共查询到20条相似文献,搜索用时 93 毫秒
1.
本文建立了一种用离子色谱-电导检测器测定配制酒中甜蜜素、安赛蜜、糖精钠、山梨酸、苯甲酸、硝酸根、硫酸根和氯离子的方法.以IonPac AS1 7-C色谱柱为分离柱,用KOH梯度洗脱方式使待测组分分离,流速为1 mL/min,抑制电导检测.该方法线性范围0.1~50 mg/L,方法回收率在94.0%到104.1%之间,适合于配制酒中甜味剂、防腐剂和常见无机阴离子的检测. 相似文献
2.
3.
4.
5.
高效液相色谱法测定对虾中五种磺胺类药物残留 总被引:5,自引:1,他引:5
采用反相高效液相色谱法,同时测定对虾中的五种磺胺类药物残留。用C18柱.紫外(或PDA)检测器,流动相为5mmol/L NaH2PO4溶液.乙腈溶液,磷酸调pH2.8,流速1.0mL/min,枉温35℃,于267nm波长处检测。最低检测限达到2μg/kg,相关系数在0.9997以上。五种药残加标回收率在100μg/kg,50μg/kg,10μg/kg三个水平上分别为81.90%,79.86%,71.80%,RSD<10%亦符合痕量测定要求。 相似文献
6.
《分析仪器》2020,(3)
目的研究建立高效液相色谱法检测含乳饮料中的苯甲酸、山梨酸和糖精钠3种添加剂含量的分析方法。方法样品经亚铁氰化钾和乙酸锌沉淀蛋白,0.45μm滤膜过滤;采用shimadzu ODS-C_(18)色谱柱分离,梯度洗脱,PDA检测器检测,外标法定量分析。结果 3种添加剂苯甲酸、山梨酸和糖精钠在浓度0.3~12μg/mL范围内,具有良好的线性关系,相关系数R~2均大于0.999;检出限在0.05~0.10mg/kg之间;加标回收率在92.26%~100.82%之间;重复性RSD在5.0%以内。结论该方法具有简便、重复性好、速度快等特点,适用于含乳饮料中防腐剂和甜味剂的测定。 相似文献
7.
本文采用标准系列钴酸锂基体匹配,用1+1盐酸溶解,在1%的盐酸介质中,用火焰原子吸收法,测定了钴酸锂中钾、钠、钙、镁、铜、铅、锌、铁、锰、镍等微量杂质含量。通过试验,确定了溶剂和介质的用量;对释放剂SrCl,的加入量进行了实验,选择了最佳加入量;对溶剂和样品中的共存元素进行了干扰实验。各元素的检出限分别为:钾:0.005μg/mL,钠:0.004μg/mL,钙:0.009μg/mL,镁:0.005μg/mL,铜:0.005μg/mL,铅:0.019μg/mL,锌:0.009μg/mL,铁:0.0151μg/mL,锰:0.005μg/mL,镍:0.012μg/mL,样品加标回收率在98—104%之间,相对标准偏差(RSD)为:0.96-9%,方法简便、快捷,仪器低廉,易于普及,适于钴酸锂中的微量元素检测。 相似文献
8.
反相离子对色谱柱后衍生法测定生物组织中四种生物胺的含量 总被引:1,自引:0,他引:1
采用反相色谱柱后衍生法测定肌肉组织中的酪胺、亚精胺、腐胺和尸胺含量。样品经0.6mol/L的高氯酸溶液匀浆提取;流动相为10mmol/L的辛烷磺酸钠溶液(pH5.2)与0.1mol/L乙酸钠溶液一乙腈(pH4.5),流速1mL/min;柱后衍生液为0.1%邻苯二甲醛(OPA)溶液(pH10.5~11.0),流速0.5mL/min;Discovery C18分离柱和保护柱;荧光检测器的激发波长和发射波长分别为340nm和450nm;采用62rain的梯度洗脱程序;外标法定量测定。该方法在0.2~10μg/mL的浓度范围内具有良好的线性关系,酪胺、亚精胺、腐胺、尸胺的方法回收率在85.2%~103.3%之间,最低检测限为0.2μg/mL。 相似文献
9.
10.
GC-MS法测定尿中γ-羟基丁酸 总被引:1,自引:0,他引:1
γ-羟基丁酸(GHB)是娱乐场所滥用的麻醉药。本文用气相色谱-质谱法(GC-MS)测定尿中GHB。尿样酸化后于80℃经20min GHB转化为丁内酯(GBL),用二氯甲烷提取,气相色谱-质谱-选择离子检测模式测定,正己酸为内标。检测离子(GBL为m/z86、56、42、28,内标为m/z87、73、60、41,定量离分别为m/z86和87。方法检出限0.08μg/mL(S/N=3)。尿中加标10μg/mL,6次测定的相对标准偏差为2.5%,回收率57.7%。线性范围0~50μg/mL,相关系数(r^2)为0.9996。用该方法分析20个尿样,GHB浓度都低于1μg/mL。该方法灵敏度高,简单可靠,适用于法医和临床检验。 相似文献
11.
