃取。结果表明:改进方法的最佳萃取时间为1.5 min,单个样品的分析时间在10 min以内;十二烷基苯磺酸钠标准曲线的线性范围在2.0 mg·L^(-1)以内,检出限(3s/k)为0.0297 mg·L^(-1);对十二烷基苯磺酸钠标准溶液重复测定6次,测定值的相对标准偏差(n=6)均小于9.0%;对空白样品进行加标回收试验,回收率为95.0%~99.1%。 展开更多
关键词 亚甲蓝分光光度法 方法改进 阴离子表面活性剂 测定
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沉积岩中黄铁矿含量及其硫同位素组成连续测定方法研究
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作者 韩娟 刘汉彬 +5 位作者 金贵善 张建锋 石晓 李军杰 张佳 刘小桐 《世界核地质科学》 CAS 2024年第1期73-81,共9页
沉积岩中黄铁矿的含量和硫同位素组成研究可以用于判断沉积环境特征,反演成岩成矿过程。设计了一套多通道的黄铁矿硫提取装置,确定了装置的加热温度为130℃,实验时间为2h,优化了实验流程,实现一次提取同时满足黄铁矿含量及其同位素组成... 沉积岩中黄铁矿的含量和硫同位素组成研究可以用于判断沉积环境特征,反演成岩成矿过程。设计了一套多通道的黄铁矿硫提取装置,确定了装置的加热温度为130℃,实验时间为2h,优化了实验流程,实现一次提取同时满足黄铁矿含量及其同位素组成测定需要。采用亚甲基蓝分光光度法测定硫含量和元素分析仪-气体同位素质谱法测定黄铁矿硫同位素组成。亚甲基蓝分光光度法的标准曲线的线性相关性R^(2)=0.9999,黄铁矿样品的加标回收率介于94%~100%之间,10次测量的相对标准偏差为1.9%。黄铁矿经过铬还原法提取生成的硫化银的硫同位素组成的测试结果和本身的测试结果在误差范围内一致,精度≤0.2‰,可以满足沉积岩中黄铁矿硫同位素测试需求。 展开更多
关键词 沉积岩 黄铁矿含量 硫同位素组成 亚甲基蓝分光光度法 元素分析仪-气体同位素质谱法
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过氧化氢-耐尔蓝体系催化动力分光光度法测定冶炼废水中微量铜 被引量:1
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作者 许维 龙青梅 《中国无机分析化学》 北大核心 2024年第3期286-291,共6页
随着水土环境的日益恶化,监控包括铜在内的重金属污染对水土环境的危害越来越受到重视,有的重金属通过食物链以有害浓度在人体内积累,严重危害人体健康。基于在柠檬酸缓冲溶液反应介质中,过氧化氢在Cu(Ⅱ)的催化下能氧化耐尔蓝褪色,其... 随着水土环境的日益恶化,监控包括铜在内的重金属污染对水土环境的危害越来越受到重视,有的重金属通过食物链以有害浓度在人体内积累,严重危害人体健康。基于在柠檬酸缓冲溶液反应介质中,过氧化氢在Cu(Ⅱ)的催化下能氧化耐尔蓝褪色,其褪色程度与Cu(Ⅱ)含量成正比,从而建立了催化分光光度法测定微量Cu(Ⅱ)的新方法。选择的反应介质柠檬酸缓冲溶液具有某些表面活性剂的作用,浅析了柠檬酸缓冲溶液在工作中对耐尔蓝起增敏作用的原因,且柠檬酸作为植物提取物,具有无毒环保,易于分解,可调节酸度和化学性质稳定等优点。通过实验确定了方法的最大吸收波长为635 nm,柠檬酸缓冲溶液的最佳使用量为1.0 mL,耐尔蓝和过氧化氢的最佳用量分别为1.75和1.0 mL,反应时间和反应温度分别为11 min和90℃,Cu(Ⅱ)含量在0~0.32μg/mL内与吸光度的差值呈线性关系。对铜标准溶液和标准物质进行测定,测定结果的相对误差在2.8%~3.8%,相对标准偏差在3.8%~4.7%,表观摩尔吸光系数为5.0×10^(6)L/(mol•cm)。方法用于废水中微量Cu(Ⅱ)的测定,加标回收率在95.6%~102%。方法具有操作简便、选择性较好、有较灵敏度高、分析成本低、使用的试剂较为环保等优点。 展开更多
关键词 过氧化氢 耐尔蓝 催化动力分光光度法 微量铜
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水样阴离子表面活性剂的几种测定方法的比较 被引量:1
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作者 冉雪菲 李晴 《山西化工》 CAS 2024年第2期93-94,117,共3页
本文对亚甲蓝分光光度法、流动注射-亚甲蓝分光光度法、高效液相色谱法三种不同的监测方法在水样阴离子表面活性剂检测中的测定方法有效性做出研究。在对三种方法进行接手后,制备水体样品对三种方法效率极性对比,并基于结果论证最具有... 本文对亚甲蓝分光光度法、流动注射-亚甲蓝分光光度法、高效液相色谱法三种不同的监测方法在水样阴离子表面活性剂检测中的测定方法有效性做出研究。在对三种方法进行接手后,制备水体样品对三种方法效率极性对比,并基于结果论证最具有可行性的水样阴离子表面活性剂检测方法,以供我国相关单位借鉴与参考。 展开更多
关键词 阴离子表面活性剂 亚甲蓝分光光度法 高效液相色谱法
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亚甲基蓝分光光度法测定土壤和沉积物中硫化物研究
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作者 程瑾 《福建分析测试》 CAS 2024年第5期51-54,59,共5页
本文针对土壤中硫化物的分析方法,运用亚甲基蓝分光光度法展开了深入探讨。实验过程显示,当取样量固定为20.0 g时,本方法具有高度灵敏性,检出限低至0.04 mg/kg;精密度与准确度测定结果显示,本方法相对标准偏差小于10.0%,加标回收率广泛... 本文针对土壤中硫化物的分析方法,运用亚甲基蓝分光光度法展开了深入探讨。实验过程显示,当取样量固定为20.0 g时,本方法具有高度灵敏性,检出限低至0.04 mg/kg;精密度与准确度测定结果显示,本方法相对标准偏差小于10.0%,加标回收率广泛稳定于60%~110%。因此,可以得出结论:此法操作便捷、速度快、精度高,对于土壤及沉淀物样品中硫化物的分析具有极高的适用性。 展开更多
