超细粒子催化剂的研究进展及其应用

介绍了超细粒子催化剂的性质及现有的一些制备方法，并对制备方法的优缺点进行了评价。着重探讨了溶胶-凝胶技术所具备的特点及一些内在缺点，并展望了超细粒子催化剂的应用前景。     

磁性纳米镁铝水滑石的合成研究

利用共沉淀法合成出磁性纳米镁铝水滑石，并借助于XRD，TEM，振动样品磁强计等手段研究了铁（Ⅱ）／镁摩尔比对水滑石结构和磁学性能的影响。这为层状材料与磁性基质进行复合制备新型功能材料提供了实验依据。     

由氢氧化氧铁制备纳米级铁酸锌及产物性质研究木

提出了一种合成铁酸锌纳米粉体的新方法。以二价铁盐为原料，用过氧化氢快速氧化得到氢氧化氧铁（δ-FeOOH）；添加计算量的锌离子经沸腾回流制备出纳米级铁酸锌粉体。利用透射电镜（TEM）、X射线衍射（XRD）、振动样品磁强计（VSM）等手段对产物的形貌、谱学性质、磁学性质等进行了研究。结果表明：该方法制备的铁酸锌微粒的粒径在5～20nm，颗粒形貌为球形且具有超顺磁性。     

多孔Al2O3负载纳米Fe颗粒复合材料的微观结构与磁性能

采用浸渍-还原法制备多孔Al2O3负载纳米Fe颗粒复合材料.利用X射线衍射仪(XRD)、穆斯堡尔谱仪(M(o)ssbauer)和振动样品磁强计(VSM)对样品的微观结构及磁性能进行了研究.发现铁元素以纳米级单质Fe颗粒和超顺磁态α-Fe2O3(< 20 nm)的形式存在.通过穆谱知,氢气气氛600 ℃还原3 h, 59.9%铁元素转变为单质铁.浸渍-还原方法能在较低温度下成功制备不同组成、微观结构及磁性能的多孔磁性材料.     

钕改性铁基催化剂用于氮氧化物脱除

采用分步浸渍法，分两步将金属铁和钕依次引入商业化成品二氧化钛表面，研究其脱硝性能。通过X射线衍射(XRD)、氮气吸附-脱附(N₂-BET)、X射线光电子能谱(XPS)、氨程序升温脱附(NH₃-TPD)、氢气程序升温还原(H₂-TPR)等方法对样品进行表征分析。通过氮气吸附-脱附发现，钕的引入使得负载铁后的催化剂比表面积减小。X射线衍射分析结果表明，引入的金属物种在催化剂表面具有良好的分散性。氨程序升温脱附测试结果显示，钕的引入增加了催化剂的总酸量，同时改变了催化剂的酸性分布。X射线光电子能谱测试结果表明，钕改性增加了催化剂表面吸附氧和铁(Ⅱ)的含量，有利于脱硝反应的进行。氢气程序升温还原测试结果表明，钕的引入使得催化剂氧化还原性能略有下降。活性测试结果表明，适量钕负载有利于提升催化剂的脱硝性能，钕元素在催化剂中的质量分数为9%时催化剂表现最优，最佳脱硝效率为81.4%。     

由氢氧化氧铁制备纳米级铁酸锌及产物性质研究

提出了一种合成铁酸锌纳米粉体的新方法.以二价铁盐为原料,用过氧化氢快速氧化得到氢氧化氧铁(δ-FeOOH);添加计算量的锌离子经沸腾回流制备出纳米级铁酸锌粉体.利用透射电镜(TEM)、X射线衍射(XRD)、振动样品磁强计(VSM)等手段对产物的形貌、谱学性质、磁学性质等进行了研究.结果表明:该方法制备的铁酸锌微粒的粒径在5～20 nm,颗粒形貌为球形且具有超顺磁性.     

纺锤形α—Fe磁粉制备过程热处理工艺的研究

本文利用ＦｅＳＯ４与Ｎａ２ＣＯ３合成了纺锤形α－ＦｅＯＯＨ微粒，在流态化床中进行脱水、还原等热处理工艺，探讨了热处理工艺对产物磁性能的影响，发现随脱水温度的升高，产物的磁性能有显著的提高，而还原温度的提高最终产物的磁学性能会下降。     

铁琼脂糖磁性微球的制备和表征

采用反相悬浮包埋法制备了以纳米铁粉为磁核、琼脂糖为壳层的铁琼脂糖磁性微球,其磁响应性比以四氧化三铁为磁核的琼脂糖磁性微球好得多;并对不同粒径的琼脂糖磁性微球表面的活性基团进行了测定,粒径为8.3 μm的铁琼脂糖磁性微球的表面活性羟基数目是4.02×1015个·mg-1.     

微量K掺杂对样品La0.75Sr0.25-xKxMnO3的磁性、电输运及室温磁电阻的影响

采用溶胶-凝胶方法制备了系列样品La0.75Sr0.25-xKxMnO3(x=0.00,0.05,0.07,0.10).对系列样品进行了相结构、磁性和电输运性质的研究.XRD数据表明:系列样品具有完整的钙钛矿锰氧化物结构.通过对磁性和电阻率的研究发现:与双交换作用相比,A位离子的无序度2对样品的磁性和电输运的影响起主要作用.随掺杂量的增加,磁电阻的峰值逐渐增大;峰值温度逐渐下降,更接近室温.在210～280 K的温区内,磁电阻基本保持稳定.这些结果都有利于磁电阻的实际应用.     

磁稳定床及磁性催化剂的研究进展

对磁稳定床及磁性催化剂在石油化工和生物工程等领域的应用进行了归纳总结。磁稳定床已经应用于催化加氢、烟尘净化、干法选煤、生化分离、固定化生物反应器、细胞培养等过程。与传统工艺相比,磁稳定床兼有固定床和流化床的优点,能强化受传质传热限制的反应过程,提高反应效率,在实际应用中显示出独特的优越性。磁性催化剂的设计与开发是磁稳定床应用的关键,目前磁性催化剂以包覆型催化剂为主,其共同特点是具有适宜的磁性和低温反应活性,利于反应操作。磁稳定床及其磁性催化剂的研究开发是催化剂工业发展的一个新方向。     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

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。     

Inorganic/organic nanocomposite coatings: The next step in coating performance

Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.