高铝水泥系统中硅铝酸二钙向Q相的转变

采用分析纯的化学原料,将高铝水泥中的惰性成分硅铝酸二钙(C2AS,又称钙铝黄长石)转化为水化活性良好的Q相,组成Q相-铝酸-(CA)-七铝酸十二钙(C12A7)水泥系统．并研究转变前后两系统的抗压强度。结果表明：高铝水泥系统中的C2AS,在加入MgO和系统补钙的条件下,经过高温煅烧能够转化为Q相,高铝水泥系统CA-二铝酸-钙(CA2)-C2AS变化为Q相CA-C12A7。Q相-CA-C12A7的烧成温度为1260～1300℃．保温时间为30～60min。组成为Q相-CA-C12A7水泥的抗压强度比组成为CA-CA2-C2AS的高,而且其后期强度持续发展。     

Q相贝利特水泥的烧成条件及抗压强度

研究了6CaO·4Al2O3·MgO·SiO2(C6A4MS,Q相)与贝利特(2CaO·Sio2,C2S)的烧成条件,制备了Q相-C2S-七铝酸十二钙(12CaO·7Al2O3,C12A7) 水泥,探讨了水泥形成条件并检测了抗压强度。研究表明:Q相与C2S能够共存,并组成Q相-C2S-C12A7水泥系统。在Q相-C2S-C12A7水泥系统中, Q相在1270℃开始生成,随着温度的升高,Q相的生成量逐渐增大,1320℃时开始融化,微量的BaO对β-C2S具有较好的稳定作用;Q相-C2S-C12A7 系统水泥的早期强度高,中后期强度有一定的提高。     

微量组分对高铝水泥系统中Q相形成的影响

研究微量组分Fe2O3和P2O5等对Q相-铝酸-钙（CA）-七铝酸十二钙（C12A7）高铝水泥系统中Q相形成的影响。结果表明;Q相-CA-C12A7高铝水泥系统中,掺加微量的Fe2O3抑制Q相的生成,并降低系统的熔点,降低系统的烧成温度。掺加微量的P2O5时,能够促进Q相的形成,P2O5的量过多,会抑制Q相的生成。掺加微量Fe2O3后,Q相-CA-C12A7各龄期的抗压强度略有减少。掺加微量的P2O5后,该水泥各龄期的抗压强度略有增加。     

Q相-CA-C12A7体系水泥材料的初步研究

在前人研究Q相合成基础上,采用正交实验的方法,研究了Q相-CA-C12A7体系水泥的烧成条件及水化性能.研究结果表明:在Q相-CA-C12A7系统中,Q相的形成温度在1260～1340℃之间;Q相-CA-C12A7系统水泥烧成的最佳条件是温度为1320℃,保温时间为40min.此水泥具有早期强度高,中期强度提高快,后期强度不发生倒缩.     

Q相-C2S-C4AF-C12A7系列水泥形成的研究

通过研究Q相与C2S和Q相与C4AF的共存条件,构造Q相-C2S-C4AF水泥系统,对此系统水泥形成条件进行研究.研究表明:Q相与C2S和Q相与C4AF能够共存,可以组成Q相-C2S-C4AF-C12A7水泥系统.在Q相-C2S-C4AF-C12A7水泥系统中,Q相在1270℃开始生成,随着温度的升高,Q相的生成量逐渐增大;采用V2O5对β-C2S具有较好的稳定作用.随着C4AF量的增加,Q相的量也在增加,同时,烧成温度降低.     

石膏对贝利特-硫铝酸钡钙水泥强度和硬化浆体结构的影响

研究了石膏对贝利特-硫铝酸钡钙水泥强度和硬化浆体结构的影响.结果表明:贝利特-硫铝酸钡钙水泥熟料的矿物组成主要有C3S、C2S、C,A、C4AF和C2.7B1.25A3S;当水泥中石膏掺量为10%时,贝利特-硫铝酸钡钙水泥的3d、7 d、28 d和90 d抗压强度分别达到了45.0、61.9、82.1和85.6 MPa;贝利特.硫铝酸钡钙水泥的水化产物主要有AFt、Ca(OH)2、C-S-H凝胶等,随石膏掺量的增加,AFt的数量逐渐增加,水化后期的Ca(OH)2数量逐渐减少.用XRD和SEM来分析硬化水泥浆体组成和结构.     

硫铝酸盐水泥的理化分析研究

采用现代的测试分析手段(XRD,DTA,DTH-TG,SEM,TGA等)对烧制硫铝酸盐水泥的理化过程进行系统的分析研究,得出一些有意义的结论.(1)硫铝酸水泥熟料矿物中,C4A3S的最佳生成温度为1250 ℃,其分解温度≥1 374℃;(2)该熟料矿相中没有生成C4AF等铁铝酸盐矿相的可能性;(3)硫铝酸水泥快凝的原因是熟料中存有CA,C12A7,f-CaO,CaS所致.     

含镁铝尖晶石的铝酸盐水泥制备及力学性能研究

设计不同的水泥熟料物相组成,以石灰石、重烧氧化镁和铝矾土熟料为原料,于1400℃3h处理后制备了含不同量镁铝尖晶石相的铝酸盐水泥。利用XRD和SEM对不同配比的合成产物的物相及形貌特征进行了分析,并对这种新型铝酸盐水泥浇注料进行了抗压强度的测试。结果表明:含镁铝尖晶石的铝酸盐水泥的主要物相为一铝酸钙(CA)、镁铝尖晶石(MA)和二铝酸钙(CA2),还有少量的硅铝酸二钙(C2AS)和残余刚玉(α-Al2O3);浇注料的强度随MA含量的减小而增大,且随水化时间延长,其强度增进稳定。     

硫铝酸锶钙矿物的研究

以硫铝酸盐水泥的主要矿物的硫铝酸钙(C4A3)为基础,用Sr2+对C4A3中的Ca2+进行取代,合成了新的水泥矿物——硫铝酸锶钙系列,研究了该系列矿物试样煅烧后的强度发展规律。结果表明:硫铝酸锶钙系列矿物试样经1300℃煅烧后的抗压强度明显高于硫铝酸钙,抗压强度最大的矿物组成为Ca1.50Sr2.50A3,其3d和28d抗压强度分别为76.6MPa和89.6MPa,用X射线衍射仪、扫描电子显微镜和差热分析仪等对熟料的形成和水化机理进行了初步分析,发现硫铝酸锶钙矿物水化产物主要是钙钒石(AFt),水化铝酸一钙(CAH10),Ca(OH)2以及Al2O3(aq)。     

高硅酸三钙硅酸盐水泥熟料组成及性能的研究

设计了一种石灰饱和系数、硅酸率和铝率分别为0．98,2．4和2．4的新型硅酸盐水泥熟料组成。研究了掺加了质量分数为1％CuO的生料分别在1200,1350,1400,1450℃下保温30min烧结样的矿物相、矿物形貌及性能。X射线衍射及其定量分析结果表明：1450℃烧结样的硅酸三钙(C3S)质量分数为73．37％,晶体尺寸大,主要矿物相为C3S、少量硅酸二钙(C2S)、铝酸三钙(C3A)及铁相固溶体。这种新型高C3S熟料完全可以在传统水泥烧成制度下烧成。该烧结样加入质量分数分别为50％的粉煤灰及5％的石膏制得水泥,其性能符合强度等级为32．5的粉煤灰水泥标准要求。     

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.     

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。     

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.