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961.
962.
Sediment samples of the Lippe river (Germany) taken between August 1999 and March 2001 were investigated by GC-MS-analyses. These analyses were performed as non-target-screening approaches in order to identify a wide range of anthropogenic organic contaminants. Unknown contaminants like 3,6-dichlorocarbazole and bis(4-octylphenyl)amine as well as anthropogenic molecular marker compounds were selected for quantification. The obtained qualitative and quantitative analytical results were interpreted in order to visualize the anthropogenic contamination of the Lippe river including spatial distribution, input effects and time dependent occurrence. Anthropogenic molecular markers derived from municipal sources like polycyclic musks, 4-oxoisophorone and methyltriclosan as well as from agricultural sources (hexachlorobenzene) were gathered. In addition molecular markers derived from effluents of three different industrial branches, e.g. halogenated organics, tetrachlorobenzyltoluenes and tetrabutyltin, were identified. While municipal and agricultural contaminations were ubiquitous and diffusive, industrial emission sources were spatially isolated. Specific seasonal trends of distribution patterns were not observed. 相似文献
963.
Gibb AR Suckling DM Fielder S Bunn B Jamieson LE Larsen ML Walter GH Kriticos DJ 《Journal of chemical ecology》2008,34(9):1125-1133
Two sex pheromone components of the gum leaf skeletonizer, Uraba lugens (Lepidoptera: Nolidae), recently established in New Zealand, were identified. Gas chromatography (GC) electroantennographic detection analyses of female pheromone gland extracts gave three compounds that consistently elicited antennal responses. Chemical analyses, using GC and GC-mass spectrometry, in conjunction with 4-methyl-1,2,4-triazoline-3,5-dione and dimethyldisulfide derivatizations, identified these compounds as (10E,12Z)-hexadecadien-1-yl acetate (E10,Z12-16:Ac), (10E,12Z)-hexadecadien-1-ol (E10,Z12-16:OH), and (Z)-11-hexadecen-1-yl acetate (Z11-16:Ac). A trapping trial in Queensland, Australia, in 2002, indicated that a blend of the two major components E10,Z12-16:Ac and E10,Z12-16:OH could attract gum leaf skeletonizer males. In the same trial, E10,Z12-16:Ac alone trapped large numbers of an unidentified nolid, Nola spp. Further trials in Auckland, New Zealand established that these two components were sufficient and necessary for trap catch of males; adding minor gland components, (10E,12E)-hexadecadien-1-yl acetate (E10,E12-16:Ac), Z11-16:Ac, or octadecan-1-ol (18:OH), to the two-component lure did not result in increased trap catches. Behavioral observations and gland analyses of the Auckland population revealed that female moths begin calling soon after emergence, with peak calling and pheromone production occurring 7 hr into the scotophase. Analysis of gland extract at two-hourly intervals during the first activity period showed that the ratio of E10,Z12-16:Ac to E10,Z12-16:OH (mean of 86: 14, respectively) and pheromone titer were fairly constant. No qualitative or quantitative differences in pheromone components were detected between gland extracts from Tasmanian univoltine and Auckland bivoltine populations of U. lugens. 相似文献
964.
