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在酒后驾车引发的交通肇事案中,对驾驶员进行酒精的定性和定量检验对事故责任的定性有至关重要的作用。对气相色谱法测定酒后人体汗液中乙醇含量的方法进行了研究与探讨。通过对酒后人体分泌的汗液进行实验.利用乙醇易挥发的性质,用火焰离子(FID)检测器,采用顶空-气相色谱法进行分析测定,以峰面积定量,利用两点法测定汗液中的乙醇含量。此方法具有操作简便,快速,测定结果准确等特点。 相似文献
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本文叙述了在10.2M硫酸酸性介质中,以重铬酸钾为氧化剂与酒精废水中的乙醇反应,剩余的重铬酸钾用电解产生的亚铁离子作为库仑滴定剂,进行恒电流库仑滴定,根据电解产生的亚铁离子消耗的电量,按照法拉弟定律,换算为乙醇含量,本法快速、准确、回收率为97%~100.11%。该法对酒精废水中乙醇浓度的测定是较理想的方法。 相似文献
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探讨了以谷物为原料液态法生产酒精时,醪液中的糖、有机酸和乙醇的HPLC分析方法。该方法在发酵酒精生产中的运用和推广,解决了长期以来因化学方法测定醪液既费时又无法同时确定残糖、有机酸及乙醇的准确含量问题,为快速指导生产控制提供了有效途径。 相似文献
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气相色谱法测定甲醇和乙醇 总被引:2,自引:0,他引:2
建立了气相色谱法检测甲醇和乙醇含量的方法。采用微量注射器定量进样,填充柱分离,氢火焰离子检测器检测。以甲醇、乙醇水溶液为标样,峰面积--外标法定量。此方法可用于甲醇中乙醇含量的分析或乙醇中甲醇含量的分析。分析浓度范围从微量到常量。该方法用于甲醇中乙醇及水溶液中甲醇、乙醇的测定,其结果较满意。 相似文献
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以苦瓜为原料,建立了SPE精制、HPLC检测、ESI-MS定性为主要步骤的苦瓜皂苷的分析方法。通过HPLC测定,得到了SPE精制的最佳工艺条件为:上样pH为8,经10%、20%乙醇各15mL淋洗后用10mL40%乙醇淋洗,洗脱液为65%乙醇,洗脱体积为7mL,流速为1mL/min,此条件下所得液相色谱的峰数、峰形、峰面积均较理想。测得最佳条件下精制的苦瓜总皂苷含量为82.13%。经ESI-MS定性分析得出,精制后的产物为三萜类皂苷。苦瓜皂苷快速分离方法的研究,对其构效关系和生物活性研究提供了重要的前提条件。 相似文献
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基于3,5-Cl2-DMPAP在乙醇等溶剂中主要呈黄色或橙黄色,而在甲醇介质中呈紫红色,最大吸收峰红移100 nm左右,试剂对甲醇有独特的识别作用,建立了用二个波长测定吸光度计算甲醇汽油中甲醇含量的新体系,研究了测定条件的影响。方法简单、快速、选择性好,结果令人满意。 相似文献
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《应用化工》2022,(5):990-993
建立了高效液相色谱法测定酒类饮品中总乙醛含量的分析方法。样品经氢氧化钠提取后,用碘甲烷对乙醇进行甲基化,2,4-二硝基苯肼(DNPH)进行衍生,并用正己烷萃取,反相色谱柱进行分离,二极管阵列检测器进行检测。在给定的浓度范围内,乙醛浓度与峰面积具有良好的线性关系,相关系数(r)为0.999 3。添加水平在40150 mg/L时回收率为83.2%150 mg/L时回收率为83.2%95.5%,相对标准偏差RSD(n=6)为5.74%95.5%,相对标准偏差RSD(n=6)为5.74%8.42%,方法检测限为0.6 mg/L。该方法操作简便、准确度高、重现性好,是测定葡萄酒中总乙醛含量的有效方法。 相似文献
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建立了头孢唑肟钠原料药中有机溶剂残留量的测定方法。采用顶空进样毛细管气相色谱法,DB-624(30 m×0.53 mm×1.5μm)毛细管柱分离,以氮气为载气,FID检测器测定甲醇、乙醇、异丙醇、二氯甲烷、乙酸甲酯等溶剂残留量。结果表明,5种有机溶剂完全分离,质量浓度在考察范围内与峰面积具有良好的线性关系(r〉0.99),平均回收率为92.0%~105.6%,精密度RSD均〈10%,最低检出限为0.03-0.06μg·mL^-1。顶空气相色谱法快速、灵敏、准确,可用于头孢唑肟钠5种有机溶剂残留量的测定。 相似文献
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紫外分光光度法测定山楂中的总黄酮含量 总被引:1,自引:0,他引:1
在0.008-0.040mg/mL线性范围内,建立以硝酸铝-亚硝酸钠为显色剂,紫外分光光度法测定山楂总黄酮含量方法。结果表明,该法简便易行、快速、准确。并对山楂总黄酮的乙醇提取工艺进行了研究,优选出最佳山楂提取工艺为乙醇浓度为60%,回流提取2次,每次1.5-2h。 相似文献
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目的:建立阿昔洛韦中的残留溶剂乙醇、异丙醇、甲苯的分离测定方法。方法:采用Agilent-DB-1石英毛细管气相色谱柱(30mX0.53nunx5.00胁m),载气为氮气,氢火焰离子化检测器,进样口温度为180℃,检测器温度为250℃。柱温采用程序升温:初始温度为40℃。维持0min,以20℃·min^-1叫速率升至80℃,维持12min;流速为5mL·min^-1。以二甲基亚砜为样品溶剂。结果:乙醇、异丙醇、甲苯的检测限分别为0.257,O.216,O.074μg·mL^-1;定量限分别为1.026,1.020,0.520μg·mL^-1;平均回收率(n=9)分别为100.2%,100.6%,101.2%。结论:本法操作简便,灵敏度高、准确性强;适用于阿昔洛韦中残留溶剂的检测。 相似文献
