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溶剂型木器涂料中挥发性有机化合物释放规律 总被引:2,自引:0,他引:2
小型气候箱模拟典型室内空气条件,不同时间用椰子壳活性炭吸附管收集一定体积硝基、多组分聚氨酯清漆涂膜释放出的VOC与空气的混合气体,气相色谱法测定二硫化碳提取液中VOC组分浓度的实验方法,研究了溶剂型木器涂料成膜后VOC的气相浓度由迅速衰减、过渡和缓慢衰减三个过程构成并受液-气界面压力差和解吸的控制,基于数据分析建立定量描述涂料涂装后气相浓度与涂膜中VOC组分量、空气交换率、实验仓容积相互关系的数学模型。气相浓度的衰减率R,可表征VOC释放特性,温度、湿度、空气交换率条件对气相浓度衰减率影响研究表明其与温度、组分的色谱保留时间存在函数关系。 相似文献
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采用吸附管、苏码罐采集大气中的VOC,比较了两种方法的检测结果、优缺点。得出结论:采集环境样品(浓度比较低)应该采用苏码罐采样,采集污染源应采用吸附管采样。 相似文献
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介绍了高密度聚乙烯管(PE-HD)、交联聚乙烯管(PE-X)和硬质聚氯乙烯管(PVC-U)中的挥发性有机成分向水中的迁移测定研究。PE-HD中主要的迁移成分是2,4-二-间-丁基-苯酚(2,4.-DTBP),是酚类抗氧化剂的降解产物,除此之外降解产物还有醋、乙醛、酮、芳香烃和菇类化合物。根据塑料管接触水的极限臭味值(TON)估测,在测试的7种PE-HD管材中有5种PE-HD管的TON-4; 2种PE-HD管释放到水中挥发性有机物(VOC)的总量基本恒定;PEX管迁移实验显示大量的VOC迁移到水中(TON-5),其中一些迁移的VOC成分不确定;HPVC管向水中迁移的挥发性物质很少。 相似文献
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活性炭上CS2与CO2混合气体的吸附模型 总被引:4,自引:1,他引:3
利用纯气体的等温吸附数据,研究了303K下CS2与CO2混合气体在活性炭上的等温吸附行为.采用两种混合气体模型方程即扩展的Langmuir修正式和Lewis关系式模拟混合气体的等温吸附,结果显示,分别以纯气体的Langmuir方程和D-R方程为基础的Langmuir修正式和Lewis关系式均能较好地描述混合气体的等温吸附,且误差均小于士5%.混合气体中CS2的吸附量约为COz吸附量的20倍.CS2与CO2混合气体在活性炭上的等温吸附以对CS2的吸附为主. 相似文献
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高压下煤对CH4/CO2二元气体吸附等温线的研究 总被引:7,自引:0,他引:7
研究了晋城和潞安煤在高压下对纯 CH4,CO2 及其二元混合气体的吸附特性 ,在对混合气体绝对吸附量计算公式推导的基础上 ,对绝对吸附等温线进行了研究 .结果表明 :高压下煤对混合气体的吸附介于纯 CH4和 CO2 之间 ,Gibbs吸附等温线和绝对吸附等温线表现出较大的差异 ;煤对混合气体中 CH4和 CO2 的吸附呈现出不同的吸附特点 ;煤对 CO2 优先吸附 ,并且随着压力的升高 ,煤对 CO2 选择性吸附能力增加 .本研究结果对开展注烟道气提高煤层采收率和煤层埋藏CO2 具有一定的指导作用 . 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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. 相似文献
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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively.
There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized.
High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without
the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of
fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to
achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic
SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve
F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender
particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing,
and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing
or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually
preserves suspension stability during freezing.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago,
IL. Tied for first place in The John A. Gordon Best Paper Competition. 相似文献
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Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae
and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted
in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures
(release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species
(Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species
to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were
exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of
separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles
from the southeastern region of the US. 相似文献
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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. 相似文献
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006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生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。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(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。 相似文献
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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008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、不饱和聚酯树脂、环氧树脂)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. 相似文献