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碘的凝胶色谱测定方法 总被引:6,自引:1,他引:6
建立了碘折凝胶色谱测定方法。色谱条件为:Shim-pack DIOL-150柱;流动相甲醇0.01mol/L H3PO4(10:90)流速为1.2mL/min;柱温为35℃,检测波长为224nm;线性范围是0.010-1.0mg/L,相关系数为0.9993,检测限为0.001mg/L,相对标准偏差为1.2%-4.6%;回收率为91%-98%。所建立的方法已用于食盐,尿,系带等样品的测试,均取得较好 相似文献
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本文研究了在Cl ̄-和I ̄-的混合物中,加入过量Ag ̄+使Cl ̄-和I ̄-分别以AgCl和AgI沉淀后,用ICP-AES测定剩余的Ag ̄+,然后用NH_3·H_2O溶解AgCl沉淀,测定溶解液中的Ag ̄+,间接得到Cl ̄-的含量,以差减法求得I ̄-量,实现Cl ̄-和I ̄-的间接法连续测定。本文探讨了有关的化学条件和光谱测定条件,对方法的适用性进行了考察──共存离子的干扰情况,方法的精密度、检出限和试样中加入回收试验。回收率为97.1%~101.2%(Cl ̄-),98.1%~100.4%(I ̄-)。 相似文献
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萃取火焰原子吸收法测定食品中铅 总被引:6,自引:2,他引:4
采用干经处理样品,APDC-MIBK萃取,同时考察了萃取条件对测定的影响,结果令人满意。铅的平均回收率为98.7%,相对标准偏差为4.4%。 相似文献
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1引言 经典莫尔法对于 0.01 mol/L的Cl-滴定误差达十0.6%需要进行指示剂的空白校正.且因 Agl、AgSCN沉淀强烈吸附I-和SCN-、Ag2CrO4。沉淀凝聚后再转化成AgCl极慢,故不适于直接滴定I-、SCN-、Ag-。作者以聚丙烯酰胺(PAM)化学修饰AgX(x-=I-、SCN-、Br-、Cl-)及Ag2CrO4沉淀的结构,减小Agx对X-的吸附与促进Ag2CrO4的转化,用莫尔法直接测定I-、SCN-、Ag+及不需空白校正能准确滴定 0.01 mol/LCl-未见报道… 相似文献
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用铬天青S-溴化十六烷基吡啶胶束增溶分光光度法测定头发中的铝 总被引:1,自引:0,他引:1
讨论了用CAS-CPB胶束增溶比色法测定头发中铝含量的最佳实验条件。最大吸收波长为630nm,铝的线性范围为0~4.0μg,变异系数CV=3.2%(n=6),回收率为98%。 相似文献
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贵金属同时浮选分离富集行为的研究及ICP-AES的测定 总被引:3,自引:0,他引:3
本文通过对贵金属-碘化钾-孔雀绿显色体系的浮选行为研究,建立了一种同时浮选富集分离铂、钯、铑、铱、金的新方法。实验结果表明,在0.36mol/LHCl0.1mol/LKI和2.4×10 ̄(-4)mol/LMG的溶液中,加入环已烷振荡1min,铂、钯、铑、铱、金可被定量浮选,继而用ICP-AES测定。对含量为5~150μg的贵金属,浮选回收率分别为铂88.6%~95.7%,钯92.3%~99.5%,铑93.7%~101%,铱92%~98.5%,金86.4%~94%。方法应用于铜镍矿、铂网废料等物料中上述贵金属元素的测定,结果满意。 相似文献
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反相高效液相色谱法测定氟离子 总被引:8,自引:0,他引:8
1引言本文建立了反相液相色谱测定氟离子的方法,与分光光度法相比,可将含氟络合物与试剂分离开,大大提高了测定的灵敏度和选择性。测定条件为Shim-PackCLC-ODS(6×150mm5u);流动相:甲醇-水(18:82);流速:1mL/min;柱温:35℃;检测波长:566nm。线性范围0.050~1.0mg/L;相关系数r=0.9991;检测限为0.001mg/L;相对标准偏差为1.9%~2.7%;回收率为97%~98%。本方法初步用于矿泉水和食盐等样品的测定,均取得较好的效果。2实验部分2.… 相似文献
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麻疯油转酯化产物的高效液相色谱分析 总被引:2,自引:0,他引:2
建立了高效液相色谱法同时测定麻疯油转酯化产物中4种主要脂肪酸甲酯的分析方法。样品经膜处理后用丙酮溶解,采用Hypersil ODS(C18)色谱柱进行分离。以乙腈为流动相进行等度洗脱,内标法定量,同时对色谱条件进行优化。结果表明,在优化的色谱条件下4种脂肪酸甲酯在10 min内得到良好的分离,标准曲线的线性相关系数均达到0.999以上,平均回收率为96%~98%,重现性相对标准偏差为7.2%~10.2%,重复性相对标准偏差为0.31%~2.02%。与气相色谱法相比,该方法具有较高的灵敏度,可用于麻疯油转酯化产物中脂肪酸甲酯含量的测定,为麻疯油转酯化反应制备生物柴油的定性定量分析提供了参考依据。 相似文献
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Silvia Dulanská Boris Remenec Ján Bilohuštin Miroslav Labaška Dušan Galanda 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):2189-2192
This paper describes the use of IBC’s AnaLig® Sr-01 molecular recognition technology product to effectively and selectively pre-concentrate, separate, and recover strontium from urine samples. This method uses two-stage columns separation consisting of two different commercial products Eichrom’s Pre-filter Material and AnaLig® Sr-01 column from IBC Advanced Technologies. This method does not involve co-precipitation of strontium as phosphates and oxalates from urine samples. The new rapid method separates strontium-90 with high chemical recovery. 相似文献