关键词 亚甲基蓝分光光度法 土壤和沉积物 硫化物分析
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快速有效的亚甲基蓝法检测肝素效价
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作者 周靖原 张锐 +4 位作者 屈秋红 王旭 汤继桂 郑世君 胡俊文 《广州化工》 CAS 2024年第15期72-75,共4页
通过实验分析亚甲基蓝与肝素的络合关系,讨论反应时间、溶液pH值、蛋白质的影响,建立一种快速、有效地检测肝素效价的方法。试验确定了分析波长为664 nm,且在0.09~0.54 IU/mL范围内的肝素与10 mg/L亚甲基蓝呈现良好的线性关系。反应时间... 通过实验分析亚甲基蓝与肝素的络合关系,讨论反应时间、溶液pH值、蛋白质的影响,建立一种快速、有效地检测肝素效价的方法。试验确定了分析波长为664 nm,且在0.09~0.54 IU/mL范围内的肝素与10 mg/L亚甲基蓝呈现良好的线性关系。反应时间在30~180 min范围内具有良好的稳定性;且该方法在pH=5~11范围内,1~30 mg/L牛血清蛋白(BSA)的干扰下仍保持较好的稳定性。对比实验中亚甲基蓝测肝素的方法与羊血浆法相差不大。该肝素检测方法简单、快速、经济、有效。 展开更多
关键词 效价 分光光度法 亚甲基蓝 粗品肝素
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亚甲蓝分光光度法测定水中阴离子表面活性剂的研究
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作者 蔡惠娟 《山西化工》 CAS 2024年第10期68-70,共3页
本文主要通过优化国标亚甲蓝分光光度法测试待测水样的前处理过程中的过滤、破乳化以及萃取方法,以期简化实验流程,改善繁复萃取,试剂消耗,减少实验用品对结果的干扰。使用简化后的亚甲蓝分光光度法测定地表水和污水厂出水中的阴离子表... 本文主要通过优化国标亚甲蓝分光光度法测试待测水样的前处理过程中的过滤、破乳化以及萃取方法,以期简化实验流程,改善繁复萃取,试剂消耗,减少实验用品对结果的干扰。使用简化后的亚甲蓝分光光度法测定地表水和污水厂出水中的阴离子表面活性剂含量。从实验结果可以看出,该方法具有良好的精密度和准确度,检测效果与国标法没有明显的差异。 展开更多
关键词 亚甲蓝分光光度法 阴离子表面活性剂 相对标准偏差 精密度 准确度
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高浓度氨对靛酚蓝分光光度法显色的影响研究
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作者 鲍康生 《皮革制作与环保科技》 2024年第15期85-86,89,共3页
本文采用靛酚蓝分光光度法对不同浓度的氨溶液进行试验,并探讨在民用建筑工程室内空气氨检测的实际应用中经常出现数据偏低现象的原因。通过试验得知,显色反应受氨浓度的影响较为明显。当氨浓度超过7.6μg/mL时,溶液的吸光度迅速降低;... 本文采用靛酚蓝分光光度法对不同浓度的氨溶液进行试验,并探讨在民用建筑工程室内空气氨检测的实际应用中经常出现数据偏低现象的原因。通过试验得知,显色反应受氨浓度的影响较为明显。当氨浓度超过7.6μg/mL时,溶液的吸光度迅速降低;当氨溶液浓度超过120.0μg/mL时,吸光度值低于0.030,溶液的颜色趋近于浅黄色,不予显色;采用靛酚蓝分光光度法测定氨时,氨的浓度不宜超过15μg/mL,且稀释倍数不宜超过2.5倍。 展开更多
关键词 靛酚蓝分光光度法 浓度 显色反应
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阴离子表面活性剂亚甲基蓝分光光度法萃取研究
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作者 朱静 范佳荟 +2 位作者 孙思 王真真 肖威 《绿色科技》 2024年第18期99-103,共5页
阴离子表面活性剂因其对水质的恶劣影响被作为常规环境实验室必备的监测项目。现行最常用的分析方法《水质阴离子表面活性剂的测定亚甲蓝分光光度法》(GB/T 7494—1987)需要对水样进行多次萃取,萃取效果直接影响样品吸光度及测定结果的... 阴离子表面活性剂因其对水质的恶劣影响被作为常规环境实验室必备的监测项目。现行最常用的分析方法《水质阴离子表面活性剂的测定亚甲蓝分光光度法》(GB/T 7494—1987)需要对水样进行多次萃取,萃取效果直接影响样品吸光度及测定结果的精密度准确度。通过对方法空白、自控样结果的比较确定了在振荡时间50 s,频率300 r/min的参数下能达到完全萃取效果,且手工萃取和仪器自动萃取结果并无明显差异。仪器自动萃取空白加标的加标回收率在95%~100%,相对标准偏差为1.9%,准确度精密度均合格。另外实验中发现,计量院标液绘制的曲线斜率会明显高于生态环境部标液绘制的曲线,建议使用相同来源的标液和自控样进行实验。 展开更多
关键词 阴离子表面活性剂 亚甲基蓝分光光度法 萃取 条件优化
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Application of potassium ferricyanide in the spectrophotometric determination of captopril 被引量:4
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作者 Shi Lei Wang Min Wang Quan Min Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第1期88-91,共4页
