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1.
样品用乙酸乙酯提取,提取液过凝胶渗透色谱,溶液浓缩后,再用C18小柱净化,洗脱液吹干后,经七氟丁酸酐衍生,气相色谱-质谱选择离子定量,两组分分离良好。在兔肉、猪肾和鱼肉样品中进行添加试验,添加水平为1~5μg/kg时,回收率为72.7%~113.8%,测定结果的相对标准偏差为3.90%~12.21%(n=10),检测限为1μg/kg。  相似文献   

2.
建立了鱼粉中孔雀石绿及其代谢物隐色孔雀石绿残留量的超高效液相色谱-串联质谱仪(UPLC-MS-MS)测定法。样品经乙腈提取,中性Al2O3固相小柱净化,超高效液相色谱C18柱分离,电喷雾正离子多反应模式(MRM)检测,内标法定量。方法的定量限为1.00μg/kg,线性范围为0.25~20.0μg/L。在1.00~20.0μg/kg的加标量下,孔雀石绿平均回收率范围为85.3%~104.4%,隐色孔雀石绿平均回收率范围为85.7%~101.4%,相对标准偏差均小于15%。方法适用于鱼粉样品中孔雀石绿残留的快速检测。  相似文献   

3.
以本体聚合法制备孔雀石绿(MG)分子印迹聚合物,并以此为填料,制作针对孔雀石绿的分子印迹固相萃取小柱。鱼肉样品经乙腈超声提取,提取液过分子印迹固相萃取小柱,用甲醇-乙酸(9+1)混合液洗脱,洗脱液采用Eclipse Plus C18色谱柱分离,以50mmol·L-1乙酸盐缓冲溶液-乙腈(4+6)混合液为流动相进行洗脱,检测波长为620nm。孔雀石绿的线性范围为1.00~50.0μg·L-1,检出限(3S/N)为0.62μg·kg-1。对空白鱼肉样品进行加标回收试验,回收率在86.6%~95.4%之间,测定值的相对标准偏差(n=5)在3.6%~6.8%之间。  相似文献   

4.
5.0g水产品组织样品,用乙二胺四乙酸二钠的柠檬酸缓冲溶液提取,用正己烷去除脂肪后,经GL-PakPLS-2小柱净化,旋转蒸发器减压蒸干后,用甲醇-水(30+70)溶液溶解,样液用超高压液相色谱分离,电喷雾串联四级杆质谱进行检测,外标法定量。测定4种四环素类药物的线性范围均为5.0~100.0μg.L-1,在5,20,50μg.kg-1的3个添加水平范围内平均回收率为70.6%~93.4%,相对标准偏差(n=6)为6.3%~10.5%,方法测定下限(10S/N)可达5.0μg.kg-1。  相似文献   

5.
猪尿中26种性激素与13种β2-激动剂的同时测定   总被引:2,自引:1,他引:1  
采用GC-MS对猪尿中26种性激素和13种β2-激动剂进行检测.尿样经β-葡糖苷酸酶水解后,用正己烷、MCX小柱和NH2小柱提取和净化性激素,并由七氟丁酸酐进行衍生,β2-激动剂由同支MCX小柱提取和净化,并用BSTFA衍生.性激素和激动剂的检出限均为0.25 ~1.0 μg/kg.性激素的3个添加水平的平均回收率为86% ~108%,相对标准偏差为8.8% ~20.6%;β2-激动剂的3个添加水平的平均回收率为86% ~108%,相对标准偏差为9.6% ~16.1%.方法实现了对极性差异大和酸碱性相反的两类禁用化合物的同时测定,且前处理简便高效.  相似文献   

6.
超声波提取-气相色谱-质谱联用法测定苏丹红Ⅰ残留量   总被引:9,自引:0,他引:9  
研究了苏丹红Ⅰ的气-质联用检测方法。样品中的苏丹红Ⅰ用超声波提取,采用选择离子(SIM)方式,据保留时间和特征离子丰度比对其进行确证。此方法可以在13 min之内定性和定量地快速检测苏丹红Ⅰ残留,通过多次试验验证,添加量为0.01~1.00μg,回收率在82%~97%之间,相对标准偏差小于5%,检出限为6.0×10-4μg/g。  相似文献   