Volatiles from Ips duplicatus male hindgut extracts and aeration samples of spruce logs colonized by the virgin males were analyzed by coupled gas chromatography–mass
spectrometry (GC-MS), coupled gas chromatography–electroantennographic detection (GC-EAD), and field trapping bioassays in
Inner Mongolia, China. GC-MS analyses showed that males from nuptial chambers (for reproduction) produced hindgut volatile
profiles similar to those of maturation feeding males from the nonreproductive galleries. The known aggregation pheromone
components, ipsdienol (Id) and E-myrcenol (EM) are the major constituents of this blend, followed by several minor bark beetle-related compounds: 2-methyl-3-buten-2-ol,
ipsenol, cis-verbenol, verbenone, 2-phenylethanol, myrtenol, and trans-myrtanol. The enantiomeric composition of the Id from the male hindgut extracts was determined to be a racemic mixture (50/50)
by enantioselective GC. GC-EAD experiments indicated that I. duplicatus antennae from both sexes responded strongly not only to the known aggregation pheromone components, Id and EM, but also to
the other minor conspecific-produced compounds. The strongest antennal response was elicited by the major pheromone component,
Id, which was ca. 2–3 times higher than that elicited by the second component, EM. Electroantennogram dose-responses indicated
that antennal response threshold to Id was approximately 100 times lower than that of EM. No synergistic effects between these
occurred at peripheral level. A strong and repeatable EAD response was found to a trace compound (flame ionization detection
undetectable) from both hindgut and aeration samples. The compound was identified as amitinol (At) based on the retention
time and a further EAD analysis of a synthetic mixture. In the field trapping experiments, At increased the attraction of
I. duplicatus to the traps baited with a binary blend of EM/Id (1:1) in a synergistic manner when tested at a low release rate (1:1:0.1)
but had no effect on catches at the high release rate (1:1:1). This result suggests that At might be a part of the Chinese
I. duplicatus aggregation pheromone system. The production ratios of EM/Id from the Inner Mongolian population (EM/Id ≈ 1:2.0–4) were twice
as high as those reported from Europe (EM/Id ≈ 1:9), corresponding well with the differences in the optimal response ratios. 相似文献
965.
The floral scent composition of 32 European and two Asian Salix L. species (Salicaceae) was analyzed. Intra- and interspecific variation was compared for a subset of 8 species. All Salix species are dioecious and floral scent was collected from both male and female individuals by using a dynamic headspace MicroSPE
method, and analyzed by GC-MS. A total of 48 compounds were detected, most of them being isoprenoids and benzenoids. Commonly
occurring compounds included trans-β-ocimene, cis-β-ocimene, benzaldehyde, d-limonene, α-pinene, cis-3-hexenyl aceatate, linalool, 1,4-dimethoxybenzene, and β-pinene. Two compounds, 1,4-dimethoxybenzene and trans-β-ocimene, were responsible for most of the interspecific variation. In a subset of eight extensively sampled species, six
had a characteristic floral scent composition; half of the pairwise species comparisons confirmed significant differences.
In three of these eight species, intraspecific variability could be explained by sex differences. Variation in Salix floral scent may provide specific signals that guide pollinators and thus contribute to the reproductive isolation of compatible
and cooccurring species. 相似文献
966.
建立了碱液处理-活性炭柱固相萃取结合气相色谱-串联质谱联用(GC-MS/MS)技术检测鱼干、虾皮和虾仁中N-亚硝基二甲胺(NDMA)、N-亚硝基甲乙胺(NMEA)、N-亚硝基二乙胺(NDEA)、N-亚硝基二正丙胺(NDPA)、N-亚硝基哌啶(NPIP)、N-亚硝基吡咯烷(NPYR)、N-亚硝基吗啉(NMOR)和N-亚硝基二正丁胺(NDBA)等有害物质。以NDMA-d6、NDPA-d14和NPYR-d8为内标, 用Ba(OH)2溶液于80 ℃处理样品1 h,离心上清液,经Sep-Pak® plus AC-2活性炭小柱富集净化,DB-WAXUI(30 m×250 μm×0.25 μm)色谱柱分离,质谱多反应监测(MRM)模式检测。结果表明,在1~200 μg/L浓度范围内,8种N-亚硝胺的线性关系良好,R2>0.998;检出限为0.03~0.25 μg/kg, 定量限为0.10~0.85 μg/kg,添加回收率为71.3%~119.0%(除NDBA在高添加水平时略低,为52.1%~69.0%),相对标准偏差为0.65%~15.4%。将该方法用于23种实际样品检测,在所有样品中均检出NDMA,且含量相对较高,其他N-亚硝胺仅部分检出,含量相对较低。该方法操作简单、便于高通量分析、环境友好、定性定量可靠,可为水产品中N-亚硝胺类物质的检测提供参考。 相似文献
967.
