金属离子掺杂硅胶吸附剂的性能与结构表征

以陶瓷纤维纸为基材,钴盐、铝盐或钛盐为改性剂,顺次经水玻璃、酸性盐溶液浸渍共沉积制得金属离子掺杂硅胶吸附剂。采用扫描电镜、多孔介质空隙分析仪、光电子能谱仪表征改性吸附剂组成、表面形貌、孔径大小及分布;用程序升温脱附谱,热失重分析仪等检测材料的脱附性能及热稳定性。结果表明:金属离子掺杂硅胶均匀分布在陶瓷纤维纸表面及其空隙中;经掺杂后的硅胶,其吸附性能、Brunauer-Emmett-Teller(BET)比表面积、孔容、平均孔径明显增加。改性硅胶的BET表面积、饱和吸附量及热稳定性按照铝掺杂硅胶、钛掺杂硅胶、钴掺杂硅胶及硅胶的顺序递减。     

陶瓷基硅胶吸附材料的实验研究

采用浸渍法制得陶瓷基硅胶吸附材料,探讨了水玻璃质量分数、絮凝剂质量分数、盐酸浓度等条件对硅胶吸附性能的影响,采用扫描电镜(SEM)和孔隙分析仪揭示吸附材料的表面形貌及结构,结果显示,当水玻璃质量分数为26. 67 %、絮凝剂质量分数为15%,盐酸浓度为0. 5mol/L时,吸附剂具有较好的吸附性能,硅胶能均匀覆盖在纤维表面及其空隙中,其孔径落在纳米尺度范围内。     

硅胶/分子筛复合物的制备及吸附性能

以硅溶胶为分散剂和粘合剂,在陶瓷纤维纸上浸渍反应生成了高性能的硅胶与分子筛复合物.讨论了硅溶胶浓度、分子筛含量等对复合物吸附性能的影响.光学显微照片显示:分子筛能较好地分散在硅溶胶中.扫描电镜照片显示:分子筛颗粒较均匀地分散在陶瓷纤维纸的表面及空隙中.静态法吸附性能测试结果显示:低湿度下,硅胶/分子筛复合物的吸附性能优于硅胶的;高湿度下,硅胶/分子筛复合物的吸附性能优于分子筛的.     

新型吸附材料除湿轮传递过程及性能优化

陶瓷纤维纸经水玻璃、铝盐溶液等浸渍及调节溶液pH值得到新型高吸附性能Al3+掺杂硅胶吸附材料。文中建立了除湿轮传热传质数学模型和实验装置,通过模拟结果和实验数据对Al3+掺杂硅胶除湿轮的吸附性能进行了研究,分析了转速、解吸角及通道尺寸对除湿轮吸附性能的影响。结果显示,在综合考虑传递单元数及空气流通阻力后,通道尺寸最优值为1.34 mm×4.35 mm;除湿轮的最佳转速取决于其厚度,而与解吸角无关,当厚度为0.15—0.3 m时,其最佳转速为10 r/h;对厚度为0.2 m的除湿轮,优化后转速及解吸角分别为10 r/h和90°。在上述优化的参数下,新型吸附材料除湿轮显示出较好的工作性能。     

铝改性硅胶吸附剂材料及其制备方法

本发明公开了一种铝改性硅胶吸附剂材料的制备方法，包括下述步骤：（1）室温下将无机纤维纸浸渍在水玻璃中，2～5h后取出，十燥10～24h；（2）将可溶性铝盐配成水溶液，并加稀酸调节溶液pH值0．5～2，升温至30～80℃，强力搅拌下，将所得溶液浸渍上述无机纤维纸，在无机纤维的表面及其空隙中发生共沉淀反应，充分反应12～24h；（3）将反应后的无机纤维纸取出，用清水冲洗至pH为中性，取出晾干，采用程序升温处理得到铝改性硅胶吸附剂材料。由上述方法制备的铝改性硅胶吸附剂材料具有吸附量大．除湿效率高，再生温度较低，耐热性能好，机械强度高，使用寿命长的优点，能广泛应用于除湿转轮的生产制造。     

