银掺杂氧化锌沸石复合物的制备和抗菌性能

采用共沉淀法制备沸石纳米氧化锌复合体,采用葡萄糖还原络合浸渍法制备不同载银量的银掺杂氧化锌沸石,考察银的负载量对物质结构和抗菌性能的影响.运用X射线衍射、SEM等方法对复合抗菌剂进行了分析、表征,结果表明:不同掺银量的沸石/ZnO样品除了有纤锌矿相ZnO的衍射峰外,还出现了少量AgO的衍射峰;随着银掺杂量的增多,复合抗菌剂表面出现很多的孔隙,但负载两次银(Ag:3+2％)的Ag-沸石ZnO出现的孔隙较少.采用滤纸片法、倍数稀释法测定抑菌环直径和最小抑菌浓度,研究不同银掺杂量的氧化锌沸石复合物的抗菌性能.结果表明:载银量为1％、3％、5％、3％+2％的银掺杂氧化锌沸石抗菌剂与未掺杂银的沸石氧化锌(即载银量为0％)相比,对金黄色葡萄球菌(S.aureus)、大肠杆菌(E.coli)和枯草芽孢杆菌(B.subtilis)的抗菌性能有一定的提高,其中载银量为3％的银掺杂氧化锌沸石复合物的抗菌效果较强;载银量为3％的银沸石氧化锌复合物对E.coli 的抑菌效果较明显,最小抑菌浓度为75.5 g/mL;对S.aureus和B.subtilis的最小抑菌浓度分别为250 μg/mL和435 μg/mL.     

氧化铈掺杂复合无机抗菌剂在LDPE中的应用研究

以氧化饰、无机抗菌剂、低密度聚乙烯（LDPE）等为原料，采用掺杂复合、双辊混炼等方法，制备抗菌LDPE材料，并进行分散性能、抗菌抑菌性能、力学性能的分析测试；结果表明：氧化铈掺杂复合无机抗菌剂，可改善无机抗菌剂与LDPE树脂的相容性．提高无机抗菌剂在LDPE材料中的分散均匀性。增强抗菌LDPE材料的抑菌性能和力学性能。     

含DCOIT的EVA发泡材料的防霉抗菌性能研究

以DCOIT(二氯辛基异噻唑啉酮)为抗菌剂,EVA(乙烯-醋酸乙烯共聚物)为主要原料,制备抗菌EVA发泡材料,进行了抑菌环试验和防霉抗菌性能测试。结果表明,DCOIT对绳状青霉、球毛壳、黑曲霉、出芽短埂霉均有显著的抑制作用,添加0.8%DCOIT的EVA发泡材料长霉等级为0级,具有强抗霉菌作用,对大肠杆菌和金黄色葡萄球菌的抗菌率分别达到99.92%和98.97%,抗菌性能优良。     

硫镧掺杂纳米TiO2的合成及其抗菌性能研究

以钛酸四丁酯为钛源,聚乙二醇200为分散剂,采用溶胶-凝胶法制备一种新型的硫镧掺杂纳米TiO2抗菌材料.通过透射电镜和X射线衍射对纳米材料的微观结构进行表征分析,并检测硫、镧掺杂对纳米TiO2抗菌性能的影响.结果表明,所制备的硫镧掺杂TiO2为锐钛矿型纳米晶,硫、镧的掺杂导致TiO2的粒径变小.抑菌试验结果显示,在日光灯和紫外灯照射下,所制备的硫镧掺杂TiO2纳米材料具有良好的抗菌性能,在日光灯照射下抗大肠杆菌和金黄色葡萄球菌的最小抑菌浓度MIC值均≤250 mg/mL.通过与纯的TiO2对比,掺杂硫镧TiO2的抑菌效果更明显,且其抗菌性能与掺杂硫镧的含量成正相关.     

纳米银修饰介孔二氧化钛及其可见光下光催化抗菌性能的研究

以P123为模板制备介孔二氧化钛(m-TiO_2),借助光还原法制备m-TiO_2-Ag复合材料。利用透射电镜(TEM)、X射线衍射仪(XRD)、傅里叶变换红外光谱(FT-IR)等对m-TiO_2-Ag复合材料进行表征。以甲基橙(MO)和罗丹明B(RhB)为脱色降解模型,测定质量分数不同的载Ag样品在可见光下光催化性能。利用生长曲线和抑菌环检测其抗菌性能。结果表明,纳米银掺杂可以显著提高介孔二氧化钛(m-TiO_2)在可见光下催化降解染料的性能,并对测试菌展现出良好的抗菌性。     