同位素稀释-气相色谱-串联质谱法测定猪肉中残留的4种β-受体激动剂 总被引:1,自引:0,他引:1
采用同位素稀释质谱法,结合固相萃取技术,建立了猪肉中克伦特罗、妥布特罗、溴布特罗、沙丁胺醇等4种β-受体激动剂残留量的气相色谱-串联质谱(GC-MS/MS)检测方法。向绞碎的猪肉中加入同位素内标克伦特罗-D9、妥布特罗-D9、溴布特罗-D9,经β-盐酸葡萄糖醛苷酶/芳基硫酸酯酶酶解,醋酸铵缓冲溶液提取,高氯酸调pH,HLB-MCX固相萃取柱串联净化,用-N,O-双三甲基硅基三氟乙酰胺(BSTFA)+1%三甲基氯硅烷(TMCS)衍生化后,进行GC-MS/MS测定,使用内标法定量。结果表明,猪肉中添加2.5~35.0 μg/kg水平的β-受体激动剂,回收率为92.2%~112.8%,批内变异系数(CV)为1.0%~12.6%,批间变异系数(CV)为1.9%~13.2%。4种β-受体激动剂的线性范围为1.35~158.00 μg/L,相关系数R2≥0.999 7,方法最低检测限为0.13~0.40 μg/kg,最低定量限为0.40~1.27 μg/kg。该方法精密度好、灵敏度高,可简便、准确地测定猪肉中4种β-受体激动剂的残留量。 相似文献
968.
云南昭通褐煤树脂物化学组成与分布特征 总被引:1,自引:0,他引:1
对云南昭通褐煤蜡树脂中游离酸、结合酸、树脂醇、树脂烃进行了GC-MS研究.结果显示,昭通树脂烃中D-环单芳藿烷及17β(H),21β-藿烷为含量最高的特征化合物,其它五环三萜及芳构化物质虽有分布,但量极低.树脂游离酸中正构烷酸为主要化学成分,C14~C30都有分布,其中C16,C18,C24,C28构成了含量上优势化合物,C16为含量最高的化合物.树脂结合酸中C14~C30正构烷酸其含量占绝对优势,并按C16>C18>C20>C22>C24>C26>C28顺序递减.树脂醇由C15~C30正构烷醇(C24,C26为该系列重要化合物)、C18,C23,C25,C27,C29-甲基酮,以及羽扇-3-酮、桦木-3-酮、24-甲基-5β(H)-胆甾烷-3β-醇、24-乙基胆甾-5、22-二烯-3β-醇、24-乙基-5α(H)-胆甾烷-3β-醇、23,24-二甲基胆甾-5-烯-3β-醇、C29-5β(H)、3β(OH)-甾醇等组成.稠环芳烃、松香酸、去氢松香等环状化合物含量很低或不存在,是昭通褐煤蜡与国内其它褐煤蜡组成的重大差别. 相似文献
969.
970.
云南丽江栽培玛咖的挥发性成分分析 总被引:2,自引:1,他引:1
云南丽江栽培玛咖中的挥发性成分采用GC-MS技术进行分析,总共鉴定出90个挥发性成分。石油醚浸出部分的挥发性主成分为t-丁基苄醚(26.00%)、N-苄基-乙酰胺(23.47%)和苯二甲酸己辛酯(23.49%);水蒸气蒸馏的油相部分挥发性主成分为2-甲基苯异腈(81.80%);水蒸气蒸馏水相乙醚萃取部分的挥发性主成分为苯腈(56.29%)、甲氧基乙醛(10.35%)。而主成分N-苄基-乙酰胺可以作为丽江栽培玛咖中石油醚提取的特征成分,作为质量控制标准之一。 相似文献