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Determination of plant growth regulators in pears by microwave‐assisted extraction and liquid chromatography with electrospray ionization mass spectrometry 下载免费PDF全文
A new method for the determination of six plant growth regulators, 3‐indolylacetic acid, 3‐indolepropionic acid, 2‐naphthoxyacetic acid, 2,4‐dicholrophenoxyacetic acid, 1‐naphthlcetic acid, and methyl naphthalene‐1‐acetate, in pears was established by liquid chromatography with electrospray ionization mass spectrometry. In this study, a microwave‐assisted extraction technique was first applied for the determination of plant growth regulators in fruit and three cleanup techniques were, respectively, investigated for the purification of pear samples. The chromatographic separation was performed on a Diamonsil C18 column by using 0.01 mol/L formic acid/ammonium formate buffer solution (pH 3.5)/methanol (35:65, v/v) as the mobile phase with a flow rate of 0.7 mL/min in 1:1 split mode. The LODs ranged from 0.3 to 1.9 μg/kg. Under optimized conditions, the average recoveries (five replicates) for six plant growth regulators (spiked at 0.01, 0.05, and 0.5 mg/kg) ranged from 78.9 to 118.0%, and the RSDs were 1.4–10.3%. 相似文献
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Silvia Dulansk�� Boris Remenec ?ubom��r M��tel Du?an Galanda Atilla Moln��r 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(3):705-708
This paper describes the use of IBC??s AnaLig®Sr-01 molecular recognition technology product to effectively and selectively pre-concentrate, separate and recover strontium from radioactive waste samples. The use and effectiveness of AnaLig®Sr-01 gel was successfully validated by analysis of International Atomic Energy Agency (IAEA 375) reference soil and National Physical Laboratory (NPL)?CHigh Alpha?CBeta (2003) liquid sample. The second part of this paper focuses on analysis of radioactive waste samples from nuclear power plant A1 Jaslovske Bohunice in Slovak Republic (NPP A1). 相似文献
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NP-HPLC分离氨氯地平对映体及其含量测定 总被引:1,自引:0,他引:1
建立直接拆分氨氯地平对映体的HPLC方法,并用于其含量测定.以CHIRALPAK AD-H为固定相,在正相条件下考察了流动相组成、流速、柱温等因素对氨氯地平对映体分离度的影响.在优化条件下,分别测定了氨氯地平对映体的含量.实验表明,以正己烷-乙醇-二乙胺(95 : 5 : 0.1,体积比)为流动相,流速 1.0 Ml/min,检测波长 360 nm,柱温 30 ℃,氨氯地平对映体的质量浓度均在0.01 ~0.06 g/L范围内线性关系良好(Rr=0.998 3,Rs=0.998 7).高、中、低3个浓度平均回收率(n=3)分别为99%、101%、101%,相对标准偏差依次为0.76%、0.68%、0.98%.该分析方法准确可靠、快速、简单、重复性好,可用于左旋氨氯地平工业化制备中动态拆分过程的跟踪分析及产品质量控制. 含量.实验表明,以正己烷-乙醇-二乙胺(95 : 5 : 0.1,体积比)为流动相,流速 1.0 Ml/min,检测波长 360 nm,柱温 30 ℃,氨氯地平对映体的质量浓度均在0.01 ~0.06 g/L范围内线性关系良好(r_R=0.998 3,r_S=0.998 7).高、中、低3个浓度平均 收率(n=3)分别为99%、101%、101%,相对标准偏差依次为0.76%、0.68%、0.98%.该分析方法准确可靠、快速、简单、重复性好, 相似文献
