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镁,铝的激光—时间分辨荧光测定 总被引:2,自引:0,他引:2
本文报道了用8-羟基喹啉-5-磺酸作荧光指示剂,采用激光-时间分辨技术进行镁、铝测定的新方法。在1-100μg/L的范围内,镁、铝的浓度和荧光强度呈良好的线性关系,方法的检出限分别为2μg/L和1μg/L。用标准牛肝粉对方法进行了验证,并用该方法对自来水进行直接测试。 相似文献
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8—羟基喹啉萃取光度法测定氯化钠中微量镁的研究与应用 总被引:3,自引:0,他引:3
研究用8-羟基喹啉,氯仿萃取光度法测定试剂氯化钠和电解精盐水中微量镁,在酒石酸盐介质中,控制PH10.5-11.5,利用氯仿分层,能有效地排除氯化钠对测定的干扰,方法简便,快速,能增加取样量降低测定下限,可测定出试剂中0.00001%及电解精盐水中0.05ug/mlo^-1的镁含量。 相似文献
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偶氮胂-DCS作为钙镁络合滴定指示剂的研究及其应用 总被引:1,自引:0,他引:1
研究了利用光度显色剂偶氮胂-DCS作为钙镁联合滴定指示剂的可能性及使用该指示剂滴定钙镁的准确性,与常用的钙镁络合滴定指示剂进行了比较,并成功地应用于水泥试样中钙镁含量测定。结果表明,偶氮胂-DCS是一种良好的钙镁络合滴指示剂。 相似文献
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研究了新荧光试剂7-(2,4-二羟基-5-羧基苯偶氮)-8-羟基喹啉-5-磺酸(DHCBAQS)与镁形成配合物的荧光性能,在pH9.0的硼砂缓冲介质中,试剂与镁形成1:1配合物,其λex/λcm=358nm/502nm。镁(Ⅱ)含量在0 ̄480μg/L范围内呈良好线性关系,检测限为3.7μg/L,据此建立测定痕量镁的新方法,并应用于矿样及血清中痕量镁(Ⅱ)的测定,结果满意。 相似文献
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以(+)-4,10-二氧杂三环[5.2.1.O^2,6]-癸-8-烯-3-醇为原料。经8步反应,对映选择性地合成出去氧维生素H的重要中间体:(2S,3S,4R)-2-正戊基-3,4-二叠氮基四氢噻吩。为对映选择性合成手性四氢噻吩类化合物提供了新的方法。 相似文献
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新试剂2—(8‘—羟基喹啉—5’—磺酸—7‘—偶氮)—变色酸二阶导数光… 总被引:1,自引:0,他引:1
以新试剂2-(8’-羟基喹啉-5’-磺酸-7’-偶氮)-变色酸(简称8Q5SAC)作为显色剂,在硼砂-氢氧化钠缓冲体系中,用二阶导数吸光光度法测定微量镁,镁在0~15μg/25ml中符合比耳定律,可不经分离直接测定水样中镁,结果满意。 相似文献
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头发微量元素及钙含量测定的应用价值评价 总被引:5,自引:1,他引:5
熊丽萍 《广东微量元素科学》2003,10(8):49-52
以125例2~5岁儿童为对象,测定其全血和头发铅、锌、铁、钙含量;以全血铅、锌、铁、钙含量为标准,应用诊断试验评价方法评价头发铅、锌、铁、钙测定的应用价值。结果表明,头发铅测定的灵敏度可达88.3%,应用串联试验,头发铅测定的特异度可提高至81.8%,阳性预测值达69.6%,阴性预测值达78.8%。头发锌测定的灵敏度可达86.1%,特异度为52.4%,阳性预测值75.6%,阴性预测值为68.8%。头发铁测定的灵敏度为72.0%,特异度为77.5%,阳性预测值为83.6%,阴性预测值为63.3%,头发钙测定的灵敏度为78.9%,特异度为69.1%,阳性预测值为69.8%,阴性预测值为78.4%。锌缺乏、铁缺乏、钙缺乏,或铅负荷过高,或数种微量元素缺乏及铅中毒并存是当前严重影响儿童健康成长的常见原因。运用现代检测技术早期发现微量元素缺乏及铅中毒患儿并及时采取防治措施对促进儿童正常生长发育至关重要。头发样品容易采集、运送和保存,因此头发微量元素含量测定适合在中小城镇及农村使用。但其应用价值应进行科学评价。 相似文献
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建立了亲水相互作用色谱柱(HILIC)串联C18柱的方法,高效分离实际样品中的胭脂红,并对色谱柱的串联顺序以及色谱分离条件进行优化。结果表明:当HILIC柱在前C18柱在后,流动相为乙腈-乙酸铵(5 mmol/L)=91∶9(V/V),流速为0.9 mL/min,柱温为25℃,检测波长为508 nm时,此时胭脂红的分离效果最佳。在最佳的色谱分离条件下,选用两种市售饮品进行实际样品的测定,回收率在81.2%~119%。方法适用于水相样品中的强极性物质的高效分离与分析。 相似文献
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提出了用气相色谱-质谱法测定纺织品中N-乙基全氟辛烷磺酰胺的方法。试样经甲醇超声提取后,在旋转蒸发仪中浓缩至5 mL,通过DB-5MS色谱柱分离,采用选择离子监测模式检测,定性离子为m/z69,108,131,169,448,定量离子为m/z108。N-乙基全氟辛烷磺酰胺的质量浓度在0.2~20.0 mg.L-1范围内与峰面积呈线性关系,检出限(3S/N)为0.69μg.L-1。用标准加入法做回收试验,测定平均回收率为97%。 相似文献