钛掺杂硅胶块体吸附剂

以陶瓷纤维纸片为基材,顺次经水玻璃、酸性钛盐溶液浸渍共沉淀制得新型陶瓷基钛掺杂硅胶块体吸附剂.多孔介质表面分析显示:掺杂硅胶孔径在0.5～6 nm范围,以中孔为主.Fourier变换红外谱在波数954 cm 1处的特征吸收峰表明吸附剂中形成了Si-O-Ti键.根据掺杂前后固体魔角核磁共振硅谱中硅原子化学位移的变化(向高场方向移动)及X射线光电子能谱中各原子结合能的变化(Ti2p3/2的结合能随钛含量的增加而增加,而Si2p,O1s的结合能则呈相反趋势)进一步表明:钛原子替代硅原子进入硅胶网络.热重分析及烧结实验结果显示:钛掺杂吸附剂具有更好的热稳定性.新型吸附剂优异的吸附性能除了与其高的比表面积相关外,还与Ti-O键对水分子的亲合力紧密相关,其耐热性能增强与形成高热稳定性Ti-O Si键及材料表面导热性能提高有关.     

铝盐掺杂TiO2棒状纤维的制备及其室温NOx气敏性

以钛酸四丁酯为钛源、Al(NO3)3为铝盐,采用静电纺丝法在600℃焙烧条件下制备出铝盐掺杂TiO2棒状纤维.利用扫描电子显微镜、透射电子显微镜和X射线衍射仪等对纤维的形貌和组成进行了表征.研究了室温下铝盐掺杂TiO2纤维对NOx的气体敏感性能,并对其气敏机理进行了分析.结果表明:铝盐掺杂TiO2纤维为一维棒状结构,直径约为200nm.在室温条件下对NOx有较好的气敏响应,响应时间最短为6s,最低检测体积分数可达9.7×10-7.锐钛矿相的存在有利于NOx的吸附-脱附.铝盐掺杂TiO2纤维大幅提高了对NOx的气敏响应灵敏度,是一种在室温条件下极具潜力的气敏材料.     

低温开放体系配阴离子对合成硅基铝多孔材料的影响

以十六烷基三甲基溴化铵为模板,六水氯化铝和十八水硫酸铝在低温开放体系分别与正硅酸乙酯直接进行固/液反应,合成非晶结构的铝掺杂氧化硅微介孔材料。并用XRD、HRTEM、SEM/EDS、低温N2吸附、FTIR和原子吸收光谱TAS等技术对产物的结构和吸附性能进行表征。探讨了微介孔的形成机理。结果表明,在酸性和阳离子表面活性剂共存条件下,所制得的铝掺杂氧化硅微介孔材料呈不规则形状,其孔壁均为无定型;掺杂金属铝进入氧化硅晶格。铝源中配阴离子不仅影响材料的物相织构、材料的元素组成,而且还影响其吸附性能。     

采用氢氧化钾-氢氧化钠复合活化剂制备炭微球吸附材料

以中间相炭微球(MCMB)为原料,以掺杂一定比例氢氧化钠的氢氧化钾为活化剂,采用化学活化法制备了炭微球吸附材料。通过甲基橙吸附和孔隙比表面积测试分析了活化产物的吸附性能,研究了碱炭比、活化温度和氢氧化钠掺杂比例对材料吸附性能的影响。结果表明:碱炭比和活化温度均对材料的吸附性能产生影响,活化剂中掺杂适量的氢氧化钠可提高材料的比表面积和吸附能力。当碱炭质量比为6、活化温度为800℃、氢氧化钠掺杂比例为33%(质量分数)时,制备的吸附材料对甲基橙的吸附效率最高达到98.6%,吸附-脱附等温曲线属于I型吸附等温线,吸附材料以微孔为主并存在少量中孔,比表面积为1 694.2 m2/g。     

陶瓷纤维催化剂载体的制备及其性能

利用陶瓷纤维毡为原料,通过适当的成型工艺将纤维毡制备成陶瓷纤维催化剂载体.探讨浸润助剂(十二烷基硫酸钠,SDS)用量、纤维毡的干燥工艺及黏结剂浓度对陶瓷纤维催化剂载体的成型和性能的影响.确定最优的成型工艺,以质量分数0.2％的SDS作浸润助剂,150℃干燥2 min,质量分数30％的硅溶胶作黏结剂,浸渍粘结后烘干,即制...     

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。