共查询到18条相似文献,搜索用时 93 毫秒
1.
光度法测定小麦面粉中过氧化苯甲酰 总被引:7,自引:0,他引:7
在磷酸介质中,过氧化苯甲酰氧化碘化钾生成的碘与淀粉显色,在585nm波长处有最大吸收峰,建立了碘化钾碘蓝光度法间接测定微量过氧化苯甲酰的方法。过氧化苯甲酰的质量浓度在0.016g·L^-1以内呈线性。方法应用于新出产的小麦面粉中过氧化苯甲酰的测定,回收率在93.3%以上。 相似文献
2.
稳定回归法用于复方氯丙嗪片的测定 总被引:1,自引:1,他引:1
本文应用稳定回归法用于紫外重叠光谱的分析。以复方氯丙嗪为例,不经分离,测定了盐酸氯丙嗪和盐酸异丙嗪的含量。与最小二乘回归法比较,提高了测定结果的准确度和精密度。结果满意。 相似文献
3.
4.
研究了在硫酸介质中,IO3-能与盐酸氯丙嗪发生氧化显色反应,且显色的程度和IO3-的量成正比例关系,据此建立了分光光度法测定食盐中碘含量的分析方法。显色物质的最大吸收波长为526nm,线性回归方程为y=1.214x+0.011 8,相关系数为0.998 9,表观摩尔吸光系数为5.2×104 L/(mol·cm),碘浓度在0~24μg/10mL范围内有良好的线性关系,相对标准偏差为1.2%~2.2%,加标回收率为97.5%~102.0%,实验表明,方法操作简单,灵敏度高、选择性好,适用于食盐中碘含量的测定。 相似文献
5.
王晓玲 《中国无机分析化学》2015,5(3)
;本文研究了在硫酸介质中,IO3-能与盐酸氯丙嗪发生氧化显色反应,且显色的程度和IO3-的量成正比例关系,据此建立光度法测定食盐中碘含量的分析法。显色物质的最大吸收波长为526 nm,线性回归方程为y=1.214x 0.0118,相关系数为0.9989,表光摩尔吸光系数为5.2×104L.mol-1.cm-1, 碘浓度在0~24 μg /10mL范围内有良好的线性关系,该法操作简单,灵敏度高、选择性好,用于食盐中碘含量的测定,相对标准偏差为1.2%~2.2%,回收率为97.5.%~102%。 相似文献
6.
紫外分光光度法同时测定面粉中过氧化苯甲酰及其还原产物苯甲酸的含量 总被引:4,自引:0,他引:4
建立了一种测定面粉中过氧化苯甲酰及其还原产物苯甲酸含量的紫外分光光度法。采用无水乙醇作参比,在同一样品溶液中分别于233 nm和226 nm处同时测定过氧化苯甲酰及其还原产物苯甲酸的含量,由于两组分同时测定时相互影响,通过建立线性方程组的方法消除被测组分间的相互干扰,过氧化苯甲酰在8.26×10-6~4.95×10-6mol/L和苯甲酸在1.64×10-5~9.84×10-5mol/L范围内服从比耳定律。该法操作简便、快速,不经提取分离同时测定面粉中过氧化苯甲酰及其还原产物苯甲酸含量获得了较满意的结果。 相似文献
7.
8.
在中性或弱酸性中,氨存在条件下亚硫酸盐与邻苯二甲醛生成强荧光物质,而过氧化苯甲酰对该荧光物质具有抑制作用。基于该原理建立了一种简单、灵敏测定面粉中微量过氧化苯甲酰的荧光光度法。荧光物质的最大激发波长和发射波长分别为326、389 nm。方法检出限为0.23μg/mL,线性范围为0.8~8.0μg/mL,线性回归方程为ΔF=20.589c 2.8805,相关系数r=0.999 0。该法用于测定面粉中微量过氧化苯甲酰含量的相对标准偏差为1.34%~2.32%,回收率为95.4%~101.1%。 相似文献
9.
建立了以紫尿酸为显色剂测定盐酸氯丙嗪的光度法。在弱酸性条件下,Fe(Ⅲ)被盐酸氯丙嗪定量还原成Fe(Ⅱ),Fe(Ⅱ)在碱性条件下与紫尿酸反应形成不稳定的蓝色配阴离子,该配阴离子与盐酸氯丙嗪形成稳定的蓝色离子缔合物,该离子缔合物的最大吸收波长位于635 nm,其表观摩尔吸光系数ε=2.62×104 L/(mol·cm),盐酸氯丙嗪质量浓度在0.5~10.0 mg/L范围内与体系的吸光度呈良好的线性关系,线性相关系数为0.999 2。测定结果的相对标准偏差为1.02%~2.65%(n=5),加标回收率为91.0%~95.0%。该法灵敏度较高、选择性及重现性良好,可用于片剂中盐酸氯丙嗪含量的测定。 相似文献
10.
