食品包装材料中邻苯二甲酸酯类增塑剂迁移量的测定

建立了一种食品包装材料中邻苯二甲酸酯类(PAEs)增塑剂迁移量的检测方法。以正己烷为萃取溶剂对食品包装材料模拟液中17种PAEs进行提取,然后采用气相色谱-质谱联用法(GC-MS)进行检测。结果表明:17种PAEs的分离较好,方法检出限为0.14~0.30 mg/kg,线性范围0.5~8.0 mg/L,相关系数大于0.996,相对标准偏差(RSD)为2.2%~4.8%,回收率为95.0%~116.0%。该方法操作简便、准确、分离效果好,可同时检测食品包装材料中17种PAEs类增塑剂的迁移量。     

气相色谱–质谱法测定玩具涂层中6种邻苯二甲酸酯增塑剂

建立了气相色谱–质谱法测定玩具涂层中邻苯二甲酸二丁酯(DBP)、邻苯二甲酸丁苄酯(BBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)、邻苯二甲酸二正辛酯(DNOP)、邻苯二甲酸二异壬酯(DINP)、邻苯二甲酸二异癸酯(DIDP)等6种邻苯二甲酸酯类增塑剂的分析方法,确定了适宜的微波辅助萃取条件为:以二氯甲烷为萃取剂,萃取温度60°C,萃取时间25 min。在试验选定的条件下,以该方法测定玩具涂层中6种邻苯二甲酸酯类增塑剂,以峰面积对质量浓度线性回归,线性范围在0.5~50 mg/L,则相关系数大于0.999,最低检出限为0.5~1.0 mg/L,加标回收率在83.5%~105.6%之间,相对标准偏差小于5.8%。该方法操作简便快速,准确度和灵敏度高,适合于玩具涂层中6种邻苯二甲酸酯类增塑剂含量的同时测定。     

GC/ECD测定白酒中的邻苯二甲酸酯类化合物

建立了液液萃取-气相色谱法测定白酒样品中16种邻苯二甲酸酯的方法。方法表明16种邻苯二甲酸酯化合物能得到有效分离;在0.4~5 mg·L-1范围内,16种邻苯二甲酸酯的线性相关系数R2均大于0.996;加标回收实验表明,回收率在86.3%~99.0%之间,相对标准偏差2.4%~7.1%;检出限低于0.10 mg·kg-1。该方法具有分离度好,较宽的线性范围,简单快速等优点,能够满足白酒中邻苯二甲酸酯类化合物的日常检测。     

气相色谱-质谱法测定化妆品中16种邻苯二甲酸酯

建立了气相色谱-质谱法同时测定化妆品中16种邻苯二甲酸酯的分析方法。在邻苯二甲酸酯质量浓度为0.1 mg/L~100 mg/L范围内,该方法测得的峰面积值与邻苯二甲酸酯的质量浓度的线性关系良好。线性相关系数均大于0.99,检出限为0.5 mg/kg,回收率为83.3%~121.8%,相对标准偏差为0.5%~6.4%。     

水样中邻苯二甲酸酯类增塑剂检测的综合实验设计

建立固相萃取-气相色谱法同时测定水中6种邻苯二甲酸酯类增塑剂含量方法。选取C18固相萃取小柱对水样进行富集净化,在0.2~1000 mg/L范围,有良好的线性关系,相关系数均大于0.999,检测限0.15~0.3μg/L,回收率90.2%~101.3%,相对标准偏差1.4%~8.8%。该方法不仅适用各种水样邻苯二甲酸酯类增塑剂的分析检测,而且有利于培养学生综合运用知识进行科学研究的能力。     

气相色谱-质谱法测定油类和水类化妆品中21种邻苯二甲酸酯的含量

建立了气相色谱-质谱法测定油类和水类化妆品中21种邻苯二甲酸酯含量的方法。采用不同有机溶剂提取的方式对样品进行净化处理,在以甲基(5%苯基)聚硅氧烷为固定相的DB-5MS毛细管色谱柱(30 m×250 mm×0.25μm)中进行气相色谱分离,选取3种邻苯二甲酸酯类化合物的同位素作为内标,用质谱法进行测定。结果发现:21种邻苯二甲酸酯的线性质量浓度范围为0.01~10μg/mL,相关系数r0.999,检测限为0.02~0.68 mg/kg,平均回收率(n=9)为94.8%~103.7%。     

用索氏提取-气相色谱法测定PVC管材中的邻苯二甲酸酯类增塑剂

建立了索氏提取-气相色谱法测定聚氯乙烯(PVC)等管材中6种国家限量邻苯二甲酸酯(PAEs)类增塑剂的方法。采用索氏提取作为前处理提取手段,通过正交试验对样品中PAEs类增塑剂的提取条件进行系统优化。结果表明:在一定范围内,该方法具有良好线性关系,相关系数在0.997~0.999之间,检测限为0.15~0.60 mg/kg,平均回收率84.2%~109%,相对标准偏差为1.33%~8.60%。方法简单高效,具有良好的重现性和灵敏度,适用于PVC等管材中PAEs类增塑剂的分析检测。     

常规样品堆积-微乳毛细管电动色谱检测白酒中邻苯二甲酸酯类增塑剂

建立了常规样品堆积-微乳毛细管电动色谱检测白酒样品中常见的5种邻苯二甲酸酯类(PAEs)增塑剂的方法。考察了表面活性剂十二烷基硫酸钠浓度、缓冲液浓度和p H值以及进样时间对常规样品堆积模式富集效果的影响。结果表明,NSMMEEKC对5种PAEs的检测灵敏度(S/N=3)和常规微乳毛细管电动色谱法相比提高了8~10倍,检测限为0.05~0.1"g/m L,5种PAEs的平均回收率为85.7%~93.4%。该方法灵敏度较高,已应用于白酒样品中5种PAEs的检测,结果满意。     

气相色谱—质谱法测定食品塑料包装中柠檬酸酯类增塑剂

建立测定食品塑料包装中柠檬酸三乙酯(TEC)、柠檬酸三丁酯(TBC)、乙酰柠檬酸三丁酯(ATBC)、柠檬酸三辛酯(TOC)、等柠檬酸酯类增塑剂的检测方法。使用正己烷萃取柠檬酸酯类增塑剂,萃取液用气相色谱-质谱联用(GC-MS)测定。方法的检测限在0.05~1 mg/L之间,TEC、TBC、ATBC的线性范围在0.2~20 mg/L之间,TOC的线性范围在2~100 mg/L之间,相关系数r2大于0.997。4种柠檬酸酯类增塑剂加标回收率在82.7%~100%之间,相对标准偏差在3.6%~14.0%之间。运用该方法检测了20份食品塑料包装,未检出柠檬酸酯类增塑剂。     

GC-MS法同时测定塑料玩具中22种邻苯二甲酸酯增塑剂

建立了气相色谱-质(谱GC-MS)法,采用分段选择离子监(测SIM)模式,同时测定了塑料玩具中22种邻苯二甲酸酯(类PAEs)增塑剂的含量。结果表明:该方法具有良好的线性关系,相关系数均大于0.999,检测限在1.28~128.91mg/kg之间,平均回收率70.83%~107.95%,相对标准偏差3.61%~9.79%。该方法操作简单,灵敏度高重,现性好能,满足塑料玩具中PAEs含量的检测需求。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、环氧树脂、不饱和聚酯树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.