A novel method for the determination of captopril by spectrophotometer is described in this paper. The experiment is based on the fact that Fe(Ⅲ) is reduced to Fe(Ⅱ) by captopril, then the in sire formed Fe(Ⅱ... A novel method for the determination of captopril by spectrophotometer is described in this paper. The experiment is based on the fact that Fe(Ⅲ) is reduced to Fe(Ⅱ) by captopril, then the in sire formed Fe(Ⅱ) reacts with potassium ferricyanide to give the soluble prussian blue at pH 4.00, and its maximal adsorption wavelength (λmax) is 735 nm. Good linear relationship is obtained between the absorbance and the concentration of captopril in the wide range of 0.05-20 μg/mL. The linear regression equation is A = -0.04314 + 0.11423C (μg/mL) with a correlation coefficient R = 0.9998. The detection limit (3σ/k) is 0.04 μg/mL, the molar absorption coefficient is 2.5×10^4 L/mol cm. By mensurating the absorbance of soluble prussian blue, the indirect determination of captopril can be obtained. This method has been successfully applied to determination of captopril in pharmaceutical samples. Analytical results obtained are satisfactory. 展开更多
关键词 Potassium ferricyanide CAPTOPRIL Prussian blue spectrophotometry
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Flow injection spectrophotometric determination of vitamin E in pharmaceuticals,milk powder and blood serum using potassium ferricyanide-Fe(Ⅲ) detection system 被引量:3
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作者 Saima Jadoon Amir Waseem +1 位作者 Mohammad Yaqoob Abdul Nabi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第6期712-715,共4页
A simple and sensitive flow injection spectrophotometric method is reported for the determination of vitamin E using potassium ferricyanide-Fe(Ⅲ) detection system.In the presence of vitamin E,Fe(Ⅲ)/ferricyanide redu... A simple and sensitive flow injection spectrophotometric method is reported for the determination of vitamin E using potassium ferricyanide-Fe(Ⅲ) detection system.In the presence of vitamin E,Fe(Ⅲ)/ferricyanide reduces.The in situ reduced ions are then reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to make soluble Prussian blue,which is monitored at absorption wavelength of 735 nm.Linear calibration graph was obtained in the concentration range of 0.1-40μg mL^(-1).The relative standard deviations (n=4) were in the range of 1.1-3.6%,with limits of detection(3 s blank) of 0.04μg mL^(-1).The proposed method allowed 12 injections h^(-1).The method is applied to determine vitamin E in pharmaceuticals,infant milk and blood serum samples using hexane extraction with the recoveries in the range of 93±3 to 97.5±4%.The method is validated using certified reference materials SRM 968c for blood serum samples. 展开更多