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以苯甲酸甲酯为促进剂,用茂金属催化剂制备了活性丁苯嵌段共聚物(SBS)的选择性催化加氢产物,讨论了苯甲酸甲酯、SBS的数均分子量等因素在几种实验条件下对产物加氢度的影响.结果表明,每百克干胶使用0.15~0.3mmol Ti催化条件下,苯甲酸甲酯在特定添加方式下能较大程度地提高茂金属催化剂的活性.在不加入苯甲酸甲酯的情况下,Mn=6.5×104和Mn=5.5×104两种SBS基础胶加氢反应180min时加氢度均97.0%;加入酯以后,反应60~120min时,基础胶的加氢度≥98%;与已报道的研究结果相比,将加氢反应时间缩短了60~120min.在每百克干胶使用0.15~0.3mmolTi催化条件下,数均分子量的大小也对SBS基础胶的加氢度有影响,反应30min时,Mn=5.5×104的加氢度≥97%,Mn=6.5×104的加氢度90%;随着反应时间的延长,这种差距在逐渐缩小;反应180min时,两者已无明显差距,此时两种基础胶的加氢度都≥98%.对影响的加氢度的机理进行了解释. 相似文献
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Summary A simple and efficient method is described for the determination of fenpropathrin in oranges, pears, apples and strawberries.
The procedure is based on the extraction of each homogenized fruit sample with hexane:acetone (1∶1, v/v) mixture, followed
by a cleanup technique on a column packed with florisil, using a hexane:ethyl ether (7∶3, v/v) mixture, and gas chromatographic
analysis with electron capture detection (ECD). The fortification levels (0.5;1.0;2.0 mg kg−1) were selected according to the maximum residue limits (MRLs) established for fenpropathrin by Brazilian legislation. Mean
recoveries from five replicates of fortified fruit samples ranged from 83 % to 98%, with coefficients of variation from 1.4
to 13.5 and detection limits varying from 0.1 to 0.2 mg kg−1. 相似文献
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建立了用紫外检测的反相离子对色谱梯度淋洗同时分离测定4种吡啶离子液体阳离子和5种咪唑离子液体阳离子的方法。实验采用ZORBAX Eclipse XDB-C18反相色谱柱,以离子对试剂水溶液(用柠檬酸调节pH值)+乙腈为流动相,考察了离子对试剂种类和浓度、乙腈浓度和色谱柱温度对保留的影响,探讨了相关保留规律,确定最佳色谱条件为:流速1.0 mL/min、柱温30℃,以1.0 mmol/L庚烷磺酸钠水溶液(pH 4.0)-乙腈为淋洗液进行梯度洗脱。在此条件下,4种吡啶阳离子和5种咪唑阳离子在15 min内达到基线分离。检出限(S/N=3)为0.31~0.54 mg/L,峰面积的相对标准偏差为0.10%~0.75%。将该方法用于实验室合成的离子液体样品分析,加标回收率为94%~98%。该方法准确、可靠,具有较好的实用性。 相似文献
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A gas-liquid chromatographic method developed for the determination of putrescine and cadaverine in fishery products was modified for application to the determination of diamines in shrimp. Addition of potassium chloride and hydrochloric acid to the methanol-water extraction solvent resulted in increased recovery of the diamines and minimized gel formation. The recovery of putrescine increased on average from 64 to 98%, and the recovery of cadaverine increased from 85 to 93%. The chromatographic separation of the derivatized diamines was significantly improved with a change from an OV-225 column (cyanopropyl methyl phenyl methyl silicone) to a more polar HP-Innowax column (crosslinked polyethylene glycol). Background levels of putrescine and cadaverine in known high-quality shrimp ranged from 0 to 0.7 ppm. Shrimp that failed sensory examination generally contained putrescine at levels >4.8 ppm and cadaverine at levels >1.3 ppm. 相似文献