共查询到19条相似文献,搜索用时 453 毫秒
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本文将KMnO4在酸性介质中氧化As(Ⅲ )和高锰酸钾—甲氧苄啶—硫代硫酸钠化学发光反应偶合一起 ,建立了一种间接测定痕量砷含量的新方法。研究了各种反应物浓度、酸度、干扰离子等因素对测定结果的影响。As(Ⅲ )浓度在 1.0× 10 - 7~ 1.0× 10 - 5g/mL范围内与化学发光强度有较好的线性关系 .对 5 .0× 10 - 6 g/mL的As(Ⅲ )进行了 11次平行测定 ,相对标准偏差为 2 .8% ,方法的检出限为 2 .2× 10 - 9g/mL。 相似文献
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文章研究了高锰酸钾 -甲醛 -I- 化学发光体系 ,建立了一种测定环境水样中微量碘的新方法。讨论了各种反应物浓度、酸度、干扰离子等因素对测定结果的影响。I- 浓度在 1 0× 10 - 7~4 0× 10 - 6 g/mL范围内与化学发光强度有较好的线性关系。对 1 0× 10 - 6 g/mL的I- 进行了 (n =11)平行测定 ,相对标准偏差为 3 1% ,方法的检出限为 2 4× 10 - 9g/mL。结果令人满意。 相似文献
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以Ce4+ /Ce3 + 氧化还原体系作缓冲溶液 ,用流动注射电势检测法测定了维生素C ,将样品注射于以 0 .1mol/LK2 SO4作支持电解质的Ce4+ /Ce3 + 缓冲溶液试剂流 ,以流通型氧化还原电势检测电极检测维生素C与Ce4+ 反应引起的氧化还原电对的电势变化 ,对 3.0× 10 -4mol/LCe4+ / 3.0× 10 -4mol/LCe3 + 缓冲溶液 ,测定维生素C的线性范围为 1.0× 10 -4~ 6 .0× 10 -4mol/L ,检出限为 1.3× 10 -5mol/L ,相对标准偏差为 0 .36 % (n =4 ) ,分析频率为 12 0次 /小时。 相似文献
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研究了在 0 .1~ 0 .4mol/ L KOH介质中 ,用 KIO4与 Cr3 反应生成黄色产物 ,摩尔吸光系数 ε=6 .2 1× 10 3 L·mol-1·cm-1 ,最大吸收波长为 375 nm,铬 ( )含量在 0~ 8.8mg/ L符合比尔定律 ,从而建立了一种新的测定铬 ( )分光光度法 ,应用到电镀废水中铬 ( )的测定 ,结果满意。 相似文献
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本文研究了以PPA-TBP为电活性物质的PVC膜吡哌酸离子选择性电极的制备方法.在HAc-NaAc(pH=3.7)底液中,电极响应的线性范围1.0×10-3~1.0×10-5mol/L,检测限为5.0×10-6mol/L,级差为28mV/pc.并用该电极测定了吡哌酸片剂中吡哌酸的含量,结果满意. 相似文献
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高灵敏度化学发光仪的研制 总被引:3,自引:0,他引:3
本文报道高灵敏度化学发光仪的工作原理和电路系统,在NaOH-Co~(2+)-H_2O_2体系中,对ABEI标记抗-HBs进行测定,实验结果表明,发光强度与ABEI-HBs浓度具有良好线性关系,测定的检测限达5.6×10~(-10)g/mL,能够满足化学发光免疫分析法测定HBs的要求. 相似文献
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The post-chemiluminescence (PCL) phenomenon arising from the potassium periodate–luminol reaction induced by lead(II) was investigated. A strong PCL signal was observed when lead(II) was injected into the mixture of potassium periodate and luminol in a flow-cell. The influencing factors on the PCL intensity of the system were investigated. Under the optimum experimental conditions, the present method allowed the determination of lead(II) in the concentration range of 1.0 × 10?8 to 1.0 × 10?5 mol/L and the detection limit for lead(II) was 2.3 × 10?10 mol/L. The relative standard deviation was 3.2% for 11 replicate analyses of 1.0 × 10?6 mol/L lead(II). Combined with cotton cellulose xanthate for separation, the proposed method was applied to the determination of lead(II) in real water samples with satisfactory results. 相似文献
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在硫酸介质中,二苯碳酰二肼可与铬(VI)发生显色反应生成紫红色的络合物,该络合物在540 nm波长处有最大吸收峰,由此建立测定磁性材料中铬(VI)含量的分光光度分析方法。本文对测定波长、显色pH值、显色剂用量以及显色时间等实验条件进行优化,在最佳实验条件下,络合物在540nm处的吸光度值与铬(VI)的浓度在0~0.3mg/L范围内呈良好的线性关系,其线性方程为A=0.839C-0.0048(c∶mg/L),相关系数r=0.9999;检出限为3.85×10~(-4)mg/L,回收率为94%~105%。采用碱浸煮方法提取磁性材料中的铬(VI),并用该方法对样品中铬(VI)的含量进行测定,并与SGS测得的结果进行对比。结果表明,该法的测定结果与SGS测得的结果相一致。该方法具有操作简便、快捷的优点,用于磁性材料中铬(VI)的测定,所得结果令人满意。 相似文献
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在无保护性介质存在下,仅以Na_2SO_3作化学除氧剂,用KI或TlNO_3作重原子微扰剂,就能直接诱导α-萘乙酸(α-NAA)水溶液强而稳定的流体室温磷光(RTP)发射。磷光峰位波长λ_(ex)/λ_(em)分别为281/495,522nm和289/492,521nm。当体系中引入少量有机溶剂时,体系RTP强度,达到稳定所需的光诱导时间及重原子微扰剂的选择都受到较大影响。在维持乙醇或乙腈含量<1%条件下,用KI作重原子时,α-NAA的分析曲线线性范围为6.0×10~(-7)~1.6×10~(-5)mol/L和1.6×10~(-5)~8.0×10~(-5)mol/L,相关系数分别为0.999和0.997,检出限为3.6×10~(-8)mol/L。用TlNO_3作重原子时,分析曲线线性范围为6.0×10~(-7)~4.0×10~(-5)mol/L,相关系数为0.997,检出限为4.3×10~(-8)mol/L。 相似文献