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An application of polyacrylamide-grafted-gum ghatti (PAAm-g-GGH) copolymer for transdermal delivery of an anti-psychotic drug, quetiapine fumerate triggered by electric stimulus was explored. The electro-responsive PAAm-g-GGH was prepared by free radical polymerization underneath nitrogen atmosphere subsequent to alkaline hydrolysis. The PAAm-g-GGH was used as drug reservoir gel and crosslinked films of GGH and PVA as rate controlling membranes (RCM). The reservoir gels were uniform and translucent; pH of gels was 6.56–7.06, which is in the pH range of skin and drug content was from 89.57% to 94.51%. The thickness of RCMs was 163–227?μ; thickness was increased with increased glutaraldehyde concentration and all the RCMs were permeable to water vapors. When electric stimulus was absent, a small amount of drug was permeated from the formulations, while drug conveyance was enhanced in the existence of stimulus. Drug permeation was increased with increase in electric stimulus from 2 to 8?mA. Over two fold increase in flux was observed after application of electric stimulus. Under “on–off” electric stimulus, faster drug permeation was seen under ‘on’ condition and permeation was decreased when stimulus was ‘off.’ Histopathology study confirmed reversible alteration of skin structure under electric stimulus. 相似文献
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A rapid, sensitive and selective high performance liquid chromatography (HPLC) method was developed and validated for determination of loganin in rat tissues. Samples were prepared based on a simple protein precipitation. Separation of loganin was achieved on a reversed-phase C(18) column (250 x 4.6 mm, 5 microm) with a mobile phase consisting of acetonitrile and water (16:84, v/v) at a flow rate of 1.0 mL/min. The detection wavelength was set at 236 nm and the temperature of the column was kept at 30 degrees C. The method was applied to study tissue distribution of loganin in rats after a single administration of loganin at a dose of 20 mg/kg. The highest level was observed in kidney, then in stomach, lung and small intestine. The lowest level was found in brain. The peak levels were attained at 90 min in most tissues. It was indicated that kidney was the major distribution tissue of loganin in rats, and that loganin had difficulty in crossing the blood-brain barrier. It was also found there was no long-term accumulation of loganin in rat tissues. 相似文献
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建立了动态超声辅助萃取与高效液相色谱在线联用系统,用于测量淫羊藿中黄酮类化合物。萃取过程在一个循环体系中完成,萃取完成后,通过采样环采集20μL萃取液,萃取液被流动相载入色谱系统进行分离检测。4种黄酮类化合物用HPLC–MS区分,通过比较色谱峰面积选择优化萃取条件。选择50℃的水浴温度,50%的乙醇作为萃取剂,萃取剂流速为1.5 mL/min,萃取时间为8 min,样品量为15 mg。用该法测量淫羊藿样品中4种黄酮类化合物,日内、日间精密度分别为1.05%~2.05%,0.30%~3.63%(n=6)。淫羊藿中的主要化合物淫羊藿苷的加标回收率为95.2%。该方法可用于测量淫羊藿中的黄酮类化合物。 相似文献
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顶空气相法测定氯乙烯生产过程产生的盐酸溶液中的乙炔和氯乙烯 总被引:3,自引:0,他引:3
采用顶空气相法测定了氯乙烯生产过程产生的盐酸溶液中的乙炔和氯乙烯。使用氢氧化钠将试样中的氯化氢中和 ,从而消除其在气相分析乙炔和氯乙烯中的影响。顶空平衡温度为 35℃ ,平衡时间为 4 5min ,柱为填充了GDX 2 0 2固定相的 2m× 3mmi d 不锈钢柱 ,柱温 14 0℃。顶空气体进样量为 1mL。以外标法定量 ,乙炔含量测定结果的相对标准偏差为 0 85 % ;当其含量为 30 0 μg/g~ 15 0 μg/g时 ,回收率为 98 9%~10 3%。氯乙烯含量测定结果的相对标准偏差为 1 4 % ;当其含量为 2 0 0 μg/g~ 10 0 μg/g时 ,回收率为 98 8%~10 2 %。 相似文献