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1.
气相色谱/质谱法测定熏肉中的多环芳烃   总被引:22,自引:0,他引:22  
李永新  张宏  毛丽莎  孙成均 《色谱》2003,21(5):476-479
建立了熏肉中多环芳烃的气相色谱/质谱(GC/MS)测定方法。样品经正己烷-丙酮(体积比为1∶1)超声波提取、氧化铝柱净化后,用GC/MS分离测定。优化了25种多环芳烃(PAHs)化合物的分离测定条件。结果 25种PAHs回收率范围为48.5%-106.5%;日内(n=7)相对标准偏差为3.75%-7.95%。方法具有灵敏度高、准确度好、能同时分离测定20余种多环芳烃化合物的优点,适合于熏肉中多环芳烃化合物的分析测定。  相似文献   

2.
建立了气相色谱-串联质谱(GC—MS/MS)同时检测蔬菜中50种(38种有机磷、7种有机氮和5种拟除虫菊酯类)农药的多残留分析方法。采用凝胶渗透色谱(GPC)净化技术,用确定的二级质谱分析参数,以不同的电离方式(电子轰击电离EI或化学电离CI)一次分析所有的目标化合物。依次对农药标准品、空白洋葱样品进行GC—MS/MS分析,添加2个不同浓度水平的标准品进行方法的确证。大部分农药的回收率在60%~120%,RSD的范围为1.4%~16.9%,检出限为0.2~10μg/kg,满足农药多残留的分析要求。  相似文献   

3.
采用固相萃取-气相色谱/质谱(SPE-GC/MS)法同时测定了卷烟抽吸后滤嘴中截留的1-氨基萘、2-氨基萘、3-氨基联苯和4-氨基联苯四种芳香胺.该法采用5%的盐酸超声振荡提取滤嘴中的芳香胺,提取液经液液萃取后进行衍生化和固相萃取,浓缩后进行GC/MS分析.1-氨基萘、2-氨基萘、3-氨基联苯和4-氨基联苯的检出限分别为0.51、0.42、0.18、0.18 ng/mL,相对标准偏差在0.94%~3.02%之间,回收率在92.67%~97.20%之间.该方法用于卷烟滤嘴中四种芳香胺的测定,结果发现不同材料的滤嘴对四种芳香胺有不同的截留作用.  相似文献   

4.
报道了调味品中氯丙醇的衍生化气相色谱(GC/ECD)和衍生化气相色谱双串联质谱法(GC/MS/MS)测定。GC/ECD测定酱油中3—氯—1,2—丙二醇(3—MCPD)的检出限达到0.01mg/kg,回收率为91%~104%,变异系数为2.27%~7.96%;GC/MS/MS同时测定酱油中1,3—二氯—2—丙醇、2,3—二氯—1—丙醇和3—氯—1,2—丙二醇,1,3—二氯—2—丙醇、2,3—二氯—1—丙醇的检出限为0.02mg/kg,3—氯—1,2—丙二醇的检出限为0.01mg/kg,回收率在92%~106%,变异系数为3.51%~13.33%。  相似文献   

5.
建立了同时测定渔业养殖水中氢化可的松、泼尼松、醋酸可的松、睾酮、甲睾酮、黄体酮及苯丙酸诺龙等7种激素残留药物的超高压液相色谱-电喷雾电离串联质谱(UPLC-ESI-MS/MS)分析方法.水样用HLB固相萃取柱净化、浓缩后,洗脱液经氮气吹干,残渣用乙腈-水(V∶V=1∶1)溶解,以乙腈和0.1%甲酸水溶液为流动相,经ZORBAXSB-C18色谱柱分离后进行LC-MS/MS多反应检测模式作定性定量分析.方法在0.5~40μggL或1~40μg/L范围具有良好的线性,相关系数大于0.997,检出限(S/N=3)为0.03~0.3μg/L,平均回收率为74.8%~113.0%,相对标准偏差为4.0%~16%.方法适用于渔业养殖水中7种激素的检测分析.  相似文献   