7.
提出了气相色谱法测定鲍鱼不同组织(肌肉、内脏、整贝)中的多氯联苯含量的方法。样品经正己烷超声萃取,硫酸净化后,肌肉样品只需再经过弗罗里硅土固相萃取小柱净化,内脏和整贝则还需经石墨化碳黑固相萃取小柱净化。用DB-5MS毛细管色谱柱分离,电子捕获检测器检测。7种多氯联苯的质量浓度在1.25~100μg·L-1范围内与相应的峰面积呈线性关系,检出限(3S/N)在0.04~0.06μg·kg-1之间。在0.25,2.50,20.0μg·kg-1 3个浓度水平进行加标回收试验,回收率在78.0%~102%之间,测定值的相对标准偏差(n=5)在3.4%~6.9%之间。  相似文献   

8.
卢杰  冯晓梅  隋晓  陈曼华  韩玉谦  薛长湖 《分析化学》2013,41(10):1487-1492
利用亚临界1,1,1,2-四氟乙烷(R134a)萃取技术,建立了鱼肉中6种性激素残留的气相色谱-质谱(GC-MS)分析方法。样品中的药物经过亚临界R134a萃取后,先进行冷冻过滤去脂,然后通过C18和NH2固相萃取小柱净化,最后经七氟丁酸酐衍生后,采用GC-MS进行定性与定量分析。本实验确定了亚临界R134a萃取6种性激素的最佳条件为:萃取压力4 MPa,萃取温度30℃,夹带剂用量6 mL。在此条件下,6种性激素在5~1000μg/L浓度范围内线性关系良好,相关系数均大于0.99;检出限为0.2~1μg/kg(S/N=3)。在3种浓度添加水平(1,5和10μg/kg)下,6种激素的平均回收率为70.5%~103.6%,相对标准偏差(RSD)为2.1%~12.5%。采用本方法进行实际样品检测时,在一份罗非鱼样品中检出己烯雌酚残留,残留量为14.6μg/kg。  相似文献   

9.
建立了以超高效液相色谱串联四极杆质谱(UPLC-MS/MS)检测鸡和鱼类饲料中10种脂溶性染料的方法。样品经过甲醇振荡提取通过固相萃取小柱去除基质干扰。在waters BEH C_(18)柱子上,乙腈和0.2%(V:V)甲酸,10 mmol/L甲酸铵的水为流动相,利用梯度洗脱将各目标化合物分离,采用质谱多反应监测(MRM)模式进行定量检测。染料在两种饲料中检出限(LOD)为1~5μg/kg,定量限(LOQ)为2~10μg/kg,在鱼饲料中,回收率为80.3%~113.2%,相对标准偏差为1.4%~11%,在鸡饲料中回收率为79.6%~115.4%,相对标准偏差为1.6%~15%。  相似文献   

10.
建立了高效液相色谱-串联质谱(HPLC-MS/MS)测定辣椒及辣椒制品中金刚烷胺残留的分析方法。样品采用1%三氯乙酸溶液-甲醇(1∶1)提取,经Oasis-MCX固相萃取小柱净化后用Atlantis T3 C18柱进行分离,以0.1%甲酸水-乙腈(85∶15)作为流动相进行等度洗脱,电喷雾正离子(ESI+)扫描方式下多反应监测(MRM)模式对样品进行检测。实验结果表明,金刚烷胺在1.0~50μg/kg范围内线性关系良好,鲜辣椒样品的定量下限为1.0μg/kg,干辣椒及干辣椒制品为5.0μg/kg。鲜辣椒在1.0,2.0,5.0μg/kg加标水平下的回收率为72.2%~98.2%,相对标准偏差(n=6)为1.2%~4.6%;干辣椒及干辣椒制品在5.0,10.0,25.0μg/kg加标水平的回收率为64.2%~81.6%,相对标准偏差(n=6)为1.3%~6.3%。该方法操作简单、灵敏度高、重现性好,可用于辣椒及辣椒制品中金刚烷胺残留量的检测。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

17.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

20.
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