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A novel flow injection method for the determination of polydatin is reported based on the inhibition of silver nitrate, luminol, and gold nanoparticles chemiluminescence. Under the optimum condition, the decrease in chemiluminescence was proportional to the concentration of polydatin from 1.0 × 10?8 to 1.0 × 10?5 mol/L. The detection limit was 2.1 × 10?9 mo1/L and the relative standard deviation was 2.1% for the determination of 1.0 × 10?6 mol/L polydatin. This method was successfully employed for the determination of polydatin in Polygonum cuspidatum roots and human urine. 相似文献
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建立一种在线消除基体、直接进样测定甲醇汽油中无机阴离子的离子色谱(IC)方法。样品经90%(V/V)甲醇溶解、稀释后直接进样,通过在线基体消除和预富集,采用IonPac AS23(250×4mm)分析柱分离,淋洗液为4.5mmol/L Na2CO3-0.8mmol/L NaHCO3,流速1.2 mL/min,采用Dionex DS6电导检测器检测,外标法定量。Cl-和SO42-的线性范围分别为0.05~5.0 mg/L,0.5~10 mg/L,相关系数分别为0.9998和0.9999,加标回收率为92.5%~96.7%,相对标准偏差RSD(n=8)<2.0%,检出限(以信噪比S/N=3计)分别为0.02 mg/L,0.08 mg/L。该方法用于甲醇汽油中无机阴离子的测定,结果令人满意。 相似文献
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Judong You 《仪器科学与技术》2013,41(5):524-534
A luminol–carboxymethyl chitosan (CMCS) system was established using flow injection chemiluminescence (CL) based on the enhancing effect of CMCS on the luminol–dissolved oxygen reaction. The CL intensity was linear with the CMCS concentration ranging from 0.01–30.0 µM. Al(III) was shown to quench the CL of the luminol–CMCS reaction, and the decrease of CL intensity was linear with the logarithm of Al(III) concentration over the range from 10–1000 pM with a detection limit of 3.5 pM (3σ). At a flow rate of 2.0 mL min?1, the analysis was performed within 30 s. The proposed CL method was successfully applied to the determination of picomole levels Al(III) in human saliva and urine after oral intake of two aluminum hydroxide tablets, with recoveries from 90.6–108.7% and relative standard deviations <3% (n = 5). The results indicated that the excreted Al(III) in saliva and urine reached its maximum values at 3 hr and 2 hr, and the total excretive ratio were 1.24 × 10?3% and 3.45% in 6 hr and 12 hr, respectively. The elimination rate constant k and the half–life time t 1/2 in human saliva and urine were 0.3747 hr?1, 1.8495 hr, 0.7132 hr?1, and 0.9717 hr, respectively. The possible CL mechanism of the luminol–CMCS–Al(III) reaction is discussed. 相似文献
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During the ECM process, the metal workpiece is dissolved and turns into sludge which contaminates the electrolyte. To realize precise ECM with high cost-effectiveness, an electrolyte treatment system which can realize reuse of the electrolyte and maintain the electrolyte quality constant is significantly important and essential. Especially, in the ECM of alloys containing a certain level of chromium, it is very likely chromium dissolves to the toxic carcinogen Cr(VI). Therefore, an electrolyte filtration system is required for removing not only the sludge but also residual toxic ions in the electrolyte for health and environment conservation reasons. In this study, activated carbon and scrap iron, which are low cost and easily available materials, were newly utilized to reduce and remove toxic Cr(VI) ions. Experiments clarified that use of activated carbon has no influence on the machining ability of NaNO3 aqueous solution serving as the electrolyte. By adjusting the pH of the electrolyte to acidic, activated carbon can remove Cr(VI) from the NaNO3 aqueous solution electrolyte to a concentration of less than 0.1 mg/L. On the other hand, scrap iron generated from metal cutting processes can be used to reduce Cr(VI) to non-toxic Cr(III). By mixing HNO3 into the electrolyte solution, the reduction efficiency of scrap iron on Cr(VI) improves significantly. 相似文献