王晓玲 《中国无机分析化学》2014,4(4):57-59
研究了在盐酸介质中,三价铁离子能将盐酸氯丙嗪氧化成一种红色的物质,且氧化的程度与盐酸氯丙嗪的量呈正比关系,据此建立了测定盐酸氯丙嗪的分光光度分析方法。实验中最大吸收波长为530nm,摩尔吸光系数为5.13×103 L/(mol·cm),盐酸氯丙嗪的量在5~250μg/10mL范围内与吸光度A有良好的线性关系,方法用于盐酸氯丙嗪药物的测定,其相对标准偏差为0.11%~0.19%,加标回收率为95.0%~97.0%。 相似文献
11.
面粉中增白剂过氧化苯甲酰的示差脉冲伏安法测定 总被引:4,自引:2,他引:2
研究了以二氯甲烷作为萃取剂,二氯甲烷-乙酸(1.5×10-2mol/L)为底液,四丁基高氯酸铵(0.01mol/L)为支持电解质,玻碳电极作为工作电极,采用示差脉冲伏安法测定过氧化苯甲酰。过氧化苯甲酰的阴极峰电位为-0.045V(vs.Ag/AgCl),峰电流与过氧化苯甲酰浓度在2.5×10-6~1.0×10-4mol/L范围内呈良好的线性关系,检出限为2.5×10-7mol/L。本法可直接用于小麦面粉中增白剂过氧化苯甲酰的测定。 相似文献
12.
13.
14.
15.
过氧化苯甲酰的热分解研究 总被引:5,自引:0,他引:5
The thermal decomposition process of benzoyl peroxide was investigated by Accelerating Rate Calorimeter. The curves of thermal decomposition temperature and pressure versus time for the systems were obtained. The curves of temperature rising-rate versus thermal decomposition temperature were also obtained. After the data revision disposal and analysis processing, thermal decomposition parameters and kinetic data of benzoyl peroxide were calculated, respectively. 相似文献
16.
C. A. Barson J. C. Bevington 《Journal of polymer science. Part A, Polymer chemistry》1997,35(14):2955-2960
There has been a suggestion that, for polymerizations initiated by benzoyl peroxide, the use of benzene as diluent may cause uncertainties about the conclusions reached from studies of the end groups in the resulting polymers. It is now shown that no substantial changes are caused by the replacement of benzene by other solvents. This finding contributes to the conclusion that any capture of benzoyloxy radicals by benzene is only transitory and does not invalidate the deductions made from the results of analyses of polymers for benzoate and phenyl end groups derived from the peroxide. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2955–2960, 1997 相似文献
17.
A novel capillary microliter order droplet injection-chemiluminescence (CL) system is proposed. In this system, the liquid sample microdrops, automatically formed at the end of a capillary tip by the effect of the gravity and the gas pressure, repeatedly drop into the miniature reaction cell and reacts with CL reagent to generate CL signal. The phenomena of sample zone dilution and spreading are eliminated as the capillary is used as the sample channel and gas pressure is used as driving force without the liquid carrier stream. Therefore, a high sensitivity is obtained. To evaluate the applicability of the proposed method, a determination of benzoyl peroxide (BP) is examined. The system shows that the benzoyl peroxide is detected linearly in the concentration range from 5×10−10 to 1×10−6 g ml−1. The detection limit (signal-to-noise ratio=3) is 1.4×10−10 g ml−1 for benzoyl peroxide (mass concentration is 1.1 pg, i.e., 4.5 fmol), which is the best result reported so far. The relative standard deviation (n=11) is 1.5% for 2.0×10−8 g ml−1 BP. The proposed detector for the detection of benzoyl peroxide offers the advantages of sensitivity, simplicity, rapidity, automation and miniaturization. The proposed method has been applied satisfactorily to the determination of benzoyl peroxide in wheat flour. 相似文献
18.
Jozef Rychlý Aysegul Kocer Fathy Tanis Lyda Matisová-Rychlá Ivica Janigová Katarína Csomorová 《Chemical Papers》2009,63(4):471-478
Difference in the kinetics of chemiluminescence (CL) and differential scanning calorimetry records for decomposition of originally
solid benzoyl peroxide continuing as a melt reaction was outlined. While the main portion of heat measured by DSC is released
in the spontaneous decomposition of benzoyl peroxide starting as a homolytic scission of peroxidic bonds, the CL light emission
in oxygen comes presumably from the subsequent disproportionation reaction of polyphenyl peroxyl radicals and monitors the
induced decomposition of peroxide. Thermogravimetry revealed that oxygen remains partially bound to the products of benzoyl
peroxide decomposition. 相似文献