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A novel ethanol biosensor based on the bulk incorporation of alcohol dehydrogenase (ADH) into a colloidal gold (Aucoll)-multiwalled carbon nanotubes (MWCNTs) composite electrode using Teflon as binding material is reported. The composite Aucoll-MWCNTs-Teflon electrode exhibited significantly improved electrooxidation of NADH when compared with other carbon composite electrodes, including those based on carbon nanotubes. Amperometric measurements for NADH at +0.3 V showed significant differences in sensitivity between Aucoll-MWCNTs-Teflon and MWCNTs-Teflon composite electrodes. Incorporation of ADH into the bulk electrode material allowed the construction of a mediatorless ethanol biosensor. Both the enzyme loading and the NAD+ concentration in solution were optimized. The ADH-Aucoll-MWCNTs-Teflon biosensor allowed a limit of detection for ethanol of 4.7 μmol l−1, which is remarkably better than those reported for other CNTs-based ADH biosensors. The apparent Michaelis-Menten constant was 4.95 mmol l−1, which is much lower than that reported by immobilization of ADH onto a gold electrode. Both repeatability of the ethanol amperometric measurements, reproducibility with different biosensors, lifetime and storage ability can be, in general, advantageously compared with other ADH-CNTs biosensors. The biosensor was applied for the rapid determination of ethanol in commercial and certified beer samples. 相似文献
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Titipong Issariyakul Mangesh G. KulkarniAjay K. Dalai Narendra N. Bakhshi 《Fuel Processing Technology》2007
Transesterification of waste fryer grease (WFG) containing 5–6 wt.% free fatty acid (FFA) was carried out with methanol, ethanol, and mixtures of methanol/ethanol maintaining the oil to alcohol molar ratio of 1:6, and initially with KOH as a catalyst. Mixtures of methanol and ethanol were used for transesterification in order to use the better solvent property of ethanol and rapid equilibrium using methanol. Formation of soap by reaction of FFA present in WFG with KOH instigated difficulty in the separation of glycerol from biodiesel ester. To untangle this problem, two-stage (acid and alkali catalyzed) method was used for biodiesel synthesis. More than 90% ester was obtained when two-stage method was used compared to ∼ 50% ester in single stage alkaline catalyst. In the case of mixed alcohol, a relatively smaller amount of ethyl esters was formed along with methyl esters. Acid value, viscosity, and cetane number of all the esters prepared from WFG were within the range of the ASTM standard. Esters obtained from WFG showed good performance as a lubricity additive. 相似文献