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1.
王诚刚 《广州化工》2009,37(8):138-139
采用分子印迹技术,以咖啡因为模板分子,丙烯酰胺为功能单体,二甲基丙烯酸乙二醇酯为交联剂,偶氮二异丁腈为引发剂,在氯仿中本体聚合方式制备了咖啡因分子印迹聚合物。紫外分光光度法对功能单体与模板分子之间聚合进行考察,结果表明,通过咖啡因分子印迹聚合物的制备,可实现咖啡因与结构类似物的分离和精制。  相似文献   

2.
以甲基丙烯酸为单体、二乙烯基苯为交联剂、苯胺为模板分子,利用沉淀聚合法通过改变溶剂等条件制备了单分散苯胺分子印迹聚合物微球。通过扫描电子显微镜表征微球表面形貌幵测量微球尺寸,通过纳米粒度分析仪验证微球单分散性。经气相色谱表征,该分子印迹聚合物对苯胺最大静态吸附量为12.98 mg/g,具备对苯胺分子的特异性识别能力。  相似文献   

3.
以苏丹红为模板分子,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,在乙腈中采用沉淀聚合法制备分子印迹聚合物。研究了模板分子与功能单体的相互作用和最佳比例,探讨了超声波/离心提取工艺对分子印迹聚合物洗脱的影响,对合成的分子印迹聚合物进行静态吸附实验、吸附动力学实验以及Scatchard分析。结果表明,在相同条件下,与非印迹聚合物相比,分子印迹聚合物对苏丹红有良好的吸附性能。  相似文献   

4.
乙酰水杨酸分子印迹聚合物微球的制备及性能研究   总被引:1,自引:0,他引:1  
以乙酰水杨酸为模板分子,采用沉淀聚合的方式制备了对乙酰水杨酸具有高选择性和亲和性的分子印迹聚合物微球。通过紫外光谱分析法考察了模板分子与功能单体作用规律,优选了功能单体与配合比例。等温吸附实验的结果显示,与相应的空白聚合物相比,印迹聚合物对模板分子具有更高的亲和性;Scatchard数学模型分析的结果表明,印迹聚合物中主要存在一类亲和性质相同的结合位点,其最大表观结合量为37.97 mg/g。选择性吸附实验表明,制备的印迹聚合物对模板分子具有良好的选择性识别能力。  相似文献   

5.
采用分子印迹技术,以α-甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,乙腈为致孔剂,合成以硫丹为模板的印迹聚合物微球。首先利用紫外光谱方法研究了模板与功能单体相互作用情况,采用平衡吸附试验对印迹聚合物吸附效率进行了表征,与化学组成相同的空白聚合物相比,印迹聚合物微球对模板分子具有更高的吸附效率,按最佳合成条件得到的印迹聚合物最大表观吸附量达42.56 mmol/g。  相似文献   

6.
以二乙烯基苯(DVB)为单体,偶氮二异丁腈(AIBN)为引发剂,乙腈为溶剂,用沉淀聚合法合成了高交联度的聚合物微球。讨论了反应时间、反应温度、转动速率、单体浓度以及引发剂浓度对聚合物微球粒径及粒径分布的影响,并用扫描电子显微镜(SEM)进行了表征。  相似文献   

7.
以对羟基苯甲酸乙酯为模板,α-甲基丙烯酸为功能单体,甲基丙烯酸乙二醇酯为交联剂,偶氮二异丁腈为引发剂,用沉淀聚合法制备对羟基苯甲酸乙酯分子印迹聚合微球.通过一系列的单因素实验优化了聚合反应条件,通过正交实验得出,在模板分子、功能单体、交联剂物质的量比例为1∶6∶20,反应温度为65℃的条件下合成的印迹聚合物的吸附量最大.以紫外,可见分光光度计对印迹聚合物的吸附性、选择性进行了分析.以优化后的反应条件合成的印迹聚合物对对羟基苯甲酸乙酯的相对吸附量为866.55 μg/g,同等条件下非印迹聚合物的结果为406.72 μg/g.  相似文献   

8.
马红玲  苏立强 《化工时刊》2010,24(12):18-20
以烟酰胺为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,乙腈为溶剂,采用沉淀聚合法制备了烟酰胺分子印迹聚合物,通过静态平衡吸附和色谱分析对印迹聚合物进行表征,结果表明,印迹聚合物对烟酰胺分子具有很好的吸附能力和特异识别性。  相似文献   

9.
以石墨烯量子点(GQDs)为荧光组分,异丙威为模板分子,甲苯/石蜡混合溶剂为致孔剂,甲基丙烯酸为功能单体,三羟甲基丙烷三丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,采用热引发沉淀聚合法制备了对异丙威有吸附作用的异丙威荧光分子印迹聚合物。结果表明:异丙威荧光分子印迹聚合物表面凹凸不平,直径较大;其与甲基丙烯酸之间以非共价键结合;荧光分子印迹聚合物内部存在大量印迹"空洞"或"孔穴",对高温有一定的耐受性;异丙威荧光分子印迹聚合物具有良好的吸附性、荧光性、选择特异性,可为环境、食品中农药痕量残留检测提供一种新途径。  相似文献   

10.
利用辉光放电等离子体代替传统化学引发剂,以亚甲基蓝为模板分子,丙烯酰胺为单体,N,N-亚甲基双丙烯酰胺作交联剂,采用沉淀聚合法制得分子印迹聚合物,用红外光谱和扫描电镜对其进行了表征。吸附实验表明印迹聚合物在20min达到吸附平衡,印迹聚合物对模板分子吸附量随浓度增加而增加,等离子体引发制备的印迹聚合物吸附量大于化学引发剂制得的印迹聚合物。扫描电镜结果表明等离子体引发制得的分子印迹聚合物颗粒粒径小、表面粗燥、孔穴多、比表面积大。采用等离子体引发制得的分子印迹聚合物对模板分子的吸附常数和最大吸附量分别为0.1528 L/mg和33.62 mg/g。  相似文献   

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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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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   

15.
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   

19.
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   

20.
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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