关键词 Flow injection spectrophotometry Vitamin E Prussian blue FE(III) FERRICYANIDE Pharmaceuticals Blood serum
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A Kinetic Spectrophotometric Method for the Determination of Iron (Ⅲ) in Water Samples 被引量:7
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作者 JI Hongwei XU Jian XIN Huizhen YANG Xiaoman 《Journal of Ocean University of China》 SCIE CAS 2008年第2期161-165,共5页
A new kinetic spectrophotometric method has been developed for the determination of iron (Ⅲ). The method is based on the catalytic effect of iron (Ⅲ) on the oxidation of weak acid brilliant blue dye (RAWL) by ... A new kinetic spectrophotometric method has been developed for the determination of iron (Ⅲ). The method is based on the catalytic effect of iron (Ⅲ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The advantages of the proposed method are that it is sensitive, accurate, rapid, inexpensive, can be operated under room temperature and has a large determination concentration range compared to other techniques. The obtained optimum conditions are: pH 3.15, RAWL (200 mgL^-1) 5.00mL, Potassium periodate solution (0.01 molL^-1) 0.30mL, phenanthroline (0.02 molL^-1) 1.00mL, reaction temperature 25℃ and reaction time 7 min. With this method iron could quantitively be determined in the range 0.00-0.02 mgL^-1, the detection limit being 4.10 × 10^10gmL^-1. The relative standard deviations (RSD) in five replicate determinations for 3 μgL^-1and 5 μgL^-1 iron (Ⅲ) are 3.1% and 1.9%, respectively. The method has been applied to the determination of iron (Ⅲ) in tap water samples and seawater samples (from the South China Sea), the recovery rates being 98.0% and 100.5%, respectively. 展开更多
关键词 IRON kinetic spectrophotometry catalytic effect weak acid brilliant blue dye (RAWL)
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Flow-injection Determination of Cysteine,N-Acetyl Cysteine and Glutathione in Pharmaceuticals via Potassium Ferricyanide-Fe(Ⅲ) Spectrophotometric System 被引量:1
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作者 WASEEM Amir YAQOOB Mohammad NABI Abdul 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第6期893-898,共6页
