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直接胺化缩合制备葡萄糖胺为化合物 总被引:1,自引:0,他引:1
在催化剂存在条件下,通过对葡萄糖与一乙醇胺或乙二胺的直接胺化缩合反应的研究,制备了N-葡萄糖基-乙醇胺和N,N′-双葡萄糖基-乙二胺,考察了反应温度,时间及催化剂用量对该类反应产物产率的影响。 相似文献
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合成了一种新型兼有植物生长调节剂和除草剂功效的N-硝基-N-(2,4,6-三氯苯基)-N′-3-甲基苯基脲,并经元素分析,红外光谱等证实了它们的结构。 相似文献
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N,N-二烷基苯胺硝化反应的研究 总被引:2,自引:0,他引:2
间硝基-N,N-二烷基苯胺是重要的染料中间体,亦可用作医药、农药及感光材料类的原料.目前工业上主要通过将间二硝基苯还原为间硝基苯胺、酰化、还原、烷基化方法制备;或将间二硝基苯用铁粉还原成间苯二胺,转化成单盐酸盐,酰化、烷基化方法制得[1].本文利用工业上制备N-烷基苯胺时产生的副产物N,N-二烷基苯胺为原料,经与浓H2SO4成盐后,用混酸硝化可得到间硝基-N,N-二烷基及对硝基-N,N-二烷基苯胺.其中对位与间位的摩尔比近似为1:1,未发现有邻位异构体生成.产品可在不同pH值下分离,间位异构体为液体,而对位为固态,N,N-二烷基苯胺的转化率可达99%以上.纠正了文献中认为-N+R2为间位定位基的说法.该合成路线为制备上述产品提供了新途径. 相似文献
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以联苯胺和二苯胺为原料,经两步反应合成了N,N,N′,N′-四苯基联苯胺(TPB)。与已报道的方法相比较,该方法具有产率高、操作简单、原料价格低廉等优点。 相似文献
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N,N—二甲基—N′—月酰基—1,3—丙二胺的合成 总被引:2,自引:0,他引:2
以月桂酸和N,N-二甲基-1,3-丙二受为原料,合成了N,N-二甲基-N′-月桂酰基-1,3-丙二胺,通过改变反应温度,酸胺的量比和投料方式,探索反应的优化条件。结果显示,当反应温度为160℃,n(月桂酸):n(N,N-二基-1,3-丙二胺)=1.00:1.10,N,N-二甲基-1,3丙二胺按40min连续滴加时,产物的游离酸值最低,为5.54mg/g。产品的红外光谱与标准样品的谱图相符。 相似文献
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聚丙烯酸铵增稠剂的制备工艺 总被引:2,自引:0,他引:2
介绍了以丙烯酸、氨水、煤油、N,N-亚甲基双丙烯酰胺、过硫酸钾、乳化剂等为原料制备聚丙烯酸铵增稠剂的工艺。讨论了氨水用量、中和反应时间、聚合反应温度、煤油用量、交联剂用量、引发剂用量等因素对聚丙烯酸铵增稠剂产品吸水性和增稠性能的影响。实验结果发现,当丙烯酸58g、氨水50g、中和反应时间2h、煤油40.8g、N,N-亚甲基双丙烯酰胺0.133g、相对分子质量调节剂(适量),过硫酸钾0.266g、乳化剂6g、聚合反应温度为65℃、聚合反应时间2h,得到的产品吸水量大,增稠性能良好,粘度≥2200mPa.s。 相似文献
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N,N-二甲基-4-羟基丁酰胺是医药和化妆品的重要原料,曾有专利报道其合成方法,但精制困难、纯度低。本专利提供的制备方法不仅产品收率高,纯度亦佳。 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
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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