12.
建立了用抗坏血酸为还原剂的分光光度法测定工作场所空气中磷酸的方法。微孔滤膜采集空气中的磷酸雾,水洗脱后,在酸性溶液中,与钼酸铵生成磷钼杂多酸,以抗坏血酸还原,生成磷钼蓝,在700nm波长下用分光光度计测定。方法曲线的相关系数r=0.9999,线性范围0~200μg,检出限0.068μg/mL,相对标准偏差为0.17%~0.96%,加标回收率为94.0%~103.9%。用本方法测定工作场所空气中磷酸,效果很好、线性关系良好、检出限低、准确度及精密度高。 相似文献
13.
Ethyl hexyl esters of oleic, linoleic, and linolenic acids were synthesised and thermally polymerised to obtain products with viscosities in the range of hydrocarbon lubricants at 100°C (11–22 cSt). Molecular weight, elemental analysis, IR, 13C NMR, and intrinsic viscosity data showed that most of these derivatives are mixtures of monomers, dimers, and trimers and have linear and cyclic products with predominantly trans characteristics. The lubricity characteristics were determined on a friction and wear tester under conditions of thick‐film lubrication. A comparison was made with hydrocracked hydrocarbon lubricants of comparable viscosities at 100°C and comparable viscosity indices. It is inferred that all the esters maintained relatively thicker surface films and much lower friction coefficients than the hydrocarbon oils. The wear‐scar data show that the antiwear characteristics of polymerised ethyl hexyl oleate and linoleate are only slightly inferior to those of the hydrocarbon oils, but at higher temperatures their antiwear characteristics rapidly deteriorate while the friction coefficients markedly increase and become comparable to those of hydrocarbon oils. These studies are being undertaken with a view to selecting and modifying vegetable oils containing mixtures of fatty acids for obtaining esters of outstanding friction, wear, and film‐forming characteristics. 相似文献
14.
目的建立食品中山梨酸、苯甲酸检测方法并对其前处理进行合理的改良。方法样品经盐酸酸化,用乙醚提取,接着用氯化钠酸性溶液洗涤2次后将提取液转入无水硫酸钠溶液中蒸发近干,残渣用丙酮溶解;用色谱柱分离,具氢火焰离子化检测器进行检测。结果本法山梨酸和苯甲酸相对偏差分别为3.71%和2.11%;加标回收率分别为87.0%-95.2%和97.0%-103.1%,远远高于国标法中的回收率。结论本方法样品前处理操作简单方便,准确度和灵敏度高,适用于食品中山梨酸、苯甲酸的测定。 相似文献
15.
Evaluation of smear layer removal and marginal adaptation of root canal sealer after final irrigation using ethylenediaminetetraacetic,peracetic, and etidronic acids with different concentrations 下载免费PDF全文
The purpose of this study was to investigate the effects of different irrigation solutions on the smear layer removal and marginal adaptation of a resin‐based sealer to root canal dentine. A total of 152 instrumented roots were irrigated with the following irrigants: 9,18% etidronic acid (HEBP), 0.5, 1,2% peracetic acid (PAA), 17% ethylenediaminetetraacetic acid (EDTA), saline. The amount of smear layer was evaluated using scanning electron microscope (SEM) in seventy root samples. Eighty‐two roots were filled with AH Plus and gutta‐percha. Slices obtained from apical third of each specimen were viewed with SEM to assess marginal adaptation. Use of 9% and 18% HEBP resulted in more efficient smear layer removal in the apical third than the other chelators (p < 0.05). Higher smear layer scores in the coronal and middle thirds were obtained from 0.5%, 1% PAA groups. Regarding marginal adaptation, 18% HEBP group showed the lowest gap size values (p < 0.05), and better marginal adaptation. Etidronic acid is a promising candidate for final irrigation of root canals. 相似文献
16.
17.
18.
19.
20.
HPLC法测定熊去氧胆酸含量 总被引:1,自引:0,他引:1
应用高效液相色谱法对熊去氧胆酸原料药进行含量测定。色谱柱为HypersilODS25μm,250mm×4.6mm,流速为1.0mL/m in;检测器为UV205nm。该实验有助于对熊去氧胆酸含量测定方法的确定。 相似文献