A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe(Ⅲ)/ferricyanide,the in situ reduced ions are reacted wi... A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe(Ⅲ)/ferricyanide,the in situ reduced ions are reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to form soluble Prussian blue,which is monitored at 735 nm.The calibration graphs are linear in the concentration ranges of(1―100)×10-6 mol/L for cysteine and N-acetyl cysteine,and(1―50)×10-6 mol/L for glutathione.The relative standard deviations of 1.8%,2.5% and 1.9% were found for eleven replicate analyses of 5×10-6 mol/L cysteine,N-acetyl cysteine and glutathione.The limits of detection(3σ blank) at 5×10-7 mol/L for cysteine,and 3×10-7 mol/L for N-acetyl cysteine and glutathione were obtained.The proposed method allowed 60 injections/h.The effects of common substances present in pharmaceuticals and human physiological fluids were examined.The method was applied to determining cysteine in pharmaceutical formulations with the recoveries in a range of 97% to 106% and the results obtained are agreed well with labeled values. 展开更多
关键词 Flow injection spectrophotometry CYSTEINE Prussian blue Fe(Ⅲ) FERRICYANIDE PHARMACEUTICAL
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A novel indicator system for catalytic spectrophotometric determination and speciation of inorganic selenium species (Se(Ⅳ), Se(Ⅵ)) at trace levels in natural lake and river water samples 被引量:1
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作者 Ramazan Gürkan Halil brahim Ulusoy +1 位作者 Mehmet Akay Pinar Bulut 《Rare Metals》 SCIE EI CAS CSCD 2011年第5期477-487,共11页
A novel catalytic kinetic method is proposed for the determination of Se(Ⅳ), Se(Ⅵ), and total inorganic selenium in water based on the catalytic effect of Se(Ⅳ) on the reduction of Celestine blue by sodium su... A novel catalytic kinetic method is proposed for the determination of Se(Ⅳ), Se(Ⅵ), and total inorganic selenium in water based on the catalytic effect of Se(Ⅳ) on the reduction of Celestine blue by sodium sulfide at pH 7.0 phosphate buffer. The fixed-time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the two calibration graphs are linear with a good correlation coefficient in the range 2-20 and 20-200 μg·L-1 of Se(Ⅳ) for the fixed-time method at 30℃. The experimental and theo- retical detection limits of the developed kinetic method were found to be 0.21 and 2.50 μg·L-1 for the fixed-time method (3 min). All of the variables that affect the sensitivity at 645 nm were investigated, and the optimum conditions were established. The interference effect of various cations and anions on the Se(Ⅳ) determination was also studied. The selectivity of the selenium determination was greatly improved with the use of the strongly cation exchange resin such as Amberlite IR120 plus as long as chelating agents of thiourea and thiosulphate. The proposed kinetic method was validated statistically and through recovery studies in natural water samples. The relative