共查询到20条相似文献,搜索用时 203 毫秒
1.
建立了检测鸡肉中甲硝唑MNZ、二甲硝唑DMZ及其代谢物羟基甲硝唑MNZOH(甲硝唑代谢物)、1-甲基-5硝基-2-羟甲基咪唑HMMNI(二甲硝唑代谢物)残留的超高效液相色谱-串联四级杆质谱(UPLC-MS/MS)残留分析方法。样本在乙腈水溶液提取下经PRIMEHLB固相萃取柱净化,氮吹浓缩后定容过膜上机检测。在1.00~100.0μg/L线性范围内,甲硝唑、二甲硝唑、羟基甲硝唑、羟甲基甲硝咪唑的标准曲线相关系数分别为r=0.99881、r=0.99694、r=0.99975、r=0.99713,方法检出限分别为0.128μg/kg、0.123μg/kg、0.183μg/kg、0.158μg/kg。加标回收试验中甲硝唑、二甲硝唑、羟基甲硝唑、羟甲基甲硝咪唑的加标浓度分别为1.00、2.00、10.0μg/kg,回收率范围分别为81.5%~105.0%,84.5%~102.0%,87.0%~104.0%,87.0%~106.0%。此方法适用于鸡肉中甲硝唑、二甲硝唑及其代谢物残留的检测。 相似文献
2.
采用固相萃取(SPE)净化技术和高效液相色谱-串联质谱仪(HPLC-MS/MS),研究并建立了同时测定祛痘化妆品中6种硝基咪唑类药物(甲硝唑、替硝唑、奥硝唑、地美硝唑、洛硝唑和塞克硝唑)的方法。样品用酸化乙腈溶液提取,阳离子固相萃取小柱净化,以体积分数为0.1%甲酸乙腈溶液-体积分数为0.1%甲酸水溶液为流动相,经C18色谱柱梯度洗脱分离,采用HPLC-MS/MS多反应监测模式(MRM)定量检测。结果表明,6种硝基咪唑类药物在质量浓度1.0~50.0μg·L-1内线性关系良好,相关系数均大于0.999;方法定量限均为0.5 mg·kg-1;在祛痘水和祛痘膏样品中进行3个水平的添加实验,平均回收率为89.7%~108.0%,相对标准偏差(n=6)为2.3%~6.5%。 相似文献
3.
采用固相萃取净化技术和超高效液相色谱-串联质谱方法(UPLC-MS/MS),建立了测定祛痘化妆品中4种林可胺类化合物(林可霉素、克林霉素、克林霉素磷酸酯和吡利霉素)的分析方法。样品用酸化乙腈提取,阳离子交换固相萃取小柱(MCX)净化,以乙腈-10mmoL/L乙酸铵溶液(pH 3.0)为流动相,经C18色谱柱梯度洗脱分离,电喷雾正离子模式电离,多反应监测模式检测,外标法定量。结果表明,4种林可胺类化合物的方法定量限(LOQs)均为10μg/kg;在5~200μg/L范围内线性关系良好,相关系数均大于0.999 0;在祛痘膏、祛痘水样品中进行10、100、1 000μg/kg 3个添加水平试验,平均回收率范围为87%~105%,相对标准偏差(n=6)在3.3%~10.2%之间。采用此方法测定了祛痘化妆品中林可胺类化合物的含量水平,发现存在违规添加现象。 相似文献
4.
硝基咪唑类化合物是由咪唑在浓硫酸中硝化而得,它们中多数是重要的医药中间体,如2-硝基咪唑类化合物可以明显增加体外乏氧细胞放射增敏活性,并表现出较强的体内抑制血管增出活性;5-硝基咪唑是重要医药中间体,如常用的消炎抗感染药物甲硝唑、替硝唑、奥硝唑、塞克硝唑等都属于5-硝基咪唑类化合物,其中甲硝唑、 相似文献
5.
6.
《香料香精化妆品》2017,(2)
建立了一种简单、快速测定化妆品中4种咪唑类抗真菌药物(益康唑、咪康唑、联苯苄唑和芬替康唑)的QuEChERS萃取净化-超高效液相色谱串联质谱分析方法。样品经乙腈提取,N-丙基乙二胺(PSA)吸附剂净化,高效液相色谱分离,四极杆电喷雾离子源正模式及多反应监测模式检测,外标法定量。4种咪唑类抗真菌化合物在0.5~100.0μg/L范围内线性关系良好,相关系数均大于0.9980,方法的定量限为5.0μg/kg,加标回收率为82.5%~104.4%,精密度(n=6)为3.2%~6.5%。该方法具有净化效果好、定量准确、灵敏快速的特点,适用于化妆品中咪唑类抗真菌药物化合物的检测确证。 相似文献
7.
8.
9.
10.
11.
乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
12.
13.
The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献
14.
D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
15.
16.
Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
17.
18.
19.
杀虫磺缓释剂杀钉螺试验报告 总被引:1,自引:0,他引:1
杀虫磺缓释剂浸杀成螺、幼螺、螺卵效果好,现场应用缓释片63克/米^2,半年后活螺平均密度下降93.2%,春季施药1次,可达到控制当年钉螺的扩散。 相似文献
20.
醋酸纤维素取代基分布与性质的关系 总被引:9,自引:0,他引:9
分析了以吡啶为溶剂的醋酸纤维素的13C-NMR核磁共振谱,得出了三种不同位置羟基的取代度。结合X—射线和DSC分析,初步说明具有相同取代度但未经水解和经过水解的醋酸纤维素(CA) 性质上的差异是由于三个羟基上的取代度分布不同及消晶程度差异所致。 相似文献