均苯三甲酸银[{Ag(H2btc)}{Ag2(Hbtc)}]n配位聚合物的光催化性能和抗菌性能研究

采用1,3,5-苯三甲酸(H₃btc)与硝酸银(AgNO₃)在MeOH/H₂O混合溶液中通过自组装反应构建出[{Ag(H₂btc)}{Ag₂(Hbtc)}]n配合物。利用扫描电镜(SEM)、X-射线粉末衍射仪(XRD)、傅里叶变换红外光谱(FT-IR)对材料的形貌和组成进行表征。以亚甲基蓝(MB)和罗丹明B(RhB)为脱色降解模型,测定样品可见光下的光催化降解性能。通过抑菌环、生长曲线和最小抑菌浓度(MIC)检测其抗菌性能。结果表明所得的化合物材料纯度较高,具有良好的可见光下光催化性能和抗菌性能。     

纳米无机抗菌剂对聚丙烯性能的影响

聚丙烯(PP)在使用过程中容易受到有害微生物的污染,采用双螺杆挤出机将纳米无机抗菌剂与聚丙烯进行熔融共混制备了抗菌PP,研究了抗菌PP的力学性能和抗菌性能。采用扫描电镜观察纳米无机抗菌剂在PP中的分散情况;通过原子吸收分光光度计测定了抗菌剂中银离子的溶出量。结果表明:添加4种纳米无机抗菌剂的PP均具有抗菌效果。其中,当RHA-M型抗菌剂添加量为0.2%时,抑菌环直径最小,为8.5 mm;当RHA-M型抗菌剂添加量为1.0%时,抑菌环直径最大,为30.1 mm;银离子溶出实验说明PP复合材料具有一定的抗菌持久性;通过测试该抗菌PP的拉伸强度和冲击强度,表明4种抗菌剂的加入对PP的性能影响较小。     

丙酸钙改性CP-EF抗菌防霉薄膜的制备及性能研究

以丙酸钙(CP)和实验室自制的改性抗菌防霉(EF)树脂为改性剂,与低密度聚乙烯(LDPE)共混造粒流延成改性CP-EF抗菌防霉薄膜,研究了改性EF树脂含量的变化对薄膜力学性能、光学性能、阻隔性能、微观结构、热稳定性能及抑菌性的影响。结果表明,改性EF树脂的加入提高了薄膜的阻隔性、雾度、热稳定性和抑菌性,但是薄膜透光率降低。当丙酸钙含量为2.5%,改性EF树脂含量为4%时,薄膜的力学强度及抗菌防霉效果较好,可作为食品包装材料。     

L-精氨酸改性淀粉的制备及其抗菌薄膜的性能

以玉米淀粉(St)、丙烯酸甲酯(MA)与L-精氨酸(L-Arg)为原料,采用酯化-氨解两步法,制备了具有抑菌性能的精氨酸改性淀粉(St MA-Arg)。阐述了反应机理,用拉曼光谱、~(13)CNMR、XRD与GPC表征了产物的结构,通过单因素实验优化了反应条件。以St MA-Arg为原料制备了抗菌膜,考察了L-Arg固载率(IR)对薄膜的亲疏水性能、力学性能及抑菌性能的影响。结果表明,St MA-Arg薄膜的力学性能较天然淀粉膜显著改善,同时疏水性增强。固载率(IR)为7.48%的St MA-Arg及其薄膜对大肠杆菌(E.coli)显示出明显的抑菌活性,且膜的抑菌较小,属接触式抑菌。土壤失重实验结果显示,St MA-Arg(IR=7.48%)薄膜40d后的失重率为27.90%,远小于天然淀粉膜(40 d失重率为72.15%)。有望成为一种潜在的环境修复材料的基体。     

喹诺酮类抗菌材料制备及性能研究

采用熔融共混挤出的方式将环丙沙星和医用聚氨酯(TPU)材料共混制备抗菌TPU材料,研究了不同添加量的环丙沙星对TPU材料物理性能、抗菌性能的影响,同时研究了抗菌TPU材料在PBS缓冲液中的累积释药量。结果表明:环丙沙星对大肠杆菌和金黄色葡萄球菌的最小抑菌浓度(MIC)分别为0.05μg/mL和5μg/mL;当环丙沙星的添加量为1%时,抗菌材料的物理性能最优,对大肠杆菌和金黄色葡萄球菌均有抗菌作用;抗菌TPU材料中的环丙沙星在PBS缓冲液中144 h的累积释放率仅0.07%,24 h释放环丙沙星的浓度为0.098μg/mL,高于环丙沙星对大肠杆菌的最小抑菌浓度。     

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

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.     

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。