SiO_2包覆CaCl_2·2H_2O相变纳米复合材料的制备及表征

结晶水合物盐是一类无机相变储能材料,其存在相分离、过冷等现象,无法获得实际应用。通过溶胶-凝胶法制备SiO_2包覆CaCl_2·2H_2O相变纳米复合材料,并通过XRD、EDS、SEM和TEM对样品进行表征。DSC和STA分析结果表明,样品具有良好的储热性能和热稳定性。样品的相变温度为75. 8℃,相变焓为52. 89 J/g。热循环实验表明其具有良好的热循环性能。水合盐的相分离、过冷现象得到了有效抑制和减轻,这是由于介孔限域效应的作用结果。     

水淬渣-粉煤灰基4A沸石的制备及性能表征

粉煤灰因其主要成分为二氧化硅、三氧化二铝常被用来当作合成沸石的原材料,合成的沸石类型主要有X型、Y型、A型、ZSM-5型等,相关合成技术也已非常成熟。水淬渣是高炉炼铁水淬急冷产生的高炉渣,对其主要利用方式是作为水泥、路基材料,均属低附加值利用。通过碱熔水热法利用水淬渣、粉煤灰混合原料合成4A型沸石。初步探究硅铝物质的量比（简称硅铝比）、熔融温度、熔融时间、晶化时间对制备的沸石样品品质造成的影响,得到最佳制备条件：硅铝比为1.0、碱灰质量比为1.5、碱熔时间为1 h、碱熔温度为600 ℃、老化时间为12 h、灰水质量比为1∶5、晶化温度为90 ℃、晶化时间为16 h。对合成的沸石进行X射线衍射（XRD）、X射线荧光光谱（XRF）、扫描电镜（SEM）、红外光谱（FT-IR）等表征,结果表明利用水淬渣、粉煤灰合成的4A型沸石各方面性能良好,具有超高的工业化生产价值。     

高导热膨胀石墨/棕榈酸定形复合相变材料的制备及储热性能研究

采用棕榈酸(palmitic acid, PA)作为相变材料,膨胀石墨(expanded graphite, EG)作为添加基质,通过"熔融共混-凝固定形"工艺制备了PA/EG定形复合相变材料以提高相变材料的综合性能。预测并制备了21种不同配比的定形复合相变材料,对其形貌结构和孔隙率进行了微观表征与理论分析,并在此基础上对样品进行了传热性能分析、热物性测试、热稳定性研究和储热性能分析。SEM形貌分析显示所使用工艺可使棕榈酸能较好地被吸附于膨胀石墨的孔隙结构并使之均匀分布;DSC测试结果表明定形复合相变材料[70%(质量) PA]的焓值为193.01 J/g,纯PA的焓值为275.35 J/g,对应于熔点分别为61.08℃和59.53℃。EG的添加,可有效提高相变材料的热导率。当样品密度为900 kg/m3,EG含量为30%(质量)时,定形复合相变材料的热导率为14.09 W/(m·K),相比于纯PA [0.162 W/(m·K)]提高约87倍;对制备的样品进行50次循环稳定性实验,EG含量为24%(质量)和30%(质量)的样品形态均未出现明显变化,表现出良好的充放热循环稳定性。     

常压水热合成纳米氧化锆工艺研究

以ZrOCl2.8H2O和氨水为主要原料,利用常压水热工艺制备出纳米氧化锆粉体,系统研究了氧氯化锆浓度、pH、反应温度及时间对产物晶型、粒度的影响,得出制备氧化锆纳米粉体的最佳工艺条件。并结合X射线衍射分析、透射电镜等方法对样品进行表征。结果表明,所制得的氧化锆样品为纳米氧化锆粉体,且粒度较均匀、分散性好,平均粒径约为7 nm。     

不同晶型碳酸钙的仿生矿化研究

以吐温-80为表面活性剂,采用气相扩散技术制备出不同晶型的碳酸钙样品.获得的样品试用X-射线衍射(XRD)、和扫描电镜(SEM)等手段进行表征.结果表明,碳酸钙材料的物相组成和形貌与溶液中吐温-80体积含量和体系温度密切相关.在含有吐温-80的情况下,在30～50℃的范围内,获得的产物几乎全为球霰石;当温度达到70℃,部分产物转变为文石.实验结果的获得对制备该类材料提供了有益的实践参考.     

