高效液相色谱-串联质谱法检测中药材中有机磷农药残留量

研究了中药材中有机磷农药残留量的高效液相色谱-串联质谱同步检测方法.采用CAPCELL PAK MC C18反相柱,以乙腈为提取溶液,以Carb/PSA柱为净化柱,液相色谱-串联质谱仪测定.方法线性范围为10～500 μg/L,11种有机磷农药在此范围内线性良好,相关系数为0.9961～0.9999.在10～100 μg/kg浓度范围内,加标回收率在70%～110%之间,相对标准偏差为1.4%～11%,最低检出限为2～20μg/kg,符合残留检测分析要求.     

双层石墨烯位于1800—2150cm~(-1)频率范围内的和频拉曼模

文章利用拉曼光谱研究了双层石墨烯在1800—2150 cm-1范围内的和频拉曼模.基于双共振拉曼散射理论,利用多波长激光拉曼散射结合声子色散曲线分别从实验上和理论上分析发现,双层石墨烯在此频率范围内主要存在4个拉曼模,它们主要由LO和LA或iTA按不同共振散射方式所组成的4个和频模,而iTO和oTO参与和频的可能性很小.文章澄清了学术界在1800—2150 cm-1频率范围内和频模的解释,有助于进一步深入理解多层石墨烯在此范围内的和频模.     

ICP-OES法测定内蒙古饮茶型氟中毒病区人发、人尿中多种生命元素

应用等离子体发射光谱仪(ICP-OES)法测定了内蒙古饮茶型氟中毒病区锡林浩特市有长期饮砖茶习惯的蒙古族牧民以及对照组(不饮砖茶的汉族居民)的发和尿中Ca,Mg,K,Al,P,Cu,Zn,Fe等八种生命元素的含量.标准物质测定结果满意,方法精密度介于2.32%到8.03%之间.通过人发和人尿样品的测定,发现长期饮砖茶人群的发铝、发镁、发钾明显高于对照组(P<0.05),尿铝、尿钙也显著高于对照组,而尿钾低于对照组(P<0.05).表明长期饮用砖茶会影响体内Al和Ca等生命元素的代谢,其机理需进一步深入研究.     

Study on the interference elimination of trace cadmium in superalloy by ICP-MS / MSEI北大核心CSCD

A triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS / MS) method was developed for the determination of trace Cd in superalloys. Meanwhile, the interference elimination effects of different collision / reaction gases (He, O2 and NH3) in single quadrupole mode (SQ) and double quadrupole mode (QQQ) were investigated. The results indicated that the modes of QQQ-O2 and QQQ-NH3 possessed satisfactory interference elimination effect than the others. The optimal flow rates of O2 and NH3 were 0. 75 mL / min and 0. 50 mL / min, respectively. In order to verify the interference elimination effect, the recovery rate of 0. 1 μg / g Cd in 0. 10 mg / g to 100 mg / g Mo content solutions, as well as the determination results of superalloy standard substance and the actual sample were investigated. The measured value was within the range of the standard value, and the measured value of the actual sample was consistent with that of the hydride generation atomic fluorescence method. Therefore, the proposed method can eliminate the polyatomic ions interference of Mo on trace Cd. © 2022, Youke Publishing Co.,Ltd. All rights reserved.     

高效液相色谱串联质谱法对栀子中11种有机磷农药残留的检测

建立了高效液相色谱串联质谱法检测栀子中11种有机磷农药残留量的分析方法。样品以乙腈为提取溶剂,采用超声波辅助提取,经Carb/PSA固相萃取柱净化,液质联用仪测定。11种有机磷农药在125~2 000μg/L范围内线性良好,相关系数为0.9955~0.9998。在50、100、500μg/kg 3个添加水平的平均加标回收率为84%~107%,相对标准偏差为1.4%~10.9%。