standard deviations (RSDs) for ten replicate measurements of 2, 10, and 20 μg·L-1 of Se(Ⅳ) change between 0.35% and 5.58%, while the RSDs for ten replicate measurements of 3, 6, and 12 μg·L-1 of Se(Ⅵ) change between 0.49% and 1.61%. Analyses of a certified standard reference material (NIST SRM 1643e) for selenium using the fixed-time method showed that the proposed kinetic method has good accuracy. The Se(Ⅳ), Se(Ⅵ), and total inorganic selenium in lake and river water samples have been successfully determined by this method after selective reduction of Se(Ⅵ) to Se(Ⅳ). 展开更多
关键词 selenium speciation Celestine blue catalytic effect kinetic spectrophotometry natural waters
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催化光度法测定伊文思蓝褪色反应速率常数——推荐一个物理化学新实验
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作者 徐俊晖 戢凌俊 +3 位作者 孙琳 杨玉蓉 钟敏 王亚珍 《大学化学》 CAS 2023年第10期266-273,共8页
介绍了一个关于复杂反应动力学测量的物理化学实验。基于亚硝酸钠作用下溴酸钾氧化伊文思蓝褪色反应,通过测量不同初始反应条件下系统吸光度随时间的变化情况,推导伊文思蓝和溴酸钾的分级数,探讨亚硝酸钠对反应的加速作用,并根据不同温... 介绍了一个关于复杂反应动力学测量的物理化学实验。基于亚硝酸钠作用下溴酸钾氧化伊文思蓝褪色反应,通过测量不同初始反应条件下系统吸光度随时间的变化情况,推导伊文思蓝和溴酸钾的分级数,探讨亚硝酸钠对反应的加速作用,并根据不同温度下的测量数据计算表观反应活化能。本实验可依据学时安排开设为基础性实验或综合设计性实验。两个学期的教学实践表明,作为综合设计性实验,本实验可加强学生对表观速率常数、表观活化能以及催化作用的认识,并促进学生综合实验能力的培养;此外,本实验也可适当精简后作为基础性实验项目“丙酮碘化反应”的替代方案,能克服该实验中存在的反应速率较快不易记录实验数据、碘不易清洗污染比色皿等问题。 展开更多
关键词 催化光度法 伊文思蓝 表观速率常数 表观活化能
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ACBK光度法测定镍
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作者 杨卓 朱薛轲 杨红兵 《广州化工》 CAS 2023年第15期67-69,共3页
在pH 10.38的Britton-Robison缓冲介质中,硫酸镍与酸性铬兰K(ACBK)共存时,溶液变为紫色,在516 nm、548~554 nm附近各产生一个新的吸收峰,600 nm处出现明显的褪色现象。考察了体系最适宜的实验条件,发现:在516 nm、600 nm处ACBK-Ni^(2+)... 在pH 10.38的Britton-Robison缓冲介质中,硫酸镍与酸性铬兰K(ACBK)共存时,溶液变为紫色,在516 nm、548~554 nm附近各产生一个新的吸收峰,600 nm处出现明显的褪色现象。考察了体系最适宜的实验条件,发现:在516 nm、600 nm处ACBK-Ni^(2+)体系的ΔA与硫酸镍浓度均具有良好的线性关系,其中600 nm处的线性关系最好,r为0.9974,ΔA=0.1191-0.1297 c,用于环境水样中Ni^(2+)含量的测定,回收率为99.5%~106.4%,RSD为1.0%~1.2%,结果可靠,由此建立了一种测定环境中Ni^(2+)含量的光度法。 展开更多
关键词 硫酸镍 光度法 酸性铬兰K
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锰(Ⅱ)–酸性铬蓝K体系吸收光谱研究及其分析应用
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作者 杨卓 李文秀 《山东化工》 CAS 2023年第16期169-173,176,共6页
在pH值9.15的Britton-Robison缓冲溶液中,锰(Ⅱ)与酸性铬蓝K共存时,溶液由蓝色变为玫红色,在506 nm和537 nm处产生新的吸收峰,596 nm处的吸收明显减弱。探究了反应的适宜条件、光谱特征、灵敏度和选择性,发现:体系在506,537和596 nm处的... 在pH值9.15的Britton-Robison缓冲溶液中,锰(Ⅱ)与酸性铬蓝K共存时,溶液由蓝色变为玫红色,在506 nm和537 nm处产生新的吸收峰,596 nm处的吸收明显减弱。探究了反应的适宜条件、光谱特征、灵敏度和选择性,发现:体系在506,537和596 nm处的△A与Mn(Ⅱ)浓度c均具有良好的线性关系和较高的灵敏度,其中596 nm处的灵敏度最高,ε为8.34×10^(4) L·moL^(-1)·cm^(-1),用于人发中锰(Ⅱ)含量的测定,回收率达98.8%~103.2%,相对标准偏差为2.1%~2.5%,结果令人满意,据此建立了一种测定锰(Ⅱ)含量的褪色光度法。 展开更多
关键词 锰(Ⅱ) 酸性铬蓝K 光度法
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