氧化铜灼烧温度对磷酸铜胶粘剂粘接强度的影响

沉淀法制备的氧化钢用不同的温度灼烧，再与多聚磷酸盐、促进剂、添加剂等组份调酸，发现当氧化铜灼烧温度在８５０℃时，压剪强度达８０．８ＭＰａ。用差热－热重分析，温度在１０５０℃范围内没有相变。未经灼烧和６５０℃、９４０℃、１０５０℃灼烧的氧化铜粉末样品，经Ｘ射线衍射实验，证实氧化铜全部为单斜晶型。氧化铜晶粒随着温度的升高长大，改变了低温时细晶粒聚集的疏松收集合体，降低了表面能。排除了氧化铜晶型改变对胶粘剂强度的影响因素。     

高导热膨胀石墨/棕榈酸定形复合相变材料的制备及储热性能研究

采用棕榈酸(palmitic acid, PA)作为相变材料,膨胀石墨(expanded graphite, EG)作为添加基质,通过“熔融共混-凝固定形”工艺制备了PA/EG定形复合相变材料以提高相变材料的综合性能。预测并制备了21种不同配比的定形复合相变材料,对其形貌结构和孔隙率进行了微观表征与理论分析,并在此基础上对样品进行了传热性能分析、热物性测试、热稳定性研究和储热性能分析。SEM形貌分析显示所使用工艺可使棕榈酸能较好地被吸附于膨胀石墨的孔隙结构并使之均匀分布;DSC测试结果表明定形复合相变材料[70%(质量) PA]的焓值为193.01 J/g,纯PA的焓值为275.35 J/g,对应于熔点分别为61.08℃和59.53℃。EG的添加,可有效提高相变材料的热导率。当样品密度为900 kg/m³,EG含量为30%(质量)时,定形复合相变材料的热导率为14.09 W/(m·K),相比于纯PA[0.162 W/(m·K)]提高约87倍;对制备的样品进行50次循环稳定性实验,EG含量为24%(质量)和30%(质量)的样品形态均未出现明显变化,表现出良好的充放热循环稳定性。     

热聚合温度对煤液化沥青制备中间相沥青的影响

为制备优质的中间相沥青,以煤液化沥青为原料,在不同热聚合温度下制备中间相沥青,采用偏光显微镜、红外光谱仪、XRD、热分析等测试仪器对所得中间相沥青进行分析和表征。结果表明,温度对中间相沥青的收率、形貌和结构影响显著。随着温度升高,中间相沥青的收率降至86.2%,H含量降至3.96%,S含量有所下降,残炭率增大;中间相小球体的尺寸增大,逐渐出现融并现象,最终形成广域型中间相;煤液化沥青中的稠环芳烃、芳香烃的含量明显增加,烷烃成分则明显减少;煤液化沥青中的无定型区含量减少,分子的排列与取向性变好。选择低的热缩聚温度(410~420℃),适当延长反应时间有利于反应方向的控制,从而达到制备优质中间相的目的。     

低温可逆热致变色材料[NH_3（CH_2）_2NH_3]CuCl_4

用液相法合成了有机-无机杂合物[NH3（CH2）2NH3]CuCl4,通过元素分析、XRD对产物进行了表征,采用DSC研究了杂合物的变色温度,在-16℃左右有明显变色峰,与目测实验结果一致。其变色机理是无机阴离子层发生固-固相变所致,发现该杂合物是一种反复性良好的低温可逆热变色性材料。     

钼氟共掺杂二氧化钒的制备与表征

本文采用水热法制备钼氟共掺杂VO_2粉体,运用扫描电子显微镜(SEM)、X-射线粉末衍射仪(XRD)、X-射线能谱仪(EDS)和热分析仪(DSC)探究了煅烧温度、水热时间、掺杂量、对粉体制备的影响;填充比、尿素含量、反应液浓度对粉体形貌的影响;以及掺杂比例对VO_2相变温度的影响。结果表明:不同煅烧温度可以制备出不同的钒氧化物,其中600℃附近的煅烧温度比较适合制备M型VO_2,水热时间的增长有利于M型VO_2的生成;通过改变填充比、尿素含量和反应物浓度,可以制备出不同的形貌的M型VO_2;通过掺杂钼氟元素可以降低VO_2的相变温度,其中1.5%的钼氟掺杂比的相变温度可以达到48.6℃。     

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。