6.
优化了土壤中16种优控多环芳烃( PAHs)的分析方法,建立了一套完备的质量控制体系,解决了PAHs分析中常见的技术难点,如苯并(a)芘(BaP)回收率低,基质复杂的样品净化效果不理想,萘(Nap)和菲(Phe)挥发损失和环境本底影响等.样品经加速溶剂提取(ASE),固相萃取(SPE)净化,逐级减压浓缩,气相色谱质谱( GC - MS)测定,并以氘代苯并a芘(BaP - d12)作回收率指示物.实验比较了3种正相SPE吸附剂的效果,发现弗罗里硅土对BaP存在明显的降解现象,BaP的定量应使用同位素稀释法,以降低其分析不确定度;氧化铝对PAHs的吸附性过强,不利于样品净化;硅胶最为理想.PAHs的仪器检出限为0.26~5.7 pg,方法检出限为0.067 ~0.97 ng/g(干重),土壤基质加标回收率为71%~ 122%,相对标准偏差为1.6%~8.3%.将该法用于7个电子废物焚烧区域农田土壤样品的测定,PAHs含量在28~ 283 ng/g(干重)之间,样品中BaP-d12的回收率为90%~124%,各项质控指标符合检测要求.  相似文献   

7.
本文报道了用气相色谱(GC)及气相色谱-质谱联用(GC/MS)检出人体液中一叶萩碱的方法.尿样经碱化后用乙醚直接萃取,回收率为72.1%;血浆样品用Sep-pak小柱提取,回收率为 43.9%,GC/MS的检测限为 20ng.方法快速、简便、准确.  相似文献   

8.
GC/MS方法分析豇豆中水胺硫磷等37种农药残留   总被引:1,自引:0,他引:1  
建立了GC/MS法同时测定豇豆中水胺硫磷等37种农药残留的方法.农药经过乙腈提取,NH2/CARBON复合固相萃取小柱净化,HP-5MS(30 m×0.25 mm×0.25 μm)弹性石英毛细管柱分离后,用GC/MS选择离子模式进行测定.农药在0.020~0.500 mg/L时与峰面积有良好的线性关系(r2>0.990...  相似文献   

9.
参照美国EPA525.1方法,C18-固相萃取膜萃取饮用水中的有机物,利用GC/MS法鉴定多环芳烃(PAHs),使用16种多环芳烃混合标准样绘制标准曲线,以内标法对PAHs进行定量分析.采用本方法研究某水厂经过深度处理后的出厂水中的7种多环芳烃的含量,PAHs的平均回收率为94.0%~97.7%.检测限为0.001μg/L.  相似文献   

10.
野生东北刺人参茎挥发油化学成分研究   总被引:6,自引:0,他引:6  
张宏  张宏桂 《分析化学》1993,21(6):679-681
本文用GC/MS方法分离鉴定了产于中国东北的药用刺人参的茎中20种挥发油成份。其中主要成份为醇类(68.9%)、醛类(17.6%).萜类(4.1%)。  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.
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   

13.
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   

14.
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   

15.
16.

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   

17.
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   

18.
The kinetics of the interaction between lithium carbonate and silica with various degrees of dispersion was investigated by TG and DTA methods. It was found that the utilization of pyrogenic silica with a specific surface area of about 300 m2g-1 instead of aerosil with one of 175 m2g-1 leads to an increase of the reaction rate between lithium carbonate and silica, which depends on the formation and growth of lithium orthosilicate crystals in the first stage, and is conditioned by the diffusion of lithium and oxygen ions through the lithium orthosilicate layer formed at temperatures above 800 K. This supposition is supported by the kinetic analysis results obtained with the use of the different models. The optimal regime of heating is recommended. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
小环化合物中饱和碳质子化学位移的计算   总被引:3,自引:0,他引:3  
小环化合物由于其张力、构型、构象和各向异性效应等原因,环碳上质子化学位移缺乏规律性,难以预测,对此作者曾提出一种近似算法。本文根据303种小环化合物中饱和碳质子的化学位移实验数据,将适于计算这类质子化学位移的公式表述为:  相似文献   

20.
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   

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